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7brri3
|
were there any French troops in Normandy invasion?
|
I was wondering if there were any French troops that landed during the Normandy invasion and if not why not seeing as it was to liberate their country
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7brri3/were_there_any_french_troops_in_normandy_invasion/
|
{
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"score": [
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"text": [
"Always room for more, but as a starting point there's [a thread from a couple of years back] (_URL_0_) where /u/k1990 covers ground units and I chip in a bit about the naval and air forces."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/2po4d1/what_was_the_french_contribution_to_dday/"
]
] |
|
62kt68
|
how do darknet dealers get drugs like cocaine and heroin in the first place?
|
Like where does the drug come from in the first place? How'd they make it and stuff?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/62kt68/eli5_how_do_darknet_dealers_get_drugs_like/
|
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"You just find a supplier and buy it with bitcoin, its actually real easy, took maybe half an hour to set up and make a purchase. I ordered over 20 times in large quantities and never got caught or lost a package",
"From drug suppliers, who get it from drug cartels.\n\nIllegal enterprise creates an entire underground economy.",
"The same way traditional drug dealers do. From producers, or importers (who get them from producers). The drug supply chain does not change, what changes is how the product gets to the end user.\n\nThink of it like Amazon vs a general store. They both buy products from suppliers and wholesalers but they retail the products very differently. ",
"My question is how do people actually get this stuff delivered? How is it not caught every time..",
"I recall checking out Silk Road when I first heard about it. Some of the sellers that had cocaine seemed to be buying large amounts of cocoa paste? I have no idea where it was getting refined or what the path/connection was. It was not industrial amounts though... my first thought was that someone was getting paste and producing it on a smaller local level. I could be wrong.\n\nAnyways.. it would get cooked up into large glass pans, probably lasagna or casserole pans and make these nice sweet bricks of pure coke. You could see the shiny/flake crystalline pattern that good cocaine will have on the close up shots of broken chunks. \n\nAnecdotal, but I thought it was pretty interesting how they showed their production process for authenticity purposes I suppose. Also interesting was the reviews section where buyers would rate the product and delivery experience etc. \n\nIf I recall correctly, the money transfer was held in escrow until both parties were satisfied. A sellers account needed to make so many confirmed sales before money would be moved out of escrow or too win a dispute. A buyers account also needed to have made several confirmed purchases before being able to win a dispute. All in all seemed like a pretty fair system and I think the favor usually went to the buyer if something was seized in the mail. \n\nI must have spent half a day just browsing silk road and all it had to offer. Never went back again.. it was simply window shopping.",
"Not a dark net thing persay, but... when I moved from NC to CA, I could only take so much with me on the plane. I stuffed all my other belongings in a single box. \n\nThat included various blankets, trinkets, movies, but 5 open bottles of alcohol, my glass pipe which I didn't realize had a freshly packed bowl in it. Sent it off via UPD with a fragile sticker all over.\n\nNothing actually happened though. It just showed up, no problem. ",
"Cocaine is made from coca leaves. Opiates (such as heroin) are made from opium resin, from the sap of poppy flowers.\n\nCoca is a bushy plant that is native to South America, and grown mostly there. (Coca is not to be confused with cacao, which is the plant that chocolate comes from.) Poppies are a flower that is native to the Mediterranean region, but is today most heavily grown in central and southern Asia.\n\nPoppy flowers that you can buy at garden shops are actually the same species as \"opium poppies\", and they do contain opiates. It's legal to grow them for decorative purposes, but not to extract opium from them. (The bright orange \"California poppy\" does not contain opium.) Similarly, poppy seeds that are used in pastries do contain a tiny amount of opiates. It's a myth that eating one poppyseed bagel will make you test positive for opiates on a drug test. However, some European pastries are stuffed with poppyseed-based filling and will certainly register on a urine test. A blood test can tell the difference between heroin (or fentanyl) and poppyseeds, though.\n\n(Historically, poppy seeds were a byproduct of opium production. Opium has been used as a medicine for pain since the dawn of recorded history in Europe. There are sculptures from Minoan Crete depicting the poppy as a goddess of healing. By the way, cannabis is from the Caucasus, and the Greek historian Herodotus was kind of weirded out by how the people there — the Scythians — used it: they would burn it in bonfires to get high on the smoke.)\n\nAnyway, these plants are grown secretly, or with the cooperation (bribery) of local governments. Extracting cocaine from coca leaves, or crude opium from poppies, doesn't have to be much more complicated than extracting caffeine from coffee beans or tea leaves. But for the drug trade, it's done with chemicals to make it faster and more efficient. Turning opium into heroin is a bunch more complicated and involves secret chemical labs. Opium is ancient, but heroin was only invented in the 20th century.\n\nExtracting opium from poppies involves letting the flower go to seed, and then scratching or cutting the seed-pod to make it ooze sap. The sap contains a mixture of many different chemicals, some of which are already drugs (primarily morphine) and others that can be chemically changed to make drugs. Extracting cocaine from coca leaves involves soaking them in water and chemicals to get the cocaine to dissolve out of the leaves.\n\nIt's worth noting that coca leaves and poppy extracts can be used as drugs without any further preparation. Native people in Colombia, Bolivia, and Peru have chewed coca leaves as a mild stimulant for thousands of years. The ancient Greeks and Persians used opium extracted from poppies with alcohol from wine. However, coca leaves and poppy pods are very bulky; refined cocaine and heroin are much more compact and therefore easier to smuggle.\n\nThere is a general rule that when drugs are made illegal, people find ways to make the drugs stronger, because stronger drugs are easier to smuggle. In the 1920s, when the U.S. prohibited alcohol, the production of beer and wine basically shut down, but gin and whiskey became more popular. Cocaine is stronger than coca leaves, and crack is stronger again than cocaine. Modern cannabis is much stronger than the \"Indian hemp\" that has been grown for thousands of years. Some of the opiates used today, such as carfentanil, are so much stronger than plain opium that they were originally invented not even as painkillers, but to be used in tranquilizer darts on elephants!"
]
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ec1b5e
|
whats the difference between sorting by best and sorting by top?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/ec1b5e/eli5_whats_the_difference_between_sorting_by_best/
|
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"Top: Highest score (Upvotes - Downvotes = Score)\n\nBest: [This is more complicated](_URL_0_). It takes all the current votes on a post as a sample and gives it a score that it is 95% confident it will end up with, given infinite time.\n\nEssentially, it prevents older posts with a higher score (simply because they were posted earlier) from pushing newer, popular posts all the way to the bottom of the page."
]
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|
[] |
[] |
[
[
"https://redditblog.com/2009/10/15/reddits-new-comment-sorting-system/"
]
] |
||
10ynow
|
How do eyestalks (such as on slugs) work? How do they retract and extend?
|
askscience
|
http://www.reddit.com/r/askscience/comments/10ynow/how_do_eyestalks_such_as_on_slugs_work_how_do/
|
{
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"text": [
"They inflate them with their haemolymph (or bodily fluid), and they have a retractor muscle, that when contracted, withdraws the tentacle."
]
}
|
[] |
[] |
[
[]
] |
||
uh8rr
|
How do we know the difference between good and bad?
|
I ask this question because I was listening to "Friday" by Rebecca Black. A thought popped into my head, how do we know the difference between good and bad songs, singing, and people?
|
askscience
|
http://www.reddit.com/r/askscience/comments/uh8rr/how_do_we_know_the_difference_between_good_and_bad/
|
{
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"text": [
"Its usually based on the frame of reference and other people. People are conditioned to think something is good or bad based on what they were taught as children. Therefore some people who grew up with parents who enjoy AC/DC think classical rock is better than hip/hop, so on so forth",
"Are you a trolling me? Your title caused me to expect something a little more intellectually deep than '\"Friday\" by Rebecca Black.'"
]
}
|
[] |
[] |
[
[],
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|
1jwtm3
|
Did the Rosenbergs committ espionage or was it an unfair trial during a period of fear?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1jwtm3/did_the_rosenbergs_committ_espionage_or_was_it_an/
|
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"I would say yes to both of your questions.\n\nMorton Sobell(tried/convicted with the Rosenbergs) admitted to spying in 2008 after maintaining his innocence throughout. Morton implicated Julius and said that Ethel was aware of what her husband was doing.\n\nMost of the strong evidence supporting the guilt of the Rosenbergs has arisen since the fall of the USSR which is why much of the criticisms of the trial and later execution remain to this day. \n\nFun fact: Lee Harvey Oswald claims one of the major influences in him becoming a Marxist was receiving a pamphlet protesting the Rosenberg execution.\n\nSources:\n_URL_1_\n\n_URL_0_\n\n_URL_2_",
"Confirmed spies. PBS has information on the Venona Project, which revealed a lot about atomic-era spies' activities. [read about it here](_URL_0_)",
"I actually did a mock Rosenberg trial during my degree program thanks to a Professor who tried to keep things interesting. I can only speak as someone who studied the trial transcript and its immediate sphere available [here](_URL_0_) but there are some fairly obvious conclusions. Julius unquestionably was a Soviet Spy. Not a very good or effective one, and he leaked very little that might even be remotely useful to the Soviets, but he was definitely a spy. Equivocal in this certainty, there was not nearly enough evidence to justifiably convict Ethel on the same charges as her husband in an objective court. The case against Ethel is based entirely on the testimony of Ruth Greenglass, whose testimony dramatically changed to indict Ethel between the preliminary hearings and the actual trial. While Ethel almost certainly knew what Julius was up to, there is no reasonable case to be made ascertaining her guilt to the same degree.\n\nWorth noting, the Judge did not want to give Ethel the death penalty and did so only after much illegal browbeating by famed prosecuting attorney Roy Cohn. This infamous incident lead to this [famous clip](_URL_1_) in Angels in America.\n\nEqually important to note: if Julius had rolled over and named names like Sobell did, he and his wife would have survived with mild if any punishment. He died the only member of a mildly ineffectual spy ring who didn't compromise his principles in the face of prosecution - many feel that Ethel was given the death sentence by the powers that be purely in order to make an example of what happened to those that didn't talk. They left children behind.\n\ntl;dr: Yes Julius was a spy, but not a very effective one. Ethel almost definitely knew what Julius was up to and should legally have served time, but was railroaded onto Death Row.",
"Julius was a confirmed spy. There is really no doubt about that at this point. \n\nEthel's involvement seems much more marginal and unclear. She knew what Julius was doing, but she didn't seem to be an active participant. \n\nAs for the trial, it was both somewhat unfair and somewhat botched. The government's public case revolved entirely around testimony of Ethel's brother, David Greenglass. The Greenglass testimony was never adequately cross-examined, and the Rosenbergs' attorney did a pretty lousy job of dealing with the evidence in question. (Why? I suspect he had no idea what to do and was very intimidated by the technical aspects. The government declassified the idea of implosion _specifically_ to use it as evidence in the Rosenberg trial. The Rosenbergs' attorney, instead of bringing in experts to ask whether Greenglass' crude sketch was very valuable or not, instead argued [that the declassified drawing should be impounded into court record so that nobody else could see it.](_URL_0_) Whatever he was trying to accomplish by that, it didn't work.)\n\nGreenglass himself later admitted to perjuring himself (to implicate Ethel more strongly) in order to cut a deal with regards to his own wife. All of this could have come out with decent lawyering by the defense, but it didn't. \n\nThe government's _secret_ case, via the VENONA intercepts, was much stronger. But this could not be introduced into evidence without compromising the source. Hence the reliance on Greenglass. (And Harry Gold, who is another complicated character.)\n\nDid the Rosenbergs deserve their sentence? Maybe Julius, if you're into capital punishment for this sort of thing. Ethel, probably not. But one also has to ask, given what we know today, why both of them were willing to go to their graves for having spied for Stalin, when they both knew that if they cooperated with the government they'd have been given lighter sentences. The entire point of the capital punishment charge was to coerce them into cooperating, and they pushed it as far as they could. This despite having two children. One wonders what fueled this devotion to their cause.\n\nThe question of anti-Semitism sometimes comes up. I would suggest that it played a role in the media discussion of the trial (many of the stories on the trial were full of racial innuendo, with an undue focus on the defendants' corpulence and physical passion), but that in terms of actual judicial conduct, it's not so clear. The prosecutor (Irving Saypol) and the judge (Irving Kaufman) were both Jewish (which doesn't necessarily prove anything, but does countermand the assertion that it was some kind of WASP conspiracy). The government's case was, we now know, based on pretty firm evidence, although they did not introduce that into court. I don't really see any evidence that anti-Semitism played a huge role in the actual prosecution of the matter. The accusations of anti-Semitism were part of the pro-Rosenberg campaign that was largely orchestrated by the Communist Party at the time. The CP had a wonderful tradition of trying to create martyrs to their cause, something which had a long-term, devastating effect on Leftist politics in the United States.\n\nAs for the actual value of the Rosenberg's information to the USSR, the atomic bomb work passed on by Greenglass was of minimal importance. At most it confirmed that some of the other spy data the Soviets were getting wasn't totally made-up, but even if they hadn't existed, there were other spies (e.g. Ted Hall) who could have served the same function, and in any case, the Soviets didn't swallow the espionage without vetting it anyway. Their spying on other war technology (e.g. the proximity fuze) might have been more consequential. Greenglass had too basic an understanding of the atomic bomb work to be a very good spy of it.\n\nIt's worth noting, perhaps, that the spy Klaus Fuchs, who gave the Soviets _much_ more useful and detailed information about American and British nuclear developments, over a much longer timespan, was sentenced to a maximum of 14 years in prison in the UK, and then let out after 9 years to emigrate to East Germany. Why such a light sentence? In part because he cooperated, but also because in the UK, they distinguish between spying on an ally and spying on an enemy — the USSR was, after all, an ally during the Manhattan Project, and only later became an adversary. Just a side note on comparative approaches to espionage.",
"They almost certainly committed the legal crime of espionage (while Ethel's overt acts may have been less important than her husband's, the American legal system provides for full accomplice liability). I'd say their trial was fair in the sense that it met the applicable legal standards for the time. There is considerable criticism of their legal representation, but the Rosenberg's chose their own lawyer and nothing he did resulted in reversible error.\n\nToday, there would be sentencing issues (the rules for a death sentence have changed significantly since). However, it was a fundamentally fair trial using the standards of the time.",
"One excellent source on the topic is *Spies* by Haynes, Klehr, and Vassiliev. It combines American, European, and Russian sources (from that brief window of unrestricted access to KGB files between the fall of the Soviet Union and the rise of Russian nationalism) to create a broad narrative of KGB activities in the United States. While that doesn't address the second part of your question, I would argue the answer to both of your questions is \"yes\" at the same time. That is, Julius Rosenberg was definitely guilty as established not so much by the mess of a trial but rather by the release of the Venona decrypts decades later and the KGB files in the 90s. His wife was clearly aware of his activities (as per Soviet sources as well) if not a direct participant, *and* it was practically impossible for them to get a \"fair\" trial. I don't think it was so much a question of fear as of trying to figure out what constituted a proportional punishment for a central role in stealing the a-bomb; I think that's a place where reasonable people have trouble coming to a \"fair trial\" conclusion if they place any weight on the national interest. \n\nAs mentioned by other posters, the only way out of the death penalty was cooperation, and they apparently had other priorities. "
]
}
|
[] |
[] |
[
[
"http://www.coldwar.org/articles/50s/TheRosenbergTrial.asp",
"http://www.nytimes.com/2008/09/12/nyregion/12spy.html?_r=0&partner=rssnyt&emc=rss&pagewanted=all",
"http://jandersonthomson.com/wp-content/uploads/2009/10/Oswald.pdf"
],
[
"http://www.pbs.org/wgbh/nova/venona/intercepts.html"
],
[
"http://law2.umkc.edu/faculty/projects/ftrials/rosenb/ROS_TRIA.HTM",
"http://www.youtube.com/watch?v=Gp8VDUg5uEY"
],
[
"http://atomland-on-mars.com/greenglass-secret-of-the-atomic-bomb.html"
],
[],
[]
] |
||
1pbo34
|
I have to complete a research essay on African history before 1800 and need a good essay topic. Any ideas?
|
Second year history course. Paper length is 12-15 pages.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1pbo34/i_have_to_complete_a_research_essay_on_african/
|
{
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"text": [
"That's pretty broad. What are you interested in?",
"What aspects of history are you interested in? Economic history? Religious history? Urbanization? State-building? The interaction between culturese (Europeans or Arab world interacting with African cultures)? The \"Great African States\" like Mali, Songhai, Bornu, Kush, Zimbabwe or Aksum?"
]
}
|
[] |
[] |
[
[],
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|
38bif8
|
Can someone give me a quick overview of how the Caliphates transitioned into one another?
|
EDIT: Alright, I'm asking because I'm just curious on Middle Eastern history. I'm wondering if each of the Caliphates were like different dynasties with families, or were they different ethnic groups, things like that. How did one Caliphate surpass another?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/38bif8/can_someone_give_me_a_quick_overview_of_how_the/
|
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"Is this a homework question? If not, could you please provide a little bit more information about what you're looking for?",
"A short (believe me, I tried to be as concise as possible) answer to a very broad question is:\n\nAfter the Prophet Muhammad died (the traditional date, sometimes questioned by modern historians) in 632 C.E., the succession of leadership went to Abu Bakr, a well known and respected companion of his. This succession didn't go uncontested, as a number of people thought that Muhammad had already explicitly named a successor through his son-in-law and first cousin Ali ibn Abi Talib, but it seems that Ali himself did not immediately press the issue, since Abu Bakr also had the support of Umar al-Khattab, another famous companion of Muhammad's. Abu Bakr titled himself as Khalifat Rasulillah, or the \"successor/deputy to the Messenger of God\" and was the first Rashidun Caliph. After Abu Bakr came Umar, then Uthman (who was from the Umayyad family, but had taken Muhammad's side during the early years of Islam) and the finally Ali. These four were all Arabs from Mecca, all belonging to the tribe of Quraysh. Ali was Muhammad's own blood, belonging to the Hashimid family within the tribe of Quraysh. The Umayyad family was a distant cousin family to them.\n\nDuring Ali's caliphate there were several issues, the biggest of which was an Umayyad rebellion due to unhappiness with how Uthman's caliphate had ended (Ali never punished Uthman's assassins, which to the Umayyads was as good as official sanction, though traditions indicate he had sent his son Hussayn to protect Uthman during his last days). The Umayyad rebellion was led by Mu'awiya, the governor of Syria.\n\nIn any case, Ali was killed while praying in Kufa, and Mu'awiya quickly seized the reigns of the Caliphate. This was the beginning of the Umayyads, who then ruled from Ali's death in 661 C.E. to 750.\nThe Umayyads were Arabs, and very pro-Arab in their policies. They adopted the ruling customs of many of the structures left behind by previous conquests, and it took a while for them to introduce Arabic as the government language. They did not encourage conversion, and sought to keep the ruling Islamic clique as Arab as possible. This led to a lot of issues with regions in Mesopotamia and Persia, which had many Persians (and one generation later, mixed ethnic Persian/Arabs or Persianized Arabs) and was a hotbed for anti-Umayyad sentiment. Particulaly strong also was Shi'a discontentment, since the Umayyads were not very kind to Ali whom the Shi'a saw as the rightful Caliph. The Shi'a supported various sons of Ali in the wake of Ali's death - some supported Hasan ibn Ali, who did not take up arms against the Umayyads. When Hasan passed away, they supported Hussayn, who DID take up arms, and was massacred with his entire family save for one son and one sister. These two brothers were special in that their mother was Fatima, Muhammad's daughter, unlike some of Ali's other sons through other wives. Yet others still rallied around a son like that, a nephew of Muhammad rather than a grandson through Fatima, named ibn Hanafiyya, this rebellion too was defeated. Shi'a sentiment remained powerful in Mesopotamia, particularly in Kufa.\n\nThe Abbasids relied on the pro-Arab and anti-Shi'a policies of the Umayyads to gather support among Persians, non-Muslims, and Shi'as to launch their rebellion in Khorasan. The rebellion was very secretive, and only when it was sprung was the identity of their candidate, the future Caliph as-Saffah, revealed. The Abbasids rose in revolt in 747 and by 750 had destroyed the Umayyads almost completely. However, one Umayyad managed to escape to Spain and set up an Umayyad caliphate there.\n\nThe Abbasids fixed many of the issues that plagued the people who had risen in their favor, but not the issues of the Shi'a. As-Saffah was similarly related to Muhammad as the Alids were, as As-Saffah's ancestor Abbas was Muhammad's uncle, like Ali's father. However, Ali's sons were Fatima's sons as well, and thus directly descended from Muhammad, rather than from an uncle or so like the Abbasids. Shi'as were still angry and were upset that their head, Ja'far as-Sadiq, had not become Caliph.\n\nJa'far as-Sadiq lived a peaceful existence as the head of the majority of Shi'as, He was the great-grandson of Hussayn ibn Ali, through Hussayn's son Zayn al-Abideen who survived the Karbala massacre. Ja'far died in 765, but his death was followed by another succession issue. His designated heir, Isma'il, had either disappeared or died before his father, and there is no concrete evidence that Ja'far ever nominated another successor. This is a thorny issue, since the Shi'a concept of Caliph and Imam is ma'sum, or infallible, meaning the Caliph/Imam can do no wrong. How could Ja'far appoint a son who died before him? The only answer to some was that Isma'il had become Imam, and that his son Muhammad was now the next Imam. Others believed that Musa Kadhim, another son of Ja'far's, had become Imam. Muhammad ibn Isma'il's supporters became the Ismaili Shi'a, and Musa's supporters were the Ithna Ashariyya, or the Twelver Shi'a. \n\nUltimately, Musa's line did not achieve a caliphate, since the Twelver Imams were more or less political prisoners within the Abbasid state. Shi'a sources say that they were poisoned by the Abbasids. The last Imam went into hiding, and Twelver belief to this day is that the Twelfth Imam will return as al-Mahdi, or the savior, to redeem his people.\n\nThe Ismailis on the other hand took a page out of the Abbasid revolutionary book, went underground, and began a caliphate-wide conversion mission. At the break of the 900s, the head missionary of the group, a fellow named Abdullah (almost certainly NOT his real name, since the Ismailis used non-descript revolutionary names like the Abbasids had) broke cover and said that he was al-Mahdi and the great-great grandson of Muhammad ibn Isma'il. By this time the Abbasids had lost some power and were less centralized, and the rulers in Africa in their name were unable to fight back against the army the Ismailis had amassed by converting the Kutama Berbers to their cause. For the only recorded time in history, there was a powerful Shi'a caliphate in existence as the Fatimid Caliphate. Al-Mahdi's descendants ruled well into the 1100s but power really left the hands of the Caliph-Imam after the death of al-Mustansir. al-Mustansir's son Nizar was his designated successor, but palace intrigues led to the vizier supporting Nizar's younger brother Mustaali as the Imam. The vizier (name escapes me, I believe it was Malik al-Afdal) imprisoned Nizar and had him executed, but supporters of Nizar claimed to have smuggled Nizar's son to Persia. A string of powerful viziers ruled the caliphate and the Imam was more or less a figurehead. The Nizaris might have gotten their revenge, because al-Afdal was murdered, but Ibn al-Qalansi writes that it wasn't the \"Batinis\" (another word for the Ismailis) who were responsible. Under that authority they set up the Nizari state in Persia, and launched the Alamut period of Nizari Ismailism. al-Mustali's successors ruled in Egypt until Salah al-Din Yusuf ibn Ayyub put an end to the Fatimids in the 12th century.\n\nThe Abbasids by this time had lost a great deal of power (for the same reason as the Fatimids - the loss of centralization, concessions to local rulers and emirs, and the reliance on Turkish mercenaries and soldiers and governors that weren't always the most reliable. However, the Abbasids continued to exist well into the middle 13th century until the Mongols wiped them out with the sack of Baghdad. The Mamluk Sultanate that sprang up in Egypt around that time (1250's and 1260's) kept an Abbasid Caliph in Cairo as a religious figurehead, but the power remained with the Mamluk Sultan.\n\nBeyond the sack of Baghdad my knowledge of Islamic history is limited, so I will defer to others."
