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6gb1yx
|
why when you miss somebody can you physically feel it in your chest?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6gb1yx/eli5_why_when_you_miss_somebody_can_you/
|
{
"a_id": [
"diow2cm"
],
"score": [
2
],
"text": [
"It's called *heartache.*\n\n_URL_2_\n\n_URL_0_\n\n_URL_4_\n\n_URL_5_\n\n_URL_3_\n\n_URL_1_"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/explainlikeimfive/comments/64b0ev/eli5_why_do_we_get_heartaches_when_feeling_sad/dg0zyg7/",
"https://www.reddit.com/r/explainlikeimfive/comments/1wgxk5/why_does_my_heart_actually_feel_heartbroken_or/",
"https://www.reddit.com/r/explainlikeimfive/comments/3noj6u/eli5_what_is_the_feeling_in_your_chest_when_hurt/",
"https://www.reddit.com/r/explainlikeimfive/comments/1ehu9q/eli5_why_does_heartache_physically_hurt_my_chest/",
"https://www.reddit.com/r/explainlikeimfive/comments/24u26f/eli5_why_does_my_heart_feel_heavy_when_im_sad_or/",
"https://www.reddit.com/r/explainlikeimfive/comments/33n4if/eli5_why_do_we_get_a_heartache_when_sadpanicked/"
]
] |
||
cslkaz
|
why plants don’t suffer negative effects from inbreeding
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/cslkaz/eli5_why_plants_dont_suffer_negative_effects_from/
|
{
"a_id": [
"exfi8ix",
"exfib05"
],
"score": [
7,
3
],
"text": [
"There are issues with inbreeding plants. A major issue is that they will all be susceptible to the same diseases. Bananas are all clones, and if there's a particular disease that develops, it could wipe out all of the bananas in the world. In fact the world used to commonly eat the Gros Michel banana, but it got decimated by a fungus in the 1950s and now we eat Cavendish bananas instead.",
"It does, but the effects aren't always so visibly obvious because it's pretty hard to break a plant.\n\nThe broader concerns of narrow gene pools are still present, down to the extreme example of the all-clone banana crop's severe infection weakness."
]
}
|
[] |
[] |
[
[],
[]
] |
||
7z423o
|
Did the early 15th century in the Kingdom of Bohemia feature multiple races, religions, etc.?
|
[deleted]
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7z423o/did_the_early_15th_century_in_the_kingdom_of/
|
{
"a_id": [
"dul7e5k"
],
"score": [
3
],
"text": [
"This question has been answered time and time again in the last few weeks: \n_URL_4_ \n_URL_0_ \n_URL_3_ \n_URL_2_ \n_URL_5_ \n_URL_1_"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/7v1lil/people_are_getting_extremely_upset_because_there/",
"https://www.reddit.com/r/AskHistorians/comments/7rkol0/the_video_game_kingdom_come_deliverance_recently/",
"https://www.reddit.com/r/AskHistorians/comments/4ipxz3/is_it_plausible_for_moors_or_other_blackskinned/",
"https://www.reddit.com/r/AskHistorians/comments/7y8rxt/how_diverse_was_bohemia_during_the_fifteenth/",
"https://www.reddit.com/r/AskHistorians/comments/7y3zas/in_kingdom_come_deliverance_set_in_1400s_bohemia/",
"https://www.reddit.com/r/AskHistorians/comments/7yyl1m/newly_released_video_games_attempt_to_accurately/"
]
] |
|
4f5eci
|
are the 7+ magnitude earthquakes in japan and ecuador related?
|
Seems strange to have multiple 7+ magnitude earthquakes hit a city in each hemisphere within a week. Are these events related? Are the earthquakes in Ecuador a result of the earthquakes in Japan?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4f5eci/eli5_are_the_7_magnitude_earthquakes_in_japan_and/
|
{
"a_id": [
"d2626ii"
],
"score": [
2
],
"text": [
"Earthquakes happen pretty frequently, far more frequently than most people realize. Most of them are very small and don't catch much attention, though anyone of them could turn out to be damaging. That's the thing about Earthquakes they can be pretty unpredictable, and two being about the same strength and news worthy happening around the same time is more of a luck of the draw thing. "
]
}
|
[] |
[] |
[
[]
] |
|
3cs4wk
|
why after shaving do i get pimples?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3cs4wk/eli5_why_after_shaving_do_i_get_pimples/
|
{
"a_id": [
"csyf8pq",
"csyl4we",
"csyllob"
],
"score": [
14,
3,
3
],
"text": [
"Small nicks or cuts on your skin get infected. Hairs once cut smooth to the skin have a chance of becoming ingrown and infected. And you can sometimes push dirt and bacteria into a pore causing it to become infected. ",
"Always. Always disinfect your blade. So much bacteria live on razor blades. Then people use them to expose areas of their bodies (face, neck, legs) to the bacteria while cutting the hair. You introduce bacteria, you get pimples. Clean your razor very, very well. I tend to use extremely hot water, and some rubbing alcohol before razor shaving, and I get far fewer pimples and less razor burn.",
"Razor bumps are ingrown hairs. Either you shaved too close, and the hair is growing beneath the skin (which looks like a big pimple and hurts like crap); or you pushed the hair over into a neighboring follicle (mild red bumps that don't hurt or puss as much).\n\nOccasionally, I would get the former (growing beneath the surface) along my chin line. Mainly, this came from shaving up (against the grain) with shaving cream. It was a nice smooth shave, but I would pay for it the next day. Now I just \"take off the top\". I shave down with hot water. I haven't had a bad ingrown hair yet. But I do still get the mild bumps, probably because I don't replace my razor often enough."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
1qwe5h
|
how are commercials cost-effective to a company? has anyone ever seen a comercial and thought, "wow! i'm going to go buy that."
|
I'm thinking about Superbowl ads...millions of dollars for 30 seconds of glory. Do companies just have an absurd amount of money to spend?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1qwe5h/eli5_how_are_commercials_costeffective_to_a/
|
{
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"cdh5wle",
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"cdhdgd4",
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],
"score": [
27,
20,
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"text": [
"It's not about pushing units.\n\nWell it is... but not always. Commercials and marketing have a lot to do with brand recognition and outreach.\n\nSo when Bud Light is paying millions to show you a super bowl ad, they aren't expecting you to leap up and buy more bud light. They are trying to give you a positive view of their brand (hence why those ads are usually funny/heartwarming) so that the next time you are in the market buying beer Bud Light will stick out to you.",
"ROMI or return on Marketing Investments are generally very difficult to objectively quantify. Many companies justify the costs of large marketing campaigns not because of the immediate return (i.e. I want that! I will go out and buy it now) but rather the purchases made by brand or product awareness. In these cases, most customers are casually shopping and will purchase the advertised brand simply because they have seen it before 'somewhere' and trust the legitimacy of the product or service. \n\nBrand awareness is also has longer term value as customers who become familiar with a particular product will stick with the brand out of convenience rather than researching potential unfamiliar alternatives even if competing products may be superior.",
"Most of the time it isn't \"Yeah, I'm gonna go buy that\"\n\nIt's \"I want stuff, I'll buy that stuff\"\n\nThink of Coke vs Pepsi, you are a Pepsi person all the way, and then you see a superbowl ad, or some other ad for coke and when you are buying pop, you go \"Maybe I'll get coke this time\"",
"I understand the intent behind the marketing (brand association, etc), but I was hoping for more of a quantifiable assessment which /u/Rootle pointed out is difficult. Even in a non-superbowl marketing environment, it just seems as if companies spend absurd amounts on commercials and I was truly curious as to the ROI they got. One can assume Amazon, Apple, Microsoft, Ford, etc has a tremendous ROI due to marketing and was curious if there was data to back it up (other than company's profits & worth).\n\nMaybe I'm just hard to persuade, but I've never bought a product because of a commercial. At least not knowingly. ;-)",
"Spending millions (billions) of dollars on ads is the difference between Coke-a-cola and RC cola. \n\nNobody wants a freaking RC cola. Even though objectively, they are the same thing really.",
"Marketing/Advertising is all about making sure that when its time to make a purchase, your product/service/company is part of the equation. \n\nTwo forces in any market are competition within the market, and the threat of substitutes. Through marketing and advertising, companies can try to lessen the impact those forces have on their marketshare and bottom line. \n\nTake Coca-Cola for example. Their flagship product, Coke, is one of thousands if not millions of the non-alcoholic beverages available to consumers. When you're thirsty, Coke isn't just competing against Pepsi - they're competing against every beverage available to you at your point of purchase. \n\nIn order to make sure that when you are getting a beverage Coke or one of their other products is what comes to your mind first or is at least near the top of your list CocaCola spends in the neighborhood of $3 Billion (yes, with a b) per year on advertising. They don't expect you to see their commercial or magazine ad, or corporate sponsorship badge and go buy their product; they want you to associate their product with good things and various situations and therefore make you more likely to purchase Coke instead of Pepsi, or Mountain Dew, or FIJI Water, or Snapple.. etc. ",
"Consumer exists on a spectrum of interest from completely disinterested to heavily researching and committed to buy. \n\nCompanies create commercials to affect the consumer on every area on the spectrum, because if someone slides down the continuum from \"disinterested\" to \"interested,\" their initial evaluations of their purchasing options are impacted by \"brand awareness.\"\n\nYou're not going to be able to hard-sell someone who's watching TV into going out and buying a bottle of Coca Cola or a bag of Doritos, and advertising reflects this. They don't exhort the particular qualities of their food (or makeup, or chewing gum or gasoline or whatever) over others so much as they try to create a memorable experience associated with that brand name, and in general associate it with good feelings (pretty people parting with cans of Dr. Pepper or a funny mascot selling Cheetos). That way, when you are at the grocery store and deciding between whether to buy Speed Stick or Old Spice, you have a stronger memory of the Isiah Mustafa commercials, and are more likely to buy if you are not already committed to one product over the other. \n\n"
]
}
|
[] |
[] |
[
[],
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[],
[],
[],
[],
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] |
|
7ntefk
|
Why do cities in the US advertise their population size on their signs? What purpose does or did it serve?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7ntefk/why_do_cities_in_the_us_advertise_their/
|
{
"a_id": [
"ds5nfso"
],
"score": [
13
],
"text": [
"Old thread, but not too much in there. u/MrDowntown gave an answer but it's unsourced. \n\n_URL_0_\n"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/3dk7tr/why_are_population_numbers_generally_listed_on/"
]
] |
||
hvnbo
|
If I was in space could I lift a 5000 lb. weight?
|
Let's say I was strapped to the outside of a space shuttle holding me in place but not orbiting earth, say I was just in dead space. Would I be able to push/pull a 5000 lb weight?
|
askscience
|
http://www.reddit.com/r/askscience/comments/hvnbo/if_i_was_in_space_could_i_lift_a_5000_lb_weight/
|
{
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"c1yr829"
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5,
2,
4,
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],
"text": [
" > Would I be able to push/pull a 5000 lb weight?\n\nYes. The 5000 lb mass would not have any appreciable weight (since weight is a function of gravity).\n\nIt would, however, have considerable inertia. This means it would take a long time for you to push/pull it.",
"considering that once in space, there are no concept of up and down anymore, \"lifting\" also loose its meaning. \n\nas a kid i use to pretend to \"lift\" the whole planet, by standing on my arms.",
" > a space shuttle holding me in place but not orbiting earth, say I was just in dead space.\n\nOrbiting is the same as being in free-fall which is the same as floating motionless in the middle of empty space, which is to say they are all inertial reference frames.\n",
"Barely. As you push it, it pushes back. You are both given the same amount of momentum, but because you weigh so much less, you go flying in one direction while the weight will slowly float the opposite way.",
"If you were in a theoretical no gravity environment, there's no such thing as weight. But I know what you mean, then I must ask you, if you are in 0 gravity, what's the difference between lifting something and going underneath something? Even if you were attached to a space vehicle that's much larger than 5000lb mass, you would still not be \"held in place\". The center of mass in the vehicle, person, 5klb mass block system would remain conserved. If you move that mass up, you (and the ship) will move down. It's actually the same if you were on earth, when you jump, the earth moves down, just that the mass discrepancy is so large that you don't notice."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
|
1fu30o
|
Best sources for book reviews, circa 1950s?
|
I'm looking for book reviews for a book published in 1953 (Seduction of the Innocent, by Frederic Wertham), and need a good place to start, besides a simple google search.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1fu30o/best_sources_for_book_reviews_circa_1950s/
|
{
"a_id": [
"cadwb1p"
],
"score": [
2
],
"text": [
"For academic social science or humanities book reviews, I would suggest [Jstor](_URL_1_). If you don't have access yourself, find someone who attends or teaches at a university, and who is willing to make a few searches for you.\n\nFor non-academic reviews, I would suggest looking through the archives of various book review publications of the period, such as the New York Times Book Review or Publisher's Weekly. Gale has a [Book Review Index](_URL_0_), but again, you probably need to find someone with university affiliation to get access."
]
}
|
[] |
[] |
[
[
"http://www.gale.cengage.com/BRIOnline/quick.htm",
"http://www.jstor.org/"
]
] |
|
113urm
|
Will the rising sea-levels pose a risk to the major countries of the world?
|
Hearing about that one island nation's (the name escapes me) plan for mass evacuation due to the rising oceans made me think about this. Will places like the United Kingdom, Madagascar, the nations in the Carribean, etc. face any major issues from the rising water?
|
askscience
|
http://www.reddit.com/r/askscience/comments/113urm/will_the_rising_sealevels_pose_a_risk_to_the/
|
{
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],
"score": [
15,
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2
],
"text": [
"Yes many places will experience severe problems due to the rise in sea level. A good place to start are the IPCC reports.\n\n[A chapter on coastal systems and low-lying areas](_URL_0_)\n\n[A chapter on small islands](_URL_14_)\n\n[A chapter on current observations, and what we might expect given different modeling scenarios.](_URL_12_). Essentially the IPCC has 4 different models. They put raw data into the models but change 'human responce' factors. Basically they go from: \"we don't do anything to mitigate climate change and we emit GHG's at higher rates\", to \"we do everything we can to mitigate climate change and reduce our GHG output\". That is why you have varying levels of sea level change being reported. If we do everything we can, then we expect that sea level change won't be as dramatic compared to if we do nothing.\n\n[Here is an older study](_URL_5_) which assesses the risks of the low-lying island nations you were thinking about. They are in the south-pacific. \n\nOther nations or areas which will be severely impacted:\n\n[Bangladesh](_URL_9_): \"Bangladesh is now widely recognised to be one of the countries most vulnerable to climate change. Natural hazards that come from increased rainfall, rising sea levels, and tropical cyclones are expected to increase as climate changes, each seriously affecting agriculture, water and food security, human health and shelter.[39] It is believed that in the coming decades the rising sea level alone will create more than **20 million**[40] climate refugees.\" Even if this number is off by 50% we are talking about relocating 10 million people.\n\nImpacts for [Canada](_URL_13_) from the canadian government. \n\nThe [USA](_URL_15_): on sea level rise by region. \n\n[Louisiana](_URL_2_):\"The southern coast of Louisiana in the United States is among the fastest disappearing areas in the world. This is largely a consequence of human mismanagement of the coast...Rising sea waters have exacerbated the problem. Some estimates conclude that the state is losing a land mass equivalent to 30 football fields every day.\"\n\n[The Netherlands](_URL_10_): Much of the country lies below sea level, and they are already retrofitting and preparing for sea level rise. This is a great example of a country that has the ability to adapt because they have the resources to do so. Other countries may not have the resources, either monetary or in time to effectively adapt. \n\n[Costal cities](_URL_11_) that are at or near sea-level. A very short list includes - New Orleans, New York, London, Shanghai, Vancouver, Venice, and Bangkok. Islands like the [maldives](_URL_8_), more on [maldives](_URL_3_) \n\nWikipedia has a good article on [sea level rise](_URL_4_). \n\n[Greenpeace on sea level rise](_URL_6_)\n\n[National Geographic on sea level rise](_URL_7_)\n\n[Skeptical science on sea level rise](_URL_1_)\n\nTL;DR: any coastal area where there are parts of the country or city are near or below sea level will be impacted by sea level rise. The ability of the country to adapt to the change will make a big difference in how people are effected. \n\n",
"The country you were thinking of was Kiribati. Another factor of climate change that people don't think about as often in terms of the ocean is temperature rise. Consider how many countries either make their livings by fishing or it is a major part of their economies. Many small island nations get their protein almost exclusively from the oceans. Coral reefs are some of the most fragile ecosystems on the planet. Corals have a very small temperature range that they can survive in. When temperatures rise, corals bleach and die and this is already happening at an alarming rate. When the corals die, the entire ecosystem will collapse and all the fish will die. Dozens and dozens of island nations will suddenly be without food and more will lose a substantial part of their economy. \n\nEdit* I can't math.",
"Quick answer:\n\nSea levels rise because of melting land ice. Melting sea ice does not cause a rise in sea levels because it's already in the water. Anyway, there are two major land ice sheets in the world, the one in Antarctica and the one in Greenland. The Greenland ice sheet is the only one that's really in danger of melting, and contains about a tenth of the ice as the Antarctica one does. If the Greenland ice sheet melts, that would cause a 20-foot (6 meter) rise in sea levels. The Antarctica ice sheet melting would cause a 200-foot (60 meter) rise in sea levels. But again, there's very little chance of the Antarctica ice sheet melting, because temperatures are so far below freezing there.\n\nEdit: Sea levels have been rising at a rate of about an inch (2.5 cm) every ten years. So even though it's a problem, it's not like it'd all happen overnight."
]
}
|
[] |
[] |
[
[
"http://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch6.html",
"http://www.skepticalscience.com/sea-level-rise.htm",
"http://en.wikipedia.org/wiki/Louisiana#Climate",
"http://www.bbc.co.uk/learningzone/clips/rising-sea-levels-in-the-maldives/3192.html",
"http://en.wikipedia.org/wiki/Current_sea_level_rise",
"http://www.int-res.com/articles/cr/12/c012p137.pdf",
"http://www.greenpeace.org/international/en/campaigns/climate-change/impacts/sea_level_rise/",
"http://ocean.nationalgeographic.com/ocean/critical-issues-sea-level-rise/",
"http://en.wikipedia.org/wiki/Geography_of_the_Maldives",
"http://en.wikipedia.org/wiki/Bangladesh#Climate",
"http://en.wikipedia.org/wiki/Netherlands#Floods",
"http://www.huffingtonpost.com/2012/08/25/drowning-nations-sea-level-rise_n_1783931.html",
"http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch5.html",
"http://www.ec.gc.ca/Publications/default.asp?lang=En&xml=297D1933-034A-4BD2-996E-C83FAA1C8016",
"http://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch16.html",
"http://www.epa.gov/climatechange/impacts-adaptation/"
],
[],
[]
] |
|
bz0jav
|
how do things like marijuana and alcohol get consumed through the mouth/stomach/lungs and then have an affect on the brain?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bz0jav/eli5_how_do_things_like_marijuana_and_alcohol_get/
|
{
"a_id": [
"eqodmaa"
],
"score": [
3
],
"text": [
"When you inhale, most of the stuff you're inhaling goes right into your blood. That's what the lungs are for, getting oxygen from the outside into your blood.\n\n & #x200B;\n\nSame with the digestive system. Your blood is what delivers nutrients to your body, so it has to get into your blood.\n\n & #x200B;\n\nNot everything in your blood can get into your brain. There is a blood-brain barrier to protect your brain from blood irregularities, but some things make it through."
]
}
|
[] |
[] |
[
[]
] |
|
1kn576
|
engine torque
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1kn576/eli5_engine_torque/
|
{
"a_id": [
"cbqmrc5",
"cbqqkqs"
],
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4,
2
],
"text": [
"Torque is a measure of how much force you apply to cause something to twist/rotate. So when you use a screwdiver, or open a bottle of soda, you're applying torque to the screw or bottlecap respectively.\n\nAn engine's torque tells you how much torque the engine applies to your wheels -- which is a really handy measure because, as useful as horsepower is, ultimately if your wheels aren't spinning fast enough to use all that horsepower, you're not gonna be pleased going around just telling people how many HP it has.",
"Torque is the ability of the engine to do work. A car with 150 lbs/ft will feel half as strong as a car with 300 lbs/ft because it can only do half the work. This is why big V8s can have the same horsepower rating as another car but just feel faster all around. Horsepower is also the rate at which torque is applied so torque also determines a vehicles maximum horsepower as well.\n\nEdit:Math"
]
}
|
[] |
[] |
[
[],
[]
] |
||
830ic2
|
when we close our eyes do we actually see the color black or do we see something different that our brain is telling us is the color black but it's not? what's our brain telling our eyes to see when we close them?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/830ic2/eli5_when_we_close_our_eyes_do_we_actually_see/
|
{
"a_id": [
"dve5wua",
"dve6klr"
],
"score": [
2,
2
],
"text": [
"Any \"color\" you see is ultimately your brain's interpretation of the signals is receiving from the eyes, which itself is formulated based on the cells that are stimulated by the light striking them. When you close your eyes, there is a (relative) absence of light, and so an absence of stimulation, and so no image for your brain to form. ",
"Mistake me if im wrong but arent we just looking at the flap of skin we call eyelids? Because they are so thin we can sometimes see illumination coming externally. \n\nAnd just like the other user said, any colour we do see are signals from the brain, dreams, day dreams, and so on.\n\n And any signal being sent from the optic nerves would only be of said shut eyelid until our eyeballs begin to shutter in rem."
]
}
|
[] |
[] |
[
[],
[]
] |
||
33axco
|
why does it seem like nascar is for red necks but formula1 is a high class sport?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/33axco/eli5_why_does_it_seem_like_nascar_is_for_red/
|
{
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"text": [
"Because F1 is European. They don't have rednecks in Europe. That makes all the difference.",
"It's how the two evolved that is the key here. NASCAR grew out of stock car/drag racing which was open to anybody who could afford a car and knew how to soup them up AKA mechanics and good-ol-boys. It was a US creation.\n\nF1 has always been a rich man's sport. It is the Nth of what one can do with unlimited cash in the racing world. The same class of people who owned F1 racers own racing horses, yachts, etc. It was an elite EU creation.",
"Because you're preconditioned to believe that only southerners watch NASCAR and that all southerners are rednecks. \nI found the most recent study I could find and it states that [1 in 3 adults watch NASCAR or 75 million people and broadcasts in 150 countries.](_URL_0_) ",
"F1 grew out of the tradition of top auto manufacturers racing their cars against each other to prove that their automobiles were the best. It was about building the fastest, most reliable, and most technically powerful car.\n\nNASCAR grew out of a history of selling illegal moonshine liquor. To evade the police, bootleggers would strip their cars down as much as possible to make them light and fast. They thought it was fun, so they started racing against one another on the side. \n\nBasically, F1 has always been about million dollar companies facing other million dollar companies. NASCAR didn't become like that until much later."
]
}
|
[] |
[] |
[
[],
[],
[
"http://www.forbes.com/sites/steveodland/2012/02/27/nascars-back/"
],
[]
] |
||
bis3cg
|
on products like sodas or snacks it states something along the lines of “not for resale” or “not to be sold individually”. how do things like concession stands get away with this?
|
I could be misunderstanding the intentions of what this means but my current understanding is that you can’t buy this box of candy and resale them individually. If someone could educate me on this & what the label actually means that would be great
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bis3cg/eli5_on_products_like_sodas_or_snacks_it_states/
|
{
"a_id": [
"em2m0eh",
"em2m1es",
"em2m7kw"
],
"score": [
3,
13,
6
],
"text": [
"Don't quote me on this, but this label is put on products by manufacturers who want to sell items in bulk (chips, sodas, etc.) It prevents retailers from opening up the bulk packaging and selling items individually, often at a higher price per-item. I don't think it was intended or applies for fundraisers or Junior-Varsity basketball game snack bars.",
"The manufacturer sells them in bulk to be used for things like concession stands, but they aren't barcoded and they don't have the appropriate nutritional information on them to be sold individually as there are packaging laws that have to be followed.\n\nConcession stands are exempt from these sorts of rules, as they aren't really a \"retail\" outlet. So it's legal for them but would be illegal for a 7-Eleven to do the same thing.",
"Depends on where you are at, but the issue here is the labeling. With bundled items like this, the nutritional and other information is on the container, not each individual item. However, this does not always translate into an actual legal restriction on individual resell. It's more of a notice to the potential buyer that there may be information about the product they aren't aware of because it is printed elsewhere."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
3gdxqr
|
Why exactly does the conflict in South Ossetia occure?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/3gdxqr/why_exactly_does_the_conflict_in_south_ossetia/
|
{
"a_id": [
"ctxc6yl"
],
"score": [
2
],
"text": [
"We have a 20 years rule, so ask historians can only help you with the least controversial parts of it. \n\nZviad Gamsakhurdia (a jailbird dissident nationalist akin to the American black panthers) won the first multi-party elections in Georgia in October 1990 (a year before USSR was dissolved) and in December same year his government abolished the Autonomous Republics of the Osetians, Abkhazians and Muslims in Georgia which prompted the (elected, too) authorities in Adjara, South Osetia and Abkhazia to declare indepedence.\n\nSource: Georgia's Conflicts by Niklas Nilsson."
]
}
|
[] |
[] |
[
[]
] |
||
4ftmrf
|
Can someone tell me about the government of Weimar Germany?
|
My professor said that the individual cabinet ministers were elected, instead of appointed. How was this carried out in practice? Were they elected by national elections? Was this a good system?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4ftmrf/can_someone_tell_me_about_the_government_of/
|
{
"a_id": [
"d2bvzn8"
],
"score": [
2
],
"text": [
"I am curious to know what the context of this statement was. The Reichschancellor was the one responsible for appointing the cabinet. The constitution of the Weimar Republic for most intents and purposes was essentially the exact same one as the Kaiserreich, with the main exception being that the monarchical position of Kaiser was directly replaced by a democratically elected President. "
]
}
|
[] |
[] |
[
[]
] |
|
2rvmbw
|
Is the acceleration of the universe's expansion a constant? or is it changing with respect to time?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2rvmbw/is_the_acceleration_of_the_universes_expansion_a/
|
{
"a_id": [
"cnjt965",
"cnk46c4"
],
"score": [
12,
2
],
"text": [
"The Hubble parameter, which gives information about the rate of the expansion of space as a function of distance, is not constant. Its time dependence is given by the [Friedmann equations](_URL_0_). \n\nThe reason the Hubble parameter changes with time is because the Hubble parameter depends on the energy densities of the various forms of matter in the universe. Because our universe is expanding, the energy densities of some forms of matter -- specifically dark matter and baryonic matter -- are changing. \n\nHowever, the Hubble parameter is asymptotically approaching a constant value. This is because the dominant contribution to the total energy density of the universe comes from dark energy. Dark energy has a constant energy density. In the limit that time approaches infinity, the dependence of the Hubble parameter on the energy densities is related only to the energy density of dark energy since the energy density of matter goes to zero in this limit. Hence, the Hubble parameter approaches a constant value.",
"If you want a really detailed and specific answer to this question and others such as 'what is dark energy' by the guy (Alan Guth) credited with the early inflation epoch hypothesis that is now accepted cosmology, then [watch this semester's worth of video lectures](_URL_0_). I highly recommend the content of this course - MIT 8.286 The Early Universe."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Friedmann_equations"
],
[
"https://www.youtube.com/playlist?list=PLUl4u3cNGP61Bf9I0WDDriuDqEnywoxra"
]
] |
||
1t7vtd
|
how does the it department handle which sites to block in a corporate environment? (more in comments)
|
Hi all,
I recently landed a job working in a corporate environment, financial industry. Kind of like Office Space, bunch of cubicles everywhere. Anyways I was able to visit reddit all of last week (couldn't load pictures but the comments were okay) but when I came in on Monday this week it was blocked. Could someone please explain how IT finds this sort of stuff? I feel like it was clearly me that ruined everything.
P.S. No Private viewing available, it is grayed-out at work.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1t7vtd/eli5_how_does_the_it_department_handle_which/
|
{
"a_id": [
"ce58i5c"
],
"score": [
2
],
"text": [
"Monitor traffic. Anything not work related, block."
]
}
|
[] |
[] |
[
[]
] |
|
7pbk2n
|
Here in Norway, we eat bread for every meal except for dinner, the only hot meal of the day. I also know that it is different in other cultures, so when and how did this divide happen?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7pbk2n/here_in_norway_we_eat_bread_for_every_meal_except/
|
{
"a_id": [
"dsgzz3a",
"dshd0cx"
],
"score": [
10,
2
],
"text": [
"You might want to try r/askfoodhistorians\n",
"I’m sorry but may I ask you to clarify what you’re asking. Are you asking why Norwegians only have one hot meal a day or why they don’t eat bread with that hot meal?\n\nEdit, or both. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
24jdzz
|
Does bread lose any nutritional value (vitamins, calories, etc) when it goes stale?
|
askscience
|
http://www.reddit.com/r/askscience/comments/24jdzz/does_bread_lose_any_nutritional_value_vitamins/
|
{
"a_id": [
"ch7t7ge"
],
"score": [
3
],
"text": [
"I wouldn't assume so. Staleness is due to crystallization of starch molecules (which is why you should never leave bread in the fridge), and as such shouldn't have an impact on nutritional content."
]
}
|
[] |
[] |
[
[]
] |
||
1xrdkd
|
the reports of people shining lasers in the eyes of pilots, how much of a hindrance is this?
|
I get the basics, someone shines a laser towards a plane, the pilots have problems seeing. I've owned laser pens before and I can't imagine they would have any impact at all on an airplane so I'm assuming they're using some other type of laser.
What types of lasers are we talking about here? How much 'blindness' could they possibly cause? Why would they bother? It's not like the planes are suddenly lurching or that they get any reaction at all. I just don't see the motivation (even to screw with someone).
Edit: And how could they even hit a plane? Planes are huge but it's has got to be hard to direct it at the small window of a plane, flying towards you at a fairly high rate of speed.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1xrdkd/eli5_the_reports_of_people_shining_lasers_in_the/
|
{
"a_id": [
"cfdyhgf",
"cfe3i36"
],
"score": [
2,
2
],
"text": [
"_URL_1_ and _URL_0_ From a small distance it's a tiny red dot. When you aim it at a plane, they see a blinding green image where if caught by surprise can disorient the pilot. This isn't really catching a plane at 30,000 feet. Think of the low flying smaller plane or helicopter. ",
"If the pilot's eyes are dark adapted, he could be dazzled for several seconds.\n\nAlso, some cockpits use a type of glass the scatters laser light, causing the entire windows to light up and become opaque.\n\nAnd while they probably overestimate the dangers, if a pilot was doing something tricky, like trying to land with a crosswind, a few seconds of poor vision could mean a disaster."
