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21v76z
|
With all the rumors/hype about sapphire glass in next-gen smartphones, what is the chemical difference between sapphire glass, Gorilla Glass, and "normal" glass?
|
askscience
|
http://www.reddit.com/r/askscience/comments/21v76z/with_all_the_rumorshype_about_sapphire_glass_in/
|
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"Ordinary glass is usually [soda-lime glass](_URL_0_), which is mostly silicon dioxide (~75%), sodium oxide (~13%), calcium oxide (~10%), and minor additions of other elements. It's cheap and easy to work with, but brittle and easily shattered. \n\nBrittle objects are very vulnerable to rapid crack propagation. This makes them much weaker in tension than in compression, since tension pulls cracks open, while compression pushes them shut (note that when you bend something, the object will be partly in compression and partly in tension, so brittle materials are weak in bending as well, breaking at the part that's in tension). One way to make brittle materials like glass stronger is to manufacture them such that residual compressive stress develops at the surface- cracks generally start at points of damage in the surface of the material, and this stress will oppose any tension applied to the object. Gorilla Glass does this through \"ion exchange\"; the glass is submerged in a bath of molten potassium salt, and the potassium ions replace sodium ions in the glass. The potassium ions are larger than the sodium ions they are replacing, so squeezing them into the same space causes residual compressive stress to develop in the glass. This makes it much more resistant to scratching and breakage.\n\nSapphire \"glass\" is just a slab of synthetic sapphire, an aluminum oxide crystal (it's actually crystalline, unlike normal glass, which is amorphous). It is even harder than Gorilla Glass, and thus more difficult to scratch, but unless they manage to induce similar residual compressive stress it could actually be easier to shatter. It's also a lot more energy-intensive to manufacture, and thus more expensive. On the third hand, surface scratches significantly weaken brittle materials, even ones toughened by residual stress, so if a Gorilla Glass screen does pick up a scratch and then gets dropped again it could wind up being easier to shatter than a pristine sapphire crystal. \n\nThe only thing I can think of off the top of my head hard enough to scratch sapphire/corundum/alumina (different names for the same stuff) that's encountered commonly in daily life would be the diamonds in diamond rings. "
]
}
|
[] |
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[
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||
1915zh
|
Is it really appropriate to label the Greek settlements outside of Greece 'colonies'?
|
From the little I've read on the subject, it seems a little anachronistic. Is that fair, or am I nitpicking?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1915zh/is_it_really_appropriate_to_label_the_greek/
|
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"It is an anachronism, in that I dont think the Greeks used the term (I think its latin). But colonising by planting a new settlement in the pattern of the parent settlement via a structure or system (polis) which was alien to the new location, while maintaining contact with the parent, is exactly what the Greeks were largely doing, as were the later colonial powers.",
"Well... they're settlements emerging as the result of a concerted effort by a community in Greece to establish a new community in another land. 'Colony' seems like as good a term as any... I'm at a loss as to what else you could call them, anyway."
]
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|
[] |
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fetfds
|
why do humans cringe? does the same response occur in other animals?
|
What is the reason for such a crippling reaction to uncomfortable social interactions?
EDIT: Thank for the replies so far, I am more wondering from an animal behaviour perspective. Starting to get the sense it is a form of social preservation because you can dissociate yourself from the bad thing.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/fetfds/eli5_why_do_humans_cringe_does_the_same_response/
|
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"There's a lot of things that say humans feel/think that animals can't, and they're still unsure on so much shit. We don't even understand our own brains let alone an animal's. Let alone EVERY animal, when dolphins and chimps are more intelligent than half of Reddit.",
"You react negatively to anything \"out of place\" or something that can impact your social/hierarchical standing. Such discomfort gives you a signal to not do something that can make you an outcast.",
"I’ve tried to condition my dog to not bark at strangers, but she’s a watch dog at heart. If I’m in the room and she barks at a noise outside, she’ll immediately look at me, put her ears back and flinch, then break eye contact and stop barking. A doggy cringe if ever I’ve seen one.\n\nAs for why people or animals might do it, I can only guess. Some mechanism in our brains makes us close our eyes and will this awkward situation to go away. A holdover from our childhoods to close our eyes and deny that object permanence exists so that the cause of our discomfort also no longer exists? An acceptance that we can’t avoid this situation so we close our eyes and brace for impact emotional or physical?",
"If you did something awkward or socially unacceptable, you might be an outcast or kicked out of the tribe. Kicked out of the tribe? No food, no protection, no mating. You die, and so does your bloodline. Cringing is a conditioned survival response.\n\nSame reason it’s so devastating for a child to feel like their parent doesn’t Love them. We’ve evolved to see that as a threat to survival\n\nSource: my parents don’t love me\n\nEdit: in response to your edit, I think most of the same principles apply to animals. I don’t think an animal that doesn’t rely on others of its species to survive would have as much of a cringe response",
"This definitely occurs in animals and humans. \nSee also having your feather's ruffled, birds that actually ruffle their feathers, cats who's hair stands on end. It's can be done without intention, they have the same back crawling feeling of just insecure cringe.",
"Humans are intensely social and we tend to mirror the emotions of who we’re observing. Happy people make you feel happy, angry people make you feel angry, seeing someone get hit in the balls makes everyone around wince and so on. \n\nSo seeing someone get embarrassed causes second hand embarrassment."
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zyxod
|
Why did our immune systems evolve so that we need our meat cooked? (please read description)
|
My question, as stated above is, why do we need our meat cooked? I know it is because we need to get rid of the bacteria, but every other carnivore or omnivore does not need their meat cooked. So why does ours? Why would our immune system evolve so that we need meat to be cooked? Why would it need that extra step to be taken when it is unnecessary?
|
askscience
|
http://www.reddit.com/r/askscience/comments/zyxod/why_did_our_immune_systems_evolve_so_that_we_need/
|
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"We do not need to eat our meat cooked.\n\nDoes it kill bacteria? Yes. But that is an added benefit.\n\nIf you were to eat raw meat straight of the bone right after it was killed, as animal carnivores do, you would not need to worry about bacteria. Bacteria only move in and set up shop and multiply after hours and days.\n\nThe advantages of coking is that you can eat meat after several days, instead of only several hours.\n\nIn addition, cooking makes things more easily digestible, at least at the front end (mechanichal digestion - chewing).",
"We don't need to eat our meat cooked. In fact, we eat raw meat quite often. For example, we eat sushi, sashimi, steak tartare, carpaccio, and many kinds of cured meats like prosciutto and jamón serrano.",
"I wonder if cooked meat has more food calories than uncooked meat? Don't brain cells use a lot of energy?",
"From what I understand, we don't actually need to cook food. Humans cook their food because it aids in breaking down proteins. It helps us feed our energy sucking brain. (Trying to find the source for this)\n\nEdit: [source](_URL_0_)\nSo it seems that we don't *need* to cook our food, but it aided in our evolution.",
"Just one minor nitpick:\n\n > Why would our immune system evolve so that we need meat to be cooked?\n\nEvolution isn't a rational process. If you can you still survive and reproduce with that \"imperfect\" immune system then its fair game."
]
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1sp329
|
if 2-d and 3-d can be drawn on paper (a "3-d" object) then what is the real world and the first dimension?
|
Plus, what about inside black holes?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1sp329/eli5if_2d_and_3d_can_be_drawn_on_paper_a_3d/
|
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"3D isn't drawn on paper. A 2D representation is drawn on paper.\n\n",
"It might *look* 3D because of shading and perspective, but every picture drawn on paper is 2D.",
"Your question makes me really confused. Exactly what is it that you're asking about?\n\nAs for the first dimension: A square drawn on a paper has two dimensions, height and width, right? So then a line is one-dimensional, it only have length (a drawn line physically has a width, but the line represents one dimension).\n\nA 3D-object drawn on a paper is a 2D rendition of a 3D object, it's not actually 3D since you need three actual spatial dimensions (height, width, length) in order for it to be truly three-dimensional. "
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3ct8az
|
why large companies like tyson are not charged with animal cruelty?
|
Even after multiple videos showing evidence of cruelty, why do companies that raise livestock and poultry in a very inhumane manner do not face legal repercussions?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3ct8az/eli5_why_large_companies_like_tyson_are_not/
|
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"Doesn't Tyson own like 40% of the food market?",
"The correct answer: Because it isn't animal cruelty.\n\n\"Animal cruelty\" is what we call **senseless** harm to animals. People who smack their dog on the nose when it pees on the carpet may not be role models for animal care -- but they won't be charged with a crime, because the reason for their action stems from something more than \"Because I want to cause pain and suffering to the animal.\"\n\nLikewise, despite some of the poor conditions that various companies keep animals in, they aren't doing it for the purpose of being cruel to the animals. Rather, the treatment of the animals is a consequence of necessity to create the yields demanded by our meat-loving citizens. Sure, they **could** make things better -- but that means extra costs... extra costs which would make them less competitive against companies who are unwilling to do the same (this is why regulation is sometimes required to force everyone to play by a standard deemed important). And, ultimately, consumers do not want to pay more for those comforts.\n\nSo the reason companies like Tyson are not charged with animal cruelty is simply because they are not committing animal cruelty. If, at some point, someone at Tyson decides to implement a method of causing pain to animals simply because it brings him joy or entertainment... then you'd have a case for animal cruelty.\n\nWeirdly enough, though, the same reason that the poor conditions exist is the reason that you'd never have such a conscious abuse of animals... because such a conscious abuse, itself, would have a cost associated with it, and the company's shareholders would bring an action to stop it just for the sake of profits."
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jdivc
|
Could we build a sustainable society on Antarctica?
|
Ever since the McMurdoc guy's AMA (can't find it now I'm afraid) I've been ridiculously interested in Antarctica. On earth, it is in a sense the final frontier for mankind.
Having played around with the thought of colonising Antarctica in my head for a while, I thought I'd finally go ahead and ask the scientific community here on Reddit. Would it be possible?
I mean I know we already have research colonies established and all, but they're heavily dependent on shipments from the rest of the world. Would it be possible to on Antarctica produce enough energy to maintain some sort of biodome where we could grow food and perhaps even livestock? What kind of power supply would be sustainable in such an environment; solar? Wind?
EDIT: Oh, and on a further note: is it a legal possibility considering the treaties in place regarding who owns Antarctica?
|
askscience
|
http://www.reddit.com/r/askscience/comments/jdivc/could_we_build_a_sustainable_society_on_antarctica/
|
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"From a practical standpoint, you just need sustainable natural power sources. I would imagine a combination of solar and wind, and possibly a type of hydroelectric. With sufficient power, your buildings are heated, your greenhouses are powered, and you could sustain a decent population.\n\nThe real challenges (legal/sovereignty aside) are large-scale fresh water supply and waste disposal systems. I know this because I had family living in Frobisher Bay (the populated area of Baffin Island in the Canadian Arctic) for a few years. You would require a very well planned city design for effective underground water and waste services, which would be very expensive to build and maintain, and even more so to expand. Population control would be another issue altogether, fortunately (or unfortunately), the Canadian Arctic does not have that problem.\n\nIf you're interested in reading up on this, I found what appears to be a decent paper on the topic.\n\n_URL_0_",
"I'd say no - and not because of resource availability.\n\nIt's my understanding that the outposts in Antarctica have to be repositioned as the ice moves towards the ocean, and it's not by small amounts, either.",
"Physically? Most likely. Legally? [No.](_URL_0_)",
"I've been thinking about colonizing Antarctica for the past few years, so this post excites me.\n\nThe key, I think, will be to invest in a durable, low-maintenance infrastructure. If you constantly need to import replacements for broken parts you won't get off the ground; your margins for errors are too tight.\n\nYour energy sources are mostly limited to solar and wind, and solar is out for half the year, so you will have to be able to sustain yourself on only wind power; fortunately wind is plentiful in Antarctica (sometimes far too plentiful). Particularly strong and reliable winds circulate through the Southern Ocean, conveniently located on all sides of Antarctica; placing your power infrastructure there seems like a good long term plan. Don't know about the practicalities of long distance power transfer, but if your city is coastal, it shouldn't be so bad.\n\nWhile soil farming will probably not be viable, with advancements in hydroponics you may be able to grow a small range of crops with only water, light, air, and trace nutrients. Heat will come from electricity from the wind power; trace nutrients can be imported easily; and water and air are readily available. Light is plentiful half the year (I think I once calculated that the poles get more light in the summer than the equator does, even accounting for the inferior angle), so you'd only grow annual plants unless you want to be very ambitious and grow plants on artificial lighting.\n\nEconomy is troublesome; pretty much any mineral resources you could dig up in Antarctica are more easily gotten elsewhere, and it seems a shame to colonize the place and start digging it up. Hunting options are of course very limited. Exports are mostly limited to intangibles (electricity and knowledge) and crops, none of which seem viable. You could try to export fresh crops to the research stations located elsewhere in Antarctica; the station at the south pole does not get fresh food for 6 months of the year, and I imagine they'd pay handsomely for a few vegetables in July. However transportation within the continent is perilous in winter. Really the best bet is to minimize the need for any imports at all.",
"They require a lot of supplies from the outside, but there are two civilian settlements on Antarctica now:\n\n[Villa Las Estrellas](_URL_0_)\n\n[Esperanza Base](_URL_1_)",
"From a practical standpoint, you just need sustainable natural power sources. I would imagine a combination of solar and wind, and possibly a type of hydroelectric. With sufficient power, your buildings are heated, your greenhouses are powered, and you could sustain a decent population.\n\nThe real challenges (legal/sovereignty aside) are large-scale fresh water supply and waste disposal systems. I know this because I had family living in Frobisher Bay (the populated area of Baffin Island in the Canadian Arctic) for a few years. You would require a very well planned city design for effective underground water and waste services, which would be very expensive to build and maintain, and even more so to expand. Population control would be another issue altogether, fortunately (or unfortunately), the Canadian Arctic does not have that problem.\n\nIf you're interested in reading up on this, I found what appears to be a decent paper on the topic.\n\n_URL_0_",
"I'd say no - and not because of resource availability.\n\nIt's my understanding that the outposts in Antarctica have to be repositioned as the ice moves towards the ocean, and it's not by small amounts, either.",
"Physically? Most likely. Legally? [No.](_URL_0_)",
"I've been thinking about colonizing Antarctica for the past few years, so this post excites me.\n\nThe key, I think, will be to invest in a durable, low-maintenance infrastructure. If you constantly need to import replacements for broken parts you won't get off the ground; your margins for errors are too tight.\n\nYour energy sources are mostly limited to solar and wind, and solar is out for half the year, so you will have to be able to sustain yourself on only wind power; fortunately wind is plentiful in Antarctica (sometimes far too plentiful). Particularly strong and reliable winds circulate through the Southern Ocean, conveniently located on all sides of Antarctica; placing your power infrastructure there seems like a good long term plan. Don't know about the practicalities of long distance power transfer, but if your city is coastal, it shouldn't be so bad.\n\nWhile soil farming will probably not be viable, with advancements in hydroponics you may be able to grow a small range of crops with only water, light, air, and trace nutrients. Heat will come from electricity from the wind power; trace nutrients can be imported easily; and water and air are readily available. Light is plentiful half the year (I think I once calculated that the poles get more light in the summer than the equator does, even accounting for the inferior angle), so you'd only grow annual plants unless you want to be very ambitious and grow plants on artificial lighting.\n\nEconomy is troublesome; pretty much any mineral resources you could dig up in Antarctica are more easily gotten elsewhere, and it seems a shame to colonize the place and start digging it up. Hunting options are of course very limited. Exports are mostly limited to intangibles (electricity and knowledge) and crops, none of which seem viable. You could try to export fresh crops to the research stations located elsewhere in Antarctica; the station at the south pole does not get fresh food for 6 months of the year, and I imagine they'd pay handsomely for a few vegetables in July. However transportation within the continent is perilous in winter. Really the best bet is to minimize the need for any imports at all.",
"They require a lot of supplies from the outside, but there are two civilian settlements on Antarctica now:\n\n[Villa Las Estrellas](_URL_0_)\n\n[Esperanza Base](_URL_1_)"
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slwnq
|
Which creature increases in body size most since birth?
|
I'm wondering if you took the ratio from the mature adult form of an animal, and divided it by it's birth form what would have the highest ratio?
Is it something huge like the blue whale, or is it some form of insect that (relatively) grows massively? Is it approximately the same for all animals?
Thanks Ask Science.
|
askscience
|
http://www.reddit.com/r/askscience/comments/slwnq/which_creature_increases_in_body_size_most_since/
|
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"From what I know, in terms of length the largest growth % is likely the Lion's Mane Jellyfish, which starts off as a tiny clump of cells around one millimetre in length and eventually grows to be up to 37 metres long. This is a growth of around 3,700,000%, an change in order of magnitude of 10^4 .\n\nIn terms of mass, I have no idea.",
"Some species of tapeworm have to be up there near the top. I know adult tapeworms over 50 meters can exist in whale intestines, their eggs are under 50 micrometers. Also, some of the giant trees like Redwoods and Sequoias. ",
"All squid are born/hatched as nearly microscopically sized creatures and it they grow and mature at an astounding rate. Take the colossal quid for example: when it hatches it is only a few millimeters in length but within two years it will be fully grown. The largest recorded specimen (found by New Zealand) weighed almost 1100 lbs. and was 33 m long.\n\nI don't know if this qualifies the colossal squid as the animal which grows the most, but it certainly would make it one of the most rapid growers."
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oxtgl
|
quantum particles reacting to observation
|
So, when you observe a particle it reacts differently as if it is aware??? what implications could this have in our own day to day lives, if any?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/oxtgl/eli5_quantum_particles_reacting_to_observation/
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"Any explanation of quantum mechanics in ELI5 will be woefully lacking in information, but I'll do my best.\n\nSome things (well, all things, on a sub-atomic level) exist in a state of superposition - that is, they are doing / in more than 1 place at once. But when we observe it, it has to pick 1 place. Shit is funky on that level.\n\nThe biggest implication of this in daily lives I can think of, its quantum computing, which takes advantage of objects that can be more than 1 thing at a time. A traditional bit has 2 states, on or off. A quantum bit can be 70% on, and 30% off, or anything in between. ",
"I always thought it was helpful to compare them to cockroaches. In the dark, when you can't see them, they're doing one thing. Flip the lights on & they do something else.",
"[A good introduction to the concept](_URL_1_).\n\nParticles are not thought to be aware.\n\nParticles can exist in a state that is \"indeterminate,\" meaning that it cannot be predicted how they will act, no matter how good your predictions are. Observation of a particle means that you must interact with it in some way (e.g. shine a light at it), and this interaction makes the particle stop being indeterminate in the way it was before. There is no way to determine beforehand what option the particle will take when you shine a light on it, making it truly random. There are different theories about how this happens, but the fact remains the same.\n\nAn implication for day-to-day living might be a [true random number generation](_URL_0_) which cannot be achieved by traditional computing technology alone.",
"[There's a decent ELI5 on this topic from just the other day.](_URL_0_)",
"Here's the ELI5 version. Quantum particles are not reacting to observation- they are reacting to the interaction with other particles. In order to observe a particle, there must be a chain of interactions between that particle to another particle and so on, eventually all the way to you. The 'spooky' results of quantum mechanics which can be quite poorly phrased as a particle 'reacting to being observed' are much better phrased as depending on the chain of possible interactions between the particle and you.\n"
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65rjxg
|
how do "hive" applications get startup users? apps like tinder, meetup, and other social apps?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/65rjxg/eli5_how_do_hive_applications_get_startup_users/
|
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"Many don't start with a user base.\n\nQuite a few buy the information they will need to start from a similar business with a different focus. Think buying traffic flow data from Google maps or how many people in what areas are looking for hot singles near them from bing.\n\nAfter that they will advertise millions and millions of dollars in advertising, hots special prizes for joining earlier, have bots, and staff do the heavy lifting till the user base picks up. Just like forums really.",
"Not a direct answer to the question, but any service that requires a group of users to work relies on \"network effect\". That is, the value of the service is very dependent on having the right number of users in its network. Having too few people on a dating site makes it useless, or in business terms, it has little value. \n\nWhen starting such a service, the cost to acquire each user is an important cost to factor into business plans. ",
"Smaller companies lean heavily on word of mouth. Tell everyone you know and beg them to tell everyone they know. It was how I found out about the Her app back when it was datch I think it was called. ",
"One of the simplest methods is simply not to launch until you have X number of users pre-signed up, i.e.:\n\nWe are launching soon enter your email to be notified when we do\n\nThe peril there is your concept and marketing has to be strong enough to bring them back when you launch. You also need to be aware 1 email != 1 user\n\nThere are bots thy just fill in forms, users that don't bother returning, bounced and changed emails and so on. Rule of thumb tends to be around 10-30% usually come back to check it out",
"\nTinder targeted a few college campuses when they first launched in the fall of 2012. These colleges included \"party\" schools such as USC. 90% of users were ages between 18-24 in 2012. \n\nI would suspect other social/dating apps would begin in colleges as you have aggregated amount of young people in one area. ",
"As others have noted, many of them start off with a small, easy to target niche. Facebook and Tinder started off with colleges because college students have a shared identity that their marketers could leverage, it's easy to test your messaging when you can actually watch people react, and young people tend to be early adopters of new technologies.\n\nSome marketplace-type apps cannibalize their competitors. For instance, AirBnB started off putting listings on CraigsList pointing to their own platform, to get people to switch. I've also heard of companies selling things on eBay and including materials promoting their own apps. That way they're getting the best possible users, the ones who are already doing what they want them to do and just need a better way to do it. That minimizes the number of users they need to get in the door to get a useful amount of activity going through the product.\n\nSome companies use a honeypot approach, where they launch a product that doesn't depend on network effects, then use that to build up their audience enough to later switch on the parts that are dependent on network effects. OkCupid started out as just a bunch of wacky, fun questions that you could share with your friends. Then once they had some number of people, they rolled out the ability to find other people based on how close their answers are to yours.\n\nSome go for broke and just try to sprint past it. They build a product dependent on network effects, raise millions of dollars, and sink most of that money into marketing to almost immediately grow the userbase large enough for the product to be useful.",
"The heart of your question is really 'How are social networks formed?\" The textbook answer is that you need a **critical mass** of users, so that when someone new signs up, there are other people to interact with. Otherwise no matter how many people download your app, the newcomers will just leave if people are just trickling in, which means the app will be perpetually unpopular. The key then is to get a large number of users *at once*, so that the network becomes sustainable.\n\nHowever, this answer only leads to more questions because it creates a paradox that many people refer to as \"the chicken and the egg problem.\" How can you convince the first users to sign up when no one else is around? Unfortunately, there's no easy answer, which is why businesses are willing to pay an incredible amount of money just to buy an existing social network. If you've ever wondered why Instagram, Snapchat, and Twitter are worth so much even though they have no clear business model, this is exactly why (social networks are valuable because they are very difficult to create).\n\nNevertheless, here are a few guidelines that can help create a network. They don't always work (e.g. Google+ have tried and failed), but these are characteristics that successful social networks share:\n\n1) Start with a small but concentrated population. For example, Facebook was initially only available to Harvard students. Once it reached a critical mass of users there, it then expanded to other ivies, and then to all colleges, and finally to everyone. The same can be seen for dating apps like Coffee Meets Bagel, which first started off in NYC, and then gradually expanded to other cities before opening up to everyone. \n\nWhen you start off with a localized population, you lower your marketing costs and you get more mileage out of word of mouth. It's much easier to simultaneously sign up 1000 users in one city than it is to simultaneously sign up 1000 users in a thousand cities.\n\n\n2) Rely on users to recruit other users. Social apps become more useful when more people sign up, which means the users themselves are interested in helping advertise the app. For example, Venmo isn't very useful if your friends don't use it, so there's already an incentive for you to get your friends to install it. This growth will happen slowly over time, but because a critical mass requires a lot of simultaneous new users, you can speed up the process by rewarding existing users who help you expand your network. Venmo did this with a $20 referral bonus to both the new user and the friend who referred them. Other apps reward in-app currencies or features, such as letting you message more people on dating apps.\n\n3) Minimize sign up costs for users. If you've ever wondered why many computer games (e.g. League of Legends) and mobile games are free to play, it's because the very presence of a user is valuable. A multiplayer game would be unplayable if no one else is there. Thus, companies will literally pay new users (e.g. Venmo example above) to sign up. Of course, this is very costly, so the next best thing is to offer the app for free. ",
"At a high level, every new/innovative product (or service) introduced in a marketplace starts with the *Early Adopters*; these are people who are unhappy with the status quo, the stuff out there, and they are looking for something new that fits their needs/wants, often by *hacking* the present products.\n\nEngage then early adopter and ... that's just the beginning.\n\nFor more: _URL_0_",
"PayPal paid $10 to sign up for a while.\n\nSource: Notes on startups, or how to build the future by Peter Thiel",
"There's a locally developed app for music sharing, sharing information about shows and the scene, etc. I learned about them at a music conference, where they started to market and share the app with musicians in the area. They are currently on a tour across the country interviewing and recording musicians from all over the US. They're putting together some good video content and sharing it online.\n\nIt seems like it's a tough grind.\n\nActually, I just remembered something. They held a talk at my college and got Andrew W.K. to talk about the app before I learned about them at the music conference a couple of years later.",
"To add to the other answers here, you can also \"buy\" users, but not in the traditional sense. What I mean is you can reach out to internet celebrities that already have their own fan base, and ask them (pay them) to use your app and bring their followers with them. This may not work for dating sites, but it can work for user-generated content sites like blogs, video streaming, etc.",
"Some of these apps also started as a different platform entirely. When Instagram first started it was promoted as an image filter app but you were forced to create an account to use their filters. It happened to have a feature that would let you post on Facebook and twitter at the same time in exchange for posting on their social network. So it kind of built up that way. \n\nSnapchat was marketed as a private messaging app that happened to grow into its own social network. ",
"I was on Grindr when it first started. On the original iPhone. The nearest person was like 20-50 miles away. And littered with dick pics as profile pictures. The good old days. ",
"What a lot of people seem to neglect in their replies that critical mass isn't just down to the number of people using your service. But the number of people who use it in a particular area.\n\nThis makes universities an extremely good place to target your services. Facebook started out as a way for students to keep in touch that was better than myspace. Tinder likely the same.\n\nYou need to find a high density of the demographic you're targeting and market the fuck out of your product to them. (reddit stole fark users)",
"I work(ed) for a company that had this exactly, I can tell you the answer is money and speed.\n\nI can't give away too many details about the company without giving it away, but we were spending upwards of $25 per person to build an account. It's not that we were paying them, but we used feet on the streets, and face to face interactions with an army of hourly people to just get as many downloads as we possibly can. \n\nWe did this quickly. We just accepted that the first 100-1000 users were going to have a bad time, but once we artificially cranked the wheel enough, we could take our hands off of it and it would go on it's own, and that is exactly what happened. ",
"Social networks rely upon something called \"network effect\" to provide a benefit to the user.\n\n- You need a lot of users for the features in the application to work the way they are meant to\n\n---------\n\nExample: Using a dating app with only 10 users.\n\n- You log into the app and only see 10 people\n- You aren't likely to date any of those 10 people\n- You aren't likely to even connect with any of those 10 people because you don't match\n- None of the features like search, messaging, favoriting, etc provide any value because the isn't a network to interact with\n\nFor many applications the network needs to be in a specific vicinity for those features or the key benefit of the application to be obtained.\n\nExample: A dating app with 10,000 users but, the users are spread across the world with only 10 users in any given city.\n\nEven though you have many times more users you're still going to have the same shitty experience as if the entire application only had 10 users.\n\n------\n\nSo, what do applications that rely upon the network effect to provide a benefit and value to their user?\n\n- They can create many fake accounts to give the illusion of a big network which leads to actual users joining\n- They create alternative benefits for users that do not rely upon a network effect--like creating contests or giveaways in the application tied to using it, paying users to use the app, creating affiliate programs paying people to get their own network to join and use the app, specific features the aid in the experience (like personal matchmaking or dating consultation services), etc\n- They partner with a much larger network and offer incentives to the partner to on-board their users--like an affiliate program arrangement\n- They acquire an existing company with an establishing network\n\nIf the application's network effect does require the users of that network to be within a close proximity of one another the strategy is focused on a single specific area at a time.\n\nDating apps and ride sharing apps are great examples of this. They start in hyper local areas (college campus) and slowly extend outward. Once they capture a large % of the market in that area they roll out to a new area and build further.\n\nDefinitely read up on Tinder, Bumble, Uber, Lyft, DoorDash, Facebook, Snap, etc for interesting examples of how they each did it a little differently.\n\n------\n\nEverything distills down to an experience. \n\nA user judges their experience not just upon using the application but, upon every instance of interacting with your company--directly or indirectly through word or mouth/reviews.\n\nWhatever strategy is created and implemented usually supports the overall experiential goal that the social network represents...the key benefit of being a part of that network.\n\nIf you're trying to do this yourself, always be aware of this and always do what enhances the experience by having every strategy, decision, and action in alignment with each other and the overall goal.\n\nIf what you do does not support that goal, you're only creating confusion/discomfort for the user and taking away from that experience.",
"Op read up on customer acquisition funnels and strategy. Much of it is data mining your analytics, tweak it until you figure out where acquisition is less than the value of the customer and then start throwing money into that specific strategy. Having a really good analytics team can help you bring customers into your platform for cheap.",
"random sidenote but I had an idea for an app called \"MeetUp\" where you can find people near you who share your interests\n\nand then i found out that it already existed with that exact name lmao",
"Pretty sure I heard somewhere that Tinder started with a huge party. To get in, you had to download and use the app before you came (no pun intended)\n\nMost people left that party pretty happy. ",
"I was offered a promo job for some dating app a year or so ago. We walked down the line of club liv with 'cool' light up shit that drunk tourists live for. If they downloaded our app, they got a random prize and a voucher for a free drink if one of their friends signed up before they entered the club. (Drinks at liv are like 30$ so almost everyone did it) imagine them doing this in miami, la, new york, chicago etc on the same night in multiple clubs per city? The tourists go home, the app alerts them to nearby people and they start using it... they are in those cheezy club photos you take at the entrance with the glasses, boom sticks, pins, phone cases etc with the logo on it. Of course they post that super cool time they went to liv on their social media.... advertising to more people. It was pathetic to watch people give up personal info, effectively selling themselves to advertising companies, to get a fucking light up ring. ",
"It's less important to have a *lot* of users, and more important to have a big percentage of your users be able to connect with each other.\n\nIf facebook had a user-base of 50 people, and each one was from a different city, none of the users would find it all that useful of a platform. But if those 50 people were from the same school, they might find it to be useful. And those 50 people would start telling their friends that aren't on facebook to get on facebook. And everybody that signed up would have at least a few people that they could talk to, and they'd start telling their friends to get on facebook. You can see how quickly these numbers can skyrocket.\n\nYou only need a small starting point and a well designed platform for it to blow the fuck up. \n\nWith that said, there's also the option of buying users, or recruiting them from other social media platforms. You'll see people doing this a lot on reddit, but usually only in the smaller subreddits. Fake user accounts is another option.",
"Well, there's a few ways. You could look to how Reddit did it. Looking through the comments, surprised nobody saw it. Basically, they setup the site and then created a pile of alt accounts. As people would post, they'd patiently remind them of the rules and guide them into the behavior of the kind of user they wanted to attract. They also quite literally had conversations with themselves to give the appearance of a larger (and more cohesive) userbase than actually existed. It was basically a re-enactment of the monkey story -- and eventually it reached critical mass and started growing on its own and the alt accounts went defunct. The site you see today is the result of those early efforts. \n\nWas it dishonest? Maybe. But that's how a lot of sites kick off. Slashdot did the same thing, before it rose to prominence in the IT world... and then they sold out and it all came crashing down. There's actually many, many forum-based sites where when they initially went live, it was mostly the author/owners going to other forums and canvasing to draw people to their site and giving the appearance of more activity to keep people around until that critical mass point tipped over and it became self-sustaining.\n\nThere's also examples where they didn't do this and trusted that the mere brand identity or whatever would carry the day: Google+ for example, also known as the Ghost Town of the social networking world, or Hangouts, which is yet another attempt by Google to shove something down people's throats that totally isn't working out. I'm sorry to say, but if you're the only one at a party, more people showing up isn't gonna happen. You need that core glob of people to start roping others in, and even if you have to fake it, it's better than just kicking off the site and then promoting it without that (even fake) activity to engage people. \n",
"Hey! So I was actually recruited to help spread an app like Tinder because I'm a sort of influential member of my campus and in a fraternity. The one I \"worked\" for offered commission for certain thresholds of downloads for my area, and it was monitored via how many people stated they were at my campus. The app that was described to me versus the actual app in function was very different, and honestly pretty sleazy. The developer was my point of contact and would every couple weeks check in and tell me some new even shallower feature that they added.\n\nAt the end of it all, after I had given up trying to spread this app that I ultimately decided was not something I wanted to support, he sent me a very unprofessional email basically saying, \"Hey! You know how we said we would pay you? Turns out we can't!\"\n\nSo yeah. A lot of the apps rely on getting some college kids to whore out downloads from their friends.",
"This is actually a specific occupation now a days, called growth hacker. Despite the name, _URL_0_ has a lot of interesting business cases of how different businesses did it.",
"Some apps have a 'pre-order' like sign up phase where you create your account before the app actually comes out. That way, when the app launches, it could already have thousands of users, many of which are excited for it to come out and will start eagerly using it from day 1.",
"I found Tinders story pretty cool. From what I recall they actually threw a party at USC and had everyone there download the app and it grew at least partially naturally from those people. Pretty sure it was like a couple sororities and frats. Look it up. ",
"It usually starts with local marketing. I had an idea for an app, and just by taking surveys people wanted to use our app, and kept asking us about it even thought it wasn't economically safe to start that app. Another app has had a history of bulling people out of the market by offering their larger more experienced infrastructure to users.\n\nSo, to answer the question it starts relatively small, but function, unless its comes from an existing company then its the big fish eating the little fish. ",
"Lots of people who can't, are afraid or don't have enough free time to socialize IRL. Wait the word to spread, make sure your app doesn't suck and you're good to go.",
"All you guys are tip-toeing around the reality - they use bots, buy users are do all kinds of grey area stuff to get to the critical mass. Everyone does that.",
"Tinder went to colleges and sponsored parties at the college bar. Cover charge was free if you showed your phone had the app installed. ",
"Get young women to sign up.\n\nEvery successful social network has started by focusing on teen and college age girls. Tinder actually started by bribing sororities.\n\nGoogle+ gave out early access to 30-40 year old male tech bloggers. Guess what happened to them.",
"This is a huge part of what killed Google+. Google did a slower rollout of Google+ and throttled who was allowed to join. When interest was highest for Google+ only a small group of people were allowed to join. Those folks eventually got bored of talking to each other and didn't use Google+ as much. When Google+ was finally opened up for anyone to join all the early adopters already left due to boredom.\n\nThe slow-rollout approach worked fine for Gmail, because you can still email people on other services. Gmail for a long time was invitation-only, and getting invited was a very desirable thing.\n\nGoogle effectively killed any chance of success for Google+ by not releasing it for everyone at the same time.",
"Some of them used a bunch of fake user accounts manned by an ops team. I won't name names but I worked for a company that started like this.",
"For dating apps like Tinder the answer is obvious; seed the network with fake users so the first users don't see a ghost town, drop a load of money on marketing to get massive adoption quickly, then phase out the dummy accounts as the real users come in.\n\nIt's also common to do a phased regional roll out. Target the big cities and college campuses first which tend to set the trends for everyone else. Once some buzz is going in those areas then you expand your marketing to broader markets."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Crossing_the_Chasm"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"https://growthhackers.com/"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
||
bm0sig
|
How long after clinical death, can someone be revived?
