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9tdbcs | "Bloody" Mary Tudor has the bad reputation of being brutal to her Protestant subjects. But when Elizabeth I ascended to the thrown, she was similarly brutal to her Catholic subjects. Was Mary more brutal, or does she just get the moniker "Bloody" because the country is more Protestant today? | That is to say, does Mary get a bad rep because the country never went back to being Catholic and the winners write history? Or was she really a lot worse with respect to persecuting the other side? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/9tdbcs/bloody_mary_tudor_has_the_bad_reputation_of_being/ | {
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"On one hand, Mary was actually a lenient, merciful person. She was ready to pardon Lady Jane Grey, until the Wyatt Rebellion forced her to change her mind: something that her far-bloodier father Henry VIII would not have hesitated over for a moment. Though she was certainly devout, her tally of 280 or so burnt heretics perhaps was not that great by 16th c. standards. But, on the other hand, it was substantial, considering it was done over only three years, from 1555 to her death in 1558. And it differed from previous English persecutions: they didn't kill as many people. When Archbishop William Warham went after 46 Lollards in 1511, for example, only 5 were burnt. It was typically the leaders who got the bonfire . Like Thomas Man, a wandering preacher who was burned in Smithfield in 1518. Mary went after even the lowliest, like the Colchester Martyrs, and went for them root and branch, not only burning modest tradesmen but their wives as well. That made her an easy target in John Foxe's *Book of Martyrs.*\n\nShe was also an unsuccessful monarch, lasting only five years, leaving no heir, and losing Calais, so it was easy to cast her as a villain. And, in the tradition of winners writing the histories, of course the end of Mary I and Catholic rule was seen as a victory for the Anglican Church. Eamon Duffy challenged that in his book, [The Stripping of the Altars](_URL_0_), ( and expanded it in his later Fires of Faith ) reasonably asking the question, why was it such a bad thing for England to have become Catholic again? And wouldn't it have been just fine, staying that way?\n\nComparing her to Elizabeth, however, is difficult. Elizabeth had a much larger political problem with the Catholic church than Mary had with her heretics: the Pope did not regard her as legitimate ( because Henry could not legally have divorced Catherine of Aragon) and said so: so she was under real threat. Her cousin Mary ( of Scots) was far preferable to Catholics and the center of plots, which is why Mary eventually had to be executed. It is quite hard to separate politics, economics and religion at this time: Mary I saw heresy as a terrible danger to her subjects' salvation. Spain's Philip II saw his elimination of heresy to be practical foreign policy, a mission handed to him by his father Charles V. But Elizabeth could be simply worried about the simple loyalty of her Catholic subjects, regardless of doctrine. The Jesuits coming into the country were trying to unseat her, and asking for assistance from the Catholic English, which they sometimes got: there was , for example, the Ridolfi Plot involving the Ear of Arundel and family. Elizabeth did not, however, go after the Catholics root and branch- plenty managed to keep a low-enough profile to survive. And she also had a very, very, long reign compared to Mary's, so you can't really just compare numbers: if she had kept Mary's pace, after 45 years she would have burned 2,240 people.\n\n & #x200B;\n\n & #x200B;"
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cvp4sh | how do sites like dhgate easily get away with selling fake products online? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cvp4sh/eli5_how_do_sites_like_dhgate_easily_get_away/ | {
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"I think just about everything there is shipped straight from China. And a lot of the stuff isn't necessarily \"fake\" but is just very low quality or an obvious knockoff that is not being made to look like the real product.",
"Fake products are a big problem for a lot of sites that let sellers sell directly to buyers. Amazon, eBay, Etsy, \n\nPart of the problem is that it’s very easy to set up a selling account. Sellers can list items very quickly, with little to no verification from the selling platform. It’s only when buyers complain, or the owner of the copyright/trademark files a case, that anything is done. Even if the platform takes down the seller. It’s pretty easy for them to set up a new account under a different name/email address. \n\nPart of the problem is also that current law doesn’t hold the platform owner (amazon, eBay, etc) in any way responsible for damages. If someone is caught selling fake NFL merchandise, the NFL can’t go after Amazon for damages. So there’s little incentive for the platform owners to police their sites."
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13s0eo | How long do landmines remain active? | How long does it take for the explosives to become inert? Does the process by which the mines become unable to explode speed or slow depending on climate and soil composition? | askscience | http://www.reddit.com/r/askscience/comments/13s0eo/how_long_do_landmines_remain_active/ | {
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"Every now and then here in Virginia they find ordinance from the Civil War that is still dangerous, although landmines weren't really invented yet.",
"According to the wikipedia article for [Anti-personnel mines](_URL_1_) the most common primer/detonator charge used is an explosive called [RDX](_URL_0_) which seems to be able to maintain its capacity to explode for a very long time (extremely stable). \n\nCommonly used things for main charge seem to be TNT, Composition B, and a form of treated RDX. The US used Tetryl as its main charge. I can't find anything about how long they last, but it seems that they all pose some sort of toxicity to soil and climate depending on the environment they're in. If they're in a landmine though, it's probably sealed, so there isn't any leakage. \n\nSo you'd probably have to wait for the fuze/detonator to stop functioning. Most mines use Lead Azide in this, but when protected from humidity, it's completely stable, so it wouldn't set off secondary explosives. \n\nSo you'd have to wait for the spring in the detonator to degrade. Yeah....\n\nLandmines stay around a loooooong time. There's a reason they were made illegal. You know, besides the immediate civilian casualties. ",
"Depends on when and who manufactured it. Many of them now have features where they will self destruct after a preset time. Many are now made of plastic and are extremely difficult to detect - even by those who laid them. Not much point in denying the enemy use of territory if you can't use it yourself. Older mines are often active for decades after being laid. The explosive is very stable, the detonation mechanism not so much."
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32cnaa | [Meta] Why are there always so many questions about WWII? | Seriously, there's more to history than just WWII and directly related events. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/32cnaa/meta_why_are_there_always_so_many_questions_about/ | {
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"It all goes back to popular culture. Questions about WWI & WWII, the Middle Ages, and Rome and Greece pop up constantly, and it's not hard to figure out why. How many movies/shows/games have been made about WWII in the last 15 years? How many about Rome? I'm convinced that Game of Thrones alone accounts for much of our medieval interest, and it's not even set on *Earth* or in the *Middle Ages*; if anything, it's a weird quasi-War of the Roses setting, and thus early modern.",
"You might enjoy some earlier posts on the topic\n\n* [[META] Can We, AskHistorians take a month off of all things WWII and Nazi related?](_URL_1_)\n\n* [[META] Moratorium on Hitler hypotheticals?](_URL_2_)\n\n* [Why do we love WW2?](_URL_0_)\n\nAlso, a **Public Service Announcement**: if there are subjects that you don't want to see, download the free *Reddit Enhancement Suite (RES)* browser add-on: it will allow you to automatically filter out posts containing specific keywords. In the *RES settings console*, click the *Filters* tab, scroll down to the *keywords* section and define the keywords you don't want to see in this sub, e.g. WW2, WWII, Hitler, Nazi, Stalin, Holocaust, Hiroshima... ",
"I feel the answer is because its mythologized image has clear \"good\" and \"bad\" side unlike most of other cases where both sides can be accused of being somewhat \"evil\" (modern Americans probably don't think Vietnam was necessary and just war, just as Russians may be resentful about Afghanistan, but both remember WW2 as heroic great war). There are also many controversies there so it's a big playing field for second-opinion bias like \"the real evil were Allies/USSR\", genocide Olympics, \"all the work was done by USA/USSR\", \"Hiroshima is as bad as Holocaust\" etc.",
"World War Two is often (very wrongly) seen as a clear-cut good vs evil confrontation, it also in many ways was both the first and last war of its kind and it shaped the contemporary world more than any other major event by ushering in digital computing and nuclear fission. Additionally the sheer scope of the conflict and the fact that it took place very recently makes WW2 the most appealing historical subject for the general population, judging by the constant release of WW2 books, movies and video games every year, it's clear to me that the second world war will continue to generate massive amounts of attention in decades to come."
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j3uw7 | whats the difference between "union" rugby, and "league" rugby? eli5 | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/j3uw7/whats_the_difference_between_union_rugby_and/ | {
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"League has 13 players per side, and play stops as soon as a player is tackled, with the team in possession keeping the ball and the defending team having to go back ten metres and defend again. Once the defending team successfully completes 6 tackles, they are awarded possession.\n\nUnion has 15 players per side (2 extra forwards - the flankers), and play keeps going until either somebody scores, the ball goes out of play or the referee blows his whistle for an infringement of some kind. When somebody is tackled, rather than stopping, everybody steams in and fights for possession of the ball.\n\nThere are other differences, but that's really the big divide.",
"Rugby Union and Rugby League are versions of the same game.\n\nGenerally speaking, the object is the same. To earn points, the ball must be carried over the try line and touched down (this scores a \"try\") or the ball can be drop-kicked over the goal posts. After a try is scored, the ball can be place-kicked or drop-kicked from in-line with the position of the try to \"convert\" the try and earn two extra points. Whichever team has more points after eighty minutes of play wins the game.\n\nThe organizing groups for the sports split about a hundred years ago, because some people wanted to be paid by their team when they took time off work to play. Others thought being paid to play would ruin the game. The people who wanted to be paid split off and formed the \"Rugby League\", those who didn't were the \"Rugby Union\".\n\nThere wasn't any intent to create a separate type of rugby when the split happened, but after hundred years of having different leaders the rules have become different under the two groups of leaders.\n\nIn Rugby League:\n\n- There are two fewer players in each team (13 per team, with two fewer \"forwards\" than rugby union)\n- Tries are worth four points\n- Drop kicks are worth one point\n- Penalty kicks are worth two points\n- Most of the parts of the game that cause the Union version to stop or slow down have been \"sped up\". For example Scrums are pretty much uncontested and Lines outs have been removed from the game. \n- The above causes the most obvious difference in the way play unfolds. When a player is tackled with the ball, his team keeps possession. The tackled player stands, and rolls the ball back under his foot to a team mate.\n- If there is doubt over whether a try is scored, the benefit of the doubt goes to the attacking team\n\nIn Rugby Union:\n\n- There are fifteen players in each team\n- Tries are worth five points\n- Drop kicks are worth three points\n- Penalty kicks are worth three points\n- In contrast to Rugby League, when a player is tackled, members of both team will try to get the ball from him. This forms a \"ruck\" over the ball as both teams try to work the ball back to \"their\" side of the ruck. People who don't understand what's happening can find this very boring since you can't see what is going on.\n- Every restart is contested; scrums, line-outs and rucks are intended to allow the defending side to have a chance to get possession of the ball. This added competition tends, though, to lead to more penalties being awarded, which can slow down the game.\n\n- If there is doubt over whether a try is scored, the benefit of the doubt goes to the defenders\n"
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7mjoo2 | when a train enters a tunnel, what is the cause of the sudden pressure drop in the cabin? | I was riding CalTrain today and in the 4 tunnels before the final stop there was a quite noticable pressure change (which I found to be a drop in pressure using the barometer on my phone). Thank you!
Rule 7: In accordance with rule 7, I did search this question up beforehand, and there were two posts about the topic, but one of the posts described an increase in pressure (which I found not to be the case) and the other didn't have that great of an explanation. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7mjoo2/eli5_when_a_train_enters_a_tunnel_what_is_the/ | {
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"When air speeds up its pressure drops. As the train passes through the tunnel the air around the sides is being squeezed into a much tighter space than before the train’s presence. A narrowing of the space between the train and the tunnel causes the air to speed up which also means the pressure of the air drops as it speeds up; speed being relative in that it’s the train that’s moving while the air is still but the effect is the same. "
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3hrjqw | Would soil on Mars grow plants? | In the movie The Martian the main character seems to grows plants from martian dirt. Could martian dirt grow plants or would it need organics mixed into the dirt to make it grow plants? | askscience | http://www.reddit.com/r/askscience/comments/3hrjqw/would_soil_on_mars_grow_plants/ | {
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"Nope! Not as it is naturally. In the book (which is fantastic, by the way), Mark Watney actually adds fertilizer (poop) and water to the soil, so it's not as simple as it seems in the trailer. \n\nThat said, plants still wouldn't grow in Martian soil in reality. I'm no botanist, but one major problem with the soil on Mars is that it's covered in perchlorate, an extremely reactive (ie explosive) oxidizer, which is toxic. I'm sure there are other problems as well... ",
"The three main problems are 1)a lack of nitrogen compounds, 2)the presence of toxic perchlorate salts, and 3)it's very high (for soil) pH and total alkalinity. \n\nSetting up facilities to separate and process nitrogen from the atmosphere into other compounds, would be one of the first priorities for anyone who intended to live on mars long term.\n\n"
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ct9pwk | what causes the ear-piercing sensation caused by grinding forks against plates or nails on a chalkboard? or even the thought of it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ct9pwk/eli5_what_causes_the_earpiercing_sensation_caused/ | {
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"It is similar to shrieks made by mammals in times of distress or danger and is an evolutionary artifact. It's supposed to be 'jarring' so it gets your attention.",
"I heard somewhere that it was because it was close to the sound one of our predator made when we were primates. That, or it is really close to the death scream of a primate, which both indicate impending danger.\n\nHowever, I could be wrong. I'm not really sure.",
"Nobody really knows why people get \"the chills\" but the best theory I've heard is that your teeth don't have nerves going all the way to the end so any sound that makes your brain think you're in danger of losing enamel triggers a response to protect your teeth.",
"Wait, people are bothered by the sound of forks on plates? How do they eat?",
"I cringe HARD when people eating with forks stick the fork in their mouth, bite down, and slide the fork out through their teeth. \n\nThese people need straightjackets.",
"Honestly I’ve scratched a chalkboard and it really wasn’t that bad. \n\nAlthough at my work, I was cutting food for a resident (nursing home), scraped the fork against a plate on accident, and felt so god damn uncomfortable.",
"Help, I need to know that there is at least one more person out there who gets that same feeling from wet sand. I could never stand it. The very thought of someone walking in wet sand or - help me God - digs around in it with their bare hands gives me the shivers and goosebumps all over.",
"In our country, our word for that is \"ngilo\" or \"pangingilo\", to refer to the sound, as well as to mean tooth ache",
"I get a very similar sensation when I rub some types of synthetic materials together or with other objects, my family doesn't get it.",
"And how common is it?\nCuz those have never bothered me",
"Kinda a tangent, but autistic people and anyone who has auditory sensitivity issues can be really well understood as people who have a \"nails on a chalkboard\" reaction to a wider variety of sounds than most people. I've thought of this comparison as usually a good way to explain auditory sensitivities to most people.",
"Your ears are *super* sensitive to the 2K-5KHz region of the sound spectrum, and nails on chalkboard is right in that range.",
"I didn't notice anyone mention this but I absolutely hate the sound of chewing. Even with their mouth closed. Not all people but some still make that sqwashing sound, and it triggers a huge amount anxiety/anger in my brain. Mouth open chewing is far worse. I find it hard to eat around other people in quiet rooms. My angel gf will wait for us both to start eating, and I'll always turn on the TV for background noise. I've tried endlessly to not let it bother me but never succeeded. 30 years old and it still drives me bonkers. I don't often tell the loud chewers because its rude but damn do I hate it/them indirectly. Sometimes it will boil up until I tell them to please stop. \nThis also converts into other noises like sniffling and typing, or pretty much anything repetative. \nI truly hate it about myself. Thankfully a vast majority of the time I bear through it silently.",
"I wonder if it's like a negative version of ASMR. Everything fits exactly, it's just the experience is negative rather than soothing.",
"Is it bad that these sounds don't bother me?",
"I'm not gonna read the comments on this thread.\n\n*proceeds to read all the comments and gets the uneasy sensation every time someone mentions nails and chalkboard*",
"From what I understand, it all just comes down to dissonance. The brain is weirdly phenomenal at patterns; and vibrations within the ear are part of it. The sounds are causing wavelengths that are disorienting because they don’t match each other in a harmonic way.\n\nInterestingly, those wavelengths are part of why we find music so good! They match!",
"Or scraping aluminum foil with a metal object?",
"I mean the animalistic theories are nice. But I'm pretty sure it's just because it's an incredibly high pitched sound. High frequencies really hurt our ears, and it's incredibly loud to boot. Also it could a case it has some kind of resonate frequency. Either way that sound is stuck in my ears now and I want to die."
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eqbw3s | Books on the Anarchy in England? | I am vastly interested in the subject, yet there is no mention of it in the book list, and I can't seem to find many books on it otherwise, much less their reliability and general readability. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/eqbw3s/books_on_the_anarchy_in_england/ | {
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"If your 'the Anarchy in England' means the famous (notorious) civil war period in the 12th century, I can mainly recommend the following ones: \n\n* [Crouch, David. *The Reign of King Stephen: 1135-1154.* Harlow: Longman, 2000.](_URL_3_) \n* [Dalton, Paul & Graeme J. White (eds.). *King Stephen's Reign, 1135-1154*. Woodbridge: Boydell, 2008.](_URL_2_) \n* King, Edmund (ed.). *The Anarchy of King Stephen's Reign*. Oxford: Clarendon, 1994. \n* [_______. *King Stephen (The English Monarchs Series)*. New Haven: Yale UP, 2010; pbk 2012.](_URL_1_) \n\nThe historiographical topic of 'Anarchy' period almost inevitably intertwined with how we evaluate the various aspect of politics under the reign of King Stephen (1135-53). In short, the good book of 'the Anarchy' is the good book on him at the same time, and you have plenty of them. Among others, two collection of essays, respectively edited by Dalton & White and by King represent the development of the revisionist interpretation of Stephen's reign that had originally been initiated by Edmund King in the 1970s. King has been without doubt the leading scholar in this field of research, but if you find his writing style too heavy for your taste, I'd rather instead recommend Crouch's book as the first to read. \n\nIf you are not really confident on the essential knowledge of this topic, Carl Watkins' [recent small booklet](_URL_0_) of Penguin Monarchs might also serve as an introductory work, though I assume that you have had enough knowledge of this period by reading some historical novels and TV series like Ken Follett's *Pillar of the Earth* or Ellis Peters' *Brother Cadfael* series."
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1fbppw | How did our universe become so organized? | this question pertains to entropy in the early universe. as i understand it, entropy is the habit of particles to move from organized to disorganized. from order to chaos. we know that entropy always increases, and can never be reversed.
knowing this, when our universe was young how did any form of organized structure form in the face of entropy? wouldn't entropy have kept everything random and chaotic? how did the first atoms form, then the stars that forged them into the elements with this force of chaos trying to drive them apart? | askscience | http://www.reddit.com/r/askscience/comments/1fbppw/how_did_our_universe_become_so_organized/ | {
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"A \"random and chaotic\" gas is only a maximal entropy state in the absence of gravity. If you include gravity, then you'd have to include that in the measure of entropy. I saw a talk by Roger Penrose in which he suggested that black holes are the maximal entropy state of a given volume of space and thus tell us the eventual endpoint of the universe. There are [additional issues](_URL_0_) to do with the universe also expanding, and so the maximum possible entropy increasing.\n\nSo, probably once you account for gravity, the \"organisation\" that you see is in fact higher entropy than the more uniform state it was in before.",
"The error in your question is that you're taking entropy to mean \"disorder\" which is not entirely correct. If that's all it was, then you'd say \"of course a planet, a solid spherical object, has more order than a big cloud of gas, so it must have less entropy\". But entropy is better described as an inverse measure of how far something is from energy equilibrium, or how much work a system can do.\n\nWith most terrestrial systems, disorder/order works well, but on a large scale where gravity comes into play, that defintition breaks down. We talk of objects/systems that have potential energy as ones that are high up in a gravitational field and can fall, thereby performing work. Core principle of hydroelectric dams. Therefore, a giant spread-out cloud of gas has a lot of potential energy - it will eventually collapse under gravity and form a star/planet, radiating heat out as it does so. A planet is in a much lower 'energy-state' than the gas, and so has a much higher entropy.",
"The universe today actually has much higher entropy than it did when it \"began\" in the big bang. As others have mentioned, in the presence of gravity, the usual intuitions about what represents order vs. disorder break down. A star by itself may appear more ordered than the same amount of matter scattered randomly around, but the process of stellar evolution actually ends up increasing disorder by taking coherent gravitational energy and converting it into disordered energy (heat, light released etc).\n\nSo it's not that stars and planets formed in spite of thermodynamics. On the contrary, thermodynamics has driven cosmological evolution since the big bang.\n\nThat said, the universe we see is definitely a lot more organized than it could be.\n\nYour question then becomes, how was our universe so organized to begin with? All the structure we see now seems quite organized, and yet it must have come from something even more organized. No one knows the answer to this question, though there is speculation.\n\nWhen you start looking at things through this lens, all sort of logical problems pop up. See _URL_0_\n\nSo the question is difficult to answer in a scientific way at present."
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82o71w | is athleticism genetic? if so how? | I'm trying to get back into sports since I've started uni and feel this is the best opportunity to after 3-4 years but I feel I've got nothing going for me atm athletically other than my stamina, I've got an average vertical and average strength I come from a pretty athletic family is it because I've not done any sport for the past 4 years or have I just lucked out in genetics? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/82o71w/eli5_is_athleticism_genetic_if_so_how/ | {
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"It is to a degree; when it comes to how well your body heals itself, how efficiently your blood carries oxygen, the maintenance of bone tissue, your body type, things like that. \n\nYour body can change some stuff like muscle mass, and it's all in the brain when it comes to how you maneuver your body. So it's a combination of nature and nurture.",
"There is some genetic component but unless it's a disability effort makes far more of a difference.",
"It plays a factor to a degree, and what degree that is is up for debate. The poor grammar in your question makes it difficult to determing exactly what your problem is. If you are wondering why you are not very good at sports after not doing sports for several years, then you answered your own question. Peek athletic performance requires constant long term training. If you are wondering why you are still somewhat athletic despite not doing much, it is because it takes a while to go away completely especially if you don't lead a partcularly sedentary lifestyle or overeat."
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1y77vj | So if Halley's Comet was supposedly created during/shortly after the formation of our solar system, how has it survived this long? | The beginning of our solar system was a spinning nightmare with collisions lighting up the night sky on a budding protoplanet, so I was just observing that Halley's Comet seems to be a significantly unlikely reoccurrence in our solar system that's gone through such a destructive and constructive history. | askscience | http://www.reddit.com/r/askscience/comments/1y77vj/so_if_halleys_comet_was_supposedly_created/ | {
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"So you're right, Halley's Comet has almost certainly *not* been swinging through the inner solar system every 76 years since the beginning of our solar system.\n\nThe important thing, though, is that while Halley's Comet probably was created with the rest of the solar system, it has not been on its current orbit for the past 4.6 billion years. That's far too much time - even if it hadn't been hit or forcibly perturbed out of the solar system, the comet certainly would have evaporated by now.\n\nOur best guess is that, at best, Halley's comet has been in its current orbit for only a [few hundred-thousand years](_URL_0_). Given that the furthest point of its orbit is right in the Kuiper Belt, it seems likely that's where it began life, and remained in a distant circular orbit until very recently (although [some argue](_URL_0_) it originated in the much further Oort Cloud). Most likely it was perturbed from this orbit some hundred-thousand years ago by a near-pass of another Kuiper Belt Object, or possibly an orbital resonance with Neptune."
