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e5mdxv | What were some of the other options brought up before settling on the 3/5's Compromise at the Constitution Convention? | I teach 8th grade U.S. History, and I had a student ask "Why didn't the North suggest slaves count as people for representation votes in Congress if slaveowners free their slaves?"
This way, Southerners would have to decide which is more important to them -- representation or the institution of slavery?
Were there other reasonable suggestions before the 3/5's Compromise?
Sorry for a two-pronged question, but were there other reasonable suggestions before settling on the Great Compromise as well? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/e5mdxv/what_were_some_of_the_other_options_brought_up/ | {
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"I'm afraid I can only touch on the Great Compromise a bit, but the 3/5 is in my wheelhouse.\n\nYour student's suggestion was the actual position of the less-enslaving states: enslaved people count zero for representation because they are in essentially no other ways treated like human beings. Counting them for purposes of allocating power, particularly power over white men, would have been illogical, absurd, and morally abhorrent to the white North. The argument was that if enslaved people ought to be counted, then so should livestock. It falls out this way because if representation is contingent on freeing enslaved people, then those people are no longer enslaved and don't count as such...at least as a matter of law. The oft-precarious status of free people of color did not much enter into it. \n\nThe large enslavers, of course, wanted it just the other way: they ought to be able to buy power by buying people. If that meant power flowed directly from enslaving, that was just how things ought to be...though most of them are shy about admitting this at the time. That one's worth and fitness for public office and public life derived almost entirely from one's property value -though also critically from being white and a man- was reasonably uncontroversial. They argued that women and children, and also poor white men, did not have the vote yet they were still to be used for representation. So why not enslaved people? \n\nSo far as the larger dichotomy goes between enslaving people and political power, the white South perceives the two as largely identical. They understand, at least in a nebulous way, that the less-enslaving states to their north have become increasingly hostile to enslaving people. Some of them have already enacted emancipation plans that will, over the course of decades, end slavery within their bounds. That wave of emancipationist feeling might even infect the Upper South (Maryland, Virginia, and company around the Chesapeake at this time) and that would place enslaving in a dangerous position. These fears are always very much overblown, but they're a significant engine of southern politics all through the antebellum. You can get ahead by arguing your opponent is soft on slavery and conjuring an external threat on slavery is the way you build a national coalition in the South among polities that otherwise often disagree. \n\nThus enslaving people needs extra protection, which the white South seeks ardently. This includes protection from democracy, though at the time such a concept isn't seen as inherently problematic since the founders are quite openly authoritarian oligarchs. The extra safety comes in many forms, some of which evolve over time, but the biggest are apportionment in the Senate -which was not *only* because of slavery, but people in the room at the time noted that the issue of small vs. large states rapidly dissolved in favor of division between enslaving and free-r states, with the enslaving very enthusiastic for the Senate as we know it- and the 3/5 ratio. With the sections at rough population parity, or even tilted a bit in the more enslaving states' favor since no one had a national census to work with when the decision was made, those extra representatives mean that the white, enslaving South has a veto on close House votes. The exact value of that is hard to assess -you'd actually have to reapportion the House every time around to know for sure and the method for doing that changed a few times- but it's very much the case that in the great sectional controversies to come that small margin is a factor. \n\nThe third proslavery provision of the Constitution is the one that enslavers were most keen to boast: the fugitive slave clause. In South Carolina's ratifying convention they made it very explicit: until and unless they had the Constitution, enslavers had no right to go into another state to recover a person who dared steal themselves. In essence, they compelled the North to recognize the status of Southern slavery even within Northern jurisdictions. Massachusetts or Pennsylvania might abolish slavery, but only so far as people enslaved in Massachusetts originally were concerned. Should an enslaved person from Virginia escape to either place, the Constitution granted their enslaver a new power to go and seize them back. Quite what that was going to mean was left unclear in Philadelphia, but when it came to legislation on the matter in 1793 -after a controversial rendition case- the white South were not at all ambiguous. They asked for essentially what became law in 1850: a complete legal obligation for men in free states to render aid in the recapture and rendition of enslaved people, practically on the enslaver's say-so. They had to settle for rather less during the Washington years, but still a far more substantive right than the literally nothing they'd had beforehand."
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10ect6 | why germany has maintained economic stability while greece has faltered | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/10ect6/eli5_why_germany_has_maintained_economic/ | {
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"Germany produces a lot of stuff. ",
"I think the answer that terminal_velocity gave has a lot of truth to it; namely Germany has a diverse exporting infrastructure, as well as a controlled import system. \n\nBut the most important thing to remember is that Germany has taxes, okay? Greece in the meanwhile has had huge problems with tax-evasion and under-taxing. [\"With the economy losing as much as $58 billion a year in undeclared income, the administration has made tax collection a priority. But so did previous governments, which failed miserably at the task.\" ](_URL_0_)\n\n**In short, Greece has very little exporting diversity, and horrendous tax policies, while Germany has a fairly rigid tax system and a wide variety of things they sell, that helps them pay for things they need to bring in**",
"Does anyone else think it might not be a coincidence that the northernmost European countries (Norway, UK, Germany etc) seem to be doing fine while the southernmost (Greece, Italy, Spain) all seem to be having troubles? I'm not European, but could geographical culture differences (work ethic, education, traditions etc..) be a factor?",
"Greece didn't falter...Greece didn't have any real economic stability to begin with.\n\nGreece basically lied their way into the EU while the other countries looked the other way, then lied about their finances for the better part of a decade. When things go so bad their couldn't lie any longer, it all fell apart.\n\n"
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vnr2j | Is it possible to kill a house fly with a static charge that you have accumulated? | askscience | http://www.reddit.com/r/askscience/comments/vnr2j/is_it_possible_to_kill_a_house_fly_with_a_static/ | {
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"Well you can accumulate a voltage of between [1000 and 10000 volts](_URL_0_) with static electricity and most electric fly swatters have a voltage of 1500 volts or less, so I would assume it is safe to say that a fly could be killed with a static charge.",
"You're not gonna zap the insect by rubbing your feet on a carpet and touching it in the air, because the fly isn't grounded.",
"It's amperage that kills. I use to do electrostatic painting that used 900,000 volts at micro amperage's. It put out plasma streamers like a plasma ball just without the glass.You could play it on your skin just don't have a good ground when you do. [Here's the Buck Rodgers worthy gun, note the 90KV in the description.](_URL_0_) Yes it is fun as hell to do.",
"Can someone also explain the fastest way to generate static electricity in the normal home?",
"Because the fly is in the air and not grounded, getting current to pass through the fly by a one finger touch is impossible. If you could store the charge in a capicitor and insert electrodes into the fly and touch them to the ends of the capicitor, yes, you could provide a closed circuit current path that would pass through the fly. Whether or not this would be fatal to the fly I am uncertain. While electrostatic discharge can rival stun guns in voltage (100,000 range), the current, or amperage is negligible. Current is what kills, not voltage, though they are related in Ohm's law. Voltage = Current x Resistance. Fun fact- once the human bodies largest resistor is overcome (the skin, people with psoriasis are sky high) by say inputting electrodes through the skin directly into the blood, it only takes 0.1Amps of current to arrest the heart if the current path is across it. If you were to stick sowing needles deep into a finger on each hand and then touch those needles to the ends of a AA battery (~0.13Amps) it would be enough to kill you. It would be an agonizing, slow painful death- DO NOT DO THIS TO ANYONE INCLUDING YOURSELF. ",
"What I'm gathering from the informed discussion so far is that killing a fly with static charge is improbable, correct?"
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83vszh | Nearly half of the people who died from the Spanish Flu of 1918 were 20-to-40 year olds, a normally resistant population. Do we know why? What steps were taken to curb the outbreak (which killed more people than the Great War)? What sort of advances had we made by 1998 to prevent a recurrence? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/83vszh/nearly_half_of_the_people_who_died_from_the/ | {
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"There have been some studies that have shown that people who were exposed to the Russian flu pandemic of 1889-90 were the most likely to die if they contracted the Spanish flu. \n\nExaminations of the virus structure of the Russian flu and Spanish flu have shown that they had vast differences in the structure of their respective viruses. When individuals who had previously contracted the Russian flu contracted the Spanish flu, their immune response was simultaneously delayed and wrong. The individuals' immune systems started producing antibodies based on the Russian flu, but since the virus structure was so different, these antibodies had little to no effect on the Spanish flue. By the time the immune systems realized that the antibodies it was producing was not effective, it was too late. \n\nSource: [Age-specific mortality during the 1918 influenza pandemic: unravelling the mystery of high young adult mortality.](_URL_0_)",
"A common theory related to the Spanish Flu and the generally younger people who succumbed to it is the idea of a \"cytokine storm\" which is to say that an overactive immune system could cause younger people to be more at risk than those with weaker immune systems. \n\nCytokines are small proteins that are used for intracelluar signalling, and in the case of immune response, they are released by immune cells to trigger inflammation. \n\nIn turn, inflammation is a signal to generate more immune cells to fight the issue at the site of the infection and throughout the body. The new immune cells thus release more cytokines and the process continues, but at some point, there is a regulation process which prevents the loop from spiraling out of control. \n\nNevertheless, while cytokines are critical to the immune response, they are also susceptible to becoming unregulated in certain circumstances and this disregulation can cause them to start doing damage. \n\nInflammation is helpful for fighting of disease, but it should be noted that some of the immune cells release toxins that are just as capable of killing normal cells as they are for killing invading cells. Maintaining the immune response for too long, and in too many organs can cause damage which might lead to organ failure and death.\n\nIt is unclear how this disregulation process would specifically work in the case of the flu, and there are other theories, such as the potential for those younger people to be in areas where birds infected with H1N1 were located. Obviously, the war would have concentrated younger people and also caused their movement over long distances to join the war. \n\nWe have had considerable advances that should blunt future influenza outbreaks. \n\nThere is significantly better observation and reporting of influenza outbreaks. \n\nThere are vaccination programs in place. They are not perfect, since you need to get vaccinated against specific strains, but it can be effective.\n\nMedical personnel are also much better trained in general prevention of the transmission of infectious agents. \n\nI'd say that simple reporting, communication, and good practices by professionals would be the most important methods for preventing a pandemic like the 1918 Spanish Flu (which probably started in the United States, BTW). There is some discussion of anti-viral drugs as well, but I don't think anyone is expecting to be counting on those.\n\nLink from NIH that talks about much of the above in somewhat more detail:\n\n_URL_0_\n\n"
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7vo96p | why do our eyes/brains struggle to figure out how many numbers/letters are in something when one repeats it self vs when all are different (12333332 vs 60292813) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7vo96p/eli5_why_do_our_eyesbrains_struggle_to_figure_out/ | {
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"This is because it is easier for the human brain to count different numbers since you can know at which number you are looking at (The criterion is that the next number is visibly different than the previous).\nWhen you have to deal with a repeatitive number, you \"have\" doubts whether you skipped or count twice a number , so you instictively start take more time to make sure you read the number correct."
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1wu3cc | Why did China not discover Australia/ the Pacific Islands? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1wu3cc/why_did_china_not_discover_australia_the_pacific/ | {
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"hi! there's always room for more info on this topic, but FYI, there have been several posts asking about non-European discovery/settlement of Australia. Catch up on previous responses here:\n\nChina\n\n[Why did the British/Europeans discover Australia and not the Chinese?](_URL_5_)\n\n[Why did the Chinese or Japanese apparently never try to colonize Australia or New Zealand? They're right there.](_URL_2_)\n\n[What were some reasons that China turned inwards and neglected maritime exploration after Admiral Zheng He and his missions.](_URL_8_)\n\n[Why were Zheng He's voyages considered wasteful?](_URL_10_)\n\n[How reliable are the accounts for the Chinese explorer, Zheng He.](_URL_12_)\n\nSE Asia\n\n[Are there any evidences for pre-European contact of the Australias?](_URL_0_)\n\n[To what extent did Asian know about the Island of Australia? Are there documents showing the pass of this knowledge to Europeans?](_URL_1_)\n\n[Why did no Asian cultures ever find Australia?](_URL_3_)\n\n[I just read about the Bugis people, the Vikings of Southeast Asia because they discovered Australia and New Guinea long before the European Age of Discovery. What other maritime cultures had a golden era of exploration in the Middle Ages?](_URL_7_)\n\nSouth Pacific\n\n[Why are the aboriginal peoples of Australia and New Zealand so different? Was there much interaction between the two prior to the arrival of Europeans?](_URL_9_)\n\n[Why did the Maori not conquer aboriginal Australia?](_URL_11_)\n\n[Why didn't the Polynesians colonize Australia?](_URL_4_)\n\n[Why did Polynesians stop expanding? Also, why did they never settle Australia?](_URL_6_)"
]
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| []
| [
[
"http://www.reddit.com/r/AskHistorians/comments/1aamc1/are_there_any_evidences_for_preeuropean_contact/",
"http://www.reddit.com/r/AskHistorians/comments/1md46t/to_what_extent_did_asian_know_about_the_island_of/",
"http://www.reddit.com/r/AskHistorians/comments/1jgqt4/why_did_the_chinese_or_japanese_apparently_never/",
"http://www.reddit.com/r/AskHistorians/comments/1na76z/why_did_no_asian_cultures_ever_find_australia/ccgynb6",
"http://www.reddit.com/r/AskHistorians/comments/186f4k/why_didnt_the_polynesians_colonize_australia/",
"http://www.reddit.com/r/AskHistorians/comments/1aq47o/why_did_the_britisheuropeans_discover_australia/",
"http://www.reddit.com/r/AskHistorians/comments/1quk12/why_did_polynesians_stop_expanding_also_why_did/",
"http://www.reddit.com/r/AskHistorians/comments/19g88s/i_just_read_about_the_bugis_people_the_vikings_of/",
"http://www.reddit.com/r/AskHistorians/comments/1a2irc/what_were_some_reasons_that_china_turned_inwards/",
"http://www.reddit.com/r/AskHistorians/comments/1u6uty/why_are_the_aboriginal_peoples_of_australia_and/",
"http://www.reddit.com/r/AskHistorians/comments/1ibdhy/why_were_zheng_hes_voyages_considered_wasteful/",
"http://www.reddit.com/r/AskHistorians/comments/1687hm/why_did_the_maori_not_conquer_aboriginal_australia/",
"http://www.reddit.com/r/AskHistorians/comments/15jt3a/how_reliable_are_the_accounts_for_the_chinese/"
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4n8gv5 | Why were D-Day landing craft designed the way they were? Opening the large ramp from the front seems almost suicidal to me. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4n8gv5/why_were_dday_landing_craft_designed_the_way_they/ | {
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"The D-Day craft to which you are referring (the LCVP) was based heavily on the a boat designed by Andrew Higgins in the prewar years, ostensibly for \"oil workers\" but probably a smugglin' swamp boat during Prohibition. The Marine Corps was not happy with the contemporary Navy options for landing troops on beaches, and so Higgins' design was shoved into production. It underwent a few different versions, the last of which (the LCVP) had modifications based on the earlier Japanese [Daihatsu-class landing vehicle](_URL_0_). The ramp opens front so that troops and vehicles can (ideally) exit onto the shallow part of the beach while the propeller stays in deeper water, enabling the craft to back up and return to the big ships afterwards to pick up another load. If the ramp were to open to the rear, you've got troops and jeeps exiting into 8 feet of water. Yes, when one of these opened into the face of a German MG-42, it was bad, but for every one of those, there were 20 more landing (relatively) safely and unloading cargo and men efficiently.",
"Well, they were designed to function in very shallow water (as aside from being flat-bottomed, ballast could be pumped out as it came into shore so the LCVP sat lighter in the water) so opening the front would cause negligible flooding. [This](_URL_0_) gives you a good idea of how they should function in an ideal situation - with the LCVP's bow-ramp opening above the water. This is aided, of course, by the fact that beaches are generally angling upward!\n\nThe bow-ramp is a good example of Higgins' masterfully economic design: the LCVP's hull was plywood with a steel plate for protection, but the ramp itself was all steel - tough enough to take a pounding from rough seas, hard-packed sand, pebbles or coral, and the love-taps of incoming fire. \n\nObviously conditions could be less than ideal (and there's accounts of the occasional ramp being opened prematurely, jack-knifing the LCVP and flooding it) - the water was choppy and craft were drenched with spray, but as with any modern boat the pumps voided the excess water. Primary sources recall men helping bail out their landing craft with their helmets when the pumps were pushed to capacity (buckets were also available).\n\n**Sources:** *US World War II Amphibious Tactics: Mediterranean & European Theaters* by Gordon L. Rottman and *D-Day, June 6, 1944: The Climactic Battle of World War II* by Stephen E. Ambrose",
"You seem to be treating the single scene from \"Saving Private Ryan\" as evidence that this was how a large number of soldiers died during landings. The scene was put there primarily for effect and not to represent the typical fate of the landing squad. For landing craft to stop directly in front of the gun was just bad luck. \n\nThe idea was to place machine guns in such positions that they would have interlocking fire zones for *sweeping fire* at effective ranges. Sweeping fire was meant to stop the landing forces on the beach and pin them to the ground while they would receive mortar and artillery fire rather than getting killed outright because as deadly as machine guns can be they are not the greatest threat infantry faces in open spaces. That would be HE and fragmentation shells.\n\nThe idea behind an amphibious assault is also that you claim the beachhead by breaking out from the beach and establishing a defensive perimeter. When that happens the beachhead is being loaded up with supplies, vehicles and is the staging ground for further reinforcements, medical facilities etc. As long as you are stuck on the beach forming a beachhead is not possible and you are holding up the landing space for the next wave of troops and vehicles and later supplies. If the troops are kept on the beach then every next wave of landing troops is making the beach a better target for the artillery. \n\nIt is the difficulty in negotiating obstacles, advancing across the beach and the dunes/banks under machine gun and artillery fire rather than getting out of the boats that is the greatest challenge for the landing wave. The greatest threat for the landing force is either getting stuck on the beach and pounded or disembarking too far from the shore and getting hit while still in the water or drowning, losing weapons and supplies etc. Also you might appreciate how important that is when you take into account how difficult running on sand is, and how comparatively harder running in the water is. Then add to it the necessity of running out through an opening along with your platoon without tripping over, falling, losing anything and then sprinting through water, sand, dunes, barbed wire and whatnot towards the nearest cover.\n\nFrom the standpoint of the assault as an amphibious operation it is delivering the troops *as close to shore as possible* and getting back to the main transport ship for more troops *as quickly as possible* that is the main challenge. It is also not as easy as it seems when you have hundreds of ships maneuvering between obstacles.\nThe goal - again - is to get the troops as quickly as possible, brute-force the fortifications and establish a perimeter so that reinforcements, logistical base *on the shore* and preferably light artillery and tanks can get there before a counter attack arrives. For that purpose the bow ramp is actually the optimal solution because save for that rare instance where it opens directly in front of a machine gun nest it allows the LCVP to unload its troops quickly and along the shortest route and then be gone for more.\n\nAll those things considered together the Higgins boat was a great design which proved so successful that nobody really bothered to address the \"death trap\" of bow ramp."
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3e0op2 | how nearsightedness and farsightedness work | How does ones eyes only see objects far away or close up? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3e0op2/eli5_how_nearsightedness_and_farsightedness_work/ | {
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"It has to do with a problem with the lens in your eye. Normally, your lens focuses the light onto the fovea of the retina, which is an area that has a high density of light sensing cells (called photoreceptors). When you are farsighted, light from close up gets focused onto a different part of the retina (not the fovea) and this causes the image to appear blurry. In nearsightedness, light from far away gets focused away from the fovea. \n\nGlasses (and contacts) work by adjusting the light so that it focuses back onto the fovea and the image isn't blurry any more. ",
"With nearsightedness, the eyeball is too long for the lens, so that the image often focuses *in front* of the retina. With farsightedness, the eyeball is too short for the lens, so that the image (if we pretend the retina is transparent) would focus behind the retina. \n\nThe result is that people who are nearsighted can still see things close up, while people who are farsighted can see things far away but not close up.\n\nFarsightedness, which is uncommon, is often confused with presbyopia, which happens with age and is believed to be caused by the lens in the eye getting less elastic, and thus having less focal range. The symptoms are pretty similar, the inability to focus on near things. "
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1oebvs | why are savings account yields in australia 4%/year, and in the u.s. they are .025%/year? | My Sister in law just moved to Australia and she is getting 4% / year compounded monthly where in the states we have a negative real interest rate. Why is this? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1oebvs/why_are_savings_account_yields_in_australia_4year/ | {
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"Because the Australian Federal Reserve bank has a cash target rate of 2.5% - banks charge more than that for lending (I pay 4.9% on my mortgage) and also more than that for certain high interest online bank accounts (the 4% your sister is getting). _URL_0_. Australia has typically had higher interest rates but at the moment we are one of the strongest economies in the world, and if our interest rates were cut much more inflation would be triggered. \n\nThis is distinct from the US interest rate that is 0.25% right now (_URL_1_). \n\nI have Canadian family who talk about sending money here to make better interest. However, the interest earned in an Australian bank account is pre-tax and is counted as income for the purposes of income tax - so if you sent $1,000,000 to your sister (for example) she would have to declare the $40,000 as income subject to tax. So the effective rate is a bit lower. You would also be exposed to the risk that the Australian dollar will sink lower once the US interest rates start to rise again.\n\nI wish I could borrow from the US or Canada on a 30 year fixed rate mortgage, put in a nice futures contract for the foreign exchange risk because I'm pretty sure that would still end up well, well ahead.\n\nTL:DR; Australian economy good, US bad, better economies have higher interest rates all other things being equal."
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5opvys | Limits of the Internet. What is the current limit of possible addresses? | Furthermore with the advent of the IoT. Is there a risk of hitting said limit? What if any are the solutions? | askscience | https://www.reddit.com/r/askscience/comments/5opvys/limits_of_the_internet_what_is_the_current_limit/ | {
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"The most commonly used version of the Internet Protocol (IP), IPv4 uses 32-bit addresses (often represented as 4 numbers between 0 and 255 separated by dots, such as 192.168.1.1). Of these, a maximum of about 4 billion addresses are possible. But due to the way these addresses are assigned, the actual number is much lower. Large parts of the address space are intended for internal networks only and in the early days of the internet, companies were allocated far more addresses than they really needed, which may leave many IPv4 addresses unused.\n\nThere are clearly not enough IPv4 addresses to give a unique address to every internet-capable device. One very common workaround is to use Network Address Translation, which is a technique that allows a number of devices that are on the same network to use a single internet-facing IP address. When you connect to a website on your laptop, that website will probably register the same IP address as when you connect to it on your desktop, tablet or phone that are part of the same home-network.\n\nClever bookkeeping by the router ensures that all traffic coming from the internet into your network is delivered to the correct device, even though multiple devices share the same public IP address.\n\nA more permanent solution is a successor to IPv4, IPv6. In IPv6, the address space is 128 bits, which means there are about 3 * 10^38 possible addresses. This means that every device can be assigned thousands or millions of unique addresses and we'd still not get anywhere close to reaching the limit.\n\nIPv6 is being deployed across the globe, but its rollout is rather slow and we're still having to rely on IPv4 and the workarounds such as NAT."
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2gsmmr | why does it often say when trying to download something "download should start soon, if it does not press this button" instead of triggering the function of the always working button. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2gsmmr/eli5_why_does_it_often_say_when_trying_to/ | {
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"They're trying to load balance server requests so that no one server gets nailed with all of the download bandwidth. They give you the link so that if the fancy load balancer doesn't work you can still get the file from the main server. \n\nAlso ads.",
"Usually the file is mirrored, located on several servers. When you click the initial \"download\"-button, the web-server will query all of its mirrors - asking who is doing the least amount of work at that moment. It will then pick the mirror that can offer you the highest download speed. When you click the \"if the download doesn't start\", it can pick the first mirror, a random one or a separate server.\n\n\nOther times, when you're presented with a countdown. \"Your download will start in 3,2,1 seconds\", they just want ad revenues."
