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8miprv | how are copywrite laws viewed internationally? can a country choose not to acknowledge them and grant their own patents? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8miprv/eli5_how_are_copywrite_laws_viewed/ | {
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" > How are copywrite laws viewed internationally? Can a country choose not to acknowledge them and grant their own patents?\n\nYes. They could just not recognize it. Really it is that simple. However there are some international organizations trying to regulate this, but it only really works for nations who signed up to be regulated internationally (think first world nations)\n\nOf course any country could choose not to recognize or enforce any others rights (common in poorer countries in Asia and Africa), but there may be consequences to a country who does not recognize intellectual property rights of another country.\n\nRemember the Trans-Pacific Partnership (TPP) that was everywhere for a couple years but out of the news now? Well a major aspect of it was to get asian countries to respect US intellectual property rights, because often they just ignore them"
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66jgxg | how long can a country go with a budget deficit? | I get that a deficit can be beneficial in the short term to stimulate growth. But how long is too long before it needs to be eliminated? Can it go on indefinitely? Will our children end up paying for our overspending? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/66jgxg/eli5_how_long_can_a_country_go_with_a_budget/ | {
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"In theory, as long as their economy is still growing and the deficit isn't too large, it could continue forever.\n\nThe size of governmental debt is generally considered relative to GDP in order to evaluate its magnitude, and some countries have maintained debts in the 60-100% of GDP level for decades without problems. If a country's GDP grows by 3% a year and the country is comfortable maintaining a debt of 100% of GDP, then they could run a budget deficit of up to 3% of GDP without an issue. They could keep that up for as long as their country continued to grow, and it most likely wouldn't cause them any problems.",
"There's not a solid answer to your question. It depends on how big the deficit is, how big any debt or surplus is, how much the country's economy is growing or shrinking, how the payments that lead to that deficit are structured. The answer is anywhere from \"immediate crisis\" to \"forever\" depending on the variables at play. \n\nAll the word deficit tells us, is that you have spent more than you have made in a given time frame. Note also that deficit and debt are two different things, and also that it is not a goal of a nation, generally, to be debt free. ",
"Forever.\n\nImagine you had a job where you were guaranteed a 5% raise every year, no matter what. You could budget each year with a 3%-4% deficit, knowing your raise from that next year would cover it.\n\nThat's essentially what responsible deficit spending is, using the growth from next year to pay for things right now."
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6m8olj | - why are my fingers all not all independent from one another? | For example when you retract your pointer finger and pinky finger, you can't keep the middle finger and ring finger straight while fully folding your pinky finger in. Or in general you can't straighten one finger out completely while the rest if your first gets are in besides maybe your pointer finger and thumb. I hope this made sense! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6m8olj/eli5_why_are_my_fingers_all_not_all_independent/ | {
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"text": [
"The Tendons in the hand are all connected, if you bend one finger the tendon will pull the next slighty, [check this](_URL_0_)",
"Or for a little more gory explanation [watch this](_URL_0_) (probably nsfw)",
"Some of it is practice - I play stringed instruments and piano and can move every finger independently (and totally freak out non-instrumentalist friends!)\n\nSome of it is biology, ESPECIALLY when talking about the ring and pinky fingers. Those two fingers don't have their own tendons - there's one tendon that operates both fingers, which makes it really difficult to create independent motion. The tendons that control your finger are also controlled by muscles that are surprisingly hard up your arm."
]
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"https://youtu.be/9V1ZzAiB1rY"
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6qy43e | saw an article stating that earth will warm by 2 degrees by the end of the century, what exactly does this mean? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6qy43e/eli5saw_an_article_stating_that_earth_will_warm/ | {
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"The last 400,000 years have consisted of short interglacials (10,000 to 30,000 years) about as warm as the present alternated with much longer (70,000 to 90,000 years) glacials substantially colder than present. \n\nWe are currently in an Interglacial Period that started around 11700 years ago. The warmest period (Holocene Climate Optimum) was around 9k-5k years ago after that it cooled until about 2k years ago, then warmed up again until the Little Ice Age (1250AD-1850AD). Since then things have been warming up again."
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3682qx | how do video game developers (pc specifically) manage to develop games and ensure whether they'll be up to par on graphics standards/consumer hardware by the time the final product is ready to ship? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3682qx/eli5_how_do_video_game_developers_pc_specifically/ | {
"a_id": [
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"They either build for current cutting edge, or they build so that even current cutting edge can only manage to do medium quality.",
"Generally these days they build super high quality assets and scale them down to their target hardware. On pc of course you can have different levels of detail and on consoles usually optimize like crazy for whatever they can get away with while having a playable frame rate.\n\n It's important to note that top of the line pc rigs are already much much more powerful than console hardware and even more powerful than what 99% of people probably have in their computers so if your making a game on that type of hardware you are already ahead of the curve. It's also not hard to look at some hardware road maps to figure out where things are heading most companies have their hardware planned out years in advance. Some developers go as far to actually work with the gpu makers to push their games as far as reasonably possible.\n\nThat said few games are actually using the very latest current standards. It takes years to make high end AA / AAA quality games so your always dealing with sort of a delay before something new is being done for it to actually start showing up in games later to the consumer though you never notice because obvious unless you go to or pay attention to things like GGC(game developers conference) then you'd be pretty clueless on the latest advancements in game rendering.\n"
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7y74af | why do opposite poles of a magnet attract while the same ones repel each other? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7y74af/eli5_why_do_opposite_poles_of_a_magnet_attract/ | {
"a_id": [
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"text": [
"Electromagnetism, like gravity, is one of the fundamental forces of the universe. It \"just happens\" and there's not really much more to say about it.",
"Like someone else said in the comments, it pretty much juch happens, like with gravity. We're not really sure why, but we can describe it pretty detailed.\n\nOne way to visualize it, is like permanent jigsaw puzzle pieces - the pieces with \"bulges\" cant be connected with other bulges, neither can \"hole\"-pieces be connected with another hole. THey can connect with eachother though"
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7366kt | what prevents the wing of a plane from breaking mid air, under the pressure of wind/air? they seem so wobbly and unstable during takeoff... | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7366kt/eli5_what_prevents_the_wing_of_a_plane_from/ | {
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"The wings are capable of flexing quite a bit before they fail. This video shows engineers testing to failure, and you can see how far the wing can bend before it fails (catastrophically). The wing makes it to 150% of design load, which means that the engineers figured out how strong the wing had to be to perform safely, then included significant safety margins, and the wings as built far surpassed even those goals.\n\n_URL_0_\n\nHere's an image of a 787 wing test:\n_URL_1_\n\n",
"They are built to be very strong while maintaining the lightness to fly, and a bit of bending isn't a big deal.\n\nYou can tell how strong they are when they're just sitting on the ground - what other structures can you think of that can just stick out like that, 50-100ft, so thin without any support? (And heavy engines hanging off them to boot, along with fuel inside them).\n\nIn flight, the roles are reversed, and the wings are basically holding up the fuselage."
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"https://www.wired.com/images_blogs/autopia/2010/03/index1.jpg"
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200epv | in this advance of information technology, why we still rely solely on blackbox? | Remember when air france crash in atlantic in 2009 took years just to find the blackbox, Rely solely on blackbox make aircraft crash investigation become slow and drag on. If flight data could be transmitted in realtime to ground based control center, we would know the cause of accident in week instead of years. This is 2014. In last couple of years, we've already seen relatively cheap high speed internet services on airplane, then why we don't just use that to telemetry all of the flight data to ground based control center like NASA did? I believe it only use a small fraction of bandwidth.
I'm not thinking of replacing the blackbox by removing it completely, but use new technology to enhance the function rather than still solely depends on it
EDIT: Grammar | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/200epv/eli5_in_this_advance_of_information_technology/ | {
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"We don't rely solely on the black box. It is, as you suggest, a last resort.\n\nModern aircraft broadcast their position, elevation, heading, and air speed almost continuously, and this information is made available in real-time (europe) or nearly so (US).\n\nUnfortunately, in a situation where any of this is needed, is one where things have gone horribly wrong. In this case, the black box (which is actually hi-viz orange) may be useful or necessary to tie together many other pieces of information surrounding the incident.\n\nEven if we had complete, real-time data (as above) on every accident, the \"what\" data does not tell us \"why\". The \"why\" is the purpose of the long NTSB investigations, and would you really trust a report issued before all possible sources of data were collected?"
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76soxd | how companies track your browsing history. | For some background info, I'm at Uni and I was browsing through some products on my phone in my room. I went to the Computer lab and logged in. I found the same products i was looking at. Nothing NSFW i was just wondering how exactly they do that. I was on two different accounts. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/76soxd/eli5_how_companies_track_your_browsing_history/ | {
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"The more relevant an ad is, the more likely you are to click on it. Relevance and high quality clicks are encouraged and prioritized by ad networks like Google and Facebook, and result in cheaper costs to the advertiser and a higher likelihood of the user completing a specified action on the website (called a conversion) like a purchase or a form completion. \n\nAdvertising networks and e-commerce platforms provide tracking codes to advertisers to install on our clients' websites. This allows me to track actions like a website session, pages visited, actions completed on the website (like an item added to a cart, or an abandoned cart), etc. When you visit the website, tracking data is added to your web browser or associated with your account if you're logged in. Based on your activity on the website, which is anonymously shared with my advertising account, I can then show you, an interested user, ads relevant to what you were looking at. \n\nIn terms of cross-device tracking, all that data is gathered based on the accounts you're using. If you're logged into Google Chrome on your phone and look at an item on Amazon, that data is logged and associated with you (again, totally anonymously to me). Based on that, I can then set my ads up to show you similar items on other devices where you're logged in with that account. \n\nI wouldn't be able to say specifically how that happened to you in your example, but essentially it's you and your actions on both devices being associated with each other through whatever service, so the advertiser can hit you with ads. "
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a00lcz | how does light slowing down in different medium (like water) not affect time? | I read yesterday that very high gravity can bend light making that path it has to travel longer, and therefore time has to slow down to compensate.
So why does light slowing in water not have an affect on time? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a00lcz/eli5_how_does_light_slowing_down_in_different/ | {
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"The speed of light remains constant. But it is bounced around more in a denser medium, making it's effective speed lower. \n\nIt's the difference between running straight across a field versus running in a zig zag. You are running at the same speed, but you are effectively covering less distance."
]
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bkht4e | what allows us to think? i know that we do physical activities such as move and talk because the brain sends electrical impulses (or something like that) to your muscles. but what allows us to think in our heads? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bkht4e/eli5_what_allows_us_to_think_i_know_that_we_do/ | {
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"Language helps a lot. Language is like the device driver of the brain. It helps think abstract thought, memory and developing a self. If also creates an inner voice.\n\nIf a person fails to learn language when they are young because they are born deaf or other reasons, they will fail to develop an inner voice and they will be significantly mentally handicapped until they learn language. Even when they do they will still have negative effects since they didn't learn language until later in life.\n\nIf someone is born completely deaf and only learns a spoken language and not sign they are not much better off than people who don't learn a language. We think it is because the spoken language is too abstract to their brain. They fail to develop an inner voice.",
"It's called consciousness and it is still a mystery but there are people that study it trying to find answers."
]
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24fq6y | cell phone cloning | What exactly is done to "clone" a cell phone and what is the use of doing so? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/24fq6y/eli5_cell_phone_cloning/ | {
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"The What\n===========\n\nYou used to be able to drive up to the back of a cellphone store and grab their trash which would have tons of printed out orders with ESN numbers (codes that allow your phone to speak on the network) and phone number pairs. You could also order \"chipped\" phones which were modified phones which allowed their EEPROM (think really small disk drive) to be reprogrammed with a new ESN and phone number usually using specialized software and a data-link cable (think USB.) Some modifications allowed you to rotate through up to 50 different pairs using only the controls on the phone's keypad.\n\nIn modern phones I think it just means copying the SIM card.\n\nThe Why\n=========\n\nOne reason is to make free calls. I think this motivation was more popular in the 90's due to the expense of cell phones and cell service at the time.\n\nAnother is anonymity. You could be [tracked/triangulated](_URL_0_) eventually but you presumably wouldn't re-use the same stolen credentials for an extended period of time.\n\nThe technique is also useful in situations where you need to scam a victim but one barrier to pulling off the scam is phone call verification. Common with credit card companies etc."
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b18uuw | why do most shows use twins for their young, young characters? | For example, the Olsen twins shared the role of Michelle on Full House; I'm pretty sure the Sprouse twins shared the role of Ben on FRIENDS; twins shared the role of Manny (the youngest brother) in the OG Diary of the Wimpy Kid trilogy.
I've always wondered why movie and TV companies do this. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b18uuw/eli5_why_do_most_shows_use_twins_for_their_young/ | {
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"text": [
"Child labor laws - time restrictions on working hours for child actors. 2 kids in one part gets around this ",
"There are strict rules on the amount of time a child can work for. You would only be able to film for a short time each day. Having two children doubles the hours you can get on set for that character, making better use of the equipment and other people."
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13wzox | why is there a revival of feminism nowadays? | Has anything happened in particular that would explain this? For some reason everywhere I go people are discussing gender. I don't even know what most of the arguments are, and what it's all about, but from my perspective everything seemed to be...fine. And then all that. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/13wzox/eli5_why_is_there_a_revival_of_feminism_nowadays/ | {
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"text": [
"How old are you? \n\nI don't remember feminism ever going away ever since it became part of my consciousness in the 90s with riot grrl music. ",
"You're probably either just noticing it, or being exposed to it more. Feminism has been alive and well for decades. It's getting a lot more outspoken as it attempts to criticize other movements and subcultures (skeptics, gamers, science, etc.) that have been free from such criticism in the past, though. Maybe that's why - it's just intruding more into your field of view/experience.",
"It's become much more common on the internet in the last few years. The main reason is that social media (Facebook, Twitter, Tumblr, etc) has made it easier for like-minded people to meet each other and share ideas. This has led to the emergence of the \"social justice\" internet culture. \n\nUnfortunately, like-minded people tend to radicalize in the absence of contrary views (which happens a lot in online communities since it's very easy to ban/block people you don't like). This has lead to the emergence of [SRS](_URL_0_)-style lunatics, who are the most vocal feminists on the internet and the most likely to invade other forums, even though they're not representative of feminism as a whole. "
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43hrij | what happens to the ph scale is something more acidic than 0? | So let's take sulfuric acid (battery acid), which is pretty much at 0 pH which means it has a 10,000,000:1 ratio. But one day scientists discover an extremely strong acid that has a ratio of 100,000,000:1. Would that mean that this acid has a -1 pH, or would it still be expressed as 0? If it's expressed as 0, then wouldn't the pH system be kinda silly for very strong acids? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/43hrij/eli5_what_happens_to_the_ph_scale_is_something/ | {
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"text": [
"The scale goes below 0 (and above 14, for that matter)...\n\nIt's just a scale of measurement, like Celsius or Farenheit for temperature, and you set \"0\" somewhere convenient, not necessarily at the lowest possible point (although some scales, like Kelvin for temperature, do have a fixed 0 limit that are as low as physically possible)\n\nFluoroantimonic acid has a pH of something like -18 to -25",
"You simply go into the negative numbers. 0 to 14 is the range normally given, in part because pH is hard to measure at the extremes (which can also go over 14), but [one example](_URL_0_) would be a 37% by mass solution of HCl, with pH of -1.1 or so."
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2l7c2k | why don't people seeking physician-assisted suicide just overdose on their regularly prescribed pain medication? | If physicians are legally allowed to prescribe pain medication that could potentially be abused, couldn't people seeking euthanasia simply be told the amount needed to overdose and then do it themselves? Of course this wouldn't work for people who are incapacitated to the point where they could not administer the drugs themselves, but couldn't this be a simple loophole to the PAS legal dilemma? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2l7c2k/eli5_why_dont_people_seeking_physicianassisted/ | {
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"I think you're missing the point. Any one can kill themselves any number of ways. The only limit to the number of ways you can off yourself is your imagination. What is up for debate here is whether a person has the right to kill themselves by being assisted by a physician. A physician can give a cocktail of drugs that will make the suicide both quick and painless, while providing the oversight that makes sure both of those conditions happen. ",
" > Why don't people seeking physician-assisted suicide just overdose on their regularly prescribed pain medication?\n\nBecause it might not kill you, or if it does, it could be the most gruesome, painful death you don't want to imagine. And if it doesn't, it could leave you in a worse state than you were trying to escape."
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3ttvzy | why can some overweight people lose weight with no excess skin, but others skin doesnt go away? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3ttvzy/eli5_why_can_some_overweight_people_lose_weight/ | {
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"It depends on how fast the weight loss is, how long the person was overweight, the method of weight loss, and then genetics. If someone was seriously overweight for 30 years before finally getting lipo, they'll have excess skin. If someone was seriously overweight for a short period of time but lost weight through dieting and exercise (a more long term solution versus lipo) then that person will probably not have excess skin. Also as height mentioned, age is a factor (edit) ",
"The skin can 'bounce back' if its not over stretched, or not stretched for too long. \n\nMany obese people are so fat they overstretched their skin, or were fat for so long, the elasticity was lost.",
"Imagine your skin like it's an elastic band. If you stretch an elastic band a little bit, and then release it, it goes back to (mostly) its original size and shape (this is like a small amount of weight gain). If you stretch it as much as you can, and keep it stretched and pulling for a long time, when you let go the elastic will seem bigger and looser than when you started (this is like bigger weight gain/loss).\n\nHave you ever noticed how some elastic bands feel stretchier than others? Skin is like this, too. Depending on how much collagen and elastin skin has, it's either like a the kind of rubber band that goes back to its original shape, or remains stretched out. ",
"In general, as others here have mentioned, there is a certain amount of elasticity to the skin and it can be stretched to a certain degree. But if you stretch the skin out and hold it for a long period of time this will induce cellular mitosis, which is fancy for cell replication, or even more simply put, the cells start copying themselves and you actually grow new skin. Another example of this is people with gauges or plugs in their ears where they make the hole really big. They aren't just stretching out their skin, they're actually growing new skin. Also, men who were circumcised at birth but later as adults want a foreskin can go through a process usually referred to as restoration where they actually grow a new foreskin by stretching out the existing skin around the shaft of their penis, in the direction of their penis. Over time, the skin will extend past the glans and the man will have new foreskin (it should be noted, however, that it won't be exactly like the original because there are certain specialized cells at the tip of the foreskin that once removed and discarded can't be regrown). The same is true for people who have been overweight. If they were really overweight for a long period of time then their skin would have been stretched out long enough for them to actually grow new skin. Then when they lose the weight the new skin they've grown doesn't disappear. But if they were only a little overweight the skin wouldn't have been stretched out enough to induce cellular mitosis not matter how long they were overweight, or if they had been a lot overweight but only for a short period of time it wouldn't have been enough time to grow new skin either.",
"It depends on how much fat they have / how much the skin stretches out, and how long they've had it. If they've had it for like, say, 50 years the skin will just stay there without surgery but if you're 15 and lose it there'll be less.",
"Follow-up question: what are the options, other than surgery, to avoid this? Can one lose weight and minimise excess flappy skin?",
"I need to lose about a 100 pounds and while I feel confident that I will one day succeed, it sucks knowing I'll need surgery afterwards."
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c6uss0 | - why does the air feel “lighter” when it seems like it’s about to storm? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/c6uss0/eli5_why_does_the_air_feel_lighter_when_it_seems/ | {
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"The \"trigger\" for many storms is a warm front moving into an area. Warmer air is less dense and has a lower pressure, so it is \"lighter\".",
"If there is a thunderstorm brewing you can sometimes \"feel\" the \"electricity\" in the air and your hair can rise. This is because the thunder clouds are building up a tremendous amount of negative charge in the clouds and that charge starts to build up a positive charge in the ground. This creates a difference in potential which is ultimately what leads to air to ground thunderstrikes."