]
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"http://articles.adsabs.harvard.edu/full/1990A%26A...227..264D"
]
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|
1q2wyj | why do people call australia a prison? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1q2wyj/eli5_why_do_people_call_australia_a_prison/ | {
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"It was used as a prison for the English empire ",
"Most of the first settlers were exiles from Britain, usually criminals.",
"When the British found it, they decided it was a great place to put their criminals. ",
"The British--they live on a crowded, cold, wet, little island with dubious neighbours. The discover a magnificent land, with sunshine, beaches, wide open spaces unique flora and fauna, and send their criminals there!",
"Australia was first colonised by the British as prison. They sent convicts from over crowded prisons in England to Sydney and used convict labour to build the colony. Convicts were the majority of colonists for the first approx. 30 years of British colonisation (1788-1820s).\n\nCriminals in Britain and Ireland were often sentenced to 7 years hard labour in New South Wales. Once they had served their sentence (or earlier if they behaved well) they were given a ticket of freedom and allowed to set up their own small farms.\n\nWikipedia's article on Australian History is fairly comprehensive: _URL_0_\n "
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||
2zqo1q | If the speed of light is constant, how does Red Shift happen? | The speed of light is always constant, regardless of the position and relative speed of the observer. In that case how come light is subject to the Doppler effect and gives us Red Shift? | askscience | http://www.reddit.com/r/askscience/comments/2zqo1q/if_the_speed_of_light_is_constant_how_does_red/ | {
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"The red shift is a shift in wavelength, not a shift in speed. Speed and wavelength are entirely different properties. They are related according to the equation:\n\nfrequency = speed/wavelength\n\nSince the speed is constant in all frames, an increase in the wavelength (a redshift) must be accompanied by a decrease in the frequency.\n\nThe Doppler shift makes the most sense if you think of light as a wave. When a source is traveling away from you, each wave peak emitted at subsequently later moments in time is emitted at farther and farther away points in space. Therefore, the wave peaks that reach you must be farther apart, i.e. the wavelength has increased. But each individual wave peak still travels towards you at the same speed. People often think the Doppler shift should change the speed because they are picturing photons as literal little balls being shot out of a moving cannon, which is a false picture."
]
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[]
] |
|
ruf91 | How effective is chewing gum compared with brushing only, or brushing and flossing? | Is it more effective at cleaning between teeth than brushing without flossing?
Plenty of gum marketing online but can't seem to find any hard data on it's effectiveness, do they even know? | askscience | http://www.reddit.com/r/askscience/comments/ruf91/how_effective_is_chewing_gum_compared_with/ | {
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"I'd suggest finding 10 dentists and asking 7 of them. :)\n\n-----\n\nSeriously though pretty useless. Brushing moves foodstuff away from the gums on the surface of the teeth and floss from in-between the teeth. The only advantage of gum is increasing saliva flow, though some contain antibacterial agents or aid in re-mineralization.\n\nIn the future if you are looking for some scientific info beyond propaganda (i.e. journals, papers, articles) try [google scholar](_URL_0_)."
]
} | [] | [] | [
[
"http://scholar.google.com"
]
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|
mc232 | how does chest decongestant work along side cough suppressant? | I may be completely wrong about this but from what I've understood chest decongestant breaks down mucus and other bad stuff in your lungs and makes you cough it all out. And cough suppressant just makes you stop coughing. Now my question is most cold medicines have both of these in them. How do they work together? Don't they counteract each other? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/mc232/eli5_how_does_chest_decongestant_work_along_side/ | {
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"so stuff like Mucinex includes two chemicals normally, Dextromethorphan and Guaifenesin. You have correctly identified the paradox of cough medicine, the Dextro acts as a cough suppressant by depressed activity in the part of your brain that tells you to initiate the cough reflex. The Guaifenesin acts as an expectorant, that is it causes the mucus to swell with water making it easier and heavier to cough out, normally the mucus isnt super thick but kinda wispy and thin so the air travels right past it. What is happening is that the dextro eases your reflex to cough, which can become painful, so that the Guaifensein has a chance to make it get all thick and gooey. Now the dextro suppresses but doesnt prevent, that is it makes it so more neurons in your brain need to fire before it tells your lungs to cough. Which means as it gets ticker and heavier your lungs keep going 'help help we need to get this out of here!' so you cough eventually. The logic here is that it reduces the number of coughs you have and makes them more productive.\n\nHope that helps (most of my sources is wiki and erowid :-/)",
"My doctor recommended against taking them together. She said take guaifenesin during the day, and take dextromethorphan at night ONLY if you have an uncontrollable cough that's keeping you from sleeping. If you have a lot of mucus, you shouldn't take a cough suppressant. This jives with my experience. I never take cough suppressants for upper respiratory infections; they make me feel like I'm going to suffocate. ",
"so stuff like Mucinex includes two chemicals normally, Dextromethorphan and Guaifenesin. You have correctly identified the paradox of cough medicine, the Dextro acts as a cough suppressant by depressed activity in the part of your brain that tells you to initiate the cough reflex. The Guaifenesin acts as an expectorant, that is it causes the mucus to swell with water making it easier and heavier to cough out, normally the mucus isnt super thick but kinda wispy and thin so the air travels right past it. What is happening is that the dextro eases your reflex to cough, which can become painful, so that the Guaifensein has a chance to make it get all thick and gooey. Now the dextro suppresses but doesnt prevent, that is it makes it so more neurons in your brain need to fire before it tells your lungs to cough. Which means as it gets ticker and heavier your lungs keep going 'help help we need to get this out of here!' so you cough eventually. The logic here is that it reduces the number of coughs you have and makes them more productive.\n\nHope that helps (most of my sources is wiki and erowid :-/)",
"My doctor recommended against taking them together. She said take guaifenesin during the day, and take dextromethorphan at night ONLY if you have an uncontrollable cough that's keeping you from sleeping. If you have a lot of mucus, you shouldn't take a cough suppressant. This jives with my experience. I never take cough suppressants for upper respiratory infections; they make me feel like I'm going to suffocate. "
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yqm12 | dada art | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/yqm12/eli5_dada_art/ | {
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"Basically art that has no meaning or is supposed to be superficial and just aesthetically pleasing. If you were to ask the artist what the painting means he/she would say \"who cares\".",
"With art, there are always those nagging questions that never get entirely satisfactory answers one way or the other. Questions like \"does art need to be aesthetically pleasing?\", and \"does art need to have a deeper meaning?\"; \"Is everything we put in a museum art, and what happens when you remove it from said museum?\"\n\nDada attempted to throw out all the old rules and ideas, and see what happened. That meant there was poetry that did not conform to the rule that poetry needs to contain actual words. Art that was not actually art at all, except somebody put it in a museum. Nonsense art, or possibly anti-art.\n\nThis generates some questions for the modern audience. Questions like \"why the hell would I pay to go look at an empty frame?\" and \"exactly what kind of nonsense is this?\"\n\nIn defence of Dada, it's power is exactly that it makes us ask those kind of questions. It inspired new generations of artists to make up new rules and ideas for their art, giving birth to all kinds of artistic movements occasionally lumped together as \"post-modern art\". It forces the audience to contemplation about what exactly they were expecting when they entered a museum.\n\nNot everybody will appreciate it. There's a group of people who are not necessarily looking to have their assumptions challenged, either because they went through it, have asked themselves the questions, rendering Dada more than a little pointless and a touch boring, or because they just want to look at pretty pictures of landscapes and famous generals on horses (or stated in a more high-brow fashion: they're looking for beauty and meaning, rather than introspection).\n\nPersonally, I consider all three approaches to Dada entirely valid. Nobody *has* to appreciate Dada; I generally don't. What I do object to, though, is the \"degenerate art\" approach, where people essentially say that because they don't get it or appreciate it, it should not be made or actively destroyed."
]
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[],
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1rk4v2 | if video game companies lose so much money on consoles, and make so much money on games, why don't they collaborate on one console that can play any game? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1rk4v2/eli5_if_video_game_companies_lose_so_much_money/ | {
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"Like a PC?",
"And share the profits? Why don't all the grocery stores combine since they sell the same things?",
"Because they can make *more* money if they convince developers to make exclusives or they create their own IP to give them an edge. Look at Nintendo for example, if it weren't for Mario, Zelda, and a few others the Wii would have died a long time ago for lack of power. ",
"Rarely happens: They are building a brand image- which is worth more than money they can really lose. Building a brand is their main focus than just profit margins sometimes.\n\nGames: they get a subsidy but most money really goes to the developers who spend that time to create a game for your console. In few cases, some game-makers even become exclusive for the console (ie Halo-Microsoft, God of War/Sony, Mario! for Nintendo)\n\nSO in a way, they are already collaborating and in few years time, they turn profit on consoles anyways as life-span of these consoles tend to be anywhere from 5-7 years and production costs go down!"
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2a6r2b | how is 1984 a foreshadowing of the modern western world? | I've read the book and seen the film, and while there are certainly some similarities between the things portrayed in the novel and our world, most notably surveillance, I'm not really sure how people can feel confident saying that the world we live in today is the world that is portrayed in the novel. 1984 seems to omit two of the key driving forces behind Western society - capitalism and consumerism. The people I hear making the comparison often tend to be left-wing (which is how I would describe my own personal politics, for the record), but if anything the novel appears to be portraying a socialist dystopia, and seems closer to North Korea or China than it does to the UK or USA.
Don't get me wrong, there are things massively wrong with our society, but I feel like despite everything, the fact we are able to compare our society to 1984 kinda dampens the comparison itself. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2a6r2b/eli5_how_is_1984_a_foreshadowing_of_the_modern/ | {
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"This behavior is an example of political hyperbole. It is, in my opinion, the equivalent of saying that President Obama is a communist for supporting higher minimum wages or single payer health insurance. \n\nNeither hyperbole is accurate, but within political circles, both are widely understood analogies.",
"Perhaps if you don't take it is a literal foreshadowing it might help. Aspects of the book do ring true to modern times. \n\n For instance, the idea of censorship and privacy. In some respects, we really do lack privacy in modern Western society. We are constantly being followed online. Our Clicks, this message, posts, Likes are all being tracked. In this sense Big Brother is watching what we are doing on a daily basis online. Also, texts and phone calls have been noted to be monitored as well. \n\nI haven't read the book in a couple years so I can't remember all the details. ",
"I remember on his old HBO show, Dennis Miller had a rant about how he thinks people act like the government is after them because it makes them feel important enough for a big organization to go after. He ended it with \"No one's out to get you. No one gives a shit whether you live or die. There! You feel better now?\"",
"Not an explanation, but I think that Brave New World (where mindless consumerism and petty distractions are letting the public be duped) is a more accurate metaphor",
"people have been making the comparison to dystopian novels since forever. these works are *designed* to be just close enough to reality to get you on edge."
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xswri | What are the most promising ideas for faster than light travel? | askscience | http://www.reddit.com/r/askscience/comments/xswri/what_are_the_most_promising_ideas_for_faster_than/ | {
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" > What are the most promising ideas for faster than light travel?\n\nThere are none. Everything we know or suspect about the universe tells us that it is not possible, even in principle, to travel faster than the speed of light.\n\n > the Alcubierre drive\n\nThe Alcubierre drive, like wormholes, is something that pops up when you run the equations of relativity the wrong way around. You start with what you want spacetime to look like, and then figure out what sort of energy distribution is required to get that spacetime. When you do this, you tend to find that you need unphysical configurations—i.e., the energy distribution violates certain conditions that we expect to be true. While they might, in principle, *not* be true, the degree to which they must be violated to create such a drive doesn't seem likely given that we've never *seen* any such violation. The alternative versions that don't require this sort of \"exotic matter\" rely on completely speculative physical models that have never been demonstrated to correspond to reality and, in any case, still require so much energy that if you kept your fuel source on board the ship then the whole thing would collapse into a black hole before you could ever turn it on."
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||
uguse | What is the biggest atom that our Sun can produce? | Also, what is the biggest atom that the biggest star we are aware of can produce?
How big would a star have to be to produce an atom like Ununoctium?
Thanks guys really helped! | askscience | http://www.reddit.com/r/askscience/comments/uguse/what_is_the_biggest_atom_that_our_sun_can_produce/ | {
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"Fusion of elements within stars stop with Iron. As mynameiswillem points out, elements higher than Iron require a catalyst, like a supernova, to develop. As for the largest natural occurring element, Californium. The remaining elements are far too unstable to remain naturally.",
"[This](_URL_0_) is kind of long but essentially our sun will only be able to produce carbon.\nFusion after iron does happen. That is how we get everything heavier that iron. It just requires more energy than it puts out. Usually in the form of the gravitational collapse of a supernova. "
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[],
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"http://www.astronomycast.com/2008/09/ep-107-nucleosynthesis-elements-from-stars/"
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2nginv | Why is education on human atrocities during WW2 always focused on the holocaust, and not other ones like the ones committed by Italy in Africa or Japan in China/Asia, and beyond that the famine and suffering in the British Empire? | I understand the rest are discussed and documented as well, but why is the focus on the Holocaust so *disproportionally* focused on compared to other human atrocities? What makes industrial capacity for murder any different or crueler than chopping off someone's head for a game or shoving an iron rod or fire rockets up a woman's vagina? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2nginv/why_is_education_on_human_atrocities_during_ww2/ | {
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"As a follow up question, or rather clarification: In what way do you feel that the education is in fact focused on things like the holocaust rather than those committed in Africa or Asia? I assume by your question you grew up in a country in which this was the case. However for people growing up in Nanjing, the Japanese atrocities are more represented than Nazi Germany's.\n\nSo are you just speaking in terms of Western education? Or do you have the impression that it is globally so unbalanced?",
"I would challenge your assertion that education is \"always\" focused on the holocaust, and not the other ones. At the very least it depends on where the education is actually taking place. As /u/keyilan points out, students in China probably learn more about Japanese atrocities there than German atrocities in Europe. If you are from a country with stronger European ties (or even a European country), it's really not that strange to give more attention to the more local subject. \n\nI teach history in Norway, and at least the history book that is used at my school doesn't *only* focus on the holocaust. The World War Two section has parts about atrocities on the Eastern Front, the holocaust, Allied terrorbombing/firebombing and Japanese atrocities in Asia. The holocaust part *is* larger than any of the others, but that's not really so strange considering some Norwegians were caught up in it.\n\nHistory teaching isn't really about finding the \"most cruel\", but the most relevant and relatable."
]
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1vdieb | Can you please explain the approach orbit for Rosetta to the comet it is landing on on Jan 20? (Link, Video inside) | Seen here: _URL_1_ and directly on YouTube here _URL_0_
The spacecraft approaches in this weird triangular orbit with almost-straight lines. I assume there's a burn at each of these points but that is a lot of changing direction for I'm not sure what purpose. Do you think it's needed for 3D imaging the comet as much as possible? | askscience | http://www.reddit.com/r/askscience/comments/1vdieb/can_you_please_explain_the_approach_orbit_for/ | {
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"Based on the [mission profile](_URL_0_) it appears that you're right that it is for imaging the comet. Primarily for the purposes of finding a safe way to approach the comet through the debris and then to find a suitable landing site.",
"The video you posted is a stylized representation of Rosetta's approach of the comet. That type of video is meant to provide a sense of the mission without providing real numbers or sense of time or scale. Some annotation would have been nice.\nSimilarly, this video shows the craft's journey from earth to the comet (note the gravity assists off Earth and Mars): _URL_0_\n\nThere is a full mission profile here; it is an outline which is being filled in as each portion of the mission is accomplished: _URL_1_\n\nExcerpt:\n\"The spacecraft reaches the comet on 22-May-14 at a distance of 4.0 AU from the Sun. A sequence of four rendezvous manoeuvres within 30 days reduce the relative velocity with respect to the comet from 780 m/s to 50 m/s. The spacecraft is in active cruise mode. During this phase Rosetta approaches the comet without observing the comet with the navigation camera (NAVCAM). The comet orbit is determined by a dedicated ground-based astrometric observation campaign. The errors in the estimated position of the comet can still be several tens of\nthousand km. The final point of the NCD phase is the Comet acquisition point (CAP) at 100000 km distance from the comet. The selection of this position depends on two factors: avoiding cometary debris (assuming there is any), and achieving good comet illumination conditions.\"\n\nAll this happens before the craft turns on its cameras. The final ~100000km to the comet will be done with camera assistance.",
"One other thing to keep in mind, this is not like orbiting a planet. The gravitational pull is minuscule in comparison. Instead, think of this as drifting back and forth along the line of advance of the comet. The directional changes are not going to require a lot of energy."
]
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"http://www.youtube.com/watch?v=GRjdqUDU3yI",
"http://gizmodo.com/watch-how-the-rosetta-spacecraft-will-orbit-and-land-on-1502508124"
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"http://starbrite.jpl.nasa.gov/pds/viewMissionProfile.jsp?MISSION_NAME=INTERNATIONAL%20ROSETTA%20MISSION"
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|
yhwua | What are some interesting or thought provoking ways to explain just how large the Universe is? | I love thinking about the vastness of space. | askscience | http://www.reddit.com/r/askscience/comments/yhwua/what_are_some_interesting_or_thought_provoking/ | {
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"text": [
"[This](_URL_0_) article has what you're looking for. There is more info of the picture at the top [here](_URL_1_)."
]
} | [] | [] | [
[
"http://astronomycentral.co.uk/how-big-is-the-universe/",
"http://www.youtube.com/watch?v=oAVjF_7ensg&feature=player_embedded"
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|
7vxj33 | why does the vision darken and limbs become shaky when we slip? | for example, slipping on an icy road or wet floor. wouldn't the opposite response of the body be more useful? like helping to grab on something or regain balance instead of this completely useless reaction. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7vxj33/eli5_why_does_the_vision_darken_and_limbs_become/ | {
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"text": [
"This is part of the adrenaline response; your brain narrows vision (so you can focus on a threat), enhances strength and speed for gross motor functions like swinging a weapon or running (at the expense of fine motor control, so you get shaky), and constricts blood flow to extremities to reduce the risk of bleeding out from a wound to the limbs (again causing some shakiness).\n\nFor the specific use-case of slipping, this isn't particularly helpful, but in the case of a predator or lethal fight with traditional weapons, this is incredibly useful. But for modern day, situations like this don't come up for most people, and when they do, we're typically using a firearm to deal with the threat, and this is something that needs to be worked around anyway.\n\nBasically it was evolutionarily useful for millions of years for mammals to have this response, and only in our very recent history has it become more of a hindrance than a help."
]
} | [] | [] | [
[]
] |
|
1j9bop | How do two-dimensional objects (like strings) have mass? | askscience | http://www.reddit.com/r/askscience/comments/1j9bop/how_do_twodimensional_objects_like_strings_have/ | {
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"I'm not familiar enough with string theory to really answer your question, but I will say that I think you're letting your physical intuition get in the way here. Mass is not a priori related to volume; that's just how we normally observe things on scales we interact with.\n\nIn fact, most particle physics theories theorize that [elementary particles](_URL_0_) like the electron are *zero-dimensional*, having no spatial extent whatsoever. The electron, of course, has a finite non-zero mass. "
]
} | [] | [] | [
[
"https://en.wikipedia.org/wiki/Elementary_particle"
]
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||
4q6fte | Why does the behavior of an airflow going through a nozzle changes between subsonic and supersonic speeds? | I'm currently follow an aircraft technician course and, during the engine section, we see how a turbine engine works and how the airflow is affected by convergent and divergent nozzles at subsonic and supersonic speeds. However, my classmates and I cannot quite understand why the air behaves differently between those two speed ranges, so if anyone could help us understand better this would be very much appreciated. | askscience | https://www.reddit.com/r/askscience/comments/4q6fte/why_does_the_behavior_of_an_airflow_going_through/ | {
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"At supersonic speeds, the air expanding through a nozzle doesn't know about air outside.. meaning the molecules expand as if it were a free expansion until they interact with the surroundings. This results in a shockwave as molecules rapidly equilibrate with the surroundings. Behind the nozzle and before shockwaves (barrel shock and Mach disk), is 'the zone of silence', where supersonic flow continues unimpeded. \n\nIn subsonic expansions, the air pressure transition is continuous and smooth because the molecules outside 'communicate' with the molecules inside.\n\nI would recommend reading:\n\n Atom, Molecule, and Cluster Beams I: Basic Theory, Production and Detection\n\nBy Hans Pauly for more info \n\n",
"I'll try and put it into an easy to understand form, without big messy equations here (unless you want them). It all comes from conservation of mass and how flow behaves in various regimes. Mass flow is the product of density, velocity, and cross sectional area. In low Mach number regimes, density changes is small and velocity change is large. So if you drop area, to conserve mass velocity goes up. Increasing velocity drops pressure due to conservation of energy (pressure potential energy turns into kinetic energy), so density has to decrease slightly in this regime when area decreases. When mach number exceeds 1, density changes become dominant now. So increasing area causes density to drop. Velocity has to increase due to energy conservation. So really it's because at low speed (mach under 1) density follows velocity, but at high speed velocity follows density."