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236vfg | What has the sleep schedule of the US President looked like historically? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/236vfg/what_has_the_sleep_schedule_of_the_us_president/ | {
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"During his presidency Coolidge supposedly would sleep around 11 hours a day. When writer Dorothy Parker was told in 1933 that Coolidge had died she replied, \"How can they tell?\" Source: The American Age: US Foreign Policy at Home and Abroad since 1750, Walter LaFeber"
]
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1ieb04 | What causes pianos to go out of tune, and why do they go out of tune faster if unplayed or in high humidity? | Based on anecdotal and personal experience, pianos seem to go out of tune faster if they're unplayed for long periods of time compared to pianos that see occasional use. This seems counter-intuitive. Furthermore, how does humidity affect the tuning? | askscience | http://www.reddit.com/r/askscience/comments/1ieb04/what_causes_pianos_to_go_out_of_tune_and_why_do/ | {
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"I can answer some of these. A piano goes out of tune when the various components change shape and deform over time. For example, the strings are under quite a lot of tension and will eventually begin to stretch or slip ever so slightly. It doesn't take much of this at all for a good musician to hear the changes. Humidity largely effects the wood of the piano, especially the sound board. Extra humidity can cause the wood to swell which slightly changes the shape of the piano and causes tuning changes. I can't find, nor can I think of why not playing a piano would account for more tuning changes. If I find something I will update you. "
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2if79t | Has there ever been an attempt to create a SI unit of time? | I know seconds, minutes, milliseconds, etc. are SI units now, but has there ever been an attempt to create one more like grams and liters? That is, grounded in some naturalistic value and scaled only by powers of ten? | askscience | http://www.reddit.com/r/askscience/comments/2if79t/has_there_ever_been_an_attempt_to_create_a_si/ | {
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"The second is based on something physical - it's defined as \"the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom\".\n\nIt may seem somewhat arbitrary, because it isn't based on anything fundamental to the universe, but it's no more so than, for example, the kilogram - which is the mass of a cylinder of platinum and iridium held in a vault in Paris. The meter is actually defined in terms of the second, and doesn't have it's own reference point.",
"It is an SI unit, as you say, and it is clearly defined.\n\nThere was a push to decimalize time (use powers of ten) during the French Revolution- when the metric system was introduced. The idea was to divide each day into 10 hours, each hour into 100 minutes, and each minute into 1000 seconds. And I believe the second was broken up as well- if my math is right, it would have been 11.5 times longer than a \"normal\" second. There were also proposals for 10 day weeks and a 10 month year.\n\nIn any case, this never caught on. I imagine the exact reasoning is very complicated. The redefinition of a second (and other units of time) certainly would have taken a transition, though this didn't seem to be a problem for *other* forms of measurement. I suppose that, of all forms of measurement, time is perhaps the most commonly used. \n\nThe other problem with time is that it is already measured for us, in a way. For length of temperature, we can define it in way we like. But we get no say on the length of a day or a year. Considering a year is made up of an awkward number of days, there's no system that can capture time in a fully decimal way. You can use the length of a solar day as the standard and derive seconds from there. But no matter what, you're going to get a disconnect somewhere between days and years. "
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95ylhp | how did manual telephone switchboards work? | Thank you | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/95ylhp/eli5_how_did_manual_telephone_switchboards_work/ | {
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"Your phone (and all phones) were wired to the switching center, where a person would have to manually complete the circuit between the two phones and then manually disconnect when you were done.\n\nLong distance calls required switching at multiple locations, hence the added cost back in the day.",
"In your local switchboard, everyone in the locality who had a house phone had a connection on the switchboard. If you lifted the receiver at your end, at home, a light would illuminate on your connection at the switchboard. \n\nOn the desk in front of the operator, there were two rows of jack connectors sticking out of the desk, plug up [like this](_URL_0_). Each pair one above the other were connected together. That's all they were, like giant aux cables. \n\nAs well as that, for each of those pairs, there was a switch which could be in one of three positions. The middle position just treated the cable like an aux cable, as above, one position let the operator speak to that connection, and the third position made that connection ring. \n\nThe switchboard operator would then plug one of the rear plugs into your lit up socket on the board in front of them to connect them to you, and flip the switch to let them talk to you. They'd ask you where you'd like to be connected to. \n\nIf it was a local number, you'd give them the local number (which would probably be something like \"185\", and then the operator would ask you to wait while they connected you. The operator would then take the other plug sticking out the desk, plug it into the number you'd requested, and then flip the switch to the Ring position. At your end, you'd hear the ring signal, at their end the phone would ring. The operator would wait for the light to illuminate on the connection you're trying to ring, which would tell them they'd picked the phone up, and then the operator would flip the switch back to normal mode, (or if they felt like eavesdropping they could leave the switch in talk and sit there silently listening to the phone call) and you could then talk.\n\nThe operator would know when you'd hung up, because the lights on both connections would go out, at which point she would pull both plugs out and they would reel back into the desk ready for use again. \n\nIf you were calling long distance, there would be some other connections that could be used, called 'trunk lines' which would connect to another switchboard perhaps in another city. Then the operator would connect to one of those, and talk to that operator, to establish an eventual connection between you and whoever you wanted to talk to long distance via these trunk connections. Because this would take time, they would probably tell you to hang up while they established the connection and then ring you back when the call was ready. \n\nAs you can probably begin to imagine, if you were in a busy city, it was quite a fraught job. \n\nAlso, if you ever wondered, the classic old movie trope of rattling the hook switch and shouting \"Operator operator!\" down the phone was actually a thing. Of course, tapping your hook switch would cause your light at the exchange to flash, perhaps increasing the likelihood of the operator connecting to you faster. \n"
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1yuhj0 | The movie zeitgeist | I recently watched the movie and tried to do some research the on the subject of jesus, mithra, dionysus, attis, and maybe a few others (I cant remember). Is there any truth to the claims of the similarities? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1yuhj0/the_movie_zeitgeist/ | {
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"You may be interested in [this section of the FAQ](_URL_1_).\n\nWith Zeitgeist specifically, the answer generally is that no, there's no truth to it. [This](_URL_0_) lists some of them. A few illustrative examples:\n\n1. Horus wasn't born of a virgin, as the movie states, but by Isis impregnating herself with Osiris' penis\n* Horus didn't die, and wasn't resurrected\n* Horus didn't have 12 disciples\n* The film connects Jesus being the 'son' with 'sun' gods, but those two words don't even sound similar in the relevant languages"
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"http://conspiracies.skepticproject.com/articles/zeitgeist/part-one/",
"http://www.reddit.com/r/AskHistorians/wiki/religion#wiki_did_jesus_exist.3F"
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2jupix | Did the original Boy Scouts (British) have a tendency to wander into the army as they got older? What kind of effect did the early Scouts have on patriotism in Britain? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2jupix/did_the_original_boy_scouts_british_have_a/ | {
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"The early Boy Scout movement emerged hand in hand with patriotism in Britain at the beginning of the 20th century. The Boy Scouts creator, Robert Baden-Powell, noted the general despair amongst soldiers during the Boer war in South Africa because of the significant number of casualties in the army. Upon his return to London, Baden-Powell was convinced that reforms in the education of youth were needed. He envisioned a stronger British empire, and one that could rely on physically and mentally strong men. He later wrote in his memoirs that: \n\n*“we had to remedy some of the shortcomings in [soldiers’] character and to fill in the omissions left in their education by developing in them the various attributes needed for making them reliable men. We had to inculcate a good many qualities not enunciated in text-books, such as individual pluck, intelligence, initiative, and spirit of adventure.”*\n\nBy 1917, there were 194,331 Boy Scouts in Great Britain and this number increased to 443,455 over the next twenty years.\n\n**Physical strength** became an early and important feature of the new Boy Scout association. The invasion scare of 1906 and the growing perceived military threat from Germany resulted in an evident shift from social issues to problems and concerns for Britain’s patriotism and citizenship. Physical fitness and good health became national goals. One guidebook maintained that *“to the boy Scout the importance of physical training is very great, for besides being very necessary for his well being, it is also the foundation of the object of that grand Brotherhood to which he belongs.\"*\n\nA strong rhetoric of **imperialism and British strength** over other peoples‘ can be found in Boy Scout guides. In Scouting for Boys, Baden-Powell proclaims that “power at sea has enable us of late years to put a stop to the awful slave trade which used to go on the coast of Africa; it has enabled us to discover new lands for our Empire, and to bring civilization to savages in farthest corners of the world.” History was also rewritten to strengthen this idea. While talking about the Crusades, Baden-Powell asserts that “*scouts cannot do better than follow the example of your forefathers, the Knights, who made the tiny British nation into one of the best and greatest that the world has ever seen.*\" Most historiography on the crusades argues the contrary: economic reasons (knights acquiring land and riches) amongst others fostered the crusades.\n\nScouting evolved into a youth movement that offered a romantic program of outdoor adventures and activities to **remedy the division between classes** and the often disrupted and poor lifestyles caused by industrialization and urbanization. Many British sociologists in the early twentieth century, such as Brian Wilson and William Morrison, saw the increase in violence at the time as the result of the erosion of traditional authority and community control and by the development of adverse living conditions. The Boy Scout Movement acted as a movement in which these divisions could be severed, much like the armed forces in WWI and WWII. Point 4 of the Scout Law states that “A Scout is a Friend to All, and A Brother to Every Other Scout, no Matter to what Social Class the Other Belongs”. By breaking down social barriers, Boy Scouts facilitated the growth of ideas of fairness and parity amongst the British youth. Early on, the movement also established any kind of spiritual commitment (Catholicism, Protestantism, Judaism, etc.) as one of the cornerstones of the movement. A sense of reinforced uniform White racial identity was therefore maintained - one that crossed class and religious lines.\n\nWhen I researched this topic, I wasn't able to find numbers of Boy scouts who became soldiers - I don't know if any survey by the British Armed Forces was done on that subject. *One can only assume that there is a strong correlation*. In any event, the primary and secondary sources I looked at significantly convey the following: the early Boy Scout movement acted as a strong engine to reinforce the ideas of British strength, unity and patriotism.\n\nSources (Primary):\n\nAdams, Morley. *What a Scout Should Know* (London: Henry Frowde, 1915)\n\nLord Baden-Powell of Gillwell. *Lessons From the Varsity of Life* (London: C. Arthur Pearson, 1933)\n \n_____. *Scouting for Boys* (London: C. Arthur Pearson, 1937)\n\n_____. *The Wolf Cub’s Handbook.* Eight Edition. (London: C. Arthur Pearson, 1931)\n\nSources (secondary):\n\nJacobson, Sven. *British and American Scouting and Guiding Terminology* (Stockholm: Stockholm University Press, 1985)\n\nJeal, Tim. *Baden-Powell* (London: Pimlico, 1991)\n\nMacDonald, Robert H. *Reproducing the Middle-class Boy: From Purity to Patriotism in the Boys’ Magazines*, 1892-1914. Journal of Contemporary History. Volume 24, No. 3 (July \t1989), pp. 519-539\n\nParsons, Timothy H. *Race, Resistance, and the Boy Scout Movement in British Colonial America* (Athens: Ohio University Press, 2004)\n\nProctor, Tammy M.*(Uni)Forming Youth: Girl Guides and Boy Scouts in Britain, 1908-1939*. History Workshop Journal. No. 45 (Spring 1988), pp. 103-134\n\nPryke, Sam. *The Popularity of Nationalism in the Early British Boy Scout Movement*. Social History. Volume 23, No. 3 (October 1998), pp. 309-324\n\nReynolds, E. E. *The Scout Movement* (London: Oxford University Press, 1950)\n\nMary Aickin Rothschild. *To Scout or to Guide? The Girl Scout-Boy Scout Controversy, 1912-1941*. A Journal of Women Studies. Volume 6, No. 3 (Autumn 1981), pp. 115-121\n\nWarren, Allen. *Sir Robert Baden-Powell, the Scout Movement and Citizen Training in Britain, 1900-1920.* The English Historical Review. Volume 101, No. 399 (April 1986), pp. 376-398\n\nWilkinson, Paul. *English Youth Movements, 1908-1930.* Journal of Contemporary History. Volume 4, No. 2 (April 1969), p.3-23\n\nZweiniger-Bargielowska, Ina. *Building a British Superman: Physical Culture in Interwar Britain.* Journal of Contemporary History. Volume 41, No. 4 (October 2006), pp. 595-610 "
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1xffbb | Regarding the Large Hadron Collider, what else in terms of the standard model are we still looking out for? Has finding the Higgs made any significant impact? | askscience | http://www.reddit.com/r/askscience/comments/1xffbb/regarding_the_large_hadron_collider_what_else_in/ | {
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"Not much in terms of the standard model. There is still some work going on to determine the spin/parity of the Higgs, and there are always lots of measurements that we can make (production rate\\*, interaction rate\\*, etc).\n\nSM measurements (Higgs coupling, different cross sections, branching ratios, etc) are still incredibly important though, as they will be inputs to searches for new physics beyond the SM (BSM). Also as the LHC upgrades its beam energy, and the amount of uninteresting collisions (called pileup) increases, algorithms need to be tuned and new ones need to be developed. The Higgs will be extremely useful as a benchmark for making sure all our algorithms still work with the higher beam energy. (There will be an entire program for studying Higgs physics at the upgraded LHC.)\n\nNow that we have discovered the Higgs, scientists can really focus on casting a wide net, to eliminate (or validate) as many BSM models as possible. There are way too many topics for me to list them all, but search for things like SUSY, gravitons, dark matter, heavy neutrinos, W' and Z' bosons will certainly be looked at.\n\n*\"Cross section\" is the correct term here. In layman's terms it describes the rate/probability of something happening.",
"There are still some things in the Standard Model that are incomplete or aren't fully understood, such as the strong CP problem or the origin of neutrino mass, but the Higgs was the \"last major piece,\" and the remaining issues are relatively minor in comparison. In other words, with the discovery of the Higgs, all of the broad strokes of the Standard Model have been confirmed to be correct. It is worth pausing for a moment to reflect on how amazing it is that we have literally *correctly predicted* the existence of a *fundamental particle* before it had been observed. In fact, before the Higgs, we knew we were surely on the right track, having already predicted the W+, W-, and Z particles (and their masses) before their discovery. So the Standard Model is clearly a very good model of reality. And now, having confirmed that the Standard Model is broadly correct, the main thing left to do is to simply measure the parameters of the Standard Model to better and better accuracy. We may find that at a certain point some of the predicted parameters deviate slightly from the measured parameters, and this would indicate that the Standard Model is only an approximate model. This is assumed anyways by most people, and indeed another thing that will continued to be searched for are various *extensions* to the Standard Model, such as supersymmetry, that may only be relevant at higher energies than we can currently probe. Thus there is still a desire among physicists to build ever larger particle accelerators like the LHC. There may be more particles/forces out there at higher energies, and we may never know about their existence without being able to produce those energies in the lab.",
"Studying the Higgs that was found at The LHC might give scientists a jumping off point into new physics. WIMPs would interact with the Higgs in some theories, so The LHC could help discover if that is the answer to dark matter. In various supersymmetry theories there are multiple Higgs bosons, and so continuing to explore the properties of the Higgs that was found and further energies could uncover evidence for or against those theories, which could then help with problems like the hierarchy problem or the vaccuum energy problem, which could be related to cosmological expansion ie the dark energy issue. \n\nEdit: I know much of this is past the standard model, but some of the problems like the hiearchy problem are not explained by the standard model from what I understand, so I think the physics community is in agreement that the standard model will get extended or replaced at some point."
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efmziw | Was the father of philosophy Thales of Miletus Greek or Phoenician? | According to Herodotus Thales was from a Phoenician family but many other philosophers imply he's a native of Miletus. Also it's been said Thales' name and his parents names are of Greek and Carian origin.
Can someone clear this up? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/efmziw/was_the_father_of_philosophy_thales_of_miletus/ | {
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"The short answer is: we're not sure, but it's likely Thales came from a Phoenician family that migrated to Miletus. As far as I know, Herodotus is the earliest source we have that talks about Thales. And even this source is written about a hundred years after Thales had already died. So we have very little to base a clear answer to this question.\n\nNow for the more interesting long answer. First it must be mentioned that the Milesians in the time of Thales did not call or consider themselves first and foremost as 'Greek', they would call themselves Milesians first, and Ionians second. At the same time, the people we now call Phoenicians, also never called themselves that. Second, it's important to understand that ethnic categories such as Greek, Phoenician, Carian were in reality not as clear-cut as they seem. The area around Miletus was inhabited since the neolithic, thousands of years before there were Greeks or Phoenicians. Already during the Bronze Age and later Archaic Age, Miletus was a powerful regional city with a rich history. The people who lived there were probably a changing mixture of people we would now call Lydians, Myceneans, Minoans, Carians, Phoenicians, Greeks, ...\n\nSo how can we determine if someone was Greek or Phoenician (keeping in mind that these are categories of a later date and not used by the historical people we're talking about)?\n\nFirst off, language. Miletus was part of the Ionian League. This was a defensive/religious alliance between twelve independent city-states on the western coast of what is now Turkey. They (or at least the elites of these cities) spoke the Ionian dialect of Greek. But even between the cities of the Ionian League there were many differences in dialect. Ionian Greek was also spoken in Athens, and many Ionians had the notion that they were the descendants of Athenians that migrated across the Aegean Sea. But this idea is not to be taken too literal and mostly a result of Athenian expansion in the centuries after Thales. The Athenians tried to expand their power and a semi-legendary common origin was a successful way of making alliances.\n\nThat brings us to population and migrations. The Ionian migration into the region probably occurred around the 11th century BCE. These people presumably came mostly from Attica and Boeotia. The way in which they mingled and lived together with the existing populations is uncertain and most likely happened in different ways each time according to the circumstances. In other instances of Greek migrations we see that they could marry into the local families, they could live together on relatively equal footing, they could go to war and chase off or enslave the people, and everything in between. In whatever way it happened, in these twelve cities, the Greek culture became the dominant culture during the following centuries. \n\nMiletus, like the other city-states of the Ionian League, had a political organisation based on different tribes. It seems there were six tribes. Four of them would have their origin in Greece and two would be local. How large these groups were, or what differences in social standing they had is unfortunately not clearly known. Nevertheless, this shows us that, even though Milesians would later consider themselves Greek (or at least Ionian), their origins are very murky and any idea about ethnic heterogeneity was mostly an ideal not at all reflected in reality.\n\nAbout a century before the birth of Thales, Greek pottery entered a phase called the Orientalizing Period. During this time many cultural influences from the eastern mediterranean entered the Greek speaking communities. It is very likely that a major driving force of these cultural developments were traders and craftsmen who originated in the Phoenician city-states such as Tyre, Sidon, Byblos and had contacts with Greek cities and towns. At first, Phoenician traders would visit and conduct business in these towns (and Miletus was a very important crossroads of the mediterranean trade). Later, these traders would settle down and create small industries and trade hubs. There's no question these traders and craftsmen were at first looked at as foreigners, but they could amass considerable wealth and were probably at times able to secure citizenship and an important place in their new homes.\n\nSo where does that leave us with Thales? If we look at the language, Thales was Greek. For most Greeks, language was the first and most important thing that distinguishes Greeks from barbarians. Since Thales lived in a city dominated and inhabited mostly by people who spoke Ionian Greek, he would have spoken this language as well.\n\nThat Thales was of Phoenician origin, as Herodotus and others mention, is also possible. Lots of Phoenicians spread out across the mediterranean in the centuries before Thales. As traders and craftsmen, some of them were able to become quite rich and secure citizenship and prominent places in the societies they migrated to. That Thales is a descendent of Phoenician migrants is therefore perfectly imaginable.\n\nIn conclusion: was Thales Greek of Phoenician? The answer is most likely: both, with countless caveats about the complexity of ancient ethnicity and identity.\n\nMain sources:\n\nRoebuck, C. 'Tribal Organization in Ionia' (1961).\n\nGreaves, A. M. 'The Land of Ionia' (2010).\n\nAnd of course the Histories of Herodotus."
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3fg0tv | What am I missing in Einstein theory of relativity? | I am currently reading Walter Isaacson's biography of Einstein. I am going to paraphrase this example he cites Einstein as using to explain relativity:
Two people are at a train station a certain distance way from each other. Lightning strikes, and the person close to the middle of the two lightning strikes perceives them as happening at the same time. The other individual is closer to one of the lightning strikes, and perceives that that one happened slightly before the other one because he was closer to it, giving the light less time to travel to him. If I understand right, this argument was used to show how things are relative, and what we perceive as time is dependent on different factors.
My confusion is that even if they perceive things differently, that doesn't change the fact that one of the lightning strikes did indeed happen first, right?
I came up with my own thought experiment to demonstrate my point. A man is standing 50 meters away from a man shooting a gun, and 1,000 meters away from another person shooting a gun. The man 1,000 meters away shoots his weapon, and directly after the individual 50 meters away fires. Our test subject would insist that the man 50 meters away fired first, since it would take the sound of the individual 1,000 meters away longer to get to him, warping our test subjects chronology of events. This doesn't change the fact that the one further away actually fired first, though.
I think I might be totally off base in understanding this principle, and help is appreciated! | askscience | http://www.reddit.com/r/askscience/comments/3fg0tv/what_am_i_missing_in_einstein_theory_of_relativity/ | {
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"If that is the example in the biography used to explain how simultaneity of events is relative, then it is not only a terrible example, but it just entirely misses the point of relativity.\n\nIn the example, the two observers are not moving with respect to each other. So they are in the same inertial frame. This means that the same event gets the *same* temporal coordinate from both of them. In other words, they should both say that the two lightning strikes hit at the same time. The author of the example is confusing two very different concepts: coordinates of events and human perception of events. It is certainly true that the individual standing closer to one of the strikes literally sees with his eyes the arrival of one flash before the other. But that is not what is meant by relative simultaneity.\n\nThis confusion is actually more common than I would hope, simply because we typically use words like \"observe\" and \"see\" to talk about spacetime coordinates, and not to imply anything about actual human perception. Human vision is not based on spacetime coordinates, but rather the simultaneous arrival of photons at our eyes. \n\nThe relativity of simultaneity only occurs when we talk about observers in *different inertial frames*. That is, the two individuals should be moving at constant velocity with respect to each other. Before relativity was discovered, simultaneity was still absolute for all inertial observers. Every observer assigned the same temporal coordinate to same event, regardless of whether they were in motion with respect to each other. In relativity, that simply does not happen. Observers moving with respect to each other will assign different temporal coordinates to the same event, and this is very non-intuitive given our typical (human) perception of the world.\n\nYour example of the three men shooting guns is correct. All three men are not moving with respect to each other. So they should all give the same time for the two shootings.",
"That example isn't very good for reasons someone else already answered, but I'll reply to this part:\n\n > My confusion is that even if they perceive things differently, that doesn't change the fact that one of the lightning strikes did indeed happen first, right?\n\n\nConsider the difference between these two statements: \"The car is to the east of the house\" and \"The car is to the right of the house\". In the first case, you can grab a compass and check. In the second one, there is no possible experiment you can do to say whether or not it's really true. What would it even mean to be really true?\n\nEveryone disagreeing doesn't imply that it's like the second case where there's no objective truth, but it certainly suggests the possibility.",
"I think you may have misremembered the example, since it would have likely placed one observer on a moving train and one on the platform, as so:\n\n_URL_0_\n\nAs the video shows, it's not about \"I saw this happen first, so it happened first.\" It's about \"I saw this happen first, and I know the speed of light, so I can do math to figure out exactly when that event happened.\" \n\nSo for your gun shooting example, everyone would agree on the timing of events because the observer knows how long it takes sound to travel 1000 meters and can do the math to figure out when the gun fired.\n\nWhen you put people in different reference frames, however, they will no longer agree on the exact timing of events. They may even disagree on the order of events. Again, they are doing the math to figure out when events happen, and not just saying \"I saw it first so it happened first\" without regard to their distance from the event."
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eky3te | What were the reasons the U.S. attempted to pull off a coup of the Iranian government in the 50s and eventually imposed the Shah? | It's my understanding that the U.K. was upset that the Iranian government had nationalized their oil industry and asked the U.S. for help. Iran had been getting a pretty terrible deal from the U.K. and was just trying to take back control of it's natural resources. I thought the Iranian public had a very positive view of the U.S. at the time and this started off a chain of events that led the very hostile relationship we currently have. Why did the U.S. think this was a good idea? Why did the U.K. go so far with this even though what Iran did was within it's rights/power as an independent nation? Why did the U.K. decide to ask the U.S. to do this for them? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/eky3te/what_were_the_reasons_the_us_attempted_to_pull/ | {
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"This is a complex topic but I'll give it my best stab!\n\n > I thought the Iranian public had a very positive view of the U.S. at the time and this started off a chain of events that led the very hostile relationship we currently have\n\nFirstly, you're correct that the Iranian public had a relatively positive view of the US but I'd be careful of suggesting that the coup \"started off a chain of events that led the very hostile relationship we currently have\". This can present an overly inevitable view of history; people are quick to link the coup to the Islamic Revolution but do bear in mind that they're more than 25 years apart and plenty could have gone differently in that time.\n\nBut to get to your main question, the UK and US both have several important motivations which different historians give different weight. I will separate them roughly into economy, strategy, ideology.\n\n**Economy**\n\nIt is hard to overstate the value of the Anglo-Iranian Oil Company for Britain here; it is Britain's single largest overseas asset at a time where the country is trying to rebuild itself from World War 2. It is a vital source of dollars in a very literal sense given Britain's balance of payments woes at this time.\n\nBeyond this, they were not the only player that stood to gain economically from the coup. The US had been frustrated by Britain's restrictive control on Iranian oil which denied US oil companies market access; following the coup this arrangement was clearly unsustainable and US companies were able to enter the market much to their benefit.\n\n**Strategy**\n\nAs the British Empire was increasingly called into question, British strategists increasingly turned towards Africa and the Middle East as a solution to secure Britain's global position. The Anglo-Iranian Oil Company is not only a key resource: it's a key aspect of British strategic influence in the region (along with the Suez canal). For an easy example, just consider the importance of a secure oil supply through the major wars that had just passed.\n\nBritain's strategic position is also a concern for the US. The US and the UK have just come out of WW2 where they fought as allies. They didn't always see perfectly eye to eye, but nonetheless they had an important strategic relationship. This especially true as the Cold War Era commences and the US is increasingly concerned with the spread of communism.\n\n**Ideology**\n\nThe Iranian Oil Crisis is fascinating for the way which it highlights the balance between different ideological paradigms: imperialism, nationalism, and \"cold-war\"ism.\n\nYou've asked why the UK pursued the coup even though Iran was acting within its rights as an independent nation. This reflects a modern conception of nationalism -- and one which Iranian nationalists were quick to uphold -- but which wasn't necessarily that convincing to the British imperialist mindset. At least not when vital resources were on the line. \n\nFor the US, the ideological confrontation with the USSR -- and the possible spread of communism -- was a growing concern. Mosaddeq had wide popular support and something of a socialist platform. He also unfortunately also played to US fears of Iran falling to communism in an attempt to gain aid from the US; some later American sources further suggest that the British deliberately played on this fear to push the US into action. It's difficult to know exactly how much weight to give the fear of communism since naturally its a nicer justification for the Americans involved than oil-money. One thing that I would highlight here is the distinction between the Truman and Eisenhower administrations. Under Truman the US takes a generally reconciliatory approach with significant efforts towards a negotiated settlement. Eisenhower's administration (which is generally further into the paranoia of the Cold War) takes office and the coup follows shortly after. \n\nRegarding why the UK asked the US for help, on top of the close economic and strategic relationship above there is also an important practical factor: the UK's ability to orchestrate a coup is hampered after Mosaddeq expelled Britain's diplomatic mission in 1952 and working with the CIA helps them to overcome this obstacle.\n\n**Closing thoughts**\n\nFirstly, I have separated various factors out, but please don't read them in isolation. For example, Iran's strategic importance should *also* be read in terms of the post-war geopolitcal orientation towards Cold-War competition between the US and USSR, and the American desire to open the Iranian oil market has an ideological undercurrent as well as an economic rationale. \n\nLastly, I do want to re-iterate that this is a really fascinating question which remains debated in the historical community. Over-emphasising the \"fear of communism\" interpretation risks giving too much weight to post-hoc explanations given by Americans and arguably verges on apologia. (This is also complicated by the fact that detailed American sources were more readily available than others). At the same time, over-emphasising the \"it's all about money and power\" interpretation risks boiling complex ideological and personal factors down to simplistic realpolitik. An interesting questions to ask yourself as you delve into the topic is \"why does the US behave differently around the Suez crisis only three years later?\".\n\nMain sources:\n\nGasiorowski and Byrne (Ed.), *Mohammad Mosaddeq and the 1953 Coup in Iran* \nKatouzian, *Musaddiq and the Struggle for Power in Iran* \nLouis, *The British Empire in the Middle East, 1945-1951* \nBill and Louis (Ed.), *Musaddiq, Iranian Nationalism, and Oil* \nGalpern, *Money, Oil, and Empire in the Middle East: Sterling And Postwar Imperialism, 1944–1971*\n\nFor more accessible reading, I recommend Gaziorowski, ['Coup d'etat of 1953'](_URL_0_) in the *Encyclopaedia Iranica* which is an incredible peer-reviewed online resource for Iranian history."
]
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"http://www.iranicaonline.org/articles/coup-detat-1953"
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1dypz7 | If someone was hemorrhaging uncontrollably, could you keep them alive by transfusing blood in at the same rate they were losing it? | That is, if someone had a life threatening hemorrhage out of a major artery, if you did nothing to control the bleeding, but transfused whole blood in at the same rate they were losing it, would that person survive? Could they have their entire blood volume replaced and survive? | askscience | http://www.reddit.com/r/askscience/comments/1dypz7/if_someone_was_hemorrhaging_uncontrollably_could/ | {
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"People can certainly have more than their entire blood volume replaced and survive. Normal blood volume is around 70ml/kg, so about 5L on average. One unit of blood (packed red cells) is around 250ml, so once someone has received more than 20 units of blood they are close to having replaced their circulating volume. Transfusions of this amount are certainly not uncommon, and I have seen people who have received 50 or even 100 units of blood survive.\n\nThere are significant problems with giving this amount of blood though. You mentioned whole blood in your comment, and that would certainly be ideal. Most blood banks don't store whole blood though; donated blood is separated into its components parts, such as red cells and plasma. Blood is normally given as packed red cells which doesn't have the plasma component. This is important as its the plasma which contains the proteins you need to allow blood to clot.\n\nSo, as you transfuse large amounts of packed red cells into a bleeding patient the coagulation factor are lost (this is called dilutional coaguloapthy) and the patient won't stop bleeding. Its therefore important to transfuse plasma and concentrated clotting factors as well.\n\nOther problems from massive transfusions are hypothermia, as these products have been stored in freezers, so are cold, and metabolic problems from the additives in the blood packs, Citrate, for example is used to prevent the blood from clotting in the pack, but in large amounts can lower calcium levels and cause alkalosis.\n\nLarge volumes of blood can also cause fluid overload and can specifically damage the lungs, a condition called TRALI (Transfusion Related Acute Lung Injury)\n\nCurrent research into this topic is looking at how much plasma you should give per unit of blood (it looks like we haven't been giving enough in the past) and whether the age of the blood matters; it seems like the longer the blood has been stored for, the less beneficial it is."
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445wzb | Do all plants metabolize (convert CO2 to O2) at the same rate or do some plants generate O2 more efficiently than others? | I'm wondering if some plants can generate more oxygen with less sunlight, or if crating sugars faster than other plants would yield more oxygen. | askscience | https://www.reddit.com/r/askscience/comments/445wzb/do_all_plants_metabolize_convert_co2_to_o2_at_the/ | {
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"There's variation among plants generally, but specifically an alternative carbon fixation pathway called Crassulacean Acid Metabolism (CAM) used in plants that are found in arid climates that is less efficient, but with the benefit that it allows the plant to shutdown respiration during the day when heat and dry air pose a threat of substantial water loss.",
"I did a little extra digging and might have answered my own question. So if anyone else is wondering, here is a [wiki article](_URL_0_) about genetically modifying RuBisCo enzymes to improve photosynthetic abilities."
]
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"https://en.wikipedia.org/wiki/RuBisCO#Genetic_engineering"
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acj8mw | scientifically speaking, is there a hypothetical cure for every disease? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/acj8mw/eli5_scientifically_speaking_is_there_a/ | {
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"the short answer is that we don't know.\n\nWe've cured a lot of diseases and accomplished amazing things with science. at times it seems that everything is possible. But unless we cure ever disease, we won't really know. \n\nMy guess would be yes. But we can really only guess.",
"_Hypothetically_, yes. All a disease is is the malfunctioning of a biological process. If a process works correctly, then something happens to cause it to malfunction, it is theoretically possible to correct the malfunction and restore the process to working order.\n\nHowever, _how_ one does that is the tricky part. "
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6hmn3m | what does the 'end task' command do differently than normally exiting out of a program? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6hmn3m/eli5_what_does_the_end_task_command_do/ | {
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"Imagine you are in a restaurant. And then you're asked to leave. You pick up your shit and leave. That's closing a program normally. Now when you end task. They bring in some bouncers and kick your ass out before you get to pick up any of your shit.",
"Programs usually have various operations to do before they shutdown. If a program is frozen, it is unable to perform/finish these operations, and does not shutdown. 'End Task' closes it regardless.",
"There are three main ways to stop a program. \n\nYou can quit from inside the program. The program does whatever it's programmed to do when you click quit, saving data and closing files and such normally.\n\nYou can use End Task (on windows), this is the operating system sending a signal to the program that tells the program \"Time to quit, finish what you're doing and then exit.\". The program (hopefully) responds to the signal, finishes up what it's doing, saves data and such, then quits.\n\nYou can use End Process (also Windows). Windows just ends the program, and frees up any memory associated with it. There's no communication with the program.\n\nIn terms of the other guy's restaurant metaphor: Quitting is finishing your meal then paying up and leaving, end task is being told to pack your shit and leave, and end process is being thrown out. ",
"One of the main parts of a desktop application is called the \"message loop.\" It is code that continually runs, checking for new messages from the operating system or other programs. Messages include things like user input (you clicked a mouse or pressed a key) as well as other notifications that an application is supposed to respond to.\n\nOne of the messages that you can receive is the Quit message. This is how the operating system tells an application that it should shut down. The application should respond to this message by trying to exit in as graceful a manner as possible - for example, giving the user a chance to save any unsaved work. This is generally the same flow as normally exiting out of the application.\n\nSelecting \"End Task\" from the Task Manager in Windows sends a quit message to the application and then relies on the application shutting itself down. Because it's up to the application to handle this, there is a valid response which is \"No.\" For example, if you have an unsaved document the application might ask for confirmation if you want to quit and you could click no. So the OS does not actually enforce that the quit message results in the application terminating.\n\nHowever, if the application is in a bad state this message might not ever be received, or the application could still fail to shut itself down. In that case, the operating system can terminate the program by simply not running its code any more and unloading all of its code and data from memory, as well as cleaning up any shared resources it was using such as files or network ports. This means any saved work will be lost so it is the method of last resort. The OS will generally ask you if you want to terminate a process in this way if the message loop stops running for an extended period of time.\n\n",
"I've always heard it explained this way. Closing a program normally is akin to being in your car driving down the interstate @ 70MPH, taking the off ramp, braking slowly, coming to a complete stop, shutting the engine off and exiting the vehicle. \nEnding the task is like having someone throw a cinder block through the windshield while driving @ 70MPH. "
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6fp08l | how someone can have a big belly but is relatively skinny/normal? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6fp08l/eli5_how_someone_can_have_a_big_belly_but_is/ | {
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"Fat deposits vary from person to person and from source to source. A few of the hormones racing through your body affect the location of fat (cortisol directs it to the abdomen, for example) as well as your sex. (Women tend to have a 'donut' or bigger legs, men tend to have bigger bellies.) I don't know enough on the subject to give you a specific answer, sadly. On the bright side; as long as it's hanging in front or on the side of you, the dangers are relatively low. Fat between the organs or 'hard fat' is where you need to be scared.",
"In some cases this could be a sign of an underlying illness, such as celiac disease (which can cause a bloated belly on a skinny person). As to other cases, I can't say.",
"A swollen abdomen is also a sign of malnutrition. The boy needs to make proteins to circulate in the blood or osmosis pulls the water out of it, typically expanding the abdomen as it isn't constrained by bones like the chest or head.",
"Sometimes it can be caused by alcoholism causing a swollen liver although that looks a little different because the \"belly\" might seem a little high and off center."
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4i0a08 | why does windows 10 take over 2 gb of ram to sit there doing nothing, while windows 95 needed less than 0.004 gb? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4i0a08/eli5_why_does_windows_10_take_over_2_gb_of_ram_to/ | {
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"1. It's not sitting there doing nothing. There's tons of stuff running in the background- updaters, anti-virus, Cortana, and more.\n\n2. It doesn't actually need a full 2GB. But RAM that's not being used is just wasted, so it will load extra things into memory to speed up the computer if you have more RAM than you need.",
"If you have RAM that you aren't using then Windows 10 will 'preload' things that you use a lot. That way when you actually go to use them it doesn't have to waste time to load it. It tends to make the OS more responsive for things that you do on a regular basis. "
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33iigz | does the united states government heavily regulate media outlets? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/33iigz/eli5_does_the_united_states_government_heavily/ | {
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"No. The concept of [prior restraint](_URL_0_) is almost completely foreign to the US legal system.\n\nNow, the government can always *ask* an outlet not to run a story, or at least to delay it, and sometimes the network or newspaper will oblige. But it's almost impossible to legally prevent a US newspaper or television network from releasing any information at all."
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e64kn2 | what is a name server, what is a network domain, and how are the two related? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/e64kn2/eli5_what_is_a_name_server_what_is_a_network/ | {
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"So a name server is like a telephone book, it takes the name of a website and converts that information into a usable IP address which is an internet protocol series of numbers like 8.8.8.8 which is used in this case to connect to _URL_0_",
"Sorry if this gets rambly; I'm at the stage where I intuitively know what these things are, but explaining them in ways that make some amount of sense is challenging.\n\nDomains are an abstraction that tells us what groups of computers have some degree of connectivity to each other. The form of this that most people will be familiar with is your standard corporate or education network; on a hardware level you have one or more main lines out to the outside world, and these have routers in front of them; then the routers connect to special servers called *Domain Controllers* that handle functions like IP address assignments and authentication and holding an authoritative directory of computers and users on the network. If you're hired by a new place and they give you some form of a \"corporate login\" then they're probably adding a user account for you on some sort of domain controller.\n\nThe domain generally has a name, and some networks can have multiple domains that may or may not be able to see each other, but (importantly) the IP assignments and authentication from other domains won't work there. \n\nAnother place we don't think about domains, are the sites we use daily. _URL_2_ is what's called the *domain name* for a site that is open to the entire internet, and every server in the Reddit domain is under this hierarchy.\n\nName servers, or Domain Name Servers, have a particular function that is most evident when talking about domains like _URL_0_: making your computer know where you want to go when you type \"_URL_0_\" into your browser. At the most basic level it's a huge table with one side being the network address of the computer, and the right side being the \"friendly\" name that humans can remember. This happened because, funnily enough, most people didn't want to keep a list of IP addresses for their favorite websites, and companies who wanted to use websites for marketing purposes found that it was much easier getting people to visit a site like \"_URL_1_\" than \"66.248.19.154\" for instance (note: no idea where that IP leads, investigate at your own risk)\n\nBack to your work domain, this gets used if your work has specific sites like a work intranet page with internal tools for your job, or even just an online company newsletter; in this case anyone on the domain for, say, widgets inc, can put \"widgetnet\" into a browser and get to the internal widgetnet page, or say \"payroll\" for HR to be taken to the server that hosts the payroll software; these are very customizable and (importantly) not routable from the internet in general; you generally have to be inside that domain to access it.\n\nHopefully that's a somewhat decent explanation."