]
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7kni74 | why does xanax make people sleep for so long? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7kni74/eli5_why_does_xanax_make_people_sleep_for_so_long/ | {
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"text": [
"Xanax and other \"benzodiazepine\" group drugs inhibit your brain's GABA neurotransmitters which is related to \"alertness\" state. \n\nThese drugs prevent alertness and hence can make people relaxed until your body gets rid of it slowly.\n\n"
]
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3g7tny | why do workout instructors always remind everyone to keep breathing and why is it my instinct to hold my breath when i'm working out? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3g7tny/eli5_why_do_workout_instructors_always_remind/ | {
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"I'm not a fitness guru by any means, but when you lift you tighten muscles and push hard. \n\nPeople might have to train themselves to not strain the diaphragm as well (the muscle that pushes your lungs). \n\nSort of like training your pinky not to move when you flex your ring finger. ",
"You hold your breath to buttress your core (abs/spinal flexors) and you generally want to hold it through the entire work part of the exercise. Some people forget to breath and pass out. The instructor is just reminding you to breath on the parts that are easy so you have the air to exert yourself again on the next rep. \n\nI personally think it's a little silly but then I can barely deadlift 400lbs unlike those guys who are pulling 800 and tell you to breathe, so I'd go with them. ",
"Focusing on breathing is also a way to relax and center yourself, or even distract yourself from the pain of your muscles are getting tired and trying to convince you to quit. ",
"When you hold your breath when lifting a weight, you increase intra abdominal pressure. The more weight you lift, the more likely you will do this. This creates stability, like a tire that you will blow up.\nIt comes with risk, as in, it may increase the overall pressure in your body (blood pressure etc., you even may shit yourself ;) ), and it uses way more muscles than the one that you are training (because it is a strategy that comes in handy when you want to lift very heavy objects.\n",
"I have no idea why your instinct is to hold your breath. However, with breathing this is due to oxygen. Your muscles need oxygen to work effectively and when you don't breath you increase your chance of injury.",
"Everyone uses filled lungs to support their body, like a full air mattress that you can't bend. That might help you keep your posture when exercising, for a few seconds, but you have to breathe in new air eventually.",
"I think its important to mention that is your insitnct to hold your breath because, natrually, nobody is squatting 225 lbs for 10 reps. In a natrual setting we lift things once and holding your breath for that short amount of time will not disrupt your bodily functions. So from a biological standpoint, its worth it to throw in extra stability in exhange for breathing. We're taught breathing methods in weight training because weight training is different than the kind of stresses we generally evolved for"
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adkmjw | what is physically happening when someone’s vision goes black? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/adkmjw/eli5_what_is_physically_happening_when_someones/ | {
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"It has to do with your brains ability to process the info that your eyes are taking in. When you stand up to fast the blood rushes out of your brain and it has some temporary trouble processing all of the visual info it is being given."
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20eu6t | how do people manage to "not let their emotions get to them"? what does it mean? | Because it's not as if there is an off/on switch for emotions? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/20eu6t/eli5_how_do_people_manage_to_not_let_their/ | {
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"They feel emotions, but don't let them impact their decisions. For example, if I get angry with you, but don't punch you in the face. It's not about turning off emotions, it's about having self-control.",
"It means that you have an extra step between thinking and acting. It's like another level of consciousness. Although frankly, it's the level all adults should be at.",
"It's not about turning off emotion but rather using self-control to respond in a manner which you won't regret when your emotions cool off. Even when angry, some people can still piece together a response that doesn't involve yelling and/or swinging limbs. And if this is too difficult, knowing yourself and your emotions will help you to know when to remove yourself from a situation before it grows out of hand.",
"This is anecdotal, but it might give you an idea of what it means:\n\nMy SO and SO's Mom do not have the best relationship. It goes between amiable and toxic, depending on the day. They are working on it, and I think things will get better in the future, but the first few years we were going out, SO-Mom was not pleased with me.\n\nSO-Mom would often show up to SO's apartment and start arguments - shouting, accusing us of all kinds of evil things, accusing me of various criminal activities, etc. etc.\n\nDuring those moments, SO usually would be livid, screaming and shouting right back. This is an *emotional* response.\n\nI usually sat back and let SO-Mom scream and shout, and would try as best as I could to mediate the situation. *Internally* I wanted to do what SO was doing. *Externally* I tried to handle the situation as calmly as possible.\n\nThat's generally what 'don't let your emotions get to you' means - its a skill, something that has to be learned and practiced over time, to be able to suppress the physical and mental reactions that come from being angry, sad, happy, frustrated, etc., and ensure that your actual behavior remains controlled and cool.\n\nI learned most of that growing up and watching my emotional mum shout at my very logical dad. Their relationship today is amazing, but I think its largely because in the moment, my dad was able to stay collected and not let the situation escalate. I'm still working on it, I still lose my temper from time to time, but I do my best to stay in control whenever possible.\n\nI often refer to military training as an example - what they are really training you to do is how to be shot at and not lose your shit. they are training you to operate on a physical and mental level where you are above your emotional response to a situation.\n\n**But why would you want to do this?**\n\nI find that in a situation where emotions are high, the more your behavior reflects your emotions, the worse the situation becomes.\n\nStaying calm, collected, and attempting to resolve the situation as simply as possible almost always will result in a better long-term solution.\n\n**But what about happy moments?!**\n\nWell, happiness is a wonderful thing, but that doesn't mean you should lose your head. My bonus check was a very happy moment, but I didn't blow it all in the heat of the moment. I saved about 75% of it, which ended up being handy when the IRS discovered an old contract check I didn't do my taxes on properly, and asked me to cut a check for the taxes I missed.\n\nIt's not easy to do, but IMHO its always the better option. You can have emotions internally that you can let out at a time when its healthy to do so, or in a way that is healthy, but responding in the moment with emotions can land you into trouble.",
"A lot of the times it can just be as simple as taking a mental step back out of the situation and not letting what has been said or done effect you. I work in a kitchen where I am constantly yelled at, some people will turn around and yell right back (they usually get fired) but the rest of us just apologize regardless of fault and internalize it then at the end of the night go out for a drink and vent or something. ",
"It is about acting to your benefit *despite* having an emotional reaction.\n\nLet's say you robbed a bank, and the police were interrogating you. They might say some about how anyone who would raise a bank robber must be a terrible mother. You could angrily defend your mother, and in the process admit to being a bank robber. Or, despite being angry, you control your emotions, and make the police find some other way to prove their case."
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1fpvq5 | how does common law system works? | As a roman system student, i just can't get the idea of common law and how you not have it all codified.
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1fpvq5/eli5_how_does_common_law_system_works/ | {
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"dictionary definition: The system of laws originated and developed in England and based on court decisions, on the doctrines implicit in those decisions, and on customs and usages rather than on codified written laws.\n\nhowever in plain english, and in more detail, for example:\n\n(I am currently studying Australian politics, so ill use a case from there) in the case of Mabo vs Queensland no.2 the case initially arose from the Queensland government seizing Murray island from the indigenous peoples. Native citizen Eddie Mabo challenged this to the Australian high court, led by Chief justice Anthony Mason. the court decided in his favor that the island belongs to the islanders, and was a landmark case when it comes to indigenous rights. the reason why this case was a common law case, was because of the precedent (decision that is relevant in the future) that it set. in a future case, if indigenous land rights are violated, by some authority, the case can be used (as long as it is similar) to support the plaintiffs case.\n\ncommon law initiated in England in the middle ages, where a group of elite judges would meet and decide which cases would take precedent when it comes to future cases. Nowadays, it is a much more flexible process where it is up to the plaintiff on their own volition to find a case where a precedent can be used. \n\n**TL;DR** where previous cases can be used in order to support a plaintiff's/defense's side when it comes to a supporting their case",
"The idea (at least back in the day) was that \"Common law\" was simply in existence. It was the law. It always has been the law and it always will be the law, but judges (through the cases brought before them) would 'uncover' bits of law and explain it as it applied to the cases before them. Based on these explanations later cases would have a better understanding of the law and it would be more certain.\n\nThe more modern view is that it is a judge made law which is applied consistently by judges in later cases and expanded into new areas by analogy. The judge is a *kind* of a lawmaker which allows the law to develop slowly (as problems are found with it) and consistently. \n\nThere are a few reasons for not codifying \n\n* Most of the time it worked. Judges, most of the time delivered decisions that the community agreed with, so there wasn't a need to change anything\n* When it didn't work, there might have only been one or two things that the community (and parliament) disagreed with. Why codify the whole thing, when you can just change the one or two bits you don't like? \n* There is also a sense that laws were only needed to correct behavior, if no case was brought, there was nothing wrong. thus there was no need to have all the laws in a big code so the common law system of only enlarging the law as little as possible on the case before you seemed to make sense. \n\n\n\n\n\nThese days *every* common law jurisdiction has some things codified, and a lot of common law is modified by statute. So it's not often that \"pure\" common law will apply. Here, for example, we have a Criminal Code which is exhaustive (like in Roman systems). But we also have a kind of torts legislation that modifies the old common law rules. It's so big that it's almost a code, but it doesn't re-state all those basic principles that we have left over from common law, just the specifics. \n\n\n**tl;dr** Pure common law is kinda lazy. We fix problems as they come up, rather than trying to think of everything that could come up and putting it in a code. \n"
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3zfkuq | how does triangulating a call work and how are police able to determine the location of a caller? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3zfkuq/eli5_how_does_triangulating_a_call_work_and_how/ | {
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"Mobile phone base stations often have multiple sectors - each sector will have an antenna or antennas that cover a certain direction. It's common to cover a 120º arc with a sector, using a three-sectored site to cover a full circle.\n\nBecause of this, you can then tell vaguely which direction someone's in when they made a call.\n\nAnother thing that comes in handy is the strength of the signal they were sending back to the base station - rather than putting the person anywhere in that 120º bit of land that could stretch several miles from the site, the signal strength will give you an idea how far away they are, although will still only allow you to narrow it down to that 120º arc. It's imprecise, but better than nothing.\n\nHowever, it is sometimes possible to find out the same thing from other adjacent cells. If Cell A tells me the caller is somewhere in a certain strip of land to its north, and Cell B gives me a strip of land to its west, you can combine the two areas, and your caller is likely to be where those two strips overlap.\n\nAgain, not precise. Buildings and general urban clutter can ruin the precision somewhat."
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1f1vr6 | why does food from restaurants taste so much better than food i make at home? | Even if it's something east like grilled vegetables, steak, or chicken food from take out and eat in places always taste better than the results in my own kitchen. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1f1vr6/eli5_why_does_food_from_restaurants_taste_so_much/ | {
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"Often because it has lots more salt in it than you'd use at home. Butter is used in lots of restaurant cooking, too, which also enhances flavours.",
"In addition to extra salts/seasoning/butter, consider a few other things:\n\n· Restaurants usually have a set menu, with meals that they make over and over again. Experienced cooks and chefs have plenty of practice making steaks, vegetables, etc. and have gotten very good at making them taste as good as possible.\n\n· Restaurants may have access to ingredients that aren't particulary easy to find in grocery stores. This is especially true given the previous point. Having a set menu means you'll likely use large amounts of only a few ingredients. One that comes to mind is Sysco's \"Liquid Butter Product\", used in some sauces and other places where a giant bottle of flowing butter would be helpful.\n\n· You may have heard the phrase, \"Presentation is everything\". Everything from the description on the menu to the plating (the way the food is displayed when it arrives at your table) can actually change how good you feel about the food you're eating. Next time you're at a restaurant, pay careful attention to the words they use to describe the menu items. You'll likely find heavy use of \"good sounding\" describing words, like \"fresh\", \"savoury\", and \"creamy\".\n\nRegarding the last point, here's [a great clip](_URL_0_) from Penn and Teller's \"Bullshit!\", where they use plenty of not-so-amazing ingredients to make so-called gourmet food. (contains somewhat NSFW language)\n\n**EDIT**: One more thing. There's a bakery near me that has a chemist for their head pastry chef. The results are mind-blowingly delicious, since she has a much deeper chemical understanding of flavour, and how to manipulate it. That said, large chain-style restaurants that control their own product distribution could easily employ similar methods, by making chemically-enhanced sauces and flavourings in a lab or factory, and shipping them to their locations.",
"Maybe you're not a great cook? Just kidding!",
"They spend a lot of time and money perfecting their recipes. A lot of the chefs also go to school to be good at what they do.",
"Because they have professionals preparing the food. They cook orders of magnitude more food than you ever will in your life, so it's inevitable that they will be better than you (e.g. knowledge, timing, temperature, ingedients, etc.) even with the exact same produce & ingredients.\n\nIt's a bit like asking why a carpenter makes a better set of shelves than you do when you potter around with tools on the weekend."
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a5wqxo | where does the brain generate its ‘current’ to send small electrical impulses to muscles etc...? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a5wqxo/eli5_where_does_the_brain_generate_its_current_to/ | {
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"There are pumps and gates in your cell membranes, which control the flow of ions. Ions are charged particles (positive or negative), so their movement creates a current and thus electrical impulses.\n\nOne example of a pump is the sodium-potassium pump. This pump exchanges 3 Na+ (soidum) ions for 2 K+ (potassium) ions, making the cell lose 1 positive ion each time. This makes the cell more and more negatively charged over time. This effect is slow-ish and mostly constant.\n\nNow we come to the gates. These have a “threshold”, like a plug in a broken dam holding back the water. Once the threshold limit is crossed, everything just bursts through.\n\nIn the sodium-potassium example, the sodium gate will open when the cell reaches a certain threshold of negative charge, which will instantly draw the sodium from outside the cell back into the cell to balance the concentration lost by the pump. This causes a massive shift of ions, creating an electrical impulse.\n\nThe electrical impulse can also trigger other gates in neighbouring cells to open, causing a “cascade” where the first signal spreads out and travels down the nerves to muscle cells.",
"Special proteins in the membranes of neurons create a difference in voltage by forcing specific types of ions (electrically charged particles) to one side. When a signal is sent, this voltage difference briefly \"flips\" in a chain reaction along the neuron as ions are allowed to pass through the membrane. This flow of ions generates a small electric current.",
"Positive little particles like to go to space full of negative little particles.\nThe Brain cells have the power to create a space full of positive particles (out of the cell) and a place with less positive particles (creating a negative space inside the cell). These spaces are separated by a wall called the cell membrane. When the cell is stimulated by something there are tiny doors throughout the wall that get open and allow the movement of positive particles to the inside of the cell creating an electric charge.",
"The cell is an oily bubble with an inside and outside. In nerve cells, there's a fat end with the fiddly bits of the cell, and a long tail extending from it (called an axon). There's basically salt water on both the inside and outside, but the inside has the bits that are the cell, and the outside is the bits outside the cell (like other cells).\n\nSalt water is water with salt. Salt is made up of a positively charged part and a negatively charged part. For example, table salt is Na (sodium), which has a positive charge, and Cl (chlorine) which has a negative charge. When dissolved in water, positive and negative bits move around separately.\n\nNerve cells have little pores made out of protein that poke through the fat bubble (cell membrane) so that they touch either side. These proteins act as little gates and push the positively charged bits from the inside to the outside. This means that there's a difference between inside and outside, with outside having more positive bits, and the inside having more negative bits -- kind of like the + and - ends of a battery. We call that difference an \"electrical potential\".\n\nAt some point, the main part of the cell sends a chemical signal that triggers the gates to open wide and let the positive charge back inside to mix with the negative again. That starts at the fat end of the cell and works its way down the tail bit -- and that's an impulse. When that happens, it knocks off neurotransmitters at the end of the cell and if they touch an adjacent nerve cell, that can trigger that adjacent cell to cut loose too. A whole bunch of these cells bunch together to form a nerve, and when they all fire off at once, we call that a nerve impulse, and you can use electrical equipment to follow the movement of the charge in the nerve.",
"Since you seem OK with the idea of charge, start with the difference between current (flowing or moving charge) and a charged particle ( a static or unmoving charge). Electricity in wires is flowing current, a charged particle is more like a magnet. The 'current' in your nerves comes from moving charged particles, not 'current' like the flow of electrons in a wire. Picture a chain reaction down a long line of magnets.\n\nBasically before firing, the nerve cell uses energy to move lots of particles with one charge - say, positive - outside the nerve and the negatives stay in. They want to flow back but can't yet, so it's energy stored like a battery.\n\nWhen the nerve fires, one end of the cell opens a gate that lets the charges return to where they wanted to be, which triggers the next gate which triggers the next and so on down the nerve. Happens fast but not electricity fast. (quick google search says 266 mph for nerves v. over 41,000 mph for electricity....)",
"In your body you have little power plant workers (ions) some of whom are more positive than others and others who are less positive or even negative! When there are more positive workers than negative workers in the power plant (neurons) the whole power plant begins to work and becomes a huge positive place to work. \n\nThey send some of this positivity to the power plants (neurons) nearby which then also become positive. It's contagious and soon all of the factories in a chain become positive which eventually gets electricity to the town (muscles, organs, etc.) and activates them. ",
"Think magnets. Tiny magnets. These tiny magnets want to get into the cell because the magnets want to meet stuff inside. And they're held out of nerves by little gates. Then, when the gates get opened somehow, the magnets flood into the nerves. When the magnets flood in, they cause other gates to open, and gates get opened all the way down to the bottom of the nerve. These then cause things to get shot out of the nerves at the bottom, kind of like balloons with weights, that then go and land on the next nerve cell. These then cause the gates in the next nerve to open, and the magnets start rushing in again. This happens until the balloons with weights reach where the signal is necessary. ",
"Cells use chemical energy, from things we eat, to push or pump the “positive” and “negative” (as in battery ends) halves of salt molecules to the opposite side of the cell’s skin. This builds up a charge on either side of the skin. \n\nWhen a switch called a receptor fires in the cell, usually triggered by other small chemicals called neurotransmitters, the pumps change shape, stop working, and the Charge snaps back across the skin.\n\nThen, other pumps get fired by that charge and the whole cell charges. "
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1nl7k1 | why doesn't batman kill the joker when the opportunity shows itself? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1nl7k1/eli5_why_doesnt_batman_kill_the_joker_when_the/ | {
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"Not sure if it's oath, but more like a moral code and he sticks to never killing anyone.",
"Because that contradicts Batman's philosophy on killing people. Bottom line is that he doesn't kill anyone. He just does enough to incapacitate them until he takes them in or the GCPD comes to aid.\n\n(I found this whilst interwebbing an answer for you)\n\nThe Joker and Batman are each trying to prove a point to society - and really to us, the readers. The Joker wants Batman to kill him because he perfectly embodies chaos and anarchy and wants to prove a point to everyone that people are basically more chaotic than orderly. This is why he is so scary: we are worried he may be right. If the Joker is right, then civilization is a ruse and we are all truly monsters inside. If the Joker can prove that Batman - the most orderly and logical and self-controlled of all of us - is a monster inside, then we are all monsters inside, and that is terrifying. The Joker is terrifying because we fear that we are like him deep down - that he is us. Batman is what we (any average person) could be at our absolute best, and the Joker is what we could be at our absolute worst. The Joker's claim is that we are all terrible deep down, and it is only the law and our misplaced sense of justice that keeps us in line. Since Batman isn't confined by the law, he is a perfect test case to try to get him to \"break.\" The Joker wants Batman to kill a person, any person, but knows that the only person Batman might ever even remotely consider killing would have to be a terrible monster, so is willing to do this himself and sacrifice himself to prove this macabre point. Batman needs to prove that it is not just laws that keep us in line, but basic human decency and our natural instinct NOT to kill. If Batman can prove this, then others will be inspired by his example (the citizens of Gotham, but again, also the readers), just as we are all inspired every day to keep civilization running smoothly and not descend into violence, anarchy, and chaos. This ability to be decent in the face of the horrors and temptations present all around us is humanity's superpower, the superpower of each of us. The struggle of Batman and the Joker is the internal struggle of each of us. But we are inspired by Batman's example, not the Joker's, because Batman always wins the argument, because he has not killed the Joker.",
"batman's parents were murdered in front of him as a kid. his life goal is to prevent criminals from killing people. would be hypocritical for him to kill criminals. batman never kills anyone in the comics. they always get knocked out and sent to jail. ",
"Because, in his mind, it wouldn't end with the Joker.\n\nHe snaps the Joker's neck and six months later he's shooting muggers dead in the street.",
"What is he without the hunt? *LIGHTNING*",
"Just for the record, In The Dark Knight Returns (Part 2 I think?), Batman kills the Joker. Snaps his fucking neck as the Joker just laughs... ",
"As a practical matter, Batman emerged at a time when comics books were aimed towards children, and there was a moral understanding (an later an explicit code) covering what comic books could depict. Murder and death were right out, often for both villains and heroes.\n\nThat's why the Joker robs banks with laughing gas instead of machine guns, and why just about all the older heroes rarely ever kill, and never intentionally. The whole personal code thing is to justify the anachronism. "
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39qgn4 | why do roundabouts on signs (uk) never join up and make a complete circle? | This may just be in Britain but all road signs containing a roundabout never join the roundabout into a complete circle, but leave a gap. This is really frustrating for some reason and I don't understand why they feel the need to do it! xD
Example: _URL_0_ | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/39qgn4/eli5_why_do_roundabouts_on_signs_uk_never_join_up/ | {
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"I've always thought its to help determine where you are and which turning is which. The gap is always between where you enter and the last exit, I just think its a way to look up and to see okay third and last exit, or second and straight ahead. Its to show that there are no more exits at a quick glance "
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jole8 | how movies theaters are allowed to discount tickets in the mornings, and how much money they actually make per ticket. | I had heard from a friend's brother when I was younger that movie theaters made nothing off of the tickets but took in 100% from concessions. That doesn't seem right to me though.