|
How long without damage to the body (brain, heart, etc.)? And how long before being unable to keep yourself alive (breathing by yourself, without help)?
|
askscience
|
https://www.reddit.com/r/askscience/comments/bm0sig/how_long_after_clinical_death_can_someone_be/
|
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"It’s quite variable, but even with good CPR and return of spontaneous circulation after only a few minutes people can have quite significant hypoxic brain injuries. If you’ve been having CPR for more than 10-15 minutes your chances of survival are pretty slim.\n\nThere are certain cases where this doesn’t always hold true. Hypothermia is the classic one, because the low temperatures preserve the brain. It also depends on the quality of the CPR given. Also probably depends how healthy you are to start with.\n\nI have to say that if I’m doing CPR for longer than 20 minutes I’m thinking about stopping 95% of the time.\n\nThe caveat to this question is that actually the time of death is 5 minutes after the last heartbeat, so you’re not even officially dead for the first 5 minutes. And if you started CPR after 5 minutes of no cardiac output your survival chances are even lower. So the question is probably flawed.",
"There's the well known (in the UK) case of Fabrice Muamba\n\n* Premier League footballer. Exceptional fitness. \n* Witnessed cardiac arrest on-pitch during a match l. Ventricular fibrillation. \n* Almost immediate medical care provided by 5 immediately available qualified medical staff (doctors and paramedics)\n* Immediately accessible AED and oxygen were at the pitch side. \n* Consultant cardiologist in crowd made his way to pitch promptly to guide treatment, Dr Deaner. \n* Heart stopped for *78 minutes*. 15 defibrillation shocks in total prior to hospital arrival. \n* Consultant overrode initial hospital decision to redirect to his own specialist hospital, the London Chest Hospital - which had the necessary equipment for better care, despite being further away. \n* Specialist cardiologists and neurologists were on standby at London Chest Hospital, some had even been listening to the match on the radio and were aware of the situation\n* Treatment was provided immediately on arrival\n\nSo yes, an out of hospital witnessed arrest can still lead to ROSC after an hour. It helps if you have the fitness of an elite athlete, youth, immediate treatment, an onhand cardiologist and the medical resources and hospital of the capital city of a first world country. \n\n_URL_0_",
"bottom of the ocean, assuming your a little girl, record is 66 minutes. \ndeep sea diver survived 38 minutes 3°C. Still alive [_URL_0_](_URL_0_) \nThe lower the temperature, less oxygen brain needs.\n\nif DNA stops aging due to Cryopreservation, presumably **millennia** \n\n###"
]
}
|
[] |
[] |
[
[],
[
"https://www.theguardian.com/football/2012/mar/25/muamba-collapse-minute-by-minute"
],
[
"https://www.youtube.com/watch?v=jvRuKHeEvWM"
]
] |
|
13wjk0
|
A few questions on physics & particles
|
Hey all, I'm in 10th grade in NY so by state education law I'm required to take a Chemistry course this year. However, I'm much more interested in Physics, which is what I'll be taking next year. I've just been thinking about it and I've come across a few questions.
1.) Does light have a mass? because I've been told (so far) that it doesn't. But wouldn't that break e=mc^2, causing e to be 0? I thought light does have energy? and could e^2 = (mc^2 )^2 + (pc)^2 be displayed as a right triangle by Pythagorean Theorem?
2.) What is a photon?
3.) What is a negatron?
4.) Will I ever have to divide by 0 in a physics course? (Just this completely random, nonimportant question.)
Thanks!
|
askscience
|
http://www.reddit.com/r/askscience/comments/13wjk0/a_few_questions_on_physics_particles/
|
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"1) Light doesn't have mass but it does have momentum.\n\nI have seen it as a triangle actually so yes but it seemed pretty pointless to me\n\n2) A photon is a particle of light.\n\n3) Never heard of it.\n\n4) If you do, someone is doing something wrong.\n",
"E^2 = (mc^2 )^2 + (pc)^2 is closely related to the Pythagorean theorem, but not in the way that you'd think. In space, if I have two points, one at (0,0,0) and the other at (x,y,z) then the Pythagorean theorem tells us the distance s between the two points is\n\ns^2 = x^2 + y^2 + z^2\n\nYou may not have seen the 3D version (with z included) but it should make sense.\n\nLet's say I have a *vector*, or an arrow with a length and a direction. If the arrow has a starting point at the origin (0,0,0) and an ending point at (x,y,z) then the length of the arrow is given by the Pythagorean theorem above. We'll come back to this in a second.\n\nIn space*time*, we can define a \"spacetime distance\" between any two events, and we can use a spacetime Pythagorean theorem much like the old one, except it turns out (in order to be consistent with special relativity) that the time term has a minus sign in front of it (and a factor of c^2 to make the units work out, since time and space have different units):\n\ns^2 = -(ct)^2 + x^2 + y^2 + z^2\n\nIn physics we like to deal with *four-vectors*, which are like the vectors I talked about before, except these are arrows which point both somewhere in space and in time (for example, its time component may point two seconds into the future). So by the same logic above, if I have a vector with components (t,x,y,z), the spacetime Pythagorean theorem will give its length.\n\nEnergy, momentum, and mass are all related by a particular four-vector called the [*four-momentum*](_URL_0_). It's a sort of generalization of the momentum vector (which you'll see next year in your physics class) to special relativity. The relation is this: the time component of the four-momentum is energy (divided by c, again because of units), the spatial components are the momentum, and the *length* of this four-vector is -(mc)^2 (don't mind the minus sign, it's a technicality to do with the fact that particles have to travel less than the speed of light). So using the spacetime Pythagorean theorem we can see that the relation between these three is\n\n-(E/c)^2 + p^2 = -(mc)^2\n\nwhich, if we multiply both sides by c^2 , gives us\n\n-E^2 + (pc)^2 = -(mc^2 )^2\n\nor\n\nE^2 = (mc^2 )^2 + (pc)^2"
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Four-momentum"
]
] |
|
23hzaj
|
Were gestures such a big part of conversation in ancient Rome as they are in modern day Italy?
|
The Italians are famous for their non-verbal expressiveness, while most pop-culture depictions of Romans have them be very reserved in their gestures. Which is closer to the truth?
Also if the Romans didn't gesticulate as much as Italians do, when did the change take place?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/23hzaj/were_gestures_such_a_big_part_of_conversation_in/
|
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"Yes, the Romans made extensive use of gesticulation in their speech, at least in their oratory and it seems in the streets as well. Cicero mentions them at some length in *De Oratore* and we have quite a lot of depictions of speakers in the process of motioning with their hands. Gesticulation in Latin and Greek was probably somewhat different, however. Latin was somewhat slower than modern Italian (although Vulgar Latin was probably still pretty rapid) and compared to Modern Greek Ancient Greek must have been frustratingly sluggish. Gesticulation seems therefore to have mainly been a method of conveying tone and emotion, as well as emphasizing certain points. We don't really know how much gesticulation was used in Vulgar Latin, nor do we know whether it would be used during a poetic recitation (probably not), but elsewhere it seems quite common. Most depictions of great statesmen from the Hellenistic Period on show them with an arm raised or something like that, which is a method of graphically representing the gesticulations that accompanied a good orator's speech. It's generally thought that when Antony murdered Cicero and ordered his head and hands cut off he did so because the hands were as much a part of the orator's toolkit as the tongue (also probably because Cicero wrote so much). A lot of our evidence for gesticulation is rather indirect, however, and particularly with rhetorical Latin it's important to remember that this is not what people actually spoke, even when proper speech was necessary. Rhetorical Latin called for extreme propriety of speech and grammar and played extensively on emotion, often by using metrical devices like in poetry (hence the phrase \"metric prose\"). But, for example, we find in Aristophanes that many gags point out characters' hand motions. Although Attic drama was very formalized and relied extensively on gestures to convey meaning (partly because it was difficult to do so with masks in the way, and partly because it descended from ritual dances and dithyrambs) it seems quite likely that such motions were used often. It's an interesting field of study, figuring out where gestures belong in plays and speeches. There's usually some sort of indication in the wording of a speech that there's supposed to be a gesture there. A pause in the meter, or a break in flow usually indicates that there's some kind of pause for effect, coupled with hand motions (for example, Cicero's \"O tempora! O mores!\" is quite obviously supposed to be coupled with an expression of woe, seeing as that it suddenly interjects into the middle of a thought with a formulaic expression of grief) and phrases that are supposed to be emphasized seem to have been accompanied by some hand motion to make the emphasis clear. Remember that Greek doesn't seem to have had a stress accent and literary and rhetorical Latin subverted Latin's already weak stress, since it was bad form. Oratory furthermore rarely used the conventional methods of showing stress, such as stating the personal pronoun even though Latin verbs don't need one, since those usually involved unnecessary repetition that was time-consuming (remember these speeches had a time limit) and poor rhetorical technique."
]
}
|
[] |
[] |
[
[]
] |
|
6z5zqd
|
why aren't tunnels under rivers straight?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6z5zqd/why_arent_tunnels_under_rivers_straight/
|
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],
"text": [
"The earth is not consistently made up of the same thing.\n\nSome areas are made of soft rocks that aren't very stable\n\nOther areas are made of hard rocks that are incredibly hard to drill through.\n\nIt's cheaper, easier and safer to curve your tunnel around these obstacles than it is to just drill a straight line. "
]
}
|
[] |
[] |
[
[]
] |
||
6ccv5g
|
Akin to electric field, does gravitational field store energy too?
|
askscience
|
https://www.reddit.com/r/askscience/comments/6ccv5g/akin_to_electric_field_does_gravitational_field/
|
{
"a_id": [
"dhtqmep"
],
"score": [
7
],
"text": [
"Yes. There is stored in gravitational potential energy, which is why, for example, things pick up speed when they roll down hill, as they are trading gravitational potential energy for kinetic energy."
]
}
|
[] |
[] |
[
[]
] |
||
5g4zs6
|
how does vinegar help hold a poaching egg together?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5g4zs6/eli5_how_does_vinegar_help_hold_a_poaching_egg/
|
{
"a_id": [
"daq3vpx"
],
"score": [
2
],
"text": [
"Vinegar denatures (unravels) the protein albumin that comprises much of the egg white. When albumin denatures, it unravels into a long strand of amino acids that form bonds with other strands of albumin. This phenomenon is called cross linking, and it results in the formation of a white milky skin on the other surface of the egg - which forms a sac that helps keep the rest of the egg compact instead of dissolving and spreading out in the water. The heat of the water, then cooks the sac-contained egg, resulting in a nice compact poached egg.\n\n"
]
}
|
[] |
[] |
[
[]
] |
||
9fy66f
|
how is powdered milk created?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9fy66f/eli5_how_is_powdered_milk_created/
|
{
"a_id": [
"e603mv0"
],
"score": [
3
],
"text": [
"The water content of milk is evaporated away until a hard substance remains that is ground into powder\n\nfrom wikipedia:\n\nIn modern times, powdered milk is usually made by spray drying[6] nonfat skimmed milk, whole milk, buttermilk or whey. Pasteurized milk is first concentrated in an evaporator to approximately 50 percent milk solids. The resulting concentrated milk is then sprayed into a heated chamber where the water almost instantly evaporates, leaving fine particles of powdered milk solids.\n\nAlternatively, the milk can be dried by drum drying. Milk is applied as a thin film to the surface of a heated drum, and the dried milk solids are then scraped off. However, powdered milk made this way tends to have a cooked flavour, due to caramelization caused by greater heat exposure.\n\nAnother process is freeze drying, which preserves many nutrients in milk, compared to drum drying.[citation needed]\n\nThe drying method and the heat treatment of the milk as it is processed alters the properties of the milk powder, such as its solubility in cold water, its flavour, and its bulk density. "
]
}
|
[] |
[] |
[
[]
] |
||
pmprm
|
X post from r/Atheism. Somebody explain how this is proof of evolution.
|
_URL_0_
There is the link. To the picture.
BTW: Im an Atheist.
|
askscience
|
http://www.reddit.com/r/askscience/comments/pmprm/x_post_from_ratheism_somebody_explain_how_this_is/
|
{
"a_id": [
"c3ql77w",
"c3ql7zq",
"c3qlcr0"
],
"score": [
14,
7,
30
],
"text": [
"First of all, on this subreddit please do not post things starting off with \"I am an atheist\". It isn't helpful to the subreddit at all to start a theism vs atheism arguement.\n\nThis particular diagram shows one of the best examples of evolution. Monkeys and other primates have one more chromosome than us. For years, people wondered where that chromosome had gone, for if we had evolved from them, we should have the same number, right?\n\nAt the ends of chromosomes are structures called telomeres, and in the middle, centromeres. These structures have unique genetic material that can be used to ID them. \n\nThis diagram is essentially showing that two of the more primal chromosomes (still possessed by chimpanzees) had fused in our case to form Human chromosome #2. Evidence of this is given by the prescence of telomeric sequences located in the middle of our chromosome #2 (when telomeric sequences should only be on the ends).\n\n",
"It is not \"proof\" in any sense, but it is very strong evidence. Broadly speaking: it shows that a single human chromosome is almost identical to a pair of shorter chromosomes from a chimpanzee spliced together. This implies that the two short chromosomes merged into a single longer chromosome during the evolutionary process. Some of our other panelists can no doubt provide a more detailed explanation, if you desire. \n\nMy fellow ask science panelists have caught me playing fast and loose with the term \"proof\" on several occasions, and I was certainly in the wrong. We need to be very careful differentiating \"proof\" from \"evidence\". The have very separate meanings, and we must restrain our intuition, which often seeks to conflate them.",
"What we are looking at here is a human chromosome (# 2) and two chimp chromosomes (2p and 2q). The dark lines and bands represent gene segments. As you can see they overlap between the two species. this is because chimpanzees and humans share a common ancestor. \n\nMore specifically about these two chromosomes (2p and 2q) it is understood that in humans we also had two #2 chromosomes, but after our split with chimps our two #2 chromosomes fused. \n\n[\"Humans have 23 pairs of chromosomes and other great apes have 24 pairs of chromosomes. In the human evolutionary lineage, two ancestral ape chromosomes fused at their telomeres producing human chromosome 2.[1] There are nine other major chromosomal differences between chimpanzees and humans: chromosome segment inversions on human chromosomes 1, 4, 5, 9, 12, 15, 16, 17, and 18\" ](_URL_0_)\n\n*More about DNA and determining common ancestors*\n\nBefore we had the tools to used DNA, we had to use similarities and differences between how species looked on the inside (skeleton) and outside (physical appearance) to determine how species were related. Darwin's great idea was that all life, all species share a common ancestor. This is referred to as descent with modification. Species that look more alike and share more traits are more closely related. Species that look less alike share less traits are more distantly related.\n\nFor instance we share a lot of traits with our fellow primates: nails, fur, our skeleton, forward facing eyes, grasping hands....We share less traits with say with a trout... they can breath underwater, we cannot, they have scales we do not... And trout share more common traits with other fish (fish have scales, fish can breath underwater). We share more common traits with primates then trout, so we are more closely related to primates then trout. And trout share more common traits with other fish so they are more closely related to fish then the primates.\n\nNow when DNA technology came along we found we could compare DNA sequences between animals and look for similarities and differences and see how closely or distantly species were related to one another. In some ways this is more reliable (but more complicated) then looking and physical and morphological features. I won't go into that here, but if you want to know more let me know.\n\nIn your picture it shows that many regions of the DNA sequence (black and white bands) overlap between chimps and humans. This is because we are very closely related, we share a not too distant common ancestor some 6 million years ago. After this time our respective DNA sequences have accumulated some differences, but not so many. If we were to put a rats #2 chromosome beside ours and a chimps we would see many more the bands not aligning. This is because we are more distantly related to rats then chimps. More changes have accumulated. So this gives evidence for evolution through the similarities of common descent. \n\nTL;DR this picture explains two concepts\n\n1. That the DNA between chimps and humans is very similar but not exactly the same\n\n2. That the #2 chromosome in humans is a fused chromosome (fused after our split with our last common ancestor with chimps), which remained separate in chimps (#2q and 2p)\n\n*edit* in science we don't prove something, we lend support to a proposed idea (hypothesis) if this hypothesis gains a lot of support (through repeated testing by independent scientists and through physical or observable evidence), and there is no evidence to refute it then this hypothesis becomes a theory. A theory (like the theory of evolution) is backed up by a lot of evidence, and for over 100 years (and even before it was known as a theory) scientists have yet to find evidence of any contrary processes working that cannot fit into the framework of the theory in one respect or another. Thus evolution stands as our best explanation for how species come into existence, change and evolve. No other proposed hypothesis to explain how species change have had any support or evidence. And evolution does not explain how life came into existence, those are other hypotheses."
]
}
|
[] |
[
"http://i.imgur.com/WVVEo.jpg"
] |
[
[],
[],
[
"http://en.wikipedia.org/wiki/Chimpanzee_genome_project"
]
] |
|
5ma5kw
|
when a jar won't open, why does hitting it from the bottom, or tapping the lid on the edge of the counter, work to make it easier to open?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5ma5kw/eli5when_a_jar_wont_open_why_does_hitting_it_from/
|
{
"a_id": [
"dc20429",
"dc278q8",
"dc28iqr",
"dc2juhz",
"dc2k7a0"
],
"score": [
8,
8,
2,
2,
2
],
"text": [
"A jar won't open is often due to pressure. Hitting a jar from the bottom rarely works for me. What I do is put it under running hot tap water for 30 s and it usually opens. When it's heated up, pressure in the jar changes. Someone please correct me if I am wrong ",
"Tapping or tampering with the lid loosens the seal, allowing the pressure to equalise slightly. This makes it easier to remove the lid.\n\nI have personally found it most effective to tap firmly with a spoon all around the top edge of the lid. This creates slight deformations in the lid, weakening the seal fairly substantially.\n\nJars are pressure sealed. This is actually usually a byproduct of the production process - the jars are filled hot and then cooled. When the contents cool, they contract (all materials, with few exceptions, shrink in volume/size as they cool). This creates a partial vacuum inside the jar, an area of much lower pressure. As a result, the higher pressure outside the jar forces the lid on tightly. You can do this yourself if you get some jars and make your own jam or other preserve. They're prepared hot, then poured into jars and left to cool.",
"The only thing I know that works is hitting the lid of the jar to deform it (with like a butter knife). The deformations make it easier to turn the lid. ",
"Most jars like you are talking about are packaged while heated. As the contents cool down a vacuum forms in the container which makes it harder to unscrew the lid. \n\nSmacking the bottom of a full jar can cause gasses trapped in the contents of the jar to be released (just like shaking a can of sofa). This increases the pressure inside the container making the lid a little easier to remove. \n\nFinally, don't underestimate the power of a good smack on a sealed container. The shock forces you generate can slightly deform the lid making it easier to open. \n\nDO NOT TRY AT HOME:\n\nFun fact. If you take a sealed, full glass bottle of Snapple and smack it firmly with your hand on the lid (the way you might smack the bottom of a pickle jar to open it) you can generate enough force to cause the bottom of the Snapple bottle to completely sheer off.\n",
"The most effective method is to use the curve of a spoon as a lever against the side of the jar to lift the bottom edge of the lid just enough to allow air in and break the vacuum that seals the jar tight. It may take experimenting with different sized spoons to get the right angle and grip on any specific jar and lid combination. Some jars need that small pointy spoon to get under the lid because the fit of the lid on the jar has so little space to access it. If too little space is available to get the spoon under the lid, try a butter knife levered over some fulcrum for the knife to rest on."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
||
2i569p
|
Why Does Drag Begin To Reduce After An Object Breaks The Sound Barrier?
|
I was watching [Balakrishnan's classical physics lectures](_URL_0_), and he mentions that the drag force in air begins linearly, then becomes non-linear, and then starts to quickly drop off after the sound barrier is broken. I couldn't get an intuitive understanding for why this is. Also, what happens to the drag force as you continue to go further and further past the sound barrier? Does it level off and then continue rising again?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2i569p/why_does_drag_begin_to_reduce_after_an_object/
|
{
"a_id": [
"ckz29q8"
],
"score": [
14
],
"text": [
"It depends on the aircraft. The decrease seen in the lecture isn't universal to all objects, here's a [swept-wing](_URL_0_) drag profile: \n_URL_3_ \nAnd here's a [straight-wing](_URL_5_) drag profile: \n_URL_4_ \n\nBesides geometry, you have to consider that the same sources of drag for subsonic aircraft aren't the same as for supersonic aircraft: \n_URL_1_ \n_URL_7_ \nDifferent sources of drag contribute and dominate different in different speed regions. For instance, skin becomes less dominant because at higher speeds, the air near the skin becomes more turbulent. This turbulence actually lowers the drag as turbulence causes local low pressure regions: \n_URL_2_\n\nThis stuff is *very* complex. Turbulence despite what anyone tells you is not easily understood. We only ever consider the \"broad strokes\" of how it works, but once you even get rudimentary complex systems, everyone switches over to empirical and experimentally determined mathematics because the analytical solutions are just too difficult or unwieldy.\n\nTwo other factors become really important. The first is drag due to lift becomes less important. Due to the nature of supersonic shockwaves, wings can't generate lift as effectively in supersonic speeds. Swept-wing aircraft are better able to generate lift at high speeds, thought it directly corresponds to more lift-drag. The other factor that becomes important is wave-drag. This is the drag of the shockwave and it becomes the dominant form of drag for supersonic aircraft and results from the compressibility of air. Here's some other resources on drag: \n_URL_6_ \n_URL_8_ \n"
]
}
|
[] |
[
"http://www.youtube.com/watch?v=ucG_Ft36XOo&t=16m15s"
] |
[
[
"http://en.wikipedia.org/wiki/Swept_wing",
"http://scilib.narod.ru/Avia/DAC/images/fig014.gif",
"http://upload.wikimedia.org/wikipedia/commons/c/c6/Drag_sphere_nasa.svg",
"http://scilib.narod.ru/Avia/DAC/images/fig035.gif",
"http://scilib.narod.ru/Avia/DAC/images/fig036.gif",
"http://en.wikipedia.org/wiki/Lockheed_P-80_Shooting_Star",
"http://homepages.wmich.edu/~y3yang/files/handouts/chap14082.pdf",
"http://soliton.ae.gatech.edu/labs/windtunl/classes/hispd/hispd03/sources_of_drag.html",
"http://scilib.narod.ru/Avia/DAC/dac.htm"
]
] |
|
5mw2p9
|
If atmosphere moves with the earth, how does every part of the atmosphere move at the different speed required for it to stay in place?
|
[deleted]
|
askscience
|
https://www.reddit.com/r/askscience/comments/5mw2p9/if_atmosphere_moves_with_the_earth_how_does_every/
|
{
"a_id": [
"dc7oeab",
"dc80twu"
],
"score": [
5,
2
],
"text": [
"Short answer, they don't. Air moving along a rotating surface into an area where its previous velocity is inconsistent with its new location generates coriolis effects. Among other things, these cause hurricanes, and is why they always spin counter clockwise in the northern hemisphere and clockwise down south.",
"The other comment is about the horizontal component of the coriolis force. You asked about the vertical part. It is called the [Eötvös Effect](_URL_0_). Objects moving up or downwards are deflected into east or westward direction respectively. "
]
}
|
[] |
[] |
[
[],
[
"https://en.wikipedia.org/wiki/Coriolis_force#E.C3.B6tv.C3.B6s_effect"
]
] |
|
1lakjm
|
why do we order steak on a "rare- well-done" scale and not chicken?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1lakjm/eli5_why_do_we_order_steak_on_a_rare_welldone/
|
{
"a_id": [
"cbxazkj",
"cbxdz8h"
],
"score": [
18,
2
],
"text": [
"Because beef is a very dense meat, poultry is not. Since beef is very dense, it's rare for bacteria or viruses to live on the inside of the meat, generally they only live on the surface. That's why you usually sear the outside of a steak to kill any bacteria that may live there. \n\nSince poultry (and pork) are less dense, it's possible for bacteria to actually live inside the meat itself, hence why it's necessary to cook poultry to a certain interior temperature before it's considered safe for consumption.\n\nThis is also why you hypothetically cook hamburgers more than you cook steak. Since the inside and outside of ground beef get all mixed up, there may now be bacteria inside of the ground beef.",
"The real reason is because of storage. I've eaten \"rare\" chicken before (Japanese cuisine) and it was actually pretty tasty. But as it turns out, these places have their chicken so fresh they are still rigid from rigor mortis. Getting chicken this fresh enough for the average individual would be insane. \n\n_URL_0_\n\nThe way mass produced meat is handled, the entire thing is just a big fight against time to prevent pathogens from building up on the meat. Poultry is harder to handle for mass operations so its basically just a no-go to get them fresh enough to not be eaten at anything other than well-done. "
]
}
|
[] |
[] |
[
[],
[
"http://www.thedailybeast.com/newsweek/2013/07/17/chicken-sashimi-is-the-other-pink-meat.html"
]
] |
||
50laan
|
How quickly can the human body gain weight?
|
Could someone consume enough calories and turn that energy into fat quickly enough to Pop? (to some degree or another)
|
askscience
|
https://www.reddit.com/r/askscience/comments/50laan/how_quickly_can_the_human_body_gain_weight/
|
{
"a_id": [
"d76fs3s"
],
"score": [
5
],
"text": [
"In extreme cases, [MMA fighters can dehydrate themselves enough to lose 30 pounds in 5 days](_URL_0_), and then gain 30 pounds in 24 hours by rehydrating. However, this is both medically dangerous and unsustainable for a longer period."
