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fpoe90
|
why does microwaving continuously for sixty seconds heat food so much more effectively than two consecutive thirty-second cycles?
|
I noticed that my tea tends to be much hotter when I microwave it continuously than when I take it out half-way through. This result seems to be consistent regardless of material. Even if I open the microwave just for a quick second, whatever I’m microwaving needs significantly more time to heat. Why is this?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/fpoe90/eli5_why_does_microwaving_continuously_for_sixty/
|
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"Because if you're using thirty-second intervals, during the intervals heat escapes. If you keep it in for the full sixty seconds, no heat escapes. :) hope this helps\n\n & #x200B;\n\nAlso there's nothing wrong with microwaving tea imo",
"The heating element in your microwave takes up to ten seconds to get to full power, and you'll want to leave the door closed for a few seconds after it beeps to give the element time to cool down and stop sending radiation everywhere.\n\nAlso, microwaves typically have hot spots and cold spots, and if your drink doesn't stumble into a hot spot, while the heating element is hot, during its time in the box, it will be much colder because it absorbed less energy.",
"Microwaves work by agitating water molecules (heat after all is just agitated molecules). However, not all water molecules are agitated at the same time - as the waves don't blanket the entire inside the entire time. \n\nSo, think of your glass of water as bunch of swings. You are the microwave. As you push a seat it starts to swing, then you run to the next one and push it, then the next. But, as you get away from the first one, it starts to slow down a bit. Now, if you add in a short break at the end, that first swing will slow down even more. To add to this, imagine you can only push the swing a little bit each time - if you can get back to the first swing while it's still moving, your push will make it go faster each time you get to it. \n\nThe swings in this case are the water molecules - and by stopping the microwave, you're giving a chance for them to slow down a bit. \n\nPro-tip: Most microwaves have a \"Power Level\" button where you can set the microwave to 40% to 100%. This doesn't actually change how powerful the microwave is - it shuts the heating element off for 60% of the time to 0% (roughly). So, if you've ever tried to make nachos in the microwave and found it doesn't melt the cheese evenly - try setting it to 50% and doubling the time.",
"The magnetron inside your microwave that generates the microwaves is a vacuum tube, and the cathode inside it has to warm up before it starts emitting electrons. (literally warm up, as in temperature) \n\nYou will usually be able to hear a difference in the noise it makes a few seconds after you start it, this is when it's really starting to work.",
"Takes time to heat up, like everything else. Try making two bags of microwave popcorn right in a row. The second bag cooks like, 30 seconds faster than the first.",
"Because it takes like 4 seconds or so for a microwave to get fully going. So your 60 seconds is actually 56 seconds of heating and your 2-30 seconds is 52 seconds.",
"Think about it this way...\n\nWhy does driving in a straight line at top speed get me there faster than driving halfway, stopping, and going the rest of the way?\n\nThe microwave takes a bit to get up to full speed/power if you will that's why you see a difference.",
"The heating system in your microwave has to warm up and takes a few seconds to get to max heat, so microwaving continuously for 60 seconds would blast more radiation than two separate periods. \n\nThis is similar to how driving an old car at max speed for 60 seconds would go farther than in two 30-second drives, because the car will take some time to accelerate",
"Microwaved tea is an affront and abomination, please stop it immediately and invest in a kettle like Sheldon. Source am English"
]
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1s43xk
|
when i eat am i actually chewing as loud as it sounds like to me?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1s43xk/when_i_eat_am_i_actually_chewing_as_loud_as_it/
|
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"No, when you chew, vibrations travel through your jaw bone and directly to your inner ear, where you hear them. On the other hand, the vibrations have to travel through air to get to someone else's ear.\n\nSound travels best in solids, followed by liquids, and worst in gasses. This is because molecules are closer together in denser materials which allows for better transference. "
]
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[] |
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57e6j6
|
how are the body's major structures genetically coded?
|
Currently in my first year of college biology, and genes were described as a string of nucleotides which codes for a specific protein. Do they do more than this? What genetic system controls how tall you are or why you have a femur?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/57e6j6/eli5_how_are_the_bodys_major_structures/
|
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"The simplistic way of looking at genetics is that one gene codes for one protein, but this is not always the case.\n\nThink of embryology (the development of an organism) like the feudal system--middles ages. You have kings which control lords, lords that control knights, knights that control soldiers, etc. (I'm probably butchering history.)\n\nI chose the middle ages because the components (knight, whatever) are sort of \"boss\" within their own dominion.\n\nThe king controls the country, the lord controls one small bit of that country, etc., but together, each hierarchical layer results in the overall structure and organization of the kingdom. Same with organisms.\n\nThe gross body plan (where do I form the head, the arms, the legs) is controlled by a group of transcription factors called [homeobox genes](_URL_0_). The expression of these genes outlines the \"kingdoms\" of the head, arms, legs, torso, etc.\n\nTranscrption factors, like kings, lords, and knoghts, are the \"boss.\" They tell other genes what to do by controlling when and where (spatially:from the very broad, head, arms, legs, to the very specific, rod photoreceptors of the retina) they turn on.\n\nBecause homeobox transcription factors are the king, the \"big boss,\" if you mess up their expression (tell them to turn on where or when they aren't supposed to) you get a mess. \n\nIn ants, scientists have turned on leg homeobox genes on where antenna were supposed to form and these ants get legs growing out of their head. Bad things.\n\nThese homeobox genes controll arms, legs, head, but get more specific or small too like retina in the eye, fingers. These genes map the body and controll the genes that make sure your femur forms in the right place. \n\nAs with the Middle Ages (perhaps I'm being unfair) footsoldiers are interchangeable/replaceable. The same footsoldier genes which make the bone of the eye socket and toes make the bone of the femur. It is the \"bosses,\" the homeobox \"kings\" and their underling lords/knights transcription factors which ensure that the femur is a femur and found in your leg and your phalanges (some toe bones) are toe bones and found in your toes.\n\nSo we just showed that gene expression isn't a binary: the how much, the where, and the when can be controlled by transcription factors. It turns out that particular traits (a phenotype) aren't always caused by a binary on/off of one gene like you may have learned is true of Gregor Mendel's pea plants in school.\n\nTraits can be the composite effect of many different genes.--and these genes' interactions with the environment. Height, skin color, intelligence are all examples of such traits.\n\nIf we simplify it, it makes sense that genes that control things like the density of bones (how much gravity pulls on them, whether they can support one's weight), connective tissue properties, nutrition (starvation--an environmental effect--in childhood stunts growth), as well as hormone changes and genes that more directly control bone length (human growth hormone is an obvious example) all work together to result in final height."
]
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3fvov2
|
How were German embassies treated in the allied countries during WWII?
|
Also, what kind of tasks were required of them during the war from both the host country and the origin country?
edit1: Ok cool, so the staff either left or were detained before being traded.
edit2: What happened to the embassy buildings themselves? Once we were at peace with Germany, did the (new?) ambassadors get to go back to the same buildings? Was anyone afraid that we've planted bugs inside the buildings while they were unoccupied?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/3fvov2/how_were_german_embassies_treated_in_the_allied/
|
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"Ambassadors from enemy powers are handed their papers and sent packing as soon as war starts, and WWII was no different in this regard. Such very, very scanty contacts as did take place between Germany and its enemies took place informally between diplomats to neutral countries, e.g. Switzerland for Hitler's \"peace\" offer in 1940 or Turkey in 1943 (IIRC -- possible 1944) when Himmler tried to sell the lives of Jewish civilians.",
"German embassies in countries of the Allied Powers (UK, France, US or the USSR) were closed down as soon as Germany declared officially war on these or otherwise. One week before invading Poland the German embassy in London and France advised all German residents in these countries to leave. After the British ultimatum expired on September 3rd, these two embassies were closed down on September 4th. The German ambassador (or Chargé d'Affaires) in London (Dr. Kordt) and in Paris (Johannes Graf von Welczeck) left on the same day. [Here is a picture of Dr. Kordt](_URL_0_) leaving the German embassy on September 4th (bottom right). Graf von Walczek was not permitted to cross into Germany until the French ambassador to Germany arrived safe in Belgium. The Swiss embassy in London and Paris took over some tasks.\n\nSame goes for the German embassy in Moscow. Before Graf von Schulenburg delivered \"a memorandum\" to Molotov on June 22nd 1941, he destroyed all records and documents in the German embassy. After the meet up he was detained and the embassy staff was arrested. They were later transported to the Turkish border and set free.\n\nThe German embassy in the US was closed down right after Pearl Harbor. Staff was set under house arrest. Later they were transferred and detained in various resorts. From the [History of the Bureau of Diplomatic Security - Chapter 2 - Diplomatic Detentions during Wartime](_URL_1_) (PDF warning):\n\n > After Pearl Harbor, U.S. officials initially allowed Axis diplomats to stay in their homes and have unrestrained access to the Swiss Legation, but later transferred them to resorts in the Appalachian Mountains until the Department of State could arrange for an exchange of diplomats between the United States and the Axis powers. The Germans had transferred U.S. diplomats to a hotel at Bad Nauheim, yet, reports of Japan’s less than hospitable treatment of U.S. diplomats soon reached the Department. Although “his patience was sorely tried,” Secretary Cordell Hull declared that he would not “be drawn into a contest in which he would have to out stink a skunk;” and “there was a limit below which the United States Government would not stoop” in its treatment of enemy diplomats.",
"edit2: To be pedantic, the people are the \"embassy\"; the building is the \"chancery\". But [metonymy](_URL_0_) has long since had its way with the language.\n\nThe [Vienna Convention on Diplomatic Relations](_URL_2_) of 1961, article 45, is the current rule, but I believe this codifies older practice. \"Sending state\" refers to the ones who sent the embassy; \"receiving state\" is where they went.\n\nThe receiving state must respect the premises of the diplomatic mission. The sending state may give custody of its chancery to a third party acceptable to the receiving state. But [G. R. Berridge, Embassies in Armed Conflict, p 23](_URL_1_) says that the protection in practice is only for the same reasonable short time as for the embassy going home. It's not clear from that whether a third-party protection could continue past that time.\n",
"I know, Ireland was neutral in the war, but considering our neighbours, and all, you might be interested in this, for what it's worth.\n\nIn Ireland there was a lot of controversy near the end of the war when our Taoiseach, Éamon de Valera, offered his condolences to the German Ambassador over the death of Hitler. This damaged Ireland's relationship with the Allies, and in Churchill's VE day speech he criticized Ireland's neutrality, which lead to [this](_URL_0_) response from De Valera a few days later."
]
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"http://legal.un.org/ilc/texts/instruments/english/conventions/9_1_1961.pdf"
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9b0bi1
|
how do relatively young people afford to live abroad for an entire year?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9b0bi1/eli5_how_do_relatively_young_people_afford_to/
|
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"They do not pay for it themselves. In situations like you’ve described it’s generally 1) Mom and Dad, 2) academic scholarships, or 3) employer sponsorships.",
"Do you mean during uni? Loans and savings and planning and govt or organisational help (like funded scholarships or Erasmus). When you're still at uni there's lots of help available.\n\nAfter uni? Savings and planning mostly. It doesn't have to be that expensive if you are able to adapt and change your habits and expectations, and there are a thousand ways to travel and live abroad. It might indeed mean postponing building a career or quitting a job, but that's an individual choice. ",
"Most countries are much more affordable to live in than Canada and the US. So essentially, you need to have $10,000 in savings before traveling so you've got money for your plane tickets and a bit of a buffer, and then you work as you go to keep yourself funded, and come back when the money runs out.\n\nI know a lot of people from Australia who came to North America out of university, worked in tourism to make enough to live on, partied at night, and then went home to find a real job and start saving for retirement.\n\nSome people take out loans, some people have rich families, some people sell some of their stuff (car, etc.). Others work menial jobs for a year after school before they go.\n\nIt's also worth noting that student loans often don't require repayment until you're finished your schooling; so if you graduate locally and then go abroad for more \"schooling\", you are holding off loan repayments until you return.\n\nIn all cases, I'd say they're more interested in gaining experience than they are in worrying about savings.\n\nAnd the truth is, having work experience in foreign countries on your CV can go a long ways towards getting you hired in better paying jobs. So that trip can be a very good investment.",
"Most Countries are a lot cheaper to live in than the US or Canada (as in 10% or less)\nGet a job working a bar or something to do with English speaking tourists and you are set\n\nYou can’t live like a tourist, You live like a local person \n\nGo to a kibbutz in Israel and they feed you and give you a little spending money in exchange for work\n\nIt’s not hard if you don’t insist in maintaining the same lifestyle you have in Canada\n",
"I spent a year in Australia when I was younger. I worked to save up for the trip and then worked when I was there. I did house removals, building site labouring and fruit-picking.\nI also taught English in Taiwan for a couple of months.\nThere are lots of opportunities in lots of countries to teach English if you're a native speaker.\nMy first time living abroad was in Spain. I saved up £400 and figured if I didn't find a job I'd have enough for a 3-4 week holiday. I found work in a bar after a week and ended up staying for 4 months.\n"
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13g4zc
|
How much water was stored by glaciers during the last glacial maximum?
|
Today, glaciers store about 69% of the earth's fresh water. How much was stored 22,000 years ago?
|
askscience
|
http://www.reddit.com/r/askscience/comments/13g4zc/how_much_water_was_stored_by_glaciers_during_the/
|
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"Thinking about this in terms of percentages is a bit confusing because the total amount of fresh water on earth has changed. During the last glacial maximum, there was a greater total amount of freshwater because more of it is locked up in ice on land and the seas were lower and saltier.\n\nAt the moment the size of the cryosphere is about 32 million cubic kilometers. Based on changes in sea level, the last glacial maximum was estimated to have and additional 52 million cubic kilometers of ice for a total of 84 million cubic kilometers. Source: Lambeck, 2000 ([PDF](_URL_0_))."
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[] |
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afle4j
|
how are some fish able to come back to life after being frozen, and how long can they be frozen for and still come back to life?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/afle4j/eli5_how_are_some_fish_able_to_come_back_to_life/
|
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"It depends on the type of congelation, for example, you can use a fast-frezzer to freeze a fish so the freezing it's only superficial and if you put the fish in water again you wait for a few minutes and voilá, the fish has \"revived\", in change, if you use a normal freezer the fish won't be able to revive cuz a lot of ice cristals have been formed in the interior of the fish and destroyed his vital organs."
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9fcys7
|
what exactly is phage and what do they do?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9fcys7/eli5_what_exactly_is_phage_and_what_do_they_do/
|
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"Phage is a Latin term that means \"to consume\". Bacteriophages for example are viruses which specialize in infecting bacteria (\"phage\" is typically short for bacteriophage). Such viruses are interesting as alternatives to antibiotics as viruses are usually extremely specific in the types of organisms they can infect meaning giving bacteriophage to someone with a bacterial infection can wipe it out without harming the patient or even other non-harmful bacteria such as in their gut.",
"Phages are viruses that attack bacteria. so it's like setting loose a cat in a barn full of mice, the phage is pest control and it doesn't infect big things, like us, only bacteria.",
"Kurtzgesagt have an [excellent video about them](_URL_0_), although others here have covered the basics. (Fair warning: if you're unfamiliar with Kurtzgesagt, be prepared to lose many hours.)"
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8ol7h6
|
what makes shutting puppy mills down so hard even though they are repeat offenders?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8ol7h6/eli5_what_makes_shutting_puppy_mills_down_so_hard/
|
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"NY Times recently [did an article](_URL_0_) on how rescue groups may inadvertently be fueling some of the fire by spending donation money on auctions for harder-to-find breeds, thereby pushing demand and prices up. It was an interesting perspective that I'd never even thought about and it may tie in to part of your question.",
"Running a puppy mill, by itself, isn't illegal in any state. \n\nMost counties have regulations that require dogs to be licensed or which restrict the amount of dogs that can be in any given area. But the penalty for violating those regulations is usually limited to a small fine. \n\nAdditionally, proving that those regulations are being violated is difficult. Under normal circumstances it requires that the neighbors call animal control out to the house *and* that the dogs are visible from the street. Its really only when one of the dogs actually bites someone else that animal control is able to take action because at that point they can seize the dogs.\n\nIn order to criminalize puppy mills, states would have to criminalize allowing dogs to breed, which isn't something that is practical or enforceable. The closest you can realistically do is what California did - which is to outlaw pet stores from selling \"commercially raised animals,\" but even that doesn't do much since most pet stores have already stopped doing so.",
"Because Missouri.\n\nMissouri has extremely lax puppy mill laws, and is one of the biggest suppliers in the country. Puppy mills make money and contribute to politicians who keep the laws loose.\n\nOther states can and have cracked down on puppy mills, but since they can't compete with Missouri in a state that has strict regulation, it just moves the business out of the state.\n\n",
"Because the puppies are considered livestock in that application and the laws are much less restrictive on livestock than domestic pets.",
"Having a puppy breeding business is not illegal. Only specific actions of negligence in dealing with the puppies and mothers are illegal. Simply being a breeder is not ground for the authorities to attempt to shut you down, there has to be evidence of you actually breaking the law. ",
"My county had an extremely hard time regulating known puppy mills in our area and ended up giving up. The puppy mills were clients of the company you register purebred puppies to. The company got their lawyers involved to fight the county because they would have lost a ton of money. It's sad but my small county gave up the fight.",
"Not in the US. \n\nI reported my uncle for puppy milling and animal abuse. So called authorities sent me around their branches because I live in a different town to my uncle. After that was sorted out they essentially told me they can't do anything because we have no laws and even the laws we have they aren't authorized to enforce. So I stopped supporting them and I've made it clear to everyone why. Doesn't seem to bother anyone that they campaign and market but when push comes to shove then they can't do anything. ",
"Can We PLEASE just add a tax on unspayed and unneutered animals? We make people get them rabies vaccines. Some towns require a license. How hard would it be at that license renewal to tack on a $50 tax if the dog is intact?! The money could go towards low cost spaying and neutering clinics! \"oh but then people would just not license their dogs!\" They're doing that anyway. Add the tax and some accountability. ",
"Perhaps I’m a bad person, and this is in relation to a cat that I bought, but three years ago I decided I was settled down enough and would be for the foreseeable future so I got a kitten.\n\nMy first avenue to procuring my now best friend Winston was to start calling all the shelters within about 15-20 miles of where I live in Los Angeles. Now it’s not like I live in some po-dunk country town where there is only one adoption agency. Since this was around September/October I was told by EVERY SINGLE rescue agency within reasonable driving range that it was not kitten season and that I should try back in six to eight months. Strike one.\n\nNext, I went to several local, reputable pet stores. I was told by them that my only two options for adopting one of their cats was I could adopt a full-grown 5 year old cat OR I had to adopt two kittens. There was no option to adopt just one single kitten. Now I understand that these poor cats that are older have very little options of being taken home by people, but as a single man with a studio apartment I felt it would be irresponsible to adopt two kittens who could potentially not get along immediately or eventually. Strike two.\n\nI started to mull over adopting one of the handful of older cats. I love cats, all of them. However, we all know that cats are a crap shoot and they’re either as loving and affectionate as the best puppies or they are complete assholes who obviously do not like humans, cats, dogs or anyone else for that matter. After scanning through a half dozen pet shops over the course of a week and a half to two weeks I did not find an adult cat who was adoptable that I get any connection to. Some were mean, some were indifferent and then a few even attacked me. It was clear that bringing one of these chaps home would turn my shitty studio apartment in Hollywood into a house of animosity. Strike three.\n\nThen I decided to look on Craigslist. Immediately I found someone in West Hollywood (3 miles away) with two kittens for sale for $150. I went and met these folks and they had a grey female kitten and a blonde male kitten. I mentally flipped a coin and decided to take the blonde kitten (blondes have more fun right?) I took him home and named him Winston, after John Winston Lennon, and he and I have been inseparable since. The point I am making is thus:\n\nTrying to adopt a kitten through the county or a pet shop was almost a month long process that yielded no preferable results. Buying the kitten from a potential “kitten mill” yielded immediate results and I got one of the most affectionate, loving cats I’ve ever met. That was over three years ago and Winston and I are inseparable. So o guess my point is that while potentially unethical, buying from puppy and kitten mills is a much easier and convenient way to bring a cat/dog into the fold of ones life. Also, the county and pet stores insisted that they come to my private home and do a thorough inspection of it. I understand where they’re coming from but my home is private and I didn’t like the idea of a stranger coming into my home to “judge” me. They also wanted to call my work for god knows what reason and obviously they wanted to do a background check. These are all understandable caveats, however these multiple hoops and privacy concerns are the reasons that puppy mills and kitten mills are so popular and hard to eradicate. Fortunately for Winston I’m a loving, responsible roommate and for all those folks knew I was planning to make kitten soup out of this guy. So I agree with all the things the adoption agency was doing. But as long as there are people who want a puppy/kitten to raise from a teeny little ball of fur to a large, flippant animal then people will go around the adoption agencies, SPCA and reputable pet stores. I hope this doesn’t elicit the wrath of Reddit. I assure you my little brother here is the happiest kitten/cat in all of Hollywood.\n\nHope that helps...",
" ill never get why this shit still goes on even being legal because ill never buy a dog myself and ive had dogs be apart of my family my whole life. Someones dog had puppies, i offer to take one off their hands, or ive had stray dogs find me so i let them stay. thats the way it should be",
"Frankly I don't understand why people don't get dogs from a shelter. There are plenty of them and so very grateful for their forever home."
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"https://www.washingtonpost.com/graphics/2018/investigations/dog-auction-rescue-groups-donations/?utm_term=.1ffe8689999e"
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6p6n6r
|
how can reading about something induce the feeling of a physical sensation?
|
The same goes for watching things too. Like witnessing a man being hit in the genitals and then "feeling" pain and being uncomfortable.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6p6n6r/eli5_how_can_reading_about_something_induce_the/
|
{
"a_id": [
"dkn0pxz",
"dko5b0r"
],
"score": [
2,
2
],
"text": [
"Humans have a unique ability to encode feeling into art. One condenses their emotion into a sound or color or series of symbols, and another individual decodes and experiences those feelings with their brain. \n\nIt's completely unique and an astonishing effect of our species' particular evolution. ",
"Google mirror neurons. When we see or image something, the same parts of our brain that actuall experiwnce those things become active. It's somewhat Similar to how dreams work. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
92s86t
|
What happened to polygamous Mormon families after the leadership of the Church of Jesus Christ of Latter-Day Saints disavowed the practice in 1890? Did families just split up, or did any of them continue to practice polygamy in secret?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/92s86t/what_happened_to_polygamous_mormon_families_after/
|
{
"a_id": [
"e38bbp8",
"e38f2nc"
],
"score": [
357,
56
],
"text": [
"This is not a super easy question to answer because there aren't a lot of statistics on mormon families after the first manifesto disavowing the practice of polygamy. On top of that, the records don't usually differentiate between monogamous and polygamous marriages.\n\nThere are a few references about what happened though. The church stated that they did not see the manifesto as an excuse for men to abandon their families and made it pretty clear that their temple marriages still counted and that they needed to continue to support their other spouses. [Abraham H. Cannon diary, Oct. 7, 1890, Nov. 12, 1891.]\n\nMany families seperated/divorced on their own naturally (my guess is that they weren't happy and only stayed together out of religious duty). But others continued continued to support their other spouses but stopped cohabiting with them. [Embry, Mormon Polygamous Families, 13–14; Francis M. Lyman journal, Dec. 15, 1893, Church History Library; Utah Stake High Council minutes, Aug. 5, 1892, Church History Library, Salt Lake City.]\n\nThen you have the families who continued cohabiting and actually continued to live the same as before the manifesto and actually continued to produce offspring into the 20th century. [Kenneth L. Cannon II, “Beyond the Manifesto: Polygamous Cohabitation among LDS General Authorities after 1890,” Utah Historical Quarterly 46, no. 1 (Winter 1978): 24–36.]\n\nThe third group is what I think you were probably most interested in. What it came down to is that the church disavowed the practice of polygamy to protect itself from having it's property taken by the government for not complying with the law. The manifesto was a public cooperation which gave them that protection. The church didn't disavow the practice because they wanted to but as a means of survival. The church basically let those families be and the U.S. government either didn't have the resources and infrastructure in the western United States or didn't care enough to check every family and a confirm the we're not cohabiting. So, ultimately it's a combination of the LDS church accomplishing their goal of protecting their assets and the organizational difficulties the U.S. gov wasn't willing to work through.\n\nEven after the first manifesto the church performed polygamous weddings in Mexico. One of the men in my family history was actually called to take on more wives post first manifesto. His first wife left him because of this and he lived out the rest of his days in Mexico. \n\nP.S. I tried to get references for everything but I don't have them all on hand currently. I'll try to add more a bit later but there are some for you to mull over.",
"Something I’ve never really understood is what happens to all of the “left out” men who don’t have plural wives? If some men have many wives then there must be many men who have no wives. Right?\n\nThe only book I’ve read on the subject of Mormon life is “Under the Banner Of Heaven” by Jon Krakauer which delves into the beginnings of Mormonism and then focuses on today’s fundamentalist who still practice multiple marriages. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
pyxgk
|
Is there a possibility of "adding more cone types" to the human eye?
|
As I understand it, the wavelengths you can see are determined by the type and amount of cone cells in your eyes. Is it possible, with current technology or even in theory, to add more cone types / more cone cells to change what we can see? Is there a possibility of people engineering themselves to actually see ultraviolet, infrared, and beyond in both directions? And if so, is there a theoretical limit to this? (i.e. is there a wavelength that we can't see for reasons other than "not having the right cone type/amount")
|
askscience
|
http://www.reddit.com/r/askscience/comments/pyxgk/is_there_a_possibility_of_adding_more_cone_types/
|
{
"a_id": [
"c3td0no"
],
"score": [
2
],
"text": [
"Yes; in fact, there are human beings alive right now (mostly females) who have 4 cone types (called tetrachromats), and they are able to distinguish between colors that other people can't, and seem to have a richer and more complex sense of color.\n"
]
}
|
[] |
[] |
[
[]
] |
|
3joalp
|
Has the world experienced major migrations such as the current one before?
|
Interested in gauging how 'common' (for lack of a better word) the current situation in Europe is. Ignoring settling the New World and uninhabited lands, has the world seen a major migration such as the current one to an already populated area?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3joalp/has_the_world_experienced_major_migrations_such/
|
{
"a_id": [
"cuqzhdd"
],
"score": [
3
],
"text": [
"Yes, and in fact the [migration period](_URL_0_) is an important part of history. I'm not quite sure what you mean by 'the current situation' though, so I can't really go into much detail. Is it the religious aspect you are getting at, the distance traveled, something else?"