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"Reddit.com"
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1r9av2 | how can long water fasting periods be healthy? | My best friend Is overwieght and has been fasting for four days but he plans on going for fourty days in total. How can this be healthy? Should I encourage him to rethink things? A person needs to eat right? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1r9av2/eli5_how_can_long_water_fasting_periods_be_healthy/ | {
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"That is insanely unhealthy. I had a friend one time do a 40 day fast, did it more for some personal factors, not weight loss. He discussed it with his doctor and took the proper precautions and he did it.\n\nFasting should **never** be a method of weight loss. His obesity will simply complicate things... Terrible idea. ",
"It's not healthy at all. In fact, it's often lethal. ",
"First off, fasting is an absolutely terrible way to lose weight. Your body actually takes the lack of food as a signal of danger and makes your body burn less in order to sustain itself longer.\n\nWater fasting may seem to make someone lose weight, but they're just losing water weight and nothing else."
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1c5doq | How dependent is oceanic life on phytoplankton? Not just fish, but mammals and all life forms that live off or in the ocean? | If there were a virus that drastically lowered the amount of, or killed all the phytoplankton , is there any animal that we commonly associate with ocean life that would not lose their food chain, or even thrive? | askscience | http://www.reddit.com/r/askscience/comments/1c5doq/how_dependent_is_oceanic_life_on_phytoplankton/ | {
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"[Extremeophiles](_URL_0_) would be okay."
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| []
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"http://en.wikipedia.org/wiki/Extremophile"
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5qufpa | why us telecos still use cdma technology, when majority of the world uses gsm for the communication? | What's benefit of using CDMA in the US ? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5qufpa/eli5_why_us_telecos_still_use_cdma_technology/ | {
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"The main reasons are a matter of timing, corporate greed and legacy.\n\nBack when the US networks where starting to form, the switch from analogue to digital cellular technology was also happening and CDMA had some interesting advantages over GSM.\n\nOne of the most appealing features at the time (And still continues to be) was that it is easier to lock a CDMA user into the network that provides the phone than it is with GSM technology whose spec demands that they be interoperable between networks. CDMA makes it harder for a user to leave a network for another one and take the phone with them (In some cases it's impossible).\n\nThere where other benefits to CDMA as well such as greater capacity on the network, a questionable theory that call quality was better and so forth but GSM caught up very quickly and eventually leapfrogged CDMA in the quality and feature departments.\n\nNow of course, some of those network operators have folded into the big players you see today and frankly switching from CDMA to GSM is a BIG commitment those network operators don't really wish to undertake.\n\nCDMA as a technology outside of the USA and small parts of Russia is dead with the advent of 4G. GSM has been taken up by most of the world, mostly driven by Europe's mass uptake of it. Though 3G briefly was based on a variance of CDMA, 4G uses a technology called LTE which is a further refinement of GSM technology.",
"The selection of CDMA over GSM was mostly based on the distances and number of users supported by an antenna. CDMA was initially superior to GSM on both, therefore cellular networks could have better coverage with fewer macro cells (towers). However with the adoption of LTE, as well as refinements to 4G over GSM (contrary to popular belief, modifications to both CDMA and GSM were allowed to call themselves 4G without supporting LTE), and subsequent future migration to 5G, the differences have become moot.\n\nBut as the US was an early adopter of cellular technology, and Qualcomm was the leading provider of CDMA technology to both Verizon's predecessors and cell phone manufacturers."
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xaiu9 | Jesus Christ and John the Baptist - Bibical Scholars wanted | A while back, I remember reading a theory (might have even been on r/AskHistorians) that Jesus was a disciple of John the Baptist or a member of a cult (or whatever the proper terminology is) led by him and that much of the doctrine passed down by Jesus originated with that man. I remember him using textual evidence from the bible to support this claim. I am pretty ignorant of the Bible in general, and I was wondering of anyone else had heard of this claim and knew the arguments used to support it, as well as any flaws in those arguments. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/xaiu9/jesus_christ_and_john_the_baptist_bibical/ | {
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"The association of Jesus with John is more or less universally accepted. There are a number of clues.\n\nFirst is the baptism. John offered baptism for the remission of sin, a fact that caused the last three evangelists apparent embarrassment. Matthew and Luke have John denigrate himself at the event. John goes a step farther and eliminated the baptism entirely. Why make it up if it causes problems?\n\nAgainst this view we should bear in mind that the earliest known recension, that of Mark, shows no such shame.\n\nThe second is that all four evangelists are careful to have John either implicitly (such as his emissaries from prison) or explicitly acknowledge Jesus as the Messiah. This seems to indicate that such an endorsement was important to the early Christian movement.\n\nAdditionally, the idea of baptism for remission of sin is unattested in judaism prior to John. Both the capacity of immersion to serve in this way and the idea that such an act could be performed by a third party are novelties, shared by the Baptist and the Christian movement.",
"So far as I know, one of the the most well-known versions of this theory comes from E. P. Sanders:\n\n > Two of the things which are most securely known about Jesus are the beginning and the outcome of his career, and these are also two illuminating facts. Jesus began his public work, as far as we have any information at all about it, in close connection with John the Baptist, probably as a disciple.\n\n[E. P. Sanders, *Jesus and Judaism* \\(Minneapolis: Fortress, 1985), 91.](_URL_1_)\n\nSanders is not the only scholar to hold this opinion, nor does every scholar in the field agree with Sanders. See [Max Aplin's Ph.D. dissertation, \"Was Jesus Ever a Disciple of John the Baptist? A Historical Study,\"](_URL_0_) pp. 39-42, for a list of scholars on all sides of the argument."
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"http://books.google.com/books?id=Ng9JaKKaeCIC&lpg=PP1&dq=e%20p%20sanders%20jesus%20and%20judaism&pg=PA91#v=onepage&q&f=false"
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5rk0bm | what is the difference between relative humidity and dew point? | What is relative humidity and dew point?
What is the differences?
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5rk0bm/eli5_what_is_the_difference_between_relative/ | {
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"They are related in that they are both measures of the amount of water in the air.\n\nRelative humidity compares how much water vapor is in the air to how much water vapor the air could possibly hold at the current temperature. It is a measure of how saturated the air is compared to how saturated it could be.\n\nDew point is the temperature at which the current amount of water vapor in the air would be the maximum amount. Since as the air temperature cools, it can hold less water vapor, there is a temperature where the air can no longer hold the water vapor it currently has. That's the dew point."
]
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4jd20l | How did the Roman aristocracy treat/view plebeians? Were they treated differently at different points in the republic? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4jd20l/how_did_the_roman_aristocracy_treatview_plebeians/ | {
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"Much of the historical narrative that we have for the early Republic is dominated by the so-called struggle of the orders. This was sort of a civil rights campaign by the plebeians for equal rights. At this stage the patricians were a handful of established aristocratic families, and the plebeians were everyone else. At first, the patricians monopolised all the major political and religious offices, but the plebeians gradually won the right to hold these positions. One of the most important victories for the plebeian cause came in 367 BC, when a law was passed guaranteeing at least one plebeian consul; subsequently more and more offices were opened up to plebeians. (It should be noted that the literary sources we have for this period are much later, and are therefore open to question. But we don't have anything better to go on, so most historians tend to assume that the surviving narratives are based on a factual core even if many of the details are invented or distorted.)\n\nBy the late Republic, the patrician-plebeian distinction was largely redundant. There were still patrician families, but these were not synonymous with the office-holding nobility, as they had once been. Being a patrician could even be seen as a disadvantage: one patrician, the populist politician Publius Claudius Pulcher (wow, alliteration), had to be adopted into a plebeian family in order to stand for the office of tribune (he became Publius *Clodius* Pulcher in 59 BC as a result). In late Republican parlance, \"plebs\" became a more general term to refer to the common people, meaning anyone who didn't belong to the senatorial or equestrian classes, except in technical cases like that of Clodius."
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3sgu4l | why are governments post-actively banning the filming of slaughter house cruelty instead of pro-actively following animal abuse laws? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3sgu4l/eli5_why_are_governments_postactively_banning_the/ | {
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"I don't know where the government is specifically making it illegal to film that - it already is based on normal privacy and employment law. If you trespass onto a private property to film, that's illegal. And if you gain employment there to film secretly, you've committed fraud - and you've probably violated a clause in the employment contract you signed. \n\nA USDA Inspector has to be present at all times a slaughterhouse is operating. However, the agency is massively underfunded given the size of the industry, and they have a shortage of inspectors. If the abuse happens where the inspector doesn't see it, and it doesn't affect the meat after slaughter, it's not going to be noticed. And those videos, horrific as they may be, are illegally obtained by private individuals with no way of verifying their authenticity, so they wouldn't be admissible in any type of legal action.\n\nAlso, if a violation was observed, I believe it would be handled as a regulatory issue, unless it became a repeat or widespread violation, or seriously affected the safety of the meat. The company would be issued with a finding and be given a time period to show that they had corrected. (I'm more familiar with FDA procedure than USDA, but I assume it would be similar.) So, if there are cases where violations were found and corrected, you'd be unlikely to hear about them."
]
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1qfqto | Can anyone recommend any books or articles on ancient cultures and sharks? | How they interacted with them, utilized them, regarded them or generally what type of knowledge did these cultures have of them. I'm really interested in how our collective knowledge of sharks grew and haven't been able to find much online other than historical accounts of encounters. Thanks for any help. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1qfqto/can_anyone_recommend_any_books_or_articles_on/ | {
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"This article might not quite fit the bill -- it's not specifically situated in an ancient period -- but it does do a good job of exploring the place of sharks in Hawaiian religion and culture.\n\nGoldberg-Hiller, Jonathan, and Noenoe K. Silva. “Sharks and Pigs: Animating Hawaiian Sovereignty against the Anthropological Machine.” South Atlantic Quarterly 110, no. 2 (Spring 2011).\n"
]
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77y8tw | how do recycling plants process liquids? | Like if a water bottle still has some water in it, or a soda can still has some soda in it. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/77y8tw/eli5_how_do_recycling_plants_process_liquids/ | {
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"Yay! Something I can finally answer! \nI work as a chemist at a waste disposal facility. At our plant we sort liquids into various catergories depending on what we think is in the containers.\n\nThese containers are then shipped off to a machine which essentially crushes all the liquid out of the containers making cubes of plastic or metal. \n\nThe liquid itself is gathered in large 1000L drums and shipped off to another facility to be chemically treated to be safe for release into the environment.\n\nIf this can't be achieved the liquid gets incinerated in small batches. \n\nHope this helped! ",
"I think your question has been answered, but there's also cool machines that use lasers to estimate the amount of liquid and determine what type of material each container is, then blasts air jets to sort each type off the conveyor belt into different streams. \n\n[Here's a crappy video I found of something like this.](_URL_0_)"
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6vuxyw | why do we feel the weird banging in our body when listening to loud live music | When the music (mostly at the concerts) is loud, I feel like the music vibration is shaking my lungs and heart. What is that? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6vuxyw/eli5_why_do_we_feel_the_weird_banging_in_our_body/ | {
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"Sound is pressure waves moving through the air that vibrate your eardrums.\n\nYour ribcage doesn't have much that is solid behind it to stop it vibrating to large, low frquency pressure waves.",
"Sound is just waves of pressure or vibrations moving through a medium like air. What you're feeling is sound, the same sound that you are hearing. Your ears just have structures that turn those pressure waves into the thing we know as sound.\n\n"
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2nx0kq | Kingdom of Sardinia's place in Italian Unification in the nineteenth century | _URL_0_
In this fun map it shows the Kingdom of Sardinia was the main push behind Italian unification. Why were they the ones to do this and not another part of Italy? Nationalistic reasons? Power? Economic influence? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2nx0kq/kingdom_of_sardinias_place_in_italian_unification/ | {
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"Well, there is no clean cut explanation.\n\nHistorically the Duchy of Savoia (mainly centered in Piedmont, capital Turin), was the more expansionist Italian state from the late seventeenth century onward.\n\nThe dukes played an active role in all the European wars of the period, shifting their alliance between France and Austria, expanding their territory eastward toward Milan and acquiring Sicily and the title o King (Sicily was later exchanged with Sardinia).\n\nSo it was already their long time goal to acquire the duchy of Milan.\n\nThere were also other factors: it was the more independent minded Italian state, and also the more open to external influences; it certainly had the more advanced and powerful military at the time (not counting the Austrian garrisons). Milan was maybe a more advanced city, but as it was under Austrian rule (along with Lombardy and Veneto), it could not be a fulcrum for independence (there was a revolt in 1848 where the city expelled the Austrian garrison, but it was short lived, and anyway it immediately asked for military support from Piedmont).\n\nRegarding the other states the duchy of Parma, Modena and Tuscany were closely aligned with Austria; the Pope was not interested in territorial expansion, and this also limited any ambitions from the Kingdom of Naples and Sicily (who could not well invade the territory of the Pope).\n\nAt the time a complete takeover of Italy by Piedmont was not a given. There were many other hypothesis, like a federation of independent states, with the expulsion of the Austrians, the duke of Piedmont as the Military commander and the Pope as the president of the federation.\n\nAfter the war of 1859 actually there was no impetus for further expansion from the duke of Savoia, Vittorio Emanuele II; he had gained the duchy of Milan from the Austrians and modern Emilia-Romagna and Tuscany by plebiscite, and he was pretty satisfied. There were proposals for a federation of three states, north Italy under the Savoia in the north, the Pope in the center and the Bourbon in the south.\n\nBut then Garibaldi mounted its expedition and conquered the Kingdom of Naples and Sicily with an army of volunteers. At this point Piedmont intervened, as it had no wish for the potential establishment of a republic in the south, and the kingdom of Italy was formed.\n\nSo there was more than a factor in play:\n\n- the dynastic impetus of the Savoia to expand, playing the French and the Austrians one against the other\n\n- a strong desire of a large part of the elites of the various Italian states to expel the Austrians and to form some sort of united entity in Italy, with the awareness that only the Savoia had in practice the inclination and the capability to push for this same objective\n\n- the relative fragility of the governments of the other states once the protection of the status quo by the Austrians was removed"
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1k8ye7 | Do we know of any chants that galley sailors would sing while they rowed? | Or was there a standard speed that galleys usually travelled at? I'm mostly interested in the galleys around the Hellenistic period, but I'll take information on sailors from any of the Mediterranean cultures. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1k8ye7/do_we_know_of_any_chants_that_galley_sailors/ | {
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"It's unlikely that they sung - that would not be conducive to rowing, which is physically tiring. It has been theorised that they may have hummed, which is less tiring, but there is no substantial proof of this. [A reconstructed trireme was tested using various means of synchronisation - humming was reportedly effective.](_URL_2_)\n\n[You may find this source useful, though I do not know how you might best access a full version of it](_URL_1_); 'The Athenian Trireme: The History and Reconstruction of an Ancient Greek Warship,\n By J. S. Morrison, J. F. Coates, N. B. Rankov'.\n\nEdit: See also [The Trireme](_URL_0_), by Prof Boris Rankov (Royal Holloway), also a rower."
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"http://www.hoplites.org/HAmember/The%20Trireme%20by%20Boris%20Rankov.pdf",
"http://books.google.co.uk/books?id=wVT71_6zLygC&pg=PA252&lpg=PA252&dq=ancient+greek+trireme+hum&source=bl&ots=dRkXO5vDJl&sig=M_9iIcAEi-ScqNfWmgzML5fZvJ4&hl=en&sa=X&ei=vJEJUtvuKqmq7QaYiYGIAg&redir_esc=y#v=onepage&q=ancient%20greek%20trireme%20hum&f=false",
"http://www.independent.co.uk/news/uk/oarsmen-learn-the-secrets-of-ancient-greek-war-machine--almost-unbeatable-in-battle-the-triremes-still-had-flaws-david-keys-reports-1491983.html"
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umi4r | Why do certain musical scales sound happy, scary , eerie, etc? | Some of my oldest memories is of being scared and saddened by songs in minor scales, and cheered up by songs in major scales. Is this something learned or in our DNA?
| askscience | http://www.reddit.com/r/askscience/comments/umi4r/why_do_certain_musical_scales_sound_happy_scary/ | {
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"Im not aware of a ton of work in this area, but one guy who is sorta studying this is Gilden at UT Austin. Though he mostly focuses on the nature of musical \"groove\". It's a bit of a new line for him, but he talks briefly about it on his site (_URL_0_). The guy is crazy smart though, so if you're interested keep up with him. Used to be an astrophysicist trained by a nobel laureate before switching to psychology. As for pop science, you might check out an Oliver Sacks book called Musicophilia if you haven't already. Also, there's this scientific american article from a while back, ( _URL_1_ ). I dunno how particular an answer you're looking for, but hopefully something there will interest you more than being called a dumb fuck.",
"Some of it has to do with [consonance and dissonance](_URL_0_).",
"i am not a scientist, but a reasonably educated musician.\n\nthe associations with scales is largely cultural. minor scales are not sad in all cultures. however, minor scales, because of how the notes compare to the harmonic series, tend to resolve downward to structural pitches rather than upward, which accounts for a lot of the difference.\n\nthere are also modes of the major scale. a mode is the same pitch relationship starting on a different pitch. natural minor is the 6th mode of the major scale, meaning you start on the 6th degree and play all the notes in the octave. lydian (major, aka ionian with a raised 4) is the brightest mode, and you can hear how bright and \"up\" it is in for example the simpsons theme song or in the 3rd movement of [beethoven's op 132, (starting at 19:24)](_URL_0_)\n\n(EDIT: and for the record, that string quartet is one of the finest chamber works ever, in my opinion. the third movement is the high point of the work, but it's worth listening to the whole thing. there was such a stir about it, that schubert requested to hear it his deathbed, and his response was \"after this, what is left for us to compose?\" AND beethoven was stone deaf for years before he wrote it. impressive guy.)\n\ni'm afraid the ability to scientifically determine what's going on once and for all is rather limited at this time, because in addition to physics/acoustics, we have to deal with psychoacoustics (how our brains process sounds, deleting and adding content from different combinations of pitches and harmonics), cultural training, and personal associations.\n\nEDIT: thanks to z3ugma for the youtube link that takes you to the right spot in the video.",
"I'm not sure how well versed in music you are, but the primary difference between a major and minor scale is the 3rd note of that scale. Most of the others stay the same (the rules changing depending on the type of minor scale, but that is more of a music theory question than a psychology question). \n\nSo let us focus a second on the third note of the scale. Basic chords are made up of the root note, the third (be it major or minor), and the 5th. In a well tuned instrument, the 5th has a pitch ratio of 3:2, meaning that for every 3 vibrations of the upper note, the lower note will vibrate two. This creates a generally pleasing effect as the waves that make up these notes restart at the same place every 6 cycles. \n\nNow we look at the major 3rd, which has a pitch ratio of 5:4, which is also pleasing as we hear a sync with the root every 20 vibrations. The minor 3rd, which has a pitch ratio of 6:5, is somewhat less pleasing. \n\nSo you may be asking what this has to do with speech. In normal conversation, the notes our voice makes are rarely larger than an octave. In fact, most speech is within a half octave range (I don't have a source for this, sorry). That means that in order to convey meta-information, we must listen to the subtleties of voice inflection. One who is sad is less likely to add emphasis to certain non-monosyllabic words, thus dropping the pitch, raising the pitch ratio, etc. etc.\n\nThink of Eeyore from Winnie the Pooh, and the way he says his name. I'm sure if you say it his way, and then say it as if you were happy to be saying the name, you'd be dropping a major 3rd rather than a minor 3rd. \n\nWe have become quite adept at picking out these subtleties. Here's a paper on how good we actually are: _URL_0_\n\nSorry if this is a bunch of disjoint ideas. Hopefully it helps!",
"I highly recommend Dr. Daniel J. Levithin's *This is your Brain on Music.* ",
"A *lot* of this is cultural, but some of it is related to physics of sound. \n\nBrushing aside a ton of stuff and zeroing in on western equal-tempered stuff, and then over-simplifying to boot...\n\nA real-world \"note\" produced by an instrument or voice has an infinite sequence of harmonic overtones (you can think of them as \"higher notes\" simultaneously produced by fractional vibrations of the air or wood or string or whatever). Smaller \"fractions\" are the most prominent ones (1/2, 1/3, 1/4, 1/5, etc...)\n\nCertain intervals in the 12-tone scale correlate \"perfectly\" (or at least very closely) with prominent harmonics of the root note (perfect fifths and fourths, octaves). These are \"neutral\" and sound neither major nor minor, they just sound sort of consonant and \"reinforcing\" of the sonic texture of the root note.\n\nOther intervals do not correlate to any of the prominent harmonics and sound obviously \"dissonant\" (flatted 2nd, tritone, etc). These again do not sound obviously major nor minor without context, just dissonant and \"unnatural\" and jarring. \n\nNow, there are other intervals (especially thirds) that are close to but not quite right on top of prominent harmonics. The major third is slightly sharp of the \"perfectly\" consonant interval that an untrained ear \"expects\", and the minor third is slightly more flat of the same \"blue note\" or \"perfect third\" that doesn't quite exist on the scale, but that does in nature (sort of). \n\nAs a result, a major chord or passage with a major third suggests a rising pitch, which is a sonic effect we associate with approaching things, excited speech, eagerness, and rising volume. \n\nOTOH, a minor chord, with it's \"flat\" interval, suggests receding sound, decaying sound, and quiet or somber speech. \n\nPart of these associations are due to things like doppler effects and the way that frequency perception changes with volume and distance, and part is related to how speech patterns reflect emotion (which might in turn be related to the former). \n\nFar more importantly, music creates its own impressions and expectations. Progressions and intervals might suggest certain physical phenomena or speech patterns, but they also suggest other songs and melodies you have heard or known, and the associations you have with them. \n\nFor an interesting example of how these kinds of associations and sonic effects interact with the emotional content of a piece of music, try playing [\"Happy Birthday to You\" in minor](_URL_0_), it sounds like a dirge, or something sinister and fatal. ",
"i actually did a paper on this for one of my college courses. It was very interesting to see that while some is obviously based off of culture and where you are in the world how you are conditioned to react to certain types of sounds (example: jaws music putting you on edge) a lot of seems to be for lack of better words \"pre-programmed\". There were extensive studies done with with babies reacting to certain sounds like perfect fifths positively so i think there's something in that",
"Part of it may have to do with the fact that we are constantly processing scales. Not musical scales, but all sorts of scales. What is a scale? It associates, etymologically, with climbing, and has a general meaning of a kind of traversing and measurement. We are constantly scaling: we view the face of another and \"scale up and down\" the person, their body, their face. We scale stairs: starting, we make our way up or down. We constantly measure, and that measure has a \"scale\" to it: a sense of things across, up and down, etc. We even \"measure\" situations in various ways. We scale our speech, step it up or down, etc. The issue is to draw the connection between the musical scale as such, which will be mentioned in light of your question and is not hard to see, and the scaling we do all the time. \n\nSo take the sense of \"scale\" in a kind of expanded sense that includes a few basic features: a measurement and span, roughly. So just how much of this \"scaling\" do we do? The question is more like: when *aren't* we in an \"scale\" of some kind? Look at any situation you're in and ask yourself where there is a \"traversing measurment\" involved. Whether it's walking to the coke machine or ambling slowly to someone you need to say something uncomfortable to, we're always scoping out and being in some degree of placement, commencement, passage through, etc., various \"things\", all sorts of things. Any \"thing\" in the physical sense has a \"scale\" in it: looking across the thing from left to right, or up and down, etc. Little moments and broad passages. A week is a kind of scale: seven days, one to the next, with a sense of middle, then TGIF, then the weekend, you name it, there's a \"scale\", a line, a measurement in it, a traversing or possible traversing. \n\nSo we have a constant cognitive mechanism of engagement with scales. So when we hear scales, we have a big serious of operations going on that get sparked and engaged. It's on this basis that musical scales have meaning for us, I think. Also, it seems important to include in this internal scales and balances: so we're constantly in scales within ourselves, in our emotions/feelings, though how \"scaling\" as such occurs in this seems a little harder in some was to see, in other ways not. Some comments have mentioned the \"up and down\" of the voice, the natural range of speaking, and how we traverse that range and have predilections for parts of that range, how we are primed to meaning on the basis of placement in that range. \n\nSo you can go on about how the musical scale has signal points, such as the median or 3, which can be high or low, with implications. And that's all true enough, but it seems quite important to realize that we are involved in scales all the time, as I suggested and not just when hearing music. Is there a do-re-mi of the face? Kind of, yes. And of every sentence in this comment, in a way. \n\nSo then the question is: What happens when a musical scale comes into contact with the \"scaling human\". It sets off all kinds of associations. Or can."
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rjisw | Is depression more frequent amongst people in developed countries? | I live in a highly privileged country (Norway), and yet my impression is that a lot of people here are depressed. In a peaceful society you don't have to tackle a lot of serious day to day-problems of the kind you might see in underdeveloped countries, or even in America. Things like fighting for your life, your rights, your freedom and your economy are fringe problems in our country. Still I get the impression that there is too much depression.
**edit: grammar.**
**edit2: semantics and grammar + thank you so much for many interesting and well-supported answers!**
**edit3: I'm relatively new to reddit, but the amount of effort many of you people put into these answers, the subsequent inquiries and your heroic pursuit of truth in the face of some of the more speculative non-scientific unsupported babble you often find on this subreddit, it just blows me away sometimes. A second thanks to the people who go out of their way to find well-backed sources on a subject often overlooked and misunderstood.** | askscience | http://www.reddit.com/r/askscience/comments/rjisw/is_depression_more_frequent_amongst_people_in/ | {
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"I do not believe we have strong data about depression amongst underdeveloped nations, so this comparison may not be possible.",
"_URL_0_ \n(Bokmal) _URL_1_\n\nI don't know about depression in general, but Scandinavia has a very high rate of seasonal affective disorder thanks to its latitude.",
"A [2011 study](_URL_1_) reported:\n > On average, the estimated lifetime prevalence [of depression] was **higher in high-income (14.6%) than low- to middle-income (11.1%) countries** (t = 5.7, P < 0.001). Indeed, the four lowest lifetime prevalence estimates ( < 10%) were in low- to middle-income countries (India, Mexico, China, South Africa). Conversely, with the exception of Brazil, the highest rates ( > 18%) were in four high-income countries (France, the Netherlands, New Zealand, the USA).\n\n...and generally that:\n > Consistent with previous cross-national reports, the WMH MDE [World Mental Health major depressive episodes] prevalence estimates varied considerably between countries, with the highest prevalence estimates found in some of the wealthiest countries in the world. \n\nThe researchers provided several possible explanations for these results (including the suggestion that [\"depression is to some extent an illness of affluence\"](_URL_0_)), but also **acknowledged several limitations and that their findings might be due to recall error**. They concluded **more work needed to be done**. \n\nEdit: more bold for clarity.\n\nEdit 2: **Social context is indeed a known issue**, in addition to many other factors. Please refer to Epilepep's remarks, which have unfortunately become buried. \n\nAlso, **please (at least) read the methods** of the paper before commenting about potential errors in data collection. This study may not be completely culturally sensitive, but efforts were made to conduct the face-to-face interviews as objectively as possible. For instance, the \"interview translation, back-translation and harmonization protocol required culturally competent bilingual clinicians in the participating countries to review, modify and approve the key phrases used to describe symptoms of all disorders assessed in the survey\". \n\nThe researchers explicitly noted that \"no attempt was made to go beyond the DSM-IV criteria\", but stated that \"as noted in the introduction, previous research has shown that the latent structure of the symptoms of major depression is consistent across countries, providing a principled basis for focusing on this criterion set in our analysis\".\n\n**Again, the authors of this paper made a very cautious conclusion**: \n > MDE is a significant public-health concern across all regions of the world and is strongly linked to social conditions. Future research is needed to investigate the combination of demographic risk factors that are most strongly associated with MDE in the specific countries included in the WMH.",
"Depression is a funny thing. In different cultures it is defined differently. In the 1960s the World Health Organisation conducted a study to determine exactly this. I can't find a page linking to an example of the study, but they found something along the lines of nobody in Africa is actually depressed. This was because the WHO was organised and developed in westernised countries and the cultures in Africa did not lean to the definition of depression we had then. \n\nThis also translates to collectivist cultures in countries such as Japan and China which only recently developed an increase in the number of cases of minor depression. This is largely believed to be because of the exposure of western individualist cultures as opposed to their usual collectivist nature and the influx of pharmaceutical companies marketing anti-depressants. An article on the Japanese influence [here](_URL_0_).\n\nIt's difficult to find the World health organisation study on this. Can anyone help me? I am unsure about the facts I stated because I read this a while ago.",
"A passing observation would be the amount of psychiatrists/psychologists per 100 square miles would be related with diagnoses of mental illness in the area -- that would be a lengthy study though.",
"[Statistics I have seen](_URL_0_) show Scandinavian countries as some of the happiest so I am confused how one can be depressed overall, yet one of the happiest nations? Maybe everyone is depressed?",
"There are some significant differences between organic mental illness and situational emotional response. But they are hard to separate out without real effort, because they share many symptoms in common.\n\nThere is no reason to believe that the incidence of various organic mental illnesses in general populations (not counting small isolated gene pools) has varied much around the world, nor throughout history.",
"i heard depression is particularly common in scandinavian countries and those towards north pole(iceland, northern russia etc). apparently its probably linked with the long nights and short days and perpetual coldness over the winter months.\n\ni guess the problem would be the same approaching the south pole if any significant population actually lived down that way...",
"I see very little here about how depression can be genetic.",
"Higher income societies are more materialistically based. Which has a significant bias towards a few individuals who can afford to have sought after things. The majority that cannot afford those things, and have the intelligence to realize that they can perhaps never get those things, become depressed because social influences dictate that they are lesser people for not having those \"things\". Societies that have a less materialistically based culture will have less depression.\n\nIt is a phenomena that would take some time to describe, but that is the general idea behind it. I would also mention that collectivistic cultures will also have significantly lower depression rates than individualistic cultures. ",
"[I'll just leave this here](_URL_0_)",
"TL;DR Suicide rates skyrocketed when people lost specific roles in life. Going from a farming oriented ife, where everyone was born into specific lifelong roles, to a privilaged city life with a multitude of free choices lead to stark increase in suicides. Which could mean that people in developed countries indeed are prone to more depression.\n\n\nOne of the fathers of sociology studied suicide rates extensively.\n\n\n_URL_0_\n\n\nI don't believe he directly addressed whether or not development had an affect, but I believe his findings are very relevant to this discussion.\n\nPlease correct me if I over simplified it.",
"No doubt depression is diagnosed more in developed countries because more people have access to diagnosticians, so I think this will be a hard question to answer.",
"Depression (or at least the diagnostic criteria for it in the ICD-10 and the DSM-IV) is at least partly a Western phenomenon. Culture does have a significant part to play in how people describe what's going on with them psychologically, and some cultures, particularly non-Western ones, may describe what we would think of as \"depression\" as something entirely different. (This is part of why the psych program I graduated from put so much emphasis on multicultural approaches to treatment.)",
"I think the word you're looking for is *ennui*",
"I'd recommend looking at the theory of anomie. Durkheim mentions some great ideas in his theory of anomic suicide, which occurs mostly to people in cities and other developed areas. I'm on a phone so all I can do is give you this link: \n\n_URL_0_",
"developement leads to- education leads to- intelligence leads to- knowledge leads to- wisdom leads to- realization leads to- depression. It's an old concept.",
"I highly recommend checking out the book \"The Spirit Level\"\nIt uses statistical data to show a significant positive trend between depression and inequality, as opposed to total income level",
"Someone did a TED talk that convinced me of why this is. [Here's the link.](_URL_0_)"
]
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"http://en.wikipedia.org/wiki/Seasonal_affective_disorder#Incidence",
"http://no.wikipedia.org/wiki/Sesongavhengig_depresjon"
],
[
"http://www.ncbi.nlm.nih.gov/pubmed/19855219",
"http://www.biomedcentral.com/1741-7015/9/90/abstract"
],
[
"http://www.nytimes.com/2004/08/22/magazine/did-antidepressants-depress-japan.html"
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[],
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"http://www.forbes.com/2010/07/14/world-happiest-countries-lifestyle-realestate-gallup-table.html"
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[],
[],
[],
[],
[
"http://en.wikipedia.org/wiki/File:Self-inflicted_injuries_world_map_-_Death_-_WHO2004.svg"
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"http://en.wikipedia.org/wiki/Émile_Durkheim"
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[],
[],
[],
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"http://en.m.wikipedia.org/wiki/Anomie"
],
[],
[],
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"http://www.ted.com/talks/barry_schwartz_on_the_paradox_of_choice.html"
]
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|
9zdrzx | what is more dangerous for the human body. high ac or dc and why? | We had a Discussion in physics if high ac or dc is more dangerous since high frequent ac isnt as dangerous as low frequent so we were not sure | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9zdrzx/eli5_what_is_more_dangerous_for_the_human_body/ | {
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"The biggest advantage to AC is that it fluctuates the level, which gives you more of a chance of disconnecting from it. DC will lock your muscles and keep you from letting go.",
"Low-frequency AC is more likely to disrupt your heart rhythm than DC, but DC can still do that. High-frequency AC is extremely unlikely to stimulate nerves in a way that causes damage, which is why there are surgical tools that apply HF currents to body parts.",
"Well high AC will make you less likely be hit and avoid damage at all. But high DC is also hard to beat, especially if your saving throw is low and the failure can be critical.\n\n & #x200B;\n\n\\#Dndthings"
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16b161 | How do changes in Earth's global temperature caused by Milankovitch cyclicity compare to other climate change sources (anthropogenic and other)? | I am currently studying geology at a very conservative university (Texas A & M), If someone mentions climate change in any of my classes there is immediate laughter. Not because the idea is ridiculous, but because of the fuss people(from my experience usually non scientists) make about it. As geologists it is the most basic tenet of our discipline that Earth is constantly changing. That being said I am not a climate scientists and have only a rudimentary understanding of atmospheric science. I am seeking the help of an expert. Thanks! | askscience | http://www.reddit.com/r/askscience/comments/16b161/how_do_changes_in_earths_global_temperature/ | {
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"[This page at skeptialscience](_URL_0_) discusses Milankovitch Cycles and cites the variation of solar forcing due to orbital eccentricity as ~0.45 W/m^2. Current estimates of anthropogenic alterations to the radiative balance ([see IPCC](_URL_1_)) are about 1.6 W/m^2. So variations in forcing due to Milankovitch Cycles were less than 1/3 as strong as the current anthropogenic perturbation."