]
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|
5wj3sr | use of term "Italy" and the italian identity since the fall of Roman Empire up until the unification | My questions is was the term Italy and Italian people used in the medival kingdoms of Europe and among the city states and duchys of the italian peninsula or were there clear separations between Venice,Genoa,Ferrara,Napels, Papal State etc. Did they have a sense of common identity?
| AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5wj3sr/use_of_term_italy_and_the_italian_identity_since/ | {
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"After the fall of the Roman empire, Italy continued to a more or less unified and autonomous polity until the 8th century, and would not become definitively fragmented until the 10th. \n\nAfter the fall of the Second Kingdom of Italy, the word \"Lombard\" (after the ethnicity of the old ruling class) denoted anything indigenously Italian in both north and south (\"Frankish\" was anything associated with the new ruling class). The earliest examples of what can be called written Italian appear in Benevento in the ninth century, while the nearby \"Lombard\" city of Salerno would become a major Mediterranean entrepôt and come to house a renowned University. \n\nIn northern Italy, after the wars of succession following Charlemagne's death, the Kingdom of Italy was given to Lothair (a grandson of Charlemagne) in 795. The unstable transitions between emperors in the Carolingian dynasty would ended in 887, after the deposition of Charles the Fat. Charles was the last Emperor to simultaneously hold the title of King of Italy, France, and Germany, and had even been elevated to the Imperial Throne from the position of King of Italy. However, he possessed no direct heirs, and the fight between innumerable female-line descendants was on.\n\nThe Marquis of Ivrea managed to get crowned King Berengar II in the late ninth century, however it wouldn't be long before the German Kaiser Otto decided to take the crown for himself.\n\nThe Ottonian Emperors Otto I, Otto II, Otto III, and Henry II would all travel to Italy to be crowned King of Italy by an Italian Bishop. Absurdly, the Ottonians came to rely on Italian revenues to contrast the unruly vassals in Flanders, Bavaria and Luxembourg. With the Italian lords having fought themselves into irrelevance in wars of succession of the early tenth century, Italy came to be one of the most centralized parts of the Empire. This arrangement would last until Henry II died without issue in 1024. And here it gets interesting, because although Conrad the Salian is elected emperor with minimum fuss in Germany, in Italy his ascension is not entirely recognized.\n\nThe Ottonians understood Italy, especially thanks to Otto II's marriage to the Byzantine princess Theophanu, but the same could not be said about the Salians. Almost as soon as Conrad II was elevated to the throne, his legitimacy in Italy was contested. Conrad condemned the \"Lombards\" in court, but no punitive action was taken: the lack of a strong landed aristocracy meant that Conrad had no military means to counter Italian cities doing as they pleased without transporting knights over the Alps. After Conrad convened a synod in Pavia to hear out the complaints, he got so infuriated by the dissidence of the Italian leaders he ordered the arrest of the bishop of Milan Aribert of Intimiano. However, imperial influence in Italy had almost completely eroded: Aribert fled back to Milan unhindered. Conrad tried to forcefully enter the city to seize him, but couldn't round up enough support. It would seem, then, that the Kingdom of Italy was ungovernable.\n\nIn between the eleventh and fourteenth centuries, when the Italian cities established themselves as self-governing but didn't yet evolve into states with jurisdictions beyond their city walls; so although Italy certainly continued to exist as a geographic and political construct, identity was most definitely tied to one's city or region. One of my favorite quotes from the Divine Comedy reads as follows:\n\n*Non omo, omo già fui, e li parenti miei furon lombardi, Mantoani per patria ambedui*\n\nThis is Virgil introducing himself to Dante. Virgil says, \"Man I am not but man I once was, my parents were Lombards, Mantuans by homeland both.\"\n\nDante commits an anachronism; Lombards wouldn't arrive in Mantua for hundreds of years at the time of Virgil's birth. But what's interesting here the way Dante calls \"Lombards\" the inhabitants of Northern Italy as late as the fourteenth century. \n\nBut specifying \"Lombard\" isn't enough, Dante finds it necessary to affirm that Virgil's parents are both \"Mantuans.\" So here we have a demonstration as to how identity on the peninsula is mostly tied to the urban communities. \n\nIt's important to reaffirm that the concept Italy never disappeared: In the second decade of the fourteenth century, for example, Boccacio would write that Canagrande Della Scala (Lord of Verona) was \"One of the most notable and magnificent lords known in Italy since the Emperor Frederick\" while the poet Niccolò de' Rossi affirmed that Canagrande \"Will be king of Italy by next year\" (Canagrande dropped dead at forty and did no such thing, but that's not the point).\n\nFast forward to the Battle of Fornovo in 1495, when the Italian states chased the already retreating Charles the VIII of France from Italy. Duke Lodovico Sforza of Milan and Pope Alexander had asked Charles to conquer the Kingdom of Naples, but then freaked out when he actually did conquer the Kingdom of Naples. They then set up a league to stop him (long story). After the battle, Milan made a hasty separate peace at Vercelli; and \"Treachery!\" cried the other members of the League, who then snubbed Milan (who had born the brunt of the fighting) and proclaimed the Republic of Venice \"Liberator of **Italy**\" after Charles was forced to hand the Kingdom of Naples back over to King Alfonso after his Alfonso's son Ferrante landed in Calabria at the head of an army courtesy of his Spanish cousins.\n\nFast forward again to the negotiations ar the Peace of Utreicht after the War of Spanish succession in 1713, and the Venetian Ambassador Carlo Ruzzini reported that the Republic of Venice was seen as \"*La Principale Potenza e Protettrice d'Italia*\" or \"Principal Power and Protector of Italy.\" \n\nSo clearly, the notion of \"Italy\" doesn't seem to have mutated in the two hundred years since the solidification of the half dozen independent polities on the peninsula, although the concept of Italian identity would only be formed after Napoleon's conquest of the peninsula. However, even during the *Risorgimento* (the Italian Unification process) Camillo Benso of Cavour, the Prime Minister of Piedmont (the Italian state which conquered the peninsula) would have been perfectly content with stopping at the conquest of Rome. It's a strange set of circumstances which led Garibaldi and his Redshirts, who were fundamentally paramilitaries, to organize their expedition conquering the south of the Peninsula. However, conquer they did, and \"Italy\" now refers to the entire peninsula and the state that governs it. \n"
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2dllbh | Outdoors, sunscreen wears out and needs to be reapplied every 2 hours or so. If you wear sunscreen indoors (away from UV radiation), does this same time limit on effectiveness hold? | Is the life of sunscreen extended somewhat (say 6 hours) but still needs reapplying before going outside (if longer then that limit)?
I tried to find information on this but couldn't. | askscience | http://www.reddit.com/r/askscience/comments/2dllbh/outdoors_sunscreen_wears_out_and_needs_to_be/ | {
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"This is only true for organic sunscreens like avobenzone, but inorganic sunscreens like titanium dioxide or zinc oxide hold up a lot better.\n\nBut back to your original question.\n\nNo, it's the UV light that is absorbed and causes the molecule to breakdown. UV light is higher in energy than visible light, which in normal cases doesn't have enough energy to break chemical bonds (there are cases in which is does, but for the most part it doesn't.) \n\nHow do we know organic sunscreens don't absorb visible light? It's because they are clear. If they absorbed visible light we would see them as colored. If the light isn't absorbed, it's not having a substantial effect.",
"The main reason to re-apply sunscreen, as I understand it, is because it is lost or washed away by swimming, sweating or friction from clothes. You may sweat less indoors, leading to less need to re-apply, but I image the others still apply."
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[],
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1chojc | If I were to point a massive radio telescope at the moon, what would it pick up? | askscience | http://www.reddit.com/r/askscience/comments/1chojc/if_i_were_to_point_a_massive_radio_telescope_at/ | {
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"Radio signals from Earth.\n\nAmateur radio operators do this often (though with much more modest hardware). It's called [Earth-Moon-Earth or EME](_URL_0_) operation."
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1l16fb | If stitches are meant to fuse your skin together across an open wound, could you then feasibly fuse your skin together with another person's skin? | I think the title says it all. Just got stitches done in my finger which prompted this thought. Is there something inherent in our own skin that will enable it to fuse with itself, or can one's skin just as easily recognize and accept another's? Thanks. | askscience | http://www.reddit.com/r/askscience/comments/1l16fb/if_stitches_are_meant_to_fuse_your_skin_together/ | {
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"Wouldn't that be a skin graft? Your body heals much faster with its own skin. It will attack foreign materials meaning other people's skin as well. Usually they will grow your skin if you need something that serious. ",
"if the blood and HLA types match, this is, there is no acute rejection (no immflamatory/immune response against the foreign tissue), then YES, it can \"fuse\". Nonetheless, with the time, it will develop some degree of rejection.",
"Stitches don't fuse the skin. They hold skins edges in close proximity so that healing will take place."
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5to9o2 | how does mobile "direct deposit" work for checks? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5to9o2/eli5_how_does_mobile_direct_deposit_work_for/ | {
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"You take pictures, you enter amount, you send it in. They use a computer to analyze the check and the serial numbers to see if it's a true check, they also check the amount as well of course.",
"These days, banks process checks between them by transmitting images of them, or even just the key numbers on them. It was getting too expensive (and slow) for the receiving bank to physically return the checks to the originating bank.\n\nSo you're just taking the same digital image your bank was going to take anyway."
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s96u2 | does an orchestra actually pay attention to the conductor? | I know I'm gonna get the die hards going berserk over this, but seriously...do they really? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/s96u2/does_an_orchestra_actually_pay_attention_to_the/ | {
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"In a sense, yes. \n\nThe orchestra as a whole is like the conductor's instrument. A living, breathing, instrument. He or she has some creative authority over the performers, and can mix up the pieces the orchestra is playing at will.\nThis doesn't necessarily mean changing actual notes in the piece, but adding his or her own flair to them. \n\nThe conductor sets the tempo, the level of energy, and minute details like how long a note is held. There are accent marks in the music like [this](_URL_0_) that indicate when change is likely going to appear, so the orchestra has an idea of when these changes might happen. \n\nThere's a fair amount of rehearsal that goes into a performance as well, so for the most part, they know how the conductor would like the piece(s) to be played. \n\nThe performers must multitask throughout the whole performance. They keep their attention focused on both the conductor and the sheet music in front of them. Most music stands are set at an angle from the performers perspective to make this easier.\n\nI hope this helps! (: ",
"This was explained in detail recently by [someone in a response to _URL_1_](_URL_0_)\n\nHere's an excerpt, but do read it all at the link for a lot more interesting details.\n\n > You're absolutely right that one of the main things an orchestra conductor does is to prepare the orchestra in rehearsal for the way he/she wants the piece to sound in performance. A lot of stuff is conveyed in that way that the conductor then won't need to attempt to convey in real time during the performance. And furthermore, as you suspect, conductors are often in some sense kind of \"dancing\" for the audience during performances, in ways that are strictly superfluous to making the musicians play correctly, though sometimes an enjoyable part of the concert experience."
]
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2zxvk6 | What was the international reaction to the Franco-Prussian War? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2zxvk6/what_was_the_international_reaction_to_the/ | {
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"Which parties in particular are we talking about internationally? The traditional great powers of Europe? The Franco-Prussian War was an epoch-defining event that shook up the traditional order in central Europe, which allowed the Prussians and the North German Confederation to formally unite the southern German kingdoms of Württemberg, Baden, and Bavaria into a single, German state. Any balance-of-power equations that would have existed prior to 1871 about a fractious, disunified Germany, would have to have been re-evaluated.\n\nAn important aspect of why there was little fervor to really intervene on the side of France during the war was because of diplomatic maneuvering on the part of Prussian Chancellor Otto von Bismarck to diplomatically isolate France by the time the war broke out in 1870, and his diplomatic baiting with the [Ems Dispatch](_URL_5_), France declared war upon Prussia, making it seem the aggressor. That, and the part of French diplomats about \"restoring France to its natural borders\" to the Rhine river in the events leading up to the war, also did not help France's image as the victim, especially as the war turned decisively against them in the [Siege of Metz](_URL_2_) (trapping 200,000 French troops), and the disastrous [Battle of Sedan](_URL_0_), which saw the capture and surrender of 120,000 French troops and the capture of their leader, Napoleon III.\n\nBecause of France's prior actions in the 1860s under Napoleon III's foreign policy, they alienated the Austrians by aiding the Italians in their [Second War of Independence (1859)](_URL_3_), which saw the Austrians lose territory to the nascent and newly-unified Italians. Bismarck's diplomatic maneuvering kept Russia nominally friendly or at the very least neutral against Prussia when they went to [war with Austria in 1866](_URL_4_), which culminated in Austria's loss of influence with the other German minor states, opening up the path to unification under the \"Little Germany\" unification idea, which was Germany without Austria.\n\nFrance's foreign policy also alienated Britain, in that their colonial conquests and foreign policy tended to be anti-Britannic, which was the traditional mode of thought for Franco-Briton enmity at the time, and has existed for centuries up until that point. After Prussia's victories in 1866, and Bismarck's vague promises of compensating Napoleon III for guaranteeing French neutrality while the Prussians curbstomped the Austrians, France saw itself somewhat swindled by the current state of affairs in the period between 1866-1870 - suddenly, to their east, was a large country that was more politically unified than ever before, and worse, had a professional military with reserves that they can mobilize that can outnumber their men in the field. \n\nCompound this strategic reversal on the map of Europe was the fact that France had very little to count on from the other European powers:\n\n- Britain was cold towards France as was the usual case. France was seen as the \"biggest threat\" to Britain, and despite their cooperation against Russia in the Crimean War, there were a series of naval arms races between the two countries that made relations cold.\n\n- Russia was not friendly towards France because of the latter's involvement in the Crimean War, easily within living memory of the statesmen of the time, not to mention Napoleon III was seen as one of the arch-architects of organizers of the coalition against Russia during that war.\n\n- Austria certainly could not be counted on due to their recent reorganization in having to make [political concessions to their Hungarian counterparts](_URL_6_) after the disastrous war of 1866 left the Austrians militarily and politically impotent during the 1870 war.\n\n- The United States was not going to be involved, they just emerged from their Civil War in 1865, and not to mention they were not in any power to mount any kind of military expedition in the aid of France.\n\n- Italy might have been the only state that could have helped France, but they were also recently unified and consolidating. However, France was still guaranteeing the security of the Pope in Rome, and Italian nationalists yearned to make Rome their capital. When the war broke out, the French withdrew their Roman garrison to reinforce the mainland, and the Italians promptly occupied Rome. However, there were Italians who did not forget France's part in aiding the Italian unification efforts of 1850-1860s, and there were those who joined on the side of France during the war, such as the Italian patriot Giuseppe Garibaldi, who led a [volunteer force](_URL_7_) to aid the French.\n\n- Spain did what it did best in the Nineteenth Century - which was to stay neutral of Continental European affairs in a large part.\n\nThe Prussians understood that the war had to be kept short and the overall strategic objective was to secure German unification, and that meant defeating France, whose interests were not served by a strong, unified Germany, which would replace France as the pre-eminent European land power. Bismarck himself even said he did not want Germany to annex the French provinces of Alsace and Lorraine, judging (correctly) that this would lead to a permanent enmity with France, but the German nationalists and German military leaders won that debate in arguing that Alsace-Lorraine was populated by ethnic Germans, and the military leaders arguing that they wanted a strategic buffer on their western frontier controlled directly by the central government in Berlin. This enmity between France and Germany would be one of the culminating causes of World War One, and Bismarck's diplomatic policies of keeping France diplomatically isolated ended with his dismissal in 1890, with Kaiser Wilhelm II's \"zig-zag\" foreign policy achieving relative diplomatic isolation on the part of Germany when [France and Russia formally concluded a military alliance in 1892](_URL_1_), thus surrounding Germany with potentially hostile powers on two fronts - something Bismarck feared the most, and had come to pass.\n\n\nTLDR; brilliant diplomatic maneuvering on the part of Bismarck and alienating French foreign policy by Napoleon III in the years leading up the the 1870 war left the French diplomatically isolated and effectively gave the Prussians a free hand in defeating the French. "
]
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"https://en.wikipedia.org/wiki/Franco-Russian_Alliance",
"https://en.wikipedia.org/wiki/Siege_of_Metz_%281870%29",
"https://en.wikipedia.org/wiki/Second_Italian_War_of_Independence",
"https://en.wikipedia.org/wiki/Austro-Prussian_War",
"https://en.wikipedia.org/wiki/Ems_Dispatch",
"https://en.wikipedia.org/wiki/Austro-Hungarian_Compromise_of_1867",
"https://en.wikipedia.org/wiki/Army_of_the_Vosges"
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cythuo | why you're more likely not to keep weight off if you lose too quickly? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cythuo/eli5_why_youre_more_likely_not_to_keep_weight_off/ | {
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"Because loosing weight is relatively easy. Do some things, avoid certain things-soon enough you'll lose weight.\n\nKeeping the weight off is a lifestyle change. Do those same things, avoid those same things, and repeat for the rest of your life.\n\nDiscipline is one thing to lose weight. Maintaining that discipline is commitment to keep the weight off.",
"If you're rapidly losing weight, you're likely making drastic lifestyle changes, quickly. Such as going from working a sedentary job and eating garbage every day without keeping track of what you're eating, to working out 5 times a week, eating much healthier, tracking all your calories, etc. \n\nMost people can't do a complete 180 in their life, and stick with it for the rest of our lives. Habits take time to form, and the more you're taking on at once, the harder it will be to stick with it."
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3lupzd | Is there an equation which from the number of carbon atoms in an alkane would give the number of constitutional isomers? | This is a problem that I have struggled with for a few weeks to no avail. I have failed to find any equations which successfully predicts the number of constitutional isomers from the carbon number but it seems to me that there must be a relationship as it is the number of carbon atoms which allows for the increasing number of constructions. Thank you for any help on this matter. | askscience | https://www.reddit.com/r/askscience/comments/3lupzd/is_there_an_equation_which_from_the_number_of/ | {
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"This is \"just\" enumerating the trees with a given number of vertices and of maximum degree 4, up to isomorphism. OEIS has this sequence as [A000602](_URL_0_), and links some variants. \n\nAt a certain point you have start thinking about stereo-isomers (for example C(CH3)(C2H5)(C3H7)(C4H9)) and after that you start running into isomers which have space problems, like C(C(CH3)_3)_4 where the hydrogens seriously start bumping into each other."
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2yor0u | why do cable companies like comcast and time warner advertise so much if they have no competition? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2yor0u/eli5_why_do_cable_companies_like_comcast_and_time/ | {
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"They have lots of competition. Every home that has a clear view of the southern sky has the option to get their television via satellite.",
"For the same reason Kim Jung Un puts out propaganda in North Korea",
"Tv services has significant competition. It is cable interent, that most providers have limited to no competition. Though, they are still competiting with dial up a little. ",
"They do have competition from Direct TV, Dish, Antenna, and Internet. ",
"From a management standpoint its economical. You spend \"X\" amount of dollars to get \"Y\" amount of return. Return here being customers and their money. This system simplifies decision making yet accounts for all the nuances of competition. So for time warner/Comcast, someone crunched the number and demonstrated that the amount of money spent towards advertisement despite their already having a large marketshare, I still worth it due to the return they get. ",
"They're trying to get people without cable TV to buy cable TV. They're trying to retain existing customers by selling them new packages that (depending on the company) can lock them into new contracts. Also, DirecTV and Dish are available if you don't have interference in your area for their satellites. ",
"Brand empowerment. Same reason why Coca Cola and McDonalds spend so much on advertising budgets despite being almost universally known corporations throughout the developed world."
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90dxzq | Would Earth's gravity have been different before we had a moon? | askscience | https://www.reddit.com/r/askscience/comments/90dxzq/would_earths_gravity_have_been_different_before/ | {
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"The Moon is likely to have been from the Earth - Earth got hit by some large object early on, and the resulting mess consolidated into two bodies. So the original Earth would have been more massive, and had stronger gravity.\n\nIf you're asking about whether the gravity of the Moon pulls us \"up\" away from the Earth, making Earth's gravity comparatively weaker, then that's a bit more complex. The Moon is pulling us on the surface *and* the Earth at the same time. So the only effect is the *difference* between how much the Moon is pulling us on the surface versus how much its pulling the Earth as a whole on average.\n\nIf you're on the side of the Earth directly underneath the Moon, then the effective gravity feels about 0.00001% weaker, and if you're on the side of the Earth directly *opposite* the Moon, then the effective gravity feels about 0.00001% stronger.\n\nObviously this isn't a huge effect. But this little difference is still enough to cause the tides to flow in and out."
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389g1y | how does water "reset" hair? | I have longish hair on top and a handlebar moustache and whenever either is acting up from sleeping on it weird, all I have to do is get it wet and it'll get rid of even the most intense bed head/'stache, but will refuse to cooperate even a little if it's dry the whole time. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/389g1y/eli5_how_does_water_reset_hair/ | {
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"Mustaches are naturally hydrophobic, which makes them extremely docile in the presence of water. The fear particles have probably migrated from your face to your scalp, resulting in the bizarre and unnatural phenomenon you describe. Each of your follicles is a living, sentient being, and when you shower you're essentially water boarding them all together.\n\nYou monster.",
"Hair follicles have very small scales on them. Hot water and friction (like lying on a pillow) will open up these scales and cold water will close them. This is what gives hair \"memory\" and why instruments like curling irons work. The curling iron opens up and re sets the scales in a \"curl\" position. \n\nWhen you wet your hair (presumably in warm water) and allow it to dry, you're resetting it's memory."
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2wc2vp | why does pepto bismal make the tongue and stools black and how does it cure diarrhea? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2wc2vp/eli5_why_does_pepto_bismal_make_the_tongue_and/ | {
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"Pepto bismol has a large amount of bismuth in it. Bismuth is a heavy metal and kills bacteria through heavy metal poisoning, but in the doses we take it doesn't cause any known harm.\n\nPoo comes out tarry and black because of the byproducts of killing bacteria, namely dead bacteria and a bunch of organic bismuth molecules.\n\nLook up how to purify bismuth from pepto on YouTube, pretty interesting videos showing how much metal there is in it."
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1rgy6n | Did Josef Mengele Ever Succeed in Any of His Experiments? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1rgy6n/did_josef_mengele_ever_succeed_in_any_of_his/ | {
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"No, because his premises were unscientific, his methods questionable and his experiments haphazard.\n\n\nFirst, many of the experiments were based on peculiar Nazi racial theories about who was \"Aryan\" and who was not. The issue of the existence of distinct human races is problematic and controversial in and of itself. Certainly, no contemporary scientist will agree that there is such a thing as the Aryan race. Obviously, which such a flawed premise, it is hardly surprising that the experiments yielded no results.\n\n > in 1944, he began his own project on twins, [...] **Were there reproducible racially determined differences in serum following an infectious disease?** [...] Dr Mengele infected identical and fraternal twins, Jewish and Gypsy twins with the same quantity of typhoid bacteria, took blood at various times for chemical analysis in Berlin, and followed the course of the disease. According to [Jewish inmate doctor and forced assistant) Dr Nyiszli, he also worked with tuberculous twins. [...] Dr Mengele's letters and reports to [Nazi research physician] Professor von Verschuer were probably destroyed by von Verschuer [who went on to pursue a successful academic career after denazification]. [...] Right up to the last moments of the war, Professor von Verschuer was still hoping for a major breakthrough. [...] **Dr Mengele and Professor von Verschuer did not solve their problem**. (Benno Muller-Hill, *Murderous Science*, 1998)\n\nFor more on the tuberculosis study in particular and why it was scientifically flawed for other than racist reasons, see Benno Muller-Hill, [*Genetics of susceptibility to tuberculosis: Mengele’s experiments in Auschwitz*](_URL_0_) (Nature, Vol 2, August 2001, pp 631-634). Essentially, Mengele and his supervisor **clung to an outdated theory**.\n\nMengele also used the twins in (extremely painful) experiments to try to change their eye colour, but failed. This was an attempt at research on phenogenetic eye pigmentation and eye colour heredity. A particular Nazi focus was to find out **whether the structure and colour of the eye could be used to determine the \"race\"** (Jewish or Aryan) of the subject. (Benoît Massin, *Mengele, die Zwillingsforschung und die „Auschwitz-Dahlem Connection\"*. In: Carola Sachse (Ed.): *Die Verbindung nach Auschwitz. Biowissenschaften und Menschenversuche an Kaiser-Wilhelm-Instituten. Dokumentation eines Symposiums.* Göttingen 2003)\n\nSecondly, many \"experiments\" seemed to have sprouted from an impulse of the moment and were not part of an integrated study as were the two experiments described above. No original paperwork survives on the other experiments, we therefore rely on a great number of eyewitness testimony. Some of these bizarre experiments were: sewing twins together to create conjoined twins, surgeries such as organ removal, castration, and amputations.\n\nA symposium uniting experts from the field of law, history and medicine was held at the University of Minnesota in 1989 to discuss the Nazi human experiments. It had this to say about why Mengele's research was useless:\n\n > The experiments were carried out under circumstances that were scarcely representative of the normal human condition. The debilitated physical conditions of many of the victims most certainly confounded results from the experimental procedures. [...] \nThe absence of sound scientific reasoning or theory underlying the experiments. (Nancy L. Segal, *Twin Research at Auschwitz-Birkenau. Implications for the Use of Nazi Data Today*. In: Arthur C. Kaplan (Ed.): *When Medicine Went Mad: Bioethics and the Holocaust* 1992)"
]
} | [] | [] | [
[
"http://www.rci.rutgers.edu/~piecze/MengeleBennoMullerHill.pdf"
]
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||
7x5iws | Why are some ions more soluble than others? | Does it relate to periodic trends, or is it completely different for every ion? What causes this difference? | askscience | https://www.reddit.com/r/askscience/comments/7x5iws/why_are_some_ions_more_soluble_than_others/ | {
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"Generally solubility is determined by three different factors. How strongly the solvent binds to the ions, how strong the solvent binds to itself, and how strongly the ions bind to each other. \n\nIn order to dissolve an ion you have to break both ion-ion bonds and solvent-solvent bonds to form a bond between the ion and the solvent. If a ion isn't soluble it can be because the solvent-solvent and/or ion-ion bonds are stronger than the resulting ion-solvent bond thus making it more favorable for the ions to bind to each other instead of dissolving. \n\nThese factors are somewhat related to periodic trends, but periodic trends alone aren't enough to predict them. Ion charge, ion size, solvation shells, etc. play a larger role. This is especially true when you get into ionic molecules."