]
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[],
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46f9oq
|
can we really clean pesticide off fruit by just rinsing them off? wouldn't that mean rain would rinse it off all the time?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/46f9oq/eli5can_we_really_clean_pesticide_off_fruit_by/
|
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"You're not cleaning off the pesticide. You're cleaning off dirt and other toxins that may have stuck to the wax they put on the fruit to make it shiny.\n\nPesticides stick to the fruit, but they are also absorbed by the plant and end up within the flesh of the fruit. ",
"Rinsing is for removing contamination, especially for removing feces from fertilizers, irrigation systems and sloppy storage. You don't get all the bacteria off from it, but removing any large clumps should reduce the load to where your body can fight off any of the rest.",
"Primarily I wash my produce because I have no idea who touched it before me. Did the employee stocking the produce section wash his hands after he sneezed? How about the other shoppers who are picking up and touching produce while they look for the very best apples in the display? Or the people who packed it for transport to the store? \n\nNot to say that washing them won't also remove any residual pesticides on the surface. However, I recall reading about how pesticides are very water soluble and for this reason are applied following rain events or watering. ",
"There are different types of pesticides. There are systemic pesticides and contact pesticides. The contact pesticides stick to the surface, the systemic are absorbed by the plant. You cannot rinse a systemic pesticide from the plant.",
"I don't know about you, but I wash my dishes with scalding hot jets of water for 2-3 hours, and I wash my fruit with a gentle stream of cold water for 3-5 seconds.",
"It's not that they spray pesticides and get them all over the fruit and you take them home and have to wash it off. The sun took care of most of that for you by breaking down the chemical chains that kept the pesticide together. Most of them are designed to do their job a short while, and then break down into less lethal bits and pieces. \n\nThe danger comes from what the plant does with the pesticide and whether it was water soluable or not, whether it got into the soil or not, and whether the plant absorbed some of it while it was growing or not. If it did absorb some, then it's not broken down by sunlight. \n\nHowever, many pesticides have little to no effect on human beings so there is little to worry about. Unless you are an invertibrate they will have little effect on a person or in some cases they might get you high. Take nicotine and caffeine for instance, both natural pesticides, both go great with a bagel. ",
"Actually, pesticides aren't really the reason we rinse fruit. The biggest danger are actually bacteria and virus like E. Coli, Salmonella and Norovirus.\n\nContrary to popular belief there's actually a bigger risk of these things in organic products than conventional.",
"Like was said you are not washing off the pesticide or fungicide but washing off the dirt and contamination that happens from the picking of the fruit/vegetable to your house.\n\nAll pesticides/fungicides and herbicides have a PHI (pre-harvest interval) meaning that the farmer is not allowed to harvest the fruit until that interval it up. That interval is tested thoroughly by government agencies before the chemical is allowed to be used. It also means that once that interval is up there shall be no traces of the chemical in or on the fruit (It just breaks down and away much like your body breaks sown and away poisons you ingest). \n\nSo, for example, if the farmer sprays the crop with chemical X, and chemical X has a 14 day PHI he cannot harvest prior to that date at which time the chemical will be gone completely from the produce.\n\nNow you may ask what about countries that do not have such strict rules, well all fruit that enters USA/Canada and I assume the EU are randomly tested when they both enter the country and in some cases when they leave the country of origin. If a batch is found to have contamination from the chemicals it is very, very bad news for the shipper/producer and supplier. The entire shipment will be sent back and large fines as well as other consequences. It is far too risky for the farmer to cheat.\n\n\nSOURCE - lifetime fruit farmer.\n\n",
"Plant biology person here. There are actually some pesticides that you can rinse off and actually come off from rain.\n\nThere is two broad categories of pesticides. One of them are systemic pesticides. Systemic pesticides are absorbed and can't be washed off.",
"When I grew weed we stopped putting pesticides on a month before harvest to supposedly cleanse them. ",
"Rain DOES indeed rinse pesticide off. I live in the heart of \"Apple Country\" here in Ontario Canada. Every single time it rains (or sometimes even after heavy dew), the Orchard owners are out there spraying. \n\nAs another piece of colloquial evidence, I have two apple trees in my yard. I was told I had to spray after every rain, but I just couldn't be bothered. Every year (for maybe 6 years), I would get fruit, but it would get fungus and fall off (all of it, both trees - one mac, one spartan). \n\nOne year I bought some spray, and did the spraying (by hand, with a bottle - they are miniaturized trees), and indeed, I ended up with great fruit the the squirrels and birds were happy to eat, just before it was ripe enough to pick! \n\nThat said, it was a total pain in the ass, and apples are under $2.00 / lb, so I've never done it since :) \n\n* Note that fungicide AND pesticide are generally done in one spray * ",
"you don't wash off pesticide. But the level of pesticide you ingest is so insignificant that it won't cause harm to the body."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
||
zsoq8
|
What kind of atoms are present in a vacuum?
|
In interstellar space, there is about one atom per cubic meter... what kinds of atoms are they? Is this a stupid question?
|
askscience
|
http://www.reddit.com/r/askscience/comments/zsoq8/what_kind_of_atoms_are_present_in_a_vacuum/
|
{
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"text": [
"_URL_0_\n\n > Of the gas in the ISM, 89% of atoms are hydrogen and 9% are helium, with 2% of atoms being elements heavier than hydrogen or helium, which are called \"metals\" in astronomical parlance",
"Not a stupid question. But yes, like others said, it is mostly hydrogen. In fact, hydrogen is the most common element in the Universe. It was the first element to be created in the early Universe - all it required was that the Universe cooled sufficiently (due to its expansion) to allow electrons to orbit around protons. A good amount of helium was also made at that time (and trace amounts of Lithium, etc.). Heavier elements are generally only formed in stars, as you may know. Then they are scattered throughout the interstellar medium when the star dies, through various processes. So it is possible that an atom out in the vacuum you're talking about will be something other than hydrogen. But by default, in a sense, any 'random' atom out there is probably going to be hydrogen. "
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Interstellar_medium"
],
[]
] |
|
bg3rzi
|
how does illiteracy work?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bg3rzi/eli5_how_does_illiteracy_work/
|
{
"a_id": [
"eli361x",
"eli4if8"
],
"score": [
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3
],
"text": [
"Can you elaborate on what you mean? Because illiteracy is the natural state of humans.",
"If you’re asking WHY people are illiterate, there are a ton of different reasons. For the older generations, it wasn’t as frowned upon to quit school to work to help your family. Sometimes the school system fails students. Sometimes people have problems like dyslexia that can make them decide that learning is too much trouble, especially when they don’t have teachers willing to really work with them. \n\nI work with a nonprofit dedicated to adult literacy, and those suffering from illiteracy are often impoverished because their work options are limited. In the United States, there are over 36 million adults that are considered functionally illiterate (basically, illiterate to the point where they can’t even fill out a job application) and some never seek out the resources to help them become literate because there’s such a stigma surrounding adult illiteracy."
]
}
|
[] |
[] |
[
[],
[]
] |
||
3c30ut
|
What actually happens when a computer, server, or phone crashes?
|
im new to the sub, and this is what intrigues me. Computer science is allowed, right?
|
askscience
|
http://www.reddit.com/r/askscience/comments/3c30ut/what_actually_happens_when_a_computer_server_or/
|
{
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"csrw48q",
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"text": [
"This is an extremely broad question. It depends on what the device is, what it's purpose is, and what the problem is. There are so many possibilities it is quite difficult to list them all. Here are some examples though:\n\n**Soda machine stopped giving soda.** The [embedded computer](_URL_3_) in a vending machine is very tiny, and for the most part, very stupid. It can tell which soda you want based on what button you pressed, and it tells the machine which can to release. It also gives you change. But that's it. It can't do anything else. This kind of computer is most likely built on a single chip on a single circuit board. It does not have an operating system--just some code that continuously runs. If there are any mistakes in this software, it will \"crash\", or just stop working because the code confused itself. It will have to be manually reset. This usually means the computer is stuck in an infinite loop or is trying to do two things at the same time and simply can't. For example, an especially poorly designed system will become confused when you press two soda buttons at the same time, and will be forever stuck trying to decide which one to give you first. Or, when trying to calculate change, a bug in the code says to return zero coins when it has already been determined that *some* change is required. However, the software is already waiting for coins to be dispensed before releasing a soda, so it becomes stuck.\n\n**Your laptop just blue screened.** This means Windows (or whatever) detected a problem so bad that it can't fix it. This usually means that some device (say, an external hard drive) just tried to do something that is not allowed, like forgetting to give control of some important data back to the OS. The [OS panics](_URL_4_), and shuts down immediately to try to prevent further damage, such as the external hard drive grabbing even more important data. Alternatively, there may be something very bad happening to the hardware, like the CPU is way too hot or something is short-circuiting. Again, the system \"crashes\" in an effort to preserve itself. Less extreme crashes are caused by programs not responding. This is almost universally caused by programming mistakes. As an example, your internet browser and a game are both trying to control your audio output (even though they should work together). [Both are stuck](_URL_6_) trying to send data to the resource, but neither of them ever do because they are waiting for the other to do the same thing. They both \"crash\".\n\n**The Curiosity rover on Mars just froze.** This is a Pretty Bad Thing. No computer tech can go out and press the reset button. This is why just about everything that has ever traveled into space has two identical computers, so that one can keep chugging along and reset the other when there is a problem ([link,](_URL_1_) [link](_URL_0_)). Usually computer problems in space are caused either by tricky, unexpected circumstances in software, or hardware damage due to radiation. NASA goes balls to the wall when testing their code, and try to account for every possible thing that can go wrong. However, things happen. The rover might detect it is about to do something potentially dangerous, stops, and goes into safe mode. This is the space-equivalent of blue-screening. Alternatively, a cosmic ray (or other form of radiation) may [flip a bit in computer memory](_URL_5_). This causes unexpected errors and is currently a [big problem to work around](_URL_2_). For example, the engineers may have inserted a piece of code limiting the rover's speed to 10 cm/s. Theoretically, a flipped bit could change this to 10,000 cm/s. Even worse, a hard coded limit on the maximum limit of rotation on Curiosity's robotic arm could be changed from 90° to 900°. Any attempt to park the arm or use it could permanently damage the arm or its motors. Hence, the rover's memory is scanned for such errors continuously.\n\n**edit:** links\n",
"There's a billion things that could be wrong but there are typically three main classes of problems.\n\nFirst up is hardware. Something got too hot, something shorted out, something got disconnected, etc.\n\nThe second class of problems is software. Ran out of memory, the program is in an infinite loop, the program tried to do something it can't do or isn't allowed to do, basically the computer can't do what it was told to do so there is unintended behavior.\n\nLastly you have network issues which aside from bad connections are mostly the same as software issues.\n\nComputers are complicated and most of the time when someone is fixing a computer they're just better at googling than you."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Comparison_of_embedded_computer_systems_on_board_the_Mars_rovers",
"http://www.cnet.com/news/slow-but-rugged-curiositys-computer-was-built-for-mars/",
"https://en.wikipedia.org/wiki/Radiation_hardening",
"https://en.wikipedia.org/wiki/Embedded_system",
"https://en.wikipedia.org/wiki/Kernel_panic",
"https://en.wikipedia.org/wiki/Soft_error#Cosmic_rays_creating_energetic_neutrons_and_protons",
"https://en.wikipedia.org/wiki/Deadlock"
],
[]
] |
|
20hqb8
|
Finding the potential power a city may produce if it had installed solar PV panels in a certain capacity?
|
There are several calculators online that will readily do this, but I need to produce hourly results over an entire year. If I have data such as hourly solar radiation on a horizontal surface in Watt-Hours per Square Meter, what else do I need to find out how much power a particular location could have generated because of x capacity of solar pv, or y capacity of solar pv etc. (So the variable is how much capacity I have)
Any help would be greatly appreciated!
|
askscience
|
http://www.reddit.com/r/askscience/comments/20hqb8/finding_the_potential_power_a_city_may_produce_if/
|
{
"a_id": [
"cg401oy"
],
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"text": [
"%solar PV efficiency (eg. 18-22% is typical for consumer installations). You can multiply irradiance by this number to get the amount of energy produced and multiply this by surface area of solar PV to get the total energy consumption per hour.\n\nMost statistics provide solar PV installation as Wh values, which isn't helpful for this method of calculation. I'm not sure how you'd climb that hurdle.\n\nYou might also want to find a solar PV adoption rate so that you can change the surface area of PV with time."
]
}
|
[] |
[] |
[
[]
] |
|
3i8vgu
|
how do the genetics of three-parent children work?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3i8vgu/eli5_how_do_the_genetics_of_threeparent_children/
|
{
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"text": [
"We usually just think of our DNA as just being stored in the nucleus, but that's not the case. The vast majority is there, but some organelles also have their own, unique DNA. That's actually the basis of one of the theories on how we came to develop organelles, endosymbiotic theory. Basically, it's the idea that some/many of our organelles, like mitochondria, were originally separate single celled organisms, which were then essentially devoured or merged into what would become eukaryotes.\n\nAnyway, the third parent in this situation donates an egg, which contains mitochondria and various other organelles, but has had its nucleus removed. Then the nucleus of an egg from the other female parent is placed inside it, and sperm containing DNA from a third parent is added.\n\nAFAIK, it's always been two women, one man so far, but you should be able to perform the procedure with any three people. It would just involve additional steps to move the DNA around into sperm cells or eggs or whatever."
]
}
|
[] |
[] |
[
[]
] |
||
633gj6
|
what computer language is artificial intelligence written in and is it enough?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/633gj6/eli5_what_computer_language_is_artificial/
|
{
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],
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"text": [
"One computer language is equivalent to another in terms of what they *can* do, but AI has historically been associated with Lisp, Prolog, Java, C, and Python. There's no reason you can't do it in whatever language you want, of course. "
]
}
|
[] |
[] |
[
[]
] |
||
2caliu
|
Race & Slavery in Brazil
|
I was wondering if anyone could direct me to some good sources for understanding the history of slavery in Brazil and the history of Brazilian racial dynamics. I'm interested in comparing those topics to their counterparts in the United States, and I'm looking for sources that give a good overview of the topics.
Washington Post columnist Eugene Robinson wrote a book called *Coal to Cream* where he described a vacation he took to Brazil some years ago. He gave a broad overview of some of the racial dynamics there, and suggested that the national narrative was that there was so much race mixing in Brazilian history that everyone is highly mixed, thus creating one Brazilian ethnicity. Robinson suggested that this was visibly untrue, and that he was easily able to identify racial categories on sight the way we do in America, but that people nevertheless seemed to largely buy into this national narrative. I'm wondering if this is an accurate assessment of things.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2caliu/race_slavery_in_brazil/
|
{
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"cjdnsrt"
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"text": [
"I would recommend Chica da Silva: A Brazilian Slave of the Eighteenth Century by Júnia Ferreira Furtado as a good place to start along with Inhuman Bondage by David Brion Davis (He devotes a chapter specifically to Brazil). \n\nI think a film that really bears out what Robinson was getting at is City of God. If you have ever watched the film, the characters that are involved in criminal activity are almost all black and there is even an attempt by Benny, one of the drug dealers, to whiten himself (dying his hair, wearing American clothes, and wanting to be a farmer) when he decides to leave the criminal enterprise. Basically, there are evident racial divisions in Brazil no matter what any narrative might say otherwise. "
]
}
|
[] |
[] |
[
[]
] |
|
288hcc
|
how can businesses like airbrush booths use licensed icons, logos, or characters legally?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/288hcc/eli5_how_can_businesses_like_airbrush_booths_use/
|
{
"a_id": [
"ci8hp89"
],
"score": [
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],
"text": [
"They don't. \n\nFor instance all that Calvin and Hobb's stuff, everything made is stolen, no merch has ever been liscenced."
]
}
|
[] |
[] |
[
[]
] |
||
1n2m4h
|
what is at stake in the us senate filibuster by ted cruz that has been going on all evening?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1n2m4h/eli5_what_is_at_stake_in_the_us_senate_filibuster/
|
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"He is attempting to make a point about how serious he feels it is to oppose the Affordable Care Act, and holding up the business of the Senate, but other work can proceeded elsewhere and he is not preventing any votes from being held. This can not effect the Affordable Care Act itself, as that is already law. It is purely a symbolic stance. The only thing at stake appears to be his dignity. ",
"[Absolutely nothing.](_URL_0_) The vote will happen regardless, because what he's doing isn't a filibuster. And even if he could somehow prevent the vote, Obama care is still funded regardless. This is about getting Ted Cruz in the papers and nothing more. ",
"I wanted to make an offshoot about this. Can somebody ELI5 why, besides partisan lines, republicans are really so against the affordable care act? I feel like in my own life it has already helped me and will help me, yet a group of politicians are trying incredibly hard to deny this from staying in effect. ",
"Absolutely nothing. \n\n1. The affordable care act is already law, and much of the money funding the act is \"mandatory spending.\" ELI5 - a government shutdown or \"defund Obamacare\" bill would not impact it.\n\n2. The senate is poised to take up a bill from the house that prevents a government shutdown and defends Obamacare, but it hasn't been introduced yet. Debate hasn't started. That means that no matter what the Senator does he'll have to STFU when the Senate makes a \"motion to proceed to debate\" of the bill. Most senators filibuster bills while they are being debated, FYI.\n\n3. It's a pretty shitty position He's putting republicans in. Essentially he's asking them NOT to vote for a bill that prevents a government shutdown (something everyone wants to avoid) and defends Obamacare (something every republican wants). A no vote would easily be spun during the elections, used to accuse republicans for voting to shutdown the government. The republicans in the senate don't want that getting in the way of their chances for taking over the chamber in the next election cycle.\n\nThe sad part is that Senator Cruz knows all of this, but will use the risks of shutting down the entire government to make his point about Obamaxare being bad and (in my opinion) get some media attention as a conservative darling before he officially announces his run for President.",
"Ugh, I heard about it this morning on the radio in Germany. The only clip they played was him reading Dr. Seuss and how he isn't helping the tarnished image of congress being one of the least productive in history.",
"Nothing is at stake, except to prove what pieces of shit the Tea Party animals are. There will be no difference no matter what he does or says.",
"I keep reading that it's not a true fillibuster. I'm not absolutely certain, but I think that's because Senate rules do not allow filibustering on an appropriations bill. ",
"It technically isn't a filibuster because it will get voted on no matter what. \n\nEither way keep it up Cruz. ",
" > For states that do expand Medicaid, the law provides that the federal government will pay for 100% of the expansion for the first three years and then gradually reduce its subsidy to 90% by 2020. \n > From: _URL_2_ \n\n \n > The states themselves will not receive the federal funds. The money will be given to hospitals and providers, but after 2016, states will have to start contributing their own funds to the program. \nFrom: _URL_1_ \n\nTexas (rightly) says that the federal government is passing a law that greatly expands medicare and obligates states to pay for something they cannot afford. This is socialized medicine. \n\nYou may think Texas is not capable of making a difference here, but you should think again. \n\n > One out of four Texans do not have health insurance -- the largest percentage of uninsured in the nation -- and leaves the state with over 6 million potential customers for the health insurance exchanges. \n\n > With so many people potentially signing up for health care, Texas could make a strong case for the ACA's success, but it could also be the best place for opponents to discourage enrollment in the exchanges in order to collapse the system. \nFrom: _URL_0_\n\nDo we want socialized medicine? I would say the majority of us would. However, under the current method, it will be the most expensive socialized healthcare on the planet. There are other ways to fix this problem. This way just makes sure that doctors, hospitals, labs, and insurance companies get to keep goughing the poor via you tax dollar. Everyone should know by now that the figures on that hospital bill have nothing to do with reality.",
"Nothing is at stake because its congress. Nothing gets done anyways\n",
"Honestly just seems like a ridiculous act for attention ",
"THIS IS A POWER PLAY! \n\nPlease please please understand what Ted Cruz is doing here. \n\nThis is not meant to shift blame onto the democrats, this is a long-term, calculated effort by Ted Cruz and Mike Lee to \"purify\" the GOP, remove GOP Senate leadership, and shift the party consensus to the right. Everyone is of the understanding (whether true or not) that if the government is not funded, the blame will land on the GOP. This is meant to force the hand of Moderate Republicans to vote for a resolution that does not defund ACA. This way, these people will get oustered come the 2014 elections, as many of them come from states that have strong Tea Party support. The Tea Party is done with McCain types diluting their message, and want a unified front behind new GOP leadership. \n\nThe irony of all this is that most of what is happening is considered \"Astroturf\" (as opposed to grassroots). Made to look of the people, but actually sponsored by Heratige, American Century etc. \n\nSource: I live on Capitol Hill and am roommates with 2 GOP Senate staffers, RNC employee and a Dem. House staffer. Got the lowdown last night and actually went to the gallery to watch for an hour. ",
"It was a diarrhetic grandstanding in an attempt to join the upper-echelon of human spam. "
]
}
|
[] |
[] |
[
[],
[
"http://m.theatlantic.com/politics/archive/2013/09/the-double-absurdity-of-ted-cruzs-filibuster/279959/"
],
[],
[],
[],
[],
[],
[],
[
"http://tpr.org/post/how-texas-could-make-or-break-affordable-care-act",
"http://money.cnn.com/2013/07/01/news/economy/medicaid-expansion-states/index.html",
"https://en.wikipedia.org/wiki/Patient_Protection_and_Affordable_Care_Act#State_rejections_of_Medicaid_expansion"
],
[],
[],
[],
[]
] |
||
173tu2
|
If the universe is expanding at an accelerating rate, where exactly does that expansion happen? At the space between the atoms in my body, or somewhere else?
|
askscience
|
http://www.reddit.com/r/askscience/comments/173tu2/if_the_universe_is_expanding_at_an_accelerating/
|
{
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"text": [
"So we have two types of movement here. One is movement through space and the other is a stretching of the fabric of space itself. The common analogy is an ant on a rubber band. The ant walking on the band is traveling through space but stretching the band with an ant on either end will still result in them moving apart even if they are standing still on the surface.\n\nNow the molecules in your body are stuck together very strongly. As space stretches they will slide through space and stay stuck together. In fact even gravity between galaxies is strong enough to keep galaxies stuck together, but now the stretching of the material they are on is perceptible so on average we notice things moving a bit faster away from each other or slower towards each other.\n\nThe only place the stretching of space dominates so that objects on it are actually all moving away is at the super galactic cluster scale. These are the largest structures in the universe.\n\nedit: the bonus of why is two parts. The mechanism behind it is currently unknown. The fundamental reason behind it is that it is just the nature of the Universe we find ourselves in."
]
}
|
[] |
[] |
[
[]
] |
||
2msi1v
|
Why when welding metals are alloys other than the parent material used?
|
It's my understanding that a good weld material when joining metals would have properties similar to that of the parent metal.
If that's the case, why isn't the parent metal used to weld to itself?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2msi1v/why_when_welding_metals_are_alloys_other_than_the/
|
{
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"text": [
"You're confusing welding and brazing/soldering. With brazing or soldering a different material is used to join parts composed of another material. For example, you might use a tin based solder to make a physical and electrical connection between two contacts made out of copper. Welding is different, the primary action of welding is heat. In blacksmithing welding is done by taking two pieces of steel, heating them up to welding temperature, adding some flux to the welding area, and then hammering the pieces together, forming a weld.\n\nIn welding it's the heat that creates the join, not the material added. The addition of new metal in the process of welding is a side effect of the process and is merely a mechanism for the heat to penetrate into the join and cause those pieces to join together. Indeed, there are ways to weld that do not add additional material, such as friction stir welding or oxy-acetylene/MAPP welding without using filler. Also, if you weld two pieces together and then completely grind off the new material then you still can have a strong weld. The strength of the weld comes from the original material joining together due to heat, not from the added material.",
"Expanding on rocketsocks comment:\n\nDifferent metals are used in brazing and soldering so that the \"additional\" material melts before the metals being joined.\n\nFor example, when joining jewelry items made from from sterling silver you don't want to risk melting them. So, you use a solder which has a melting point from perhaps 50°F to 200°F below the melting point of the jewelry. The composition of the solder is chosen so that it combines with (disolves) the sterling silver when it melts and joins the items. The result is that you can apply the solder, heat the objects until the solder melts, and then let them cool. The result is that the joint has a slightly different composition than the rest of the item but you did not risk melting the objects that were joined. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
1ttadn
|
What psychological differences are there between adults and young adults?
|
I don't want to rely on stereotypes. Obviously some differences exist but separating the real from the imagined could be difficult so it seems safest to use actual studies.
|
askscience
|
http://www.reddit.com/r/askscience/comments/1ttadn/what_psychological_differences_are_there_between/
|
{
"a_id": [
"cebfnhq",
"cecfh6n"
],
"score": [
3,
3
],
"text": [
"The same question came up recently on a podcast I download, when discussing frontal lobe brain damage and development.The quick answer I found is from [here](_URL_0_). \n\n\"...the nerve cells that connect teenagers' frontal lobes with the rest of their brains are sluggish. Teenagers don't have as much of the fatty coating called myelin, or \"white matter,\" that adults have in this area.\"\n\nMaybe this is more a neurological explanation than you were looking for.",
"If by young adults you mean people generally in the age range of 16-25 and by adults over 25, it might be difficult to give a concise answer to your question. Some development in the brain structure might be still undergoing, but those differences probably aren't causing any effects that you can generalize over all young adults. Truth is, that people experience different things in their young adult lives and train themselves better or worse and for different kinds of tasks that might be relevant to their lives or not. As a result, they may mature quite differently, and other person might be a very mature and adult-behaving in 17 and other person still pretty childish at 30. Social contexts also wary, although generally young adults don't have many constricting components in their daily lives (no career, no family), which makes more opportunities available and thus maybe gives greater chance of personal growth on those years, which the individual may grab onto or then not."