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Migration_Period"
]
] |
|
1nusuw
|
William the Conqueror conquered England. So does it mean that the current royal family has some viking blood?
|
Thanks
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1nusuw/william_the_conqueror_conquered_england_so_does/
|
{
"a_id": [
"ccm8ipl",
"ccmcnx3",
"ccmdhj0"
],
"score": [
9,
11,
3
],
"text": [
"The Norman dynasty became extinct in 1154! After that there were French, Welsh, Scottish, Dutch, and finally German families (in origin) on the throne.\n\nWilliam I and Elizabeth II are very, very, very distantly related (through marriage rather than blood) as all European royalty are, but there is no direct line between the two. \n\nEdit: To actually answer the question - does the royal family have some Viking blood? Yes, but no more than you or me. And apparently there is a direct link after all - thanks to /u/PKW5 for the pointer.\n\n",
"Yes, but likely, so is everyone who has European descent. \n\nMost likely, every white European can, with reasonable confidence, claim descent from William the Conquerer, and at that, any given Norseman who had descendants. William lived in the 11th century, so lets use 1063 for our start date. In genealogy, traditional calculations of generations use 25 years per generation. 2013 - 1063 = 950 years. Divided by 25 equals 38 generations.\n\nThis is important for two reasons. 32 Generations is the point where the number of theoretical ancestors in the 32nd generation (2^32 or 4,294,967,296) is larger than the number of base pairs (in the 3 billion range) in the human genome. In other words, 32 generations is the point where descent is (theoretically) statistically meaningless, and your genetic makeup is just as related to your ancestor as it would be to any random person you aren't descended from and was alive at that time.\n\nIt is important for a second reason because 2^38 equals 274,877,906,944. Yes, that is 275 Billion. That is the number of theoretical descendants of the old Bastard, assuming 2 children per generation (and for the record, he had ten known issue, so I'm being conservative in my estimates). Obviously, there is a LOT of closed loops there to account for the fact this number is orders of magnitude above the total number of people who have ever lived.\n\nEven if we assume something like 90 percent of the lines go into dead ends before reaching modern times (which most genealogists wouldn't support anyways, if anything, it is the opposite), that's still 27,500,000,000 living descendants right now, so many times over what the current world population is.\n\nSo what is my point here? It is that you don't need to go very far back before claiming anything special about your ancestry becomes meaningless. Anyone who is of European ancestry is almost certainly descended from Charlemagne for instance, and probably William I as well. In fact, you can find estimates that place the most recent common ancestor of Europeans as having lived only *600* years ago (possibly a bit optimistic).\n\nNow math is not exactly my forte, but if I visualize it correctly, if the population of the world is ~7 billion, and the theoretical descendants that this guy has now is 274,877,906,944, that is 40 theoretical descendants who should exist for every person currently alive. So if every person now alive can claim descent from him, they should, in theory, be able to trace back through 40 different paths, right?\n\nIf 1/10th of the world population is descended from him, the average descendant would be able to do it through 400 different paths! Aside from just being an interesting exercise in how closely we are related, this also relates back to the 32 generation cut off point. Because there are so many \"closed loops\", as I think of them, it means that that cut off point potentially gets pushed back.\n\nAlso, going back only a few more generations, to Charlemagne, we are getting into numbers in the trillions by the way.\n\nNow anyways, to get back onto the topic, yes, as the Queen is a direct descendent of William the Conqueror, himself a descendant of the Norse, she would have ancestry of the Norse too, but as I pointed out, there are two huge asterisks. First, it is so far back as to be nearly genetically meaningless, as I pointed out. The second, and more important factor, is that what separates the Queen from everyone else of European descent isn't that she descended from these royal figures and that most people didn't, but rather than because of her specific line of descent being notable, we have the records of it still, while most people simply lack the written proof.\n\n*Also, obviously, I do not take infidelity or adoption into account here, and take paternity at face value. If William kept getting cuckolded, and none of his kids were actually his, obviously none of this still applies.",
"Elizabeth Windsor is a 28th-generation descendant of William of Normandy. [Here's the official family tree of the British monarchy](_URL_2_), showing the line of descent. \n\nInterestingly, she's descended from King William I via a non-royal branch of descendants of King Edward I's, which later married into the Scottish royal family: Edward's non-royal great-great-granddaughter married King James VI of Scotland, who became King James I of England.\n\nThe line of descent also goes through the non-royal Electors of Hanover, as a result of the British Parliament giving the throne to Georg Ludwig, Elector of Hanover, in 1714, as the closest Protestant relative after the death of Queen Anne (they skipped over 50 closer relatives because they were Catholic!).\n\nThis, of course, assumes that every *official* child of a father is also their *actual* child. For example, there have been suspicions and rumours about the legitimacy of more than one British monarch. Tony Robinson [made a documentary](_URL_1_) tracking down the \"true\" current British monarch, based on the strong rumour that King Edward IV was illegitimate. There has also been speculation about Queen Victoria's legitimacy, given that she is the first person in the British royal family to have haemophilia.\n\n\nIt's also worth pointing out that Elizabeth has 2^28 = 268,435,456 ancestors at the 28th generation - which is about 7 times [the total population of Europe at the time](_URL_0_). Even if she didn't inherit Viking \"blood\" throiugh William of Normandy, she probably got it from someone else in her ancestry!\n"
]
}
|
[] |
[] |
[
[],
[],
[
"http://www.fordham.edu/halsall/source/pop-in-eur.asp",
"http://en.wikipedia.org/wiki/Britain's_Real_Monarch",
"http://www.britroyals.com/royaltree.htm"
]
] |
|
1rpss5
|
How historically accurate is "Aztec" from Gary Jennings?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1rpss5/how_historically_accurate_is_aztec_from_gary/
|
{
"a_id": [
"cdpnvp3"
],
"score": [
23
],
"text": [
"If you don't mind spoilers, Aztec scholar mike smith wrote [a review of the book](_URL_0_). \n\nBasically, it's reasonably accurate but not perfect. Jennings does a good job covering the major aspects of Aztec culture and gives the reader a good 'feel' for what life would have been like, but many of the details are wrong. A few notable errors he makes:\n\n1. The Aztec writing system was less flexible than Jennings makes it out to be. It could only record a few kinds of information. History? Yes. Financial records? yes. Personal correspondence? probably not.\n\n2. The main character is way more liberal with sex than the Aztecs would have been comfortable with. \n\n3. The way he depicts the Tarascans ('Michoacan') is pretty much entirely wrong. Smith doesn't talk about it, but it did bother me.\n\n4. A few of the violent details surrounding human sacrifice and the conquest have been exaggerated for dramatic effect. Human sacrifice was brutal, and so was the conquest. But Jennings kind of goes out of his way to make it gut-wrenchingly awful. For example, he describes the priests raping a sacrifice to Xipe Totec, and he describes the conquistadors feeding Indians to their dogs at Cempoala. Neither of those things happened - he added them to make it more dramatic.\n\nIn all, I'd say it's probably 80-85% accurate. As reasonably accurate as can be expected of a work of fiction."
]
}
|
[] |
[] |
[
[
"http://works.bepress.com/cgi/viewcontent.cgi?article=1030&context=michael_e_smith&sei-redir=1"
]
] |
||
b16foc
|
how can sunscreen keep your skin from aging while still sitting in the sun long enough to tan?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/b16foc/eli5_how_can_sunscreen_keep_your_skin_from_aging/
|
{
"a_id": [
"eijmvif",
"eijo159"
],
"score": [
3,
4
],
"text": [
"Not quite. Sunscreen protects against **too much** solar radiation. Depending on how easily you burn, you can decide how strong a protection you want, whilst still allowing yourself to tan.\n\nNow, **don't do this at home. Or *anywhere* come to think of it**. But imagine this. If you put your hand in boiling water it's going to hurt and cause serious damage. Blisters and boils and pain. But if you put your hand in warm water, you can keep it in for much longer.\n\n*That's what sunscreen does*. It turns the boiling sun rays into warm sun rays. ",
"To answer your title: No, it can’t. \n\nTo answer your other question: Yes it’s basically the same damage, you can’t have a sun tan without skin damage, and skin damage leads to what looks like “quicker aging”. So sunscreen cannot “keep your skin from aging” it just keeps your skin from getting sun damage. \n\nSunscreen works by reflecting the sun before it reaches your skin, the same way clothes do. It’s kind of like if you were to grind up tin foil, mix it in paste, and spread it on your body. The sun bounces off and you don’t get sun damage. Sunscreen also contains lotion which helps the skin look younger. \n\nHowever, sunscreen does not block 100% of the sun. The SPF value tells you how effective it is at blocking the sun. SPF 15 will block about 94% of harmful sun rays, while SPF 50 will block about 98%. Sunscreen will also wear off after a while, usually through sweat or swimming etc, so if you don’t re-apply after a couple of hours you’ll get sun damage that way too. \n\nIf you have sensitive skin or you care about skin damage or skin aging effects, then you shouldn’t be getting sun tans. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
92ln6t
|
what does the 101 in beginners courses mean ?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/92ln6t/eli5_what_does_the_101_in_beginners_courses_mean/
|
{
"a_id": [
"e36kesh"
],
"score": [
3
],
"text": [
"It was introduced when colleges begin to organize course work systematically. Courses starting with a 1 are intended for freshman, 2 for sophomores, et cetera.\n\nThe second digit is the content area and third digit the sequence. So the 101 is introductory course. 102, 103, etc should be take sequentially.\n\nEdit: 101 became the socially accepted indicator for introductory courses. "
]
}
|
[] |
[] |
[
[]
] |
||
bdxwkx
|
Are there historical records to document the provenance of religious artifacts like those kept in Notre Dame cathedral?
|
I read/saw in news reports that Notre Dame cathedral housed artifacts such as a crown thought to be part of the crown of thorns Jesus wore on the cross, or a nail and a piece of wood from the cross. As a former Catholic, now atheist, I have always been skeptical of the authenticity of such objects. Is there any effort to make historical documentation of these artifacts? For example, was the crown taken by someone whose name/identity was established and is there a “chain of custody” in any way?
It seems like so many religious artifacts are of dubious authenticity. They always seem to “appear” in the Middle Ages with a vague backstory. But that’s just my amateur opinion.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/bdxwkx/are_there_historical_records_to_document_the/
|
{
"a_id": [
"el1x87t",
"el24twa"
],
"score": [
3,
6
],
"text": [
"There's no evidence, to my knowledge, that any relics that claim to be from the time of Jesus of Nazarene are from that period and region. Saintly relics are a much more mixed bag, since some saints are known in historical records to have died and then been interned in a particular place.\n\nIt's sort of an answer to a question exactly inverse of yours, but here's an excellent previous answer by /u/ [Philip\\_Schwartzerdt](_URL_1_) on how [you could fake a relic.](_URL_0_) Naturally, talking about the methodology of passing off counterfeit relics involves talking about the entire trade.",
"The chain of provenance is surprisingly detailed for a number of holy relics and artifacts across Europe, but only to a point. They all had to find some point of origin and these origin stories would typically be unsatisfying to the modern historian.\n\nTake, for example, the shards of the True Cross. Looking to hagiography, the true cross was supposedly found by St. Helena, the mother of Emperor Constantine, when she was sent to the Holy Land in search of relics by him in 324 CE. The most common narrative you'll encounter in Western Christianity recounting this story is Jacobus da Varagine's *Golden Legend*. In the third volume, he states that:\n\n > Constantine his son remembered the victory of his father, and sent to Helena his mother for to find the holy cross. Then Helena went in to Jerusalem and did do assemble all the wise men of the country, and when they were assembled they would fain know wherefore they were called. Then one Judas said to them: I wot well that she will know of us where the cross of Jesu Christ was laid, but beware you all that none of you tell her, for I wot well, then shall our law be destroyed...Then Judas made him ready and began to dig, and when he came to twenty paces deep he found three crosses and brought them to the queen, and because he knew not which was the cross of our Lord, he laid them in the middle of the city and abode the demonstrance of God; and about the hour of noon there was the corps of a young man brought to be buried. Judas retained the bier, and laid upon it one of the crosses, and after the second, and when he laid on it the third, anon the body that was dead came again to life.\n\nAs you can well imagine this story is likely not quite accurate. It was also written nearly a thousand years after the fact. **The earliest historical references to the Helena story are from Socrates Scholasticus, Theodoret, and Sozomen, all writing between 400-450 CE.** While some details vary the general nature of the Helena story is consistent. What we know is that *a* cross was venerated in Jerusalem as far back as the 300s CE and its discovery was attributed to St. Helena.\n\nNow how did some fragments from a cross dug out of the ground in Jerusalem in 324 CE end up at Notre-Dame de Paris in 2019? Like so many other relics found across western Europe today, via Constantinople. The Latin Emperor Baldwin II sent fragments of true cross relic to King Louis IX of France, likely around 1245 CE during his travels in France and Italy. He gave large numbers of relics to Louis IX in exchange for military support and funds--the Latin Empire was essentially bankrupt; Baldwin also rather notably pawned the Crown of Thorns to Venice for a payout of 13,134 hyperpera in 1238 (this later ended up in France after Louis purchased it from the Venetians). The number of relics that arrived in Paris led to the construction of Sainte-Chapelle to house them.\n\nIn a sense we are lucky with the Parisian true cross fragments. Unlike many relics, there is a fairly clear chain of custody leading it into the present. The problem, of course, is that we have no idea where this original piece of wood came from, and we can't really compare the Paris fragments to the \"original\" because the Jerusalem relic was lost to Saladin in the Battle of Hattin and never seen again.\n\nSpeaking generally, though, there are countless fake relics across Europe. There are also countless relics with long histories. Generally speaking the strength of the \"history\" will depend on the prominence of the relic--when such things are exchanged between monarchs or leading prelates, at least some kind of recounting tends to exist. But a huge number of relics flooded into Europe with the loss of the Eastern Roman Empire to Muslim expansion (and, of course, the Latin occupation of Constantinople in the 13th century). For a fairly good popular history coverage of this process, you could check out:\n\nWells, Colin, *Sailing from Byzantium: How a Lost Empire Shaped the World* (Delacorte Press, 2007). \n\nFor a more academic view on the process of the relics moving to France, I'm afraid I can only recommend some French language titles: \n\nDurand, Jannic. \"Les reliques de Constantinople.\" *Dossier d'archéologie* 264 (2001).\n\nDurand, Jannic. *Le trésor de la Sainte Chapelle* (Paris: RMN, 2001).\n\nLe Goff, Jacques. *Saint Louis* (Paris: Gallimard, 1996)."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/6zu9er/i_am_a_medieval_con_artist_who_wants_to_pass_off",
"https://www.reddit.com/user/Philip_Schwartzerdt"
],
[]
] |
|
25snz8
|
How did the USA phrase laws to keep people they didn't want to from voting?
|
I was wondering how the USA kept blacks, people without property and women from voting, because I can't see them going: "Black people can't vote."
What were the exact wordings and did people try to get around it with creative interpretations?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/25snz8/how_did_the_usa_phrase_laws_to_keep_people_they/
|
{
"a_id": [
"chkedx0"
],
"score": [
9
],
"text": [
"It varied in place and time. One popular trick was to put a difficult barrier like a literacy test in the way, and then to put in a clause that would allow you to vote if you had been a voter prior to a certain date, or later if your father or grandfather had been a voter.\n\n[Here](_URL_0_) is a copy of the voting rules from the Louisiana Constitution of 1898. And I've excerpted some of the key pieces below:\n > He shall be able to read and write, and shall demonstrate his ability to do so when he applies for registration... \n\n > If he be not able to read and write, as provided by Section three of this article, then he shall be entitled to register and vote if he shall, at the time he offers to register, be the bona fide owner of property assessed to him in this State at a valuation of not less than three hundred dollars... \n\n > No male person who was on January 1st, 1867, or at any date prior thereto, entitled to vote under the Constitution or statutes of any State of the United States, wherein he then resided, and no son or grandson of any such person not less than twenty-one years of age at the date of the adoption of this Constitution, and no male person of foreign birth, who was naturalized prior to the first day of January, 1898; shall be denied the right to register and vote in this State by reason of his failure to possess the educational or property qualifications prescribed by this Constitution\n\nSo the rules in Louisiana were, literacy (to the satisfaction of the registrar), property ownership, or descent from a voter in 1867. Well few to no blacks were going to qualify under that. And there was a generally feeling that if they disenfranchised a few poor whites as well, I'm not sure the richer whites were too worried about that.\n\nLouisiana's literacy test 1898 was a simple signature. But they later got pretty elaborate. And some would have word problems or math, and would have multiple trick gotta questions in them. And then they would have outs for white applicants where people who were \"known\" to be literate wouldn't have to take the tests."
]
}
|
[] |
[] |
[
[
"http://www.yale.edu/glc/archive/1154.htm"
]
] |
|
238bla
|
How did Mary, the mother of Jesus, become the center of cult-like worship in the Catholic church?
|
Where in history did early Christians start to associate Mary with extra-biblical power? Throughout the history of the Catholic church, how has this worship fluctuated and why?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/238bla/how_did_mary_the_mother_of_jesus_become_the/
|
{
"a_id": [
"cguimv9",
"cgukmdh",
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"score": [
7,
10,
3
],
"text": [
"It seems like this is a loaded question and goes against the rules of the subreddit. Catholics do not worship Mary any more than Protestants worship John the Baptist, Lutherans worship the saints, or Moslems worship Muhammed.",
"Some corrections before we get going in earnest:\n\n > How did Mary, the mother of Jesus, become the center of cult-like worship in the Catholic church?\n\nTwo points here. First, the Christian devotion to Mary is a cult in the specific and technical use of the word. That is, it is a religious devotion centered around ritualized behaviors. Secondly, no one worships any saint no matter how popular they are. Saints may be *venerated*, but to worship them is idolatry. The term \"veneration\" signifies that you are offering the saint respect but recognizing that the source of their holy power is God.\n\n > associate Mary with extra-biblical power\n\nIt's a bit of protestant polemic to say that Mary has \"extra-biblical power\" because it means you take for granted that the Bible is interpreted in a certain way. A Roman Catholic interpretation of the Bible is certainly compatible with Mary's \"power\". To note once more - no saint has power except by the gift of God.\n\n > my basic hypothesis is that Mary achieved cult-status amongst early Christians\n\nThis is not so much a hypothesis as it is a fact, although one which is much less evident and which requires substantial localization depending on how you define \"early.\"\n\n > Contemporary Christianity and Protestants agree that prayer to Mary is unnecessary and not biblically founded\n\nMany protestant sects will agree with you, but as a blanket statement it is categorically false.\n\nNow that's out of the way, let's get to the heart of the matter.\n\nThe reasons why Mary became an exceptionally popular saint and intercessor in Roman Catholicism are so numerous and intricate there is no way for me to address all of them here. The Christian emphasis on virginity, the particular way Mary satisfied certain spiritual needs, and the support of certain powerful and vocal ecclesiastics are all among the contributing factors. There are many excellent books on the subject, and I would look at work by Carolyn Bynum, Amy Remensnyder, and Rachel Fulton Brown, among others, if you want to dig deeper. Here, I'm going to focus on one of the larger components.\n\nAlthough this may seem at odds with what you have been told, women are extremely important to Christianity in the first four centuries of its existence. Most of the modern conversation focuses on women in liturgical roles which leads to a murkier and more varied picture, but women, and in particular wealthy women, were some of the main benefactors of the early Church. In late antiquity, following the model of the Empress Helena, the mother of Constantine the Great, this long tradition of female benefactors became subsumed into the role of the queen.\n\nBy the sixth century, after the western Empire had fallen and the Merovingians and Lombards ruled in their place, the queen was the merciful counterpart to the king. Where a king would wage war, order executions, and pass judgment, it was the queen's prerogative to dispense mercy, give alms, and, most importantly, to release prisoners. This understanding of queenship far outlasted the middle ages.\n\nParalleling the relationship between Constantine and his mother Helena, Christ rules heaven accompanied by his mother Mary. One of Mary's titles in the Roman Catholic Church is \"Queen of Heaven\" and this has always been understood in a very literal fashion. Mary is the queen *par excellance*, and she maintains all the attributes associated with her lesser earthly equivalents. Just as a mortal queen could order a man justly sentenced to die be freed from his captivity and punishment, Mary, by her relationship to Christ, could ensure that a sinner, justly doomed to an *eternal* death, was likewise freed from the consequences of his crimes. Mary's role as forgiving queen is most evident in her many miracles which involve the salvation and redemption of wicked and undeserving men and women.\n\nFrom the beginning of the development of the cult of saints Marian devotion was never really unpopular, but it only became extremely so in the high middle ages. There are, again, nearly infinite reasons for this, but one among many is a man named Bernard of Clairvaux (d. 1153). Bernard was a Burgundian noble who in 1113 joined a newly-founded and reform-minded Benedictine monastery at Cîteaux in central France. By 1115, Bernard was abbot of his own monastery at Clairvaux, and the fledgling Cistercian order exploded across Europe, growing to over 350 monasteries by Bernard's death. Bernard was not technically the head of the Cistercian order - that honor fell to the abbot of Cîteaux - but he concentrated on its expansion. He entered the mainstream of ecclesiastical politics for the first time in 1128 when he argued for the creation of the Knights Templar in his book *De laude novae militiae* - *In Praise of the New Knighthood* - and he would later help write their Rule. Two years later Bernard proved a pivotal voice in rallying support behind Pope Innocent II in a papal schism, and he was soon seen as the one of the most powerful and well-known churchmen of his day. When one of Bernard's disciples was elected Pope Eugine III following Innocent's death in 1143, he was more or less the most powerful man in Europe and was often called a \"second Pope.\" Bernard was instrumental in the preaching of the Second Crusade, and the book of advice on the papal office he wrote for Eugine, *De consideratione*, is still read by popes today.\n\nBernard, and the Cistercians more generally, were greatly devoted to Mary. Using his power, his popularity, and the popularity of his order, Bernard was instrumental to the popularization of Marian devotion in the West. At the same time, there were vast cultural forces on the move. Scholars generally draw a line between two \"forms\" of medieval piety, a split which occurs roughly somewhere between 1215 and 1250. To paint a really rough picture, tied in with an increased clerical emphasis on lay religious education, most noticeable in the decrees of Lateran IV in 1215, religious experience was shifting out of the domain of the upper classes and spreading into the broader population.\n\nThis later medieval piety was *profoundly* concerned with individual sinfulness and the impossibility of redemption. As an illustration, I have personally read late medieval indulgences which offer the remittance of **46,000 years** of purgatory for saying a sequence of prayers, and it is important to note that this would be considered a drop in the bucket. Now, remember the role of the queen in pardoning the guilty? And remember that Mary was seen as the highest queen, able to perform the same tasks on a cosmic scale? Is it any wonder, then, that she was the object of such intense devotion?\n\nSome reading:\n\n* Vauchez, André. Sainthood in the Later Middle Ages. Cambridge: Cambridge University Press, 1997.\n\n* Brown, Peter. The Cult of the Saints: Its Rise and Function in Latin Christianity. Haskell Lectures on History of Religions 2. Chicago: University of Chicago Press, 1981.\n\n* McNamara, Jo Ann, John E Halborg, and E. Gordon Whatley, eds. Sainted Women of the Dark Ages. Durham, N.C: Duke University Press, 1992.\n\n* Bynum, Caroline Walker. Holy Feast and Holy Fast: The Religious Significance of Food to Medieval Women. The New Historicism : Studies in Cultural Poetics. Berkeley: University of California Press, 1987.\n\n* Huizinga, Johan. The Autumn of the Middle Ages. Chicago: University of Chicago Press, 1996. **(Read with caution and skepticism)**",
"I'm going to take a different tack to /u/telkanuru and talk about some of the doctrinal developments in relation to Mary in the early period, and some of the sources for later Catholic understandings of Mary.\n\nThe main *distinctives* about the Roman Catholic church's teaching about Mary include:\n\n1. Perpetual Virginity\n2. Immaculate Conception\n3. Theotokos\n4. Assumption\n\nThe doctrine of perpetual Virginity is the idea that Mary was not only a virgin prior to giving birth to Jesus, but remained so afterwards. You can find early evidence for this kind of belief in the 2nd century [Proto-evangelium of James](_URL_0_), chapters 19-20. The idea appears widespread by the 4th century, as attested by referring to Mary as \"ever-Virgin\", for example in Athanasius' [Contra Arianos, 2.70](_URL_1_). This idea probably developed in tandem with the growing emphasis on virginity and celibacy within the church, you can see that idea already in the aforementioned Proto-evangelium.\n\nThe doctrine of immaculate conception states that from the moment of her being conceived, Mary was kept free from original sin, thus receiving the grace that Roman Catholics normally identify with baptism. This doctrine was not formally defined until 1854. As far as I know there is no explicit textual expression of this idea in Antiquity, and Pius IX who decreed it admits the same, that it was not explicitly put forward until the 12th century. For that reason I will leave it alone as outside my field.\n\nThird, Mary was given the Greek title Θεοτόκος, this is often translated as \"Mother of God\", but a more overly-literal translation might be \"the one who gave birth to the one who is God\". The title refers to the fact that, because of the understanding that in Jesus there are both divine and human natures, distinct yet indivisable, but there is only one person, anything that is predicated of one nature is predicated of the person. This means that because Mary gave physical birth to Jesus, she gave physical birth to the one who is God. It does not mean that Mary gave birth to God. I realise this paragraph is probably difficult to follow, but that's because 5th century theological debates are technical and precise.\n\nThere is some evidence of the use of this title in the 4th century, but it becomes important in the 5th century debates over Jesus' two natures and how the relate. This is the conflict between Nestorius and Cyril that results in the Council of Ephesus in 431 and the Council of Chalcedon in 451.\n\nThe last major doctrinal distinctive of Roman Catholicism in regards to Mary is the Assumption, that is that Mary at the end of her earthly life was physically \"taken up\" into heaven, similar to Enoch in Genesis of Elijah in 2 Kings, though the exact formulation of those two events within RC theology is not something I am familiar with. The earliest text that explicitly affirms this is The Book of Mary's Repose, which survives in an Ethiopic translation, from no earlier than the 3rd century; there are also some traditions in Syriac from the 6th century. It's not entirely clear how this assumption took place, in that the Orthodox view is that Mary died and was raised 3 days later and then taken up into heaven. This is a possible understanding of the RC view as well. Anyway, it's not attested within the early church in Greek or Latin, and so again that puts it outside my expertise.\n\n\nThere are other issues to consider, especially the growing role of saints as intermediaries, of Mary in particular, of veneration of saints and prayer directed via saints to God, but I will leave that aside for now.\n"
]
}
|
[] |
[] |
[
[],
[],
[
"http://www.ccel.org/ccel/schaff/anf08.vii.iv.html",
"http://www.ccel.org/ccel/schaff/npnf204.xxi.ii.iii.viii.html"
]
] |
|
77ymhg
|
Cost and protection of cloth armour?
|
In 13th to 14th century England could cloth armour alone protect you from longbows and crossbows? Was it cheap enough that everyone could wear? How much material would be needed to make one?
Thanks in advance.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/77ymhg/cost_and_protection_of_cloth_armour/
|
{
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"text": [
"There is an extensive discussion of the protection provided by armour in section 9 of Alan Williams *The Knight and the Blast Furnace* (Brill, 2003). This focusses on iron/steel armour, but reports some results for non-metallic armours.\n\nLongbows and crossbows can deliver 200J of energy at short range. To stop this with plate armour, 2mm (backed by a few layers of cloth) should suffice, if the iron/steel is of good quality. Unsurprisingly, late Medieval breastplates of 2-3mm in thickness are common (older thinner Medieval breastplates may have been intended for wear over mail).\n\nFrom the experimental tests reported in Williams, 30 layers of cloth will stop an arrow with about 100J of energy (comparable to 1-1.2mm of iron or unhardened steel). To stop arrows from high draw weight longbows and crossbows, one would want 60 layers.\n\nNoting that 30 layers of linen will weigh about the same (per unit area) as 1.2-1.5mm of iron/steel, arrow/crossbow-proof textile armour will weigh somewhat more than equally-protective iron/steel plate. A breastplate of about 2mm thickness will weigh about 2.5kg, so similar protection for textile armour for the front of the torso, neck to waist, will weigh about 3kg (and be much thicker). A complete gambeson with such protection for the front of the torso will be heavier."
]
}
|
[] |
[] |
[
[]
] |
|
5tw8n4
|
how x-ray machines work and what metal is typically used
|
Title is self explanatory.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5tw8n4/eli5_how_xray_machines_work_and_what_metal_is/
|
{
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"ddpmx2c"
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"text": [
"They work similarly to CRT televisions, interestingly.\n\nThere is an 'electron emitter', which generates a cloud of electrons around a coil. Then there is an 'electron collector', that pulls the electrons to itself with great acceleration. This acceleration gives the electrons their energy, with which they crash into an angled piece of metal. When they crash into that metal piece, they 'excite' it, and cause it to emit high energy photons, which are called the x-rays.\n\nThe metal target gets *very* hot in the process. I know that, due to its ridiculous heat resistance, tungsten was a popular choice for target material, but my knowledge on x-ray tubes is very superficial. They might be using some fancy alloys."