]
} | [] | [] | [
[]
] |
|
1k5g1d | Could radio waves be combined in such a way that a wave with increased frequency is created? | I don't know much about the physics of radio waves and so I don't know if or how their waves can combine, and if this can actually be used to increase the frequency. It seems like this should be simple to answer through a search but I didn't turn up much that was relevant, so any direction to finding an answer is appreciated! | askscience | http://www.reddit.com/r/askscience/comments/1k5g1d/could_radio_waves_be_combined_in_such_a_way_that/ | {
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"Check out the Wikipedia article about the[ superposition principle](_URL_0_) for answers.",
"Not in any linear way. That is, you can't just have some radio waves out and about, then add them together (like overlapping two beams) and get something with different frequency content than what went in. In fact, by superposition, a wave that is made from two waves is *precisely* the same thing as the two waves being in the same location. \n\nImagine you had a charged particle in the path of these radio waves. You could either figure out how the particle is going to react by calculating with the superposed wave or by calculating with each of the component waves and then summing the two answers. \n\nThere may be some weird metamaterials out there that have some frequency shifting properties, but I don't think that's what you're trying to get at. There's also mixing (what we do for AM or FM modulation), but that's a manmade, nonlinear, process. ",
"There are active [multipliers](_URL_2_), whose theoretical action is to take as input two sine curve signals *S1* and *S2* and output their product *S1* x *S2*.\n\nBy [trigonometric product to sum identies](_URL_1_), this results in the sum and difference frequencies. I wrote a document covering the trigonometry that [is posted online](_URL_0_).",
"Yes. Look up the following terms:\n\n[Intermodulation](_URL_0_)\n\nIntermodulation creates sum and difference products from the interaction of two or more source frequencies. Passive Intermodulation (PIM) is a common source of unintentional, potentially damaging noise in cell phone systems in which multiple carriers are transmitted in a single feed line and antenna system. Source: I'm an engineer that deals with radio noise elimination in cell phone systems.\n\n[Heterodyne](_URL_1_)\n\nHeterodyning is a signal processing method using intentional intermodulation, and is commonly used in some radio equipment.\n\n\n"
]
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[
"http://en.wikipedia.org/wiki/Superposition_principle"
],
[],
[
"http://www.scribd.com/doc/146191611/Quizzette-2",
"http://en.wikipedia.org/wiki/List_of_trigonometric_identities#Product-to-sum_and_sum-to-product_identities",
"http://www.minicircuits.com/products/Multipliers.shtml"
],
[
"http://en.wikipedia.org/wiki/Intermodulation",
"http://en.wikipedia.org/wiki/Heterodyne"
]
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|
1uz6b8 | Given Ariel Sharon's passing what is the current prevailing historiographical opinion regarding Israeli involvement/culpability in the Sabra and Shatila massacres? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1uz6b8/given_ariel_sharons_passing_what_is_the_current/ | {
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"Let's all go to this topic: _URL_0_"
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[
"http://www.reddit.com/r/AskHistorians/comments/1uyyyo/in_light_of_sharons_death_what_actually_happened/"
]
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||
1ug9r3 | Why was there such a connection between Russian and French culture in the 18th and 19th centuries? | I've noticed this in literature as well as the architecture of St Petersburg for example which resembles the architecture of Paris. I have also noticed that, living in an ex-eastern block state, a big portion of educated people of age 50+ are well versed in both French and Russian. Thus my question. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1ug9r3/why_was_there_such_a_connection_between_russian/ | {
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"text": [
"Interesting question, I'd like to know that too. BTW St Petersburg was built by Italian architects, so it's not specifically French I suppose.",
"The intellectuals in Russia saw the French as the high point of refined European (Western) culture at the time. By the late 18th and 19th century, they saw themselves as a backwards peasant state and aspired to the cultural accomplishments of a nation like France, and as such French became a de facto intellectual language (as it was in other parts of Europe as well), and elites began to imitate aspects of French culture. \n\nAs a personal aside, I've always found that Russian writers FAR outstrip French writers of the 19th century when they are writing in a way that strikes me as distinctly contextualized in a Russian context. But maybe that's just because I'm sort of existential like that."
]
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[],
[]
] |
|
fj7ws2 | why are aluminum and tin containers safe for long term storage of beverages and other food items? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fj7ws2/eli5_why_are_aluminum_and_tin_containers_safe_for/ | {
"a_id": [
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"text": [
"They have protective coatings on the inside that prevent corrosion and leaching. These coatings are tailored to suit the content a particular can holds as there is no one-size-fits-all."
]
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[]
] |
||
3akf0l | what donald trump thinks he can fix in america and how? | Yes, I am aware of how much of an arrogant wealthy douche Donald is.. But what does he really think he can bring to the office that would help the country flourish? What are his plans so far? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3akf0l/eli5_what_donald_trump_thinks_he_can_fix_in/ | {
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"He doesn't have a plan. He's not really even running for office. This is how he stays in the media spotlight and sells the Trump brand. It's for money. ",
"Trump is savvy enough to know he couldn't win a mayoral race. It's a ploy, cycle after cycle, to keep himself \"relevant,\" maximize his brand (which is himself) and massage his ego.\n\n This is a man who hired a P.I. to find Obama's Kenyan birth certificate and picked a public fued with Rosie O'Donnell. His actions would almost be performance art at this point if he wasn't so sad and self-important."
]
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[],
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|
w5l0d | Is there any scintific evidence that whales or dolphins will die or go deaf because of the US Navy's underwater sound system? | A friend sent me the following link with the subject line, "Is this true?" and the following link: _URL_0_
IMPORTANT: I'm not advocating that anyone sign this petition... I'm not taking a side regarding a need (or lack of need) for such a sound system, nor am I taking a pro or con stance regarding animal rights. I'm genuinely curious about the claims made in the petition. Are there any marine biologists and/or whale dolphin experts that might have some input? Heck, for all I know the whole US Navy underwater sound system thing is an internet hoax. Again, I'm just curious about the science behind the claims in the petition.
| askscience | http://www.reddit.com/r/askscience/comments/w5l0d/is_there_any_scintific_evidence_that_whales_or/ | {
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"[Wikipedia](_URL_0_) happens to have an article on this exact subject.\n\nSonar has a detrimental effect on marine mammals, but probably not as extreme as the petition suggests.\n\nThe primary concern appears to be preventing their communication and causing disorientation, which reduces their ability to hunt and locate others of their own species.",
"Some sonars, particularly low-frequency ones used by the oil industry, can damage marine mammal hearing. The details of this are complicated and not well understood, but are certainly being studied.\n\nIf an article starts with this, however:\n\n > Stop the killing of 1,800 whales and dolphins and the deafening of 15,900 more by ceasing the operation of the Navy's underwater sound system in the Hawaiian Islands, the California and Atlantic Coasts, and the Gulf of Mexico.\n\nThey're full of shit.\n\nEdit: Frequencies matter *a lot*. \"Whales and dolphins\" cover a frequency range of ~100 Hz to ~60 kHz. They're probably talking about a 3.5 kHz sonar, but they don't seem to have any clue, so it's hard to tell. Which animals are affected also matter. If you kill 2000 harbour porpoises, no one cares. If you kill 400 North Atlantic Right Whales, that's all of them.",
"[Here's a thread](_URL_0_) on this from a few days ago in r/oceans. It includes a link to a [_URL_2_ article](_URL_1_) which partly backs up the claims, however the numbers do not agree.\n\nThe navy (as well as the oil industry) does have sonar with sufficient beam strength to harm marine mammals if they are nearby. However, documented cases are rare, in part because the animals will swim away from the source if they are able. The Navy already has restrictions on where and when they can operate the most powerful sonars.",
"Not an expert on Underwater Bioacoustics, but I've at least had a class on the topic and follow the literature casually. The effects of anthropogenic noise on all marine life is a hot topic in the field, with new research coming out regularly. \n\nAcoustic systems have been known to impact whales and dolphins. Famously, a group of Cuvier's Beaked Whales were stranded after a sonar testing exercise ([article for that here](_URL_0_)). Animals have been known to change behavior, such as avoiding loud areas in the ocean, or even change their whale songs to respond to man-made sound sources.\n\nRecent studies suggest that high sound levels can cause air bubbles in the blood streams of the animals to come out of solution, which can injure or disorient the creatures. It's analogous to when humans get \"the bends.\" This is one of the possible causes for the whale stranding. Moreover, loud sounds can interfere with natural echolocation mechanisms that animals like dolphins use to feed themselves.\n\nFor anyone deploying underwater acoustic systems, it's important to analyze and understand the environmental impact of sound. This often involves finding a safe range from the source, determining how many animals are likely to be too close using population surveys, and using warning signals at a safe level to scare off any animals before turning the sound on at full power. Filing an EIS report can also be required, as referenced in that petition.\n\nThat said, the claims in that petition seem sensationalist, and it fails to reference the specific EIS report that gives those statistics."
]
} | [] | [
"http://signon.org/sign/navy%2Dunder%2Dwater%2Dsound"
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[
"http://en.wikipedia.org/wiki/Marine_mammals_and_sonar"
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"http://www.reddit.com/r/oceans/comments/vze71/us_navy_is_about_to_deafen_15900_whales_and/",
"http://phys.org/news/2012-05-navy-sonar-blasts-sea-life.html",
"phys.org"
],
[
"http://www.pelagosinstitute.gr/gr/pelagos/pdfs/Mass_stranding.pdf"
]
] |
|
2ujphq | why do airlines [some] price single tickets at huge premiums to return trips? | Surely passengers will book return trips and just not show up for the return leg. Leaving the airline with a no-show and empty seat they cannot sell (unless they are overbooking). Equally they are just throwing away potential business on oneway flights with crazy pricing. Budget airlines moved from the business model years ago, but the majors still stick to it. Why?
A perfect example: _URL_0_ | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ujphq/eli5_why_do_airlines_some_price_single_tickets_at/ | {
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"I don't work for an airline and so can't speak for why any one airline would act this way, but I would suspect that it's an attempt to segregate their customer base by price sensitivity.\n\nSomeone who is flying for personal reasons, or for pleasure, is going to be price sensitive; if they aren't presented with a price they like, they'll shop elsewhere, including budget airlines, or by changing the dates that they're flying on. As a result, major airlines would want to drive that price down and fly it at a discounted rate in order to drum up business.\n\nOne-way trips are more likely to be taken by either business customers or people with enough disposable income to not have a set itinerary on where they're going, or people who are permanently moving to a location. For those passengers, the cost of the flight is less important than the time of the flight. If I'm travelling for business and I need to get, say, from Chicago to San Francisco by Tuesday, I'm going to take the Monday night flight regardless of cost. I'm not paying for the flight personally; I'm going to expense it to the business, so I'm price insensitive. The airline can get away with charging me more money because I'm less likely to care about it, and I'm certainly not going to change the time of my flight over it.\n\nSimilarly, luxury hotels are more likely to [charge for wifi access](_URL_0_) than budget hotels for the same reason; their clientele is more likely to be travelling on business, charging the trip to their business and are therefore price insensitive. Or they're *choosing* to pay a huge amount for the room in the first place, so the hotel figures they won't even notice a small charge for the wifi. On the other hand, if you're at a Motel 6 and there's a Super 8 down the road that's giving away free wifi, charging for it is going to cause you to lose business.\n\nAside from that, if you're booking each half of the trip separately, you may decide to switch airlines for your return flight. If each leg is exactly half (let's say each leg is $500), then you may decide to give your $500 to United on the way out and the other $500 Delta on your way back. If, instead of $1000 for a round-trip, United cuts you a deal and offers $700 total, they're getting all of your money, and you're not giving any to a competitor. They're taking a guaranteed $700 over a guaranteed $500 with a possibility of another $500 later.\n\n > Leaving the airline with a no-show and empty seat they cannot sell (unless they are overbooking).\n\nSure, but they *do* overbook."
]
} | [] | [
"http://imgur.com/gallery/faLp65E/new"
] | [
[
"http://www.marketplace.org/topics/business/ive-always-wondered/why-do-luxury-hotels-charge-wi-fi-cheap-hotels-dont"
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|
4dwfnx | Was Alexander the Great a traditional conqueror or did he just go on a massive 13 year raid across the known world? | Since he spent all his time fighting and didn't really have any time left to act as a regular ruler, did the conquered people really feel like they were part of his empire or was it more of a "that guy kicked our ass, I hope he doesn't come back" type of situation? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4dwfnx/was_alexander_the_great_a_traditional_conqueror/ | {
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"Alexander's constant campaigning did indeed mean that he wasn't able to spend as much time ruling his domain as a less conquest oriented monarch might. But just how the conquered peoples felt about their new position is hard to gauge. In one sense it is reasonable to say that Alexander's new subjects would have been aware that they were under the rule of a new government as Alexander appointed many new Greek and Macedonian officials to rule in his new provinces. The most famous example would be Egypt where Cleomenes, a man from the local Greek colony of Naucratis, was appointed as the region's chief financial officer. He would go on to become the most powerful man in Egypt until Alexander's death, presiding over an extortionate and abusive regime. Macedonians such as Stasanor, Tlepolemus, Sibytius, Peithon, and Philip were all appointed to rule in the various provinces of the Far East. We don't know much of the regimes of these men although many lasted quite a long time after Alexander's death.\n\nBut would having a new Greek or Macedonian governor make that much of a difference to the conquered peoples? Taxes and tribute were still imposed, often at the same rate the Persians had set. The Persian administrative structure was kept in place, with the regional boundaries being organized in much the same way. Also Alexander did not appoint only Greek and Macedonian officials. In Egypt, a native named Doloaspis received administrative control of the country while Cleomenes was supposed to only act as a tax collector (a limitation he clearly ignored). Queen Ada continued to rule in Cardia, the Persian Phrataphernes was kept on in Parthia (and would stay there until 321). Other Persians like Mazaeus (who was given the governorship of Babylon but had two Macedonians acting as his general and tax man), Mithrenes (former Sardis governor sent to rule Armenia), and Abulites (ruling Susiana but again with Macedonians as his officials) all administered a great deal of territory for Alexander. In India, things can't have been very different at all. Much of Alexander's Indian empire was ruled by the local kings Taxiles and Porus as vassal states. Seeing as Macedonian rule east of the Indus had almost completely broken down by 315 one wonders what really changed administratively. \n\nOf course simply looking at the appointments Alexander made doesn't give us a complete idea of how his new subjects felt about whether they were truly part of a new Macedonian empire. Now it's entirely possible that people didn't think Alexander was coming back as he continued ever further into the east. On his return journey numerous governors were replaced for alleged mismanagement, suggesting that Alexander's officials were carving out their own fiefdoms before the man was dead. Some of this can be attributed to Alexander's ever increasing paranoia but there is some evidence that such acts of abuse were going on. Harpalus, a friend of the king's, eventually replaced Mazaeus in Babylon and went about debauching himself on the assumption that Alexander would never come back. He was forced to flee, taking a large quantity of embezzled funds with him, in 324. \n\nIn terms of what we can learn from all this it seems fair to say that while the conquered peoples probably had some idea that they were living under a new Greco-Macedoinan power structure, it's hard to be sure whether or not there was truly a sense of being part of a unified empire under Alexander. Whatever belief there was in such an entity certainly crumbled very soon after his death, as the empire gave way to the successor kingdoms. \n\nI hope this rambling answer has been somewhat informative. All the information I've referenced comes from Arrian's *Anabasis.* "
]
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[]
] |
|
4ernku | Can the Western Roman Empire be considered a state? | Using the definition of the state as "a nation or territory considered as an organized political community under one government", can the Roman Empire, particularly of the late antiquity, be considered a state?
| AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4ernku/can_the_western_roman_empire_be_considered_a_state/ | {
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"Why wouldn't it be considered one? \n\nI know this is a problematic set of criteria, but it's what my university teaches its undergrads. A state has\n\n1. visible class distinctions\n2. monumental archetecture\n3. complex record keeping (when I started my grad program we said \"writing\" - but that turned out to be so problematic the prof changed it)\n4. agriculture\n5. centralized political structure\n\nAgain, hugely problematic. But Rome fits those things.\n\nThe question I see more often (perhaps because of my research) is whether Rome can be considered a nation-state, and the consensus is that it can't be. There are a number of different theories about nation-states and nationalism, and almost all of them make nation-states things of modernity. People do argue about whether the state produces the nation (I think that's the direction Weber, *Peasants into Frenchmen*, takes) or whether nationalism produces nations (Benedict Anderson? I forgot who I read on Italian nationalism that argues this way).\n\nThere is a guy, Antony Smith, who argues that nations could and did exist in the ancient world. He picks Jews and Armenians for that. It's been a while since I looked at his stuff. I don't remember the Armenian argument very well. The Jewish argument had to do with the centrality of cult practice at Jerusalem (or lack thereof after 70 CE) - it provided an anchor in a shared imagined history linked with a homeland either currently or previously occupied and continuously remembered by a population that recognized itself.\n\nRome never got that. I would argue it came close with the Social War, Augustus' use of *tota Italia*, and some other similar things, but it never really sunk in."
]
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] |
|
oq7ey | Does the fibonacci sequence really show up that often in nature, or is just an example of some sort of paradolia? | askscience | http://www.reddit.com/r/askscience/comments/oq7ey/does_the_fibonacci_sequence_really_show_up_that/ | {
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"[This article](_URL_0_) summarizes it well.",
"[This is the best explanation](_URL_2_) of why fibonacci numbers show up in nature so often that I've seen. Sorry that it's not from a scientific source, but it is still very interesting. That was Part 2 (which deals with Fibonacci numbers in nature), here is [Part 1](_URL_1_) (which explains the fibonacci sequence) and [Part 3](_URL_0_) (which deals with other patterns similar to the fibonacci sequence in nature and possible reasons of why it happens). \n",
"This series of videos shows why Fibonacci spirals tend to form in plants. Skip to the third one for the underlying biological reason:\n\n_URL_0_\n\n_URL_1_\n\n_URL_2_"
]
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"http://www.youtube.com/watch?v=ahXIMUkSXX0&list=LLDH_oPEjkhAeHuArSoTUe4Q&index=5&feature=plpp_video",
"http://www.youtube.com/watch?v=lOIP_Z_-0Hs"
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[
"http://vihart.com/blog/doodling-fibonacci-1/",
"http://vihart.com/blog/doodling-fibonacci-2/",
"http://vihart.com/blog/doodling-fibonacci-3/"
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||
bqf89e | why usual purchases with a card need something memorable (pin code), but online purchases have their secret code printed right on the card? | The way I understand, the usual (non-contactless) payment is a prime example of 2FA: you present your card, and then either sign or enter PIN code. First option ticks something you have (card) + something you are (the person who can white a signature matching the card's one), second - something you have (card) + something you know (PIN code).
I get that online purchases can't match the signature - but why between PIN and CSC you'd pick the latter as a security measure? It reduces the security to single factor (if I steal a wallet I can spend all the money on the card until it's blocked, having the object is all I need), and doesn't even add any speed to the transaction. What's the benefit of CSC as the verification? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bqf89e/eli5_why_usual_purchases_with_a_card_need/ | {
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"This is something that is changing in the EU. They are going to add in 2 factor authentication for cards. For example one of the cards I have requires me to unlock my banking app using my pin or fingerprint and approve the transaction. \n\nEffectively requiring someone to steal and unlock your phone and card.\n\nCurrently it's not uncommon for Visa or Mastercard to add a secondary check where you enter a password as part of the transaction.",
"Post about it from 3 years ago that go over a few points:\n\n_URL_0_"
]
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"https://www.reddit.com/r/explainlikeimfive/comments/44dza4/eli5why_pin_does_not_required_for_online_shopping/"
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1k56ms | social darwinism | Tried Wikipedia but it makes no sense whatsoever to me. Any explanation would be great. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1k56ms/eli5_social_darwinism/ | {
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"It's the application of Darwin's \"evolution of species\" to the society. Some philosophers wrote about a link between the evolution of species (larger wings, ability of changing colour etc.) and the evolution of society. They referred mainly to capitalist society. This meant that the stronger had the right to \"survive\" and to colonize other kind of societies considered as inferior. This stream of thought brought to colonialism, imperialism, and all sort of discrimination",
"Social darwinism is an attempt to use Darwin's idea of natural selection, or \"the survival of the fittest,\" to explain or, in my experience usually *justify*, the mistreatment of one group of humans by another. In normal polite discourse, it is almost never a good thing to be accused of being a Social Darwinist. Social Darwinism has an ugly history of being used to justify mistreatment of groups of people and even genocide. People who may subscribe to some ideas of Social Darwinism usually don't like to use the term because of the ugly connotations.\n\nHere's an example: why are some people poor? The Social Darwinist would say some people are poor because they are dumber, lazier, or otherwise not as capable of competing with smarter, harder working, *richer* people. Similar to how natural selection causes less fit types of organisms get outcompeted by more fit ones, the Social Darwinist would believe that poor people will over time be removed from the gene pool because they cannot compete with the people who are more fit. Basically, survival of the fittest for humans.\n\nHere's where it gets really ugly. If you believe in survival of the fittest for humans, you might think it is in humanity's best interest and therefore your duty to oppress or even kill the \"lesser people.\" This leads to all kinds of persecutions. How do groups wind up on the list of \"lesser people?\" Usually, historical biases. Nazi Germany is sometimes considered to be a Social Darwinist regime (there is some debate about their motivations). They believed the Aryan race to be superior to the Jews and gypsies and actively tried to kill them. By exterminating the undesirables they believed they were making the gene pool stronger. So Social Darwinism became a justification to murder millions of people they didn't like. It is pretty easy to see how Social Darwinism can be used to justify genocide.\n\nIt isn't just genocide though. This principle was used to justify colonialism and imperialism as well. As with people and gene pools, it was believe that stronger cultures would dominate over weaker cultures. The prevailing thought was that Europeans and European culture were superior and therefore it was desirable that they ruled over other groups of people and destroyed their cultures.\n\nIn a nutshell, under Social Darwinism if you don't like a group of people you can justify your mistreatment of them by saying that you are strong and they are weak. Therefore, it's a *good* thing when you mistreat them or kill them. This is all sorts of awful, and why Social Darwinism gets a bad rap.",
"\"Social Darwinism\" is paired with \"survival of the fittest\" and both have no connection at all to Darwin's theories of how organisms evolve over time. The movement is a hodgepodge of ideas from social \"scientists\", political philosophers and social groups that steals credibility by associating itself with the great biologist while having no actual connection to biology or evolutionary theory.\n\nBasically the theory is that certain segments of society have \"evolved\" to be less fit to survive and are thus dangerous, poor, uneducated, have no technology, etc. It explains away social, political and other complex factors involved by pointing to genetics and shifts blame from oppressor to oppressed. The theories have been used as justification for terrible acts ranging from institutionalized segregation to genocide.\n\nIt's complete discredited bullshit conjured and nurtured and often still accepted by elitists who distance themselves from the concept in public while absolutely subscribing in private. Mitt Romney comes to mind.\n\n",
"I hope a my future kid asks me this when they are five. \n\n\"Social Darwinism is a opinion that bad people and bullies have about how the world should be. They think helping people is bad because they don't like people who need help. The truth is we all need help and we are all in this together.\"",
"Social Darwinism is best explained to a 5 year old by \nJohn Kenneth Galbraith\n\"The modern conservative (social darwinism) is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness.”\n ",
"The social Darwinism I've studied is basically \"survival of the fittest\" of the social world. Poor people aren't working hard enough to succeed type of thing. There are two conflicting ideologies concerning this matter. One type of ideology is the capitalist, \"hard work pays off\" type of ideals. I once played WoW, so I'll explain it in terms of that. The more you complete quests and complete dungeons/raids, the more you succeed in the game (more gold, better gear). This can be true in our real social world (more work, more money/status) , BUT it is not always the case. Studying Social Sciences as I have, a bigger issue is at hand here. Back to WoW. Imagine doing those things mentioned above, but for some reason your specific race or class doesn't benefit as much from the tasks as other players and this was done by the developers with their own special interests in mind. All of sudden your Orc Warrior is at half the potential of a Human Warlock and you do a battlegrounds match. The Orc would surely lose and it's not because the Orc hasn't worked hard, just that there was no oppurtunity because the developers favor the alliance Human players. Same in the real world (unfortunately). Race / status / education all come into play in society and those that have higher status are designing the rules. That's my two cents. (kinda think I just wanted to talk about WoW)...",
"In regular Darwinism, the fittest organism prospers. Social Darwinism was a way to justify imperialist expansion *scientifically*...if you could take over another culture, you should, and you were right to do so because you're superior and they're not (if that wasn't the case, you wouldn't have been able to beat them in the first place).\n\nObviously kind of a prickish idea. On the other hand, we've now swung so far in the direction of cultural relativism that there is no way to call out a shitty culture for being shitty.\n\n",
"As Nietzsche said, 'like ants, the weak are innumerable so they always overcome the strong' but by fittest Darwin meant most able to adapt. Trust me, when the S#*% hits the fan the rich, with their robot pool cleaners and weed wacker adapters for edging things pristine, are not going to be the most adaptable.",
"Using Darwin's The Origin of Species to \"prove\" that people of minorities were biologically and mentally inferior to white people. The Eugenics movement sprang from this idea and used false psuedoscientific experiments to prove this. The findings from these studies were totally skewed, and the experiments almost never followed the scientific method.",
"I was once accused of being a social Darwinist. The debate in class was 'are pharmaceutical companies guilty of genocide in because they won't give free antiretroviral medication to the people in Africa who have AIDS/HIV?\" \n\nAs the discussion fumbled on for about 30 minutes, the comments from the other students reflected the idea that the antiretroviral medication was the \"cure\" for AIDS/HIV. I was bothered by this, because while it may help the person's quality of life it doesn't magically \"cure\" AIDS/HIV (the students in charge of the presentation did eventually cover this point, but it was the final slide in the powerpoint presentation). I raised my hand and pointed out that it wasn't possible to assume that a person with AIDS could go on to lead a 'perfectly normal life like they didn't have it' after taking the antiretrovirals. They are still going to be at risk for transferring it to their children and sexual partners and that taking the medicine isn't the end all solution to the problem. \n\nEveryone in the class gasped and I was accused of social Darwinism. I'm still not sure how it's considered social Darwinism, since AIDS/HIV is a HUMAN problem, and the virus doesn't care about race/gender/social-status/rank/income/which landmass you live on.\n\nEither way, no one talked to me for the rest of the class.",
"I think that, to understand Social Darwinism, you need to understand the development of \"race\". \n\nInterestingly, the idea of \"racism\" itself as we know it doesn't develop until fairly recently. Early human societies did not have a concept of \"race' like we do today, but rather judged you based on the group you belonged to and your traditions and customs. Yea, early Chinese did not care for the blonde haired barbarians to the west, but it was not their \"race\" that bothered them as much as the fact that they did not belong to their group.\n\nLikewise, slavery was, on the whole, not based on race as much as it was based on one group of powerful people subjugating another, and a particularly talented or skilled member of the subjugated group had the possibility of being accepted into the group doing the subjugating. \n\nWe sort of see this switch most noticeably in the Spanish treatment of the indigenous Americans. They were treated as slaves and subservient after Spanish conquest but, once they began converting to Christianity and developing Spanish customs, the Spanish throne began outlawing the slavery of any Natives who had become \"Spanish\". \n\nBut, by the time the Portuguese and Spanish begin bringing in African slaves, the idea of racial disparity and, with it, that some \"races\" were naturally and irrecoverably inferior to others had taken hold. \n\nSo, for the most part, the idea of \"race\" as a construct served to advance European empire and was a convenient excuse for what gave, say, the Portuguese the authority to sail into the Indian Ocean and take over trade routes that had flourished since Roman times.\n\nSo, when Darwin came along in the mid 1800's, his ideas of divergent evolution and the idea that nature \"selects\" the strongest got co-opted by the groups that had been practicing racism since the mid-1500's, and used it as \"scientific evidence\" for what they had been doing. Phrenology, or the \"science\" of discovering someones personality traits through their skull shape, had hit its peak 50 years before *Origins*.\n\nSo, to answer the question, Social Darwinism is essentially racism (although sometimes applied to class as opposed to race), where a stronger group sees itself as inherently superior based on its ancestry and acts to exploit other, inferior groups. The term itself is simply a mid-19th century attempt to take a horrendous practice and put a scientific spin on it. "
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2wauni | if hackers were able to use inside knowledge of bank systems to steal $1 billion over time, how would they eventually have cashed in? | In this [reddit front page article](_URL_0_) recently posted, thieves managed to make off with some serious dough by infiltrating bank systems and using them to their advantage.