]
}
|
[] |
[] |
[
[
"http://www.npr.org/templates/story/story.php?storyId=124119468"
],
[]
] |
|
2x45ah
|
Homework in American Schools?
|
Can anyone point me to an online source outlining homework in American schools, from the advent of them in the 1600s to today? That would be awesome. Thanks!
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2x45ah/homework_in_american_schools/
|
{
"a_id": [
"coxlds7"
],
"score": [
3
],
"text": [
"Well firstly I can point you in the direction for homework from the 19th Century.\n\n_URL_0_\n\nThe library of the uni of Pittsburg has digitised it's collection. This is a collection of schoolbooks from that period, it would include any homework given."
]
}
|
[] |
[] |
[
[
"http://digital.library.pitt.edu/cgi-bin/t/text/text-idx?;c=nietz;tpl=browse.tpl"
]
] |
|
7re6mp
|
what is a "flathead v8"?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7re6mp/eli5_what_is_a_flathead_v8/
|
{
"a_id": [
"dsw85gz"
],
"score": [
10
],
"text": [
"Flathead engines are ones where the valves are placed in the engine block, alongside the pistons. Compare to overhead valve engines, where it's up top.\n\nV8 means it has 8 pistons arranged in two sets of four, which meet at an acute angle, making a \"V\" shape."
]
}
|
[] |
[] |
[
[]
] |
||
3m6zmf
|
short selling
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3m6zmf/eli5_short_selling/
|
{
"a_id": [
"cvchx7r"
],
"score": [
2
],
"text": [
"Suppose I want to make a bit of money and you lend me your car to do so. I could sell the car to somebody for $120,000 (Nice car!) and in a few months buy it back from them. Since they have been using the car for a while it has done more kilometers/miles so I only pay $100,000. I still have to give the car back to you but have made an extra $20,000.\n\nShort selling is exactly this process but instead of a car you are dealing with shares in a company and they are borrowed from a broker. Short selling also only works if the value decreases. For example, what would happen if the person I sold your car to installed a brand new engine, wheels and wanted $150,000 for me to buy it back?"
]
}
|
[] |
[] |
[
[]
] |
||
8jf0gq
|
options and "buy to open," "buy to close," "sell to open," "sell to close."
|
I've watched several videos and had several people explain this to me and for some reason it is still really hard for me to grasp. Can someone explain to me what options are, what these four terms means, and how they all relate to each other?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8jf0gq/eli5_options_and_buy_to_open_buy_to_close_sell_to/
|
{
"a_id": [
"dyz6dbq"
],
"score": [
5
],
"text": [
"Options are a deal between two people, where one person pays the other for the opportunity to take an action later. Because they're a deal, we could create a brand new option from nothing (our agreement creates it) or we can trade our position in an already existing option. The exchange tracks all the options so that the final owners can follow through when the time comes for the agreement to end. \n\nBuying and selling to open means you want to create a new option. Buying to open means you'll pay money now to have the option to do something later. Selling to open means you'll get money now but be on the hook to fulfill the option's rules if the buyer wishes to do so in the future. \n\nBuying and selling to close means you're trading your portion of an already existing option to someone else. Buying to close means you were paid money to create an option, and now you're paying someone else to take your place for the remaining time. Selling to close means you were the payer previously and now you'll receive money from someone who want's to take your place as the person who can take the action for the remaining time. "
]
}
|
[] |
[] |
[
[]
] |
|
75e2mr
|
why dont they make a usb connected laptop charger?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/75e2mr/eli5_why_dont_they_make_a_usb_connected_laptop/
|
{
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"do5hb7b",
"do5hd6o",
"do5hdf6",
"do5hemp"
],
"score": [
3,
4,
2,
2
],
"text": [
"In the USB 1.0 and 2.0 specs, a standard downstream port is capable of delivering up to 500mA (0.5A); with USB 3.0, it moves up to 900mA (0.9A). The charging downstream and dedicated charging ports provide up to 1,500mA (1.5A).\n\nBasically, it would take a long time to charge.",
"They did, and they have. The primary reason usb wasn't used is because people are prone to killing their usb cables by constantly putting it in the wrong way, that's just the last thing you want from a cable. But, with the advent of USB-C quite a few laptops and monitors have been popping up that have a usb-c port which is just stellar because i can use my charger for my Nexus 6p\n\nThe laptop I'm currently using that has it is a chromebook acer 14 for work. ",
"The USB standard doesn't carry enough power to charge a laptop in a reasonable period of time. If you were OK with it taking three days to charge and not being able to run indefinitely even when plugged in you could, but most people prefer other solutions.",
"What do you mean? Like a laptop charger that charges the laptop through the USB port?\n\nBecause they make those now, but only for USB C\n\nPrior to USB C/3.1 you couldn't get enough power down a USB port to charge anything large, but USB Power Delivery supports large amounts of power, all the way up to 100 W with certain cables so you'll be seeing more USB C laptop chargers in the future. Many laptops are now just coming with one or two USB C ports which serve as both the data and charging ports"
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
4chqvv
|
is it true that vaping marijuana with vaporizers such as the volcano make weed completely safe for the lungs?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4chqvv/eli5_is_it_true_that_vaping_marijuana_with/
|
{
"a_id": [
"d1i9ymf",
"d1iawzs"
],
"score": [
14,
7
],
"text": [
"There is an insufficient amount of clinical data to answer this question with any level of confidence; vaping is a relatively new technology, and the negative effects of smoking are most prominent decades after first use. \n\nAnyone who answers this question with any more confidence than that is at best oversimplifying and at worst making stuff up. \n\nAs far as the potential effects...it may be better for you than smoking, but it also may be worse. There are certainly chemicals present in normally smoked marijuana that don't become airborne when vaping, which certainly suggests potential health benefits. However, it is also possible that the high temperature with normal smoking denatures potentially harmful inhalants, which remain intact during vaping and could have far-reaching health effects. We simply don't know right now. ",
"No one knows. \n\nBecause marijuana has been a schedule I narcotic, it hard to do *any* testing on it.\n\nBecause vaping is so new, we have little data on its long term effects.\n\nAnyone who says vaping marijuana is completely safe is an idiot. Not because they are necessary wrong, but because they have no one of knowing and are just talking out of their ass."
]
}
|
[] |
[] |
[
[],
[]
] |
||
7rlx3o
|
is the concept of light speed defined by light itself, or does light just want to go infinitely fast but physics puts a cap on it?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7rlx3o/eli5_is_the_concept_of_light_speed_defined_by/
|
{
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3
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"text": [
"Light is fast, way faster than most people can even imagine, but thankfully our measurements are very precise as well, so we are able to measure it very accurately (First done by Fizeau and Focault in 1830ish, not like /u/ganganinja claims by sending lasers to the moon, we do that to measure how far the moon is away, knowing how fast light is and then measuring the time).\n\nLight, sadly, is not infinitely fast, it is actually very, very, very slow compared to the size of the universe, even the closese star is lightyears away form us, meaning that the light you see when looking up at the sky and seeing all those small little bright spots has taken millenia (and often way, way, way, way, way, and i mean like way way way, longer than just a few millenia, wich is basically no time, to be honest), to get from the star that emitted it to us here on earth. \n\nI would also like to add that in fact these days we dont measure the speed of light at all, in the 1980s we just agreed on the speed of light as a certain number (exactly 299,792,458 metres per second) and are now using that number as the basic measurement for everything (so if you know how long a metre is you no longer go to baris and look at that stick napoleon made and about wich he said \"this is a metre, and any metre on earth is defined by beeing exactly as long as this stick\", you instead take the distance for wich a beam of light needs exactly 1/299,792,458 seconds to travel it)",
"As far as we know, it's the second one. Particles with no mass travel as fast as physics allows anything to travel. Since photons are the massless particles that we encounter most often, we first encountered that maximum speed by observing light and we called that speed \"the speed of light\". ",
"Watering it down, a lot, light is a wibble in the em field. \n\nSound moves at different speeds through air, or helium, or steel essentially because of atoms knocking into each other. So basically energy take time to transfer through the material. Even light! Because its just a wibble in the EM field. If you were to shine a light next to a steel beam while passing electric current through the beam, the light would arrive *just* ahead of the electric current. The energy took longer to travel through steel than free space.\n\nSuppose you wanted to travel faster than sound, what happens? You move faster through the air than the air can transfer the energy of the sound you make. It stacks up and you get a boom, all the sound at once.\n\nWhat happens when you toss a light speed particle at steel(which it should travel slower through, electric current is a wibble in the EM field too), what happens? Well, again really watered down, the energy stacks up and you the excess energy gets released as [Cherenkov radiation](\n_URL_0_). A light boom!\n\nOk so TLDR whats this all mean?\n\nLight can travel slower through a material. But in free space, a vacuum, it travels as fast as energy can be transferred through the EM field.\n\nYou can't travel faster than C because youd outrun the fields holding you together.\n"
]
}
|
[] |
[] |
[
[],
[],
[
"https://en.m.wikipedia.org/wiki/Cherenkov_radiation"
]
] |
||
3a3rkn
|
why don't networks like espn put their field reporters on a split second tape delay to remove the awkward pauses between a question and answer?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3a3rkn/eli5_why_dont_networks_like_espn_put_their_field/
|
{
"a_id": [
"cs9101r"
],
"score": [
3
],
"text": [
"Because, if they did, there would be the same awkward pause between the field reporter's response and the next question.\n\nThe only way around it is to edit the pauses out before putting the segment to air. But you can't do that live."
]
}
|
[] |
[] |
[
[]
] |
||
1xuqyg
|
Did people during the 1700s ever try to imagine life in the year 1800s?
|
You know how people in the 1950s try to imagine life in 2000. Was there anyone back then who ever thought in 1700 what 1800 or 1900 would look like?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1xuqyg/did_people_during_the_1700s_ever_try_to_imagine/
|
{
"a_id": [
"cfhwg4g"
],
"score": [
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"text": [
"Hi there! Sorry it took me a few days to answer you. I needed to dig up a bunch of old notes to refresh my memory.\n\nSo yes, 18th century social theorists had a strong sense of futurism. In a broad sense an intellectual concern with the future had existed since the Renaissance rediscovery of Europe’s Classical heritage, which provided the West with a new sense of time’s passage that inevitably looked to the future as well as the past. Coupled with the Protestant Reformation and the Scientific Revolution, by the time the 18th century came around there was an understanding that time was not only changing, but malleable, and that humans could influence events and make their future better.\n\nThis really comes across in Enlightenment intellectual discourse, which emphasizes science, reason, toleration, and education as the means by which to establish a better future. During the 18th century there is a very self-conscious movement amongst social elites (noble or otherwise) to put these ideas into practice in order to become more culturally “enlightened” than their neighbours. It’s from this that we get the phenomenon of [enlightened despotism]( _URL_2_). For example, King Fredrick II of Prussia and the Russian Empress Catherine II both conducted extended personal correspondences with the French thinker Voltaire, taking input from him in how to govern their countries in a way that aligned with humanists ideals. \n\nWhile the effectiveness of their policies are a subject of debate, there’s no question that this sort of intellectual and political atmosphere led to plenty of speculation about what the future held. What follows are couple key people from the century whose work dealt implicitly with questions of the future. I’m afraid I’m not a real expert on any of these individuals but you can certainly take a quick look at what they contributed to discussions of the future and possibly read more into those that interest you!\n\n[Giambattista Vico](_URL_0_) (1668-1744): Here’s a man who this subreddit owes a lot to. He argued that the study of history was just as important as the study of human nature, as any account of human achievement is necessarily a historical account. Context is key to the understanding of history as human values and concerns are always evolving. He paved the way for Hegel and Marx to argue for the close interrelationship of all aspects of society, with politics, economics, and art all depending on one another as history moves forward.\n\n[Montesquieu]( _URL_5_) (1689-1755): Applied the scientific idea of causation to history. A good quote that puts this in perspective is: *“If a particular cause, like the accidental result of a battle, has ruined a state, there was a general cause which made the downfall of this state ensue from a single battle.”* His *Spirit of Laws* published in 1748 was a monumental attempt to compare different human societies and institutions, it was a sort of political anthropology that can be seen as the predecessor of modern cultural and social anthropology. He categorized different government types and analyzed government functions, concluding with a strong argument for the need of checks and balances for future governments.\n\n[Nicolas de Condorcet](_URL_3_) (1743-1794): Set out to describe human history in terms of the progress of science, explicitly relating it to progress in areas such as human rights by suggesting a Newtonian law of causality between science and humanism. The growth of knowledge in the natural and social sciences would lead to justice, freedom, prosperity, and moral improvement and history is patterned upon the progressive development of human capabilities. Social evils arise from ignorance and error, not from human nature. Condorcet was extremely influential and helped to make the idea of “progress” a central concern of European civilization throughout the 19th century.\n\n[Lousi Sebastian Mercier](_URL_1_) (1740-1814): This might be a little more what you were thinking of in when you originally asked this question, as he published a book called *The Year 2440* which described a utopian Paris. He intended for the book to be both a scathing criticism of Revolutionary Paris and simultaneously a “guide book for the future”.\n\n[Jonathan swift](_URL_7_) (1667-1745): Another writer who used ideas of exploring strange lands and distant futures to satirize European society. One of his utopian depictions described a society of researchers governed by reason, which is pretty much the goal of promoters of the enlightenment like Voltaire.\n\n[Mary Wollstonecraft] (_URL_6_) (1759-1797): Wollstonecraft was an early feminist who published the incredible *Vindication on the Rights of Women* in 1792 that was deeply concerned with the place of women in society and the need to alter social norms in order to conform to Enlightenment ideals of education and reason.\n\nSomething that I’m sure you’ve noticed about all of these examples is that thinking about the future was **serious business** by 18th century intellectual standards, and there is a lack of the more frivolous futurism seen in the science fiction genre that started with Jules Verne in the 19th century. I’d suggest this is the result of two things:\n\n * Firstly the very direct application of contemporary intellectualism to governance. Obviously this constantly happens within many societies indirectly, but during this period everyone saw a very blatent connection between social philosophy and governmental policy that led to a number of large-scale changes and helped to ferment the French Revolution, as well as establish modern political discourse. \n\n * Secondly, there is long history of utopianism within European literature and philosophy stretching back to ancient Greece that often evoked the future to criticize the present and advocate particular courses of action to ensure this utopian ideal. For a really good collection that contains a great cross-section of Utopian short stories from throughout history I strongly recommend Gregory Claeys [The Utopian Reader]( _URL_4_). Looking over some of the texts in there will really help you understand where these 18th century thinkers were coming from.\n"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Giambattista_Vico",
"http://en.wikipedia.org/wiki/Louis_Sebastien_Mercier",
"http://en.wikipedia.org/wiki/Enlightened_absolutism",
"http://en.wikipedia.org/wiki/Marquis_de_Condorcet",
"http://www.amazon.com/The-Utopia-Reader-Gregory-Claeys/dp/0814715710/ref=sr_1_1?ie=UTF8&qid=1392683569&sr=8-1&keywords=the+utopian+reader",
"http://en.wikipedia.org/wiki/Charles-Louis_de_Secondat",
"http://en.wikipedia.org/wiki/Mary_Wollstonecraft",
"http://en.wikipedia.org/wiki/Jonathan_swift"
]
] |
|
138e50
|
Is this company, StemCell100, a scam? Is there any evidence that this product does what it says it does? What exactly makes it a scam or not?
|
_URL_0_
It would be cool if this was legitimate, but I have serious doubts. Considering it's not that popular at all. At least from what I have seen.
|
askscience
|
http://www.reddit.com/r/askscience/comments/138e50/is_this_company_stemcell100_a_scam_is_there_any/
|
{
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"text": [
"* Seems to fix a large variety of symptoms, basically general aging symptoms and I don't look/feel great\n* Not FDA reviewed\n* Throws out a lot of scientific words and goes into long winded explanations about how this makes you younger/healthier on the front page of the website \n\nThis seems to really be a pill that has a lot of health supplements that has been re-branded as a stem cell support. So it is plausible that there could be some health benefits gain from this, although I am going to leave a real analysis of that up to a nutritionist.\n\nTheir fly studies seem dodgy, the study was done by the company itself and their is no actual paper of the study, just some plots and then more talking about the benefits of all the herbs involved.\n\nI high doubt this is some wonderful stem cell aiding medicine, jut an herbal supplement",
"Complete and utter scam.\n\nThere are zero stem cells in this product. Even if their were, those stem cells would make you **SICK**, not better. \n\nIn order for stem cell therapy to work, they must be **YOUR** stem cells. Otherwise they would be recognized as foreign to your body cause an immunorejection reaction making you sick. ",
"After looking at their 'longevity research' page, I'm throwing my vote in for scam. They do a little *Drosophila* study (of which I am also highly dubious, but okay) but nowhere on that page do they **show** that their product has any effect on stem cells. They mention that *Astragalus membranaceus* inhibits mTOR and thus causes the animals to defy aging, but it's almost laughable to think that the solution to aging could possibly be so easy. *Plenty* of experiments have been done with mTOR and no spectacular results like this have been found.\n\nI'm not entirely ready to discredit the molecular activities of compounds found in traditional herbal remedies, as it's entirely possible that they do truly have some kind of effect. But to claim that they mixed up some herbs and it makes your adult stem cells live much longer and healthier? Utter fantasy.\n\nedit: Not a single reference on their 'stem cells' page. As a nascent *Drosophila* stem cell researcher, I am even more highly skeptical than before."
]
}
|
[] |
[
"http://www.stemcell100.com/"
] |
[
[],
[],
[]
] |
|
2iy5t7
|
How does the water-vapour runaway greenhouse effect work?
|
Hello Science!
I'm trying to understand how the water-vapour runaway greenhouse effect works.
If the planet had no atmosphere then the total light energy from the sun (S) would balance the black body radiation from the earth. Now by [Stefan-Boltzmann law](_URL_0_) this is proportional to the 4th power of temperature. So ignoring all constants.
S = T^4.
Now if you add a layer of atmosphere to the planet (which has greenhouse gasses in it) then some proportion of the emitted radiation is caught by the gasses and trapped on the planet. Here is a [nice picture.](_URL_1_)
So what we get is some constant in front of the radiation (C) which represents the proportion of the radiation that escapes into space. And we get
S = C*T^4
and the overall temperature of the planet is higher because (0 < C < 1). Now in the case of water vapour when the planet gets hotter the amount of water vapour in the atmosphere increases (C depends on T). This amount of water vapour must be between 0 and (all the water in the world is gas around the planet).
It is hypothesized that on Venus a runaway effect took place where as the planet got hotter more and more water vapour entered the atmosphere and this made it hotter and now it is very hot.
The system will eventually come to an equilibrium as when (all the water in the world is gas around the planet) some radiation will still escape and so the system will balance (C > 0). (If no radiation escapes (C = 0) then the temperature will increase to infinity!).
What I want to know is three things.
I. How does the constant C depend on T when it comes to water vapour? Presumably this relationship is complicated because it takes a lot of energy to evaporate and ocean (you can't just say "today T = 101 degrees C" and have all the oceans in the world evaporate instantly). So it must be some kind of delay equation proportional to the specific heat capacity of water and the volume of the oceans. Is this right? What is the relationship?
II. What stops this process? Presumably once there is enough water vapour in the environment it gets hotter and that makes more water vapour. If the gradient of C as a function of T is negative everywhere (meaning as you increase the temperature there is more water vapour and so less radiation escapes) surely this implies once the process has started it is inevitable.
III. Is this differential equation for describing temperature as a function of time correct?
dT/dt = S - C(T)*T^4
Thank you very much for your help with this :)
|
askscience
|
http://www.reddit.com/r/askscience/comments/2iy5t7/how_does_the_watervapour_runaway_greenhouse/
|
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],
"text": [
"So the C in your...\n\nS = C*T^4\n\n...takes the role of emissivity. It's fine for zeroth-order back-of-the-envelope calculations, but really doesn't work too well for getting good numerical answers when examining the greenhouse effect.\n\nThere are two problems here:\n\n- The Stefan-Boltzmann Law is a gray calculation - you integrate all wavelengths together and come up with an average emission. \n\n- It assumes a single layer that has only a single temperature that describes the entire atmosphere.\n\nUnfortunately, radiative transfer isn't this simple. The absorption spectrum of water vapor is very complex, which means that you'll get very different emissivity depending at what wavelength you're probing.\n\nFor example, in the middle of a water vapor absorption line, the opacity is very high. That means the planetary cooling that's occurring in that wavelength will come from quite a high location in the atmosphere, since that's the only height at which photons can escape directly to space. Between emission lines, though, opacity is low, so those wavelengths will emit to space from a lower \nheight in the atmosphere.\n\nThat wouldn't be such a problem if the atmosphere were isothermal - i.e. the same temperature everywhere - but it's not. Up until you get to ~10 km high, the temperature is decreasing. This means wavelengths that are high opacity (and thus emitting from higher in the atmosphere) are also emitting less because of that T^4 term.\n\nSo not only is the C wavelength-dependent based on the water spectrum, but since that's also going to determine which height in the atmosphere is cooling to space, it also means the T is wavelength-dependent, too. Add to that the feedback cycle - increased water vapor not only changes the temperature throughout the atmosphere, but also changes opacity and thus the location of emission to space - you've suddenly got a very difficult non-linear problem.\n\nWhen you end up doing a full calculation over all wavelengths and also include cloud feedback cycles, you find that the runaway greenhouse effect kicks in [somewhere around the global average surface temperature reaching 50 C (120 F)](_URL_0_)...though the exact value of this is still debated. With the global average still somewhere around 15 C (60 F), we're still a long way away from that.\n\n**TL;DR**: Your functional form is really too simple to answer this question properly."