]
}
|
[] |
[] |
[
[
"http://youtu.be/e1R4-OD0iWg?t=54s",
"http://www.youtube.com/watch?v=iI7Qq1mYQlI"
],
[]
] |
|
7x5rom
|
How does one wind up buried inside a medieval monastery rather than a cemetery?
|
Hi AskHistorians! I study bones, and this is my first time working on an archaeological group rather than forensic cases. This does not relate to my study, but I’m extremely curious. Why am I seeing people buried inside a monastery rather than the adjoining cemetery?
I’m currently working on a group of skeletons who come from a monastery in Southern France, dated to about 1390 CE from coins. All of these individuals were buried inside the monastery, right along the walls of the church.
Almost all of the graves have multiple people inside, and have evidence of being opened up and having new individuals added. I assumed that since this church functioned as a monastery, it would all be men inside the graves. However, half of the graves are women and or children! The graves are not fancy, they're rock cut and they don't have a marker of any sort (although this could have been lost over time).
Now, there is a cemetery beside the church, and putting graves there seems way more logical than cutting them into the rock of the monastery. Why were these individuals buried inside the church? Why would women and children be in a monastic church?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7x5rom/how_does_one_wind_up_buried_inside_a_medieval/
|
{
"a_id": [
"du68ixw"
],
"score": [
6
],
"text": [
"Amazingly enough, I stumbled across a primary source *yesterday* that answers nearly all your questions here! It's a miracle story associated with Marguerite d'Oignt, a Carthusian prioress and mystical author from southern France who died in 1310.\n\n > It also happened another time that that same Guichard of Ars, the knight, and Monsieur Henri, his brother, a canon from Lyons, went to exhume the bodies of their father and mother, and of some other relatives and friends who had all been buried in the cemetery of Poleteins. They wanted to put them all into a tomb that they had built in the church.\n\n > ...When the moment came when the remains of those who were buried in teh cmeetery were unearthed, the prioress Margaret...handled the bones with her bare hands...In everyone's presence she said that the skull of one of her nuns was missing (she had been the first cousin of Monsieur Guichard of Ars and Monsieur Henri of Ars and had been buried in the same tomb with her father.) And there was no one who knew how many bodies there were in this tomb, not Madame Marguerite nor anyone else.\n\nLate medieval people are well known for zealous, consuming concern for their *own* souls (indulgences/\"buying your way into heaven,\" which isn't actually correct but that's the common understanding today). In fact, lay support for monasteries going back centuries depended as much, perhaps more, on people's concern for their deceased loved ones. The primary *function* of monasteries in medival society was to pray for the dead, and financial donations to monasteries ensured that one's family would be remembered in the daily prayers and Masses of the monks or nuns. Burial inside the church rather than simply in consecrated ground created a more powerful tangible, material connection between humans and heaven.\n\nThus, in this case, Guichard and Henri are mentioned earlier as well known to Marguerite, in charge of Poleteins charterhouse--presumably as financial patrons. They've donated money to the convent for the construction of a family tomb within the church, to hold the remains of numerous friends and family. Some of those bodies were already buried together in the cemetery outside, but which/how many bodies were in the graves was more a matter of speculation than certainty (people know the one nun was buried with her father, but not how many others were with them)."
]
}
|
[] |
[] |
[
[]
] |
|
2dx3ft
|
difference between anarchism and communism
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2dx3ft/eli5_difference_between_anarchism_and_communism/
|
{
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"text": [
"Anarchism is a way of living where everybody decides for themselves how things should be run. There is no government or no bosses to tell us what to do. We make up the rules ourselves.\n\nCommunism is another way of living where there is no money and everything is owned by everybody. People are free to take what they need and everybody works to make lots of stuff so that everybody can be happy and rich.\n\nAnarchism and communism are very similar. Most anarchists are also communists but do not agree with other communists about how we should make communism. Some communists think we should use the government, which anarchists disagree with. Though all communists (anarchist and not) agree that communism is a good idea!",
"If socialism is defined as the broad movement to outgrow/overthrow exploitative economies, then anarchism is a libertarian branch of socialism. As the 19th-century anarchist Mikhail Bakunin succinctly put it:\n\n > Liberty without socialism is privilege, injustice; socialism without liberty is slavery and brutality.\n\nWe can define communism as being a form of socialism which has completely moved beyond markets and commodity production. In Marxist theory, state-managed socialism is considered the first or \"lower\" stage of communism, with full communism emerging as the state itself \"withers away\" (to use ~~Lenin's~~ Engels' phrase).\n\nAnarcho-communism is a tendency within anarchism which favors a full-communist economic system (*edit:* without first transitioning to a state-managed socialist stage). An early proponent of anarcho-communism was the Russian prince/scientist/philosopher Peter Kropotkin. His basic sketch of anarcho-communism, [*The Conquest of Bread*](_URL_0_), is still very readable today.",
"Anarchism (an - without, arkhos - ruler) is a ***political philosophy*** that popped up at the tail end of the industrial revolution. It was a revolt against the capitalist system and (along with some very similar schools of thought) became one of the two major branches of the socialist movement. That branch is called libertarian socialism. Anarchists are [like fraggles](_URL_1_). They drew on enlightenment ideas about liberty and justice and decided that people should all be their own bosses, instead of renting themselves to a class of owners -- the capitalists -- and taking orders from on high. They believe that workers and their communities should control the land, facilities, infrastructure and resources to produce stuff and run an economy, which is the central stated goal of *all* socialists. They want to abolish private property in the means of production **and** the nation-state that enforces it. They believe that \"the people who work the mills should run them\" and that there should be no distinction between \"the government\" and the governed. \n\nCommunism can mean one of four things:\n\n- [a ***stage of history***](_URL_3_) that Karl Marx described as:\n\n - [without state government](_URL_2_) (no sovereigns, no nations, no borders)\n\n - without social class (no economic pecking order)\n \n - without money or property (all work for self and community, take whatever they need)\n\n- a ***political philosophy*** that advocates and wants to advance that stage of history\n\n- (informally) a country *not* in the \"stage\" described above, but where the state is controlled by a (usually) ***\"Marxist-Leninist\"*** political party, which purports to advance communism *through its control of the state*, which itself, at some indeterminate point, is supposed to fade away and disappear\n\n- a synonym for \"fuck you\" when really ignorant and/or stupid people are having an argument\n\nSo, a society existing under the condition (\"stage of history\") of communism is compatible -- if not interchangeable -- with an anarchist society. Not *all* anarchists, though, necessarily advocate *exactly* such a society. Some anarchists may not want (or may not think it's conceivable) to abolish money, even though they do want to abolish class and capitalism (i.e. private ownership of the means of production) in favor of worker cooperatives, community-run nonprofits, other self-governing organizations, etc. \n\nTo sum it up:\n\n- all anarchists are socialists (and no, goofy [recuperation](_URL_0_) like \"anarcho-capitalism\" is not anarchism to anyone except the few clueless American rich kids who call themselves \"anarcho-capitalists\")\n\n- all communists are socialists\n\n- some (probably most) anarchists are communists\n\n- some communists are anarchists",
"They're incredibly similar. Marxism and Anarchism weren't distinct groups until after the First International. The primary disagreement revolves around the \"dictatorship of the proletariat\". Dictatorship of the Proletariat is an incredibly poorly defined and nebulous concept. Both Communists and Anarchists seek to achieve a *classless, stateless and moneyless society* (aka communism). The path to get there is the main disagreement. Marxists believe that the working class can, after smashing the bourgeois state, take control of the state-form to usher in socialism and eventually communism as the state withers away. Anarchists think the state-form is fundamentally incapable of ushering in these changes.\n\nTLDR; Marxist Communists wish to use states to usher in socialism/communism, Anarchist dislike states and wish to usher in socialism/communism through other means."
]
}
|
[] |
[] |
[
[],
[
"http://dwardmac.pitzer.edu/anarchist_archives/kropotkin/conquest/toc.html"
],
[
"http://en.wikipedia.org/wiki/Recuperation_\\(politics\\)",
"https://www.youtube.com/watch?v=5o_U8--_ee0",
"http://en.wikipedia.org/wiki/Stateless_society",
"http://en.wikipedia.org/wiki/Marx%27s_theory_of_history#Communism"
],
[]
] |
||
jpnf1
|
if water can't be compressed in the same manner as air, why do we talk about both air pressure and water pressure?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/jpnf1/eli5_if_water_cant_be_compressed_in_the_same/
|
{
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"c2e3wao",
"c2e8jah"
],
"score": [
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6,
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2,
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6,
3,
2
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"text": [
"Because the deeper you go, the more water presses on you. The more books you place on your head, the heavier the pile on your head is, right? It's the same way with water.",
"Water DOES compress, just minimally. \n\nThe main difference between the two is one is a gas and the other is a liquid. \n\nIn any liquid, the molecules are all close together and don't have much room to compress. In all gasses by comparison, the molecules are MUCH farther apart, allowing room for compression. \n\nSo water does compress, just so minimally you don't notice the size/volume difference as much as the pressure of all the air \"on top\" of it. \n\nFun fact: Air pressure works the same way, where the pressure on the surface of the earth is all the air above you stacked and pushing down. This is why mountains have lower pressure on top, less air stacked above you. ",
"Water pressure doesn't have to do with water being compressed, per se. Due to gravity and all the physical forces between water molecules, any amount of water exerts pressure on any container it is put in. \n\nThink of it this way. When any amount of water is placed on the ground, what does it do? It spreads out as much as it can. When you place it in a jar, it can't spread out...it's in a jar. Instead, it exerts pressure on the walls of the jar because it WANTS to spread out but can't.\n\nWater pressure can also be talked about in terms of moving water from a high container (water tower) to a lower container (your house/shower). The bigger the difference between the two, the more pressure at the lower container. Mostly due to gravity.",
"Pressure isn't about compression. It's about forces applied over a certain area. Take a metal ball and push it against your palm. Now take a foam rubber ball and push it just as hard. If the two balls are the same size, the pressure against your skin is about the same.\n\nAlso, don't forget about DENSITY. Water doesn't get much smaller when squeezed. But we can squeeze air and make it much more dense. For example, pump air into a tank and the tank becomes quite heavy. Air density is normally 1.2 grams for a cubic volume 10cm on a side. That volume of air inside a scuba tank at 200 atmospheres should weigh 200x more.\n",
"Because the deeper you go, the more water presses on you. The more books you place on your head, the heavier the pile on your head is, right? It's the same way with water.",
"Water DOES compress, just minimally. \n\nThe main difference between the two is one is a gas and the other is a liquid. \n\nIn any liquid, the molecules are all close together and don't have much room to compress. In all gasses by comparison, the molecules are MUCH farther apart, allowing room for compression. \n\nSo water does compress, just so minimally you don't notice the size/volume difference as much as the pressure of all the air \"on top\" of it. \n\nFun fact: Air pressure works the same way, where the pressure on the surface of the earth is all the air above you stacked and pushing down. This is why mountains have lower pressure on top, less air stacked above you. ",
"Water pressure doesn't have to do with water being compressed, per se. Due to gravity and all the physical forces between water molecules, any amount of water exerts pressure on any container it is put in. \n\nThink of it this way. When any amount of water is placed on the ground, what does it do? It spreads out as much as it can. When you place it in a jar, it can't spread out...it's in a jar. Instead, it exerts pressure on the walls of the jar because it WANTS to spread out but can't.\n\nWater pressure can also be talked about in terms of moving water from a high container (water tower) to a lower container (your house/shower). The bigger the difference between the two, the more pressure at the lower container. Mostly due to gravity.",
"Pressure isn't about compression. It's about forces applied over a certain area. Take a metal ball and push it against your palm. Now take a foam rubber ball and push it just as hard. If the two balls are the same size, the pressure against your skin is about the same.\n\nAlso, don't forget about DENSITY. Water doesn't get much smaller when squeezed. But we can squeeze air and make it much more dense. For example, pump air into a tank and the tank becomes quite heavy. Air density is normally 1.2 grams for a cubic volume 10cm on a side. That volume of air inside a scuba tank at 200 atmospheres should weigh 200x more.\n"
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[]
] |
||
1s19rb
|
How did Bavaria become a rich region of germany
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1s19rb/how_did_bavaria_become_a_rich_region_of_germany/
|
{
"a_id": [
"cdthx9n"
],
"score": [
2
],
"text": [
"Real scholars and Bavarians would have a lot to add to this but I can give you some ideas. \n\nGoing way back and running all the way up to the present Federal Republic of Germany in which Bavaria is a state, Bavaria has been an independent dukedom, kingdom, electorate and so on, so it's always had the political clout, whether it was an independent kingdom or part of the Holy Roman Empire or the Federal Republic, to make rules that benefited the kingdom, from tax to trade to tolls to whatever they felt was sufficiently within their intererst and power to control to their advantage. \n\nEvery history of a certain period in Bavarian history will give examples of this. As said above, if it's medieval, then it's about getting iron privileges or processing tolls on its roads; if early modern then it's about negotiating with Austria and Prussia about a potential German union; if it's today it's about passing a road tax that's unique within Germany. How did it all happen? Well, it's got great geography and rivers and it's right in the middle of East-West trade. It was very important to the early HRE like Otto I and II who promoted Bavaria up in the feudal hierarchy -- more land = more food = more people = more soldiers. It soon became an independent player, then came the Empire once again and it became a solidly Catholic elector, rich, well connected and placed in Vienna. The story just continues to today. The only thing to add would be Volkswagen, industrialization and Deutsche Bank. "
]
}
|
[] |
[] |
[
[]
] |
||
33wj6a
|
why did i not develop seasonal allergies until well into my 20s?
|
As a kid I never had seasonal allergies, at least not until about 24-25 years old. As an adult they seem to be getting progressively worse each year.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/33wj6a/eli5_why_did_i_not_develop_seasonal_allergies/
|
{
"a_id": [
"cqp17me",
"cqpb95z"
],
"score": [
6,
3
],
"text": [
"I got them after I was pregnant. I was hoping the second pregnancy would take them away again...no such luck ",
"Both your body and the environment change over time. The changing environment is easy to understand (especially if you've moved). The body is just as complex though, and sometimes things \"break\" or new things start due to various factors. Think about acne, arthritis, body hair in new locations, cancer, etc. All these things are due to your changing body."
]
}
|
[] |
[] |
[
[],
[]
] |
|
vjvpu
|
Benefits and Risks of Hydrogen Peroxide
|
My dad has Parkinsons and was diagnosed 5 years ago. Recently we went to a doctor and he advised my dad to use 35% food grade hydrogen peroxide. I would like to know if there are risks/ actual benefits to this.
|
askscience
|
http://www.reddit.com/r/askscience/comments/vjvpu/benefits_and_risks_of_hydrogen_peroxide/
|
{
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"35% hydrogen peroxide is toxic if ingested undiluted. At lower concentrations ( > 3%) it is likely to induce vomiting.\n\nOther than that, all that will happen is it will decompose to oxygen and water, like the other commenter stated. It's not going to provide any benefits for Parkinsons disease.\n",
"A legit M.D. told you to do this? For Parkinson's disease? This is appalling. Hydrogen peroxide is at best a disinfectant and it's internal use got popularized by a stupid book that touts it can cure you of ANY disease (including AIDS, cancer, etc.) when diluted just right. Things like this bother me more than anything and are incredibly detrimental.\n\nI know neurological conditions are daunting, but both you and your father should try and learn as much as possible about PD. I'll give you a crash course and it should make understanding the treatments a bit better.\n\nBasically, your father has a progressive disease where a group of neurons that release dopamine are dying off. So his movement issues are due to a lack of dopamine in a specific area of his brain. The available drugs for PD try to either mimic or replace that dopamine to get to that normal level again. \n\nThe drugs don't prevent the death of dopamine neurons, so the condition worsens with age. Also, it's hard to pinpoint the exact area needed where the dopamine was lost (and at the right level), so you get side-effects (like pretty much every other drug).\n\nPlease find a new doctor (and report the old one), and good luck to you and your father. There are other treatment options, but a neurologist should discuss them with you. This is not a disease that'll go away with quick fixes like hydrogen peroxide, it's a life-long condition."
]
}
|
[] |
[] |
[
[],
[]
] |
|
5xadrf
|
why are most dvd and video game cases still so big?
|
I know that DVD cases were meant to be the size of VHS boxes and then video games followed suit, but no one really uses VHS anymore. Is there a reason DVDs and video games still practice wasteful packaging, especially now that a lot of video game manuals are digital and rarely included in the case?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5xadrf/eli5_why_are_most_dvd_and_video_game_cases_still/
|
{
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"text": [
"1) Marketing - people have been conditioned to look for the DVD-sized case ever since DVDs came out.\n\n2) Theft deterrence - it's harder to fit big things in your pockets. ",
"Stores want the packaging to be large enough that shoplifters can't easily stuff tons of them into their pockets, especially for items like these that are easy to trade for cash at used video game/movie stores."
]
}
|
[] |
[] |
[
[],
[]
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|
4po3c0
|
How did the rivalry between French and German influence the everyday life of people living in Alsace-Lorraine?
|
The country that area belonged to changed frequently, did the people see themself as germans or french?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4po3c0/how_did_the_rivalry_between_french_and_german/
|
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"text": [
"I think it's really important that your provide a timeframe here."
]
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|
[] |
[] |
[
[]
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|
5qjaea
|
Was there rhyming in the Bible originally?
|
There are some parts of the Bible like Psalms, which are mostly songs or poems. They don't rhyme in the currently translated English obviously, but I'm curious if the original, untranslated songs or poems had rhyming in them.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5qjaea/was_there_rhyming_in_the_bible_originally/
|
{
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"text": [
"Not normally, no.\n\nRhyme is predominantly a feature of English poetry. \n\nHebrew poetry, as in the psalms, is marked by other features. These include *parallelism* (including synonymous parallelism, where two lines express a similar or singular idea; antithetical parallelism, where two lines express a contrast; and a whole range of others); possibly *accentual rhythm*, though this is strongly debated; *acrostics* are used in some of the psalms (starting each section with the next letter in the alphabet). \n\nBasically, characteristics of 'poetry' differ from language to language, and period to period (indeed, English poetry was not originally so dominated by rhyme, but by other patterns). \n\n",
"While u/talondearg is not incorrect, the more accurate answer is that we do not have an accurate enough understanding of the actual *phonetics* of Hebrew to be able to make definitive statements about rhyme scheme. \n\nHowever, that said, we do have places where it seems that poetic tools like assonance are at play (Ps 29:9, for example, note the repetitive /ô/ vowel replicating thunder in the Hebrew text), and, elsewhere, alliteration (although no good examples come to mind immediately). \n\nThe best resources on Hebrew poetry are going to be James Kugel (*The Idea of Biblical Poetry*, retired, formerly Harvard prof.), Chip Dobbs-Allsopp (Princeton prof.), and Jackie Vayntrub (currently at Brandeis). "
]
}
|
[] |
[] |
[
[],
[]
] |
|
673o4g
|
Did Peter the Great kill his son Tsarevich Alexei Petrovich? And if he did, why?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/673o4g/did_peter_the_great_kill_his_son_tsarevich_alexei/
|
{
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"He died after extensive torture and two days after he had been sentenced to death; it was less of an explicit chopping off of the head and more of a withdrawal of medical care after he had been repeatedly subjected to the harshest treatment the Russian state could inflict upon a perceived traitor. Keep in mind that this is the same era that considered disembowelment, being dragged behind galloping horses, and hanging as the warm-up to an execution, and not a method of execution in and of itself, and Russia was noted as being particularly brutal by other Europeans.\n\n & nbsp;\n\nAs to the \"Why\"; Alexei Petrovitch was alternately disdained and ignored by his father, who felt that he was the weak offspring of a hated marriage arranged by Peter's mother and the conservative faction that she lead at the time. This consevative faction was later taken over by the intensely conservative and Orthodox Tsarina Eudoxia, Alexei's mother. The breaking point came when Alexei attempted to run away from his responsibilities with his Finnish mistress to his brother-in-law, Emperor Charles VI, humiliating Peter on the international stage. Alexei's return marked the start of an inquisition of the conservative faction that he and his mother lead and that had been a perennial thorn in Peter's efforts to reform the backwards nation.\n\n & nbsp;\n\nTLDR; Alexei was a [Jerry](_URL_0_). Rick (Peter) managed to off him without crashing the Federation this time."
]
}
|
[] |
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16dhs3
|
Photos and the Naked eye
|
All of these photos we see, like of the Pillars of Creation, if we were to be at that point would our naked eye see what we do in the pictures?
The reason I ask is I vaguely remember reading that the photos are a collection of different spectrum all added to one photo.
Update: Thank you for the wonderful (and sort of heart breaking answers.) The question has bothered me for a long time.
|
askscience
|
http://www.reddit.com/r/askscience/comments/16dhs3/photos_and_the_naked_eye/
|
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"Nope. First of all, telescopes cannot take actual color pictures - their pictures are always in grey-scale. In order to create a color picture you have to take pictures through different filters. If you want to have a so-called \"natural color\" image you need to record three images, one in red, one in green and one in blue. Telescope time is extremely expensive and not many pictures are taken with these particular filters because they serve no other purpose but to make pretty pictures.\n\nSo yeah, most pictures of distant astronomical objects like the Pillars of Creation look totally different from what the pictures suggest they look like. Usually the colors are assigned rather arbitrarily to the different filters, for example when the image was shot in infrared or on the frequencies which are common for certain gasses. Additionally, there are also so-called \"representative color\" pictures which, though they are not taken through RGB filters, were colored in a way that we assume the object would look like.",
"Many astrophotographs do, as you point out, compile signals from a large array of the EM spectrum than just visible light. However, some photos do not. Usually, if the photo is nicely documented, there will be some tag saying what you're looking at as far as xray, gamma, radio, etc. or something about the coloring like false-color. From the numerous photos I've noticed that have these sorts of descriptions, many are false-colored but not all. Other ways to figure out these details is to note what telescope has taken the picture. For example, [this APOD photo of Bullet Pillars of Orion](_URL_0_), states the image was taken with the [Gemini North telescope](_URL_1_). It says on the wiki link that \n\n > Each Gemini telescope is equipped with its own version of GMOS, which can perform multi object spectroscopy, long slit spectroscopy, imaging, and integral field spectroscopy at optical wavelengths. Each of the 2 GMOS instruments are currently having their detectors upgraded to Hammamatsu arrays, which will have significantly improved performance in the far red part of the optical spectrum (700 nm - 1,000 nm).\nGemini's silver coating and infrared optimization allow sensitive observations in the mid infrared part of the spectrum (5 - 27 microns). This is covered by T-ReCS at Gemini South, and by Michelle at Gemini North, both of which have imaging and spectroscopic cababilities.\nGemini North has NIFS (Near-infrared Integral Field Spectrograph), built by Australian National University. It takes a 30x30 array of spectra (covering a three-arcsecond-square field) at R=5000 in the 0.95-2.4 µm wavelength range.\nIt also has Phoenix, a high-resolution infrared spectrograph build by NOAO of the United States, although this instrument is no longer offered.\n\nThis still doesn't say exactly what you might be seeing in the APOD pic, but from the information given in both links, I would say that the image is likely enhanced since the infrared part of the spectrum is the telescope forte. The adaptive optics the APOD link mentions is a method to remove atmospheric noise form the image."
]
}
|
[] |
[] |
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[],
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|
9mv23g
|
US Tank Destroyers in the Pacific
|
Did any tank destroyer units serve in the Pacific in WWII and if so what vehicles did the use ex M3 GMC, M10 GMC etc
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/9mv23g/us_tank_destroyers_in_the_pacific/
|
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"There was an initial requirement for 220 tank destroyer battalions, but the troop basis for 1943 called for only 144. Only a maximum of 106 battalions were ever active at one time, and the number required was trimmed to 78 in October 1943. Eleven tank destroyer battalions were converted to other types of units. Twenty-five were inactivated; five in 1943, fourteen in 1944, and four in 1945. The units converted were chiefly trained as amphibian tractor and armored field artillery battalions, presumably because of their previous experience with heavy tracked vehicles. The units inactivated, particularly those in 1944, were given brief retraining as infantry and dispatched overseas as replacements or to depleted infantry divisions for use as fillers. Sixty-one battalions went to Europe, North Africa and the Mediterranean, and ten to the Pacific, one of which was converted after arrival, technically making nine, and counting towards the eleven described above. \n\nThe 627th, 632nd, 637th, 640th, 641st, 670th, 671st, 806th, 815th, and 819th Tank Destroyer Battalions deployed to the Pacific Theater. The 815th, quickly found to be essentially useless in dense jungle warfare (information on this battalion is particularly sparse), was disbanded and its personnel (including noted author Norman Mailer) absorbed by the 112th Cavalry Regiment after a short experience on New Guinea. The 641st was converted to a chemical mortar battalion, and the 627th, 670th, 671st and 806th failed to get into action before the war ended.\n\nM18s served on Okinawa, but curiously not part of any tank destroyer battalions. General Andrew D. Bruce, the original commander of the Tank Destroyer Tactical and Firing Center, ended up in command of the 77th Infantry Division, and managed to secure eight M18s to re-equip the anti-tank company of the 306th Infantry Regiment.\n\n632nd Tank Destroyer Battalion (M10)\n\n > Established 15 December 1941 at Camp Livingston, LA from personnel of the 32nd Infantry Division. Originally a Light Towed Battalion, they shipped from San Francisco, port of embarkation on May. 12, 1942 and arrived in Australia on May 12, 1942. Landed New Guinea on Oct 28, 1943. Landed Philippines on Oct. 20, 1944. The 632nd Tank Destroyer Battalion was, essentially, treated as an organic unit of the 32nd Division. It went to Australia with the 32nd Division. It fought with the 32nd at Aitape and Saidor. It went into the battle for Leyte with the 1st Cavalry Division, but later joined the 32nd on Leyte. On Luzon it was initially attached to the 13th Armored Group but subsequently served with 37th, 44th [*sic*] and 32nd Divisions on Luzon. Unit was deactivated at Camp Stoneman, CA on Jan. 1, 1946.\n\n637th Tank Destroyer Battalion (M18)\n\n > Established December 19, 1941 at Camp Shelby, MS from personnel of the 37th Infantry Division. Originally a Light Towed Battalion, they shipped from San Francisco, port of embarkation on May. 12, 1942 and arrived in Australia on May 26, 1942. Arrived Fiji Islands on June 28, 1942. Unit was attached to the 11th Airborne Div., 1st Cavalry and 37th Infantry Div. Inactivated in Japan on Jan. 25th, 1946.\n\n640th Tank Destroyer Battalion (M5 3-inch gun; to M10 October 1944)\n\n > Established December 19, 1941 at Camp San Luis Obispo, CA, from personnel of the 143rd Field Artillery California National Guard. Originally a Light Towed Battalion, they shipped from San Francisco, port of embarkation on Sep. 4, 1942 and arrived in Hawaii on Sep. 12, 1942. Arrived Guadalcanal on Feb. 5, 1944, New Britain on May 3, 1944 and the Philippines on Jan. 9, 1945. Unit was attached to the 1st Cavalry, 24th, 43rd & 44th [*sic*] Infantry Divs. Inactivated on Jan. 13th 1946 at Camp Anza, CA\n\n641st Tank Destroyer Battalion (n/a)\n\n > Established December 18, 1941, at Ft Lewis, WA, from personnel of the 41st Infantry Division. Originally a Light Towed Battalion, they shipped from the New York port of embarkation on Mar. 4, 1942, and arrived in Australia (via the Panama Canal) on Apr. 9, 1942. Arrived New Guinea on Jan. 21, 1943. Entered combat in May, 1944, and were redesignated as 98th Chemical Battalion (Motorized) on Jun. 24, 1944. Landed in the Philippines on Jan. 9, 1945, and were redesignated as 98th Chemical Mortar Battalion on Mar. 20, 1945. Returned to U.S., landing at Los Angeles Port on Dec 24, 1945. Deactivated on Dec. 26, 1945, at Camp Anza, CA.\n\n815th Tank Destroyer Battalion (various sources list this unit as either having M5 3-inch guns or M10s; again, information is hard to come by)\n\n > Formed on May 11, 1942, at Camp Cooke, CA, as a Heavy Self-Propelled unit. Sailed from San Francisco port on Mar. 10, and landed New Guinea on Mar. 30, 1944. Disbanded on Sept. 27, 1944.\n\n819th Tank Destroyer Battalion (M10)\n\n > Activated on June 1, 1942 at Camp Chaffee, AR as a Heavy Self-Propelled unit. Shipped from San Francisco port of embarkation on Mar. 15, 1944 and landed in Hawaii on Mar. 21, 1944. Landed Palau on Feb. 1, 1945.\n\n**Sources:**\n\nGabel, Christopher R. *Seek, Strike, and Destroy: U.S. Army Tank Destroyer Doctrine in World War II*. Fort Leavenworth: Combat Studies Institute Press, 1985.\n\n[_URL_0_](https://www._URL_0_)\n\nWiggins, Robert P. *Jungle Combat with the 112th Cavalry: Three Texans in the Pacific in World War II*. Jefferson: McFarland & Company, 2011.\n\nYeide, Harry. *The Tank Killers: A History of America's World War II Tank Destroyer Force*. Drexel Hill: Casemate Publishers, 2007."