So, if they make nothing off tickets (or very little), how can they reduce the price by nearly 50%. Here, I went to a movie in the morning, and it was $6, but at night/after noon, it was around $12 I think. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/jole8/eli5_how_movies_theaters_are_allowed_to_discount/ | {
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"When you buy something, say a new computer, that merchandise has an expected life time (how long it will take to break or become obsolete). At airports this is generally why planes take off again as soon as they possibly can; it costs so much to buy a jet in the first place that in order to make any money back as profit the airline industries have to maximize the amount of money they can get within the planes expected lifetime.\n\nNow onto a movie theater. A theater needs to have a room, a projector, and a film. In general people tend to to only see movies at night, which leaves theaters with a bit of a problem. If they don't make the most of their investments before they need to be replaced, the company will lose money. However, hiring people to man the concession stand and ticket booth during mornings when there are barely any people in the theater will cost more money than it brings in.\n\nWhat most theaters do to still turn a profit on their investments during non-peak hours is they offer cheaper tickets in the hopes of attracting more customers.",
"When you buy something, say a new computer, that merchandise has an expected life time (how long it will take to break or become obsolete). At airports this is generally why planes take off again as soon as they possibly can; it costs so much to buy a jet in the first place that in order to make any money back as profit the airline industries have to maximize the amount of money they can get within the planes expected lifetime.\n\nNow onto a movie theater. A theater needs to have a room, a projector, and a film. In general people tend to to only see movies at night, which leaves theaters with a bit of a problem. If they don't make the most of their investments before they need to be replaced, the company will lose money. However, hiring people to man the concession stand and ticket booth during mornings when there are barely any people in the theater will cost more money than it brings in.\n\nWhat most theaters do to still turn a profit on their investments during non-peak hours is they offer cheaper tickets in the hopes of attracting more customers."
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29yefs | how was not allergic to penicillin when i was a young kid, but at 25 i am? | I had taken antibiotics that had Penicillin when I was a kid for ear-aches, but I am now 25, just recently had a tooth extraction, and had to take antibiotics that had Penicillin, and I broke out in a itchy rash. Why? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/29yefs/eli5how_was_not_allergic_to_penicillin_when_i_was/ | {
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"Allergies can be somewhat variable. People can become allergic to certain things that they've had repeated and/or prolonged exposure to. Conversely, people can lose allergies. I was quite allergic to cut grass when I was younger, however, I asked for a scratch test during my last physical (just out of curiosity), and apparently I no longer have any allergies..."
]
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u1xw6 | how do coupons work? | Does the seller (Walmart, Kroger, etc.) lose money/gain? Does the company that owns the product lose/gain money? Who gets the most profit?
Thanks in advance. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/u1xw6/eli5_how_do_coupons_work/ | {
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"There are vendor coupons, Wal-Mart would eat the cost on those, and manufacturer coupons, Wal-Mart get compensated from the manufacturer for those.\n\nMany times a vendor will \"double\" a manufacturer's coupon so they essentially split the difference. ",
"Coupons can make money in a couple of different ways.\n\nIf I had a coffee shop, you might come in and get a cheap coffee but then also buy a slice of cake to go with it. Overall, I'm still making money from you being there.\n\nYou might also have never been to my coffee shop, but find out that you really like my coffee, cake, atmosphere, cute girl serving, whatever, and start visiting regularly. Now you're a customer and you weren't before.\n\nIn other cases, I might have accidentally bought way too much coffee and my stockroom or warehouse is too full and the coffee's about to pass its use-by date. I can either throw it away or sell it for cheap. At least I get *something* if I sell it cheap. It also frees up some space in my stockroom for new stuff that people will want to buy.\n\nSometimes, products are so expensive that I can knock a bit off the price and still make money. Sometimes I can make no money, or even lose a little bit on that single purchase, because I know that the extra slice of cake you bought, or the fact that you'll come back in the future, will make it all worth while in the long run."
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dc105q | if kuru is spread through eating infected brain tissue, how did it first develop? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dc105q/eli5_if_kuru_is_spread_through_eating_infected/ | {
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"Basically a disease like that forms through mutation in patient zero, who dies either as a result or from other causes. In the cultures where kuru is prevalent it's often due to ritual cannibalism. People ate the infected patient zero's tissue and the disease spreads. Since kuru is not immediately debilitating and lethal, the people carrying the prion from when they ate the infected meat are able to pass it on when they die.\n\nAnd just reading into it now, apparently it has an incubation period of 10-50 years, explaining why people still seemed to contact it even though we now understand how it spreads. Aside from people living that are walking around with the disease already, a person who dies without ever showing symptoms could still spread it.",
"Patient 0 was most probably a very young infant with a genetic malformation either in his/her Prion protein or of the chaperone proteins that are normally in place to help misaligned proteins back into their 'proper' shape. I say the patient was probably extremely young because one, the disease is a death sentence, and two, the Fore people believed Kuru to be sorcery or witchcraft and would likely quickly kill and cannibalize the affected individual. It has also been suggested that the initial 'source' of Kuru was a stillborn with a mutation in his/her prion proteins due to the severity of the condition. Now the reason why we don't see this mutation anymore is due to the way Kuru affects people.\n\nIn Kuru the initial patient had miss folded prion proteins (Maybe due to genetic mutations), namely type PrP^(sc). PrP^(sc) differs from the normal PrP^(c) (Prion proteins that we all have that are needed for proper function of our nerve system) due to wrongful folding causing a massive increase in the amount of beta sheets, however, the amino acid strain remains the same (An easy way to picture this is by imagining a string and just laying it down in a different way, the string is the same, but if you tie it in a knot it suddenly has a different function). PrP^(sc), due to this structural change, is almost impervious to any form of degradation (destruction) and even promotes nearby PrP^(c) to change to PrP^(sc). As PrP^(sc) is almost indestructible it wouldn't be broken down by the stomach juices and would inevitably be taken up in the intestines, eventually starting a change reaction by now changing the PrP^(c) of those who ingested the contaminated meat. As PrP^(sc) is incapable of its normal function within the nerve system Kuru symptoms begin to form.\n\nBit of a long explanation for this sub but I hope its still informative. Dont hesitate to ask any additional questions!"
]
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[],
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7e5k23 | why do mood swings occur? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7e5k23/eli5_why_do_mood_swings_occur/ | {
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"Mood swings refer to a rapid change in mood. They can occur in women who suffer from PMS or people who suffer from more serious disorders such an major depression, bipolar disorder, ADHD, schizophrenia, or other mood disorders. They can also be caused by thyroid disorders. \n\nFrom my limited understanding on mood swings (I'm bipolar and have ADHD) there are neurotransmitters at play, one of them being serotonin. If a person has an abnormal amount of a neurotransmitter, this may result in a mood swing disorder (such as bipolar or ADHD). Serotonin is one such neurotransmitter which is involved in regulating our mood, sleep, and overall emotional state. \n\nNot eating or changes in your sleep patterns might alter your mood and therefore cause a swing as it would alter your serotonin levels and blood sugar. \n\nSomeone more well-versed will likely come along. \n "
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ftj876 | how do zoo owners hang out around tigers and lions? why don’t these animals tear them to shreds? does it mean that wild animals can be domesticated? | Edit: I watched Tiger King on Netflix and apart from all the craziness in that documentary, I was also shocked to see how comfortable these people were around Lions and Tigers and vice versa. How does this happen?! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ftj876/eli5_how_do_zoo_owners_hang_out_around_tigers_and/ | {
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"Wild animals can be *tamed*, but that is not the same thing as domestication. Domestication is a multi-generational process where an organism *evolves* to become more adapted to human use. We bred dogs to be friendly and to fetch stuff. We bred cattle to be calm and let us put harnesses on them so they could pull plows. This takes place over generations. Eventually the animals evolved into entirely new species or subspecies, genetically distinct from the wild animals populations they came from.\n\nWith zoo animals, they're not domesticated. They're wild animals that are held in captivity, which isn't the same thing. But any animal can learn to be calm around humans, to see humans as non-threatening, and to appreciate humans that are trying to help them (like by bringing them food). The tigers and lions at the zoo are tame, not domesticated. It would take a couple hundred generations at least for them to evolve into domesticated animals.",
"I'm guessing you've seen Dean Schneider or someone who kinda does what he does. In most normal zoo's the owners don't go near these animals, they just send staff to feed them.\nNow in sanctuaries and mainly places where animals are saved, they are sort of already used to humans, but they are still wild animals.\nA wild animal will remain a wild animal no matter what, you can't turn your back on them because one day they might get your neck.",
"No legitimate zookeeper will “hang around” with the big cats. Most AZA accredited zoos have facilities designed so that you never have to be in the same room with Lions or Tigers for feeding or other chores. \n\nHowever sometimes keepers may have to hand raise cubs if their mom is unable to raise them normally and these individuals tend to be much calmer around humans. That being said they are still wild animals and WILL kill you if you are not careful. Cheetahs are probably the only “big cat” that can be really tamed because when they are raised with dogs they basically act like they are just a very large weird dog. \n\nUltimately, interaction with cats or any other wild animal should be kept to a minimum. The whole point of zoos is to conserve wild animals usually by supporting captive breeding and eventual release. Interactions with humans can disrupt their normal behavior or cause undue stress on the animal.",
"Wild animals are aggressive when they are hungry or feel threatened, well-fed animals that know they are safe are less aggressive. They instinctively do not waste energy unless there is a compelling reason to do so.\n\nA particular wild animal cannot be domesticated, that takes generations. They can be *tamed*, where they learn to coexist with humans without harming them. Even so, they are still wild and can be dangerous, ask Siegfried and Roy about that."
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2ptu19 | how can instagram be worth 35,000,000,000 dollars? | I cannot comprehend how a company that is not making money and is so simple that it could be replicated in a week, can be valued that high? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ptu19/eli5_how_can_instagram_be_worth_35000000000/ | {
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"Current electronic services (in the social networking and communication realm) are valued at least in part by their user base (size and complexity). When people willingly post all the things they like the most, then the company allowing the space for posting keeps the information about that user. It is generally considered more valuable if you know specific characteristics about each user because you have a chance to sell advertising space to services and companies that are *without a doubt* going to be of interest to the user when they see them. This is considerably better than paying for a billboard on the side of the road. So this specific marketing is very valuable and I imagine they skyrocket the normal value of advertising to a premium level (because expensive means it's better, right?) and then multiply that by the size of their user base. Bam. $35B. \n\nIn my own opinion, however, it's not worth 1% of that. It's market idiocy and just another example of how marketing makes the product, not the product. See Beats by Dre as an example. Also, the value is considered in global market value, not just domestic markets. A lot of Global businessmen would like to buy a hugely popular *site* (or anything, really), if it will give them critical data on the habits of the American youth and an opportunity to push your partners' products and services to them."
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5zajsk | crude oil | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5zajsk/eli5crude_oil/ | {
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"To refine crude oil you pretty much have to distill it like a hard liquor. But since it comes out of the dirt it is usually somewhat dirty so they have machines that filter the sand and salt out first so it doesn't ruin the machines. The equipment is similar to what is used at a rum distillery expect that there are many types compounds that condense at different temperatures and are separated to be used for different purposes."
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1wn1j3 | why are modern day toys and electronics so flimsy compared to, say 15 years ago? | These days mobiles, earphones, televisions etc just seem so "flimsy". I suppose most people can relate to the old Nokia phones that were built like lightly armoured tanks. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1wn1j3/eli5_why_are_modern_day_toys_and_electronics_so/ | {
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"Consumers would rather pay less and buy devices more often. If there was more profit to be found by charging more and being durable, that's what you would see. \n\nThe obsolescence curve for many technologies is also getting faster, so manufacturers can more safely assume their product will have a shorter life anyway. ",
"1. To lower costs\n\n2. To make mass production easier"
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cc1fpv | why do 78% of americans live paycheque to paycheck? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cc1fpv/eli5_why_do_78_of_americans_live_paycheque_to/ | {
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"text": [
"Wages are low, prices are high, and any progress you make can be wiped out in a day by an accident or illness."
]
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1lga3l | why not vote for a third party if dem. and rep. are so similar? | It wouldn't change anything the first election, but if it catches on, the parties would see that and start doing something. How hard is it really to select a third ticket when voting? In my mind, it's mostly about sending a message, but I'm getting the impression people can't wait for results these days, so 8 years until you'd optimistically see a result...
-----
Edit: My question isn't about how the voting system works, but more about the psychology or culture (not sure which) that makes people stick to two parties **when they consider them equal** instead of voting for a third party. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1lga3l/why_not_vote_for_a_third_party_if_dem_and_rep_are/ | {
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"While you're waiting, you're also hurting the chances of the major party you disagree with least (because you could've voted for them instead). This is called the [spoiler effect](_URL_0_). That's one reason.",
"Because the vote is basically wasted. This is exactly why i think they should start implementing single transferrable vote as it has a chance to (albeit it slowly) let other parties grow their vote. ",
"This is a very good video explaining the problem of the political system in America in a simple way suitable for eli5. _URL_0_"
]
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73zxp1 | why does buying stuff (non-essential) make us happy? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/73zxp1/eli5_why_does_buying_stuff_nonessential_make_us/ | {
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"It depends on what kind of stuff you're buying, but essentially, it's because products are advertised as lifestyle components rather than things. E.G. You're not buying a Mercedes Benz, you're prestigious and the envy of others. You're not buying Prada sunglasses, you're chic and classy. You're not buying TOMS shoes, you're saving the world. \n\nOf course, this is a pretty empty, fleeting happiness. Partly because manufacturers need to keep selling stuff, and advertise how much better their latest and greatest products are (even if they are functionally the same as the old ones). But also because of ingrained human nature--if we were permanently happy from any one thing or things, we would have stagnated as a species.\n\nRelevant LifeHack--*If* you're going to spend money pursuing happiness, spend on experiences, not things: _URL_0_",
"I'd guess because we are hardwired to be hunter/gatherers and acquiring things triggers our mental reward system.",
"Because advertising works! I note that it doesn't make everyone happy.. it makes me quite sad to see people buying non-essential junk as I know it is hurting the planet. However other people seem to find meaning in owning \"stuff\"... they think that having whatever they \"want\" as opposed to need items only makes them more complete. They have been told that \"The American Dream\" is having everything you could ever want... and nobody was told that having junk is killing the planet. \n\nIt's gotten so bad that people find comfort in collecting things or hoarding them.. for some reason people find value in this.\n\nPeople have been told that if they see something they want it doesn't matter if they need it or not.. they \"deserve\" to have it.. so people are brainwashed into thinking that stuff = happiness.\n\nBasically people are told to buy junk to be happy because it means they have to work more so they can afford all the stuff.. more people working = more people paying taxes. A win for the government, a loss for the planet and a loss for common sense."
]
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2uu62d | why do we grieve? | Why do we feel grief, painful, agonising grief, over the death of someone? They're not in pain any more, or danger, nor will they ever be again. So why is it that it makes us feel so bad? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2uu62d/eli5why_do_we_grieve/ | {
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"Cognitive scientist and evolutionary biologist Steven Pinker wrote about this in his book How the Mind Works. He argues that evolutionarily that grief serves to make the death of our loved ones so painful that we will do anything to prevent it. This is important because our purpose from an evolutionary stand point is to assure that we pass our genes on to future generations. That includes keeping our progeny and our mates etc alive long enough to pass on our genes.\n\nEdit: Typo",
"I think it's twofold.\n\nOne, we grieve for ourselves. We felt respect or love or fondness or affection or some other emotion for the dead person, and we grieve that they will not be here *for us* any longer.\n\nTwo, people in general don't believe in an afterlife anymore. Death therefore means the end of a person. We grieve for their lost opportunities."
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2v6a2p | i hear that snipers have to take into account multiple factors, from wind speed to rotation of the earth. what exactly do snipers do to account for earth's rotation? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2v6a2p/eli5_i_hear_that_snipers_have_to_take_into/ | {
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"they simply must take into account the rotating reference frame (Coriolis effect) when firing their projectile and make the appropriate adjustment for that. This only happens at extremely long range in regards to rifle ballistics and is minimal but important when trying to be as accurate as possible. In the northern hemisphere one must aim to the left due to the rotation of the earth left and the opposite in the southern hemisphere. This effect is negligible at the equator but the farther north or south one goes the more of an effect on ballistics the rotation will have. \n\nThere are a set of calculations that can be done to find the exact necessary adjustment and military shooters are taught the long hand form of this but nowadays things like spotting scopes and handheld ballistics computers can manage the calculations automatically when the necessary variables are entered. If one knows their rifle well enough and shoots at various ranges it becomes second nature to make adjustments based on range for a variety of different factors, from bullet drop, windage, angle of firing and the Coriolis effect.\n\nI am by no means an expert in this but that is what I know about the ballistic effects based on my personal experience when firing rifles for long range in different conditions"
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4di848 | how do software-based translators (like google translate) work? as in, how do they "think" about the sentence and go about translating it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4di848/eli5_how_do_softwarebased_translators_like_google/ | {
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"There's an entire area of computer science dedicated to the R & D of this called Natural Language Processing. I don't know too much about it yet, but it's a field I'm interested in working in at some point in the future. What I can tell you (which, please, should be taken with a grain of salt) is that languages can be broken down into rules, and with these rules, a kind of 'sentence equation' can be formulated. When paired with, for instance, Google's massive database of common verbiage, natural-sounding translations are possible.\n\nMay not be a complete answer, but hopefully you learned something!\n\nWikipedia link on natural language processing: _URL_0_"
]
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4n7g33 | does cancer hurt? how do people typically know they have cancer, initially? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4n7g33/eli5_does_cancer_hurt_how_do_people_typically/ | {
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"Depends on the type of cancer, but yes, it *can* hurt and that *can* be the initial symptom that you'd notice.\n\nOther times it can just be a mole that's growing in what seems like an uncontrolled way, or a lump in your breast. This is why you have to pay attention to those things.\n\nOther times it can be as extreme as making parts of your brain function incorrectly. In these cases you might not notice until that happens...\n\nThe thing is, \"cancer\" isn't really one disease. It's an umbrella term for many, many different diseases that act in similar ways. So there's not a single answer for this. ",
"Having cancer can be painful and if left unchecked it will become painful. As cancer spreads, tumors grow in different parts of your body. These tumors can block passages in your body or press on nerves, both of which can be painful. Cancers can also break down or inflame tissues as they spread, which can also be painful.\n\nFortunately, modern medicine can detect cancerous tumors before they become painful. And the earlier you detect cancer, the better your chances of removing it. However, there are a lot of different types of cancer and they all act somewhat different, so that's whether pain would be the first thing you notice depends on the type. I also don't have numbers on how people found out they have cancer, so I can't say for sure, but I'm guessing most people in the developed world find out they have cancer from medical screenings or from detecting an unusual lump.",
"You know the joke that if you go to webMD to find out what your symptoms mean it will always tell you it's cancer? That's because the many different kinds of cancer can potentially cause *any* symptom.",
"My testicle kept getting larger very slowly until the point my entire abdomen hurt so bad I couldn't sleep for 3 days straight. I went to the ER and was diagnosed with testicular cancer that had spread to 2 lymph nodes in my abdomen. Then I had terrible back pain because the cancer was growing into my muscles and crushing them. Once I started chemo I don't have any pain at all anymore because testicle cancer is easily killed with chemotherapy. 6 months time I should be ok. \n\nLong story short the cancer itself doesn't actually hurt. It hurts when the cancer starts to apply pressure and crush other parts of your body ",
"I had abdomen pain where my gallbladder \"used\" to be. Went in for a routine checkup, turned out I have a rare form of cancer called bile duct cancer.\n\nSome people I have met have similar things. One person always fealty achy, as if their very bones hurt. By the time she had visited her Dr and went thru screenings, she had stage 3 bone cancer. Another person I met had frequent headaches that kept getting worse and no med would touch it. By the time his HMO had worked him thru the approval process to see the various Dr's, he had a cancerous brain tumor that was irritating the brains menege, causing the headaches.",
"ELI5: To break it down easily for you. Cancer is the abnormal growth of tissues/organs/systems in your body. The growth may not be painful, but when it presses up against another tissue/organ/system, that infringement may be painful/discomforting as a result. When you feel that internal pain, it is/will be like no other pain felt before, because its coming from the inside from an area that you may have never felt pain before. If you feel these pains, see a doctor as soon as possible. Perhaps its an errant pulled muscle. Perhaps its something else. Better to know than to be blind to a potentially fatal issue.\n\nHope this helps! Peace!",
"My partner first noticed an itchy mole and a diagnosis of melanoma was made from a biopsy of this mole. There was no pain for much of the time he had cancer but once it began spreading into his bone marrow, lungs and lymphatic system that was when the pain really began, 2 years after diagnosis. He suffered a rapid painful decline and died in January. At the end he was taking a combination of morphine and ketamine to try to control the pain. In melanoma it would seem that changes in the skin are the first sign and the pain arrives long after diagnosis. "
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5lmx2o | why was amputation so common during the civil war? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5lmx2o/eli5_why_was_amputation_so_common_during_the/ | {
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"Because medical technology was not advanced enough to repair shattered bones and shredded blood vessels. The most effective way to save the life was to remove the severely injured limb. ",
"This was before antibiotics and germ theory, so the only way to stop gangrene was to cut off the affected limb. A new type of bullet, the Minnie ball, also caused more grievous wound.",
"The biggest reason is that they were shooting ridiculously huge \"minie-ball\" ammunition that would absolutely destroy bone as it passed through the body. They had no way to repair this damage. On top of it, antiseptics and antibiotics were limited (at best) and the sheer volume of patients meant it was impossible to take the time necessary to meaningful surgery. \n\nYou can read more here: _URL_0_",
"Not just the civil war, but in the times previous to that -- when you have major damage to a limb, but medical technology hasn't progressed to the point where you can repair an artery, then you have to amputate the limb or else the person will bleed to death.",
"Two reasons , Black powder muskets and lack of sterilization or even the concept of it .\n\nBlack powder is a weak propellant so requires more powder to make the bullet go farther which in turn means a larger diameter bullet. These large bullets did horrendous damage to bones and blood vessels and medicine at the time had no way to repair it, so amputation was the answer. Even if the bullet did not strike a bone or large blood vessel it would leave a gaping wound which needed to be bandaged . Since they had no idea of sterilization they would reuse bandages after a light washing and put them on the next patient. This almost always infecting the wound and then arm or leg would have to be amputated later because of gangrene, and then re-use that bandage thus infecting the next man . "
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1dfgc5 | tontines. how do they work? how did people scam other people? what is the benefit? | I was watching an episode of Archer that talks about tontines. I googled it but I'm not sure I fully understand. I know there's a pot that the last living contributor inherits but then I read about annuities and corruption and such. It sounded simple but I'm actually lost. I'm thinking about writing it into a script. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1dfgc5/eli5_tontines_how_do_they_work_how_did_people/ | {
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"The episode did a good job of explaining what they are ^(DANGER ZONE!). A bunch of people pay money into a pool, the money is invested, and the last living member gets the entire amount.\n\nThe only scam I know of is that someone goes around and collects money for it and then just takes the money and skips town. It may take a while for the scam to be discovered since the money taker is supposedly investing the money and no payout will happen for a very long time.",
" > Burns: Then it's agreed. Of course, we can't sell the paintings now, we'd be caught. How many of you are familiar with the concept of a \"tontine\"? \n\n > > [all stare at him, until Ox raises his hand]\n\n > Burns: All right, Ox. Why don't you take us through it?\n \n > Ox: Duh, essentially, we all enter into a contract whereby the last surviving participant becomes the sole possessor of all them purty pictures.\n\n > Burns: Well put, Oxford."