]
}
|
[] |
[
"http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law",
"http://geographyslc.files.wordpress.com/2014/02/greenhouse-effect.jpg"
] |
[
[
"http://arxiv.org/abs/1312.3337"
]
] |
|
d90v9v
|
How did Spain transition from fascist dictatorship to its current democratic, constitutional monarchy? Is it true that Franco bequeathed the country to King Juan-Carlos and it was he that instituted democracy?
|
I have heard the above narrative from local people while traveling in Galicia, Spain. From that telling, it sounds like Juan-Carlos I defied expectations and imposed democracy from the top down. Did he really have the option to assume Franco-style dictatorial powers, or was he bending to some popular demand for change?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/d90v9v/how_did_spain_transition_from_fascist/
|
{
"a_id": [
"f1e7p57",
"f1f5yrt"
],
"score": [
163,
34
],
"text": [
"Modern Spanish history is one of the most interesting topics I have found. Anyway, onto an answer:\n\nFranco approved a law of succession in 1947, saying that Spain was kingdom and would remain a kingdom. Of course, Spain would have no king while Franco was alive as he was acting head of state. The law also said he could name his successor when he chose to. \n\nDon Juan, the heir to the Spanish monarchy, and Franco decided in 1948 that Don Juan’s son - Juan Carlos - would return to Spain to be educated in Spanish schools and in Franco’s ideology. In essence, Franco groomed Juan Carlos to be his heir. \n\nJuan Carlos completes this education and eventually married Sofia. And in 1969, Franco named him as his rightful successor to the dictatorship and Juan Carlos had to swear loyalty to Franco’s Movimiento Nacional. The two worked together after this, with Franco guiding Juan Carlos in his new role. \n\nFranco dies in 1975 and Two days later, Juan Carlos becomes king of Spain. Now, Spain enters the period of the Restoration of the Monarchy. Juan Carlos started to issue reforms to the government and appointed Adolfo Suarez as president/prime minister (depends on your translation and understanding of Spanish government). Suarez would become instrumental in the transition to democracy and would become the first democratically elected prime minister of Spain’s new government. \n\nIn this time, many changes occur but one of the most interesting is el Pacto de olvido (the pact of forgetting), which was a political decision by both the left and right parties to essentially forget everything that happened during the Civil War and under Franco. This pact ensured that there would be no prosecutions for persons responsible for mass suffering. Important questions about the recent past were entirely ignored, so that Spain and its politicians could look towards the future and make the reforms needed. \n\nIn June of 1977, Spain held its first elections and in 1978, a new constitution was drafted that acknowledge Juan Carlos as king. \n\nSo, to answer your question: Franco did “bequeath” the country to Juan Carlos, but only after he had been groomed in his education and sworn allegiance to Franco and his ideologies. Juan Carlos did help ensure that Spain would become democratic but most of the “work” was completed by Suarez and other politicians of the time. \n\nSome attribute these happenings as to why Spain has largely avoided the populist movements that we see in many countries today. Spanish people still struggle with The Pact of Forgetting and it’s implications to today, like should Franco’s remains be removed from El Valle de los Caídos (The Valley of the Fallen).",
" > Did he really have the option to assume Franco-style dictatorial powers, or was he bending to some popular demand for change?\n\nThis is a very interesting question, and I'll try to answer to it, complementing /u/NearbyConcept answer.\n\nNow, the short answer to both parts of the question is yes. The long answer, well, get ready because I got some long paragraphs for you detailing the social and political climate Juan Carlos found when he got in the throne in 1975.\n\nJuan Carlos had the power granted to him as Head of State by the **Organic Law of the State of 1966**, one of the Fundamental Laws of the Kingdom, which worked as a de facto Constitution for the Francoist Regime. This gave him the power to appoint the Prime Minister, to appoint one third of the members of the Cortes (a pseudo-parliament which enacted the Laws), the supreme command of the military, and the soft power which went with being the King. In this regard, he had the same legal powers as Franco. Now, what he didn't have was the strong base that Franco had during his 39 years in power to continue with an authoritarian regime. Because the legs that supported Francoism (i.e. the Catholic Church, the military, the fascists and the conservatives) had all lost the strength they had during the 1940s, thanks both to social changes and the opening of the Regime during the 1960s and 1970s, which occurred to face this social changes.\n\nIn 1940-50s the economy was in shambles, and Spain was living in economic isolation from the rest of the world. In 1957 the State was on the verge of bankruptcy, so Franco removed the Fascist government in place and put in charge what is known as the \"technocrats\", conservative men from Opus Dei that nonetheless disliked economic autarchy and wanted to liberalise the economy. This, together with the international recognition and acceptance of the Regime, after the agreements with the Vatican and the USA in 1953, allowed Spain to be open to foreign capital, which created what is called the \"**economic miracle**\" of the 1960s. Thanks to tourism and foreign inestment, the economy boomed. This accelerated the rural exodus (in 1950s Spain for the fist time had more urban than rural population), created a baby boom (in Spain, it was during the 1960s), and reduced the mortality, which created a major social shift. More population in the cities, more young people, more industrial workers (in 1970s, they were 75% of the workforce), more educated people (in 1970, alphabetisation reached for the first time 90%), progressive liberalisation of the women, mass media, etc. all of this factors undermined the traditional support of the Francoist State. They also allowed the mass population to gain economic dignity and, through the openness with the outside world, demand the political regimes that were established in Western Europe.\n\nIt was in response to those demands that the technocrats implemented some minor political reforms. They created a Social Security in 1963, and promulgated the **Law of Press of 1966**, which relaxed the limitations on censorship and eliminated preventive censorship, shifting its burden from the State to the Publishers. The **Law on Religious Freedom of 1967** ended the religious monopoly of the Catholic Church. They also started to allow some minor cultural expressions in minority languages, like songs and books, and extracurricular teaching of the languages, even allowing from 1964 the broadcasting of a TV show in Catalan language (in the only TV channel from the times, TVE).\n\nThis changes were not enough though, and the population started pushing for political reform. During these times grew major popular opposition to the regime. The workers movements and labour conflicts, which started in 1962 with the Miner’s strike in Asturias, pushed for the creation of illegal clandestine trade unions known as “workers commissions” to negotiate with their bosses without the intervention of the only legal union, known as the “Vertical Trade Union” (because it included both workers and company owners). These commissions would later become the trade union **Comisiones Obreras** (CCOO), still the largest in Spain, which was later joined by the older unions UGT, CNT and others. We shouldn't forget the growing dissent on the new neighbourhoods, created to accommodate the massive internal immigration to the industrial cities, to protest for the lack of public services in the area, sometimes even roads were missing.\n\nThere was also opposition coming from the intellectuals, specially from the Universities, now with a much bigger number of students which opposed the regime on ideological grounds (as usually intellectuals do). Another major point of opposition was the Catholic Church itself, specially from the middle and lower ranks, who felt emboldened by the liberalist reforms of the Second Vatican Council and opposed a repressive regime which went contrary to the christian values, despite its official backing of the Church. Finally, the opposition from national minorities, specially from the major industrial centres of Basque Country and Catalonia, gain a lot of support all across the class spectrum. In Catalonia, the upper and middle classes pushed for the normalisation of their culture and national symbols. In the Basque Country, this \"bourgeois\" opposition was joined by nationalist marxist-leninist terrorism, embodied in the organisation **ETA** (Basque Land and Freedom). Many other terrorist groups were created during the mid 1970s, like GRAPO, FRAP, Terra Lliure, FAG, LAR; and even some ultra-right groups, like BVE, ATE, Triple A, GAE or Guerrilleros de Cristo Rey. \n\nTo face this opposition, the technocrats wanted to increase the legitimacy of State, so they made the regime to stand on more firm legal grounds pushing for the Organic Law of the State. They also increased the repressive apparatus of the State by creating the **Court of Public Order** in 1963, which would be in charge of judging political crimes. The Political-Social Brigade (the secret police), the Civil Guard and the Armed Police (urban police) reaffirmed their role as executing forces of the Regime by beating demonstrators, torturing detainees and executing or imprisoning those in the opposition.\n\nAt the same time, the Francoist apparatus was divided into two main factions. On the right there were the “**immobilists**”, whose radical right-wing was known as the “**bunker**”, mainly formed by the most senior members of the National Movement (Franco’s “political party”, the only legal one). Their main figure was **Admiral Luis Carrero Blanco**, Franco’s right hand man and veteran of the Civil War. On the right there were the “aperturists” or “**reformists**”, whose main figures were **Manuel Fraga Iribarne** (technocrat Minister of Tourism), **Torcuato Fernández Miranda** (Secretary of the Movement and professor of Political Law of King Juan Carlos) and the young **Adolfo Suárez** (director of the public tv and radio RTVE)."
]
}
|
[] |
[] |
[
[],
[]
] |
|
1qp2p0
|
Will oil and water mix in a vacuum?
|
In a normal space,oil and water don't mix,so would they in a vacuum??
|
askscience
|
http://www.reddit.com/r/askscience/comments/1qp2p0/will_oil_and_water_mix_in_a_vacuum/
|
{
"a_id": [
"cdf1gxn",
"cdfcaoi"
],
"score": [
17,
2
],
"text": [
"Their aversion to forming a miscible solution is due to differences in intermolecular forces and the entropy of the molecules at the interface, not gravity.",
"Gases always mix; liquids sometimes mix. In liquids, intermolecular forces are strong enough to control mixing. In a gas, they aren't. If you took normal oil and normal water and put them under vacuum, they would both boil. The liquid phases would not mix (except for on a large scale, due to agitation by the boiling), while the gas phases would mix.\n\nBy a large scale, I mean things like emulsions: bubbles of oil in water, or vice-versa. This is not stable for liquids that really don't want to mix, but can form temporarily, and on a large scale. We'll ignore emulsifiers."
]
}
|
[] |
[] |
[
[],
[]
] |
|
239g0n
|
Did 'No-go' areas that were controlled by the IRA in Northern Ireland show any fluctuations in crime levels?
|
We're doing the troubles in Northern Ireland in school at the moment and it mentions areas like 'Free Derry' where the RUC and army wouldn't enter and the IRA controlled them. Was there an increase or decrease in crime and how was the IRA's way of dealing with crime perceived by the people who lived in these areas?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/239g0n/did_nogo_areas_that_were_controlled_by_the_ira_in/
|
{
"a_id": [
"cgv177y"
],
"score": [
4
],
"text": [
"Why were there free areas where the RUC and British Army wouldn't enter?"
]
}
|
[] |
[] |
[
[]
] |
|
8ga2in
|
why is the war on drugs inherently flawed but a war on guns wouldn't be?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8ga2in/eli5_why_is_the_war_on_drugs_inherently_flawed/
|
{
"a_id": [
"dy9yzas"
],
"score": [
2
],
"text": [
"That's an awfully broad question. There are a variety of tactics and solutions that can take place under either umbrella term, which can be good or bad. Beyond that, the abuse patterns in either are certainly not the same. "
]
}
|
[] |
[] |
[
[]
] |
||
458cdy
|
how are non latin alphabet characters typed on a phone?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/458cdy/eli5_how_are_non_latin_alphabet_characters_typed/
|
{
"a_id": [
"czvwiwi",
"czvwj2y"
],
"score": [
3,
2
],
"text": [
"What kind of keyboard are you talking about? Just like QWERTY keyboard, there are keyboard for plenty of non-Latin alphabets, as shown here: _URL_0_\n\nEvery keyboard software supports installing various keyboard layouts.\n\nEast Asian languages also have special keyboard, [as explained in each of the answers here](_URL_1_).",
"You can switch your keyboard layout on most phones. Same as desktop keyboard layouts can be changed. For example, I can simply swipe my spacebar and say привет, swipe it back and continue in English."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Keyboard_layout",
"https://www.reddit.com/r/explainlikeimfive/search?q=chinese+keyboard&restrict_sr=on&sort=relevance&t=all"
],
[]
] |
||
51v9ug
|
why is the fine art trade a medium for money laundering?
|
It seems an illiquid asset and very subjective in value.
Billions of dollars worth of funds were embezzled from a Malaysian government fund in what's being called the "1MDB" scandal. The WSJ reported that money was diverted into real estate, and also the purchasing of a Van Gogh piece. Fine art purchases with ill-gotten money is method of concealment I've heard before.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/51v9ug/eli5_why_is_the_fine_art_trade_a_medium_for_money/
|
{
"a_id": [
"d7f6x8o",
"d7f78pq"
],
"score": [
2,
7
],
"text": [
"It's not just fine art - almost anything with intrinsic, lasting value is fair game for the criminals. Basically it's very difficult to give somebody a large sum of money without questions being asked but 'gifting' somebody a Van Gogh may be unusual but it isn't illegal. In doing that, the new owner has no burden of responsibility to explain where the money came from to buy it in the first place.",
"The value of fine art is pretty well pure perception. If i say this shitty painting is worth a million dollars and you're willing to cough up a million dollars for it, that's its value. This makes it a very easy way to disguise money laundering (which is just processing illicit income through legal transactions in order to provide a legal source to claim that income). You can also produce as much art as you like, and thus move quite a bit of money. Plus the fine art trade in general is a fairly secretive one with little oversight; you can have transactions where the buyer and seller are both listed a \"private collection\" or something similar. Neatly ties up any paper trail, especily if it was a cash transaction \n\nIt's also really easy to transport and smuggle art. If I have a box that says it's a shitty 50 dollar painting, but it's actually worth millions legitimately...how the fuck does customs know? They can't have someone show up and appraise every stupid painting so unless something else tips them off, across the border it goes with no one the wiser. And then maybe it disappears for 5-6 years, sitting in some rich person warehouse. Or it sits a freeport somewhere in singapore or something where it changes hands anonymously half a dozen times over a decade and good luck tracking any of that backwards when it finally sees the light of day again. \n\n\n\n\n"
]
}
|
[] |
[] |
[
[],
[]
] |
|
1t67jj
|
how the us stock market is not currently experiencing a bubble/overbought?
|
Given the state of the US economy - 7.3% unemployment with the real unemployment rate (U-6) closer to 13%, GDP growth sluggish at 2%, - how come the US stock market is hitting new heights? My understanding is that this can't reflect the real economy and must be a bubble waiting to pop.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1t67jj/eli5_how_the_us_stock_market_is_not_currently/
|
{
"a_id": [
"ce4pyyq"
],
"score": [
2
],
"text": [
"_URL_0_\n\nThe answer remains mostly the same - the economy, while a factor in the stock market, is not so large a factor that it defines how the stock market will perform. Plus things like unemployment and GDP growth are not the only pieces of the economic puzzle - there is a lot more to it than just statistics.\n\nThere are sectors in the US Stock Market that are not doing well - similarly, there are sectors in the US Stock Market that are doing very well. There are some sectors might be bubbles fueled more by demand/popularity rather than real value, and some that are generally just doing well. \n\nThe entire 'market' is not one giant bubble - rather than thinking of the stock market as a massive entity in and of itself, imagine it as a bunch of pools of water. Some pools might shrink in size, other pools might grow. Overall, there is growth, because there are always going to be pools that find a way to grow even if overall conditions are shit.\n\nTL;DR: The US Economy is not so large a factor that its decline would necessarily be reflected in the stock market. There are many parts of the stock market, and there are almost always areas where people find a way to profit in bad times. The market will follow those leaders, and the stock market will find a way to keep growing."
]
}
|
[] |
[] |
[
[
"http://www.reddit.com/r/explainlikeimfive/search?q=stock+market+high&restrict_sr=on&sort=relevance&t=all"
]
] |
|
9bt0rm
|
how do people die from too much plastic surgery?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9bt0rm/eli5_how_do_people_die_from_too_much_plastic/
|
{
"a_id": [
"e55giiv",
"e55gqtk"
],
"score": [
4,
3
],
"text": [
"There's risks involved with any surgery, especially when anesthesia is involved. Things can go wrong - the person's heart stops, doctor makes a mistake, person gets an infection, etc. The odds of this for cosmetic surgery are low but if you keep going under the knife you're taking that chance each time and one day may get unlucky.",
"Surgery carries inherent risks of infection and anesthesia mistakes. These are greater for longer and more invasive procedures, but also present for seemingly minor operations.\n\nThose risks are magnified when you're getting budget surgery done in a van in Guatemala because no reputable surgeon would agree to mutilate you for $500.\n\nAnd of course, people who undergo dozens of superfluous operations because they hate themselves tend to have other substance abuse issues."
]
}
|
[] |
[] |
[
[],
[]
] |
||
5kd874
|
us drug adverts seem to mostly contain a voice over of the negative side effects so what is the point in having them?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5kd874/eli5us_drug_adverts_seem_to_mostly_contain_a/
|
{
"a_id": [
"dbn37vg"
],
"score": [
2
],
"text": [
"Interest-only, in many countries, search advertisements are illegal. Most other developed Nations don't allow drug companies to directly Market their concoctions to Consumers. Part of it is because of the things you've noticed, which is that most consumers basically ignore the side effects at the end and instead pester their Physicians about whatever strange new drug we saw on television. This is likely a factor in the fact that so many Americans are on medications, with the various complications that come with that fact. Those warnings at the end are supposed to be there to protect the consumer, but that's not how they work. If McDonald's had a voice at the end of every commercial saying that their food contributes to obesity and heart disease, people would still ignore that morning had to go buy a Big Mac because they saw it on TV. That's how marketing works."
]
}
|
[] |
[] |
[
[]
] |
||
1vwvqu
|
There's a common condition colloquially known as "hypoglycemia," which doesn't actually meet the medical definition of hypoglycemia. What is it really?
|
There are lots of people who suffer a very specific set of symptoms after a given interval of time from the last meal. Typically: irritability, extreme fatigue, shakiness, dizziness, inability to concentrate, loss of muscle strength, etc. Most people who have this problem describe it as "hypoglycemia." But true hypoglycemia has other symptoms, such as seizures, which aren't included. So what is actually going on? Is there any research on this condition? Is there a name for it?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1vwvqu/theres_a_common_condition_colloquially_known_as/
|
{
"a_id": [
"cewufx6"
],
"score": [
4
],
"text": [
"There is in fact a name for this: [idiopathic postprandial syndrome](_URL_0_. The syndrome was first described in the 1980s to distinguish between patients with true hypoglycaemia and those suffering only the symptoms you describe. The word \"idiopathic\" means \"of unknown cause\", so I can't give you an answer as to what causes the symptoms. \n\nAs far as I'm aware, there isn't any real research going on into it; it's not exactly a serious pathology, and there's no obvious profit for companies in finding out what's going on and curing it."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Hypoglycemia_(common_usage)"
]
] |
|
8pecp2
|
energy changes and transforms, but doesn't disappear.
|
I understand what that means, but I've been thinking about it.
Imagine I'm sawing a log. The energy I got through food transfers to the hand saw, which in turn saws the log. I'm OK thus far, but what happens with that energy after that? Theoretically there's a finite amount of energy in the universe, so where does that energy goes after sawing the log? How does it go back the the "energy pool"?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8pecp2/eli5_energy_changes_and_transforms_but_doesnt/
|
{
"a_id": [
"e0akdn8",
"e0akezo"
],
"score": [
7,
3
],
"text": [
"The saw and the log both heat up, so the chemically energy from your body is turned into thermal energy in the log and saw. Also, the sawing makes a sound, so some energy is lost to sound. \n\nEdit:\nI also want to talk about the “energy pool” idea. Certain energy transformations are basically non-recoverable. A good example (for the most part) is the heating of the saw and log. It’s very difficult to recover that energy in a usable form. There will always be some amount of energy that is no longer usable. This is embedded in the idea of entropy always increasing. \n\nEntropy in this case (this is my preferred method of talking about entropy) is basically the ratio between total energy and usable energy. Since there’s always energy that is made unusable in a system, this ratio has a tendency to increase (usable energy goes down and total energy is constant, so that fraction gets larger). This is the 2nd law of thermodynamics. ",
"Almost always if you're asking \"where did the energy go\" the answer is \"heat\".\n\nYour body converts chemical energy into kinetic (plus heat) which transfers from your body to the saw. Most of that energy gets turned into heat through friction between the saw and the wood.\n\nIf you think about the effort it takes to use a saw, most of that effort is the saw *rubbing* against the wood. What happens when you rub something? It generates heat! And you can feel this if you touch the blade of a saw after using it - it'll be hot."
]
}
|
[] |
[] |
[
[],
[]
] |
|
92vqgw
|
At the beginning of the 20th century, before refrigerators were commonplace houshold appliances, how did people conserve their food? Did they still use lots of salt and store it in the basement or was there some sort of interrim period where an alternative solution was found?
|
This question may seem a little random but I'm currently stuck at a hotel with no kitchen or refrigerator so I have to live off fruits, vegetables and bread. This made me wonder how people used to deal with not having a refrigerator before they were common household appliances. Did people just not eat meat? Did they all go to taverns for meals because those places had refrigerators or at least basements and a lot of salt? If meat was stored salted in basements, how did poor people deal with their food situation? Was starvation still common in early 20th century europe? I hope there's someone in this subreddit who can answer my peculiar question. You have to know, [I love refrigerators.](_URL_0_)
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/92vqgw/at_the_beginning_of_the_20th_century_before/
|
{
"a_id": [
"e38shb0",
"e39v29d"
],
"score": [
13,
9
],
"text": [
"First, people simply bought fewer perishables. Instead of going shopping once a week and storing everything you bought until you needed it, you'd go to the butcher on the day you were actually planning to make roast beef or whatever. This is why milkmen used to be a thing: people got around the fact that they couldn't keep milk for long by simply having fresh milk delivered to their doorstep every morning. The whole production process moved a lot faster: cattle would be herded right into the middle of the city, slaughtered, butchered, and be in the shop the next day, ready for the cook to put on the table in the evening.\n\nAlthough salted and dried meat was used, people didn't rely on it so much after tinned food became common in the 19th century. There are dozens of other things you can do to food to make it suitable for storage: pickle vegetables, turn fruit into jam, turn milk into cheese, etc, etc. Knowing the various methods of food preservation was a skills most housewives would have before it became easy to just buy stuff from a store in the 1950s and 1960s. Today we generally don't consider the fact that a lot of the foods we eat were originally just ways of keeping things edible for a long time.\n\nMost houses had a pantry, a cupboard (or whole room) for storing food. Basements worked too, although in a city most people wouldn't be able to afford to give over a whole floor of their house to food storage. Any place that's dark and cool will stretch out the lifespan of food for a few days. However, people weren't entirely without artificial refrigeration. Iceboxes were very common, unless you were very poor. In rural areas peasants could harvest ice in the winter, store it in an insulated box, and have enough left by summer to store food. The wealthy built ice-houses, big underground bunkers, on their country estates which could store several tons. If you lived in a city then there was also a whole industry for ice-harvesting, which supplied massive amounts of ice and was big business as late as the 1930s.\n\nStarvation wasn't even common in the 19th century in Europe, as the railways eliminated the primary cause: poor food transportation networks. There were one or two exceptions to this when particularly bad natural disasters hit (Ireland, looking at you), but certainly by the beginning of the 20th century famine was almost unheard of in most of Europe. However, that's only peacetime. During WW1 the Allies blockaded the Central Powers, and by 1917 Germany and Austria were experiencing severe food shortages. Several hundred thousand excess deaths during WW1 can be attributed to malnutrition.\n\nAlthough people didn't generally starve to death, higher food prices than America meant malnutrition was more common in Europe. A survey done in Britain during the Boer war (about 1901) showed that a shocking proportion of urban industrial workers didn't meet the height and weight requirement to serve in the army because they had suffered childhood malnutrition. Even by WW2 most Europeans had far fewer calories in their daily diet than Americans, and were on average an inch or two shorter as a result.",
"In Nashville in the 1940s, I remember an “ice man” delivering a huge cube of ice and putting it into a wooden, porcelain-lined box . Perishables would be kept there. I think shopping was daily or close to it. Grocery stores were close by and small. My mother and we two children would walk to the store and bring home groceries in a large paper bag. Milk was delivered. My brother was a toddler so he and the bag rode in the baby carriage. By the end of that decade refrigerators were common. I am 79. "
]
}
|
[] |
[
"https://www.youtube.com/watch?v=TiC8pig6PGE"
] |
[
[],
[]
] |
|
7ns0mf
|
what exactly gets lost when mass gets converted into energy?
|
For example, if hydrogen is fused into helium, the end mass is less than the starting mass. Is something in the protons and neutrons converted into energy while still conserving the characteristics of protons and neutrons? And can you split the helium back to hydrogen and perform the same fusion again?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7ns0mf/eli5_what_exactly_gets_lost_when_mass_gets/
|
{
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"ds43f41",
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],
"score": [
3,
5,
3,
2
],
"text": [
"Nothing gets lost; the law of conservation of energy tells us that. Mass and energy are really just two forms of the same thing. Nothing gets lost from the fusion of hydrogen into helium, the difference in mass is just converted to Energy. And yes you *can* fission helium back into hydrogen but it requires a large input of energy. Lighter elements from hydrogen up to iron create energy from fusion but need energy to fission. For elements after iron, this is reversed.",
"Nothing gets 'lost' per se, that mass represents the energy (and some other stuff) that was originally bound up in the Hydrogen atoms. Helium atoms use less energy to keep everything together than two Hydrogen atoms, so some of that energy gets ejected from the newly minted helium atom. And that's how our sun shines. That little bit of mass that gets transferred into energy, times a very large number, per second.\n\nBonus: [Why does the Sun Shine](_URL_0_)",
"In short: there is energy stored in the interaction between protons and neutrons. When you split them you are changing the state they are in through quantum processes, and the end product is usually the proton, neutron and some radiation. The energy comes from the force that keeps them together (the color force), which you can think of like a spring that stores more energy as you stretch it. Nothing is really lost, but it just changes into other things.",
"Others have already very well answered where the energy comes from, but I see you also asked about splitting it. In theory, one could, but that reaction would require the same amount of energy that the fusion produced, so there would be no gain. In fact, as our energy efficiency is less than 100%, there would be a net loss."