]
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[] |
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61kotl
|
why are some pale skinned people able to tan easily but others just burn and peel?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/61kotl/eli5why_are_some_pale_skinned_people_able_to_tan/
|
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"It's all dependent on the genes you inherited and the amount of active melanin your body has. Darker skinned people still may experience burning if they inherited that gene, while other lighter skinned people may never burn but have very little active melanin.",
"To everyone in this thread so far: yes we know it's genes. If you don't know more stop guessing and get out",
"The color in skin is from a pigment called melanin. Melanin protects the skin from UV rays in sunlight. Too much UV causes a sunburn. Depending on your genes, you make a mix of eumelanin (brown color) and pheomelanin (red color). The brown blocks UV best. The red can actually make the UV do more damage. Fair skinned people all look pale, but those with more pheomelanin will burn more. ",
"I'm very pale. I don't tan, burn easily or peel. If I do burn, it turns back to white the next day. What's up with that? ",
"Here's something I learned when I was younger when I wanted the best tan of my life (young, unemployed and living in central fl) and I thought was interesting:\n\nThe sun tan actually comes from the UV rays, not the heat of the sun. The heat has nothing to do with it. The UV rays are the strongest between like 10am-3pm meaning that's the best/most effective time to go outside. The UV rays cause your body to produce more melanin to prevent the sunburn. The sun burn is a radiation burn. \n\nI bet most of you already knew this though. I thought it was interesting. ",
"Most of the functional information we have about genes comes from mutational analyses in invertebrates. In fruit flies for example, melanin and pigmentation has been pretty extensively studied. The problem is 2-fold when it comes to humans: first humans can have anywhere from two to four copies of every gene present in the \"blueprint genome\" (the fly genome), because there have been genomic duplications (i.e., duplication of the entire genome) twice throught evolution: once before teleost fishes evolved and once after. So there is a lot of genetic complexity involved. And it's hard to tease apart gene function without mutational analysis, traditionally difficult in mammals with long generation times. The second problem is that skin pigmentation is also tied to metabolic skin function. Vitamin D production for example (critical for calcium absorption). In warmer climates (e.g., most of Africa), skin is exposed to sunlight, and therefore able to utilize the UV irradiation of the sun for the final step of vitamin D production. There's a tradeoff though ---- that extra sun exposure also acts as a strong selection pressure to keep melanin around, to ward off skin cancers (melanin's chief function in the skin). In northern European populations, where climates mean the skin is doing minimal skin synthesis of Vitamin D because the sun disappears abd because clothing protects against cold---- populations have adapted by maintaining lactose tolerance beyond childhood (vitamin D is present in high concentrations in dairy products). And because there is so much less UV irradiation, the selection pressure for maintaining upregulation of melanin disappears. So so far, we are seeing melanin involved in protection against UV irradiation, but it is also involved in dopamine production and metabolism in the brain. So that adds ANOTHER layer of complexity to the puzzle. \n\nIn other words, it's clear that there are a lot of unanswered questions because the complexity of the issue makes it hard to get a big-picture handle on it all.",
"[The Fitzpatrick Scale](_URL_0_) is used by dermatologists to label skin colors. White people, the most prone to burning of all races, can fall anywhere from 1-4 on those charts because of slightly varying genetic backgrounds. So while a person of Celtic background may burn, a person of Italian background may tan because although both people's skin may be light colored, the Celtic person's skin has less tools to deal with the sun once exposure has happened.",
"B.S in Biology but I'll try my best anyways. \n\nAssuming you've read everyone's explanation of how genes play a role, I'd like to explain why these genes are present in certain individuals and answer your question as to why certain individuals burn while others don't. \n\nEvolutionarily, it all comes down to how certain shades helped individuals based on their location. It's beneficial for someone who is closer to the equator to be darker and absorb less sunlight since it's almost always readily available. In comparison to places further away from that center point where sunlight isn't as abundant throughout the day. A more pale complexion would allow you to maximize the amount of sun you take in. \n\nSo if your genes originated from a place where absorbing the maximum amount of sun is best and you're out in the sun for extended periods of time, you'll eventually end up burning simply because that's what the sun does when you have little protection. While others who's genes may have originated from a place with varying degrees of the sun, will be able to tan. That may be why we lose tans in the winter. Evolutionarily, tanning would be to increase your protection against the sun to not burn. The best catalyst for this reaction would of course be prolonged exposure to the sun which would be signaling extra protection needed. You would then lose this tan in the winter, or when you stop being in the sun as much, since you would need to absorb more. \n\nExtra information: Since Humans as a species have been fairly good at adapting as needed, this may explain why we have lighter people in places where it'd make sense for everyone to be darker toned. Things such as umbrellas, sun block and houses would allow those with little natural protection to the sun to easily live in places where it is over abundant. ",
"I live in the Caribbean so I see plenty of sun. I believe it simply has to do with how much sun you take in a given period of time. For example its not the same to sunbathe for 5 hours in one day than 1 hour every day for 5 days. In the second case your skin has time to heal and produce a little melanin before being exposed again. This way your skin cells wont all die causing sunburn. Obviously genetics will also play a factor but this is my experience in what i have seen. I have 100% spanish genetics but i have fairly tanned skin and am exposed to the sun many times a week for short periods and have not sunburned unless i go to the beach on a sunday from 10am to 5 without any protection.",
"I know I'm late but question: is it possible to take a melanin supplement and make it easier for you to obtain and maintain a tan?\n\n\nAsking for a friend. ",
"Who are these \"pale-skinned\" people who tan easily?",
"I also have a pale skin and I just can't burn down no matter how long I sunbath, but I can't tan neither. Why?",
"Having run a tanning salon for 5 years, can tell you it all comes down to your skin type! Each type has successfully more melanocytes (pigment cells) . I'm a type three, black hair, hazel- green eyes and CAUCASIAN+American indian heritage and I tan almost the instant my skin is exposed due to any amount of sunlight hitting the pale melanocytes in my skin - though my legs remain bright white year round unless I work to darken them. I work in my garden every day and by summer's end I'll be very dark usually - though have never had any skin issues and normally use a very cheap Curel skin lotion right after showering. This year for th first time in my life I've seen a couple of old age spot on my mid back - old age barnacles! I removed them at home using Apple Cider Vinegar over a few days period, the skin under was very pale when I got done. Human skin has specific cells place in specific areas where it is most useful to protect your body from UV harm; like faces, shoulders, and back of arms and tops of feet. Imagine the sun shining down directly on you from over your head... each place normally exposed to the direct UV light is where you'll tan or get burned most often. (You don't need special tanning cells under your boobs or between your legs.) So, people tend to work on those areas in tanning salons. Our salon recommends slow steady tanning... a burn is to be avoided, and skin checks are mandatory WE cannot tan anyone under age 18 by state law. \n Skin types: Type one is usually a fair or red head, blue eyes and few freckles and type five is usually negro with almost black skin, brow hair and eyes. \nyes, negro's do go to get tanned, especially if they have low Vit D naturally in their blood.... they need more sunlight than I do to keep my Vit D levels up. Our black ladies would come in if they have a farmer's tan from wearing shirts And shorts in the sunlight and want to be tanned all over EQUALLY. (and IN places where the sun don't shine... I've even done spray tans on these ladies with excellent results on legs, bellies, you name it. Where ever they wanted darker or more even skin. When I ran my salon I had the reputation as doing the best spray tans in the area... my best clients were strippers (we'd minimize some contours by reducing the liquid and maximize areas needed the most - if they had cellulite we'd work on darkening the skin (white skin shows bumps more under stage lights than dark skin) We'd do sample testing to see how much chemical to use (liquid sun tan takes 4-6 hours to develop.) I\"d end up doing spray tans for my clients by appointment only. I even had a few gay guys coming in for spray tans. $50.00 a pop! \nUV radiation penetrates the tissues of our skin and can damage (mutate) the DNA of our cells. Our bodies are usually very good at repairing any DNA damage, but lengthy and regular exposure to UV can cause more damage than the body can cope with. If mutations to the DNA are left unchecked, this may change the way in which the cells behave, and they can become cancerous. this is why we never suggest a person tan over an area that has been burned - it damages it further. \n We also offered a chemical that prevented a burn from peeling! iT's not a secret... you just have to be very careful and proceed very slowly to keep the tan, keeping the skin moisturized to prevent peeling helps. The secret in this is citric acid.(used for canning.) \nI've worked with some type one's using a low pressure bed slowing increasing duration of exposure to the UV bulbs on a daily basis with a \"cold start\" bed and these people slowly were able to get a slight tan without burning. (we also did a UV skin test with them, before starting... putting a sheet of paper with holes on it, slowly exposing the holes one at a time in sequence so that the first hole opened got the maximum time and the last hole only got 30 seconds of UV exposure.) I've seen type one's burn at 2 min's of UV exposure from hand held bulb at 12\" at full blast. \nWe'd have the customers apply a tanning booster to the skin in areas they wanted to be darkest. and a sun block to areas they wanted to protect.\n Even hair can be damaged by UV rays. \n Seriously you know you can still get a tan thru your clothing - if your skin is moist from regular lotion. Dry skin tends to allow the light to bounce off somewhat while tanning lotion promotes the full effect of the UV light. Sun penetrates to the skin at about 35% depending on the fabric. I've gotten burned thru a T-Shirt in the past and had it peel on me within a day or so after I applied an aspirin based topical to the burn area. \n I've had my run-ins with people bad mouthing the tanning industry - but the almighty buck kept my business afloat at that time - I eventually sold the business at double my original costs and took a low pressure bed home with me for occasional use. The money represents my retirement! ",
"This is very interesting! I've always wondered that too because I can go from paper white to dark brown very easily without burning. I tan so quickly, that my body parts are all different shades - my hands are brown, my arms are lighter, my face is pale yellow, and my legs are white. \n\nI don't need to wear foundation but if ever I want to wear face makeup, I have foundation that is considered green/yellow bc any sort of typical flesh tone looks red on me. \n\nI kinda look ridiculous... ",
"Some of us tan and burn and peel the first couple of times every fucking summer. \n\nEither we have to stay tan (after the first burn) to keep the \"shields up\" or we have to stay in shade or use a ton of sunscreen to ease into the tan. "
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fu1rzg
|
products like lysol claim to kill germs. how does it do that?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/fu1rzg/eli5_products_like_lysol_claim_to_kill_germs_how/
|
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"fmabj7h",
"fmabqut"
],
"score": [
3,
5,
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"text": [
"“Germs” can’t survive in high concentrations of alcohol. \n\nCertain cleaners contain anti-fungal or anti-bacterial agents also, which are different chemicals that kill fungus or bacteria. \n\nBleach kills most living cells of anything, so bleach is a widely used “germ killer”. \n\nDepending on the product, it can have different things in it that actively attack and destroy “germs”.",
"Typically it damages the makeup of the organism in some way - breaking down the outer layer, damaging its method of transportation or preventing replication. \n\nLike with the big C right now - it's outer layer is lipids. Fat. Which is why you can defeat it on surfaces with soap and water! The soap breaks down the outer lipid layer.",
"Lysol's (and most of other commercial disinfectants) active ingredient is benzalkonium chloride. Basically, the disinfectants dissolve the lipids in the membrane of bacteria/fungi and in the envelope of the virus, thereby killing the cells and/or inactivating the viral particles.",
"Lysol contains hydrogen peroxide, which is toxic to most things. Hydrogen peroxide releases these things called hydroxyl free radicals which are kind of like little bullets shot at germs. These bullets can damage the cell membrane, which is the protective layer around a virus or bacteria cell, the DNA, which tells the cell how to operate, or really any other part of the cell.\n\nEdit: Not all Lysol's have hydrogen peroxide, some have benzalkonium chloride. This chemical is supposed to work by disrupting the negatively charged part of the lipid bilayer. In simpler terms, the chemical is positive and pulls the negative part of the cells protective coating off, breaking it down. This chemical isn't always effective though and has shown that it is less likely to destroy viruses such as coronavirus than alcohols or hydrogen peroxide."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
1wszs5
|
why were homo sapiens the only species of its kind to prosper, against the neanderthals and other species.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1wszs5/eli5_why_were_homo_sapiens_the_only_species_of/
|
{
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"text": [
"One current hypothesis is that we're a bit better at maintaining extended social networks, allowing for the development of groups beyond the slightly extended family",
"Neanderthals used a method of hunting that required them to get up on the think of it when trying to get their food. A lot of hunters died from the animals they were hunting injuring them. Homo sapiens developed a more ranged style of hunting that protected them from this threat. Of course that's not the only reason. Actually its accepted today that Neanderthals and homo sapiens did interbred. There are people today who still have small amounts of Neanderthal DNA in their overall DNA make up.",
"The book \"Guns Germs and Steel\" (and also the PBS Documentary of the same name - now available on Netflix) does a pretty good job of explaining this.\n\nThe reason why Homo Sapiens took the role we have on this planet was due in a large part to the availability of cereal grains in our native homelands. \n\nWheat and barley grew naturally in the \"fertile crescent\" (modern Iraq/Iran) and rice in middle-Asia, which early Homo Sapiens somehow figured out how to plant and farm. \n\nInstead of relying on the traditional, and inefficient, hunter/gatherer form of food collection, these newly formed societies could farm and store food using only a portion of the population, freeing the other members of the tribe to focus on leadership, tool production, leatherworking for clothing, etc, which allowed them to become infinitely more productive, secure, and well fed, inspiring rapid expansion of the species.",
"It's generally accepted that in places like Europe and Asia, where humans and neanderthals coexisted for some period of time, interbreeding occurred, and that direct descendants of those unions are still alive today. In fact, if you are of European or Asian descent, there is a good chance that between 1-4% of you genetic composition is neanderthal in origin. \n\nAs far as why the modern human genetic mixture isn't more like 50% neanderthal, or even 95%, you might get some clues from the other posters. \n\nAll that being said, there are a couple of other fascinating things to consider when pondering these types of questions. \n\nFirst, it's fairly conclusive that direct descendants of the neanderthal species are alive and walking the earth today, and it's not only likely that you know some of them, it is likely that you are one. \n\nSecond, neanderthals weren't the only \"proto-humans\" who's descendants are still alive today. The [Denisovans](_URL_1_) were stomping around the same parts at around the same time as humans *and* neanderthals, and likely interbred with both, and research has shown that the natives of Papua New Guinea have a genome that is as much as 6% derived from the Denisovans. Part of the reason most people have heard of neanderthals but not the Denisovans is that we have several almost-complete neanderthal skulls and skeletons, while the Denisovans are known primarily from a finger bone and a couple of teeth. \n\nFinally, there is a fascinating story about a [guy](_URL_0_) who found out his y-chromosome was significantly older than any previously recognized by the scientific community. To explain better, almost every single male on earth has a y-chromosome that can be traced back to a common ancestor who lived approximately 200,000 years ago, but in the case of the man in the article, his y-chromosome can be traced back to around 340,000 years ago. What this means is that there was interbreeding occurring between people who had been genetically separated from each other for at least 140,000 years. Further, the man in the article isn't the only person to carry this ancient chromosome, as it can be found in a large portion of the men who live in a small village in Cameroon in Africa. \n\nTL;DR:\n\nYou are not quite as \"human\" as you think you are. You are probably a little bit Neanderthal (or Denisovan).\n\n \n\n"
]
}
|
[] |
[] |
[
[],
[],
[],
[
"http://www.newscientist.com/article/dn23240-the-father-of-all-men-is-340000-years-old.html#.Uu5zcfldWWQ",
"https://en.wikipedia.org/wiki/Denisova_hominin#Interbreeding"
]
] |
||
35w1b6
|
what exactly is turbo?
|
I know it has something to do with taking your exhaust and feeding it back into the engine somehow, and that it gives you more horsepower.
But how exactly does this work?
Also, does it make the car more efficient as a whole, such as by giving you more MPG? Why don't all cars have it, if this is the case? Is the only downside cost?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/35w1b6/eli5_what_exactly_is_turbo/
|
{
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"cr8ckjb",
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"text": [
"Your engine requires oxygen to burn the fuel. The thinner the air that your car is breathing, the less oxygen is being fed into the engine and the worse the car will perform. A turbo works like the big fan at the front of a jet engine, and serves to cram and pressurize the air that is being ingested in to the intake to make it \"thicker\", so to speak, which improves performance.",
"A turbocharger is a exhaust driven gas turbine. Your engine works by sucking in oxygen rich air, adding fuel, compressing it and sparking it to make an explosion. The more oxygen is in the charge, the more fuel and more bang comes out.\n\nA turbocharger use hot exhaust gas to spin a turbine to suck in more air than the engine normally can, compressing it, then provide it to the engine.\n\nTurbochargers provide more power when power is needed. At great cost to fuel efficiency. Turbos don't add mpg when you're cruising at light load. They improve power when you're at med to high load, like when accelerating.",
"A turbocharger is a device which uses exhaust gases in an engine to power a fan (turbine) which pressurizes air and pumps it into the intake of a car. A turbo does not feed exhaust gases back into the car, but rather takes advantage of the otherwise wasted energy of high pressure exhaust gases.\n\nAt low pressures, a turbo can help an engine 'breathe' and use that otherwise wasted energy to make power more efficiently. But at higher pressures, it increases performance at a cost of efficiency. This is because a precise amount of air and fuel must be delivered into a combustion chamber, or gasoline won't explode properly. More air into the engine means more fuel is needed to maintain that ratio, which amounts to a lot more power but also a lot more fuel.\n\nTurbos are prone to breaking, add complexity and cost to an engine design and can potentially wear an engine out faster. If a non-turbo engine (naturally aspirated) can make the target power and efficiency without it, manufacturers often opt for not adding one.\n"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
76jtys
|
I gather that Papal Indulgences were first issued during the Crusades to essentially "give last rites in advance" to Christians likely to die far from a priest. Is this right, and how did this turn into the "buy your way out of purgatory" scheme that Martin Luther criticised?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/76jtys/i_gather_that_papal_indulgences_were_first_issued/
|
{
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"text": [
"A further question: Did any Priests or significant religious figures follow the armies of any Crusade, to act as a rallying of support, to organize things like Mass, etc., or to deliver the aforementioned rites to dying?",
"I can't comment on the development of the sale of indulgences in anywhere near enough detail to answer the second part of your question, but I can provide some context to the first. \n\nFirstly, the idea that crusaders would die far from a priest is absurd. Many priests went on the First Crusade. Most of our eyewitness accounts of the crusade were written by priests. Fulcher of Chartres, Raymond of Aguilers, and Ralph of Caen were all definitely priests, while the anonymous author of the *Gesta Francorum* has been widely debated but was probably also of some sort of religious background. There were also numerous papal legates (think ambassadors...but more medieval) joined the crusade with Bishop Adhemar of Le Puy taking on a prominent leading role. This is to leave aside the many personal clerics and confessors that major nobles would have brought with them (Raymond of Aguilers was actually attending as a cleric to Raymond of Toulouse, one of the crusade's leaders). There were priests a plenty, is my point. \n\nAs to the beginnings of the indulgence as part of the First Crusade...that's a little more complicated. A lot has been written on this topic by theological scholars, and there are aspects of the debate that go totally over my head, so I'll try and keep this simple. Just understand that there is a lot of nuance and discussion that is being cut out here for the sake of simplicity and comprehension. \n\nWe have multiple accounts of the Council of Clermont where Urban II announced the the First Crusade, but none of them are 'official' per se, meaning here that they are written by the papacy. The two primary chronicle accounts we have are Fulcher of Chartres and Robert the Monk. There has been a lot of debate about which one is more accurate. Their accounts agree on most of the big points, but have a lot of differences in the details. Most likely both of them are embellishing or omitting points that they don't like, and the truth is a third option, but they're what we have to work with (well...them and a few minor bits of supporting evidence we won't be covering here). \n\nFulcher of Chartres has Urban II say that anyone who dies while on the crusade will be given a 'remission of their sins', while Robert the Monk has him say that anyone who goes on the crusade will receive the remission. The difference between remission of sins and indulgence has been debated on and off in theological circles, my rough understanding of it (it's some pretty nuanced stuff, and I am not a theological scholar) is that indulgences were slightly better. Basically, if you think of sins like crimes, and indulgence is a complete wiping of your record, while a remission is more like a pardon: you are exempt from the punishment for your crime but you are still recorded as having been guilty of it in the past. There has been a convincing recent argument that whatever the theological nuances of this debate, it's hard to show that actual crusaders would have appreciated the difference, and many might have thought they would get indulgences regardless of official church rhetoric. I will not here that later crusades, particularly the Second Crusade, began a practice of giving out full indulgences to anyone who went. \n\nIt is also worth considering here some of the context of the First Crusade. The crusade was partly inspired by the practice of pilgrimage. The task of going on a pilgrimage was a common penance assigned to sinners during confession, and the pilgrimage to Jerusalem was the biggest and most important of the lot. If you did something really bad, the pilgrimage to Jerusalem was the ultimate task to make up for your sins. The crusade was envisaged in part as a new sort of pilgrimage. Traditionally you were supposed to go on pilgrimage unarmed, so the crusade was a sort of armed pilgrimage. In this context, anyone participating on the crusade could be seen as undertaking a pilgrimage to Jerusalem, which would involve a remission of all of their sins under normal circumstances. So while the arming of pilgrims was a fairly revolutionary idea, the fact that crusaders would be given exemption from their past sins was perhaps a lesser change, and not entirely unexpected. \n\nSources: \n\nChristopher Tyerman (ed.) *Chronicles of the First Crusade*\n\nChristopher Tyerman *How to Plan a Crusade*\n\nThomas Asbridge *The Crusades*"
]
}
|
[] |
[] |
[
[],
[]
] |
||
3k7k25
|
Were Christian women in Europe expected to wear veils for religious reasons? If so, when did the custom decline?
|
It's mentioned in the Bibile that women should cover their heads when praying, and it seems that Catholic nuns do veil themselves. I heard that a century or two ago, women in Europe, especially Southern Europe, commonly wore veils in public for religious reasons like many Muslim women do today. Is that true?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3k7k25/were_christian_women_in_europe_expected_to_wear/
|
{
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"cuve4uz",
"cuvvez7"
],
"score": [
54,
4
],
"text": [
"At one point all women were required to cover their head for church. In general unmarried women were not obligated to cover their hair if they were not in church. Married women during the medieval era often cover their hair until the the custom completely died off sometime during the Renaissances depending on the country. A common headcovering for married women was the [wimple](_URL_1_), this is where nun's headdress derived from. King James version of Isaiah 3:22 even stated *The changeable suits of apparel, and the mantles, and the wimples, and the crisping pins*. Around the mid-1400's [transparent wimple](_URL_2_) appeared to show hairstyle underneath. After the 1500's there were many more varieties of head covering available. ~~For example the book *Inside the Wardrobe of Anne Boleyn* described unmarried Anne Boleyn loved to wear her long hair loose~~, but after she married Henry VIII she was obliged to cover her hair. She often wore [French hood](_URL_0_) that didn't cover all the hair completely. After Elizabethan era there seem to be no major difference between headwear of married and unmarried women in Western Europe except for public worship in some denominations. \n\nIn Eastern Christian denominations women were often required to cover their head in church (even today). ",
"You may find this post interesting\n\n* [Why did medieval women wear headscarves? Was it simply fashion, or were they worn for reasons of modesty/morality?](_URL_0_) - featuring u/itsallfolklore"
]
}
|
[] |
[] |
[
[
"http://speedy.theanneboleynfiles.com/wp-content/uploads/2009/11/anne_boleyn-231x300.jpg",
"https://gafava.files.wordpress.com/2008/06/19-wimple.jpg",
"https://upload.wikimedia.org/wikipedia/commons/3/36/Rogier_van_der_Weyden_Portrait_of_A_lady_C1460.jpg"
],
[
"https://www.reddit.com/r/AskHistorians/comments/2heb8s/why_did_medieval_women_wear_headscarves_was_it/"
]
] |
|
4szxr3
|
how is .99 repeating a rational number?
|
My understanding is that for a number to be rational, it needs to be able to be represented as a fraction, and that all repeating decimals can be represented as (repeating portion)/(same number of 9's).
.99 repeating would then be 9/9, which is 1. I don't understand how it can still be concidered a rational number
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4szxr3/eli5_how_is_99_repeating_a_rational_number/
|
{
"a_id": [
"d5dh0se",
"d5dh5or"
],
"score": [
3,
6
],
"text": [
"I don't really understand the question. As you said yourself, .99 repeating can be represented as 9/9. Since it can be represented as the ratio of two integers, it's by definition a rational number.",
"It's a little funky, but the answer is the 0.999 repeating [*is* equal to 1!](_URL_0_...).\n\nThere are various ways to prove this, ranging from simple algebra to more complicated series and limits, but the simple fact is that 0.999(repeating) is equal to 9/9 which is equal to 1, and those are all just different ways of writing the same (rational!) number."
]
}
|
[] |
[] |
[
[],
[
"https://en.wikipedia.org/wiki/0.999"
]
] |
|
blgfki
|
why can't soiled cardboard be recycled?
|
I know that in the process the oil floats with the paper pulp and can't be separated which creates poor quality paper. My question is more specifically, why is there no chemical or physical process that can be used to separate the two? Is it a lack of innovation, a cost prohibition, or something else?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/blgfki/eli5_why_cant_soiled_cardboard_be_recycled/
|
{
"a_id": [
"emofw0o"
],
"score": [
2
],
"text": [
"Separating and extracting the oil from the pulp requires too much effort and has too many risks for the crew and the facility (oil and food contaminants attract pests and bacterias).\n\nI assume it is more cost effective to trash the oily batch and use it for composting..."
]
}
|
[] |
[] |
[
[]
] |
|
m36ss
|
how mma fighters can cut over 20 pounds in a day
|
i think a lot of it is water weight but TWENTY pounds?! it's crazy.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/m36ss/eli5_how_mma_fighters_can_cut_over_20_pounds_in_a/
|
{
"a_id": [
"c2xq4fk",
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"c2xrfow",
"c2xq4fk",
"c2xqqrx",
"c2xrfow"
],
"score": [
2,
5,
7,
2,
5,
7
],
"text": [
"You're body is something like 60% water. If you significantly dehydrate yourself, then shed as much weight as possible, shit, piss, sweat etc, you can lose a significant amount of weight",
"When I was competing, I cut no more than 7-10 lbs for a fight. A few techniques I used were cutting carbs out of my diet, running with a sauna suit, and sitting in a steam room. Also, I would normally do this over several days up to a week, not one day.\n\nAlso, it's all water weight. Once I made weight, I would fill up on carbs, drink a shake, and maybe some pedialyte that night, and I would be right back where I was by morning.",
"I was with a camera crew that followed around WEC/UFC fighters for a couple days up to the fight and we interviewed them while they were trying to cut. Their corner men do everything for them (bringing them the remote control in their hotel room, carrying their bags, etc) because they aren't eating or drinking (more than *absolutely necessary*) and are understandably weak. In another room we were in, one guy was wrapped in plastics and doing jumping jacks with his people until he gave out, and when he went to the floor, everyone swarmed him, rubbing him so that he still continued to sweat even if he could no longer work out. It was surreal.",
"You're body is something like 60% water. If you significantly dehydrate yourself, then shed as much weight as possible, shit, piss, sweat etc, you can lose a significant amount of weight",
"When I was competing, I cut no more than 7-10 lbs for a fight. A few techniques I used were cutting carbs out of my diet, running with a sauna suit, and sitting in a steam room. Also, I would normally do this over several days up to a week, not one day.\n\nAlso, it's all water weight. Once I made weight, I would fill up on carbs, drink a shake, and maybe some pedialyte that night, and I would be right back where I was by morning.",
"I was with a camera crew that followed around WEC/UFC fighters for a couple days up to the fight and we interviewed them while they were trying to cut. Their corner men do everything for them (bringing them the remote control in their hotel room, carrying their bags, etc) because they aren't eating or drinking (more than *absolutely necessary*) and are understandably weak. In another room we were in, one guy was wrapped in plastics and doing jumping jacks with his people until he gave out, and when he went to the floor, everyone swarmed him, rubbing him so that he still continued to sweat even if he could no longer work out. It was surreal."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
|
2syrkm
|
why can the us postal service be given responsibility for the delivery of our mail, but when it never shows up just say "well we scanned it delivered so you'll have to talk to the seller" and not actually have repercussions?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2syrkm/eli5why_can_the_us_postal_service_be_given/
|
{
"a_id": [
"cnu3jr0",
"cnu3nc2"
],
"score": [
2,
3
],
"text": [
"If you didn't pay for package insurance, there's not really much they're obligated to do. It's not their job to ensure the physical security of a package once it's delivered unless you've paid for additional services.\n\nThe post office just takes a note of a missing package. If there's a large number of missing packages in a particular area or a suspicious number of missing packages associated with a missing postman, that might trigger an investigation but when they're delivering hundreds of millions of pieces of mail per day, a single missing package is hard for the to justify putting any effort into.\n\nAs for the shipper - it's just the cost of doing business. Insurance & delivery confirmations are cheap - if they don't want to eat the cost of a missing/misdelivered package, they should be paying for extra security.",
"Well, they're not responsible to *you* because they don't have a package to deliver to you. They can't magically make one appear.\n\nThey *are* responsible to the person who shipped the package, if the person who shipped the package paid for mail insurance. But most shippers would rather pay less for mailing and handle the risk of a lost package on their own, so the postal service doesn't provide it by default."