]
}
|
[] |
[] |
[
[]
] |
|
3j56pr
|
why do dogs eat grass?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3j56pr/eli5_why_do_dogs_eat_grass/
|
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"Both my dogs chomp grass when we go to the park. At first I thought that my dogs were getting upset tummies but nope, they just like grass. ",
"My labrador, possibly labrador/goat mix grazes grass everyday. He never throws up or shows any signs of an upset stomach and has solid poops. \n\nI just think he likes it.",
"Anecdotal, but mine only does it when it's close to mealtime and he hasn't been fed yet, or when there's (apparently) ultra delicious cool morning dew on the grass. ",
"Mine do it out of spite. I just looked into this because mine do it non stop. Basically they don't know for sure could be compulsive behaviour, could be remedy, could be spite.\n",
"Maybe boredom? Maybe its tasty? My dog eats grass a lot and he has no stomach problems. You shouldn't worry about it endagering your dog unless you treat your grass with chemicals and stuff.",
"_URL_0_\n\nA large portion of dogs eat grass, very small percentage do when they are ill, and about 22% vomit on a somewhat consistent basis. Dogs who are ill are more likely to vomit when eating grass. Dogs do it so often when they feel well, its hard to imagine that they do it to make them selves puke and feel better. If you read the link, it will explain how one theory is in the wild, the grass would provide fiber to help in the digestive track, and remove worms and other parasites. The theory is that the dogs still carry this instinct that helped their ancestors, and eat grass; even though they don't have the parasites that it would aid for.\n\nAnother theory I've read, but I don't know from where, could of just been a reddit comment; saying that it could be your dog is bored, and isn't getting enough exercise, but my friend has a couple dogs on some acreage, and they run a ton and play together; but one of them still eats grass sometimes, or will chomp on part of a plant.",
"Wait, so dogs actually *can* eat grass?",
"Sometimes when their tummy is upset they eat grass to tickle their throat and cause them to vomit up whatever is bothering them. Other times they may be eating it to get a nutrient their food isnt supplying enough of.",
"Lots of bermuda grass here in Arizona. My dog doesn't care for the closely mowed grass. She looks for places where there are taller blades with new shoots and grazes the tops off them. I think she just likes the taste. ",
"My dog eats grass every single day, he seems to like the taste of only a certain type of grass that is different than the type of grass his friend likes and my previous dog liked.\n\nIt's kind of interesting, I always hear people say that it's because they aren't feeling well or to throw up but in all honesty I haven't met a dog that didn't eat grass if given the option. They just seem to like eating grass, some more than others.",
"Multiple reasons. Most often to aid an upset stomach be it through just aiding digestion or to induce vomiting, but a handful of under-stimulated dogs will do this just out of boredom. ",
"Dogs eat grass when their stomach feels bad. Grass makes them throw up so the feeling goes away since they can't put a finger in their throat like we do",
"Your doggie sometimes eats grass to help with tummy aches or if they ate something that didn't agree with them. But dogs and cats also think it tastes yummy, so will occasionally have it as a snack. It doesn't always mean something bad! \n\nEdit: in your dog's case, he/she may have gotten into the garbage, eaten something bad outside, or may have been fed at a different time than usual. Some dogs just have sensitive stomachs. ",
"My dog is a Germans Shepard and golden retriever mix, and probably some Fucking Billy goat in there because Damn can he eat grass. Which he does to calm his stomach, and then puke on my floor. "
]
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|
[] |
[] |
[
[],
[],
[],
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[],
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||
6udhsk
|
do steroids actually enlarge the head?
|
I'm thinking of the claims that Barry Bonds' ballooned in the late 90s after he started taking steroids.
Is this a real effect, and, if so, why does this happen?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6udhsk/eli5_do_steroids_actually_enlarge_the_head/
|
{
"a_id": [
"dlrwmtb"
],
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"text": [
"Moon face is the result of fat distribution to the face--the head is not actually getting bigger. It's a common side effect of Prednisone, an immunosuppressive corticosteroid, but can also result from prolonged anabolic steroid use. The specific mechanism that causes this is not known, but longer use generally corresponds with more prominent showing."
]
}
|
[] |
[] |
[
[]
] |
|
3wscjd
|
why did a radical islamist behind a school attack shout "it is for daesh" if "daesh" is a horrible insult?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3wscjd/eli5_why_did_a_radical_islamist_behind_a_school/
|
{
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"text": [
" > Daesh is an acronym for the Arabic phrase al-Dawla al-Islamiya al-Iraq al-Sham (Islamic State of Iraq and the Levant)\n\nMaybe is has some other meaning but it seems its just an acronym \n\nSo, yeh, he's pretty much saying \"for ISIS\"\n\nEdit: Further searching I found this from an article\n\n > The word is an Arabic acronym of al-Dawla al-Islamiya fi Iraq wa ash-Sham – meaning the Islamic State of Iraq and al-Shams – but Daesh when spoken sounds similar to the Arabic words for \"the sowers of discord\" (Dahes) or \"one who crushes underfoot\" (Daes).\n\n\nThey dislike it because of the sound \n",
"I think the truth behind your question just came out, apparently the guy is being questioned by police about why he lied about the whole thing"
]
}
|
[] |
[] |
[
[],
[]
] |
|
7qoa4m
|
how will humanity determine if free will is a myth?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7qoa4m/eli5_how_will_humanity_determine_if_free_will_is/
|
{
"a_id": [
"dsqn2se"
],
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"text": [
"You don't know what is real and isn't. Therefore, you don't know if you can freely interact with anything because you don't know if it exists. This means it's not possible to determine... but that's just my take. For more information, look into metaphysics (or do yourself a favor and don't)."
]
}
|
[] |
[] |
[
[]
] |
||
bafad7
|
If you relocated a sea turtle's nest to a completely different location, would the babies return to where the mother laid them or where the human relocated them to nest?
|
askscience
|
https://www.reddit.com/r/askscience/comments/bafad7/if_you_relocated_a_sea_turtles_nest_to_a/
|
{
"a_id": [
"ekbttvi"
],
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6
],
"text": [
"Salmon, I know, not a turtle, salmon exhibit this behaviour. Salmon are caught at fish-ladders and eggs removed, these are hatched and the just born salmon then are released in various rivers and creeks etc. These salmon now return to where they were released, not where the parent was born. "
]
}
|
[] |
[] |
[
[]
] |
||
17y0q2
|
Jellicoe, Beatty, and the current perception of the admirals of Jutland?
|
Searched for all the relevant terms, couldn't find much on this sub about this and wanted to pose a few questions I had about Jutland.
The facts of the engagement are pretty clear-cut; with Beatty finding the Germans and making an error or two, but still drawing them in. Jellicoe crosses the T twice in an hour, Germans sink twice the tonnage they lose, escape in the night. I'm curious about the modern view of historians of the performance of the admirals in the battle.
Beatty seems to have quashed some contemporary criticism of himself post-war, despite some clear-cut "errors". Were these the kind of mistakes any admiral could make, and did they play a decisive role in the battle, well, not being decisive? Can't really blame the guy for using his position to improve his own image, 95% of all people would do the same. I had a history professor at college in Chicago who was a Beatty fan because he was married to Marshall Field's daughter, but that's the extent of my education about the man outside of Wiki.
Jellicoe seems to have been the guy Britain WANTED to be a war hero. Is this accurate? It's as though they were looking to create the next Nelson, but like Babe Ruth or Hulk Hogan, the heroes of the past had achievements it was near-impossible to match. So Jellicoe crosses the T twice, is unable to strike a decisive blow, and still gets a statue in Trafalgar square. Does he get credit for getting his fleet into the right positions and so on or was the public frustration of the day appropriate? Togo had absolutely destroyed the Russians a decade earlier, if he'd been one of the four main admirals here I've gotta believe the battle would have turned out differently.
For that matter, I hear little about Scheer and Hipper. I reckon Scheer's memoirs are a must-read for me on this topic; should they be commended for the performance of their fleet in the battle? They did sink more than they lost, with a much smaller fleet, then got away; of course they did not achieve their objective.
Finally, I've read about First Sea Lord John Fisher's desire to invade the north coast of Germany. Did Jutland affect him losing this political battle or is my timeline off?
I guess I'm looking for what the contemporary view of Jutland is from you historians. It kinda...not to minimize, but it seems much ado about nothing, only famous because of the ships involved/history of battleships, not the results.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/17y0q2/jellicoe_beatty_and_the_current_perception_of_the/
|
{
"a_id": [
"c8a2xep"
],
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2
],
"text": [
"It's far from a unbiased account but here is Jellicoe's version written in 1932: _URL_1_\n\nThere is a book by Pulitzer prize winner Robert Massie called \"Castles made of steel\" that goes into this in depth. He also wrote a book called \"Dreadnaught\" dealing with the lead up to the war. I hearty recommend both books for the insight they provide into the times and personalities of the great war. _URL_0_\n\n"
]
}
|
[] |
[] |
[
[
"http://www.amazon.com/Castles-Steel-Britain-Germany-Winning/dp/0345408780",
"http://en.wikisource.org/wiki/Errors_Made_in_Jutland_Battle"
]
] |
|
3y4uc4
|
why don't other organizations last as long as religions?
|
Islam is nearly 1000 years old, Christianity nearly 2000 and Judaism even older. Are there any nonreligious organizations that have lasted this long? What is special about religion that allows their organizations to last so long?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3y4uc4/eli5_why_dont_other_organizations_last_as_long_as/
|
{
"a_id": [
"cyake1u"
],
"score": [
2
],
"text": [
"I don't know what you mean? Empires sometimes last just as long as, if not longer than religions. \n\nIran is about 5000 years old if you count the proto-Elamite kingdom on the Iranian Plateau as the start of Iran. Azerbaijan could also count under the same kingdom. \n\nChina's oldest dynasty is just older than christianity by about 200 years. \n\nJapan's oldest emperor dates back before christ as well. \n\nAfghanistan has had mixed tribes since about 600BC (maybe a little later) \n\n Bahrain could have been founded as early as 4,000 BCE if you count the Dilmun empire. \n\nEven somolia outdates christianity by about 200 years. \n\nAnd those are countries that are still around! Countries last just as long as religions in some cases. "
]
}
|
[] |
[] |
[
[]
] |
|
fmd0q
|
Particle accelerators "create conditions similar to the time just after the Big Bang". What do Physicists mean by this?
|
askscience
|
http://www.reddit.com/r/askscience/comments/fmd0q/particle_accelerators_create_conditions_similar/
|
{
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"What do we understand from particle physics? We see that electromagnetism and the weak force unify at the energy scale of about 100 GeV. At those high energies, the two forces look the same and can be described by a single mathematical framework. Experimental data also indicates that at even higher energies (10^14 - 10^14 GeV?) we'll find these two forces unified with the strong force as well. As we go to higher energies, we also get to produce and observe more massive particles that you don't see at lower energies. We want to go to these higher energies.\n\nWhat do we understand from Big Bang cosmology? Our universe currently expands, and its homogeneity and the processes by which it was seeded with atoms can be explained by it being much smaller and hotter in the past. If we turn back the clock, we expect to see the universe shrink down and get hotter, with its particles experiencing higher and higher energies.\n\nWhen we say that we're using particle accelerators to create conditions similar to the time just after the Big Bang, we mean that we're creating particles and observing effects that have not been seen abundantly in our universe since those earlier, hotter times.",
"When the universe was too hot and dense for individual protons to form, all the quarks and gluons that would go on to form them were just flying around in state of matter called a quark gluon plasma. When you fire nuclei at each other with enough energy, the particles briefly form a similar state."
]
}
|
[] |
[] |
[
[],
[]
] |
||
7k4hwj
|
How do scholars sift through what is factual and what is mythical about Julius Caesar?
|
[deleted]
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7k4hwj/how_do_scholars_sift_through_what_is_factual_and/
|
{
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"text": [
"In short, it’s almost impossible to judge what is ‘factual’ about Caesar, and the same can be said about anyone from that time period. We can judge whether sources were exaggerated or not based on *some* archaeological finds, but when all you have to go on are written sources from ~2,000 years ago it’s important to keep in mind that some of it might be flat out made up.\n\nThat being said, especially for Julius Caesar, a lot of what is written about him during the Roman period is generally considered true, for the most part, but again it is important for the reader to keep in mind the various biased that might lead to exaggeration and hyperbole in certain sources, either with the aim of ruining or praising Caesar and his reputation.\n\nSuetonius’ *Lives of the Twelve Caesars*, covering Julius Caesar and the first 11 Emperors, is generally considered a mostly factual biography. Suetonius was Hadrian’s imperial archivist, so he had access to basically anything and everything that might have information on Caesar, and was also quite critical and fair in his account, discounting or discrediting certain stories that he himself doubts.\n\nWe also have Plutarch, whose biography of Caesar was written as a counterpart to Plutarch’s own *Life of Alexander the Great*, and was meant to be a parallel between the two men. Of course, with this comes a certain agenda within Plutarch’s biography of Caesar; while I won’t go so far as to say the story is twisted, he will have certainly chosen which parts to include and which parts to exaggerate to better portray the image that Caesar and Alexander (and by extent Romans and Greeks) weren’t all that different.\n\nAnd, of course, we have the writings of Julius Caesar himself. His most famous work, *Commentarii de Bello Gallico*, is generally considered a factual account of his conquest of Gaul, albeit with some exaggerated numbers, but again it is important to keep in mind that the book - and the rest of Caesar’s bibliography - were probably the most biased in Caesar’s favour, being written by the man himself.\n\nGenerally speaking, we can’t really tell how much is factual and how much is mythical with any major certainty, short of a few events. For example, the story given to us by Suetonius that two beings with swords and darts set fire to Caesar’s pyre is almost certainly considered mythical (*Caesar* 84). Of course, that being said, there are plenty of times when we can be absolutely certain of some things. When we read that Caesar built a new harbour at Ostia, we can see that harbour there today, and know when it was built, and the *Forum Julium* in Rome has various inscriptions crediting the construction of the forum to Caesar, which corresponds with his biographies. \n\nSo in terms of judging the reality of Caesar’s life, our best option, ultimately, is to cross-reference between Caesar’s own writings, the biographies about him, old Roman records that might still survive, and the surviving archaeological sources. It’s all down to cross-referencing!\n\nI hope this rambling trash sort of answers your question! I’d highly recommend reading Suetonius, Plutarch and especially Caesar’s *Commentarii de Bello Gallico*, they’re all rather interesting and have some great information in them."
]
}
|
[] |
[] |
[
[]
] |
|
45xdtn
|
What is drift velocity, and what is the difference between that and the speed of an electron?
|
Here's my understanding -
& nbsp;
Drift Velocity - Electrons don't really travel at the speed of light. But wires have a lot of electrons in them. So when we turn the light on, a kind of domino effect is created, where one electron bumps into another, and this happens pretty instantaneously and that's how electricity flows. Individually they're pretty slow, but due to the domino effect, current flows at a pretty rapid rate. And the amount of current is high because the number of electrons per unit volume is very high ( 10^(21) electrons/m^3 or something).And if I remember correctly, the value is something like 10^(-5) m/s or something. BUT
& nbsp;
All that stuff changed when I googled [this](_URL_0_) and [this](_URL_1_). So according to google, both are pretty much the same thing, yet my value for drift velocity is majorly different compared to the one google is giving me.
|
askscience
|
https://www.reddit.com/r/askscience/comments/45xdtn/what_is_drift_velocity_and_what_is_the_difference/
|
{
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"d00swvk"
],
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"text": [
"The domino effect is not really a good way to think of it. Think about it more like a river with a lot of pingpong balls that is blocked off and turning on the switch makes the river flow, causing the balls to move.\n\n\nWhen you turn on the switch an electric field is created, which causes a force to work on the electrons. This means that instead of standing still (when you average their velocity, since they are still moving ofcourse) they will slowly move in the electric field.\n\nSo their actual velocity doesn't change, it's only their averaged velocity that changes, and that average is the drift velocity."
]
}
|
[] |
[
"https://www.google.co.in/search?q=speed+at+which+electrons+travel&oq=speed+at+which+electrons+travel&aqs=chrome..69i57.4598j0j1&sourceid=chrome&ie=UTF-8",
"https://www.google.co.in/search?q=what+is+drift+velocity&oq=what+is+drift+velocity&aqs=chrome..69i57.5982j0j1&sourceid=chrome&ie=UTF-8"
] |
[
[]
] |
|
tvg2p
|
History of Secret Police
|
I was reading a book about the Stasi in East Germany and thought about analogues in distant history, but I have having trouble finding anything which fits type of secret police we see in modern times. This is perhaps due to how I define "secret police", and I don't claim to hold the correct definition, but it seems to imply a few things. *-*Directly answers to the upper echelons of the state and different from simple edicts. *-*Operates to help reduce publicity and prevent outcry. *-*Different from intelligence agencies and regular police.
Institutions which fit this definition seem to be fairly recent. Based on my poor understanding of history, the distant ruler didn't care too much about hiding his activities or maintaining a facade of freedom.
Does this concept have any ancient comparisons? How far back can the "modern secret police" be traced?
edit: to expand the topic, if anyone doesn't mind, what about discrete propaganda agencies?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/tvg2p/history_of_secret_police/
|
{
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"text": [
"You could say the Eyes and Ears of the Persian Empire were a secret police, though they were more a general intelligence agency.\n\nIIRC Imperial (pre-communist) Russia had the first real secret police, in the sense of a spy agency with police powers outside the justice system, answering to the king.",
"The Oprichnina developed by the Russian Tsar Ivan the Terrible is probably the earliest example of a modern secret police. It hunted down political enemies, not religeous disenters. ",
"The early Roman Empire had what were called the \"frumentarii\" or \"grain men.\" The grain suppliers for the army traveled often and were in contact with both military officials and local populations, which led Hadrian to recruit many of them as spies. The frumentarii were not particularly well liked, as so Diocletian replaced them with the \"agentes in rebus\", literally \"doers of things\". They were much better organized and acted as general imperial officials in addition to their role as agents, and could deliver messages and act as diplomats.\n\nunfortunately neither organization is particularly well understood."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
6iubb2
|
why do people get foam in their mouth when they have rabies or an epileptic seizure?
|
Title explains for itself
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6iubb2/eli5why_do_people_get_foam_in_their_mouth_when/
|
{
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"dj96x6f"
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"text": [
"I can explain the seizures (epileptic here): when you have the most severe of epileptic seizures, you lose total control over your body. Obviously the most visible symptom of this is loss of limb control, ie, seizing. But most of the the rest of the body goes too - including the ability to swallow. A basic body survival response to this is blowing spit out to prevent from drowning. The spit comes through the teeth or the sides of the mouth, is aerated (filled with air from the blowing) and thus has extra bubbles that look like foam."
]
}
|
[] |
[] |
[
[]
] |
|
arqo8i
|
If a human body suddenly got sucked up into outer space what would happen to the human body? Why wouldn’t humans flash freeze?
|
askscience
|
https://www.reddit.com/r/askscience/comments/arqo8i/if_a_human_body_suddenly_got_sucked_up_into_outer/
|
{
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"text": [
"I'll answer the second part: a human wouldn't flash-freeze because a vacuum is an extremely good insulator. On a human scale, the thin gas of interplanetary space is so thin that it doesn't really have any temperature at all. There's no convection or conduction of heat out of your body. Instead, there's only radiation - your body is emitting infrared radiation (mostly), and that's the only way it can cool down. At the same time, it's potentially receiving radiation from the Sun, depending on if e.g. you're in the shade behind a planet, and how close you are to the Sun. You're also producing heat with your bodily functions.\n\nThe human body wants to be at about 37° C, but if you're in the same orbit as the Earth, after dying from exposure you'll eventually cool down to about -20°. This is the temperature where the Sun's heat and your body's emission roughly cancel each other out - although it depends on stuff like what colour clothes you're wearing and how shiny they are etc. The Earth's surface is only hotter than -20° because we have the atmosphere to insulate us.\n\nIt would feel cold, but more like being outside in a Canadian winter than being flash freezed.",
"For the first part, you would suffer and extreme case of the bends. All the gasses dissolved in your body and your blood would fizz out, like taking the cap off a bottle of soda. Depending how fast this theoretical expulsion into space happens, your lungs could also burst causing a lung embolism. The gasses escaping so fast from solution in your blood, would probably cause veins to rupture, and as a result bleeding and bruising. Obviously, you will be dead really fast.",
"One guy who was testing space suits in a chamber (I forget what it’s called) had a hole in the space suit and said his tongue went fizzy and he passed out, he was fine though. Here’s a website I found though: \n\n_URL_0_"
]
}
|
[] |
[] |
[
[],
[],
[
"https://www.google.com.au/amp/s/amp.businessinsider.com/what-happens-to-a-human-body-in-space-2015-3"
]
] |
||
audgou
|
how does adding money to be circulated affect the economy?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/audgou/eli5_how_does_adding_money_to_be_circulated/
|
{
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"text": [
"It causes inflation.\n\nWhen the total money in an economy (the money supply) increases too rapidly, the quality of the money (the currency value) often decreases. Economists generally think that this money supply increase (monetary inflation) causes the goods/services price increase (price inflation) over a longer period.\n\n & #x200B;",
"Currency like that in the US has no inherent value. It’s just a piece of paper that we have agreed represents a certain valued amount. The dollar bill is a one dollar federal reserve note. You can’t go into a bank and exchange it for something like gold or silver or diamonds. \n\nThat’s separate from money. You can’t touch money. Money is the numbers in your bank account that tells you how much buying power you have. Currency is what you get out of an atm and trade for real world objects. \n\nAdding currency to circulation does raise inflation because the more paper dollars that are out there, the less each one is worth in terms of actually being traded for stuff of value like food or water. And if the currency is worth less then prices go up. That’s what inflation is. One of the tactics to fight inflation is to print less currency. \n\nAdding money to the economy is different. A bank loans you 10 grand worth of buying power. They don’t remove that amount from their reserves. They add it to their assets. They have created 10,000 that didn’t exist anywhere before and now they show themselves on paper as 10 grand richer and you as ten grand poorer. They in turn can make loans against the ten grand you haven’t paid them yet (that they made up in the first place) and if you stop paying, take possession of your physical assets. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
39sk84
|
since black absorbs light, exactly how much warmer will you be in a black shirt, contra a white one? and also, are black people on average hotter than the rest?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/39sk84/eli5_since_black_absorbs_light_exactly_how_much/
|
{
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"text": [
"Can I add to you question why women in Arabic countries wear black robes (burqas)? Wouldn't it make more sense to wear white ones?",
"Read \"Why do Bedouins wear black robes in hot deserts?\" a paper from Nature. \n\nTurns out that the colour makes no difference and it's how the robe is worn that makes the difference. ",
"I think questions like this are better suited for /r/askscience. Anyway, there's no *exact* answer, it depends on too many variables and a lot of the underlying processes are essentially random. \n\nI think the reason for wearing black clothes is that a good absorber of radiation (= light) is a good emitter as well. So, despite getting hot more quickly in the sun, black skin or clothes also lose the heat more quickly. ",
"Well I don't think black people are \"hotter\". White skin evolved because of a lack of sunlight the further north you go, which is why someone from Sweden is a lot paler than someone from Malta. People in Europe needed a better way to get vitamin D. Darker skin actually protects the person better from UV radiation. People who ate a lot of fish kept their darker skin, like Inuits.",
"I'm not sure, but I believe most of the heat that reaches you is in the infrared spectrum of light. So while a shirt may reflect visible colors, it may not reflect others.",
"If we assume only heat transfer due to radiation, we can use stefan boltzmann law of radiation. We can assume black has an emissivity of 1.0, white... let's go w 0.25. \n\nQ=e*sigma*(t1^4 - t2^4)\n\nWe know e and sigma. we want to solve for t1, temp of black shirt (or white shirt, solving the eq a second time). We can make an educated guess about solar Flux (q) and t2 (ambient temp)\n\nI'm taking a poop and I'm almost done so someone else can take it from here :)",
"Mechanical Engineer here\n\nRadiation is absorbed by black a lot better than white. The way it is measured is by the absorpion constant which varies from 1 being an ideal blackbody (perfect but non existent in real life) to 0 being a perfect reflector. \n\n[The Engineering Toolbox](_URL_0_) has generalized coefficients by color, suggesting a white smooth surface would be between 0.25-0.40. We can assume 0.40 because a T-shirt isn't a smooth surface.\n\nBlack is 0.9 or higher, so it would absorb twice as much radiation than a white shirt. As such, you would get hot twice as fast wearing a black shirt than if you were wearing a white shirt. This is only if you are in the sun, though, as ambient light doesn't really have much infrared heat associated with it.\n\nTheoretically, that means that a black person's skin will be twice as hot as a white person's skin if they were both perfectly black and perfectly white, respectively. That doesn't necessarily mean they will actually feel hotter though, but their skin will feel much hotter to the touch. Once again, this is in direct sunlight\n\nSomething interesting about heat transfer, though. If you wear a baggy shirt you will be hotter than if you wear a really tight shirt, regardless. A loose shirt will trap hot air under your body and serve as insulation. A tight shirt won't trap hot air, and as such the heat is transferred to your body directly through radiation, and it leaves through convection. A black shirt won't necessarily make you hotter, but the shirt will be much hotter. The bagginess and thickness of the shirt are far more useful in determining how hot you will be.\n\nTL;DR: if you werar a black shirt, it will be twice as hot as a white shirt. However, the heat has to transfer from the shirt to your body, so a baggy shirt will make you much hotter than a tight shirt, regardless of color",
"For black skin, it's been explained to me that it's like painting a greenhouse black. Sure, the outside gets hotter but it means the light doesn't penetrate and heat up the inside. Similarly, light gets through several layers of white skin and heats up the inner layers. Having black skin stops the light in the outer layers which lets you shed the heat more quickly. ",
"So, a shirt that's white on the outside and black on the inside seems to be the coolest. You guys watch me kill it on Shark Tank."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[
"http://www.engineeringtoolbox.com/solar-radiation-absorbed-materials-d_1568.html"
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] |
||
7p6adc
|
if both lsd and psychedelic mushrooms use psilocybin then why does one give you an 'energizing' experience and the other gives a more 'relaxing' experience
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7p6adc/eli5_if_both_lsd_and_psychedelic_mushrooms_use/
|
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"LSD is definitely not a party drug. Some people may enjoy it that way, but overall that is not true. Usually you want to be by yourself or with a couple of close friends. Going to a party on it is a terrible idea.\n\nThe trip from both is extremely similar. I would say LSD feels “cleaner” and is much more enjoyable, but it’s not really possible to explain if you haven’t done both. I’ve never had an enjoyable trip on mushrooms, but have always had great ones on acid.\n\nLSD also does not have psilocibin in it, it’s a chemical compound derived from ergot, a different fungus. The effects are very similar but they are completely different drugs.\n\nLSD is not “energizing”, and shrooms are definitely not “relaxing”. It’s really not possible to explain the nuance if you haven’t tried at least one of them.",
"They aren't the same chemical. Only mushrooms are/use psilocybin. LSD is a man made chemical called Lysergic acid Diethly amide (aka \"acid\"). They're both hallucinogens, but act on the brain and body in different ways. However, both have therapeutic and recreational uses under the right conditions. ",
"They're not both psilocybin. LSD is the name of the chemical. It's short for Lysergic Acid Deythlamide, chemical formula C20H25N3O. Psylocybin and psilocin, the 2 psychoactive compounds found in hallucinogenic mushrooms are totally different chemicals."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
9udrhe
|
what are the amino acids? and what do they do to the body? (simple answers cause i’m a noob)
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9udrhe/eli5_what_are_the_amino_acids_and_what_do_they_do/
|
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"text": [
"Amino acids are what proteins are made out of. Your body uses proteins for basically every function it has. The amount and order of the amino acids determine what kind of protein it is and what it does. ",
"Amino acids are the building blocks of proteins. Imagine amino acids like lego blocks, you can assemble them into any shape and size.\n\nAmino acids are all identical, except for a single “side group”. This side group can be a single hydrogen, a complex carbon chain, some nitrogen groups, etc etc. These give the amino acids different properties, which gives the proteins a function.\n\nAny protein you eat will be broken down into its base amino acid components. It doesn’t matter if you eat chicken, peas, beef or mushrooms, you will still get the same amino acids, which your body can use to make any protein. The lego structure will be split into individual blocks, which your body will assemble into functional proteins.\n\nEating “collagen protein” for smooth skin doesn’t work, Nor eating “special proteins” for some magic purpose. In fact, overeating one single source of protein will harm you. Some plants like wheat don’t have the same ratio of proteins as humans, so if you only ate wheat you would be short of some amino acids. It’s like disassembling a black lego boat and expecting to build a blue sphere - impossible.",
"Think of it like building materials. You cells use the amino acids as material for building and repairing your body. If your body does not have the amino acids that it needs, it can't build and maintains anything that uses it. Just like if you were building a brick house and ran out of bricks, you'd have to stop building the house until you go more bricks. This would be everything from recovering injuries, replacing work out cells, building muscles, or just maintaining general health.",
"It's like if your muscles were made out of lego, the small pieces of lego would be amino acids. The large piece would be protein.",
"Amino acids are like a toy roller coaster set. You can link them together to make bumps and loops and contort them into all sorts of ways. Amino acids have a singular, common backbone, which are linked together through peptide bonds, and is like the track of the roller coaster. The entire roller coaster is the protein. And... that's kind of where that analogy ends. \n\nOn this backbone you will have a bunch of different R groups, which are just variable parts that jut off of the backbone. This R group determines what amino acid you have. It can be as simple as a singular hydrogen in glycine, or something like methionine has a sulfur on the end and allows that amino acid to bond covalently with other methionines to strongly joint two different parts of the track together, or the R group can be positively charged, negatively charged, uncharged, aromatic, or even bond back onto the backbone like in proline and cause the entire track to get a kink in its structure. \n\nDepending on the order these pieces of the track are bound together will change how the protein that results will function. For example, an enzyme (a type of protein that catalyzes reactions) may use it's positive amino acids to hold the negative parts of a molecule in place, the negative amino acids to hold the positive parts, and then another section that actually catalyzes the reaction. \n\nThe endoplasmic reticulum (an organelle) will fold the protein makes sure that the track is in the shape so that the critical parts of the track are in the correct place. If it's not in that shape, the protein can't function. If it gets too hot (or if it's too acidic or alkaline) the protein can unfold, and possibly be unable to get its shape back no longer function, and that's called denaturing. \n\nProteins are kind of the working unit for cells. They do an absolutely mind boggling amount of tasks, from signal transmission, to movement, to being a pathway from in and out of the cell, to metabolic functions, to providing structure, etc. If there's something that's done by the cell, it's likely a protein (made up of amino acids) carrying it out. ",
"Ok, this one is DEFINITELY someone's homework. (however if I don't answer the question they delete my post, so: they are what make up proteins)",
"Amino acids are the legos your body uses to make proteins.\n\nProteins are the legos your body uses to make little molecular machines that control your metabolism and whatnot."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[]
] |
||
3f64vx
|
why do people on reddit justify piracy of entertainment, just because they don't have easy access to the content?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3f64vx/eli5_why_do_people_on_reddit_justify_piracy_of/
|
{
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"The content creators only lose money if they lose a sale. If you download something you never would have paid for there is no loss to the legal owners of the content. ",
" > The whole \"if only I could get this in a way that is super easy for me, I wouldn't steal it,\" seems like complete bullshit.\n\nI used to pirate a lot; almost all entertainment I consumed came from torrents. Yet over the past five years or so I've been converted to Steam/Netflix/Spotify/etc. They introduced services that made things super easy and generally cheaper to get hold of.\n\nBefore I would have to go into a games shop and pay fairly significant money even for pre-owned versions of older games. Now Steam offer instant downloads with big discounts for older games. I haven't pirated a game in years.\n\nBefore Netflix, if you wanted to watch an old TV series you'd have to buy a fuck ton of DVDs which cost a lot of money. Even if the price was right, I hate cluttering up my house with things like DVDs and CDs. Torrents were so so so far ahead of the game, I wasn't even tempted to buy legit. \n\nNow, I'm not trying to convince you that my piracy should be deemed acceptable; that sort of debate is often a waste of time. Everyone has their own personal ethics on it. What I'm trying to say here is that just because you don't believe in my reasoning yourself, saying it's complete bullshit is wrong because there are people like me for whom it is absolutely the truth, whether you believe them or not. If not wanting to pay for stuff was the sole reason for piracy, I'd still be doing it."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1hlmmk
|
why when it's 'damp' old people feel it in their bones...