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2ui4xt | why does chinese still use a pictorial writing system rather than moving towards a phonetic system like most languages use? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ui4xt/eli5_why_does_chinese_still_use_a_pictorial/ | {
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"I speak, read and write Chinese (simplified/mandarin) . These are just my thoughts. (don't quote me on this) \n\n \nFirstly it is not easy to implement a phonetic system. It involves lots of changes to education and society which costs money and will take maybe a decade to transform. It's probably easier to change all the imperial system in US to metric. \n\nSecondly, the Chinese traditional culture involves calligraphy which can be lost if a phonetic system is implemented. From my \"history lesson\" in China (sorry for not listening in class) I remember Chinese characters are developed from \"drawings\" to make them look like the object, 人 which means human looks like a man with two legs (and torso only, you get what I mean) \n\nLastly, a lot of Chinese characters sound the same but have totally different meanings. Sometimes the same character can have different pronunciation which gives different meanings. For example 长 when pronounced Chang2 can mean \"long\" but when pronounced zhang3 can mean grow. \n\nEdit: although Cantonese (experience from my trip to Hong Kong) and mandarin does not use exactly the same system but it is really close and anyone with a little bit of learning (mainly the slang? I'm not sure what the English word to use for this) can read both easily. "
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7ppt8o | why are cartridge based video game systems inferior to disk based ones? also, why did cartridge based system not have load times? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7ppt8o/eli5_why_are_cartridge_based_video_game_systems/ | {
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"They are larger and hold less data. They are also significantly more expensive to produce.\n\nThey don't have load times because there's no moving parts. It's solid state memory. No laser needing to read a disk.",
"Cartidges required a small printed circuit board for each unit they sold. The advantage it there was a direct electrical contact which enabled the data to be read much more quickly. The disadvantage is the cost to produce each cartridge. Optical media is far cheaper to produce, but the disadvantage is the read speed of your optical drive. ",
"The time cartridges were popular, solid state memory was very expensive, as well as cartridges taking a lot more manufacturing and parts to construct. So when CDs came in, they were cheaper to mass manufacture, and stored a heck of a lot more data, so the fact that you had loading times most people considered a worthwhile sacrifice. ",
"cartridge based is not necessarily inferior in fact it's actually far superior to optical media. The data reading speeds that you can get from solid state memory is far faster than any optical drive could hope to achieve and you can even add on board memory storage for things like game saves. There are still load times just in the past (and still today in some cases for the switch) the data speeds have been so fast and the games used to require so little data that it seemed like there was no loading time. \n\nIt's all about how fast the system can move data from storage into it's memory and if it can do that super fast it may seem like there's no load times. Also no moving parts basically eliminates the chance of something breaking outside of user error.\n\n The downside though is it's many times more expensive than the cost of a disc and getting the same amount of storage that say a dual layer blu ray gets(ps4 / xbox) is insanely expensive. So discs are cheap and can store large amounts of data these days and modern PC's and consoles have plenty of storage these days so it's easier just to use the cheaper medium and require the installation games these days. This saves the manufacturers money but it also helps to keep games cheaper for the consumer as well. It also means means developers don't have to try and gimp their games to make them fit on a smaller size cartridge in order to save money something that is already becoming an issue on the switch.",
"Former game developer here,\n\nCartridge games are absolutely not inferior at all. It all depends on what you need. Cartridges are still used by Nintendo for their hand-held and mobile gaming platforms because they're not fucking morons like Sony and their total flop that was the PSP. Cartridges don't scratch, they don't rely on moving parts, or lasers, and are immune to vibration. They also take a lot less energy to operate, important for battery life.\n\nThey don't have a load time because they're effectively an extension of the rest of the circuitry. You don't have to spin up the disk, move the laser into position, find the beginning of the first track, decode the partition headers, then seek to the right position of whatever track to start reading data. And any bump, you have to re-seek. Flash memory has physical address lines right to the NAND gates.\n\nIf your only criteria were data density, then optical drives might be higher than flash cards. Where they do win is cost. An optical disk costs something like $0.0017 each or something, based on the last time I tried to calculate it.",
"I think this is mostly answered already (discs are stupidly cheap, basically).\n\nThere's some interesting stories from the super nintendo days in this general area. I believe the snes was originally intended to have an ram expansion but nintendo took too long so some game devs started to get creative and started putting extra capabilites onto the cartridge itself (ever notice that some carts were significantly heavier than others?). This later lead to a lot more difficulty when creating emulators for the systems, because all this extra hardware needs to be handled by the emulator, but it only exists on some carts. \n\nAnother fun side story is the planned disc drive expansion from a partnership with sony, which was to compete with the sega saturn. When the saturn tanked, nintendo backed out and sony turned the project into the playstation. "
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6t15rm | what do programs like handbrake do to compress videos? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6t15rm/eli5_what_do_programs_like_handbrake_do_to/ | {
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"Yer not alone in askin', and kind strangers have explained:\n\n1. [ELI5: What does compression do to a video file, besides reduce file size? What are the cons of watching a \"compressed\" copy of a movie? ](_URL_1_)\n1. [ELI5: How video/image compression works ](_URL_4_)\n1. [ELI5 how does file compression work? As in .zip, .rar, etc. ](_URL_3_)\n1. [ELI5: How does file compression work? Where does the data go? ](_URL_2_)\n1. [ELI5 why does compressing video or audio sacrifice quality? ](_URL_0_)\n"
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3fqx9r | why do we use tires full of air instead of solid rubber tires or another type of tire? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3fqx9r/eli5why_do_we_use_tires_full_of_air_instead_of/ | {
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"If it was made of solid rubber we would feel every rock and divit, the air helps with shock.",
"Have you ever rode an old bicycle with solid rubber tires? Say goodbye to your butt.",
"Your lumbar vertebrae would not be amused by that.\n\nEver rode in a car with wooden wheels, or a horse carriage? Those don't go more than a few MPH under normal circumstances, and aren't exactly a Benz. ",
"Plus, the added weight would VASTLY decrease your fuel mileage, as well as add strain on your transmission and engine, causing you to need more frequent maintenance. You also have balancing of the tire to consider. What happens when You flat spot that bad boy? Shave the whole thing, changes the tire size and damages your bearings. \n\nBad idea overall.",
"A lot of research has been done on [airless tires](_URL_0_), which are neither solid nor pneumatic. So you may ride on these someday.",
"Actually the first tires were solid rubber and they are still used in some applications (skid loaders like Bobcats commonly have solid rubber tires). While they are stronger and do not flat, solid rubber tires are uncomfortable, use more rubber material, are heavier and are less fuel efficient. Riding on air filled tires gives a more cushioned ride, uses less rubber, are much lighter and thus deliver higher MPG.",
"Full rubber would be more expensive, heavier, acceleration would suffer, and gas mileage would suffer.",
"There's several advantages of a rubber tire filled with air: they are lighter (less energy to move them / better mileage, and much easier to handle them when changing a tire), they flatten out when touching the road to get better grip, they absorb some of the bumpiness of the road for a smoother ride, and there's considerably less material used than would be for a solid tire.\n\nI suspect that in the future, we may well use tires filled with a super-lightweight spongy material that will eliminate (or lessen the impact of) flat tires.",
"Funnily enough the first fires were solid. That's why you see those old photos of Ford flat beds stacked twice as tall as the truck, they stacked on cargo to weight limit of the rims/axels, not the tires. \n\nAir tires act as shock absorbers which improve ride quality and decrease wear on the suspension\n\nCurrently mobile, but there's lot of\n info on that if you Google history of American trucking. The history channel did a show over it.",
"Since this is EIL5: Try riding a skateboard down a gravel road. The wheels would be too hard to roll over anything without making everything much less stable.\n",
"Or what about how newer cars have the option to fill the tires with Nitrogen instead of air, what does that do for them?",
"- Shock absorption properties: \"hollow\" tires that can flex allow the dissapation of force as the tire rolls over non smooth terrain.\n- Cost: Rubber is a fairly expensive material compaired to air. Since a stable, resiliant tire can be made with a hollow inside, it can be made cheaper.\n- Weight: Cutting down the weight of a vehicle lowers the fuel use over the same amount of distance. ",
"A lot of people are saying that it is for shock absorption, but that is only a minor part of it. The real reason is heart dispersal - solid rubber tires would have a lot of material being flexed almost constantly and would generate a ton of heat and have nowhere to go with it, so they would shred very quickly at any decent speed.\n\nEdit: auto correct",
"1). Air helps absorb shock\n\n2). Air helps the tire deform better for less-than-favorable conditions. (For instance, the IDF found that deflating HMMV tires improves their performance on sand).\n\n3). Air massively reduces the material cost/weight.\n\n4). Air is available everywhere except the ocean and space.",
"All rubber has the potential to take a \"set\"- when left compressed in one place for a long period of time, they develop a lump. The compressed side does not spring back out 100%, not right away. It may come out after a few minutes of driving, but it's a mighty rough ride until then. Set happens quicker at higher temps, but remedies itself faster at high temps. Sometimes part of the set is essentially permanent, though.\n\nIn pneumatic tires, the support doesn't come from the rubber. The rubber is flexible and conforms to the road and can't take a significant set. The air pressure, obviously, cannot take a set either.",
"A solid rubber tire would be quite heavy. All that unsprung mass on the wheels would cause the car to handle horribly and the steering would feel extremely heavy. This is why high performance cars usually swap out steel wheels with lightweight aluminum and low profile tires. With that being said tire manufacturers are working on airless tires that resemble bike wheels with spokes of flexible material.\n\n_URL_0_ ",
"Part of the reason is a solid piece of rubber would weigh significantly more than a tire filled with air. More weight means more fuel, more energy to slow down, more stress on supporting parts, etc. There's no reason for a tire to be solid rubber.",
"If you reinforce the thin rubber walls with steel rebar wires, it's much stronger than solid rubber tires in terms of durable and wear/tear.\n\nIt's also much cheaper since you use less rubber in production of the tire. \n\nAlso, solid rubber tires are super-heavy, so that consumes a lot of energy (ie. gas) to turn four - heavy wheels compared to lighter wheels.\n\n",
"We used to, but the tires were more expensive, and they didn't absorb shock nearly as well."
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bwonff | what do you mean by economies scale? | I've read that term mainly while doing cost estimation for wind/soar projects. Confused what does that exactly mean. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bwonff/eli5_what_do_you_mean_by_economies_scale/ | {
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"Economies of scale means the more you buy the cheaper each unit becomes. One unit may cost one dollar, but five units may be only cost four dollars",
"I believe it refers to how businesses spend less money on their production because they get bigger. so as the business grows, their average costs go down because of things such as bulk buying, specialization, marketing economies etc.",
"The other answers have it right, but aren’t giving very concrete examples.\n\n\nThe more you are going to use something, the more you can spend on it without changing the cost per use.\n\nIf I want to make a LEGO, I can use my 3D printer and get a pretty good LEGO piece. It will take about 3 hours, and then when it gets done I need to treat the piece to remove the weakness of being built with stacked layers of plastic, or it will shred apart when I try to get it unstuck from whatever I build. Plus to get it to fit as well as a normal LEGO, I would need my printer to be VERY well configured. This can easily take a few days of work on older printers.\n\nTo make a LEGO without a 3D printer would likely take even longer, and be far harder to get the precision I need with hand tools.\n\n\n\nSo, how are LEGO pieces made?\n\nThe company builds metal molds to inject plastic into. Then the pieces are measured to ensure they are EXACTLY the right size in every location along the part. If they are not perfect, the metal mold needs replaced/repaired. These molds cost many thousands of dollars (my memory wants to say a few million, but I find that hard to believe).\n\nLet us claim the mold costs $20,000 and the machine to use the mold costs $150,000. The mold can make about 20 million parts before it has to be replaced, and the machine can last as long as 1,000 molds. The plastic used for one piece costs 0.3 cents\n\nIf I want to make one piece, using professional gear, it will cost me $170,000.003 per piece. I definitely want to hire a company to do this for me on their equipment, meaning I only spend on the mold, getting the part for $20,000.003. Again, makes a clear easy choice to hire someone to do it by hand, paying them for at most 3 days of work, so maybe $1,500 there.\n\nIf I make as many pieces as the life of the machine, it will cost me 0.0040075 dollars per piece.\n\n\nSo... one off the major cost is production technique. But at scale, the major cost is plastic. The equipment I use to make the parts quickly, accurately, and easily are nearly ignored at scale.",
"\nIf you buy 100 solar panels, it's usually cheaper (per panel) than buying one panel.\n\nIf you build a factory that can make 10,000,000 solar panels a year, it's usually cheaper (per panel) than building a factory that can make 100,000 solar panels a year."
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dsin0g | how do specialists know if a very old skull was cracked before or after death? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dsin0g/eli5_how_do_specialists_know_if_a_very_old_skull/ | {
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"Bones do heal, so if there is any sign of healing or regrowth it pretty definitively happened prior to death. Color of the break on the bones can also be an indication. (edit to add that I didn't put any detail as to why color matters, but some very helpful other posters went into more detail below. Whether or not blood is still flowing at the time of injury and outside contaminants such as dirt will impact bone coloring) \n\nBones after death are also drier and more brittle and as a result tend to shatter, so the fracture will look different.\n\nEach of these things can arise from other scenarios or can be unclear, but multiple signs all pointing to the same conclusion are usually a good indication if it is a ante-mortem or post-mortem injury.",
"Even bone will heal. And when bone heal it will round off any sharp edges. By looking at how sharp the edges of the broken bone is you can determine how long someone lived with the broken bone. So a cracked skull will look different if it was cracked a few weeks before death then if it was cracked around the time of death. In addition when the body is rotting it changes the bone which makes it break differently then if it was in a live body. So if someone died and were burred then later on got uncovered and their skull got cracked it is possible to see how that break is different from how the break would have been if it was around the time of death. Using these techniques it is possible to piece together a rough timeline of the wounds on a skeleton. Of course it is not precise enough to determine the exact cause of death but it can tell if a wound was sustained around the time of death.",
"Like other said bones will heal if they were broken before the death. In addition, when you die your blood doesn't flow anymore and the blood stain on the bones will be different.",
"The answers you have so far are pretty incomplete, so I'll try to explain in in an ELI15 way. This is a field involving trauma analysis in forensic archaeology/anthropology or palepathology. I'm assuming you are asking how we tell the difference between antemortem (before death), perimortem (at the time of death) and postmortem (after death) injuries. \n\nOn a basic level, what some other people were saying is correct. Bone is a living tissue and will show signs of bone repair in the skull. Fracture edges will appear rounded and smooths, and broken pieces may be rejoined in antemortem fractures. There may be a large depressed area of bone and fracture line near the impact site.\n\nPerimortem injuries can have similar bone breakage patterns to antemortem trauma, but show no signs of healing. Since the bone is green/fresh/wet bone when the trauma occurs, the fracture edges are shapr and clean - not jagged or torn like dry (postmortem) bone breaks. Blunt force trauma can leave indents of the of the weapon used to inflict the mark. This is especially true, since surrounding tissue and the brain can prevent the skull from shattering.\n\nPostmortem trauma is typically caused by the environment, like damage from carnivores or rodents, or being compressed by soil. Bone can also become damaged from decay, sun, heat, moisture, etc. No healing is evident, and the bone is dry and more brittle. As a result, dry bone fractures are typically more jagged or torn, with random breakage patterns. More like you would see in a ceramic pot or something. The fracture edges are also typically lighter in color, since they have been exposed to the elements for a shorter period of time than the surrounding skull (think when you move a piece of furniture and the carpet underneath looks cleaner). There are some other ways, but that's a basic overview. \n\nSource: have a M.S. in forensic science. Am forensic scientist.",
"Trying to fool the coroner, are we?"
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1rnn46 | is it better (for the battery and for the next charge) to use all of the power in rechargeable batteries before recharging them? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1rnn46/eli5_is_it_better_for_the_battery_and_for_the/ | {
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"Only for old, NiCd batteries, otherwise they can develop the \"memory effect\" and wind up with less capacity.\n\nFor anything newer you do not want to fully discharge the battery as it can damage the cell. For new Li-Ion batteries you ideally want to keep it at around 80% charge as much as possible.",
"It depends on the type of battery. Modern lithium batteries don't have [memory effect](_URL_0_), and it's actually healthier to avoid a full charge/discharge cycle - instead, keep it partially charged.\n\nThe memory effect only affects older nickel-based batteries."