I get that measures, in particular amounts stolen under certain thresholds allowed the hackers to go undetected for a long time, but once detected how can they get away with the theft?
The article does mention that a lot of theft had to do with them making ATMs spit out cash at certain times that they presumably collected and I can see this being harder to trace but at least some of it sounds like it's described as having been transferred in to accounts.
How does the scam work if you have to put the money in to accounts which are presumably tied to people. Even if they don't notice for a long time and you spend it all surely there'd now be an identity they could use to try and track you down. They would have to have set up a lot of these too. They say something in the article about fake accounts, but if that detail is now known that accounts had been created fraudulently, then presumably they've figured out which ones they were and seized the funds. If the money was transferred from that account to any other account whatsoever that would leave a trail wouldn't it? Like you couldn't just transfer it all to your personal account with your name and address that you used to get it.
I know this sounds really naive but I don't actually see how the mechanism works for getting your hands on the money once you've successfully stolen it. Even the ATM cash presumably would be traceable because I'm guessing there's a log of what notes the machine has dispensed and that those notes are uniquely identifiable, I guess you could launder it though. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2wauni/eli5_if_hackers_were_able_to_use_inside_knowledge/ | {
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"Pulling the cash out of ATMs would be hugely time consuming and increase the risk of getting caught. The better approach (and the one they're most likely to use) is to keep bouncing the money around the globe via wire transfers, ideally to countries with very strict banking privacy laws (Switzerland, Caymans, Singapore, etc). From there, disperse the money into smaller transfers to companies that can be used to launder the money. Online retailers of luxury items would be a good choice, although I'm sure there are plenty more options. ",
"ATMs do not, to my knowledge, keep a log of the unique identifiers associated with individual bills. It's possible, with modern technology to scan each bill, but it's so easy to launder the money that it wouldn't be worth the expense. \n\nFirst, and most important, they limited themselves to, I believe it was no more than ten million dollars from each institution. Believe it or not, that is actually a pretty small amount of funds to move unnoticed. As someone else mentioned, you can easily move funds from one bank to another and then another until all trace has been removed and the money has just disappeared. \n\nThe answer here is that it's nearly impossible for you to walk into a bank and steal ten million dollars today but if you have the time, patience and expertise to spend stealing small amounts over long periods of time, it's surprisingly easy. \n\nYou'd be surprised the ways that people have learned to take advantage of banks over the years that were far more successful than you would think. ",
"Theres a really good blackhat video on youtube about stealing from ATM's It's quite interesting how he did it, and also relatively untraceable. ",
"[From the Kaspersky report](_URL_0_), they've moved the money between banks, added some money on people's accounts, then remotely dispensed it from these accounts on various ATMs around the world, where it'd be picked up.",
"While the ATMs spitting out dollar bills is the cool Hollywood part of the story, Cash is much less useful to criminals than electronic money. \n\nEven if you know where the money started out at, the longer the money laundering chain becomes and the more jurisdictions it crosses and layers of transactions it gets from the source, it becomes virtually impossible to trace. There's so much money flowing around the global economy just as part of its normal functioning that you can hide in the volume.\n\nCome check out /r/MoneyLaundering if you're interested!"
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4r2tqj | why is it more damaging to binge drink than to regularly drink in small portions the same amount of alcohol? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4r2tqj/eli5_why_is_it_more_damaging_to_binge_drink_than/ | {
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"So your liver is your filter of your body.\n\nTakes care of the toxins and regulates the body.\n\nWhen the liver has too much alcohol to handle, normal liver function may be interrupted. Chemical imbalance!\n\nIf the liver is required to detoxify alcohol all the time liver cells may be destroyed or altered! Fat deposits (yuck), inflammation (boo), or permanent scarring (not good).\n\nIf you dump a whole bunch in at once- liver is overwhelmed. Small amounts are dealt with more efficiently by the filter.\n\nIn general though, don't poison your body too often. Keep the liver running well!"
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7ozvdh | how do hashing functions avoid collisions? | If you have a 256 bit hash with 2^256 possibilities and run every file ever created, would there be collisions?
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7ozvdh/eli5_how_do_hashing_functions_avoid_collisions/ | {
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"Yes! Every Hashing function will have collisions. Each function also chooses how to deal with collisions. With a hash space like 2^256, you should be able to minimize collisions as I believe that number is bigger than the number of molecules thought to be in the universe (fact check that). Huge hash spaces help to minimize collisions, and good techniques for management can help to prevent clustering and further collisions.",
"By being well designed. A hashing function should have a good \"spread\", similar values should have dissimilar hashes, and hash values should be well distributed throughout the range without any clustering.\n\n > If you have a 256 bit hash with 2^256 possibilities and run every file ever created, would there be collisions?\n\nUnless it included files deliberately constructed to create collisions, probably not. 2^256 is one of those \"all the atoms in the universe\" type numbers, and greatly exceeds the total number of files that have ever existed.\n\nFor digital signatures, if the hash is secure, it is usually ok to ignore the possibility of collisions. For a hashing table, where the range is a lot smaller, you are going to want to have some means to handle collisions.",
"All hashes have an infinite number of collisions. What you're doing is mapping an infinite set into a finite space, so they're inevitable. An example of a really naive hash over a tiny space would be taking the remainder of division by 10 - all your hashes will map to a space between 0-9, inclusive, no matter how big or small, positive or negative an integer you use.\n\nIdeally, a robust hash is going to have a good distribution, but you also have to consider the nature of your inputs; hypothetically, the nature of a set of inputs may happen to have lots of collisions with a given hash - the problem isn't necessarily the hash itself, it's the hash chosen for those inputs. Using the above example, if your inputs are all even, you'll get twice as many collisions, because you're effectively halving the hash space. If all your inputs are a multiple of 10, then all your hashes will be 0. As you can imagine, a more sophisticated hash is intended to mitigate this problem, but there's no reason it can't happen.\n\nYou can change the algorithm, you can increase your hash space, but given a large enough input set, collisions are inevitable. If your input set were infinite, then hashes would be useless, as all inputs would collide."
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zepld | Were there ever revolutions without political killings? Unlike Cuba, Soviet Russia and I'm sure others? | I'm asking because in my country, Portugal, after the 25 of April revolution in 1975 there was almost no blood spilled. There were some fighting at the time of the taking of the Dictator's HQ and there were some political killings in the 80s by a terrorist group. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/zepld/were_there_ever_revolutions_without_political/ | {
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"I think [this](_URL_0_) counts. There's actually a whole documentary about it as well.",
"Most of the Soviet Union's puppet states fell with little or no bloodshed. And the coup that put the end to the Soviet Union itself was also a fairly tame affair. Romania and Yugoslavia excepted, and some fighting in the Baltic states and Caucasus. \n\nNapoleon III was elected president of France in 1848 - he mounted a coup in 1851 before taking power as Emperor that seized control of all of France and its empire with only a few hundred deaths. Not small potatoes but not terrible given the coup's scale. \n\nBrazil was declared a republic after a bloodless coup, although there were several small monarchist rebellions after the coup ended.",
"The Czech revolution is known as \"The Velvet Revolution\" because of how peaceful it was."
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1jypvt | why do the graphics improve so much from super mario bros to smb 2/doki doki panic to smb 3? | They were all on the NES/Famicom and I have no idea why they went from barely looking like a person to actually looking like... Mario. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1jypvt/eli5why_do_the_graphics_improve_so_much_from/ | {
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"The NES actually has a surprisingly unique development model. Basically, the cartridges provide their own computing power. The NES by itself is a pretty crappy system, even for its time; it only has 2KB of internal RAM (yes, that's about one 512th of one 4096th of the average amount of RAM on most computers today), the GPU can only display eight different sprites (AKA \"pictures\") on the same TV scanline (any horizontal line) at a time, etc. But because cartridges plug directly into the system, they can sort of \"upgrade\" it by providing their own RAM and things called mappers. Of course, they can't do everything like upgrade the CPU speed; they can only enhance some aspects of games, which is why eventually everybody migrated to the SNES. \n\nBasically, the 6502 CPU in the NES can only address 64KB of memory at any time, and some of that has to go to internal graphics memory and RAM, meaning that on the first ever cartridge made for the NES, they only had very little space to store all of the game code and graphics. Later on though, cartridges got better and these things called \"mappers\" were invented, which basically automatically swap out certain parts of addressable memory with memory on the cart, leading to a theoretically infinite amount of memory, because new memory could be swapped in. There are different methods of swapping that each have their own advantages, and that's why there are different mappers used in different carts today. The most popular mappers, MMC, have gone through five revisions: MMC1, MMC2, MMC3, etc, and each one got successively faster at swapping memory and making the NES faster.\n\nSo early on, games had to deal with limited memory, but as carts got better and had better mappers, better games could be made. This led the NES to have a very long lifespan, because cartridges were always improving. Unfortunately the same concept doesn't apply to most modern consoles because games are only a disc (or, sometimes, only a download) and nothing more."
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3fg9vh | why do cigars smell good, but cigarettes smell horrible? | Title. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3fg9vh/eli5_why_do_cigars_smell_good_but_cigarettes/ | {
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"Cigars and pipe tobacco use real, raw tobacco (of course, dried and all the usual stuff you hear about them doing in colonial times). Cigarettes are ground, processed, and treated with chemicals to make them burn longer and have a taste. Plus, cigars are wrapped in tobacco leaves while cigarettes are just wrapped in paper.",
"Many people (although not me personally) find the smell of cigars to be even more offensive than cigarettes. It is also a much more pungent and powerful smell. \n\nAs to previous replies, I used to smoke American Spirits which are (supposedly) pure tobacco and nothing else. Still smelled like any other cigarette."
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b8rju1 | why do freud's theories keep on being validated even if there is no scientific evidence about their reality? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b8rju1/eli5_why_do_freuds_theories_keep_on_being/ | {
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"You can't prove Freud's theories right or wrong because they don't make falsifiable claims. As such, they are not science and should not be regarded as such.\n\nHowever, social sciences are rife with these sorts of dogmas. Remember, at one point people believed disease was carried by 'bad vapors'. Social sciences are much newer, so they still have the detritus of their pre-scientific past to deal with. There are still people active in academia who built their career on Freud (and other early psychologists like Jung) and aren't really part of the conversation unless they insist that their life's work is valid.\n\nIn terms of \"brilliant and beautiful\", it might help to recognize that you can take almost any arbitrary pile of features and discover correlations between them."
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91znvw | Are there other deep water areas of the ocean that we know camparitively far less about due to all the attention given to the Mariana Trench? | In general it just seems that the ocean floor is so vast and we’ve given so much attention to this little area, for all the talk about it’s mystery I wonder if we actually know more about it than we do the rest of the sea floor. I’m wondering how our knowledge of the Mariana Trench compares with the rest of the ocean and if there are other big, but not as big trenches that we haven’t explored nearly as much.
*comparitively, sorry | askscience | https://www.reddit.com/r/askscience/comments/91znvw/are_there_other_deep_water_areas_of_the_ocean/ | {
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"We know about [more deep places](_URL_2_), e.g. [Puerto-Rico Trench](_URL_3_) or [Tonga Trench](_URL_1_), but I would say we don't really know much about Mariana Trench or other deep sea trenches. It's just it being known as the deepest point, so it has more attention. But less deep areas are easier to explore and study due to not so high pressure.\n\n[NOAA says we still didn't explore more than 80 % of the ocean floor.](_URL_0_) It's just those extreme areas like deep sea trenches are easier to spot. There is only so much we can learn by using satellite altimetry, sonar, lidar or high resolution orthoimagery and submarines are expensive. It's true we know more about surface of the Mars than of our own ocean floor."
]
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1pr2ou | why is it easier to open twisty caps by holding cloth between your fingers and the cap? | I mean, I feel the difference, but I don't understand the physics behind it. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1pr2ou/eli5_why_is_it_easier_to_open_twisty_caps_by/ | {
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"Friction. I wish I had pictures of a zoomed in surface...,it makes it easier to explain the traction. But basically...the more bum bumps /ridges, the more traction. Hands are oily and this oil coats some of the bumps lowering the grip of hands to cap. Covering it with a cloth keeps the oily hands off allowing better grip and friction ."
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|
3qady9 | why doesn't the cost in octane rating change with gas price changes? | My car requires 91+ octane rated gas. Within the past 2 years I have noticed that the price difference between fuel grades jumped from 10c to 15c. Just this week it started to become 20c difference! Even though gas has gone way down to $2.04 (unleaded) premium is $2.44 where I live. I read that octane is made out of the same crude oil, are they just trying to screw the customers? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3qady9/eli5_why_doesnt_the_cost_in_octane_rating_change/ | {
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"This is most likely due to the oil you buy takes time to refine, and the oil retailer bought the expensive oil a long time ago and stored it and slowly selling the remaining stock and wont want to make a loss. thus the price of crude oil is elastic while the price of retail oil is rather inelastic. ",
"It might relate to where you live. There are some pretty dumb legal requirements in California, for instance.\n\nAlso, the amount that companies charge is not legally required to make sense.\n\nBeyond that, perhaps there are reasons!"
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2v4aa2 | How can you tell the difference between Alzheimer's and Lewy Body Dementia? | My grandfather died of Lewy Body Dementia, and for the longest time we thought it was Alzheimers. The doctor said it was most likely Lewy Body Dementia, but he matched almost all the symptoms for Alzheimer's. Can someone please clarify the line between what is Alzheimer's and what is Lewy Body Dementia? | askscience | http://www.reddit.com/r/askscience/comments/2v4aa2/how_can_you_tell_the_difference_between/ | {
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"Sorry for your loss. \n\nThe differences between Alzheimer's and LBD are primarily clinical and symptom-based. Alzheimer's tend to be more insidious with the first clinical symptom failure of recall and memory-based. Lewy Body Dementia usually show up with more loss of visual-spatial and executive functions. (ie. inability to plan ahead with tests such as Clock Drawing)\n\nAlso, post-mortem studies in LBD patients will often find proteins called Alpha-Synuclein in the brain, which is also found patient's with Parkinson's Disease. This puts Lewy Body Dementia in a category called Synucleinopathies and patient's will often exhibit parkinsonian features. (Cogwheel rigidity, bradykinesia...etc etc) In Alzheimer's Disease, the principle pathology found in the brain are neurofibrillary tangles (tau proteins) and neural plaques (Amyloids). "
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3il4k5 | I am looking for good sources on the history of (USA) Worker's Unions | I am currently researching Unions and Organized labor for an independent study class. While I am sure simple Google searches can turn up a number of different titles, I am very wary of bias. Would you kindly recommend some books, papers, or journals dealing with Organized Labor in the United States of America? Thank you. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3il4k5/i_am_looking_for_good_sources_on_the_history_of/ | {
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"Check out the work of David Roediger. Also Philip Foner's work is classic. More recent is Philip Dray. What aspects are you looking at? ",
"Are you looking for works that are an overview of the history of Unions which analyses sources to paint a picture, or would you like primary sources - articles etc. written by people involved in the Union movement at periods in history?",
"Here's a handful that have made it into my notes, coming at the topic from a more socio-cultural and political-economy angle (I'm interested in workers as consumers):\n\nLizabeth Cohen, *Making a New Deal : Industrial Workers in Chicago, 1919-1939*, Second Edition (Cambridge [England]; New York: Cambridge University Press, 2008).\n\nJefferson Cowie, *Stayin’ Alive: The 1970s and the Last Days of the Working Class* (New York: New Press, 2010).\n\nNelson Lichtenstein, *Labor’s War at Home: The CIO in World War II* (Cambridge [Cambridgeshire]; New York: Cambridge University Press, 1982)\n\n George Lipsitz, *Rainbow at Midnight: Labor and Culture in the 1940s* (Urbana: University of Illinois Press, 1994).\n\nRoy Rosenzweig, *Eight Hours for What We Will: Workers and Leisure in an Industrial City, 1870-1920* (Cambridge; New York: Cambridge University Press, 1983).\n\nNan Enstad, *Ladies of Labor, Girls of Adventure: Working Women, Popular Culture, and Labor Politics at the Turn of the Twentieth Century* (New York: Columbia University Press, 1999).\n\nLawrence B Glickman, *A Living Wage: American Workers and the Making of Consumer Society* (Ithaca, N.Y.: Cornell University Press, 1997).\n\nI'll do a quick search and see if I can find a 'state of the field' essay for labor studies that's fairly recent and might guide you toward more cannonical works within that subfield of history itself. (Which is kinda dying in favor of more integrative histories of capitalism, btw.)\n\nIMMEDIATE EDIT: also, check out the stuff written by Joseph McCartin - incl. his 2013 *Collision Course* which is very under-grad and public reader friendly. His interpretation of labor history runs counter to Cowie's hypotheses in several interesting ways, so there's some nice counter-point to think with there . . . "
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rylzk | Could a place like Black Mesa (from Half-Life) really exist? | Given the resources that the Earth had in the year 1998, and assuming that Black Mesa had already been around a few years before that already, would it actually be humanly possible for a facility like Black Mesa to really exist? I'm meaning this question to be about size, not experiments. If so, is there already a place like this in existence? | askscience | http://www.reddit.com/r/askscience/comments/rylzk/could_a_place_like_black_mesa_from_halflife/ | {
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"US Government National Labs feel pretty close. They're not quite that huge but the number of just off the wall awesome experiments being conducted make them feel a bit like either Black Mesa or Aperture type of things could be going on. \nLos Alamos National Lab has lots of secret stuff going on, many things concerning the US nuclear weapons program.\nI imagine the the large hadron collider would feel a bit like Black Mesa, aside from being in different terrain. It is freakin huge... I've never been there but its sheer scale is breathtaking."
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2oa1tr | what is actually happening when i'm warming my car in the winter? | Does warming the car make any difference in terms of functioning? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2oa1tr/eli5_what_is_actually_happening_when_im_warming/ | {
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"You're trading comfort for efficiency and reduced wear. At idle the engine takes considerably longer to warm up to normal operating temperatures; extending the time it's running at ideal temps. Some newer diesel engines are actually so efficient that idling when it's cold out will never get them up to normal operating temps. This increases wear slightly and of course wastes gas. Unless it gets absurdly cold - in which case you should install and use a block heater - you should let your car idle for no more than a minute before driving. Until the engine reaches normal temps (roughly 10-15 minutes regardless of what the gauge says since most are buffered these days) simply keep the revs lower than about 3,000 rpm and don't give it excessive throttle.",
"The fluids in your car are more viscous when cold and make your engine work harder until warmed up."
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2rzgfk | Jewish Wine | In an episode if Frasier, Frasier Crane is dating a Jewish woman and is suddenly forced to meet them. While his girlfriend at the time didn't create about him not being Jewish, her family would so he pretended to be Jewish, forcing him to take down Christmas decorations and serve Jewish foods. However he didn't have Jewish wine, so his brother poured a glassof regular wine and added a heaping teaspoon of sugar to it.