]
}
|
[] |
[] |
[
[
"http://fourhourworkweek.com/2013/05/06/how-to-cut-weight-ufc/"
]
] |
|
29hegc
|
Did Hitler ever find out that Himmler and Heydrich falsified the reasons for the Night of the Long Knives?
|
Himmler and Heydrich destroyed Rohm for personal and aspirational reasons- did Hitler ever come to understand that he'd been played a bit? Did he retaliate in any way or did the resulting power that the demonstration and purge provided negate any hard feelings?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/29hegc/did_hitler_ever_find_out_that_himmler_and/
|
{
"a_id": [
"cil0v1n"
],
"score": [
8
],
"text": [
"The Röhm-Putsch got rid of a whole array of competitors to Hitler. We have no reason to believe this was not in Hitler's best interests. The SA by the time was seen by the public as a too-brutal movement, and Hitler was able to polish his image by pretending to clean up the \"crooks\" among the Nazis. In other incidents, Hitler played those under him against each other, allowing their career motivations to have them fight it out, stabilizing his position no matter the outcome."
]
}
|
[] |
[] |
[
[]
] |
|
1sfakg
|
why are passwords with extra characters like numbers and symbols considered "stronger," as opposed to just a password that's longer.
|
So lots of sites now ask for passwords that have at least 1 number and/or at least one symbol. What I don't understand is how this makes the password stronger.
I mean, of course, I understand that with > 26 characters, the number of possible password combinations increases significantly, but if the "cracker" trying to decrypt a password doesn't know if you have all letters, or a mix, they have to try them all anyways, don't they?
So it would seem that the only thing that would make a password stronger would be increasing the length of the password. For instance, if my password is 40 character "a"'s in a row -- if someone was trying to crack it, they'd have to go through every permutation of letter/number/symbol combinations for 1 letter, 2 letter, 3 letter, etc... until they get to 40 characters.
Alternatively, if my password is 8 characters long, and has a distribution of all the possible letter/symbol combinations, it's still cracked by the time the hacker gets to 8 letter passwords, hence much weaker, right?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1sfakg/eli5_why_are_passwords_with_extra_characters_like/
|
{
"a_id": [
"cdx1qed"
],
"score": [
2
],
"text": [
"Basically passwords on a server are transformed into a \"hash\" string that cannot be reversed back to the original password. When you login to a site, you submit your password and they run the hash function on it to see if it matches the stored value - if it does, you win. Now suppose a hacker downloads the whole password database somehow. He doesn't have your password, but he does have your hash (plus salt, but let's keep it simple). He can start generating strings and checking each one to see if its hash matches yours, and if so, that is a valid password (even if it isn't the actual PW you use!)\n\nYou already understand the concept of brute-forcing, i.e. try all combinations. So it seems that of course length is all that matters. The question is, where do attackers start? Do they just start enumerating a,b,c,...aa,...ab...,aba...? This would be really, REALLY slow. Instead they generate strings based on entropy, with more-likely strings coming first and dictionary words almost surely cracked in an instant. So adding numbers and symbols puts you WAY behind all that easy stuff, and makes it take a lot longer to crack your password. Even if the attacker knows he only has to make strings matching the symbol requirements, it'd still take a lot longer than if you just used alphabet characters. For instance, checking all 8-character strings with:\n\n(approximate since stuff like \"$$$$$$$$\" is ONLY symbols and wouldn't be a valid PW)\n\nAlphabet characters: 52^8 = 5.3459729e+13\n\nAlphanumeric: 62^8 = 2.1834011e+14\n\nThat plus symbols: 94^8 = 6.0956894e+15\n\nIt's hard to know exactly how many strings a hacker can check per second though, so look at it this way: if it would take him 5 minutes to check all alphabet-only passwords, it would take 20 minutes for alphanumerics and a little under 10 hours for the third category. Instead of getting a few hundred passwords in a day, he gets 2.\n\nThat said, longer is better when it comes to entropy - however, once you get to really secure lengths you end up with users easily forgetting the password unless they used dictionary terms. Sites choose password standards that balance security with user convenience, and usually build extra security so that your accounts are secure even if the password's stolen."
]
}
|
[] |
[] |
[
[]
] |
|
8g57j0
|
In equilibrium, why don’t pure solids and liquids affect the K value?
|
askscience
|
https://www.reddit.com/r/askscience/comments/8g57j0/in_equilibrium_why_dont_pure_solids_and_liquids/
|
{
"a_id": [
"dyavtti"
],
"score": [
4
],
"text": [
"Because the concentration of the pure substance (say concentration of H2O in water) does not change significantly in the reaction and therefore it cancels out.\n\nFor instance say you have C(s) + O2(g) < - > CO2(g). \n\nK will depend on the concentrations (= partial pressures) of O2 and CO2 but not the solid carbon. The pressure is lower on the right side of the reaction arrow, which should make the solid carbon expand somewhat (and thus have a lower density), so in principle it could be taken into account in this equilibrium. But in practice that effect is tiny; liquids and solids are not very compressible. That's the situation with how gases are interacting with liquids and solids.\n\nNow with aqueous species and liquids it's not always as simple, consider for instance the acid-base reaction: HA + H2O < - > H3O^+ + A^- \n\nWhich has Ka = [H3O+][A-]/[HA][H2O]\n\nIf you have a dilute solution, which is often the case, you can safely consider H2O to be a 'pure liquid' and set it to 1. But this is clearly a sliding scale; the more concentrated the solution is, the less valid that will be because you can no longer neglect changes in its concentration caused by the equilibrium. But that's why you have the 'pure' condition.\n\n\n"
]
}
|
[] |
[] |
[
[]
] |
||
9eq1kr
|
What medieval qualities did Europe still possess in its 15th and 16th century?
|
[deleted]
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/9eq1kr/what_medieval_qualities_did_europe_still_possess/
|
{
"a_id": [
"e5ru4t0"
],
"score": [
4
],
"text": [
"Well, I'm a medievalist and my specialty is the fifteenth century, so...hopefully, quite a lot? Hahaha.\n\nMore seriously, though--there are a few things going on here: the myth of medieval stasis, the difficulties of historical periodization in general, and the specific problems of \"the Renaissance.\"\n\nOne of the problems in thinking about a historical era with any kind of modern pop culture presence is the difference between \"accuracy\" and \"authenticity.\" That is to say, what *feels right* to us is based on the accumulation of modern interpretations of medieval/medieval-seeming things--LOTR, Game of Thrones, Kingdom Come, Sword in the Stone, \"once upon a time,\" children's Halloween costumes, and so forth. This impression will have some similarities to the past, but it won't be identical--it will reflect our modern concerns, what we want/need out of the past, instead of how it actually was. Hence \"authentic\" in feeling, but not necessarily \"accurate\" in fact.\n\nFor a span of time like the Middle Ages--a thousand years! An interconnected world occupying part of three continents!--one of the major distorting results of the preference for authenticity is \"medieval stasis.\" That is, we have an idea of ONE Middle Ages, one type of Middle Ages, with knights and castles and princesses and a belief in dragons. But in addition to not actually reflecting any one moment in the real Middle Ages, this monolithic \"authentic\" view is frozen in (fictional, or \"pseudo\" if you want to be Richard Slotkina about it) time. It doesn't capture the fact that the world changed *radically* between 500 and 1500--all the while still being \"middle age\" in the sense of occurring between the Roman Empire and what a handful of Italian elite men flattered themselves as being an intellectual revival of Roman ideals. And the world entered that time period changing, and continued to change afterwards.\n\nAnd not just change in a vacuum, but grow on its earlier self. That's why it's hard to draw a firm line between medieval and early modern (we'll get to \"Renaissance\"/rebirth in a moment). A lot of the things that we'd call \"early modern\" are medieval or late medieval in origin. Like, we'd say urbanization and the prominence of cities are very early modern--but this is a process that began in the eleventh or twelfth century in Europe; earlier (or never stopped) in the Near East. The Low Countries (Netherlands & c) are superstars of the early modern global economy--a position that began in the high Middle Ages. European imperialism expanded European political and religious domination far beyond a western European hub--a process occurring from the 15th century, the 12th, the 10th, the 6th depending on your point of view.\n\nNow, all those things are probably not what you mean when you say \"medieval\"! That's the authenticity versus accuracy problem, because they are all very definitely happening in the Middle Ages. So let's consider--Neuschwanstein, the prototypical medieval \"fairy castle,\" was built in the 19th century. Even Versailles is 17th. Soldiers were fighting with swords on horseback in World War I! Even after the invention of the printing press, handwritten notes and documents continued in dominance in a lot of cases probably until the rise of the affordable PC and (especially) cell phones. Universal literacy even in western Europe wasn't achieved until the 19th century.\n\nObviously, a lot also changed in that time. The point is--it's impossible to draw a single clear distinction between \"medieval\" and \"early modern\" and then point to elements of each that sneak into the other. That's both the problem and benefit of authenticity. It allows us an easy shorthand for understanding that the world did indeed change over time, but it's too easy.\n\nThe \"Renaissance\" muddles the picture even further. Once upon a time, \"Renaissance and Reformation\" was shorthand for the period of time after the Middle Ages. \"Early modern\" is a much more recent invention as a term. Part of the reason it has gained prominence is that scholars recognize just how limited the \"Renaissance\" was in its reach. We're really talking about a handful of elite Italians first, some Germans, and eventually French, English, some Spanish & c, mostly men but a few women, and wildly upper-class, urban people involved in an academic, artistic, and architectural movement focused on a particular type of revival of Roman tradition. (Of course, the twelfth century and the ninth century had experience their own versions of a Greco-Roman rebirth!) *Eventually*, yes, the same impulses that drove the Renaissance would swell up among other segments of the population, which is a big part of why today it seems like the Renaissance is so much the roots of the modern world. But as far as the early tinges of it go, it seems surprisingly isolated. \n\nIn fact, you could even go so far as to point out that if the Renaissance artistic and intellectual movement grew out of the late fourteenth, fifteenth, and sixteenth centuries, it itself *is medieval*.\n\nI know this isn't a neat list of middle-school-style textbook \"vocabulary word\" entries delineating what is medieval that still existed in 1600. Unfortunately, it's only pop culture that plays by those rules. History is a mishmash of \"change and continuity,\" and periodization is one of the messiest (but necessary?) results of trying to deal with that."
]
}
|
[] |
[] |
[
[]
] |
|
4hrnck
|
how is it possible that certain theories in math (euclid's 5th postulate, the comparability theorm) have been proven to be unprovable?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4hrnck/eli5_how_is_it_possible_that_certain_theories_in/
|
{
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"d2rs2df",
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2,
2
],
"text": [
"The easiest way to show that something is unprovable is to show that it is false. We did this with Euclid's 5th postulate (in a manner of speaking). There exist different types of space where it doesn't hold.\n\nI haven't heard about the Comparability Theorem, so I can't comment on how they showed it's unprovable.",
"A lot of this goes to [Godel's incompleteness theorems](_URL_1_). In a nutshell, he was able to show that in any rigorous system of logic that was sufficiently developed that it contained the rules of arithmetic, there will statements that are true within that system, yet are impossible to demonstrate they are true.\n\nOne interesting place this turns up is with the [continuum hypothesis](_URL_0_). In 1940, Godel (the same dude I mentioned in the previous paragraph) showed that the continuum hypothesis couldn't be false. Great, that means it is true, right? Everyone thought so, and everyone was happy, because this had been an open question for over 50 years, and lots of mathematicians cared about it. But, about 20 years later, someone else came along and showed that the continuum hypothesis also couldn't be true. Well now. A statement that can't be false, *and* can't be true. Is this a joke? The only conclusion: it is not true, and it is not false. In other words, it is independent of the other axioms upon which ZFC (the current logical framework for mathematics) is based."
]
}
|
[] |
[] |
[
[],
[
"https://en.wikipedia.org/wiki/Continuum_hypothesis",
"https://en.wikipedia.org/wiki/Gödel%27s_incompleteness_theorems"
]
] |
||
6f8rp9
|
if bacteria randomly mutate anyway, why does over prescribing antibiotics really matter?
|
I guess what I am asking is - tomorrow, a bacteria strain could randomly mutate to be resistant not only to current antibiotics but the random mutation could by chance make them resistant to what we happen to be working on next. Since mutation is just chance to a degree, shouldn't we just enjoy antibiotics all we want until the mutation occurs?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6f8rp9/eli5if_bacteria_randomly_mutate_anyway_why_does/
|
{
"a_id": [
"digabz5",
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"text": [
"Random mutation is just that. It's not driven by a response to some change in the environment. By abusing antibiotics, those bacteria that survive are guaranteed to have a resistance they pass on. If bacteria were to develop a resistance randomly, the chances of the the resistant strain becoming dominant is much, much less.\n\n[Here's a video of resistance development.](_URL_0_)",
"Bear in mind that most possible mutations are bad for an organism, most of the rest are neutral, and very few are actually good. \n\nFurthermore, what counts as a good mutation depends on the environment the organism finds itself in. \n\nImagine that we liberally use an antibiotic so the organism is very likely to encounter it. Now a mutation which makes the organism resistant to the antibiotic is far more likely to be a \"good\" mutation, even if it has some otherwise negative consequences, and that mutation is likely to spread throughout the population. \n\nHowever if the antibiotic is used sparingly, that mutation, if it arises, is likely to be, overall, a \"bad\" mutation, or at best neutral, so will be far, far less likely to ever spread throughout the whole population. \n\nSo although mutations are random, and a mutation to make the organism resistant is just as likely to occur if we over-use the antibiotic or not, the mutation will only take hold in the population if it actually provides a net benefit to the organism, and this is only likely to happen if we overuse the antibiotic.",
"Antibiotics aren't the main thing bacteria in the world are competing against. Mostly they are competing against other bacteria. It is very possible that a bacteria out there just evolved a mutation to be resistant. In fact it has probably happened millions of times. But then that bacteria wasn't got out competed for whatever food source it was on because that mutation wasn't that helpful, and perhaps even cost a bit of resources. So now it is dead, or at very least rare. When you encounter a bacteria in the wild, it probably isn't that one.\n\nNow, scenario 2. That bacteria makes the same random mutation, but now it is in an environment rich in antibiotics... say a river downstream from a farm that heavily uses them on beef.\n\nNow it isn't a level playing field. The other versions of that bacteria are struggling. That means open buffet for the one bacteria in a billion that is resistant. Soon that whole stream only has resistant bacteria. Billions of them. Even worse, bacteria has ways of exchanging dna with other bacteria, which they would do anyways, but now it is way more likely to be exchanging the resistant defense than some other random dna.\n\nNow when you encounter the bacteria, instead of a 1 in a billion chance that you catch the resistant strain, you are almost guarenteed to have a resistant strain. Bad for you. \n\nPlus, now that everything is a super bug, the only ones that get advantage are those that have anothrr mutation to be even tougher.\n\n_URL_0_\n\nThis is the best video I've found demonstrating it. Watch a bacteria go from completely contained by antibiotics to resistant to a concentration 1000 x higher right before your eyes. If someone happens to get exposed, they better hope it is a strain on the right and not a strain in the middle that has had a chance to buff itself."
]
}
|
[] |
[] |
[
[
"https://www.youtube.com/watch?v=plVk4NVIUh8"
],
[],
[
"https://youtu.be/yybsSqcB7mE"
]
] |
|
194rwj
|
how does the government track people downloading illegal music?
|
Also, if possible, please explain how they can track who is visiting sites offering illegal downloads.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/194rwj/eli5_how_does_the_government_track_people/
|
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"text": [
"They don't bother to track who visits sites that offer illegal downloads since it it too hard to know what they downloaded.\n\nBut bittorrent, one of the most common file sharing methods, requires the computers to connect to lots of other computers using bittorrent in order to get all the different parts of the file. It is easy to set up a computer that joins this network and look at what computers is asking it for parts of a file that is illegal to download.\n\nThen they ask their internet providers for the name of the owner.",
"I am not aware of any evidence of any western governments tracking 'illegal' downloads. Most file-sharing is not 'illegal' in the sense of committing a crime that harms society in general (such as theft or assault). But it does breach copyright laws. Breach of copyright is a *tort*, a civil crime in which an individual who is wronged can sue for damages. In order to sue for damages, evidence that meets certain standards must be acquired. \n\nLarge trade organisations, copyright enforcement groups and smaller security firms seeking to earn a quick buck monitor file-sharing downloads in order to obtain the details of participants.",
"As far as I know, they don't. It would be too much effort for something with too little of a return.",
"The government doesnt do anything, its all businesses who do the tracking and lawsuiting.",
"When you torrent something, you don't download the whole file at once (that would be to hard to move around, and really easy to track). Instead, the file is broken up into hundreds or thousands of little pieces, and for each piece you tell the network \"Hey! I'm downloading this piece of this file,\" and the torrent client of someone who's \"seeding\" sends it to you. \n\nJust watching you, this doesn't look too different from any other peer-to-peer activity, like playing online games.If someone wants to know who's pirating a file, there's something else that they do: they do the same thing as you, and tell everyone to send them pieces of this file. Then, they make a list of everyone who did so, and accuse them all of downloading illegally.\n\nIf your ISP wants to watch you for torrenting (which some in the US now do) they have a different way to check: they watch your uploads. It's pretty clear when you've torrented something, because you're now sending bits of the file to loads of people on the internet."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
|
18zrhf
|
French Military perspective of the French Revolution
|
I am not completely certain this has not been answered before skimmed briefly French Revolution posts...apologize if this has been posted previously...I am curious about French Military that helped/aided the American Revolution what was their perspective/understanding and such of the French Revolution taking place back home...
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/18zrhf/french_military_perspective_of_the_french/
|
{
"a_id": [
"c8jjwhi"
],
"score": [
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"text": [
"Much of the military leadership was aristocratic, and the anti-establishment views of the revolution caused an exodus in the chain of command at the outset of the French Revolution. \n\nHowever there were a number of military leaders that *did* stick around, the most notable that you may know of being the Marquis de Lafayette, whose enlightenment readings, and participation in the American Revolution, made him optimistic about the French Revolution. He served in the 1789 Estates General, and was made commander of the Parisian National Guard, which intervened on behalf of the Royalty during the March to Versailles. He ultimately tried to flee the radicalization of the Revolution for his aristocratic, pro-royalty leanings. \n\nIn terms of the actual soldiers who fought in 1778 - 1783, I'm not quite sure of their composition in terms of class outside of the officer corp. There are some well known Generals/Admirals of the time, but one died before the revolution, several lower ranking ones packed up and became emigrés, and yet still others ran the risk of (or did) face the national razor during the Reign of Terror. The actual role of the military drops off after much of the army was disbanded in 1784 for financial reasons. Besides a spattering at the outset of the revolution, it doesn't return in force until 1792/3/4 when outside pressures begin to mount. Even then, the composition and impetus changed dramatically, especially after the levee en masse. \n\nIt's actually shockingly difficult to get a read on what commanders truly thought of the French Revolution. In the case of Lafayette and the Comte d'Estaing (the Admiral that led the First French intervention following the treaty) they were ideologically on board in that they recognized the degree to which the system needed reform, whilst simultaneously being wed by birth to the existing hierarchy of French society. When the fighting broke out, the nobles were explicitly targeted and implicated in the violence, and inevitably caught between two worlds. In many cases the aristocracy were guillotined for much less than what Lafayette did when he ordered that a troop of National Guards open fire on san culottes, or forcibly turning the marchers out of the Palace of Versailles during the October March. Yet during the radicalization only old ties, rather than new actions, damned them. In the case of Philipe Egalite, the brother of Louis XVI, he was the swing vote that condemned his brother to the blade, yet he still became suspect a year later. There was also a fine line to be walked between risking support of the Revolution and alienation of hard-won Royal favor - especially when trying to decide which would be more valuable in the long run.\n\nSo, in short, there is very much a contextual element to take into account when asking a question like this. It really depends on when you ask the individual. Lafayette's views of the Revolution changed markedly, as did many other aristocratic supporters who weren't necessarily \"assured\" or \"fervent\" in their consent of the Revolution."
]
}
|
[] |
[] |
[
[]
] |
|
1lxrg5
|
What was the differences in music such as Metal in West and East Germany?
|
Just to clarify, I am just using metal as an example. Really, I mean just the differences in music in general.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1lxrg5/what_was_the_differences_in_music_such_as_metal/
|
{
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"cc3th62",
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"text": [
"I don't know if the bands are comparable at all, but the scorpions were from West Germany, and 5/6 members of Rammstein are from Easy Germany. There is a bit of a gap in eras when they were prevalent, but those are some examples of a band from East Germany and a band from West Germany",
"Made a distress call over at /r/metal, hope somebody shows up\n\nThe only thing I'm sure of is that the difference must have been huge: on one side metal was being smuggled through the border, on the other side metal was flourishing and laying the foundations for many a genre in the decades to come. Seriously, mid 80's west german metal is one of the best things to have ever happened to heavy metal",
"If you mean in the time when East Germany was still a communist state, then Metal was rare in the East because the authorities weren't keen on Western music styles.\n\nFor example, the band [Macbeth](_URL_4_), founded in 1985 at first played illegally, as they hadn't got a \"Spielerlaubnis für nebenberuflich tätige Amateurtanzmusiker, Berufsmusiker und Kapellensänger\" (Performance permit for part-time working amateur dance musicians, musicans and choir singers). After the support from a 81 year old music professor from the Weimar college of music, they finally got this important piece of paper. They played in German, while most metal bands from the west had English lyrics, while playing in English wasn't allowed. [Here is a demo from 1985](_URL_1_). \n\nAfter a number of successful concerts in 1986, a concert in Erfurt brought them to grief. The police didn't allow them to play more songs then planned, and the fans became angry. The Stasi agents who were present at the concert reported \"The concert had been a prominent example of western decadence and hooliganistic behavior, and didn't comply with the high level of socialist art and music policy\". They proposed \"measures should be taken to discipline or eliminate the band\".\n\nAlthough they didn't loose their permit, they were no longer allowed to use the name Macbeth, their touring truck was declared unfit for road use, and they could no longer use their training room. The lead guitarist was called up for the military. They continued playing under the name \"Caiman\", but a few months later the charismatic singer, Detlef Wittmann, was arrested and put in prison on a made-up charge. He was only released after the reunification, but committed suicide soon after. The band took up their old name, and still exists. [This](_URL_2_) is a trailer for their recent \"Stalingrad trilogy\".\n\nIn general, GDR pop music was more tame, and critical texts were not allowed. [This](_URL_0_) is a rare 1974 GDR music video starring Nina Hagen with the band Automobil, before she moved to West Germany. [This](_URL_3_) is what she looked and sounded like four years later, in West Germany.",
"Interestingly enough, many of the metal bands in West Germany were popular across the wall. In Berlin, in particular, when they allowed some people to cross sides for shopping and whatnot, these grandmothers would smuggle LPs back in via the lining of their luggage [~~I'll source this tomorrow~~, mentioned [here](_URL_2_) as well as in other interviews for you googlers]. What's commonly accepted as the first metal show (featuring non East Berlin bands) in East Berlin happened in 1989, featuring [Kreator](_URL_1_), Tankard, Sabbat (UK) and Coroner; with Kreator and Tankard both being German: from Essen and Frankfurt, respectively. Kreator has, in years since, commented that all the fans in attendance knew all the words to the songs despite the music being banned. \n \nThis does take some context, in that metal is a global genre, even in countries that strictly outlaw it. Iraq, for example, has Acrassicauda (subject of a [documentary](_URL_0_)) who have since left the country and toured America with, oddly enough, German band Destruction. \n \nApologies to all if I'm getting my east/west mixed up."
]
}
|
[] |
[] |
[
[],
[],
[
"http://www.youtube.com/watch?v=ZebPEmWh7tE",
"http://www.youtube.com/watch?v=qIIlSjO_wYc",
"http://www.youtube.com/watch?v=DwoBd3sMGCY",
"http://www.youtube.com/watch?v=4HLAfX1Xtwk",
"http://www.metal-archives.com/bands/Macbeth/45588"
],
[
"http://en.wikipedia.org/wiki/Heavy_Metal_in_Baghdad",
"http://www.metal-archives.com/albums/Kreator/Live_in_East_Berlin/14445",
"http://www.redbullmusicacademy.com/lectures/alex-barck--jazzy-sensation"
]
] |
|
24xuaz
|
how can fruit that costs $2 in us food shops cos $100 in japan?
|
How is this possible, surely fruits can't me that hard to produce/import in japan?
Reference: _URL_0_
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/24xuaz/eli5how_can_fruit_that_costs_2_in_us_food_shops/
|
{
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"chbplgh",
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],
"score": [
12,
7
],
"text": [
"Those are not ordinary \"let's have a snack\" fruit but meant to be given as very exclusive gifts. Every one of those fruits are in some sense \"perfect\", just look at how identical the grapes are. That's a particular quirk of Japanese culture.\n\nRead more about it in this [BBC article](_URL_0_).",
"The $100 watermelon is exclusively given as a gift. Everyone knows it's expensive and would never buy it for oneself (you can get a $8 watermelon very easily), but when someone shows one off at a party everyone gets excited and talks about how it looks. Kind of like a Louis Vuitton bag costs $2000, but you can get a $20 generic one that will work just fine.\n\nAnother factor is promotion. The $100 watermelon gets a lot of free advertising and news promotion. The person (company) that buys and sells the first one of the year also gets a lot of free promotion. Finally, the price of fruit at the supermarket is probably higher because people might imagine the $8 one is a good value because it's not $100. \n\nFruit does cost more in Japan, but domestic production is protected by tariffs, labor is expensive, and farms are small and inefficient. Generally, a 50 cent apple in the US goes for about $1.10 in Japan."
]
}
|
[] |
[
"https://www.youtube.com/watch?v=fR6GefDZWeQ"
] |
[
[
"http://www.bbc.com/news/world-radio-and-tv-17352173"
],
[]
] |
|
hbgyd
|
Energy generation: is our sun the ultimate source? If not, when and why would another source be preferred?
|
As a layman, it seems that despite current technological limitations, solar energy would be the most fruitful to develop. Is that true? What barriers are present for this technology? What do you see for the future of solar?
|
askscience
|
http://www.reddit.com/r/askscience/comments/hbgyd/energy_generation_is_our_sun_the_ultimate_source/
|
{
"a_id": [
"c1u37q2"
],
"score": [
2
],
"text": [
"A lot of things are meant by solar. But I'll just say that the sun is the only energy *input* to our planet. Fossil fuels are stored solar energy. Fission and fusion is technically a limited source of energy, even if not in practice. "
]
}
|
[] |
[] |
[
[]
] |
|
9ha1fk
|
Do mammals, specifically monkeys, realize that mating leads to offspring?
|
Edit: Was brought up in class
|
askscience
|
https://www.reddit.com/r/askscience/comments/9ha1fk/do_mammals_specifically_monkeys_realize_that/
|
{
"a_id": [
"e6f1hny"
],
"score": [
9
],
"text": [
"No, the two events are too far apart to form a connection. They also don't realise that they are pregnant and about to give birth to a baby, they just \"feel like\" finding a safe nest all of a sudden when they are about to give birth due to hormonal changes. In subsequent pregnancies they may remember that having a big belly with a kicking fetus in it means babies will appear soon, but generally animals are not very self aware and lack a deeper understanding of cause-effect."