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75ep1i | how did the human race start? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/75ep1i/eli5_how_did_the_human_race_start/ | {
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"Humans evolved from other primate species that were similar to humans. It happened in many tiny steps, not suddenly.",
"You really can't pinpoint any time when a species starts. \nEvolution happens to populations, not individuals. There's an unbroken, gradual change from one species to the next, or one species branching into multiples. \n\nHumans and early human ancestors were omnivores that lived in groups, originating in Africa. There used to be many human species or subspecies (depends who you ask) alive at once, who interbred. But for an unknown reason, only *Homo sapiens* survived to the modern day. "
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2yqyg9 | what makes a consumer good higher quality when 'made in mexico' versus 'made in china'? | I've been windows-shopping at guitars and it seems like the 'low-quality' ones are made in China, where as the 'mid-quality' guitars are produced in Mexico. Obviously, Chinese workers can be paid less, but why not pay them more and use efficency wages to encourage better quality control? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2yqyg9/eli5what_makes_a_consumer_good_higher_quality/ | {
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"You can have very high quality stuff made in China, if the company you're buying from is willing to spend enough money to have high-quality stuff manufactured.\nIt's just that China has mostly specialized in making *cheap* products rather than *high quality* products. Cheapness has to come from something... while the wages (and thus, skills of the workers : low-wages attract unskilled workers) are a factor, there's also the quality of the material your stuff is made of, the amount of quality-control, the pace at which it's manufactured (the more time per manufactured unit, the more it can be tinkered/meticulously made, but then you can't make as many per units so it costs more), etc.\nChina has really been an expert at making cheap stuff (which came with a tradeoff regarding quality). But nowadays they are very well able to manufacture high quality products... but then it starts to cost almost as much as manufacturing it in any other country so why bother?\n\nIn other-words : China doesn't manufacture \"low quality products\", it manufactures \"cheap products\". Your mid-quality guitars from Mexico are more expensive and not everyone can afford them. There's a (huge) market for cheap products that everyone can afford. China is a leader in that market and has no reason to stop supplying a market that generates tons of profits."
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4n0va6 | if the presidential primaries award proportional delegates, why is the general election winner-take-all? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4n0va6/eli5_if_the_presidential_primaries_award/ | {
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"Primary rules are up to the parties themselves as independent groups deciding how they want to get stuff done. They are not all proportional, for instance, they can vary by party, and by state. Many(most?) of the republican contests, for instance, are winner take all contests.\n\nElectors are also not necessarily winner-take-all in the general election. Their awarding is decided through state law and/or party agreements. Nebraska and Maine, for instance, both award their electors proportionally. \n\n > Seems needless and confusing\n\nWell, the more confusing you make it, the easier it is to game. At least, that's my cynical opinion.",
"Technically, the general election isn't *necessarily* winner take all. It's up to the states to decide how their votes are apportioned. 48 states use winner-take-all, but Maine and Nebraska both give two votes to the statewide winner and then one vote for the winner of each congressional district (two in Maine and three in Nebraska). As it happens, both states usually end up awarding all of their votes to one candidate.\n\nAs for the discrepancy between the primaries and general election, they're entirely different beasts. The general election is run by the government and the rules are defined by law, but the parties can decide who they nominate however they want. It wouldn't even have to be an election; they could decide by a game of hopscotch if they wanted to."
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1wbhau | when i download a 2gb file on my computer, does that use up 2gb of my wifi data? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1wbhau/eli5_when_i_download_a_2gb_file_on_my_computer/ | {
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"Yes. Probably more, as at the protocol layer you are sending traffic and from the server.\n",
"In the context of a data plan, data is defined as any activity on your WiFi. That means downloading **and** uploading. So yes, you will use **at least** 2GB of data.",
"Yes, can be anything from 10-33% (on average) overhead because of encryption and packet loss.\n\nSo your 2GB file will probably use between 2.2 and 2.65 GB of data."
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7e4op2 | being in shock/adrenaline | Anytime I hear stories about a person getting into an accident, sometimes where limbs come off, and they act normal, like they will walk towards their car, sit down and chill, or call ambulance, or whatever. Someone in the comments will always ask why, and someone will reply saying because they are in shock. What is shock really? I feel like if my arm just came off, there's nothing I can do about other than chill out and call emergency, would this be considered "shock." Obviously, the adrenaline would mask most of the pain but screaming in agony or just looking at the wound won't help so whenever I see a person in "shock" I don't really think they are out of it, I think they are composed and accepted what just happened. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7e4op2/eli5_being_in_shockadrenaline/ | {
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"Shock is when your blood pressure is substantially lowered caused by (mainly) physical trauma. Poor blood pressure = cell damage, disoriented, confused. altered consciousness basically a lot of stuff happens to our brain when our blood pressure is lowered drastically. In instances where people are in an accident and have undergone an injury to which an unaffected person at the time would be freaking out about if observed, but the affected person remains calm but sort of \"out of it\" - this would be adrenaline. Adrenaline would kick in before shock because its our defense mechanism known as fight or flight. Your brain basically directs all its attention to keeping your body alive. Therefor there is basically no concentration being used towards pain or shocking visuals - just solely on figuring out what you need to do to get out of the situation. Adrenaline is something that we can't physically control like holding our breath, it happens regardless. So people with a limb missing from an accident are having a huge adrenaline surge and remain calm because the part of the brain that is response for pain shuts down to keep the person concentrated and alert for danger.\n\nThis is why when people that do excessive amounts of amphetamines feel almost no pain or at least don't react to it. This is because amphetamines are a stimulant that release a crap load of mainly dopamine but also Adrenaline. Basically you're putting your body into fight or flight for no reason.\n\nHope this helps. "
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4aossc | why are buildings evacuated when given a bomb threat? surely if someone wanted to go through with a bomb threat they wouldn't warn beforehand, so as to get as many casualties as possible? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4aossc/eli5_why_are_buildings_evacuated_when_given_a/ | {
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"If your threatening them with a bomb you want something from them. If you just wanted to kill people then yes you shouldn't call ahead, but sense they are they want something out of it. ",
" > Surely if someone wanted to go through with a bomb threat they wouldn't warn beforehand, so as to get as many casualties as possible? \n\nYou're making an assumption that the bomber is only interested in casualties. \nBack during \"The Troubles\" the IRA would issue bomb threats, and then often have secondary explosives set up to try and kill the people dealing with the first bomb. This is because their target wasn't civilians, it was the structures that supported British power in Northern Ireland, which generally means soldiers and police. So by issuing the warning they were able to get civilians removed, and target brought in. \nOther examples of why you might issue warnings include blackmail (e.g. the Harvey's Resort Hotel bombing) or optics (e.g. give time for the media/spectators to arrive before you set the bomb off so more people see it). ",
"Sometime the primary goal is destruction of the building or area, rather than the people. By calling in the threat the building is evacuated and the bomb can be detonated without unnecessary loss of life of injury.\n\nAlso, not all bomb makers are the ones who place it, and not all people who place bombs are the ones who detonate it. Sometimes a person may be told the bomb was going to be used for one purpose, such as blowing up a bridge, but instead it is put in a crowded mall or hotel. Sometimes someone may be told to deliver a package somewhere and only finds out it was a bomb later. Sometimes people who work together don't like eachother, and the police are an excellent way to get rid of someone you don't want in your organization, without having to directly kick them out, especially if you don't want others to know it was you behind it.\n\nThere are many possible reasons that a bomb threat could be called in."
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6mv3rv | why don't we introduce sterile male ticks into the wild to eradicate them as has been done with mosquitos? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6mv3rv/eli5_why_dont_we_introduce_sterile_male_ticks/ | {
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"We did not introduce a sterile male mosquito. We introduced a genetically modified male that produced offspring that is sterile/does not get to maturity. We have not discovered a similar modification for ticks. ",
"If you release a bunch of sterile male ticks, they won't reproduce, and the not-sterile male ticks will. This doesn't really help, unless you reduce so many that you overwhelm the entire tick population with sterile ticks (which would be hard to produce) or you can produce ticks that *do* reproduce, but produce sterile offspring, so as to naturally overwhelm the population. ",
"I'm thinking the biggest reason is public acceptance. Male mosquitoes don't bite so releasing millions can only help and not hurt anyone.\n\nMale ticks do bite (however, they don't transmit lyme disease). People would be much less likely to agree to releasing millions of biting ticks.\n\nAlso, it requires millions to be released at once to overwhelm the numbers of wild males. We are exceedingly good at breeding mosquitoes in captivity. Not sure how good we are at breeding ticks in massive numbers.\n\nedit: added \"lyme\" thanks to /u/ihateuandurface",
"We really need to study the environmental impact of such a move, before making it. Something could be upset elsewhere if we purposely make a certain species extinct.\n\nWe've studied the impact of eliminating the mosquito, and our best guess is there are only positive benefits everywhere up and down the food chain. That it's safe to remove. But we can't haphazardly do the same with other species... ticks, rats, wolves, tigers... may all be dangerous to human populations but that doesn't justify forcing their extinction.",
"Do ticks even have any positive environmental traits?! Or are they expendable like mosquitos even though mosquitos are probably good for bat food and maybe some birds or something but not necessarily required.",
"The mosquitoes that were released weren't themselves sterile, but engineered so their offspring would be. The only mosquitoes that bite humans are pregnant females. So releasing males doesn't increase the likelihood of humans being bitten. Both sexes of ticks can bite and transmit disease so releasing any sex of tick would just increase contact. ",
"I remember reading somewhere that reducing or eliminating the mosquito population does not affect the food chain as they are not a direct and only food source to many of its predators . This does not have as much ethical implication when eradicating the mosquito population. Would this be the case as well with ticks?",
"All of the inaccuracies in the answers on this page makes this feel more like r/explainlikeyourefive",
"When did we eradicate mosquitoes? ",
"If I ever found a leprechaun or a genie my first wish would be to kill all the mosquitoes in the universe. ",
"Even doing it with mosquitoes is a huge debate and many still believe it's a pretty bad idea and that it will never come to pass on a global scale (it's been done on a pretty small scale so far). \n \nIt's somewhat justifiable with mosquitoes as malaria they carry kills many, but doing it to every species that are a mild inconvenience to us is a terrible idea. Morality aside (it is extremely immoral/unethical, though), we can't just destabilize ecosystems willy nilly and expect nothing bad to happen.",
"Where do you live where mosquitos have been eradicated? Not sure about elsewhere, but in Florida we have elected officials that do nothing but mosquito control (mosquito control board) - we have trucks driving around all the time at night spreading repellant or pesticide (honestly not sure which) and they're still everywhere.",
"NPR just did a thing about this on how to start by introducing mice that are immune to Lyme disease, to Nantucket.\n\nAssuming you are more concerned with the disease than the males' existence...\n\nFound it, here it is:\n\n_URL_0_\n\n\n",
"I understand mosquitos still fill a niche that is needed somewhat for predators like bats and birds to eat them, but why in the world can't we eradicate ticks? I mean of all the species humans have brought to extinction, can we really not just get rid of one pest, the tick, which are nothing but disease spreading nuisances? I mean all the predators of ticks are actually just generalists so they don't rely on tick populations to stay fed, they just occasionally munch on one for a snack.",
"Dumb follow-up question, but wouldn't eradicating mosquitoes and ticks harm the ecosystem?",
"First they came for the mosquitos, and i did not speak out - because i was not a mosquito.. \nThen they came for the ticks, and i did not speak out - because i was not a tick... \n \nWhere does it stop ? When everything annoying have been eradicated ?",
"Not to post speculation, but if I recall correctly the eradication of mosquitos has no negative effect on environment; it doesn't affect the food chain etc. ",
"There was a recent episode of Undiscovered that proposed a similar solution: introduce resistance to Lyme's into the local mouse population to prevent the spread. They went into the political challenges of implementing this kind of bio-engineering effort.\n\nWriteup and podcast: _URL_0_",
"Explains why I've seen tiger african mosquitoes in the last 2 years, that leave much worse inflamations after they bite. As opposed to local european ones that were relatively ok to deal with. \n\nThanks humanity, fuck you. ",
"We could just vaccinate against Lyme. Its not a big enough problem is the reason why neither of these things has happened yet. (Malaria is kind of a big deal)",
"I think there are a lot of things that eat ticks, mostly birds is my guess. I know chickens eat the little bastards. So maybe it just isn't a good idea to kill them off. Chiggers however, kill em all. They are like ticks but are so small you can't see them until it's too late and the bites itch more for much longer. [Wiki](_URL_0_)",
"How effective has the mosquito tactic actually been? As someone points out jokingly below, mosquitoes still exist obviously. I know the tactic has only been used in certain areas but how much has it really succeeded? ",
"Mosquitoes have been eradicated? My arms and legs beg to differ after camping last week.",
"I'm not sure where you got the idea that they use this method for mosquitoes. There has yet to be a large-scale sterile release program for mosquitoes. This method has been used for screw worm flies with great success but there are some hurdles to overcome before it is a viable method for controlling mosquitoes. One problem that still needs to be overcome is the sexing of mosquitoes, right now there is no good way of separating males from females at large enough numbers. Another problem is delivery. Mosquitoes are too fragile and tend to clump together when anesthetized, so releasing them from planes the way they do with flies isn't an option. For ticks I would think you'd have the same problem, separating males from females and how to deliver them, although I'm sure a tick would survive a fall from a plane just fine.",
"Side question: With mosquitos and ticks gone, wouldn't the flea population exploded to no competition of food? Would there be a massive vacuum pressure on natural selection for some species to fill that role? ",
"Because you usually have to be in a ticks environment for one to bite you. They don't just fly into your house.",
"Opossums would be ideal actually. Each one eats roughly 20,000 ticks / season.\n\nPlus there highly resistent to things like rabies, lyme, etc. They're awesome! Albeit a bit ugly",
"besides all the other points made it should be noted that we have absolutely no idea what the long term implications of this are. we should probably refrain from releasing designer parasites into the wild unitl we have long term (30-60 yrs) studies on the effect and potential for mutation... it should be noted also that about 1% of the \"sterile\" male misquotes were not in fact sterile, which equates to about 5-6 million mosquitoes that were genetically modified that can still breed, and we have no idea what the results of that will be... the last time we did something this (albeit unintentional release) we got killer bees out of the deal. i for one would like to avoid \"africanized mosquitoes and/or ticks\" thank you very much",
"Since when are mosquitos eradicated? What amazing fantasy world is this and how do I get there?!"
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1oo023 | how does a charge-coupled device (ccd) imaging system work? | I don't really understand what happens to create the image. Can anyone help me out?! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1oo023/eli5_how_does_a_chargecoupled_device_ccd_imaging/ | {
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"A Charge Coupled Device image sensor is like other image sensors in that it is made of a rectangular shaped array of very small elements that are sensitive to being hit by light. Each array pixel is like a tiny capacitor...the more light that hits it, the more electrical charge it collects. \n \nA lens system is used to focus the light onto the surface of the sensor, perhaps first after going through color filters. (Without color filters, the image captured would be just greyscale. With color filters, a sensor can collect separate images in Red/Green/Blue which can later be recombined for display.) \n \nAfter a brief exposure time, the different sensor pixels will have charged up to various amounts. In order to get the information off the array, it is typical that the charges are moved off in a \"bucket brigade\" fashion...each pixel's charge is moved to the one next to it, until all of them have been moved off the sensor array to circuitry at the edge that reads each of their values in turn. As a pixel is moved off and measured, that value is stored temporarily in a memory, either on the sensor chip or in a different chip. Then the next pixel in the row is moved off and measured, until the whole array is empty. \n \nOnce the whole set of image data has been read off and is in memory, a processor can do various things to it...compress it, format it as different image types, etc. Then it can be moved to a different memory storage location or to a host computer. "
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17ualm | apr | What is this and what is a good APR for a credit card? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/17ualm/eli5_apr/ | {
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"Annual Percentage Rate (APR) is the rate at which the credit card company charges you interest on your balance. The amount is compounded monthly. So, let's say your APR was 12% and you started with a balance of $1,000. The first month they are going to charge you 1% interest (12%/12 months) which works out to $10. Then, assuming you didn't pay off any of the debt, next month they're going to charge you another 1% but this time your balance is $1,010 so the new interest charges are $10.10.\n\nA good APR would be something below 10%."
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36f6ix | how do they "cut off" people's hands in movies? | I was watching Mad Max: Fury Road and I saw that Charlize Theron was "amputated" to the elbow. I know that she didn't actually cut off her hand, and that it's not CGI. How do they do this? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/36f6ix/eli5_how_do_they_cut_off_peoples_hands_in_movies/ | {
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"Just like when filmmakers shoot in front of green screens to create amazing landscapes, they put a green screen sleeve over the body part that is \"missing\" and superimpose the landscape over it"
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eudfvv | . i keep hearing about bernie’s healthcare for all. as a high schooler, i have no idea how healthcare works and have a hard time understanding articles because i don’t know what premiums, copays, etc. are. what is our current healthcare system, and what is healthcare for all? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/eudfvv/eli5_i_keep_hearing_about_bernies_healthcare_for/ | {
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"I live in the US, I pay an insurance premium of $213 every two weeks for my wife and I to have health insurance. When I go to a doctor's office I only have to pay a copay of $10 to see my provider, which would be over $200 without insurance. Prescription drugs have variable costs between $0 and $25 a month, with insurance I would be paying over $200 a month for medication. If I have to go to the hospital, I am responsible for the first $5,000 and 20% of the bill. Its complicated. This is what Americans call insurance. It can be incredibly stressful. \n\nRight now, I am in Northern Ireland, caring for my very I'll mother. This country has socialized medicine and in general she pays nothing, as she is retired. However, if she were working she would pay an insurance premium but from what I seen she pays nothing else. Her care has been very good and I am impressed with how little stress she experiences as she has not had a single bill that I have seen. \n\nThere are issues with both insurance models, but the latter seems much less costly and easier. \n\nHope I answered your question.",
"Our current healthcare system is maintained with health insurance companies. You pay them a premium for coverage, which reduces what you have to pay the doctor (your copay). There is currently a lot of debate regarding the future of the healthcare industry, because the current system doesn’t help everyone. There are government programs like Medicaid for low income families, but there are also a lot of people, like myself, who make too much for assistance but not enough to afford health insurance even through the plans offered by employers. \n\nThe Medicare for all plans would change our current for-profit system to one that is similar to some other countries. You would pay more in taxes, but you’d have guaranteed healthcare. \n\nThe debates surrounding the idea address several factors, like the increase in taxes paid and the concern with removing the current free market system. Both ideas have flaws, and there’s no way to keep everyone happy. \n\nIn my personal opinion, I like the idea of guaranteed healthcare. Too many people have had to go bankrupt or start go fund me campaigns to afford necessary care for things like cancer treatment. Fortunately, my teenager qualifies for the Children’s Health Insurance Program (CHIP) so he’s covered, but I’m not. What it means for us is that his doctor appointments cost us $20 out of pocket. For me, I went to the hospital a few months ago when I thought I broke my ankle. A few weeks later, I received a bill for $4500, which I have no idea how I’m going to pay. If I had insurance, my cost would have been $50 and insurance would have covered the rest.",
"The United States healthcare policy is, it's up to the individual to figure out how to pay the health care expenses. In other words United States leaves healthcare to the free market or our economy. Whereas in Canada, the health care falls under the responsibility of the government.\n\nSo in America as of today, if you we're having a baby you can pay anywhere upwards of $35,000. Now you can pay that in four ways actual;\n\n cash out of your pocket, insurance, a mixture of the two, or if you have little to no money, the government will pay for you anyway.\n\nThe problem is due to corporate greed healthcare cost have skyrocketed while wages have remained stagnant since the late 80s.\n\nWhat Bernie is proposing is that we do what the rest of the developed world is doing, and taking healthcare costs off the table of everyday Americans.\n\nIs it free? No. What would happen is our taxes would be raised, BUT everyone will save money for a few reasons.\n\nFirst is because they no longer have to pay for health insurance. As an American you're enrolled as soon as you acquire citizenship. It also eliminates co-pays, because most insurance companies will rarely pay the full bill.\n\nSecond is because of something called the monopsony. A monopsony is a market situation in which there is only one buyer. (In this case the US government is the buyer, in the sellers are the doctors and hospitals and drug companies.) In a monopsony, the buyer has the power to negotiate what they'll pay the seller.",
"Premium is your monthly membership fee. \n\nCo-pay is the reduced fee you pay to see a doctor or specialist if you have the right insurance.\n\nDeductible is the amount that you are responsible for until you hit it, and then insurance kicks in. $5000 deductible means you pay $5000 for everything that year that isn't explicitly covered by a copay, then co-insurance kicks in until you hit the maximum you can be charged that year. \n\nThe maximum is called the out of pocket maximum.\n\nThroughout this entire process you will have to make sure everyone on the fucking planet takes your insurance or it is not covered. You need prior authorization or it will not be covered. You will need to pray to God the claims adjuster got a blowjob that week or it will not be covered.\n\nIf you get surgery you will be billed by separate entities for your lab fees, surgery, room stay, and anesthesia etc. These can all be \"out of network\" and not covered.\n\nInsurance companies will deny claims for anything and everything even if it is covered and then it is on you to sue them. They have billions of dollars and normally this does not work.\n\nRepublicans prefer this nightmare.",
"The Canadian model is a ‘healthcare for all’ model. I am both Canadian and American and have lived in both countries. \n\nCurrently in the US it varies by state and by employer. If you are employed, the system works not too badly if you have a larger employer with a health care plan. Premiums are often shared by employer and employee and paid for monthly. You go to the doctor when you need to. Many plans have co-pays (a fee you pay every time you see a health care worker) and usually there’s a deductible premium (how much you pay out of pocket before full coverage kicks in) and sometimes (often?) there is a cap or limit on how much coverage is provided. If you are not employed or self-employed, it becomes a lot more expensive and therefore the plans tend to not be as good, and more out-of-pocket costs are incurred. And of course there are still millions of people who are not insured at all for one reason or another. We have all heard the reports of people losing their homes or going bankrupt because of uninsured care for expensive treatments for injuries or disease.\n\nIn Canada it varies by province and is similar across the country. If you get sick, you go to the doctor or hospital with no thought about am I covered, or can I afford the co-pay. The original plan was implemented in the province of Saskatchewan in 1962 with the thought that everyone should have access to health care and it shouldn’t depend on the size of your wallet or, in the case of a child, how big your parent’s wallet is. The system works well although sometimes there are waits for specialists. There are public priorities. For example, you never wait for cancer treatment or heart ailments. There may be a waiting list for non-life threatening conditions like hip replacement or herniated stomach.\n\nThe UK is also a ‘healthcare for all’ nation. One way that they are different than both Canada and the US is that their doctors are salaried rather than paid for each service provided. In Canada, public coffers pay for each service. In the US the fees are paid by private (and very profitable) health insurance companies.\n\nThere is certainly more money in the US system than in Canada’s or the somewhat similar UK system. A recent study comparing treatment for recovery of heart attack and stroke victims revealed that the immediate survival rate for the first 7 days after the event was in the US favor. However when a 30 day window of survival was used there was no difference in survival rates.\n\nThe big debate in the US, even when Obama was introducing reforms, is whether private health companies or publicly run agencies manage the model. After implementation, a publicly run system will almost certainly produce financial savings as well as extend health care to those with inadequate coverage. Currently the US has by far the most expensive health care model in the world.\n\nBit of an extended piece. I hope this is helpful."