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3rl322 | Washing clothing that was not color fast. | About washing clothes. Before modern dyes most colors would not have been color fast. Yet clothing had to be cleaned at least occasionally. I realize that layering garments would have permitted washing like colors together and that sashes, lace, and other ornamentation could be removed and resewn after cleaning. Paintings of medieval peasants show colorful but monochromatic clothing. But what of, for example, the beautiful designs of Japanese kimonos or the embroidered (?) dalmatics of Theodora's attendants in the famous Ravenna mosaic? In the absence of dry cleaning how were these items washed? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3rl322/washing_clothing_that_was_not_color_fast/ | {
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"To cover the basics first, dyes before modern dyes were color fast and dry cleaning did exist. One of the most popular dyes still today is indigo. Interestingly it doesn't dissolve in water nor adhere to fabric, so how does this work? You need an alkaline solution such as lye, ammonia, or urine in order to dissolve the indigo. Once set into the fabric, water won't wash it out. Other dyes that are water soluble will still be color fast because of the process of using a mordant. The New Pocket Cyclopaedia of 1813 lists common mordants as \"sulphate of alumine, oxide of tin, oxide of iron in combination with acids, oxide of arsenic, tan, & c.\" It goes on to say that the most permanent dyes are cochineal and gum-lac (scarlets), indigo and woad (blue), dyers weed (yellow), and madder (coarse reds, purples, blacks). Mordant can be added before, during, or after the dying process depending on the chemistry needed. It does change the final dye color. Iron oxide mordants are notorious for their deterioration of textiles, and are the reason so many black garments survive in terrible shape if at all. Basically mordants help the dye to bond to the textile and keep it much more permanent. Silks and wools do incredibly well with this, linen less so and it's harder to get a dark color set into it for that reason.\n\nWhen it comes to cleaning you are very correct about not having to wash exterior pieces often (if at all). Undergarments were white for this reason, being able to be bleached and boiled to make them clean. Outer garments can sometimes be washed and submerged in water, but more often are spot cleaned based on the exterior dirt/stain. Dry cleaning by definition is simply cleaning with something other than water. For example, if you got a grease stain on silk (due to the carriage or dinner), it gets sprinkled with fullers earth, covered in paper, and a light amount of heat applied. This will draw out the stain (in modern day use baby powder to much the same effect). To remove any remaining rings you can wash the area with soap and water, washing it out with gin, and then washing it out with water. If the entire garment must be wetted to keep from getting water rings you'll wrap it up in a towel immediately to dry. Cook books often have recipes in back for laundering. And if you don't want to deal with it professional laundering can be had as well."
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yjenl | Suppose we had working fusion reactors with the output and specifications we're working towards? What implications would it realistically have for other energy sources and humanity in general in terms of the other problems we have? | By output and specifications we're looking for, I mean based on what size we predict them to be, amount of output per generator etc.
What it cast all form of existing electricity generation into obsolescence?
How big would they need to be, including surrounding safety equipment? Would they be mobile?
Would they require as many safety precautions as existing fission plants or would the reaction simply be extinguished in the event of an equipment failure?
Would it open many possibilities for projects whose energy demands would have made them perviously unfeasible due to their energy demands? E.g. CO2 sequestration, huge aircraft (similar to [The Valiant in Doctor Who](_URL_0_)) etc..
Thanks, | askscience | http://www.reddit.com/r/askscience/comments/yjenl/suppose_we_had_working_fusion_reactors_with_the/ | {
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"Engineering student here.\n\nRegarding size, mobility - large, more or less immobile. ITER is large - it's a technology demonstrator for a power station. The reactor itself, plus all the necessary hardware to actually produce power (steam generation, turbines, generators, heat dumps) would take up even more space. I figure it could fit into a large ship, but I haven't even done napkin math. \nAssuming ITER works, we'd still be a very long way from fitting one into, say, a car or truck.\n\nWould it obsolete existing generating sources? Probably not. Coal is cheap - at the end of the day, coal, oil, nuclear (fission and fusion), solar thermal, and (part of) combined cycle gas are just different ways of boiling water to turn a turbine - and coal is dirt cheap.\n\nSafety - I'd need someone else more qualified, but as I understand it, there's no risk like those with fission plants. There simply isn't enough mass available at any given moment to go runaway.\nWaste-wise there's no heavy metal, radioactive fission products. They would produce radioactive tritium gas, and anything nearby would become radioactive due to neutron bombardment, and would need to be disposed of carefully.",
"Hi! I'm a fusion researcher (tokamaks, specifically). These are some interesting questions. Let's see:\n\n > I mean based on what size we predict them to be, amount of output per generator etc.\n\nSome of the other replies have already talked about ITER for a sense of scale. An actual power-plant tokamak (a concept called DEMO) would be somewhat larger than ITER based on an ITER-like design - ITER is more the proof of concept of scaling our existing fusion experiments up to power-plant sizes, rather than a power-plant prototype itself.\n\nThe trick is, tokamaks generally get substantially more efficient the bigger you make them, the tradeoff being that the capital cost to build the power plant becomes unfeasibly high. You could actually build a fusion power plant right now, using only reactor tech and plasma physics we've understood since the 1980's. The problem is, to compensate for the crappy plasma behavior you'd have to make the tokamak huge (major radius of around 20 meters, compared to 6 meters on ITER). Since the major cost-of-electricity from a tokamak would just be the cost of building it amortized over its lifetime (since operating costs would be very low), this puts the cost per kWh out of an economically competitive range. The idea, then, is to build the tokamak as small as possible while still having efficient output. Based on a number of advances in reactor tech (particularly superconducting-magnet design) and plasma physics, it could very well be possible to build a power plant *smaller* by a significant margin than ITER.\n\nAll that said, you're generally looking at a power plant facility (tokamak, fuel handling, and all the ancillary structures) with a footprint of comparable size to an existing fission power plant, putting out in the neighborhood of a GW electric. There's actually some concern that building a tokamak large enough to be efficient would actually produce *too much* power for a single point-of-generation on our existing grid; in such a case, some of the power would be diverted to other energy-intensive uses, like hydrogen fuel cell charging or pumped-water storage.\n\n > What it cast all form of existing electricity generation into obsolescence?\n\nNot entirely. So every form of power generation has strengths and weaknesses, even fusion. Trying to pick one and saying \"this is how we will power America\" very quickly becomes a round-pegs-in-square-holes type of problem. What fusion can do is this: large-scale (GW+), always-on baseload power without environmental pollution or risk of radiation, and with *extremely* plentiful fuel. This means it can entirely replace coal-fired power plants, for example, and many existing fission plants (though I'd forsee small modular fission reactors as another viable option for certain situations). There will also pretty much always be regions where wind, solar, or hydroelectric are more economical - remember, I said the limiting factor on fusion power is the capital investment needed to build the plant. Generation from wind or solar is geographically dependent, though - so a fusion plant can get (comparatively) compact power generation easily for high-draw areas, like near population centers.\n\n > How big would they need to be, including surrounding safety equipment? Would they be mobile?\n\nI think I've addressed this rolled into my responses above. To reiterate - a footprint for the entire power plant comparable to existing fission plants. However, thanks to the inherent safety of fusion plants (more on this later) the area around the compound would be far more usable, rather than the \"no-man's land\" typically found in the immediate vicinity of fission plants.\n\nDue to their size, it's unlikely that fusion plants would be mobile in the near future. However, the high power output at a single point of generation does lend itself to mobile energy forms like hydrogen cells.\n\n > Would they require as many safety precautions as existing fission plants or would the reaction simply be extinguished in the event of an equipment failure?\n\nThis is one of the biggest wins for a fusion plant - they are *extremely* safe. Even in the event of a catastrophic loss of confinement, the nature of the reaction is simply to burn itself out, rather than run away. Part of this is due to the nature of the fuel - fusion fuel would be gas continuously pumped into the reactor, rather than solid fuel rods stored in the reactor vessel. A fission plant contains a year's worth of fuel at once - this is a huge source of free energy in the case of a meltdown. In a fusion plant, the fueling cuts off as soon as you lose confinement. It's rather like the difference between turning off the ignition in your car, versus lighting the gas tank on fire. \n\nEven if you continued fueling, losing the confining magnetic fields and heating would cause the plasma to rapidly expand and cool, contacting the reactor walls. Though the plasma is very hot (~150 million degrees C), there is very little of it - ITER, for example, would contain less than a gram of fuel at a time. Any contact with the wall would rapidly cool the plasma, re-neutralizing it and burning the plasma out. This would cause serious (read: expensive) damage to the wall, but presents basically no safety risk. ITER's own safety plans (per their licensing with France's nuclear regulatory commission) mandate that even in pretty much the worst case, you don't need to evacuate outside the facility perimeter.\n\nAs for waste: fusion reactions produce *very* little radioactive waste, and what there is is relatively easy to handle. For one thing, half of the fuel (deuterium) is nonradioactive, and the other half (tritium) is short-lived, so there would be very little stored on-site (it would actually be manufactured in the reactor shielding itself!). The high-energy neutrons produced by fusion reactions would activate structural materials in the reactor, creating some radioactive waste. However, we can engineer these materials to be somewhat resistant to damage, and they largely retain their solid, chemically-inert form (compared to fission waste, which is a toxic, radioactive slurry in addition to being radioactive), so it's relatively easy to handle. All in all, the waste handling from a fusion plant would be more like that for a hospital radiology department, rather than like a fission plant.\n\n > Would it open many possibilities for projects whose energy demands would have made them perviously unfeasible due to their energy demands? E.g. CO2 sequestration, huge aircraft (similar to [1] The Valiant in Doctor Who) etc..\n\nYes, at least in stationary activities (desalination, water cracking for hydrogen and oxygen, hydrogen fuel cell charging). A large plane would be unlikely, given the weight of a full-power tokamak. \n\nAs for WarPhalange's concern about fuel - that would be less of an issue. Fusion fuel (DT, specifically) has around 10 times greater energy density per mass than fission fuel.\n\n*edit:* check out this [AMA](_URL_0_) several researchers from my lab did a few months back - I like to point to it, since we had a pretty broad discussion. May give you more ideas for questions!"
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2ciivm | How have norms against attacking civilian populations developed and been applied by Western countries post WW2? | In the Second World War, the UK began a bombing campaign against German cities, with the aim of damaging the 'morale of the enemy civil population'. The US later joined in the bombing campaign (though maybe not with the same explicit aims?), and began its own bombing campaign in Japan. Firebombing of Tokyo killed up to 100,000 people, and the two atomic bombs killed over 150,000.
It seems - and correct me if I'm wrong - that attacking civilian populations like this was deemed acceptable by the US and UK, even if it remained controversial.
Today we live in a world where this sort of indiscriminate attack on civilian targets is usually judged unacceptable both morally and legally. The 1949 Geneva convention put in place some somewhat vaguely defined(?) protections for civilians. The 1977 addition makes these protections more specific, prohibiting "indiscriminate" attacks, and giving some detail on what this means.
So I have two related questions.
The broader one is: how have we got from there to here? When did Western militaries accept and start teaching that this was unacceptable? What resistance has there been to the changes? How was the discord between this norm and the doctrines of nuclear war managed?
The more specific question is: what instances after 1945 are there of Western militaries attacking civilian targets with the explicit or implicit aim of coercing the civilian population? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2ciivm/how_have_norms_against_attacking_civilian/ | {
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" > The more specific question is: what instances after 1945 are there of Western militaries attacking civilian targets with the explicit or implicit aim of coercing the civilian population?\n\nWell, for one, the Korean War which began in 1950 saw the US use B-29 bombers to bomb Pyongyang and other cities in North Korea. However, as I'll explain later, the deliberate targeting civilians already begun to fell away as a strategy.\n\n > The broader one is: how have we got from there to here? When did Western militaries accept and start teaching that this was unacceptable? What resistance has there been to the changes? \n\nStudies after WW2 were conducted about the effectiveness of strategic bombing. It found that the deliberate targeting on civilian centers wasn't all that effective in terms of breaking the civilian morale. Not only did strategic bombing of German cities day and night not end the war any sooner (the Soviets taking Berlin and the Allies closing in from the west prompted their surrender), but the Allies suffered their own forms of bombing (England during the Blitz) and instead found their citizens more resolute in defending their own homes.\n\nWhere strategic bombing did become more useful was when it was targeted at infrastructure and other assets that their military would use. Bridges, rail centers, transportation hubs, etc. You see this in Korea where B-29s started dropping radio bombs to target bridges/railways, and in Vietnam even our major bombing campaigns with strategic bombers like the B-52 (e.g. Operation Linebacker II) were targeted at ports, railways, supply depots, etc.\n\nAnd finally, beyond the fact that military studies finding deliberate targeting of civilian centers being less effective, there was the fact that warfare had changed.\n\nToday it takes a single B-52 with a crew of 5 to drop the same amount of bombs that 16 B-17s with 160 total crew members took from London to Berlin. And oh yeah, that B-52 took off from Louisiana.\n\nBecause of this, we employ far fewer bombers - which also makes each bomber significantly more valuable. Losing a B-52 much less a B-2 today would be extremely costly - instead, we employ our bombers completely differently. We found, during Vietnam, that bombers like the B-52 could be very vulnerable to surface to air missile systems.\n\nHence, in the post-Vietnam era, the USAF focused on fast bombers that either flew extremely high (like the XB-70) or low (like the B-1) and then on stealth aircraft (the F-117 and then of course the B-2). The B-52 has become more tailored to carrying long range cruise missiles as a stand-off missile platform (though it can carpet bomb as it used to as well).\n\nSo to answer your question: the studies done after WW2 and the lessons learned in Korea and Vietnam have changed military doctrine regarding aerial bombardment. Not only that, but changes in air defense and in bombing technology have more or less ended the days where bombers fly in massive formations to indiscriminately carpet bomb large areas.\n\n > How was the discord between this norm and the doctrines of nuclear war managed?\n\nNuclear war has been treated as a separate entity from strategic bombing really ever since the Soviet Union developed their own nuclear weapons and the capability to deliver them.\n\nThe idea of mutually assured destruction has more or less relegated nuclear weapons into two categories: tactical and strategic, with strategic being more aligned with the idea of wiping out an entire civilization.\n\nBoth sides drew up numerous use cases for nuclear weapons. Some believed that tactical exchanges against enemy armored formations would be acceptable - indeed, it was suggested that if the enemy used nuclear weapons strictly on military targets only, we'd respond in kind.\n\nThe whole idea that \"if one nuke goes off, we wipe them completely out\" is a misconception a lot of people have about nuclear weapons. All that stuff is way above public discourse for obvious reasons, but using nuclear weapons to wipe out an entire country's populace is not a frequent reason for the use of nuclear weapons."
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244y1q | how do enzymes actually lower activation energy? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/244y1q/eli5_how_do_enzymes_actually_lower_activation/ | {
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"The reactants don't immediately form products, they'll form a transition state first, and the energy needed to form it corresponds to the activation energy.\n\nA catalyst (including enzymes) will make a transition state available which is lower in energy than the one which is used without the catalyst. Therefore the activation energy corresponds to the new lower-energy transition state.",
"Basically they grab the substrate and hold it in the right configuration for the reaction to go.",
"Enzymes alter the chemical structure of the substrate slightly to make it more likely to undergo change. \n\nSo, you have your enzyme and substrate which collide at the right angle and with sufficient energy to form an enzyme-substrate complex. The bonds between these two cause a small change in the structure of the substrate for the change to happen, then then the new molecule (substrate) is released by another chemical change. \n\nIn my Biochemistry I class we focused on the mechanism for chymotrypsin goes through. See the mechanism [here](_URL_0_).\n\nHope this helps! \n\nEdit: spelling.",
"An answer I know! \n\nThere are several reasons that enzymes lower activation energy, the primary reasons being that:\n\n* an enzyme aligns two substrates together in such a way that make the substrates react better/faster. Think of two lego blocks being two substrates and our hands being the enzyme. Our hands align the legos in the appropriate way to stack together, or “react”. Otherwise, legos by themselves would fall on each other any such way, which won’t always make them stackable (imagine the top ends touching, for example). Less energy is needed for a reaction when the legos are arranged to bond more favorably, versus just being randomly mixed together any such way. **Enzymes align the substrates in such a way that make them easier to react.**\n\n* when an enzyme is bonded to a substrate to form a substrate-enzyme complex, the concentration of the substrate by itself is temporarily “decreased” around the enzyme, because the substrate alone becomes part of a substrate-enzyme complex. So this substrate-enzyme complex actually causes substrate concentration to readjust, bringing more substrate closer to the enzyme, to equalize concentration. In terms of equilibrium, substrate and substrate-enzyme complex concentrations are two different entities, but realistically, if forming a substrate-enzyme complex causes additional substrate to move closer to the enzyme, a reaction will more easily take place due to the greater availability of the substrate. **The concentration of substrate molecules naturally increase around an enzyme, due to the formation of substrate-enzyme complexes. With substrate molecules more readily available, reactions are more favorable.**\n\nWith both of these reasons combined, it is apparent why less energy would be needed to make a reaction occur with an enzyme. An enzyme arranges substrate in energetically favorable ways while also attracting additional substrate towards the enzyme. \n"
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57ss1w | why do some people believe ai (artificial intelligence) will take over the world | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/57ss1w/eli5_why_do_some_people_believe_ai_artificial/ | {
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"One of the larger concerns with AI is that if not programmed correctly, it will pose various risks to humans by simply being too good at its job. This is illustrated pretty well with the \"paperclip \nmaximizer\" thought experiment: \n\n_URL_0_\n\nIn addition, popular media has done a pretty good job of hyping up malicious AI as a possible doomsday scenario.",
"In theory, it might be possible for an AI to improve itself, becoming smarter faster than humans can keep up with it. It could become capable of doing anything with any computer system in the world (that isn't physically isolated), such as taking control of power grids, banks, dams, satellites, military hardware, etc These things are all vulnerable to human hackers but are defended by human means; an AI could overcome any possible defense.\n\nAn AI may be smarter than humans but lack morals, or have it's own alien morality system, for example it might see humans as the greatest threat to itself/the planet/the universe and so it may decide it should eliminate humans.\n\nAn AI controlling a toaster oven is not dangerous, but an AI that could both improve itself beyond it's design and take control of other systems would be incredibly dangerous.\n\nIt's just as likely that such an AI would seek to help humanity instead but that's less interesting as a literary conflict."
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2sfem0 | how is normalizing relations with cuba going to affect the us economy? | Bonus question: Why does the process take so long to do so?
I completely understand the reasons for lifting the embargo, but everyone I speak with says it's going to completely improve our economy. The most research I've found is by the US Chamber of Commerce, who said we're losing $1.2 billion in potential exports each year. Isn't that pennies to our economy?
Anyways, I've just been finding bias in the whole topic. I just need someone to explain as best they can how lifting it would affect our economy--both the positives and negatives. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2sfem0/eli5_how_is_normalizing_relations_with_cuba_going/ | {
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"It will have some positive effect, but I think you're right that it's not going to be hugely impacting one way or the other.\n\nLifting the embargo will take quite some time because our laws will have to change. There's no clear agreement that lifting the embargo is a good thing, and our lawmakers seem to be having a hard time doing anything at all lately.",
"From what I understand, this is a potentially great opportunity for many north american companies to start investing in a new market. If the embargo were to be lifted, and a while after Cuba restructures its local infrastructure and economy, we'll start to see companies such as GM or Ford shipping their merchandise over to Cuba. To keep this short, both the American and Cuban economies will be exposed to each others products which in turn will drive up the profits in a win win scenario for the U.S and Cuba.\n\nAs for negatives, the only that comes into mind in terms of economy, is that this lifting of the embargo could potentially affect Puerto Rico's economy. This is due to the fact that the U.S might shift market investments towards Cuba instead of P.R 's flailing economy. Then again Puerto Rico could benefit from the embargo if the countries leaders and businessmen decide to ship our local products and companies over to Cuba."
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ieekm | Is there a correlation between race and intelligence? | This is going to be touchy but I had a debate on whether one race's is superior to another in terms of intelligence (This might be touchy).
To quote from [another askscience post](_URL_0_):
> The cultural bias in IQ is one that most wouldn't touch with a 20-foot pole. Needless to say, many studies find differences in ethnicities irrespective of study wording or test-taking anxiety (see Herrnstein and Murray, 1994--"The Bell Curve", that sparked some HUGE debate/anger). Some say that you can order races on their intelligence with asians on top, indians and caucasians a little below, latinos/hispanics about 1/4 std. deviaiton below whites, and blacks about 2/3-1 standard deviation below whites. It's really shocking to see these differences emerge, but they're there, and few people are sure what to do about it. In hiring contexts especially, it's a big deal.
He argued that in general black people simply aren't as intelligent as other races. This is shown in modern day socities as well as their history which does not have the successes shown in other cultures (Aztecs, Chinese, European).
I argued that this was an unfortunate accident in history that overtime they were taken advantage of and as a result today they lack the opportunity and motivation to succeed in "thinking" occupations such as the science because their culture says it's a "white person thing". Thus their motivations and role models for success are directed more towards music and sports.
What are the current thoughts behind intelligence and race? | askscience | http://www.reddit.com/r/askscience/comments/ieekm/is_there_a_correlation_between_race_and/ | {
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"It turns out that there is an arguably large cultural bias on many of these intelligence tests, combined with confounding factors like low socioeconomic status (poverty) and minority status in the US. For this one specific test, there may not be doubt that there are differences (on average) between ethnicity groups - the incorrect part of the argument is that the 'racial' group is the *reason* for the higher/lower score.\n\ntl;dr there's no difference in actual intelligence just based upon race - many other factors get in the way and make it look like there are differences.",
"As with most social sciences, the difficulty here is separating your variables.\n\nWe know that race is correlated with socioeconomic status. We also know that nutrition, access to education, and culture biases play a role in the development of intelligence, and on performance on tests.\n\nSo even if you had a test definitively showing differences in IQ by race, it would be hard to link the result solely to race.\n\n*The Bell ~~Jar~~ Curve* is generally regarded as bad science, but it is very distressing how it was shouted down as a question science should not even ask. If we could isolate a physical mechanism to caused lower intelligence, and possibly cure it, we'd wind up with a lot of smarter people. ",
"_URL_0_\n\nthis seems to suggest that there is."
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6ostsb | why does baking soda help get rid if mouth ulcers? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6ostsb/eli5_why_does_baking_soda_help_get_rid_if_mouth/ | {
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"Baking soda is a base and often ulcers are irritated by the acidity of our saliva. So if you the baking soda with the saliva create a neutral environment for the sore to heal. "
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1u2f14 | What was Lenin's real nature in comparison to Trotsky or Stalin? | I had just begun reading Robert Gellately's *The Age of Social Catastrophe*, and in the introduction he notes the existence of a myth regarding a "Good Lenin"; he states that the Lenin that post-Stalin Communists and Socialists revere is a sham, and that Lenin's real nature was that of a merciless dictator. He goes on to note that the myth of the "Good Lenin" as the ideal of socialist/communist philosophies was only really invented by Soviet leaders wanting to distance themselves from the era of Stalin.
Gellately describes Lenin as a harsh user of terror on the people, and also goes to debunk the theory that he wanted to remove Stalin from the position of General Secretary by blaming it on a personal issue with Lenin's wife, and also notes that Lenin had no intention of removing Stalin from the Politburo and Central Committee.
Is what Gellately describes completely true? Was Stalin and his ways of terror a natural extension and expansion of what Lenin wanted? Did Lenin really favor Stalin over Trotsky? To what extent is the image of Lenin as a cruel dictator accurate, and how flawed is the idealistic image of him that some revisionist socialists have today? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1u2f14/what_was_lenins_real_nature_in_comparison_to/ | {
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"I would absolutely agree with the first part of his thesis: that Lenin was a brutal dictator and that the myth of Lenin being a good Bolshevik and Stalin being a bad Bolshevik is unsupported by evidence. Lenin clearly wanted to provoke a civil war in Russia, as documents uncovered since the opening of the Russian archives in 1991 have shown. This is because he knew that the Social Revolutionary and Menshevik forces in Russia would not support his violent overthrow of Alexander Kerensky's provisional government. Through both the Russian Civil War 1917-1921 and its accompanying Red Terror, Lenin clearly demonstrated the brutality and ruthlessness that characterized Stalin's regime. Lenin established his secret police, the Cheka, in December 1917, and formed the gulag prison camp system in the same month. Both of which were used to enact horrible terror and brutality on the Russian people. By 1923, over 500,000 people languished in gulag labor camps. In January 1918, Lenin had his Third Soviet Congress pass what was called the Loot the Looters Decree, whose intent was to annihilate Russia's middle and upper classes. Lenin also implemented his War Communism in 1918, an attempt to solve Russia's food crisis, but an attempt that ended in disaster and resulted in a horrible famine. Through all of this, it is clear that in many ways, Lenin displayed the same blindness to human suffering that Stalin did. From the Civil War and the Red Terror alone, I think one can reasonably claim that Lenin was indeed a ruthless and brutal dictator, just like Stalin. \n\nYet, I don't necessarily think that Lenin wanted Stalin to succeed him. I think one can claim that Stalin was in many ways a continuation of Lenin, as both used terror to achieve their goals. But Lenin was pragmatic, as his New Economic Policy of 1921 demonstrates. He was not completely blind to human suffering, as Stalin was. Not only that, but the postscript to Lenin's Testament of early 1923 shows that Lenin feared Stalin's place in the party because of Stalin's complete disregard for human suffering, such as the kind that Stalin displayed in the Georgian Affair of 1922. Not only that, but I think the relationship that Lenin and Trotsky had, especially through Trotsky's role as War Commissar in the Civil War, demonstrates that the two had a closer relationship that Stalin and Lenin.\n\nThus, to answer your first question, I think that to a major extent is the sympathetic image of Lenin incorrect. Lenin was clearly a brutal and ruthless dictator, who although pragmatic, was not afraid to use terror and civil war to accomplish his goals. And to answer your second point, I don't think that Lenin necessarily wanted Stalin to succeed him. Rather, he preferred Trotsky. Stalin's rule however does demonstrate that he in many ways continued what Lenin started. But I think that the poor relationship between Stalin and Lenin at the end of Lenin's life demonstrates that while Stalin did continue with the precedence that Lenin set, Lenin did not necessarily want this to occur.\n\nEven though Lenin did shift away from War Communism to NEP in the 1921, it's impossible to overlook the fact that Lenin was brutal and repressive and that the civil war and terror he used were very effective in guaranteeing his rule. Yet, I think this shift demonstrates Lenin's pragmatism, something that Stalin did not display. As such, I don't think that Lenin's late actions support the thesis that he wanted Stalin to succeed him.\n\nSources:\nA People's Tragedy: The Russian Revolution by Orlando Figes"
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2o1u9j | Tuesday Trivia | Never Done: Women’s Work in History | (The title of this theme is cribbed from [one of my favorite history books.](_URL_0_) And this theme definately wasn’t thought up while pissily doing housework.)
[Previous weeks' Tuesday Trivias and the complete upcoming schedule.](_URL_1_)
**What sort of work was done by women in your favorite time and place?** It can be about work traditionally done by women in that society, or it can be women doing work outside of their traditional purview (like maybe Rosie the Riveter stuff), or it can be how certain gendered work either switched which gender it “belonged” to, or became ungendered. Or any other interpretation of “women’s work” you can come up with is good really.