]
}
|
[] |
[] |
[
[],
[
"https://www.youtube.com/watch?v=3JdWlSF195Y"
],
[],
[]
] |
|
2bzf3m
|
When did the guitar as we know it come about?
|
I'm talking about the 6 string acoustic guitar, not necessarily the dreadnought shape because I know that was invented in the early 1900s by Martin. But when did an instrument that you could look at and say, "that's a guitar" come around? And what was its predecessor?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2bzf3m/when_did_the_guitar_as_we_know_it_come_about/
|
{
"a_id": [
"cjasprd"
],
"score": [
4
],
"text": [
"This is an excellent question, and kind of depends on how you define \"guitar.\"\n \nIf you're just looking for the earliest time you could go back in time and look at an instrument and think \"Hey, that looks like a guitar,\" the earliest documented example is about 1200 BC, coming from a [Hittieite Rock Carving](_URL_1_), so we're getting biblical up in here. \n \nHowever, if you want similar to \"as we know it,\" your best bet is probably Medieval Spain. They were definitely in use there by the 1200s, and by the Baroque period of classical music (1500s-1600s...Think Pachelbel's Canon, Handel's Messiah and Vivaldi's Four seasons for stylistic reference) they were occasionally used in compositions in Western Europe.\n \nWhen we get into the modern guitar with 6 string tuning et. al, the earliest example is again Spain, with an instrument called the [Vihulea](_URL_0_), that eventually came to be known as the guitar. (I apologize for linking to Wikipedia, but I'm on my phone and that's the best I can do right now). \n \nHowever, Modern guitar tuning (EADGBE) came from an instrument called the Lute, which was in use from the Ancient Greeks through the Renaissance and on. \n \nSo in summary, if you want something that looked enough like a guitar that Bill and Ted could meet up with a player of the instrument and say \"You play too? Excellent, Dude!,\" we're looking at Biblical Times. Similar instruments, including the lute continued to be played and written for well into the middle ages. \n \nIf you want something tuned like a guitar, we're most likely looking at the lute, which was used by the Ancient Greeks, and they had developed a long-necked (so guitar-esque looking) by 300 BC. \n \nThe 6 stringed version (which is what is commonly used today and I would consider to be the earliest \"as we know it\") came from Spain in the 14 or 1500s. \n\n\n**EDIT** Meant BC, not BS. "
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Vihuela",
"https://tunessence.com/blog/wp-content/uploads/2013/08/hittite-guitar-player.gif"
]
] |
|
325d9s
|
In the year 1750, how different was the standard of living in Eastern Europe (ex. Ukraine, Belarus, Russia) and Western Europe (France, England, Spain)?
|
I typically think of Western Europe as having a higher standard of living than Eastern Europe, but I'm not sure of when that exactly developed.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/325d9s/in_the_year_1750_how_different_was_the_standard/
|
{
"a_id": [
"cq8tqwf"
],
"score": [
2
],
"text": [
"This question has to be narrowed down or the answer can only be yes and no.\nI'm going to assume that you mean the rural population which would be the most representative demographic for the country in general.\nIt could be argued that in 1750, Britain and The Netherlands would have higher living standards that the rest of Europe, the tradtional view of Northwestern Europe as the modernizing and driving part of the world.\nOn the other hand was Scandinavia, aka the rest of Northwestern Europe, dirt poor. The rural population of Sweden, especially the eastern parts, where ravaged by reoccuring famines and epidemics, a cycle which continued up until the latter half of the 19th century. \n\nI have to admit that I'm not very well versed in the living conditions of eastern europe, but I can't imagine that it could be significantly worse than rural Scandinavia, apart from the institution of serfdom and how that impacted on the life of the ordinary farmer. I'm sure someone with better knowledge can correct me.\n\ntl;dr: It was not fun being a farmer in Scandinavia in 1750.\n\n"
]
}
|
[] |
[] |
[
[]
] |
|
30yeqw
|
Why doesn't cream separate into fat and water?
|
When you mix oil and water, you can create an emulsion. After some time, the oil and water separate into layers.
Cream is an emulsion with a lot of fat in water. However, it doesn't appear to separate (at least not on a scale I have observed). Why not? What keeps it in suspension?
|
askscience
|
http://www.reddit.com/r/askscience/comments/30yeqw/why_doesnt_cream_separate_into_fat_and_water/
|
{
"a_id": [
"cpx0375",
"cpxbto7"
],
"score": [
19,
2
],
"text": [
"You have observed curdling, which actually is separation, or the process of \"flocculation\"; it just happens at a slower rate in cream than, say, a mixture of oil and water. Rate of flocculation is driven by several variables, but all boil (or flocculate?) down to the kinetics of the fat molecules, i.e. droplet radius, droplet density, and viscosity of the liquid it is homogenized in.\n\n",
"There are two kinds of emulsions in cooking - temporary and permanent. Emulsions are typically unstable, so once they start to break, they separate quickly. \n\nOil and water shaken is a temporary emulsion. The oil and water molecules are still clumping slightly, so the emulsification breaks rather quickly.\n\nMayonnaise is an example of a permanent emulsion. It uses an emulsifier.\n\nAlmost all milk and cream is homogenized, meaning that the fat droplets are extremely small. The emulsion isn't permanent, which is one reason why milk will curdle, but it does last a very long time (pasteurization helps so curling for other reasons). Cream will last even longer. Since almost all cream I see these days is also UHT treated, cream lasts an extremely long time. Still not permanent, though.\n\n(You can still break permanent emulsions through methods like temperature change.)"
]
}
|
[] |
[] |
[
[],
[]
] |
|
55u5n8
|
What kind of deity or king/ruler is this statue?
|
Looking to see if anyone can tell what religion/empire/region this statue comes from. Someone once suggested it could be Zoroastrian or a combination of Zoroastrian or Bhuddist, but I am not sure. Any insights would be much appreciated!
_URL_0_
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/55u5n8/what_kind_of_deity_or_kingruler_is_this_statue/
|
{
"a_id": [
"d8dylyt"
],
"score": [
3
],
"text": [
"By the craftsmanship, chair, and general style this is definitely Chinese (or Chinese-esque), though nothing stick out at me to identify them. He could be Buddhist god or trickster given the expression, maybe a famous or deified member of Chinese history, although I do not recognise this one in particular, I'm only familiar with the most famous. It could be some sculpted for ancestor reverence, though I doubt it.\n\nSource, Lived in China for several years studying TCM which includes the study of Chinese arts and history."
]
}
|
[] |
[
"http://imgur.com/a/Dvjgh"
] |
[
[]
] |
|
3elwcn
|
why do schools in the u.s punish their students so harshly?
|
I've been seeing several posts about how schools in the U.S suspend and expel their students for what appear to be minor misdemeanours, here in the UK when I was at school you really had to go out of your way to get suspended for longer than a day.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3elwcn/eli5_why_do_schools_in_the_us_punish_their/
|
{
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"ctg5lq0",
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"ctgl84i",
"ctgodhy",
"ctgve3y"
],
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65,
11,
3,
2,
2
],
"text": [
"3 major reasons. \n\n1) Everyone became somewhat insane because of school shootings here, so they can put the color of sense on stupid approaches to school violence. So having an overkill policy about \"weapons\" is not treated as being as dumb as it ought to be. \n\n2) Schools can be sued by parents, and often are, for stupid reasons. This is because of the culture of lawsuits and liability is pretty rough in the US, which is *partly* because we don't have universal healthcare and our healthcare is absurdly expensive. So if someone gets hurt, the parents go bankrupt and then in turn give the school an absurd bill. \n\nIn order to avoid being held libable for literally anything, schools write rules in such a way that they keep their responsibility for anything remotely bad happening to an absolute minimum. They're trying to avoid being held accountable for things because being held accountable can mean millions in damages for something like a broken bone.\n\nSo they turn around and exact the maximum penalty for stuff, so that if it comes down to it in court, they can say they did the most they could have done. \n\n3) Similarly, parents complaining to school boards or politicians about a given school employee gives a very high likelihood of that person getting fired. As such, they'll do anything it takes to avoid being called out by some angry parent to their superiors. So these \"zero tolerance\" policies don't just help the school avoid accountability, it likewise helps teachers, principals, and even superintendents from taking any responsibility for a bad situation. \n\nIf we had universal healthcare, and were willing to tell idiots to shut up and go home, instead of responding to their entitled, asshole demands to fire people, none of this would be necessary. \n\nThere is also the cultural belief among those very same entitled idiots that poor performance on a pupil's part is entirely the school's fault. Since many of our students are indeed poor performing morons (you know, being raised by morons themselves, this makes sense,) schools in general are viewed by these people as incompetent. So it breeds the idea that teachers/administrators actually shouldn't be allowed to exercise judgment at all. \n\n",
"As a US teacher, here's what I've found. America is in an uninterrupted chain of nostalgia for the previous generation's form of schooling. Having had no major disruptive events to our institutions, we still essentially pine for the one-room schoolhouse model. Every school board I've seen has proudly boasted that,\"_____ was good enough for me, so it's good enough for these kids.\"\n\nTrace that back far enough, and we're still essentially in a \"spare the rod, spoil the child\" mindset. The helicopter parent has made us back off, but everyone still wants some kids to just get thrown in solitary.\n\nThis, of course, is not the case for those with their heads in the future, but that's rare here.",
"While some of the other answers are good, a lot of the times you here about these stories beacuse the are not common. Yea you somtimes hear about the kid that got in trouble for making a gun with his finger. But that is not the norm, the kid was just caught in the perfect storm of ashollery of teachers and administrators. Yes there are some shitty reasons kids get in trouble in school here, but generally they are the exception not the rule. \n\nMany times if a kid gets suspended for a longer period of time it is more for the other students then punishing the kid. Removing the interference is a viable way to keep the class going smoothly. ",
"ugh, not sure about that being harsh. i've seen physical punishment given to students for talking back to teachers and i consider it harsher than suspension (i grew up in Asian country).",
"I studied in a middle eastern country public school, I was hit, kicked and slapped by my teachers more than I can remember. America isn't so hardcore..."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
|
t3lw5
|
Why are solar panels flat and not concave?
|
Wouldn't using concave mirrors to gather light and produce a single focal point produce much more power, heat, and energy from the sun than the flat panels?
|
askscience
|
http://www.reddit.com/r/askscience/comments/t3lw5/why_are_solar_panels_flat_and_not_concave/
|
{
"a_id": [
"c4j911d",
"c4j91bd",
"c4j92yi"
],
"score": [
5,
2,
2
],
"text": [
"I think you are confusing [solar panels](_URL_0_) with [solar furnaces](_URL_1_).\n\nA solar furnace typically *does* have parabolic mirrors like you described which reflect sunlight to some concentrated point with the hopes of using the heat energy (by say, boiling water) to generate energy.\n\nSolar panels are much different - they contain [photovoltaic cells](_URL_2_) which *absorb* the sunlight and convert it directly to electricity by the photovoltaic effect.",
"It depends on if you are talking about photovoltaic or thermal harnessing of the sun's energy. For photovoltaic you want the surface to be perpendicular to the sun to be most effective as each cell independently converts energy into electricity, no focusing required. With thermal solar power generation, often mirrors (often concave) are used to focus the sun's thermal energy onto a tower where the energy is harnessed. ",
"I think you misunderstand how solar panels work. The idea is that every spot on the surface of the panel is able to convert light into electricity, so the shape doesn't particularly matter. Focusing the light (above a certain threshold) with a mirror would actually make a panel less efficient because it would use less of the surface area. This is why solar panels are black: It means they're absorbing all (or most) of the light."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Solar_panel",
"http://en.wikipedia.org/wiki/Solar_furnace",
"http://en.wikipedia.org/wiki/Solar_cell"
],
[],
[]
] |
|
4m1kyr
|
Why don't deBrogile wavelengths get infinitely large as an object's speed approaches zero?
|
I'm learning about this in my physics class and we learned tht you can calculate it with the equation lambda=h/mv and just looking at that as something's speed (v) approaches 0 (which happens all the time as things slow down to a zero velocity) it's wavelength should get arbitrarily large. I've asked a couple different teachers and no one has given me an answer.
|
askscience
|
https://www.reddit.com/r/askscience/comments/4m1kyr/why_dont_debrogile_wavelengths_get_infinitely/
|
{
"a_id": [
"d3rwz1k"
],
"score": [
11
],
"text": [
"It does get arbitrarily large; Heisenberg's uncertainty principle implies that if you measure p close to 0 then the wave function will have to be spread out in space. "
]
}
|
[] |
[] |
[
[]
] |
|
htyff
|
How much gasoline do various activities in one's car use up?
|
While driving down the road with music blasting, headlights on, and phone charging, it occurred to me that these activities must deplete my gasoline more quickly than if they were off.
Intuitively, I realize that having a bunch of things on must indeed increase gasoline consumption, otherwise we'd be violating the first law of thermodynamics (and people would just be able to hook their alternators up to their homes and get free electricity).
Anyway, I'm just curious if anyone has ever done even some napkin math on determining how detrimental say a 500 watt draw is on one's average miles per gallon.
|
askscience
|
http://www.reddit.com/r/askscience/comments/htyff/how_much_gasoline_do_various_activities_in_ones/
|
{
"a_id": [
"c1yc902",
"c1ycbrq",
"c1yco6m"
],
"score": [
2,
22,
2
],
"text": [
"You might want to look up 'hypermiling'; it is a method of driving aimed to maximise fuel economy. I'm sure someone in that community has run the numbers on all those sorts of things. \n\n_URL_0_",
"(assuming you're American): 1 hp = 745 watts. Figure your alternator is at worst 85% efficient at converting energy from the serpentine belt into electricity. So, the alternator would need (500 electric watts) * (1 belt watt / 0.85 electric watts) = 588.23 belt watts.\n\n1 watt = 1 J/sec. [One litre of gasoline has about 34 MJ of energy](_URL_0_)\n\nSay your engine is about 18% efficient at getting the energy out of the gasoline and into your alternator. So, you need to burn 588 J/s / 0.18 = 3266.66, call it 3267 J gasoline per second. \n\n(3267 J / s) / (3.4E7 J / l) = 9.6E-5 l/s, or about 2.53E-5 US gallons per second. In one hour, you would burn an additional 0.091 gallons.\n\nHow this affects your fuel economy depends on your rate of travel while you are generating the extra electricity, but as you can see it's pretty negligible compared to the several kilowatts your engine has to generate just to push air out of the way at highway speeds.",
"I'm also interested in how long it takes to recharge a battery to full after starting a car:\n\n - When the battery is fully charged or was just jumped from being empty\n - In summer, winter\n - With AC, headlights, stereo, etc. running.\n - At idle, at highway rpms\n - Big displacement engine vs small displacement engine\n"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Hypermiling"
],
[
"http://en.wikipedia.org/wiki/Gasoline#Energy_content_.28High_and_low_heating_value.29"
],
[]
] |
|
8enpem
|
how do electrical instruments work?
|
Tempted to give my character an electrical voilin for a D & D campaign but i don't really know enough about how they work. how does it change sound, and would running a current through a voilin be enough?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8enpem/eli5_how_do_electrical_instruments_work/
|
{
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"text": [
"No. Electrical musical instruments work by having magnetic pickups which output a signal based on the frequency of the vibrating metal string. This output current is then amplified and converted into sound by the amplifier.",
"When you take a string, stretch it taut, and pluck it, the string vibrates and makes noise.\n\nIn a normal stringed instrument like a guitar or piano, the same thing is happening. The shape of the surrounding instrument is then used to amplify the volume of the vibrating strings.\n\nWith an electric instrument like an electric guitar, the vibrations in metal strings are too quiet to amplify in that way. Instead, a device called a pickup is used to convert the strings' vibrations into electrical signals. These electrical signals are sent to an amplifier, which converts the signals back into a sound loud enough to be heard.\n\n",
"So, electrical instruments rely on a few principles of physics:\n\n1) sound is vibrations traveling through a medium at a certain frequency.\n\n2) higher frequency wavelengths are higher pitched sounds.\n\n3) movement of ferrous materials in a magnetic field produces an electrical current at the same frequency of the movement\n\n4) a moving electrical current produces a magnetic field that changes polarity at the same frequency of the electrical current.\n\nSo you pluck a steel string to create a sound (1) at a certain wavelength (2), which vibrates above a pickup: a coil of wire wrapped around a magnet which creates a magnetic field for the steel string to vibrate in (3); the wire then travels down the length of the pickup wires, out through an output jack, into an amplifier, where the signal gets, well, amplified, and then the electrical current goes into the speaker; the speaker is made of a coil of wire (4) and a static magnet, such that when the magnetic field oscilates, the membrane of the speaker moves and pushes air.\n\nHowever, for a D & D campaign, there is a much simpler explanation for why your violin + electricity = electric violin sounds: \"A wizard did it.\" I had a bard with an electric guitar that had the same explanation."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
4r8011
|
Monday Methods| Reading Historical Fiction
|
Hello and welcome to our 4th of July edition of Monday Methods. Today's topic is the first of a two-parter, as suggested by /u/Caffarelli and /u/Sunagainstgold/.
As historians, the books and journal articles that we read and write are generally in the realm of non-fiction. However, academic writing can often make for very dense or dry reading. People who are non-experts in a particular historical topic may prefer a book that reads more like a novel.
How can readers use historical fiction gain an understanding of the past?
How can we determine what works are of high quality, and which are not?
Can we determine what elements of the story extrapolated and which were drawn from deep research? Will a good author tell us this information in the ~~foreword~~ *preface*? Will they include a bibliography?
**Next week: Part 2- Writing Historical Fiction**
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4r8011/monday_methods_reading_historical_fiction/
|
{
"a_id": [
"d4zegrf",
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],
"score": [
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5
],
"text": [
"I'm only an amateur historian, but I've always used historical fiction as a gateway to learning about the real stuff, and I've channeled that into teaching history to my teenage son (daughter & I do different things, because she has different interests). \n\nHe's not much of a book reader, so I use TV (movies and video games, as well) as my way in. We usually watch at least one episode an evening together, and we discuss it as we go along - so much so that a 45 minute program can sometimes take us 2 hours or more to finish. And when I don't know something, we look it up.\n\nIt's led to regularly spectacular conversations over the years, and the older he gets, the better it gets, because he's got a little more information/experience to work with each time - more frames of reference to work with. \n\nIt's broadened his horizons regarding what kind of things he finds interesting the older he's gotten, too, so I've been able to branch out in terms of subject matter *and* delivery and find him still actively engaged. \n\nFor example, he thoroughly enjoyed *The Tudors*, and found James Frain's Cromwell very interesting, so I will eventually show him *Wolf Hall,* which shows us a different kind of Cromwell (same for Natalie Dormer's Anne Boleyn vs. Claire Foy's and Jonathan Rhys Meyers' Henry vs Damian Lewis', etc, etc, etc.) It would be too dry for him if he hadn't already watched the far flashier *Tudors* and heard all the good gossip there. \n\nI usually watch whatever I show him by myself first - for my purposes, historical accuracy is *great,* but it's not actually the most important thing, because I can correct that as we go along. Instead, what I want is to just find a good story told well, one that will capture his interest, because that's always going to be the best time to engage him. \n\nWatching them first also allows me to avoid spoilers - if he asks a question about something that would give away a good twist in the show, I tell him we need to table that until later.\n\nEdit: I accidentally a word",
" > Will a good author tell us this information in the ~~foreword~~ *preface*?\n \n Two of my favourite authors, Conn Iggulden and Bernard Cornwell, both write on the interpolations and intentional deviations from history and reasons for them in the afterword and give non-fiction book recommendations on the subject.\n \n I think that's a good place for it, since then the readers who care about spoilers won't be spoiled by the info, the ignorant will get set straight on what parts of the story were artistic licence and the enthusiasts get to know why the story deviated from the history they know."
]
}
|
[] |
[] |
[
[],
[]
] |
|
1f4n6o
|
What is the probability of 2 snowflakes being the same
|
askscience
|
http://www.reddit.com/r/askscience/comments/1f4n6o/what_is_the_probability_of_2_snowflakes_being_the/
|
{
"a_id": [
"ca6t9an"
],
"score": [
8
],
"text": [
"Depends on what you define as \"the same\" snowflake (the same or merely looks the same). And how large your minimum snowflake needs to be before you consider it. The smallest ice crystals can easily be alike. For large complex snowflakes there are more possible shape configurations than atoms in the universe.\n\nBasically, there is no fixed formula, but if you consider complex snowflakes (the beautiful ones) the probability of two identical snowflakes is essentially zero. So close to zero, that it is unlikely that any two complex snow crystals that have ever existed on earth have looked completely alike.\n\n\n\n_URL_0_"
]
}
|
[] |
[] |
[
[
"http://www.its.caltech.edu/~atomic/snowcrystals/alike/alike.htm"
]
] |
||
amjl95
|
Do other planets have weather?
|
askscience
|
https://www.reddit.com/r/askscience/comments/amjl95/do_other_planets_have_weather/
|
{
"a_id": [
"efn849y"
],
"score": [
21
],
"text": [
"Oh yes.\n\n- **Venus**: There's hardly any axial tilt, so not much in the way of seasons. The atmosphere is so thick near the surface that it has a huge thermal inertia, so not much in the way of warm/cold fronts. Similarly, because the atmosphere near the surface is so sluggish, winds there never get above a couple meters per second (a few miles per hour), though they do reach higher velocities higher up in the atmosphere. There is rain from the sulfuric acid clouds...although it all evaporates before it hits the ground, so it's more correct to call it virga.\n\n- **Mars**: With a very thin atmosphere and thus very little thermal inertia, there are huge difference in temperature across the surface, ranging anywhere from +20 °C (68 °F) at noon on the equator to -150 °C (-240 °F) at the poles in the middle of winter. Note, however, even those warm +20 °C temps are taken right above the surface; just a meter or two above that, and temperatures can drop by 40 °C, so you could wear shorts but would need a parka. Winds can be up to about 30 meters per second (60 mph), and we've [taken images of dust devils](_URL_0_) on the surface. We've also [seen cyclones](_URL_6_) on Mars, and [imaged ice clouds](_URL_7_) moving across the sky.\n\n- **Jupiter**: Probably more weather than anywhere else, including Earth. Although the cloud-tops are a frigid -150 °C (-240 °F), that quickly increases as you go deeper. There are three main cloud decks on Jupiter: ammonia ice, ammonium hydrosulfide beneath that, and liquid water clouds beneath that. There's constant circulation of these clouds between the white zones and brown belts, as shown in [this diagram](_URL_8_). There are countless oval vortices (including the Great Red Spot, which isn't a storm but rather a region of calm winds) as well as banded jet streams [all swirling past each other](_URL_1_), in a careful interplay of exchanging energy as winds can get up to 180 m/s (400 mph). The water clouds have the most energy, with towering thunderheads 10 times the size they are on Earth, and rain that falls more than twice as fast as on Earth. We've also captured lots of [images of lightning](_URL_5_) on Jupiter, much more powerful than anything produced on Earth.\n\n- **Saturn**: Very similar to Jupiter, but a lot more obscured by the thick orange haze layer. While there's no massive oval vortex like the Great Red Spot, roughly once a Saturn-year [we see a massive storm outbreak](_URL_2_) of white clouds that encircle the planet. Exactly why this happens we don't know, but the hypothesis is that it's some kind of huge convection event that takes 29 Earth-years to build up.\n\n- **Titan**: Although not technically a planet, the largest moon of Saturn has an atmosphere 50% thicker than Earth's, and weather systems that are surprisingly Earth-like...provided that you replace the role of water in our atmosphere with the role of methane and ethane in Titan's atmosphere at around -180 °C (-290 °F). Although here too it's tough to peer through the haze, we've [observed methane/ethane clouds](_URL_3_) building and raining down on the surface, filling rivers that feed into lakes of liquid methane/ethane.\n\n- **Uranus**: When Voyager 2 first flew past in 1986, it was really odd that we observed essentially no weather at all here, just a featureless disc colored blue by methane haze. However, Uranus is essentially rotating on its side, and during that flyby the North Pole was pointed straight at the Sun. As we approached Uranian equinox in 2007, we pointed Hubble back at that planet and [saw an outbreak of methane storms](_URL_4_) in the formerly winter hemisphere. Somehow this planet transitions between quiet and active phases for weather, likely a seasonal effect caused by its enormous axial tilt.\n\n- **Neptune**: With the fastest winds in the Solar System whipping around at 600 m/s (1,300 mph), Neptune [shows a wide variety](_URL_9_) of methane storms as well as dark vortices. Neptune generates almost 3 times as much heat as it receives from the Sun (which admittedly, isn't much when you're that far out in the Solar System). We think this internal heat is what drives the energy of all these storms...but as of yet, it remains a huge unsolved mystery in planetary science what the source of this internal heat actually is."