]
}
|
[] |
[] |
[
[]
] |
|
4xxg2y
|
For how long did "Roman" and "Etruscan" persist as distinct, living cultural identities in ancient Roman society?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4xxg2y/for_how_long_did_roman_and_etruscan_persist_as/
|
{
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"text": [
"I'm not a massive expert on Etruscans or anything, so if someone has some more specialised knowledge, please chip in. I don't think we can pinpoint any specific time when Etruscan identity stopped existing, because of the problems of defining what cultural identity is and how do we track the existence or disappearance of cultural identities with the sparse evidence we have. \n\nThe 'Romanization' of Erutria began slowly after the conquest of Veii in 396 BC. From there on, we can see changes in Etruscan material culture, religious rites and language that betray the adoption of Latin influences as a result of Roman expansion and implementation of Roman infrastructure (road networks, centuriation etc.). This process intensified with the defeat of Caere by Romans in 274-3 BC, after which all of Southern Erutria was under Roman influence, and the full integration of the Etruscan areas into the Roman sphere was when Augustus created a Roman adminstrative region Regio VII out of them. During the Middle Republic, it seems that some Etruscans still deemed it important to articulate a distinct cultural identity from the Romans - for example, see [Michael Taylor's paper](_URL_0_) that points out that the Etruscans in Roman military preferred to use distinctly Etruscan style funerary monuments that stood out from those of their Latin comrades. By the time of Augustus, however, Etruscan culture was almost gone; the language was hardly spoken and written, and the old characteristics of Etruscan society had disappeared. For example, the near equal status of women slowly disappeared as the Etruscans started following the social norms of Roman society, as we can see from the diminishing visibility of women in Etruscan art and funerary iconography, and by the early empire we simply cannot distinguish an Etruscan tomb from a Roman one. We know that the Emperor Claudius (10 BC – AD 54) was perhaps one of the last people who could read and write Etruscan, and he compiled a history and dictionary (Suetonius, *Life of Claudius* 42.2; these works are now lost) of the Etruscan language when it was dying out. We also know from Suetonius (*Life of Claudius*, 26.1) that the first wife of Claudius, Urgulanilla, was Etruscan. She was just one of the few notable people in late Republican and Julio-Claudian Rome that the literary sources call 'Etruscan'. What it meant to call someone 'Etruscan' during Claudius' time or Suetonius' time is unclear - at this point almost no-one spoke the language and centuries of intermarriage most likely meant that there weren't any 'pure' Etruscan lineages anymore. Could Urgulanilla perhaps still speak Etruscan, or was his family simply promoting its identity as Etruscan? \n\nBecause, long after Etruscan culture was completely assimilated to Roman culture, many Roman families liked to lay claims to Etruscan ancestry and early Etruscan kings since it gave the family status as ancient elite. For example, this [chair known as the Corsini Throne](_URL_1_) is as late as 2nd century AD and it was discovered from the villa of a wealthy Roman family. Its made in an archaic, Etruscan style that is clearly meant to promote the Etruscan heritage of the family - whether there's any truth to their claim or not is not known, or probably not really important. Also, there were priestly colleges and divination experts that continued to practice a distinctly Etruscan form of rites, based on ancient Etruscans texts, all the way to at least 5th century AD (and these people might have actually preserved the knowledge to read Etruscan even after Claudius).\n\nSo, in conclusion; people continued to identify themselves as 'Etruscans' and use Etruscan cultural symbols long into the imperial period, and some aspects of the Etruscan culture lived on and continued to be celebrated specifically as Etruscan culture. But, I'd imagine the culture as distinctly different from Roman culture - and people living according to that culture - died out already during the Republic. "
]
}
|
[] |
[] |
[
[
"https://www.academia.edu/16608087/Etruscan_Identity_and_Service_in_the_Roman_Army_working_paper_",
"https://s3.amazonaws.com/classconnection/838/flashcards/7021838/jpg/3084-14A2D0AF76238EE0E43.jpg"
]
] |
||
5bdrul
|
how to deal with depression as a friend/spouse/relation?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5bdrul/eli5_how_to_deal_with_depression_as_a/
|
{
"a_id": [
"d9nppjp"
],
"score": [
3
],
"text": [
"Depression is complicated, and to be honest, the only thing you can do is be there for them and try to help them if they get frustrated or upset. The only thing is, don't go over the top and be that guy who is always saying shit like \"You okay? Need anything? I'm here for you.\" Just be a bro (or lady bro) and be there without saying it."
]
}
|
[] |
[] |
[
[]
] |
||
a1dagx
|
I just finished reading an 1803 English novel that mentions Mexico. I had thought that the name was rarely used to refer to what's now Mexico before it became independent. What can you tell me about the use of the name "Mexico" for all of New Spain before independence?
|
Since the context is the different places that a grizzled sailor has sailed to, I think we can be sure that the passage refers to New Spain in general, rather than Mexico City, which is landlocked.
EDIT: Here is the passage in question, from *The Romance of the Pyrenees* by Catherine Cuthbertson:
"Thomas, indignant at a punishment his heart told him that he deserved not, quitted England; and, as his native and much-loved Albion lessened to his view, he rashly made the most solemn and awful of vows never more to return. On his voyage to America the transport he was in was wrecked: many of the crew and convicts perished, while he with a few other individuals were saved from the fury of the storm by a Portuguese merchantman on its way from Mexico to Lisbon."
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/a1dagx/i_just_finished_reading_an_1803_english_novel/
|
{
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"So lets start from the beginning, the origin of the word \"Mexico\" comes from the capital city of the Mexica's (popularly know as the Aztecs), one of the constitutent members of the Triple Alliance, composed of the Alcolhuas from Texcoco and the Tecpanecs from Tlacopan, and the Mexica (the people of Mexi) from Mexico-Tenochtitlan (Place of the Mexica-Land of Tenoch).\n\nUpon the defeat of the Mexica, Cortez rebuilt the city into the image of a Spanish city and named it simply Mexico-City (redundant name since the \"CO\" particle denotes a city (altepetl) already in nahuatl).\n\nNow, in time Mexico would become the cultural and commercial center of the Kingdom of New Spain, so for example in 1551, prince Philip gives out the necessary papers for the foundation of the \"University of Mexico\" which prints texts like \"3 latin dialogues from Francisco Cervantes and Salazar\" as far back as 1554, in which they talk about things like \"Mexico (the city) and its surrounding territories\", things like the \"Royal Audience of Mexico\" also start cropping up as Institutions in what was officially New Spain.\n\nThe term becomes common to describe the inhabitants as early as the 16th century, so for example Bernardino de Sahagun writes in the prologue of his 2nd volume of his \"Historia General de la Nueva España\" (translation from spanish by me):\n\n > \"Certainly it would be very profitable to make a work so useful for those who wanting to learn this *mexican* tongue, like Ambrosio Calepino did for those wanting to learn the latin tongue and the meaning of its vocabularies... \"\n\nFast forward to the 18th century and you have people like Francisco Javier Clavijero, Sor Juana Ines de la Cruz and Luis de Gongora y Argote writing about the \"mexicanity\" (mexicaneidad) of the territories, so for example, Clavijero writes in his \"Historia Antigua de Mexico\" (translation from spanish by me):\n\n > And so in the public government as in the domestic of the *mexicans which *we** are going to now expose* in this book you can see the characteristics of political discernment for the sake of justice, love and public good...\n\nHere we also see the early tradition of linking the old prehispanic empires to the new \"mexicanity\" that Clavijero and many other thinkers of the time are beginning to take as their own, see here when talking about the Mexicas and the Triple Alliance:\n\n > The nobility of *Mexico* and the entire Empire was divided in several classes which the spanish mistook under the name of \"cacique\". Each class had their rights and markings such that with even the humblest of dresses his position was known at first sight.\n\nParticularly funny to me is the trip of [Hasekura Tsunenaga](_URL_3_) to Spain in1614, as on his way he travels through Mexico, and so far as I can tell (though I dont have official sources on this, as my Japanese is still pretty basic), its at this time that the phonetic meaning of Mexico [is coined for Japan as \"Mexico\"]( _URL_0_), note there is a phonetic kanji for \"Mexico\" (メキシコ), but not for \"New Spain\" (ヌエバ エスパーニャ)\n\n\nAs even Japanese sources, and on this I apologize to the mods for using the japanese wikipedia, but the [Japanese embassy in Mexico text's](_URL_1_) are in spanish which doesnt properly convey the context of him entering New Spain through Acapulco, to \"Mexico City\": [出航から3か月後の1614年1月28日、アカプルコ入港。3月4日、使節団の先遣隊がメキシコシティに入った](_URL_2_)",
"*Had to do some source digging for this one, only got to it now. u/pizzapicante27 already covered some points which I'l expand on.* Most question on New Spain here are on the 16th century, so I'm glad for a chance to talk about the 17th century which even in academia is less discussed – and my actual period of research. \n\nAs a **short version**: You're right that Mexico mostly meant the City of Mexico in colonial times; and adopted as the independent country's name only in 1821. But there are at least two other meanings for Mexico for larger regions that would fit your passage: one for the Gulf of Mexico (17th c.) and one for pre-colonial Mexico (18th c.). In addition the name “mexicanos” for the indigenous inhabitants of Mexico City was gradually taken up by creoles (descendants of Europeans and native people). \n\nI'll go into these semantic changes now, and connect them to larger trends in the development of a “creole patriotism” in the end.\n\n\n## Origins\n\nAlthough it's often difficult to distinguish between pre-colonial and colonial usage, most commonly Mexico was used by the Nahua for the Mexica capital city of Tenochtitlan. This use continued in colonial times for the colonial city of Mexico City, which was built on the former Tenochtitlan following its conquest through the Spanish. \n\nSo while Mexico then had a very local meaning, the term \"mexicanos\" was often used by the Mexica to refer to themselves, meaning the inhabitants of Tenochtitlan and Tlatelco. The Mexica by the late 15th century dominated the Triple Alliance in the Valley of Mexico, consisting of the Mexica, Acolhua and Tepaneca. This usage of Mexica was taken up in colonial times by the Spaniards to refer to the Mexica, or more generally to speakers of Nahuatl (then called \"mexicanos\").\n\nThere are many differing translations of \"Mexico\", from Nahuatl. One of the most accepted ones today is \"the navel of the moon\", from \"Metzxico\": metz(tli) (moon) and xic(tli)(navel, centre), used by Alfonso Caso in the late 19th c. amongst others. This meaning has been extended as a way for the Mexico to refer to their capital as the centre of their known world. Other interpretations connect the name to specific deities.\n\nDuring the colony some creoles (Europeans born in the Americas) and Spaniards of colonial Mexico used the term for themselves - as a way to distinguish an upcoming \"creole Mexican\" identity from a European/Spanish one. The leaders of the the wars of independence were looking at different terms for the independent nation; only with the Plan de Iguala in 1821 was the name of Mexico officially adopted for the country, drawing on its centuries-long identification with the Mexica and the mexicanos, but also on a long tradition of creole scholars highlighting New Spain's pre-hispanic past. \n\n.\n\n# Mexico for Mexico City\n\nThe name for modern-day Mexico City changed quite a bit during the 16th century, depending on which group one looks at, with „Mexico“ just one of the options. Barbary Mundy has traced these complex changes: On the one hand, already Cortés had called it a „ciudad“ in his letters. This continues when it received the official city title by the Spanish Crown in 1548 (a special privilege) and it was called only „Ciudad de México“ by the Spanish city council (cabildo) from 1545 onwards. \n\nOn the other hand at least throughout the 16th century the name „Mexico Tenochtitlan“ continued to be used, both in official letters from Spain and in documents of the indigenous cabildo. Indigenous elites also used „Ciudad de Mexico Tenochtitlan“ in order to differ it from the sister city of Tlatelolco – some would continue to speak of Mexico Tenochtitlan into the 17th century. For you question this means that Mexico *was* used from the start for the colonial capital; but also that the name for even the city was adapted by different groups, with the pre-Hispanic „Tenochtitlan“ still in use for decades at least.\n\nThe next shift in meaning comes when Mexico starts to be applied not only to the city, but also to surrounding areas (roughly the Valley of Mexico) – at least in Spanish, probably less so in Nahuatl. This is important because this meaning would stick for centuries, and in some ways until today. Apparently it is still not clear when this usage became common (as James Lockhart and Susan Schroeder argue). But most scholars seem to agree that it was sometime in the 17th century. So while the indigenous scholar Chimalpahin writing in the early 17th c pretty clearly meant only the city with „Mexico“, creole scholars towards the middle of the century used it already in the larger sense. This shift has to do with an increasing creole influence and creole patriotism in New Spain.\n\n\n\nSome short background on „creole patriotism“ will come in handy here. The term was popularized in academia by D.A. Brading and others and is often used in the context of Latin American independence wars – in colonial times creole elites had had access to high posts and privileges, but the highest posts like Viceroy and archbishop were mostly closed to them and open only to Spaniards. Grievances over these and economic shortcomings are described as a major reason why creole elites would eventually lead the push for independence. What's less well known is that a form of common identification of creoles with their American home regions (or patriotism) had started to develop much earlier on some parts of Spanish America. New Spain/Mexico is usually seen as special in that according to some scholars, creole patriotism had come up in Mexico City as early as the early 17th century.\n\nOne famous example of this is Bernardo de Balbuena, who in his aptly-titles *Grandeza mexicana* from 1604 would posit Mexico City as a major center, at least on par with European metropoles. This is a very different perspective from contemporary Spanish writers who would for a long time continue to describe the Americas as „backwaters“, whose climates and food would corrupt people who moved there. Balbuena writes\n\n > [México] is a city of notable order\n\n > Where the Spanish language is spoken\n\n > More purely and with greater elegance.\n\nApart from Balbuena's pride in Mexican Spanish here - note how Mexico still refers to the city only and not its surroundings. By this point already, Mexico City (“México”) had become for many creole elites a main example of the importance (and maybe even superiority) of New Spain. After all, this “heart of the world” lay between the important Asian trade – via the Spanish Philippines – , as well as the South American and Mexican silver – the life-blood of the Spanish empire –, which it connected to Europe – through Sevilla and later Cádiz. The central place of Mexico as economic and administrative centre is reflected in the reverence creole elites like Balbuena paid to it.\n\n\n# Mexico for the Gulf of Mexico (“Seno Mexicano”)\n\nSome changes take place in creole views by the late 17th century, which we're jumping to now. At this time two best-known scholars in New Spain – and probably for all of Spanish America – were Carlos de Sigüenza y Góngora and Sor Juana Inés de la Cruz. For our topic Sigüenza y Góngora is more relevant, since he was actually strongly influenced by indigenous writings from his large archive. Unfortunately he did not finish his history writings on pre-Hispanic times, so I'll look at another short work of his regarding his use of “Mexico”, the “Alboroto y motín de los indios de México” from 1692.\n\nThe Alboroto is Sigüenza y Góngora's first-hand account of the Mexico City riots of 1691. These were carried out by parts of the city's population due the authority's mismanagement of a lack of food (and other reasons) – so the title's “México” clearly follows the traditional use, meaning the capital city. Overall in his account, mostly Mexico refers to the city and for Siguenza the larger territory is “New Spain” or the “Viceroyalty”, so far so good. More generally, Siguenza and Sor Juana are usually seen as creole scholars proudly upholding their patria of New Spain. Another work of his is titled “Paraiso Occidental\" and focuses once more on Mexico City, as an earthly paradise – extending the ideas of Balbuena mentioned above.\n\nThen again, I did find two passages that would fit better with your question. In these Siguenza discusses the “Seno Mexicano” in connection with corsar ships that were then often doing raids in the Gulf of Mexico. \n\n[This map by José Dias Portaly shows](_URL_0_) roughly the size of the Seno Mexicano corresponding the the Gulf of Mexico. Not that at the time this would have included Spanish possessions like what was then New Mexico, Tejas and parts of Florida. It also shows that at least in New Spain the term was still in use 100 years later in 1787, so quite close the your book's publication. Although I don't know enough about English literature to judge if it was in use in England at that time, it seems very probably since the term had been floating around for more than 100 years. So this seems like a good contestant for what you're looking for, especially given the maritime context of Siguenza's passages.\n\nI'd also add here the Siguenza was an expert on New Spanish geography, who made state of the art maps of waterways, and of northern regions during an expedition there among other things. So that his use of terminology can be seen as quite representative for intellectuals there at the time. And also that even before Siguenza “Mexico” had started be used only for northern regions like those mentioned above, New Mexico and further north, that would definitely not be part of modern-day Mexico. A transposition of the meaning of “Gulf of Mexico” - for the Seno Mexicano - into English as “Mexico” seems like a good option for your question then.\n\n \n\n"
]
}
|
[] |
[] |
[
[
"https://jisho.org/search/%E5%A2%A8%E8%A5%BF%E5%93%A5%20",
"https://www.mx.emb-japan.go.jp/files/000132661.pdf",
"https://ja.wikipedia.org/wiki/%E6%85%B6%E9%95%B7%E9%81%A3%E6%AC%A7%E4%BD%BF%E7%AF%80#%E4%BD%BF%E7%AF%80%E3%81%AE%E6%97%85%E7%A8%8B",
"https://en.wikipedia.org/wiki/Hasekura_Tsunenaga"
],
[
"https://www.loc.gov/resource/g4392c.ar171500/?r=0.081,0.133,1.153,0.521,0"
]
] |
|
5x6bjx
|
why do they still make complicated stop-motion movies if there is more-efficient animation software available?
|
Why do they still make complicated stop-motion movies, like Kubo and the Two Strings, if there is more-efficient animation software available?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5x6bjx/eli5_why_do_they_still_make_complicated/
|
{
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"text": [
"Because it has a very particular style. It's like why do people still paint with paint and brushes when they could do it on a computer, or why do people buy records when they can just get an mp4. New and efficient doesn't mean better in every way.",
"Why do people paint when photography exists?\n\nSometimes the medium or methods used are more important than the final product."
]
}
|
[] |
[] |
[
[],
[]
] |
|
39ewlz
|
Where on the Reichstag was the famous photo with the soviet flag?
|
I currently live in Berlin and recently went to the top on the Reichstag building. I thought up there it might say where the image of the Soviet Soldier was snapped but it did not. I think, based on the buildings in the background it is looking over the city and if it wasnt rubble you would see the Brandenburg Gate in the background, can anyone confirm this or know which way it actually is?
_URL_0_
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/39ewlz/where_on_the_reichstag_was_the_famous_photo_with/
|
{
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"cs2v93t"
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"text": [
"I'm not entirely sure but I think they are standing on the south eastern part and the photographer looks south slightly east. The corner you see at the bottom of the picture would be Ebertstr./Dorotheenstr. today. So roughly here:\n\n_URL_1_\n\nThe Brandenburg gate wasn't completely destroyed but heavily damaged. I think you can see one of the gatehouses on the picture but the gate itself pointed in another direction so you can't see the columns.\n\nCompare with the map here (I think shades of blue indicate degree of destruction): \n_URL_0_\n\nFor people who are interested two things of historical significance to this picture:\n\n1.) This was the second time they raised the flag. The first time there was no photographer present so they staged it again.\n\n2.) This is the unedited picture. In an edited version used for official propaganda purposes the guy at the bottom loses one of his wrist watches as this was an indication of looting. \n\nCompare both pictures here:\n_URL_2_ "
]
}
|
[] |
[
"https://reconsideringrussia.files.wordpress.com/2015/05/soviet-flag-reichstag-berlin.jpg"
] |
[
[
"http://www.alt-berlin.info/cgi/stp/lana.pl?nr=37&gr=5&nord=52.516265&ost=13.374636",
"https://www.google.de/maps/dir/52.5182905,13.3766687//@52.5182274,13.3771239,19z?hl=de",
"https://iconicphotos.wordpress.com/2009/04/22/the-red-flag-over-the-reichstag-2/"
]
] |
|
7sadaq
|
What makes the Magnetic South Pole and the Geomagnetic South Pole seperate locations, and why are they seperate?
|
Was watching CGPGrey's video [Who Owns Antarctica? (Bizarre Borders Part 3)](_URL_0_) and noticed that when he made a quick mention that there was more than one "South Pole", there was a Magnetic South Pole, and a Geomagnetic South Pole. What's the difference between Magnetic and Geomagnetic, and why are the two in seperate locations?
|
askscience
|
https://www.reddit.com/r/askscience/comments/7sadaq/what_makes_the_magnetic_south_pole_and_the/
|
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"text": [
"The magnetic south pole is where magnetic field lines of the earth are both vertical and pointing upwards (if you were standing there). Compare this to, say, Hawaii, where the magnetic field lines would be nearly horizontal to someone standing on the Earth. The magnetic north pole is where the lines are vertical and pointing *downwards*.\n\nTwo things: one, the South pole is actually the north magnetic pole sInce the South pole of our magnetic compass is attracted to it and opposites attract. Two, magnetic field lines \"point\" from North to south. \n\nNow, the geomagnetic pole is a hypothetical magnetic pole. If the earth were just a bar magnet, then the South geomagnetic pole would be where the earth-bar-magnet's North magnetic pole was. Essentially, it's trying to get rid of the complicated bits of the Earth's magnetic field and make it into a reasonable approximation. And that's what it is--it comes close to describing the actual magnetic poles, but it isn't as accurate. "
]
}
|
[] |
[
"https://youtu.be/DbKNlFcg02c"
] |
[
[]
] |
|
70onyr
|
Why are Scotch-Irish considered one group, and separate from English, when they are different countries with different beliefs?
|
My impression, as an American who has Scotch-Irish heritage, is they don't really like each other. They seem to have different religious beliefs, Irish are usually catholic and according to the front page most of the Scots are non religious.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/70onyr/why_are_scotchirish_considered_one_group_and/
|
{
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"dn4vrex"
],
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129
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"text": [
"I believe the confusion here stems from the usage of the term \"Scotch-Irish\" to denote the ethnic group in question. Scotch-Irish does not actually refer to a collective grouping of both Scottish and Irish peoples. Scotch-Irish is another (sometimes considered pejorative) name for Ulster Scots, which were a group of ethnic Scots who settled in Northern Ireland as part of an English state-sponsored plan to colonize Ireland and dispossess its landowners. So, in a simplified sense, Irish refers to ethnic Irish living in Ireland, Scottish refers to ethnic Scots living in Scotland, and Scotch-Irish (Ulster Scots) refers to ethnic Scots living in Northern Ireland. \nSource: Jane Kenyon, Jane Ohlmeyer, *The Civil Wars: A Military History of England, Scotland and Ireland 1638–1660*"
]
}
|
[] |
[] |
[
[]
] |
|
3jy4kl
|
why do so many news agencies cite reuters stories for their information? what's so special about reuters?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3jy4kl/eli5_why_do_so_many_news_agencies_cite_reuters/
|
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"text": [
"because it's either reuters or the ap that are actually getting the news. the other news agencies are just repeating what reuters or ap have already said since people tend to read local news more often. ",
"Most outlets reporting news can't afford to have a presense around the world. So they have to get a lot of their coverage of global news from a few companies that have extensive global networks of reporters, such as Reuters and Associated Press.\n\nAs an example, for most of the year, your average newspaper doesn't need to have a reporter in Ethiopia or Tajikistan. But if something newsworthy happens there, they want to report it. So they'll get the story from Reuters reporter who's there and go from that.",
"So why not cut out the middleman and get your news directly from AP or Reuters?",
"Every newspaper/radio- or TV-station uses the service of press agencies like Reuters, AP and a couple of others (AFP is based in France, dpa in Germany, etc...) and you pay a certain fee to use their reports for your stories. \nThen you usually rewrite the thing/throw in a few of your own sources/ do some more research / mix the information from several press agencies.\n\nThe reason the media does that is that your local newspaper can't afford a huge network of correspondents around the world (especially in more remote places) but they still want to inform you about the stuff that happens there.\n\nAnd there's nothing super special about Reuters - there are just one of the big players in the press agency game and have a network of reporters around the whole world, so they can cover almost everything.\n\n(My workplace has decided recently to Reuters because my boss thinks they are not fast enough compared to the others...I kinda miss Reuters - especially their pictures are usually good and they really cover almost everything)",
"What makes Reuters reputable is that their reports are extremely neutral. They just write like \"So, this happen in this country, this guy said this and this guy did that\" They didn't put their own opinions in it",
"Former journalist here.\n\nReuters and Associated Press (to use two big examples) are press agencies. Many, many news outlets pay either a subscription fee or buy a story off them for a one off price. This way, they don't have the overheads of sending a reporter to X location, and they get breaking news thanks to the huge network of local reporters these agencies hold. Reuters is fairly unique in as much as it has a massive news outlet presence, as well as a 'ticker' reporting service for the financial markets. This competes with Bloomberg and Dow Jones - part of the Wall Street Journal (now separate from the Dow Jones market) and is hugely successful.",
"You've already got enough basic information from others here, so I'll add to that. This might be longer than you're after, but hopefully you'll find some of it useful.\n\nFor a more in-depth explanation, a good book to read about how news works today is [The Flat Earth News](_URL_0_). I can't recommend this highly enough. It speaks specifically of the context of journalism in the UK, but its lessons translate perfectly to what's happened in the US, and the book's aged well - it's only become more important since 2009.\n\nUltimately, many news outlets in the past relied on AP and Reuters because it was a great source of reportage for those parts of the world where it might not make sense to have your own reporters.\n\nIn the era when every almost major city had two or three major daily newspapers papers, and the US had three television networks, for these outlets (and many magazines) international news was often a \"prestige\" expense; it might not be a money maker for every newspaper, news magazine, and television network, but if you didn't have it, it would make your operation seem less serious to the public, and make your entire news operation seem less credible.\n\nToday, AP and Reuters serve a different function. Faced with competition from low-expense outlets on the web, and the diminishing power of the big three US television networks, running an international news department is just another expense in an industry which is suffering loss after loss. Many cities are down to one daily paper, and some even less, with their newspaper of record not appearing every day. Smaller towns which were served by multiple newspapers in the past are even more likely to see contraction. Many of the US's major news magazines have long since ceased publication.\n\nMany news outlets don't just source their international news from AP and Reuters, they source as much news as they can from any source they can get. CGP Grey, someone best known for funny, brief explanatory YouTube videos, noted something I found very true in my own experience: the closer you are to a particular subject of interest, the more you notice that news reportage on it is incredibly wrong. This isn't limited to areas where one has a subjective opinion, such as politics, where if one is an extreme partisan for one major US party, everything someone of the other party says is automatically \"wrong\" or at least suspect. This includes just basic day-to-day science, technology, human interest, current events, and gossip stories. The basic facts are often wrong, the conclusions are often not sufficiently supported by the evidence, and they simply don't match what an \"insider\" to a particular field would agree properly describes the truth, even about non-controversial issues.\n\nThis is because most news outlets simply don't spend as much time and money on real investigative journalism as they used to. Companies and lobby organizations are notorious for sending \"pre-written\" news stories and videos about products and issues to various outlets, who will cover them with no further investigation, and will sometimes re-write them so superficially that they'd fail a plagiarism review for a high school paper. As far as the original authors of the pieces are concerned, this is fine, because they're not interested in getting credit for the piece, they're interested in getting information - usually quite biased - out there to the public.\n\nHere's an example of someone debunking the sort of corporate press release disguised as news: [EEVblog #751 - How To Debunk A Product (The Batteriser)](_URL_1_). Admittedly, this guy knows his electronics, and he's not afraid of technical terminology, but the basic point stands is that most of the basic claims made by the makers of this product were easily testable by anyone with a modest budget to grab two identical battery-dependent gadgets and a handful of batteries. They didn't, because outlets like PC World and others who carried this glorified advertisement need content, not a research project which requires time, editors, and a modest amount of money.\n\nSo, AP and Reuters benefit from the same sort of pressures that corporate press release distributors and lobbyist groups benefit from:\n\n* shortened news cycle\n* reduced news budget\n* significantly reduced news budget for international news\n* less \"home competition\" (newspapers in the same city, news magazines, and TV channels by people with limited options) driving prestige expenses\n* drastically more outside competition (internet, internet, internet, people with many, many more TV and VOD options than ever before)\n* more of a focus on amount of content rather than quality\n\nThis isn't to say AP and Reuters aren't good news services; they're certainly better than the barrage of advertisement-as-copy I've referenced. In a world where AP and Reuters are doing more and more of the international reportage for an increasing amount of English-speaking news outlets, however, this is problematic. It limits the amount of opinions we hear. Further, both Reuters and AP are largely defined by their desire to be as objective as possible, sticking only to facts. They're never perfect at it, being fallible organizations run by fallible humans, but you often need in-depth reporting by people with an opinion and experience, and who can contextualize a situation in another country for a domestic audience who may not fully appreciate it. AP and Reuters are also noted for their brevity, they were not traditionally intended for the job of replacing international news outlets' foreign correspondence, but rather supplementing them for more out of the way places (a polite way of saying \"less newsworthy to the US and the UK\"), or giving a gloss of international news to more local organizations which weren't equipped to provide it at all themselves.",
"As a fellow journalist who trusts Reuters and AP I think I can answer in ELI5 mode: \n \n\n\nWhen someone does something the right way for a long time you trust them. Reuters is news agency which proved itself in time for doing proper journalistic work so that's why everyone is trusting them. \n\nAnd continuing in ELI10: \nTrust is very important when you are working with information. Journalism is not some production in which you can just buy the best part for your assembly, it is very delicate field where you work with rumours, information which not always is true. And Reuters and AP have true information because they gained trustworthy relations with people who have first-hand access to very delicate information.",
"Television news kinda works the same way. Reporters across the country will make \"canned\" news stories about general interest stories then sell them to local television news to use as filler during news broadcasts. In fact, Conan O'Brien does a bit sometimes where he just compiles all the local news stations around the country using the same news story.... _URL_0_",
"Reuters is one of several \"wire services\" or news agencies. Its' specialty is to be on the ground first (or early) and send out stories other news agencies can publish. They do this via contracts and licensing agreements. The idea: We'll have reliable reporters on the ground, and you can pay us to publish our stories in your newspapers/magazines/websites/TV programs. The wire agencies are known for being neutral and accurate (but lacking in sizzle).\n\nUsually, if you read your local city newspaper (Which you should), local stories will be by local reporters, and national news will come from the wire. It's just easier that way.\n\nThere are two major wires, or three if you live in europe. The Associated Press (\"The AP\"), Reuters, and the Agence-France Presse (\"AFP\"). The AFP's seen better days, however. Reuters is owned by the massive conglomerate Thompson Reuters, which also owns West. It's in the business of information, be it legal, economic, or news.\n",
"Local television news stations also use services like these. The reports are written specifically for television and are used to fill local broadcasts when there isn't enough local news to cover. \n\nThat's why this happens: _URL_0_",
"Also begs the question: Why get your news from slanted news companies when you can just get it straight from Reuters or AP?",
"Reuters used to be an independent news agency .. Until 2008, when it was acquired by Thomson.\n\nIt is still considered by many to be the most independent and reliable.\n\nOver the years Reuter's agency has built a reputation in Europe and the rest of the world as the first to report news scoops from abroad. Reuters was the first to report Abraham Lincoln's assassination, for instance. Almost every major news outlet in the world currently subscribes to Reuters. Reuters operates in more than 200 cities in 94 countries in about 20 languages.\n\n",
"Does anyone know of any good documentaries about the media? I know of Manufactured Consent and Outfoxed. Any other good ones?",
"What u/Pontus_Pilates is true but if you're asking about Reuters specifically it could also be because Reuters' policy is to report unbiased facts and you will see something like 'said an official' or 'reports say' after almost every statement.",
"Note: I worked at AP.\n\nAs many people here posted, AP and Reuters are wire services, which distribute news stories for other people to publish (wire is the term for the distribution method). They've got a full staff of reporters in various locations around the world doing investigative journalism, but there's more to it than that.\n\nOne important thing to note is that the AP, as its name implies, is an association of press. It's not a for profit company, but actually a non profit collective owned by its member newspapers.\n\nTo be an AP member, there are different levels of involvement depending on your level of usage and the type of organization you are.\n\nBut, the most important kind of membership are with local news organizations. To be a member, you pay a significant fee (often in the millions of dollars). In exchange, you get access to all of the news reporting that the AP generates itself, but also access to the wire, or all of the local reporting provided by its member papers.\n\nYou, in turn, are expected to provide your own local coverage for distribution on the wire.\n\nFor example, if there's a bombing in Boston, a small town paper in Cleveland might not have a reporter in Boston, but they'll be able to pick up the coverage that the Boston Globe created without having to send a reporter of their own.\n\nThen if something were to happen in Cleveland, for example a high school basketball player is getting attention from the NBA and is being talked about as a first round pick, that Cleveland paper would send its coverage of that on the wire so the other papers could use it.\n\nBecause the AP is a non profit focused on journalism, they don't have to worry about being motivated by money or only covering things that are profitable.\n\nHappy to answer other questions if anyone has them.",
"Hi, journalist here!\n\nReuters is not a newspaper like CNN or the BBC. There are groups that we call various things. At my old papers we called them \"wire agencies\". \n\nReuters hires mostly photographers, business experts, journalists, ect., but the real beauty is that they, along with other wire agencies like the Canadian Press and Associated Press, have a global dedicated network of freelancers that will buy anything newsworthy, if there's a demand for it. \n\nThe way Reuters works is that they constantly have a stream of incoming material through what we call the wire, really whenever I used the Canadian Press it was just a website. You can get photos, press releases, anything you want through them. If something important is happening and there's a demand for certain information, they'll let the people in their mailing list know: \"Reuters is looking for this\". \n\nMedia outlets like CNN/BBC/CBC whatever can then access this information and \"borrow\" it (not free, of course). Reuters, in the eyes of the people who use it, sort of works like a really efficient freelancer. \n\nNow, why use them? Because of their connections, networking prowess, and speed. And because it's cheaper to pay Reuters then it is to fly one of your own guys out to the middle of nowhere. \n\nAnd the final reason is because Reuters has created a standard of quality for themselves that cannot be beaten. Reuters, especially their business and foreign politics side, are the absolute best in the business. \n\nThese Wire Agencies also don't actually cost that much to operate, since they use so many free-lancers. In fact, I can't speak for Reuters, but the Canadian Press headquarters is a 1-floor office with a staff of less than 30 people. At least, that's about how many I saw when I toured there a few years ago. \n\nEDIT: Sorry, I forgot to mention, the language barrier is one of the best reasons why Reuters, the CP and the AP are so often cited. You see, your news paper may have a staff of 100 people but if some shit happens in Taiwan and nobody speaks Taiwanese, your paper will be screwed out of that story; unless someone who works for Reuters in Taiwan writes the story and translates it to English for you. ",
"So this discussion is meaningless? _URL_0_",
"Fun potential source of embarrassment and tangent I didn't find in the comments. It's pronounced Roiters. I didn't learn this until well after I should have."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[
"http://www.amazon.com/Flat-Earth-News-Award-Winning-Distortion/dp/0099512688/ref=sr_1_1?ie=UTF8&qid=1441628575&sr=8-1&keywords=flat+earth+news&pebp=1441628580979&perid=1CXBV0FJN33HY54D93YC",
"https://www.youtube.com/watch?v=4iEshd6izgk"
],
[],
[
"https://www.youtube.com/watch?v=TM8L7bdwVaA"
],
[],
[
"https://youtu.be/TM8L7bdwVaA"
],
[],
[],
[],
[],
[],
[],
[
"http://www.quora.com/Why-is-stock-market-data-delayed-by-20-minutes-NYSE-NASDAQ-to-the-general-public"
],
[]
] |
||
3mfczj
|
how do we map images from the non-visible color spectrum into an image we can see?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3mfczj/eli5_how_do_we_map_images_from_the_nonvisible/
|
{
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"cveji9p",
"cvejqcp"
],
"score": [
2,
2
],
"text": [
"Light exists on a spectrum, so even if we can't see it we can still tell that this part of the image has longer wavelengths and this part has shorter ones. We can shift these into a range we find useful. Just map all the short wavelength parts to blues and the longer ones to reds, or you can just sum up the intensity at each point and just make a monochrome image in some particular color.",
"Colour maps. A digital camera returns some value from it's sensor, and a computer relates that to some value it sends to a screen using a colour map, and we see a colour. There's really two ways to do this. \n\n\nOne way is to just map the intensity, how bright the light is in whatever invisible spectrum. This can be mapped to any arbitrary colour scheme you want. For example, the cliche [nigh vision goggles dark and light green vision](_URL_1_). Or the thermal camera [black=cold (less IR) white=hot (more IR).](_URL_0_) Or the also common thermal camera mapping where [more IR (hot) is red and less is blue.](_URL_2_)\n\n\nAnother way is just to map a non-visible spectrum onto the visible spectrum. Usually the lower frequency of whatever spectrum is being viewed shows red while the higher shows blue. Photos of space that look like [this](_URL_3_) are often timed colour mapped like this."