]
}
|
[] |
[] |
[
[],
[]
] |
||
fh7b0u
|
How much Ancient Greek philosophy originally came from Egypt?
|
I’ve read that the Greek philosophers that we know of as the “fathers of philosophy” (Socrates, Plato, Aristotle, etc.) actually got many of their ideas from the Ancient Egyptians. How much truth is there to that?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/fh7b0u/how_much_ancient_greek_philosophy_originally_came/
|
{
"a_id": [
"fkb42sh"
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"text": [
"#**Part I**\n\nHi!\n\nDo you have a specific source in mind? I mainly ask because it is sort of a strange claim to make with respect to Socrates, Plato, or Aristotle. The preeminent influences on those thinkers were, first and foremost, each other. Further back, they are reacting above all to the Sophists, the Eleatics, the Pythagoreans, Anaxagoras, and Heraclitus. Now, there are some more promising candidates for Egyptian or Near Eastern influence on Greek thought, but they are earlier figures. One such exception might be Near Eastern mathematics or astronomy. Or perhaps the influence of myth on the traditional ways of thinking that philosophers reacted against? Though in these latter cases it must be said that it is far more Hesiod and Homer than anything from the Near East that bears mentioning. Think, for example, of the (in)famous passage in Republic in which Plato’s Socrates argues for censoring Homer to remove the “bad” parts!\n\nLet’s start at the beginning, with Thales of Miletus (~624-546 BCE), who is often taken to be the first of the Greek philosophers. Although we don’t know much about him, we do know that Aristotle (Metaphysics 1.3, 983b18-27), writing hundreds of years later, considered Thales to be engaged in the same basic philosophical project as he was (unlike, say, Hesiod). Thales was famous for lots of things, one of which was the prediction of an eclipse. This prediction is reported to us by Herodotus:\n\n > As they were having equal success in the war, it happened that in the sixth year, when a battle was being fought, the day suddenly became night. Thales of Miletus had foretold to the Ionians that this loss of daylight would occur, setting as a limit the very year in which the event occurred. (Histories 1.74)\n\nThere is some speculation that, *if* Thales actually made this prediction (Herodotus is not always a sure guide!), that he did so based on Babylonian techniques. The thought here is that Thales did not have the requisite astronomical knowledge to predict the eclipse in anything like the way a modern astronomer would. Babyolians, however, had been keeping meticulous records of eclipses for a very long time and patterns in these observations would be sufficient to allow for a very rough estimate to be made of when an eclipse would occur. This is a plausible suggestion in a couple of ways. First, it jibes with the rough nature of the prediction that Herodotus reports (“setting as a limit the very year”). Second, it isn’t implausible that Thales could have been exposed to Babylonian astronomy, living as he did in a Greek colony on the coast of what is today Turkey. \n\nI myself incline toward the view that this attribution is spurious, however. The trouble is that it doesn’t seem possible that Thales could have used Babylonian astronomy to have predicted *where* the eclipse would occur even if he could roughly determine *when* it would occur. Nor could anyone else, to my knowledge, prior to Ptolemy’s Almagest in the second century CE. So, I think something about Herodotus’s account must be incorrect. On this, see McKirahan(2010, pp.23-25). Probably, Thales was a well-known sage who was genuinely interested in astronomy in general and eclipses in particular and Herodotus, in the interest of telling a good story, plays fast and loose with the facts. There is, however, some reason to think Thales may well have known that solar eclipses were caused by the moon coming in-between the earth and the Sun:\n\n > Thales said that the sun suffers eclipse when the moon comes to be in front of it, the day in which the moon produces the eclipse being marked by its concealment (Aristarchus, Commentary on Homer’s Odyssey, 53.3710, col. 2, 37-40).\n\nThe “concealment” here seems to refer to the moon, and thus to refer to the new moon. The inference would then be from the phases of the moon, the position of the moon in such phases, and the occurence of solar eclipses. None of that is particularly outlandish for a thinker in Thales’s time and place to have figured out, and it would amount to Thales having identified a necessary (but, importantly, not sufficient) condition for the occurence of an eclipse.\n\nSo much for eclipses. A connection has also been suggested between Egyptian myth and Thales’s material monism, his thesis that everything is ultimately one single type of thing. This proposed connection dates from Antiquity:\n\n > Aristotle speaks quite strongly against this view [Thales’s material monism], which was prevalent perhaps because the Egyptians recounted it in mythological form and Thales may have imported the doctrine from there. (Simplicius, Commentary on Aristotle’s De Caelo, 522.16-18)\n\nNote the contrast here between Aristotle and Thales and the Egyptians. Aristotle is presented (correctly) as not engaging with the Egyptian view as a genuine rival, but rather only with Thales’s philosophical version. The idea seems to be that Thales was alive to an option because it was presented, in mythological form, in Egyptian tradition and that, as it turned out, he thought there was something philosophically defensible (read: true) about that view. But Thales gives an argument for this position, at least as Aristotle understands him, and it is on that argument and that argument alone that the philosophical view rests. We can think similarly of philosophical defenses given today for the existence of God by some theists. Alvin Plantinga is a Christian, but when he argues in *Nature of Necessity* for the existence of a maximally great being he rests that case entirely on his modal ontological argument. The idea is that his religion says something that happens to be both true and that can be rationally established to be true. (Nevermind if he is right about that, the point is just that the distinction between the religious and philosophical statement of a thesis differ in justification even if not in content). Anway, back to Thales. Here is his argument.\n\n > However, they do not all agree about how many or what kinds of such principles there are, but Thales, the founder of this kind of philosophy, stated it to be water… He may have got this idea from seeing that the nourishment of all things is moist, and that even the hot itself comes to be from this and lives on this (the principle of all things is that from which they come to be)... getting this idea from this consideration and also because the seeds of all things have a moist nature; and water is the principle of moist things. (Aristotle, Metaphysics 1.3, 983b18-27)\n\nFirst, note how tenative Aristotle is about Thales’s view! Perhaps, even in Aristotle’s day, Thales was an obscure figure. Aristotle had the premier library of his day, which makes the fact that it seems he isn’t quite sure what Thales said even more surprising. On Aristotle’s library, see Casson (2002, pp. 28-29). Be that as it may, Thales’s argument is illuminating. Here is one way to reconstruct it:\n\n1. That from which everything comes to be is that which is ultimately fundamental\n\n2. Water is that from which everything comes to be\n\n3. So, water is that which is ultimately fundamental\n\nA couple things. First, Thales’s view is ambiguous. Does he want to say that everything is, appearances to the contrary, literally water? Or does he rather want to say that everything comes from water? Both readings seem live. Whichever reading is correct, however, the view strikes us all as silly. And silly it is, because it contains an obviously false, empirically motivated premise, namely (2). Now, this premise probably wasn’t crazy to Thales, given the limited empirical evidence he had. But, and this is part of what is distinctive about Greek philosophy, consider the other premise, (1). That looks interesting and plausible, even today! I invite anyone reading this to consider for themselves whether or not they think it is true. That this invitation is not ridiculous in the way inviting you to consider whether the Egyptian myths that possibly served as an inspiration for Thales’s material monism strikes at the heart of why I’m so hesitant to attribute any full-blooded *philosophical* influence to the Egyptians in such cases."
]
}
|
[] |
[] |
[
[]
] |
|
bup8zr
|
why is it that people hate waking up even after getting 7-9 hours of sleep?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bup8zr/eli5_why_is_it_that_people_hate_waking_up_even/
|
{
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"text": [
"The whole \"get 8 hours of sleep and you'll be fine\" is a myth(but still a good rule to live by). Genetically, everyone has different sleep needs. Some may feel fine after 5 hours, where some will feel groggy waking up after 9.",
"It depends on what phase you wake up in during your sleep cycle. If you finish your 90 minute sleep cycle and wake up around then, even if it’s only been 3 hours, you won’t feel as tired as of you wake up in the middle of your REM cycle, even if you have already slept 7+ hours. \n\nAlso some people need more sleep than others or are on a different sleep cycle (variations of naps during the day and less time at night)",
"People hate waking up because they dread what is to come that day. I realized that I love waking up after changing careers, and hated waking up when I was stuck at my other job. That is why waking up on the weekend feels better than waking up on a workday."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
6x00pg
|
How can we estimate the moment magnitude number of an earthquake that we know occurred, but have no direct measurements of?
|
What I mean is, when someone in say the thirteenth century wrote down that an earthquake occurred in his hometown on a specific date, can we look into the geological data and maybe estimate the strength of this earthquake?
|
askscience
|
https://www.reddit.com/r/askscience/comments/6x00pg/how_can_we_estimate_the_moment_magnitude_number/
|
{
"a_id": [
"dmcfyx4"
],
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"text": [
"When dealing with historic earthquakes, we often rely on the [Modified Mercalli Intensity scale](_URL_3_), which classifies earthquakes on the basis of the intensity of it's felt effects (e.g. damage, etc) as opposed to the [moment magnitude scale](_URL_1_), which is a direct measure of the energy released in an earthquake. There are [rough conversions](_URL_2_) between intensity and magnitude, but a lot of things can influence intensity. Things like the depth of the earthquake (shallower earthquakes will generally produce more intense shaking than deeper earthquakes of an equivalent moment magnitude) or the specific geology of the region experiencing the earthquake (is there a lot of loose sedimentary rocks within a basin that may allow seismic waves to reverberate, etc). There's also the challenge of dealing with often inconsistent reports in historic records and having to account for local building practices, etc.\n\nIn some cases, the ruptures associated with specific historic earthquakes have been investigated with various paleoseismological techniques (e.g. trenching across faults to measure offsets, mapping rupture dimensions, etc) allowing for slightly better estimations of the moment magnitude of said events. There are some notable examples of this, a good example is work done along the frontal Himalaya to find ruptures associated with large historic events, [e.g. this paper and others like it.](_URL_0_)."
]
}
|
[] |
[] |
[
[
"http://www.nature.com/ngeo/journal/v6/n1/full/ngeo1669.html?foxtrotcallback=true",
"https://en.wikipedia.org/wiki/Moment_magnitude_scale",
"https://earthquake.usgs.gov/learn/topics/mag_vs_int.php",
"https://earthquake.usgs.gov/learn/topics/mercalli.php"
]
] |
|
28lcme
|
Was there a Palestinian independence movement before the formation of the modern state of Israel?
|
Did the Palestinian people (from any time since the arrival of Islam) ever try to break free from the various empires and kingdoms that controlled the Levant? When did the Palestinian identity emerge?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/28lcme/was_there_a_palestinian_independence_movement/
|
{
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"text": [
"The short answer is overwhelmingly *yes*. However, the formation of the identity, and how strong it was before the 1948 Israeli Declaration of Independence, is still a hotly contested issue today.\n\nTo give you some background on why that is, the question of \"Palestinism\", or Palestinian nationalism, is extraordinarily relevant to Israel's negotiations over the \"right of return\" for refugees of the 1948 war. The question of how distinct the area felt itself to be also creates an idea that Israel fears: namely a justification for a Palestinian state where Israel is today. This fear was much more pronounced following 1948, and Israel (and Jordan) undertook efforts to educate Palestinians within their borders on how Palestinism was a recent invention. I'll expand on this later.\n\nIn order to understand the Palestinian independence movement, I'll break this up into 3 parts: pre-WWI Palestinism, post-WWI Palestinism, and post-1948 Palestinism.\n\nThe phrase Palestinism is one I've read only in a few works, and is really just an ad-hoc word to simplify things. If you haven't heard the word I completely understand, just be aware I'm referring to \"Palestinian nationalism\" in the sense of a Palestinian independence movement, like your question asks!\n\n**Pre-WWI Palestinism**\n\nThis portion begins with an examination of where Palestinian identity really began to form, and where the word \"Palestine\" even comes from. One of the earliest, if not the earliest, recorded occurrences of the phrase is under the Roman empire, as *Syria Palaestina*. The Romans divided the area into Palaestina Prima and Palaestina Secunda, according to Gerber. This division, done after the revolt of Bar Kochba in 132 AD (where the area was regained by Jews for 3 years, before being lost again to the Romans) is where most people derive the name \"Palestine\" from. Previous derivations go back to the Philistea, a name given by Greek writers to the area where the Philistines lived, between Tel Aviv and Gaza.\n\nThe phrase, while existing as an administrative district under the Romans, appears to have gone out of style in government after the Arab empires went out of fashion themselves. As Gerber notes:\n\n > The term Jund Filastin or “the administrative region of Palestine” was current in Arab parlance from some time after the establishment of Muslim rule in the Fertile Crescent in the mid-seventh century until 1250.\n\nAfter this, real administrative use of the term \"Palestine\" was not made until far later, hundreds of years forward in history. However, references to \"Palestine\" were still made, during the duration of the Ottoman Empire.\n\nIt's important to note that at no point did the groups of people living on the land seem to sociologically consider themselves \"Palestinians\" and try to rebel. The Bar Kochba revolt was done to re-establish *Judea*, one of two Jewish kingdoms of antiquity (the other being Israel). Palestinians did not appear to identify as \"Palestinians\" alone, and placed more root in their Islamic, or Arab, culture (or both).\n\nDuring the Ottoman Empire, where our story picks up now, the area of \"Palestine\" as we understand it was divided into three, and separated from Syria. Harms explains:\n\n > Into the late-Ottoman years, Palestine was not a singular administrative geopolitical entity. Its organization changed over the course of the nineteenth century, but by the end of the century it was divided into three districts, or *sanjaks*: Jerusalem, Nablus, and Acre, all of which had been a part of the *vilayet* (governorate) of Syria.\n\nIn 1887, Jerusalem was made its own *sanjak*, and those of Nablus and Acre were transferred to the new *vilayet* of Beirut. So Jerusalem, which was a district not pertaining to any governorate, answered directly to the Ottoman central administration in Istanbul and had control over the south of Palestine as we know it. It is important, again, to note that the Ottomans frequently referred to the general area as *Arz-i-Filistin* (the \"Land of Palestine\") in correspondence.\n\nAgain, however, there is no real *independence* movement that came up in the early Ottoman period. Sociologically, however, the people of the area had already begun to call themselves \"Palestinians\" in a sense, as far as we can tell from cultural references. Mujir al-Din al-Hanbali al-Ulaymi, a resident of Jerusalem who wrote a history in 1490 of the area, used the term \"Palestine\" quite often in his work, and does so as a reference to the country he lives in. This is not to suggest that Palestine was a *separate* country, because it was not, but he understands the general area to have been Palestine, creating an inherently obvious link sociologically between how Palestinian identity considered itself back then. Khayr al-Din al-Ramli, who lived in al-Ramla in the mid-17th century and was a mufti and legal scholar, wrote Islamic legal discussions of questions posed by members of the public, called *fatwas*. A prominent writer, his works were cited quite often, as fatwas were public and supposed to be used by others. He, too, calls his country Palestine, and uses *biladuna* (our country) as well in his writings, suggesting that Palestine was definitely recognized as an area that people lived in, though not a governmental one.\n\nAgain, however, under the Ottomans there was not really a *Palestinian* independence movement. Typically the movement, at least pre-Mandate and pre-Zionism, rested on Arab nationalism. During the first World War, this Arab nationalism (pan-Arabism) was utilized by the British through Faysal Husayn to organize the Arab Revolt against the Ottoman Empire. The promises made to Husayn still cause a lot of problems today, and are the root of Arab grievances against the British as far as Palestine goes.\n\nThere is also a sentiment that Palestinian \"states\" had existed in the past. The best example of this is the principality in the area of the Galilee controlled for several decades until 1775. A family of Bedouin tax collectors called Zaydan built the principality under the Ottomans, under the ruling head Dahir al-Umar. In the 20th century, an anthropologist found that 20th century Palestinian peasants in the Galilee appear to have considered Dahir al-Umar as presiding over a Palestinian \"state\", but this was not independent of the Ottomans and the anthropologist's results have not been rigorously tested as we do today in most sociological studies.\n\nThe phrase Palestine, as far as modern usage, seems to have been brought up in an independence-movement sense by *Filastin* (Palestine, basically), a newly established newspaper founded by Isa al-Isa in 1911. *Filastin* was a prominent critic of the Ottoman government over how it perceived the Ottomans handling the Zionist movement.\n\nPre-WWI, the basic idea however was not to create a Palestinian state, but to create a pan-Arab one. This was the idea that led Faysal Husayn to organize the Arab Revolt against the Ottomans during WWI with the help of the British, and seems to have been the prominent ideology at the time among all others, at least before the war itself. Ottomanism and Islam were the prominent identity-builders, according to Khalidi, before WWI happened. However, Islam/Ottomanism stopped being the primary identifying factors early in the 20th century. As Khalidi puts it:\n\n > ...the decline of religion as the governing principle of the Ottoman state in the waning years of the Empire, and what was perceived by many as the cynical exploitation of Islam by the highly secular CUP from 1908 to 1918, accelerated a decline in the saliency of religious identification in the Empire before and during the War. This complemented and enhanced a growing shift to secularism and secular nationalism on the part of some of the younger segments of the Ottoman elite, but this shift was by no means as definitive as the eclipse of Ottomanism.\n\nThe main identifying factor, then, became a vacuum. Over time, this vacuum was filled by both pan-Arabism (which died out quickly), and by Palestinism.\n\nKhalil al-Sakakini, the co-founder of the al'Madrasa al-Wataniyya school in Jerusalem, said in 1925:\n\n > A nation which has long been in the depths of sleep only awakes if it is rudely shaken by events, and only arises little by little...This was the situation of Palestine, which for many centuries had been in the deepest sleep, until it was shaken by the great war, shocked by the Zionist movement, and violated by the illegal policy [of the British]; and it awoke, little by little.\n\nWith that, let's look into post-WWI Palestinism, and why/how it developed as it did."
]
}
|
[] |
[] |
[
[]
] |
|
gfxpt
|
Good introduction to gauge theory?
|
I'm a computer science person who finds all sorts of physics interesting. I've read a decent bit, but have been unable to get an understanding on just what gauge theories actually are. I don't understand what SU(1) is, what the exceptional Lie group E8 is, and I want to know.
Can anyone point me towards a reference that won't treat me like a *complete* idiot, but will still be able to explain to a non-pysicist (and non-mathematician) what's going on? I've tried the various Wikipedia articles on this subject, and they've not helped.
Thanks
|
askscience
|
http://www.reddit.com/r/askscience/comments/gfxpt/good_introduction_to_gauge_theory/
|
{
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"I'm sorry, I don't believe that you'll be able to get in to studying gauge theories without the mathematics. I don't believe it's possible.\n\nIf you do want to delve into the mathematics, though, I suggest studying the simplest case of a gauge theory, which is classical electromagnetism. There are many good books covering classical EM at the intermediate level, and of these I recommend the book by Griffiths.\n\nIt's just that, unlike discussions of very visible things like astrophysical objects or floating high voltage ionocrafts, it's very hard to convey what these abstract notions of fields and gauge symmetries are without going into the mathematics anyway. And if I were to try to avoid the mathematics, it would just sound like a complete and random load of horsepoop. :/",
"I'm a very intuitive person, and I fucking HATE group theory, so maybe I can relate to you. Here's what I can relay to you.\n\n\nSO(1) is just 1. SO(N) is the set of N by N orthogonal matrices with real entries that have determinant 1. Why is determinant 1 special? Because it preserves length. If you have a vector in 2D labeled (x, y), and multiply it by an element of SO(2) such that the result is (x', y'), the length sqrt(x^2 +y^2 ) = sqrt(x'^2 +y'^2 ). There is 1 parameter in SO(2) because there is 1 angle in 2D. There are 3 parameters in SO(3) because there are 3 angles in 3D. etc. etc.\n\n\nSU(1) is just 1. SU(N) is the set of N by N unitary matrices with complex entries with determinant 1. It also preserves \"length\", but of complex valued vectors called spinors. Why is it useful? Quantum mechanical objects are frequently spinors. This is probably the hardest and the most useful set of groups to consider...\n\nU(1) is e^(i*phi) . U(N) is the set of N by N unitary matrices that have determinant with absolute value 1. U(1) has 1 free parameter. It is the same thing mathematically as SO(2). ",
"To understand gauges you need to understand lie groups, and to understand lie groups you need group theory and some other grodier stuff. I wondered this too but it's just a really REALLY long road from zero to gauge theory. What you CAN sorta do is learn the sort of physics that's being generalized, recognize the innate symmetries and go OHHH so THAT symmetry is called U(1)... or something.\n\nNow, if you'll allow me to talk out of my ass because I'm an undergraduate and have no business talking about these things... You can start with the sorta idea that a gauge freedom is a sort of freedom in how you can get the same result. You can add a constant to your standard potential energy for instance and still get the same physics. In electrodynamics, you have a quantity called the vector potential, and it's gauge freedom manifests itself in how you can add \\del f to it for any function f, and the system won't really care. We say U(1) circle group because there are ways to get this function f to manifest itself as a rotation in phase of the wave function. Now the idea of it being sort of a manifold and a group duct taped together kinda makes sense. We have a binary operation which is defined as adding two angles together (think a clock where you start at 3 o'clock, add 2 hrs, 5 o'clock, you're just spinning around the clock). We have closure over the angles from 0 to 2\\pi since you can keep adding angles together and you'll just literally go around in a circle, the same circle, associativity, identity, inverse, yada yada. So it's a group. It's also a differentiable manifold because um... couldn't tell you why. So yeah... this U(1) gauge freedom embodies the sort of symmetry and freedom we have to choose our vector potential in this case but it also manages to hammer out our freedom to choose phase, conservation of charge due to noether's theorem, all kinds of nice things.\n\nNow, SU(2) is just 2x2 matrices with certain constraints... I don't understand this bit at all but, you might wanna start at the Pauli matrices because they're the basis we typically choose for describing the spin of particles.\n\nSU(3) is just... quarks? Hmm... I dunno\n\nE8 is just... umm... yeah okay I go now."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
6oolif
|
How much control did ancient empires actually have over their territories?
|
For example this map of the Assyrian Empire (_URL_0_). Was everyone in this territory under Assyrian administration? Could some remote village exist and be de facto independent? What about border control?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/6oolif/how_much_control_did_ancient_empires_actually/
|
{
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"Using the Romans as an example (largely because I did a ton of work in NT/Early Christianity for a few years), it varied. Certain areas of the empire were under less control than the others. Take, for example, the province of Judea, where it's often said that Roman careers came here to die. The Roman prefect/procurator (it changed in the mid-60s, I think, see Sherwin-White's *Roman Society and Roman Law in the NT*) was nominally the head of the colony. He made the decisions. In certain cases, he had the authority to have people arrested and sent to Rome, c.f. Colin Hemer's *The Book of Acts in the Setting of Hellenistic History.*\n\nHowever, the governor did not rule alone in most cases. In the case of Judea, he had a series of client kings (e.g. Herod the Great, Herod Antipas, Archelaus, etc.) who ruled their own lands for administrative ease and (often) in an attempt to be sensitive to the needs of the subjugated people. These rulers would often oversee some of the more tedious, day to day aspects of administration, leaving the governor to deal with much more significant issues. \n\nI can't commentate as to border control, but as to your remote village question, yes, absolutely. The most notable example I can think of is the Qumran community, who, while nominally under Roman rule, seem to have more or less done its own thing for the better part of the 100+ years until the Romans destroyed the site (c.f. Magness' *The Archeology of the Dead Sea Scrolls* or De Vaux's *Archeology and the Dead Sea Scrolls.* "
]
}
|
[] |
[
"http://www.lloydthomas.org/Graphics/AssyrianEmpireX.png"
] |
[
[]
] |
|
345l1j
|
If humans could process gasoline for energy, how much gas would we need per day?
|
askscience
|
http://www.reddit.com/r/askscience/comments/345l1j/if_humans_could_process_gasoline_for_energy_how/
|
{
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"text": [
"[The energy in 1 gallon of gasoline is 31,500 food calories,](_URL_0_) so for a typical 2,500 calories a day, that's 0.079 gallons, or 251g. This much butter would only give 1,800 calories. \n\nOr 1 gallon of petrol provides 12.6 days worth of food!",
"The average human male requires about 2500 food calories a day, while the average woman is around 2000. Food calories are actually kilocalories, so this works out to 2.5x10^6 calories a day for a man and 2x10^6 for a woman. Gasoline, according to [wikipedia](_URL_0_) has an energy density of 32.4 MJ/L. There are 239 000 calories for every MJ, so our daily human energy intake in kcal becomes 10.46MJ for a man and 8.37MJ for a woman.\n\nUsing our energy density of 32.4MJ/L for gasoline we find that the average man would need to consume 0.32L of gasoline a day, and the average woman would need 0.26L. This assumes that these people are as efficient in metabolizing gasoline as we are at metabolizing food.",
"I'll take a shot at some conversions here. Please bear with me, my math may be slightly off (rounded).\n\nassuming one requires 2000C per day in food energy, 239.01kcal = 1MJ (megajoule), and gasoline has an energy density of 44.4MJ/kg, we can determine that it would 188.5g of gasoline to power the average human for a day.",
"Actually, vegetable oil has roughly the same calories per unit as gasoline. 1 cup is ~2000 kcal, which is about what you need per day. While efficient from a calorie perspective, it probably wouldn't meet all of your nutritional needs."
]
}
|
[] |
[] |
[
[
"http://home.dejazzd.com/kgard/bcn/calories_in_gallon.html"
],
[
"https://en.wikipedia.org/wiki/Energy_density"
],
[],
[]
] |
||
5hkoob
|
if energy can't be created or destroyed how can the universe expand at an exponential rate, seeing as the same amount of energy has theoretically existed since the big bang?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5hkoob/eli5_if_energy_cant_be_created_or_destroyed_how/
|
{
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"In physics laws of conservation (like the conservation of energy) rely on a fundamental symmetry, which means that if you can transform a property of your physical system while not changing how the system itself works (in smartass terms it's invariant under a transformation), then there's a conserved quantity tied to this invariance. This principle is called [Noether's Theorem](_URL_0_)\n\nThe conservation of energy can be derived from a time invariance of a system. Meaning you can start a process (like dropping a ball) whenever you want and get the same result every time (it drops to the ground), and here's where to problem comes into play.\n\nAn expanding Universe is clearly __not__ time invariant, since you can easily distinguish an earlier state from a later state by the fact that galaxies are further apart. And hence the conservation of energy does not apply to an expanding universe (at least not globally).",
"The expansion of space-time isn't linked to any clear understanding we have of energy because space-time isn't a mass-energy entity in and of itself. Theories and some experiments indicate it contains rapidly created and destroyed pairs of particles and anti-particles for a net-zero energy.\n\nRight now the energy associated to space-time expansion is being called \"dark energy\" the same way \"dark matter\" indicates mass we can detect by influence on other masses but not detect by any additional means (like seeing the object)"
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Noether%27s_theorem"
],
[]
] |
||
1myxcf
|
Where Do the Ancestors of the Modern Germans Now Living in Germany Originate From?
|
In the early history of the Roman empire we're taught that the Germans caused lots of trouble for the Romans. The Cherusci, the Chatti, the Bructeri, etc. I'm assuming these tribes were eventually assimilated into other Germanic tribes, and then by those migrating West. What do we know of the people currently living there? Were their ancestors originally from the Balkans and that region, or are they the descendants of those ancient tribes that struggled with the Romans?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1myxcf/where_do_the_ancestors_of_the_modern_germans_now/
|
{
"a_id": [
"ccen0eo"
],
"score": [
2
],
"text": [
"A large part of the Germans today are actually the descendants of the Tribes that used to live there. Its true that many migrated west, but the larger proportion stayed in germany."
]
}
|
[] |
[] |
[
[]
] |
|
1z8bxq
|
Would the whole earth be affected by an EMP from a coronal mass ejection, or would the side facing the sun only be affected?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1z8bxq/would_the_whole_earth_be_affected_by_an_emp_from/
|
{
"a_id": [
"cfro4r3"
],
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"text": [
"A CME (Coronal Mass Ejection) does not produce an EMP (ElectroMagnetic Pulse). It's simply an ejection of charged particles from the sun, aka solar wind.\n\nThe solar wind compresses Earth's magnetosphere on the day side and \"pulls\" on the night side.\n\nWhen Earth is hit by a large CME shock wave the magnetosphere \"wobbles\", meaning Earth's magnetic field is disturbed and fluctuates. The greater the disturbance, the greater the variation. This is known as a geomagnetic storm.\n\nThe varying magnetic field induces currents on metals, causing disturbances and even damages to the power grids (which can be seen as large metal nets) across the globe.\n\nIn 1859 Earth experienced the [Carrington Event](_URL_0_), a massive solar storm which would be a disaster in modern age. In 1989 [Quebec's power grid went down](_URL_2_) as an effect from a solar storm, this storm also [destroyed a transformer in a nuclear power plant in New Jersey](_URL_1_).\n\nTL;DR: The entire Earth is affected from a CME."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Solar_storm_of_1859",
"http://www.scientificamerican.com/article/geomagnetic-storm-march-13-1989-extreme-space-weather/",
"http://en.wikipedia.org/wiki/March_1989_geomagnetic_storm"
]
] |
||
3y8fce
|
What exactly is going on in your eyes and brain when you see something that's "too bright?"
|
askscience
|
https://www.reddit.com/r/askscience/comments/3y8fce/what_exactly_is_going_on_in_your_eyes_and_brain/
|
{
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"Rhodopsin is a protein that changes conformation in response to light, as a g-coupled receptor this passes the signal on to nerve fibres, which then passes it into the brain, and then in time resets itself. \n\nHowever, this therefore means it is a saturateable system, once all your Rhodopsin proteins change conformation to the \"on\" setting, you essentially can't visualise anything until they reset, normally this would happen periodically so you can see like you normally do, while the iris would \"protect\" these cells and the proteins within them only allowing a useful amount of light to access the cells, however in the event of bright light, a time when the iris either didn't close fast enough, or is already at full relaxation, too much light gets through saturating the Rhodopsin proteins meaning you only see that point in time until they once again reset. \n\nSo what happens to the eye is rhodpsin in saturated, constantly sending a fully \"on\" signal to the brain, which the brain reads as brightness, normally this happens at a lower level so the brain can process the information and tell everything you see in front of you. For trivas sake, this is also why red light doesn't lead to loss of night vision, saturation with red light doesn't activate your rod cells, only the red cone cells, and therefore essentially the nightvision part of your eye can't see it, whereas of course saturation with \"bright light\" actually means saturation with white light, a mixture of all visible wave lengths and therefore saturation of all colours of rods and cones."
]
}
|
[] |
[] |
[
[]
] |
||
nfih0
|
What is instinct? How does it guide an animal's behavior?
|
I was thinking about animals and their natural-born instincts. As I understand animals, they are born with a drive towards certain behavior, and we call this "instinct." For example, they know what their diet should be.