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1hlmmk/eli5_why_when_its_damp_old_people_feel_it_in/
|
{
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"text": [
"When bad weather roles in it tends to come with a lower barometric pressure (lower air pressure). \n\nThis affects how much pressure your body is being subjected to.\n\nWhen there is lower barometric pressure your tissues are allowed to expand (for instance feeling that your joints are swollen or that there is more water retention).\n\nSometimes when this expansion happens some of the liquids that are supposed to be in your body veins and lymph vessels leak out, putting the enervation of our joints under pressure, hence the dull pain that comes with it.\n\nI think it is a controversial issue. This is the best explanation I have for it. "
]
}
|
[] |
[] |
[
[]
] |
||
1ch0ul
|
What was the best year in human history?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1ch0ul/what_was_the_best_year_in_human_history/
|
{
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"text": [
"This sounds like a \"polltype question\" which is not appropriate for askhistorians. sorry."
]
}
|
[] |
[] |
[
[]
] |
||
6o87mq
|
Why is the Mandlebrot set generated on the complex plane?
|
When iteratively calculating the Mandlebrot set I fail to see why using imaginary numbers is useful. Where does the fact i^2 = -1 is relevant? Is the complex plane used only so the mechanics of a + bi work? meaning a+b can't be added and represent the coordinates in a plane?
|
askscience
|
https://www.reddit.com/r/askscience/comments/6o87mq/why_is_the_mandlebrot_set_generated_on_the/
|
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"text": [
"You necessarily use the multiplicative structure of the complex numbers to construct it. If we write f(z;c)=z^(2)+c, then this function is evaluated explicitly through the arithmetic of the complex numbers. The Mandelbrot set is defined to be the complex numbers c so that repeatedly applying f(z;c) to z=0 does not go out towards infinity. To write this without complex numbers, we'd have to write this as:\n\n* F(x,y;a,b) = (x^(2)-y^(2)+a, 2xy+b)\n\nwhich is more clunky. Additionally, it is important for the study of the function f(z;c) is a \"Holomorphic\" function, which means that it is differentiable as a function of complex numbers. These are all super nice functions, and it's really great when you get to work with them. Overall, working on the complex plane is a lot nicer than working in just R^(2), because you have a bunch more tools at your disposal and a lot of very nice theory to fall back on. You would need a specific reason *not* to work on the complex plane."
]
}
|
[] |
[] |
[
[]
] |
|
69o4tj
|
Ottoman Historians: Would Ottomans place slaves purchased from the transatlantic slave route as Janissaries?
|
I teach AP World, but there are some questions that I wasn't exposed to in college or the material I teach with, so this question came up today at my morning tutoring.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/69o4tj/ottoman_historians_would_ottomans_place_slaves/
|
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"text": [
"I've never read anything suggesting that they were. The primary method of recruiting jannisaries during its period as a slave-based institution was through the [devshirme](_URL_0_) which recruited from a quota of Christian boys, mostly from the Balkans.\n\nAs the devshirme declined, it was replaced by a system of free-born recruitment of local muslims in garrison or hereditary recruitment from the askari (military) class."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Devshirme"
]
] |
|
186btj
|
why the celsius to fahrenheit conversion is what it is.
|
So, I get that to convert from C to F it's °C x 9/5 + 32 = °F. But **Why** is it that?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/186btj/eli5_why_the_celsius_to_fahrenheit_conversion_is/
|
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"Because it's how the math works out between the two scales. Fahrenheit was originally created with the freezing point of water at 32 degrees and the boiling point at 212 -- don't ask why, they're arbitrary, except that they're 180 F degrees apart. Maybe it had something to do with how evenly divisible that number is over many integers -- 2, 3, 4, 5, 6, 9, 10, 12 being very important ones.\n\nThe Celsius scale was set with the freezing point of water at 0 and the boiling point at 100, so they're 100 degrees apart. Now, what's 180 over 100? 9/5. What's the difference between the starting point of the two scales? 32 F degrees. Voila, you get that conversion equation.",
"Celsius is set up so that water freezes at 0 degrees and water boils at 100 degrees. Fahrenheit is set with water freezing at 32 degrees and boiling at 212 degrees.\n\nTo go from Celsius to Fahrenheit, there are two things to take into account: where zero is and how big a \"degree\"is. Since 0 Celsius is 32 Fahrenheit, you add 32. Then, you multiply by 9/5 because each Celsius degree is 9/5s as big as a Fahrenheit degree. You can see this by taking the boiling to freezing temperature difference in Fahrenheit (212-32=180) and dividing it by the boiling to freezing difference for Celsius (100-0=100). The result is 180/100, which reduces to 9/5!",
"[Because Farenheit was a nutter, basically](_URL_0_). In Celsius, water freezes at zero, water boils at 100, everything else is in-between. In Farenheit, **brine** freezes at 0, water freezes at 32, and (originally) average blood temperature was 3x the freezing point of water (96). \n\nThis is just speculation, but I shouldn't wonder if Farenheit picked a 0 that was less than water-freezing temperature because that way you could fill a thermometer with specially salt water and measure how cold it was even if it was cold enough to snow. "
]
}
|
[] |
[] |
[
[],
[],
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"http://en.wikipedia.org/wiki/Fahrenheit#History"
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|
5x68r3
|
what exactly did sessions do, and why is is such a huge deal?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5x68r3/eli5_what_exactly_did_sessions_do_and_why_is_is/
|
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"He was in communication with Russia during a time when Russia was suspected of tampering with our election. While this is not illegal, Sessions lied about this contact while under oath which IS illegal.",
"He had two meetings with the Russian Ambassador to the United States during the Trump campaign for the Presidency. This in and of itself may not be of significance. However, he did not disclose those under sworn testimony to Senator Al Franken, instead saying, \" I didn't have — did not have communications with the Russians.\" This could potentially constitute perjury, although his defense so far appears to be that these meetings fell within his (reasonably possible) job duties as a US Senator on the Armed Services committee and so he did not mention them as they were not relevant to the Trump campaign for the Presidency.\n\nHowever, whether they are perjury or not, given the intense suspicious currently hovering over the administration regarding communications with Russia, they present yet another uncomfortable stumbling block for the administration in avoiding at least giving the appearance of being compromised with more Russian influence than many consider proper. \n\n",
"Sessions was asked \"did anyone affiliated with the Trump campaign have any contact with russia during the election?\" \n \nSessions said no, except he was affiliated with the Trump campaign and did have contact with russia during the election. \n \n*Why* he was contacting russia isn't the problem. The problem is that he lied under oath to congress."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
87gmnd
|
why|how do we make reddit bots that remove post automatically?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/87gmnd/eli5_whyhow_do_we_make_reddit_bots_that_remove/
|
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"As to why, we make them because they are effective at combating spam and ensuring a level of quality without requiring a human to operate. A bot only requires a human to take a look at appeals and complaints, ie. to correct any false positives or negatives, instead of a human having to manually go through all posts.\n\nFor how, a bot is given certain triggers (for example, common words or features in spam messages) that it looks for. Based on these triggers, the bot decides if a post is spam or otherwise against the rules, and if it is, removes it. Of course, a bot requires a human backup, as it may have false positives and false negatives, but a bot vastly reduces the work load on admins in a subreddit."
]
}
|
[] |
[] |
[
[]
] |
||
2vohx0
|
if symptoms of being sick (mucous, sore throat, fatigue) are immune system responses, what does the cold virus actually do?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2vohx0/eli5_if_symptoms_of_being_sick_mucous_sore_throat/
|
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"It invades cells in your upper respiratory tract and reproduces inside of them. Viruses utilize special mechanisms to commandeer the machinery inside of your cells and turn them into little virus factories. Eventually, these cells will burst and release millions of viruses which will go and infect other cells. More serious viruses, such as Ebola, can do a lot more damage because they can evade the immune system and continue to reproduce inside your cells, which will eventually kill you if your immune system cannot stop it. ",
"I'm not well versed enough on the actual mechanics behind viral reproduction to provide a long form answer, but briefly, the virus takes over and destroys cells in the affected areas.\n\nThis prevents the affected cells from performing their normal jobs.",
"While your immune system is fighting them, pretty much nothing. However, if they were allowed to keep reproducing without a fight, then they would just keep killing off cells at faster and faster rates, eventually preventing vital functions from working and killing you.",
"just came across this link this morning...\n\n_URL_0_",
"I am not a doctor or a biologist but without the immune response I am assuming you would experience similar symptoms as someone with Necrotizing Fasciitis. \n\n _URL_0_\n\nBasically the infection would eat or kill healthy cells and spread causing bleeding, weakness, massive inflammation, pain, and eventually death. ",
"People almost never die of the common cold. Instead, they die of other opportunistic diseases that take advantage of a weakened body (from fighting the virus and rebuilding things that get destroyed in the crossfire) to set up shop. From there, the sky is the limit in terms of how many fascinating ways you can die.\n\nIf there were no other contenders and no response to the virus, you would slowly loose cell function via lack of vital proteins from overloading of protein synthesis pathways with virus RNA, your cell populations would decrease from necrosis by lysing, and you'd eventually die of systemic organ failure. As I stated before though, this never happens in reality; before the cold virus gets to that point, you'll either recover, or die of another disease.\n\nNow, what if the common cold were the only disease present, and it was winning, but your system was not completely forgetting to do the things that usually accompany a viral infection? This is ... an interesting situation. It is theoretically possible for a person to die of something like viral induced meningitis (a condition in which inflammation around the brain and spinal cord causes increased pressure in those areas). However both its onset and result in fatality are very unlikely, and neither this nor any other direct fatal result of a common cold infection has been documented in an adult human in reality as far as I know.",
"Most basic response:\n\n1. squats in your cells\n1. steals your food\n1. makes babies\n1. your cells die of starvation and the virus' fecal mater (RNA)",
"Well since we are on the topic of colds, ELI5 why I am getting a reoccurring cold every two weeks it seems? ",
"When people with AIDS get a cold, they have a higher risk of pneumonia. It stands to reason that an asymptomatic cold, that is to say a cold that does not get fought by the immune system at the spot of infection, would eventually cause pneumonia. Then you'd be in serious trouble. \n\nTLDR; Pneumonia ",
"Thanks for the answers everybody, but can can I politely ask someone to address the issue of snot? How the hell does me being a snot factory help my immune system fight off the rhinovirus? \n\nDoesn't it seem more likely that me being a snot factory is for the benefit of the virus and not me? Me gets sick, me snots all over the fucking place, snot gets on other people, other people become snot factories, and the cycle continues. Right? \n\nEdit: Also I am sick now, and every time I get sick, I want to make a shirt that just says \"Snot's Not Okay!\" ",
"Piggybacking on this, I have a cold right now. Why do I wake up with a dry nose/no symptoms but then within 30 minutes it all comes back?",
"Why don't we become immune to the common cold after having getting it? Why isn't their a vaccine against it?",
"Long answer short, the cold virus turns your cells into factories that reproduce itself. It does this because the virus has no other way to replicate other than using another living thing (in this case your cells) in order to reproduce. The immune responses that you feel (mucous, sore throat, fatigue) are all symptoms of your body ridding itself of the virus. It does this by the only way that is viable which is killing its own cells already infected by the virus. The symptoms you feel from the cold are from the cell death and the subsequent ways your body deals with the cell death associated with your body killing its own infected cells. ",
"Once introduced, the virus will enter one of your cells, usually near the point of entry (nose, mouth, throat). The virus will then commandeer your cell's functions and materials necessary to replicate itself. Your cell is essentially the virus's host. Once the baby viruses are ready to be born, your cell will lyse (=dead cell). The newborn viruses will then attack neighboring cells. This will continue and without your immune system, the virus can and will keep attacking and killing cells, until you die. \n\nWhat your immune system does to combat the attack of a virus is two-fold. One is a general search and destroy of cells that have been flagged as under siege. This causes the sore throat and the mucus is the byproduct as an attempt to flush out debris from the battle. This continues until the second and more specific line of defense is found (the body's specific antibody for the virus). The antibody is then replicated and used to fight the virus until the war is won. ",
"The human body's primary method of defeating viruses, aside from the white blood cells, are quarantine and cooking. The fatigue comes from the bones, the body diverts resources into producing white blood cells.\n\nThe sore throat is caused by the virus damaging the skin and thinning it.\n\nThe mucous is the body sending white blood cells out of the blood stream in the vector, a suicide mission.\n\nSpot creation: By sealing an area off and then raising the temperature, one encourages viral growth within a closed system, leaving the virus forced to contend with an abundance of virus particles and a lack of food sources but a key-lock mucous, which is essentially a red herring designed to trick the virus into suicide.\n\nEventually the virus is going to run out of sustenance and die within a closed, inhospitable area, or kill itself trying to inject itself into a red herring.\n\nWhilst it is doing this, the body pumps white blood cells into the area, to attack and analyse the virus, looking for weaknesses.\n\nOnce a weakness is found, the virus is then attacked to extinction in all places where it occurs and the pus filled quarantine area is then reabsorbed slowly, the antibodies are then cycled to ensure that no further outbreaks occur. The trouble is; sometimes the pressure from the quarantine can become so high that it mechanically affects other parts of the body. In some cases it is just a small painful abscess, in others, the abscess can be massive.\n\nThis is why it is really important, not to pop spots because if the body hasn't finished killing the intruder, you will spread it everywhere, or if you do have to lance it because of say, inter-cranial pressure or excessive pain. Make sure to lance it and extract the core with a syringe made of silver (as silver has anti-bacterial/viral properties) or surgical steel that is coated with a minor disinfectant. With spots on the skin, it is really bad idea to squeeze them without coating the skin with a disinfectant, because they can spread everywhere really quickly.",
"This entire thread makes me want to play plague Inc again. ",
"You have to look at viruses as the little hijackers they are. They have no method of reproduction so they hijack a cell to do it for them. Think of a virus as a terrorist, who decides to visit your a Kinkos (your cell). The virus will then hijack your printers (ribosomes) into copying the genetic sequence of the virus. Once your Kinkos is filled with the virus, they either can either bud out through the membrane (lysogenic) or blow up the Kinkos (lytic cycle) to spread the new viruses created. Many will be of those will be destroyed by the T cells and macrophages but some will escape notice or implant themselves within other cells, repeating the above cycle. This is all I remember from high school biology.",
"The virus wipes out the epithelial layer of your throat and this allows for bacteria (which are always present) to establish themselves. This is why you are most contagious before you feel anything. The virus will burn itself out and then as the bacteria come on you will feel the bad symptoms. ",
"It seems weird a virus exists only to kill the host that feeds it.",
"Running from the white blood cell cops, haven't you seen Osmosis Jones?!?!?!",
"Man, I once posted this on a reddit thread and got down voted to hell and told I was stupid. I just don't get it. It's like the first reply to a submission determines all the rest of the comments. ",
"Basically, a virus hijacks the specific cells they infect and turns them into virus factories. Im the case of a virus like the common cold, which does not have a membrane envelope, the virus eventually burst the cells releasing lits of new virus particles into the tissue.\nThe infected cells produce molecules called interferons, which try to shut down the virus and also cause neighboring cells to be more resistant to viral infection. These interferons are responsible for the general feeling of lousiness when you are sick.\nIf a virus is able to replicate unchecked, it will destroy the tissue where it is and keep spreading. The real trouble is if the virus gets into the blood and is able to spread to the rest of the body. Containing the virus is another aspect of the body's immune respone.",
"When your immune system attacks the cold virus, it kills it, but it also attacks you as collateral damage and inflammation occurs.",
"So, there's this country (you), whose economy (health) is based largely on car factories (the cells that make up your body's tissues). Selling cars (creating things like enzymes, and transporting them) brings in the resources that the country needs to prosper.\n\nA foreign crime syndicate using brand-new robot soldiers (viruses... work with me here) moves into a major industrial area (lungs) in this country, and its robot soldiers attack the car factories. If they succeed, they will use the materials that the factories have on hand to make more robot soldiers--collapsing the economy (killing you) in the process. They don't care, there are other countries (people who are not you) to attack with their now bolstered numbers.\n\nThis country is not defenseless, but war is never easy. The factories that are under attack start making guns, instead of cars, to help fight off the invading robots. They also call their friends at other factories in the area, and *those* factories start making guns, instead of cars, in preparation. The factories are still working at this point, but they're doing something other than what they usually do--at least in part--and what they usually do is vital to the economy. \n\nThere is a military. However, those people need to be paid (provided resources). Some of this is already covered in the annual budget, but there will be casualties--as well as damaged equipment needing to be replaced or repaired, and no standing military is ever enough to fight off an invasion--if they were, there'd be nothing for them to do most of the time. \n\nSo, the already wounded economy is further stretched to accommodate the recruitment of new soldiers and the manufacturing of new equipment, as well as the repair of any damage to the country's infrastructure. Lost soldiers will have to be replaced through additional births, which means that the civilian jobs once occupied by now deceased individuals (the ones who signed up to fight the robot army) go unoccupied in the meantime (thankfully, within your body, this happens pretty quickly on the small scale, but large-scale damage--like a war-torn countryside--can take a very long time to heal). Everyone needs to work overtime, people are tired and worn out. Everyday wear and tear takes a greater toll than before. Raw materials are lacking. \n\nCriminals (everyday viral exposure), as is common in war-time, take the opportunity to expand their own enterprises (Dick Cheney) at a cost to the legitimate economy--normal, everyday threats are harder to deal with while the country is recuperating.",
"Hijack over the machinery of your body for it's own reproduction, just ask anyone who doesn't have an immune system, i.e someone with AIDS. The death for immunocompromised patients is essentially caused by the pathogens that were normally kept at bay by so many layers of defenses, and now decided to use the nutrients and resources in our cells for themselves. \n\nEdit: grammar",
"There's plenty of theories abound that the virus is smarter than most people credit it for. The theory goes that the virus infects other hosts because of the immune system responses helps it to reproduce. In other words, because you're sneezing and have a runny nose, you're more likely to infect someone else. Essentially using a person's immune responses as its reproductive system to infect another host. It supposedly intentionally selects your lungs and nasal passages because that's the easiest way for you to transmit it elsewhere.\n\nSame goes with cholera. People in 3rd world countries get cholera because they drink water from natural sources where other people have cholera and had diarrhea. In turn, you now have diarrhea and handle your business at the local creek, which is also the natural water source for some community downstream.\n\nTLDR: It's intentional, you're not just collateral damage.",
"As simply as I can\n\nHijack cells and kills them. Your immune system is trying to save you because a virus doesn't care what cells they hijack. \n\nA virus needs a living cell to reproduce. ",
"The virus gets into some cells, makes copies of itself in an effort to make more virus to spread to more people. In the meantime, some immune cells get pissed off with all this silliness and they go all \"Oh no you didn't\" on the virus virus, meanwhile messing with your sinuses.",
"The virus itself will eventually turn you into a living meat patty. Trust me, I'm a student.",
"The best way to answer your question is to consider what respiratory viruses would do in the absence of an immune system. Coincidentally, there is a population that has been studied extensively that fits this criteria--the immunocompromised population. \n\n_URL_0_"
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[] |
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[],
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]
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||
40i4be
|
when you accidentally close a book, and then try to get back on the same page, how is it that you can "randomly" open the book and be +/- a few pages of the page you were on?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/40i4be/eli5_when_you_accidentally_close_a_book_and_then/
|
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"You had some idea about where you were. You tried to open it there. The book also has a memory in that it was opened to a page. The bindings and paper had shifted.",
"1. you've stretched and not re-compacted the binding in that spot. It's the last place you held open. Further, the pages just before the spot you're on have all been recently stretched and had the least amount of time to be re-compressed.\n\n2. you know pretty darn well where you are approximately. So...there is a smidge of confirmation bias here - you're not really finding the page within the entire book, you're finding it within a sub-section that you know to be pretty close. \n\nedit: pour spallinj"
]
}
|
[] |
[] |
[
[],
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||
6sbqab
|
why do beavers make dams?
|
Do they live in them? Are there little beaver apartments inside? Also, are beavers just fat otters?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6sbqab/eli5_why_do_beavers_make_dams/
|
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"Beavers build lodges next to streams to live in. \nThe living spaces are high and the entrances are low. \nThey build dams so the entrances to the lodges become underwater while the living spaces stay above water.. \nSince the entrance is underwater things that can't swim can't get in, since the living spaces are above water, things that can only swim can't get in. \n[Here's a picture of both the dam and the lodge with a dachshund for scale.](_URL_0_) \nNote how the lodge is entirely surrounded by water, if the living space was in the dam, things that can't swim could walk along the dam to the living space. \n \nSo yes and no, the little beaver apartment is upstream from the dam, but not inside the dam.\n",
"Dams raise water level which kills trees and serves two purposes. 1. Dead trees can thus be used to build beaver houses. 2. Beavers thrive In a flooded wetland and most of their food comes not from flowing rivers but dammed up wetlands. ",
" > Beavers and otters might occupy the same sorts of aquatic habitats, and their ranges often overlap, but they are completely different animals.\n\n > They have different bodies, different diets and different roles in the ecosystem.\n\n > Otters are carnivores, living on fish, amphibians, aquatic reptiles and invertebrates and often taking the role of top predator in freshwater ecosystems.\n\n > Beavers, on the other hand, are herbivores, eating mostly leaves, roots, bark and twigs.\n\n[Source](_URL_0_)",
"Beavers build dams to flood an area, which allows them to move from their lodge to their feeding areas by swimming through water instead of walking on land where they are more vulnerable to predators. Beavers predominately eat willow, cottonwood and aspen trees, specifically the tasty and nutritious cambium layer under the bark. These trees grow in the riparian zone (along rivers, lakes and streams) where beavers mostly hang out. \n\nA study was conducted that determined that the instinct to build dams is triggered by the sound of running water. Beavers were left in an empty room with a pile of sticks, and the sound of water was played from different directions, and the beavers would move the pile of sticks to where they heard the water. \n\nBeaver created ponds provide habitat for a lot of other animals, from birds to big game, and provide crucial ecosystem services that greatly benefit people too. Their ponds store water (like reservoirs) and make it available later in the year when it's needed most. They also filter the water, and some of it seeps into the ground and recharges aquifers. The ponds Eventually fill with sediment and become beautiful meadows. ",
"Canadian here. Lots of good info here, but what has been missed is a discussion about *winter*. Beavers build dams and lodges. Dams just control water level, but lodges are dams they live in. As stated, the entrance to the dam is below the waterline. The tricky thing beavers manage is the entrance must be below the level of the *ice* that forms on top of the flooded area. A deep pond is better, but harder to create. The entrance must be able to be open all winter because the beaver will store food (young trees and stuff) below the waterline. I have seen lodges with dead beavers...the water level got messed up too late in the year, and caused the ice to form too low."