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1yg4nz | what is the difference between 16:9 and 4:3 aspect ratios? | This is truly an ELI5 because I have seen the technical descriptions and they go over my head and do not address the basic question: 16:9 and 4:3 are, mathematically speaking, identical.
16:9 is not reduced to its lowest terms, but it is the same ratio, you could just as easily say 1,600,000:9,000,000. The ratio should not speak to the # of pixels, film cells, etc., just the dimensions of the frame relative to each other, right? So what is the difference? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1yg4nz/eli5what_is_the_difference_between_169_and_43/ | {
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"actually, 4:3, mathematically, would be 16:12. See, 3 is 75 percent of 4, while 9 is 56.25 percent of 16. So they are somewhat different.",
"It's not the same ratio at all. 4/3 is 1.33, it means it is 1.33 times wider than it is tall. 16/9 is 1.78, it means it is 1.78 times wider than it is tall.\n\nOld CRT displays were 4:3, kinda squarish looking. Most new monitors are 16:9 -- roughly approximating the standard movie ratio (which I believe is actually 1.85, and of course 2.35 is another common ratio, especially for \"epic\" style movies)"
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33g10d | why am i constantly craving food and sweets after being sober from alcohol for an extended amount of time? | Sorry if this is the wrong place to ask. I tried to google, but kept getting a bunch of irrelevant results.
I'm currently 9 days sober from alcohol for the first time in 4 years. I've noticed since I've been trying to get sober, I am constantly hungry. I could eat a huge meal, and about 15 minutes later be hungry again.
Another thing I've noticed is that I'm constantly craving ice cream. This is completely out of character for me as I've never really been big on sweets.
Thanks ahead for any input anyone might have!
Edit: Looks like I found my answers! Thanks for the input in such a short amount of time!
Edit edit: Completely unrelated, but I've also been able to enjoy video games again for the first time in a very long time. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/33g10d/eli5why_am_i_constantly_craving_food_and_sweets/ | {
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"Alcoholic beverages have a lot of empty calories in them that you got used to consuming.\n\nYour body now craves these empty calories because it's no longer receiving what it now knows as normal.",
"Might be swapping one addiction for the other. I have heard of a few cases of folks that deal with the addiction by replacing with something else\n\nFood does numbs some people out",
"Alcohol triggers your GABA receptors, the same receptors sweets trigger. Congrats on staying sober, feel free to indulge in the sweets. You might also want to check out /r/stopdrinking if you haven't already.\n",
"3+ years sober here, and great job--keep at it one day at a time. \n\nas for why sweets, the body metabolizes alcohol into a form of sugar (I don't know what type, I'm terrible at science) so actually having reasonable amounts of sugar when quitting can be really helpful.\n\nsome AA meetings have candy stashes. I did orange juice with a little honey during my first days and it was amazingly helpful. try to use natural forms of sugar, like fresh fruit, but I also would always have hard candies to suck on when I got the shakes. \n\nI wouldn't worry yet about \"trading one addiction for another.\" the body and brain take a while to adjust to not functioning with alcohol anymore. your body is used to having more sugars to metabolize, so trust me, what you're experiencing is very normal!\n\nyou're welcome to PM me if you ever want to chat more about it with someone directly (in addition to the sub recommended by another commenter, I'll have to check that out myself!)."
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8q3buu | how is car air conditioning able to keep one side of the car a different temperature than the other? | Like my car (idk about other cars) as option to set one air conditioning side lower / higher than the other side, would it not just make the car the average of the 2 essentially, wasting energy trying to get both sides to their respective temperature? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8q3buu/eli5_how_is_car_air_conditioning_able_to_keep_one/ | {
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"Its not actually able to keep the sides a different temperature (because it all mixes in the car anyways to equal out), but it will adjust how much air and cooling comes out from vents on each side.",
"It won't ever be the temp it says, it's just changing how hot or cold or how much of the air blowing on that person is. If you let it run long enough the temp in the car would just be an average of the two and wasting energy. The perception of the two people would still be different because the temp or amount of air being blown directly on them would be different. "
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46vhm2 | how can youtube channels like failarmy just use someone else's videos to make compilation videos? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/46vhm2/eli5_how_can_youtube_channels_like_failarmy_just/ | {
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"In the case of FailArmy, they use videos which were submitted to them and when you submit it you certify that you're the copyright owner and give them permission to use it. If other channels use videos without permission then it would indeed be copyright violation and the owners of the videos could make a claim against the channel owner."
]
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[]
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5t0fmh | why do they scan you boarding pass when you buy stuff at the airport? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5t0fmh/eli5_why_do_they_scan_you_boarding_pass_when_you/ | {
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"I think this is purely for tax purposes. Think about if someone is just stopping off to catch a connecting flight and hasn't gone through customs or formally disembarked at the location. Airports sort of exist in a state of limbo; even if you got off the airplane until you go through customs you haven't \"entered the country\".\n\nAs a result you sometimes don't need to pay tax on purchases in airport shops because you aren't in the country yet. These \"duty free\" shops have an interesting position regarding tax law.\n\nHowever what is to stop local people from going through security just to visit the tax free shops? Scanning a boarding pass would prevent the shops from becoming just a regular shopping destination.",
"It's worth noting that this only happens at duty-free shops. You purchase things (usually tobacco, alcohol, or other products that have a fair amount of taxes) without paying said taxes, with the understanding you'll pay them in the country you are going to. Most countries have an amount of product that can be purchased overseas without being taxed, though. Them scanning your boarding pass confirms you are actually going overseas and are not staying domestically (where you would need to pay the tax).\n\nYou can read a little more about it at the wikipedia article for duty-free shops: _URL_0_"
]
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[],
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"https://en.wikipedia.org/wiki/Duty-free_shop"
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3m796y | what is the difference between crystal and glass? | Edit: wow! front page i didn't expect this, thank you for your answers, i now have a much better understanding of both of them | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3m796y/eli5_what_is_the_difference_between_crystal_and/ | {
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"Crystal is a structure where atoms / molecules are ordered in a self-similar repeating structure. Glass is a solid substance when atoms/molecules don't form any ordered repeating structure, and the substance can be heated so it becomes more runny/~~elastic~~ less viscous, and then cooled back into a solid form.\n\nThe difference in the atom/molecule structure looks [like this](_URL_0_). (EDIT: both quartz and pure glass are the same chemical, but quartz is in crystal form and glass is not.)\n\nWhen it comes to *crystal glass*, it is not actually crystal material, but it is just a variety of glass which has lead added in it so it is more shiny. Crystal glass is widely used in decorative objects [like this](_URL_1_) and in fancy glassware and chandeliers.\n\nEDIT: Changed elasticity to viscosity as corrected by u/belortik.\n",
"The difference is at the atomic/molecular level.\n\nA crystal has defined order in it's structure. Sorry for the poor analogy, it's like putting an infinite number of connect 4 games one behind each other with the holes being analogous to atoms. Each \"atom\" in the structure is the same distance from each hole in its respective position, hence the order.\n\nGlass is just a cluster fuck of random atom/molecule arrangements, like a bowl of spaghetti in essence. ",
"Crystal is used in magical spells and artifacts such as orbs and stave catalysts while glass is used in stylistic elven armor. Well technically its not really \"glass\" it just looks like fragile glass when its actually a quite strong clear metal. It can be used in the magical sense as enchanted weaponry however its magical limitations would be on the wood and leather used in the enchanted weapon rather than the \"glass\" itself.",
"Wow, I was just looking this up last night as well. Is it because you saw that gif posted on here of a crystal chandelier being made? That's what prompted me to search.",
"It would seem to me that OP is asking specifically about the differences between crystal glassware, like Waterford or Baccarat or Swarovski and the like, versus plain glass. I think most of the answers so far have ventured far off from that and have gone more into \"crystal\" as a structure. I could be mistaken on OP's intent, however, so perhaps OP could clarify? ",
"What is normally called \"crystal\" is lead glass (glass made with lead oxide added) cut to look like a natural crystal formation. Swarovski is an example of this.\n\nSo the difference is lead oxide.",
"Imagine you have 27 identical Lego cubes. You can now arrange them like a Rubik's cube to create a perfect 3*3*3 cube which is quite strong and holds together well. This is what a crystal is like. Each Lego cube is called a unit cell which when repeated in all directions gives a crystal. \n\nNow imagine you have another 27 Lego blocks, only this time they are all of different shapes and sizes. But they are still Lego bricks and so they still have the characteristic locking mechanism meaning you can put them together in some random order and get a resulting structure, but there are a lot of gaps and defects on the structure. It would also not be as stable a structure as the cube in our earlier example. This sort of arrangement is called amorphous arrangement and is what is found in glass. \n\nThis is the fundamental structural difference. Because of this they have a lot of difference in the properties they exhibit. \n\nE: words and things. \n\nE2: Legos are perhaps not the best building block for this explanation. Lets assume that legos are capable of attaching to each other sideways as well. There. Now the analogy works. \n\n",
"Compared to glass, lead crystal has a higher refraction index which causes it to \"sparkle\" and \"rainbow\" more.",
"Why do so many Hispanic people call all glass crystal? I briefly sold home theater systems and almost every Hispanic customer did this. No one has been able to explain it to me. ",
"Hmm this is on my homework from a geology class today makes me suspicious of why you inquire. ",
"Was this question brought on by yesterday's gif of people blowing/twisting hot crystal? All I wanna know. ",
"Glass is composed of 3 ingredients. \n1. Silica \n2.flux \n3.stabilizer \n\nThe first two ingredients are the same always and the third makes it a different type of glass. A common kind of glass is \"soda-lime\" or \"soft\" glass which uses a stabilizer of limestone. We use this glass for window panes, mason jars, beer bottles, etc. In crystal the stabilizer is lead which makes it \"crystal clear\" instead of having the sort of green tinge to it like soda lime does. In addition to the appearance crystal is more susceptible to damaging by heat exposure than soda lime and also moves at a higher rate. \n\nSource: am a glassblower :)\n",
"Glass is an American slang term for methamphetamine. Usually it implies high-quality meth. The term 'crystal' or 'crystal meth' is equivalent.",
"One is something you snort to stay awake for weeks at a time the other you make windows out of"
]
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3dy3jq | why is the gold meter so high on reddit today? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3dy3jq/eli5_why_is_the_gold_meter_so_high_on_reddit_today/ | {
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"text": [
"Lots of people have bought gold; more than is required to reach 100%.\n\nHere's some extra words to get past the auto mod filter."
]
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[]
] | ||
7zm8kh | why even if you know the outcome of a suspenseful movie scene you still get incredibly nervous | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7zm8kh/eli5_why_even_if_you_know_the_outcome_of_a/ | {
"a_id": [
"dupm6fa"
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"text": [
"Mirror neurons. It's the same reason that the guy in the video pulls his hand away, even though he knows that the hand he's looking at is fake.\n\n_URL_0_\n\nIf you are invested and drawn enough into the movie you're watching, then you're going to be identifying with the character(s) on screen and largely reacting to their environment as if you were experiencing it directly. Your brain pretty much feels like it's happening to you, even though you're just watching it."
]
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[
"https://www.youtube.com/watch?v=MG22iFL-VgE"
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19yt64 | the difference between the current gps system and the new galileo. | I'm looking forward to the next wave of GPS with greater accuracy. Tonight I was reading up about Galileo, but couldn't really find any info on its accuracy, and how it compares overall to GPS which is quite dated technology now. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/19yt64/eli5_the_difference_between_the_current_gps/ | {
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"GPS is under the control of the US military. They can drop it's accuracy or disable entirely it on-demand. Galileo don't have that \"feature\".\n\nGalileo also has a new feature - search-and-rescue transponder, so if you can see the sky then you don't need cell phone coverage to send a distress signal, just a device that can send a signal that the satellites will pick up and that they could send back to a nearby SOS callcenter or similiar.\n\nAlso, since it is newer the protocols and accuracy can be better, because they don't have to be compatible with old hardware that don't support the improved methods for higher precision. All the devices for it will be able to use the better methods. I don't know exactly how much better it is, but I can't imagine it wouldn't have at least 10x the precision, at least it should be possible.",
"From my limited knowledge there are only a few changes realistically to the end user from current GPS (not GLONASS) to Galileo. \n\nOf course, there are a litany of other technological changes and improvements that I won't mention, but the basic main points can be summed up into 3 key points:\n\n1. Improved civilian accuracy from roughly 3 meters, to about 1 meter or less.\n\n2. They wanted to create a neutral, accurate GPS system for any country or person to use. Current GPS cannot be used as such and is limited in many ways. (This drew a lot of ire from US because of the way Galileo was designed, the US couldn't jam it without jamming its own GPS. Galileo has since been redesigned to use a different frequency so the US can jam it if need be to deny other countries from using to direct ICBM's and other targeted weapons using Galileo. Also, Galileo will remove the ability for the US to enact Selective Availability, which basically allowed the US to block GPS usage to certain regions and countries at will using software/the signals themselves without jamming that frequency (during war efforts mainly.)\n\n3. It provides a dedicated search and rescue system that can be activated anywhere on the planet from certain devices that will be relayed to a Rescue Co-ordination Center, which will then send support and aid if possible. This system also offers the unique ability to send a signal back to the original person who requested aid letting them know their search and rescue request was heard and is in process.\n\nHope that helped, and if not maybe someone with a little more knowledge can weigh in.\n\n"
]
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1p9crw | what happens if you go up or down in space? | Say you had a Starship, can you fly down or up in Space?
What would happen?
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1p9crw/eli5what_happens_if_you_go_up_or_down_in_space/ | {
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"Up and down don't really mean anything if you're in microgravity. The terms become largely irrelevant, with up meaning nothing more than \"whatever is above where my head happens to be\". ",
" > Say you had a Starship, can you fly down or up in Space?\n\nYes. Or rather, you can fly in any direction you want, but \"up\" and \"down\" are entirely meaningless when there's no gravity to define them."
]
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2qyi5x | why is the ai in most videogames so terrible? | This is most glaringly obvious in RTS games but in most games as a whole the AI frequently makes the stupidest possible choices, misses opportunities, and generally behaves like a toddler being handed Chinese algebra.
This lack is often addressed by giving the AI bonuses and perks (cheating) that offset the tactical stupidity but this generally doesn't make the game harder by virtue of the AI making better choices it just makes it harder because the player is at a greater handicap.
In more recent years it's gotten slightly better but the AI still seems fairly locked into a standard series of moves that, while clever, are formulaic in that if you react in an unorthodox manner the AI can't cope.
So why is this? Is programing tactically sound computer opponents just that difficult or is it something that takes more work than most devs are willing or able to invest in a game? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2qyi5x/eli5_why_is_the_ai_in_most_videogames_so_terrible/ | {
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"Yes programming tactically sound computer opponents is really difficult. Actually not really, programming a computer opponent that will almost always beat a human player is actually easier than making one that's just OK. What's near impossible is making an AI that plays like a human, particularly one that makes mistakes a human would make (making one that makes correct decisions is easy enough). So basically, programmers have to try to find the balance. If they make the opponent too easy, the game isn't fun, if they make it too hard, the game isn't fun (for most people). The easiest way to make a moderate computer opponent is to make one that plays perfectly some percentage of the time, but makes semi-random mistakes some percentage of the time. Looking at these mistakes in a vacuum makes them seem like really stupid moves, but overall (if the programmers did their job well) it should balance out to a skilled but not too skilled opponent. This strategy is most obvious in some chess sims. You put the computer on intermediate, and at some point in the game, it might move it's rook to a square where you can capture it with no repercussions for no reason, but then it'll still beat you.",
"I think I can answer this as a hobbyist game developer:\n\n.\n\nThe reason why AI seems often to do something idiotic is because it isn't easy to write a perfectly logical system that can respond to every single variable there is without causing internal lag and still appearing to be a human player with thoughts and logical intuition that senses the world like you do. Making a 'human' AI is really tricky.\n\n.\n\nImagine your standard RTS. Imagine all the information that you, as a player, must process in order to win the game. Imagine the resource management, the unit placement, you're thinking what your opponent is doing and how you are seeking out weaknesses in both your base and his. You're trying to prevent every single thing and every single scenario that might arise. This is easy for you, you can take in, process and improvise in every situation. You're a human that has impulse and can act in suprising ways to cope. \n\nThe AI isn't any of those things.\n\n.\n\nImagine if you would have to ask yourself several hundred \"yes/no\" questions for everything. that you had a thick rulebook that would dictate everything that you'd do based on how you answered those yes/no questions. This is the reality of the AI. Everything the AI does it 100% predictable. if we assume for simplicity that the AI never uses random functions you could set up a scenario and for every single run you could predict with 100% accuracy what the computer will do. Why? Because that's how code works. It asks itself a million true/false questions and reacts based on the variables it has present at that moment. It can't look at the playing field and go \"ok, he's coming in from the east, retreat my army and meet it from the front\". That's not possible, except in a strange back ended fashion. \n\n.\n\nProgrammers such as myself try to limit the number of questions and do this more efficiently. Try to put up state machines where the AI tries to seek out what it is doing at that moment, what it should be doing, what should have more priority than something other thing, try to increase the amount of \"smartness\" of the AI by giving it more options to react with, give it more variables or give it more logical things. But given that the player can literally create an infinity amount of different scenarios it soon becomes impossible to create an AI that doesn't at some point does something completly retarded. The problem is that if we just go for the \"AI is so smart it always wins\" is horrible because it will feel like the computer is cheating. It will be too smart. The main issue is making an AI that can fool the player into believing that it is a real human. Imperfect, but smart. That balance is the holy grail of AI design.\n\n.\n\nTHe smarter AI you make the more time you have to spend programming it, and the less time you get to do something else. A professional studio would try to balance the \"The AI is an idiot\" and \"Ok, we have to start working on networking, and flesh out bugs, or complete the stealth engine\" or whatever. often the AI ends up in a \"Good enough\" state, where it might be an idiot often, but it also is smart enough to challenge the player a bit so it feels like it can think.\n\nIt's a constant struggle, and we're doing our best, but sometime creating something that appears to think when really it's just following 100% strict and defined rules.\n\n.\n\n***TL;DR: Because making AI that can respond to every illogical situation the player puts it into when it is a perfectly logical and limited system in a limited time is really really complicated.***"
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4ok067 | why do blood pressure cuffs slowly release air? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4ok067/eli5why_do_blood_pressure_cuffs_slowly_release_air/ | {
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"To use a blood pressure cuff, you listen for a sound to start and stop. This comes from the blood vessel, above a certain pressure it does not make the sound. So to take blood pressure, you air the cuff up (called a sphygmomanometer) higher than blood systolic (when their heart is squeezing) pressure, wait until you hear a sound, and the pressure where the sound starts is the systolic pressure. Air continues to leave, and when the sound goes away, you passed the diastolic pressure (the pressure when the heart is relaxed)."