I'd assume that if a baby lion that had never had contact with other lions were given a choice, it would know to choose to eat meat over vegetables. Is that true? If so, how is that information "programmed" into an animal without outside forces guiding the animal? If it wouldn't know instinctually, would it eat the vegetable, get sick and learn that way?
|
askscience
|
http://www.reddit.com/r/askscience/comments/nfih0/what_is_instinct_how_does_it_guide_an_animals/
|
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"I would respectfully disagree with the current top response. Our current understanding of animal behavior is such that each observed action is guided by a variety of factors and can have varying amounts of influence from genetics or ontogeny (learning). The nature vs. nurture argument is effectively null as no behavior is ever entirely controlled by genotype and neither does there exist one free of its influence.\n\nMy favorite example is birdsong. Our current understanding is that there is a genetic template that predisposes a bird to its species' song. However, there is a \"sensitive period\" during which it must cement and learn its song, the process of which is called crystallization, or else the result can be gibberish compared to song from birds allowed to develop normally. In fact, the learning and development of birdsong, which seems to have a solid genetic template, is theorized to even continue beyond crystallization and [possibly rely on feedback from one's own song](_URL_0_) or others just to maintain its integrity. On the complete end of the scale, birds with less complicated calls that we don't consider true birdsong [don't seem to need the learning component at all](_URL_1_), though this is still reliant on the development of the necessary brain structures for vocalization. [This paper](_URL_6_) gives a good review on birdsong. It is extremely like human language, which you may want to look up papers on as well if you want to see a good example of a human behavior that draws plentifully from \"innate\" vs. learned components.\n\nResdriden's citing of genetic influence on taste is entirely accurate - a well-known example in humans is the ability to taste a toxin in plants known as PTC, a reference to which can be found in [this paper](_URL_3_)'s introduction. Additionally, felines (as a rare exception in Mammalia) [do not taste sweetness](_URL_5_). The genetic influence of taste, then, for your example could easily help predispose lions to meat. But what about the effects of social enrichment on hunting, which are important for any animal with a CNS - even [rats](_URL_2_) and [spiders](_URL_4_)? We assume a lion know to eat meat if it never observed any other animal doing so, but to what degree can they really know their own diet and know what food to forage for? These are excellent questions to ask with complicated answers, and little if any behavior is truly \"hardwired\" in besides perhaps reflexes, which in another can of worms may themselves be learned - think of people you know who will vomit even today if they try to eat foods that coincided with them getting sick as children. ",
"I would respectfully disagree with the current top response. Our current understanding of animal behavior is such that each observed action is guided by a variety of factors and can have varying amounts of influence from genetics or ontogeny (learning). The nature vs. nurture argument is effectively null as no behavior is ever entirely controlled by genotype and neither does there exist one free of its influence.\n\nMy favorite example is birdsong. Our current understanding is that there is a genetic template that predisposes a bird to its species' song. However, there is a \"sensitive period\" during which it must cement and learn its song, the process of which is called crystallization, or else the result can be gibberish compared to song from birds allowed to develop normally. In fact, the learning and development of birdsong, which seems to have a solid genetic template, is theorized to even continue beyond crystallization and [possibly rely on feedback from one's own song](_URL_0_) or others just to maintain its integrity. On the complete end of the scale, birds with less complicated calls that we don't consider true birdsong [don't seem to need the learning component at all](_URL_1_), though this is still reliant on the development of the necessary brain structures for vocalization. [This paper](_URL_6_) gives a good review on birdsong. It is extremely like human language, which you may want to look up papers on as well if you want to see a good example of a human behavior that draws plentifully from \"innate\" vs. learned components.\n\nResdriden's citing of genetic influence on taste is entirely accurate - a well-known example in humans is the ability to taste a toxin in plants known as PTC, a reference to which can be found in [this paper](_URL_3_)'s introduction. Additionally, felines (as a rare exception in Mammalia) [do not taste sweetness](_URL_5_). The genetic influence of taste, then, for your example could easily help predispose lions to meat. But what about the effects of social enrichment on hunting, which are important for any animal with a CNS - even [rats](_URL_2_) and [spiders](_URL_4_)? We assume a lion know to eat meat if it never observed any other animal doing so, but to what degree can they really know their own diet and know what food to forage for? These are excellent questions to ask with complicated answers, and little if any behavior is truly \"hardwired\" in besides perhaps reflexes, which in another can of worms may themselves be learned - think of people you know who will vomit even today if they try to eat foods that coincided with them getting sick as children. "
]
}
|
[] |
[] |
[
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"http://www.sciencedirect.com/science/article/pii/016310479290757U",
"http://www.sciencedirect.com/science/article/pii/S0003347205800478",
"http://www.sciencedirect.com/science/article/pii/S0166432897001423",
"http://www.bmj.com/highwire/filestream/197790/field_highwire_article_pdf/0.pdf",
"http://www.springerlink.com/content/4xq4wqlfjtjbf0yt/",
"http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.0010003",
"http://courses.washington.edu/ccab/Brenowitz%20et%20al%20on%20bird%20song%20system%20-%20JNB%201997.pdf"
],
[
"http://www.sciencedirect.com/science/article/pii/016310479290757U",
"http://www.sciencedirect.com/science/article/pii/S0003347205800478",
"http://www.sciencedirect.com/science/article/pii/S0166432897001423",
"http://www.bmj.com/highwire/filestream/197790/field_highwire_article_pdf/0.pdf",
"http://www.springerlink.com/content/4xq4wqlfjtjbf0yt/",
"http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.0010003",
"http://courses.washington.edu/ccab/Brenowitz%20et%20al%20on%20bird%20song%20system%20-%20JNB%201997.pdf"
]
] |
|
cjentp
|
In an era of rapid urbanization and technological advancement, why did the Nazis feel that lebensraum - that is, lots of agricultural land - was necessary?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/cjentp/in_an_era_of_rapid_urbanization_and_technological/
|
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"Lebensraum had a lot of its roots in the problems Germany encountered in WW1.\n\n & #x200B;\n\nDuring the First World War, the Central Powers ran into major supply issues in many areas, arguably the most critical being food. Germany and Austria Hungary were dependent on food imports prior to WW1, and the British naval blockade was incredibly effective at cutting off the food supplies of the Central Powers. Further exacerbating the problem was the Russian invasion of Galicia in 1914, which was a prime food-producing region for Austria Hungary. The Central Powers suffered from major food shortages through the entirety of the war, and the situation by the end of the war had deteriorated in Austria that even metropolitan areas like Vienna were suffering from near-starvation level rations. The core of the issue was that neither Germany nor Austria Hungary were self-sufficient when it came to food, and thus they were incredibly vulnerable to blockade or even embargo.\n\n & #x200B;\n\nAs the war went on, Germany resorted to a lot of measures that serve as stepping stones for a lot of the ideals of Lebensraum. Chief among these is Ober Ost. Ober Ost was an occupation administration that ran German-occupied areas in the Baltic practically as colonies. They resorted to forced labor and requisitioned food, and the scale and severity of these tactics would increase as the war worsened for Germany. By the end of the war, the locals in Ober Ost were being kept on starvation rations and as much food as possible was being requisitioned for Germany proper, but to no avail - the German administration there never managed to make much of a \"profit\" when it came to the resources they hoped to gain from the region. Similar tactics would also be used in other German-occupied areas such as Belgium, although not to the scale or severity of Ober Ost. These problems also played a part in the creation of the occupied zone after the Treaty of Brest-Litovsk - the Central Powers were to occupy the majority of Ukraine, the hope being that the fertile region would be able to finally put an end to the food shortages at home.\n\n & #x200B;\n\nUltimately, despite Germany's fairly brutal efforts to break its dependency on foreign food imports during WW1, the regions they occupied always ended up being a drain on the German war effort rather than a net gain, especially when it came to food. Lebensraum as it took shape (and a lot of the more banal Nazi atrocities in the East) would largely serve as an extension of their practices in WW1 with the intention of finally making Germany resilient against a blockade or embargo. To that extent, they hoped for not only capture of large areas of food-producing land, but major reorganizations and colonizations of these regions in order to better orient them for meeting German wartime and long-term needs. Given that experience in WW1 showed that the existing populations in the East ultimately ended up being a drain on resources even when limited to the absolute bare minimum rations, the logical extension here was particularly brutal - forced labor from enough of the population to support colonization, and deportation or extermination of the remainder of the population. Fortunately, German efforts in WW2 did little better than WW1 despite being significantly more destructive. Germany suffered the same kinds of food shortages they experienced in WW1, and Germany was never able to establish the kind of agricultural base it hoped for in the East."
]
}
|
[] |
[] |
[
[]
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||
huo0l
|
Is there any difference between the singularity that existed just before the Big Bang and those which occur in Black Holes?
|
I'm having this doubt since, at least by my current understanding, the primordial singularity spontaneously gave way to the Big Bang; if the two singularities are not different, would a singularity of sufficient mass actually possibly create such a second 'Big Bang'? My understanding seems to hit a roadblock since in the former case, time as such didn't exist; whereas in the latter, the formation of the singularity does happen along distinct points in time. If they are different, then in what way are they different? I am not a Physics major but I still can follow a technical explanation.
For context, I was reading this [lecture by Dr. Stephen Hawking](_URL_0_)where I came across this line: "[The singularity theorems, proved by Hawking and Penrose] showed that if General Relativity were correct, the universe would have begun with a singularity." That was the genesis of this line of thought.
|
askscience
|
http://www.reddit.com/r/askscience/comments/huo0l/is_there_any_difference_between_the_singularity/
|
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"There was no singularity. \n\nFrom [Victor J. Stenger](_URL_0_):\n\n > This claim is based on a theorem derived from Einstein's general relativity and published by Stephen Hawking and Roger Penrose in 1970, which concluded that the universe began with a singularity. Over 20 years ago now, Hawking and Penrose admitted that there was no singularity because their calculation, while not wrong as far as it went, had not taken into account quantum mechanics. (See page 50 of Hawking's 1988 bestseller A Brief History of Time.) I do not know of a single working cosmologist today who says the universe began with a singularity.\n\nAlso, here is a [PDF](_URL_1_) of his on the same topic.\n\nEdit:\n\nFrom A Brief History of Time:\n\n > In 1965 I read about Penrose’s theorem that any body undergoing gravitational collapse must eventually form a\nsingularity. I soon realized that if one reversed the direction of time in Penrose’s theorem, so that the collapse\nbecame an expansion, the conditions of his theorem would still hold, provided the universe were roughly like a\nFriedmann model on large scales at the present time. Penrose’s theorem had shown that any collapsing star\nmust end in a singularity; the time-reversed argument showed that any Friedmann-like expanding universe\nmust have begun with a singularity. For technical reasons, Penrose’s theorem required that the universe be\ninfinite in space. So I could in fact, use it to prove that there should be a singularity only if the universe was\nexpanding fast enough to avoid collapsing again (since only those Friedmann models were infinite in space).\n\n > During the next few years I developed new mathematical techniques to remove this and other technical\nconditions from the theorems that proved that singularities must occur. The final result was a joint paper by\nPenrose and myself in 1970, which at last proved that there must have been a big bang singularity provided\nonly that general relativity is correct and the universe contains as much matter as we observe. There was a lot\nof opposition to our work, partly from the Russians because of their Marxist belief in scientific determinism, and\npartly from people who felt that the whole idea of singularities was repugnant and spoiled the beauty of\nEinstein’s theory. However, one cannot really argue with a mathematical theorem. So in the end our work became generally accepted and nowadays nearly everyone assumes that the universe started with a big bang\nsingularity. It is perhaps ironic that, having changed my mind, I am now trying to convince other physicists that\nthere was in fact no singularity at the beginning of the universe – as we shall see later, it can disappear once\nquantum effects are taken into account.",
"The big bang singularity extends across all space for one point of time. The black holes singularity extends across all time at one point. So yes, they are different.\n\nEdit: Another way they are different is in the scalings of curvature invariants near the singularity. For the black hole singularity, the Kretchmann scalar blows up as r^-6 as r- > 0. For the FRW singularity, the Kretchmann scalar blows up as (c^2 a^2 + b^4 ) / a^4 (where b = da/dt, c = db/dt) as a- > 0."
]
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|
[] |
[
"http://www.hawking.org.uk/index.php/lectures/physicscolloquiums/68"
] |
[
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"http://www.huffingtonpost.com/victor-stenger/did-the-universe-come-fro_b_739909.html",
"http://www.colorado.edu/philosophy/vstenger/Briefs/Singular.pdf"
],
[]
] |
|
4qpouf
|
In what format do nerves relay information to the brain? i.e., how does the brain “read” the information it receives from the nervous system?
|
askscience
|
https://www.reddit.com/r/askscience/comments/4qpouf/in_what_format_do_nerves_relay_information_to_the/
|
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"All neurons transmit electro-chemical pulses. Every pulse is the same. Information about the strength of the signal is encoded in the frequency of the pulses. The signals for different sensations are carried on different neurons.",
"You're begging the question here: DOES the brain \"read\" the information it receives from the nervous system? Many philosophers of mind argue that representations cannot be the basis of thought since they would lead to an infinite regress. If each stage of mental processing produces a \"representation\" to be \"read\" by the next stage, then where is the final \"reader\" and how does it function? It might be more useful to think of the mind (or the brain) as responding to information rather than \"reading\" it.\n\nThis might seem pedantic but it's illuminating in looking at how the brain actually does work. There is no one, unifying code that scientists have discovered that makes sense of all forms of neural processing, and even within particular systems (like the visual system, or the auditory system) there may be a multiplicity of codes and structures. \n\nFor example in the visual system some functions are organised *spatiotopically* (in relation to where signals come from in outside space) and some are organised *retinotopically* (relative to the positions of source cells on the retina). Spatiotopic organisation also occurs in the auditory system, but the equivalent of retinotopy for audition would be pitch sensitivity, since the sound-sensitive hair cells on the cochlea are organised in order of pitch (_URL_1_). You may also have made the leap of noticing that all information in the visual system is *initially* retinotopic because the information comes from cells on the retina. In order to make that information spatiotopic the brain has to integrate not just the raw visual data but also information about where the eyes are pointing. Thus even a sense seemingly as simple as vision is actually a multimodal process requiring multiple different \"codes\" to be \"deciphered\".\n\nThen there is the question of consciousness. We aren't conscious of the vast majority of the information our senses provide. So if you want to know how our consciousness reads the information it receives the answer is it discards most of it.\n\nAt the most basic level we know a lot about how information is *transmitted* from place to place in the brain. Sensory neurons transduce energy in the outside world (in the form of light, pressure, heat etc) into action potentials (waves of electrical potential difference that roll along the length of the neuron). Action potentials (sometimes colloquially referred to as \"spikes\") cause the release of neurotransmitters at the end of the neuron. Neurotransmitters chemically trigger or dampen surrounding neurons. In many sensory domains scientists have been able to understand the relationships between sensory stimuli and the patterns of spikes they produce (e.g. _URL_0_).\n\nThere are broader general debates about the principles of neural encoding (e.g. _URL_2_) but as far as I understand it these remain mostly theoretical, and the language in your opening question remains philosophically contentious.",
"Sensory information usually originates in receptor cells (like the rods and cones in your retina), which often are not neurons but are capable of communicating with neurons. \n\nTypically, receptor cells synapse with nerve cells, and either those nerve cells connect to the brain (via very long axons) or those nerve cells connect to another local nerve cell, which maybe connected to another local nerve cell, which connects to another nerve cell that has a very long axon and connects to the brain.\n\nThe axons of neurons connecting to the brain are usually bundled into nerves. A 'nerve' is a bundle of many axons. Where a sensory nerve (i.e. a nerve made up of the axons of neurons carrying sensory info) reaches the brain, the individual axons in the nerve will usually go a short distance further within the brain and then synapse with another neuron.\n\nThe first, and most obvious element of how the brain interprets neural signals coming from the periphery (periphery meaning everything outside your central nervous system) is that different neurons carry different information. Projections from the retina (projections = connections going from neurons in one area to neurons in another area) go to visual areas in the brain. If some neurons in your retina accidentally projected to your primary auditory cortex, you might hear sounds in response to bright lights. If neurons from your ear accidentally got connected to your primary visual cortex, you might see dots of light in response to sounds.\n\nNow, how does the visual cortex or auditory cortex know what the signals mean?\n\n1: Labeled line coding\n\nLabeled line coding is when something is encoded by *which neuron(s) fire*. In the auditory system, for most frequencies of sound, different neurons respond to different frequencies. So if you hear a 440 Hz tone, one neuron responds, but if you hear a 450 Hz tone, a different neuron responds. The brain can interpret what frequency a sound was by looking at which neuron fires. Labeled line coding is usually used to identify different stimuli, but that doesn't mean that labeled line coding is ALWAYS used. \n\n2: Across fiber pattern coding\n\nSlightly more complicated version of labeled line coding. In AFP coding, a specific stimulus is identified by a *combination* of neurons firing. This is common in the olfactory (smell) system. Say, neurons A and B fire in response to banana smell, but A and C fire for strawberry, etc.\n\n3: Rate coding\n\nRate coding refers to something being encoded by changes in a neuron's firing rate. In the auditory system, for most frequencies, labeled line coding is used to encode *what frequency(s)* a sound is, and rate coding is used to encode *how intense* it is. The louder the sound, the more the neuron's firing rate increases. Rate coding is often used to encode intensity, but not always.\n\n4: Temporal codes\n\nSometimes, a neuron can \"respond\" (in the sense of increasing / decreasing its firing rate) equally to more than one stimulus. In many cases, this is probably because the neuron isn't actually encoding what the stimulus is. Say we're talking about taste: If I find a neuron that responds equally to bitter and sour tastes (both of which are generally unpleasant by themselves), that neuron might not be carrying information about taste at all. It might just be that neuron's job to fire when something tastes nasty.\n\nBUT, some neurons can send different messages using different patterns of spikes, kind of like Morse code.\n\nThen, there are probably lots of other ways neurons encode information. Some neurons in the hippocampus change their *phase angle relative to a background rhythm* depending on whether a rat is moving towards a particular location, or away from it. That's analogous to if you said to your roommate: \"OK, I'm bringing a date home tonight, and we're going to be watching Netflix and chilling in the living room and I don't want you interrupting us if we're making out. So once every fifteen minutes or so I'm going to kick the couch. If you hear me kick the couch right before the second hand passes 60, that means it's all clear and you can come into the living room if you want. But if you hear me kick the couch when the clock's second hand is around the 3 o'clock mark, then stay out.\"\n\nThis assumes that you have multiple well-synchronized analog wall clocks in the house."
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"http://www.jneurosci.org/content/23/27/9146.full.pdf",
"https://mechanicalcochlea.files.wordpress.com/2011/04/hz-of-cochlea.png",
"http://www.cell.com/trends/neurosciences/abstract/S0166-2236(15)00119-8?_returnURL=http%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0166223615001198%3Fshowall%3Dtrue&cc=y="
],
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||
l8lgi
|
how a turbo works in a car.
|
Thanks for the responses.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/l8lgi/eli5_how_a_turbo_works_in_a_car/
|
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"Assuming you know basically how a normal (naturally aspirated) engine works...\n\nA turbo basically has two halves. The two halves share a shaft that is connected to more or less a fancy fan on each side. So this shaft spins freely and is connected to both sides -- if you spin the fan on one side of the turbo, the other fan on the opposite side will also spin.\n\nSo, you connect the the exhaust portion of your turbo to the exhaust of your engine. As your motor revs up and puts more and more exhaust gasses out, the gasses enter the turbo, spin the fan, and exit to the rest of your exhaust system (and out the car). So by spinning the fan on the exhaust side, it also spins the fan on the intake side. So on the intake side this basically creates a vacuum pulling in the air from outside, and forces that air into the intake manifold of your engine. \n\nWhen you have more air going in, you can have more fuel going in -- which translates to more power output from the motor.",
"Turbo is no more than 2 fans connected by an axle.\n\nAs the exhaust gas hits the exhaust fan/impeller, it turns. Very quickly (40,000 rpm).\n\nNow, because the exhaust fan is connected to the intake fan, the latter spins, thus creating pressure. Also called, boost.\n\nHigher pressure means more air particles. Add fuel in the proper ratio, and you're stuffing more combustible in the engine, which means you're getting more torque and power.\n\nIf this were ELI6, I would also point out that turbos generate a lot of heat, and adding intercoolers (between the intake fan and actual intake) helps keep the temperature down, increasing the air density and generally making the engine run better.\n\nAnd ELI7, we'd debate over turbo size, flow, lag and whatnot.",
"To make a car faster, you need to fit as much air as you can into the engine.\n\nA turbo uses the exhaust gas coming out of the engine to spin a little wheel that pushes a lot of air into your engine, much more air than the engine could get by itself.\n\nMore air = more fuel can be burned = more power.",
"Whats the difference between this and a supercharge? ",
"It sounds like something for nothing, like a perpetual motion machine. I found it hard to believe they actually worked, but the magic is in the wasted energy in the exhaust that, when harvested, does not really impede the engine much, and the multiplier effect of that extra oxygen, you get a lot more combustion for not that much compressive force.\n\nStill might be magic.",
"Everyone here is right. If you were wondering about the PSHHHH! when you let of the gas, that's called a blow-off valve. Pressurized air from the turbo is forced through throttle body (and thus, the intake manifold) when you're on the gas pedal, but when you release the pedal the little plate on the throttle body closes and causes pressure to build up inside the pipe. That's when a pressure sensitive valve opens up and releases all that built up air into the engine bay.",
"A turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.",
"Just to clarify: forcing all that extra air into the engine requires more fuel - petrol, whatever - to stop the mix burning too lean. It's not *free* extra power, by any means. ",
"The fart from ur car spins a fan which give more air for your car to breathe and make more power to fart harder. :D",
"I drive a DSM from my understanding they don't work",
"Assuming you know basically how a normal (naturally aspirated) engine works...\n\nA turbo basically has two halves. The two halves share a shaft that is connected to more or less a fancy fan on each side. So this shaft spins freely and is connected to both sides -- if you spin the fan on one side of the turbo, the other fan on the opposite side will also spin.\n\nSo, you connect the the exhaust portion of your turbo to the exhaust of your engine. As your motor revs up and puts more and more exhaust gasses out, the gasses enter the turbo, spin the fan, and exit to the rest of your exhaust system (and out the car). So by spinning the fan on the exhaust side, it also spins the fan on the intake side. So on the intake side this basically creates a vacuum pulling in the air from outside, and forces that air into the intake manifold of your engine. \n\nWhen you have more air going in, you can have more fuel going in -- which translates to more power output from the motor.",
"Turbo is no more than 2 fans connected by an axle.\n\nAs the exhaust gas hits the exhaust fan/impeller, it turns. Very quickly (40,000 rpm).\n\nNow, because the exhaust fan is connected to the intake fan, the latter spins, thus creating pressure. Also called, boost.\n\nHigher pressure means more air particles. Add fuel in the proper ratio, and you're stuffing more combustible in the engine, which means you're getting more torque and power.\n\nIf this were ELI6, I would also point out that turbos generate a lot of heat, and adding intercoolers (between the intake fan and actual intake) helps keep the temperature down, increasing the air density and generally making the engine run better.\n\nAnd ELI7, we'd debate over turbo size, flow, lag and whatnot.",
"To make a car faster, you need to fit as much air as you can into the engine.\n\nA turbo uses the exhaust gas coming out of the engine to spin a little wheel that pushes a lot of air into your engine, much more air than the engine could get by itself.\n\nMore air = more fuel can be burned = more power.",
"Whats the difference between this and a supercharge? ",
"It sounds like something for nothing, like a perpetual motion machine. I found it hard to believe they actually worked, but the magic is in the wasted energy in the exhaust that, when harvested, does not really impede the engine much, and the multiplier effect of that extra oxygen, you get a lot more combustion for not that much compressive force.\n\nStill might be magic.",
"Everyone here is right. If you were wondering about the PSHHHH! when you let of the gas, that's called a blow-off valve. Pressurized air from the turbo is forced through throttle body (and thus, the intake manifold) when you're on the gas pedal, but when you release the pedal the little plate on the throttle body closes and causes pressure to build up inside the pipe. That's when a pressure sensitive valve opens up and releases all that built up air into the engine bay.",
"A turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.",
"Just to clarify: forcing all that extra air into the engine requires more fuel - petrol, whatever - to stop the mix burning too lean. It's not *free* extra power, by any means. ",
"The fart from ur car spins a fan which give more air for your car to breathe and make more power to fart harder. :D",
"I drive a DSM from my understanding they don't work"
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
|
3de33r
|
In the later stages of WWII, the Soviets emptied their prisons to fill their ranks. How did all these trained and battle-hardened convicts affect post-war Russia?
|
Listening to Dan Carlin's *Hard Core History* and reading a few other sources on the Eastern Front I learned that in the later stages of WWII the Soviet Government was scraping the bottom of the barrel of able soldiers and emptied more than few prisons to boost their manpower. Once the war was over how did they deal with these convict-soldiers who had been given training and many of whom now had combat experience and possibly a taste for blood after the sacking of East Germany. Did they cause significant trouble for post-war Russia? Did they receive pardons in exchange for service?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/3de33r/in_the_later_stages_of_wwii_the_soviets_emptied/
|
{
"a_id": [
"ct4uatl"
],
"score": [
5
],
"text": [
"Do you mean penal battalions (shtrafbats/shtrafniki)?\n\nIf so, I refer you to a previous comment/post in a similar vein:\n\n_URL_0_\n\nThe comment seems to imply that the prisoner units were used in essentially suicide missions (\"human mine clearers\"), and had horrifying mortality rates. So the result would most likely be a lot of dead prisoners, with very few military-trained criminals who actually survived the war."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/2am4oz/did_the_red_army_really_use_humanwave_tactics_in/ciwj95k"
]
] |
|
vdjvd
|
What causes those small holes at the beach in the sand that releases air when the water reaches them?
|
I've always been intrigued by this, these holes only exist near the water, if you take a look, you will notice that they are everywhere. When a wave comes and goes, the hole will release small bubbles of air. These holes are a few millimetres in diameter. What causes this?
|
askscience
|
http://www.reddit.com/r/askscience/comments/vdjvd/what_causes_those_small_holes_at_the_beach_in_the/
|
{
"a_id": [
"c53jelg",
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"c53kgkv",
"c53ogwk"
],
"score": [
7,
15,
3,
2
],
"text": [
"If they're the kind of hole I think you're talking about, they're caused by small crabs that burrow into the sand. They come out onto the surface to sift through the surface sand looking for nutrients so you might also see tiny ( < 1mm diameter) sand balls scattered around the holes.\n\nThe bubbles that come out when shallow waves cover them are just the air that's in the hole flowing out. It's the same principle as when you put an empty water bottle under water and bubbles of air glug to the surface.",
"well, when waves come in and out, they aren't just on the surface, the water is being pushed through the sand. This causes a displacement of air, and, Earth being as lazy as it is, the air needs to find the easiest way to escape. That's through the surface. When the wave recedes, it causes a slight suction which will pull air through the surface into the sand itself. ",
"i think you might be talking about these guys.\n\n_URL_0_",
"[Did they look anything like these razor clam holes?](_URL_0_)"
]
}
|
[] |
[] |
[
[],
[],
[
"http://www.youtube.com/watch?v=XDEHn4fBPhA"
],
[
"http://www.youtube.com/watch?v=EBxERHMUwrA&feature=related#t=95s"
]
] |
|
2b66ua
|
Black holes affect light; thus light is pulled by gravity. Does light exert its own pull in return?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2b66ua/black_holes_affect_light_thus_light_is_pulled_by/
|
{
"a_id": [
"cj27pwv",
"cj2803y"
],
"score": [
7,
17
],
"text": [
"If the light is moving at an angle relative to the black hole, yes, although it's minimal. If it's going straight towards the black hole, there isn't time for the gravitational field to reach the black hole before the photon does. However, after the collision, momentum is still conserved, so the black hole gains some momentum in the direction the photon was going.",
"Yep, light definitely does gravitate - everything does! In Einstein's gravity it's not just mass that gravitates, but mass and *energy* - and everything has energy.\n\nWhen it comes to a black hole, the gravity of the light it pulls in is pretty much always negligible by comparison. But there are instances where the gravitational pull of light is significant. The most important of these is the *radiation-dominated era* of the early Universe, for about the first 80,000 years after the Big Bang, when light was actually denser than normal matter and so was the dominant gravitational influence in the entire Universe. As a result, the Universe expanded at a different rate than later on, when matter was dominant."
]
}
|
[] |
[] |
[
[],
[]
] |
||
3hh837
|
How did Marbury v. Madison establish judicial review in the United States? What was the role of SCOTUS before this decision?
|
My understanding is that in the decision for *Marbury v. Madison*, the Supreme Court asserted its authority in determining if laws were or were not Constitutional, and this decision is the basis for how SCOTUS operates as we know it. But if SCOTUS had to assert this authority in a case, that authority must not have been explicitly granted in the Constitution - it feels like SCOTUS "bootstrapped" its power to check and balance the executive and legislative branches. How did the other branches of government react to SCOTUS "giving itself" power not expressly enumerated in the Constitution?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/3hh837/how_did_marbury_v_madison_establish_judicial/
|
{
"a_id": [
"cu7hl5j",
"cu7llo3"
],
"score": [
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4
],
"text": [
"Before the *Marbury v. Madison* case, the Supreme Court had not made any decisions that would significantly affect United States law, and was hardly recognized as an equal power to the other two branches. It had been realized that the courts had this power, but it was not until the SC had to step into the *Marbury v. Madison* that people had seen the power that they possesed.\n\n_URL_0_",
"Marbury tends to get simplified a bit when discussing the nuanced effects of what exactly happened in that case.\n\nAs background, pretty much everyone agreed that the judiciary had the job of resolving disputes by interpreting the law. And sometimes the law has more than one source.\n\nSo there's a rule out there, that came up in the common law, that verbal contracts are binding contracts. But the English parliament passed a statute called the Statute of Frauds, modifying that rule saying that contracts for transfers of interests in land, marriage contracts, any contract with more than a year's duration, and a few other types of contracts had to be in writing. So courts dealing with these issues had a parliamentary rule grafted onto their existing common law rules.\n\nAnd as you can imagine, Parliament (or its closest American successor, the U.S. Congress) can pass new statutes repealing or modifying previous laws. So courts would sometimes have to interpret inconsistent statutes to resolve a conflict.\n\nMarbury's main innovation is to say that it would not defer to Congress (who wrote the statute) or to the President (who signed the bill) in determining whether a statute passed by Congress was consistent with the meaning of the Constitution, and in clarifying that the Constitution trumps any statute passed by Congress. \n\nBut think for a second whether an opposite result would even be possible. Let's say Congress passes an ex post facto law in 2016 saying that anyone who mined bitcoins in 2015 retroactively committed a crime. Then what happens? The executive branch's prosecutors can bring criminal cases against 2015's bitcoin miners, but the court that imposes a sentence must agree that the criminal law is valid in order for that law to have any effect. It's not \"bootstrapping\" for the courts to say \"we're not going along with the other two branches' interpretation of the Constitution.\" So in a way, the independence of the judiciary (through constitutional design) makes judicial review inevitable. Laws that don't need to be interpreted by the courts can't be struck down by the courts, either (due to the way we've set up the requirement that federal courts only hear live cases or controversies). Laws that purely govern Congress or the executive branch tend not to make it into court cases, and the political question doctrine prevents the courts from interpreting many of the ones that do come up.\n\nSo Marbury isn't truly a bootstrapping problem. It's that the courts have told the public and the other two branches that it would not exercise its judicial power in a way that it doesn't independently believe to be constitutional.\n\nEdit: it's hard to condense this into sources from my phone, but a great starting point is Akhil Amar's [*Marbury, Section 13, and the Original Jurisdiction of the Supreme Court*](_URL_0_). It's mainly about another issue, but its background section makes the argument that people overstate things when they say that Marbury gave the Supreme Court the power to declare laws unconstitutional."
]
}
|
[] |
[] |
[
[
"https://books.google.com/books?id=JUj81cN6nyAC&lpg=PA46&ots=_5LFnPx9E8&dq=Constitutional%20Convention%20in%201787%20judicial%20review&pg=PA46#v=onepage&q&f=false"
],
[
"http://digitalcommons.law.yale.edu/cgi/viewcontent.cgi?article=2019&context=fss_papers"
]
] |
|
50qtjv
|
why do some books have spiked, uneven page edges opposite the binding, whereas others are flat?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/50qtjv/eli5_why_do_some_books_have_spiked_uneven_page/
|
{
"a_id": [
"d768ryy",
"d768w5t"
],
"score": [
21,
6
],
"text": [
"This is called a deckled edge. It's a stylistic choice that makes the book seem older. Printing technology used to produce pages with an uneven width by default, but today this only happens as a result of an intentional aesthetic choice.\n\nThink of it as the book equivalent of distressed wood floors or jeans that are manufactured with holes in them.",
"This is called a \"deckle edge\". It's an aesthetic choice by the printer that made that run of books, replicated a past where all books were printed that way. There's some contradictory information about exactly why older books were like that (whether it's because they were printed \"uncut\" versus other reasons) but you can find [one set of ideas here in this old r/books thread.](_URL_0_)"
]
}
|
[] |
[] |
[
[],
[
"https://www.reddit.com/r/books/comments/jqn72/what_is_the_point_of_deckle_edge_paper_for_books/"
]
] |
||
1ujv8l
|
the economic and social argument why capitalism is better than all alternatives?
|
Why is capitalism preferred to all other kinds of ideologies? Economically speaking, is it more prosperous? What about socially and politically?