]
}
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[] |
[] |
[
[
"https://celebritydachshund.files.wordpress.com/2012/06/beaver-dam-lodge-pond.jpg"
],
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"http://animals.mom.me/difference-between-otters-beavers-3101.html"
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[],
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] |
|
2d50le
|
the importance of honey bees in our (daily) life and why they are dying off so rapidly
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2d50le/eli5_the_importance_of_honey_bees_in_our_daily/
|
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"Basically, it's not just honey bees, it's bees in general. Without bees, most plants would not be able to pollinate and such not able to bear fruit. They are dying of because of pollution, extermination and loss of habitat",
"You've probably seen it on the news lately because one type of pesticide, a relatively new one called neonicitinoids, has been identified as a possible cause of colony collapse disorder - the sudden mass die off of hives. There's also the increase in mites that infect bees and possibly malnutrition.\n\nBees are important because they pollinate so many crops. Hives are rented from beekeepers in the spring so flowering plants are pollinated so they'll produce fruit. But this movement of hives from site to site as they are rented by different farmers exposes bees to a variety of chemicals and bee diseases, any of which (or any combination of which) may be the reason they're dying.",
"They are dying because of a number of factors, largest ones I believe to be pesticides and the honey industry - we take their natural food and replace it with glucose, and long term this doesn't do them any good. ",
"This is a huge issue. \n\nIt starts with the relatively new use of [Neonicotinoid](_URL_1_) class of insecticides. These insecticides were supposed to get rid of wide variety of insects/pests. And in their general application most users DO stay away from Bees as bees are so, so critical in our food chain.\n\nWhat apparently is happening, scientists are still putting together the pieces here but [the story looks pretty strong at this point](_URL_0_), is that the bees are receiving a mild dose of the insecticide. That affects their ability to 1) reliably get back to the hive and 2) survive the winters successfully.\n\nLong story short, this class of insecticides is critical to get out of the ecological system. If the bees go you can say goodbye to all sorts of nuts, fruits, vegetables and for sure, honey.\n\nWe keep one hive of bees on our small farm. That hive swarmed (left) this Spring and we have no cherries this year and our apple trees are pathetic for production.\n\nI can't urge you enough to stay up to date on this issue and input your two cents where and when you can. Bees are too critical to lose.",
"[SciShow to the rescue!](_URL_0_)",
"It's actually more likely the veroa mite. Reddit loves to jump all over pesticides and while they are harmful if applied incorrectly, there is plenty of evidence that CCD is caused by these mites. For example no veroa mites heavy neonicotinoid use in Australia limited CCD.\nEdit: us department of ag's own report _URL_0_",
"The commercial method of raising food crops in a monoculture environment depends heavily on hives of European honey bees being relocated to the area just as the flowers are ready for pollination. Native bees aren't as suited to this because they don't create such large colonies. Some smaller growers take steps to attract natives pollinators by planting flowers near the crops, but commercial growers probably see this as a waste of space. \n\nDisclaimer: this is all from memory from an article I read like 2 years ago.",
"Honeybees are important because honey is delicious.\n\nThey're dying off for a variety of reasons including:\n\n* Urban beekeepers.\n** I'm seeking a wild swarm to put behind my ginormous fruiting hedge and mini-orchard, which will attract butterflies, hoverflies, bees, wasps, more bees, oh god there are six hundred varieties of bees here, yellow jackets, why are there Japanese hornets on the east coast, and hummingbirds.\n** By contrast, many hippies in San Francisco are placing bees on roofs, but no flowers: they suck down all the nectar, and then wild and domesticated colonies starve en masse. Further, many beekeepers import bees without the genetic adaptations to the local climate, parasites, and diseases; these swarm, send out drones, and otherwise spread their defective genetics, weakening local populations.\n* Pesticides, to some degree.\n* Pollination services. Bees carted from place to place pick up non-native diseases and parasites, and then move to another place to infect the local population.\n\n",
"The honey bees that have experienced colony collapse disorder have all been colonized bees that reside in moveable hives that are transported from farm to farm in order to pollinate certain crops on a massive scale. This is most commonly seen in California and the almond plants which greatly depend on bees pollination to flourish, using this technique caused crop yields to greatly improve. \nThese colonized bees are forced to live very close to each other along with the other boxes and boxes of colonized bees. These tight living quarters along with bee's poor immune system cause sickness to spread very easily. Resulting in mites and other diseases to spread and kill off the bees, which results in the colonies collapse. \n\n ",
"The honeybee is a larger part of the agricultural landscape. These bees are used to pollinate many different types of crops and this results in much larger fruit sets than if there were no bees. From almonds to peaches to berries to apples to pears and cherries and melons and squash and the list goes on and on. When you stand in the produce isle, about 30% of the fruits and veggies are a result of bee pollination. \n\nThese bees are also used in oilseed production. So your French fries and anything that is fried usually is fried up of some type of vegetable oil like canola oil. This oilseed needs large amounts of pollinators and no more bees means no more oilseed.\n\nAs for why they are dying off:\n\nIn the 1980's a parasitic mite (Verroa destructor) transfered from the Asian honey bee to the western honey bee, and has since spread around the world. This mite reproduces in the brood cell and greatly reduces the vitality of the hive, leaving it much more vulnerable to diseases and viruses. Beekeepers use insecticides to control the mite levels but throughout the last 30 years some have developed resistance to the insecticides and as such there is only one insecticide that is effective that is used. It is only a matter of time until there is full spread resistance to this miteacide as well. Organic acids are also used also to control the mite but they are more difficult, costly and time consuming and are not used in large scale operations for the most part.\n\nThere are also many chemical poisonings resulting in the application of insecticide or herbicide to crops that the bees forage on, and as the theory goes, an accumulation of sublethal doses eventually causing a failure to thrive and colony collapse. \n\nThe type of crops planted in agricultural areas have also changed in the last hundred years. Where there used to be acres of grassland with wild flowers and large hay fields of alfalfa, now it is more common for a large percent of this forage to he planted in corn which provides very little for bees.\n\nThe economics of beekeeping is also a factor. There is cheap honey produced elsewhere in the world that can make it difficult for honey producers in North America to compete economically. The cost of operating a honey producing operation, like most businesses, is going up. And many beekeepers cannot make a great return resulting in people leaving the business. We could use some more young people if you don't mind getting a sting from time to time. \n\nSource: junior beekeeper man",
"Can I buy bees and put colonies around my property to pollinate the fuck out of it?",
"As for the importance of bees independently, bees have a very close co-evolution with many plant species, typically 'modern' plants are mainly evolved to be pollinated by bees, there's also wind pollination (mainly used by grasses *poaceae*), fly, bird, butterfly, bat, beetle, moth and others. Before bees evolved, many plants were pollinated by beetles (but this is limited as most can't fly, limiting distance of pollen travel).\n\nMany flowers are specifically adapted to their chosen pollinator, and suffer reduced pollination when it's not around. Look around outside at flowers and look at their shape, a good example is foxglove, which has evolved to be pollinated by bumble bees - _URL_1_ It's flower is the right shape so the bee has to crawl inside rubbing what ever pollen it has on its body, and also being covered in more from that plant. See those little dots on the petals? They're UV guides so the bee can see and access the flower quicker. If the bee finds the reward quicker it's more likely to return to the plant.\n\nThe bee and the flower's survival strategies have co-evolved to compliment each other. The bee pollinates the flower and recieves the nectar as a reward for its service. The bee has specialised pollen 'baskets' on its back legs to carry more and a long probiscus (tongue) to access the nectar (this also limits other species from nectar robbing as they wont have the right mouth parts - e.g. flies). Bees and flowers are in an evolutionary lock, and loss of either is detrimental to the other. To see how closely some are evolved, look at buzz pollination - where the frequency of the vibrating wings of a specific bee species releases pollen of the plant.\n\nBut why is this important? Surely if the bee goes then other pollinators will take up the slack and we'll just have a few more inbred plants? Yes and no. The main issue is very few plants are generalists and able to be properly pollinated by other species. Flies are more interested in carrion, moths/butterflies have too long legs, so when feeding on plants are far above the pollen.\n\nThis photo shows a good example of the effects of fruit production by different pollination. _URL_0_ On the left, is normal bee pollination, on the other two is hand (by humans) and self pollination.\n\nWithout the bees, we will lose a lot of fruit production, plant genetic variability (making them more susceptible to invasive species and diseases) and some closely evolved species of plant entirely.\n\nAlong with the other points mentioned in this thread. The intensification of farming has affected bees, along with reducing field margins (where wild flowers grow and bees feed and pollinate). The increasing use of nitrate fertilisers increases crop homogeneity - which is great for farming, but again reduces available resources for bees. Invasive species of plant and animal on ecosystems also take their toll.\n\nSource - I'm a BSc Biology student studying this type of stuff for my dissertation.",
"A good article: [Bees and CCD: Myths and Facts](_URL_0_).",
"Biology student here - I spent this summer doing research on this exact problem. There's no one reason for this phenomenon, but there is a lot of literature on contributing and synergistic factors. \n\nTo be brief, pesticides are picked up by foragers in the field, and rub off onto the wax of the hive where it accumulates. Miticides are applied to beehives by the beekeepers, which interact to increase the negative effects of pesticides. Interestingly, *Apis Melliflera*, the commercial honeybee, has 1/3 the normal amount of genetic code that allows for detoxification. \n\nMites (In particular the Varroa mite) suck on the hemolymph (blood) of pupal bees, and an infestation can kill a healthy hive within a few years. They are incredibly hard to detect by normal hive inspection, and commercial beekeepers tend not to use PCR analysis to check their hives. \n\nMonocultured crops cause poor nutrition for the bees - bees need 10 amino acids to grow and survive, and there are very few pollen sources that are rich enough in all 10 for bees to be able to survive off that. Furthermore, feeding off monofloral pollen sources can decrease their immune resistance. \n\nI have sources for these statements but a lot of them are behind paywalls. PM me if you want a PDF of relevant literature!",
"I asked the same question to a bee keeper in NYC and he listed these 4 reasons\n\n1. Almonds. USA produces 80% of the worlds almonds. In the spring, a huge percentage (forget the exact number) of the honey bee population is shipped to Cali where they feed on just almond pollen and nectar for a few weeks, then they get shipped back to where they came from and are very sick and die quickly. He said Kale is very good for you, but if you ate just Kale for several weeks, you would be very sick. \n\n2. Pesticides being sprayed \n\n3. Plants that are genetically modified to have pesticides within the plant, so when the flowers bloom, they are toxic even though they haven't been sprayed.\n\n4. Varroa mites. A parasite that came from Asia, kind of like ticks. They carry viruses and disease and spread it to colonies when they get into a hive. They first were introduced to Ameria in 1987 and there was a huge loss in the bee populaiton that year. ",
"Followup question. Is the link between human extinction and bee extinction justified? That is, if the bees go, we go theory?\n\nThanks."
]
}
|
[] |
[] |
[
[],
[],
[],
[
"http://ento.psu.edu/publications/are-neonicotinoids-killing-bees",
"http://en.wikipedia.org/wiki/Neonicotinoid"
],
[
"http://youtu.be/Zgc5w-xyQa0"
],
[
"http://www.ars.usda.gov/News/docs.htm?docid=15572"
],
[],
[],
[],
[],
[],
[
"http://berkeley.edu/news/media/releases/2006/10/images/pol_strawberry.jpg",
"https://c2.staticflickr.com/8/7305/9125117527_384439bc26_z.jpg"
],
[
"http://www.twipscience.org/news/2014/8/8/bees-and-ccd-myths-and-facts"
],
[],
[],
[]
] |
||
2i4jqo
|
how does wifi keep up with all the signals in the air?
|
I've got one Wifi Access Point, but I've got 10 wireless devices all connected to it. How does it not get stupidly confused with all the signals in the air at the same frequency.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2i4jqo/eli5_how_does_wifi_keep_up_with_all_the_signals/
|
{
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"text": [
"WiFi uses something called CSMA/CA, which is Carrier Sense Multiple Access with Collision Avoidance.\n\nWhat this really means is that it's a system where, although it might seem your device is constantly sending data, it's actually not. There'll be a pause where your laptop stops sending, and then your tablet will jump in for a bit, then that'll pause, and your e-book reader will have a go.\n\nThe way they do this isn't dissimilar to the way you might try to get the attention of the bar staff in a busy pub.\n\nObviously, if they're serving someone else, they're not going to serve me, so I'll check that first. If they are serving someone else, I'll wait a bit. This is exactly what your WiFi device will do - it'll listen to see if the channel is in use, and if it is, it'll wait.\n\nSo then, back in the pub, once the barman is free, I'll try and get their attention. This isn't a classy pub, and so I'll do it by yelling, and seeing if I get a response. As it happens, I yell at the exact same time as someone else, and so the barman has no idea who's just called. Maybe the other customer gets served first, maybe neither of us do. If I don't get a response the first time, I wait for the barman to become free, and then I yell again.\n\nThis time, the barman acknowledges me, and so I can send my data (my data being \"two pints of lager and a packet of crisps, please\").\n\nYour WiFi device is doing pretty much the same thing. It's checking to see if the channel is free. If it's free, it's asking the other device (probably a router) if it can send it data. If it doesn't get a response, it assumes it hasn't been heard, and tries the whole thing again, until it gets a response saying it's OK to send the data.\n\nSo, to go back to the second paragraph, there aren't necessarily loads of signals in the air at the same time. It might seem to you, as a slow human that everything is communicating simultaneously, but in actual fact, all your devices are doing it one at a time, and swapping between each other very, very quickly."
]
}
|
[] |
[] |
[
[]
] |
|
2jvvi2
|
If every human on earth walked east along the equator, would we slow down the rotation of the earth?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2jvvi2/if_every_human_on_earth_walked_east_along_the/
|
{
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"clfz1dm"
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"text": [
"Well, yes, but the effect is completely irrelevant. It also doesn't build up.\n\nLet's idealize a human as a point mass (this is a very good approximation compared to Earth's radius). Your angular momentum is L = r p = r m v, where m is your mass, v is your velocity, and r the distance from the axis of rotation. If you're not walking, the same formula applies, but the velocity is a little bit smaller, namely L' = r m v' where v' is equal to the velocity of Earth's surface.\n\nv' = ω r = 2 pi/24 h * 6400 km = 465 m/s, so even if you walk pretty fast (say, 10 m/s), your own personal angular momentum would only change by a few per cent. Let's say I have a mass of 100 kg and could actually run so quickly, then the difference is about 6x10^9 m^2 kg/s. \n\nAssuming Earth is a sphere, it has a moment of inertia of I = 2/5 M r^2, which gives an angular momentum of L = I ω = 7x10^33 m^2 kg/s (using a mass of 6x10^24 kg). This is 24 orders of magnitude larger than your puny walking effect. Even if you take all 10^10 humans together, it is still 14 orders of magnitude larger and still completely negligible.\n\nI should note that my argument is a little bit circular is I used the assumption that Earth's orbital velocity doesn't change due to your walking in my calculations. This is allowed because itwould be a second-order effect, and therefore would be quadratically smaller."
]
}
|
[] |
[] |
[
[]
] |
||
1sr6m1
|
how come when i sing along with a song i sound awesome but when you take away the vocal track i sound ridiculously horrible?
|
dsfghjkl;'
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1sr6m1/eli5_how_come_when_i_sing_along_with_a_song_i/
|
{
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"ce0l3y8"
],
"score": [
2
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"text": [
"I think your ears are blending the two voices. It also might be that you feel more confident in singing it with the vocals. Two things I do to tell how well I'm really doing: first, gradually decrease the volume of the song, but keep your singing voice the same. Second, take a finger and plug one ear while singing. It helps drown out the outside sound, but still hear your own vocal vibrations. \nI have the same problem too, if you can't tell. XP"
]
}
|
[] |
[] |
[
[]
] |
|
abkmkz
|
Origin of Christmas tree and Christmas lights.
|
During a guided tour of Tallinn, Estonia, the guide told us that the first Christmas tree (a pine tree) was put up in Tallinn by a rowdy group of young merchants from the Black Head Guild. The tree was set on fire and this happened over a few years, until a house burned down, and the city administration banned the burning of the tree, so the next year it was decorated with a bunch of lanterns to give the impression of a burning tree. SinceTallinn/Reval was part of the Hanseatic League, from there it spread to other European/German cities. The guide mentioned that these are verifiable facts, because the Black Head Guild tended to keep good records. Can someone knowledgeable comment on this, please, as I am really hoping that this is true.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/abkmkz/origin_of_christmas_tree_and_christmas_lights/
|
{
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"[This news article of NYT in Dec. 22, 2016](_URL_0_), relates the 'hot debate' between Riga in Latvia and Talinn in Estonia over the historical origin of Christmas tree, so we should take either of their claim with a grain of salt (Just for conformation, I came from neither of two, nor Germany, the third candidate of origin country of Christmas tree). \n\n & nbsp;\n\nAFAIK there has seems to be no recent academic contribution for this topic, it is perhaps useful to turn on checking the qualification of the skeptic 'specialist' interviewed in the news article at first: Dr. Gustav Strenga has wrote his dissertation, titled as '[Remembering the Dead: Collective Memoria in Late Medieval Livonia](_URL_3_)', Ph. D. thesis, submitted to UCL, 2013. \n\n & nbsp;\n\nIn his Ph. D. thesis, he analyzes how the merchant guilds and their confranities of Riga and Reval commemorates their dead by some seasonal rituals, based on the archival (non-printed) sources including Black Head Guild. He has also just authored another article on the liturgical conflict between the Teutonic Order and the Church of Riga, ['Distorted memories and power. Patrons of the Teutonic Order in the fifteenth century prayer of the Livonian branch'. Journal of Baltic Studies ](_URL_5_). DOI: 10.1080/01629778.2018.1511605. So, he is clearly speciallized both in the above-mentioned primary sources as well as in the topic itself. \n\n & nbsp; \n\nWe should turn our attention now why/ how he showed a cautious attitudes toward the connection between the practice of erecting/ burning trees recorded in the guild book of the Black Head Guild and Christmas (tree), mainly based on his argument in [another potcast (Dec. 23, 2016) ](_URL_4_) (apparently inspired by NYT's article): \n\n* The guild members commemorated the festive day by erecting/ burning trees not only in Christmas, but also in other religious holidays like Lents in medieval Livonia (now Baltic countries). So, we cannot prove the exclusive connection between Christmas and the tree in this cases found in medieval Livonian cities.\n* It was the 19th century historians on medieval Livonian merchants that firstly assigned this practice as a direct predecessor of the Christmas tree, not earlier. In other words (the following is my understanding), there was no sources that related the relationship between Christmas and this ritual in Early Modern times (17th and 18th century). \n\nFrom these two evidences, Strenga's answer is 'possible but probably not'. \n\n & nbsp;\n\nNote that the 19th century was a age of National Romanticism, in which the emerging modern [edited]: historiography entangled with sometimes complicated 'national' identity, not only in France and in Germany, but also in the Baltic as well as Scandinavian countries. To give an very famous example, Kalevala was 'collected' and (re-)compiled by Elias Lönnrot as a culmination of 'traditional' 'Finnish' literature in the 1830s and 1840s in Finland, a neighbor of Estonia. In Estonian case, [Ravn (2003)](_URL_6_) lists three possible historical connections of constructing their national identity, namely the ruling Russians, the Baltic Germans mainly resided in the cities, and the Finns, were provided. [Friedrich Amelung](_URL_2_), cited as a first authority in [Wikipedia](_URL_1_) that identified the connection between the guild festival in Baltic countries and Christmas tree, usually ascribed to early modern Germany, belonged to this second group, the Baltic Germans. It was also worth mentioning that he was a kind of self-taught historians (he was a plant manajor majored in Chemistry, and also seemed to be famous for his chess study). For him and his brethen Baltic Germans, it would be a delightful joy of 're-discovering' the possible cultural connection between his land brethens' 'traditions' and the famous practice of Christmas tree in his kind's homeland, Germany. "
]
}
|
[] |
[] |
[
[
"https://www.nytimes.com/2016/12/22/world/europe/who-tossed-on-the-first-tinsel-two-baltic-capitals-disagree.html",
"https://en.wikipedia.org/wiki/Christmas_tree#cite_note-29",
"https://bbld.de/0000000052290717",
"https://qmro.qmul.ac.uk/xmlui/bitstream/handle/123456789/8672/Strenga_G_PhD_final_06012014.pdf",
"https://www.npr.org/2016/12/23/506759031/who-first-decorated-the-christmas-tree-historian-says-neither-latvia-or-estonia",
"https://doi.org/10.1080/01629778.2018.1511605",
"https://doi.org/10.1111/1469-8219.00078"
]
] |
|
ebgkls
|
The explanation of the Coriolis force that everyone gives about the relative difference between linear velocities on Earth. Is that correct?
|
[_URL_0_](_URL_0_)
This is a video that gives the same explanation. Mind you, it's not the only one. Every video/article online that attempts to explain the Coriolis force uses the same logic. I have even had professional lectures on universities where they attribute the Coriolis force on the relative difference of linear velocities.
My question is simple: Is this explanation correct? From my experience and knowledge, it's not. The Coriolis force has nothing to do with initial linear velocities that are preserved due to inertia. It's a purely fictitious force that is a result of different observations from the perspective of a rotating frame of reference
In fact the explanation of the above video, can't explain why there is still Coriolis force when the object moves on the meridional direction, e.g. when it moves along a constant latitude.
I would like to know what are some of your opinions and if you agree with my statement. Thanks in advance.
|
askscience
|
https://www.reddit.com/r/askscience/comments/ebgkls/the_explanation_of_the_coriolis_force_that/
|
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"A lot of people try to give \"simplified\" or \"heuristic\" descriptions of the Coriolis force, and end up getting it wrong and/or not covering all possible cases.\n\nLike you said, it's just one of the three terms that pop up when you transform the acceleration vector into a rotating reference frame (the other two being the centrifugal and Euler terms).\n\nAll you need to understand the behavior of the Coriolis force in **all** possible cases is to consider the cross product **v** x **Ω**, where **Ω** is the angular velocity of the rotating frame and **v** is the linear velocity of the object you're interested in, in the rotating frame.\n\nThe Coriolis force is proportional to this cross product. As long as you know how to evaluate a vector cross product, you can figure out what the Coriolis force is under any circumstances.\n\nSome examples of special cases:\n\n* For an object moving in the N-S direction at the equator, the Coriolis force is zero.\n\n* For an object moving in the E-W direction at the equator, the Coriolis force is maximal, and acts in the up-down direction. (This is an example of the \"Eotvos effect\".)\n\n* For an object moving horizontally at the poles, the Coriolis force is maximal, and deflects in the perpendicular horizontal direction. (This is an example of the \"Coriolis effect\".)\n\n* For an object moving in the up-down direction at the poles, the Coriolis force is zero.",
"The explanation in the video is fine, as was the answer that got removed for some reason. However, it only deals with the Coriolis effect in the narrow sense: The Coriolis force (cf RobusEtCeleritas's answer) is more general and responsible for both the Coriolis effect tangential to earth's surface as well as the [Eötvös effect](_URL_0_) perpendicular to the surface.\n\nHowever, I would argue the most revealing approach is not to decompose the Coriolis force tangentially and perpendicularly to the surface, but parallel and perpendicular to the axis of rotation, eg by using cylindrical coordinates ρ, φ, z.\n\nIf you do that, you should (hopefully) arrive at\n\n & nbsp; & nbsp; **F** = -m **ω** × (**ω** × **r**) - 2 m **ω** × **v** \n & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; = m·(ρω² + 2ωv^(φ)) **e^(ρ)** - 2 mωv^(ρ) **e^(φ)**\n\nwhere the centrifugal force has been included as well.\n\nThe last term is what's alluded to in explanations for the layperson: If you move closer to the axis, you have an excess of azimuthal velocity compared to a corotating observer, which manifests as an acceleration. It's not hard to derive this considering radial inertial motion on a spinning disc.\n\nLooking at the contribution of the Coriolis force in the radial direction, azimuthal motion in direction of rotation strengthens the centrifugal force, whereas motion in the opposite direction will weaken the centrifugal force.This agrees with intuition, and there might be a way to derive this in a few lines as well, though my own attempt just failed.\n\nNow, on to your claim that\n\n > The Coriolis force has nothing to do with initial linear velocities that are preserved due to inertia. It's a purely fictitious force that is a result of different observations from the perspective of a rotating frame of reference\n\nFictitious forces arise precisely because velocities are preserved. Conceptionally, this is how I'd explain what happens:\n\nThe problem with Newton's laws is that **v =** *const* is a frame-dependent notion. To fix this in a differential-geometric setting, we introduce a covariant connection on the tangent bundle, allowing us to define what we mean by 'persisting in a state of motion'.\n\nThis also allows us to split the double tangent bundle - the place where accelerations live - into a 'horizontal' inertial part and a 'vertical' non-inertial part.\n\nIn terms of inertial coordinates, this is trivial and the equations of motion will read\n\n (x', v') = (v, a)\n = (v, 0) + (0, a)\n\nwhere **a = F/m** is the vertical, non-inertial component of acceleration due to 'real' forces.\n\nBut what happens if we perform a coordinate transformation **y = y(x)**?\n\nIntroducing the transformed velocity **w = Dy⋅v** this now reads\n\n (y', w') = (w, (Dy⋅v)')\n = (w, Dy⋅a + D²y⋅v⊗v)\n = (w, D²y⋅v⊗v) + (0, Dy⋅a)\n\nwith a non-trivial horizontal component corresponding to a 'fictitious' force."
]
}
|
[] |
[
"https://www.youtube.com/watch?v=HIyBpi7B-dE"
] |
[
[],
[
"https://en.wikipedia.org/wiki/E%C3%B6tv%C3%B6s_effect"
]
] |
|
1rx4a6
|
day trading on the stock exchange
|
This is something that has always interested me, but also something I never fully understood. I even attempted to read a book or two on stocks but none of them really touched on day trading.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1rx4a6/eli5_day_trading_on_the_stock_exchange/
|
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"Hey look, finally an ELI5 that I can be helpful on.\n\nDay trading is a form of trading where you basically want to start and end the day with no open position. An open position means you either own a stock/option or haven't covered a short (I'm assuming you know what these mean if you've read up on stocks). Because of this, it is inherently risky as you are essentially trying to make money on the volatility of that particular day as opposed to large price increases over time. \n\nThe gains from day trading are seemingly small but if a trader averages say .5% gains and trades 200 days out of the year then they are still earning quite a bit of money. \n\nAs far as day trading strategies go, most of them involve a combination of purchasing common stock and buying/selling options as insurance or as a means of making more money. If you're interested to know some specifics as well as the payouts from different strategies then feel free to PM me.\n\n**TL:DR** Day Trading is where you start and end the day with no open positions, all money starts and ends in a cash account. ",
"Stocks fluctuate in price. Investors will attempt to purchase a stock in hopes of it gaining price over a period of time- thus making money.\n\nDay traders hope to do the same in much smaller time frames, usually multiple times a day, and with much smaller price movements. ",
"The math on day-trading as your means of living:\n\nLet's say you sell at a profit of $200 per day. \n\n$200 less 30% tax = $140 (30% is an average).\n\n$140 less fees of, say, $20 per day = $120 net profit per day.\n\n$120 x 5 days a week = $600 per week.\n\nPer month = Ends up being about $2,400.\n\nYou're netting about $28,800 after taxes.\n\nYour gross income would be about $50,000. \n\n($200 x 5 days/week x 50 weeks or so = $50,000.)\n\n\nIt's hard to make $200 a day on the market if you only have $5,000 or $10,000 to start. It's possible, but hard.\n\nThe worst thing about day-trading is being patient. NEVER buy first thing in the morning - stocks will dip and flinch more then. Buy around 2 hours after they open. You have to have discipline. Don't buy stocks over $10. They won't jump fast enough if you're not investing all that much. (These are my personal rules, just passing them along).\n\nI like Yahoo Finance as a nice summary of what's going on. There are articles on that particular stock, so it's easy to see if it will go up or down. Watch to see if a bunch of tech companies are about to have a Summit. Watch if a bunch of energy CEOs go on an all-CEO retreat or whatever. Watch if financial institutions are about to settle a lawsuit - people will begin reinvesting and the stock will go up.\n\nRemember that a trade fee online is usually $10 each way, so that's $20 by the time you sell it. Get out if your stock keeps going down, or commit it to long-term. Discipline. \n\nLastly - google \"stocks that fluctuate a lot\". If one just went way down, find out why, because it might not necessarily be a bad thing soon. Find out if they're going to fix the problem, then keep it in the back of your mind. Then invest when news breaks that the problem will be fixed. Then buy it. Or don't if it's too risky. \n\nLook at the 5-day, 1-month, 3-month, etc. chart, use common sense - is the stock at its peak for the first time in a year? (Do not invest.) Did it just go way down last week and is now trying to recover? (Maybe invest.) Is it flatlining or going up and down and up and down? \n\nWhat is the volume size? Is it 12,000 or 12,000,000? A volume of 12,000 is slow-moving. More volume will move faster.\n\nDefinitely watch Cramer, because if you see what he's said about stocks, you'll notice that the stock will make a jump (probably a day-trader jump), because people do whatever Cramer says to do.\n\nAlso see r/personalfinance.",
"Long term investors buy into the stock market hoping for an overall long term rise in stock price.\nDay traders, otoh, play the small variations that occur during the normal trading day. Whereas investors buy with the intent of holding stock, day traders buy with the intent on flipping that stock as soon as profitable.\nA day trader may sell after a gain of only an 1/8th of a point, or they may hold longer if the stock continues to rise, but they're most likely unloading it before the end of the day.\nFWIW, I think the mass influx of day traders in the past decade has severely increased the volatility of the market, and taken the \"what have you done for me lately\" mentality to new and dizzying heights."
]
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|
[] |
[] |
[
[],
[],
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[]
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|
9b3ac7
|
why does having chalk increase your grip while on something like monkey bars?
|
& #x200B;
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9b3ac7/eli5_why_does_having_chalk_increase_your_grip/
|
{
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"Chalk is typically made of magnesium carbonate which serves the purpose of keeping your hands dry. The reason it works isn't that it directly improves grip per se, it's that it prevents grip from degrading in the face of moisture. For most uses that moisture comes from your sweat, but in rock climbing you often encounter moisture from rocks as well.\n\n",
"Rock climber here. Chalk improves friction between your hand and the object you are grabbing compared to having a sweaty palm, but is actually not as grippy as a dry hand. As a climber you have to chalk up often while climbing but often try to not overchalk your hands. Absolutely caking chalk onto your hands is no good. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
19kuwa
|
Did U.S. Marines carry out night operations during World War 2, on the scale that they do now?
|
Hey Historians, I saw in Letters from Iwo Jima, that the Marines did a bunch of a few night ops, such as defecting from their spot to go on a patrol. I was wondering if the Marines would actually do this, go on missions at night?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/19kuwa/did_us_marines_carry_out_night_operations_during/
|
{
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"c8p5dz0"
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"text": [
"The key moment of the Battle of Guadacanal was when the Kawaguchi brigade attacked a ridge to the south of Henderson field. That night, Carlson's Raider battalion and other elements of the First Marine Division held onto what soon was called Bloody Ridge, in an all night long battle. "
]
}
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[] |
[] |
[
[]
] |
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1qmsxy
|
Is there a minimum amount of molecules needed to form an ice crystal?
|
For instance: would just two water molecules be able to come together and form a tiny crystalline structure or would a larger group of molecules be needed for it to be considered an ice crystal?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1qmsxy/is_there_a_minimum_amount_of_molecules_needed_to/
|
{
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"text": [
"You'd normally use the word 'crystal' for a bulk solid, so something that's greater than a 10 nm radius or so (that's just my own feel of it though). For a just a dozen molecules or so it'd be a 'cluster'. \n\nIt's just words though, there's no specific point where a cluster of coordinated molecules becomes a crystal.",
"Any two or more water molecules that come together to form solid water (ice) will form a structure with the same geometry as a larger ice crystal.\n\nWhen you can actually start calling that structure a crystal is probably more of an opinion."