So, I was wondering, why is Jewish wine different than regular wine and was there a historical reason to this? Was wine once sweeter as well? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2rzgfk/jewish_wine/ | {
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"It actually doesn't have much of a historical reason. The most popular kosher wine in the US is Manischewitz wine, and they add sugar to their already-sweet wine. Frasier is playing off this stereotype. But kosher wine need not be sweet; I'll let someone else answer about historic Jewish wine. ",
"This exists for a particular historic time and place. Traditionally, there was nothing particularly sweet about Jewish wine. However, in order to have kosher wine, there are a number of procedures that need to be followed, resulting in Jews being pretty much the only people who grow kosher wine. As Jews emigrated to the United States, the population was predominantly found in New York, and Jewish businesses, including the kosher food industry, centered around there. However, the only grape that would grow in the New York area, especially before more modern cultivation techniques, is Concord grapes, which are rather sweet and don't have the best flavor. But that was what available. This is the main grape used by everyone to make grape juice and grape jelly, due to its sweetness. So the end result was that kosher wine in the New York area, and then across all of the US, came to be made with sweet Concord grapes, and then a stereotype formed around Jewish wine being sweet, in the 20th century. But there's no history of it nor any Jewish reason why it must be so. I've lived in France, and there are kosher wines of all varieties there. They scorn the poor quality sweet kosher wine that Manischewitz makes. It certainly doesn't need to be true any more, but people have grown used to it and it's become a tradition. There's no huge Jewish tradition of drinking or interest in alcoholic beverages, so there's never been any huge Jewish movement to have better wine--if you're not too religious, you'll drink any wine that interests you and don't have to concern yourself with it being kosher. If you are religious, then you'll only drink kosher wine and you're not going to spend too much time fretting over the secular practice of drinking wine as a leisure activity."
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1pyn4l | Is the arrangement of our small intestines fairly similar across humans, or unique to each person like a fingerprint? | I've always imagined a tangled mess. Are things in our gut a bit more organized than I've pictured? | askscience | http://www.reddit.com/r/askscience/comments/1pyn4l/is_the_arrangement_of_our_small_intestines_fairly/ | {
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"Your intestines (specifically small intestine) are attached to the back of your abdominal cavity by a tissue structure called the \"mesentery\". Basically this is a sheath that surrounds the guts and allows them to move pretty freely around the abdominopelvic cavity. An interesting example of this freedom of movement is when you have surgeries on certain structures, the surgeon will just move your intestines to the side and shove them back roughly into position when they're done. Then the intestines will rearrange themselves back to their initial position (which it's moderately uncomfortable to say the least!). So basically, the points of attachment for the intestines are the same for everyone, but there is some room for variation. \n\nTL;DR- guts are attached in the same way for everyone, but have freedom of movement inside the body cavity, so there's some room for variation ",
"I haven't seen enough intestinal radiographs to be sure, but I know these three facts:\n\n\n1.) The small intestines are anchored at two ends: the stomach- > duodenum proximally, and the ileum- > cecum/ascending large intestines distally. The location of these two limits are very consistent across people (as consistent as we can get in people with different abdomen and organ sizes).\n\n2.) The small intestines undergo a conserved rotation while we're an embryo. Before our abdominal muscles form a wall, our intestines come through with our umbilical cord, rotate 270 degrees (which gives our large intestines the characteristic bend), and then go back into our abdomen. This happens across many species. This is related to the small intestines being anchored at two ends.\n\n3.) Perhaps most relevantly, the small intestines are only anchored to the back by a ribbon of fat/connective tissue/blood vessel called the mesentery. It runs along the entire length of the intestines, and originates from the superior mesenteric artery. It is basically like a fold-up fan, and doesn't have much structure. From what I've seen, there's a lot of anatomical variation in even how the smaller branches of the superior mesenteric artery form. Thus, **I would think the layout of the small intestines have large variation, too**. \n\n\nAlso, given there aren't many ways for intestines to be solidly attached, your guts can roll around all the time. There wouldn't be a distinct inborn pattern to the folding due to the fluidity of the intestines. However, the branching of the arteries (e.g. superior mesenteric artery) are unique to individuals.",
"Surgeon here. They are the same. Variations of the position and length of segments such as the appendix vary only slightly. The general \"mess\" is organized. This is due to the mesentary which supplies the vascular and nervous input to the organ. This also gives it anchoring points. The small bowel can be considered as a line from the upper left to the lower right side of the abdomen. This line represents the mesenteric insertion. The mesentary is pliable and the small intestine are suspended with wiggle room to traverse perpendicular to the mesenteric line. Think sinusoidal curve around an axis. The mobility can make it appear disorganized but it's redundant nature with manipulating a large organ in a confined space is the reason for the misleading surgical descriptions. At the bottom right, the large intestine (colon) begins. This courses up towards the ribs, across to the left side, down, and back to the anus. ",
"For your consideration, a dissection of the gastrointestinal tract, abdominal organs, and an examination of abdominal blood vessels: _URL_0_\n\nObviously NSFW and not for everyone. But damn interesting.",
"Sounds like you got your answer for intestines, but if you're looking for unique tubes, look for veins. While the general structures are similar, each person has a slightly different vein system because it's formed from a bunch of blood vessels and narrowed down to the ones with the lowest resistance.",
"The intestines themselves probably aren't particularly uniquely arranged, and their vascular supply follows a general paradigm, however, the terminal branches of the vascularity divide unpredictably like branches of a tree and if visualized might be significantly specific like a fingerprint. ",
"There's some degree of variation, but not like a fingerprint. What I have found to be more unique between individuals in a meaningful, potentially identifiably way, are the branching arrangements of abdominal vasculature and the bile ducts. These structures also lend themselves to visualization more readily.\n\nSource: I make surgery videos for a living, and reconstruct patient anatomy from CT scans for each video.",
"I perform barium folowthrough studies on a regular basis to image the small intestine. The other comments are mostly theoretical.\n\nAlthough the small intestine is attached in a fairly similar way, it is very dynamic and it's position and appearance are different from one minute to the next depending on your physique, what you have eaten and what you are doing. This becomes more complex again if you have any medical problems related to the small intestine, or a history of previous bowel surgery.\n\nTL; DR everyone is different and it changes from minute to minute.\n\nsee here:\n\n_URL_0_"
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ag3exj | How did Project MKUltra maintain its secrecy so effectively for twenty years? Across 80 reported institutions, how was there not even one whistle-blower? What eventually compelled the government to go public in 1975? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/ag3exj/how_did_project_mkultra_maintain_its_secrecy_so/ | {
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"Here's an interesting piece of history that helps us understand: \n\nIt was a different time, people going for \"weird psychiatric cures\" at leading institutions in their city or country would have thought less about the brutal and suspect methods. \n\n**Exhibit A.** \n\nMontreal Neurological Institute / McGill and the Peter Allan Institute. In the 1900s, Montreal, Canada was one of the Mecca's in neuroscience and still is. There was a guy named [Dr. Ewan Cameron](_URL_0_) who at points in his life was the head of the American Psychiatric Association (1952–1953), Canadian Psychiatric Association (1958–1959), American Psychopathological Association (1963), Society of Biological Psychiatry (1965) and World Psychiatric Association (1961–1966). He had a theory and afaik was the one who came up with the \"Depatterning\" idea of giving drugs then subjecting people to images with their eyelids kept open, think Clockword Orange and the stereotypes of that kind of \"mind control\" or \"mind wiping\". \n\nHis research was funded by the U.S. government. While he knew his research was being funded by a foreign government, I'm not sure if he knew it was being funded by CIA/more secretive groups. Regardless, he was doing some heinous research with the money.\n\nPeople would go for depatterning at his institution of the neurological institute, be completely messed up, substance induced or activate a permanent psychosis, then they would end up at the hospital, then to Mcgill, then hospital, then to the Peter Allan institute. There was little cross-talk between institutions even in the same city and people would be shunted from one to the next in the worst cases. This is how it went undetected. Otherwise, people probably thought \"o they didn't get a lobotomy, they must be crazy though, wonder how they got this way, must be in their blood\".\n\nEven Donald Hebb, of \"fires together, wires together\" fame was funded by the same foreign bodies but he claims he didn't know how insidious the money was, and we believed him. That's another story and he is a well loved and important figure in neuroscience. Ewan Cameron, however, who's heard of him anymore? He permanently injured and indirectly killed many with his depatterning. \n\n------\n**All in all,** the CIA funded research all over the world, it was decentralized and they looked for researchers with credentials and no scruples to conduct the kind of research we know they did. It also took ignorance, willful or otherwise, a different time and standards of care/research subjects, as well as no one connecting the dots. Think of it this way, you are a scientist with existing research, a granting body promises money in return for your research, you take the money in return for giving your results to them. Maybe it's only 1/4 of the research your lab does anyway, you take the money from this non-scientific body and your department either doesn't know or doesn't think it's all that bad or out of the ordinary. \n\n\n\nNot familiar with how the dots were connected or by whom but I hope this gives a picture of the actual context for how things went down.\n\n- editing to add that also, because of the lack of what we consider modern scientific rigor, not only were Ewan Cameron's findings unethical, the research methods were crap. They did not work to \"depattern\" or \"wipe a mind\" like he claimed. He just made a whole lot of psychosis and we learned next to nothing from all that suffering. "
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fqblvr | what changes happen to make "adult foods" (e.g. asparagus) taste good later in life, but not when you're a kid? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fqblvr/eli5_what_changes_happen_to_make_adult_foods_eg/ | {
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"Kids have increased sensitivity to bitter foods. Veggies taste bitter to kids. Adults have reduced sensitivity to bitter foods. The veggies will taste better to them.",
"Tastebuds die as you grow older. It’s not that they “taste better” so much as adults no longer have and many “that tastes awful” buds.",
"The answer is a complex combination of physiology and psychology. As a couple users have pointed out taste buds diminish in time (although this doesn't begin until midlife for most adults.) Additionally, evidence indicates that children may be able to detect bitter compounds better than adults. However, neither of these is accurate alone, as taste *preference* is largely psychological^[1](_URL_1_).\n\nPeople *learn* to like the items they did not like as a child. The only thing changing is your own mind. Exposure to a flavor and the context in which it was experienced provide a major influence as to the like or dislike of that flavor. As you continue to be exposed, you develop an appreciation (or confirm your dislike as the case may be.) For example, perhaps you're hit by an illness following the eating of a specific food; you may be significantly less likely to enjoy or try that food again as a result (a common side-effect of food toxicity.)\n\nInitial food preferences can be thought of as being the physical side of this all, and are based on our sensitivity to various tastes and chemicals. Humans tend to prioritize high energy foods so things high in fats tends to taste better universally^[2](_URL_2_) . When it comes to vegetables though, it's the bitter chemicals that stand out the most (edit: and is one reason why kids may not like them - because bitter is a taste instinctively linked to poison/toxic substances^[3](_URL_3_) .) The likely explanation for this is evolutionary pressure^[4](_URL_0_) which shaped our tastes to accommodate the region in which we lived. For instance, populations in malaria-infested areas are more likely to have genes which make them less sensitive to bitter tastes, in particular cyanide. There's speculation that cyanide - when consumed in low levels - may fight malarial parasites.\n\nLike you were actually five explanation: Nothing *really* changes. We just learn to enjoy them over time.",
"For me I didn't like alot of things as a kid. Never really gave them a chance. But when I get real high and hungry I'll try anything. Some things that I realized are dank that I never ate as a kid: cheese(other than American), broccoli, asparagus, sushi, cabbage (any variety really), yogurt, avocado, sour cream, and I'm sure there's more.\n\nSome things I still can't do: Hawaiian pizza, squash, pumpkin pie, plain raw tomato, cottage cheese",
"Part of it is child rearing practices. In cultures where bitter foods are what’s on the menu no matter what, you don’t get kids who are picky about it like most American children. In child development it takes 10-20 “tries” for a kid to learn a new flavor. Many first world parents will see a baby make a squinchy face after trying creamed spinach (for example) for the first time, decide she doesn’t “like it”, and won’t offer it again. This is one reason why some children become extremely resistant or even traumatized about certain foods. A lot of the child psychology reality television on Youtube is about “picky eaters” and it always comes down to parents just not offering enough variety for children to learn new flavors. \n\nSome kids, especially on the spectrum, may have physiological sensitivities however and aren’t just normal-picky. This is hard to diagnose, however.",
"I learned how to actually cook vegis. \n\nMy mom steams EVERYTHING.\n\nRoast your vegis, pan sear them and for the love of God buy them fresh. \n\nI can't stomach canned spinach, but I love fresh spinach."
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"https://www.apa.org/research/action/speaking-of-psychology/foods-we-like",
"https://www.ncbi.nlm.nih.gov/pubmed/9216570",
"https://www.eurekalert.org/pub_releases/2006-09/mcsc-bti091206.php"
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2vln2j | why do sugarcane plants produce so much sugar? do they need sugar or is it a by-product? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2vln2j/eli5_why_do_sugarcane_plants_produce_so_much/ | {
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"Plants need sugar for energy. Sugar is no different than other plants in that. Some just produce a lot, or at least easily extractable like maple syrup or beets or fruits (slightly different sugar) "
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p1dvb | Is it true that anyone who grew up in the walkman generation and beyond will most likely need hearing aids when they are old? | I just read a talk by a famous speaker who casually mentioned that because he grew up in the walkman generation that he will need hearing aids when he is "decrepit and old". Is this true? Does the fact that I own and frequently use my phone and ipod to listen to music mean I will need hearing aids in 40 or 50 years? | askscience | http://www.reddit.com/r/askscience/comments/p1dvb/is_it_true_that_anyone_who_grew_up_in_the_walkman/ | {
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"Hearing loss? Maybe. Full blown deafness? Unlikely. This isn't a particularly new phenomenon, I found papers going back to the 60s on whether the kids are going to damage their ears with loud music, including [this](_URL_0_) adorable paper from 1968. Opening line: \"Rock and roll music is generally considered to be very loud, particularly by those over 25 years of age. Anyway, long story short, they found some hearing loss in 5% of their sample, but hardly widespread deafness\n\nBut now it's 2012, and we have earbuds, and many people listen to them at high volume all day long. There's no question that prolonged loud noise can cause hearing loss. Studies have suggested that music players are at least associated with hearing loss [source](_URL_2_). However, it's not entirely clear whether we're losing our hearing faster than previous generations - in fact, there's evidence that current generations have better hearing [source](_URL_1_).\n\nSo it's a bit of a gray area. Worse yet, mp3 players have only been around for a few years, if the youth of the world have accelerated hearing loss, it's too early to tell. At any rate, we're talking about hearing loss and tinnitus here, not full-blown deafness. You should probably listen to your music at a reasonable volume, but shouldn't worry too much about a world of deaf 50 year-olds people yelling at each other."
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"http://www.jborak.com/publications/docs/Slade-Rabinowitz.pdf",
"http://www.noiseandhealth.org/article.asp?issn=1463-1741;year=2009;volume=11;issue=44;spage=132;epage=140;aulast=Kumar"
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b0d6vm | why are some boats pointy on both ends, while other boats are pointy in the front and flat in the back? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b0d6vm/eli5why_are_some_boats_pointy_on_both_ends_while/ | {
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"Vessels move through the water more efficiently when they are streamlined (both ends pointy) because the flat stern (back end) creates a void as the boat moves which pulls it backwards a little. If you want to mount a motor on the back of your boat you're gonna need to make the stern straight so you can mount it in a way that is structurally sound.\n\nEDIT: There are many exceptions to this. First, they make trolling motors that you can strap onto the side of a canoe. This works because a trolling motor isn't very powerful and the shear forces this creates aren't enough to rip it apart. Second, many large ocean vessels have propellers that exit the ship from underneath. These ships don't need a flat stern and you'll notice that they tend to have more of a stub than a point in the back. This is a compromise between size and efficiency.",
"A tapered stern allows the water to gently come back together to fill the hole the boat made as it passed. [The front and rear of the hull stay wet at the waterline](_URL_0_) \n\n Square sterns are more efficient on faster craft, where the water cannot flow back together fast enough. The faster shape is squared off, [so the water can detach from the back of the boat and not drag on it.](_URL_1_)",
"The ideal high speed ship is infinitely long and infinitely skinny, this gives the least amount of drag but is impossible to build.\n\nThe practical high speed ship is fairly long and fairly skinny at the water line, but this also makes it relatively unstable.\n\nA ship that is fairly wide relative to its length will be very stable; and make it a lot easier to put your stuff close to the water line which lets you carry more cargo with less of a risk of flipping over.\n\nShips that have a flat stern often aren't concerned about absolute speed, there is often something else they had to worry about more than just going fast. It could be overall length like on a speed boat. It could be a need to load cargo in from some side and a big rear loading ramp was convenient. It could be that they're a big ass ferry only ever doing 6 knots so what do they care about high speed drag.\n\nPoints on both ends help the boat go faster with the same horsepower, but not all boats care about speed."
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5qo2s8 | do gas giants such as jupiter and saturn have plate tectonics? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5qo2s8/eli5_do_gas_giants_such_as_jupiter_and_saturn/ | {
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"As far as we know, no.\n\nThey don't really have a true \"surface\" and the behavior of the upper layers are dominated by gas dynamics.\n\nOnce you get deeper into the mantle of these planets the gas is dense enough for fluid dynamics to take over and they behave more like liquids.\n\nWay down below the thousands of kilometers of gaseous sludge these bodies probably do have a solid core, but we don't know anything about how it behaves."
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7uga7g | When was the word "tyrant" given a negative connotation? | I was reading up on ancient Greece and their early forms of tyrants and my textbook made a note on how they weren't wicked or oppressive as our word "tyrant" connotes, but when did history start seeing absolute rulers as tyrannical in a negative way? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/7uga7g/when_was_the_word_tyrant_given_a_negative/ | {
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"About 2500 years ago. In fact, the Greeks started portraying tyranny as a universally negative and hated thing pretty much immediately after the early tyrants your textbook told you about.\n\nIn his brilliant article 'Before *turannoi* were tyrants', Greg Anderson showed that \"tyranny\" was not a negative term when it was adopted into the Greek language, probably from Lydian, in the 7th century BC. The earliest attestation, in a poem by Archilochos, seems to take the word to mean simply \"great power\" or \"great wealth\" - both of which were seen as desirable and admirable by Greek elites at the time. It seems tyranny was generally regarded as the prize at the end of the endemic factional competition for power and influence that marked the political life of early Greek city-states. As you say, the early tyrants are generally not known as despotic, oppressive rulers; several are remembered by tradition as champions of the people, who overthrew old leisure-class oligarchies, curtailed the power of greedy rivals and treated citizens to many benefactions. For example, all sources agree that Peisistratos of Athens, who ruled about 546-527 BC, ruled in accordance with the existing laws and adorned his city with temples, fountains and festivals. According to a student of Aristotle, his rule was remembered by the Athenians as an \"Age of Kronos\" (i.e. a golden age of fertility and prosperity).\n\nTyrants, however, represented the monopolisation of power in a system of rival factions; they often seem to have tried to make their position hereditary. In the more stable tyrannies, the sons of tyrants often succeeded to the position. These sons were rarely as well-regarded as the \"first generation\" of tyrants; it seems that Greek communities were perfectly happy to see a tyrant rise to power, but could not tolerate the notion of power remaining forever in the hands of one family. Possibly this is related to the idea that those rising to the tyranny in a context of elite rivalry must have been men of some political skill or military power, but those who simply inherited the position did not need to be men of any particular ability. However this may be, tyranny may have been a common form of government in Archaic Greece, but it rarely lasted more than two generations before being overthrown. Knowing this, successor tyrants were more likely to act aggressively to assert their power, which in turn increased the likelihood of inciting rebellion.\n\nThe Athenians maintained that they were liberated from an oppressive tyranny when two lovers called Harmodios and Aristogeiton assassinated Peisistratos' son and successor around 514 BC. The so-called \"tyrant-slayers\" became a rallying point of the young democracy; songs were sung to them, [statues made](_URL_0_), and honours were given to their descendants in perpetuity. However, inquisitive Athenians knew perfectly well that the story was false; we only know its details today because Herodotos, Thucydides and the aforementioned student of Aristotle all explain at length what they discovered about the actual situation. Harmodios and Aristogeiton, they say, were not enraged by the tyranny at all, but were simply involved in a lovers' quarrel. They may have plotted to murder both (or all 3) of Peisistratos' sons, but they attacked in haste and only managed to kill the less capable Hipparchos, leaving the true tyrant Hippias in charge of the city. Only then, driven to paranoid fear by the attempt on his life, did Hippias begin to rule with an iron fist. He had many citizens exiled or executed and generally seems to have inflicted a reign of terror on Athens in the hope of rooting out a non-existent conspiracy. Prominent Athenians like Kleisthenes called on the Spartans to intervene, and in 510 BC, Hippias was finally driven out. A few years later, Kleisthenes initiated the reforms that are regarded as the foundation of Athenian democracy. But the relevant question is: was Hippias always a hated despot, inspiring plots like that of Harmodios and Aristogeiton? Or was he hated only because of his violent reaction to the tyrant-slayers' attack, ironically inspiring Athenians of later generations to worship Harmodios and Aristogeiton as liberators?\n\nUnfortunately, it's hard to give a definitive answer, because this example is by far the best known, and it still remains largely hidden in the murky depths of Archaic Greek history. But the shift in attitude towards tyrants seems to have been a general feature of Greek political thought towards the end of the sixth century BC. It's at this time that Sparta makes a name for itself by going around deposing tyrants in states as far afield as Samos (and Athens, as noted above). From this time onward, tyranny is never again regarded even as morally neutral. It is always portrayed as evil, and becomes more so as the centuries pass. Fear and hatred of tyranny is a defining feature of Greek thought throughout the Classical period, and many features of Greek democratic government (magistracies filled by lot for short periods; administration by panels of magistrates and generals rather than single leaders; the institution of ostracism/petalism, by which the people could vote to send a chosen citizen into exile) are clearly intended specifically to prevent any single person from gaining too much power. Anyone who managed to gain prominence in politics immediately attracted suspicions of aiming for tyranny. Athens issued decrees to the effect that anyone caught plotting to establish a tyranny could be killed with impunity, and that all Athenian citizens were to swear that they would do so without hesitation. The writings of authors with more oligarchic leanings, such as Plato, Aristotle and Isokrates, show clearly that tyranny was hated by democrats and oligarchs alike; the latter may have argued that democracy was blind, lawless and unstable, but they showed that the same was true for tyranny. Even though one-man rule was on the rise in the fourth century BC, and some of the Greek world's most powerful political entities were intermittently run by tyrants (notably Syracuse and Thessaly), it seems to have been all but universally agreed that this was a bad thing, and that each of these states craved liberation.\n\nLater centuries built this indignation at the concept of tyranny to ever greater heights. Fourth-century tyrants like Dionysios of Syracuse became archetypes of the evil tyrant: men whose insatiable desire for power reflected their insatiable desire in general, and who were characterised by violence, wrath, greed, arrogance, gluttony, dishonesty, distrust, sexual perversion, and everything else that the ideal citizen would keep far from him. Greek and later Roman thought portrayed the tyrant as the anti-citizen - someone whose unrestrained appetites made it impossible for him to live a good life within the confounds of civil society, regulated as it was by laws, customs and traditions. From the mere exponent of socio-political processes, the tyrant had become their worst abberation.\n\nWhence the change? I've already noted that tyrannical dynasties rarely lasted long, and that there was probably some sense that one-man rule wasn't right even before the Classical period. This may well have been the product simply of rival factions wanting access to power; one reason for the success of Peisistratos' tyranny was that (as epigraphic evidence shows) he seems to have been able to co-opt other members of the elite in his system as long as it was understood who was really in charge. The process of tyrannical coups and their eventual violent overthrow also may have given tyranny some nasty associations with instability and even civil war, leading Greeks to seek to establish more stable systems of government. \n\nBut it seems likely that it was the increasing sophistication of Greek states and their institutions, and the accompanying growth of civic consciousness, that made tyrannies increasingly unpalatable specifically in the later sixth century BC. As ideas like citizenship, equality, and the rule of law became rooted in Greek thinking about political communities, it would have seemed increasingly absurd to them that one man should be able to do whatever he wanted to the rest. The arrival of the Persians put the final nail in the coffin of tyranny; Persia, ruled by a monarch itself, often used local tyrants as their loyal governors, increasing the Greek distaste for this unaccountable form of rule. As they developed systems that were more inclusive, more accountable, and more stable, they started seeing tyranny not as a feature but as an abberation, and eventually came to think that even murder was justified if it helped to get rid of them."