]
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3c345s | why isn't the drought in california being considered desertification? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3c345s/eli5why_isnt_the_drought_in_california_being/ | {
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"text": [
"Drought: Shortage of water\n\nDesertification: \"Desertification is a type of land degradation in which a relatively dry land region becomes increasingly arid, typically losing its bodies of water as well as vegetation and wildlife.\"\n\nHowever, note that on [this map](_URL_0_) the whole area is marked as extremely vulnerable to desertification. Not being there (or in fact, anywhere on that continent), I cannot comment on if the definition of desertification already applies or not."
]
} | [] | [] | [
[
"https://en.wikipedia.org/wiki/File:Desertification_map.png"
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eqn2yj | why does 20 pounds feel like a lot when carried, but when you gain 20 pounds you don't notice the weight? | I'm sure there's something about distribution and center of gravity or something... I'm just curious why carrying weight outside the body feels so much heavier than when we gain weight and carry it inside the body? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/eqn2yj/eli5_why_does_20_pounds_feel_like_a_lot_when/ | {
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"text": [
"Primarily because weight gain is a fairly gradual process. The even distribution across the body helps, but you'realso not getting the 20 pounds at once.",
"I assume a lot of it has to do with when you gain weight, it’s a gradual progression over time. You’re not 20lbs heavier one morning when you wake up.",
"Both because weight gain is gradual and because it's spread out across your body evenly, as opposed to just strapping the weights on at a given spot.",
"Your muscles get stronger to make up for the extra 20 pounds when it’s part of your body weight all the time.\n\nIf you carried 20 pounds (especially in a well-distributed way instead of holding it in your hand or something) **all the time** you would eventually get used to it and stop noticing."
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2417oa | why are modern tank guns smoothbore if rifling is more accurate? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2417oa/eli5why_are_modern_tank_guns_smoothbore_if/ | {
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"Not all tanks use smoothbore, but the ones that do use fin-stabilized rounds. The fins provide the necessary stability that the rifling would've. Basically after the shell fires, the outer casing flies off, revealing the smaller round. [Here's](_URL_0_) a picture of one in action."
]
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"http://upload.wikimedia.org/wikipedia/commons/2/26/Sabot_separating.gif"
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5bun34 | how does one have 'bad' depth perception? | And what can one do to improve it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5bun34/eli5_how_does_one_have_bad_depth_perception/ | {
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"There are more than five senses, depths perception is one of them.\n\nWhen you reach out and pick up a pen off the table, you brain works out how far away the table and the pen are from your hand, and moves your hand the correct distance to pick up the pen in one fluid movement. Your brain does this by comparing the two images your eyes send to it and converting them to 3d\n\nTry this, cover one eye, and have someone throw something (soft) at you, your depth perception will be totally off, and catching it, if you manage at all, will take more effort that usual. \n\nTry it, let me know if you can see a difference\n\nAs for improving it, I would guess that its the same as virtually everything else in this life: practise."
]
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9nrer9 | how do old songs like message in a bottle or tv shows like friends get remastered when the equipment itself was used during the time it was recorded or filmed? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9nrer9/eli5_how_do_old_songs_like_message_in_a_bottle_or/ | {
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"The studio recording equipment, eg reel to reel tape and studio cameras make a much higher quality first generation copy of the source material. It's the mixing process and delivery formats that suck.\nDigitize the source material and re edit using modern equipment, you then get something that looks and sounds better on today's consumer equipment. "
]
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ab9nh5 | why does your jaw randomly lock and hurt like hell when you yawn sometimes? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ab9nh5/eli5_why_does_your_jaw_randomly_lock_and_hurt/ | {
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"Your muscles are cramping. It can come from dehydration or lack of proper electrolytes. Drink more water. Eat foods with calcium, magnesium, and potassium.",
"Stress, teeth grinding, over stimulation of the jaw muscles, and arthritis can all cause the jaw to randomly lock. I get it quite often. It's likely a stress response for me. I guess it could be from cramping due to dehydration, but not if it happens all the time. Sometimes it can be addressed with medication, therapy, or a few visits to the dentist. It isn't life threatening or really all that harmful in the grand scheme of things, but I know it can suck!",
"Partial dislocation of the **temporomandibular** joint."
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bxd5y2 | how does a negative number modulus a positive number work? | With positive numbers its easy. The remainder is your answer.
e.g 5 divided by 3 = 1 and i have a remainder of 2. Therefore 2 is my answer for 5 % 3.
However how the heck does -5 mod 3 = 1? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bxd5y2/eli5_how_does_a_negative_number_modulus_a/ | {
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"Think of modulus like the numbers on a clock. If it's midnight now, then 15 hours from now it will be 15 mod 12 = 3 o clock. If it's midnight now, then 8 hours ago it was -8 mod 12 = 4 o clock.\n\nBasically, in modulo 12, twelve *is* zero. So -8 is the same as 0 - 8, which is the same as 12-8, which is 4.\n\nIn general, you can take the modulo of a negative number by *adding* a multiple of the modulus, just like you usually find it by *subtracting* a multiple of the modulus.\n\nFinally, if you still want to think of it as division-remainder, try these steps.\n\n-5 / 3 \n= -3/3 + -2/3 \n= -1 remainder -2 \nThe remainder is -2, which means \"two less than zero\". \nIn modulo 3, three is zero. So two less than zero is 1. \n-5 % 3 = 1.",
"In order to add to the confusion: You think of modulus as an operation right now, but number theorists in mathematics tend to think of it as a relationship called *congruence*.\n\nFor a number theorist, the question what is -15 mod 12 doesn't really make sense. However, he will say that -15 mod 12 = 9 mod 12, i.e. under mod 12, -15 is the same as 9. But it is also the same as -3. You just use a symbol to represent the concept."
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3u3x0z | why are the depths of the ocean dark? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3u3x0z/eli5_why_are_the_depths_of_the_ocean_dark/ | {
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"Because there is no light there. There are billions of tons of organic matter, dust, dirt, etc. In the oceans and water itself is not perfectly transparent either so once you go deep enough, all of the light from the sun has hit something or other and doesnt reach any deeper.",
"The water absorbs the light, red light is more easily absorbed than blue light, but once you get down to 200m, there's pretty much no light at all.",
"Light can't penetrate water forever. the long wavelengths get absorbed first, which is why the ocean looks mostly blue.\n\nBut the deeper you go, the less light reaches there and you get darkness."
]
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1wtu9r | why do you drill horizontally when fracking? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1wtu9r/eli5why_do_you_drill_horizontally_when_fracking/ | {
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"text": [
"IIRC, the shale veins that we get are getting the oil from are quite thin but cover a huge area. As such, just drilling straight down will yield high waste vs if you go horizontally through the shale. "
]
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3pdc3y | what would it take to make 4k hd mainstream? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3pdc3y/eli5what_would_it_take_to_make_4k_hd_mainstream/ | {
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"Probably much [larger walls or much smaller rooms](_URL_0_) than most American homes have. \n\nFor people with 20/20 vision, one must sit quite close to the set to notice the additional resolution, closer than [THX's narrowest reccomended screen angle](_URL_1_). Even with blu ray adoption has been much slower than with DVD suggesting that most Americans don't feel much pressure to upgrade resolutions even to 2k. ",
"More bandwidth and cheaper manufacturing processes.\n\n# Bandwidth\n\n4K takes a lot more bandwidth than 1080i/p video which. Cable and Satellite TV providers already have a limited amount of bandwidth available for carrying television broadcasts and there isn't enough bandwidth available to carry every channel in 4K unless they compromise by cutting down the number of channels they offer.\n\n4K also takes a lot more bandwidth online, so people need to have broadband internet services that can support high-bandwidth video streaming (the bandwidth required for 4K video can be as much as 4x the bandwidth of an equivalent 1080p video). This also costs the content providers (e.g. Netflix) more in terms of their bandwidth costs and means that ISPs will need to perform more upgrades to their infrastructure to support higher capacity links between them and their customers as well as higher capacity links between them and Content Delivery Networks as well as IP Transit networks.\n\nIn terms of storage space, 4K video requires much larger file sizes (e.g. requires Blu-Ray or equivalent discs with much larger capacities) in order to maintain the same level of visual quality (as compared to a 1080p version of the same video).\n\n# Manufacturing Processes\n\nIt currently costs significantly more to produce and obtain broadcast quality 4K cameras and related video (and transmission) equipment and unsurprisingly it also costs significantly more to purchase a 4K TV as compared to a 1080p TV. \n\n4K/UHD has already started to become mainstream, but the cost is still higher and it will take time for people to adopt. As more and more people and manufacturers adopt 4K/UHD standards, the per unit costs associated with manufacturing will decrease as the result of *economies of scale*. \n\nThat is to say, greater demand leads to lower manufacturing costs and usually lower consumer prices, so the more people become interested in 4K, the cheaper it will become (as is the case for basically any technology).",
"4k requires lot more bandwidth agreed, but we're always getting better at making higher speeds available, so the problem will solve itself. 100 MBPS a decade back was like a wet dream for all, a lot of people have it now. Same with manufacturing costs, technology gets cheaper and cheaper by the passing day.\nThe factor which I think is limiting 4k technology is that very few people are using devices that record 4k. They are quite expensive, and the average person doesn't see the need to spend so much as of now. As and when the cameras get cheaper, more people will buy , just to have a have a better device, and then eventually all the other factors will give in.\nIts the same story that happened with 1080p."
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6j0boz | why, when playing a song repeatedly, do we tend to get tired of hearing it, then can enjoy the song again after a break? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6j0boz/eli5_why_when_playing_a_song_repeatedly_do_we/ | {
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"The general theory for this is that our brains thrive from predicting. This is why you might not like a song initially, but after a few more listens you start to love it because you can predict where the song will go next.\n\nBut it also works both ways; listening to a song hundreds of times results in diminishing returns of satisfaction from predicting it, because it's become 'hard wired' into your brain. Then you take a short break, so you can enjoy the song again because you can't remember all of it anymore, and your brain enjoys trying to predict what will happen next again.",
"Three important functions of our brain \n1. detect patterns\n2, predict outcomes\n3, detect change\n\nAll of these help us to recognize / avoid danger\n\nOur sensory systems are designed to respond when input changes- for example, when the thermostat of an air conditioner goes on, we hear the hum. \nAnd then when it goes off, we hear the silence. \n\nThese responses to change need to be noticed- since changing conditions are potentially dangerous\nAfter a minute of hum/ silence the receptors adapt and shut off. \n\nOn a higher level, when we listen to music or see art, we initially make predictions about what will come next. When the music or art is unfamiliar, the next earful or eyeful is a surprise. So we attend closely . \n\nOnce the information becomes familiar, we can predict its entirety with a brief glance or short sample of sound. It has no novelty and is becomes less interesting. Even just seeing the title on a playlist evokes the memory of the entire composition. We apply our attention to new information. \n\n(Source: _URL_0_)",
"I don't listen to the radio much, so I mainly hear new songs and artists through my girlfriend or on weekends at a bar.\n\nIt's so frustrating hearing a song that has been out for a month and being told, \"This is so old, turn it off.\" Then they play Sweet Caroline or Wagon Wheel and the crowd goes nuts...\n\nA song isn't old because it's over played. The song is old to YOU because YOU overplay it/don't switch stations or press next on your playlist! ",
"An equal question is why some songs don't impress us initially, but can grow on us after repeated hearings. I think the predictability plays are part here in opposite ways.\n\nBack in the day The Rolling Stone would get prerelease's of albums to review them. Some of the best selling albums in history received poor reviews. Many of them are now on The Rolling Stones top 500 albums of all time.\n\nThe Beatles often argued about future iconic songs and whether they should be put on an album because the guys that didn't write the songs thought it was subpar. (e.g. As my guitar gently weeps)\n\nAlso many super hits sit on the shelf for years even tho many hear it and pass on recording. The country song of the year Whiskey lullaby was like this. The Hallelujah Course written and recorded by Leonard Cohen was ignored for years by more mainstream recording artists.",
"not for me sometimes wen i am in the mood for some mindless grinding in a game. \nI put the same son on on repeat * and grind / kill mobs in coordination with the beat of the song * \nMy record is like 14 hours straight up one song on repeat while leveling from lvl 1 to 60 through mob grinding in wow \n",
"Doesn't happen to me, I usually start listening to a song I like and keep playing it all day, because there are certain parts of the song I like most and so I just to listen to them constantly."
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b36zez | why is it that the more your routinely exercise the more quickly and more profusely you sweat. | For more clarity, I’m not talking about the duration of a single workout, I’m referring to exercise over and extend period of time. I find that, especially with cardio exercise, the more routine I am the more I sweat with each workout. In the beginning I can work out so hard I feel like I’m going to throw up and maybe end with a damp shirt. Then two to three weeks later I can perform the same workout and not feel nearly as exasperated but my shirt will be drenched and sweat will be dripping off my nose. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b36zez/eli5_why_is_it_that_the_more_your_routinely/ | {
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"Once you do enough heavy exercise, your body will recognise that there will be a need to sweat plenty to keep up. However, your body doesn't know when you will do light exercise v. heavy exercise. \n\nSo it will just assume you are going to do heavy exercise and sweat plenty accordingly."
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rcvjk | why computers are constantly becoming more powerful | And why couldn't we have the computers of 2012 in 2002? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/rcvjk/eli5_why_computers_are_constantly_becoming_more/ | {
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"The idea that computers are becoming more powerful year on year, and in fact, doubling in power every two years is known as [Moore's Law](_URL_0_). Moore's Law has been pretty much accurate since the early 60s.\n\nThe reason for this is that transistors, which are the most important building block for making computers are gradually being able to be made smaller and smaller, as the technology used to create them gradually improves and becomes cheaper.\n\nFor example:\n\n* An Intel Pentium 4 processor built in 2000 has 42,000,000 transistors, each of which are 120 nanometres across.\n\n* The much newer Intel core i7 processor built in 2007 has 731,000,000 transistors, which are just 45 nanometres across.\n\nYou don't need to worry about how big nanometres are (they're really, really small), but you can see that transistors are getting smaller, and processors are gaining more transistors. Having more transistors translates directly into having more powerful computers (of the same size, at roughly the same price).\n\nThere's lots of speculation about when Moore's Law will stop working. There is likely to come a point where it's just not possible to make transistors smaller, and it's likely that this will happen during this decade. *(non-li5 note: quantum physics starts getting in the way)*\n\nThe other way to have more powerful computers is to combine lots and lots of processors together to form supercomputers, which you can do without making the transistors themselves smaller. But since these get very big and expensive, and take a lot of power to run, they're out of most people's range."
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2bze17 | what is it when everything just looks really bright/your eyes white out for a moment, then goes back to normal? | Just out of the blue, during some random moment, very thing becomes super bright, and I feel off balance. (hard to walk in straight line) Lasts to for 3 secs at most | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2bze17/eli5_what_is_it_when_everything_just_looks_really/ | {
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"What is it?\nTime to see a doctor.",
"It's called a [Greyout \\(Whiteout\\)](_URL_0_). Essentially, it's lack of oxygen to the brain. \n\n**Causes are:**\n\n* Shock, such as Hypovolemia, even in mild form such as when drawing blood.\n* Suddenly standing up (see orthostatic hypotension), especially if sick, hungover, or suffering from low blood pressure.\n1. Positive g-forces as experienced by pilots or roller coaster riders.\n* Paradoxically, hyperventilation: self-induced hypocapnia such as in the fainting game or in shallow water blackout.\n* Overexertion\n\n**Source**: I used to get these when I first started playing Football in the hot, Arizona sun."
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8cjyiu | why are heart shots instant kills? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8cjyiu/eli5_why_are_heart_shots_instant_kills/ | {
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"Because as the heart pumps, it can no longer pump the blood throughout the animals body as it is supposed to. The blood gets pumped out through the bullet hole, meaning that fresh oxygen-laiden blood cells do not reach it's brain, and it will then either die due to blood loss or lack of oxygen to the brain, though almost every time it will be the former.",
"Your brain doesn't immediately die when that happens. Instead, as soon as the blood pressure tanks because you've lost contractions, you lose consciousness and pass out. This is because your brain relies on a certain concentration of oxygen in your blood. If there's not enough oxygen, you go unconscious. You can't stop this. \n\nYou can be revived if you return oxygen to the brain fast enough, but you don't have much time. Plus, there's no way you can get a repair on the heart that quickly. Unless you get shot on the operating table, you're losing so much blood that you likely can't be saved. ",
"That’s the central place of blood transferring. If that’s gone, you can’t pump blood. That means we lose conscious. We don’t actually immediately die the second the heart is gone, we live for like 30 seconds afterward\n\ntl;dr : we don’t ",
"You're in the shower, someone shoots your water pump, how quick does your shower stop? Almost instantly. Your body, all of your organs, need pressure to operate. When you blow the pump the pressure drops instantly and you go unconscious and then dead 💀. "
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5684ai | why can you daydream while driving and still make the correct turns or just not die in general? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5684ai/eli5_why_can_you_daydream_while_driving_and_still/ | {
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"Random guess, based primarily on Charles Duhigg's work: Most of our decisions are subconscious, to the tune of 90+ percent.\n\nIf traffic is predictable enough for you to carry on a conversation, then it's predictable enough to day dream.\n\nI would imagine that the same triggers that prevent you from talking while performing a difficult merge onto a busy freeway (Dallas, Boston, or Las Vegas anyone?), would snap you out of your day dream.\n\n(Sidebar: The same effect prevents you from walking while doing complex math. Try it.)",
"Your subconscious doesn't need you to make decisions and move, but it will need you to make smart decisions and to move quickly!",
"Instinctual tasks, whether provided by nature, or deeply learned become \"nearly automatic\" to prevent mistakes.\n\nThat old adage about walking and chewing gum? If both tasks required your actual attention, then you'd suck at either and doing both would be impossible.\n\nSo things like driving, or walking for that matter, involve a series of tasks such as \"continuous threat assessment\" and \"spatial placement of objects\" (how far to the corner, pot hole, tree branch I have to duck, small child with ball) and control tasks (go faster, go slower, don't fall off my feet).\n\nSo any complex task, including even seemingly simple things like typing, will be examined during initial learning. As you learn it, it will become more and more automatic and therefore faster and less error prone.\n\nAs the automaticness takes over, the higher functions that were needed to learn the task are freed up to do other things.\n\nIf you place no demands on your higher functions they'll start just bubbling up thoughts and feelings the same way an engine idles when you make no particular demands of it.\n\nThe thoughts tend to be very \"dreamy\" on average so that they don't use up any of your real-world real-time necessary processes. It's easy to drive while thinking about your ideal vacation, it's harder to drive while mentally measuring your yard and converting it to board feet of lumber... because your automatic processes are using your spatial sense to control the car. I mean you _can_ do it, but it's not as easy.",
"multi tasking and prioritization. You have many things you're doing even just sitting still in a chair reading this. You can't rightly call them fully automatic because you can take over control at any point, stand up, look away, read the words backwards, hold your breath, etc but for the most part you don't need to concentrate on them. \n\nWhen you drive and kind of go into auto pilot, you are still very much in control of the car, but you aren't giving driving your full attention. You're keeping between the lines, feeling the road and your speed from vibration, sound, g-forces, and any sudden changes, red brake lights, noise, anything which your mind is half way scanning for, if it happens you snap back to attention. \n\nWhen you do something conscious for long enough and you get good enough, and have had enough practice, you can do it without too much mental effort. \n\nThink about when you first started driving, you probably looked at the road right in front of your car, you were super conscious of how far away from the curb you were, whether you were in the center of your lane, people riding your ass made you nervous, and if you knew you had to change lanes in a mile to exit, you would change lanes well ahead of time so you didn't feel rushed. \n\nBut over time you started feeling in control and comfortable enough to take your eyes and unglue them from the road right in front of you, and you started looking further ahead, you started being able to keep the car in the lane without looking to the side, and you started being able to judge your speed based on noise, visual cues, and bumpiness, until you reached a level where you could drive in a relaxed manner and scan the road for miles ahead, and occasionally check your surroundings and keep track of where other cars are in relation to you. Eventually that's 2nd nature etc. \n\n\nBasically TLDR you can drive on autopilot because you are so comfortable driving that you don't need to give it constant attention, leaving time for day dreaming, enjoying the sites, singing along to that one song you are embarrassed to sing along to, all that good stuff. ",
"Everyone achieves the level of grandmaster daydreamer early to mid teens, during puberty. This allows you to fill out your talent tree, one of the perks is daydreaming while driving. Each point raises your skill 20%. Put the 5 points in and you can daydream and drive with no additional risk.",
"If you think of consciousness as a stage with a spotlight, there are some things in the bright spot (these are explicit to you; when you're watching a show intently, it's in the bright spot) some things in the darkness (these are implicit to you; like the fact that you're sitting on the couch). \nOur consciousness is attending to all of these things at the same time, but some things we attend explicitly and some we attend implicitly. Your awareness of your driving is in your implicit knowledge, rather than in the \"bright spot\" of your consciousness. You can attend to your driving implicitly because driving involves your body schema rather than the more \"cerebral\", or explicit part of your consciousness. The more you practice, the easier it becomes to drive without explicit awareness. It's like pitching a baseball: the more you practice and get it into your body schema, the less you have to think about getting it right.\n\n(Gallagher, Shaun & Zahavi, Dan (2007). The Phenomenological Mind: An Introduction to Philosophy of Mind and Cognitive Science. Routledge.)"