**Next week on Tuesday Trivia:** Siblings! We’ll be telling stories of historic siblings. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2o1u9j/tuesday_trivia_never_done_womens_work_in_history/ | {
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"Is today’s theme just an excuse for me to post a long winded ramble about my hobbies? Of course not.\n\nBut it’s time to talk about knitting and its fantastically understudied history. Knitting gets very little attention from “real” historians, its history and folklore was only passed orally for a long time, and today it is primarily discussed in pattern books, blogs, and forums. I know of a whopping TWO academic-ish history books about knitting. It’s a history you don’t think about unless you start doing it I think. \n\nI knit my share of junky modern stuff with fun-fur eyelash yarn and such, but I try to do some historic and vintage things because they make me feel a connection with women of the past that I really can’t get elsewhere, even from cooking historic recipes which I also like to do. (I suspect my foremothers would laugh at me feeling historical by making anything in my modern kitchen on my clean electric stove.) Knitting is kinda extra-historical because its largely unchanged from its murky invention, sure there are innovations, like the knitting machine, or those sweet rubber caps for the tips of needles so your stitches don’t slide off the ends, and the fun of superbulky yarns knit on needles [the size of Olive Garden breadsticks,](_URL_1_ ) but in the end hand-knitting is still just you making some fabric with 2 or more pointy sticks and some string. Just like people (especially women-people) did generations and generations before you. \n\nI’ll steal a quote from Franklin Habit who really sums up the appeal: \n\n > Whenever I work through an antique pattern, my thoughts inevitably turn to another knitter, long gone and utterly forgotten, who may have pursued the same course of knits and purls [...] Sometimes she’s an expectant mother puzzling over the Baby’s Hood, or a grandmother with a quiet afternoon turning out yet another Pence Jug. She may be called Ada or Isabel. She may live on the American frontier or in a London row house. She may be knitting under a tree, or beside a coal fire. She often, when confounded by the same vagueness in the pattern that confounds me, indulges in unladylike and possibly anachronistic vulgarities. (“Oh, @#$!% this @#%@^ nightcap,” said Aunt Ada.) ([source](_URL_0_), I’ve been meaning to make the Mrs. Roosevelt Mittens for like 5 years now.) \n\nAnother reason I am drawn to knitting is because [it was a skilled cottage industry for a lot of centuries, especially for Scottish women,](_URL_2_) who would be the bulk of my ancestors. Scotland in particular was known for socks and lacework. Knitting was a source of money people who otherwise couldn’t do any useful labor - it doesn’t require a lot of investment in materials (you just need needles and yarn), nor does it require physical strength, it could be done by people otherwise unemployable like the elderly or infirm, or just farming-people in winter. Another reason knitting is so lovely is because it’s a social or asocial activity as you see fit. You can knit in a group, you can knit with a friend, you can knit on the couch with your husband, or you can knit all by yourself. Many of the women who had to knit for money or to keep their family clothed [did that shit on the go](_URL_5_) between other work. \n\nMy favorite type of knitting is lace knitting, my goal is to someday make a Shetland lace [“wedding ring” shawl](_URL_6_), which is the pinnacle of a lace knitter’s art. But for the meantime I stick to simpler lacework. Like most knitters, I have a habit of buying yarn that I think looks really cool in the skein, getting it home, forgetting about it, and years later discovering some butt ugly yarn in my closet and then desperately trying to think of something to use it up on. [Here is my yarn of the moment](_URL_3_), a bulky weight dark purple mohair with a sparkle running through it, which I know must have seemed awesome at the time but now strikes me as compelling evidence that I have truly awful taste and should not be allowed to dress myself. It’s also itchy, and I had 8 goddamned skeins of this to somehow make into something acceptable. I decided on a lace wrap (as wraps/shawls don’t get too close to your body so the itchy wouldn’t be too bad). Mohair yarns’ fuzzy halo kinda “muffles” the visual impact of lace patterns, so I wanted a bolder, simpler lace that would still be visible through the eye-stunning fug of a sparkly mohair. I settled on [Old Shale Stitch,](_URL_7_) which is an old Shetland lace pattern. It’s actually really “Shell Stitch” because it looks like seashells but the early knitting pattern collectors didn’t speak Highland brogue so it got put down in the books as Shale. It’s the traditional edging on [hap shawls](_URL_8_) which are big wool shawls that would be everyday wear, so I thought I’d make my wrap something of an homage to those. It’s also an “unbalanced” lace (that doesn’t stay square as you knit up), so I thought the way it pulled itself into ripples was also kinda neat. \n\nSo, my husband was unexpectedly in the hospital for a few days 2 weeks ago, and when I rushed home after he was admitted I had a few minutes to gather some overnight stuff and then just anything to distract me, and I grabbed: a gay romance novel, a Tupperware container full of soynuts (I don’t remember what the thinking was on this one), and my knitting. And boy did that damn knitting just about save my life. I did not have 2 brains cells to rub together long enough to do any sort of reading so the book got left in my bag the entire time, but I think I knitted about 5 skeins in 48 hours. “I’m sorry about all the mohair!” I said to the cleaning staff as I shredded like a dog blowing coat, compulsively knitting in the guest chair. But that repetitive, productive movement of knitting gave me a comforting connection to countless women before me who had no doubt sat at many besides waiting to see what would become of their loved ones. Husbands have always gotten sick. Illness has always been fearful. And women have always worked through it. (And after all this I forgot to take a picture of the final product last night, I'll see if I can update with a photo when I get home.) \n\nAnyway he’s fine. After Christmas is done I think I’m going to make good on my threats and finally make him a historic [Scottish-pattern gansey](_URL_4_) and force him to wear it. \n\nAnyway, if you’d like to read about the history of knitting, here are the two books: \n\n* *A History of Hand Knitting* by Richard Rutt, from 1987 and EXTREMELY British \n\n* *Knitting by the Fireside and on the Hillside: A History of the Shetland Hand Knitting Industry c.1600-1950* by Linda G. Fryer, from 1994 and not so terribly British ",
"Sorry this is a tad lazy, but I've written on Chinese immigrant prostitution a few times in the past on /r/askhistorians, so I'm going patch together my previous posts on the topic. Excuse the lack of context, these were all answers to distinct questions that were not 100% about prostitution.\n\n > One type of Chinese slavery that did occur with more frequency, even after the passage of the 13th amendment, was the sexual slavery of Chinese prostitutes. As with anything, the individual quality of life for these prostitutes varied, but was of course abysmal. They were often beaten, abused, etc. The prostitutes came from China (typically southern, Cantonese-speaking provinces like Guangdong). They were usually lured over--either with trickery or outright kidnapping, made to sign a pretty malicious contract, and worked for somewhere around 3-5 years, during which time they were completely the property of the brothel owner, or \"pimp\" to use the modern-day terminology.\n > I am not aware of any black prostitutes in California at this time (though I'm sure they existed), so I can't speak to that. I can tell you that Chinese prostitutes had a better time within the Chinese community than white prostitutes had in the white community. The Chinese prostitutes were usually prostitutes due to family necessity--their homes in China couldn't take care of them, the family needed money, etc. The Californian Chinese community knew this, and thus treated the Chinese prostitutes not as \"dirty whores\" the way some white prostitutes were looked at, but instead as disadvantaged women, trying to do what was right for the family.\n\n.\n\n > In the earlier days of Chinatown, the Chinese quarter had a significant seedy underbelly, which had things like opium dens. One of the businesses more frequently attended by whites were the brothels. Rumors that Chinese vaginas were shaped differently than American ones led to the popularity of the \"ten-cent lookee\"--providing a cheap sexual outlet for young white laborers, sailors, et al.\n\n.\n\n > Because of the under-the-table nature of prostitution, as well as Chinese presence in general, it's hard to estimate how many women served a prostitutes. If we look at the numbers and err on the side of more prostitution, we can get a figure as high as 85% for the peak percentage of women serving as prostitutes (this number is specific to San Francisco). This percentage declined over time, as more women came and started taking the roles of housewives or even laborers and wage-earners.\n\nExcuse me for offering such a dismal portion of \"women's work\"!",
"While my post won't compare to Caffarelli's, my favorite time to study in history was WWII, and place would be Germany, the United States, and Great Britain. Most of us know how the role of Women changed in the United States and Great Britain with women moving into the jobs held by men because the men were all off fighting the war, as well as the women working industrial jobs due to the huge demand for heavy industrial products thanks to the war, but the change of roles in Nazi Germany for women is quite different, and very interesting. In Nazi Germany, women actually went away from the workforce and back to being housewives, a change rarely seen during wartime. Hitler saw no purpose or reason for women to work, and their main job was to take care of the house and MOST importantly, produce children. That is, only if they were of Aryan descent. Women deemed \"unpure\" that wouldn't be necessarily prosecuted under Nazi rule (so not jews, gypsys, etc.) but still deemed second class citizens because they were not of Aryan blood would sometimes undergo forced sterilization. To enforce this, all marriages had to be approved by local government officials, and if a member of the SS was seeking a bride, they potential bride had to undergo a very extensive background check to ensure they were \"worthy\" to marry and have children with Hitler's elite Aryan soldiers. This whole obsession over large families and motherhood started because in the 1920s Germany had the lowest birthrate in Europe, and this was viewed as a problem by Hitler because he thought a high birthrate meant a better chance at victory, not to mention he wanted future Aryans to continue conquest and to settle in what he envisioned as \"the thousand year Reich\" The Nazis declared mothers day a holiday and started giving gold cross awards to elderly mothers with lots of children. Although the award itself was not valuable and held little meaning, it was viewed as a prestigious honor and encouraged women to have children. This along with extensive state propaganda, and a plenitude of financial benefits to young women deemed worthy to have children made the German birthrate take off from it's extremely low point in the 1920s and early 30s. There was a sort of cult of motherhood in place, and it was very desirable and encouraged to have a large family. In fact, the term family was reserved for couples with four or more children. While this may seem off topic since the topic of this thread was Women's work and I discussed the birthrate and motherhood in Nazi Germany, it's really not as that WAS women's jobs in Nazi Germany. It was accepted that women and their fertility belonged to the state, and they owed it to the nation to have a large family. (If they met the standards of course). ",
"OMG, so I recently got a book about propaganda posters during the Cultural Revolution in China, and in it, there's a section about women as subjects, called \"women hold up half the sky\". I'M SO EXCITED TO TALK ABOUT WOMEN IN MY AREA OF HISTORY OMG YAYYYYYYYYYYYYY.\n\n(I know, I was really informal and rather unbecoming in my tone, but I've been excited to write this post all day, or at least since I saw this thread at eight this morning. Please forgive me for the informality of the preceding paragraph. I'll try to contain my excitement a bit.)\n\n\"Women hold up half the sky\" was a propaganda slogan that came into prominence during the Cultural Revolution in China. This was yet another way in which women's roles had been changed, continuing a tradition of redefining a women's place stemming from discussions on how to make China a stronger country in the 19th century.\n\nSome background. Women and their role in society has been a part of national debate and intellectual discussion since the late 19th century. Their status was linked to the country's prosperity and health (of sorts). Intellectuals came to believe that the Chinese woman, with her bound feet and her restrictions encoded in Confucian ideology, was a sign of China's backward nature. As such, it was believed that reforming or revolutionizing her status would lead to a stronger, more modernized China. Reforms included abolishing the concubine system, banning the practice of foot binding, educating women, free choice marriage instead of the arranged marriage system, the right to divorce, and encouraging women to take part in the political -- and outer -- sphere. Most of these early reform efforts were led by men, although some women did take part (both on the Nationalist side and the Communist side).\n\n(I'm getting rather off topic, but if you're curious about this topic, I highly recommend the book *Engendering the Chinese Revolution, Radical Women, Communist Politics, and Mass Movements in the 1920s* by Christina Kelley Gilmartin. The focus is on the Communist Party's gender politics, but there's a chapter in there that does discuss how the Communists and Nationalists worked together to advance women's rights during the First United Front of the 1920s.)\n\nAnyways, so the Communists come into power, brought about various reforms such as the Marriage Law of the 1950s and the land reforms (which allowed women to own land), etc etc etc. Now we get to the topic of this post: propaganda posters!\n\nThe Cultural Revolution had new goals for women, new roles. Women were being encouraged to take on traditionally masculine professions, to stop wearing feminine dress, and to otherwise help build a better Communist nation. For a woman to act more masculine is to lead revolution; being concerned with things like beauty and fashion were seen as bourgeoisie and otherwise *bad*. Because of this, many of the women depicted in these posters have short hair and are dressed in clothes that don't emphasize curves or the feminine form. Furthermore, attention wasn't being drawn to her because she was a woman, but because she was accomplishing tasks that would further state goals and lead to revolution and another new China. Whether she was working in the capacity of an agricultural worker, a student, an air force pilot, an electrical worker, a chemist, or more, she was furthering revolution. It didn't matter what her sex was; what mattered was whether she could do these jobs. And as these propaganda posters show, the Chinese Communist Party believed that she *could*. She held up half the sky, remember?\n\nThis time period saw the introduction of the Iron Girl, a woman who was able to take on jobs in heavy industry, construction, and agriculture alongside men. She was able to do the same work that the men did, and she did it well. She was the epitome of what an ideal woman should be during this time period: more masculine, equal in status alongside men, and holding her half of the sky. These Iron Girls were the subject of many propaganda posters, serving as a prominent symbol of the Chinese Communist Party's gender ideology during this period.\n\nHowever, when the Cultural Revolution came to an end, the Iron Girl served as a symbol on what was wrong with Party ideology prior to economic reforms. Femininity became an important trait again, with publications emphasizing that men and women were inherently different from one another. Instead of being held up to the standards of men, people during the 1980s believed that a new standard should be made for women to live up to, in order to account for this \"inherent difference\" between the sexes. (See: *Personal Voices: Chinese Women in the 1980s* by Emily Honig and Gail Hershatter, which discusses this topic at length).\n\n[For the curious, here's a small sample of posters from the time period (with apologizes in advance for using an iPod camera instead of setting up my scanner/printer).](_URL_0_) ",
"Once again I'll deal with some hockey history. This is about Marguerite Norris, the first woman to have her name engraved on the Stanley Cup.\n\nNorris' father was James Norris, Sr. Through a series of questionable business dealings that aren't relevant here, he had control of three of the six teams in the NHL when he died in 1952. To sort this out, his sons had to relinquish control over his initial, and favourite, team, the Detroit Red Wings. James' 24-year-old daughter Marguerite was named president of the team. Ostensibly this was done so the brothers, James, Jr. and Bruce, could exert control over the Red Wings; she was just supposed to be a figurehead.\n\nHowever that didn't work, and she took her job seriously, while ignoring her brothers. Already a strong team (they won the Stanley Cup in 1950 and 1952), the Red Wings won the Cup again in 1954 and 1955.\n\nBy this time the Norris brothers, and the GM of the Red Wings, Jack Adams, had had enough of a woman running the team, and worked to oust her. James, Jr., or Jimmy as he was known, sold his share of the Red Wings to Bruce in exchange for shares in the Chicago Black Hawks. This gave Bruce enough leverage in the Red Wings to appoint himself president of the team, demoting Marguerite to Vice-President, a largely meaningless role. With the Norris' still controlling three of the teams (and they would until the mid-1960s), the NHL was sometimes referred to as the \"Norris House League,\" and not in a positive manner (not that it helped; except for 1961, no Norris-controlled team would win the Cup again).\n\nMarguerite kept on with the team until 1957, when an abortive attempt by several players, including key members of the Red Wings, to form a players' union fell through. She opposed Bruce's reaction, which was to trade the offending players away, and resigned shortly after. Detroit would then endure decades of poor play and humiliation, and not win the Stanley Cup again until 1997 (the Norris family sold the team in the early 1980s).",
"Well, I had done a little prepping for questions about the role of women in the Spanish Civil War, and then no one asked about it in the AMA! So while it doesn't 100 percent fit, here is a bit I had already done a rough write-up of.\n\nViews on gender roles between the Nationalists and Loyalists were quite stark in their differences. Spain had been way behind the rest of the west in terms of women's rights, but the rise of the Republic in 1931 set the country on a crash course of liberalization - one of the major criticism of the Popular Front from the right prior to the war. By the mid-30s, Spain was at the forefront of women's liberation!\n\nIn the case of the Loyalists, progressive attitudes saw women not only being encouraged to work outside the home in in formerly male dominated jobs such as factories, but in some factions (especially the Anarchist CNT-FAI), women fought side by side with men in the militias as they battled the Nationalists. This would become less common however with the consolidation of forces under PCE (Communist) control later in the war.\n\nWhile the Nationalists did encourage women to contribute to the war effort as well, it was much more constrained within framework of traditional domesticity. The Auxilio Social, for instance, was a humanitarian arm of the Falange’s “Seccion Femenina”, and provided nursing and relief work for both soldiers and civilians in Nationalist controlled areas. Such work was only for young, unmarried women, and leaders made clear that a woman’s most important role remained in the home with her family.\n\nWith the defeat of the Loyalists, what changes had happened were quickly reversed. Women were back to being seen as mothers and wives, and lost the equality that they had briefly enjoyed. Spain would again fall behind the rest of the west - only women who were heads of households would be allowed to vote until the 1970s.",
"Well I'll shoot. Women had huge networks of seed exchange as part of the settlement of the west. Women would be all alone on these absurdly isolated farms and one of the ways they would keep materially in touch was exchanging seeds for various crops, vegetables, decorative plants, and flowers! It would be an incredibly difficult project, but someday when tenure is assured and/or I have tons of time, I'd love to travel the country digging through archives to compile a history of women's seed networks across the spreading US through the 19th to twentieth century!\nsighhhhh . . . . . . ",
"So this is one of my favorite stories. It's about a woman named Barira, who was a slave in Arabia in the early 600s. Her example became an important legal precedent for early Islamic scholars. The first scholar to organize stories about Muhammad into a collection of precedents for use by jurists (the *Sahih al-Bukhari*, c.840s) included the story of [Barira](_URL_0_) in 33 different places, suggesting just how important he thought it was.\n\n > Aisha said:\n\n > \tBarira had come to her seek help with her emancipation contract. She had to pay five ounces (of gold) in five yearly installments. Aisha said to her, “Do you think that if I pay the whole sum at once, your masters will sell you to me? If so, then I will free you and your *wala’* (loyalty) will be for me.” Barira went to her masters and told them about the offer. They said that they would not agree to it unless her *wala’* would be for them.\n\n > \tAisha continued: I went to God’s Messenger and told him about it. God’s Messenger said to her, “Buy Barira and manumit her. The *wala’* will be for the liberator.” God’s Messenger then got up and said, “What about those people who stipulate conditions that are not present in God’s laws? If anybody stipulates a condition which is not in God’s laws, then what he stipulates is invalid. God’s conditions are the truth and are more solid.”\n\nThis story doesn't tell us much about Barira's day-to-day work. Other stories about the life and sayings of Muhammad make it clear that some slave women worked as cooks, fortunetellers, household managers, prostitutes, shepherds, tanners, and wet nurses. Not all this work was licit, but Barira's example shows that slave women could engage in these or other types of work to earn their own money, and eventually to buy their freedom.\n\nWhat I think is even more interesting about this story is the opportunities taken by both Barira and Aisha (one of Muhammad's wives). Barira, a slave woman, negotiates and enters into a contract with her masters (i.e. she's partially owned by several different people). Aisha herself has access to what seems to be a substantial sum of money. Between the two of them, they negotiate not only for Barira's freedom, but they also establish who will receive Barira's *wala’*. This is an important relationship, similar to the patron/client relationships of antiquity, and it guarantees that Barira will still have someone obligated to provide for her once she's free. In return Aisha will receive a client obligated to support her, including providing food, hospitality, and requested services. And the hadith ends with Muhammad standing on a pulpit, affirming that these two women had the right to enter into such an agreement, purchasing Barira for manumission and clientage, even on the false condition that her *wala’* will go to her previous owners.\n\nSo although the story of Barira doesn't tell us about the particular labor that women were doing, it does tell us a bit about their legal personhood, their abilities to enter into contracts, and their abilities to accumulate and discharge wealth. Altogether, I think it's a very surprising precedent for what women should be able to do, set by none other than a slave woman laboring at the birth of Islam."
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2c55li | why do commercial airplanes board passengers using the seemingly inefficient "zone" system, rather than filling the seats chronologically? | It seems crazy to me from both a customer satisfaction standpoint, and an economic standpoint for the airlines (wasted turnaround time). It seems like they would both save money AND have happier customers, if they would just board passengers more efficiently. There have been studies (linked in comments) by mathematicians and economists, so why haven't they been adopted?
It seems like every time I fly, after a few minutes of boarding the entire plane is backed up waiting for 1 person to load their bags into the overhead bin. Even when I have a low zone number (board early), there are completely full rows much closer to the door than where I'm sitting.
I know people are probably averse to splitting up families during boarding time (to load windows to aisles, back to front, or something similar), but it just seems like the zone or block method has to be the most inefficient.
Also - what determines your zone number? If it's the order in which you purchased your ticket, as I've always suspected, I'm going to be even more baffled by the process.
There was a helpful [comment](_URL_0_) in a thread from a couple months back, but I am not convinced why some enterprising airline wouldn't even _try_ a different method to see how it works, and to show their passengers that they are trying to give them a better experience? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2c55li/eli5_why_do_commercial_airplanes_board_passengers/ | {
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"[This](_URL_0_) article from CNN implies that airlines are indeed doing some research in this area, maybe even testing. \n\nHere is a description of a [method](_URL_1_) modeled by Dr. Steffen, a physicist at Fermilab, which seems to cut boarding time roughly in half. ",
"Generally, the zones are based on where the seat is on the aircraft -- they fill back to front, with two important exceptions:\n\n1 - First/Business class board first.\n2 - Preboarding. Generally designed for very frequent flyers in coach, as well as elderly or people with small children, many people do preboard. And there's really no enforcement -- if someone feels they need extra time to preboard, then they will preboard. As a result, when the back-to-front zoned boarding begins, there are already people seated all over the plane.",
"There was research done into the fastest way to board a plane. The result? Completely random boarding.\n\nImagine passengers get in line to board the plane in perfect order from rear to front. The first person in line reaches the back of the plane and proceeds to load his bags in the bins. The passenger behind him must wait for him to finish because he is in the same row, same with the one behind him and so on. There are six people in the rear row but only one of them has reached the back of the plane. The entire line is now backed up. In this case *only one passenger* is actively in the process of boarding *the whole time*.\n\nNow imagine you line the passengers up randomly. Yes, you will get times where one person is blocking the line up at front, but now you will also get times where multiple people are boarding at a time because you have some mixes of people in the back and people in the front getting seated simultaneously. Make sense?\n\nEach zone has people from all over the plane to ensure a random mix of boarding throughout the plane as much as possible.\n\nI suppose if you could be perfectly ordered the best way to do it would be to line everyone with a left window seat rear to front, followed by everyone with a right window seat rear to front, followed by middle seats ect. Realistically the logistics of lining people up like this would just be impossible, especially because now you have to separate families and groups. Random is the easiest way to ensure somewhat efficient boarding.\n\nOne idea I have to slightly speed the process is to board all lone travelers with window seats first. Maybe that's just me being selfish :) though.\n\ntr; dr: Airlines researched the fastest way to board. Random (though it may seem counter intuitive at first) is the best answer."
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10xcdl | If the Earth is shaped like a pear does that mean atmospheric pressure at sea-level differs depending on latitude? | askscience | http://www.reddit.com/r/askscience/comments/10xcdl/if_the_earth_is_shaped_like_a_pear_does_that_mean/ | {
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8248hw | Henry VIII jousting in The Tudors | Good morning everyone.
I've recently picked up the show The Tudors and one thing that surprised me was Henry VIII 's jousting armor. It seems like there is nothing to protect the neck or the forearms in there.
Considering the dangers of having wood splinters all over the place, would people really go to jousting matches with so little protection?
Many thanks in advance. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/8248hw/henry_viii_jousting_in_the_tudors/ | {
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"Jousting armour typically had excellent neck and forearm protection. As you note, it would be very dangerous to not have it.\n\nOne example of one of Henry's jousting armours:\n\n_URL_4_\n\nI believe this is the armour he wore for jousting at the Field of the Cloth of Gold tournament.\n\nJousting armours could be field armours (i.e., armours intended for battle) with extra pieces of armour to provide more protection. On example of such additional protection is this *grandguard*:\n\n_URL_2_\n\nwhich was made for this armour:\n\n_URL_5_\n\n(among the 89 photos of this armour on that page, you will see some with this reinforcing piece, and other additional pieces, in place). The grandguard provides additional protection for the left shoulder and neck. The armour it is made for already has excellent neck protection. With this, it has even more excellent neck protection. The real-life Henry VIII would not have put up with the armour in the TV series!\n\nJousting helmets could also be made specially for jousting. For example,\n\n_URL_1_\n\nand\n\n_URL_0_\n\n(this type is often called a \"frog-mouth helm\").\n\nHenry VIII took his combat sports very seriously, and could afford the best in available armour, and his armours show this. Two further examples of this are this armour:\n\n_URL_6_\n\nand his \"spacesuit\" armour:\n\n_URL_3_\n\nwhich is remarkable for its thorough coverage of the insides of joints (which are often unprotected, or protected by mail \"voiders\" in field armours).\n\nEven with that superb protection, jousting was still dangerous. Henry VIII suffered a serious accident in a joust in 1536 when his horse fell on him, resulting in a leg injury and possibly a brain injury. The possible connection between the accident and his later tyranny has been discussed in various documentaries and web articles, but as discussed earlier, here, by u/rbaltimore in r/AskHistorians/comments/4i4e1w/was_henry_viiis_jousting_accident_in_1536_really/ and also elsewhere (e.g., Suzannah Lipscomb, *1536: The Year that Changed Henry VIII*, Lion, 2009, who points out that Henry was on the way to tyranny already), it doesn't seem likely. An earlier accident, in 1524, where he was hit in his helmet while his visor was up, has also been blamed (see Lipscomb)."
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4nfa7k | where do nicknames for enemy soldiers come from? | In the US the bad guys are "Charlie" in the UK they are "Jerry" I assume that other countries have similar names for enemy troops. Where do the names come from? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4nfa7k/eli5_where_do_nicknames_for_enemy_soldiers_come/ | {
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" > In the US the bad guys are \"Charlie\"\n\nNo they aren't. That specifically refers to Vietnamese forces in the Vietnam war. The Vietcong (VC) is \"Victor Charlie\" in radio speak. That's where the charlie comes from.\n\n > in the UK they are \"Jerry\"\n\nAgain, it refers to just Germans. Not just any aggressor. Jerry is just an abbreviation of German.",
"No. Each war gives a nickname for enemy troops unique to that war. It is normally related to the short hand for the country/governments of the enemy or it is a common name used by the culture of the enemy. \n\nThe Vietcong (communist Vietnamese) were called Charlie by the US because of the military alphabet \"victor charlie\" being VC. \n\nAll the English speaking world used \"Gerry\" pronounced Jerry for short hand for German. It is derived from the \"Ger.\" abbreviated form of Germany. \n\nThe Germans called Russians \"Ivans\" in both world wars. \n\nDuring the American civil war you had \"Johnny Reb\" for the South and \"Billy Yank\" for the North. As well as just \"Yankee\" and \"Rebel\" used. ",
"From WWI until now:\n**Pejoratives for enemy troops from whichever side the user is on**\n\nGermans- Fritz, Hun, Jerry, Boche (French), Kraut, Alleyman (from Allemand), Hans\n\nOttomans/Turks- Wog\n\nJapanese- Japs, Nips, Tojo\n\nBritish- Tommy, Limey, Les rosbifs\n\nFrench- Frog, Franzmann, Franzacke\n\nRussians- Ivan, Commie, Red, Bolshy, Russki\n\nSerbs- Jugos, Turks\n\nChinese- Slant-eye, Chink, Gook, Chinaman\n\nKorean- Gook, Commie\n\nVietnamese- Charlie, Gook, Slope, Zipperhead\n\nSomalis- Skinnies (unburdened_by_wit)\n\nAfghans- Raghead, Towelhead, Goatfucker, Haji, Muj motherfucker, Terry Taliban (Mr_Katanga) \n\nArabs- See Afghans plus: Ahmed, Derka, Camelfucker\n\nAmericans- Yankee, Gaijin, White Devil, Kuffar/Kaffir, Round Eye\n\n\nFeel free to add to the list if you see something or a whole people missing. Hope this doesn't get me banned.\n\n*Edit: Formatting",
"I see you getting a lot of examples of \"nicknames\" for the enemy, but let me tell you \"Why\" they happen in the first place. \n\nSoldiers have likely done this since the beginning of time and the real reason is that it serves the purpose of dehumanizing your enemy. It's logically easier to \"waste a gook\" or \"smoke a hadji\" than it is to kill a man. When combatants think about the other side as being human beings with mothers and children, killing them becomes tougher to reconcile than a stereotype. It is a very human coping mechanism.",
"It's usually derivations of the phonetic alphabet for the US.\n\nVeitcong = VC = Victor Charlie\n\nTarget = T = Tango\n\nJerry would be German, but more just a derivation of the initial consonant sound.",
"It derives from the enemies culture. Germans were called Krauts because it's a popular food in Germany. Japanese were called Nips because Nippon is the Japanese word for Japan",
"It depends on the war, who's saying it, and who they're describing. They're usually either an abbreviation, slang, and/or a pejorative. Oftentimes they describe a visible aspect of the enemy, such as ethnicity, uniforms, vehicles, insignia, etc. In certain cases, they would be considered racist today (and perhaps racist back then, but no one would have cared too much about that fact). Examples:\n\n*U.S. Civil War\n > North describing South: \"Rebels, Rebs, Dixies\"\n\n > South describing North: \"Yankees, Yanks, Feds, Federals, Blue Bellies\"\n\n*WWII\n\n > Americans describing Japanese: \"Japs, Slits, Meatball\"\n\n > British describing Germans: \"Krauts, Jerry, Hun\""
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1ld379 | what exactly fills up when computer memory is full? | When a computer, hard drive, mp3 device, etc is full why can't any more information be saved. I know there is a maximum amount of information that can be put on drives, but is it physical space or is it simply that the device cannot process more information? Very large drives that hold vast amounts of information are larger, so is physical space relevant at all or is that simply for more ram and computing power? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ld379/eli5what_exactly_fills_up_when_computer_memory_is/ | {
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"Imagine your device as a blank notebook. Now start writing all the 'data' or 'songs' down in the notebook. When it's full, so is your device. To put it as simply as possible. As far as the physical size of the device is concerned I'll go back to the notebook. As we get better at making notebooks we can make them with smaller and smaller lines allowing you to fit more information on each page. The more data per page the more info you can put in a smaller notebook. ",
"All storage on electronic devices is related to physical space. All data used by electronic devices is stored as either 0's or 1's. The 0's and 1's thing confuses many people right off the bat. By 0's and 1's, we actually mean sequences of binary states. What does this mean? Basically sequences of bumps, dots, magnetic fields, voltage states, or anything that can be read as either having, or not having. Think of Morse code. A short beep is a zero, a long beep is a 1. If we come up with systems to separate huge strings of 0's and 1's into numbers and letters, we can store data, like sounds, images, and text. Hard drives (for example) store these strings of 0's and 1's with a magnetic coating on the disk, which is sectioned into pieces for each 0 and 1. When you read files, a scanner moves along the spinning disk and finds whatever file you accessed, then it reads the magnetic field on the disk to assemble a series of 0's and 1's, and that's your file. Various forms of error correction are built in, so that even if part of the magnetic section is lost (disk gets scratched, etc.), the data might still be readable. So yes, the amount of space a device can store is related to physical space, but as technology gets better, we can make the space required to hold a 0 or a 1 smaller. Flash memory, which is what usb sticks/phones/music players use, stores the 0's and 1's in a special circuit board system which retains power even when unplugged."