]
}
|
[] |
[] |
[
[],
[]
] |
|
e5hhyi
|
how does fat accumulate symmetricaly in both our legs when we become overweight. how do our legs and arms get the same amount of fat stored in them?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/e5hhyi/eli5_how_does_fat_accumulate_symmetricaly_in_both/
|
{
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"Fat is stored in cells called Adipocytes and generally they are evenly dispersed in our body",
"From an evolutionary viewpoint, it's beneficial to keep the body balanced. If you gain significantly more fat cells on the right side of your body than the left, your center of gravity will shift to the right. This would make even basic walking more difficult and stressful to the body, which would make surviving long-term and passing on your genes more difficult. \n\nIn essence we gain weight evenly over our center of gravity (as far as right/left) because gaining weight unevenly makes it even more difficult to survive."
]
}
|
[] |
[] |
[
[],
[]
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||
8bg5fw
|
why is the reversible, and compact design of usb-c only made recently? why couldn't they have used this design decades ago when they were designing usb-a?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8bg5fw/eli5_why_is_the_reversible_and_compact_design_of/
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"Reversible plugs require better microcontrollers to determine powe distribution.\n\nBasically directional plugs are dumb and easy, you always know what pin is going to be where and sending what. If its directional then you need a microchip to check which pin each slot got and how to act accordingly\n\nThink like water taps that have 2 handles (one hot, one cold) or just one lever. The one lever is more complicated to design and requires more balancing and math on the engineering side, the 2 tap one is cheaper and leaves it up to the user to know what each does.",
"One of the other deals with this: USB was meant to be a replacement for SERIAL interfaces (Eg, RS232). It was a way to quickly transmit data that happened to also provide a little bit of power. Today, it's primarily used as a power source that happens to have a data exchange.\n\n\nIn terms of transmitting information like RS232, USB was meant to be a semi-permanent, hot-swappable interface for things like mice, printers, keyboards, and gamepads. No one was thinking about charging phones. The USB-A and B ports were designed to be fairly strong on their own. USB C is a significantly \"weaker\" physical connection.",
"As with most improvements things take time.\nWe learn over time what works, what doesn't - and we gain additional knowledge in the process that brings to mind new ways of doing things.\n",
"USB in and of itself is an attempt to condense parallel communications into a serial interface. When USB was designed, they condensed 8 pins to 4. I am not trying to say the original RS232 port was parallel, it was serial; but the logic to achieve the same ability with fewer pins was one of the main priorities when USB was designed.\n\nFewer pins + more data throughput = much beefier controller chip needed.\n\n\nIt should be noted that only in the last few years has technology become cheap enough to push the limits of the USB standard. Which also means that the designers for USB had already attempted to use the most powerful controllers they could.\n\nThis entire conversation is more or less a display of how technology 'know-how' doesn't always keep pace with the literal technology available. The technology exists to push the standard much farther, but the price per controller is holding it back. Remember, BILLIONS of devices use this standard.",
"What is obvious in retrospect was not necessarily obvious at the time. Engineering always involves compromises, and reversibility would have been low on the list. At the time USB was relatively compact, robust, and convenient, but was pushing the mass manufacturing of the time. Then you saw the mini USB, and later micro USB. Reversibility wasn’t seen as a necessary feature until Apple created the lightning port. It was only then that the market began demanding reversibility in the plugs.\n\nSo really it is a combination of vision based on where they were coming from, engineering compromises, manufacturing capabilities, and market forces.",
"They simply didn't think about it at the time; no technical reason why they couldn't have implemented reversible plugs decades ago.\n\n*edit* also _URL_0_",
"If you look at Apple they were always trying to get here. They were the first to release a computer with no dedicated keyboard or mouse ports, USB all the way.\n\nThey were pushing firewire which was better than USB for a decade, they used DisplayPort and miniDP before almost anyone, and released lightning in 2012, giving a small reversible connector.\n\nSince USB is a standard that has a consortium behind it, it moves at a snail's pace in regards to upgrades.",
"Why is the 4K led tv only made recently? Why couldn't they have used this design decades ago when they were designing the crt?\n\nJust kidding. The short answer is that sometimes obvious designs are only obvious once they are designed.",
"In mass electronics the answer is almost always cost. Today on Mouser a USB-C socket is over 3x more expensive than a USB-A. Multiply this out across a few million units and you are talking real money. The USB forum, which represents device manufacturers, wanted to minimise these costs.\n\nThere were also design compromises which were made which were later shown to be less important than first thought. Notably the wear and directionality of the USB cables.\n\nThe USB forum decided on a deliberate policy of wearing the plug, not the device. So a USB micro B plug has small spring elements on the bottom that lock it into the socket. Being a mechanical bendy device these wear with time, a deliberate choice was made to take this wear on the plug. Time and the lightening connector have shown that the wear is less of an issue and consumers don't care. With USB-C the bendy fatiguing spring is in the socket of the device allowing for a cleaner appearing plug.\n\nInitially USB was designed with a strong Master-Slave relationship. One issue they wanted to avoid was pairing a Master-Master or Slave-Slave, a common issue with Serial and led to atrocities like null modem adapters. Part of avoiding this was to have a distinct Master and Slave plugs so building the wrong relationship was physically impossible and obviously not going to work. Mobile phones buggered this all up with USB On-The-Go, which allows a device to be a Master one minute and a Slave the next. With this compromise made the initial rational fell through and now we have identical USB-C plugs on both ends of a cable.",
"The needs have changed as time went along.\nThey had different things which had different uses. Now USB C can transfer energy and also specific information. I have USB c for my laptop and phone. They didn't have cables for phones before, and didn't even consider charging it for a laptop. ",
"Because we humans can be slow to build the obvious. For example mankind has had the wheel for thousands of years. Mankind has had luggage of various types, also for thousands of years. Wasn't until about 1970 that someone thought to put wheels ON the luggage.",
"Some more food for thought: USB connectors were designed in the '90s. At the time, there weren't really any devices small enough to *require* super compact connectors. They did provision Mini USB at the time, and it took a while before devices got small enough to necessitate the introduction of Micro USB. Additionally, larger connectors are more physically robust, so this would have factored into the decision.\n\nRegarding reversibility: either you make the connector keyed, so it can only be inserted one way, or you make it reversible/symmetrical. If there's no perceived advantage to one solution or the other, then both seem equally viable. It's possible that a keyed design was chosen at the time to minimize the complexity of the connector in manufacturing. Also keep in mind that at the time of USB-A's design, virtually every data connector standard used a keyed design. Reversible connectors were pretty distant on the industry's radar - consider again that connectors hadn't gotten super small yet, and reversible connectors are most useful at small sizes where it becomes a pain to fit the keyed ones.\n\nSome better-informed responses already in the thread, but I wanted to add these points for consideration! The TL;DR of the whole thing would be that it wasn't a matter of technical limitations, but simply that there was no perceived need or benefit at the time to make tiny reversible connectors. Those just plain weren't necessary for the intended purpose of USB-A in the timeframe during which it was designed.",
"I think the real question is why USB mini-b and especially (!) micro-B didn't have reversability as a feature",
"There is no technical limitations. No one thought of it till Apple did the Lightning cable. Then that influenced USB C cable to be reversible.",
"USB was abismally easier to connect than previous serial or parallel interfaces, which were 4-5 times usb size, had dozens of pins and had to be actually screwed. Complaining about why wasn't it reversible from the beginning is like giving a nice car to someone traveling by mule and him refusing because seats are not leather.\n\nEdit: Yup, I'm abismally wrong and I should've used a different word. Sorry, English is not my first language. ",
"Smaller connectors require better manufactoring technologies. And reversible data connectors require additional software and/or hardware to work. And when you look at the problems with power delivery it still seems to be quite difficult to do that stuff properly in 2018. In the 90s this would have just meant huge costs for no real benefit.",
"USB-A was introduced in 1996. At that time, almost nobody had PCs, laptops rarely existed, and Windows 95 was a revolutionary operating system. Google was launched in 1997. The \"revolutionary\" Nokia 8110 featured in The Matrix had not been launched yet.\n\n_URL_0_",
"There are a lot of really good answers in here, but I think there's an angle that isn't getting much attention.\n\nThe direct answer to your question is that there was no technical barrier to engineering and mass-producing a reversible connector that would have had the same technical capabilities of a USB 1.0 connection. It would have been simple to create a connector that was mirrored on each side and thus could be inserted with either side facing up.\n\nThe problem is that engineers don't always consider the user experience. And to be fair, that's not their job. Their job is to make things work well. Sure enough, USB-A connectors work well *as long as you follow the instructions and insert them properly*. But as anyone who has used a USB-A connector knows, the experience is often mildly frustrating: you try to plug it in, but it won't fit, so you flip it over, and it still won't fit, so you flip it over again, and surprise, it fits.\n\nThe companies that got together and came up with USB -- including Microsoft, Intel, IBM, and several others -- should have done some user acceptance testing. That is, they should have asked a group of everyday, random, run-of-the-mill people to come in and try using the thing with no instruction other than \"plug this in\".\n\nThe reason they didn't do this is, ironically, a huge part of why USB was invented in the first place. When USB was being developed in the early 1990s, most people had only a basic working knowledge of how to use a computer. They could turn it on and launch WordPerfect, but couldn't hook up a new printer. USB was meant to help by greatly simplifying (and standardizing) the connector, and greatly simplifying how drivers were installed (prior to USB, installing a peripheral typically involved a nightmare of IRQ, DMA, and address settings, as well as installing software that was not at all user friendly).\n\nSince this was all beyond the grasp of the average computer user who wanted stuff to \"just work\", the coalition beyond USB didn't really consider their experience. Since USB was such a massive improvement over the current standards, it was assumed that everyone would love it. And we did, mostly.\n\nTL/DR: There were no physical, technical, or manufacturing limitations that prevented this. It was just never anticipated that it would be an issue.",
"The design is not good for immediate identification. Generally ports are made so that they are not reversible. That was one of the considerations when making them originally. A unique shape, that only fits one way.\n\nUSB c is not very unique and is not a very good design when speaking in terms of safety and longevity.\n\n_URL_0_",
"I haven't seen it mentioned here, but one of the bigger \"Electrical\" (read not electromechanical) complications of implementing USB-C is the forced inclusion of a signal mux for the data lines. This wasn't always easy (and certainly at high speeds, can be quite hard). A good bit of technology had to catch up to do this affordably.\n\nE.g. in simple terms if you happen to have wire A mated to wire A, B to B, C to C by flipping the connector you mismatch the letter pairings in the cable. \n\nFrom a hardware point of view, there's an integrated circuit that than \"fixes\" the marriages of the different lettered wires regardless of the orientation of the physical connector.\n\nThere's more to it of course, there's a good bit of science involved to negotiate the different power deliver requirements (and increase the voltage) to mitigate problems with increasingly small wire gauge. But I won't dive too deeply there. \n\nSource: have designed / laid out USB 3 connectors\n\nAnd the less ELI5 version:\n_URL_0_",
"All these answers are great but realistically what happened is this:\n\n- no one thought you could make a reversible cable\n- no one asked for a reversible cable\n- there was so much stuff to do on this project, even if someone did think of a reversible cable it was thrown down to the lowest priority\n- Apple came out with one and suddenly the masses were like “oooooh I want that”\n\nThis goes with the theme of Henry Ford’s “if you asked people what they wanted they’d say a faster horse”",
"Everyday usability just recently found its way into product design as a valuable thing to do",
"Imagine a power plug with two \"pluggy-inny\" ends.\n\n(Old USB plugs are just conductors from the pin on the computer to the pin on the device. USB-C has circuitry to figure out which end is plugged into what, and which direction the zappy stuff goes. Even the first USB-C cables were a mixed bag, and a lot of times a high-draw device would melt a low-capacity cable.)",
"Electrical engineer here, you're basically asking engineers why we don't predict the future... where our society will be and what its ready to adopt 10 years ahead of its time is hard to do. Basically we have like 10 viable paths for technology to go and no idea what will win out so all we can do is set it up to be compatible with the future as much as possible without knowing where we will be. At least USB A B and C are similar enough you dont need huge hardware and software overhauls to use or be compatible...\n\nAsk the question: why didnt we design the USB C to incorporate USB D, E, or F designs. Well because we dont have a clear idea of what technologies or standards will be incorporated.\n\nStandards are developed a few years after technology is found or become mainstream. The USB D tech is just becoming viable and understood now and im sure theyre starting to talk about and draft it, but you you need to wait until its mostly agreed upon by the industry to start to use it in your designs\n\nAlso, technically its not like we couldnt have designed it to be reversible 10 years ago, wires and PCBs have not changed much relative to a simple USB plug. its most likely just that there were bigger problems the engineers working on at the time they had to worry about rather than user friendliness. User friendliness comes last when it comes to sorting out technology breaking bug fixes and hardware issues. USB Has now gotten to the point that the engineers working on it have time to go and design it to be ergonomically friendly and reversible, its just taken time to come around to it. \n\nLastly maybe the idea just didnt exist, or if it did it wasnt mainstream enough for everyone to want to implement it. Unfortunately not every technology has a steve jobs type who completely innovates, changes it over night, and includes user friendliness. These are being designed by engineers so new technology usually takes some time before it becomes user friendly enough someone other than an engineer is willing to add design to it, or for an engineer to even just think of that new innovative design.",
"Thats like saying why didn't we have SUVs until they were invented, we already had cars and trucks. The USB drive was a breakthrough itself when first invented and it could only handle about 12Mb/sec, but as they were used the limitations and issues were discovered and addressed in future models. In fact, although it is called a USB-c, it is not the same as USB3.0, which is a standard for speed and other features, whereas USB-c is referring to the connector shape so cables from different companies can have much different speeds.\n\n_URL_0_\n\nRegarding why it didn't switch designs earlier, the usb connector was one of the smallest ports on a regular computer until recently. Even laptops would have a vga out and various other ports which kept the design of the cases deep enough to accommodate multiple usbs stacked on top of eachother. Add in the fact that a USB3.0 port is backwards compatible so a first generation USB device will work without needing any adapters. This leads to most peripheral manufactures to use the USB standard, and if most peripherals use that standard then pc manufacturers have little incentive to switch to a whole new port that few people need or want.\n\nNow, with the desire to make smaller and smaller devices, even 1 USB port can be too large to fit in the laptop case, but the real benefit for computers is the added speed. But the real driver pushing adaption of the USB-c are cell phones, where even the headphone jack is too large for some high end devices as they try to get thinner and thinner. And Apple computers, but they just really want to sell you all the adapters you need to connect to the devices they sold you with your last computer.",
"Why didnt we use new technologies before they existed??? WHY?v?",
"I'm not completely familiar with how USB-C works, but if it's anything like Lightning it works by probing the cable to figure out which way it is oriented and then choosing which pins to use, which requires extra computing power and circuitry. That's nothing today, when even an IO chip has considerable computing power and high-density circuit boards with nearly microscopic components are universal, but back in the mid-1990s it would have been seen as a pointless waste of resources. At that time I don't think there were *any* multi-pin computer interfaces that could be plugged in more than one orientation. It simply wasn't something that anyone had thought of or needed. USB *was* unique in that it was the only (non-round) computer connector whose orientation was determined only by the internal pin layout, not by the external shape of the connector, but it is still pretty easy to tell the correct orientation just by looking at the port.\n\nAlso, in the 1990s the concept of \"hot-swapping\" was still brand new and rarely implemented, for the most part plugging and unplugging devices had to happen when the computer was turned off. While a big complaint about USB today is that you can't see which way the port is oriented when you're reaching behind your monitor that simply wasn't an issue back then. Even though USB *could* be hot-swapped there were no USB data storage devices yet (apart from semi-permanent things like Zip drives and CD burners), so most things would be set up once when you could see the ports and then left plugged in forever. And for the rare times you *would* need to hot-swap a USB cable the one or two ports on the front of a computer were enough. It wasn't until years later, with the proliferation of USB storage devices, digital cameras, media devices, and especially USB 2.0 that the need to constantly access and use the USB ports became a big deal.\n\nAnd, finally, USB-C for the most part solves a problem that doesn't really exist. While it is definitely more convenient to not have to worry about orientation it's not like that is a \"must-have\" feature, and while it is definitely smaller which is a bonus for smartphones it's not any smaller than existing smartphone ports were and the need for small connectors is a very recent trend. Back in the mid-1990s when USB was being developed even a full-size USB port was far smaller than any of the legacy ports it was replacing, and even mobile devices were large enough to fit a full-size port so there was no need to make it smaller.",
"Because morons on reddit made it a meme that they are stupid and cant plug a cable it. It only goes one way in and has a mark on one side, do you need more than that to indicate if it is the right way or not?",
"The pins have to be made much more scaled down to fit them all in a compact conductor. This means higher cost. In the old days of USB 1 and 2, you only had like 6 pins. Now with USB-C you have something like 18. (You have 8 for superspeed pairs, 4 for normal high speed data, 4 vbus, 4 gnd, 2 sidebands, and 2 CC pins) Almost 1/4 of those are only used because the USB-c is flippable so it isn't the most effective use of real-estate from a connector point of view.\n\nYou also have a lot of neat features for USB-C that frankly weren't thought of way back then. Those sidebands can be used for \"alt-modes\" for displayport, for example. There's also support for Power Delivery too. These needs didn't exist until recently.\n\nTl;dr: \n\n1) Manufacturing small enough pins to fit 24 pins in such a small connector\n\n2) USB A/B type connectors were good enough for what they were needed for at the time. With more interest in alt-modes and power delivery.\n\n3) Cost",
"USB includes the idea that one device is not only in charge of the communication, but may have to supply power to the other. A reversible connection could lead to two devices plugged together that are both supplying 5volt power (which could damage one or both). The standard is now widespread so the electronics for a USB transceiver that can handle the power negotiation are cheap and easy to get. But when it first came out, it was a lot simpler to design equipment knowing that you could not plug two master devices into each other.",
"Its not so much a technical limitation....\n\nWhen you invent something, the moment it is invented is it the best version of it that it could be? Probably not.\n\nWhy do apple and microsoft keep realeasing all these terrible in-betweener operating systems when they could just release the best one!?",
"Having a symmetrical connector only makes sense if you anticipate that people will be plugging/unplugging things frequently. It also costs more to manufacture. Smaller connectors cost more to make too, because the tolerances need to be tighter.\n\nWhen USB was designed, they did anticipate \"hotplugging\" (adding and removing devices while the host computer was on), but not to the extent it actually ended up happening. So it made sense to have a cheaper, easier-to-manufacture connection that had an orientation, just like every other device.\n\nThey didn't anticipate people walking around with USB cords in their pockets, or pocket computers that were so thin, so there was no particular reason to put engineering effort into compact size (though microUSB was added in 2007 in part because people were making small enough devices that a smaller connector made sense)."
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[],
[
"https://images-na.ssl-images-amazon.com/images/I/41htM9RiX%2BL._SY450_.jpg"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Nokia_8110"
],
[],
[
"http://www.belkin.com/us/Resource-Center/USB-C/USB-C-counterfeits/"
],
[
"https://www.reclaimerlabs.com/blog/2017/1/12/usb-c-for-engineers-part-2"
],
[],
[],
[],
[],
[
"http://www.qacqoc.com/usb-type-c-vs-usb-3-0-whats-difference/"
],
[],
[],
[],
[],
[],
[],
[]
] |
||
f5uyyv
|
why can flood waters get 20-30 feet high on flat land, when water will fill it's given space, wouldn't the water "just flow away?"
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/f5uyyv/eli5_why_can_flood_waters_get_2030_feet_high_on/
|
{
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"fi0vrdd",
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],
"score": [
11,
3,
2
],
"text": [
"It is flowing away..\n\nThrough your house and your neighbours'\n\nWater takes volume, if a lot of water arrive in a riverbed, it will overflow and take another path.",
"There is no flat land, to start with.\n\nWhen rain falls, it flows from higher spots to lower spots. When there is a constraint, like a valley with a river running through it, the level of the river has to rise to accommodate the extra water. All the water is moving, but its speed is controlled by the steepness of the bottom of the river. It will \"flow away\" eventually, but for the interim period when more water is flowing in from the wide rainshed than can flow out through the narrow river, the build up is called a flood. Human efforts to keep flooded areas small leads to much higher flood waters than would occur is we let the water spread out and flood more homes.",
"Water in the ocean gets pushed around by wind and tidal forces. A lot of wind and high tide can push water from the ocean onto land.\n\nWater in a river flows down with gravity. More rain- or snowfall at the river's origins (e.g. a mountain) means more water in the river, which can cause the it to overflow beyond its normal boundaries. In that case, it's gravity that pushes water onto land. \n\nSo, forces like wind, tides and gravity can push water away from one place and towards another place. Eventually, if that second place isn't a lowly situated basin, the water may flow away again to a lower place (usually the nearby river or ocean that it came from). Or, it may evaporate. But that doesn't stop water being on (usually dry) flat land some of the time, and even reaching great heights. All you need is the right forces to push it there."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
5w9tay
|
why are old tv screens round on the edge.
|
Why is the corner of my crt tv round so that it cuts off the corners of the screen?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5w9tay/eli5_why_are_old_tv_screens_round_on_the_edge/
|
{
"a_id": [
"de8hyee"
],
"score": [
4
],
"text": [
"In addition to problems of fabricating the glass (remember, there’s a vacuum inside, so it has to hold up against roughly seven pounds per square inch of pressure from the atmosphere), it’s harder to get the electron beam to behave in the corners. For years, color TVs, which had three beams to control, were outright round all up and down the sides.\n\nNow, of course, they could simply have put a perfect 4x3 image into the center of the screen, but test after test demonstrated that consumers would rather have a big picture with the corners cut off than a perfect picture that was smaller.\n"
]
}
|
[] |
[] |
[
[]
] |
|
2vi5fp
|
pharmacies - what in the world is taking so long?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2vi5fp/eli5_pharmacies_what_in_the_world_is_taking_so/
|
{
"a_id": [
"cohuses"
],
"score": [
13
],
"text": [
"I don't think you realize the volume of prescriptions they are dealing with. They pretty much fill them in order that they are received.\n\nWhen they then get to your prescription, they just don't fill it and hand it to you -- *or just grab it off the shelf in the case of your steroid cream* -- they review your computer file to make sure that you aren't allergic to that med, that you aren't also taking other meds that would cause an unintended reaction, they confirm that the health care provider that wrote the prescription is legally allowed to do so. Then there's the relatively routine printing of the instruction and warning labels. The pharmacy techs handle a lot of the routine steps, but these are all verified and double-checked by the registered pharmacist on duty. These steps and double-checks all take time.\n\nThen there's the explanation of the med to you... how/when to take it, any warnings, or things to look out for, or whatever. They do this for each and every medicine and each and every patient filling a 'scrip.\n\nIf you are a relatively healthy person, there might not be a lot to check for you. But imagine some of the folks with more medical issues than you that are \"ahead of you in line\". This process can take quite a while to go through especially for someone with multiple medical problems filling several scrips at once. It's really easy and common for the pharmacy to get backed up.\n\nSorry.... you just have to wait. If it's really important to get in/out quickly, treat the pharmacy like the DMV and be the first one there. Or, just drop the med off and come back several hours later or the next day... or have your doctor call in the 'scrip.\n\n**TL;DR**.... stuff takes a long time to do, yo.\n\nEDIT... I forgot about the insurance companies that they have to deal with. Private pharmacies deal with a number of insurance companies. Each insurance provider has their own protocols that have to be verified and followed as well before handing you your medicine. This also slows the system down. Even if you are straight up paying for your med, imagine all of the people in front of you who aren't. Remember, unless you are having an actual emergency -- *like an asthma attack and need an inhaler immediately* -- it is first come, first served, and you have to wait in line."
]
}
|
[] |
[] |
[
[]
] |
||
ddzqrt
|
how to tell the difference between polar, non polar, and covalent bonds
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/ddzqrt/eli5_how_to_tell_the_difference_between_polar_non/
|
{
"a_id": [
"f2pl2ss",
"f2pp2vz"
],
"score": [
11,
3
],
"text": [
"polar and non polar bonds are covalent bonds. Bonds/molecules are polar when the electrons forming the bond are unequally distributed, like water molecule has bit of a V shape, but non-polar carbon dioxide is in line, O-C-O. \nIn ionic bonds the electrons are entirely on the other atom.",
"Polar and non-polar aren't types of bonds. Instead they describe whether the electrons in a molecule are equally distributed across the entire molecule. All polar/nonpolar molecules contain atoms that are covalently bonded together, that's when atoms have to share electrons with each other so that they're stable.\n\nPolar and nonpolar arises from the fact that atoms don't share these electrons equally. Polar molecules, for example water, have unequal electron distribution, which causes one side of the molecule to be positively charged and one side to be negatively charged, thus they have poles, kinda like a magnet does. Nonpolar molecules don't have this unequal electron distribution."
]
}
|
[] |
[] |
[
[],
[]
] |
||
2dl4y1
|
Were ancient battles actually as large as they are modernly depicted?
|
After playing the total war game series I've been wondering if ancient wars in Rome/Japan and other parts of the world were really as large scale and chaotic as we are shown in video games and movies. Were they really as brutal and chaotic? Were the there really several thousands of people chopping each other to bits whilst having arrows and javelins rained upon them? Or were the battles more condensed and less frequent than we are told? I can't imagine when Rome was invading all around the globe that these tribes had several thousands of soldiers to match
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2dl4y1/were_ancient_battles_actually_as_large_as_they/
|
{
"a_id": [
"cjqrhhg",
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],
"score": [
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],
"text": [
"Well, most of warfare isn't big, pitched battles. The kind of battles that Total War depicts are all-the-marbles affairs, which even if they won't end the war will have a very large impact on it. Most warfare was sieges and smaller actions between parties off of the main armies, such as attacks on foraging parties.\n\nThat's not to say that these big battles with tens of thousands of soldiers on each side didn't occur. For one, Rome only fought tribes towards the north and the west. To the east, Rome fought kingdoms. Even the tribes could put together large armies under charismatic leaders to fight the Romans.\n\nThe battles wouldn't have been so... Bloody as Total War depicts them. They would usually drag on for hours, with the lines making contact, inflicting a few wounds and kills, then breaking off, over and over again. The real killing started when one side's order began to falter and a rout started. Then, there was no real protection and the losing commander would usually find himself without an army. Reserve forces could be used to cover the retreat, but even then it was hard to break contact with an enemy army.\n\nSo yeah, I'd go with battles certainly being less frequent than Total War would lead you to believe, but the big ones certainly did occur with enough frequency to decide a **lot** of wars.",
"This is an interesting question in the context of early Ireland, because we don't really know how battles worked. Our historical sources tell us *when* battles were fought, *where* they took place and *who* fought them, but rarely give us accounts of what these fights actually looked like, in terms of scale and mechanics (there are a couple of exceptions in the *Fragmentary Annals of Ireland*, but these are Irish descriptions of Scandinavian battle-customs). \n\nWe can glean a few facts, like that the Irish mostly fought with a spear and small shield, their nobles with swords and perhaps leather armour. Curiously, chain mail was known to them and is listed in the *Lebor na Cert* as a tribute to be given to kings, but it appears that they preferred to fight unencumbered by armour. Anglo-Norman descriptions of the Irish going into battle 'naked' shouldn't be taken at face-value, and most likely represents their authors' dismay at the Irish practice of fighting with little-to-no protection. Warfare could encompass conflicts as small as inter-communal raids with forces of a handful of men to major dynastic power-struggles between regional hegemons and hundreds, or possibly thousands, of warriors. It also appears that the Irish practiced a form of Christianized military-magic, and believed that invoking regional saints as though they were pagan deities could bring them victory against all odds, especially if their saint was regarded as more powerful.\n\nOne account in the *Fragmentary Annals* about the Battle of Almu between the Laigin and Uí Néill does provide actual numbers, which is the reason why I started writing this post; the description includes seemingly impossible troop numbers. The entire entry is rather terse, to the extent that the writer infuriatingly states that:\n\n > The combats of the Laigin and Leth Cuinn warriors would be excessive to relate\n\n...not that helpful, right? The gist of the entry is that 9000 Laigin warriors defeated a host of 21,000 of the Uí Néill, and then lists a few dozen kings (in the context of early Irish history, a king could be anyone from a community chief to a provincial overlord) who died in battle. This entry interests me for two reasons: the first one is the same question that you are concerned with, and second is its unusually large list of 'royal' casualties. \n\nFirst off, these sources usually have a propagandistic flair, as they were compiled by clergy to enhance the prestige of their relatives who commanded armies and fought for political dominance. These authors might have inflated the number of combatants to make the victories of their ancestors seem even more impressive, which would confer even more prestige on their dynasty. Annal authors would also legitimize their contemporary political arrangements by projecting contemporary notions of kingship and governance into the past. It is possible that if the *Fragmentary Annals* were composed at a much later date, its author might have also projected contemporary standards of warfare into the past; the Battle of Almu is said to have taken place in 722 AD, and I think that it's unlikely that kings from such an early date would be able to muster such huge hosts. What's more likely, I think, is that the author inflated the number of warriors on both sides of the battle for two reasons: they might have done so for propaganda reasons and because they were projecting their contemporary perception of warfare, where armies in the thousands might have been the norm, into Ireland's military history.\n\nThis second factor is not just me guessing as to why troop numbers might have been inflated; Irish military historian Marie Therese Flanagan has theorized that Irish literature focusing on military conflicts such as the *Cogad Gáedel re Gallaib* is more reflective of methods of warfare employed when the books were actually composed than that in the periods they are written about. It isn't too much of a stretch to then conclude that an Irish author, writing the the High to Late-Medieval period, might project contemporary army sizes into the distant past, because that's what they would have been familiar with."