]
}
|
[] |
[] |
[
[],
[
"http://www.x20.org/wp-content/uploads/2014/04/thermal-image-man-breaking-into-warehouse-300x225.jpg",
"http://cdn.lightgalleries.net/4ebd8bde12cf2/images/Iraq_Perspective_BookEdit_0049-2.jpg",
"http://www.terrahope.com/videos/video-3.jpg",
"http://i.telegraph.co.uk/multimedia/archive/02357/eso-summary_2357457k.jpg"
]
] |
||
5e8bc0
|
Does the brain have a clock, like a CPU?
|
A CPU has a centralized clock which in which instruction(s) are executed in each clock cycle.
Neural oscillation, or "brain waves" are repetitive neural activities where the firing of the neurons are usually in synchronization with the oscillation. From what I've read, these are the following known waves and frequencies:
Delta wave – (0.1 – 3 Hz)
Theta wave – (4 – 7 Hz)
Alpha wave – (8 – 15 Hz)
Mu wave – (7.5 – 12.5 Hz)
SMR wave – (12.5 – 15.5 Hz)
Beta wave – (16 – 31 Hz)
Gamma wave – (32 – 100 Hz)
My question is, how do CPU clocks and brain waves differ? They both synchronize the operations being executed, and they are for the most part, central as well. A brain would better analogous to a GPU than a CPU, since it's massively parallel, but a GPU still runs on a clock.
One more question, would "overclocking" a brain (increasing the frequency) necessarily make it faster, like it would for a CPU?
|
askscience
|
https://www.reddit.com/r/askscience/comments/5e8bc0/does_the_brain_have_a_clock_like_a_cpu/
|
{
"a_id": [
"db0myfr",
"daav2fw",
"dab1v3m"
],
"score": [
2,
15,
5
],
"text": [
"The point everyone is making, that all neurons are clock-like blah blah blah, is all well and good, but how is it no one has mentioned the **Super-Chiasmatic Nucleus (SCN)?** It may not be the end-all be-all of the question but it's definitely very relevant. \n\n\nIf, biologically speaking, you're looking for a \"central clock\" this small group of cells located above the crossing (chiasm) of the optic nerves is most probably your best bet. Virtually all biological rhythms are checked against the time kept by this nucleus, and it fires in a highly precise, synchronized fashion, with each cell using both the other cells and you're own experience of waking every morning as a reference. It does not account for all the psychological perceptions of time we experience, but as for all non-conscious rhythms, the SCN is a sure bet.",
"A little knowledge is a dangerous thing.\n\nThere is no significant evidence for the brain having a clock, at least in any fashion that is comparable to clock in a microprocessor. There may be some neural behaviour that is based on rhythmic neuronal behaviour/oscillations, but that is not equivalent to the clock on a microprocessor. In order to understand why they are not analogous, you need to understand what they both are.\n\nA clock in a microprocessor is obviously based around a piece of vibrating quartz, a frequency multipliers and so on... but we can abstract it to a square wave generator, that is a voltage switching between high and low. The logic gates inside a microprocessor a built up of transistors, and they do not need a clock unit to work: an AND gate will perform it's function at any rate, up until the transistors simply do not have enough time to respond. HOWEVER, in order for large numbers of logic gates to work in parallel, they must be synchronized, both on the input (both inputs to an AND gate arrive at about the same time) and on the output (the output from an AND gate and and OR gate might need to arrive at another gate at the same time). This is, in essence, achieved using something like a 'register', which stores a binary value, and spits it out when it is asked, which is the next clock cycle. That is, the gate performs it's function, the value is put into a register, and then the next clock cycle, the register supplies that value to the next set of gates.\n\nThe brain does not work in a comparable fashion. There is no central clock. There are no registers. Neural function does not happen in a synchronous fashion. However, if one was to FORCE the analogy, it would be a network of logic gates with no registers. When a complex pattern of inputs (sensation) arrives at the input nodes of the logic gates, then perform their functions which then cascade as fast as the logic gates will allow through the network, and produce an output (movement).\n\nSo then, this might make you wonder what these EEG oscillations are? I think the most useful analogy is to simply think of them like the sound of your cars engine. When you car performs it's task, that task necessitates the generation of sound. Those sounds reflect the underlying task (low rumble: idle. Load roar: acceleration. Ticking: engine cooling) but they are not fundamental to the task. There are some neuroscientists who disagree, but I have never seen any actual evidence that proves that this is not the case.",
"I realize this is not the same as a CPU clock, but how does my brain know exactly how long it's been? For example, I can lay down and say \"I need a 25 minute nap\" and I wake up after 24.5 minutes. If I need to wake up at 5am, I wake up at 4:58, always within a minute or two max. How does it know? "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
5xaee8
|
Can physicists capture a gluon particle on its own, or even collect a pure sample of gluons, and would it be massless?
|
askscience
|
https://www.reddit.com/r/askscience/comments/5xaee8/can_physicists_capture_a_gluon_particle_on_its/
|
{
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"degjezh",
"degm6y4"
],
"score": [
7,
48
],
"text": [
"The closest thing to this is the currently-hypothetical [glueball](_URL_0_), which is a bound particle made only of gluons. It is expected to have a mass 3-5 times that of the electron. There is currently an American experiment called Glue-X which is developing the capability to produce and detect these (larger experiments like at the LHC are probably creating them but not detecting them).",
"Gluons and quarks are subject to the strong force. This makes them special because they can never appear by themselves. Their attraction to other strongly interacting particles is so large, that if you were to try and pull them apart to examine one by itself, the field lines connecting them would snap and create more particles which then serve to pair up the particles you were trying to pull apart. [Sort of a cartoon explanation obviously.]\n\nAnother answer mentioned glueballs. It is true that this is a particle in the standard model which would be made of nothing but gluons However, in practice, it is not really a particle so much as a \"intermediate broad resonance\", Because as a particle it is so unstable that its existence itself isn't really a sensible way to describe it. It is more like an intermediate state in a long near-instantaneous decay chain of QCD hadron states, which decay their way towards sort of stable particles like pions and truly stable particles like protons.\n\nHowever, interestingly, it is possible to imagine theories of QCD [The strong attraction] which do not have a light quarks. In that case, the glueball would kind of be the equivalent of the proton, meaning it is the stable form of matter in this theory sector. Furthermore, it is possible that this is realized in nature, but that we just do not yet see these interactions and particles. They could be related to dark matter, or be part of a meta stable \"hidden sector\" of particles and forces co-existing with our own, but only extremely weekly coupled to us (I.e. Standard Model particles)."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Glueball"
],
[]
] |
||
6qh9au
|
why aren't coal and oil interchangeable?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6qh9au/eli5_why_arent_coal_and_oil_interchangeable/
|
{
"a_id": [
"dkx8o4r"
],
"score": [
5
],
"text": [
"Coal can be converted into liquid fuel through a few different processes that are broadly called \"coal liquidation\". There are some plants that exist today that convert coal into things like jet fuel and the Nazi's used similar processes during WWII when they were cut off from oil supplies in Russia and the Middle East. The problem with is that the process is expensive and dirty."
]
}
|
[] |
[] |
[
[]
] |
||
4epg6b
|
Has there ever been a notable country to form without physical conflict/war?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4epg6b/has_there_ever_been_a_notable_country_to_form/
|
{
"a_id": [
"d22whc3"
],
"score": [
2
],
"text": [
"Sorry, we don't allow [\"trivia seeking\" questions](_URL_0_). These tend to produce threads which are collections of disjointed, partial responses, and not the in-depth discussions about a particular topic we're looking for. If you have a specific question about an historical event, period, or person, please feel free to re-compose your question and submit it again. Alternatively, questions of this type can be directed to more appropriate subreddits, such as /r/history /r/askhistory, or /r/tellmeafact. For further explanation of the rule, feel free to consult [this META thread](_URL_1_)."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/wiki/rules#wiki_no_.22trivia_seeking.22_questions",
"https://www.reddit.com/r/AskHistorians/comments/3nub87/rules_change_throughout_history_rule_is_replaced/"
]
] |
||
1dh9h2
|
space - time crystal
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1dh9h2/eli5_space_time_crystal/
|
{
"a_id": [
"c9q9tqp"
],
"score": [
6
],
"text": [
"I don't even..."
]
}
|
[] |
[] |
[
[]
] |
||
3g79lz
|
why are software installers (windows) used for programs that work fine as standalone executables?
|
I've recently been travelling a lot, and one thing that I've noticed is how many programs I use that work fine if you just copy the folder the executable lives in to a new computer or flash drive. Most of the time these programs are not installable from scratch without Windows administrator access. What's the rationale behind adding an extra layer of complexity, changing registry keys, and doing file access in global user locations when you could just distribute a copy of a compiled executable?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3g79lz/eli5_why_are_software_installers_windows_used_for/
|
{
"a_id": [
"ctvmqkn"
],
"score": [
2
],
"text": [
"Often times this is done for users who want uniformity in their apps. For a portable or self-contained application, often times the installers are just wrappers that add a Start menu entry, add registry keys so Windows knows that it is 'installed' and maybe things like user prefs.\n\nOther times, the installers also contain commom redistributal utilities such as VC++ or Direct X so that it will work if those utilities aren't previously installed."
]
}
|
[] |
[] |
[
[]
] |
|
3c6uhe
|
why do americans have to face the flag during the national anthem?
|
Never heard this one until a shower thought that was posted today.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3c6uhe/eli5why_do_americans_have_to_face_the_flag_during/
|
{
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"cssrh4q",
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],
"score": [
10,
8,
3
],
"text": [
"The flag represents our nation.\n\nThe national anthem is our \"nation's song\".\n\nFacing the flag (quietly and while rendering proper honors) when it is played is a matter of protocol, with the mindset that in doing so, you are showing respect, through the symbol, to our nation as a whole and also to all it represents and also to all those who have given parts or all of their lives in support of the nation.",
"We don't HAVE to, as in there's no compulsion to. That being said, social pressure makes it pretty much required in certain settings such as a sporting event. As someone else said it's pretty much about respect. ",
"Americans don't have to face the flag or even partake in the anthem. Facing the flag is tradition because it symbolizes the union."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
7ytwxb
|
why can't we increase our penis size through excercise, just like developing other parts of our body by working out?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7ytwxb/eli5_why_cant_we_increase_our_penis_size_through/
|
{
"a_id": [
"duj5g6j",
"duj5xn6"
],
"score": [
18,
2
],
"text": [
"Because working out increases the size of *muscles,* and this organ is not a muscle. So it's not relevant.",
"There are a couple of reasons why that doesn't work. First is that the penis isn't a muscle, rather it is full of spongy tissue which is inflated by blood to become firm. You can think of it like a water balloon with structure.\n\nWhen our bodies sense that our muscles are being worked in ways which are beyond their capabilities they are repaired in ways to make them better at the previous use. For example if you lift a large amount of weight all at once it will build one kind of muscle fiber, while if you are lifting a moderate weight many times it builds a different kind.\n\nThe key here is that it isn't just used frequently but in ways that push its capabilities. For example you can use your hands all day for normal tasks without making them stronger if you aren't doing anything they can't easily handle. For a penis it isn't clear how a signal of inadequacy would occur; how is the body supposed to know that the penis isn't doing its job just fine?"
]
}
|
[] |
[] |
[
[],
[]
] |
|
415wsq
|
I have heard a lot about the internment of Japanese-Americans during WWII, but how were Americans of German and Italian descent treated? Also, was it common for them to hide their German or Italian heritage?
|
[deleted]
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/415wsq/i_have_heard_a_lot_about_the_internment_of/
|
{
"a_id": [
"cyzvkky"
],
"score": [
4
],
"text": [
"At some point there was a movement to intern Italians who had never formally renounced their citizenship, regardless of how long they'd been in America. There were some arrests, mostly in California. Interestingly, Joe DiMaggio's parents were Italian citizens living in the US, and he raised a huge outcry. \n\nFrom the New England Historical Society site (_URL_1_): \n\nAttorney General Francis Biddle, in his book Brief Authority, described how he told Roosevelt about plans to intern enemy aliens.\n“And you're going to intern all of them?\" said the President in a tone that suggested he approved of the idea.\n\"Well, not quite,\" replied Biddle.\n\"I don't care about the Italians,\" continued Roosevelt. \"They are a lot of opera singers, but the Germans are different; they may be dangerous.\"\n\n\n\n\nAnd anecdotally, my grandma was a young Italian immigrant in Brooklyn during the war and remembers Italian-run stores putting up signs asking their Italian customers to exclusively speak English inside, or denouncing Mussolini. A lot of the very poor, Southern Italian community were initially strong supporters of Italian fascism and had to fight very strongly to prove their loyalty after the US entered the war. My grandmother and her family never tried to hide their heritage (it was way too obvious) but they were definitely pressured to overemphasize their patriotism.\n\nSome sources!:\n\n_URL_0_\n\n_URL_3_\n\n_URL_2_"
]
}
|
[] |
[] |
[
[
"http://articles.latimes.com/2010/aug/23/local/la-me-italians-20100823",
"http://www.newenglandhistoricalsociety.com/in-the-hidden-history-of-wwii-italian-enemy-aliens-were-interned-restricted/",
"http://www.sfgate.com/magazine/article/A-SECRET-HISTORY-The-harassment-of-Italians-2866287.php",
"http://www.archives.gov/research/immigration/enemy-aliens-overview.html"
]
] |
|
109myi
|
The Theory of Evolution explains the fact of evolution. What fact does String Theory explain and is it "just" a theory?
|
askscience
|
http://www.reddit.com/r/askscience/comments/109myi/the_theory_of_evolution_explains_the_fact_of/
|
{
"a_id": [
"c6bkdze",
"c6bl86q"
],
"score": [
3,
2
],
"text": [
"In physics there is a third use of the word \"theory\", meaning a mathematical framework that makes predictions, whether or not it has been verified. String theory is a vast framework which makes predictions, but so far none of the unambiguously new ones have been verified.",
"This question is basically just a by-product of an overly rigid use of wording.\n\nThe goal of string theory is to explain interactions between fundamental particles."
]
}
|
[] |
[] |
[
[],
[]
] |
||
3tn4ii
|
all these "free! just pay shipping!" items i keep seeing on facebook
|
I keep seeing a lot of cool shit, but it it seems like there must be a catch somewhere.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3tn4ii/eli5_all_these_free_just_pay_shipping_items_i/
|
{
"a_id": [
"cx7kgsq"
],
"score": [
3
],
"text": [
"If it is anything like I've been seeing on /r/NearlyFreebies and /r/free, most of those things most likely come from Chinese websites where they can buy in bulk for very little money (such as AliBaba/Express or Wish/Geek, where many things are $1 with free shipping) and then they charge high rates of shipping. A quick reverse image search can usually link you to the original item on the Chinese site."
]
}
|
[] |
[] |
[
[]
] |
|
382rra
|
on computers running windows, how can an empty folder take up 0 bytes? surely the disk has some trace of the folder there, even if there's nothing in it?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/382rra/eli5_on_computers_running_windows_how_can_an/
|
{
"a_id": [
"crrshnk"
],
"score": [
15
],
"text": [
"Part of the reason you buy a 60GB hard drive and don't get the full 60GB is that some of that space is sectioned off for information that manages the file system. The space for file system information is fixed, and you can't store things in it. The folder would be an entry in the file system data, and not be present on the part of the disk where things are stored.\n\nIt's like a card catalog in a library. Adding cards to the catalog does not take up space on the shelf; only in the drawer with the cards."
]
}
|
[] |
[] |
[
[]
] |
||
1x8em5
|
Why do actors in modern movies today feel more "real" than the acting we see in old movies like Casablanca?
|
Is the difference in technique, culture, medium, or something else?
I've heard of "method acting" where actors almost immerse in and become their role--was this less common before? If the difference is cultural, does that mean that normal people actually walked and talked like the people in old movies? Did the shift from the theater stage to TV and movie screens play a role? A mix of causes? Or am I way off base and is there some other reason entirely?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1x8em5/why_do_actors_in_modern_movies_today_feel_more/
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"Others have covered the technological and practical aspects, but the difference in acting styles that you are noticing is partly the influence of [Constantin Stanislavski](_URL_12_)'s System that he developed between 1911 and 1938.\n\nThe System (or sometimes \"The Method\") was based on the idea that human beings are not consciously in control of their emotions and cannot simply summon emotive inspiration on command. One could, however, *coax* or *entice* the desired emotions.\n\nAt first Stanislavsky included what actors call Emotional Memory (based on French psychologist [Theodule Ribot's](_URL_4_) concept of 'Affective Memory') wherein an actor utilizes memories of his own past experiences to emulate the emotional life of his character. Emotional Memory became a controversial method after [Michael Chekhov](_URL_6_), one of Stanislavski's protégés, suffered a nervous breakdown. Although Stanislavski shied away from Emotional Memory exercises in his later years, they remain a common (if somewhat controversial) staple of actor training in the Western World. Later, The System was expanded to include the study of physical actions, gesture, verbal/physical communication, and the nature of the Given Circumstances to evoke the actor's own natural emotions for a performance on stage.\n\nStanislavski believed that if an actor completed all of the necessary steps of The System, the desired emotional state would be produced within the actor and the audience would perceive his/her actions as genuine and truthful.\n\nThese ideas began to migrate to the United States in the 1920s where they flourished and were further developed and adapted by American artists like [Lee Strasberg](_URL_9_), [Sanford Meisner](_URL_10_), and [Stella Adler](_URL_0_).\n\nActors employing these methods began to appear in major screen roles in the late 1930s, but the new, naturalistic style really began to take over in the 1950s-1960s after the success of films like [A Streetcar Named Desire](_URL_7_). Today, The System and its countless derivatives are so common in actor training that they have almost replaced the older, more representational acting styles completely.\n\nThis is only a bare-bones summary of a huge topic. For further reading:\n\n[*An Actor Prepares*](_URL_8_), [*Building a Character*](_URL_5_), and [*Creating a Role*](_URL_11_), by Constantin Stanislavski.\n\n[*A Dream of Passion: The Development of the Method*](_URL_2_), by Lee Strasberg\n\n[*On Acting*](_URL_1_), by Sanford Meisner\n\n[*The Art of Acting*](_URL_3_), by Stella Adler\n\n",
"A little of column A and a little of column B.\n\nFirst, technique – Film acting at least partially takes place on the editing room. The audience will tend to impress emotions and thoughts on actors depending on the visual context of the shot; this was documented as early as the 1910s, when Russian film-makers, critics and theorists such as Lev Kuleshov started experimenting with montage to construct meaning in film. The same shot of an actor's face would be interpreted differently by the audience depending on what it was cut with – the same expression, alongside a bowl of soup, a casket, or a woman, would indicate hunger, sadness, or lust respectively.\n\nThese ideas eventually seeped into film-making all over the world. In Hollywood, European vanguard ideas about film were mainly introduced in two ‘waves,’ the first one being mainly German expatriates who came to America to work on film after the vibrant, experimental vanguard cinema of the Weimar republic collapsed. The second were American film-makers who came into the industry in the sixties and seventies, who had a very different perspective and background from their predecessors; unlike the old guard, they had not only grown up with movies but studied film in an university environment, and were very acquainted with the work of European cinema throughout history as well as the writings of film theorists of the era.\n\nThe use of montage and photography to communicate the internal states of characters on screen naturally lends itself to a more subdued style of acting, as the actor is doing less of the work of communicating the character's processes to the audience. If you look at a modern-day prestige drama, especially something on television such as (Say) *Mad Men,* the so-called ‘Kuleshov Effect’ is doing a lot of the heavy lifting of exposing the characters' emotions to the audience.\n\nIn early film, the absence of sound and the preponderance of full-body shots made ‘acting with your whole body’ the norm, and the style of acting that goes with that stuck around after the development of close-up shots (Gradually over the 1910s and 20s) and synchronised audio (Late 1920s and 30s). \n\nIt is also true, of course, that the experiences of film-makers outside Hollywood shows that there's no natural or inherent connection between silent film and a ‘histrionic’ style of acting; I feel like the acting style in early Hollywood film is better explained by cultural factors rather than technical limitations of the medium. But speaking of which...\n\nCultural factors: The very first generation of actors in Hollywood came largely from vaudeville and other forms of popular theatre. They would have been most acquainted with broad comedy and melodrama, genres that aren't exactly known for their restrained performances; and since early narrative film targeted the same audience as vaudeville, those actors, and the style and training they had, were a good fit.\n\nAs cinema struggled to gain cultural validation in America and sell itself to middle- and upper-class audiences, film actors increasingly came from a more classical theatre background. This is the mannered, representational performances you see in Classic Hollywood Cinema. It's associated with the (artificial) ‘midatlantic’ English dialect, clarity of enunciation, and a more formal (As in *formalism,* not *formality*) approach to acting.\n\nMeanwhile, of course, a cultural revolution was taking place in theatre; the Stanislavski method, developed by Russian theatre actor and director Constantin Stanislavski over the course of the 1910s and 20s. The Method, often called ‘method acting’ does (For some practitioners) involve staying in character for long periods of time, but originally it focused on the idea of the ‘emotional memory,’ using the actor's real memories of his life experiences to build a character. Later, Stanislavski would focus on the study and reproduction of physical actions. This method would eventually not only be brought to America (It is most famously taught at the Actors Studio in New York) but also largely supplant the more mannered classical style. This shift can be seen in later Classical films, starting *A Streetcar Named Desire* – Directed by Actors Studio founder Elia Kazan. By the time the classical era ended, the method had cemented itself in Hollywood.",
"Casablanca actually serves as an interesting example since it's something of a mix of different styles/eras of film. The director Michael Curtiz made his first film in 1912 and worked all the way up to the 60s. Bogart and Bergman both came from stage backgrounds. Conrad Veidt appeared in a number of major German films in the 20s before wisely emigrating to England in 1933 and while Peter Lorre's career got started quite a bit later he put together a masterful performance in *M* in 1931.\n\nSo we're dealing with at least three very different approaches to acting and filmmaking. A stage background like Bogart and Bergman had wasn't at all unusual. If you watch some [very](_URL_3_) [old](_URL_8_) silent films you'll see that the acting style is incredibly melodramatic and today almost comically stagey. The vast majority of actors in the early silent period came from the stage and still relied very heavily on body language to convey emotion. Today, this is also exacerbated by filming and projection speed. The silent film period didn't have a true standard filming and projection speed like we do today as [Kevin Brownlow notes.](_URL_4_) (Hopefully this link is okay, it seems the original page his article was on is down) *Typically* it was around 16 FPS, although it could vary quite a bit depending on director or projector. When a film that was shot at 15/16/17 FPS is projected at today's speed of 24 FPS movement becomes jerky and visibly looks off.\n\nFortunately, directors and actors figured out fairly quickly that the incredibly stage-based style of acting worked against what film could do. There are a number of different people you can point to, but the most prominent were D.W. Griffith and Lillian Gish. Gish's [acting](_URL_1_) [style](_URL_6_) is still far from naturalistic by today's standards but it's a huge leap forward in terms of how well she's using her face and more reserved body language to express herself. Griffith also made frequent use of close-ups in his films which you can also pick up from those two clips. Jump forward about a decade in America and you'll see that acting has become [more](_URL_0_) [sophisticated](_URL_7_) but it's still distinctly old fashioned. By the early 30s sound film is becoming predominant and acting styles can take another big leap forward. If you take a director like, say, Ernst Lubitsch who was already masterful at using and directing actors and give him sound he can do some [wonderful](_URL_10_) things. Acting overseas was of the same sort of quality as you can see in a film like [M](_URL_2_) or [The Passion of Joan of Arc](_URL_9_). If we go back to Vedit for just a second though, you'll see a far more [impressionistic](_URL_5_) and decidedly non-natural style of acting. Germany's film culture/history in the 20s and 30s is another huge topic though and I'm afraid I've gone on at length enough.\n\nI hope I've provided a somewhat different perspective on the differences in acting style. If you look at it purely from film history in the 30s and 40s you get actors and directors in Hollywood from all sorts of different backgrounds. At the time you easily could've seen a Hollywood film directed by a German that starred a Swede. Hollywood had an absolutely rapacious appetite for talent and once Hitler came to power in 1933 it gladly sheltered all the German talent it hadn't already lured away. Theatre's influence on film still hasn't completely vanished. Plenty of actors get their start on the stage to this day and the same was certainly true 60+ years ago. Acting style has been developing this whole time as well and technological developments (particularly the introduction of sound) have had an enormous influence on how actors act in film. When you throw in the incredibly varied cultural and artistic backgrounds artists in Hollywood had at the time you're practically bound to get vestiges of all sorts of different eras of film and theatre popping up.",
"as a sidenote, it might be worth noting that modern acting, while more realistic than acting from older generations, isnt aimed so much at realism as it is selling the story. we can see this by comparing real life footage with scenes from cinema. real life is often much more awkward, stilted, less dramatic, and more ambiguous. a very obvious example of this is choreographed fight scenes vs. actual street fights. but this is true even for dramatic scenes of dialogue.\n\nso both older generations and newer ones are attempting to tell a story in their acting. the difference is, over time audiences have developed a taste for increasingly realistic story telling. thus contemporary actors often deliver more realistic performances.",
"I'm not a historian, but studied theatre and film in college. I think technological changes have a lot to do with it, but acting style as well. There's a semi-famous story of Sir Lawrence Olivier (a classically trained actor) during the filming of Marathon Man. He saw Dustin Hoffman (a practitioner of Method) preparing for an upcoming scene where he was supposed to be very excited, amped up, etc... by running around and hitting a punching bag, that type of thing. Olivier asked him what he was doing, and after Hoffman explained it Olivier replied \"my dear boy, have you tried acting?\" Its important to note that this story may be entirely apocryphal, but it fits with both men's acting styles and personalities. \n\nI think the adoption of Method has little to do with the change in perception of old films, but WHEN it was adopted is the major demarcation point. Prior to the widespread use of Method (and other newer forms of character building for actors in film specifically) almost all actors were trained classically, that is for stage acting. In stage acting you're trained to speak with a non-accent (often called a mid-atlantic accent) to be more easily understood by a theatre audience. Also to speak from chest (as opposed to speaking from the back of the throat or from the mouth which are more natural) as it caused greater vocal projection. And finally classical training taught actors to enunciate every word crisply and clearly, again to aid in being understood by the audience. None of these techniques were needed by film actors, as microphones picked up sounds at far lower levels than a dude sitting in the 50th row of the balcony at a theatre. Because of this, old film actors seem to be speaking in a way that is totally unnatural and forced, which is a big part of why those films seem less realistic to us today. You can see that is less about the adoption of Method because a chabge to any acting style more geared toward normal speech (and body movements, as classically trained actors moved differently as well) would produce the same demarcation point. ",
"I have a related question.\n\nVintage videos from the 20s and 30s seem like they are fast-forwarded. Charlie Chaplin's films are good examples. Why is that?",