]
}
|
[] |
[] |
[
[
"https://i.imgur.com/v5tJ2Br.jpg",
"https://i.imgur.com/EgaXHoj.gif",
"https://i.imgur.com/O5eep8c.jpg",
"https://i.imgur.com/ZvH8FlB.png",
"https://i.imgur.com/HdO0TMO.jpg",
"https://i.imgur.com/nlTC8z8.jpg",
"https://i.imgur.com/tdPHGE7.jpg",
"https://i.imgur.com/ZDBpIZh.gif",
"http://i.imgur.com/TbVjwr6.jpg",
"https://i.imgur.com/8YPdlVR.jpg"
]
] |
||
1v4ywi
|
Do we know that pre-historic Megalodon wasn't a hammerhead type shark?
|
From my understanding only the teeth and some vertebra have been recovered. From those alone can we determine whether it would be a hammerhead or not?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1v4ywi/do_we_know_that_prehistoric_megalodon_wasnt_a/
|
{
"a_id": [
"ceowmmn"
],
"score": [
4
],
"text": [
"It's full name is *Carcharodon megalodon*, so it's in the same genus as the great white shark (*Carcharodon carcharias*). Their teeth are so similar that most scientists agree that this is the correct classification, and as far as I'm aware, there's no evidence to suggest that they belonged to Sphyrnidae (the family that hammerheads belong to)."
]
}
|
[] |
[] |
[
[]
] |
|
5dj1v4
|
Why/how did some diseases receive names which sound like peoples' (last) names? (i.e., Crohn's, Parkinson's)
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5dj1v4/whyhow_did_some_diseases_receive_names_which/
|
{
"a_id": [
"da4y56j",
"da4yq11"
],
"score": [
2,
2
],
"text": [
"Chrons was names after Dr. Burril Chron who described it in the 30s, Parkinson's was again after the person to describe it Dr. James Parkinson in the 1800s, ALS is Lou Gehrig's because of baseball player Lou Gehrig who was a very well known person who had it.\n\nAll these are Googleable btw",
"most of those diseases are named after the person that discovered, definitively categorized, or first described the disease. others are named after a famous patient, or the first known patient. It usually comes from diseases that aren't communicable, and thus weren't named before systematic medical or scientific research into them.\n\nParkinson's for example was commonly called \"shaking palsy\". James Parkinson wrote \"an essay on the shaking palsy\" in 1817. I believe it was first described in western medicine by Galen in the early AD times, but it had other names in other areas before then. there's plenty of other eponymous diseases of course.\n\nHuntington's is one that was named after a patient, though the patient was also a doctor. he diagnosed it in himself, his father, and grandfather. as far as I'm aware, the majority of the autoeponymous (self named basically) diseases were also similar in that the person who had the disease also was the first to quantify it *as* a disease.\n\nedit:I noticed you asked for the why/how. The how is because of the above. The why though isn't.\n\nwith diseases, particularly those named and/or discovered in the last two hundred years, there's typically the habit of giving them accurate names. ALS is short for amyotrophic lateral sclerosis. if you learn medical terminology, that means something. It is very descriptive of the nature of the illness. But it doesn't communicate very well to someone without that knowledge. that's why common names come about. ALS is also known as Lou gherig's disease because he was famous and had it. It gives the layman an easier name to pronounce and remember.\n\nthere's been a move to just using acronyms for a while like ALS, but the eponymous ones tend to keep the name because they're already recognized under that name by everyone."
]
}
|
[] |
[] |
[
[],
[]
] |
||
2vkhlq
|
am i legally allowed to build a spaceship and launch into space?
|
If I had the resources and the space to build and launch it. Will I be able to do so without getting in trouble with the government.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2vkhlq/eli5_am_i_legally_allowed_to_build_a_spaceship/
|
{
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"coifp4c",
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4,
7,
2,
2
],
"text": [
"There are private companies that launch satellites on a fairly regular basis. But the FAA has some regulations you'd need to get around.",
"If you live in the US, then you would have to get a license from the FAA (since you don't want it to hit any flying aircraft/satellite and not appear as though you are building a surface-to-air missile).\n\nEdit: [Link](_URL_0_)",
"Space isn't owned by anyone, and once you're there you'd be free to do or go whatever or wherever you wanted. However, depending on where you're launching from, you have to go through some country's airspace to get there, and that airspace is likely heavily regulated. This means you'd have to get clearance from that country's government in order to launch. ",
"You need FAA approval for commercial and high altitude airspace.\n\nBut spacecraft can be just a weather balloon. If you mean a fueled rocket, you would need permits for building a rocked sized bomb and the fuel for that rocket sized bomb. Hazardous material permits for that quantity are very much red taped"
]
}
|
[] |
[] |
[
[],
[
"http://www.faa.gov/about/office_org/headquarters_offices/ast/licenses_permits/launch_reentry/"
],
[],
[]
] |
|
2f5gps
|
what difference will it make if i use soap instead of shampoo for my hair? what if i just use conditioner everyday instead of shampoo, will it be better for my hair?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2f5gps/eli5_what_difference_will_it_make_if_i_use_soap/
|
{
"a_id": [
"ck63uur",
"ck63vpb"
],
"score": [
2,
2
],
"text": [
"Short answer: maybe nothing, or maybe your skin gets a little drier with soap. Nothing but conditioner will leave your scalp a little more oily but you'd adapt to that eventually.\n\nLonger answer: Shampoo is (typically, if somebody chimes in saying BUT WHAT ABOUT THHHIISSS BRAND, please go away) basically a *detergent*. The stuff that cleans your clothes and hair are usually (almost exactly) the same thing.\n\nA *detergent* is a synthetic *surfactant*. A surfactant is broadly something that makes water, well, wetter. It lets the water get into areas it couldn't reach because of tension, and makes water more *soluble*, which lets more things dissolve in it and get carried away. \n\nWhy does being synthetic matter? It doesn't necessarily matter, but it may mean the maker of the product has done a few things to make it a little more gentle than the soap maker has. Of course, for specific brands the exact opposite may be true. Some soaps are pretty darn gentle while some shampoos can be really rough. But, shampoos also often have thickening agents in them that let the makers dissolve less of the detergent in the mix. That makes it easier to get the cleaning product *just right* while also being able to spread all over your scalp. \n\nSoaps tend to be a bit more concentrated in that regard, because there is very little call for them not to be. \n\nSome folks do enjoy mixing their own shampoos by starting with Castile Soap, which comes in a big bottle that you can then mix to your hearts content. It is more 'natural' in the sense that the ingredients are more direct and less chemically derived in tanks from weird sources. Whether that is good or not is totally up to you.\n\n\nFootnote: Conditioner contains a small amount of soap/detergent along with other things. Some people use it exclusively for their hair cleaning.",
"I stopped buying shampoo in the 1980s, and I've washed my hair with a bar of soap ever since. No problems, no complaints, it's a *lot* cheaper, and I still have more hair than most old farts my age."
]
}
|
[] |
[] |
[
[],
[]
] |
||
3x0vex
|
Why are p-values reported as "significant" or not, vs. just giving the value?
|
As I understand the p-value, it's the likelihood that the reported difference is real in the population, rather than the artifact of an imperfect sample, so why do we report it on a binary scale? We don't talk about everyday events being "likely" or "unlikely" because their likelihood is greater or less than a threshold. Furthermore, the term "significant" seems to confuse a lot of people, since it has a lot of meanings and requires an understanding of stats to interpret correctly.
I ask mainly because I encounter a lot of people who hear about and categorize scientific studies as "true" and "false". I wonder if we're maybe setting people who report science, or don't understand stats well, for failure?
Is there a historical reason? Is it just convenient?
tl;dr, there's nothing magical about p < .05 or p < .01, so why are these numbers used as a threshold?
|
askscience
|
https://www.reddit.com/r/askscience/comments/3x0vex/why_are_pvalues_reported_as_significant_or_not_vs/
|
{
"a_id": [
"cy0s9lq",
"cy0tchy",
"cy0wgqa",
"cy1fmwf"
],
"score": [
5,
15,
6,
2
],
"text": [
"Pre-computers, computation of exact p-values used to be very hard, and the only available means of calculating p-values were tables, which were tabulated for a combination of convenience and compactness. Therefore, p-values calculated using tables were relatively low-fidelity, and 0.05 was chosen as an arbitrary cutoff. \n\nToday we know that p-values are a [terrible way](_URL_2_) ([more technical background](_URL_0_)) to communicate about science, and there is a growing movement to [reject scientific results reported only using p-values](_URL_1_). ",
" > p-value [is the] the likelihood that the reported difference is real in the population, rather than the artifact of an imperfect sample\n\nThat's what people want *p*, or rather 1-*p*, to be. But it isn't. \n\nIn hypothesis testing *p* is the probability that the test statistic (whatever that's chosen to be) would take a value at least as extreme as the one observed *if the null hypothesis were true*. If we then see a very low *p* along with a strong signal from the test statistic then we feel justified in rejecting the null hypothesis (the hypothesis that the effect being studied did not occur). The threshold chosen for *p* in any particular study is like a challenge the investigators set themselves to come up with a really good experiment. If the results are significant at *p*≤0.05 that's quite good, if they are significant at *p*≤0.01, that's much better. \n\nAnd, as /u/airbornemint says, until quite recently this was done with standard tables, which provided pre-cooked statistics for certain preferred *p*-values (0.05, 0.01, etc) so everybody tended to use those, and they kind of got baked in to the assumptions about what made a good result.\n\n > I wonder if we're maybe setting people who report science, or don't understand stats well, for failure?\n\nThey aren't being set up, exactly, but *p* is hard to think about correctly and many working scientists are maybe a bit confused about it. It is is all very indirect and confusing, largely because Fisher invented the basics of hypothesis testing in order to try and make sense of large bodies of unsystematic data that never were about testing a stated hypothesis in the first place.\n\n",
"I don't agree with your premise. Most papers I read (biology) report p either as actual numbers, or at the very least on a semi-quantitative scale: p < 0.001, 0.001 < p < 0.05, p > 0.05. \n\nI also strongly disagree with the myriad of purse-lipped finger-wagging papers that scold scientists for seeing a p < 0.05 and instantly accepting the results. Have they ever actually spoken to scientists? Most that I know *don't* accept a p < 0.05 as believable, having seen far too many papers that fail to replicate, and only take p < 0.05 as a mildly interesting observation, not getting particularly interested until there's a p < 0.001 or so. (And yes, I know that there are problems even with that, but the claims by the purse-lipped finger-waggers that p < 0.05 is uncritically accepted are simply wrong.)",
"Another, important reason for having these aritificial separations at p = 0.05 is to minimize the researchers' bias. If you have a pet hypothesis you've been honing for a few years, then it's very likely you will be bending your intepretation of your results to fit your theory. (\"That experiment didn't show what I wanted to? Hm, I guess I didn't collect observations randomly enough. I'll do it properly this time!\")\n\nIf you have a predefined limit at 0.05 and a standardized way of calculating p, then you have a much harder time fooling yourself."
]
}
|
[] |
[] |
[
[
"http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.0020124",
"http://www.tandfonline.com/doi/full/10.1080/01973533.2015.1012991#.VnEOjTZuKxF",
"http://fivethirtyeight.com/features/not-even-scientists-can-easily-explain-p-values/"
],
[],
[],
[]
] |
|
4yc8ip
|
why is crawling on hands and knees so tiring for an adult but babies have no problem?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4yc8ip/eli5_why_is_crawling_on_hands_and_knees_so_tiring/
|
{
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"d6mkq1k",
"d6ml9qv",
"d6mqj1d"
],
"score": [
21,
55,
7,
8
],
"text": [
"I think you are assuming that it's no problem for a baby to crawl around. Babies crawl because they want to start moving around but don't have the strength to stand on two legs yet. So they do what they can, which is crawl. You'll notice that babies crawl for a bit, then rest, on repeat. It's because it tires them out.\n\nFun fact if you want your baby to nap, get them to crawl around. Tires them out.",
"It is difficult for a baby to crawl around. It especially takes very strong core muscles, as well as arm and wrist strength. Babies crawl because they haven't yet learned the more efficient and easier mode of walking.\n\nIt's actually a problem when babies transition from crawling to walking too quickly, because many of their muscles won't get developed as well. Walking upright doesn't really exercise your arms or hands, so children that begin walking quickly can end up with worse fine motor control.\n\nFor adults, why is crawling particularly hard? It's partly lack of experience. We don't put a ton of weight on our arms, so we're not used to using them in that way. It's also partly that we're so much bigger. This puts a lot of weight on our knees/shins which can be very uncomfortable.",
"Yeah it is very intensive for babies when they're first learning to crawl... Takes alot of mental focus and learning to move limbs independently. I never thought it was hard until I had my own child and watched her learn to crawl and could see her increase her breathing and rest frequently. They just don't have the communication to complain basically.... Like man my knees hurt. \n\nSide note. I really believe that we have infantile amnesia simply because being a baby is super unpleasant and absolutely confusing mentally. Constant aches and pains. Trying to always understanding everything but not really getting it. It's frustrating when you cant do something as an adult and equally as frustrating to a baby. So I think we purposely forget it because it's almost like a traumatic experience so our bodies bury it like it's known to do. ",
"When you are born, you spine is basically an open C shape. The curvature develops as you learn to keep you head raise, crawl, stand and walk. A baby's spine is more suitable for crawling in a way an adults is not.\n\nA few other contributing factors:\n\n* babies are light, so there is a lot less pressure on their contact surfaces\n* babies are very flexible\n* babies have proportionately shorter limbs"
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
1b48vg
|
When doing something strenuous, such as lifting weights, why does it feel necessary to tightly close your eyes?
|
I catch myself doing this all the time when working out and I don't know why.
Bad examples, just grabbed them from a quick google search.
_URL_0_
_URL_1_
_URL_2_
|
askscience
|
http://www.reddit.com/r/askscience/comments/1b48vg/when_doing_something_strenuous_such_as_lifting/
|
{
"a_id": [
"c93fybn"
],
"score": [
4
],
"text": [
"I believe what you are talking about is called the valsalva maneuver. Which is defined as trying to exhale with a closed glottis (breathing out without letting air out). This along with the contraction of your thoracic and abdominal muscles makes your core more solid. A solid core better transfers force across your body, such as from your legs to your arms when you are lifting a couch. The involvement of the eyes is further muscle contraction which is unrelated to making your core stronger but goes along the same line as muscle contraction in your core. \n\nAlso studies have shown that thinking about muscles contracting can make you stronger, so closed eyes may make you focus more on the lift, and potentially make the lift more successful."
]
}
|
[] |
[
"http://i.imgur.com/sKxBGpr.jpg",
"http://i.imgur.com/rR3fHbp.jpg",
"http://i.imgur.com/4l8jWKj.jpg"
] |
[
[]
] |
|
26mi5a
|
What physical properties does a pH meter use to measure pH?
|
So basically what the science behind it working?
|
askscience
|
http://www.reddit.com/r/askscience/comments/26mi5a/what_physical_properties_does_a_ph_meter_use_to/
|
{
"a_id": [
"chsenoi",
"chsg9yp"
],
"score": [
43,
2
],
"text": [
"At the tip of the probe there is a thin glass bulb. Inside the bulb are two electrodes that measure voltage. One electrode is contained in a liquid with a fixed pH. The other electrode responds to the pH of the water sample. The difference in voltage between the two probes is used to determine the pH. [Source](_URL_0_)",
"Ion selective electrodes (including pH probes) use a conductive glass or another membrane as the active material. The movement of charges or ions across that membrane is the physical thing you are measuring. The thin walled bottom of a pH electrode is a specifically formulated piece of glass that has semi-mobile sodium ions in the middle and some \"free\" oxygens on the exterior. These oxygen atoms can be either bonded with a hydrogen (or other cation) or negatively charged, and this entirely depends on the number of positive ions in the solution they are touching.\n\nThe inside wall of the electrode is buffered at a certain pH and the outside is in contact with your analyte. When the hydrogen ion concentration in the analyte changes it will change how many oxygens on the outside of the glass are bound to hydrogen or ions, and as this changes on the outside it is balanced by sodium ion movement and charge changes on the inside of the electrode. You then measure what is happening inside the cell to figure out what must be happening outside the cell.\n\nLook at /u/ChE1989 's response for more info on the inner workings of the cell."
]
}
|
[] |
[] |
[
[
"http://omp.gso.uri.edu/ompweb/doee/science/physical/chph2.htm"
],
[]
] |
|
48uksx
|
what's the explanation for physically recoiling when we see something really odd or disturbing?
|
Like, what's the reason behind people feeling really weird when they watch "Goddess Bunny" or something?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/48uksx/eli5_whats_the_explanation_for_physically/
|
{
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"d0mnfvy",
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],
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3,
10
],
"text": [
"We were once animals (less evolved) and animals do it. \n\nThe instinct to recoil is stronger than our cognitive ability. Recoiling probably had an evolutionary advantage. It's just today we are in a bubble of safety, but the instinct hasn't evolved out of us. ",
"Possibly not the answer you're looking for, but relevant: \n\nVSauce made a video touching on things that are creepy or disturbing, and why it makes us unsettled.\n\n_URL_0_\n\nEdit: Upon rewatching this video, I almost want to tag this NSFL, because I get creeped out every goddamn time.",
"It's an instinct designed to increase the distance between you and anything that might be threatening, very quickly, before you even take the time to think about it."
]
}
|
[] |
[] |
[
[],
[
"https://www.youtube.com/watch?v=PEikGKDVsCc"
],
[]
] |
|
1bgpex
|
Does flying an airplane against the rotation of the planet result in a shorter duration of flight vs a flight with the rotation if the planet?
|
Sorry! OF the planet.
|
askscience
|
http://www.reddit.com/r/askscience/comments/1bgpex/does_flying_an_airplane_against_the_rotation_of/
|
{
"a_id": [
"c96ks3j"
],
"score": [
12
],
"text": [
"The plane flies at a certain speed relative to the air, and the air rotates with the Earth, so no."
]
}
|
[] |
[] |
[
[]
] |
|
1syxy6
|
In English, when did "ask" replace "ax" and why has "ax" remained in usage by some groups (like some African-Americans)?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1syxy6/in_english_when_did_ask_replace_ax_and_why_has_ax/
|
{
"a_id": [
"ce2od8c"
],
"score": [
11
],
"text": [
"As your own question shows, “ask” did not replace “aks,” since “aks” is still in common use. You find it not only in African-American English, but numerous British dialects use it as well.\n\nThe better way to think about it is that these are two variants that have always been present. Some people prefer one while others prefer another way. It is true that currently “standardized” versions of both British and American English prefer the “ask” version, and this suggests to many that “aks” is somehow wrong, but this is no more true than the opposite side that you sometimes hear when people say “aks” is older and therefore more correct.\n\nAs for why we have both variants? They are simply metathesized versions, like “pretty” and “purty,” or “three” and “third.” The sk/ks metathesis isn’t common in Modern English, but it’s very common in Old English. For example, it’s common to see both “fisc” and “fix” (fish) and “tusc” and “tux” (tusk).\n"
]
}
|
[] |
[] |
[
[]
] |
||
qcbw6
|
if the calender is based on astronomy, how did they do it in the dark ages?
|
so every 4 years we have a leap year- but how did this start and how did they accurately calculate time and date in the dark ages, when Christians ruled Europe and astronomy was heresy. did they have a leap day every 4 years?
|
askscience
|
http://www.reddit.com/r/askscience/comments/qcbw6/if_the_calender_is_based_on_astronomy_how_did/
|
{
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"c3wgaxb",
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],
"score": [
2,
12,
3
],
"text": [
"The leap-year was invented in ancient Rome (the Julian calendar).",
"I've not heard that astronomy was ever heresy. But in any case Europe didn't change calendars during the Dark Ages. The [Julian calendar](_URL_0_) adopted by Julius Caesar was in use until the late 16th century (later in some countries) when it was replaced by the Gregorian one which we use today. \n\nThe (later) Julian Calendar had leap years _every_ four years, which the Gregorian corrected by having leap years every four years, except for every 100 years, except for every 400 years. (2012 is a leap year, 1900 was not a leap year, 2000 was a leap year)\n\nBut it's not a lunar calendar or some such which requires observation of celestial events. It only requires that you follow the rules and count days. Part of the reason for the Gregorian reform was that the calendar had become increasingly out of sync with the seasons (as defined by when the church was founded), and they wanted Easter to be at the right place.\n",
"It is based on astronomy that is easy to do without any modern technology: the motion of the moon and constellations. If you lived in a time where there were no bright city lights and most people were farmers of some type, you would spend a lot more time looking at the moon and stars and a lot of patterns would be obvious just from paying attention to them.\n\nAstronomy in a general sense wasn't heresy, just certain claims about what the observations meant (i.e. the Earth orbits the Sun). I've never heard about any claims of heresy over stating that the moon has phases or that certain constellations are only visible during certain seasons, which is all you need to make a calendar."
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Julian_calendar"
],
[]
] |
|
14wo2l
|
How were jewels cut and polished prior to the modern era?
|
I'm asking more specifically about the turn into the Common Era. How were jewels cut? I searched and saw how they were set into precious metals, and previous metals were obviously used for a variety of ornamentation. I'm more curious as to jewels and other precious stones were manipulated without damaging them.
If it matters, the reason I ask is because I'm writing a fantasy novel and want to know about the technology that existed and allowed for this type of thing. In this vein, if you know of when certain significant innovations occurred that are relevant, it is also greatly appreciated.
I've been a lurker on this sub for a long time, and while I'm here, I just want to express my sincere appreciation for the quality of everything here. Thanks to the mods, experts, and all of you wonderful people who work to keep the quality of this place so high!
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/14wo2l/how_were_jewels_cut_and_polished_prior_to_the/
|
{
"a_id": [
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],
"score": [
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"text": [
"I had to dig for it but I found it. [link](_URL_0_)\n\nInteresting reading. ",
"I do a bit of lapidary work, [I posed a similar question to other lapidaries on the Gemology Online Forum a while back.](_URL_0_) They posted some good source material.\n\nModern lapidaries can do all their work with synthetic diamond grit. It is precisely graded, so your prepolish will not contain a single coarse particle in a million. Diamond chews through almost any gemstone with nearly equal speed. A pre modern lapidary would have to work hard to procure grit. Ganet (emory) is easy to find (in opaque forms) and usable to grind quartz, but harder gems require some powdered gem as a grit. With motorised equipment, it takes twelve hour to cut a diamond with diamond grit, but only a couple hours to cut a sapphire, wich is the next hardest gem. I imagine grinding sapphire with sapphire or topaz with topaz would be similarly slow. \n\nThey must have had a process to turn identifiable chunks of mineral into grit so fine that it leaves scratches smaller than the wavelength of light. I suspect they started with coarse grit, and let the stone pulverise the grit until it was a fine polish. The technique for grading grit is to drop it into viscous liquid; coarse grit settles out first, then medium, then fine...\n\nfactoids:\n\nAll of the grinding is done wet, diamonds are hydrophobic so diamond cutting is done with oil as lubricant.\n\nRomans and Chinese didn't know how to cut diamonds, but valued small, sharp crytals as engravers for cameos or jade carvings.\n\nThe ancient Greeks and Romans knew diamonds had clevage planes, but they thought the only blade hard enought to split one along that plane was a iron sword that was quenched in goat blood after forging.\n\nThrough most of history, gems were thought to have supernatural power. The lapidary would have been a dusty craftsman, but also an intermediarry with a mystical world.\n\nGems are the oldest global trade, gem dealers would have seen lands more exotic than anyone else, including kings. The gem trade operates, among people who know each other's reputations, on trust. Even today, million dollar parcels of gems are traded on a handshake, by people from different nations and cultures. But fake gems are the oldest and most lucrative con in the book. They are a fake status object to us, like imitation Nikes. To people of the past, they were faulty talismans, you would pay for a crystalized essence of strength or health, and get glass."