]
}
|
[] |
[] |
[
[],
[]
] |
|
5uzv07
|
the reasons why the colonies sought independence from england.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5uzv07/eli5_the_reasons_why_the_colonies_sought/
|
{
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"ddy4a5t",
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2,
16,
3
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"text": [
"No representation of the colonies within Parliament, particularly given that there were numerous taxes levied on the colones by that same body.",
"The American colonies fought for several reasons.\n\n1. They didn't want to pay taxes on goods such as paper and tea. Those taxes were meant to pay off the 7 years war, but the colonists figured that they didn't ask for the war.\n\n2. King George refused to listen to the colonists' problems. They tried to raise issues, but that wouldn't have been an issue if it wasn't for the main reason, number 3.\n\n3. The colonies lacked representatives in parliament. This was the main cause of the revolution. The colonies fought against England because they had no say in their government, which ties in to reason 4.\n\n4. Enlightenment ideas about government were popular in the colonies. The founding fathers fought for the principle of a government where the people held power, not a monarch.\n\nThere's a lot more to it than that, but hopefully that summed some of it up.",
"The Colonies had a really great deal from 1607 to 1763 or so. They got to behave as independent countries essentially. They got protection from the British Military, and didn't have to pay taxes to the crown. The British Government tried to establish some taxation to pay for the French and Indian War, but they had let their \"kids\" run wild for too long, and a rebellion was on their hands."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
6zz7z5
|
how does the milk, dye and soap experiment work?
|
This experiment has you put a drop of soap into a dish filled with milk and dye. When the soap is added, you can see the dye begin to move around in the milk. What exactly is the chemistry behind this phenomenon? (I know it has something to do with soap being both a polar and no polar molecule)
Here is a [video](_URL_0_)
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6zz7z5/eli5_how_does_the_milk_dye_and_soap_experiment/
|
{
"a_id": [
"dmzbg6y"
],
"score": [
3
],
"text": [
"Milk is an emulsion of fatty globules suspended in water. We can ignore the fat for now, just note that it helps keep the dye from mixing in too fast. What we're really interested in is the water.\n\nWater is rather interesting for a molecule. It has a negatively charged end (the oxygen) and a positively charged end (the hydrogen), effectively making each water molecule act something like a bar magnet. When you put a bunch of water molecules together, they bunch up really tightly, giving water a lot of interesting characteristics.\n\nThe key characteristic is a high surface tension. The surface of the water clings to itself very tightly, forming a sticky film. We're too big to feel it ourselves, but this is why [water strider bugs](_URL_0_) don't sink into the water.\n\nSoap is also interesting. It is usually a set of molecules with a hydrophilic (water-loving) head and a hydrophobic (water-fearing) tail. That's what gives it its cleaning power (dirt sticks to one end, water to the other, and everything gets washed away). Here, however, the soap gets in the way of the self-attraction of the water.\n\nWith the surface tension broken, the rest of the water without soap contracts, bringing anything it's carrying (like dye) along with it.\n\ntl;dr: soap pops the film on the surface, the remains of which yank the dye to the side."
]
}
|
[] |
[
"https://www.youtube.com/watch?v=rqQSlEViNpk&t=37s"
] |
[
[
"http://1.bp.blogspot.com/-u_MNC8dcdyY/UQMolc0ZOgI/AAAAAAAADrU/_z9FE58kI1M/s1600/water-strider.jpg"
]
] |
|
73j0vl
|
In light of water shortages around the world, could we simply dehumidify and purify water to make it drinkable? Or gather water droplets from heat and desert areas?
|
The core of my question being "what is the easiest way of producing water depending on where you live?" Obviously this heavily varies around the world but in areas where heat gathers could we simply not 'harvest' the water?
Secondly, what could be the effect worldwide if we began to dehumidify large areas like forests or deserts?
|
askscience
|
https://www.reddit.com/r/askscience/comments/73j0vl/in_light_of_water_shortages_around_the_world/
|
{
"a_id": [
"dns6em8"
],
"score": [
2
],
"text": [
"Yes, but it requires a lot of energy to cool to below the dewpoint, and the environment you’re in is going to need to have a fair amount of humidity. There just isn’t any humidity in the desert. \n\nplaces that have humidity, and the temperature is fairly close to the dewpoint so that you don’t need to use a lot of energy, also experience rain… It’s easier just to collect rain.\n\nEEVblog and Thunderf00t have covered this in detail _URL_0_\n\n_URL_1_"
]
}
|
[] |
[] |
[
[
"https://www.eevblog.com/2017/02/22/eevblab-30-popular-science-fail-waterseer-debunk/",
"https://youtu.be/LVsqIjAeeXw"
]
] |
|
1u81ah
|
multiverse theory: is it thought that anything you can think of has happened in these universes (infinite possibility), or just everything possible within the laws of logic?
|
For example, does the theory make a universe with different physical laws possible or do these universes have the same basic physical structure, making only things that are actually possible within those laws potential universes? Say that, hypothetically, something like faster than light travel is literally impossible to achieve, does this, according to the theory, still mean it has happened in another universe?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1u81ah/eli5_multiverse_theory_is_it_thought_that/
|
{
"a_id": [
"cefens9",
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],
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2
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"text": [
"Given a potentially infinite number of universes, over a potentially infinite timespan, then it can be assumed that anything which is physically possible will occur at some point somewhere.\n\nTo answer the point about the laws of physics and how they may apply in another universe.... no one knows. We know that there are fundamental rules which apply in our universe - the speed of light like you mentioned is a good example, but in another universe the rulebook may be TOTALLY different. We simply dont know.\n\n",
"Holographic Universe by Michael Talbot is a great book that can give you a lot of information on the subject. The way i understand it is that time does not exist, there is only now. This now is contains everything in existence, i like to call it All that is. From this All that is you perceive the reality or universe that you are in tune with. Much like a radio that can pick one channel when all the radio channels exists at once. The linear experience of all that is, is what we refer to as time. Sorry not the best answer but my two cents, i will try to give more sources and experiments that lead to this theory when i get home and do some digging. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
1s33a9
|
why is second hand smoke about four times more toxic than mainstream smoke?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1s33a9/why_is_second_hand_smoke_about_four_times_more/
|
{
"a_id": [
"cdtfgq3"
],
"score": [
5
],
"text": [
"When people make these claims they usually mean over time rather then immediate. If you smoke in a confined space such as your house and then leave your kid in there for years they may get the exponential smoke inhalation. For the most part phrases like this are not based on realistic situations and are scare tactics. \n\nThat being said exposing your child to second hand smoke even if it only equal to your exposure should be child endangerment and should be punishable in court. It is morally evil and is no better then any other form of abuse. "
]
}
|
[] |
[] |
[
[]
] |
||
9ulhpu
|
how does a digital camera know when something is close or far away?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9ulhpu/eli5_how_does_a_digital_camera_know_when/
|
{
"a_id": [
"e957p1s",
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"text": [
"The passive form of autofocus analyses the image until the edges are sharp. If the focus area is wrong, the picture will be blurry where you want it to be crisp. The lens itself moves around to find the right focus. \n\nActive autofocus uses a different type of light (or even ultrasound) to focus. If there are two lights, the object's position can be triangulated. The autofocus then sends the information to the lens to focus the image. ",
"The simplest way is to use contrast auto-focus. The camera moves the focus around until it finds the point where the image is sharpest. This is a relatively slow technique because there's no way to tell which way to change the focus to fix a blurry image; you just have to try one way and, if that makes it worse, go back the other way.\n\nA better technique is to have sensors that look at the image through different parts of the lens, i.e., left and right or top and bottom. The camera can then triangulate to work out whether it needs to focus in or out. These sensors used to be separate from the camera's main sensor; they'd only work in a DSLR when the mirror was down, so autofocus wasn't possible when taking movies with the mirror locked up. In the last few years manufacturers have been using split pixels on the main sensor to overcome this limitation. This is the technology enabling the new EVIL (Electronic Viewfinder Interchangeable Lens\") cameras that are challenging DSLRs.\n\nSome old cameras did try to use active ultrasonic range finding, like sonar, for focus control. These systems were prone to focusing on the wrong subject. Modern autofocus can be smart and selective about what to focus on, or at least allow the photographer a range of choices. It can do things like recognise objects in the field of view (e.g., faces) and automatically focus on those."
]
}
|
[] |
[] |
[
[],
[]
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|
32djzy
|
why are peanuts banned from schools but not workplaces? does the danger of an allergic reaction decrease with age?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/32djzy/eli5_why_are_peanuts_banned_from_schools_but_not/
|
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"text": [
"One would hope that, by the time a person with a dangerous allergy has left school, they would be able to deal with their allergy. This probably means carrying an epi-pen and knowing how to use it, and so on.",
"Schools are responsible for the safety of their students. Businesses assume you are capable of managing your own allergy in the real world. ",
"No, by the responsibility of those who are allergic increases.",
"Because workplaces are filled with adults and schools are filled with children. Children, especially young ones, may not always know the best way to handle their own allergies and will have far worse impulse control (as that part of the brain is still developing). There is just a bigger risk of kids forgetting to wash their hands or accepting a treat they really shouldn't have or trading their lunches despite having been told not to. And because schools assume responsibility to kids while they are under their roof, someone could even sue them saying that the teachers should've prevented it from happening. (Of course sueing doesn't automatically mean they will win, but schools like to avoid lawsuits. It's bad press and a lot of money and time even if they win) When you work as an adult, your boss doesn't have that same level of responsibility over you and therefore would not be at risk of getting sued unless they were going around rubbing peanutbutter in everybody's faces. ",
"My kids school doesn't ban peanut butter. In fact we offer it as a choice with our morning breakfast program that I help run. \n\nWe obviously have a list of kids that can't have it and the older ones know better. \n\nThe classes have individual rules, there's a girl in my son's class that is extremely allergic so we can't send snacks with peanuts. However other classes with no allergies allow peanut butter and peanut included snacks. \n\nI love that our principal had adopted this way if thinking because it shows kids at a young age how to avoid it without completely banning it for everyone. \n\nSo in short: No. Not all allergies decrease with age. I have adult friends who can die within minutes of exposure. We just learn to watch for allergens and treat them as necessary. ",
"In part, because the ban for schools is a little bit ridiculous. When I grew up, kids all over took pb & j to school and the world did not come to an end. It's both over-diagnosed and improperly-diagnosed (parents who think they are allergists). It is genuinely serious for those who have it but here are the [stats](_URL_0_). ",
"They are banned in some schools, not all schools. And it is due to a heightened state of paranoia of some parents forcing school boards to set those policies. ",
"Adults who have an allergy, know they have an allergy. The danger at schools is that there might be a child who develops and allergy and doesn't know it, or is a kid and didn't bring his epi-pen.\n\nIn the work place, more responsibility is placed on the worker to take care of themselves.\n\nSchools are set up to care for the students, they are responsible so if anything happens, they are responsible.\n\nWorkplaces aren't responsible for workers (in most situations).",
"Chances are any schools you have with a ban on peanuts have at least one student with an allergy currently attending them.",
"Schools are public institutions. In most cases you have no choice but to go there.\n\nA business is a private institution. They can, as long as it doesn't violate a law, do whatever they want. You are not required to be there, but rather choose to be there.",
"The first time I encountered the same question was this: \"Why is it illegal to passed stopped school buses, but not regular buses?\" Society generally protects kids from things it expects adults to be able to handle.\n\nThere may be different rates of peanut allergies between different age groups. I don't know about that. But I doubt that rates would be the real reason.",
"Kids will hand each other things all the time and not even discuss what they are and then consume it. \n\nAdults are like, \"Is that a fucking peanut, I don't want that.\"",
"Sometimes kids grow out of allergies. Schools are also responsible for the safety of the kids. It's a liability thing. But also, kids are kids. Hopefully, an adult with severe allergies will be more conscious of the issue and more careful than a 10 year old. Also, hopefully, adults working with someone who is allergic will be more aware of what that means and be more careful as a result. Hopefully. It's also a lot harder to police what adults eat in a workplace than it is to police what kids eat at school. Cross contamination would still be an issue though. I don't doubt there are some offices out there that are peanut free though if someone works there who is highly sensitive. But it would be by choice."
]
}
|
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[] |
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[],
[],
[],
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[
"http://www.businessinsider.com/accidental-death-more-likely-than-allergy-death-2014-1"
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[],
[]
] |
||
bbet2c
|
if the sponge is dirty, how do your dishes become clean?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bbet2c/eli5_if_the_sponge_is_dirty_how_do_your_dishes/
|
{
"a_id": [
"ekieacz",
"ekikiz1"
],
"score": [
4,
2
],
"text": [
"Plenty of studies on the bacteria levels in sponges, and the ways to sanitizer them such as putting a squeezed out sponge in a microwave for 10-15 seconds to superheat the bacteria.\n\nA sponge mostly works to mechanically remove food particles from the plate, the soap will break up proteins and fats, the hot water will rinse it off. And any remaining bacteria on the plates will die of starvation and no water.",
"There are two types of \"dirty\":\n\n1. Stuff stuck to the dishes.\n\n2. Bacteria and other nasties on the surface of the dishes.\n\nYou should be using soap or sanitizer to clean #2. However, nasties can hide from sanitizer in the nooks and crannies of #1, so an important part of cleaning something is also removing the hiding places.\n\nThe sponge's jobs are both to remove the stuff stuck to the dish, and to distribute the sanitizer. If there are bacteria in your sponge, the sanitizer on the sponge deals with it the same way it deals with it on the dish. However, your sponge *can* be dirty enough to still cause problems, so replace them regularly.\n\n---\n\nOn a related note, this is why cloudy or brown water is *never* safe to drink, regardless of how much chlorine or iodine you put in it. You need to filter out the \"stuff\" before you can be sure you can kill all the \"nasties\"."
]
}
|
[] |
[] |
[
[],
[]
] |
||
4yfhz7
|
What would happen if a major economy, like the United States, decided to cut off its physical borders and disallow material trade?
|
(I'm trying to keep this question as politically-neutral as possible, and I hope the answers will be the same.)
What would happen if the US became fully isolationist. No immigration or emigration, no import or export of goods or products.
Suppose people and businesses were given enough time (whatever that would mean) to prepare for this transition. It's not like aliens drop a dome over the country without warning.
Would the country/economy be able to sustain itself? Who would do the work that used to be outsourced overseas? What would happen to the products we used to sell overseas?
Also, assume that Internet and other telecommunications still function internationally. We're just not trading with other countries anymore.
|
askscience
|
https://www.reddit.com/r/askscience/comments/4yfhz7/what_would_happen_if_a_major_economy_like_the/
|
{
"a_id": [
"d6ojk69",
"d6xymyo"
],
"score": [
2,
2
],
"text": [
"That's an insanely broad question, so I'll take just one part of it.\n\nDiscussing the Internet, absolutely, it would actually continue to work quite well. Obviously, if there were no cross-border links, no traffic from outside the country would make it in. Traffic from inside would not make it out.\n\nThe internet is fundamentally a distributed, self-healing network. It's designed to route around problems and gaps. Certainly, there would need to be some adjustment and some border areas (like some parts of Canada) that connect exclusively, or primarily through the US would need to change the way they transmit data, but on the whole, things would work fine.\n\nCentralized services like the DNS system would continue to function. DNS records are distributed and root DNS servers are scattered throughout the world, however some of the fundamental organizations that control the policies surrounding DNS and IP address allocation are based in the US, so there would be a period of other countries hashing out which parts of the system would be controlled by which groups, though I don't think it would cause a wide-scale, network-layer outage.\n\nOn the other hand, many providers and services would struggle. Google, for example, might have a challenge on their hands to engineer a system that worked both inside and outside the US. As an American company, assuming Google were to cease operation in all other countries (this is weird, because a substantial fraction of Googles servers are actually outside the US), then the world would need to come up with new search engines, although inside the US, it might still be OK.\n\nIn all, it would be functional, but a bit of a mess to sort out all of the broken ends.\n\nAs for the political topics, that probably needs left to someone else, although what you're asking is *highly* theoretical.",
"As certain industries are excluded from the US economy, domestic industry will begin to produce the goods and services required in the pursuit of profit (such is capitalism). I suppose this equates to an extreme example of protectionism, which economists largely agree to have a negative effect on the economy as a whole. Although employment can be bolstered by the creation of increased domestic demand, competition economy wide is reduced as foreign competitors, as well as the ability to specialize, are negated, leading to a decrease in the general quality and variety of goods and services available to the public. The main concern though is that the US is not energy self-sufficient, meaning that without imported oil in the main, the price of energy will sky-rocket, leading to serious inflation that would more than likely cripple the economy before anything else did. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
1efo6l
|
what happens if you're not a citizen of any country?
|
Got me curious, if I lost or got rid of citizenship to a country what would I identify myself as?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1efo6l/eli5_what_happens_if_youre_not_a_citizen_of_any/
|
{
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"c9zs9rg",
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"c9zvj82",
"c9zw4fy"
],
"score": [
19,
77,
12,
52,
10,
4
],
"text": [
"You could identify yourself as whatever you want to. From the few cases available to read on Wikipedia, it seems you just get bogged down in finding a place to take you. Some Americans who renounced their citizenships while abroad either got kicked out of the country they were living in, or the country they were staying in didn't bother them.\n\n_URL_0_",
"Well, [this movie](_URL_0_) leads me to believe that you sit in an airport...",
"If you're from any of the more developed nations, you probably can't lose your citizenship. Most governments refuse to allow voluntary renunciation or the involuntary removal of citizenship unless the person already has another. \n\nAs an example, the US State Department will not allow a US citizen to voluntarily renounce US citizenship unless it can be demonstrated that the person already has some other citizenship to fall back on.\n\nThe problems that come along with statelessness are pretty serious, and it's not at all a situation you want to find yourself in. You can't travel, can't work, and can't do pretty much anything at all. Whichever country you find yourself stuck in is most likely going to be more concerned with getting you to leave than with helping you. ",
"Nothing happens. I used to be a person with no citizenship. My family renounced their Soviet citizenship in 1990 and moved to Finland, and it took us about 8 years to gain Finnish citizenship. So we had \"[Alien's Passports](_URL_0_)\". Basically the host country grants you a residence permit which, in Europe's case, allows you to move visa-free within the European Shengen area. \n\nSome coutries do have a problem with alien's passports, and don't grant visas to people without citizenship, but most don't have that problem. Border formalities can also take up more time than with a usual passport.",
"Would be cool if you were, you know, \"free\"...",
"Buddy of mine immigrated to the US as a kid from the Soviet Union as a legal resident in the 80's. Then the Soviet Union dissolved and he was a legal resident of the US and a citizen of nowhere. He traveled around with his old Soviet passport. He's now an american citizen."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Statelessness#United_States"
],
[
"http://en.wikipedia.org/wiki/The_Terminal"
],
[],
[
"http://www.migri.fi/asylum_in_finland/applying_for_asylum/obtaining_a_travel_document/aliens_passport"
],
[],
[]
] |
|
3ewpqv
|
if i buy a software or a pc-game and upon installation i decide that i do not agree with the eula can i return the package and have my money back?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3ewpqv/eli5_if_i_buy_a_software_or_a_pcgame_and_upon/
|
{
"a_id": [
"ctj3ajj"
],
"score": [
4
],
"text": [
"Usually, the EULA will state that if you disagree with the it, take it back to the store for a refund. \n\nUsually the store will refuse the refund as you had to open the package to read the EULA. At this point, you can do what others have done: Get a lawyer and force the issue or accept the loss ... good luck.\n\nFor more fun, read:\n_URL_0_\n\nedit: or this link: \n_URL_1_"
]
}
|
[] |
[] |
[
[
"https://www.eff.org/wp/dangerous-terms-users-guide-eulas",
"https://wiki.fsfe.org/WindowsTaxRefund"
]
] |
||
2x9cmf
|
Roman historians- What were the General's daily routine like?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2x9cmf/roman_historians_what_were_the_generals_daily/
|
{
"a_id": [
"coyvj7x"
],
"score": [
6
],
"text": [
"As far as my research has come. No one really knows, this might be because General's don't want to document about what they did after they woke up in the morning before having breakfast. They want to write about their heroic conquests so they can earn gravitas amongst the populace and support in the senate. Marius wasn't concerned that people in Rome didn't know what he ate for breakfast, neither did Caesar, Augustus, Africanus etc.\n\nSorry for the fairly brief explanation, my computer is in repair, so I'm on mobile. It's difficult to make long and drawn out explanations."
]
}
|
[] |
[] |
[
[]
] |
||
2kzm1v
|
A roman emperor (who's name I forgot) reportedly dressed in women's clothes; was this seen as a 'statement' on gender/sexual orientation, or rather an unusual sense of fashion?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2kzm1v/a_roman_emperor_whos_name_i_forgot_reportedly/
|
{
"a_id": [
"clq3147",
"clq64f2"
],
"score": [
46,
3
],
"text": [
"I believe you are referring to Elagabalus. Elagabalus was an interesting fellow. He sometimes rode in a chariot pulled by naked women. He was extravagant in every way. There is speculation that he was transgender although I haven't found a definitive source on that. According to *The Crimes Of Elagabalus* by Icks (2012) Elagabalus sought out a way to medically change his genitalia, so there is speculation that this is why he dressed as a woman (he also sought to emulate the courtesans he hung out with). According to *The Manly Eunuch\nMasculinity, Gender Ambiguity, and Christian Ideology in Late Antiquity* by Kuefler (2001), his tendency to dress in women's clothing could have been a symbol of his extravagance and his connections to eastern fashion traditions. Specifically, he dressed in garments made entirely of silk, which was typically associated with women at the time, and he introduced fashion that was new to Rome (which isn't too surprising in a way, as he was of Syrian lineage). So it is possible that he wasn't exactly cross-dressing but rather dressing in a style that was considered effeminate in his specific time and place. ",
"Another one was Caligula, he didn't always do it but he was known to sometimes. We get that along with piles of other fun gossip about him from Suetonius, who doesn't go into detail about what he means. It wasn't taken as a statement, at least as Suetonius records, but just as Caligula being a wacky dude who flouted all morals, values, and decency. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
3lpeho
|
the logistics of the legality of marriage from state to state in the united states
|
So I was thinking about this: before the SC ruling on gay marriage, there was speculation that some states would not legally recognize those marriages performed in states that gay marriage is legal. How is that even possible? Do you technically have to get legally remarried or reapply for a licence if you move to a different state?