"Most of the answers here seems to focus in American cinema and the advent of method acting. A similar thing happened in Europe, to exemplify, I've use Dreyer and Bresson. Party because they thematicly made very similar films, partly because they both filmed jeanne d'arc. Bresson had a very strong feeling that cinema was not theatre. That all influence would be bad as it would (as in Hollywood) dilude the artform (film). In his book notes on cinematographie he discusses how to create reality. Most famously he calls his actors models, unlike the method actors he forces them not to act. The timeframe is about the same as Brando in the US, Perhaps a few years earlier. Unfortunely im not knowledgable enough about later cinema to spak about how it affected godard, Resnais and others in the new wave. I have read interviews in andre bazins film magazine written by them that makes it highly likely that the more natural acting took another route in Western Europe. \n\nI can find sources in 10 m",
"For me, the most interesting document pertaining to this question is Elia Kazan's *A Streetcar Named Desire* from 1951. This was a film that recognized the distinction between the older style of acting and the new style based on \"method acting,\" and found an ingenious way to use both styles by deliberately contrasting them to make a point about the older, rural South and the rising urban culture. Anybody interested in this question should be sure to watch *A Streetcar Named Desire.*\n\nVivien Leigh, most famous for her role as Scarlett in *Gone with the Wind,* represents the old-school, theatrical acting style. Marlon Brando represents the new \"realistic\" or naturalistic style based on \"method.\" His portrayal of Stanley Kowalski here was an explosive cinematic debut and made him an instant star and the acting ideal for generations of young male actors to follow. You've witnessed the influence of Brando when you've watched Al Pacino, Robert DeNiro, James Dean, Sean Penn, Jack Nicholson, Ryan Gosling, or Christian Bale. These are just some of the actors who eagerly acknowledge Brando's influence.\n\nThe two styles are so different that they normally wouldn't have worked well together in the same movie. Brando's naturalistic acting highlights the staged, affected qualities of Leigh's performance.\n\nBut the contrast serves a purpose in the film, because Leigh's character, Blanche Dubois, represents an older, more refined and affected (and ultimately false) way of being. Stanley Kuwolski represents a more raw, direct, unrefined, immediate way of being. Tennessee Williams' play, upon which the movie is based, is interested in looking at these two ways of being and contrasting them, showing how one is replacing the other, acknowledging how this new way is more \"real\" and maybe more \"natural,\" but asking also if it is more brutal and ugly, and asking us to question this transition from an elaborately staged way of life to one more direct and unaffected.\n\nFor these purposes, the two contrasting styles work beautifully, and Leigh and Brando add their own particular dimension to the themes of the play.\n\nOn top of that (or underneath that?) the movie makes a fascinating meta-statement about the changing nature of movie acting, providing an effective and informative illustration of the distinction the original poster recognized and questioned.",
"Reading through the comments and answers I am struck by something that doesn't seem to appear at all; the fact that the films are a product of the age itself. What I mean is that accents, cultural touchstones, slang terms, the aesthetics of the time - what is an 'attractive' man or woman, what voices or cadences are considered attractive or 'sexy' - as well as what was expected of films in that period all play a factor. Method or not, frame rate or not, if a film didn't adhere to the aesthetic of the time then it did not do well, period. \n\nThis can also be explored in pictures, or even letter writing, to some degree. Why doesn't anyone smile in old pictures - the myth that old pictures took 20 minutes or so persists in my history classes and yet it is not completely true. By the end of the 19th century, photos were relatively instantaneous and yet few still smiled. Why? were people much more grim back then? Did they 'invent' smiling some time in the 20th century? No, it was expected of people - adults and children alike - to be somber for posterity and smiling was inappropriate for the medium. Furthermore, what about certain slang words - things like 'confab' or 'chewing the fat' or 'cut the mustard' or 'the bee's knees'- just don't have the contemporary meaning or usage that they used to; they sound archaic. Modern watchers who hear such things are instantly taken out of the narrative and reminded that they're watching an old film, thus making the acting seem a little 'worse' for lack of a better term.\n\njust my two cents.",
"I haven't seen it mentioned here, but naturalistic acting was in fact doing just fine in the 1900s (around the switch from one reels to 2+) to 1920s, just prior to the advent of sound. \"The Passion of Joan of Arc\" which was discovered well after its filming is a masterpiece of silent, no makeup, intense closeups, the works. \n\nSound is the mechanism that essentially destroyed and rebuilt the industry and had to resort (due to the then bulky, loud machines) to medium/wide shots of people, who were in fact shouting to be heard, and often at a framerate that makes them seem hyper. His Girl Friday, pristine example of that era. It's not a beautiful looking or slow emoting type of movie, for reasons listed above it nearly can't be, its straight from vaudeville as others have pointed out - but it's snappy, witty and works. And had to, for about 25 years. \n\n*For even earlier techniques, Hitch's Sabotage and the 1919 Scarface have no running sound or score, but punctuated intervals of separately recorded dialogue. You kept the intensity of the performance in the faces, in this manner, but the eerie silence sucked rocks and the writing was on the wall. \"You ain't heard nothin' yet,\" indeed. \n\nBut the culture of the slow-movement, 'humanist' driven works popped back up after the recorders got smaller, boom mikes got invented, and the aforementioned acting revolutions. \n"
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[
"http://en.wikipedia.org/wiki/Stella_Adler",
"http://books.google.com/books?id=doy-aorlNagC&printsec=frontcover&dq=sanford+meisner+on+acting&hl=en&sa=X&ei=gVX0UrXcIqSRygGn9ICYBw&ved=0CDcQ6wEwAA#v=onepage&q=sanford%20meisner%20on%20acting&f=false",
"http://books.google.com/books?id=CMqaQgAACAAJ&dq=a+dream+of+passion&hl=en&sa=X&ei=g1T0Uqb6FsqMyQGn-YDoCw&ved=0CCsQ6AEwAA",
"http://books.google.com/books?id=i6rE7ocYWngC&printsec=frontcover&dq=the+art+of+acting+adler&hl=en&sa=X&ei=06_0UufDC4ifyQH-oYDYAg&ved=0CDcQ6wEwAA#v=onepage&q=the%20art%20of%20acting%20adler&f=false",
"http://en.wikipedia.org/wiki/Th%C3%A9odule-Armand_Ribot",
"http://books.google.com/books?id=3T9MAQAAQBAJ&printsec=frontcover&dq=building+a+character+stanislavski&hl=en&sa=X&ei=PVX0UpHCNJDiyAGL6oHABQ&ved=0CCwQ6wEwAA#v=onepage&q=building%20a%20character%20stanislavski&f=false",
"http://en.wikipedia.org/wiki/Michael_Chekhov",
"http://www.imdb.com/title/tt0044081/?ref_=fn_al_tt_4",
"http://books.google.com/books?id=MUtMAQAAQBAJ&printsec=frontcover&dq=an+actor+prepares&hl=en&sa=X&ei=WVT0UuX1BsqCyQGQgoGAAw&ved=0CCwQ6wEwAA#v=onepage&q=an%20actor%20prepares&f=false",
"http://en.wikipedia.org/wiki/Lee_Strasberg",
"http://en.wikipedia.org/wiki/Sanford_Meisner",
"http://books.google.com/books?id=kLzF5Ojw8MwC&pg=PR13&dq=creating+a+role+stanislavski&hl=en&sa=X&ei=AFX0UpfXJ6mCygGz3oHQAg&ved=0CCoQ6wEwAA#v=onepage&q=creating%20a%20role%20stanislavski&f=false",
"http://en.wikipedia.org/wiki/Constantin_Stanislavski"
],
[],
[
"http://www.youtube.com/watch?v=-XYZQbjGykA",
"http://www.youtube.com/watch?v=pp4f9aYAJZE",
"http://www.youtube.com/watch?v=jUDUbxsNjV0",
"http://www.youtube.com/watch?v=8oTdPklBE0Y",
"http://www.thephora.net/forum/showthread.php?t=68065",
"http://www.youtube.com/watch?v=UEEOEnAmGl8",
"http://www.youtube.com/watch?v=KpQNpUCM7U4",
"http://www.youtube.com/watch?v=QiXkFveWkMA",
"http://www.youtube.com/watch?v=_FrdVdKlxUk",
"http://www.youtube.com/watch?v=BC3IoY-gXzQ",
"http://www.youtube.com/watch?v=CJz-PtYzkUY"
],
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cl2z8g
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Why are solar sails reflective? Wouldn't the momentum transfer from the photons to the sail better if it were matte?
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Maybe I don't understand momentum properly, but wouldn't the direction of the momentum be better conserved if the photons didn't bounce off the surface?
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askscience
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https://www.reddit.com/r/askscience/comments/cl2z8g/why_are_solar_sails_reflective_wouldnt_the/
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"Consider 2 scenarios: The first is a sail that is completely non-reflective and the second is a sail that is perfectly reflective. Now consider a photon with momentum *p* striking the sail from a direction perpendicular to the sail.\n\nIn scenario 1, the full momentum *p* is transferred to the sail. The photon is absorbed and ceases to exist and the spacecraft now has an increase in momentum of *p* in the direction that the photon was traveling.\n\nIn scenario 2, the photon is reflected and will travel back in the same direction that it came from. It had momentum *p*, so after reflection it'll have momentum *-p*. The photon lost 2*p* worth of momentum, so because of conservation of momentum, we know that the spacecraft gained 2*p* worth of momentum in this exchange.\n\nClearly, by reflecting the photon, the amount of momentum transferred is double what it would've been had the photon been absorbed.\n\nIf the photon doesn't travel on a path perpendicular to the sail, but instead strikes it at an angle, the result is the same. In this case, you can split the momentum of the photon into two components: the momentum perpendicular to the sail and the momentum parallel to the sail. If the photon is absorbed, the space craft gains both components of the momentum, but nothing more.\n\nBut if the photon is reflected, the outgoing photon will have both components of its momentum flipped, making the change in momentum for each component twice the original magnitude of that component. And that difference is gained by the space craft. Again, the effect of perfect reflection is twice that of perfect absorption."
]
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2uh08l
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how do you pause a video game, as in what is going on with the processor and memory once a pause is executed?
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For me, pausing a single player game began as simply as pressing "start" on an NES controller. ELI5 how the system accepts the pause command, and continues exactly where I left off once the resume command is requested.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2uh08l/eli5_how_do_you_pause_a_video_game_as_in_what_is/
|
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"In most games, the program is performing some sort of loop: check button presses, move characters, move enemies, etc. and repeat. When you hit pause, it just skips all the other steps besides checking button presses. So when it sees that you've hit pause again, it can keep moving as it did before.",
"How would you pause something you were doing? You'd just stop doing it.\n\nComputers can idle, they don't have to be doing anything at a given time. Most CPUs even have a command that literally means 'do nothing for one clock cycle'.\n\nIf you want to pause a game just suspend any activities that affect game state. No physics, no movement, no inventory additions or subtractions, etc. Just wait for the un-pause to resume the game from the state it was pause in. "
]
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26zwt8
|
In ancient battle, what was the casualty ratio of combat to rout?
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I'm currently reading "How Great Generals Win" by Bevin Alexander (great book, recommended by someone on this sub). Towards the end of the chapter about Hannibal and Scipio, Alexander states that in encounters of ancient armies, by *far* the most casualties occurred not during the actual fighting, i.e. exchange of missiles, projectiles, direct confrontation of infantry or cavalry charge, but instead as a result of unorganized retreat and the routing by enemy cavalry.
The confrontation after which he makes this observation is the Battle of Zama, which constitutes the end of the Second Punic War. He explains the battle was in terms of infantry more or less even - while the Roman drives the Carthaginian cavalry of the field - and attributes the massive differences in loss of lives, around 20-30k of the Carthaginian army opposed to 2-3k on the Roman side, to the aftermath of the battle, that is the slaughter of the fleeing troops by the Roman cavalry.
Now, I understand Hannibal had a number of less well trained soldiers, which were overpowered, and thus make a fairly large contribution to his high death rate. However the question I'm trying to arrive at is, were the deaths in ancient (hand-to-hand) combat indeed not quite as numerous as commonly believed/pictured; and what would be a realistic assumption of the ratio of casualties during and after battle?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/26zwt8/in_ancient_battle_what_was_the_casualty_ratio_of/
|
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"Throughout ancient times, casualty rates for the loser of pitched battles were significantly higher than those of the winner. The losing side having 5 to 10 times the casualties of the winning side would not be uncommon. At Cannae, a battle which was especially bloody, Carthaginian losses numbered 6000 to 8000 (12 to 16% of the army), whereas the Romans suffered about 50k deaths (60% of their army). \n\nThe difference in casualty rate is almost entirely due to the aftermath of the battle. To flee from the battle, combattants literally had to turn their back to the enemy. Exposing your back is never a good idea, but it also reduced the effectiveness of the fighting formation of the army. Much of the protection a soldier had was from being in pretty tight formation with other soldiers at his side and right behind him. Turning tail would reduce the pressure on the enemy and might leave gaps in the formation. Furthermore, in order to run faster fleeing soldiers would often drop their heavy shields, reducing whatever protection they had left even further. \n\nJohn Lazenby mentions in his article *The Killing Zone* that fugitives might even trample each other in their desperation to get away. Most casualties will have been inflicted by a pursuing enemy though. A fleeing army could easily be run down by cavalry, or parts of the now mostly defenseless army might be surrounded by light infantry and massacred. Wounded enemies left on the battlefield would be killed. Overall, the winning army would suffer only few additional losses in the process of pursuit and mopping up.\n\nThe answer to your question then is perhaps more simple than you thought. The casualty ratio of combat to rout is approximately the difference between the casualties of the winner and the casualties of the loser. The winning army will have suffered nearly all of its losses in the actual combat. The losing army will have suffered about that (perhaps slightly more, they were losing after all) in the actual combat and the rest afterwards.\n\n---------\n\nSources:\n\n* A. Goldsworthy, *Cannae* (London 2001)\n* J. Lazenby, *The Killing Zone*, in: V.D. Hanson, *Hoplites: The Classical Greek Battle Experience* (London 1991), p. 97-109\n"
]
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51v8a2
|
Can something be 1.5 plank lengths long?
|
Nothing can be shorter than a plank length, but is length/distance a discrete thing?
|
askscience
|
https://www.reddit.com/r/askscience/comments/51v8a2/can_something_be_15_plank_lengths_long/
|
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"text": [
"[The Planck length is not a fundamental pixel size](_URL_0_). It's just a really small length-scale constructed from physical constants, and interactions at that scale require an understanding of quantum gravity.",
"It's actually not true - as far as we know - that nothing can be shorter than a Planck length, and nor is it true - again, as far as we know - that length (or, for that matter, time) is discrete.\n\nI'm careful to add \"as far as we know\" because we really don't know much about what happens at the Planck scale. In fact, the Planck length (and similarly the Planck time, Planck mass, etc.) is best defined not as the minimum distance, but as the distance *where our understanding of physics completely breaks down*.\n\nThe Planck units are constructed by multiplying different factors of three fundamental constants - the gravitational constant, Planck's constant, and the speed of light. The first one tells you how strong gravity is, and the second tells you how important quantum mechanics is. So we can think the Planck scale as the place (the distance, the mass, etc.) where we need to understand both gravity and quantum mechanics.\n\nThe trouble is that we actually don't know how to reconcile gravity and quantum mechanics. The best theory we have of gravity - Einstein's general relativity - isn't fully compatible with quantum physics. The theory itself tells us that it stops working around the Planck scale, and that we need to replace it with a different, more fundamental theory around that point.\n\nWhatever that theory of *quantum gravity* is will answer all these questions about what, if anything, the Planck length really means - whether it's a minimum length, whether space is discrete, or whether something else entirely different happens."
]
}
|
[] |
[] |
[
[
"https://www.physicsforums.com/insights/hand-wavy-discussion-planck-length/"
],
[]
] |
|
2xd3l4
|
Can you think of a culture that existed 1000 years ago, anywhere on the planet, where people (at least most people) didn't believe in corporal punishment as an element of good parenting?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2xd3l4/can_you_think_of_a_culture_that_existed_1000/
|
{
"a_id": [
"cozfawc",
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37,
9
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"text": [
"The best I can do is point at the San people, who are hunter gatherers in the southwest of Africa. Their culture has likely persisted in the same location from the Paleolithic era, because it's so inhospitable there they wouldn't have many people trying to take from them their lands. Their childrearing philosophy is notable for its leniency towards children. \"Children have no sense\" is the most commonly applied aphorism, and children generally aren't the subjects of corporal punishment. \n\nThis is from college classes, but here's a source that basically backs up what I'm saying._URL_0_",
"There were numerous peoples amongst the Native Americans that regarded corporal punishment as a rather obsolete form of parenting, instead allowing more peaceful or inductive forms of punishment. The methods utilized by various cultures amongst the Native Americans included: an apology to each family member, shame and dishonour, ignoring the child for a period of time, and teaching the child the impact of their behaviour on others (typically the wider community). \n\n[*Parenting Characteristics in Native American Families*, pp. 32-33](_URL_0_)"
]
}
|
[] |
[] |
[
[
"http://www.context.org/iclib/ic04/mcelroy/"
],
[
"https://shareok.org/bitstream/handle/11244/9450/Newcomb_okstate_0664M_1649.pdf?sequence=1"
]
] |
||
343ain
|
why do guys shave when they are in the military and in space?
|
I don't even want to shave and I'm at home! hehehe
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/343ain/eli5why_do_guys_shave_when_they_are_in_the/
|
{
"a_id": [
"cqqu4rx"
],
"score": [
5
],
"text": [
"Per regulation. \nAir Force is AFI 36-2903. \nIt gives the appearance of uniformity and professionalism. \nAlso, in case of a CBRN attack, if you're shaven, when you have the gas mask on, it creates a better seal to your face. So you don't get fucked up and shit. "
]
}
|
[] |
[] |
[
[]
] |
|
8282o8
|
Is wild cattle in the US extinct and are owned cattle domesticated at this point?
|
I realized that my many years on Earth I have never seen a wild cow or cows just chillin in the wild. This lead me to wonder if we stopped eating beef and drinking milk, would cattle soon disappear in the US. I know in countries like India, there are Cows in the wild, but in the US it doesn't seem like there are any left.
In such a case, would these cattle be considered domesticated since they have had years of contact with humans and exhibit in many cases traits that would consider them a domestic animal?
|
askscience
|
https://www.reddit.com/r/askscience/comments/8282o8/is_wild_cattle_in_the_us_extinct_and_are_owned/
|
{
"a_id": [
"dv83tlx",
"dv865vx"
],
"score": [
11,
7
],
"text": [
"Cattle originated in Asia and Europe. They are not native to the Americas. There are no such thing as wild cattle here, however there may be a few feral ones. Most cattle here are owned. They might be released on public grazing lands but they are still owned.\n\nBison are bovines which are \"wild\" in some areas, but not as free roaming as they used to be and really only exist in parks, not like deer which can pretty much go wherever the want.",
"Wild cows - called aurochs - have been extinct since the 17th century, and were very rare for quite a while before that. They were native mostly to the Eurasian steppes and forest, although a subspecies was also found in India.\n\nNote here that aurochs aren't cows; domestication was so long ago, that cows became a different species, so in a sense, there never were wild cows. \n\nThere are, and have been, feral cows around the world: populations of cows which escaped or were abandoned by ranchers, and live on their own in the wild. They're fairly few in number, though, and you wouldn't likely come across them on your own. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
17azbn
|
how does a black hole have mass?
|
I was asked this last night by my stepmom. I didn't have a satisfactory answer.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/17azbn/eli5_how_does_a_black_hole_have_mass/
|
{
"a_id": [
"c83unpj"
],
"score": [
2
],
"text": [
"A black hole is often created by star collapsing much of its mass into a small space. It's literally a lot of mass in a small volume. You might as well ask how an apple has mass. "
]
}
|
[] |
[] |
[
[]
] |
|
14sz82
|
If a "flood of dopamine" causes downregulation of dopamine receptors, what causes upregulation?
|
The obvious answer is that a lack of dopamine over time would cause the neurons to upregulate their dopamine receptors; what I want to know is whether that is actually the case or if upregulation is caused by some other trigger (or if not enough is known about the process to say one way or the other).
|
askscience
|
http://www.reddit.com/r/askscience/comments/14sz82/if_a_flood_of_dopamine_causes_downregulation_of/
|
{
"a_id": [
"c7g7pfy"
],
"score": [
5
],
"text": [
"Lack of dopamine does up-regulate the receptors, but some studies also show that activation of the NMDA glutamate receptor results in dopamine receptor up-regulation as well. (_URL_0_)\n\nIn an older study, hypertensive rats were found to have a higher density of dopamine receptors as compared to the control group. This points to another mechanism for up-regulation that is related to hypertension, but I believe is is not yet understood. (_URL_1_)"
]
}
|
[] |
[] |
[
[
"http://www.ncbi.nlm.nih.gov/pubmed/11818555",
"http://www.ncbi.nlm.nih.gov/pubmed/8433803"
]
] |
|
1nemqw
|
Was the United States' approach to the Philippine Theater of the Spanish-American War exceptional for any reason?
|
I'm asking specifically in terms of imperialism. Americans have historically been reluctant to admit to being imperialists, but it seems to me that the treatment of the Philippines bears out the argument that the US was engaging in formal imperialism. Was there anything present in this conflict that separated the US from the European imperial powers of the day?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1nemqw/was_the_united_states_approach_to_the_philippine/
|
{
"a_id": [
"cci27pp"
],
"score": [
6
],
"text": [
"The initial U.S. engagement in the Philippines was made as a calculated attack on the holdings of the Spanish elsewhere in the world. From the outset, the conflict was not meant to be an occupation, but a weakening attack upon their navy and imperial holdings. However it devolved into a prolonged occupation for a variety of logistical, political, and social reasons. \n\nTo underscore how completely unprepared the U.S. was for the Philippines, the Navy had to purchase barges from private Californian shippers and fishers, then retrofit them for troop transport, and send them off. The voyage was so long and the living quarters so despicable that morale had already plummeted by the time they arrived. Commodore Dewey wasn't *supposed* to take Manilla, just beat the Spanish fleet. But he insisted and requested ground forces to complete the American Victory. Meanwhile, the bulk of the U.S. attention was directed squarely at Cuba, and troops, as well as supplies, were mobilizing *east* not *west.* \n\nSo in the month and a half between the determination on who sunk the *Maine,* the army had to drastically re-align its priorities, and relocate its assets, to factor in an occupation of Manilla. The whole debacle with Aguinaldo, who was [supposedly] promised a seat at the table with American Negotiators upon his return from exile further complicated matters, as different people were operating under different assumptions about *who* exactly was in power, and calling the shots. High turnover rates in U.S. generals and communication shortfalls between the Army and the Navy exacerbated the crisis, and escalated the conflict.\n\nSource: I wrote an article on the newspaper coverage of the conflict, and am subsequently versed in the History and historiography. I can get some specific books for you to check out when I get to my office tomorrow."
]
}
|
[] |
[] |
[
[]
] |
|
rbhe1
|
Are there any salt water rivers?
|
I was wondering why the oceans are salt water, and even some lakes but there are no salt water rivers? Do they exist? When rivers form from the ocean (I think this happens), how quickly do they lose their salt?
Edit: Thanks for the great responses. Life makes slightly more sense now :)
|
askscience
|
http://www.reddit.com/r/askscience/comments/rbhe1/are_there_any_salt_water_rivers/
|
{
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"c44ink7"
],
"score": [
13,
5,
2,
7
],
"text": [
" > I was wondering why the oceans are salt water, and even some lakes but there are no salt water rivers?\n\nThe answer has to do with how salt and water get together. When an ocean forms over very long time periods, the salts carried away from the land by rivers concentrate over time in the ocean, gradually building up the salt content of the water.\n\nBut the water on the land comes (mostly) from water that evaporated over the oceans and then fell as rain over the land, but the process of evaporation carries away only water, not salt.\n\nSo a river's water might have a small amount of salt resulting from the water's tendency to absorb material from the land it crosses, but the oceans have a much higher salt percentage, because over time they concentrate the salts that are deposited there by rivers.\n",
" > When rivers form from the ocean..\n\nThey do not.",
" > When rivers form from the ocean... \n\nRivers carry water back from land (which is at higher altitude than sea level) after it has evaporated from the ocean and been deposited as precipitation over land. There's some brackish (mixed salt and fresh) water near the mouths of rivers where there may be wetlands as well.",
"Kind of. Depends on whether it can qualify as a \"river\".\n\nThe bay of [Garabogazköl](_URL_1_) is connected to Caspian Sea by a narrow 6.5 km straight. Because it's surrounded by a desert, the Garabogazköl evaporates water faster than the Caspian Sea, causing the water level in the bay to be lower than in the sea. This causes the straight to have a strong permanent one-way current towards the bay. In fact, on [Google Maps](_URL_0_) the straight looks a lot like a river, with visible traces of a delta and even [oxbow lakes](_URL_2_).\n"
]
}
|
[] |
[] |
[
[],
[],
[],
[
"http://maps.google.ca/?ll=41.076763,52.927666&spn=0.104299,0.148487&t=h&z=13",
"http://en.wikipedia.org/wiki/Garabogazk%C3%B6l",
"http://en.wikipedia.org/wiki/Oxbow_lake"
]
] |
|
7n2kq0
|
if the ice caps melted, would the oceans be colder or warmer?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7n2kq0/eli5_if_the_ice_caps_melted_would_the_oceans_be/
|
{
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"drykbyb",
"dryklkc",
"dryli5z",
"dryll7k",
"dryne6p"
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44,
7,
3,
2,
2
],
"text": [
"Not a scientist but I read somewhere that when the ice melts the additional water creates more overall surface area of water. That additional surface area is more water the sun can heat up.",
"You can sort of think of it like a glass of ice water on a hot day. Ice water is 32°F (0°C) even when the ice is melting. However, once all of the ice melts, the heat is no longer just melting the ice it is instead heating up the water.",
"The world in general would get warmer because of the reduction in the albedo effect. \n_URL_0_ \n \nELI5 The ice caps reflect some of the light from the sun back out into space while water in the oceans absorb most of the sunlight that hits it. At a global scale reflecting sunlight means less heat, absorbing sunlight means more heat.",
"Warmer. If the ice caps melted, it would likely be caused by, or at least in tandem to, rising ocean and atmospheric temperatures, which means the ice caps are melting because the ocean is warmer, not the other way around. ",
"From looking at other responses I get the idea that people think it's a very linear question: a+b=c. \nChanges in albedo is a big concern, but the ice transferring temperature (like in a glass of ice water) is not as significant. \nThe added fresh water from melting ice creating density differences could slow currents and water circulation.\n",
"It depends where you live, the uk for example would most likely get cooler, due to the fresh water disrupting the tropical currents that make it warmer here, i think? \n\nAnyone able to expand on this or correct me if I am wrong? "
]
}
|
[] |
[] |
[
[],
[],
[
"https://en.wikipedia.org/wiki/Albedo"
],
[],
[],
[]
] |
||
5fz68v
|
How much did the experience of the French Resistance against the Nazis inform French strategy against insurgencies in places like Algeria and Vietnam?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5fz68v/how_much_did_the_experience_of_the_french/
|
{
"a_id": [
"daoevov"
],
"score": [
2
],
"text": [
"I don't have a good answer for you, but episodes 39 and 40 of the AskHistorians podcast cover \"Algeria and Counter-Insurgency\", so you may be able to find some relevant information there. You can listen here: _URL_0_"
]
}
|
[] |
[] |
[
[
"https://soundcloud.com/user679855208"
]
] |
||
1d5sc7
|
During the Cold War was their every controversy over kids having to read authors such as Tolstoy, or Dostoevsky in school because they were Russian?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1d5sc7/during_the_cold_war_was_their_every_controversy/
|
{
"a_id": [
"c9n6tw2"
],
"score": [
28
],
"text": [
"As far as I've read, Americans embraced many of these pre-Soviet authors more widely than the Soviets did. Particular Dostoevsky. He was castigated and discredited by the Soviets because of his views of radicalism, his works on Orthodoxy, and his sharp criticism of nihilists and revolutionaries. Especially his book 'Demons', also translated as 'The Possessed.'\n\nTolstoy was more embraced by the Soviets, so I'm not sure how he was received in the US during this time. But I'm pretty sure that these Russian/non Soviet authors were still revered as being what they were."