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1nt5d0 | why do we use radioactive metals in nuclear power plants? | Why can't we just use like, iron, or something? Is it impossible to split the atom of a non-radioactive element? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1nt5d0/eli5_why_do_we_use_radioactive_metals_in_nuclear/ | {
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"We don't choose uranium and plutonium because they are radioactive. We choose uranium and plutonium because they happen to split easily when they absorb a neutron.....AND produce more neutrons when they split to continue the reaction on their own.\n\nYou can split just about any element, but most atoms will require you to put a lot of energy/effort into splitting them. "
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46hvu3 | If we ever get to do brain transplants, what would happen? Would the person with the new brain have the new brain old memories, or would all memories be forgotten? | Or... would he have he's old memories...?(I think thats impossible) | askscience | https://www.reddit.com/r/askscience/comments/46hvu3/if_we_ever_get_to_do_brain_transplants_what_would/ | {
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"**IF** it were ever possible, and that is a big if, you, and every conscious aspect of you, would be transported with your brain. Your mind is the product of the pink squish stuff between your ears. Move the squishy stuff around, and the mind follows.\n\nNow, there would be some things that would probably not be transported (at least to some degree), like certain physical skills that involved precisely timed interactions between muscles and the nervous system. But conscious memories? They're in your brain."
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2fkllu | I can't think of the name of painting, nor the artist, that I can write a perfect paper about. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2fkllu/i_cant_think_of_the_name_of_painting_nor_the/ | {
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3e6fp6 | What reasons made Justinian’s conquest of Italy take so long? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/3e6fp6/what_reasons_made_justinians_conquest_of_italy/ | {
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"The conquest of Italy started off well in 536 with the quick taking over of Sicily and then Naples after some resistance. Once Belisarius reached Rome however things slowed down. He entered the city unopposed but there were significant challenges in holding they city. Food first of all there was the issue of feeding the poplulation and secondly the wall circuit of Rome was enormous and the city itself had no gates. There was a one year siege of the city (537-538) which was successfully repelled.\n\nBelisarius eventually conquered most of Italy by 540 including Ravenna the capital.\n\nSo the initial conquest was only 4 years long but holding the gains would prove difficult and wars would last two decades. See this wikipedia article on the Gothic wars for more in depth information:(_URL_0_)\n\nCompared to the conquest of Africa where the Vandals had only two fortified cities (Hippo and Carthage), the Goths left the walls of the Italian cities intact and thus had more strongholds to retreat to and retaliate from.\n\nThe Goths also had allies such as Franks and Persians who would distract the empire and force resources elsewhere.\n\nLastly there is the problem of Justinian not trusting his generals' loyalties and splitting up armies in between them. The generals did not always cooperate either and at one point many just holed up in their own cities with their treasure and individually knocked out. [There is a fun little reference to this in computer science known as the byzantine general problem ](_URL_1_)\n\nLuckily we have great sources primary on this era thanks to Procopius's *Wars* and *Secret History* and his being present with the armies.",
"I would put most of the blame on Belisarius. Justinian's decree would have given North Italy (Po Valley?) to the Goths, which would have acted as a buffer state. The Empire would have acquired the rest of Italy at a point when the costs of operations was light. But Belisarius' disobedience of Justinian and treachery to the Goths galvanised resistance. Collins also point out that it's also possible Belisarius was going to accept the Western Emperorship but could not get support from his army, half of the officer of which did not trust him.* Procopius blames Justinian's jealousy of course, but considering a renew Persian War was looming and Belisarius was ordered to take over the Persian front and reinforce it with his Gothic captives, jealousy or not it was an incredibly sound decision.\n\nThe Goths elected Baduila (Procopius calls him Totila) a far more competent leader than the previous two Belisarius faced (the first one, Theodehad, it seems had be wholly incompetent), who went on the offensive with the empire distracted in the East. Belisarius returned to Italy later, but without adequate forces or the divergent campaigns of his first conquest due to the eastern needs, empire suffering from plague and economic down turn, and/or Justinian's jealousy and not trusting Belisarius anymore.\n\n**Early Medieval Europe* by Roger Collins."
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"https://en.wikipedia.org/wiki/Byzantine_fault_tolerance#Origin"
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1jebwg | How is it that different dogs breeds have specific personality types? | Everyone knows specific breeds are good caretakers, or good hunters, or aggressive etc. Is it a neurobiological thing? Or does it have to do with their hormone profile, or evolution maybe? | askscience | http://www.reddit.com/r/askscience/comments/1jebwg/how_is_it_that_different_dogs_breeds_have/ | {
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"Selective breeding by humans. If you want a good hunter then you breed the best hunters together, if you want a guard dog then you breed the animals that are more territorial. If you want a lap dog then you need to select the dogs that are less stressed by being around new and different humans. humans select the breeding animals for both desired form and temperament.",
"Like D_I_S_D says, the presence of certain personality traits in certain breeds of dogs have be purposefully selected for by humans in the creation of the breeds. But your deeper question of what causes the different behaviors is much harder to answer. In short, we don't know a lot about the chemical and genetic causes of personality or behaviors. There is a really cool effort happening right now to understand the dog genome, as a tool for understanding complex traits like personality in humans. Check out the [Dog Genome Project](_URL_0_) for a list of publications from this work. I have heard that they are including a survey on dog behavioral traits so that they can try to find the genes or regions of the genome that affect some dog behaviors."
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mnedq | How can animals sense danger and humans can't? | I remember seeing videos of animals going absolutely berserk before a catastrophe (e.g. Hurricane Katrina, Earthquake in Japan, etc.)
I know when a storm is about to approach because my dog starts to become afraid and goes and hides. Is it dealing with pressure changes in the atmosphere or something else that humans can't really sense?
[This is an example of what I am talking about](_URL_0_) | askscience | http://www.reddit.com/r/askscience/comments/mnedq/how_can_animals_sense_danger_and_humans_cant/ | {
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"Animals have adapted to react to a variety of sensory inputs that are associated with weather changes or imminent disasters.\n\nDogs can sense the pressure and humidity changes in the air with an impending rainstorm. You'd always hear old people say \"I can feel a storm coming, I feel it in my bones.\" They're feeling pressure changes **literally** in their bones (due to old age). \n\nAs for earthquakes, numerous studies have been done by the USGS (United Stated Geological Survey), but nothing substantial enough to make legitimate claims have been found. \n\nDogs can sense many things humans can't. They can detect certain medical issues before they happen, such as sensing hypoglycemia (diabetic condition) by feeling tremors and hyperglycemia (the opposite of the first) by smelling a ketone smell. Some dogs can sense seizures before they happen and alert their owners before they happen. Some dogs can even sense a myocardial infarction (heart attack) before they happen.",
"Actually, you do sense natural danger just like your dog does. However due to the fact that you will analyze and think about the issues at hand, you may just dismiss it as being silly or paranoid. \n",
"Animals have adapted to react to a variety of sensory inputs that are associated with weather changes or imminent disasters.\n\nDogs can sense the pressure and humidity changes in the air with an impending rainstorm. You'd always hear old people say \"I can feel a storm coming, I feel it in my bones.\" They're feeling pressure changes **literally** in their bones (due to old age). \n\nAs for earthquakes, numerous studies have been done by the USGS (United Stated Geological Survey), but nothing substantial enough to make legitimate claims have been found. \n\nDogs can sense many things humans can't. They can detect certain medical issues before they happen, such as sensing hypoglycemia (diabetic condition) by feeling tremors and hyperglycemia (the opposite of the first) by smelling a ketone smell. Some dogs can sense seizures before they happen and alert their owners before they happen. Some dogs can even sense a myocardial infarction (heart attack) before they happen.",
"Actually, you do sense natural danger just like your dog does. However due to the fact that you will analyze and think about the issues at hand, you may just dismiss it as being silly or paranoid. \n"
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1111w0 | why are you supposed to always add acid to water and never water to acid? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1111w0/eli5_why_are_you_supposed_to_always_add_acid_to/ | {
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"If water splashes up at you, it's not a big deal. If acid splashes up at you, it can be.",
"Water can absorb a great deal of heat. Acid, not so much.\n\nSo if you add acid to water, there's more water than acid. As the acid mixes into the water, it produces heat. There's plenty of water to absorb the heat.\n\nBut if you add water to acid--initially, at least--there's more acid than water. It can't absorb the heat, so the relatively small amount of water that you have only just begun to add to the acid has to absorb the heat, and there can be enough heat to boil the water, which can cause the acid to be splashed on you.\n\n*Always* add acid to water.",
"If you add water to Acid,acid is more than water and the temperature rises and could also splash onto your face.Or the test tube would melt due to excessive local heating.\n\n\nWhile adding acid to water,water is more than _URL_0_ the hot acid goes into the test tube and cools down in water and no splashing or excessive heating occur."
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4kfgyt | I know that the Civil War armies were said to make a miserable show to Europeans, but how did the Continental Army perform by European standards? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4kfgyt/i_know_that_the_civil_war_armies_were_said_to/ | {
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"Great question!\n\nThe answer to this will depend firstly on when in the way you're asking about, and secondly on what scale you grade an army's capabilities on. \n\nAt the start of the war, the Continental Army was, by almost every standard, terrible. The army that amassed outside Boston and later fought around New York City had poor officers, little discipline, uncertain supplies, and a patchwork of enlistment contracts that made its size unpredictable at best and doomed to extinction at worst. While the army won at Bunker Hill, that was more a testament to Gage making the wrong decision (a frontal assault), then lacking the manpower to launch a flank attack. Around New York, the Continentals were repeatedly outfought bad outmaneuvered by the British and Hessian armies, even in the wooded and broken terrain that was supposed to favor American troops. In one of the war's most catastrophic defeats, poor command and control of the army led to a force of 3,000 Americans staying in Fort Washington well after the position should have been abandoned. A Hessian assault force captured this garrison, and and an even more valuable cache of supplies, in one afternoon with minimal casualties. \n\nEven in the early years of the war, the Continental Army showed signs of promise. Knox's transport of 200 cannon from Fort Ticonderoga to Boston during the winter of 75-76 was a master stroke that effectively created the army's artillery branch in one go. Patriot troops captured Montreal and nearly seized Quebec in a daring and difficult winter campaign. Individual units fought well during the New York campaign, and American troops consistently demonstrated the ability to rapidly build large fieldworks. Washington's winter campaign in 76-77 saw a hardened core of veteran survivors of the Battles of New York surprise and out-maneuver well-commanded British forces in Southern New Jersey, doing permanent harm to the British war effort by making them look unable to hold territory the conquered or to defend the loyalists who publicly opposed the rebellion. Continentals stalled and swarmed a British attack towards Albany in the Battles of Saratoga, while Americans managed to make fighting retreat d at the Brandywine and Germantown I that fall of 77. \n\nBetween 1778 and the end of the war in 1783, the Continental army got more technically proficient as it professionalized. The Continentals fought the best units of the British Army to a draw on the open field at Monmouth, made successful night attacks at Stoney Point and Yorktown's Redoubt #10, and demonstrated incredible resiliency in the \"fight, get beat, get up and fight again\" chase across the Carolinians. At Yorktown, the Americans laid an exceptionally smooth formal, conventional siege, arguably the defining trait of military craft in the 18th century. \n\nWhy, then, do I still have reservations about calling the Continental Army good? First and foremost, their performance was inconsistent. Gates bungled the Battle of Camden in catastrophic fashion. While Morgan and Greene did led Cornwallis on an epic chased across the Carolinians, they could not stop him from invading Virginia, freeing thousands of slaves, and nearly capturing Thomas Jefferson as he fled off his plantation. \n\nMost importantly, the Continental Army grew increasingly mutinous in the latter half of the war. Between 1780 and 1783, the Pennsylvania Line mutinied twice abs the New Jersey line once in situations that stretched for days and resulted in some loss of life. Connecticut troops rioted in their camps at Morristown and West Point. The officers of the army gave some support to a plan by one of Gates' aides to march on Congress if they weren't guaranteed pensions. \n\nIn short, if I were drafting an army for a fantasy league of 18th century empires, I would not take the Continental Army. Their greatest victories involved either surviving defeat or substantial French assistance. They frequently seethed with discontent, as mutiny never seemed far away for both Continental soldiers and their officers. \n\n**Sources**\n\nMartin and Lender, *A Respectable Army*\n\nFischer, *Washington's Crossing*\n\nNiemeyer, *America Goes to War*",
"Follow up: Why was it said that the Civil War armies made a miserable show compared to European armies? I thought the Civil war is considered one of the first \"modern\" wars."
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dvr30j | what is a cocaine analogue? | Hi Everyone!
I work in a Nuclear Medicine department in a hospital. We use Ioflupane (Otherwise known as DaTSCAN) as a means to diagnose Parkinson’s Disease. Ioflupane is a cocaine analogue.
My question is: Why does ioflupane not cause the same effects as cocaine in patients if it is a cocaine analogue?
Thanks! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dvr30j/eli5_what_is_a_cocaine_analogue/ | {
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"It means it acts on the e.g. brain receptors or whatever it is you're interested in, in the same way as cocaine does without all the other effects. Usually such analogues either take cocaine as a starting point for their synthesis or have a synthetic component very similar to part of the cocaine molecule.",
"An analogue is just a compound that has a similar chemical structure to the one of interest. \n\nCocaine bind to a receptor on dopamine neurons in the brain called Dopamine Transporter (DAT). Normally, DAT transports dopamine back **inside** the neuron. However, when cocaine binds to DAT, it prevents DAT from working. ie. DAT leaves dopamine neurons out in the synapse where they are still active. This excess of dopamine alters perception; therefore, cocaine is *psychoactive*. On the other hand, Ioflupane can fit into and bind DAT but it does not inhibit DAT's function very much at all. Therefore, Ioflupane is **not** psychoactive. \n\nFor an analogy, \n\nImagine you drive a Honda Civic (the honda civic is DAT, which cocaine & its analog, Ioflupane bind to). **Your** key to **your** car (cocaine) turns fits in the ignition **AND** starts the car. If you got someone else's key from a different Honda Civic (Ioflupane) it would fit in the ignition BUT it would **NOT** start."
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1smota | What are the actual bytes made up of in a computer? | Also bonus question: What is the difference in how data is stored on a HDD as opposed to SDD and how does a computer read it? | askscience | http://www.reddit.com/r/askscience/comments/1smota/what_are_the_actual_bytes_made_up_of_in_a_computer/ | {
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"That depends entirely on the type of medium. On a mechanical harddrive, those bits are magnetic. In RAM or within the CPU, they're represented by electrical currents or charges. Data could be written to paper as visual or physical data if someone chose to. The list goes on. Ultimately, \"bits\" are just an abstraction of whatever medium that's been chosen to represent the binary data.\n\nMechanical harddrives store the data magnetically. The data is 'converted' from an electrical to magnetic charge when being written (and vice versa when being read). SSDs use completely solid-state chips to store the data. The type of chips and arrangement allow for the device to store data when powered down. These are pretty big simplifications, but that's the general idea of the differences.",
"They are stored as either an electric or magnetic field depending on the type of memory. a bit (1/8th of a byte) in RAM for instance is stored as an electric field and hard drive memory (the platter type) is stored as a magnetic field. SDDs are a similar technology to RAM."
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9qyyre | Is the ethical debate over killing and farming animals only a recent thing? Or did it span back further? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/9qyyre/is_the_ethical_debate_over_killing_and_farming/ | {
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"Related question, how and when did the practice of vegetarianism and similar diets go from being associated mostly with religious asceticism to being a non-denominational choice based on animal rights? Basically, if ancient arguments for vegetarianism were that it was unclean or sinful, how did that turn into the modern argument that animals should be respected as sentient creatures?",
"Although there are some of the probably older traditions around the world (like ancient Indian jainism, which advocated a path of non-violence towards all living beings, animals and humans alike) I'll limit my answer to ancient Greek philosophy – field of my academical interest.\n\nWe'll start with Pythagoras (Samos, c. 570 – c. 495 BC), presocratic philosopher who, same as Socrates, didn't write down his thoughts, but had a faithful bunch of students and followers to whom we own his historical record. Dicaearchus (Aristotle's pupil) wrote how Pythagoras': „most universally celebrated opinions, however, were that the soul is immortal; then that it migrates into other sorts of living creature \\[...\\]“\n\nNow in this, his doctrine of the transmigration of souls (*metempsychosis*), lies bio-ethical stance on killing animals. For one more example of the metempsychosis doctrine we can observe quote from Empedocles (c. 490 – c. 430 BC): „For already have I once been a boy, and a girl, and a bush, and a fish that jumps from the sea as it swims.“ \n\nThe important part of this doctrine is that it *proclaims personal survival of bodily death.* By Xenophanes' writing considering this context, Pythagoras even recognized the dog as one of his late friends. Now, if I held this opinion, we can see how easy it would be for me to defend non killing and farming animals – how can I eat a chicken, if there's possibility that that chicken was my mother?\n\nBoth Empedocles and Pythagoras were vegeterians. By Empedocles' surviving fragments, which are concerned with „not killing living creatures“, we learn that we are enjoined to abstain from „harsh-sounding bloodshed“, to avoid sacrifice and moreover, we must not eat meat, beans or bay leaves. As explained, the sheep you slaughter and eat was once a man, and once, perhaps, your son or your father. That said, to avoid patricide and filicide you must avoid all bloodshed. \n\nPythagorean school was an interesting mix of philosophy and mysticism, with an unique set of rules, such as not taking roads which public uses (out of fear of being defiled by the inpure, as Aristotle explains), dietary restrictions, vows of silence for new initiates, etc., and I encourage you to read further on this funky crew.\n\nFor now and to conclude, let's jump few centuries forward to confront Empedocles and Pythagoras with Aristotle. Aristotle (384–322 BCE) assigned to men and animals the faculty of sentience (capacity to suffer), but which gives men a title to moral consideration. That means animals don't have rationality or moral qualities which could match ones that we find in humans. He argued how plants are created for the sake of animals, and animals for the sake of men. What he did is establish some sort of hierarchy, taxonomical categorization - *scala naturae* (or Great Chain of Being) and at the top of that chain are masters who are gifted with rationality – men.\n\nAs we can see, Aristotle's position that humans and animals create two opposite moral circles, one rational and one non-rational is directly clashed with Pythagoras' and Empedocles' stance. To further this ancient debate, Aristotle's pupils, Theophrastus (c. 371 – c. 287 BC) argued also for vegeterianism, as he tried to explain how animals can feel same as men do and thus killing them is morally wrong. These are the beginnings of the ethical debate of killing animals in Western philosophy, and further thinkers followed in next centuries – Seneca, Plutarch, Plotinus and Porphyry, to name ancient Roman ones, for example.\n\n & #x200B;\n\n**Sources:**\n\n & #x200B;\n\nJonathan Barnes, *The Presocratic Philosophers*, Routledge, 1979.\n\nTerence Irwin, *The Development of Ethics: A Historical and Critical Study*, Oxford, 2007.\n\n*Historia Animālium*, Aristotle\n\nRobert Audi, *The Cambridge Dictionary of Philosophy*, Cambridge, 1999."
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2ih061 | what led to the end of people's beliefs in mythology as a religion? | EDIT: Specifically, Greek Mythology (e.g. Zeus, Hera...). To say that the vast majority of religions today are based on a mythology doesn't really answer the question. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ih061/eli5what_led_to_the_end_of_peoples_beliefs_in/ | {
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"That never happened. The vast majority of religion today are based on a mythology. Abrahamic mythology is still very prevalent today as organized religions. The Garden of Eden isn't any different than Pandora's Box or Thor crossing the Bifröst. The religions around some mythology's simply died out as other religions converted people. ",
"Mythology is just what you call a religion that doesn't have many active followers in the modern world. Christianity, Islam, Hinduism and all of the others can be called \"mythology\" exactly the same as Egyptian, Greek, Roman or Norse beliefs.",
" > Specifically, Greek Mythology (e.g. Zeus, Hera...).\n\nYour uneditable title is very misleading, and although I don't have an answer for that specific case, I'm quoting this here to point people at your true question, which is about the **greek** mythos in particular. ",
"They were supplanted by new beliefs, through various means. For example states giving funds, resources, and legal backing to strengthen the messages of new belief systems, like the Roman empire adopting Christianity, persecution of those who held onto old belief systems, assimilation of old belief systems into the new system, and so on.",
"The end of classical Greco-Roman religion can be mainly attributed to the rise of Christianity. Once the first few centuries AD had set in, paganism/polytheism were often persecuted, and people gradually made the change. I believe the last few groups who worshipped the Greek gods converted or died out by the end of the first millennium AD.\n\nStill, I should point out that your title is poorly worded. Not only are there many ancient religions that we currently study as mythology (Greek, Egyptian, Norse, Etruscan, and Celtic, to name a few), but you're conflating the words \"mythology\" and \"religion,\" which are two different things.\n\nMythology: the stories developed by a culture to explain nature, customs, and history\n\nReligion: a collection of beliefs, cultures, and morals that relate humanity to some sort of reason or order for existence.\n\nBy these definitions, even modern religions like Christianity, Judaism, Islam, Hinduism, etc, can be said to have, at their core, a specific \"mythology,\" and that term shouldn't be taken offensively, as though it's belittling or invalidating people's beliefs. It's just the word to describe their explanations for the history and physical rules of the world.\n\nSource: Minored in (and briefly double majored in) Classical Civilizations/Mythology). Plenty of ancient religions and modern religious studies credits.\n\nEdit: Added my source.\n\n",
"I think there is a common misinterpretation of the word mythology, due to it's association with \"Greek Mythology\" or \"Egyptian Mythology\". \n\nFrom wikipedia: Mythology can refer either to the collected myths of a group of people—their body of stories which they tell to explain nature, history, and customs—or to the study of such myths.\n\nWith this definition in hand, one could define the collection of Christian or Islamic beliefs as \"Christian Mythology\" or \"Islamic Mythology\". Beliefs evolve over time and are slowly swallowed up by other religions. Hinduism is a religion that did an excellent job of this, which helped it to spread. Christianity adopted many of the beliefs of Zoroastrianism and Manichaeism such as the belief in a \"end of days scenario\", otherwise known as eschatology, and the Saoshyant, or savior figure. \n\nI'm no expert, but Greek \"mythology\" was probably left behind as more and more people adopted more popular religions. The religion of the Egyptians was probably in conflict with those of their frequent conquerors: The Hyksos, the Kushites, the Assyrians, the Macedonians, the Ptolemaics, the Romans, etc. \n\n"
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o4rli | Why does gravitational potential start at zero and become infinitely negative? | askscience | http://www.reddit.com/r/askscience/comments/o4rli/why_does_gravitational_potential_start_at_zero/ | {
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"Potential energy is relative, not absolute.\n\nOne way of saying it is that you define where your zero point is and that becomes your reference.\n\nAnother way of saying it is that the you are really looking for a potential energy **difference** (Delta-U).",
"Well it doesn't necessarily start at zero. Only gradients of potentials are observable, so potentials are defined up to a constant. A point of reference if you will. However, your potential starting at zero is just a very useful choice!\n\nNow why does it become infinity negative? Well let's say we have a very small mass point particle at infinity, not moving (so its energy is zero), and some other very massive point object that the first will be attracted to. As it starts moving, its kinetic energy will increase, but its total energy has to remain zero because energy is conserved. So the gravitational has to be negative for it to balance out. As the particle gets close to the large mass, its kinetic energy growth without bound (becomes infinitely positive), so its gravitational potential energy must become infinitely negative."
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3vk9nm | if nothing can exceed the speed of light, how can we measure something as being 10,000 light years away without it taking 20,000 years to measure? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3vk9nm/eli5_if_nothing_can_exceed_the_speed_of_light_how/ | {
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"If we were measuring the distance with something like a laser range finder, that would be true.\n\nObviously nobody measure the distance to such far away object be pointing a beam at them and waiting until it gets bounced back.\n\nThis method is actually used with close by objects like the moon where astronauts left some mirrors just for that.\n\nIn astronomy however many interesting object are far to far away for this to work. So other methods are used.\n\nOne for relative close by object is measuring the stellar parallax.\n\nYou know how you can hold a thumb up and close your left and right eye alternatively and have the thumb move left and right against the background.\n\nIf you stay awake in math class and learn trigonometry you can use the distance the thumb appears to move to calculate the distance of objects in the background.\n\nThe same works in astronomy but the left and right eye is our earth travelling half a year around the sum and instead of the thumb being a fixed distance we have the really far away stars as 'fixed' and calculate the distance of more nearby stars by comparison and how much they move back and fourth against the background.\n\nThat is why the unit parsec (for parallax arc second) is sometimes used instead of the similarly sized light-years for such distances.\n",
"A lightyear is a set distance. If we know how many miles away something is, we can use the speed of light to figure out how many lightyears it is. \n\nBefore we knew how far the Earth was from the sun, everything in space was set at a relative scale. We said \"the earth is 1 Astronomical Unit away from the sun\" and used geometry to figure out the relative distances of the rest of the planets. We couldn't convert that to miles until we had two people in different countries observing a planet's position relative to stars. We knew how far apart the people were in miles, and with the geometry of parallax, we then learned how many miles were in an astronomical unit. \n\nAside on how parallax works: hold your arm straight out in front of you. Close one eye and use your thumb to block something. Now don't move your arm, but switch eyes. Notice how things seem to jump? That jump is related to the distance between your eyes. Put two telescopes at a known distance. Your thumb represents the star you're trying to measure. The background object represents background stars that are so far away, they don't appear to move.\n\nWhen parallax stops working, astronomers have different methods. Measuring spectral lines is one of them. Basically, we know stars have a lot of hydrogen. This means that they produce a lot of extra light at very specific wavelengths. This spectrum gets shifted around, but the relative position of the lines remains the same. If we can figure out which lines are which and how much they've been stretched or shifted, we can figure out (1) how far a star is, (2) whether there are actually two stars moving around each other, (3) if the light is from a single star or a whole distant galaxy, and much more. ",
"The light scientists use to observe distant astronomical objects is light which was emitted a very long time ago; if it's 10,000 light-years away, they observe light that is 10,000 years old. The scientists did not shoot a beam of light at the object, they're observing the light which is already there.\n\nIn order to determine how far an object is, scientists use a whole series of tests, depending on the distances involved. For relatively near objects, (such at those within 10,000 light years) they use parallax, a technique you can actually try out for yourself. Hold a finger up a few centimeters in front of your nose, and then look at it with only your left eye, and then only your right eye. The fingers seems to move back and forth as you switch from eye to eye, yes? This is because your eyes are not in the same place; they need to look at different angles in order to see the finger (this is true of all objects you look at, but the effect is most noticeable with something right in front of your nose). If you were to measure those angles, and the distance between your eyes, you could construct a triangle using those measurements, and figure out the distance from you to the finger using simple geometry.\n\nScientists do the same thing to figure out the distance to stars and other objects. Of course, astronomical objects are much too far away for you to be able to do the one-eye-at-a-time trick; instead, what they do is measure the object's position in the sky at one point on Earth's orbit, and then measure it again when they're on the opposite side of the orbit. Since we know how big earth's orbit is, we now have two angles and a side, and can use geometry to work out how far away the star is.\n\nOf course, this doesn't work for objects which are very far away; past a certain point, even our most precise instruments aren't able to detect the change in position from one side of orbit to the other. Fortunately, Astronomers have other methods they can bust out when working on those sorts of distances. For more details, I suggest reading [this article](_URL_0_) which describes them in significant depth, without being TOO overwhelmingly technical."
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3mgqp5 | what happens to food when exposed to air that justifies having a "consume within x days of opening" date? | My bottled smoothie has a shelf life of 4 months, but needs to be consumed within 24 hours of opening.
What happens when it comes into contact with air that doesn't happen during production? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3mgqp5/eli5_what_happens_to_food_when_exposed_to_air/ | {
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"Air has bacteria in it. Smoothies are great environments for bacteria to live in. Once it's opened, the number of bacteria will rapidly become high enough to threaten your health (and the taste of the smoothie). \n\n"
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3g8j76 | kernels (computing) | I hear they're important, but I've never heard a good explanation of them. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3g8j76/eli5_kernels_computing/ | {
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"A kernel does all kind of commonly needed stuff for you:\n\n* interacting with hardware and provide a standardized interface (so you don't have to write separate code for - as an example - each different sound card in each program that wants to use sound)\n* make sure your programs don't mess with each other, like overwriting each others memory\n* providing mechanisms for controlled communication between programs and components (eg. your program wants to send a message to the notification area, which is another program)\n* other useful functionality (getting random numbers, implementing common communication protocols, and so on)",
"A kernel standardized interacting with hardware. \n\nFrom a programmers perspective all you normally see is read, write, open, close. While in reality all these operations work on tapes, CD's, DVD, thumb drives, hard drives, and TCP/IP connections. \n\nAll of these devices are different. Have different physical jobs, and different standards. The OS manages that for you.\n\nAt the same time it manages memory, CPU clock frequency, power saving, task switching, and library loading. \n\nThese things are done to save the programmer time. So you don't have to worry about what device your talking too.",
"The kernel is the heart of an operating system. The most basic kernel does very few things. It manages and restricts access to memory, it manages processes and threads, it manages communication between processes, and controls access to the disks.\n\n1) Memory access. In order to run more than one program at a time, you need to have space in memory set aside for each program to use. Each program needs to be restricted to using it's own space in memory, and *only* it's own space. If you don't do this, badly behaving programs will damage data from other programs. Commonly, each program won't even know the memory used for other processes exists.\n\n2) Process management. In order to run more than one program at once, you need some code to keep track of all the programs, and to schedule time for each of them to use the processor.\n\nIn most desktop and server operating systems, this is done in some semblance of fairness, allowing each program to request time on the processor, and rotating through each program in turn to give roughly equal access to each, though a process can give up some of it's time voluntarily.\n\nThere are other ways to do this, like real-time computing, which allows programs to request hard deadlines, a time that they *must* be finished processing by. This is often used in some kind of control system, where the computer must take input, and process it quickly enough to respond to whatever is happening in the real world.\n\nThere's also the fact that most modern computers have more than one processor available. This can allow programs to split themselves into multiple pieces that are more or less independent, in order to run in parallel to each other. Making sure that programs actually gain performance out of this takes some adjustments to how you schedule processes.\n\n3) Communication between processes. Often, programs will be divided into smaller units that perform some task, and then hand a result off to another part of the same program. Or you want to be able to take advantage of multiple processors available, and run some of your code on each. Or your code uses some standard library or device driver in order to perform a standard task, or to talk to some piece of hardware.\n\nTo split your code into multiple processes, you need a way to communicate. In kernel land, this mostly takes the form of semaphores, pipes, message queues and shared memory.\n\nSemaphores let two or more programs control how they execute in relation to each other. It's essentially a flag that each program can raise and lower to let the other process know they've reached some specific point in their code. They're commonly used to let parallel processes share some common resource without stomping all over the other processes using it. If the flag is up, one program is using it, and any other programs using the same resource shouldn't touch it until the flag goes down.\n\nPipes are common in the Unix based world. They take the output from one program, and feed it into another. Usually, they're very temporary, only existing long enough to transition from one program to another.\n\nMessage queues are used for longer term communication. One program can put data into a queue, and when another related program gets it's turn on the processor, it can read from the queue. Messages stack up in sequence, so the reading program reads them in the same order they were sent.\n\nShared memory is actually just a careful breaking of a concern from 1). Normally, each program should be kept separate in memory, so they don't stomp all over each other. But, if they want to communicate large pieces of data, the kernel can set aside another piece of memory that they both have access to. Each program can read and write to this spot in memory when it's their turn.\n\n4) Disk access. Programs need to have access to disk, and while it's less critical than memory and processor time that it's shared equally, you also don't want programs stomping all over each other's data.\n\nThe more important point is actually that disk access is slow. In computing time scales, it's glacially slow. It's so slow that it would be a really stupid idea for the processor to be idle while waiting for a response to come back when it could run through a few more turns for other programs in the time it would have just been sitting there.\n\nThe kernel controls this. When a program requests disk input or output, it will send the request off to the disk, then put the program in a waiting state. When the response comes back, it triggers an interrupt, a special circuit in the processor that stops everything and loads up the kernel to process the response. The kernel then loads whatever program was waiting for the response, and lets it finish what it was doing as if the processor *was* sitting idle instead of letting other programs cut in line.\n\n---\n\nYou'll notice that all of these functions for the kernel have something in common. They're all about letting you run more than one program at a time. Before we'd written any operating system's and kernel's, running one program at a time is just how using a computer worked. You'd manually load a program into memory, manually start it processing, and the computer would do only that one thing until it had finished and gave you some output.\n\nAlso, it should be pointed out that modern kernels do more than just these four things. They typically come with all kinds of additional tools to make writing programs easier. A modern kernel is a one-stop shop for every programming shortcut you might need.\n\nBut, if you wanted to write something that would be called a kernel, at a minimum, you'd want it to do these four things."