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12b01u | mathematical induction | I really cannot wrap my brain around it.
For example if you have:
Sn = n^2 (where Sn denotes the sum of the first n positive numbers, eg: S3 = 1+3+5 = 9)
You can prove that any for any random number K its true, and you can also prove K+1 is true, but how from that do you come to the conclusion that every single value for K is true? I know HOW to do it, I really don't understand it though. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/12b01u/eli5_mathematical_induction/ | {
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"If it's not true for every single value of K, there must be some *specific* value of K for which it is not true. But what value of K can you not reach by successively adding 1?",
"You have to prove it is true for a *base case*... the induction has to start with some specific value... that together with the demonstration that *one true case leads to another true case* is the basis of the induction... so it is NOT true for every single number, but it is true for every single number *starting with a base case*",
"This is in the language of 5 years old, I suppose: \n\nThink of a lined up dominos. You want to know if you tap one(any one), to see if the rest that follows it will fall or not. \nSo first, you test the \"base case\", which is the first one knocking over the 2nd one. Once you prove that. Ok, good. Let's move on the proving 2nd one knocking over the 3rd one. and so on. But that's exhausting. So let's prove the Kth one knocking over the (Kth + 1) one, where K could be your first (K =1), or (K=2) or whatever. \n\nSo if you're able to prove Kth knocks over Kth+1. And there is no limit of what K could be. Oh my goodness! You have proved ALL cases. \nBUT, you have to prove K = 1 first, combing with the base case to prove the whole thing, since the whole damn thing might not even fall after the first domino; in some sense, theres no point proving Kth knocks over Kth+1. \n\nSo that's why you first prove the base case, then the general case. That's how I understood it. \n",
"You have it wrong. Induction doesn't start by proving for \"any random number\", nor does it prove that for \"every single value\" the statement is true.\n\nYou prove it for a base case, which is often 0 or 1, and by also proving it for `k + 1`, you know it's proven for 2 (e.g., k = 1). Since we know it's proven for two, you can induct that it's proven for 3 (e.g., k = 2). Now 4 (e.g., k = 3), 5, and all the other integers up to infinity. If you want to prove it to negative infinity as well, you also prove for `k - 1` and induct similarly down to negative infinity.\n\nInduction can *not* be extended to uncountably infinite numbers like the reals or complex numbers.",
"Suppose we have a really long staircase, made out of a bunch of steps. Then we spoke to the man who made the staircase and he said that the step directly above each red step is also red. Also, we know that the second step is red.\n\nIs the third step red? Well yes, step 2 is red and step 3 is right above it so is also red. Is step 5 red? Is step 100 red? Yes, all the steps above step 2 are also red.\n\nIs step 1 red? We only know the each red step has another red step above it, which doesn't mean that every red step has a red step before it. As such, we can't conclude anything about step 1 from what we've been given.\n\nMathematical Induction is just this logic applied to other situations. Say we have a set of statements(and we label each statement with a positive integer). If we can show that the statement K+1 is true whenever statement K is true and also show that one of the statements is true (let's say it's statement N) then we've proved that every statement after N is also true."
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217e0d | why don't popular rappers diss each other anymore? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/217e0d/eli5_why_dont_popular_rappers_diss_each_other/ | {
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"Don't they still? I don't know about anything especially flagrant, but I still hear one rapper talking some smack about another every once in a while.",
"Kendrick Lamar just called all the new school rappers out a few months ago. I wouldn't classify it as talking shit but it's something?",
"Hip-hop has gradually drifted away from the hardcore, gangsta driven style that was widely popular during the 1990s and early 2000s. During those eras, rap was a lot tougher and there was a heavier emphasis on being 'real' -- staying true to street culture, or at least being truthful in your lyrics. Because of that, hip-hop feuds had a tendency to unravel into violence. Artists' had a responsibility to prove that they were as true to their image as possible so as not to be exposed as a fake. During that climate, being exposed meant that sales would slump and your career could be ended. \n\nHowever, listeners gravitated away from that culture as alternative and \"middle-class rap\" -- popularized by guys like Kanye West, Outkast, Kid Cudi, and Drake -- became a mainstream staying power. The climate changed, and thus so did the industry. There isn't an incentive to being as tough as possible nowadays. Yes, there's sub-styles like Trap and Chicago Drill that embody the 90s culture of hip-hop, and violence sadly does still occur, but the regular hip-hop listener got sick of the elements of that era. \n\nIt should be noted that the stereotypical \"DAE 90s underground hip-hop\" backpacker is not typically wholly conscious of everything that happened during the Golden-Age, and just aimlessly points at present-day mainstream hip-hop as the culprit to every problem in society: money, drugs, sex, etc. \n",
"When Tupac and Biggie got shot, the industry realized that there were consequences to selling beef.\n\nA lot of young people get *really* emotionally invested in their music and let it define them. Punk, Metal, Country, Rap - the music of poor young men with little futures - all tend to get people dedicated to being \"hardcore\". When your heros are talking about murdering people that insult them & other musicians insult them, that's just lighting a fuse.\n\nThe industry has realized that there's millions to be made selling rap albums. Millionaires have gone beyond the lifestyle of no hope, no future & nothing to live for - why would they want to make music that's going to get their ass shot?",
"It all depends on the level you're talking about. For mainstream acts, it's just not worth it to attack each other. It's business, and fights only occur when they can serve to increase record sales. On the underground scene, people still do all the time. Rap and, most specifically, the 'drill' genre of Chicago Hip Hop is used to declare gang affiliation and challenge other people. Lil Jo Jo was a rapper recently gunned down in part due to his BDK video. BDK is an acronym for Black Disciple Killer, Black Disciples are the gang the Chief Keef is affiliated with.",
"I kind of miss the shit talk too. If you turn on the radio it's lovey dovey bullshit. If you need a fix of good shit talk, Ghostface Killah assembles a [list of softest rappers](_URL_0_) every so often.",
"I remember when 'gangsters' would not ever admit to eating pussy.\n\nThings have really changed..."
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24jkgy | why are some babies born with a full head of hair and others born bald? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/24jkgy/eli5why_are_some_babies_born_with_a_full_head_of/ | {
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"Might have something to do with how developed they are? Also interested in hearing about this.",
"No one really knows the true reasons, but a lot of believe it has to do with maternal horomones and genetics. there are other theories about darker skinned people being more likely to have babies with hair. I'd guess that it probably has something to do with the mothers diet before and during pregnancy.",
"I don't believe anyone *really* knows. Some say it's genetics or maternal hormones. Also, the hair on a newborn will (often) shed anyway within the first six months, due to the hormones the mother was providing dropping off (usually).\n\nInfants then go through a [telogen](_URL_0_) phase where there becomes an even more noticeable loss of hair. \n\nSo, in the end, it doesn't matter. As far as why it happens? Genetics? Ethnicity? Hormones? A mixture of things, just as plays into a person's height, I guess.\n\nHaven't been able to find any good, scholarly articles to provide, but I'm sure someone can come along to do so.",
"\nWhen a baby is inside the womb, it receives hormones from the mother. Depending on the mother the baby grows hair or does not grow hair using these hormones.\n\nLike other characteristics, the amount of hair depends on genetics and even ethnicity. \n",
"One of my friends took prenatal vitamins every day which made her hair grow like crazy and when she had her baby he had a full on natural faux hawk and luscious thick hair. So the diet probably is the cause. ",
"To piggyback on this, why are some babies born with a hair color different than when they grow up? My parents both have brown hair, I've had brown hair since about 2 or 3, but I was born with blonde hair.",
"Most, if not all ethnically pure Native American babies are all born with a full head of thick, black hair.\n\nSource: Am 100% Navajo",
"what about infant born with all their teeth",
"Fun fact: The amount of hair at birth is correlated with heartburn experienced during pregnancy. An old wives' tale that was shown to be true!\n\n_URL_0_",
"Chinese babies all pop out with a lot of hair. My own baby included. My coworkers look at my baby and the first thing they say isn't the typical \"your baby is cute.\" That's the second thing they say. The absolute first thing they say every single time is:\n\n\" oh my goodness your baby has a lot of hair!\" Every Chinese person I have talked to says my baby is a normal Chinese baby with a normal amount of hair.\n\nEvery white person acts like my baby is a freak of nature for the amount of hair she has. In hindsight, I have looked through my Facebook friends. All the white babies are all bald, and the Chinese ones have tons of hair. \n\nSo yeah.... genetics. I suspect it is the east asian EDAR phenotye which I am homozygous for(23andme confirmed). I am surprised no one has pointed out this gene yet. There is strong interest in this gene in the scientific community as it is one of the most highly selected for genes in the east Asian populations, and along with lactase tolerance, is also evidence for recent human evolution(past 10000 years or so)",
"It's just about genetics, dna. Some people have already lots of body hair when they are 13, others start later, others don't almost have any. It's about genetics, from my experiencie nothing to do with how much you developed on your mother's uterus, just genetics.",
"It might be like the growers/showers thing. If you have northerner genes you might be more likely to birth with hair. If you have southerner genes you might be more likely to be born bald.",
"I was born with ginger hair, my mothers half Asian and looks very Asian, my dad has the brown curly hair I have today. The doctors must have thought my mother is having an affair with a ginger...."
]
} | [] | [] | [
[],
[],
[
"http://en.wikipedia.org/wiki/Hair_follicle#Telogen_phase"
],
[],
[],
[],
[],
[],
[
"http://www.ncbi.nlm.nih.gov/pubmed/17150070"
],
[],
[],
[],
[]
] | ||
20hxbr | how automatic weapon can count to three when firing in 3-shot burst mode? | How automatic weapon know when to stop repeat firing when switched to 3-shot burst mode? Sample video:
_URL_0_ | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/20hxbr/eli5_how_automatic_weapon_can_count_to_three_when/ | {
"a_id": [
"cg3dzdd"
],
"score": [
2
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"text": [
"I'll assume you know how rifle's work in the first place. From what ive managed to see online Its basically a ratchet or cam system that determines how many shots are allowed in burst fire. I'ts quite complicated and I cant find much on it but there you go"
]
} | [] | [
"http://www.youtube.com/watch?v=f42qObMBbXM"
] | [
[]
] | |
67u22t | does a person with more injuries heal slower? | For example: a motorcyclist crashes and gets road rash over 10% of his body. Does he heal faster than if it were 20% of his body? Or does he heal at the same rate in both situations?
Edit: Assuming all other variables are constant. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/67u22t/eli5_does_a_person_with_more_injuries_heal_slower/ | {
"a_id": [
"dgt9cem",
"dgt9sw8"
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"score": [
3,
8
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"text": [
"Yes. If the input of nutrients into the body remains constant the person with more injuries needs more building blocks to repair the injured sites so it takes longer. Healing takes energy and the bodies metabolic rate is fairly constant. But the reality is far more complicated with different growth rates for different tissue variants in vascularity and a hundred other factors both internal and external.",
"Tricky question to answer. Here goes.\n\nLet's say the motorcyclist in the above example miraculously only got a \"bo-bo\" on his elbow; what happens? Cells near the scrape will signal that there's foreign bad stuff, and the Immune System needs to get its sorry ass over here pronto. Local Immune Cells called Dendritic Cells also act as \"sentinels\", and serve many purposes: vacuum up cellular debris, watch for foreign invaders, and both relay and amplify the alert to other Immune Cells that foreign bad stuff is present that needs to be expelled. Meanwhile, other cells will realize that they need to regrow, and will send signals to nearby blood vessels, which attract those blood vessels to grow out toward the scrape, providing nutrients for the cells to divide and replace those that are lost. All of this takes energy, and all of this takes nutrients, but it's seamlessly taken care of-you've [hopefully] got plenty of energy and nutrient reserves.\n\nSo what happens if it's a massive road rash, as in the entire surface area of a leg? (note: never, ever google road rash, what has been seen cannot be unseen). Well, the same thing happens, but multiplied over a large area...and there's a few complications. If the poor motorcyclist loses that much skin, he or she is much more susceptible to infection, and the reaction of the Immune System described in the previous paragraph can inadvertently go into overdrive, which is a bad thing. Those are other topics, but the point is all of this takes energy, and nutrients, so beyond feeling miserable, the [very miserable] motorcyclist will also feel drained. Assuming all the nutrients can get there--remember, the blood vessels will need to regrow as well to more efficiently provide nutrients--then all of the cells will work together at the same speed to repair the wound, but it won't be as fast as in Science Fiction. Some repairs go slower than others.\n\nSo, what happens if it's an even *worse* road rash, as in all of the back and chest? The body will heal at mostly the same rate [citation needed], because the same factors will be in play: cells detect injury has occurred, then send signals out that they need help repairing, and then begin the repair process, and *all* of the nearby cells will respond to this. But, there's a catch: what if the cells signal they need water, but the motorcyclist is dehydrated? Or, what if a nearby injury somehow prevents them from receiving nutrients or water, such as severe injury to blood vessels? Then, they'll keep trying, but they may be \"sidelined\" by more critical systems if the amount of available water (or other resource) gets critically low. Once enough water, nutrients, or energy are available, the repairs and regrowth will continue.\n\nTL;DR: As long as there is enough available water, nutrients, and energy, the body will repair itself at the same rate, but some factors can impact this rate, and not all repairs take place at the same speed."
]
} | [] | [] | [
[],
[]
] | |
43h6zy | when someone stands in the rain, how exactly is water inhaled? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/43h6zy/eli5_when_someone_stands_in_the_rain_how_exactly/ | {
"a_id": [
"czi5ya4"
],
"score": [
2
],
"text": [
"I think this might be a question for r/askdocs \n\nThe only problems I know of off hand is people with COPD can have issues in high humidity. High humidity increases the odds of exposure to mold and their spores. "
]
} | [] | [] | [
[]
] | ||
bank5o | why did people, historically, used to wear so many layers of clothes even in the summer? | Why did people wear all kinds of garments they don’t wear today along with their outer clothing, even in summer? Especially when they worked in the fields more than they do today; that seems uncomfortable. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bank5o/eli5_why_did_people_historically_used_to_wear_so/ | {
"a_id": [
"ekcv48r",
"ekcvzrt"
],
"score": [
6,
4
],
"text": [
"Protection. \n\nWhen you work outdoors in the summer, particularly when you are working in fields or brush you want to have long sleeved shirts of reasonably durable material to protect your arms from being scratched and to defend from sunburn. And yes people who work those kinds of jobs still wear that kind of clothing to this day. \n\nAdditionally the same principles of trapping pockets of air as insulation help to keep you cool in extreme heat just like it does to keep you warm in extreme cold. The exact clothing chosen will be different but you still want layers. Desert dwelling peoples still dress in layers to this day. The inner most layer absorbs your sweat and wicks it away from your body, taking body heat with it and cooling you down. It then holds that moisture in a place that is not directly exposed to outside air or the sun but still exposed to some air allowing it to evaporate at a slower rate cooling you further but in a more controlled manner than a single layer of clothing would allow. This is why you should always wear an undershirt if you are working outdoors in the heat and why athletes wear a product called underarmor. ",
"Here is an answer from an historical tailor for you. This in reference to my field 18th and 19th Century fashions. For the field hand, he would wear, shoes, hose, stockings, breeches\\[or long trousers\\] a shirt and a straw hat. Some workers would wear a knee length shirt OVER the above garments, to keep the under clothing clean-it is the ancestor of the welders apron, or the cooks apron. And that is it. Black slaves wore just some form of pants/breeches, in keeping with native customs of dress.\n\n The 'all kinds of garments' is for Sunday Best, or the wealthy; i.e. the attire we see on images of Benj. Franklin or Genl.Washington. And they are the same garments men of 2019 wear today for Sunday best, the style has changed a bit over time. The current style of '03 piece suit' dates from the late 19th and early 20th century. Indeed, I have worn a reproduction of an 1890 03 piece suit with a modern shirt, and no one could tell the difference{even tho there are a LOT of construction differences}. "
]
} | [] | [] | [
[],
[]
] | |
43dlr3 | after pulling you over, why do cops sometimes stand near your door handle, facing forward where you can't make eye contact, rather than standing at you mirror, facing you? | Sometimes an officer will stand closer to where your car door opens/where the handle is and face forward, making it impossible to make eye contact or even see their face.
What's the reason for this? Are the looking for something in particular? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/43dlr3/eli5_after_pulling_you_over_why_do_cops_sometimes/ | {
"a_id": [
"czhg9ex",
"czhi1dy",
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"score": [
17,
2,
3,
7
],
"text": [
" They want to be able to see your hands and glovebox, places you might have a weapon. You also can't easily exit the car if they stand by the handle. They don't need to see your face until they know they are safe.",
"It's to give them time to react in the event that you do something silly.",
"They are watching your hands, wheel, and glove box to make sure you do not go for a weapon or try to drive away. They are also positioned to prevent you from getting out if you try to run on foot. ",
"That section they're standing by is the B pillar, which is a metal post running from the floorpan to the roof, that supports the roof, provides the place to mount hinges to close the doors, and protects you in a crash. [This places the officer at an opportune position to view inside the front passenger compartment of the vehicle, as well as offering time to react if the driver were to pull a weapon.](_URL_1_) \n\nThe driver, unable to see the officer's body position behind the obstruction of the B pillar, cannot see the officer's weapon. Additionally, most drivers are right handed. [If a driver wanted to pull a weapon](_URL_2_), most likely using his right hand, to swing his arm over his body to the left would give the officer plenty of time to see the action, because his body position would inform the officer quite obviously.\n\nIt has been [documented](_URL_0_) that standing on the passenger side can increase the officer's safety even more: \n\n* 1) The driver may not expect you, and so you can view the situation in the car before they notice you approaching. \n\n* 2) Headrests and passenger seats obstruct the officer even more from the line of fire. \n\n* 3) Officers standing at the B pillar on the opposite side, if opened fire upon, have been demonstrated to reach a safe zone faster than officers standing next to the driver."
]
} | [] | [] | [
[],
[],
[],
[
"https://www.policeone.com/Officer-Safety/articles/6136658-Force-Science-study-pinpoints-vehicle-stop-vulnerabilities/",
"http://www.forcescience.org/trafficstop.html",
"http://www.realpolice.net/forums/archive/t-108865.html"
]
] |
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