I find it odd that marriage is not nationally/federally organized, considering how important that information is for taxation purposes.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3lpeho/eli5_the_logistics_of_the_legality_of_marriage/
|
{
"a_id": [
"cv853el"
],
"score": [
2
],
"text": [
"In order to get married, you need license from the county courthouse. Between that, and paperwork signed by you and your witnesses and filed with the courthouse, that's what makes a marriage legal. (In most places, at least -- common-law marriages are something else entirely.) \n\nNow you don't have to reapply for that paperwork if you change states -- most states have reciprocal agreements with other states. The only time when it's a problem is when (like now) you have states disagreeing with each other over who can be married; same problem as back in the 1950s and 1960s with interracial marriages. "
]
}
|
[] |
[] |
[
[]
] |
|
51glta
|
Why did Saddam Hussein invade Iran in 1980?
|
What were his motivations for starting a war that would prove to be so costly?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/51glta/why_did_saddam_hussein_invade_iran_in_1980/
|
{
"a_id": [
"d7c6buk"
],
"score": [
31
],
"text": [
"From [an earlier answer of mine](_URL_0_)\n\n**Part I**\n\nAlthough it is tempting to reduce the war's origins to an atavistic land grab by an opportunistic Saddam Hussein, and this certainly was an important factor, the Iran-Iraq War had multiple well-springs. Iran-Iraq relations were characterized by tensions from the establishment of Iraq in 1931 and these tensions periodically escalated into border clashes and diplomatic attacks on the other. But beyond these long-term historical causes, much of the groundwork for Iraq's invasion was laid in the 1970s. \n\nOne of the major underlying *casus belli* was the division of the issue of sovereignty over the Shatt al-Arab waterway that bisects the southern Iran-Iraq border. Control of these waters, and the right to extract tolls and other economic concessions, had been a bone of contention between Iraq and Iran for decades and the diplomatic treaties resolving the issue had a very short shelf-life. The discovery of oil in the region, as well as the importance of the waterway for the export of oil out of both countries, exacerbated the tensions between the two neighbors. The latest diplomatic arrangement over Shatt al-Arab, the Algiers Accord of 1975, was somewhat favorable to the Shah and was a diplomatic humiliation of Baathist Iraq. Both sides pledged non-interference in the domestic affairs of the other and the Shah's negotiators succeeded in getting the placement of the partition line of Shatt al-Arab according to the 1913 Constantinople Protocol. \n\nIraq signed this accord after pressure from fighting Kurdish irredentists in Kirkuk, which in 1974 had become something of a proxy war between Israel, Iran, the US, and Iraq with the former all giving support to Kurdish separatists. Although both the Iranians and the US officials were alarmed at the prospect of escalating their proxy war in Kurdistan as such escalation could lead to either a full war or further drive the Iraqis into the Soviet camp, the signing of a treaty was a public diplomatic setback for the emerging dictatorship of Sadaam. Iran, with the apparent blessing of the US and with Israeli collusion, had interfered with Iraqi domestic politics and paid no apparent penalty. Beneath the cordiality of post-Algiers Iran-Iraq relations, the Iraqi state sought to acquire more weaponry and built up diplomatic connections outside the superpowers to better counteract the lavishly-equipped forces of the Shah. Less than a week before the official invasion of Iraq in 22 September 1980, Saddam unilaterally abrogated the Algiers Accord and publicly declared that:\n\n > the legal status of the Shatt al-Arab must return to what it has always been historically, and what it should never have stopped being, that is to say an Arab river that allows Iraq to enjoy all the rights ensuing from full sovereignty.\n\nSadaam's abrogation of the treaty was not only a diplomatic provocation towards the nascent Islamic Republic, but also a statement outlining the somewhat nebulous pan-Arab goals of Iraq's war of choice. The Algiers Accord fit into a larger pattern in which Iraq had been diplomatically sidelined by the major regional and global powers in the 1970s. Iraq's participation in the 1973 Yom Kippur War and its sponsorship of various Palestinian armed groups had won it very few friends in the West and not reaped many rewards in the Middle East. The Syrian Ba'athist President Hafez al-Assad had emerged as the Soviet's most favored partner in the region and Iraq-Syrian competition and diplomatic sniping at each other was one of the hallmarks of 1970s Middle East diplomacy. But the Camp David Agreement had given the Iraqis an unprecedented opportunity to again take up the flag of pan-Arabism as Egypt's peace with Israel made Sadat a pariah among a large swath of Arab public opinion. This opportunistic attempt to revive pan-Arabism gained even more currency with the advent of the Islamic Revolution in Iran and the ascent of Khomeini, which frightened a number of the Gulf oil states with the spectre of Shi'a irredentism. By virtue of geography, Iraq was well-placed to present itself as the champion of the Arab world against the Persians, but also place itself ahead of Syria as the paladin of progressive Arab politics against Islamism. \n\nYet there was a strong domestic component to the Iraqi post-Revolutionary hardline towards the new regime. The Revolution coincided with Saddam's increasing monopolization of power inside Iraq and the cementing of Ba'athist political hegemony in the country. In early 1979, Saddam had made the Shi'a Dawa party illegal, and while this was partly a reaction to the Revolution, it was part of a larger policy of formally outlawing other rival parties like the Iraqi Communist Party (ICP). The prominence of Saddam's cult of personality also began in this period and both became frequent targets for invective in Tehran against the Saddam regime. Refugees from the Dawa Party found a haven in Iran and Khomeini's speeches against Iraq placed Iraq as one of the Revolution's chief secular enemies. There was a fear, either real or manufactured by Saddam's security forces, of Iranian-sponsored terrorism inside Iraq. In April 1980 Tariq Aziz survived a bombing attack at Baghdad University and other homemade bombs went off inside the city. Iraq denounced the attack, which led Tehran to double-down on its anti-Ba'athist invective. For example, Iranian President Abol Hassan Bani-Sadr denounced Ba'athism as \"no more than an amalgamation of Nazi, Fascist, and Marxist doctrines.\" \n\nThe continued presence of the Revolutionary government underscored the need for Iraq to intervene directly. There had been several coup attempts against the Iranian regime, most notably one centered around air force in July 1980, but the Republic had been able to thwart them all. As Saddam made the decision for war, he shopped the idea around the region to bolster support for both an Iraqi invasion, seize oil-rich regions along the Shatt-al-Arab, and to set up a new, Iraqi-dependent regime in Tehran. For its part, Islamist hardliners in Tehran were no less willing to tone down the anti-Iraqi rhetoric and war with Iraq became accepted as something of a strategic inevitability and a possible boon as it would shore up the Revolution. The Iran-Iraq border became the sight of various pinprick attacks on both sides in the year prior to the Iraqi invasion and cross-border incursions would feature heavily in Saddam's public justifications for the invasion. The Iraqi army's officer corps, although now heavily composed of Ba'athist loyalists, also began to expect the inevitability of an Iran-Iraq war, although it accomplished incredibly little in terms of actual strategic planning for hostilities. As Iraqi Republican Guard general Ra'ad al-Hamdani explained in a post-Iraqi Freedom interview: \n\n > the decision to go to war with Iran rested on several assumptions. the first was to prevent the exportation of the Iranian revolution to Iraq. the second was that the new Iranian army at the time was still in the early stages of formation, while the shah’s army was dissolving. This presented an opportunity to attack when [the Iranians] were weak. The Iraqi leadership figured that if the Iraqi armies advanced approximately 10–20 kilometers deep into Iran along the borders, Khomeini would have to send [Iranian] forces from the surrounding area of Tehran to the borders. this would leave Tehran exposed, and give the opportunity to the Mehdi Bazargan group [one of the Iranian factions opposed to the hardline turn of Khomeini] to revolt against the religious leadership and gain control of Tehran. So the idea was to bring the militia out of Tehran to weaken the revolution for a counterrevolution.\n\nThe generally poor preparation of the Iraqi military gave the Iranians much needed breathing-space to organize a defense and shore up the regime at home. Ironically, and somewhat fittingly, the Iranian invasion only furthered Iraqi diplomatic isolation. The Soviets were alarmed by the Iraqi actions as they saw it as playing into the hands of the Iranian Islamist factions at the expense of Tudeh, the Iranian Communist Party. Saddam's rivalry with Syria, clamping down on the ICP and rhetoric about pan-Arabism had already soured Iraqi-Soviet relations, especially since Iraq had publicly critiqued the Soviet Afghan invasion. The Soviets declared an embargo on Iraqi arms and refused to honor existing contracts, which became a major issue as the Iraqi offensive stalled and ate up existing stocks of munitions and equipment. "
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/4g8gz9/why_did_iraq_attack_iran_right_after_its/"
]
] |
|
39pe05
|
What are the oldest Mongolian tribes that are still nomadic?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/39pe05/what_are_the_oldest_mongolian_tribes_that_are/
|
{
"a_id": [
"cs5axyk",
"cs5m0zb"
],
"score": [
6,
3
],
"text": [
"Most of Mongolians outside of Ulaanbataar are nomadic. What is your question?",
"This submission has been removed because it violates our ['20-Year Rule'](_URL_0_). To discourage off-topic discussions of current events, questions, answers and all other comments must be confined to events that happened 20 years ago or more."
]
}
|
[] |
[] |
[
[],
[
"http://www.reddit.com/r/AskHistorians/wiki/rules#wiki_no_current_events"
]
] |
||
2dihqa
|
what would happen if we cured cancer?
|
Say we find a cure for all the types of cancer. Would we see a spike in population growth? Would we see other diseases become more prevelant?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2dihqa/eli5_what_would_happen_if_we_cured_cancer/
|
{
"a_id": [
"cjpvdgw"
],
"score": [
3
],
"text": [
"Lol, i was wondering this just yesterday. If we cured cancer and heart disease, what's the next big thing that old people would die of, and at what typical age? "
]
}
|
[] |
[] |
[
[]
] |
|
cf2h11
|
why do males typically have longer eyelashes than females?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/cf2h11/eli5_why_do_males_typically_have_longer_eyelashes/
|
{
"a_id": [
"eu6rulg",
"eu6rupe",
"eu7phxz"
],
"score": [
21,
6,
3
],
"text": [
"Males on average are hairier than women, so their lashes too are thicker and appear longer (on average)",
"Evolution, men in general naturally have thicker hair than women. This is no different for eyelashes.",
"Those serve a purpose of incoming water barriers (where eyebrows are first barrier for raindrops from above, serving same function but in bigger scale, and eyes are buried into the skull, thus shape of the face helps it as well), and there is thousands of years of difference in what sex was specialized to go hunting outside to the rain and what sex was in cave parenting new generation. This specialization is still present in our genes and even though nowadays is not really useful for continuing of this evolutionary advantage, it is still big part what makes males and females different (other examples are basic size, strength, temperature handling, and even the *way* of using brain for same goals). And because those differences aren't really usable anymore in most cases, they probably will degenerate into one form same for both sexes over time.\n\nYou might be able to actually test it on yourself. If you keep your head perfectly straight and place a shower head over yourself, you should be getting total minimum of water into your eyes, most of it will be shifted by eyebrows, and eyelashes should be able to catch the remaining droplets. The shape of the eye also helps to this effect, as water tends to stick to the surfaces (surface tension) so it will rather roll on curved sides of eye towards the nose or the eye corner, than it would go directly down into the eye.\n\nAdditionally, they also serve a purpose of barrier for other particles, let's say insects. Again, that's what you have to deal with when being outside. And if you actually get something into the eye and it will tear up, they will help to move the water outside the eye way faster than if you had no eyelashes. \n\nCheck out that ears have quite similar protection against such incoming water, but mostly just by the shape of them.\n\nIt is definitive evolutional advantage to be able to see well in bad weather or in general, at all time. If you hunt, you need to have full attention 100% of time, because even single second of lost attention means no food today and possibly extinction of your tribe."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
6uvyzs
|
does the water included in a cup of tea count towards the 2 litres a day you're supposed to drink?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6uvyzs/eli5_does_the_water_included_in_a_cup_of_tea/
|
{
"a_id": [
"dlvs78l",
"dlvv31s"
],
"score": [
11,
2
],
"text": [
"Absolutely. Many people point out that tea is a diuretic and makes you urinate more. However it does not make you urinate more than the volume of the tea you've drunk, so there's a net gain in water in your system. \n\nAlso bear in mind that the figure of \"2 litres of water\" was never based on any sound research, it was more or less a \"2 litres sounds and feels about right\" statement made years ago that people have latched onto. \n\nThat figure, unsound though it is, doesn't just refer to water you drink. It includes water ingested from all sources, including your food, beer, tea, coffee etc. ",
"Caffiene is a diuretic, but a study this study on 50 men who drink 3 to 6 cups of coffee a day showed that coffee provides similar hydrating qualities as water. One study only 50 people, and on coffee not tea. In a separate study, coffee didnt effect the hydration of athletes either. It is understood that if you regularly drink coffee you build up a tolerance to the diuretic.\n\n_URL_1_\n\n_URL_0_\n\nThe food board did recommend that people needed 2.5 liters of water a day, but in the next sentence it says most of that water is contained in prepared food. So you don't need to drink much more water to reach the 2.5 liters. Studies on drinking more water doesn't show much benefit."
]
}
|
[] |
[] |
[
[],
[
"https://www.ncbi.nlm.nih.gov/pubmed/15467100",
"http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0084154"
]
] |
||
1z8eho
|
does your car heater get warmer faster if you turn it all the way up to high, or if you use the "auto" setting that waits for the heater to warm up.
|
I have always turned heat and fan all the way up because I think it is faster...
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1z8eho/eli5_does_your_car_heater_get_warmer_faster_if/
|
{
"a_id": [
"cfrgjpf",
"cfrhqrk"
],
"score": [
2,
3
],
"text": [
"the auto setting. Blasting the air will only keep the heating system cooler longer and the moving air will make you colder. However, you might want to turn it on defrost on low to help defrost your window if you live in a climate that cold.",
"Most heaters use heat from cooling system of the engine. It takes several minutes for the engine to heat up enough for the heater to work. In 'Auto', the fans will only run slow until there is some warmth for them to distribute.\n\nThe system will also run the fans quickly as long as the temperature in the car is below the desired setting. So the fan will run at high speed until the car is warm.\n\nSo Auto is probably the best place to leave it, permanently."
]
}
|
[] |
[] |
[
[],
[]
] |
|
1bsv79
|
why are film studios trying to get google to take down their own dmca infringement notices? what were those notices doing in the first place?
|
_URL_0_
I just don't understand what's going on, what the different parties' (film studios, google) motives are, what their means of achieving whatever goals, etc.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1bsv79/eli5_why_are_film_studios_trying_to_get_google_to/
|
{
"a_id": [
"c99sev0"
],
"score": [
6
],
"text": [
"It's hard to be certain, but the article does posit a guess which is in line with what I would expect. It's probably an automated bot problem.\n\nRecently, Apple put out an app for the iPhone that can tell you the name of the song by listening to it. This is because they basically have a library of music and are able to match the sound of the music to the library and find the name of the song. \n\nIn the same way, many film studios have bots (automated programs) that can either listen to music or view videos and compare them to their own library of music and movies. When the bot finds a video on YouTube, for example, that contains a movie or sound recording in their library, the bot automatically sends a takedown request to YouTube (which is owned by Google). (This is why you will see things on YouTube like news reports and the like that are backwards - it looks like you are watching it in the mirror. The bots specifically looks for the video in their library and when it is reversed, the bot can't match it).\n\nThe problem is, it's not illegal to submit content to YouTube if you own it. Some studios are legitimately posting their own content, but then their own bots find them and report them. "
]
}
|
[] |
[
"http://www.geekosystem.com/copyright-holders-recursive-google-request/"
] |
[
[]
] |
|
1qux92
|
why is being a lawyer drastically different from other professions?
|
Particularly law school
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1qux92/eli5why_is_being_a_lawyer_drastically_different/
|
{
"a_id": [
"cdgr2jf",
"cdgrdq4"
],
"score": [
5,
2
],
"text": [
"It's not really unique -- doctors of all sorts have to go through a similar process. Basically what it comes down to is that they are jobs that require a great amount of trust from the customers -- doctors and lawyers are both in a position to *really* fuck over their customers without them realizing it. They go to school and are taught in a very intense manner, both because there is a lot to know, and also because it is very important that they understand it well, because it's their role to understand it so everyone doesn't have to.",
"I think you need to specify what you mean further. In what way is it drastically different?"
]
}
|
[] |
[] |
[
[],
[]
] |
|
15uuy3
|
how a consumption tax could possibly work and the arguments against it.
|
From how it was presented to me, it seems like the most efficient way to target the wealthy, rather than income or capital gains taxes. What are the downsides, other than increased prices?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/15uuy3/eli5_how_a_consumption_tax_could_possibly_work/
|
{
"a_id": [
"c7q0e8a"
],
"score": [
6
],
"text": [
"Right now, the most popular consumption tax proposal is called the FairTax. There would be a 23% (inclusive) tax on all new goods, and there would be no income taxes, no tax on used goods, no tax on capital gains, etc. The 23% tax rate is estimated to collect the same amount of revenue as our current tax code.\n\nBut, the tax is progressive. Part of the FairTax is that everyone would get a monthly check from the government to basically un-tax the amount of money you would have to spend on basic necessities. They call this the *pre-bate* (like a rebate, but it comes before you buy stuff). So, the folks that don't have *any* income would actually be getting free money. The low-income folks would even-out to about paying 0% in taxes. The middle-income folks would pay somewhere between 0 and 23%. And the highest income folks would be paying just under 23%.\n\nIllegal aliens, tourists, and other people that don't get the pre-bate would be paying the full 23%.\n\nNow, this has it's pro's and con's, just like any other tax plan. But I think I've outlined the basic features of the most-popular consumption-tax proposal."
]
}
|
[] |
[] |
[
[]
] |
|
3y807a
|
why do all of the east asian ethnicities seem to hate each other?
|
I understand the cause of animosity between Japanese - Chinese - Koreans, but what about all the other ethnic groups?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3y807a/eli5_why_do_all_of_the_east_asian_ethnicities/
|
{
"a_id": [
"cynsutn",
"cybatag",
"cybaz9a",
"cybceq3",
"cybgkiz",
"cybhu72",
"cybj84x",
"cybkruh",
"cybl6xg"
],
"score": [
2,
2,
127,
9,
6,
2,
12,
10,
12
],
"text": [
"Well, imagine what it would be like if Germany didn't admit their crime and kept their facism. Imagine them saying \"Auschwitz is a lie\" or \"F*** Jews and other nations\". Most of us Koreans are fine with individual Japanese. We don't go up to them and say \"Hey! We hate you\". But when it comes to historical facts, people have this.. thing about Japan as a nation. It USED to be nation but after seeing all these radical Japanese right wings, people began to gave up their hopes and those surveys usually show about 40~60% of Japanese people acting in accordance to Abe's cabinet, or act in accordance to imperialism.\n\nAs for Chinese, we don't actually have much hatred against them... Except when it comes to illegal fishing and how they treat North Korean defectors.\n\nBut of course, this is just my opinion. It can be different and there are always those idiots who just hate 'everyone' with and without a reason. Hope this clearifies your question :)",
"The only real hate is against the Japanese people from most, if not all the East Asian ethnicities, because of the World War 2 atrocities committed. A lot of \"hate\" you see among Asian ethnicities to other Asian ethnicities, excluding Japan, stem from narcissism and inferiority or superiority complex. \n\n\n",
"They don't hate each other (well, not too much). They all hate Japan. During the second world war, little of east asia was left untouched by them, and they committed war crimes left right and center everywhere they went as if it was their god given responsibility. The animosity continues to this day partly because the government actively stokes it (in the case of the PRC, for example) but mostly because of the modern Japanese government's refusal to acknowledge said crimes (imagine if Merkel claimed the Holocaust only had a few dozen victims and regularly visited the grave of Heinrich Himmler to pay respects). \n\nVarious amounts of animosity remain between the rest of the east asian countries for various cultural, political, and historical reasons, but it's all chump change compared to how everybody feels about Japan. ",
"Japan invaded and occupied huge swaths of east and southeast Asia before and during WWII, and, as others have noted, viciously brutalized enemy combatants and civilians alike. People who lived through these events are now quite elderly, but certainly most Koreans over 40 grew up with parents or grandparents who suffered under the Japanese. This accounts for much of the enmity toward Japan, at least with respect to Koreans and Chinese. \n\nI never saw much in the way of prejudice involving other Asian groups, but I suspect that Asians from more developed nations (e.g. Japan, Korea, Taiwan, and Singapore) may have some feelings of contempt for Asians from less developed countries like Vietnam and Cambodia, and because Asians from more tropical climates tend to have darker skin, there may in fact be some color prejudice. This would be akin to white Americans' dislike of Mexicans. ",
"Quick question relevant to this thread: I've heard often that there's a lot of racism in Japan against Korean people, is this true and why?",
"The reason is they all think they're better than each other....and worse, they all know that.\n\nWatching sporting competitions in asia is fun...\n\n",
"I'm Chinese American and my parents have some animosity for Japan. I go by yoshi among my friends and they fucking hate it because it's \"japanese\". A lot of it has to do with the rape of nanking and the atrocities there. The Japanese were in dicks in general during WWII to entirety of eastern asia, committing war crimes and such. Thats why there's alot of hate towards Japan.",
"Everyone hates everyone. White people are unfairly portrayed as the exclusively racist race, but truth is, humans in general are prejudice against those different than them. East Asia has several very distinct cultures in a relatively small geographical area, so there's a concentration of differences.",
"Oh the Catholics hate the Protestants, \nand the Protestants hate the Catholics, \nand the Hindus hate the Moslems, \nand everybody hates the Jews.\n\nIn general, everybody hates, to an extent, his neighbors. They have a thousand years of history -- invasion and counter-invasion, war and atrocity -- that they can whip out whenever they feel the need to blame someone else for their troubles.\n\nIn general, smaller countries hate larger countries. Cambodians hate their much larger neighbors, Vietnam and Thailand. The Vietnamese and Thai don't think about tiny Cambodia much but the Thai hate the Burmese and Vietnamese hate the Chinese. The Chinese are largely unaware of the Vietnamese and hate the Japanese.\n"
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
|
10cy0f
|
why does u.s. has different spelling, words and measurements than the other countries?
|
Question 1: Why does the U.S. use inches, pounds, miles etc and other countries use kilograms, centimeter etc?
Question 2: Why does the U.S. call football "soccer"?
Question 3: Why does the U.S. have a different spelling of words such as color or honor?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/10cy0f/eli5_why_does_us_has_different_spelling_words_and/
|
{
"a_id": [
"c6ce5r3",
"c6ckz7r",
"c6coy38"
],
"score": [
7,
2,
2
],
"text": [
" > Question 1: Why does the U.S. use inches, pounds, miles etc and other countries use kilograms, centimeter etc?\n\nWe're used to the system, and there hasn't been a large-scale movement to change it. Even in countries where the metric system has replaced imperial, you'll often see a mix of imperial and metric - in the UK, for instance, speed limits are given in MPH.\n\n > Question 2: Why does the U.S. call football \"soccer\"?\n\nIt's derived from \"association football\". It's actually a term created by the British, and it's common in non-UK English-speaking countries (Australia, New Zealand, Ireland, Canada, and South Africa all use it).\n\n > Question 3: Why does the U.S. have a different spelling of words such as color or honor?\n\nNoah Webster wrote a dictionary back in 1828 that was especially popular in America that simplified some spellings, like -our to -or, and making words like \"centre\" into \"center\". ",
"American football and association football are related sports. Football is usually the name for the most popular version of the sport in the area. Soccer comes from the word association.\n\nThe Americans changed the spellings of a bunch of words both to be different than the Brits and also to simplify spelling somewhat. Most of the changes didn't catch on though.",
"Wow. Nobody has said \"cuz 'Murica\" yet.\n\nI'm so proud of us!"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
2a86ao
|
Would a herbivore consume meat if it had no other food available to survive?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2a86ao/would_a_herbivore_consume_meat_if_it_had_no_other/
|
{
"a_id": [
"cishccq"
],
"score": [
10
],
"text": [
"Yes, to a certain extent; many large herbivores like cows and elephants are continually accidentally eating little bits of meat in the form of snails and other bugs that get into their actual food; mountain gorillas eat exclusively leaf and fruit material most of the year and supplement their diets with insects when their seasonal plant food is unavailable.\n\nHowever, most herbivores have digestive systems specialised for dealing with fibrous, low-protein, low-fat plant food. They often lack sufficient enzymes to break down the amount of fats and proteins in meat, and are used to keeping their food in their digestive tracts for a longer time than carnivores. For these reasons, eating meat can make some herbivores sick, and animals with very specialised diets like kangaroos can even get sick from eating low-fiber plant material like white bread.\n\nDespite this, small amounts of extra nitrogen and other minerals can be beneficial for herbivores on restrictive diets, as nitrogen is an important precursor to protein. For this reason, urea from livestock of different species is sometimes added to fodder for dairy cows and other herbivorous \"farm animals\" that need to increase their protein output cheaply and quickly.\n\n**TL;DR: yes but only a little bit.**"
]
}
|
[] |
[] |
[
[]
] |
||
jds1l
|
When I "magnetize" a screwdriver what is exactly going on?
|
askscience
|
http://www.reddit.com/r/askscience/comments/jds1l/when_i_magnetize_a_screwdriver_what_is_exactly/
|
{
"a_id": [
"c2ba75e",
"c2ba75e"
],
"score": [
3,
3
],
"text": [
"On a microscopic scale, a ferromagnetic substance is comprised of tiny little regions called *domains*. The magnetic field of the atoms of within a domain are all aligned in the same direction, but the domains themselves are not coaligned. It is kind of like it is a bunch of tiny magnets pointing different directions all smooshed together.\n\nWhen that substance get magnetized, the domains all line up. But when those domains get agitated, by heat or by vibration, they can get rescrambled. ",
"On a microscopic scale, a ferromagnetic substance is comprised of tiny little regions called *domains*. The magnetic field of the atoms of within a domain are all aligned in the same direction, but the domains themselves are not coaligned. It is kind of like it is a bunch of tiny magnets pointing different directions all smooshed together.\n\nWhen that substance get magnetized, the domains all line up. But when those domains get agitated, by heat or by vibration, they can get rescrambled. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
1j5ago
|
Which historical figures do you suspect were clinically psychopathic or somehow mentally disturbed?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1j5ago/which_historical_figures_do_you_suspect_were/
|
{
"a_id": [
"cbb94lr"
],
"score": [
2
],
"text": [
"Answering this question by definition requires people to speculate. As such, it is not appropriate for this sub."
]
}
|
[] |
[] |
[
[]
] |
||
6ylxse
|
British monarchs and language
|
I've read on wiki that all the monarchs dating back from George I came from same house ( House of Hanover) which was German royal family (right?). Therefore it makes me wonder what language they were using? Since they were German kings then why didnt they impose German language on UK?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/6ylxse/british_monarchs_and_language/
|
{
"a_id": [
"dmodvas"
],
"score": [
2
],
"text": [
"George I is asked by Parliament to take the throne because he is the grandson of Elizabeth Stuart, and great-grandson of James I. More importantly, he's also a Protestant. At this time, the early 1700s, there wasn't yet a German royal family, by the simple fact that Germany wouldn't become a country until 1871 under the auspices of Wilhelm I of Prussia. George is the elector count of Hannover, or technically the Electorate of Brunswick-Lüneburg, a semi-autonomous province of what was then the Holy Roman Empire. Hannover had, in fact, only been an electorate since 1692.\n\nGeorge is invited to take the British throne at a moment of political instability, as the House of Stuart had left no immediate heirs. When George arrives in England, he speaks very little English, and is not immediately popular. Parliament also makes the terms of his coronation contingent on the political separation of Britain and Hannover. It's important to remember that in this context, George and his family are just one small group of Germans. This is neither a political union of states, nor is it the type of complete invasion of 1066 or mass migration of the 6th century. Following the civil war and then the Glorious Revolution of 1688, Parliament was emerging more and more as the ruler of Britain. Teaching the entire country to speak German for the benefit of an increasingly ceremonial monarchy would have been not only politically incredibly unpopular, but also unfeasible."
]
}
|
[] |
[] |
[
[]
] |
|
26pnyo
|
Would you be able to feel particles going through your body?
|
Say someone shoots a proton going at light speed at your skull, would you be unfazed or would the proton go through your skull and you would then die from the proton causing damage.
|
askscience
|
http://www.reddit.com/r/askscience/comments/26pnyo/would_you_be_able_to_feel_particles_going_through/
|
{
"a_id": [
"chtcd14",
"chtcg0g"
],
"score": [
2,
4
],
"text": [
"If it was a single proton, sensually you would be unfazed as it does not nearly have the energy to do actual damage to you. Even if it were a stream of protons at high energy, you wouldn't be able to 'feel' them per se because they're way too small. You would most certainly however feel the side effects of radiation burns and cancer. So don't do it.",
"You are asking 2 different kind of questions, if you could feel it or if you would die from it.\n\nIn order to feel something, it would have to activate a neuron. In theory you could fire some radiation just right so it could trigger the neuron. in reality, walk through a contaminated zone and you feel the effects of radiation like radiation sickness rather than the radiation itself. You are not going to die from a singe proton either, you need a lot, a lot. BTW you have bilions of neutrino's shooting through your body through your life time without you noticing anything."
]
}
|
[] |
[] |
[
[],
[]
] |
|
1xbb19
|
why are tractor-trailer engines designed to last 500,000+ miles while normal car engines rarely go for more than a few hundred-thousand?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1xbb19/eli5why_are_tractortrailer_engines_designed_to/
|
{
"a_id": [
"cf9sauw"
],
"score": [
3
],
"text": [
"Because tractor-trailers are designed for a lot of long-distance hauling. That's pretty much their entire purpose, so their engines are designed around those needs."
]
}
|
[] |
[] |
[
[]
] |
||
3hor5p
|
why linux usb file transfers lightning fast, and windows transfers at a snails pace?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3hor5p/eli5_why_linux_usb_file_transfers_lightning_fast/
|
{
"a_id": [
"cu987md"
],
"score": [
6
],
"text": [
"By default, windows will write to USB drives in a slower, safer way than Linux (no caching). This means that if you remove the drive without unmounting it, the data written to the disk will actually be there. \n\nYou can go into the drive properties in windows to enable write caching to speed up writes to the drive. But always remember to \"eject\" the drive in windows before physically removing it. "
]
}
|
[] |
[] |
[
[]
] |
||
329f3a
|
what is the evolutionary advantage of humans holding on to our waste byproduct for the toilet instead of just letting loose when it's ready?
|
It seems that most animals - invertebrates, birds, fish, mammals alike - all just let loose when the pee/poop is ready to come out. Why do we hold on to it inside our intestines and bladders? Is it social thing because fish, birds, and horses are social creatures and yet they just poop anytime they want?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/329f3a/eli5_what_is_the_evolutionary_advantage_of_humans/
|
{
"a_id": [
"cq93hlu",
"cq93mnp"
],
"score": [
3,
5
],
"text": [
"We're not the only ones to do this. Think about cats and dogs, for instance. The reason is that waste breeds disease. For that reason, it's advantageous to be able to hold it until you're away from the place where you eat/sleep.",
"Most animals don't just poop wherever/whenever they want. Dogs will try to do it far away from a food source, while cats will do it where they can bury it. The reason is that feces spreads disease very easily and taints food/water in contact with it. Some animals are more casual with their pooping -- usually grass-eating herbivores like horses, cows, and rabbits. If you've ever been on a farm you'll know that their feces is a lot less noxious and disease-ridden than human or dog feces so they can afford to be like this.\n\nIf you just pooped wherever you were, your home, bed, family, etc would all be crawling with fecal bacteria, which in large numbers will make you sick at the best of times, god forbid you injure yourself and those bacteria get into the wound. We've evolved to be disgusted by our feces and to want to get away from the stuff, and being able to control when we release it helps us make sure it remains far away from our food and home environment."
]
}
|
[] |
[] |
[
[],
[]
] |
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