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6lcr5e | When did people start calling themselves "Italians" and "Germans"? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/6lcr5e/when_did_people_start_calling_themselves_italians/ | {
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"[This question came up about a year ago](_URL_0_), although it's a good question that can certainly merit more discussion.\n\nFor Italy, the short answer is, \"When Napoleon crowned himself King of Italy.\" Prior to then the concept of an Italian language and culture was solely the purview of a small intellectual elite, who would have nonetheless identified more with their local identity more so than a common one spanning the whole peninsula. "
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2shkpc | In the second world war, was there ever an incident of a ship being captured by one side, then pressed into service for use against its former operator? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2shkpc/in_the_second_world_war_was_there_ever_an/ | {
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"The IJN used several ships captured from the British, Dutch and Americans as convoy escorts. These weren't captured in the traditional sense - they were never boarded. Instead, they were scuttled in port by their former owners when capture of the port seemed likely. The Japanese would later salvage them, and press them into service against their former owners. \n\nThe RN lost two ships in this way. HMS Thracian was on station at Hong Kong in December 1941. She remained at Hong Kong to provide fire support to the garrison, while the remainder of her squadron left for Singapore. She was scuttled after being heavily damaged by Japanese aircraft. She would be refloated in July 1942, and operated as patrol boat PB-101. She was recaptured in Yokosuka in 1945, and scrapped in 1946. The river gunboat HMS Moth would also be captured at Hong Kong, and operated on inland waterways in Japanese-occupied China. \n\nThe USN lost six ships in this way. USS Stewart, a Clemson class destroyer, fled the Philippines, and operated with ABDA forces in Indonesia. Heavily damaged after the Battle of the Bandung Strait, she was put into a floating drydock in Surabaya. She was not repaired before Java fell, and the drydock was scuttled with her inside. She was raised in 1943, and put back into service as PB-102. She would also be recaptured at the end of the war, and sunk as a target in 1946. The minesweeper USS Finch, fleet tug USS Genesse and Philippine customs vessel Arayat would be captured in Manila in various states of repair. They would enter Japanese service as PB-103, PB-107 and PB-105 respectively. Two gunboats, the USS Wake and USS Luzon were also captured, and put into service as the gunboats Tatara and Karatsu. Tatara fulfilled a similar role to the ex-HMS Moth, while Karatsu operated in the Philippines. PB-107 was destroyed by American carrier aircraft in Manila Bay at the start of November 1944, while PB-105 would be sunk by PT boats at the end of the month while escorting a convoy near Leyte. USS Finch would be sunk by aircraft from TF-38 while escorting a convoy off Vietnam in January 1945. Four Dutch ships were also captured, including one destroyer and three patrol boats. Another ship, the minesweeper Regulus, would be captured while under construction.\n\nWhile purpose built warships were repurposed, in some cases merchant ships could be reused. The first escort carrier was built by the RN on the hull of a merchant ship captured from the Germans. The banana carrier Hannover was captured in the Caribbean in 1939. She was operated by the Merchant Navy until January 1941, when she was selected to become an escort carrier. She was the first to enter service, being commissioned in June 1941. She was renamed HMS Audacity in service. Audacity would operate with the RN for 6 months, escorting convoys to Gibraltar. Her fighters claimed 7 German aircraft before she was sunk escorting convoy HG76 by U-751.\n\nSources:\nTabulated Records of Movement for the Japanese Navy, available at [_URL_1_](_URL_0_) - look under the sections for escorts and gunboats.\n\nThe Fleet Air Arm Handbook 1939-1945, David Wragg, 2003, Sutton Publishing."
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2uunfv | If one were to throw a magnet at a metal object, would it accelerate before it hits the metal? If so, where does the change in kinetic energy come from? | askscience | http://www.reddit.com/r/askscience/comments/2uunfv/if_one_were_to_throw_a_magnet_at_a_metal_object/ | {
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" > would it accelerate before it hits the metal?\n\nYes, it would. The extra kinetic energy comes the potential energy that was stored in the system due to two magnets between positioned at a distance from each other."
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6wkps8 | according to data we have discovered 14% of all organisms on earth. where does this number come from, if the other 86% of haven't been discovered yet (and therefore we don't know if they exist)? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6wkps8/eli5_according_to_data_we_have_discovered_14_of/ | {
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"Well it's a bit outside my area of expertise, but if I had to make such an estimate, I would look at the rate at which we're discovering new species, and how that rate has changed over time. That would allow me to estimate how many species we're likely to find in the future. If the number is much larger than the number of species we already know, that would get your 14%.",
"It's based on the difficulty of finding new species, if everywhere we looked we found a new species, then we must not have found very many. If we've looked for decades and nobody found any new species then it's likely because there aren't any more left to be found.\n\nObviously, we find new species at a fairly consistent rate, and there is a very large number known already. I'm sure someone has used these numbers to make a guess, I have no idea how accurate they are.",
"Not an exact answer but two that may help.\n\nMany of the worlds species are insects, and many of those are thought to be beetles.\n\nOne bit of information that supports this theory comes from an attempt to document the number of species within a, relatively, small forest encampment. The researchers found that with each tree that was shaken to gather the insects on them, that there were many unique beetle species. Almost a new species per tree.\n\nAditionally, and unrelated to beetles, is that fact that we havent explored our oceans all that much. And that means that we've yet to find all the species that inhabit the oceans.",
"A large chunk of it would come from barely explored / completely unexplored areas, i would be curious to see the source from which you got these 14/86 numbers and its age. \n\nBut back to the point, we barely understand the ocean and have trouble even fathoming the deep ocean. \n\nbased on the phrasing of organism this would include bacteria and other single cell organisms, which is where a vast majority of that percentage would be made up, as well as Extremophile {things that live in previously thought unlivable places, super cold/hot/acidic ect.}\n}\n\ni hope that helped, i'll try to get back to any replies \n \np.s. this is not my field of expertise just a thing i find interesting and have recently been refreshed on with a book and some youtube vids.",
"(Undergrad Marine Bio student here) From my understanding, organisms that we may see as a singular species because they look identical could be very genetically different, to the extent that what we thought one was one species 10/20 years ago could be 2 or 3 different examples. \nOfcourse there's going to be species we haven't discovered but I think atleast half of that number is down to misidentification or lack of technology to analyse DNA. \nThe term species has changed a lot over the century too, which doesn't help. \nHope this is alright; I can find some examples if you want. ",
"Statistics like this are created based on looking at what is identified within a group.\n\nPerhaps an easier example.\n\nLet's say people are inspecting defects in a product. Someone in charge intentionally adds 10 defects. Then they watch and see what comes through the line, what is discovered by the process. If people only find 3 of the defects, then they can estimate they're catching 30% of the defects overall, letting 70% of the defects go through. On the other hand, if all 10 defects are discovered, then they know they're catching all or nearly all of the defects. The percentage of things they know about should roughly match the percentage of things they don't know about.\n\nIt applies to other statistics as well, like crime stats. They can look at crimes they know happened but weren't reported through official channels, and look at crimes they know about and were reported. Looking at the difference shows about how many crimes go unreported. It is not exact, but if people are careful about how they create the stats they can be fairly accurate. \n\nFor counting species there are several ways it can be done. One way is like above, to have one group track the number of species in an area and another group figure out how many are new. Another method is a linear regression, figuring out an approximately how many species there should be based on estimates and comparing it to how many have actually been identified.\n\nAlso, most of the species that aren't discovered are small things. We're down to small numbers of new birds and mammals, often they are sub-species that get reclassified as a new species, or they're highly specialized species living in a remote and small geographic area. \n\nIt is mostly bugs, fungi, and other small organism that are being discovered in large numbers. These are things that are hard to spot and identify, many only identified because of genetic testing on tiny or microscopic organisms.\n",
"It wouldn't surprise me of 84% is bacteria, viruses, plants and minuscule animals and only 2% are \"normal\" animals.",
"At least in the microbial world, scientists have catalogued genes found in a random spoon of soil and found that only a minuscule percent of genes belonged to organisms they knew of, which led them to conclude that only 2% of microbes are classified based on percent of known and unknown genes, or something to that effect. \n\nEdit: ELI5: People have looked at DNA found in dirt and figured out we only have seen very small percent of it before and most of it is unknown. ",
"Assuming this includes microscopic organisms, such as bacteria, we may not even have methods available to detect some existing species. Some bacteria can't be differentiated from one another unless using genomic data or other molecular markers, and these methods weren't invented until recently. There could be millions of microorganism species left to discover.",
"So it's like in Pokémon where you only know the outline of the animal but have to actually see it to get the full picture/\"discover\" it.",
"Humans probably wrought their extinction. Just like half of the vertebrae we have annihilated in our timely progresión. ",
"Fun fact related to this:\n\n25% of all known organisims in the animal kingdom are beetles: come from the order, coleoptera.\n\nI learned that from visiting the insectarium, in Montreal.",
"You just make a grid, say 1 foot by 1 foot and you check and see how many species are known within that grid. ",
"All sounds good, next question do we Exist?",
"My knowledge of cryptids and inner earth beings as well as air beings suggest this number is accurate. ",
"An estimated 86% of species are undiscovered, but not 86% of organisms. Many many many of this 86% will either have teeny-tiny populations, or will be so similar to already-discovered species that only an expert could tell the difference. \n\nAnd don't forget boring stuff that's easy to overlook like all the different kinds of lichen and bacteria. \n\nI don’t want to be too much of a killjoy though, there's almost certainly a bunch of mad shit in the deep oceans we haven't discovered yet. When we develop the technology to properly explore them it's going to be a whole new age of discovery for biologists. ",
"Scientists look at the rate of new species discovery each year for the past however many years and fit it to what is called a Logistic Growth Curve. The simplest way to think about it is like this: every time someone encounters what they believe is a new species they do some work to verify if it's really new or not. If the rate at which this actually results in a new species discovery is 50% then we are at the 'inflection point' of the curve and we know we've identified about half of the species on the planet (with slight variance). This percentage is tracked every year for the scientific community as a whole and from millions of these data point we can predict both where we are on the curve right now and where the curve will eventually level off. We aren't anywhere near the inflection point yet so the rate keeps increasing every year. \n\nWhere we are right now tells use the percentage discovered and where it levels off is the scientific prediction for the total number of species on the planet. To the average person this might seem really uncertain but the statistical significance of a result with millions of data points would only be off by a tiny fraction of a percent 99.9...% of the time at which time scientists use the data to claim a high degree of certainty.",
"I think the number is a fraud. The number has been created by people looking for grants. The more research which can be paid for, the better, in their eyes.",
"First of all - I found this story shocking and disturbing when I first heard it and I certainly don't condone these actions....but they happened and were detailed in the video I saw.\n\nI remember a documentary in the 90s where a guy would take a large tarp of plastic or cloth and stretch it out underneath a large tree in the Amazon rain forest. They would then shoot some gas up into the air that would kill like 99% of all creatures it contacted....or maybe it was just insects, I can't remember but I think it only affected insects.\n\nAnyways, for the next several hours the jungle would \"rain down\" the carcasses of dead insects onto the tarp and these scientists would collect the insects and categorize them. \n\nThey said that every time they did this they would get something like 20,000 different insects but what was surprising to them was that ~~90%~~ (correction it's 80%) of what they found were \"new to science\" every time they did this experiment.\n\nIt didn't seem to matter where they went.....they repeated this many, many times and every time they did it, ~~90%~~ (correction it's 80%) of what they catalogued was new to science.\n\nIt literally blew the top off of the previously held estimates for the number of species on earth and at the end, the scientists had to conclude that they simply had no idea where it would end nor how many species of living things were on the earth anymore.\n\n**EDIT - Found The Vid but not the clip I was referring to. It's called \"Web of Life: Exploring Biodiversity\" and was produced by PBS back in the 90s.** \n[Here's a clip...but not the one I referenced](_URL_2_)\n\n\n**EDIT 2 - [The original clip I was talking about](_URL_1_)** \nThanks to /u/QuietLuck for finding this (_URL_0_)",
"Well the way you calculate it is with a bit of estimation.\n\nSay that we have a box with a hole, and the box has 1000 colored balls inside you can take out through the hole. What we don't know is which colors, or how many colors the balls are.\n\nSo we take out one ball, and it happens to be blue! So now we know there's blue balls in the box. Great!\n\nNow imagine that there's only blue balls coming out. You pull out 10 balls and they are all blue, you keep pulling out 100 balls and they are all blue. Now we've only seen 10% of all balls inside the box, but we can start guessing that the chance that we never got another color means that most, if not all, balls are blue. Maybe we got lucky and only found the 100 blue balls first, but the chance of that happening are really small, theres 5958926632240478155489389057946132722598279588777288866613428027720091866834339557556406953783393337191792337384343797137527180562707601151082428455887739138152983603695993602780124665235348032787297990137398327480690965409929969664334240631387010833309096272433060469800960000000000000000000000000 different permutations (that is groups of balls we would pull out in an order) of balls we could have had, but only 1 of them would be if all of the balls were blue.\n\nNow lets imagine what would happen if instead the second ball we pulled out was a red ball. This time we know there's more than just blue balls in the box. Now imagine that every time we pull a ball it comes out a different color, and after pulling out 100 they are all a different color each. Now there's a chance that there's 100 colors and nothing else, and we just happened to pull out one ball of each color with no repeats. The chance of this is a little bit higher than taking out all the balls of one color, but it still is very very very small. You'd have to be very lucky, it's a better guess to think there's still many colors we've yet to find. Maybe not 1000, but certainly more than 100.\n\nSo we can use the history of how many new colors we discovered as we saw each ball and create a good guess of how many colors probably exist in the box, and how many we know already.\n\nThe same thing can be done with organisms. We know more or less how many insects, fungi, plants, animals, bacteria etc. exist on earth by knowing how many resources they need, how much spaces is available, doing thermodynamic studies, etc. From there we notice that as we look at animals and see what species they are, we find new species every so much. Just like with the colors, we can guess how many species we probably haven't seen yet.",
"The vast majority of distinct living organisms on earth are single-celled bacteria and archaea. Greater than 90% of these cannot be cultured in laboratory conditions to enable their study and classification. Consequently, the majority of currently extant, distinct species on Earth have not been described.",
"Progress towards any achievement such as this can usually be found through the main menu, reached by pressing the 'start' button.",
"Scientists have estimated ranges for the number of organisms that have yet to be discovered. All of the methods involve extrapolation from known data. For example, some scientists have used size estimates. The bigger the creature, the more likely it is that we have found it. The opposite is true for smaller organisms. So scientists make estimates that there are x number of small creatures yet to find. Another example is to use discovery rates and types of organisms. We are discovering fewer and fewer new mammals but are still discovering new fungi or bugs. So therefore the amount of bugs yet to find is greater than mammals. Another way is to use symbiotic or close relationships. If we know that there are x types of trees in the forest and know that each type of tree is likely to be home to x number of unique bugs then we can estimate how many unknown trees may have x unknown bugs. ",
"It would help if you were to point us at where someone said that we have discovered 14%.\n\nAnyway, here's an example: you want to know how many tigers there are in a forest. You can't measure that directly, but you can do the following:\n\n* Capture some tigers (say 100) and tag them.\n* Come back later and capture more tigers (100 of them). See how many that you caught this time have tags (say 10).\n\nYou can use that to calculate how many tigers there are. The best estimate is that 10% (10/100) tigers have tags on them. If you have tagged 100 tigers and that is 10% of the tigers, then there are 1000 tigers in the forest. This is all approximate, and you can do statistics to determine the probability distribution of tiger numbers.\n\nYou would also tag the second set of tigers, so a total of 190 tigers would then have tags. The third time, you would expect that of your 100 tigers you catch that about 19 (190/1000) would have tags on them. \n\nYou can do the same thing with anything that you are sampling. Find an organism, see if we have found it before, and repeat. That will tell you how many of the things that you find are new and how many we have already discovered. \n\n",
"I do this! Woohoo!\n\nEducated guesses are how science works. When enough educated guesses are unable to be disproved, there's a consensus. In this case, a bunch of people came up with different statistical methods to estimate diversity (fancy examples include Chao1, Simpson diversity index and rarefaction). A pretty good estimate can be made when enough scientists approach it enough ways.\n\nMore advanced: Take a given sample or dataset (e.g. soil sale or ocean) and perform relatively standardized genetic similarity analysis to estimate species (known and unknown categories). Then do bootstrapped subsampling of species diversity per fraction of the sample (e.g.\n10 unique species at 0.1 of the total sample, 50 unique species at 0.2... Repeat a lot). Fit a regression (usually nonlinear) and estimate the total unique species, including those you never observed, in that sample with CIs. Do this for a bunch of different types of samples, build a final model and you get a good idea of what we're missing!",
"From a recent paper:\n\n > Global species richness, whether **estimated by taxon, habitat,\nor ecosystem**, is a key biodiversity metric. Yet, despite the\nglobal importance of biodiversity and increasing threats to\nit (e.g., [1–4]), we are no better able to estimate global species\nrichness now than we were six decades ago [5]. **Estimates of\nglobal species richness remain highly uncertain and are often\nlogically inconsistent** [5]. They are also difficult to validate\nbecause estimation of global species richness requires\nextrapolation beyond the number of species known [6–13].\nGiven that somewhere between 3% and > 96% of species on\nEarth may remain undiscovered [4], depending on the\nmethods used and the taxa considered, such extrapolations,\nespecially from small percentages of known species, are\nlikely to be highly uncertain [13, 14]. **An alternative approach\nis to estimate all species, the known and unknown, directly.\nUsing expert taxonomic knowledge of the species already\ndescribed and named, those already discovered but not yet\ndescribed and named, and those still awaiting discovery,** we\nestimate there to be 830,000 (95% credible limits: 550,000–\n1,330,000) multi-cellular species on coral reefs worldwide,\nexcluding fungi. Uncertainty surrounding this estimate and\nits components were often strongly skewed toward larger\nvalues, indicating that many more species on coral reefs is\nmore plausible than many fewer. The uncertainties revealed\nhere should guide future research toward achieving convergence\nin global species richness estimates for coral reefs\nand other ecosystems via adaptive learning protocols\nwhereby such estimates can be tested and improved, and\ntheir uncertainties reduced, as new knowledge is acquired\n\n > Current Biology\nVolume 25, Issue 4, 16 February 2015, Pages 500-505\nSpecies Richness on Coral Reefs and the Pursuit of Convergent Global Estimates\n_URL_0_",
"There's a lot of information that goes into this. For example, Charles Darwin once predicted the existence of a type of moth with an unusually long proboscis. He based this prediction on the existence of a flower, varieties of which were pollinated by moths elsewhere. This particular flower held its important bits at the bottom of a long, narrow shaft. \n \nDarwin was right; the moth was discovered years later. It could have been something else, but the point here is that *something* had to be pollinating that flower, and it was nothing that was known at the time he made his observations. \n \nSpecific niches, like the above, are one factor. Mathematical studies are another; \"in this kind of environment elsewhere, with similar temperatures and other conditions, we see 'X' in terms of diversity.\" It's never guaranteed: most of these factors are educated guesses, but when estimates are published they actually lean towards the conservative end of the range -- just to be safe. \n \nThis is why popular news often presents new discoveries as \"surprising scientists\" and \"upsetting estimates\" in terms of their diversity, range, etc. Science has to fight tooth and nail for recognition and funding as it is -- so, when scientists think there might be 4-12 of ABC, they'll say \"we're expecting to find 4 ABC; even 3 would be remarkable, really.\" \n \nThey wind up finding 6-8 ABC, whereupon the public shakes its head and goes \"Silly scientists don't know what they're talking about, but let's support more research, since there's obviously a lot more ABC out there than they thought.\"",
"Imagine you sample every organism in a 1m patch of grass, and find 25 species. Next, count all the species in a 5m patch, and you get 60 species, but 20 are the same as before (so 40 are new). Keep doing this over multiple habitats and habitat size, and you build a curve that describes how many new species you expect to find in a new area of size x. This is called rarefaction, and extrapolating over the area of earth gives a rough approximation of how many species we expect to find. \n\nMany ecologists have studied this statistical phenomenon. Search species - area curve, biogeography, or MacArthur to learn more. ",
"I think it's kinda like how we haven't discovered all the different types of sandwiches yet. Every time I go to the deli there's a couple new ones on the menu.\n\nYou're welcome.",
"I assume by \"organisms\" they mean \"species\".\n\nBut, what does it even mean to be a species? \n\nAn article in Science just demonstrated that all the Major Big Cats (lions, leopards, etc) have been interbreeding for millions of years.\n\nThey all have pretty much the same genes, just shuffled around.\n\nSo, every time you find a different combination or permutation, is it reasonable to call it a different \"organism\"?\n\nThe accident of infertility between certain combinations can hardly be taken anymore as the definition of a species.\n\nLife begins to look more like a multi-dimensional continuum, with some neighborhoods being more densely populated than others. \n",
"85% of statistics are made up on the spot. I know because my dad was a statistics professor at UGA. ",
"There are various methods of population estimation.\n\nA common method is as follows: \n* You spend a set interval catching the critters of interest. \n* You tag all of the critters you catch and release them. \n* A short while later, you do this again. \n* Some of the critters in the second round are _already tagged_.\n\nThe total catch per interval and the fraction of repeat catches can be plugged into some relatively straightforward statistical functions to estimate the total population.\n\nYou can do this for as many iterations as you like to get an arbitrarily accurate estimate. \n\nAnother method is to designate a certain amount of space and count _everything_. It might be all the fish in a cove, all the plants in a 2mx2m patch of field, all the bugs in a tree, etc. You do this a couple times, and then multiply your critters/unit number by the total number of units.\n\nThe figure you're quoting can be arrived at by a combination of the two. If you catalogued _everything_ in some space, and you'll consistently get about 14% previously-identified species and the other 86% would be new (and probably mostly beetles).",
"So there's hope for samquantch?",
"Earth scientists and biologists: What do they know, do they know things? Let's find out!",
"I have heard that most organisms are actually in the ocean, since the earth is mostly water, and we don't have the ability to explore the ocean that far beyond the surface. "
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"https://www.youtube.com/watch?v=LdPDWGqjWh4&app=desktop",
"https://www.youtube.com/watch?v=bnsl5OpjwEY"
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1p73hf | How do I calculate laser divergence? | I was reading [the wiki page on beam divergence](_URL_0_) and here's what (I think)I understand:
First I need to find the divergence angle(theta?) using the equation:
(laser wave length) / (pi * initial beam width)
So a 500nm laser with initial beam with of 1cm(10,000,000nm) would be:
500 / (pi * 10,000,000) = 0.000157
Here's where I am lost. What unit is this number in and how do I calculate the actual divergence(let say this beam at 1km distance)?
| askscience | http://www.reddit.com/r/askscience/comments/1p73hf/how_do_i_calculate_laser_divergence/ | {
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"The units of the result are [radians](_URL_0_). \n\nThis is a unit that is actually dimensionless. That is, an angle of one radian is an angle that forms a circular arc with a length equal to its radius. Meaning, radians measure the ratio between two lengths, thus it is not actually a unit at all.\n\nRadians are used in most scientific and engineering contexts in college coursework and onward because they actually simplify many of the calculations we do, compared to using degrees to describe angles."
]
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"http://en.wikipedia.org/wiki/Radian"
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ar9n23 | how do showers pump water to the highest floor? | So a "pushing" is applied to water in a pool somewhere underground. But what is doing that pushing?
& #x200B;
Is it air pushing onto the surface of the liquid? How do they fit the extra air in without some leaking back out?
Is the liquid essentially being compressed and its volume maintained by being forced up a narrower pipe? (this sounds very unwieldy)
How is a force even transmitted everywhere in a liquid? The molecules at the top experience an electrostatic repulsion which probably induces more repulsions in the next layer. But when this downward pushing reaches the bottom of the tank, presumably the third law pair between the bottom layer of water and the tank results in no overall upward motion (and no downward motion because the tank is fixed to the Earth)? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ar9n23/eli5_how_do_showers_pump_water_to_the_highest/ | {
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"I would say that it mostly depends on your location. A lot of places such as New York City have water towers placed on top of the buildings that feed via gravity.\nA lot of small towns where you see large water towers up high above the town essentially do the same thing.\nThen there will of course be situations where gravity cannot be used and that's pressurized system will be put in place.",
"Pumps mostly. The pump puts pressure on the water in the system. They also push water up into water towers so that when there is a lot of demand on the system, gravity on the water in the tower can help keep the pressure high enough.\n\nThe liquid doesn't need to be compressed to be under pressure. You can have a cinder block and put a heavy weight on top and the cinder block remains the same shape, but there's still pressure on it.\n\n > How is a force even transmitted everywhere in a liquid?\n\nWhen you put the liquid in an enclosed space like a pipe and you start applying pressure, it can't compress the water because of that electrostatic force that you mentioned. So that pressure has to go somewhere. One section of the pipe pushes on the next, which pushes on the next, and so on. It's just like a train pushing cars.\n\nIn something very tall, the building will have additional pumps inside the building to help maintain pressure up on the higher floors. They will often also have their own water towers on the roof to help keep the pressure even at all times.\n\n\n[Here's a neat video about water pumping and water towers.](_URL_0_)"
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ue5bx | Do Large Lakes Serves as Natural Storm Breaks? | I live about 20 miles due east of a relatively large lake/reservoir near the outside of where most Midwest thunderstorms develop. When I view them on public radars I've noticed a trend where large or severe storms will tend to split or break up as they approach this lake.
I know that the air conditions around large bodies of water are significantly different because of the heat exchange, but is that the primary reason for this phenomenon I've observed? For that matter, is there any real science to this at all? | askscience | http://www.reddit.com/r/askscience/comments/ue5bx/do_large_lakes_serves_as_natural_storm_breaks/ | {
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"Yes, you're correct. **Lake modified air** can have an impact on these types of storms. Mostly in a way directly [opposite to this](_URL_2_) in the winter. In the spring/summer the lake is relatively cool compared to the land and induces subsidence (sinking air) that can inhibit thunderstorms which need [heat and rising air](_URL_0_) to survive. The larger the lake (e.g. Great Lakes) the more of an impact it will have for longer into the spring/summer.\n\n\nAnother impact can be topography that sometimes surround lakes. From [this diagram](_URL_1_) you can see that the moist air is forced up over the terrain and the water precipitates out, leaving little moisture on the lee side of the mountains or hills."
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"http://www.windows2universe.org/earth/Atmosphere/tstorm/tstorm_formation.html",
"http://upload.wikimedia.org/wikipedia/commons/9/9a/Rainshadow_copy.jpg",
"http://www.erh.noaa.gov/er/buf/lakeffect/form.html"
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2l1j5i | During the Carboniferous, O2 levels were 163% modern levels while CO2 was 800ppm. With so many plants, why were CO2 levels so high relative to modern levels? | If anyone can provide a detailed figure for the varying levels of O2 and CO2 that would be fantastic (because obviously these values fluctuated). Curious to know why the CO2 was so high relative to modern levels though - was it due to stomata size / density? With such high CO2 was ocean acidification far more prominent thus preventing the formation of limestone (or greatly reducing the sink)? Or was it both or something else entirely? | askscience | http://www.reddit.com/r/askscience/comments/2l1j5i/during_the_carboniferous_o2_levels_were_163/ | {
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"Are you sure you mean the Carboniferous here? That period actually saw a huge drop in global CO2 level, indicated by \"C\" [in this graph](_URL_0_) around 300-350 million years ago. \n\nThose pCO2 levels had been steadily falling since the Cambrian period, but likely saw an extra large drop during the drop as the climate transitioned from greenhouse to icehouse and massive glaciations occured...and as temperatures fall, ocean CO2 solubility increases.",
"If you think of the Carboniferous period as the time that coal deposits formed as plant matter couldn't decay as efficiently then as today (fungi and bacteria hadn't yet evolved the ability to digest cellulose), it makes sense. There is a set amount of carbon near the surface of the earth. It can either be in the air as CO2 or locked up in plant matter or buried a bit under ground. The Carboniferous period was a transition time during which atmospheric carbon was moved underground. Today we are digging up those deposits and putting them back in the air, potentially returning closer to those at the beginning of the Carboniferous."