Can something like communism ever be argued as more economically beneficial than capitalism?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1ujv8l/eli5_the_economic_and_social_argument_why/
|
{
"a_id": [
"ceixqic",
"cej4ewn",
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"score": [
56,
17,
6
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"text": [
"Well I think a good way to answer this question is to look at those that defend capitalism, and those that defend other economic systems. There are definitely exceptions to the rule, but those who tend to love capitalism, are those that are doing well in it. That's the middle class and up. Those below middle class don't get too much air-time. You can look at the way capitalism works to see why only those two groups might be in favor.\n\n1. Capitalist invests money into starting business by buying the means of production.\n2. Capitalist hires workers at fixed wage.\n3. Workers create surplus.\n4. Capitalist takes surplus, some as profit, some to reinvest in the business, for still more profit.\n\nThe important thing to note here is that the workers are hired at a fixed wage, yet they create a surplus. That means the labor of the workers is worth *more* than they are paid. This means that the labor of the capitalist is worth *less* than they are paid. Repeat this process over a few cycles, and wealth is generated for those that are paid a wage plus profits, or those that are only paid in profits (investors).\n\nSo it's obvious why the upper class would be in favor of this system. It generates wealth through the work of others. The middle class is interesting because they're technically paid a wage, but they're paid just enough to supplement their income through investments. They're kind of in the middle group between the wage labor force, and the capitalists.\n\nIf you ask those that are squarely in the working class, you'll find a lot more varying opinions about capitalism, because they're they people that generate wealth for other people, but receive none themselves.\n\nAnother reason people defend capitalism is that it's been ingrained into American culture through Cold War propaganda and what not. Look at any /r/AskReddit thread with a title that says \"What works great in theory but not IRL\", and the top answer is usually \"Communism\". Ask them why and they'll probably say something along the lines of \"human nature\", ask them to clarify that, and you won't get an answer. Most people can't even define the words or systems, they're just taught from a young age to reject anything that isn't good ol' American Capitalism.\n\nIf it's not painfully obvious to you, I don't think capitalism is the best system, but I can explain why some people think it is.",
"[The myth of capitalism debunked in 5 seconds]( _URL_0_)",
"Capitalism is a circlejerk based doomsday device. \n"
]
}
|
[] |
[] |
[
[],
[
"https://www.youtube.com/watch?v=wJLaRhTKzw8#t=1m22s"
],
[]
] |
|
2fky5q
|
- why do i keep hearing the same scream of a man dying in films? ive heard it so many times.
|
Is there some secret reason the same sound bite is always used? Seen in the likes of kill bill and Star Wars
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2fky5q/eli5_why_do_i_keep_hearing_the_same_scream_of_a/
|
{
"a_id": [
"cka7x34",
"cka7xwj"
],
"score": [
2,
7
],
"text": [
"It's called the [Wilhelm Scream](_URL_0_). The first clip in the video is the original.\n\nIt's kind of a tradition.",
"You're probably hearing the [Wilhelm Scream](_URL_0_).\n\nIt's a stock sound effect, but also one so used that at this point it is actually used explicitly because of its relative notoriety. Sort of a tongue-in-cheek bit. \n\n"
]
}
|
[] |
[] |
[
[
"http://youtu.be/cdbYsoEasio"
],
[
"http://en.wikipedia.org/wiki/Wilhelm_scream"
]
] |
|
34rkym
|
What was the French public opinion of Napoleon during his autocratic reign? He was certainly loved before his coup.
|
He had support before he came to power because of his immense success as a general of the French Republic, even saving the Revolution at one point.
Howerver, becoming the sole autocratic leader of France runs against the ideas of the Revolution. What was public opinion like after his coup and onward, and how did it change from before then?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/34rkym/what_was_the_french_public_opinion_of_napoleon/
|
{
"a_id": [
"cqy03o7"
],
"score": [
3
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"text": [
"This is a broad question and I'm only going to focus upon the Brumaire coup itself and leave the Empire to others.\n\nNapoleon was arguably the most popular general in France by the time of the Brumaire coup in 1799. He already enjoyed great fame from the Italian campaign in which his victories led him to dictate a peace treaty to Austria, but Napoleon's skillful management of public relations of his Egyptian campaign magnified his fame. Although the Egyptian campaign was in many respects a strategic disaster for France, Napoleon managed to carefully edit the news coming to France about his accomplishments. This built up Napoleon's personal mystique so much that many in France acclaimed him as a popular hero when he returned in France. \n\nSubsequent Napoleonic mythmaking and propaganda would emphasize this popular support and present his assumption of power as a *fait accompli*. However, Napoleon was only one of several popular generals that various conspirators within the Directory were hoping to use to kill off the existing French government. Emmanel Sieyès, one of the key plotters in Brumaire, would famously quip, \"I need a sword,\" in other words, a man who could command the loyalty of one of the few powerful institutions that possessed a great deal of popular legitimacy within the Republic, the army. Bernadotte, a general and Minister of War, was the favorite of the Neo-Jacobin factions that wanted to reestablish the Revolution's leveling tendencies. Jean-Baptiste Jourdan toyed around with many different factions. Lazare Hoche, who enjoyed almost as much fame as Napoleon had unfortunately died of tuberculosis before Sieyès's initial soundings towards him could bear fruit. Jean Moreau, the youngest general in the army, refused to compromise himself with politics despite entreaties to do so. \n\nNapoleon was aware of this politicking behind the scenes and very carefully cultivated his image as an apolitical general. Aside from Napoleon's martial triumphs, which were much more prestigious than both Jourdan's and Bernadotte's, this purported apolitical character of Bonaparte put him at a more advantageous footing than his rivals. There was an apprehension amongst some of the plotters against vulgar militarism and somewhat vain generals like Bernadotte did not dissuade them of these fears. Here Napoleon's connection with Talleyrand paid dividends and the latter was able to assuage the Sieyès faction that Napoleon was an apolitical soldier concerned about the integrity of the state. \n\nIt is also important to realize the the result of the Brumaire coup, the Consulate, did not at first seem to be at odds with the precepts of the French Republic. The Consulate had a strong executive, but the First Consul in theory had checks on his power. In practice, Napoleon managed to sideline the other two Consuls very quickly and accumulated more power to the central executive. While this transition to a dictatorship put him at odds with some republicans within the state, the fact that Napoleon was able to finally introduce stability and a degree of competence within the French state allowed him to gain a great deal of popular legitimacy despite an apparent betrayal of the ideals of the Revolution. Napoleonic propaganda of the Consulate would actually accentuate the ideal that he personified the meritocratic and democratic ideals of the Revolution since he was a minor figure from the provinces that managed to rise up to the highest position in the land by virtue of talent and genius. Napoleon's victories in the field and his domestic initiatives like the *Code Napoleon* and the Concordat with the Papacy gave him a further patina of legitimacy that prior post-Revolutionary regimes had lacked. The Peace of Amiens in 1803 seemingly returned the continent to a period of peace that it had not known for nearly fifteen years which further added to Napoleon's popularity. The problem was Napoleon could never really make good on the promise of returning France and Europe to a state of normality and Napoleon's legitimacy became increasingly hostage to his military triumphs. Military victories began to pay less dividends within France after his invasion of Spain and sapped away at Napoleon's popularity within the country. Although he remained popular within certain French institutions like the army, Napoleon's legitimacy waned in many regions of France and led him to have a very precarious basis of popular support when military fortunes turned against him in 1813. \n\n*Sources*\n\nDwyer, Philip G. *Napoleon: The Path to Power*. New Haven, CT: Yale University Press, 2008. \n\nWoloch, Isser. *Napoleon and His Collaborators: The Making of a Dictatorship*. New York: W.W. Norton, 2001. "
]
}
|
[] |
[] |
[
[]
] |
|
20kicl
|
why can't aircraft flight data be stored online, like the icloud?
|
Could all the data recorded on the blackbox not be stored online? This would eliminate the risk of not finding it/ it being damaged.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/20kicl/eli5_why_cant_aircraft_flight_data_be_stored/
|
{
"a_id": [
"cg44nby"
],
"score": [
3
],
"text": [
"It can, but have your forgotten that \"the cloud\" and \"data anytime, anywhere\" is actually a pretty recent thing?\n\nUntil someone makes it law, or planes start to disappear more regularly, there's no incentive for anyone to spend the money to make it happen."
]
}
|
[] |
[] |
[
[]
] |
|
3w559z
|
humans having unprotected sex can very easily contract stds. wild animals on the other hand always have unprotected sex and ive never heard of an std epidemic. why?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3w559z/eli5_humans_having_unprotected_sex_can_very/
|
{
"a_id": [
"cxtg5ga",
"cxtg5y8",
"cxtg97l"
],
"score": [
7,
4,
2
],
"text": [
"Check out Koala chlamydia. It's actually a really big problem with them; it has been in the news not so long ago.",
"Because people generally aren't very concerned with animal STDs and you aren't a veterinarian or zoologist so you've never looked into the subject.\n\nAnimal STDs do exist.",
"Because you're not looking in the right places.\n\nThe Koala population has declined markedly in the last decade and Chlamydia is believed to be at least partly responsible. Infection rates may exceed 90% in some populations and it often renders them infertile.\n\n"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
2wmqnh
|
Curious about the evolution of the "everyday shower" as a societal norm. Id love to know about when, where, and how fast showering went from a luxury, to an everyday must.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2wmqnh/curious_about_the_evolution_of_the_everyday/
|
{
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"cosogo9"
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"text": [
"Moderator reminder:\n\nI have already had to go through and clean out this post multiple times. Do not post comments that rely totally on *personal experiences*. Also do not post conversations about modern cultural bathing practices, including the differences in average weekly bathing sessions between countries.\n\nThis question is about the development of high-frequency bathing, please limit responses to that topic.",
"The modern (relatively stringent) social expectations for cleanliness are in large part driven by the kind of mass advertising that got its start around the turn of the 20th century (books describing such [here](_URL_1_) and [here](_URL_0_) ). This was further spurred on by the [Social Hygiene Movement](_URL_2_) among the many Progressivist programs around the 1920's. The Social Hygiene Movement was primarily an effort to curb the rampant spread of venereal disease in a rapidly urbanizing America, and though it was medically off-base in that respect, these two forces continue to influence our modern notions of cleanliness today.",
"In what society? Upper- class Americans? Middle-class Spaniards? Working-class Italians?",
"As far as eastern regions go, Indians had daily bathing rituals modified to their social strata and class. Evidence can be seen right from the earliest scriptures (from around 1500 BC - Rk Veda - one of the oldest religious texts in the world, the Brihadaranyaka, the Manu Smriti, and the Dharmashastras). Mythology as well, with it being transparently clear by the time of the Ramayana and the mahabharata (both epics, called \"histories\" in a sense) that bathing was a daily act.\n\nNow this was perhaps because ritual purity is an emblematic aspect of Hinduism. Religion infuses every aspect of life, and therefore being ritually pure was a necessity that could not be avoided : the upper strata needed to be 'pure' in order to establish dominance and legitimate their hegemonic control of both the masses and other ceremonial control of rituals (the latter leads to the former), and the lower strata _had_ to be ritually 'pure' because they would not get to serve the upper class (and therefore not be able to survive, due to lack of work, constrained resources, and social castigation).\n\nThere is also some evidence of bathing and general cleanliness leading to higher success in avoiding diseases and death. \n\nSource: some parts from Hindu Ethics: Purity, Abortion, and Euthanasia By Harold G. Coward. ",
"Too add to this, how come people did not really understand hygiene? surely having clean hands and skin was much preferable to being dirty all the time?",
"To better answer your question, there needs to be a distinction between the term \"showering\" and \"bathing\". Bathing rituals have come a long way since 19th century America, and methods of cleaning oneself evolved as technologies, like indoor plumbing, become more widespread. The concept of cleanliness in staving off disease also becomes more prevalent with the outbreak of Small Pox and Yellow fever at the turn of the century. \n \nConsider a mid 19th century farmhouse. The main source of water came from a well or spicket outside of the home. Pitchers and basins would be filled with water and people would wash parts of their bodies (primarily their hands and face) while standing. If a home had a bathtub it would be filled in the same way, perhaps some water would be heated first over a fire, and family members would share the bath water. Because bathing was a domestic activity, the responsibility of the family's cleanliness fell to the mother/woman of the household. \n \nBehavioral conduct or etiquette literature, like [*The American Woman's Home* (1869)](_URL_0_) was written for a female audience and instructed them on how to maintain a socially acceptable *Christian* home. According to this primary source, the authors refute the idea of immersing your whole body in a bath, stating that \"a wet towel , applied every morning to the skin, followed by friction in pure air, is all that is absolutely needed\" (Beecher and Stowe, 156). The use of warm water is also not as popular as cool baths, because of scientific postulations that cool water helps in reducing fevers and thus is more beneficial to one's overall health. Keep in mind that this is only one view of the era and indoor plumbing was making its way into more homes. \n \nIn Kathleen Brown's work, *Society and the Sexes in the Modern World : Foul Bodies : Cleanliness and the Making of the Modern Body*, she suggests that the concept of cleanliness, conjured up by the white middle class, was directly associated to one's virtue and subsequently their position within society, which created two general factions, \"the diseased and morally dissolute and the healthy and morally wholesome.\" (Brown 363) However, during the mid-19th century there is still some contention about whether submerging your entire body was wise. Brown notes a 1825 University of Pennsylvania physician, William Dewees, and how his medical advice on bathing \"resonates with people willing to wash their bodies while they stood in a basin but unwilling to immerse themselves fully.\" (Brown 211) \n \nAnother book that discusses cleanliness as a civilizing tool is [*Sickness and Health in America: Readings in the History of Medicine and Public Health*](_URL_2_). It follows the ideology that cleanliness is an indicator of one's moral capacity. Evidence of this is the \"first successful indoor public bathhouse\" (487), which opened in New York in 1891, and displayed the phrase \"Cleanliness is Next to Godliness\" (488) at its entrance. Dirt and odor were synonymous with immorality. To be an outstanding citizen one must show their virtuous superiority by staying clean. \n \nTo address your specific concern with showers, [here](_URL_1_) is a very brief history on the shower's emerging popularity in the home. With the growing concern with cleanliness and health at the turn of the 20th century and the coinciding advancement in technology, one could argue that bathing (or showering) became more routine by the 1920's. \n \n \n \nBeecher, Catharine Esther, and Harriet Beecher Stowe. *The American Woman's Home: Or, Principles of Domestic Science; Being a Guide to the Formation and Maintenance of Economical, Healthful, Beautiful, and Christian Homes*. New York: J.B. Ford and;, 1869. Print. \n \nBrown, Kathleen M.. Society and the Sexes in the Modern World : Foul Bodies : Cleanliness and the Making of the Modern Body. New Haven, CT, USA: Yale University Press, 2009. ProQuest ebrary. Web. 21 February 2015. \n \nLeavitt, Judith Walzer, and Ronald L. Numbers, eds. *Sickness and Health in America: Readings in the History of Medicine and Public Health*. Madison: U of Wisconsin, 1997. Print. \n \nEdit: To answer /u/ctindel 's inquiry about the phrase \"cleanliness is next to godliness\", it is first mentioned in a sermon of [Reverend John Wesley](_URL_3_) at the end of the 18th century. Most sources that I have found state that a direct quote cannot be linked to the bible, yet the concept itself predates Wesley. \n \nEdit: So glad to be gilded for something I genuinely enjoy doing. Thanks. ",
"Extra Question: How long would I have to not shower for before my hygiene effected my health? In the 1500s? In the 1800s? and 25 years ago?",
"Lucy Worsley's fun documentary about homes in the house and their evolution sheds some light on this. Most of the videos have been taken down on YouTube, so here's a private copy I use occasionally.\n\n_URL_0_\n\nNOTE: I am offering this in the spirit of Fair Use rights (for educational purposes to a limited audience for a limited time) but this video might still be taken down by YouTube whilst they review appropriate copyright law on the video.",
"Although this example doesn't reflect upon global tendencies, which would also be difficult to put all under the same hat, it does expand upon how marketing contributed to the every-day-shower standard within a specific cultural context that went through a major transition in the recent history.\n\nA Yugoslavian (or Serbian if you will) poet Duško Radović (1922-1984) is remembered saying\n\n > Subota je dan kada se kupaju muževi koji vole svoje žene.\n\nor in English, \"Saturday is the bathing day for husbands who love their wives\", reminding us that even in modern day history of the 2nd half of 20th century it was not uncommon for people to only bathe once a week. This practice is heavily dependent on the regional cultural context of an average Yugoslavian man's everyday life: work from 6am to 2pm, go home, take a nap, and spend the evening having dinner, watching tv and being around the house. In socialist Yugoslavia it was not that common to be very outgoing, so you would usually spend your week working either in a factory or in an office and be home for the remaining time, so there was also no necessity to smell like morning dew all the time. At the same time, a socialist country such as Yugoslavia praised work and collective work ethics above anything else.\n\nRadović's quote also implies something other than that one should be a clean husband for his wife, and that is that if you were to bathe more than once a week, you were obviously someone who had evening plans, and thus not to be trusted. It was a wide understanding that a faithful and decent, moral man would spend his evenings home, because other options mainly included going to taverns (there were theaters and and cinemas of course, but there was a huge gap in cultural education between the cultural elite and an average working man).\n\nYouth started going out increasingly after Tito died (1980), which was coincidentally just around the time when New Wave music started blooming in Yugoslavia (1979). A personified moral standard gone, with a new culture fighting it's way through, resulted in youth enjoying life to the fullest, so everyday going out quickly became a standard. This seems a little too obvious, but with more outgoing came more mingling and flirting, for which you obviously wanted to also smell good.\n\nThe generational conflict of values in Yugoslavia from 1980 and onward is observed with unusual intensity. While U.S.A. has of course seen the grumpy old dad not understanding the ways of \"today's kids\", the Yugoslavian grumpy old dad in comparison soon had no moral or work standard to hold on to any more - a civil war broke in 1989 and a once country was shattered to barely functional state units with shaky economies, leaving many unemployed and even more disappointed that what they used to live by was now left in the mud to be further destroyed by boots of nationalism. The youth was now 10 years older, mainly not caring about either nationalism or the old socialist ways, and the youth that came after them continued going out more and more.\n\nWhen the last socialistic regime in the region, that of Slobodan Milošević in Serbia fell, within a year everyone started looking for new models of everyday life and many (secretly) turned to the youth as they were mostly unaware of the old ways. Middle age crisis spread like a disease and metrosexuals were everywhere. More new hair and body products came from the west.\n\nSo since 1989 and the Europe-wide fall of communist and socialist regimes is de facto responsible for the spreading of liberal market and intense media marketing that came from capitalistic countries, the fall of Berlin Wall really is responsible for people showering more often in the recent history of eastern Europe.",
"The modern shower requires a domestic heated water supply. In New Zealand that was starting to become widely available in the 1950s. [1951:](_URL_0_) \"No modern home is complete without an efficient hot water service. In this respect most New Zealand homes are by world standards particularly well equipped with hot water on tap to kitchen sink, laundry, bath and wash hand basin — some include a hot shower. The problem is to provide a really satisfactory flow of hot water for all these purposes as often as it is needed. \" \n\nIn 1971, in households that had hot water, 59% mainly or solely used the bath. 25% used the shower. \n\nBy 2005 that changed to 94% using, or mainly using, shower.\n\nSource: [Household Energy End-Use Project - Hot water](_URL_1_) page 255."
]
}
|
[] |
[] |
[
[],
[
"http://www.amazon.com/Clean-History-Personal-Hygiene-Purity/dp/0199532087/ref=pd_cp_b_1",
"http://www.amazon.com/Stronger-Than-Dirt-Advertising-1875-1940/dp/1573929522",
"http://en.wikipedia.org/wiki/Social_hygiene_movement"
],
[],
[],
[],
[
"https://books.google.com/books?id=Z2AEAAAAYAAJ&printsec=frontcover&dq=the+american+woman%27s+home&hl=en&sa=X&ei=XYzoVMbOG4arNo6bhJAL&ved=0CB8Q6AEwAA#v=onepage&q=bathing&f=false",
"http://www.homethingspast.com/vintage-antique-showers/",
"https://books.google.com/books?id=6eOlhNkjXaAC&source=gbs_navlinks_s",
"https://books.google.com/books?id=tI9KAAAAYAAJ&pg=PA123&dq=cleanliness+is+next+to+godliness+john+wesley&hl=en&sa=X&ei=evLoVPGmKILYggTw94JA&ved=0CB0Q6AEwAA#v=onepage&q=cleanliness%20is%20next%20to%20godliness%20john%20wesley&f=false"
],
[],
[
"http://youtu.be/34ZX--HYCMg"
],
[],
[
"http://nzetc.victoria.ac.nz/tm/scholarly/tei-Arc03_06DesR-t1-body-d8.html",
"http://www.energymonitor.org.nz/heep-final-hotwater-contents"
]
] |
||
28o3ao
|
If lightning wants to ground taking the shortest path, then why does it travel in a zig-zag?
|
As opposed to traveling in a straight beam-like shape?
|
askscience
|
http://www.reddit.com/r/askscience/comments/28o3ao/if_lightning_wants_to_ground_taking_the_shortest/
|
{
"a_id": [
"cicuxm6",
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"score": [
3,
2
],
"text": [
"Lightning wants to take the path of least resistance, rather than the shortest path. \nSo, when you see a zig-zag, it's \"searching\" for the path of least resistance by travelling through molecules in the air that provide the path of least resistance.\n\nCan probably get a better idea by examples of circuits, try looking up Ohm's law.",
"Think of it kind of like Plinko on the Price is Right. Gravity says the ball should go straight down, but it is encountering obstacles along the way. The electricity wants to get to the ground, but is encountering obstacles (areas of increased resistance) along the way. So it bounces along a pathway of lower resistance. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
21ve5t
|
At the rate stars are forming in the milky way, what are the chances humans will witness new light from a young star appear?
|
askscience
|
http://www.reddit.com/r/askscience/comments/21ve5t/at_the_rate_stars_are_forming_in_the_milky_way/
|
{
"a_id": [
"cgh97w9"
],
"score": [
2
],
"text": [
"The star formation rate (SFR) of the Milky Way is estimated to be ~ 2 solar masses per year. ([Source](_URL_0_)). So naively, one might say it is very likely.\n\nHowever, this SFR is an average and you should not interpret it that there are 2 stars being born in the Milky Way consistently each year. Star formation occurs in dense molecular clouds that collapse. Over a long time, in this cloud, many stars will form, some very light, some very massive.\n\nOn top of that, these star forming molecular clouds, typically also contain a lot of dust. This dust will block a lot of the optical light, making it much harder and more unlikely to suddenly see a star start fusing hydrogen and emitting light."
]
}
|
[] |
[] |
[
[
"http://iopscience.iop.org/1538-3881/142/6/197/pdf/aj_142_6_197.pdf"
]
] |
||
94lj37
|
the difference between chemical and biological weapons
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/94lj37/eli5_the_difference_between_chemical_and/
|
{
"a_id": [
"e3lw793"
],
"score": [
10
],
"text": [
"In basic terms, bioweapons are just living things used as weapons (or close to living, since there is some debate as to whether or not viruses are truly alive). So, bacteria, fungus, viruses, insects even, all count as bioweapons if they're being used to attack somebody. They don't necessarily have to be infectious or spread, they just have to be alive (or a virus).\n\nChemical weapons use chemicals with toxic properties. They're different from bioweapons because they're not alive, and they're different from conventional weapons because the chemicals in question are used for their toxicity, not because they explode or whatever."
]
}
|
[] |
[] |
[
[]
] |
||
2xnkgh
|
Do microphones record audio in a similar way to cameras, as in frames per second?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2xnkgh/do_microphones_record_audio_in_a_similar_way_to/
|
{
"a_id": [
"cp1qmv4",
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],
"score": [
3,
20
],
"text": [
"Microphones don't record audio any more than a lens takes a picture. Whether the recording is analog or digital depends on the recording device. ",
"Simple answer. The MICROPHONE does not. Your COMPUTER does.\n\nYou can make microphones in lots of different ways, but one that you could make sitting as your desk is like this. You just need a good magnet and a coil of wire. The pressure waves that are sound need to vibrate *something*, usually called a diaphragm, that then is joined to the coil of wire. When the wire moves through the magnetic field of the wire, it causes electrons to move in that wire. This causes a voltage. Note, this is basically the same thing as a speaker, except in a speaker, you make the voltage, that the causes the diaphragm to move, rather than the other way around.\n\nNow, at this point you have a voltage that is continuous in time. What I mean by that is that at any two time points you choose, you can always measure a voltage BETWEEN those two time points. The is of course different from from theoretical \"frames per second\" where you cannot ask \"what is between frame 1 and 2?\"\n\nHowever. In order for your computer to store the information, it needs to sample the voltage. And so your computer does. It could sample the voltage once a second, or 1000 times a second, or really at almost any rate. However, there is a law that says, if you sample a X samples per second, then the highest frequency in your data is X/2 Hz. Most human hearing only goes up to 10 kHz, and maybe up to 20 kHz... so it was decided that the standard sampling rate should be 44.1 kHz (why it wasn't decided to be 40kHz was down to some technical stuff that doesn't matter here).\n\nThus, the \"frame rate\" of most digital audio is 44100 \"frames\" per second.\n\nIt's worth noting that this only needs to apply to digital audio. Theoretically, one could record analog signals onto vinyl, that would never have passed through any digital systems. However, nowadays basically all (all?) sound is digitized at some point during the recording procedure. Though this effect can still be seen in recordings, because studio recordings are often made at 96kHz. See [here](_URL_0_). Though, as I said, human hearing only goes up to 10/20kHz, so the ability of playback to give you a 40kHz sound may not infact make your listening experience any better (and I would say, not, because your average set of speakers, even audiophile tweeters, will not be able to play 40kHz sound)."
]
}
|
[] |
[] |
[
[],
[
"https://www.youtube.com/watch?v=4eC6L3_k_48"
]
] |
||
1r2h4z
|
How did the Arabs feel about the holocaust?
|
I'm not talking about modern arabs, but arabs in Palestine, Iran, Egypt and Lebanon during the prime of the Israeli-Arab conflicts.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1r2h4z/how_did_the_arabs_feel_about_the_holocaust/
|
{
"a_id": [
"cdixlny"
],
"score": [
35
],
"text": [
"Few things to note here.\n\n1) Iranians are not Arabs\n2) Israel was not a state when the holocaust was happening\n\nNow to answer your question. There are some cases of Jewish-Arab clashes growing in the Middle East due to the Zionist movement. An example of that is [Grand Mufti of Jerusalem](_URL_0_). However most Arabs were against Nazism.\n\nIt is hard to differentiate between Arabs view on the holocaust and Arabs view on Zionism. A lot of attacks on Jews by Arabs at that time were due to Zionism but could be seen as an anti-Semetic, pro holocaust view. \n\nHowever, there is a great deal of Arabs who were completely against the holocaust and the Nazis. A lot of Arabs saved Jewish families.\n\nHere is a list of events about this:\n_URL_3_\n_URL_1_\n_URL_4_\n_URL_2_\n\nEDIT: Another thing to note is that Arabs had bigger issues to deal with at that point (or what they thought was a bigger issue at that point). They wanted to be freed from the British and French Rule of the Middle East which also blurs a lot on those Arabs that did support Germany. Some Arabs supported Nazis because Nazi being powerful made England and France weaker which could help Arabs gain their independence from them. It is pretty much why Arabs supported England in WW1, so that they can gain their independence from the Ottomans."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Grand_Mufti_of_Jerusalem",
"http://en.wikipedia.org/wiki/Great_Mosque_of_Paris",
"http://isreview.org/issue/74/arab-responses-nazism",
"http://en.wikipedia.org/wiki/Khaled_Abdul-Wahab",
"http://en.wikipedia.org/wiki/Arab_rescue_efforts_during_the_Holocaust"
]
] |
|
19rcb7
|
Are human beings closer to being on the smallest conceived scales of reality or the largest?
|
askscience
|
http://www.reddit.com/r/askscience/comments/19rcb7/are_human_beings_closer_to_being_on_the_smallest/
|
{
"a_id": [
"c8qmk7r"
],
"score": [
6
],
"text": [
"We can't really answer that question yet. A tau neutrino exists as about 2x10^-35 m. The universe is 4.3×10^26 m. The average human about 2x10^0 m. Arguably we are close to the big side of that. The problem is that we can't say with certainty if the universe is the largest thing or a neutrino the smallest. With what we know as of right now, humans are closer to the largest. "
]
}
|
[] |
[] |
[
[]
] |
||
8l185q
|
what is the difference between anglicanism and catholicism?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8l185q/eli5_what_is_the_difference_between_anglicanism/
|
{
"a_id": [
"dzc37s2",
"dzczx43"
],
"score": [
11,
2
],
"text": [
"The Head of the Church of England is Her Majesty Queen Elizabeth II.\n\nThe Head of the Catholic Church is His Holiness Pope Francis.",
"Worth mentioning that the Anglican Church is a subset of the Protestant branch of Christianity, other forms of Protestant Christianity are available and all share the single biggest difference, which is that the Pope is not considered to be God’s appointed head of Christianity on Earth."
]
}
|
[] |
[] |
[
[],
[]
] |
|
6nxhhr
|
why is it that when you ask someone to guess a number there's a high possibility it will be 7?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6nxhhr/eli5_why_is_it_that_when_you_ask_someone_to_guess/
|
{
"a_id": [
"dkczw7u"
],
"score": [
16
],
"text": [
"This is an interesting quirk of human psychology. Humans don't pick things at random, but they will try to. You end up with a weird situation when they pick the most 'random looking' number. Here's the general thought process:\n\n* Pick a number at random between 1 and 10\n\n* 1 is out, that's the lowest it's not random\n\n* 10 is out, that's the highest it's not random\n\n* 2 is out, and so are all the even numbers, they don't look random enough\n\n* 5 is out, that's exactly half way, definitely not random\n\n* 9 is out, it's three times three, totally not random\n\n* 3 is out, it divides 9 exactly, not random enough\n\n* 7 is most random. It's not even, it's not exactly half way, neither the biggest nor the smallest and isn't related to 9 or 3 in any way.\n\n[Here's a poll that backs up that seven is the most random.](_URL_0_)"
]
}
|
[] |
[] |
[
[
"http://www.misterpoll.com/polls/449086/results"
]
] |
||
1mmg9s
|
When neuroscientists say a part of the brain "lights up," what's actually going on?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1mmg9s/when_neuroscientists_say_a_part_of_the_brain/
|
{
"a_id": [
"ccan1bu",
"ccansqe"
],
"score": [
6,
2
],
"text": [
"They are likely talking about fMRI scans. fMRI = functional Magnetic Resonance imaging. It depends on the blood oxygen level signal (BOLD- blood oxygen level dependent). The theory behind his is basically that if a part of your brain is working hard, it's going to need a lot of energy. So it would make sense that the metabolic rates would need to increase in those regions. In order to do that, that area needs certain things like oxygen. So if its working hard, it would make sense that there would be a higher blood oxygen level. The machine lights these areas of increased oxygen level. So technically, fMRI is *not* directly measuring neuronal activity. It's only measuring it indirectly through the assumption that increased activity leads to increased local oxygen levels.\n\ntl;dr the lit up areas are the part of the brain that are working \"harder\" at the time.",
"Depends on the imaging technique used. If fMRI, we're talking about blood rushing to the area. If we're using ERP, we're talking about localization of electrical activity (neurons firing)."