]
}
|
[] |
[] |
[
[
"http://www.gemsociety.org/info/history.htm"
],
[
"http://www.gemologyonline.com/Forum/phpBB2/viewtopic.php?f=8&t=14398&hilit=GreenStrong"
]
] |
|
1eaedf
|
What is the smallest radius planet that we could realistically walk on in earth like gravity?
|
I did a calculation to see what the density of a planet with a radius of 10 meters would be if acceleration due to gravity was 9.8m/s^2:
g = Gm/r^2
9.8(10^2) /G = m
m/V where V = 4pi(10^3) /3
So I got 3507612688.83kg/m^3
I realize that there aren't any substances that are this dense within conditions that humans could tolerate (pressure/temp). So what is the smallest planet within tolerable surface pressure and temperature on which we could walk and what would/could be the composition of the planet. Let's also assume that atmosphere chemical composition is negligible (as in, don't worry about Oxygen levels, unless that's inextricably tied to the answer)
|
askscience
|
http://www.reddit.com/r/askscience/comments/1eaedf/what_is_the_smallest_radius_planet_that_we_could/
|
{
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"text": [
"This depends. If you assume a planet can be made out of any thing, take enough of the heaviest known element to have the same mass as the Earth, then determine its radius from its density.\n\nIf you are talking about planets like the Earth, with the same mass and density profile, the answer is the radius of the Earth",
"The densest earthly solid (osmium) has a density of 22.6 kg/m^3.",
"At 22.6 g/ cm^3 , osmium has a density almost precisely 4 times that of Earth's density.\n\nSo, if you had a theoretical planet of osmium with 1/4 the radius of Earth, the total volume would be 1/4^3 = 1/64 less than Earth, and with 4 times the density, 1/16 the mass. \n\nHowever, the surface would be 4 times closer to the center of the planet, so radius effects on the surface gravity would scale as 4^2 = 16 times. Thus the 1/16 mass would cancel the 16 times stronger radius effects to give you Earth-like gravity.\n\n**TL;DR**: A ball of osmium the size of the Moon."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
1rp5hk
|
why after running for a while do my lungs get that painful burning sensation?
|
Once I've been running for a while, eventually my legs will tire before my lungs. But starting out on my first few runs, my lungs "give out" before my legs and I get that painful burning sensation in them. Not asthma, just normal fatigue type feeling. What is that?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1rp5hk/eli5_why_after_running_for_a_while_do_my_lungs/
|
{
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"cdprv3d"
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"score": [
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"text": [
"If it happens in cold weather, it could be simply from the cold air, especially if you're breathing through your mouth. The cold dry air doesn't warm up through your mouth, but it does through your nose. So, when you breathe through your mouth in the cold weather, your lungs get cold dry air in them which can cause the burning sensation.",
"**EDIT: Totally misread your question but I already typed this all up, so I'll leave it for whoever is interested.**\n\n**I thought you were referring to a burning sensation in your legs before you tire. Oops.**\n\n\n\nI'm not an expert, but I think you're referring to the effects of the build up of lactic acid.\n\nAs I understand it, when your body can't deliver enough oxygen to your muscles, it temporarily forms \"lactate\" which helps break down glucose and give you energy. \n\nHowever, one of the downfalls of this process is that you'll eventually experience increased acidity levels in your muscle cells (hence, lactic acid). Now, the whole process doesn't work very well in acidic environments, so the whole process is hindered and this is where you'll tend to get that muscle fatigue feeling. This is all done as a natural mechanism to prevent muscle damage caused by over-exertion. \n\nOnce your body slows down, oxygen becomes more available and the whole system sort of reverses itself and everything is back to normal.\n\nTL;DR: When oxygen is limited, your body resorts to other means that provide a temporary fix, but this process naturally halts and reverses itself before the quick fix causes any permanent damage.\n ",
"can't really say why but i have the same problem.\n\neverytime i run, even if it is just one minute to catch the bus or something, my lungs burn really bad and i have the felling that my heart pounds directly in my throat.\nit takes a solid 10 minutes to get better.\n\ni have been in a great shape running, doing all kinds of sports.\nbut then i was in a hospital for a week after having a Pneumomediastinum.\n\nwhich is basically air leaking out of your lungs to places where they don't belong.\nin my case it was near my heart or something.\ni got an Intravenous therapy for a couple days until they released me from hospital.\n\nthey never found a cause for this in my case.\n\nbut since then my stamina is super low and i can't do sports really well.\nno martial arts anymore. no running. nothing where i jump or something.\nI feel like those bumps cause the burning.\ni can do some lifting or swimming. something that isn't from 0 to 90 or 100% physical effort.",
"In my experience, this was because I was living around cigarette smokers.\n\nIn my family, **everybody** but me smoked. (I was lucky enough to be tuned in to the late 60s propaganda against smoking that began to be disseminated in schools.) As I got to the age where exercise seemed a useful venture, I began running, and after any run I would feel a tired heaviness in my upper chest. To me it seemed a natural consequence after exercise, and it went away after a few consistent runs.\n\nAfter I moved out of the house, I continued running (more off than on, so there were many times I restarted the process). One year I went back to visit my family, and decided because I was on vacation that I could run in the nice winter Florida air. Lo, I felt the same heaviness, but I realized I hadn't felt that in the previous attempts I made away from the family home. \n\nI made the connection then: my mom's smoking habit was affecting my breathing. It shortened my run, at least the first few. I didn't do any double-blind experiments or anything to see the actual differences or how long it lasted, but for me it was a revelation that second-hand smoke was actually affecting me.",
"For me I noticed this lung burning happened when I did not properly warm up my lungs to the air intake required during running which is more than when standing still, sitting, or walking. A slow jog before running will raise your heart rate and breathing rate steadily rather than jumping right up to a running pace. This will allow for a more controlled and comfortable run letting your body reach it's maximum potential (the legs tiring in this instance). This is why warming up and cooling down is so crucial to a good work out or run.",
"I have a somewhat related question. Why after running for a while does the skin on my chest start to itch?\n",
"I get that feeling in my throat.. I suppose it is just the cold air that does it, but is there anything you can do to avoid it?",
"I'm surprised no one's given this answer yet, so here goes:\n\nCongratulations! You're using a lot more of your lungs than you used to. While you're running, you're building up an oxygen debt as your muscles start to use more and more oxygen than you've asked them to in the past, and your lungs are struggling to keep up. As a result, you start really expanding your chest muscles -- does this sound familiar? This can be where side stitches come from. \n\nHowever, your lungs are really only used to taking in so much oxygen. Chances are when you're just sitting around during the day, or walking places, you only take very shallow breaths. The alveoli at the bottom of your lungs don't see much action and they get lazy, but when you start taking deep, heaving breaths you start to use them -- and they don't like that very much. \n\nThis can happen regardless of whether it's cold or warm outside, and regardless of whether you're breathing in through your mouth and out through your nose or what have you (and for the record, I'm pretty sure you can breath through whichever orifices you choose [er, within reason] and breath out through whichever orifices you choose [again, choose wisely] as long as you're getting enough breath. Some people recommend breathing through both your nose and your mouth!)\n\nIn either case, it really just means that you're helping your lungs gain capacity. I would suggest looking up some breathing exercises online, being really conscious of how deeply you breathe during your day, and most importantly, keep running. :)\n\nNinja edited for punctuation and stuff.\n\nReal edit: Someone made a fair criticism that this did not give a very scientific/complete answer. This article from a fitness website seems to provide a reasonable scientific explanation of what's going on, but I can't find any actual primary scientific studies yet...\n\n_URL_0_",
"This has been covered by other people, but if this persists for more than a week without improvement, see a doctor. Otherwise your lungs are just insufficient and are getting an equal workout, except they improve much faster than muscles.\n\nThe first time I ran after 7 years I almost threw up it hurt so bad. A week later I was amazed how well I was improving."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[
"http://www.livestrong.com/article/385817-why-do-my-lungs-hurt-after-running/"
],
[]
] |
|
c3dli0
|
on some websites it says that venus is hotter than mercury because it has an atmosphere, however where does that heat energy transfer to if space is a vacuum?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/c3dli0/eli5_on_some_websites_it_says_that_venus_is/
|
{
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"erq9okb",
"erqa7t7"
],
"score": [
3,
2
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"text": [
"Planets can also emit excess heat through *radiation,* typically by emitting infrared light.",
"There are two sources for heat on Venus. The first is the planet's interior. When the rocky inner planets formed, they were giant spheres of molten rock, and have been cooling ever since. The second is the sun. Photons from the sun carry energy. These photons penetrate the vesuvian atmosphere, and as they strike things on the planet's surface, they're converted to heat. This heat is radiated back up into the atmosphere, but because it is filled with carbon dioxide, the heat is absorbed before it can make its way out of the atmosphere. This trapped heat stays within the atmosphere, building up and raising temperature on the planet. This is the greenhouse effect. Mercury lacks an atmosphere, or at least anything with any substantial amount of greenhouse gases, so heat energy is radiated away quickly."
]
}
|
[] |
[] |
[
[],
[]
] |
|
5mm0s4
|
Eating can raise dopamine, but how exactly?
|
First of all english is not my first language, so pardon me for any grammar mistakes.
Now my question is whether dopamine levels raise while eating food or after, as our body realizes that there's food in the stomach? or how does this process work?
I would appreciate any answers about this exact topic, because I couldn't find much information on it.
|
askscience
|
https://www.reddit.com/r/askscience/comments/5mm0s4/eating_can_raise_dopamine_but_how_exactly/
|
{
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"dc4kq0m",
"dc4mkbq",
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],
"score": [
6,
7,
2
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"text": [
"Oh my, this is a very complex question. What is your background in, I would like to try and get this across in an efficient way, but if you are unfamiliar with any molecular biology, biochem and a bit of anatomy (specifically neuroanatomy) it would be very time consuming to go through it. I would like to rely on concepts introduced in those disciplines to get this across. Otherwise its a matter of saying:\n\nEvolutionary pressures have made us sensitive to sources of high calories. Sweets give the most potent and consistent dopamine release of all foods. When you taste and smell sweets, signals travel to your brain which result in dopamine release, this helps form a feedback loop that reinforces this behaviour. The rest is just the intricacies of this general answer. ",
"Dopamine levels are kind of neither here nor there. \n\nPleasurable activities activate the pleasure circuits in your brain, the ventral tegmental area (VTA). Activating the VTA is what makes things feel pleasurable and in turn makes you want to do them again. Sex, cuddling, talking, eating and all sorts of activities activate the VTA. And so you learn to do them again.\n\nNow it just so happens that that the VTA uses Dopamine as its signalling neurotransmitter. So activating the VTA causes Dopamine release within the VTA. It is in this somewhat limited sense that Dopamine rises when eating. But it is something of a coincidence/happemstance the VTA uses Dopamine rather than some other neurotransmitter. \n\n",
"There are several signals that are sent from the gut to the brain to communicate aspects of feeding. \n\n1. Nutrients traveling in the bloodstream can act directly on the brain (this would include glucose, amino acids, fatty acids, ketones)\n2. Hormones produced by endocrine organs and endocrine cells lining the digestive tract (Ghrelin, GLP-1, PYY)\n3. Physical contraction or distension of your stomach can signal to the brain via the vagus nerve\n\nThese chemical signals will activate centers in the brain involved in feeding, including the arcuate nucleus in the hypothalamus. This nucleus projects to the ventral tegmental area (VTA) dopamine neurons, which will release dopamine in the nucleus accumbens. In addition to the hypothalamic input, the VTA also expresses receptors for some of these feeding related signals produced by the gut, as well as additional feeding related signals produced by the arcuate nucleus. This allows the VTA to respond to the gut directly as well as information from the gut processed in the hypothalamus. VTA dopamine neurons are also influenced by signals which communicate energy stores in the animal, including insulin and leptin. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
36k9wd
|
how and why did the levees in new orleans break during katrina? what should have been done before hand, if anything?
|
The American Society of Civil Engineers is now saying they give the U.S. a score of D+ for our infrastructure and that our roads, bridges, and levees should have been updated years ago. Does that play a role with what happened in Katrina?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/36k9wd/eli5_how_and_why_did_the_levees_in_new_orleans/
|
{
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3
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"text": [
"One of the major levees that failed was the 17th st Canal. Beginning in 1999 it had been refurbished. I remember walking my dog along it from my parents house during the refurbishing.\n\n\n > An upgrade of the canal levees, floodwalls, and bridges began in 1999. The canal was considered in good shape at the start of the 2005 Atlantic Hurricane Season.\n\n_URL_0_\n\n\n\n\n\n",
"Most of the levees in NOLA failed because the height of the flood water exceeded the height of the levee. There are basically two types of levees in that area, the first type is used in most suburban areas and looks like a big, grass covered hill extending down the length of the waterfront (either the Mississippi River or Lake Ponchartrain). The second type is used in more congested urban locations and basically looks like a big cement wall. When the water level gets higher than the levee, water starts to spill over the top and down to the ground on the dry side (called overtopping). If the water level stays high enough to cause overtopping for a while, eventually the water will either erode the structure of the levee itself (as with the hill type levees) or the churning action of the water as it hits the ground will erode the ground underneath the levee, causing a collapse (as with the wall type levees). I think all of the levee breaches during Katrina were caused by overtopping, but there is one other way a levee can fail during a storm. Basically the hill type levees get kind of soggy after they've been holding back water for a while. A really soggy levee isn't necessarily doomed, but it is more vulnerable to being breached if it gets hit by something big, such as a stray barge. \n\nI haven't read the report you referred to, but I'm assuming the poor grade for levees mostly has to do with their height. Sea level has risen quite a bit in the last 50 years (this is an undisputed fact regardless of political opinions as to the cause) and show no signs of stopping. The federal height standards for most of the levees in the country just doesn't cut the mustard at the current rate of sea level rise. Also, very powerful storms of all kinds are becoming more frequent (this is also true regardless of anyone's personal beliefs about why it's happening). Therefore, a levee is more likely to encounter a flood it wasn't designed to handle now than it was to encounter such a flood 30 or 40 years ago. Also, I believe that not all levees are required to follow federal height guidelines so there are a lot of state, county (or parish), and city built levees that are even shorter than the federal ones. So, yeah. All the levees need to be taller than they are now if we want to stay dry in the coming years. \n\nAs for whether or not that played a role in what happened during and after Katrina, yes and no. Yes, the levees failed because they were too short. No because long before Katrina happened, people (including FEMA) knew that a storm like Katrina could hit New Orleans and they knew it would be an epic disaster if it did. I think the reason it happened anyway has a lot to do with human nature (and I say this as someone born and raised in NOLA). First, improving the levees in New Orleans cost billions of federal taxpayer dollars. Before Katrina happened, many Americans wouldn't have wanted to pay that much for levee improvements in a city they didn't live in. Also, people who don't live in areas that are affected by hurricanes often truly have no understanding of how powerful and dangerous these storms can be. Seriously, you have no idea the kinds of stupid s**t people say and do when encountering their first hurricane. Such people often tend to underestimate the need for protective infrastructure in hurricane prone areas. Finally, I think we the locals were also somewhat complicit in our lack of preparation. New Orleans hadn't been directly hit by a hurricane since the '60s and even then, the flooding was contained to one section of town. I think most locals figured that we'd continue dodging the bullet, and even if we didn't, I'm fairly certain that most of us never imagined the damage would be so widespread. To give some perspective, Katrina was forecast to be a monster storm but I know many people who didn't bother to take really important and highly portable objects like personal documents and photographs because they figured the storm would turn at the last minute or that it wouldn't be a big deal if it hit. Basically, I think nearly everyone was complacent because nothing like Katrina had happened in theirs or their parents lifetimes and they couldn't really grasp why they should be doing more. "
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/17th_Street_Canal"
],
[]
] |
|
frhrt
|
How long is a blink?
|
and why does my vision seem continuous and uninterrupted by my eyes being closed?
|
askscience
|
http://www.reddit.com/r/askscience/comments/frhrt/how_long_is_a_blink/
|
{
"a_id": [
"c1i3308"
],
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"text": [
"between 300-400 ms\n\nScientists have found that the human brain has a talent for ignoring the momentary blackout. The very act of blinking suppresses activity in several areas of the brain responsible for detecting environmental changes, so that you experience the world as continuous."
]
}
|
[] |
[] |
[
[]
] |
|
1te4ka
|
how does spinning make thread longer than the fibers of the raw material without falling apart when pulled?
|
I understand (maybe) the process of spinning thread to twist several raw strands together but why doesn't it pull apart?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1te4ka/eli5_how_does_spinning_make_thread_longer_than/
|
{
"a_id": [
"ce71dp4"
],
"score": [
6
],
"text": [
"It's actually quite amazing, though on the scale you are speaking of it can be easily defunct by some finger work, it's actually all friction. The best way to explain it is to see it. Check out one of the best mythbuster episodes of all time to really understand what I'm talking about. Here's a clip from it -_URL_0_"
]
}
|
[] |
[] |
[
[
"http://www.youtube.com/watch?v=hOt-D_ee-JE"
]
] |
|
9olfci
|
what causes a bullet/missile to spin after exiting the rifle?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9olfci/eli5_what_causes_a_bulletmissile_to_spin_after/
|
{
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"text": [
"rivots in tbe barrel are there to give the projectile a spin and thus stabilising it when travelling. ",
"[That would be because of what is predictably called \"rifling\".](_URL_0_) There are ridges on the inside of the barrel that dig into the projectile, and they spiral down the length of the barrel which forces the projectile to rotate along with them. This is actually why they are called \"rifles\" as smooth-bored guns are referred to differently.",
"Rifles have grooving along the inside of the barrel called, conveniently, rifling, which creates spin on the bullet as it travels along the length of the tube and increases accuracy as a spinning object maintains a straighter trajectory for longer.\n\nMissiles, and arrows, have fins which are slightly angled and make them spin as they move through the air for the same reason.\n\nAlso footballs are thrown with a spin to achieve the same result."
]
}
|
[] |
[] |
[
[],
[
"https://www.epicgames.com/unrealtournament/forums/filedata/fetch?id=333526"
],
[]
] |
||
spm2p
|
the different data plans for mobile networks
|
I have an "unlimited" data plan with AT & T, yet Sprint claims in their commercials that they're the only network with "truly unlimited data." What do they mean? I've heard that some networks slow down the processing speeds if you use more and more data. Someone please explain this.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/spm2p/eli5_the_different_data_plans_for_mobile_networks/
|
{
"a_id": [
"c4fwltz"
],
"score": [
2
],
"text": [
"Neither AT & T nor Verizon will sell new accounts with unlimited data for smartphones; instead, you pay for a set amount (e.g. 2GB or 5GB), and you pay overages when you surpass that. T-Mobile also keeps track of how much data you have used in a month, but when you go over their limit (5GB, if I'm not mistaken), they slow your connections down, rather than charging you extra money.\n\nOlder AT & T accounts still have \"unlimited\" data on their accounts, but they have started doing the same thing T-Mobile does. I don't think old \"unlimited\" Verizon accounts have been changed yet, but I could be mistaken.\n\nOf the major four carriers, Sprint is the only one that will sell you a brand new account with truly unlimited service, with full speed no matter how much you use in a month. Unfortunately, depending on where you live, that \"full speed\" may still be terrible; there are lots of places where Sprint's 3G service is horribly limited and 4G service is nonexistent. I am fortunate enough to live in an area with excellent 4G coverage and 3G towers that work great. Your mileage may vary.\n\nWhat does this matter to you? Probably nothing. If you're a normal person, you'll never use more than 1-2GB of data in a month, and you won't hit any of these limitations. I consider myself a power-user: I stream Pandora pretty much every time I'm in my car, and I often download extremely large firmware updates over the cell network, and I think the most data I've managed to use was just over 3GB in one single month — I have ended up under 2GB every month but that one."
]
}
|
[] |
[] |
[
[]
] |
|
z3xwq
|
. maybe a dumb question, but why didn't the vietnam war produce terrorists, like conflicts in the middle-east?
|
I mean, the war left the country devastated, and I'm sure there were a lot of people angry at the US. Why didn't anyone try to strike out at the US?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/z3xwq/eli5_maybe_a_dumb_question_but_why_didnt_the/
|
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"I would think that it didn't produce terrorists simply because Vietnam won the war. Once Vietnam had won, it had all it wanted, so there would be no benefit to it in attacking America further. They couldn't hope to spread communism to America via terrorism, and they had their country back, which meant that other than revenge there's nothing to cause them to attack.",
"Terrorism, particularly international terrorism, doesn't just \"happen\" and not liking a country is never enough motivation on its own to start. Al Qaeda and other extremest groups of that ilk really have a history of at minimum decades or (depending on where you say it \"starts\") centuries.\n\nAl Qaeda doesn't just hate the US, they have a vision of a grand pan-Islamic new caliphate. Their strategy has been to find an area with a Muslim population (but not an exclusively Muslim population), destabilize the region and in the chaos come to power using their dedicated and fanatical followers to create an extreme Muslim government. They did this in the former Yugoslavia, they did it in Somalia, they did it in Afghanistan during Soviet occupation, and they tried to do it in the Philippines with a series of attacks most of which we stopped (including the assassination of the pope). \"Terrorism\" is just a term we have applied to the kind of non-state militias, but they always have a purpose to their actions. It is for the glory of their interpretation of Islam and has the goal of creating a new Muslim caliphate. Al Qaeda litterally means \"the base\" and that is referencing that it is meant to be the first step in the foundation of a global and unified power.\n\nVietnam may hate the US, but there is no group like that in Vietnam. The whole war is seen very differently because of the Cold War, but the Vietnam War started the day after the Japanese surrendered in WWII as a war for national independence, not a war against the US. \n\nHo Chi Minh was not a communist at first but a nationalist. He went to Versailles to plead for independence from France as promised in Wilson's ideal of self-determination, no-one would take a meeting. So when WWII ended, he released a deceleration of independence, declaring Vietnam was no longer a colony but a sovereign nation, invoking Woodrow Wilson, FDR, Thomas Jefferson and the Deceleration of the Rights of Man. \n\nFrance was not willing to let its colony go and the US sided with it's ally France. Ho Chi Minh started getting aid from the Soviets, but only because the US would not help. Eventually France was defeated (surprise) and the country was divided in two. Ho Chi Minh wanted a unified nation, but the US was willing to defend the south. That's what the Vietnam War was about, we tried to keep Ho Chi Minh isolated to the North, but the Vietnamese people are not really divided north/south. To them it wasn't a defense against communism for the most part (though that did exist and why many Vietnamese immigrants came to the US in the 70s) but about the unification of the country. \n\nNow the country is unified, it's economy is improving rapidly, it is normalizing relations with the world. The US left scars for sure, but there is no reason for the Vietnamese to keep fighting us. The war is over and there is no reason why it should continue."
]
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[] |
[] |
[
[],
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|
vedfc
|
Did Nazi Germany have propaganda cartoons?
|
Like Disney cartoons, not comic strips.. ETC
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/vedfc/did_nazi_germany_have_propaganda_cartoons/
|
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"text": [
"E.g. [Der Störenfried](_URL_0_), 1940. Subtle."
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|
[] |
[] |
[
[
"http://www.youtube.com/watch?v=IGUEazGbfSw"
]
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|
1jpeft
|
Which technologies owe their invention and/or diffusion to the porn industry?
|
I know this is kind of "recent" history, but maybe someone has some insight.
I hear a lot about how streaming services, chat rooms, broadband, pop-ups, and live-chat all owe their diffusion throughout the internet to their introduction to porn sites. While many of these make sense logically, I've found it difficult to acquire any actual documentation of this, or at least data I could extrapolate from.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1jpeft/which_technologies_owe_their_invention_andor/
|
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"The lack of data can probably be attributed to a few things;\n\n• Individuals and companies involved with these sort of decisions likely don't have many interviews/discussion in the mainstream\n• The factors involved with the adoption of a technology or solution are likely multifaceted and it would be difficult to control for other market factors.\n• The metrics required to accurately measure this sort of thing are difficult/impossible to acquire (e.g., confidential business marketing discussions).\n\nIt's my understanding it is at least speculatively believed, however, that porn sites very significantly contributed to the adoption of ecommerce as a concept, and payment (debit, credit, charge) cards being accepted in particular. \n\nPorn had had the insofar largely unsolved problem of online payment, which was more or less entirely kickstarted by demand to pay for porn online. Payment cards as a widely accepted, safe, and convenient method for paying for goods/services online probably would have been significantly delayed without the particular benefits online porn provides versus real life. Porn is much more desirable to be purchased anonymously (edit, poor choice of word, I meant 'without the shame of having to hand a human cash for your porn', but it doesn't roll of the tongue) and instantly, which is an experience unique to the Internet. It is my suspicion that the unique attractiveness of this proposition to males provided enough business motivation to allow for it - that is, create the online payment processors model which we are all familiar with today. \n\nThe birth of businesses which rely on these technologies likely would have been delayed until some other market pressure allowed for it.",
"The best source I know of is Jonathan Coopersmith's \"[Pornography, Technology, and Progress](_URL_0_),\" which covers the diffusion of many technologies, from photography to the internet. His main point is that porn consumers are willing to pay a premium for these services, so they allow the technology to mature and drive down the price for later users.\n\nProbably the best example of this (the article I linked to doesn't have a lot about it, but google should), is the standardization of VHS over Betamax. Betamax didn't have very much porn (because of higher capital costs and Sony's discouragement), but on VHS a large percentage of the original movies were porn. Because porn aficionados flocked to VHS, they gained so much market share they helped drive \"regular\" consumers away from Beta."