]
}
|
[] |
[] |
[
[]
] |
||
j4zqg
|
keynesian economics
|
Could someone please ELI5 what Keynesian Economics is and which political party typically supports Keynesianism and for what reasons? It seems to be a hot topic now in regards to the legislation in Congress about the Debt Ceiling, and I'd like to know more.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/j4zqg/eli5_keynesian_economics/
|
{
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"text": [
"Keynesians believe that recessions can be caused by nothing more than a vicious cycle:\n\n* People are getting laid off.\n* Laid off people conserve their savings very carefully.\n* Other people who are worried that they'll get laid off too conserve their money too.\n* People conserving money means that business have fewer customers.\n* Fewer customers causes more people to get laid off.\n* And so on, and so forth.\n\nUsually, something \"real\" (like a banking problem) triggers the vicious cycle, but once's it's going, it's self-perpetuating, even after the underlying problem is fixed.\n\nKeynesians believe that the solution is to interrupt the cycle. One way to do this is for government to go on a short-term buying spree. This is called \"stimulus.\" Basically, the government is just making sure that businesses have at least one customer: the government itself. This prevents further layoffs, which eventually causes people to relax and stop worrying about getting laid off, which causes them to start spending money again. Once regular people are spending money again, the government no longer needs to be the \"customer of last resort,\" so the government can then stop with the short-term buying spree. Thus, the cycle is broken.\n\nIt's important to realize, though, that people, once they become afraid of losing their jobs, they don't get over it instantly. Because of that, these short-term spending spikes need to last more than a few months. If they don't, then the effect is minimal.\n\nSome people think that tax cuts are stimulus. In fact, if people take the tax refunds and save them because they're afraid of losing their jobs, then that's not stimulus at all. It's only if they go out and spend the refund that it becomes stimulus. In general, some percentage of a tax refund will get spent, and some percent will get saved. So a tax cut should be viewed as (say) 50% stimulus, whereas government spending is 100% stimulus.\n\n",
"I've tried to make this short and sweet. Keynesian Economics, most simply could be thought of as such:\n\n* \nThere exists a cycle in the economy, in which there are years of success and growth, followed by years of depression or recession, where the economy is not doing well and people are unemployed and business is not good. This is called the *business cycle*.\n\n* The best way to combat this is by doing two things. During the good times (the *boom*) the government should have high taxes and lower spending, because everyone is doing well. During the bad times (the *bust*) the government should lower taxes and increase its spending to make up for the lack of business. This spending is called a *stimulus*, as it is intended to create activity within the economy. \n\nMost economists today are primarily Keynesian-influenced. Keynesian thought has spread so far that there are several different takes on his economic theory (such as Neo-Keynesians, New Keynesians, Post-Keynesians, etc). The Democrats are definitely the Keynesian party, though many Keynesian economists have criticized Obama for not doing enough with his stimulus and now cutting government spending. Republicans, however, have *recently* taken a decidedly anti-Keynesian approach. They now prefer a mix of Austrian, Supply-side, and Monetarist economics, which are schools favouring less government intervention in the marketplace, and lower taxes.",
"I believe all things should be handled in the form of a rap battle - and for that reason i submit to you Keynes vs Hayek in 2 parts.\n\n_URL_1_\n\n\n_URL_0_\n\nTLDW; both parties are Keynesian (with the exception of the conservative Libertarian camp) - who more or less believe that flooding the markets with lots of cash will help to stimulate positive growth when people are fearful to spend cash and take risks (especially during recessions). \n",
"\nThink of your five-year-old self as the government, and the economy as a minibike. To ride on it you have to do some stuff like keeping the throttle running and the steering steady. But you live on a street that's covered with patches of sand, and every time you hit one it slows the bike way down, veering it off course and occasionally knocking it over. You and your friends have tried ways to sweep away the sand or keep it from piling up, but mysteriously, they never seem to work. The sand keeps coming back.\n\nSo the next best thing is figuring out the best way to ride your minibike on this street, and your bike mechanic buddies disagree on that. The Keynes kid says to goose it harder when you hit a sand patch, to get through it faster and keep from falling over, and make up for it by easing off when you're back on asphalt. Some kids say you should build up lots of speed first, so hitting a sand patch doesn't slow you down as much. Others say you shouldn't do anything special, it won't help and just wastes gasoline. One says the minibike will ride better by itself if you stay home entirely, but most kids think he's been eating glue.\n\nYesterday you hit a really huge sand patch, tried Keynes' advice and goosed it really hard, and got through it - but still almost crashed, and burned through a lot of your gas tank, and came out the other side barely moving forward. Your buddies are so alarmed over this, they're arguing about their different suggestions. Keynes says you should have goosed it harder, the exchange student from Austria says you should have rode it out, the guy from the supply store says you should have worked up more speed before hitting it. An hour ago it sounded like they might agree on a solution to handling sand patches, but now it only sounds like shouting - and the argument has drifted from what to do about sand patches, to each kid telling the others they're lousy riders. You're not sure that's gonna be useful advice the next time you hit sand.\n"
]
}
|
[] |
[] |
[
[],
[],
[
"http://www.youtube.com/watch?v=GTQnarzmTOc",
"http://www.youtube.com/watch?v=d0nERTFo-Sk"
],
[]
] |
|
18ukeq
|
As I understand it, the Sun's gravity force and the planets in our solar system's motion through space is "equal" and therefore we're not getting pulled towards the sun and neither drifting away. How did all the planets get the speed around the sun they needed to stay in a stable orbit?
|
askscience
|
http://www.reddit.com/r/askscience/comments/18ukeq/as_i_understand_it_the_suns_gravity_force_and_the/
|
{
"a_id": [
"c8i3xbh",
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2
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"text": [
"What would become the solar system began to coalesce out of a cloud of gas, some unknown perturbation caused a section of this gaseous cloud to collapse. The largest part of that matter condensed in the center as what would become our sun. The material that did not fall into the star spins around the star, due to the conservation of angular momentum. This also flattened this matter into a disk. So we have the matter which fell into the star, then we have the matter that flew off into space and was lost. Lastly we have the matter which remained in orbit and became this protoplanetary disc. From this disk, the planets coalesced. Since they coalesced from material in orbit, they essentially simply maintain the original motion of their particles.",
"The planets got that way by being created in orbit. First there was [a huge cloud of dust from one or more novas or supernovas](_URL_0_). When a star explodes, all the elements higher than iron are created. There would also have had to be a lot of hydrogen too. Most likely there was a large cloud of hydrogen, then one or more stars exploded nearby and the dust from those explosions hit the gas cloud and slowed down.\n\nThen the whole thing started to collapse, and as it collapsed it began to rotate. As it began to rotate, it began to flatten in the more tenuous outer regions, while the inner region collapsed into a sphere.\n\nThere would be local collapsing going on too in the outer regions, as small differences in density led to major differences over time, and a small lump became a larger lump, which eventually began to collapse under its own gravity to form a proto-planet.\n\nBy that time, the orbits would have worked themselves out from the initial conditions. Inner planets move more quickly than outer planets."
]
}
|
[] |
[] |
[
[],
[
"http://aether.lbl.gov/www/tour/elements/stellar/stellar_a.html"
]
] |
||
1ws2tp
|
if opposition groups don't like the government, why do they boycott elections?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1ws2tp/eli5_if_opposition_groups_dont_like_the/
|
{
"a_id": [
"cf4v2ry"
],
"score": [
2
],
"text": [
"If you think that the government is corrupt, if you boycott the elections and they get elected you can just continue saying they are corrupt.\n\nIf they actually ARE corrupt, then if you participated they'd just ignore your votes and put themselves in power but be able to say that the entire country supported them.\n\nIf they AREN'T corrupt, then you can continue opposing them for whatever actual reason you oppose them, while calling the elections illegitimate because the people didn't trust them to begin with."
]
}
|
[] |
[] |
[
[]
] |
||
3z0596
|
why do people still have problems conceiving? wouldn't evolution mean that those with 'poor' genes wouldn't persist? or are all problems with conceiving environment related?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3z0596/eli5_why_do_people_still_have_problems_conceiving/
|
{
"a_id": [
"cyi6fsq",
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2,
3
],
"text": [
"There's a mass variety of reasons.\n-birth/growth defects\n\n-doing something wrong (Ie having sex 24/7, or not around ovulation)\n\n-trouble conceiving doesn't necessarily mean they will never have a kid\n\n-traits can skip generations\n\n-genetic mutation\n\nAlso, evolution in the human race has pretty much stagnated. With so many people, and with so much technology, it's pretty much impossible for such people to \"breed out.\"",
"usually because people wait so long to get pregnant. an 18 year old couple can get the woman impregnated really easily. 35, not so much.\n",
"Biologist here\n\n1) Every person is a mixture of the DNA of their two parents. The DNA of each parent might work fine, but doesn't always work when two peoples DNA gets scrambled together. Negative traits can emerge from the wrong combinations of traits that might be fine in different combinations. If you have the wrong combination of genes, all kinds of things can go wrong, and one of those things might be reproductive problems. \n\n2) sometimes two people don't have compatible genes. Person a may not be able to conceive with person b, but they work just fine with person c. \n\n3) Evolution is not always good at removing every single bad trait. There are a variety of reasons why bad genes can persist in a population, including gene linkage. \n\n4) Every trait has some genetic component to it, but not every trait has a large genetic component. For example, having an unpleasant personality is often pretty negative, but genes only account for a small to moderate amount of the variance in personality. \n\n4) New negative traits can always be created through mutation, and evolution just hasnt had the time to fix it yet. Every one of us carries new mutations, although estimates vary on how many new ones we each have -- the estimates range from a few to a few hundred. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
1lzh16
|
why is that in the same room, same temperature, my boyfriend can be sweating while i am shivering?
|
We are close to the same height. If we are wearing the same amount of clothing - or even if he is shirtless and I am wearing a sweater, he can be sweating while I am so cold I am shivering. Why do we feel THAT different?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1lzh16/eli5_why_is_that_in_the_same_room_same/
|
{
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"Does he have a higher body fat than you? Fat is very insulating and would explain for it. \nAlso is he active and take part in a lot of sports? A faster metabolism will keep you warmer, you've probably noticed after intense exercise you feel warm for hours after. ",
"There's a region in the brain responsible for temperature regulation, and it seeks to set your body temperature to whatever it deems best. That may vary slightly among people. When it (the hypothalamus) sets your body temperature above what it currently is, you shiver - this rapidly burns metabolic fuel which releases energy as heat. If your set point is below your current temp, you sweat, as the evaporation off the skin will cool you down(related to the energy input required to vaporize water).\n\nAlong with normal variation between people, even in yourself you vary about half a degree centigrade throughout the day. This can cause a fair bit of difference in how our body reacts to a temperature relative to someone next to us.",
"It also it partially due to your different genders. Males are designed to get rid of excess heat, more of their blood vessels are closer to the surface of their skin. Females, are designed to hold heat in. It traces back to how your body is wired for reproduction. \nWith more blood vessels closer to the surface, he feels warmer. \nNow, there are always exceptions but this is a pretty good rule for how most people feel. I'd link to the article I read but I'm on my phone. I think I read it in r/askscience somewhere. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
77g8pr
|
How do Historians reading old documents correct for typo's, bad handwriting and other writing mistakes?
|
So like a lot of people I keep a journal. My hand writing is also just atrocious. Something I've thought about a lot is how do historians working on old documents figure out what's a typo/mistake, whats a regional difference and what's just what people actually called something?
This goes for pretty much every field, but as an example; If your reading the records written by a monk in Anglo-Saxon Wessex, all written in a cramped spidery hand writing, how do you separate mistakes from actual proper spelling/writing?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/77g8pr/how_do_historians_reading_old_documents_correct/
|
{
"a_id": [
"dolmd5h"
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"text": [
"tl;dr: Plenty of experience and good pattern recognition skills.\n\nMy background in this: I'm in the [natural history] museum field where we sometimes have to \"decode\" old, handwritten labels and field notes; have participated in a historical transcription project; and am a beginner scribe in a living history group where more experienced scribes teach about this sort of thing.\n\nYou want to transcribe typos. You make note of what you think is one, but you never know when a typo might turn out not to be, or when a pattern emerges that tells you something else about language evolution. This is particularly true in pre-modern documents (speaking of English, specifically, since that's all I'm familiar with in this arena), when there was no standardized spelling. Shakespeare himself [famously spelled his name in multiple ways](_URL_1_). So, technically, there were no typos before standardization occurred. Oddities? Sure. But no dictionaries to say it's incorrect.\n\nBeyond that, it's a matter of getting enough experience making observations to say \"this spelling was correct in this time and place and that one is not\", or \"this person spelled this word in one way in a couple places, but mostly spelled it this other way, so the former was probably a mistake\". Or, in the case of my job, \"that's not how that species name is spelled in the original paper naming it, so it's a typo\". Hard-to-read handwriting...that just takes a lot of getting used to. Sometimes you have to stare at text for quite a while to figure out what's actually written there (I'm looking at you, [well-calligraphed gothic hands!](_URL_2_) Someone's added the dots to the i's in that pic, by the way. They wouldn't have been there earlier in period.). But the more you look, the better you get at it.\n\nEDIT to add examples from [a text I consulted while learning a hand](_URL_0_): 'J' used to not be a thing in English and 'Y' was variable. The scribe wrote \"reioyce\" somewhere in there and it was correct for him to do so. 'V' wasn't used for a while either. So \"double-u\" really did start out as two 'U's. You can see how 'V' and a double-v-looking 'W' start showing up on some pages in this manuscript. It was written across the time that shift became more commonplace in this scribe's region."
]
}
|
[] |
[] |
[
[
"http://www.wode.div.ed.ac.uk/",
"http://shakespeareauthorship.com/name1.html",
"http://www.calligraphy-skills.com/images/minimum.gif"
]
] |
|
7w9y9e
|
when investing in a mutual fund for retirement, where does the wealth come from?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7w9y9e/eli5_when_investing_in_a_mutual_fund_for/
|
{
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"text": [
" > where does the wealth come from?\n\nThe companies the fund invests in become more profitable over time, producing greater profits that pay out greater dividends to shareholders, increasing the value of the equity you hold via the mutual fund.\n\n > am I just making others poorer\n\nNo. The return you get is a portion of the increased wealth the company generated. If I take seeds and grow vegetables I've made myself richer without making anyone else worse off. In this analogy you are providing me with money to buy seeds and getting a cut of the profit I make when selling the vegatables.\n\n > contributing to the wealth gap?\n\nYes. In general, if you are able to save and earn a return on those savings you are accruing wealth far faster than someone who cannot afford to. As such, you're growing richer far faster than someone who is poorer. \n\nThat said, it is pretty much completely incorrect to say that that is bad for society.",
"Everyone's work has value. Over time, that work adds up into money. Think of it like you're buying wood for carpenters. They need the wood to make furniture. Then in turn, you get a cut of the profits. Money supply increases as the value of goods increases. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
zs6zc
|
What are the origins of the Signs of the Zodiac?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/zs6zc/what_are_the_origins_of_the_signs_of_the_zodiac/
|
{
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"c67b9gq"
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"text": [
"The ancient Babylonians - who also invented the 24-hour day, the 60-minute hour, and the 360-degree circle - divided the night sky into 12 sections, to make it easier to say where a planet was as it moved through the night sky (planets were obvious things to keep track of, as they were the only \"stars\" which moved - 5 of them). \n\nHowever, there are no longitudinal markers in the sky, to mark the end of one section and the start of the next. Therefore, they identified one constellation in each section, and named each section after its main constellation. The first section was defined as the one that the Sun entered at the northern hemisphere vernal (spring) equinox. This section was named after a constellation of a ram it contained. The next section had a constellation representing a bull, then a crayfish/crab, and so on.\n\nThe *names* of the signs that we currently use came later, from the Greeks and Romans, who acquired the Babylonian astronomical methods. For example, the Latin for \"ram\" is \"aries\", for \"bull\" is \"taurus\", for \"crab\" is \"cancer\", and so on. The word \"zodiac\" itself comes from the Greek for \"circle of little animals\".\n"
]
}
|
[] |
[] |
[
[]
] |
||
nz83a
|
Why am I able to smell something I'm no longer around?
|
Long story short, last night I was at a party where people were smoking weed. I don't smoke but but the smell was very pungent. It's a day later, I'm no longer around it and yet every once in a while I smell a little bit of marijuana. Why is this? Is it psychological or perhaps the smell is physically trapped in the mucus in my nose?
|
askscience
|
http://www.reddit.com/r/askscience/comments/nz83a/why_am_i_able_to_smell_something_im_no_longer/
|
{
"a_id": [
"c3d657o"
],
"score": [
2
],
"text": [
"The chemical that's responsible for the smell may very well be deposited onto _anything_ in the vicinity. That includes your body, your clothes, etc."
]
}
|
[] |
[] |
[
[]
] |
|
ezla7q
|
Do deaf people experience subvocalization in a similar manner as those who aren't deaf?
|
askscience
|
https://www.reddit.com/r/askscience/comments/ezla7q/do_deaf_people_experience_subvocalization_in_a/
|
{
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"fgpzuls",
"fgqufig"
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5
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"text": [
"Their form of that would be instead of imagining the sounds, imagining the lip movements they may have learned from talking if they ever did and visualizing the words, or translation from visual word to what a certain word in sign language may look or feel like to perform.",
"Assuming your queation means they can read a word and hear it in their imagination as they read it, I assume that is an example of what you are talking about.\n\nThe short answer is it depends on how they went deaf. For example, somone born blind will not dream with vision, as they have no referance point, but if you go blind, you can dream with vision. The same applies to the deaf. Describing sound to a deaf person is like describing blue to the blind man. Deaf people can learn to speak, but not verry well, because they have no idea if they are saying the word right, they have to rely on a hearing person to do that. But the answer to your question is no, if they were reeding they would not hear the words in their head assuming they have been deaf since birth.\n\nSource; learned basic sign language from a person who went deaf at 9 months and has no memory of hearing."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1rnf5r
|
my friend brought over some glass bottled beer that was room temperature and said that if we wrapped them in wet paper towels and put them in the freezer, they would get cold faster. is this true?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1rnf5r/my_friend_brought_over_some_glass_bottled_beer/
|
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"Yes. The water in the paper towels will chill and freeze quickly, and since it's both denser than air and held directly against the bottle, it will help draw heat out of the bottle. \n\nIts not going to give you an icy beer in minutes, but it will speed the process along. ",
"John Green tested this in a Mentalfloss video. Apparently it works.",
"You can also put them in a bowl with water, ice and salt. This can give you chilled beers in a few minutes.",
"This works really well if your trying to get a bottle of something cold. Once the paper towel freezes shake the bottle to move the liquid around. You can chill a bottle of whiskey in 10 minutes. ",
"You could always... oh, I don't know... try it?",
"Within the freezer is a microclimate. There is a movement of moisture to the evaporator( old freezers would build huge blocks of ice by moving moisture from products to the evaporator coils , while newer \"frost free\" refrigerators have a defrost cycle, regardless of which kind the movement of moisture is still happening )\nThe evaporation of water carries with it a massive amount of heat.\nThe bottle of beer with a wet paper towel will experience evaporation of the water soaking the towel, this evaporation wicks heat out of the beer bottle faster than if you let the cold climate of the freezer cool the beer normally.\nSo yes the wet paper towel boosts the cooling process.\nFor a scientific understanding google \"latent heat of evaporation\"\nSource: 18 years of HVAC experience",
"The way to cool a drink the quickest is to put the bottle on top of a bowl of ice and slowly rotate it. The rotating of the liquid cools it all, instead of just the sides. One minute of spinning a can of soda in ice gives you a nice cold soda. ",
"If you want an even faster chill, put a small, deep container, big enough to hold a beer bottle, fill half full with rubbing alcohol, put it in your deep freeze, upright. If you leave it there, it will come down to your deep freeze temperature. Then, when you need to rapidly chill a beer, put it in the alcohol. 2-3 minutes, and you've got a deliciously cold beer...!",
"A wet paper towel will freeze very quickly, therefore applying freezing cold to the entire surface of the glass. like shoving them into the snow. It will quickly chill your beer.",
"Two things:\n\n1) Modern Frost-Free freezers circulate warmer dry air periodically to melt and evaporate frost. This has the affect of causing evaporation cooling to the wet paper towel that cools the beer.\n\n2) A wet paper towel increases the surface area the beer to the wall(s) of the freezer. It will likely freeze the paper to the walls, but it helps conduct heat from the bear directly to the surface of the freezer walls. It's basically the same effect as adding thermal past to a heatsink."
]
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|
[] |
[] |
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4lei3h
|
why currency appreciation is bad?
|
In my very basic understanding of economics, it seems that having a strong nation currency is good.
Yes, appreciating currency hurts the exports and make imports cheaper, but is this downside that bad?
What are the benefits and drawbacks of appreciating currency?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4lei3h/eli5why_currency_appreciation_is_bad/
|
{
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"If you are in a position where your economy depends on cheap exports you would want to keep your currency relatively weak compared to your trading partners. Because if your exports get too expensive, they'll go somewhere else and you won't have an economy.",
"It's a little bit complicated since the money supply is affected by a number of factors including economic inflation and recession as well as the money transmission mechanism. Fiat currency has no intrinsic value so it's not as if your dollar can buy more or less based on it's singular value. Also since we exist within a global market currencies value can change based on demand for said currency. \n\nHeres a situation: If there is a high demand for American goods, there will be a high demand for American dollars thereby causing the dollar to appreciate in value. As the dollar appreciates demand for American goods decreases until the dollar decreases in value and over time demand returns... But we like growth... So what the central bank can do is lower the interest rates. By lowering the interest rates they discourage saving thereby increasing the money supply and depreciating the dollar. This is what drives GDP growth. "
]
}
|
[] |
[] |
[
[],
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] |
|
5qt88d
|
how can malware get installed on your computer just by openning up a website and without the user getting notified about a download?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5qt88d/eli5_how_can_malware_get_installed_on_your/
|
{
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"text": [
"in general it just shouldn't be possible, everybody knows that this is a big security risk. Usually JavaScript and everything that allows your browser to run code on a homepage is the source of all evil. You just don't know exactly what this code will do on your computer. People try hard to make it save but programs have bugs and programmers don't always think about all possibles uses of the tools they develop.\n\n\nA basic approach of hacking is sending a string to your browser that gets executed and in some way nobody considered yet this code gets more rights to execute and write stuff on your computer than it should have. \n\n\nAnd i have to give credit to the hackers who develop those things. It is really hard and requires a lot of knowledge about a browser to do things like that. And as soon as other people notice how the code works they usually improve the browser to prevent something like it from happening again. \n\n\nBut nowadays most malware works by abusing the human mind \"click here for free iphones!\" or an email that says \"man, look at this picture i send you!\" or \"check out this cool game!\" are a lot easier to create and use.",
"Through exploits in insecure software, which downloads and executes something without the user noticing. An example of this insecure software is often Adobe Reader. Attackers basically make Adobe Reader have an error and then they use this to execute some code. \n\nAs soon as you can execute some code on a system you can basically control it. You can download more code to execute and do harm.",
"When you load a webpage there are things going on in the background to make that possible. For example images are downloaded and displayed, scripts are executed, plugins loaded etc.\n\nEvery time a program gets an input and does something with it there is a chance that such input is malicious (not the kind of data that the program normally deals with) and this fact should be accounted for by the programmer and dealt with in a graceful manner.\n\nHowever programmers do make mistakes and sometimes such malicious inputs aren't dealt with correctly and and the program can be derailed in its execution by such malicious code.\n\nFor example, the browser takes some picture in a website and decodes it so it can display it to you and the programmer didn't make sure to check that only precisely the size of the image can be loaded into memory, not a byte less not a byte more. An attacker can use that fact to create a particular image file that tricks the software into loading in memory more than it should which in turn causes it to write in an area of memory that enable the attacker to execute code.\n\nNow in a scenario like this it means that just by loading an image some code, aka a program, would be executed without any further action by you.\n\nFortunately most of these issues come from plugins like java or flash, which means that disabling them greatly reduces the risk of being victims of such attacks.",
"Because of bugs in your browser, or plugins installed in your browser. This is usually done with a buffer overflow attack to enable executing the data that was downloaded. The basics of this are as follows \n \n1. Flash wants to read part of the downloaded data, for instance to display a message. \n2. It thinks it only needs only 200 bytes to store this data, because that's usually the maximum size the data is, so it allocates 200 bytes in memory to store it.\n3. It starts to read the data, looking for the end of the data, usually denoted by a byte with the value \"0\". \n4. The specially crafted file actually contains invalid data, and will contain more than 200 bytes before a \"0\" is encountered. \n5. The program will continue copying the data into memory past the end of the 200 bytes it originally allocated. \n6. The extra data overwrites data in memory that was supposed to be executed later on by some other part of the program. \n7. The new stuff gets executed and you now have an infected computer. \n\n \n Usually the 2 biggest culprits are Adobe Flash and the Adobe PDF Reader. But there have been other exploits such as the standard Windows JPEG processing library, which could cause your computer to be infected simply by downloading an image to be displayed in the web page.",
"Malware is mostly spread through security vulnerabilities on your computer,\nfor example in your browser or some plugins your browser uses.\n\nThe most common ways for an infection are through JavaScript or the Flash\nplugin. Someone might find a bug in Adobe Flash to manipulate it into running\narbitrary code. Using this bug, he downloads the real malware to your computer\nand executes it. Since this still requires you to visit a website that serves\nthe exploit and quite sure you won't visit some site like\n_URL_0_ too often, there is often another step in the whole\nattack campaign like hacking a advertisement network and serving the exploit\ncode via advertisements. This way every website that includes ads from the\nhacked network, will serve the malware (that's why we love ad blockers ;)).\nAnother way to spread the exploit are so called Cross-Site-Scripting\nvulnerabilities in websites where a attacker can inject JavaScript code in a\nwebsite that will get executed when a user visits the website.\n\nBut using vulnerabilities in your browser or the plugins aren't the only ways\nto infect your computer. Another way that was described not to long ago but\nonly in theory (never seen in the wild) was to infect Fedora Linux using the\nfact that Google Chrome will download files without prompting the user and\nFedora will automatically index the downloaded files and create for example\npreview images for pictures or video files to show in your file manager. A\nattacker could cause Chrome to download a manipulated media file, that would\nbe stored on the disk and processed by the multimedia engine used by Fedora\n(called gstreamer). Due to a bug in gstreamer, when processing the manipulated\nmedia file, the attacker could execute code on the computer.\n\nAll in all, to infect a computer without user interaction the attacker needs a\nvulnerability in any program you use or multiple minor bugs combined in a\nclever way.",
"I answered this [yesterday](_URL_5_). Here's a copy of my answer.\n\n > A modern web browser is a complicated beast, with lots of different capabilities. It can do pretty much everything, from displaying complex graphics with custom fonts and playing audio and video in a variety of formats, to showing PDFs and doing all sorts of computationally intensive tasks. Browsers can also have addons and plugins, such as Flash, Java and Acrobat Reader. Websites can use your webcam and microphone, and access your local files, although only if you give it permission.\n > \n > Having the aforementioned capabilities means that browsers have a lot of complicated components, each with a lot of code. More code means more bugs, and some bugs can be abused by an attacker to take over your computer or steal your data.\n > \n > Getting infected by just visiting a website isn't that common these days, but it's still entirely possible, especially on shadier sites. Browser developers are pretty fast at fixing known exploits, but sometimes hackers use [zero-day vulnerabilities](_URL_2_). Keep your browser up to date and pay close attention to which websites you visit, and you should be safe.\n\n > [part 2]\n > \n > Yes, normally web pages can only save certain kinds of data, but certain bugs can lead into [arbitrary code execution](_URL_1_), meaning a carefully crafted web page can execute any code the attacker wants on your computer.\n > \n > Image, video, document and font formats can be quite complicated. For instance, two years ago [Google engineers discovered](_URL_0_) that a bug in Windows's font handling enabled carefully crafted font files to run arbitrary code on your machine. Since web sites can embed custom fonts, any website could've abused this.\n > \n > Plugins are also a common source of exploits. [Here's an example from this week.](_URL_3_) Cisco has a popular browser plugin called WebEx which is used for video calls. The plugin has to communicate with programs installed to your PC. Due to the incompetency of Cisco's programmers it's not limited to just communicating with their program, or only being usable from their website - any website can do anything to your computer. This applies to any browser the plugin is available for.\n > \n > Websites use Javascript as the programming language. Once again, things are complicated, so a serious bug in the language implementation can be exploited for who knows what. Almost every page already executes some code on your machine, and while it's limited to only certain things, breaking out of that [sandbox](_URL_4_) is not impossible.\n"
]
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[] |
[] |
[
[],
[],
[],
[],
[
"askdhfawej92nd09a32nd.com"
],
[
"https://googleprojectzero.blogspot.fi/2015/07/one-font-vulnerability-to-rule-them-all.html",
"https://en.wikipedia.org/wiki/Arbitrary_code_execution",
"https://en.wikipedia.org/wiki/Zero-day_\\(computing\\)",
"https://bugs.chromium.org/p/project-zero/issues/detail?id=1096",
"https://en.wikipedia.org/wiki/Sandbox_\\(computer_security\\)",
"https://www.reddit.com/r/explainlikeimfive/comments/5qigkm/eli5_how_could_simply_opening_an_3mail_or/dczhqhg/"
]
] |
||
18fo0d
|
How are new alloys developed? Is it just trial and error, and hoping you get lucky, or do we have ways to somewhat reliably predict their properties?
|
I don't know if such a thing exists, but if I were to mix two random metals together (I know alloys can include non-metals), let's say, I dunno, tungsten and niobium, is there anyway to predict the properties of this alloy at a given proportion of one to the other? Obviously things besides the choice in components are going to go into its properties, but in general is modern metallurgy at the point were materials scientists aren't just shooting in the dark?
|
askscience
|
http://www.reddit.com/r/askscience/comments/18fo0d/how_are_new_alloys_developed_is_it_just_trial_and/
|
{
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"No it is more trial and error than predictable behavior. What we have done is improved sampling amd testing techniques to really zone in on the characteristics we want. \n\nAlso,how the alloy is treated and processed is just as important as its mix.",
"That said, there is new research in the direction of modelling theoretical alloys. [MIT researchers announced this back in August.](_URL_0_)"
]
}
|
[] |
[] |
[
[],
[
"http://www.technewsdaily.com/6131-mathematical-shortcut-create-new-metals.html"
]
] |
|
5nsvbq
|
sometimes my phone's change with go from say 3% to 7% if i leave it alone for a long time. is it actually regaining charge?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5nsvbq/eli5_sometimes_my_phones_change_with_go_from_say/
|
{
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"text": [
"Your battery app calculates the remaining battery based on the battery power currently being used (mV) and your usage since it was fully charged.\n\n That's why you can generally do calibration to correctly measure the current battery status and range of it.\n\n Usually, if we ignore very little variations in the battery power, it goes down. So either your phone's forecast was wrong, or if the battery usage is lower than the expectation, in which case the battery level showed on your screen will increase a little. \n\nHope it was clear, English is not my native language, sorry about that. ",
"This mostly is because of how batteries work, it has two materials in it (usually plates of something), connected to electrodes. Charged ions move between the plates during discharge, and causing the current to flow. When the ion gets to the other plate it undergoes a chemical reaction and makes that spot on the battery discharged.\n\nHowever, the ions generally land on the surface of the plate, and make it so there are no more fully charged surface spots, even though there may be plenty inside the plate. The voltage of the battery is ultimately determined by how much charged plate space is exposed inside the battery. When a plate has an uneven distribution of charged spots, the ions tend to move around and even out (slowly), and drawing a large current quickly causes the surface of a plate to discharge. These two effects mean that if you quickly drain the battery it's voltage will drop quickly, in fact it will drop quicker than it normally would if you drew the same energy slower. This effect can be quite large, if you have a fully charged battery and short it, it will instantly drop into the millivolt range, but after removing the short it will restore it's voltage to something that closely resembles it's charge.\n\nSo it's the fact that the voltage is load dependent, with a time lag, that causes this error, your phone uses mostly voltage to determine charge. Doing something like quickly draining the battery then letting it idle can easily make it appear the charge went up. This is also why a dead battery can still read good if tested with a volt meter, it doesn't apply a load, so the voltage actually reads high, not something reflecting it's charge."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1jcyq3
|
what is the process of creating a maze in a cornfield?
|
Specifically ones when viewed from a distance create an image. From the planning, to actually cutting plants down, how is it done?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1jcyq3/eli5_what_is_the_process_of_creating_a_maze_in_a/
|
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],
"text": [
"I actually saw the process at Roba's farm in NE Pennsylvania. They've done a ton, from Romney and Obama, to planes, to a beehive (last year's).\n\nThey start by planting a large farm of corn. Usually the corn grown isn't sweetcorn, which is edible for humans, but a different breed of corn, used as animal feed.\n\nThe pattern for the 'picture' is drawn out on grid paper, and is then blown up the same way those 'copy-the-grid' pages in coloring books work.\n\nRight before they grow more than a foot tall, they trample/rip up the areas that are walking paths and then mark them off.\n\nWhen the harvesting season comes, which is most popular for mazes, they put up wooden fences (usually, in the nicer ones) to prevent you from cutting through it.\n\nIn the case of Roba's, they'll put map areas deep in the maze, and you have to visit all of the 'map stations' to get the pieces of the map.\n\nI hope that answered your question."