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e8yczh | Logistics of the mongol army during ghengis khan’s conquests | Ghengis khan had rapidly expanded the mongol zone of influence during his conquests while keeping his army intact and his new lands subjugated and under his control. However, I am curious how Ghengis khan had organized and planned the logistics of his far reaching invasions and how he administrated his new holdings. The vast swaths of land he controlled were often populated and keeping control over non core territories during the Middle Ages was a difficult thing to do. So I guess my question is how did Ghengis khan and his later predecessor, ogedei, hold onto their empire and plan the logistics of their invasions? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/e8yczh/logistics_of_the_mongol_army_during_ghengis_khans/ | {
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"I cover some of the logistics and tactics of the Mongol army [here](_URL_0_). And then I talk about some basic taxation and administration [here](_URL_1_).\n\nThe administration aspect of my second post is really broad, and it was because the question was broad in and of itself and diving into specifics *can* bore some people; however, I will expand a bit further for you since you're wondering how new holdings and probably older but more recent holdings were administered.\n\nSo, the Mongols get a lot of credit for rapid adaptation and rightly so; initially, under Genghis Khan, they would govern by using their military as a basis for their organization of society. Using this method they could get tribute from the more recently conquered lands; however, this wasn't a long term solution and as time went on, the Mongols realized the importance of taxation. Genghis Khan relied on some of his subjects that were more closely related, such as the Khitans who had recently ruled Northern China but were overthrown by the Jurchen even more recently. Likewise, in Central Asia they relied on the Kara-Khitai for the same reasons. These groups of people were great bridges for the Mongols in my opinion, though the Khitans were *proto-Mongolic* people, they had become more and more Chinese-like and although the Kara-Khitai were Turkic, they had become more and more Persian-like. You can see how these people could have been useful to the Mongols just from the *bridge* perspective I mentioned. Despite all this, the Mongols still appointed governors to these areas. Some sources claim that these governors were rotated in and out of these regions, which doesn't surprise me at all to be honest because Genghis Khan believed that the world could be conquered and ruled from horse back, and as history tells us, nomadic people were very prone to adopting sedentary like society when exposed to it.\n\nAs the Mongol Empire continued to expand and last longer this evolutionary process continued through the administration of Ogedei, (the second ruler) and by the time of Mongke (the 4th ruler), we see him trying to make the Empire more centralized and more bureaucratic, as he creates \"viceroy\" like positions to oversee the duties of these governors and census-takers once the Empire moved to a tax based system. Obviously as the Empire grew it was important to maintain stability through trade and agriculture as well, this was important especially because the Mongols controlled the sedentary peoples.\n\nI'm not sure if you meant to type predecessor, or if you meant successor; however, Ogedei is the 3rd son of Genghis Khan and will succeed him in ruling the Empire. In 1229 at the Kurultai, the Mongol nobility will vote to elect Ogedei as the new Great Khan of the Empire. Now, I'm a firm believer that Ogedei was simply brilliant - many have made the case for the youngest son, Tolui, or the oldest, Chagatai, and I can see where they are coming from, but I just find Ogedei from an administrative perspective to be great. Genghis Khan typically did everything from a military camp, sometimes you couldn't even find the man as he was always on the move. Ogedei knew that this would cause a problem in this ever evolving system, especially during the transition from tribute to tax based, so one of his first decrees was to have an imperial capital. Symbolism aside, it was nice not only for the Mongols but also their subjects as they now had a set place where they could deliver their taxes, show up for meetings and later, accommodate travelers and merchants . And thus, in 1235, Karakorum was to be constructed. I'd like to mention also that this didn't mean Ogedei had decided to settle, he continued to live a nomadic life-style. Ogedei realized that there was no way to implement his father's Yasa law on other people, so he implemented religious tolerance in what was now a multi-religious and multi-ethnic Empire, though I warn you - when I mean religious tolerance there is more emphasis on the word tolerance here. One detail one should remember, is that the Mongols considered other populations to be lesser than their live-stock and I highly doubt their opinion changed simply because they had conquered them (up to this point at least). Does this mean that everyone needed to be Mongol? Of course not, and Ogedei knew this, so he tolerated these other people.\n\nOgedei also invested heavily in infrastructure. These are not all new projects, some of them were expansions of what his father had begun. For example, stations were placed around the regions of Mongolia in which messengers could ride through very quickly and bring news to the Khan ASAP, and likewise he could send news out. What Ogedei did was simply expand it by creating stations that reached farther as the Empire grew and sped up the process by giving these people \"licenses\" or \"passports\" I suppose would be the better word. A rider could show up to one of these stations, flash their passport, swap out his horse and continue along. This made it possible to get news to everyone much more quickly."
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3cvzum | since a person's skin is constantly being renewed and growing back, why don't moles simply fall off after so long? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3cvzum/eli5_since_a_persons_skin_is_constantly_being/ | {
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"::Borrowed text:: \nYour skin contains several different types of cells. The skin cells you're thinking of that regenerate and slough off every so often are called keratinocytes. The cells that make up moles/birthmarks are a different cell type called melanocytes. Melanocytes do not get replaced by keratinocytes. \n \nAs far as cancerous moles go, the skin regeneration is the problem! UV light causes damage to cells by forming abnormal linkages in the DNA. Often this damage can be corrected, but the more UV exposure, the more damage that occurs. If it cannot be corrected, then it is possible that certain regions in the DNA are not read correctly during replication. Some mutations can cause this new cell to become immortal, and it will keep on replicating. This abnormal growth is cancer.",
"The top layer of skin has a foundation of skin stem cells. Some of these cells die and are pushed up to become the top layer while the rest stick around and continue to reproduce. Moles are **in** the same state (not all moles are the same), but I **think** most of them also have a base layer of cells that a number of them stick around so they can continue to reproduce. These cells are decedents of the original mole cells so they have the same mutation(s) and therefore the same traits.",
"When I was younger i had no moles on my face but after a very bad sun burn and a layer of my skin peeled, it revealed a mole on my nose bridge. Apparently the mole has always been there but we couldn't see it because it was covered by a few layers of skin. And this mole on my nose bridge faded alot the past 18 years. Now it's just a light brown mole. ",
"I used to have dark freckles in the palms of my hands (one near the center of each palm). My friends and I referred to them as my stigmata. Twenty years later, they're gone. I don't know when they went away, but I'm obviously now cursed. But I guess (with divine/satanic intervention) freckles can disappear. ",
"Some are genetic and actually present in the womb. They regenerate like any other skin. But there are many different types.",
"why only moles? Why don't you question freckles as well?",
"I think the best way to think about the skin is in [layers](_URL_0_). As you can see, our \"skin\" is made up of the Epidermis and dermis with underlying subcutaneous tissues. The epidermis and dermis are separated by a layer of cells known as the \"basal cells\" which makeup what is known as the \"basement membrane\" at the dermal-epidermal junction. Basal cells are the cells which are responsible for regenerating our epidermis but themselves are never shed (basically specialized stem cells). As illustrated in the linked image, melanocytes (cells responsible for making our skin pigment including hyperpigmented areas we call \"moles\") are located in-between basal cells. Given that this layer of skin never sheds, moles aren't shed.\n\nAs a side note being that burn injuries are an area of interest, [we rank burns in \"degrees\" based on which of these layers are disrupted/injured by a burn.](_URL_1_) 1st degree burns involve just the epidermis, then superficial second degree burns extend down to the dermis with partial disruption of the basement membrane. Deep second degree burns dip down to involve the full dermis and third degree burns or \"full thickness burns\" involve both the epidermis and the dermis and extend down to the subcutaneous tissue..there are 4th and 5th degree burns which imply involvement of subcutaneous tissues (muscle, fat, ligaments) all the way to bone. The extent of loss of the basement membrane and depth of burn corellate with severity of scaring as well as dictating the requirement for skin grafts to help with healing.\n\nSource: Pediatric doc heading for ICU subspeciality with focus on burn management"
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4g2lpb | Were Counties named for Counts, or Counts named for Counties? | Hi! I know, it's one of those frustrating and controversial questions about Feudalism. However, it is an honest question that I'd love to here some expert and knowledgeable opinions on.
Basically, were the landholdings *named* for the noble who administered them (i.e. therefore the original noble was measured by his own merits, given a title of a specific rank, then given holdings that were thus classified), or were the nobles named for the landholdings they were granted?
I know there would probably be iffiness with regard to this chicken-and-egg question, but I mean the original nobility (the ones whom everyone else inherited their titles and holdings from).
For example, 'Counts' are called such as they are nominally 'companions of the King' (i.e. his most loyal men). So given that, would a person who gained the title Count due to his service under the King when he did his original conquering, when given landholdings as a reward and a bond, would the landholdings be named 'Counties' to match his title?
Or did medieval land-surveyors look at the area, divided and categorized them by value as either baronies, counties, duchies, etc. Then someone who did well would be granted so-and-so land as a benefice, and since the so-and-so land was classified as a county, he would be called 'Count'? I'm sure the land chosen for him would be picked to 'match' his achievements, but the technical question of which is named first is of academic curiosity to me, I think.
Specifically because if noble are named for pre-categorized landholdings, then it must mean that there are a limited number of counts, barons, etc. that can be named. If a landholding is instead named for a noble, then a monarch can theoretically ennoble as many counts as he or she would like, and their holdings would then be elevated to the status of being a 'county'.
What do you think?
| AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4g2lpb/were_counties_named_for_counts_or_counts_named/ | {
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"OK, I think firstly there's a misconception in your post that a count 'owns' his county, or has control over all the land within it. This was never the case in medieval Europe. Counts very often owned substantial amounts of property outside of the counties they ruled, and could (in theory if never in practice) rule a county in which they owned no land whatsoever.\n\nIn terms of your question as to which came first, counties predated counts by quite a bit, in the former Roman empire at least. Most counties were based on the old late antique city territories (*pagi*), just as most episcopal dioceses were, which is why, for the most part, medieval counties and dioceses are coterminous. This did change, especially after the year 1000, when weaker central control, particularly in France, allowed powerful aristocrats to either create new independent counties for themselves or to amalgamate several counties into one.\n\nCounts were appointed by kings up to c.900 AD, and were usually a person who had considerable land and influence within the county already; since Early medieval government and administration was so simple, a count needed local resources in order to be effective. The count was given control of the royal lands (the fisc) within the county, but this wouldn't usually have been enough to fund a count's activities on their own. \n\nFrom about 900 onwards, counties tended to drift out of the King's control and counts inherited from their counties from relatives, rather than being appointed by the king. So who controlled the country depended on who was count at the time when central control weakened to the extent that counts could go it on their own.\n\nI'm on mobile, so haven't been able to give a super detailed answer, but feel free to ask follow-ups on anything I've been unclear about. I should also add that this answer is based on the Carolingian empire and its successor kingdoms. As far as I know England is very broadly similar, but royal central power over the aristocracy was stronger for most of the middle ages: hopefully some can come along and add more details on England, since I don't know much about it."
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59ddak | why are so many endangered animals used in chinese "medicine"? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/59ddak/eli5_why_are_so_many_endangered_animals_used_in/ | {
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"The rapid industrialization of Asian economies means that there are a lot more people in the Asian middle class who want to be able to show off their means. As a result, demand for \"traditional\" remedies (they aren't actually that old, but that's a story for another time) has skyrocketed.\n\nThose remedies were from rare or difficult to catch, but not endangered, animals because it increased their mysticism. Nobody's going to buy your essence of rat to cure a hangover, but they might buy essence of pangolin because they don't know what a pangolin is and it sounds like magic. Rhino horn has a similar background in this regard: found only in a faraway land, rare, etc. The increased demand has, therefore, caused the endangerment of these animals.\n\nIt's not that they deliberately chose endangered species. The species became endangered as a result of changing economic realities.",
"Because they're usually large and powerful animals that they believed you'd gain the powers of etc."
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a9jnz4 | What factors led to the emergence of city-states in Ancient Greece and during the Italian Renaissance? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/a9jnz4/what_factors_led_to_the_emergence_of_citystates/ | {
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"While Classical Greece and Communal Italy are two completely different time periods in two different geographic spaces, there are some communalities in Mediterranean urbanization. I brought that up in a podcast episode about communal Milan [here](_URL_0_).\n\nRegarding the specifics of Italy, the development of urban-centric political, social, and economic institutions has to do with the characteristics of the peninsula between the basin of the river Po and Rome. You see, it is not a consequence of happenstance that the heartland of Europe's greatest empire, that of Rome, was a peninsula that could support dense urbanization thanks to high agricultural productivity, capped off with navigable rivers and generous coastline helping foster strong internal and external trade links. \n\nSo once Roman institutions definitively evaporated with the fall of Theodoric's Ravennate monarchy, the two post-Roman kingdoms of Italy (Lombard and Carolingian) already had an enormous potential for regional instability. With relatively small power bases leading aristocrats could easily challenge the state; while the state, such as it existed, even in times of tranquility could never adequately develop the necessary capacity to affirm itself on the entire peninsula. And let's not forget that Lombard Kingdom in particular never even consolidated nominal control of the entire peninsula, with corridors connecting major areas of urban productivity controlled by the Eastern Empire. Indeed, not only did the wars of Justinian do much more to devastate, depopulate, and destabilize Italy than any sack conducted by the late roman armies and barracks emperors, but the continued byzantine presence on the edges of the peninsula would deepen geographic fragmentation and contribute to the lack of a unitary system of governance and control. So while in the rest of Europe the seeds of nation-states were planted over the course of the post-roman transformation, Italy would be in a state of near-constant division and crisis, principally because it could afford to. It has been argued that crisis would be the defining feature of the Italian political system until the end of the communal period. \n\nTwo foreign rulers who would call themselves Emperors, Charlemagne in the eight century, and Otto in the ninth, would take advantage of an Italian leadership so divided it could not muster an effective opposition to a foreign threat. It is telling that there is no Italian counter-equivalent figure comparable to Otto and Charlemagne. Both Charlemagne and Otto faced off against Italian monarchs who were, theoretically, at the height of their power. And both Charlemagne and Otto's Kingdom of Italy would degenerate into regional factionalism and disorganization. I wrote in-detail about the disintegration of the Carolingian kingdom in [this answer here,](_URL_3_) if you're interested. I also wrote about the decentralization of Otto's empire [here](_URL_1_).\n\nThe perseverance of ill-fitting legal and administrative constructs dating to the Roman Empire, revitalized by Italian kings and foreign Emperors alike in order to justify rule both inside and outside of the Italian peninsula, might have contributed to the continued lack of any successful system of administration attuned to the present needs of Italy. However, this Roman heritage and cultural baggage meant that at the local level the peninsula continued to be well-administered. The urban-centric legal holdovers from the Roman period fostered political enfranchisement for property owners, courts upholding rule of law, and as a consequence, upholding the ability to conduct trade and retain prosperity. \n\nThe Roman marketplace and courthouse, called *Basilica*, had also accrued religious functions to create a social, legal, and cultural reference points in the Italian cities, often headed by a religious authority: the local Bishop. Thus landowners converged onto urban bishops asking for arbitration of disputes, merchants asked for privileges in the marketplace, and in a general sense these communities created a system rule by voluntary convergence. This form of government called the \"Commune,\" would recognizably emerge at the start of the 11th century. \n\nBut as I mentioned [yesterday](_URL_2_), while this sort political organization was certainly easier to set up in urban communities, a strict conception of the phrase \"City State\" can be limiting. \n\nThe \"Comune\" could transcend the geographic space of the city and its hinterland, even surviving its physical destruction (as happened in Milan in the 12th century) or geographic migration (as happened to Venice in the 10th century). The \"Comune\" could also impose itself with varying degrees of control over satellite communities, or it could itself submit to an outside authority, even accepting submission to a single sufficiently influential or charismatic person (as happened in Verona in the 14th century). But, most importantly, the construct of the \"Comune\" could itself be called into question, with frequent crises and expulsions of formerly enfranchised parties as the terms of the social contract were modified and renegotiated. The urban context is a vital feature, but it is not the only feature. "
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8whew7 | Why can I see star clusters better when they’re in my peripheral vision? | I oftentimes find that I can see clusters of stars (sometimes just a couple slightly larger ones) better out of the corner of my eye. But tonight I observed what I’m assuming is part of the Milky Way better when not directly looking at it. In fact, when directly looking at it, I really couldn’t make out many stars.
Why might this be?
Edit: this has been super informative, thanks for all the insightful answers!! | askscience | https://www.reddit.com/r/askscience/comments/8whew7/why_can_i_see_star_clusters_better_when_theyre_in/ | {
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"There are 2 types of photoreceptor cells in the eye: rods and cones. Rods are more sensitive to light than cones, and they are more concentrated on the edges of the retina. Thus peripheral vision is more sensitive to faint lights. When you look straight at the stars the light falls on centrally located cones which are less sensitive to light, and you can't make out the stars.",
"Because the peripheral part of your retina has more rods, which are a lot better at detecting light. The central part of your retina has mostly cones, which are good at seeing color (but aren't very good at detecting weak light). If you want to see something at night, circle your eyes around it, don't look directly at it. ",
"This is definitely something astronomers take in to consideration when looking through a telescope. When youre looking at extremely dim stars or other deep sky objects, you get a better view using \"averted vision\", which is looking not directly at the object, but just to the side to get a cleaner, crisper view. \n\n",
"What you’re describing is what people in the observing hobby refer to as “averted vision”. You’ll find if you look 8 to 16 degrees to the side of an object that is very feint you’ll be able to see more detail. With practice you’ll get better and better at it, too, as you get used to viewing things slightly out of the side of your eye.\n\nHere’s an article that describes the practice of using averted vision: _URL_0_",
"Haven't seen anyone else here mention this yet, but humans have a blind spot in the center of the field of vision of each eye where the optic nerve connects to the back of the eye. You don't notice it because your brain just sort fills it in with whatever it assumes would be there. This is most noticable if you look directly at a single star, it will disappear completely, but if you look just to the side of it, it will reappear. A demo: _URL_0_\n\nEdit: Not in the center...off in the perifery. Thanks all for the correction.",
"I *think* it's in *Broca's Brain* (not sure), but Carl Sagan answers this exact question, which was asked by some drunken partiers who called up the local observatory wondering if they were going crazy because they also experienced this. Sagan gives the same excellent explanation as /u/perekele above.",
"Averted vision is a common technique used in amateur astronomy, through the telescope or naked eye. If you look directly at the Pleiades naked eye from a dark sky location, most people will see six or seven stars in a small dipper shaped figure. If you look at it with averted vision, you'll see a fuzzy patch about the size of a postage stamp at arms length, which is the combined light of the hundreds of stars in the cluster. It will really pop out at you.",
"To add to what a lot of people are already posting, a great technique for seeing in the dark is to look just away from whatever you're trying to see. You're basically maneuvering with peripheral vision only, but you can still get around!",
"Good job in noticing this phenomenon.\n\nThe center of your eye (the part you use when looking directly at something) is very sensitive to color and detail in daylight conditions where there is plenty of light. The rods which are good during low light conditions are everywhere else in the eye. So looking directly at something in the dark is not the way to go.\n\nThey say 15 degrees is a good angle to look \"next to something\" to see the thing itself best in the dark."
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aagwx8 | why do kids and adults with kids seem to get vomiting type stomach bugs so often? | I haven't thrown up in over 10 years. But a family I know just came down with a puke fest - 3 kids and 1 adult had a stomach bug at the same time. I saw on FB people talking like their families were experiencing the same thing, all with kids. Why do kids spread this thing around so commonly? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aagwx8/eli5_why_do_kids_and_adults_with_kids_seem_to_get/ | {
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"The sorts of bacteria which cause that type of gastrointestinal illness are easily controlled by handwashing and good hygiene. Children are bad at that kind of thing so they speak those bacteria quickly, and then spread them to their parents who become ill themselves.\n\nEdit: *handwashing, not hanging. Equally effective.",
"Children do not keep good hygiene (Most of the time) because they are still learning how to do so. This means that they will be exposed to more of the pathogens that cause stomach bugs. In turn they will catch said bugs more often, and they will spread them to those around them (including parents) more often. ",
"It’s incredibly contagious and kids are sent to school sick all the time. Responsible parents keep sick kids home, but even washing hands constantly won’t protect you completely. Vomiting can make particles airborne and it takes very little of the virus to spread. \n\n\nSo kids get it quickly at school, and spread it at home. It goes around about 2-3 times a year at my school. \n\nAs you get older though you can get some immunity (I think anyway) to some viruses. Some people also lack enzymes to get sick from specific strains and just spread it without any symptoms. \n\n\nKids are also the worst at communicating and controlling their symptoms. I’ve seen some just say their tongue felt weird and vomit on everything, others have screamed “SOMETHING IS HAPPENING.” and puke. My favorite though are the ones who know they’re sick but hide it so they don’t have to miss anything. Like the kid who barfed mid Christmas performance.\n\nAdults typically go to the bathroom, stay home, or find a trash can. Then wash their hands and try to contain it.\n\nKids just walk towards you covered in vomit crying getting things everywhere and spreading germs everywhere.",
"No one has mentioned yet that kids’ immune systems are not fully developed either. So they have less defenses in addition to crawling around on floors, licking everything and picking up old cigarette butts and dog poo.\n\n",
"Gastroenteritis (the “stomach flu”) is most commonly caused when a person ingests the infected fecal matter of another person. It’s very easily preventable through proper hand-washing techniques. As kids are pretty lax in that department and tend to touch random things and then their own faces/mouths without any thought, they spread it easily. \n\nIn theory, if you wash your hands properly before every contact you make with your own mouth and nose - and if the things you put in those places are clean - you could go your whole life without ever dealing with gastroenteritis.\n\nI’m an emetophobe. I avoid children like the plague. "
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14spbf | How are cures for poisons developed and how are people treated when a poison is unknown? | askscience | http://www.reddit.com/r/askscience/comments/14spbf/how_are_cures_for_poisons_developed_and_how_are/ | {
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"The symptoms would be managed. If they go into shock, they'll receive adrenaline and fluids to boost their blood pressure. Cures are developed in many ways, usually through rigorous biochemical studies. A slightly newer way to make cures for venom is through antibodies. \n\nThe short version is this. A new venomous snake is discovered. The venom is a protein. We inject small amounts into a horse, or goat, or whatever, and gradually step up the dose, making sure not to kill the host organism. Over the course of weeks, the organism will make antibodies against the poison. The can be removed and attached to human proteins and stored. When someone gets bit by the new snake, these vials of anti venom can be administered, and the body will know to clear the toxin quickly."
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||
1inj0y | Sending Energy to Space? | I have a question regarding the earth and the conservation of energy. If energy can not be destroyed but only changes form, and the suns rays are continuously sending energy to earth, then what process expells the energy into space?
| askscience | http://www.reddit.com/r/askscience/comments/1inj0y/sending_energy_to_space/ | {
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"Radiation. Some of the sun's energy is reflected and some is absorbed. The absorbed light can be re-emitted as light/heat, back into space.",
"Nothing technically says the earth has to expend the equivalent energy it gains from outside sources, mainly the sun. But the energy does get expended through radiating heat, and reflected light. Radiation is one (atleast at a most basic level) of the only heat transfer methods that work in a vacuum. ",
"The black body radiation of earth. However, as it happens the energy radiated by the earth and the incident energy from the sun are not equal."