]
}
|
[] |
[] |
[
[],
[]
] |
||
z0uex
|
AskScience: How is it physically possible for a planet to orbit twin suns?
|
As I'm sure many of you have read, [kepler has found two planets within a binary start system](_URL_0_).
Thinking about it practically I would think that the overlapping rotations of the two stars vs the orbit of the planet would cause too much feedback to create a stable system, unless the planets were rotating *perfectly* with the rotation of the stars themselves. So how does a system like this work?
|
askscience
|
http://www.reddit.com/r/askscience/comments/z0uex/askscience_how_is_it_physically_possible_for_a/
|
{
"a_id": [
"c60i23y",
"c60iu24"
],
"score": [
3,
5
],
"text": [
"If the two stars are much closer to each other than the orbit of the planet then it pretty much orbits as it does one star. From [this picture](_URL_0_) that basically looks like the case.",
"In addition to having a planet orbit a tight binary pair, you can have a planet around one star, with the second star further away (hundreds or thousands of AU)."
]
}
|
[] |
[
"http://www.huffingtonpost.com/2012/08/29/alien-planets-twin-suns-star-wars-tatooine-nasa_n_1838816.html"
] |
[
[
"http://i.huffpost.com/gen/749768/original.jpg"
],
[]
] |
|
5j2vnp
|
why is there a social stigma against prostitution and similar professions?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5j2vnp/eli5_why_is_there_a_social_stigma_against/
|
{
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"dbcx89g",
"dbcx8l7",
"dbd29qm",
"dbd30qf",
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],
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7,
65,
38,
58,
42
],
"text": [
"because of religious roots. back in the day, pretty much everyone was one religion or another. only recently have people been more uncaring for organized religion. ",
"Before birth control it was a profession that led to the creation of bastard children that society doesn't want to deal with. ",
"Sexually transmitted disease. \n\n\n\n\nThe stigma was established at a time when syphilis was a death sentence for women and especially for newly born children. \n\n\n\n\n\n\nThere's no reason to perpetuate the stigma now though since sanitation and disease management are well established fields. But, it's a difficult topic to debate in public and religious fundamentalists won't let the law change. ",
"I know the real answer to this, but you're not going to like it.\n\nTraditionally men took care of women, that is, a man would marry a woman, and he would hunt, or farm, or work, whichever was appropriate to the timeframe and region, and in exchange for this, the woman would do domestic work and raise the children. \n\nWhen you have women who are willing to have sex with men outside of marriage, you disrupt that social order. If men can get laid without entering into this social agreement, that means many men won't want to get married and support a wife and kids. \n\nThat leaves unmarried women who traditionally were not allowed to work or own property with no one to take care of them. The reason why prostitution was illegal and other women \"shamed sluts\" was to keep the social order. \n\nNow that women can have jobs and use birth control, views are beginning to change, that's why we now have things like Tender and Netflix and chill.",
"Historically, virgin females had a high social worth, but had to repress their desires to keep it. With higher social worth came elevated status, and those that are socially elevated naturally came to look down upon and despise those below them. Women that sold their bodies for money were seen as the most worthless by those that didn't, and by keeping it this way, ensured that their high worth was maintained. We continue to see this today with \"slut shaming\" and other forms of social stigma to maintain high perceived social worth."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
||
bq5795
|
Was Hitler compared to someone ?
|
Nowadays, everyone is compared to Hitler.
But back then, was Hitler compared to someone who lived before him ?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/bq5795/was_hitler_compared_to_someone/
|
{
"a_id": [
"eo1rjbj"
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"text": [
"Prior to the arrival of Godwin's Law, and the inevitable conclusion of comparing all things to Hitler, during his own rise, Hitler was compared to many people, both real and imagined. Gavriel D. Rosenfeld kindly has done much of the legwork in providing what is the up to what is perhaps the most comprehensive study of this niche topic, and breaks down the comparisons into several broad groups, although they were not entirely exclusive:\n\n* Ancient tyrants and conquerors\n* So called “Barbarian” warlords\n* Medieval and Early Modern religious fanatics\n* Modern dictators \n* Mythical figures\n\nThe specific 'class', and specific figures within it, were often drawn on to illustrate specific themes, and the favor shown to certain ones over others often shifted through Hitler's rise and rule.\n\nFor instance, in his early days, prior to coming to power, it wasn't uncommon to compare Hitler to his future second-fiddle, as Benito Mussolini, installed in power in 1922, to many commentators figured are a fairly obvious point of comparison, least of all given Hitler's quite explicit attempt at emulation of the March on Rome with his own failed 'Beer Hall Putsch'. A few commentators of the time drew comparisons to the 19th century French populist Georges Boulanger, whose movement had almost lead to a coup in the late 1880s, and in the violence of Hitler's rhetoric, the ghost of another Frenchman, Maximilian Robespierre, was raised by some, a parallel with of The Terror with possible promises of the same befalling Germany.\n\nAs far as real people went though, one of the most popular, and enduring, of comparisons would be to Napoleon I (Napoleon III too, occasionally, especially in the early days of power where their paths seemed similar to some). This was especially popular with the British, and Churchill specifically but by no means exclusively. Framing the two as similar in their desires for domination and conquest, likewise Britain could be framed as the plucky little country that would be underestimated, and save Europe.\n\nOther historical figures too were brought out. Attila the Hun and Genghis Khan for instance both figured as rough analogies for the images of fire and destruction that they brought to the popular imagination, and the same that Hitler was bringing to Europe, and Nero was used a few times in the wake of the Reichstag Fire, harkening back to the alleged fiddling while Rome burned. \n\nEspecially in the latter part of Hitler's reign, more apocalyptic language became common, and no more so than Satan himself, which had been something of the 'go-to' incarnate of evil before Hitler took his place in the popular consciousness (although that certainly also just says something about secularization of society). The Lord of Lies was joined by any number of other forms such as the Antichrist, but more erudite writers brought in comparisons such as Loki in the context of *Ragnarok*, and also less known ones like Sciron, a figure I had to look up, and apparently the demigod who Theseus killed, and \"killed travelers by kicking them off a cliff\".\n\nThis is *far* from exhaustive, to be sure. The biggest name, probably, should be Napoleon, although of course the comparison has flipped and now some instead call him the “the 18th century Hitler.” It isn't an entirely fair comparison of course, which breaks down in many points and thus requires focus on only specific threads, but of course, some worried too about that, with some writers warning that it was important *not* to let Hitler's memory be rehabilitated in the same way that of the first 'Little Corporal' had been. Nevertheless though it is, again, a lasting one that remains even today, although even the book *Napoleon & Hitler: A Comparative Biography* is quick to note that whatever the 'inescapable resemblances', \"no one will dispute that Hitler was more evil than the Emperor, did evil on a far greater scale.\"\n\nAll in all, the point to be made is that many different figures were used, some briefly, others enduringly, some fairly and others not. The whole point of an analogy of course is that it *isn't* perfect, but rather allows an easy to understand comparison to be drawn, and that is what so many of these in the end served. I've only provided a small smattering of examples, and I would encourage anyone interested to check out Rosenfeld's paper as it is much more deep than my comparatively brief summation ([also check out his AMA!](_URL_0_)), but I *will* be editing in an appendix as I go through the paper again and try to list all of the names that he makes mention of...\n\nRosenfeld, Gavriel D. 2018. “Who Was ‘Hitler’ Before Hitler? Historical Analogies and the Struggle to Understand Nazism, 1930–1945.” *Central European History* 51 (02): 249–81.\n\nSeward, Desmond. **Napoleon & Hitler: A Comparative Biography*. Thistle Publishing, 2013.\n\n**Appendix**: Hitler was like...\n\n* Georges Boulanger\n* Maximilian Robespierre\n* Napoleon III\n* Henry VIII,\n* Philip of Macedon\n* Attila the Hun\n* Genghis Khan.\n* Pharaoh (of the Bible)\n* King Nebuchadnezzar II of Babylon\n* Haman of Persia\n* King Antiochus IV\n* King Herod of Judea\n* Julius Caesar\n* Emperor Nero\n* Alexander the Great\n* Hannibal of Carthage\n* Alaric the Visigoth\n* Genseric the Vandal\n* Tamerlane\n* Girolamo Savonarola\n* Tomás de Torquemada\n* Jan Bockelson\n* \"French Catholic perpetrators of the St. Bartholomew’s Day massacre\"\n* Oliver Cromwell\n* Napoleon Bonaparte\n* Satan\n* Lucifer\n* Beelzebub\n* The Antichrist\n* Mephisto\n* Benito Mussolini\n* Richard III\n* HRE Charles V\n* Emperor Theodosius\n* Icarus\n* Sciron\n* Caligula\n* Tiberius\n* Sisyphus\n* Wotan\n* Loki"
]
}
|
[] |
[] |
[
[
"https://old.reddit.com/r/AskHistorians/comments/8r3e5x/i_am_gabriel_rosenfeld_professor_at_fairfield/"
]
] |
|
4s08z8
|
Is it possible some Europeans visited the Americas long before the Vikings or Columbus and simply never wrote about it?
|
Couldn't someone with a ship just go on their own trip without the mandate of a King and just go exploring? That's what people did back then didn't they? They'd explore?
Maybe some odd objects found in America with distinctly Roman Anglo styles and features which predate known trips to the Americas were from people who visited without telling anyone.
People who just crossed the Atlantic on their own.
???
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4s08z8/is_it_possible_some_europeans_visited_the/
|
{
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"text": [
"In Salt: a World History, Mark Kurlansky suggests that cod fishermen could have discovered Newfoundland and its massive cod fisheries as early as the mid 15th century. The reasoning for not relaying this discovery would be the intense competition for fishing spots between rival companies. Whether or not the theory holds ground is up for debate but the idea is interesting and should be noted. For more earlier discoveries see The Vinland Sagas for the Norse discovery of America which is very well documented, with archeologists finding their temporary settlement in L'Anse aux Meadows in Newfoundland ",
"There's always room for discussion, but perhaps the section [Travel and contact across the Atlantic before Columbus](_URL_0_) in our FAQ will answer your inquiry."
]
}
|
[] |
[] |
[
[],
[
"https://www.reddit.com/r/AskHistorians/wiki/nativeamerican#wiki_pre-columbian_trade_and_contact"
]
] |
|
a6h6by
|
why we still need to do the whole "left eye/right eye, option 1 or option 2" when getting glasses? why isn't there a machine that can test this just by looking at our eyes?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/a6h6by/eli5_why_we_still_need_to_do_the_whole_left/
|
{
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"text": [
"There are now. My optometrist has a “pre-test” that gives a ballpark range to the classic machine they put on you. So instead of an unending series of better or worse, you read a line and have one or two corrections. ",
"Vision is a really subjective experience, affected by many factors including the exact shape of lots of different parts of the eye. You've got two choices:\n\n 1. Get a complicated, expensive machine that gives you an OK pair of glasses; or\n 2. Buy a simple, comparatively cheap set of lenses, and check to see what lenses make it easier and harder to see until you've got a great pair of glasses.\n\nI know which I'd choose.",
"There is such a machine, which is the start, it measures how light passes through the eyes.\n\nHowever, sight isn't just the eyes, they need to get positioned by ocular muscles, then what You see is transmitted to the brain and only then can one see it.\n\nImagine You have perfect eyes but a minor obstacle on the way to the brain. Perfext machine result, not so perfect objective result.",
"Machinery can only calculate what is going on based on the shape and measurements of your eyes, how your brain has developed to attempt to self-correct isn’t predictable by machinery and so one or another method of correction will be better than the other. "
]
}
|
[] |
[] |
[
[],
[],
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||
94qvqb
|
What, if anything, was behind the limited range of given names in Tudor England?
|
I'm thinking in particular of the sheer number of Thomases -- off the top of my head, the court saw Thomas Wolsey, Thomas Moore, Thomas Cromwell, Thomas Howard, Thomas Cranmer and Thomas Wroithesley, all within a short period, and I'm sure I'm forgetting others. Or on the female side, for instance, Henry's queens featured one Jane but two Annes and three Catherines (with various spellings).
Was there a societal reason for this limited pallatte of given names, or is it primarily coincidence, or a combination of a relatively limited pallatte of names _and_ coincidence?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/94qvqb/what_if_anything_was_behind_the_limited_range_of/
|
{
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"e3n5ot0"
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"text": [
"I've looked at this question from a couple of different angles, [the first of which](_URL_1_) is specifically about the name \"Thomas\" and opens with--I promise I did not just edit this in--the three Catherines, two Annas situation.\n\nI'll paste [the later answer](_URL_0_) here because's it more of an actual answer to your question, although my examples are German: \n\nYes! I love this question so much. When you look through the letter collection of Hildegard of Bingen in the late 12th century, her epistolarly correspondents and the people she mentions have names like Tenxwind (f), Richardis (f), Helengarus (m), Kuno (m). The only real trouble you'll have with overlapping names is keeping the various royal Henries in line. When you look at 16th century cities, the most popular boys' name is Hieronymous (Jerome) after the late antique philologist-theologian and everyone else wants to name their kid Desiderius after Erasmus.\n\nIn between, the boys are all named the local version of John, Thomas, and Peter, and the girls are are Elisabeth, Mary, Margaret, Katherine, Anna, or Barbara.\n\nThere were two major forces at play in the homogenization of first names (because this is also the era when personal names were becoming \"first\" names\"), both of which stem from the deeper Christianization of the laity of the course of the later Middle Ages.\n\nThe first trend and underlying reason is the shift towards saints' names, and in particular, a certain subset of saints. Apostles' names stay very popular among men. We should think of these as coming out of the stories told about Christ's life rather than \"bible stories,\" specifically--a wider use of biblical names is more associated with the Reformed/Puritans later on.\n\nWith women, the so-called \"virgin martyrs\" of late antique legend achieve rockstar namesake status: Katherine (of Alexandria, defeated 50 pagan philosophers in oral debate), Margaret (of Antioch, the dragonslayer saint), Barbara (the Rapunzel saint). The \"life of Christ\" tradition also draws out a few: Anna, Elizabeth, Magdalena, and even Maria (although the last is not as common as you might think--the Catholic tradition of naming every daughter Mary _____ is rather modern). The popularity of Elizabeth, too, gets a boost from St. Elisabeth of Hungary in the 13th century, who became one of the two most popular saints among medieval women and especially religious women in the late Middle Ages (Katherine of Alexandria also represents well).\n\nThis is not a perfect rule, and variations are often regional. In Germany, the women's names of Adelheid and Gertrude remain tenaciously popular, for example, and I don't think you can put all the weight of those on 7C abbess St. Gertrude of Nivelles. Not sure where the popularity of \"Conrad\" came from, but presumably it wasn't anywhere good. The three Konrads that spring immediately to my mind (of Marburg, Kügelein, Peuttinger) were each despicable in some way (ALL the ways, no seriously all of them, everyone hated Conrad of Marburg; creeper on young virgin women; Toddlers & Tiaras dad). One assumes there were at least some Conrads who turned out normal.\n\nThe turn towards saints' names related to the rising presence of hagiographic legends (including the vita Christi genre) in later medieval culture, and possibly some superstition about baptizing a child with a saint's name being god for their salvation.\n\nBut there's a second step to consider in the winnowing down of most western Europeans' names--obviously there would always be some wonderful exceptions--to such a small group. It also relates to baptism, and it's the central role that godparents played in later medieval culture.\n\nGodparents as well as parents stood up for the baby at baptism, with all the same religious and upbringing requirements. In fact, the godparent relationship was considered so strong by medieval people that it counted for rules on incest and consanguinity.\n\n(Tangent: also the \"incest taboo\" is an anthropological commonplace, one of the interesting points that researchers make is that every culture defines what is \"incest\" somewhat differently, beyond the parent/child taboo. In medieval Europe, baptismal parents and the \"familial\" relationships established from that are a fascinating demonstration of this).\n\nThe importance of godparents and the connection with baptism, it seems, helped lead to a cultural fad of naming the baby after the godparents. And so one generation tended to pass its names down to the next.\n\nObviously, none of these are exact rules. The slate of common names is a little broader than I made it out to be (of course). And then there's always going to be the mom who insisted on naming her daughter Isolde after the Arthurian romance. Nevertheless, it's an interesting exercise to go through the \"Personenregister\" (people-index) of medieval letter collections or studies of convents and write down the occurrence of contemporary names. It's pretty revealing.\n\nA user in the other thread suggested that grandparents as well as godparents may have been a factor, but this is not generally something I see in my own sources. The role/presence of grandparents is harder than one might think to trace in the late Middle Ages. Although it's also possible that reflects a lack of attention in some cases, not just lost or never-written records. Albrecht Durer's biographers have suggested his parents *chose* godparents for their children based on what they expected the name to be, so it could be an indirect factor in some cases."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/62z39k/what_happened_to_the_given_namefirst_name_pool/dfqccs3/",
"https://www.reddit.com/r/AskHistorians/comments/3ph3b9/is_there_an_explanation_for_the_popularity_of_the/cw69ekr/"
]
] |
|
2omrsm
|
What happens to the last remaining atom in a lump of radioactive material?At which point does it disintegrate?
|
(from an article in the Journal of Heuristics)
#As this is different from the half -life prediction,shouldn't radioactivity be treated as an 'emergent' phenomenon?
#At which point is 'singleness' and 'manyness' achieved? We can vaporise the initial lump into single atoms -why does this give rise to a scenario different from the single lump?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2omrsm/what_happens_to_the_last_remaining_atom_in_a_lump/
|
{
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"cmorn8v",
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"text": [
"Half life is just a a way to represent the probability of an atom to decay. No matter how many or how few atoms you have in a system, each atom has a 50% chance of decaying in one half life. These events are all independent, so one atom doesn't change based on the other atoms in the system. However, since there are around 10^23 atoms in a common object, statistically very close to half of the nuclei will decay with one half-life. \n\nWhen you are only left with one atom, it has a 50% of decaying in one halflife, the exact same as it did when there were many atoms. it's possible for it to never decay, but each half life passed reduces those odds 50%. \n\nSo for radioactive decay, 'singleness' or 'manyness' is irrelevant, there is no difference. \n",
"The atom will decay with the same probability distribution in timing as the others, starting now...\n\nLonger version:\nRadioactive decay is (to close approximation) a Poisson process. What that means is that each atom has the same chance to decay in a given period. The half life of an element is the length of time for which that probability is 50%, ergo approximately half of a given sample will have decayed by then. However, the probability of any particular atom decaying over any future interval is not effected by how long it's waited up till now. That's why of the remaining 50%, approximately half will decay in the next half life, leaving about 25%. If a particular atom has a half life of 1 year, and has gone 100,000,000,000 years without decaying, the chance of it decaying in the next year is still exactly 50%.\n\nAs you get down to a countable number of atoms, the statistics becomes much more probabilistic, and much less about large averages. For two atoms, you can calculate seperate probabilities of still having 2, 1, or 0 particles at any given future time. They are always probabilities though. Indeed, there is always a non-zero probability of any one, or even all the atoms remaining in one state or the other. As the number and time increase, this probability quickly shrinks to become negligible.\n\nIf you plot the probability distribution for 2 or three atoms, it looks like a shaded checkerboard, growing thinner with time along a roughly logarithmic decline.\n\nAs you increase the number of atoms, the distribution actually becomes more uncertain in raw number-of-atoms terms, but more certain as a percent--the number of atoms grows faster than the variability. This common when taking any sum of independent probabilities. It's this statistical averaging effect that covers the ground between singleness and manyness. So effectively, if we continuously \"zoom out\" to see our whole plot, then it will appear to become more detailed, and the sides more focused until at very high particle count, it would appear to be a line, when all the way zoomed in.\n\nTo answer the final question: Half life defined as \"when half the particles decay\" is an emergent trend. Half life defined more rigorously as \"the time after which a particle will have a 50% chance of having decayed\" is very much a directly measurable quantity, from which the aforementioned emergent effect arises."
]
}
|
[] |
[] |
[
[],
[]
] |
|
4cklt8
|
why does city construction take so long? it seems like there are 100 projects that each get 10 guys.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4cklt8/eli5_why_does_city_construction_take_so_long_it/
|
{
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"text": [
"It depends on the project, but in general there is a lot more going on than you notice. Like for example there was a recent building built in my area. For the first 3 months or so it looked like almost nothing was really being done when in reality they where getting the foundation exactly perfect witch is 100% important for the rest of the building. Even if they where off by a slight calculation it would screw up the entire rest of the building. Adding huge costs and delays. Then for the next three week they where letting things like concrete set, staging everything, and waiting on specific machines and materials from some places that could be coming from up to 1,000 miles away. Then it was all hands on deck but you can only do certain things in certain orders, like you do not want to be craning steel beams to the 4th floor while there are windows in the first. ",
"There is also Occupational Health and Safety. You can't rush things. You don't want bits of metal or panes of glass falling on pedestrians below.",
"In every construction project, every large piece of equipment requires a user and someone to oversee it. I don't know how this applies to smaller equipment like jackhammers."
]
}
|
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[] |
[
[],
[],
[]
] |
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29f873
|
how close are we to stopping dementia/similar afflictions? are there any measures that can be taken to prevent them?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/29f873/eli5_how_close_are_we_to_stopping_dementiasimilar/
|
{
"a_id": [
"cikd41i",
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"text": [
"you asked the same question yesterday...",
"I believe that there is a lot of potentially very significant research underway that will offer hope to people with these conditions in the not too distant future, but they are sufficiently far off that there is still a lot of ground to cover. \n\nThe human brain is the most complex structure known to us in the universe, and hence implementing things to maintain or fix it are far from trivial.\n\nI have included a link below to an article that covers an example of where we are with treating these sort of issues:\n\n_URL_0_\n\n"
]
}
|
[] |
[] |
[
[],
[
"http://www.independent.co.uk/news/uk/home-news/alzheimers-treatment-breakthrough-british-scientists-pave-way-for-simple-pill-to-cure-disease-8869716.html"
]
] |
||
7napzl
|
How difficult would it have been for an American during World War I or World War II to avoid the draft by simply ignoring notices and moving around the country? How widespread was such a thing? Presumably this meant abandoning their identity from before the war?
|
Such a thing seemed as if it would be completely plausible, but how widespread was it? If it did occur, how zealous were prosecutions after the war was over when such people were found?
Before the institution of a national identity system, i.e. a social security card, it seems like it would have been pretty trivial to assume a new identity by just moving further away?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7napzl/how_difficult_would_it_have_been_for_an_american/
|
{
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"ds0fgl1"
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"text": [
"During Word War I, our case for going to war wasn’t nearly as strong as in World War II. The war was in some ways “forced”. There was a lot of protest.\n\nTo avoid this during World War II, a very robust system for “Conscientious Objectors” was set-up. You wouldn’t have needed to necessarily disappear at all to avoid war. You could take a non-combat role, go to work at a CCC camp, etc. There were CO’s during WWI, but not as many. Ironically though because the case for war was much stronger there was much less resistance than in WWI.\n\nAlso during WWI, only 10% of those registered (about 25 million) for the draft were drafted, so outright evasion would have been dumb unless your number actually got called.\n\nAfter WWII, Truman pardoned all draft resisters / evaders. There were 373,000, of which about 5% convicted until they were pardoned.\n\nSorry I couldn’t answer all of your questions, hope that sheds some light.\n\nSOURCE: The Military Draft Handbook by James Tracy\n\n\n\n\n"
]
}
|
[] |
[] |
[
[]
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7poon2
|
What are the origins of the LTTE and the related issues of the Tamil people in Sri Lanka?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7poon2/what_are_the_origins_of_the_ltte_and_the_related/
|
{
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"text": [
"This is a very long and complicated question that is still, even following the defeat of the LTTE in 2009, a sensitive topic. While it pushes up against the 20 year rule, I will do my best to stick to the conflict before 1997, though it will limit the discussion of the Tamil Tigers and the Śrī Lankān government's war crimes as well as the ongoing issues following that defeat. If you would like to learn more about that, I'd be happy (well, not happy *per se*, it is a bit of a somber topic) to follow up in a PM or you are welcome to post a question over at r/asksocialscience or /r/ask_politics (though neither are as thorough as this one.\n\nSorry this took so long, in my defense, it is something like 30 pages and by far my longest post here. I think I went a little overboard in the beginning and eventually ended up burining out towards the end, sorry for that. I will give more clarification later on and probably expand more on the role of international funding for the LTTE and the role of India and Dravidian Nationalism as well as war crimes committed by the Śrī Lankan government, but right now it is 2:15 and I've been working on this since it was asked. \n\n--------\n\n#Part 1: The Ancient History and Historical Justifications for the Conflict\n\nThe Tamil people have been present in Śrī Lankā, especially the north where it is not far from Tamil Nadu for a very long time, though not as long as some would claim. The original inhabitants appeared about 37,000 years ago and left behind caves. These were anatomically modern humans, likely from the coasts of India who migrated there by boat. They are likely the ancestors of the Vedda people of Śrī Lankā, of whom there are very few left.\n\nThe people who now dominate Śrī Lankā are the Sinhalese, who trace there ancestry to the legendary exiled Prince Vijaya and his retinue of 700 advisors. According to the legendary epic, the Mahāvaṃsa (Pāli: Great Chronicle), they were exiled for general \"evil deeds\". In any case the chronicle places them as being from present day Bengal and having obtained Pandya brides, which is confirmed by Genetic evidence.\n\nThe Tamils (specifically the Pandyas) may have had settlements on the island before the Sinhalese people (or rather the people who would become Sinhalese), but there is not archeological or textual evidence for it. The first evidence of Tamil presence occurs in the Mahāvaṃsa, backed up by inscriptions, slightly before the reign of Aśoka the Great in India. King Devānampriya Tissa, not to be confused with Aśoka who called himself Devānampriya, appeared to rule over a mixed kingdom, though he himself converted to Buddhism and patronized it. Years later, the Dravidio-Tamil king Eḷāra held control of the northern plains of Śrī Lankā after having taken over the Anurādhapura kingdom founded by the Vijaya dynasty, and the Sinhalese in the the south led by Duṭṭagāmaṇī of Rohaṇa. While the Mahāvaṃsa paints this conflict as one of the Buddhist Sinhalese people against the Brahminical Tamil usurpers, the evidence shows that it was far more complicated than just that.\n\nThe Sinhalese and Śrī Lankān Tamils both mixed quite a bit during the centuries and they both led mixed kingdoms. During the time of Eḷāra both kingdoms had a significant population of Tamils and Sinhalese. Thus the war was neither a holy war or a racial war like some modern commentators (and indeed the Sinhalese who wrote the document) have claimed. Nonetheless, the war established Sinhalese dominance over the whole island, something that would be essentially unchecked for eight centuries.\n\nEight centuries later, Śrī Lankā was fractured into two rival kingdoms, both of whom relied heavily on Tamil mercenaries and generals leading to a powerful Tamil aristocracy. In 642, Māhavamma took control and curbed the power of the rich Tamil aristocracy, though he still kept a retinue of Tamil mercenaries. However, Śrī Lankā was facing increasing military and economic pressure from the three kingdoms of South India, the Coḷas, Pāṇḍyas, and Pallavas.\n\nThese kingdoms were strongly militant and very Hindu. The Pāṇḍyas were the first to invade and held the northern coast, but were beaten back by the Sinhalese. However, at this time the Coḷas took control of Pallavan territory and the Sinhalese half-heartedly supported the Pāṇḍyan efforts to beat back the Coḷas, but were unsuccessful and eventually, the Coḷas took control of Śrī Lankā ending over 1 thousand years of Sinhalese rule. \n\nThe Tamil rule over Śrī Lankā was actually quite short, only a few years and not uncontested. However, the Coḷa's left a deep scar on the island and numerous places were never rebuilt. The Coḷas ruled over the north coast for some time and retained considerable influence over the island in terms of trade. The invasions (along with the fracturing of the saṅgha due to the arrival of Mahāyāna) nearly destroyed Buddhism in Śrī Lankā and the Sinhalese were forced to call upon the help of Pagan to restore Buddhism and regain the Pāli Canon. \n\nConflict between the Tamil Kingdoms (who would eventually gain independence Pāṇṣyas) from the Sinhalese Kingdoms would continue and range from violent war to a tenuous peace. However, this does not mean that relations between the Sinhalese PEOPLE and Tamil people was poor, even the relations between Buddhists and Hindus was fairly okay. In fact, during this period, there was a significant deal of syncretization between Hinduism and Buddhism, stating around this time, Hindu temples often contained Buddhist iconography and Bodhisattvas and Buddhist Temples often had Hindu Icons and Deities were worshiped.\n\nFurthermore, the relations between various religions was comparable to those under most contemporary Indian ones with powerful elites patronizing all sects. This encouragement of religious pluralism had a strong effect upon the local populace and led to generally friendly relations and little persecution overall.\n\nIn a somewhat confusing note, many of the Sinhalese in Coḷa (and later Jaffna) Tamil territory were \"Tamilicized\", converting to Vaiṣṇavism and adopting Tamil language and customs while Tamils in Sinhalese territory were \"Sinhalized\" and doing likewise. It is not an understatement to say that nearly all Sinhalese today have mixed lineage with Tamils and all Śrī Lankān Tamils have Sinhalese blood.^3\n\nAs we can see, there has been tension since Ancient times, but that tension is often overstated and wrapped up with both Tamil or Sinhalese-Buddhist Nationalism. I also skipped over the arrival of the \"Sinhalese Moors\", who are the descendants of Muslim traders and represent a significant minority in Śrī Lankā, they used to get along fairly well with people, but unfortunately have found themselves disenfranchised since the beginning of the current conflict.\n\n-----\n\n#Part 2: Portuguese and Dutch Rule: Suppression and Conversion\n\nBy the 16th century, Europeans had entered the scene like never before, attempting to take control of the fertile landscape and strategic location of the island. The first to do so were the Portuguese who quickly conquered the Northern and Western parts of the island but ran into difficulties maintaining a proper hold over it. The Portuguese were notorious in their conversion efforts and repression of local religions and customs, and their efforts to control Śrī Lankā were no exception making them extremely unpopular with all people on the island, Tamil and Sinhalese alike. The Sinhalese kingdom of Kandy was the first to rebel and allied themselves with Jaffna and the other powers in Śrī Lankā at the time, outside of Kotte which was a Portuguese client state. The Dutch allied themselves with Kandy in 1638 and eventually expelled the Portuguese from their stronghold in Colombo in 1656, betraying Kandy and finally the Portuguese were expelled from Ceylon in 1658.\n\nThe Portuguese ethnic policy was one fierce suppression. Ethnic and religious pluralism had no place for the Portuguese. All powerful or even administrative positions in \nPortuguese Ceylon were held by Roman Catholics. The Portuguese were indiscriminately iconoclastic, destroying Buddhist and Hindu holy sites alike and putting devotees, monks, and clerics of all sects to the sword. In addition, social aspects that the Portuguese found distasteful were removed but the ones they found helpful, such as caste, were increased. This lead to a sharper marker between the Sinhalese and Tamils.\n\nIn any case, the Dutch took control over the North and South of Śrī Lankā and quickly established a treaty with the Kandyans to limit tensions and establish an economic presence with Kandy. Dutch ethic policy was similar to Portuguese, but more established and evolved. While corruption was greater in Dutch Ceylon, with wealthy Dutch stealing land, the overall structure of the government was somehow more functional. Religious policy was somewhat more subdued than the Portuguese and while the Dutch were hostile to non-Calvinist Christianity (they persecuted the Roman Christians) they weren't as fervent about it allowing Hindu Tamils to own land and did not go out of their way to destroy temples. Indeed their hostility toward Catholicism hampered their own missionary efforts and turned many back to Buddhism and Hinduism, though their persecution of the Muslim population was hardly better than the Portuguese. Notably, the Dutch used a different law code for the Sinhalese, Tamils, and Moors, though they used their own for the Sinhalese."