]
}
|
[] |
[] |
[
[]
] |
|
zlitv
|
why is new mexico so much more liberal than the other states surrounding it?
|
It seems to me that if you look at a [political map](_URL_0_) of the United States, states tend to lean either Democrat or Republican in clumps - the west coast and northeast are liberal, the Great Lakes area is somewhat moderate and diverse, and the rest is conservative. Yet for some reason New Mexico is the only state in the south that is strongly liberal (along with Colorado to a smaller extent), even though all the states surrounding them are conservative. Why is that?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/zlitv/eli5_why_is_new_mexico_so_much_more_liberal_than/
|
{
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"c65mtcl",
"c65mw2s",
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],
"score": [
2,
4,
2
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"text": [
"I was wondering the same thing yesterday. Hope you get a good answer.",
"I am not really sure, but I do know this: New Mexico is one of only a few states that are majority-minority (I know that Hawaii is too, I don't know of any others). So, whites do not form an absolute majority in New Mexicos population, rather, other minority groups (mainly Hispanics) are over 50% of the population. Whites are slightly more likely to vote Republican, whilst minorities are slightly more likely to vote Democrat. Hispanics actually swing more easily than other minorities, Bush did quite well with them, but the Republican party today is barely even pretending to care, so they will go for Obama by a huge margin.\n\nMost of the other states in that region still have white majorities, so they are a little more Republican. Actually, at the state level New Mexico votes Republican quite often, they have a Republican Governor right now I believe. But NM is safe for Obama this year due to the Republicans open hostility to Hispanics.",
"New Mexico is almost majority Latino and has a large Native American population, and those groups are mostly Democrats, and a lot of the white population in Santa Fe is liberal."
]
}
|
[] |
[
"http://elections.huffingtonpost.com/2012/romney-vs-obama-electoral-map"
] |
[
[],
[],
[]
] |
|
5rfioh
|
what is fair tax and flat tax?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5rfioh/eli5_what_is_fair_tax_and_flat_tax/
|
{
"a_id": [
"dd6srv1",
"dd6usys"
],
"score": [
7,
3
],
"text": [
"A flat tax is one of two things. \n\n1) You charge the same exact tax to every person. So if the tax is $2000 you charge everyone $2000. \n\n2) You charge everyone the same percentage. So everyone is taxed at say 30%. \n\nThe issue with a flat tax is that it hurts the poor more than it hurts the rich, as there are no exemptions or deductions. Everyone owe a flat percentage of their income, and due to the costs of the government that percentage has to be set high in order to get the money it needs to function. \n\nA fair tax does not means anything specific, but I think you are asking about a progressive tax. In a progressive tax you take into account how much harm a tax will do to someone. So the poorest will pay no taxes, and you gradually increase the amount paid in tiers going up 5% or so per tier. This is more \"fair\" because it does less harm. $2000 means a lot when it is 1 months pay or more, but it does not really mean much of anything if it is 1% of your salary. ",
"The term fair tax is subjective, depending on what is viewed as \"fair\", but I can tell you what a flat tax is.\n\nIt is generally regarded as a system of income tax where everybody, regardless of income level or possible deductions under current tax law, pays the same percentage of their income as tax. It doesn't matter if you make 20,000 or 2 million, you both would pay whatever it is, be it 10%, 20%, etc. Under most versions of the flat tax, there are no deductions, reinforcing the idea of it being flat and unchanging. Currently in the US, and Europe, and most of the world, taxes operate using brackets, where different levels of income are taxed at different rates. Keep in mind, income is only taxed at the bracket it lies in. If I make 100,000, at the first 10,000 is tax exempt, I pay no income on that. However, income between 80,000 and 100,000 might be taxed at 25%. \n\nThere are arguments for and against a flat tax, and whether it is fair. One argument for it is that since everybody pays the same percentage, and the same amount relative to income, its the most fair way of handling it. The argument against it is that affluent people have the ability to pay higher taxes without hurting themselves financially as much as the same tax would hurt a poorer person. \n\n "
]
}
|
[] |
[] |
[
[],
[]
] |
||
5b21zm
|
Found a bayonet in the attic, what are these symbols near the hilt?
|
[deleted]
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5b21zm/found_a_bayonet_in_the_attic_what_are_these/
|
{
"a_id": [
"d9l6u6u"
],
"score": [
6
],
"text": [
"The bayonet is most likely a Japanese Arisaka Bayonet from the World War II era. These markings are some of the ones used by the Toyada Jido Shokki Seisakusho Arsenal (Toyoda Automatic Loom Works, or TALW). Thus, these are the markings of the factory or arsenal which produced the bayonet (or at least the blade-- many factories of the era got various parts from other factories and put them together with the blade made by the labeling factory, which then got to mark the bayonet showing they had made it.)\n"
]
}
|
[] |
[] |
[
[]
] |
|
fw7qor
|
Should Nixon's Watergate scandal be seen as a unique and significant cause of the rise of American contempt/distrust towards government, or was it simply part of larger trend?
|
Sorry for the wordy title. Basically, was it a massive influence in and of itself, or did other events (Pentagon papers, Vietnam war in general, economic troubles in the late 60's/early 70's) drive the rise in distrust?
This is all assuming there actually was a rise in distrust in the 1970's - correct me if this is wrong.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/fw7qor/should_nixons_watergate_scandal_be_seen_as_a/
|
{
"a_id": [
"fmw1t5t"
],
"score": [
3
],
"text": [
"No one answered this? Well, the answer is yes, but, like most things, it is not that simple... What’s important to remember is that Watergate is not an isolated event, but an amalgamation of all of those things you mentioned, and some other things... Really, the decline of American idealism in politics probably began, in earnest, on November 22, 1963. The assassination of JFK is that watershed moment in history that you can’t shake free from no matter the topic, and it certainly has a direct role in Nixon’s presidency, and thus Watergate.\n\nBut, let’s focus on the events after 1968, leading to Watergate, and really, the event here is Vietnam. Simply put, from Vietnam, you get the Pentagon Papers. From the Pentagon Papers, you get the first (that we know of) blatantly illegal act by Nixon’s men; breaking into Daniel Ellsberg’s psychiatrist’s office. While this break-in goes unnoticed at the time, the two men who planned it are the same two men who planned the Watergate break-in. And, the men they hired to break-in to the psychiatrist’s office are the same men they hired to break into the Watergate. So, when the men are arrested inside the Watergate, the White House instantly goes into cover-up mode, by paying hush money, so as to not reveal this original break-in. This cover-up succeeds in getting Nixon re-elected, but ultimately comes undone, leading to Nixon’s resignation, as he was intimately involved. So, as you can see, the events as you mentioned are directly related.\n\nNow, back to your main question, is this the decline of American faith in their government? Keep in mind it wasn’t the crime of a cover-up that did Nixon in, it was the going on TV multiple times to give public addresses from the Oval Office, saying he had no involvement in the Watergate break-in *or any subsequent cover-up*. So, when Nixon ultimately releases the tape of June 23, 1972, the so-called “smoking gun,” and it is revealed he was involved in the cover-up from virtually day one, it marks a sort of loss of innocence in American politics. In a Gallup poll done in 1997, they covered this specific topic. The results are as follows:\n\n“A Gallup poll taken earlier this month updated several questions about public trust and confidence in government that were first asked prior to Watergate being widely reported. The results indicate that *Watergate triggered a decided shift away from high public confidence in the government* in Washington generally, but that it had much less effect on perceptions of specific aspects of government, such as the Executive branch, the Legislative branch, or even of \"politicians\" generally (defined as men and women serving in or running for public office).”\n\nFurther: “The greatest damage to the government's reputation as a result of Watergate appears to be in the amount of trust Americans say they have in Washington \"to do what is right,\" a question asked consistently by the University of Michigan since 1958 for its National Election Study. In 1972, before Watergate became the scandal of the decade, more than half of American adults gave the government very high marks, saying they could trust it all or most of the time, while 45% opted for the \"only some of the time\" alternative. By 1974, high trust had dropped to 36% and has remained below 50% ever since.”\n\n“...only 32% of Americans have a high level of trust in government to do what is right on this measure. Two thirds trust it \"only some of the time.\"”\n\nClearly, Watergate had a sizable impact on the American people, though like I said, Watergate was the culmination of prior events, namely Vietnam, which lead to the first resignation of an American president. It is the combination of those things that lead to where we are today. I hope that answers your question.\n\nSource: Gallup, *Americans’ Faith In Government Shaken But Not Shattered By Watergate* 1997\n\nWatergate source: *Watergate* by Fred Emery 1994"
]
}
|
[] |
[] |
[
[]
] |
|
exon6u
|
Why is nitrogen willing to give an electron?
|
For instance why is it willing to make NH4+
I don't see how an incomplete p2 orbital would give it more stability.
|
askscience
|
https://www.reddit.com/r/askscience/comments/exon6u/why_is_nitrogen_willing_to_give_an_electron/
|
{
"a_id": [
"fge35em"
],
"score": [
10
],
"text": [
"The N in ammonia (NH3) has a lone pair of valence electrons. A H+ cation has no valence electrons. The H+ is what brings the charge to the polyatomic ammonium ion when the N shares its lone pair of electrons with the H+ to fill its 1s orbital. The N atom does not give up any electrons in this arrangement. \n\nN atoms generally accept 3 electrons to make a N3- anion."
]
}
|
[] |
[] |
[
[]
] |
|
34w7t2
|
Why were the vast majority of Black Union soldier's deaths caused by disease during the US civil war?
|
Why were the vast majority of Black Union soldier's deaths caused by disease during the US civil war?
source: _URL_0_
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/34w7t2/why_were_the_vast_majority_of_black_union/
|
{
"a_id": [
"cqyr3ce",
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2
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"text": [
"**The soldiers of the U.S. Colored Troops were frequently sent to hostile environments rife with disease,** largely due to the belief that blacks suffered less from yellow fever, malaria and other tropical diseases than whites did. Exacerbating this problem was the fact that **many black enlistees were in poor physical health before they entered the U.S. Army.** Any health problems they may have had were aggravated by the fact that **black soldiers received poorer supplies, including food, shelter and medical care than white soldiers.** Black soldiers were worked hard in entrenchments and on construction projects, many sickened by such labor in unhealthy conditions. Furthermore, even minor wounds can become infected and fatal without attention.\n\nThe *Sanitary Memoirs of the War of the Rebellion* seem to be the source behind the link you mention, but there is other data available. Fortunately, [Volume 1 of those memoirs is posted online](_URL_1_), and if you turn to page 184, you'll also see the 1867 theory as to why the proportion of black soldiers dying from disease was so much higher:\n\n > \"These figures appear to indicate pretty conclusively that the negro, as he was found in our armies, was less capable than the white man of enduring the fatigues and hardships, and of withstanding the influences of disease incident to army life. ... What the causes of this greater susceptibility of the negro to disease are, hardly come within the scope of this paper; but it is suggested, to use the words of General Fry, 'that they were rather psychological than physical, and arose from lack of heart, hope, and mental activity, and that a higher moral and intellectual culture would diminish the defect.'\"\n\nOf course, Gen. Fry's words are so much bunkum.\n\nJames K. Bryant's *The 36th Infantry United States Colored Troops in the Civil War* concludes, \"The high death rates of disease among black soldiers, particularly of the 36th USCT, resulted from poor pre-war physical condition, excessive fatigue duty in constructing trenches and other military fortifications, and poor medical care.\"\n\nRemember, the men enlisting in the USCT were often escaped slaves and not the pinnacles of health that we associate with outdoor labor today. They were malnourished, and physical examinations \"revealed shocking signs of physical abuse received in slavery including scars from whips, burns, and mutilation.\"\n\nThere were few black doctors to serve in black units, and white doctors frequently refused to serve in black units or treat black soldiers. This meant that the USCT was chronically understrength in surgeons and orderlies, people who typically enforced sanitation orders in camp. Units with less care to latrines and clean drinking water could suffer high rates of dysentery and other waterborne diseases.\n\nThese poor conditions were not just present at the front or in battle camp. An October 1864 [report on a camp in New York](_URL_0_) states: \"For a considerable time the quarters provided for the colored men were insufficient and improper. Tents were furnished by the Government, but ... the men were greatly crowded; they were also without floors or means of warming, causing great suffering from cold. Disease began to appear to an alarming extent, while there was no proper hospital in which to treat it.\"\n\nLate in the war, adjutant general Lorenzo Thomas visited a USCT hospital in Nashville and found lice-infested wards with men still wearing bloody uniforms from battle. \"Words cannot describe the utter filthiness of what I saw,\" he said. \"Had these men been white soldiers, think you this would have been their condition? No!\"\n\nRacism was present from coast to coast. In the anthology *Black Soldiers in Blue,* John David Smith touches on the case of the 56th USCT in Arkansas. Limited to garrison duty, it lost 25 officers and men in combat — and 653 men to disease. Smith refers to the historian Ira Berlin, well-known for African-American and Southern history, who describes how Southern black soldiers sometimes would wait around white cookhouses to get food left over from white soldiers better-fed than they were.\n\nAs for disease, you'll want to refer to Andrew Mcllwaine Bell's *Mosquito Soldiers*, a pretty good breakdown of the impact that malaria and yellow fever had on the course of the war. ",
"Apart from the excellent answer below, it is also important to consider that the majority of deaths in all units, of all races, North and South, were from disease."
]
}
|
[] |
[
"http://www.civilwar.org/education/civil-war-casualties.html"
] |
[
[
"http://www.albany.edu/nystatehistory/44/USCT.html#Note12",
"https://books.google.com/books?id=HAUvDHr0gM4C"
],
[]
] |
|
1gejo0
|
why is paper money difficult to duplicate?
|
What makes it hard to forge paper money? What properties of paper money make it hard to forge and pass off as real money in everyday transactions? (not buying a car in cash or anything big)
If the answer is that it's not, what percentage of money in circulation is forged?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1gejo0/eli5_why_is_paper_money_difficult_to_duplicate/
|
{
"a_id": [
"cajgb8z"
],
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],
"text": [
"US money is made from linen which has a distinctive texture. It has a mixture of red and blue fibers scattered through it, special inks which change color depending on the angle, intricate patterns and smooth shades, micro print, embedded polymer strips with the denomination printed on it, and is infused with chemicals which will react with the ink of markers specifically designed to detect counterfeit bills. The ink of money even has a distinctive smell.\n\nAll of this combines to make forging money, if not possible, at least very difficult to do so profitably. It doesn't make sense to spend $25 to forge a $20 bill for example. Oh, and the Secret Service comes after you with black helicopters if you try it."
]
}
|
[] |
[] |
[
[]
] |
|
1o0fly
|
how do they determine launch locations for rockets/space shuttles/etc?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1o0fly/eli5_how_do_they_determine_launch_locations_for/
|
{
"a_id": [
"ccnqd30"
],
"score": [
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"text": [
"Short answer: That's where the launch pads are.\n\nLong answer: It really depends on what kind of orbit you're trying to accomplish. In general, it's useful to be closer to the equator, because that part of the Earth is spinning the fastest due to the Earth's rotation. Rockets launching from there and traveling east start off with that extra velocity from the Earth's spin. Orbiting is all about having enough velocity, so any extra speed that you can get \"for free\" is a big deal because it means you need less fuel. \n\nThe US chose Florida for most of their launch facilities because it's closer to the equator, and also when you launch a rocket east from there, it travels over the ocean, so if it explodes or crashes or whatever, it doesn't fall on populated areas."
]
}
|
[] |
[] |
[
[]
] |
||
2e78fb
|
Were full-face Viking helmets, like the one found at Sutton Hoo, regularly used in combat?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2e78fb/were_fullface_viking_helmets_like_the_one_found/
|
{
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"cjwvn4u",
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"text": [
"I believe that the Sutton Hoo helmet is Anglo-Saxon and not Viking, Historians believe that it's from the early 7th century and Vikings didn't start raiding England till the late 8th century. \n\nGot my info from the British Museum website: _URL_0_ ",
"Sutton Hoo is Anglo-Saxon and, if you buy Terry Gunnel's theory about space and performance in Anglo-Saxon England and early medieval Scandinavia, intended for ceremonial use moreso than battle.\n\nThat said, as far as full-face helmets from the 'viking age,' (whatever that is) are concerned, we don't have any evidence of them existing in the archaeological record, as we have only got three helmets which have been recovered - an intact one in Gjermundbu, and fragments in Tjele and Gotland. The fragments are similar to the Gjermunbju helmet, where there were 'goggles' which protected the nose and eyes, which might be based on earlier Vendel-period helmets, but again, we're not really sure considering we have only three exemplars.\n\nWe do know that helmets were used routinely, based on accounts in the sagas and on picture stones, but just what they looked like or what they were made of is, unfortunately, something we don't know for sure."
]
}
|
[] |
[] |
[
[
"http://www.britishmuseum.org/explore/highlights/highlight_objects/pe_mla/h/helmet_from_sutton_hoo.aspx"
],
[]
] |
||
g2tzmd
|
How does NASA calculate the orbits for missions between Earth and Mars?
|
As per this subreddit's rules, a cursory google search shows that I should be able to calculate the answer with Kepler's 3rd Law, where the period squared is equal to the semi-major axis cubed. but while this may work on paper, in practice none of the actual Mars missions have followed the theoretical values.
Every tutorial I find online assumes that Earth and Mars are in circular concentric orbits (which they aren't) and that the probes themselves travel exactly 180 degrees from one side of the sun to the other (which they don't).
**Math time:** Earth's semi-major axis is 1 AU, Mars' semi-major axis s 1.523679 AU. This means the Mars probe's semi-major axis is 1.2618395 AU. Applying Kepler's 3rd Law gives us a period of 1.417445 years. 180 degrees is half an orbit, so every Mars mission should take 0.708722 years (259 days), but the real world values vary wildly; the shortest mission took 131 days (Mariner 7), and the longest took 334 (Mars Polar Lander)
The distance between Earth and Mars is not uniform, so how do space agencies calculate the launch windows? How do they know exactly when to launch and how long it will take for their probes to reach Mars? How do they account for the eccentric orbits? Is there a more complex formula than Kepler's 3rd Law?
I feel like I'm asking too much at once. I apologize if my train of thought has gone off the rails. Let me know if this question doesn't make any sense. I can supply visual aids to help explain what I'm talking about if necessary; I've been trying to figure this out myself for months.
|
askscience
|
https://www.reddit.com/r/askscience/comments/g2tzmd/how_does_nasa_calculate_the_orbits_for_missions/
|
{
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"text": [
"I'm really not an expert on the maths behind celestial navigation, but I'll give this a go.\n\nThe *patched conic approximation* is useful for many trajectories. This works by dividing the solar system into distinct spheres of influence (SOI). For example our spacecraft launches in Earth's SOI, then does its departure burn. It leaves Earth's SOI and enters the Sun's, then later on it enter's Mars's SOI.\n\nWithin each bodies sphere of influence, you only worry about the gravity of that central body. This means your trajectory is a Keplerian orbit, which is a conic section.\n\nEarth's SOI is moving with the Earth itself, so when the spacecraft leaves Earth's SOI, you use the spacecraft's velocity relative to Earth and Earth's velocity relative to the Sun, do the vector addition to get the spacecraft's velocity relative to the Sun, which then defines a new Keplerian orbit. Joining the trajectories up like this is the \"patched\" in \"patched conic\".\n\nRemember, this is just an approximation, but for most stuff it's pretty close. And it makes the maths manageable. Still pretty advanced, but manageable. Patched conics will get you a draft trajectory that can then be fine tuned with full calculations of the gravity of each planet and moon.\n\nAnother important aspect is known as Lambert's problem. Given a start point, end point, and time of flight, calculate the unique orbit that fits that requirement.\n\nSo, take the start point as the location of Earth, which of course changes depending on the start date. Take the end point as the location of Mars, which depends on the date of arrival, or equivalently the start date and time of flight. Then by solving Lambert's problem, you get the unique trajectory between Earth and Mars for that start date and arrival date. (This assumes we aren't making a major course correction during the flight). Then use your patched conic approximation to get your trajectories away from Earth and into Mars in their respective SOIs. And from *that*, you know how fast you need to leave Earth; the slower you go, the less rocket fuel is needed. Similar the slower you arrive at Mars the less fuel needed to brake and get into an orbit - but that doesn't matter if you're just flying by.\n\nDo this to make a chart and you get what is known as a porkchop plot. In essence, it shows possible departure and arrival dates and how much delta-V is needed to do the flight. Pick a trajectory that doesn't need more delta-V (essentially, more fuel) than your spacecraft and its launch rocket has.\n\n_URL_1_\n\n_URL_0_\n\nOn a final note, the reason interplanetary trajectories usually aren't ideal Hohmann transfers is that planetary orbits differ in inclinations. If you did the ideal 180 degree transfer, you might well end up \"above\" or \"below\" Mars, and you can't correct that by changing your Earth departure burn. You can do a course change halfway but that means the spacecraft needs a lot of extra fuel. Doing a transfer that goes through a smaller or larger angle allows you to sort out the inclination with your Earth departure burn. That burn might be done with a rocket stage using hydrolox fuel that boils away if not used promptly, or a solid booster that can only be lit once - that sort of rocket stage couldn't do a mid-course inclination correction.",
"Kepler's third law is indeed not the best way to manage this.\n\nOne approach is to use the simple 2-body solution for gravity. Ignore Earth and Mars, as they are very far away for most of the trip. You can calculate an object's position in its orbit as a function of time, as orbits are ellipses with a focus at the parent body and energy is conserved, the equations are relatively easy to derive.\n\nThat's fine and good for estimates. For precision, they use recursive simulations. Basically, a 3D simulation where every physics tick the velocity and position are updated based on local gravity and velocity. This is actually easier to understand than the former technique, but it requires a lot of computing power to be sufficiently accurate. Fortunately, NASA has that."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Porkchop_plot",
"https://en.wikipedia.org/wiki/Lambert%27s_problem"
],
[]
] |
|
1j07ti
|
how does losing an eye lead to lack of depth perception? and to what extent does one face it?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1j07ti/eli5_how_does_losing_an_eye_lead_to_lack_of_depth/
|
{
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"text": [
"Hold up a finger in front of your face about 6 inches away. Next, alternate closing one eye (keep each eye open for about a second). You should see your finger sort of jump from side to side.\n\nIf your finger is centered on your case, the finger is a little to the right of your left eye and a little to the left of your right eye. This makes it seem like your finger is in two difference places. Your brain is pretty awesome. It gets the different signals from your two eyes and then assumes that the two separate fingers are the *same* finger and then makes a guess about how far away the finger is. \n\nIf the finger is very close to your face there will be a big jump in apparent positions. If the object is very far away (e.g. the moon) the object won't jump at all. \n\nSo when a person loses an eye, their brain only has 1 perspective per object. As a result, the brain can't make guesses about how far away something is.",
"The perception of depth is created using two sorts of visual cues, monocular and binocular. Monocular cues are well known to artists. Artists can give depth to two-dimensional drawings because they rely on the same sort of visual cues that we use when we look at a relatively-flat image as projected onto one eye.\n\nJust a few examples of monocular cues, with recent imgur pics:\n\nTexture gradient - when there is a texture or pattern to objects in the environment, the further away they are the more \"dense\" or small the texture seems to become. See, for example, the flowers in this picture: _URL_0_; or the cobbles in this road (ignoring the godforsaken Bieber fans): _URL_3_\n\nRelative size - objects that are further away tend to appear smaller. E.g., _URL_1_\n\nLinear perspective - As things get further away from us, parallel lines seem to converge into the distance. A great artist's trick is to draw a dot on your page and use a ruler to make sure all parallel lines are angled so that they are aimed at that dot. E.g., the trees lining the border in this US-Canada border image: _URL_2_\n\nThose are just a few of the ways that we can see depth without necessarily needing both eyes.\n\nBinocular cues, on the other hand, require both eyes and are what give us the greatest sense of three-dimensional depth. They work because your eyes are not in the same spot on your face. Because one eye is a few inches away from the other, they are taking in visual field that is angled a little differently from one another and so the image you see with your right eye is slightly different from your left eye.\n\nIf you've ever held up your hand in front of your face and tried closing your left eye, then switching to closing your right eye, then going back and forth to watch the image move, that's what I'm talking about. (And if you haven't done that, then dude, do it. Just don't smoke a joint first or you might not be able to stop doing it.)\n\nSo how does this translate into a three-dimensional image in our heads with depth? Well, our brain does some awesome and super-rapid math and uses the slight differences in images, combined with info about the angles at which our eyes are taking in the image, to make a single, unified image in 3d.\n\nLosing one eyes means we lose that binocular ability, and the rich, fully 3d perception of our reality. But it doesn't mean we lose our depth perception altogether, because our brain has a lot of ways to use monocular cues to figure out distances and such.\n\nTL;DR - Our brains are awesome; we use fancy math and angles to make 3d images with two eyes but also have tricks to see depth and distance with one eye. \n\n",
"I had a lensectomy when I was a month or so old. I have had sight in only one eye for essentially my whole life. In terms of depth perception it is difficult to explain what it looks like, or how I 'don't' have it as i have never had anything to compare it to. Also, as i have had it my whole life I can gauge how far away things are through experience, but not perceive a '3D' image as is able with two working eyes."
]
}
|
[] |
[] |
[
[],
[
"http://i.imgur.com/2w4YzsM.png",
"http://i.imgur.com/34d9oID.jpg",
"http://i.imgur.com/SKQlylQ.jpg",
"http://i.imgur.com/se4vr6d.jpg"
],
[]
] |
||
2bjkdq
|
what is cloudflare's ddos protection is doing?(see picture)
|
_URL_0_
I'm always intrigued by what it's doing behind the scenes.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2bjkdq/eli5_what_is_cloudflares_ddos_protection_is/
|
{
"a_id": [
"cj5zm81",
"cjm2uux"
],
"score": [
3,
2
],
"text": [
"The DDoS protection ensures that there are not a lot of connection requests coming from the same place. If there were, it would ignore them so that they didn't hinder the operation of the site. Thats the idea behind it at least. Having used cloudflare on a site before, it didn't necessarily always work as advertised",
"Checks that your browser uses javascript, most DDOS attacks dont \"read javascript\" so they cant continue."
]
}
|
[] |
[
"http://i.imgur.com/nKV5MnM.png"
] |
[
[],
[]
] |
|
3jobgj
|
why do smoke detectors require batteries, when they are plugged into the wall?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3jobgj/eli5_why_do_smoke_detectors_require_batteries/
|
{
"a_id": [
"cuqxysq",
"cuqy113",
"cuqy7cy"
],
"score": [
18,
2,
3
],
"text": [
"Smoke detectors don't get power from the wall. In cases of fire or other situations where you would really want your smoke detector to work, power outages are common. The fire could spread in between your fuse box and the smoke detector and cut off power to it, so it uses a battery.",
"You want them to keep working if the fire damages the wiring and the mains power fails, or just if there's a fire during a power cut.",
"In Australia it is now illegal to install smoke detectors that run purely on batteries. All smoke detectors must be wired to the main electricity supply AND have a backup battery in case of power outages. Having said that, it's amazing how many people don't have legal smoke detectors. Many people don't even have smoke detectors installed. You'd think in this country people would have more sense."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
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