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25x07z | why does it hurt our eyes to look at the extremes of our vision? | I've always wondered why looking way up, down or to the sides causes pain in our eyes. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/25x07z/eli5_why_does_it_hurt_our_eyes_to_look_at_the/ | {
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"It's because the eye is a ball connected by a thread of nerves to the brain.\nI'm fairly sure that it's because stretching the nerve thread that causes the pain ",
"Your eyes can't rotate themselves, obviously - it must be done by muscles.\n\nIf you try to rotate/move any muscle past the point it's built to rotate to, it'll hurt - for an example, hold your arm out in front of you, then swing it 180* so that it's pointing directly behind you.\n\nYou can't do it without moving your shoulder, or dislocating your arm, and it'll hurt when you go past the point at which your muscles are used to dealing with.\n\nSame idea. Muscle moves the eye, but can only move so far."
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xugm2 | So what's the real difference between an archaeologist, historical geographer and a historian? | Im sure this sounds like a dumb question to someone who engages in these but Ive recently read a different book by each type of author and they all seem like "history" but perahps with emphasis.
| AskHistorians | http://www.reddit.com/r/AskHistorians/comments/xugm2/so_whats_the_real_difference_between_an/ | {
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"Easy, one digs up old maps, one redraws old maps, whilst the other debates old maps until the ends of time. But no seriously, I think that is it at a fundamental level. Archeology seems a lot more hands on though, and therefore the most rewarding I think. I know a dutch specialist in Meso-America. He gets to spend every Summer digging in the Atacama for old burial sites, and has quite a gourd collection!",
"Realistically it comes down to a difference in methodology. Historians place the greatest weight on documents, Archaeologists on material remains, and geographers on maps. Each considers their specialty the most reliable. When things are going well the three work hand in glove, although they tend to squabble sometimes. \n\n",
"Geography is not simply the study of or drawing of maps. \n\nHistorical geography instead focuses on the influence of environment and place on historical issues, or the way history has shaped a place. historical geographers look at an area and analyze how it has changed over time. \n\nGeographers organize their data primarily by place. Historians categorize their data primarily by time. However, both fields must take into account multiple factors. \n\nArcheologists deal with the material remains of human cultures in order to create conclusions about a society, which are further developed by historians. "
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14tmk0 | What exactly is happening in a meteor shower like the geminids? | Is the Earth just flying through a stationary cloud of busted up asteroid parts? Do these rocks sit in our orbital path, or does our orbit cross theirs? Do they all burn up or do some land? | askscience | http://www.reddit.com/r/askscience/comments/14tmk0/what_exactly_is_happening_in_a_meteor_shower_like/ | {
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"Your answer is pretty much it. \nA short time ago, a comet would have flown through our orbit, and it left a cloud of dust and particulates behind. Now, the earth is flying into the cloud, and those particulates are burning up in the atmosphere as we run into them. This is what makes it look like all the comets are 'radiating' from one point (in the case of the Geminids, the constellation Gemini) \nThe geminid cloud is left behind by [Minor planet 3200 Phaethon](_URL_0_) "
]
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9tp52w | how does a casino make money on poker if the dealer doesn’t play a hand? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9tp52w/eli5_how_does_a_casino_make_money_on_poker_if_the/ | {
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"They take a \"rake\" of every hand. So if everyone combined puts in $100 in chips there might only be $98 in the pot. The other $2 is taken by the casino."
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||
2qsiao | When we feel emotions due to music, is it conditioning from prior experiences, or do certain sounds have the ability to make us feel certain emotions? | I'm not certain this is the right subreddit for this. It's more psychological, I suppose. My question is, when you hear a particularly depressing song that has no lyrics, Moonlight Sonata for example, do you actually feel moments in the song because you're conditioned to understand certain moments of the music with emotions, or do you feel it because the sound actually has the ability to invoke certain emotions, regardless of your upbringing or association with certain types of music?
Is it possible that a child, somewhere under certain strange circumstances, could be conditioned to associate "upbeat" music with gloom and depression, and "downbeat" slower music with happiness and joy? Would they truly feel the emotions the way we do with music?
If we plucked someone from the middle of nowhere, who'd never heard music as we know it, and asked them to listen to a "sad" musical score, would they identify it as such? | askscience | http://www.reddit.com/r/askscience/comments/2qsiao/when_we_feel_emotions_due_to_music_is_it/ | {
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"There is a lot of scientific speculation about the ultimate nature of music. Musicologists have pointed out that there are types of music that are alien to our western culture, particularly Gamelan orchestra music, which most people find incomprehensible. It follows that at least to some extent, our response to music is learned. But there is also a deeper level to music. The beauty of music comes from the pattern recognition ability of the human brain. There are many important evolutionary advantages to being able to recognize patterns, which is a large part of what we do in order to make sense of our environment and experiences, but once you have that capacity to recognize patterns, then there will also be the capacity to recognize aesthetic patterns, as a kind of evolutionary side effect. The precise dividing line between learned musical response and innate pattern recognition cannot be drawn at this time."
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1uyemw | how do we exactly know we and everything around us is in three dimensions? isn't the universe just one dimensional line curved so much we can't really tell if we live in 3d or this one dimensional line? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1uyemw/eli5how_do_we_exactly_know_we_and_everything/ | {
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"We don't really *know* this, but it certainly looks like it for practical purposes. [Minutephysics explains one test here.](_URL_0_)",
"Because the min. number of coordinates you need to give to state where you are spatially is 3. By definition that's a three dimensional world. "
]
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"https://www.youtube.com/watch?v=SJJhHknEDPY"
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1kju3f | why are unpaid interns bad but unpaid volunteers good? | I'm curious: Why do Americans object to unpaid interns but at the same time praise unpaid volunteers?
[Habitat for Humanity](_URL_1_), for example, builds houses for the poor almost exclusively with unpaid volunteers. They don't get criticized. Even labor unions don't seem to object that Habitat is taking away paid construction jobs.
But other nonprofits like [the one Sheryl Sandberg started](_URL_2_) get strongly criticized, sometimes with what seem to be [overly-inflammatory headlines](_URL_0_) based more on populist hating of the rich than clear arguments about why unpaid interns are wrong whereas volunteers are right.
I've seen [some articles try to address this question](_URL_3_), but they seem to almost always end up just ragging on the person in charge for being too rich rather than making a clear case about how internships and volunteerism are different and why one should be compensated while the other shouldn't.
I would love to know if there really is any difference, or whether the distinction is ignored just because the economy is bad so everyone is cranky and needs more money. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1kju3f/eli5_why_are_unpaid_interns_bad_but_unpaid/ | {
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"Volunteering is considered to be done as an act of charity. As in, you aren't supposed to be doing it for money, but because it is a good act.\n\nInterning isn't like that. You aren't working 8 hour days fixing 20 year old code that makes no sense out of the goodness of your heart.",
"The big distinction is that Interns are there for work experience. Volunteers are giving their time as a gift to a cause, while interns need experience to get a paying job in their field. This means that Interns may be doing free work for a company that they could otherwise have a job with because the company doesn't want to hire people without work experience.\n\nThis does not mean that interning is bad though! Often times interning is a fantastic opportunity for people to learn hands on about a complicated field of work without needed prior knowledge or experience, e.g. interning at NASA as a high schooler.",
"Volunteering is an act of charity. It does not take up all of your time and you can stop doing it without any penalty.\n\nAnd internship is an actual job, often doing work worth well above minimum wage pay rates, and very often working more than a full-time job. You do not only not get overtime but you do not get paid at all. All of this is in the hopes that the training, references and networking is enough compensation. It is not. It is companies trying to bypass the labor laws to pad their pocketbooks. \n\nI am fine with having internships being low pay, even minimum wage, due to the compensational benefits and the fact that they are in training, but no pay is slavery. ",
"If someone is making money off your work, then you should too. \nWith volunteer work, pretty much everyone involved is giving away their contribution (be it the time, skills, money, or products they've created/bought); with intern work, hardly anyone except the interns are working for free and the company often (perhaps indirectly) makes money off their work. \n\nYes, I know, you're gaining experience all and that, sounds nice in theory, but in practice it's too often taken advantage of. And guess what, regular paid-workers are gaining experience as well, in addition to being paid. \nSo, if the company if making money off your work, you should get paid for it."
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"http://www.habitat.org/",
"http://leanin.org/",
"http://www.theatlanticwire.com/business/2013/08/sheryl-sandberg-should-know-better-ask-interns-work-free/68355/"
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szxxb | What are the odds of winning an expert Minesweeper game ? | Assuming that you don't make any mistake, that the only times you lose are because it was logically impossible to find the mine. | askscience | http://www.reddit.com/r/askscience/comments/szxxb/what_are_the_odds_of_winning_an_expert/ | {
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"so... what you're really asking is what fraction of legal board layouts in minesweeper are not solvable.\n\nthis is a tricky question to compute, mostly just due to the size of the space of configurations. you would have to identify all motifs that logically have multiple solutions and then play the combinatorics game of how many ways to orient those there are, and how many different ones can you have on the same board, etc etc.\n\n[edit] by the way, there are a total of 560220999337421345429058985775821108059290502723897901281458809527214479570631168198385673295159633481600 different possible expert games of minesweeper.",
"I don't think it's feasible to ever compute these odds. The total number of possible Minesweeper boards is astronomical, making exact computation impossible even if you had a fast method for finding the odds that a particular board will be won.\n\nYou could sample a smaller number of boards to estimate the odds of winning, but that would require a method for optimal play, which I'm pretty sure is still unknown. A quick web search turns up some Berkely discrete math professors who [think optimal play is infeasible, but don't prove it](_URL_2_) (their probabilistic solver is the best solution I've seen yet for optimal play).\n\nFinding a method of optimal play that could be quickly executed (i.e. in [polynomial time](_URL_1_)) would probably get you some kind of [award](_URL_0_). Checking whether a configuration of flags results in a legal board (possibly, but not necessarily, required for optimal play) is a [difficult problem](_URL_3_), but there might be an optimal method of play that doesn't require doing that.\n\n**tl;dr No one knows**",
"This has been bugging me since I saw it, and i was bored today so i decided to find out. I wrote a program to play thousands of times and see how many of them it won. I think my algorithm was pretty exhaustive as far as only guessing when it needs to, although its guesses could probably use a little statistics love (though I gave it some logic for this, it tries to guess reasonably well).\n\nanyways, when all was said and done, here are the numbers (I got the same ones all 3 times I ran it, making me think my sample was plenty big). These are including all losses, including when your first square is a mine and you're forced to guess at the end (though a correct guess is a win, obviously)\n\nbeginner - won 79% \n\nintermediate - won 62%\n\nexpert - won 22%\n\nAs I said, the algorithm's guesses could use some love as far as good guesses and also as far as guessing something that is more likely to give you useful information to make it less likely that you will need to guess again - but now it's starting to be more complicated than I was going for, and looking at the other comments, isn't even a solved problem. so playing perfectly (if that's even something doable), you could likely add about 3-5% onto these numbers, or possibly even a little more."
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"https://en.wikipedia.org/wiki/Millennium_Prize_Problems",
"https://en.wikipedia.org/wiki/P_versus_NP_problem",
"http://www.cs.berkeley.edu/~daw/teaching/cs70-s05/Notes/lecture25.pdf",
"https://en.wikipedia.org/wiki/Minesweeper_\\(computer_game\\)#Computational_complexity"
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c3vr8f | when we focus on a moving object we can smoothly move our eyes however if nothing is there we cant smoothly move them from left to right? | Not sure how to word it but let's say you're focusing on a bird in the sky moving our eyes move smoothly to follow it
however if you try and move your eyes from left to right with nothing there it cant be done smoothly you more or less focus on different random spots to move them from A to B | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/c3vr8f/eli5_when_we_focus_on_a_moving_object_we_can/ | {
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"someone might explain it better. but our eyes are lenses . constantly adjusting based on how far the distance is.\n\nwhen you focus on a moving object which is a predictable trajectory (e.g. bird) our eye locks focus and we can easily follow it.\n\nwhen there is NOTHING . the distances vary as we move our eyes. (we cannot focus on nothingness which does not exist between your eyes and a far off distance) . so while you start moving your head. you might initially see something near like your next door building. then a pole maybe. then a far off building. then a far off monument . some people . heavily varying distances. and our eyes keep adjusting focus for them. working overtime. so it wont be smooth.\n\nimagine a hypothetical bird which could instantly also move perpendicular to its flight of path. that too instantly (like a teleport kind of thing, nightcrawler from x men) . our eyes would similarly go crazy then.\n\none interesting thing you will see , especially in yesteryear's special effects filled movies that actors are supposed to look at NOTHING (where a hologram or some cgi thing will be added later). and they are focus on all the wrong spots etc. and they look super weird since their eyes are not given a proper focus point.",
"Horizontal saccades (eye movements) feel like they are smooth, but they aren't.\nThey are always somewhat jerky, but your brain corrects the visual input so that you interpret it as smooth movement.\nWhen you have a moving object this allows the brain's \"correction software\" to do a more convincing job of making you think it was a smooth movement."
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53f0u9 | why can some people withstand more spice than others? | I mean spicy food | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/53f0u9/eli5_why_can_some_people_withstand_more_spice/ | {
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"there's actually an interesting Vox video just about this question. [\"Why we learn to love spicy food\"](_URL_0_) ",
"Capsaicin, the hot stuff in hot chillies, is a drug that acts directly on the nerves that signal heat and pain. The body responds with its natural pain relief system, endorphins to suppress the hurt, the effects are pleasant.\n\nLike nearly all drugs that interact directly with nerves the body builds a tolerance to it. On first exposure it may be unbearable but repeated low level use results in tolerance, increasing use leads to increased tolerance.\n\nI used to chase that endorphin buzz all the time to the point that if someone asked me \"Is this hot?\" the best answer I could give would be \"You are asking the wrong guy!\""
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q8y3g | Would Segregation Have Been Abolished Without Brown v. Board of Education? | I ask this question because I'm currently a law student who studied history as an undergraduate. In my Constitutional Law class we're currently talking about Originalism and its attitudes towards judicial review and judicial activism.
That prompted me to wonder if the USA would have abolished segregation without SCOTUS leading the way. I know the late 1950s and early 1960s saw a ton of legislation related to civil rights and there was a successful amendment in 1964 abolishing the poll tax but would they have occurred organically without judicial trailblazing?
I'm curious to hear from my better colleagues about whether there is evidence to support the idea of a strong popular and legislative assault on segregation without sanction from the highest court in the country.
Also for the purposes of discussion, lets take Brown v. Board to mean any repudiation of the "separate but equal" formulation from Plessy v. Ferguson. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/q8y3g/would_segregation_have_been_abolished_without/ | {
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"Actually, there was a looooong history of chipping away at [Plessy vs. Fergouson.](_URL_4_). Essentially it largely came down to before BvB.E., that you had to provide equal but seperate, which meant that the states had to provide a black law school. I know that in [Sweattv.Painter](_URL_1_), they basically made Texas have to create a black law school for equal access, so the SCOTUS had a long history of chipping away.\n\nAs for desegregation without SCOTUS, I think we would have to thank the Nazi's and Soviet's for that. After WWII, it became really hard to justify segregation in the armed and federal services based on race (interesting note, federal service wasn't segregated until Woodrow Wilson!), after fighting an enemy who based their philosophy on racial purity and segregation. How could the U.S. honestly justify itself as the torch of freedom if it wasn't free. This is why Truman integrated the services in 1948...which was a HUUUUUUUUUGE deal.\n\nLater, the Soviets used the [\"And you are lynching Negroes\"](_URL_3_) counter argument against the U.S. in painting them as villains. How could the U.S. claim it was better than the Soviets when there was systematic and institutionalized racism? Mounting pressure in the 50's and 60's would probably have forced most likely the Democratic Party to move to further integration (please note the history of the [Dixiecrat](_URL_2_) party). Eventually something would have hit SCOTUS to force them to act which would be acting with a probably more militant Civil Rights movement (with Brown v. Board, Martin Luther King had a legal basis for his movement, without it, more militant types like Elijah Mohammad and Malcolm X as well as the Black Panthers would have had to use more...extreme measures). I would put the Civil Rights movement about 10 to 15 years behind the power curve without _URL_0_, but it would have eventually happened as the Court would have had social pressures to hear a case of that type, and honestly Plessy v. Ferguson was a relic of it's time and really was unjustifiable."
]
} | [] | [] | [
[
"B.v.BE",
"http://en.wikipedia.org/wiki/Sweatt_v._Painter",
"http://en.wikipedia.org/wiki/Dixiecrat",
"http://en.wikipedia.org/wiki/And_you_are_lynching_Negroes",
"http://en.wikipedia.org/wiki/Category:United_States_racial_desegregation_case_law"
]
] |
|
3npm0d | What alternative historical lenses have been growing in popularity among historians? | I'm interested in alternate historical lenses to view world history from, and was wondering about any modern methodologies or research you have read/conduct with a "unique" view.
For example, most people are familiar with Marxist, Feminist, or structuralist narratives of history. But I've heard some historians discuss culinary/food histories as a lens or frame. I've seen specific products followed (alcohol, cod, salt, etc), primarily Nationalist frameworks, and climate narratives.
So, are there any new developments in historiography of new lenses to frame research or a historical narrative? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3npm0d/what_alternative_historical_lenses_have_been/ | {
"a_id": [
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"score": [
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"text": [
"Those books on salt, cod, etc are usually lumped under \"microhistory\" which is actually one of my favorite easy-reading history categories, I would read a popular microhistory on just about anything. HOW JARRED MAYONNAISE MADE THE MODERN WORLD AND EVERYTHING IN IT! I just love reading those out-there arguments in microhistory. \n\nDisability studies is one that's come into my radar recently, for eunuchs and castrati. It basically looks at historical times and what it meant to be disabled or able-bodied in those societies. So analyzing the castrated body, was it considered disabled in that society, if so, in what ways? I'd say disability history is part of the larger trend in [body history](_URL_0_), which works with things like, what values and meanings did society map on the body? I find body history pretty brain-stretchy when I read it, but I quite like it. "
]
} | [] | [] | [
[
"http://arbor.revistas.csic.es/index.php/arbor/article/viewFile/807/814"
]
] |
|
2l5b2l | what is cultural marxism? what does a cultural marxist do? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2l5b2l/eli5_what_is_cultural_marxism_what_does_a/ | {
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"text": [
"A cultural marxists uses what is called critical theory to analyse history, traditions and culture from a marxist perspective. \nMost importantly, they believe that not only it is the upper classes oppressing the lower classes by means of set \"rigged systems\" that keeps the poor poor, but also that traditions and values play a key part in that.\n\nAsk yourself the question \"what is morally right?\" and the answer will likely be affected by the values you have taken from your environment. \nSo what's the point? The cultural marxists try to change culture as a step in changing the economic injustices.\n\nThe easiest comparison I can make is WW1, lots of poor people from different countries killed each other and you can read in many young mens diaries that they were happy and excited over it, partly because of patriotism, and they saw it as morally right.\nFrom a marxist perspective this is the result of cultural \"brainwashing\" since ancient times \nthat the puts the elite in a position were they can spend poor peoples lives to reach their goals and they are compliment.\n\nAlso please note: Nobody calls them self a cultural marxist, that it self is a critical term used by people who don't like it. This is likely part of the reason the OPs votes are going up and down frequently.",
"I have spent a lot of time around activists and college leftist-types, and had never heard this term before coming to reddit and watching it be ascribed to people: First SRS, now anti-GamerGate people.\n\nI know a lot of people who are Marxists, but I know zero people who are \"cultural Marxists\". I'm fairly certain that it is a term that was created to label a group from the outside, that no one actually considers themselves to be.\n\nBecause of this, the term can be defined multiple ways in order to categorize and set aside groups to be maligned. But, and I cannot stress this enough, I don't think there are people who identify as \"cultural Marxists\".",
"Cultural Marxism is a term used by social and economic conservatives to describe liberals and leftists. It is alleged to mean someone who wants to have a more tolerant and degenerate society, but in practice mostly used as a blanket term for \"liberal I disagree with.\" \n\nActual liberals and leftists do not call themselves cultural Marxists, the former because they aren't Marxists and the latter because even if they're one of the Marxist strains of leftist theory, \"cultural Marxist\" doesn't really mean anything.",
"There's no such thing. It's a creation of conspiracy theorists that subscribe to the Frankfurt School conspiracy theory. William S. Lind (noted in regards to the subject at hand for making the ethnic/religious background of Jewish individuals associated with the Institute for Social Research at the Goethe University, also known as the Frankfurt School, an issue) in particular seems to be the driving force behind the creation of the idea of \"cultural marxism.\"\n\nIt's a far, far right wing smear campaign that emerged from the reaction against \"political correctness\" amongst far-right wing circles in the early 1990s. There is no such thing as a cultural marxist. The entire idea that there is a secret cultural marxist plot afoot to take over the world is about as credible as the super secret Jewish plot to take over the world presented in [The Protocols of the Elders of Zion](_URL_0_).",
"the idea that modern consumerist society would be Karl Marx's wet dream"
]
} | [] | [] | [
[],
[],
[],
[
"http://en.wikipedia.org/wiki/The_Protocols_of_the_Elders_of_Zion"
],
[]
] |
||
ox24d | When our bodies burn a gram of fat, protein, or carbohydrates, what percentage of the mass is converted to energy? | What percentage of the stored caloric mass/energy from food or body fat is acutally used as either heat or to perform mechanical work, and what percentage of the mass/energy is excreted as liquid/solid waste and CO2 that we exhale?
Thanks in advance. | askscience | http://www.reddit.com/r/askscience/comments/ox24d/when_our_bodies_burn_a_gram_of_fat_protein_or/ | {
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"text": [
"When we consume food we extract energy from that food but we don't actually convert any mass into energy. Of the food we can metabolize (ignoring things like fiber and salts) more than 90-95% of it is absorbed and metabolized. Of the energy we obtain from metabolism all of it is either converted into heat are used to perform work. enter96 spoke of metabolic efficiency being between 40-60% which is correct. The 40-60% represents the energy used to perform work, the remaining energy is converted to heat.\n\nAll fats and carbohydrates are metabolized into water and carbon dioxide. The carbon dioxide is exhaled and the water (which is insignificant compared to the liquids consumed in any given day) can either be exhaled, sweated, urinated or defecated out of the body. Proteins are also metabolized to water and carbon dioxide, but proteins also contain nitrogen and sulfur which cannot be fully metabolized. Virtually all nitrogen is converted to [urea](_URL_0_) before being excreted in urine. It is noteworthy that the nitrogen in protein could be metabolized further for additional energy but our bodies are unable to catalyze this reaction. I can't say I actually know exactly how sulfur is metabolized but my guess is that it ultimately passes with the feces.",
"A lot of confusion seems to have occured, so I reformulate the question:\n\nIn 1g of fat, protein or carbohydrates, how much energy can be:\n\n1. produced in combustion in pure oxygen, it is the [standard calorie measurement method](_URL_0_) btw\n2. made available to your body, before digestion (before the 1g being digestively broken down, and the body refusing to let some elements into the blood)\n3. made available to your body, if the 1g is already in your system (ie carbs in blood, fat in blood/ in fat cells, proteins in blood/in muscles)"
]
} | [] | [] | [
[
"http://en.wikipedia.org/wiki/Urea"
],
[
"http://www.dummies.com/how-to/content/how-nutritionists-measure-calories.html"
]
] |
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