]
}
|
[] |
[] |
[
[]
] |
||
a7g1qn
|
how does constantly pressurized compressed air not build up too much pressure and cause a pipe or hose to burst when a valve is closed?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/a7g1qn/eli5_how_does_constantly_pressurized_compressed/
|
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"I would think in most applications it is pressurized to a certain level that the containment vessel is capable of handling, not simply continuously increasing in pressure indefinitely, since that certainly can rupture the vessel. ",
"The pressure doesn't keep increasing. It's pressurized to a certain level and stays there. Just as a balloon can *hold* pressure for days without the pressure increasing and bursting it.\n\n*Edit:* Or how a heavy book on a shelf doesn't press harder and harder until it breaks the shelf. The pressure has stabilized."
]
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|
[] |
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[],
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||
3f224p
|
why are our spinal cords so poorly protected?
|
Our key organs have evolved to provide adequate protection: the skull around brain, the rib cage around various organs. The spinal cord however seems to be poorly protected, it's relatively exposed and damaging the spine seems common. Can somebody explain the benefit of the spine's position and why it has evolved so?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3f224p/eli5_why_are_our_spinal_cords_so_poorly_protected/
|
{
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"Most of your organs (nearly all of which are as utterly necessary for life as your spine) aren't protected by any bones at all (most of your GI tract for example). \n\nThe spinal cord is actually a very key development in evolution and is conserved across a huge swath of animals (the phylum chordata). The spine's position helps it do all sorts of things, from allowing the more rapid processing of certain signals and helping to manage the feedback loops that control the responses of the sympathetic and parasympathetic nervous system. "
]
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|
[] |
[] |
[
[]
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|
60vx82
|
a law was passed a while back that grants corporations the rights of people
|
In what ways would a corporation NEED to be treated as a person? The only articles I can find seem to be heavily polarized one way or the other.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/60vx82/eli5_a_law_was_passed_a_while_back_that_grants/
|
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"The supreme court of the US decision in Citizens United was that corporations have the same \"free speech\" rights as persons. That means that the Government can't make McDonalds say \"You will get fat if you eat this food\". The CU organization made a movie, and the Federal Election Commission said that their movie was illegal political speech by a company. They sued, and won, to assure that companies can say whatever they want, just like individuals. It was a very controversial decision.",
"This is not true. I understand why you are asking, because many news outlets report it as true, but it is just false.\n\nCorporate personhood is the term and it has been around for over 100 years. It means that the people that make up a corporation have the many of the same rights as every other citizen. They can enter into contracts, they can be sued and they can sue people, and 1000's of other legal components. \n\nIt is a very necessary legal structure that cannot be removed. I mean literally you could not get rid of it without rewriting the vast majority of our laws. And again, it is not new, there was just a prominent court case that pushed it into the public knowledge.",
"Free speech, when it comes to political activities and spending. You can take a look at [Buckley v Valeo](_URL_0_) and [Citizens United](_URL_1_) if you're interested. \n\nCit U:\n\n > In December 2007 Citizens United filed a complaint in the U.S. District Court for the District of Columbia challenging the constitutionality of several statutory provisions governing \"electioneering communications\".[11] It asked the court to declare that the corporate and union funding restrictions were unconstitutional both on its face and as applied to Hillary: The Movie, and to enjoin the Federal Election Commission from enforcing its regulations. Citizens United also argued that the Commission's disclosure and disclaimer requirements were unconstitutional as applied to the movie pursuant to the Supreme Court decision in Federal Election Commission v. Wisconsin Right to Life, Inc.. It also sought to enjoin the funding, disclosure, and disclaimer requirements as applied to Citizens United’s intended ads for the movie.\n\n---\n\nBuckley v Valeo\n\n > Buckley v. Valeo, 424 US 1 (1976) is a US constitutional law Supreme Court case on campaign finance. A majority of judges held that limits on election spending in the Federal Election Campaign Act of 1971 §608 are unconstitutional. The majority, in a per curiam opinion, contended that expenditure limits contravene the First Amendment provision on freedom of speech because spending money, in the Court's view, is the same as written or verbal expression. It limited disclosure provisions and limited the Federal Election Commission's power. The lead dissenting judgment of Justice Byron White contended that Congress's judgment had legitimately recognized unlimited election spending \"as a mortal danger against which effective preventive and curative steps must be taken.\"[1]\n\n > Buckley v. Valeo was extended by the US Supreme Court in further cases, including in the five to four decision of First National Bank of Boston v. Bellotti[2] and in Citizens United v. Federal Election Commission in 2010.[3] The latter held that corporations may spend from their general treasuries during elections. In 2014, McCutcheon v. Federal Election Commission held that aggregate limits on political giving by an individual are unconstitutional\n\n",
"The ultra-simple way to look at this is this: if individual people have basic rights (eg, speech, assembly, the right to petition the govt), why shouldn't groups of people? More specifically, groups of individual people organized as non-profit companies have long enjoyed exercising basic rights. Why should groups of people organized in a for-profit structure (or a union) be denied those same basic rights when the US Constitution clearly does not make a distinction regarding who gets to exercise basic rights? \n\nThis was the basic gist of Justice Kennedy's majority opinion in Citizens United (from wikipedia): \n\n > The majority wrote, \"If the First Amendment has any force, it prohibits Congress from fining or jailing citizens, or associations of citizens, for simply engaging in political speech. Justice Kennedy's opinion also noted that because the First Amendment does not distinguish between media and other corporations, the BCRA restrictions improperly allowed Congress to suppress political speech in newspapers, books, television, and blogs.\n\nPeople look at Burwell v Hobby Lobby as an extension of this basic concept eg, if corporations have 1A rights, why stop there? Why not the full deck of rights? (But note that Burwell v Hobby Lobby only pertains to closely held private companies, not Coca Cola or ExxonMobile). Also from wikipedia on the Hobby Lobby case:\n\n > The court found that for-profit corporations could be considered persons under the RFRA. It noted that the HHS treats nonprofit corporations as persons within the meaning of RFRA. The court stated, \"no conceivable definition of the term includes natural persons and nonprofit corporations, but not for-profit corporations.\" Responding to lower court judges' suggestion that the purpose of for-profit corporations \"is simply to make money\", the court said, \"For-profit corporations, with ownership approval, support a wide variety of charitable causes, and it is not at all uncommon for such corporations to further humanitarian and other altruistic objectives.\"\n\nAnd before everybody starts listing off every reason CU v FEC & Burwell v HL is bad, please note that I am just explaining the SCOTUS decision, not passing moral judgement on it. ",
"Corporations have had *some* of the rights of people for centuries...those rights are basically what distinguish a corporation from a business. The right to own property, the right to enter contracts, the right to sue, these have being corporate rights for a long time.\n\nA more recent US Supreme Court ruling, *Citizens United v. Federal Election Commission* 558 U.S. 310 (2010), found that corporations had the right to engage in unlimited political speech, so long as they were not directly contributing to a campaign. This gave rise to the various PACs running \"issue\" ads during the election cycle.\n\nMany people unfamiliar with the details of the and the law in general have crudely characterized this as corporations have the exact same rights as people. ",
" > In what ways would a corporation NEED to be treated as a person?\n\nPeople haven't given you a really good explanation of this, but the reason corporations *need* to be treated as \"legal persons\" is that, otherwise, the legal process just couldn't work. \n\nSay I'm doing advertising work for the Coca-Cola company. I sign a contract with Coca-Cola for their services, which is signed on their end by a vice-president for marketing. Six months later, Coca-Cola fails to pay, and I want to sue them. Well, what if that marketing executive has been fired? What if the entire leadership team is gone? \n\nIf Coca-Cola wasn't a \"legal person,\" I couldn't just sue the company -- I'd have to find the fired VP and sue him personally. Also, there's the fact that literally thousands and thousands of people are ultimate owners of stock in Coca-Cola -- if the Court awards me a judgement, unless I've found and served each of these people they Court wouldn't have jurisdiction over them and they couldn't be compelled to pay me.\n\nCorporate personhood gets around that by creating a legal entity that collects everyone's rights and obligations. Instead of having to figure out how tax liability for Coca-Cola's revenue is apportioned among its thousands of stock owners, the government taxes the company. Instead of having to sign contracts with the thousands and thousands of people who own Coca-Cola, you can sign a contract with the company. If you're poisoned by a bad Coke, you can sue the company without joining each individual employee and owner as a defendant. \n\nSo when we talk about a corporations \"rights,\" what we're really talking about is the *collective* rights of the individuals that own the company, collated into a single legal nexus. When the Supreme Court is saying that corporations have free speech or religion rights, they're saying that the *owners* have such rights and that these rights can be expressed through the corporation in their name.",
"This isn't exactly what the law actually is. \n\nThe propaganda here refers to the Supreme Court decision in the \"Citizens United\" case.\n\nHere's the back story.\n\nWay back in the day, the [Campaign reform act](_URL_0_) was passed. \n\nAmong other things, this limited how corporations could spend money that was related to elections.\nA short time after that, Michael Moore produced and released the film \"Fahrenheit 9/11\", a purely political hit piece on the Bush administration. Conservative groups sued, complaining that this was illegal under the act. Their claim was rejected. \n\nThen a conservative group called Citizens United produced a film called \"Hillary the Movie\". This was a purely political hit piece on the Clinton Campaign. Liberal groups sued, complaining that this was illegal under the act. This claim was granted. Citizens United appealed to the Supreme court, and prevailed. \n\nWhat citizens united really says is that just because you pool your money into a 'corporation', you don't lose the right to speak. \n\nThis is, ironically, MORE FAIR than the prior system... Here's why:\n\nIf I'm Bill Gates, I can spend my own money in vast sums to do whatever I want in either system.\n\nBut if I'm Joe Schmoe, I don't have much money... But If I have a million friends that agree with me and we pool our money together, why can't that collective spend it to do the same as Bill Gates can?\n\nThe rich will always have access to power in government. Maybe that's not right, but do you really think that Bill Gates could not get an audience with the President, regardless of how he spent his money?\n\nAllowing others to pool their money to have that same reach is the only really fair solution to an unfair problem.\n\nNow, some people say it means money=speech... Perhaps. But again, that's just reality. If you have the money you can broadcast your speech much more widely. Again, it may not be fair, but the other option is giving the government unlimited power to restrict any speech that it deems political, and that's very dangerous.\n\nThe ability to say not nice things about those in power is the heart and soul of the idea of freedom of speech. And to attack that right is very very dangerous."
]
}
|
[] |
[] |
[
[],
[],
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"https://en.wikipedia.org/wiki/Buckley_v._Valeo",
"https://en.wikipedia.org/wiki/Citizens_United_v._FEC"
],
[],
[],
[],
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"https://en.wikipedia.org/wiki/Bipartisan_Campaign_Reform_Act"
]
] |
|
1c6r9v
|
How does degreaser (soap, purple power, engine stuff) degrease?
|
Is there a difference between engine grease and kitchen grease that degreasers can tell? What physically makes them break up grease? What makes some degreasers work better than others?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1c6r9v/how_does_degreaser_soap_purple_power_engine_stuff/
|
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"Q: How does degreaser (soap, purple power, engine stuff) degrease? \nA: They emulsify the grease. That means they allow it to mix with water which wouldn't usually happen due to molecular polarity.\n\nQ: Is there a difference between engine grease and kitchen grease that degreasers can tell?\nA: They are different hydrocarbon molecules, but they are all non-polar molecules.\n\nQ: What physically makes them break up grease?\nA: _URL_0_\n\nQ: What makes some degreasers work better than others?\nA: Mainly concentration. If dish soap was full strength it would dry your hands even worse.",
"Put simply, water and oil don't mix. You get a molecule where half of it will mix with water, and the other half will mix with oil. When you apply soap to something, it sticks to the oil. Then when you rinse, it also attaches to the water and washes away. ",
"You have an oil/grease (non-polar) and water (polar) which cannot mix, therefore the water will not wash the grease away. Think of your detergent as an adapter molecule from non-polar to polar.\n\nOne end of a detergent will be non-polar that will interact with the oil, the other end will be polar/ionic that will interact with the water. This way, the detergent \"sticks\" to both the oil and the water, which brings the oil into the water so that it can be washed away. If it helps to think of double sided tape, that's more or less what's happening with the molecules.\n\nLook at [SDS](_URL_0_) for example, you can see that the molecule has a long, nonpolar, hydrocarbon chain and a charge sulfate group at one end. The hydrocarbon sticks to the oil and forms a polar shell around it that allows it to enter solution. Some work better than others depending on concentration and how polar the polar end is. In biochemistry, SDS is very harsh and can denature proteins (which have a non-polar core) where Triton X is softer and won't get into the protein to denature it."
]
}
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[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Emulsion"
],
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"http://en.wikipedia.org/wiki/Sodium_dodecyl_sulfate"
]
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|
9swori
|
how come we are often more energized when we're running on only a few hours of sleep, compared to days when we had a full 7-8 hours of sleep?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9swori/eli5_how_come_we_are_often_more_energized_when/
|
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"Sleep for humans is made up of 5 different 'types' or 'stages' divided into two categories, which we cycle through. This progression is Non-REM 1, 2, 3, 4, 3, 2, then REM, after which we will either go back to Non-REM 2 and repeat from there, or wake up at least slightly and fall back asleep into Non-REM 1. Each stage involves different physical processes in the brain and the rest of the body and each has a different 'intensity'. During Non-REM 1, you're still largely awake, but your brain is starting to wind down -- this is the period where you might still be reading your book or talking to your partner but you won't remember it in the morning and won't make much sense. Non-REM 2 is 'soft' or 'light' sleep where you're unconscious but can be easily woken and are likely to toss and turn. Non-REM 3 and 4 are 'deeper' sleeps where the body temperature drops and the body becomes like dead weight. Then comes the REM stage, when we dream and undergo the most intense neurological refreshes. It tends to be hardest to wake us up from this stage. As the night goes on, each REM cycle tends to (but doesn't *necessarily*) last longer than the last (that's one reason you can't just take a 100 minute nap every few hours in lieu of a full night's sleep).\n\nIf you wake up naturally, you will almost always wake up when an REM cycle is over. The processes our body uses to maintain a consistent temperature slow and stop during Non-REM 3, 4 and REM stages, so we get colder. When REM ends and we wind up in Non-REM 1 or 2, they resume, and our temperature rises again; combined with the return to lighter sleep levels, the physical change tends to be what 'naturally' wakes us up. And waking up during Non-REM 1 or 2 tends to feel fine.\n\nThere are two big primary things sleep does for our brains, according to the research we've been able to do (it's a hard area to study). During the deeper phases of sleep our brain slows down a lot of processes so that it can essentially 'flush out' waste chemical products and secrete things that the hard-working conscious brain burns through too quickly to replenish (eg glycogen). \n\nWhen you have an alarm that always goes off at exactly 7:00 AM, there's a good chance it'll hit you smack in the middle of a Non-REM 4 or REM stage, when the brain has put itself into that low-power mode to give itself a clean. You can't just snap it right into action, it takes a while to bring your metabolic processes back up. Until it does so you'll feel disoriented, slow, foggy. That feeling can potentially last throughout the day depending on a variety of circumstances we don't fully understand yet. Entering and exiting these phases involves different chemical triggers, and the problem seems to be the end of REM being triggered by the progress of waste-eliminating or glycogen-secreting processes. If you enter REM and then awake before these processes have made much progress, your brain doesn't seem to be able to completely restore the metabolism to normal levels.\n\nSleep is something difficult to *precisely* study because it's not as if we can just cut into someone's brain in the middle of the night and quickly get a good look at the chemical processes happening in different places at the same time. Nor we can we really rely on animals as great comparisons in this area. The human brain is the most complex thing in the world and it does so many overlapping things. It's much harder to figure out than something like the kidney."
]
}
|
[] |
[] |
[
[]
] |
||
1hfxi7
|
texas hold'em
|
I know the rules, I want to know strategy. Betting patterns, does everyone have a tell? How do I spot it?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1hfxi7/texas_holdem/
|
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"This isn't really an ELI5 question because the answer(s) are entirely too broad. There are 100s of entire books written on poker strategies, especially more so in recent years as poker and WSOP tournaments have risen in popularity.",
"As machinedhead933 stated this question is way to broad for an ELI5 but I will give some minor tips that hopefully point you in the right direction.\n\nThere are four styles of play based on hands and betting patterns.\n\nHands include loose and tight, betting patterns include aggressive and passive.\n\nA person who is playing tight passive will only play when they have good hole hands AA for example or suited AK. That player will then bet very passively, for example just betting the minimum bet or checking and only calling. This is an attempt to persuade your opponent that he/she got a better hand than you and they will continue to push into you.\nLoose aggressive is someone who will play with not so good hands like 77 or A5 suited and bet aggressively by raising, betting higher than minimum bet, not checking. The idea behind this strategy is to convince your opponent that you have the nuts (best possible hand) so that they fold out even if they could have beaten you.\n\nGenerally speaking the better style of play is tight aggressive - you will see less bad beats and its harder to make a mistake, and the worst style of play is loose passive - you will be in hands you have no means to be in and you are not convincing anyone that you have a good hand.\n\nHowever the best strategy is to be like the chameleon and change your play style as you see fit. Do you have the most chips on the table? Maybe you should play loose aggressive to push other players in submission. Are you short stack, maybe you should play tight passive to protect your chips and wait for that sweet all in call when you got the nuts.\nIs the guy next to you being brashly aggressive, play a tight aggressive hand and see him fall into his own trap.\n\nAs said before there is a lot more to it, like pot odds and card counting that is way beyond the scope of a simple ELI5, but if you google search Texas Holden strategies there is definitely a plethora of good websites out there. And then of course the best way to get good at Texas hold'em or any kinda poker game like Omaha hi lo or seven card stud is to practice practice practice."
]
}
|
[] |
[] |
[
[],
[]
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|
7fe5xz
|
What is the body's conversion efficiency of energy stored in food to energy stored in fat, or energy available to do work with?
|
For example, if I eat 1000 calories of sugar:
* How many calories will be stored in fat (assuming none of the calories are used for exercise etc).
* How many calories are available to perform work with (after the body has converted the sugar to ATP, etc). The assumption is that the conversion process from Sugar -- > X -- > ATP -- > ? is not 100% efficient.
* How do the above numbers differ for different sources of energy. For example does eating 1000 cal of fat result in the same number of calories available for work as eating 1000 cal of sugar?
Bonus question:
* How efficient is the body in converting the energy stored in fat to energy available for work (e.g. ATP)
**Note**: I am not a biologist, from my understanding ATP is the last form of energy muscles use, albeit I could be wrong.
|
askscience
|
https://www.reddit.com/r/askscience/comments/7fe5xz/what_is_the_bodys_conversion_efficiency_of_energy/
|
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"Hello friend, when consuming calories from any source (protein fat or carbs) the body will undergo specific pathways depending on your current state (fed fasting or starving) these pathways convert the calorie sources you consume into several intermediates which can then be stored (glycogen, TAGs) or used immediately (glucose, ketone bodies, etc) to produce ATP. Eating pure sugar would generally be broken down to glucose and then stored as glycogen or used to generate ATP depending on your metabolic needs. The pathways that take place are sometimes very efficient (Krebs cycle) and sometimes can be less efficient like the Electron transport chain (where the most ATP is produced) which will lose around 50 of a vital step (H+ gradient) as heat instead of generating ATP. \n\nVery simply put calories are calories since your body can convert or store carbs, protein, and lipids into interchangeable intermediates. That is a very basic and generalised explanation. Hope this helps, sorry for typos I'm on mobile!\n\nSource: Medical student. ",
"Well, as far as the processing, storage and other ‘taking in’ goes, you’re looking for the thermic effect of food. That is energy used to convert it from its raw state to one that’s ‘ready to burn’.\n\nCarbs have a 5-15% thermic effect, depending on complexity. Very complex carbs take more energy to process than simple ones.\n\nFats have at most 5-15%, some sources claim well below 5%, and are seen as the most efficient.\n\nProtein is much harder to digest and process, with a thermic effect of 20-35%, depending on complexity and blend.\n\nSo the conclusion here is that replacing fat or sugar calories with an equal amount of protein calories will reduce your net caloric intake after cost of processing. It isn’t a huge number but is meaningful over time - I ran some numbers for a long post a while ago, and it could be enough for a few pounds of weight gain or loss a year. ",
" > For example, if I eat 1000 calories of sugar:\nHow many calories will be stored in fat (assuming none of the calories are used for exercise etc).\n\nIf you fulfill all other caloric requirement before you eat that 1000 calories, it's pretty much 1000. Your body is already converting one chemical into another all the time, so this is not really a notable extra expenditure.\n\n > For example does eating 1000 cal of fat result in the same number of calories available for work as eating 1000 cal of sugar?\n\nYes, because we adjusted the food-caloric value of fat and sugar so that they do. the conversion factors are called ~~Atkins~~Atwater Numbers, and they're basically used to convert weights of nutrients into caloric values. \n\n",
"I don't know the rate for storage, but for expenditure the maximum your body can produce is 31.5 +/- 2 calories (290kJ/kg) for every pound of body fat you have *per day*. That level will only occur during a state of hypophagia. Hypophagia is when you are using way more calories than you are consuming, so think fasting or exercise without using it as an excuse to eat :p.\n\n_URL_0_\n\nEdit: autocorrect typo\n\nEdit: added per day since that was apparently very confusing",
"In addition to what others have said with respect to the thermic effects of food (which answers your third bullet), the proportion of calories eaten that are burned/used for various processes vs stored is in constant flux. Proportions would be based on tons of factors including things like circulating levels of hormones such as insulin (promotes storage I.e, anabolic) and glucagon (opposite effect I.e., catabolic). I don't think you could ever put exact numbers on it. However the body is VERY efficient at 'using' (either burning or storing) calories from food. Only a very small amount of the energy taken in is 'lost' in the form of heat, which helps us stay warm blooded. Look up mitochondrial uncoupling for more on that.\n\n\nSource: BSc biochem, BSc health science, MSc health science focusing on obesity",
"The Atwater system is what we use for rough estimates for the available energy in food--metabolizable energy. The pure energy stored in food, the gross combustible energy, does not equal metabolizable energy 1:1 for the following reasons:\n\n1. Food must be broken down into monomeric components to be directly absorbed (the majority of this absorption occurs in the duodenum, the first section of the small intestine) and this breakdown process is reliant on enzymes. Enzyme action is in turn reliant on available substrate surface area and time. Time for enzymatic action on the food you eat is controlled by gut motility. If you don't eat regularly your body will slow gut motility and this has the effect of increasing how much you absorb from your food. Anything that decreases gut motility will increase the metabolizable energy of food. \n\nSurface area is controlled by the physical properties of the food itself, the mechanical mixing due to GI tract muscular contractions, and in the case of fat--bile salts that act to increase surface area of fat droplets by breaking them into much smaller droplets (micelles) that don't recondense in the aqueous chyme. Insoluble fiber plays a role in reducing available surface area for amylase (the enzyme that breaks starch down into simple sugars), so high fiber foods have decreased metabolizable energy. But we'll come back to fiber because it is tricky.\n\n2. Monomers (amino acids, monosaccharides, and fatty acids) must be absorbed by gut epithelial cells and transported to the portal venous system. From there they go to the liver and then see systemic distribution from the liver. These transport systems require energy and some monomers required less energy than others to shuffle around. Some macronutrients yield less metabolizable energy than others due to higher energy investment for transport and uptake. Some people can't absorb certain monomers like fructose very efficiently. Also, new research is showing evidence that stimulation of sweet taste receptors leads to increased absorption of nutrients in the SI, meaning that some foods like sugar and sugar substitutes may boost the metabolizable energy of others.\n\nFurther, uptake of macronutrients by tissues is often the subject of regulation. People with severe peripheral insulin resistance see little to no metabolizable energy from glucose because it never enters those cells to be used. Different tissue types have different macronutrient preferences and adjust absorption and subsequent catabolism accordingly. \n\n3. Macronutrients are catabolized in cells to power ATP generation. There are a number of different pathways and not all have the same ATP yields. The catabolic pathways that require oxygen occur in the mitochondria, which means that mitochondrial density and efficiency affect the metabolizable energy of food as well. People who are physically active have greater mitochondrial density in their skeletal muscle fibers and there are studies showing that things like fasting increase mitochondrial efficiency--resulting in increased ATP generation.\n\nI know your question is more asking about bookeeping but unfortunately bookkeeping is a nightmare, is variable across the population and is even variable in one individual depending on their activity level and things like, weirdly--the bacteria in their colon. I mentioned fiber before and how it is tricky. The Atwater system's largest flaw is its accounting for fiber.\n\nFiber and whatever monomers manage to escape the small intestine end up in the large intestine, which is full of bacteria. Gut bacteria digest the remaining di and monosaccharides (if you're lactose intolerant, this is where the lactose is broken down) and secrete out short chain fatty acids which is another source of energy for us. Gut bacteria can also partially digest fiber, as well as certain oligosaccharides found in vegetables/fruit, and non-nutritive sweeteners like stevia (not aspartame, aspartame is essentially an amino acid pair that gets absorbed up in the SI). \n\nBecause the metabolizable energy is effectively second-hand, there isn't much by way of hard numbers but animal and human studies support the idea that gut bacteria play a big role in obesity and the theory behind this is that some people have more efficient gut bacteria than others, seeing increased metabolizable energy from food sources.",
"Here's one way to do it: Humans burn 100 watts in food energy - you get this by assuming 2200 kcal diet and convert to joules by multiplying by 4.19e3 J/kcal and divide by seconds in a day.\n\nA laborer can produce [75 watts of work over an 8 hour shift](_URL_0_). \n\nSo the 'useful work efficiency' of a human, treating them as a machine, is \n\nOutput/Input = (75 W x 8 hrs)/ (100 W x 24 hrs) = 25% \n\nSurprisingly efficient, I'd say. About the same as an internal combustion engine. It's probably a bit lower in reality, because this laborer is probably consuming more than 2200 kcal. If you assume 3500 kcal/day, it becomes 14%. "
]
}
|
[] |
[] |
[
[],
[],
[],
[
"https://www.ncbi.nlm.nih.gov/pubmed/15615615"
],
[],
[],
[
"https://en.wikipedia.org/wiki/Human_power"
]
] |
|
8nr4wn
|
Why are absolute rulers now called dictators instead of monarchs?
|
Dictators seem just like a monarchy, usually their eldest son inherits the country and so on. And they have the powers of monarchs back before they were all destroyed.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/8nr4wn/why_are_absolute_rulers_now_called_dictators/
|
{
"a_id": [
"e004hvr"
],
"score": [
2
],
"text": [
"I suppose the primary difference between a monarchy and a dictatorship is in terms of self-identification. We still have absolute rulers being monarchs, mind you. KSA and Qatar, amongst other Gulf states, still have very strong monarchies. What differentiates a monarchy from a dictatorship is self-identification. A dictatorship becomes a monarchy when the ruler drops all pretense of democratic rule and says \"Yep, I'm the king now\". \n\nI assume you're thinking of North Korea? Hereditary succession isn't as common in modern dictatorships as you might think. Most modern dictatorships transfer power simply within the ruling party, not within the family, as it does in the DPRK. Think the Soviets with Stalin > Krushchev > Brezhnev. Also, monarchies are not necessarily passed on based on primogeniture. Most European kingdoms started out as elective monarchies; the nobles would choose a king from amongst them, best exemplified in Hungary, Poland-Lithuanian Commonwealth, and the Holy Roman Empire, and it was only later that primogeniture became the norm. Even the most classic examples of primogeniture, France and England, began as elective monarchies, although this quickly changed once each state managed to produce stable dynasties. Hell, technically the Vatican City is a monarchy; the Pope rules, and is absolute \"Sovereign\" over the Vatican City, and he's certainly elected. They are still monarchies, ruled by a king/duke/emperor, just that the monarch's title isn't hereditary. What this intends to show is that the definition of a monarchy isn't based on hereditary succession. So why isn't a dictatorship a monarchy? Primarily, a dictatorship will still maintain pretenses of democracy. North Korea still has a parliament (note: not incompatible with monarchy), its rulers are still nominally elected, and the Kims are just the leader of the largest and permanently installed party. Regardless of whether or not they are de facto dynastic rulers, they remain dictators until they choose to become kings.\n\nThis isn't a new concept, mind you. There are plenty of historical examples of what we would recognise as dynastic dictatorships without being monarchies. The de Medici family, for example, maintained de facto dictatorship (bar a few revolutions) of the Republic of Florence for almost a century before actually establishing the Duchy of Florence, thus making themselves dukes (i.e. monarchs). Then there's also the classical example of Rome; Rome's dictatorship was established by Julius Caesar, but he was not a monarch. It was only once his \"son\" Augustus established himself as emperor and dissolved the Republic (but not all its apparatus) that Rome transitioned to a proper monarchy. \n\nI suppose technically there's no difference in terms of powers between a monarch and a dictator. However, the distinction between a dictatorship and a monarchy isn't anything new; it's always been there, as far as there have been democracies and monarchies to make the distinction relevant, and is certainly not a modern invention. The transition from a dictatorship to a monarchy has always historically been the dissolution of the vestiges of democracy, and formalisation of true monarchical status, neither of which has really happened in North Korea, or any other modern dictatorship, for that matter,."
]
}
|
[] |
[] |
[
[]
] |
|
29zjnb
|
As a car sits outside, does the temperature inside the car just keep going up, or is there an upper limit?
|
askscience
|
http://www.reddit.com/r/askscience/comments/29zjnb/as_a_car_sits_outside_does_the_temperature_inside/
|
{
"a_id": [
"ciq4hvm"
],
"score": [
11
],
"text": [
"Car absorbs thermal energy from sunlight, but also radiates it back via [black body radiation](_URL_1_), and tranfer it throught [air convection](_URL_0_), etc. when equilibrium of those forces (not limited to what i mentioned)is achieved the body of a car will maintain constant temperature. Hope it helps."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Convective_heat_transfer",
"http://en.wikipedia.org/wiki/Black-body_radiation"
]
] |
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