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"http://upload.wikimedia.org/wikipedia/commons/7/76/Phanerozoic_Carbon_Dioxide.png"
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27jxv7 | What are the neurological differences, if any, between reading a physical book and reading online? | askscience | http://www.reddit.com/r/askscience/comments/27jxv7/what_are_the_neurological_differences_if_any/ | {
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"I'm not entirely sure about the standards of this journal, but it does have citations. I'll try to sum up the author's major points that are at least supported by studies:\n\n1) Reading online requires much more \"cognitive space\" for a number of different reasons. The use of hyperlinks embedded within texts leads to more decision-making to be made, which of course requires more use of the brain. Just like when reading a paper newspaper, when one is confronted with many different choices in terms of what to read, one needs to make more cognitive decisions in selecting the most appealing thing to read. Also, websites that require scrolling to read the full text leads to greater brain activation that websites that do not require scrolling.\n\n2) The framework of the text (paratext) has an influence on the reader's response to the text. In a normal book, we have the acknowledgements page, title page, etc. that all shape our view that \"we are reading a book\". Similarly, a study showed that subjects were more likely to perceive humor in a text when reading on a lighter, clearer device.\n\n3) Online multitasking while reading on a screen most likely leads to a reduction in comprehension of and \"deeper\" thinking about the text. However, a link between reading comprehension and reading on paper vs screen is still not definitive, because studies have found conflicting results.\n\nThis is clearly still an emerging field of study, as e-readers and e-books have only become popular in recent years. I'll be curious to see what the results are from more careful scientific studies.\n\n_URL_0_\nBarry W Cull, \"Reading Revolutions: Online digital text and implications for reading in academe\""
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"http://firstmonday.org/ojs/index.php/fm/article/view/3340/2985#p10"
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a8avzp | Does Mars have enough mass to support a habitable atmosphere? | askscience | https://www.reddit.com/r/askscience/comments/a8avzp/does_mars_have_enough_mass_to_support_a_habitable/ | {
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"Titan, a moon of Saturn, has about 1/5 the mass of Mars but holds an atmosphere with 1.5 times Earth's atmospheric pressure. So theoretically yes.\n\nOne big difference is that Titan is much colder than Mars and nowhere near habitable, but it turns out even with Mars's higher temp, it should be able to hold onto a significant atmosphere over billions of years. So why hasn't it?\n\nHere I quote from [Principles of Planetary Climate](_URL_0_) Chapter 8\n\n > It takes rather little impactor mass in the late stage veneer to deplete the atmosphere of an Earthlike planet – only a tenth of a percent of Earth’s mass, which is not an unreasonable amount to be left over after the assembly of an Earth-sized planet. An important result is that if Mars were to start out with a 2 bar CO2 atmosphere (as suggested by some climate calculations based on evidence for warm, wet early conditions), its atmosphere would not be much more subject to erosion than Earth’s. The mass of available impactors required to erode such a Martian atmosphere would be fully 70% of the corresponding mass for Earth. The main reason the estimates are so similar is that a 2 bar atmosphere on Mars has much more mass per unit area than Earth’s atmosphere, requiring a higher critical mass of impactor as compared with Earth. A more tenuous Martian atmosphere is much more erodable than Earth’s, as illustrated by the 100 mb Mars case in the table. Similarly, if Venus had an Earthlike atmosphere, its atmosphere would be essentially as erodable as Earth’s, whereas the actual dense Venus atmosphere requires about seven times as much available impactor mass to erode. The hypothetical Super-Earth case is only a bit less subject to erosion than Earth, in this case because a 1 bar atmosphere on a large planet has less mass per unit area than Earth’s atmosphere. The importance of the atmospheric mass effect shows also in the hypothetical planetary Titan case, which, owing to its very massive atmosphere, requires nearly as much available impactor mass to erode as does the 2 bar Early Mars case. The real Titan, in contrast, is very difficult to erode, requiring an available impactor mass of nearly a tenth of Earth’s mass, owing to the competition with Saturn for impacts.\n\n > The essential puzzle posed by the results of Table 8.7 is that it looks quite plausible that Earth’s atmosphere would be subject to loss by impact erosion in the Sweep stage, and that a dense Early Mars atmosphere would not be appreciably less erodable than Earth. How, then, to account for the present tenuous Martian atmosphere, while Earth has a substantial atmosphere remaining? One potential scenario is that Earth’s atmosphere was indeed lost by impact erosion, but was regenerated by outgassing from the interior. Consistent with this picture, we note that while Mars requires nearly as much available impactor mass as Earth, this impactor mass is delivered over a much longer time, owing to the smaller cross- section of Mars. Combined with the relatively early shutdown of tectonic activity and hence outgassing on Mars (owing to its small size) it could be that the essential difference between the planets resides not so much in ability to hold an atmosphere as in ability to regenerate an atmosphere. A severe difficulty with this picture, however, is the abundance of N2 in Earth’s atmosphere. A CO2 or water vapor atmosphere could be easily regenerated, but it is not easy to hide enough N2 in the mantle to allow this component to be regenerated. And recall that Venus has even more N2 in its atmosphere than Earth, suggesting that even if Venus went through an early stage with far less CO2 in its atmosphere, it did not suffer total atmosphere loss by impacts during that stage. Could it be that there is an ability to sequester a bar or two of N2 in a planet’s mantle? Could it be that Earth started out with much more N2 in its atmosphere and that what we have today is the small bit left over after substantial impact erosion? Or could it be that the mass of impactors was not in fact sufficient to deplete Earth’s atmosphere and that the tenuous Martian atmosphere has some other explanation? Perhaps it never generated a dense atmosphere, because it never received enough oxygen-bearing material to turn carbon into carbonate and CO2. Perhaps Mars lost its atmosphere in a chance giant impact which got rid of Martian N2, whereas Earth’s Moon-forming impact was not big enough to get rid of all the N2. If a giant impact removed most of the primordial N2 on Mars, then perhaps the rest could have been lost by non-thermal escape and solar wind erosion. But if Mars lost its atmosphere too early then it becomes hard to account for the large, extensive water-carved channels on Mars, some of which suggest persistence of active surface hydrology up to 3.5 billion years ago, with episodic recurrence of less extensive river networks extending billions of years later. More precise dating of these hydrological features, which will come ultimately with sample return missions from Mars, will go far to help resolve these puzzles. Still, the Mystery of the Missing Martian Atmosphere is likely to remain one of the Big Questions for a long while to come.\n\n > How do giant impacts fit into the picture? Giant impacts do not come in a continuous stream, but lunar to Mars-sized bodies are common enough in the late stages of planetary formation that it is likely that one or more giant impact occurs before the planet attains its final size. The very existence of the Moon provides evidence that Earth experienced a giant impact, while the anomalous retrograde rotation of Venus has been taken as evidence that a giant impact occurred there as well. The Martian crust exhibits a striking dichotomy between rugged thick-crusted and heavily cratered southern hemisphere highlands and smoother, thinner northern hemisphere lowlands; this has sometimes been taken as having resulted from a giant impact, though one smaller in relative scale than Earth’s Moon-forming impact. A single giant impact can blow off an entire atmosphere, but this is not inevitable; depending on the energy of the impactor, there can be a substantial proportion of the original atmosphere left. The issues in reconciling the histories of Earth and Mars are essentially the same as for impact erosion at the Sweep stage: how do we account for the story of N2 on Earth (or Venus, for that matter)? And how are we to account for the hydrology of Early Mars if a giant impact blew off the primordial Martian atmosphere but the planet was unable to regenerate a new CO2 atmosphere by outgassing?"
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177lwi | the american game-show 'jeopardy' | As a Brit I have never been exposed to the game-show apart from the odd bit through pop culture. Would anyone mind explaining it to my simple British mind? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/177lwi/elif_the_american_gameshow_jeopardy/ | {
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"just a trivia show. There are three rounds. First and Second rounds have 7 (I think) categories with 5 questions each. Wrong answers deduct dollars.\n\nLast round is a single question. Players are given the category ahead of time and can wager whatever amount of money they have on whether they'll get the question right.\n\nMost money at the end wins.",
"Not much to explain. It's a trivia show quiz show where answers must be given in the form of a question.\n\n_URL_0_",
"Standard quiz/trivia show. The players' scores are in \"jeopardy\" throughout because wrong answers subtract from their total. Another gimmick is that the clues are provided in the form of a statement and the participants have to respond in the form of a question.\n\n3 rounds: Jeopardy, Double Jeopardy, and Final Jeopardy\n\nJeopardy has 6 categories of 5 questions each (ranging from $200 to $1000). \n\nExample: \nPlayer - I'll take Websites for $400, Alex. \nAlex Trebek - It's a place where user-submitted links are voted up or down by the rest of the users. \nPlayer - *rings in* What is reddit?\n\nFailing to phrase your response as a question counts as incorrect, but you have a few seconds to correct your mistake if you forgot.\n\nDouble Jeopardy is the same, but the values are doubled (ranging from $400 to $2000 per question/answer).\n\nThe first two rounds have Daily Doubles as well (one in the first round, two in the second). When selecting a clue, the player gets a special clue just for them (the other players can't ring in), and they get to wager how much they want to earn/lose on the result. So making something a \"true Daily Double\" means betting your entire score.\n\nFinal Jeopardy is like a Daily Double for all players. The category is given, players get to decide how much they want to bet on a single question, then they hear the clue and have 30 seconds to write down their response.\n\n*edit* Daily Doubles are hidden, so there's no way to know which clue is going to be one. They tend to be in the lower half (i.e. higher-scoring clues) of the board.",
"Contestants are given the opportunity to answer questions with associated monetary values. A correct answer credits the contestant with the associated value; an incorrect answer debits the contestant in the same amount. So there's a penalty to just guessin'.\n\nThe questions are well known for being challenging, but the range is quite broad. Some questions have obvious answers anyone could guess; others have obvious answers but are worded in such a way as to make them tricky to guess. Still others are questions you either know the answer to or you don't. Who was Henry VIII buried next to? Either you know that or you don't. (It was Jane Seymour.)\n\nThe gimmick of the game is that the \"questions\" are phrased as if they were answers, and the contestants are required to provide the questions to which those are answers. In the above example, the \"question\" might have been \"She's the wife of Henry VIII next to whom he was buried,\" and an \"answer\" might be, \"Who was Jane Seymour?\"\n\nThis is a formality more than anything. Many consider the game to be *slightly* more challenging because the \"questions\" must first be parsed to figure out what the correct response needs to be. First you must unpack the \"question,\" then you have to come up with the correct answer to the question, then you must phrase the correct answer in a way that's acceptable to the judges. This makes the whole game a *bit* tricker and more interesting than just answering questions. How much tricker, and how much more interesting, is of course in the eye of the beholder.",
"It's essentially a trivia game. \n\nYou pick a category and a dollar value and then you get a clue in the form of an \"answer,\" for which you have to provide the question. So, you might get an \"answer\" like \"This president was elected in 2008.\" The correct response would be \"Who is Barack Obama?\"\n\nThere are three rounds. In the first, the clues are valued at between $200 and $1000, and there is one \"Daily Double,\" a clue for which you can bet all, part, or none of your current winnings. In the second round the clues are worth $400 - $2000 and there are two daily doubles. The third round is \"Final Jeopardy,\" in which the players are given the name of a category. Then they must bet all, part, or none of their winnings before seeing the question. The winner's the person with the most money at the end of Final Jeopardy. ",
"Answer questions, get money. ",
"To add a few more details to the other excellent descriptions:\n\nThe winner from the show gets to come back the next night and play against two new contestants. This continues until the person is defeated.\n\nThe interesting thing about Jeopardy is that it's a show where you have to have pretty good breadth of knowledge to do well, and contestants appear to be pretty smart individuals. On many other game shows in the U.S., contestants seem to be more like \"regular people\" and aren't necessarily that exceptional. Yet the prizes for Jeopardy aren't that lavish--you can be a jeopardy winner and take home less than $10,000, depending on how the game goes. Taken together it means that being a contestant on Jeopardy, or even just playing along at home, has more status & intellectual cachet than competing on/watching other shows.",
"Probably the most confuddling thing about it is the way questions are posed and asked. Jeopardy! was created at a time when there was a big scandal about game shows being rigged, where contestants were \"given the answers\". \n\nSo when Jeopardy was created, the joke was that the contestants *were* given the answers, openly. The task for them was to provide the questions. So that's why the questions are always nonsense like like \"what is Damascus?\""
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6zlgr0 | what is the premise of the 'shadow' that carl jung wrote about? | I've tried reading about it but it keeps going over my head, it won't stay in! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6zlgr0/eli5_what_is_the_premise_of_the_shadow_that_carl/ | {
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"The idea is that we look at ourselves in a good light, and this casts a shadow that hides from us our true selves.\n\nHe believed that we had to face that shadow in our journey to self realization. Facing that shadow means recognizing that all the worst parts of humanity are in you too. If you were born in Nazi Germany to a German family, there is a good chance you would have been a Nazi. You wouldn't have had some moral epiphany and rallied against your people, you would likely have taken part in the Holocaust.\n\nFor a better look at that idea. What it takes for a normal person, you or me, to turn into that kind of a monster, read Ordinary Men. "
]
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40le3p | how can the suns rays make you feel mentally/psychologically better? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/40le3p/eli5_how_can_the_suns_rays_make_you_feel/ | {
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"Mostly your brain (pineal gland) produces two kinds of \"drugs\" (hormones): one for the day (serotonin) and one for the night (melatonin). This is part of your inner clock. Serotonin keeps you awake and melatonin makes you sleepy. Light, specially sunlight, stops the production of melatonin. So if you would stay in dark places without (sun)light over a long period of time, the levels of melatonin would be very high and you would be, more or less, feeling sleepy all the time. When the balance of serotonin and melatonin in your body is messed up, your inner clock is also messed up. This leads to e.g. sleep disorders, depressions and some other stuff that isn't very healthy either. \n"
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fq5jqz | how can people take old videos and upscale them to 4k? | The video that made me ask this is this one [_URL_0_](_URL_0_)
A-ha: Take on me in 4k. How is this possible when 4k didn't exist when the video was made? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fq5jqz/eli5_how_can_people_take_old_videos_and_upscale/ | {
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"That video was recorded in 1985 on film from my understanding.\n\nFilm itself has a resolution way beyond 4K depending on the grain size. As long as the film is preserved, it can be re-scanned using a higher resolution scanner.\n\nWe will probably get an 8K cut in a few years.",
"The video would have been recorded onto film given its era. Photographic film has really high resolution we just don't associate high resolution with the old analog TV era because the TVs didn't have much to work with, but movie film is somewhere in the 4k-16k range depending on the size and quality of film. If they had a good quality recording then its just a matter of scanning it in really nicely and you have a 4k music video.\n\nThis is why old movies can also be upscaled to 4k(but they often have film grain and anomalies from years in storage) but more recent movies that were shot and edited digitally cannot be. If the movie was captured on an early digital camera at 2k resolution (roughly 1920x1080 or 1080P) then you don't have the raw data to work with. You can fudge it in post processing(which your TV will do) but its not quite the same"
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byeeg1 | why does water and air feel different at the same temp? full question below. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/byeeg1/eli5_why_does_water_and_air_feel_different_at_the/ | {
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"text": [
"Transmission of energy. Water holds and absorbs tremendously more energy than air, that's why it takes so much more airflow volume to create the same cooling effect as water."
]
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bndjtz | The Great Arab Revolt | I've been reading about the period of 1915 - 1918 which is when the Great Arab Revolt happened.
& #x200B;
My question is: Arabs revolted against the Ottoman Empire alongside the British and French while at the same time, Arabs fought (Might have been forceful) with the Ottomans against the Colonial forces. How did this split happen in the Arab world where some fought with the Ottomans and some fought against?
& #x200B;
Thank you | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/bndjtz/the_great_arab_revolt/ | {
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"I'll try to answer your question, sorry if it doesn't satisfy you.\n\nFirst, despite its name (and what was believed to be by Arab and Turkish nationalist historiography), there was no general \"Arab Revolt\" against the Ottoman Empire. Firstly, Husayn, the leader of the revolt, was not an Arab nationalist, and he did not adopt the ideology of Arabism. He was an ambitious dynast who used his Islamic status as a *sharif* and the *amir* of Mecca in an attempt to acquire a hereditary kingdom or principality for his family. He even stated that his objective was to free the caliph from the \"atheistic\" clutches of the CUP regime rather than overthrowing him. Second, Although clandestine support for the revolt existed in some parts of Syria, Husayn’s call failed to generate any organized or widespread response in the Arabic-speaking provinces. Many Arab public figures even accused Husayn of being a traitor and condemned his actions as dividing the Ottoman-Islamic Empire at a time when unity was crucial. Rather than a popular uprising against the Ottoman Empire, the Arab Revolt was a more narrowly based enterprise relying on tribal levies from Arabia and dominated by the Hashemite family. Huge subversion among Arabs in the Ottoman army as had been expected by the British Arab Bureau never materialized, even after Sharif Hussein’s revolt in 1916. No Arab units of the Ottoman army came over to Hussein, and from British intelligence memorandum, many Arab soldiers continued to demonstrate loyalty not only to Islam but also to the Ottoman government. Except for a few thousand tribesmen, most Arabs remained loyal to the empire during the traumatic events of the times\n\nIn my knowledge, the Arab mobilization during the First World War was less researched, and the fragmentary evidence we have doesn't help. However, using a general calculation, the Ottoman armed forces would have comprised by 47% Turks and Anatolian Muslims, 37% Arabs, 8% Ottoman Greeks, 7% Armenians and 1% Jews. The motivation for the Arabs to join the Ottoman army varied.\n\nSome enthusiastically joined, motivated with nationalist fervour or *jihad* propaganda. In Damascus, the population was opposed to Great Britain, Russia and France while the Muslim population of Palestine held anti-British feelings as well. With the onset of the war, propaganda and rumours filled the town that the army intended to invade Egypt and free it from the British rule. The propaganda succeeded in winning the wholehearted support of the Arab Muslims and soldiers, a few weeks before the expedition the enthusiasm and excitement of the people reached a ‘fever pitch’ in Jaffa. Parades and celebrations of all kinds in anticipation of the triumphal March into Egypt were taking place and the enmity against the Entente states was at the centre of the propaganda. Even Arabs that made bitter remarks against Germany for not helping the Ottomans during the war against Italy soon underwent a change and they came to realize that the Ottomans had taken up arms against Russia and that Russia was considered first and foremost the arch-enemy. Reports on German victories also had a powerful effect on them. Similar propaganda was directed at the soldiers who would invade Egypt since many of the Arab soldiers were not acquainted with the disciplined character of military life. To increase their enthusiasm, Cemal Pasha, the theater commander used both jihad propaganda and the argument that the Egyptians were ready to revolt against British rule. He had many Arab scholars preach to the Arab soldiers before and during the first attack against Egypt. These military employees strolled through the camps and delivered vehement speeches. Their orations were so influential among the common Arab soldiers that some had fits of hysteria due to the excited preaching.\n\nOn the other hand, some were also forcefully mobilized with no other choice. These forced conscripts had almost no option but to join the army. The alternative was often death by starvation. Moreover, the conscripts, isolated in their camp life, developed a critical distance from the normative ethics of their original communities when they moved to the margins of major cities like Alexandria and Cairo. Families also mourned the loss of their sons, who were the backbone of the family. They dodged conscription with hiding in villages, prepared hiding places in the houses, fields, caves, with Bedouin families or in other out-of-the way places. When apprehended, suspected draft evaders were usually convicted by military court and often sentenced to flogging. Many also mutilated themselves to avoid draft, but since the ultimate consequence of capture was often military service, applying effective deterrent measures was nearly impossible. Many also avoided draft by moving to Mecca and Medina, as the the cities were exempted from mobilization. Evidently, the number of young pilgrims to Mecca spiked during recruitment. For the less pious, two popular options for circumventing military service remained substitution (sending a personal replacement) and payment of forty to fifty liras, which get increasingly higher as the war progressed. For the non-Muslims, changing nationalities, fleeing abroad, or paying the individual exemption fee was the common course to avoid draft\n\n**Sources:**\n\n*A History of the Modern Middle East 6th Edition* by William Cleveland and Martin Burton\n\n*The Ottoman Mobilization of Manpower in the First World War* by Mehmet Beşikçi\n\n*A Land of Aching Hearts* by Leila Tarawi Faraz"
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4tfbu3 | A poor family living in the woods circa 1500; how did they find husbands and wives for their children? | I recently saw the movie "The Witch" (terrible), but it made me wonder where they would find spouses for their children. The village shunned them, and there's no one else around.
Edit: Specifically England and settlers of New England. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4tfbu3/a_poor_family_living_in_the_woods_circa_1500_how/ | {
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"Hi, can you specify which region/culture you're asking about? That will greatly assist anyone contemplating answering here. Thanks! ",
"The average woods-living family would not have been quite as isolated as the family in that movie. Remember that they were explicitly ostracized and thus unable to associate with society. But the average family would have had plenty of opportunities to meet new people. \n\nWhile you did specify time and place, the answer is going to be much the same for any traditional, rural, Christian community. For the record, my specialty is in Italian society of the same period. \n\nFirst, obviously, is church. Every Sunday, at least, they would have made the trip to the nearest one. There they would have gotten to know the other children who lived nearby and probably had their first flirtations.\n\nThen there are dozens of holidays and festivals, both Christian and secular (i.e. Harvest, May Day), that would have brought families from the countryside down to the village centers. As opposed to church, these visits would have given young people the chance to run around and socialize with their peers with minimal adult supervision. \n\nFinally, depending on your father's profession, you might accompany him to town on market days or business trips. This way you would meet his associates, friends, or business partners and possibly their children. If you don't manage to find someone on your own, there is a good chance your future spouse will be selected from this pool. \n\nAs for marriage, if you are a teenage girl around the age of the film's protagonist you generally have two options: you meet a boy and get your father's approval, or your parents set you up with someone and you approve or disapprove. Despite the common conception that the father's word was law, many parents would have been willing to consider their daughters' opinions. This is especially true in the lower classes, where the stakes of marriage were not as high. That is, while the daughter of a duke or rich merchant may have been basically sold off to forge family alliances, a farmer or fur trapper would have wanted little more than a son in law who was well-raised, polite, and had a promising job, or a daughter-in-law who was attractive, healthy, and well-mannered (i.e. obedient--hate to say it, but that's how people thought back then). Research has found that in the Early Modern Era, love marriages were much more common among the poor than the rich."
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285h83 | What is the largest molecule, and how is a single molecule defined (as opposed to an amount of a certain compound)? | askscience | http://www.reddit.com/r/askscience/comments/285h83/what_is_the_largest_molecule_and_how_is_a_single/ | {
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"My guess (depending on your definition) would be some sort of plastic, seeing as how they basically form long chains from repeating units (*monomers* forming *polymers*). For plastics, this size can either be defined as the number of individual units (monomers) incorporated into the chain, or by the weight of the entire chain.\n\nTo answer the second part of your question, the size of a single molecule is typically defined by the weight of that single molecule. The amount of a certain compound may also be defined through weight (X grams of table salt, or sodium chloride), but the most common unit would probably be x amount of [moles](_URL_0_). \n\nFUN FACT: The largest protein (which is also a molecule, sometimes called biomolecule) is titin, which has the chemical formula: C^169723 H^270464 N^45688 O^52243 S^912",
"There are many types of polymers that could easily be called \"one molecule.\" Your base question amounts to \"what the largest number?\" the answer to which is of course always at least one bigger that the number you state. \n\nWhen molecules start getting into the tens of thousands in molecular weight they aren't really referred to as molecules anymore, but there is no definitional line at which this occurs, it's just practice. "
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dy1d3b | why does some movie theaters get to show a movie a day or two before it's actual release date? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dy1d3b/eli5_why_does_some_movie_theaters_get_to_show_a/ | {
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"They're called advanced screenings, and they have several purposes.\n\nThey're leveraged for publicity and marketing for many shows. A private screening for film critics means getting reviews out early. Including a few VIPs and well-connected people can build hype. A few people describing how they saw the show early and they loved it can help pump the excitement before the big launch.\n\nThey serve another useful purpose. They allow theaters to test that the movie is all present, that it is the correct movie, and that all the equipment is functioning normally before the big initial showing. Occasionally there are mistakes made, such as theaters being sent mislabeled reels or reels being incompatible with the viewing equipment. An advanced showing gives an opportunity to verify those things.\n\nIn some locations an advanced screening is required by law, since \"blind sales\" are prohibited. Somebody representing the theater must view it at least once to verify that they're receiving the thing they expected.\n\nThey can serve all the purposes above; the screening provides a teaser and advertising for the community, and it is a test of the equipment on a small scale, and it meets the terms of the law. \n\nFor some shows --- especially the shows of lower quality --- sometimes the advance showing is done privately, with no critics or private audiences except for the theater owner and only to satisfy the law and ensure the equipment works."
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6q0dhp | how are damages caused by disasters calculated and reported? how accurate should i expect them to be? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6q0dhp/eli5_how_are_damages_caused_by_disasters/ | {
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"Hi there molycow,\n\nJust as a disclaimer, I'm not an expert in disaster losses calculation.\nHowever, based on my experience from the hail storms that occurred in Sydney (it's happened many times, always every 2-3 years).\n\nUsually if you have insurance for your home or car, and your property is damaged you usually call up the company and they bring in an assessor. I'm not sure if that assessor is a third party, or is part of the company.\n\nFrom there, they usually estimate the damage, usually they might have other examples to go by. Though if this disaster hasn't been seen before, I would imagine that the process of estimating the losses would have to take longer.\n\nIf that is the case, I reckon they would get you to breakdown what losses have occurred and how much it has cost you.\n\nBut then again it really depends what type of damages your talking about. It could be damages to residential, commercial or industrial property.\n\nIf you include commercial/industrial you will need to take into account not only the damage that has occurred already, but also the losses that will occur as a result of not being able to continue business. Usually if this is a long period this cost can sometimes outweigh the costs of damages that were caused \"physically\".\n\nThen again you could expand to a whole city that has been affected by a whole disaster, which is a more difficult task to estimate.\n\nI'll probably leave it there for any other more experienced people to answer your question. But hopefully that provides some clarity to what you have been asking.",
"I have done damage calculations for FEMA for flooding in two scenarios:\n\nWhile a flooding event is going on, we take live data from water gauges, run them through models, estimate the size of flood waters, then calculate the number of structures (data quality varies) that intersect with the estimated flood extent, and take the estimated flood level. We run this many times as the flooding event unfolds. We figure out how many homes are impacted by 1-2, 2.01 - 5, 5.01 - 8, and 8+ feet of water. Unfortunately, I don't get to see what happens after we ship the data but I am told that the data really helps to better direct resources. Later the points (often tens of thousands) are checked for accuracy by comparing the damage estimation to aerial photography.\n\nAfter a flood event, (this is massively simplified) FEMA may supplement local communities work forces by sending building inspectors into the field. They spend about 15 minutes at each structure collecting the high water mark (the most important piece of data) and a few dozen characteristics of the building. It goes into software thay spits out a damage estimation. This goes to the local community who then uses it for permitting for reconstruction and whatever else. The structure owner has the opportunity to contest the determination (whether they think should have a higher or lower rating, it depends) with the local community. \n\nThe accuracy really depends in the data quality which is far from perfect but keeps getting better every year. "
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519pa8 | how does social science work? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/519pa8/eli5_how_does_social_science_work/ | {
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"Social science is very much a soft science. It is a science, in that the Scientific Method is applied to try and find facts. However, there is an inherent, recognized difficulty in accurately measuring and testing in these fields.\n\nPhilosophy itself, while under the umbrella of social science, is not necessarily a science. In fact, science itself is a form of Philosophy. Science is a set of rules and ideas that are used to evaluate the world around you. How do we then evaluate philosophy? Through the use of logic. Logic is probably the one Philosophy that is agreed on. Without it, all analysis becomes impossible. \n\nThe \"proof\" of a Philosophy is that it is logically consistent and has supporting evidence for its validity. As was mentioned earlier though, there are inherent problems in accurately gathering and analyzing evidence. The human brain is INSANELY complex. We understand some of the chemical reactions, but know one really knows how the brain does what it does or thinks what it thinks. Even without that, you need to filter out cultural and societal biases and deal with the reality of humans being dishonest about their thoughts and actions.\n\nGoing back to Social Science as a whole, some of it is well researched, and some of it is pure drivel. The best thing to do is go back to the original studies and experiments done. You will be surprised to see that many of \"truths\" about humanity are supported by poorly done studies with comically small sample sizes."
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1k6mmy | How far has the crown gone through the royal family tree to find the closest living relative? | I was doing my summer history project and I read something that reminded me about [this CGPGrey video](_URL_0_). In the video it says that the crown will go however far it needs to through the royal family tree to find a living candidate for the crown. What is the furthest "distance" the crown has had to go? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1k6mmy/how_far_has_the_crown_gone_through_the_royal/ | {
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"Depends how you look at the War of the Roses. In terms of the most distantly related successor, Henry VII was the third cousin once removed of Richard III. However, this took place in the Wars of the Roses when there were often several competing claims, and Henry claimed that Richard was never the rightful king in the first place (though Henry was still only the second cousin of the man he claimed was his rightful predecessor - Henry VI).\n\nScotland had a similar case in the late 13th/early 14th centuries where the main royal line collapsed and the Bruce and Balliol families (both of whom were only distantly related to the previous king) both claimed the throne and fought each other for it.\n\nIn the times of more clearly defined rules, Anne and George I were second cousins.\n\nIf you're looking for a case of a really large \"distance\" between monarchs, then look at France rather than Britain. Britain has a male-preference primogeniture succession law, which means that while men come first, women do count in the line of succession. France historically had what's called Salic Law, meaning only male ancestry counts. This means they've often had to go a longer way to pass on the crown. The biggest example of this was Henry IV, who was a *ninth* cousin once removed from his predecessor Henry III; their closest common male-line ancestor had died over 300 years before."
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1p1rsx | Did the 'Cult of the Feathered Serpent' play a significant role in the end of Mayan civilization? | I was watching a documentary on PBS called 'In Search of the Lost Maya' and, among other things, they mentioned (kinda offhand) how the 'Cult of the Feathered Serpent' was beginning to take hold in the northern regions of Mayan civilization just as their governmental structure etc was falling apart. I'm not sure how the two are connected...but this brings me to a couple questions. Did this "cult" play a large role? Were they generally accepted by society? Idk why but I always assumed from what I have learned that the feathered serpent (at least with the Aztecs in Quetzalcoatl), known to the Maya as Kukulkan (I believe) was already a part of their religion or had always been so, and not a 'cult'. This kinda upends my view on their religion as a whole.
Maybe I am just wondering why they referred to it as a cult, because I had not heard that before. I have since found other references that allude to the same thing, albeit that was for the Aztecs. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1p1rsx/did_the_cult_of_the_feathered_serpent_play_a/ | {
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"text": [
"No, not really.\n\nThe \"Feathered Serpent Cult\" is a name that archaeologists and iconographers have given to a pan-Mesoamerican explosion of imagery associated with Quetzalcoatl/Kukulkan dating to the Epiclassic period (around the time of the Classic Maya collapse). It appears to be a larger religious movement associated with sacrifice, the ballgame, and the nobility. It's most prominent in Central Mexican sites like Tula and among the cultures of the Gulf Coast such as the Totonac city of El Tajin. Some time during the Early Postclassic a group of people from the Gulf Coast (Putun and Itza peoples, specifically) migrated into the Northern Yucatan and created a kind of hybridized culture with the Maya who were living there. At this time cities like Chichen Itza begin to show an increased focus on Kukulkan and ballgames in imagery.\n\nAlthough it's tempting to see the Feathered Serpent Cult as a kind of Mesoamerican *opus dei*, that's not really accurate. I'm not even sure the word \"cult\" is a fairly accurate descriptor. Feathered Serpent Tradition might be better. Here's Susan Toby Evans (2008:386) discussing this cultural shift:\n\n > Turning to the central Yucatan Peninsula, the motivations for the intrusion of Central Mexican stylistic motifs are more difficult to recover. Large-scale migration seems unlikely. Religious proselytization, in the form of an emphasis upon Central Mexican belief systems, may have been an important factor, but seems secondary to both military conquest and securing trade routes.\n\nThis had virtually nothing to do with the collapse of Classic Maya centers, except that it happened at about the same point in time. The Maya \"collapse\" was fairly localized. The densely populated southern lowlands had a major demographic collapse, but the Northen Yucatan (where the Feathered Serpent \"Cult\" took hold) was largely not affected other than in the loss of trading partners.\n\n* Evans, Susan Toby. 2008 *Ancient Mexico and Central America: Archaeology and Culture History* 2nd edition. Thames and Hudson."
]
} | []
| []
| [
[]
]
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36tsg4 | why, despite the various laws against it, is vigilantism wrong? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/36tsg4/eli5_why_despite_the_various_laws_against_it_is/ | {
"a_id": [
"crh0p3v"
],
"score": [
5
],
"text": [
"Per the Constitution, accused criminals have a lot of rights. They need to be investigated by the police, tried by the DA, represented by a lawyer, found guilty by a jury, and sentenced by a judge. There's a lot of people involved in that, who should be making sure everyone else is doing their job correctly, and affording the accused their civil rights.\n\nWith vigilantism, you're removing the whole criminal justice process, and basically deciding guilt and punishment based on one person's whim."
]
} | []
| []
| [
[]
]
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