]
}
|
[] |
[] |
[
[],
[
"http://history.tamu.edu/faculty/coopersmith/coopersmith%20personal/pornography%20technology%20and%20progress.pdf"
]
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|
1utj4t
|
why is that sometimes you go into a "stare"; where your eyes fix to a certain place and slowly go out of focus?
|
You know the feeling, you can be just talking away and suddenly you focus on something, then you just can't be drawn away from that particular spot, your eyes go out of focus and you are just staring. It feels quite comfortable to continue doing this, then you suddenly snap out of it.
I'm not the only one who has this right? Guys?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1utj4t/eli5_why_is_that_sometimes_you_go_into_a_stare/
|
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"I don't know the answer to your question, but the term I've always heard for this is \"zoning out\". You might try asking or searching under that name.",
"Charles (\"Chuck\") in the movie [*The Man Without a Face*](_URL_0_) displayed an extreme case of this.\n\nI do this too, but to a much lesser extent.\n\nEdit: Comments on IMDB refer to it as \"blankout spells\", and also mention Attention Deficit Disorder and a mild form of epilepsy or a trance as possibilities. Hmm.",
"I do this all the time. I can only guess as to why this happens but I have thought about it a fair amount. There are certain moments when your brain focuses on a particular sense at the expense of others. For example, when you close your eyes to listen to something more intently. In these cases, it seems to me that the brain is letting go of certain functions to focus on another and when we daze off, I believe the brain is drowning out other stimuli and focusing on the visual. Like when you stare into a camp fire and find it easier to ignore your thoughts or what's around you for a moment. I imagine that it's like a form of unintentional meditation where you're blocking out a lot of mental stimuli like thoughts and environment and just focusing on a simple visual anchor relieving your brain from all of the stimuli it is usually forced to deal with. Again, just a layman's thoughts.",
"Our eyes work similar to a camera lens. Generally we can look at what is in front of us, and can see the whole picture. But, if you start to look at one specific point and focus there. What is happening is you are focusing on that specific point, so everything else goes out of focus. When it happens, we will start to notice it, and usually it will snap us out of it. We could say it is a minor trance state that naturally happens. When you notice it is happening you refocus your eyes and see the big picture.",
"It's because focusing your eyes is actually much like flexing two different muscles in sync. It doesn't seem like it because you've been doing it almost every waking moment of your life but a lot goes into focusing your eyes on a point in 3D space. \n\nSo when you zone out, you're letting those muscles go slack, for lack of a better term (I'm aware that they're not actually muscles in the strictest sense of the term), giving them a short rest before you go back to near constant exertion.",
"I believe OP's question is more about \"zoning out\" than the actual mechanics of how our eyes work. \n\nI have this happen from time to time. It usually happens under a few certain circumstances but most often when focusing on a concept. I believe what happens is the brain has the ability to automate and filter out unnecessary information in order to concentrate on other operations. When this happens, usually it takes something important to happen as an external stimuli to pull you back into a normal state.",
"This has to do with the muscles that keep your eyes pointed at a certain spot. If they get tired, you can rest a little bit by letting go. Your eyes will drift to a neutral position that is much farther away from you, and thus everything near will lose focus. You can try doing this on a large field outside: relax, lose focus, and then move your head towards something far away. You will see it is focused.",
"I know what you mean OP. I was having a conversation with a buddy of mine on that exact feeling, we were talking about being in the \"present\", before we identify/conceptualize with our brains. It used to happen to me as a kid, the feeling just felt so good. Anything that was happening prior to the \"Stare\" kind of gets muffled out til you snap out of it. I feel like that state is full awareness, not really zoned out because although you are not focused on certain stimuli you are still receiving information from your senses and maybe even more since less information filtering is is occurring. I think this could be the state of mind that we have as children, before we begin to analyze/conceptualize habitually as we get educated. This is my personal observation and attempt to make sense of that state of mind.",
"Okay this could be because I had eye surgery to straighten my eyes out when I was younger. Sometimes my eyes (usually just one at a time) will completely lose focus and be bleary for a few seconds and I have to \"force\" it focus. ELI5 whats happening here?",
"I try to extend that time as long as possible as I kinda think it's a way for me or parts of me to relax and recharge if only for an instant & maybe I need just that.",
"Thank you so much for posting this. I've been looking for an explanation for the longest time. My own rationalization was: \"a visual yawn\". Mine increase in frequency when I'm tired and usually happen accompanied with yawns. ",
"It's not that you're focusing on something, it's that you're not paying attention to what your eyes are seeing. Because your focus is on your thoughts.",
"It's like a yawn for your eyes.",
"I can make my eyes go out of focus. I've always thought that it was interesting and that there is no way to prove this. ",
"To add to the question, whenever my eyes do this and I snap back into attention, my eyes *hurt*. If our eyes had muscles, I'd say it'd feel like pulling/straining them. It burns a little but after awhile it gets back to normal and I forget about it. Is this some sort of condition?"
]
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19u3mp
|
Is it true that as much as 2,3% of ships were being sunken by U-boats during the Battle of the Atlantic?
|
I found this claim [here](_URL_0_).
The specific excerpt:
> The navy admirals were as obdurate as their aerial counterparts and refused for a long time to abandon their belief that small convoys were safer than larger ones despite incontrovertible evidence to the contrary. **Blackett’s Circus proved that each ship in a convoy of 15-24 ships had a 2.3% chance of being sunk compared to 1.1% in a convoy larger than 45 vessels.** (Doubling the size of the convoy only required increasing the number of escorts by 16% because the length of the perimeter requiring protection increased very slowly as convoys grew in size.)
I can't imagine being the crew of a commercial vessel in the Atlantic and being OK with a 1 in 50 chance of dying in a U-boat attack in each of my trips... So my questions are:
**1.** Is this true?
**2.** How was this dealth with by society? Did salaries of ship crew members go up? Did a lot of crew members quit their jobs?
Thanks.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/19u3mp/is_it_true_that_as_much_as_23_of_ships_were_being/
|
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"Lets look at the math of the whole thing : \n\n* First of all - that 2.3 % of all ships were lost doesn't mean that 2.3 % of all men on the ships were lost. Plus the rate soon dropped to 1.1 % with the use of bigger convoys. \n\n* Second : The rate is actually not so bad. Look at the number from [Bomber Command](_URL_0_) for example : \n\n > Of every 100 airmen who joined Bomber Command, 45 were killed, 6 were seriously wounded, 8 became Prisoners of War, and only 41 escaped unscathed \nAbout 3.5 Million men served in the british army in WW2. Of those about 385,000 died or were wounded. So thats roughly 12 %\n\nSo the rate was much better in the convoys. \n \n\n* Third : Are you really affected ? \n\nA typical convoy would either take 14 days (if it was a \"fast\" convoy) or 21 days (if it was a slow convoy). \n\nSo assuming that there is no turn around time, no repairs to to be made and no R & R for the crews the maximum number on convoys you can be on in a year is 25 to 17. \n\nBut those things existed. Plus crews will be switched out, and so on. So while the ship has a chance of being sunk which was at 1.1 % you as a crew member had an even lower chance of diying cause you were not always on the ship. \n\nSo all in all it is a lot less dangerous then it sounds. Especially compared with the other forms of soldiering that were available at the time. \n\n**TL;DR** Its war, people die, the chance to survive as an sailor in the atlantic was actually better then anywhere else. "
]
}
|
[] |
[
"http://www.linkedin.com/today/post/article/20130306150901-25760-the-story-of-the-way-big-data-shaped-world-war-ii"
] |
[
[
"http://www.bombercommandmuseum.ca/commandlosses.html"
]
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|
7oqfmy
|
How was knowledge ‘lost’ after the fall of Rome?
|
Commonly known history states that after the fall of the Roman Empire fell Western Europe went into a backwards period of the dark ages not fully recovering until the renaissance. If so how was this Roman knowledge lost from the West for so long? Or is this understanding of history wrong?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7oqfmy/how_was_knowledge_lost_after_the_fall_of_rome/
|
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"So just looking at western Europe and north Africa (where the empire fell the first and furthest), there are several processes that take place. First, though, it is important to understand what people mean when they say that knowledge was lost. There are basically three things that this can mean. The first is that texts were lost. The ancient world had a lot of authors, a lot of readers, and a lot of books. Many of these were lost. We only have 7 plays by Sophocles, when we know that he wrote many more. Augustine of Hippo writes about the impact that Cicero's \"Hortensius\" had on him; we have lost that book. Sad! A second type of lost knowledge is practical knowledge of how to do things. In many parts of the empire many sorts of building techniques were forgotten. Many technologies disappeared, or were restricted in their use. Ceramic evidence suggests that in Britain people lost the ability to make fast wheel thrown pottery. The Romans had incredible infrastructure; over the course of the fifth and sixth centuries, many of the aqueducts were abandoned or damaged and never repaired. Church buildings got smaller and, at least in certain regions, the use of freshly cut ashlar masonry disappeared. Finally, knowledge of how to run a state disappeared. The Roman government was highly efficient at doing governmental things, like taking the census and collecting taxes. However, in the post-Roman world government became much simpler, and no longer was based on institutions. The chancery disappeared, and records were no longer kept. Knowledge of how to run a society went away. So basically, we have three types of knowledge: texts and intellectual culture more broadly; specific technologies and craft production techniques; and governmental/institutional know-how. All three went away, to varying degrees, in different places (Britain in the paradigmatic example of a place where there was total collapse; in Italy, there was much less loss; in the East, say, in Constantinople or Alexandria, it's hard to know how much loss there was at all). Each went away for different reasons.\n\nFor texts, you have to understand that ancient texts needed to be copied and recopied by hand. There was a transition away from broad literacy and the public consumption of written works and towards a culture of monastic learning that meant that certain types of authors and certain works were more likely to be copied and preserved. We have lots of Church fathers and lots of saints' lives; we have fewer pagan poets. We have Latin comics like Plautus and Petronius because they were thought to preserve important vocabulary for future generations or be good teaching texts for students. We have Virgil for similar reasons. Works that were useless or even worse, perhaps heretical, were not copied. Monastic culture thus both represents a bottleneck for ancient literature and a massve project that saved what we have. Were it not for the monks, we wouldn't have anything surviving in the west. That's because of an overall societal decline in specialization, which is what led to the second type of loss. \n\nRoman civilization was highly specialized. If you were a poor person in northern Italy in the fourth century you could conceivably be eating bread baked from Sicilian grain on red slip ware plates from Tunisia, dipped in fish sauce from Portugal mixed with olive oil from southern Spain (not bad, huh!). Similar situation if you are a soldier on the Rhine or a dockworker in Marseilles or a prostitute in Constantinople. Many people bought clothes on the market or were given clothes woven in the imperial weaving factories by the government. The society was highly specialized with a serious division of labor. As the empire broke down the economy simplified and localized, and in many regions people had to start doing things on their own again, and basically couldn't. There wasn't anyone left who knew how to make concrete or whatever, and no one had the technological know how to make slipware dishes. (A side note: in this period, certain technologies actually spread, such as the heavy plow, which seems to have spread with the decline of ancient slavery, although this is controversial). \n\nFinally, institutions. The Roman Empire was a highly literate, legalistic, lawsuit happy, tax-gathering state (like us!). Once the tax system begins to go, so do the institutions that allow it to exist. The bureaucracy dies, and with it the need for records. With the end of records, lawsuits become more about personal relations and eyewitness testimony and less about being able to access documents. With the end of tax gathering all government institutions go away and are replaced by localized landlord-tenant relationships. With the exception of the church, no one in the West really knows how governments work or what they are supposed to do. No one draws salaries any more. \n\nAnyway, that's pretty schematic. I also fall pretty far on the doom and gloom, everything was a disaster side of the scale. Many others actually think that very little was lost. They are wrong. Here are some good books, going from the more specific to the less specific. Not all of them agree with me, or with each other, but all are good. \n\nGeneral (Brown and Ward-Perkins are the extremes of continuity vs collapse, read both to get a good balance):\n\nBrown, Peter. The world of late antiquity. London: Thames and Hudson, 1971\n\nWard-Perkins, Bryan, The Fall of Rome and the End of Civilization (Oxford, 2005)\n\nFleming, Robin. Britain After Rome. New York: Penguin, 2010. \n\nPirenne, Henri. Mohammed and Charlemagne. New York: Norton, 1939.\n\nAbout books and education, and monks:\nLevison, Wilhelm. England and the Continent in the Eighth Century. Oxford: Clarendon Press, 1946\n\nCavallo, G. and R. Chartier, ed. A history of reading in the West. Amherst: University of Massachusetts Press, 2003. \n\nCavallo, G. 1978. \"La circolazione libraria nell'età di Giustiniano.\" In G. G. Archi (ed.), L'imperatore Giustiniano. Storia e mito, 201-236. Milano : A. Giuffrè, 1978\n\nRiché, Pierre. Éducation et culture dans l'Occident barbare, VIe-VIIIe siècles, 3rd edn. Paris: Editions du Seuil, 1973. (I believe there is an English translation of at least part of this)\n\n\nAbout institutions:\nBrown, Warren, et al., eds. Documentary Culture and the Laity in the Early Middle Ages. Cambridge: Cambridge University Press, 2013.\n\nClassen, P. Kaiserreskript und Königsurkunde: Diplomatische Studien zum Problem der Kontinuität zwischen Altertum und Mittelalter. Thessalonica, 1977.\n\nAbout technology:\nHenning, J. \"Revolution or relapse? Technology, agriculture and early medieval archaeology in Germanic Central Europe.\" In The Langobards before the Frankish conquest: an ethnographic perspective, eds. Giorgio Ausenda, et al., 149-64;165-73. Woodbridge, UK: Boydell Press, 2009",
"What, in particular, do you mean by ‘backwards’ and recovering? Knowledge? The medieval world was better at mathematics than the Roman world. (Indeed, one of the most intense debates of the early middle ages was about mathematics.) They had different writing styles, different philosophies, and religions. But it’s not immediately apparent they’re worse. They had more people who were required to be something like scholars. They invented the school and university educational system. New inventions continued to be made and actually picked up pace. Medieval weapons became better than Roman ones. Etcetera.\n\nThere was material and governmental simplification, but that was a trend prior to the fall of Rome. Economic and intellectual activity and social complexity in the Roman Empire starts falling in the 3rd century and doesn’t start going up again until somewhere between the 7th and 10th centuries. Governmental institutions became more local and hereditary. Things like the census slowed and eventually stopped.\n\nThere were indeed shocks during wars or transitions of power, but the overall trend continued even in peacetime. Likewise, those claiming (legitimately or otherwise) Roman legacy were not more likely to preserve ‘civilization’. Justinian’s armies were far more devastating to Italy than the Lombards.\n\nAs to how much was lost. There’s currently a huge historical debate between the disasterist and continuity hypothesis. The disasterist side, at its most extreme, is the popular conception. There was peace, civilization, and Rome until a bunch of barbarians crossed the borders in the 5th century and burned it down. The continuity hypothesis says that Rome basically never fell. Its institutions continued on, largely uninterrupted, at best with new barbarian heads who were slowly integrated.\n\nI’ll sidestep that question to talk about how the knowledge was lost. There were two mechanisms. The first was normal decay. A book will eventually rot. Paper that isn’t cared for will be gone in a matter of months. With careful attention and almost no use, it can last longer. But for it to be a practical text, it needs to be recopied again and again. Book production and copying both fell as the Empire declined over the centuries. We are told there were less than thirty libraries in the whole of Rome by the end of the fourth century.\n\nRome was also never a highly literate society. There was never universal education and the highest estimate of functional literacy is 20%. The most common number is around 5%. Outside of the elite and priesthood, reading was relatively rare. Elite disruptions, such as destructions of estates, could thus have a disproportionate impact on books. The peasants (and it is proper to speak of fourth century peasants), by and large, were not buying them.\n\nSecondly, trade networks broke down in the 3rd century. The trade networks that started to fray and fall apart meant formerly useful knowledge became useless. You might know how to work certain minerals and ash into concrete, but if you can’t get them all to the same place, what good is that? If it was formerly done in a huge workshop with hundreds of specialized workers, you need a large market to export it to. And that market needs to be able to sell you enough food etc in return to sustain you. This led to the gradual decline of specialized crafts and the knowledge about them. The size of cities shrunk as more people became farmers and crafts became simpler. Again, this was something that started centuries before Rome fell. \n\nThis is all sort of vague and sweeping. So let me compare two scholars’ education. Note, these are exceptional people, but it illustrates something of a point. Augustine of Hippo was born in the fourth century in Roman Africa. Boethius was born four years after the fall of the Western Roman Empire in a barbarian kingdom in Italy.\n\nAugustine was educated from a young age by his mother, with some help of others. At eleven, his parents paid to send him to a boarding school twenty miles away from where he lived. At seventeen, a wealthy friend of the family paid for him to go to Carthage (a yet larger city) to study further. He continued to study in Africa, supplementing his income by teaching, until he was twenty nine. We also know as he moved he gained access to more and more books. Few at home, a little more at his boarding school, and many in Carthage.\n\nBoethius was likewise educated by his father and then (more intensely) by his adoptive father. He attended a local Roman school and his father provided him with tutors as he grew older. He also was said to have gone to Athens and Alexandria for a few years to study at the schools there. There’s some reason to doubt these accounts, but that they were considered believable at the time means that such exchanges must have sometimes occurred. One of the reasons he traveled was to gain access to more books but regardless he was able to become formidably learned. \n\nWhat were the differences? Boethius’ education was less multi-religious than Augustine’s, but this might have partly been due to their geographical differences. Boethius did have a more solid grasp of Christian theology and less opportunity to flirt with other religions. Boethius also travelled more and spoke more languages, probably a reflection of the more multi-ethnic world he lived in. Notably, Boethius spoke Greek, though Augustine himself admits that this was because he hated his Greek teacher.\n\nSomeone might argue I’m cheating by dating this before the destruction of the Roman education system and elite by the Italian Wars. So I’ll throw in Alcuin, an 8th-9th century Briton. He was educated by his family before being sent to York to be educated at the Cathedral and schools there. They were rising stars at the time, attempting to challenge intellectual centers in the Frankish Empire. Alcuin studied there for about a decade before becoming a teacher. During this time he sometimes traveled around Britain to learn and visit collections, possibly as far as the continent. We know he had contacts with places far afield since he was admired at Frankish court.\n\nWhat were his differences? Well, he would have read Boethius and Augustine, for one. There’s no evidence he learned, or attempted to learn, Greek. He would have been multi-lingual, though, including languages Boethius and Augustine didn’t know. He had even less opportunity to flirt with other religions, though more knowledge of and contact with them than Boethius did. He also learned from a combination of old books and new ones meant to provide a more ‘modern’ view, as well as deal with the ‘modern’ curriculum. His education would have also been through the Church. Though it would be wrong to think of Boethius or Augustine’s education as secular or otherwise not religious, it was not through the Church. He also spent a career at a center of learning, as a teacher, and rose to high rank simply as an academic. Boethius and Augustine traveled to specific schools before going into what we’d today call government work.\n\nOnto historiography. The capital R renaissance was invented, at the earliest, in the 16th century, and originally referred to art. It was not used in its modern sense until the 19th century. And at the time, the theory was often part of anti-clerical sentiments. The 19th century historian who popularized the term once called the Catholic Church ‘bizarre and monstrous’. Not exactly a neutral sentiment.\n\nUnsurprisingly, the idea that there was a vast intellectual death when the enemies of the humanists took power, and that it ended when humanism first took root, was favored by humanists. Especially because it also solves an awkward question. It’s very inconvenient for humanists or anti-clerical types to admit the basis of much of their knowledge and educational institutions were medieval and religious. It’s not just inconvenient, it doesn’t fit into the world view that sets science, knowledge, and progress as the opposite of religion. It actively contradicts ideas like, for example, that Christianity contributed to, or actually caused, the fall of the Roman Empire.\n\nTo this end, a narrative that othered the people of the medieval period and exaggerated the similarities of the Roman period emerged. They treated the Church, often with little cause, as an anti-intellectual force and the Romans as pro-intellectual. They attributed the significant advancements as coming from the outside, either the ancient world or the Muslims. The scholars of the middle age become nothing more than transmitters of other people’s knowledge, at best. They’re often (without evidence) accused of actively destroying it. Like most ideologically convenient histories, it's simplified and inaccurate in many ways.\n\nWorks Cited:\n\n* Allott, Stephen. Alcuin of York, his life and letters\n\n* Throop, Priscilla, trans. Alcuin: His Life; On Virtues and Vices; Dialogue with Pepin\n\n* Noel Harold Kaylor; Philip Edward Phillips (3 May 2012), A Companion to Boethius in the Middle Ages\n\n* Marenbon, John, Boethius, Oxford\n\n* Marenbon, John, The Cambridge Companion to Boethius\n\n* Augustine of Hippo, Confessions\n\n* Brown, Peter. The Making of Late Antiquity\n\n* Jones, A. H. M. The Later Roman Empire, 284–602: A Social, Economic, and Administrative Survey\n\n* Macgeorge, Penny. Late Roman Warlords\n\n* MacMullen, Ramsay. Corruption and the decline of Rome\n\n* Caferro, William. Contesting the Renaissance\n\n* Summit, Jennifer. \"Renaissance Humanism and the Future of the Humanities.\"\n\n* Trivellato, Francesca. \"Renaissance Italy and the Muslim Mediterranean in Recent Historical Work,\"\n\n* Alaric Watson, Aurelian and the Third Century\n\n* H. St. L. B. Moss, The Birth of the Middle Ages\n\n* Ferdinand Lot, End of the Ancient World and the Beginnings of the Middle Ages\n",
"In addition to the excellent answers we've got here, in [this thread](_URL_0_), /u/Tiako and /u/bitparity discuss quality of life after the fall of the Roman Empire, which, will not a strict answer to OP's question, certainly has a lot of overlap and will probably prove to be of interest."
]
}
|
[] |
[] |
[
[],
[],
[
"https://www.reddit.com/r/AskHistorians/comments/5bfw2n/the_fall_of_the_roman_empire_is_typically/"
]
] |
|
atalsn
|
have we been able to find the center of the universe mathematically?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/atalsn/eli5_have_we_been_able_to_find_the_center_of_the/
|
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"There is no center of the universe. You can pick any point arbitrarily and it would be just as valid.",
"We don't know if the universe has a center because we don't know if the universe has edges or if it goes on forever.\n\nWhat we do know is that the observable universe, which is the part of the universe that we can see, looks pretty much the same everywhere in the sense that it has much of the same things that behave in much of the same way.\n\nIf the universe is infinite, meaning it goes on forever in all directions, it would not have a center. If it has some type of shape, it might have a center but not necessarily.\n\nIf it has finite mass, which is a limit amount of mass, then it does have a center of mass and a center of gravity.\n\nIf it does have boundaries then we are tasked with the question of what the nature of those boundaries are. I imagine they might be imperceivable to us. In fact I personally think that might be the case.\n",
"The universe does not have a center. The big bang did happen in a \"place\". It happened everywhere at once, and everything is expanding in all directions. Think of the surface of a sphere (NOT implying that the universe is a sphere). The surface of a sphere has no center."
]
}
|
[] |
[] |
[
[],
[],
[]
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||
10clur
|
OK Reddit, can someone please explain to me the idea of someone's 'reaction time'?
|
Hear me out. I basically don't understand the idea that different people have different reaction times.
Consider the classic test where a ruler is held by someone and dropped, allowing people to measure their reaction time by how far the ruler falls before it is caught. My interpretation would be that, upon the ruler dropping, the reaction time is the time that is required for an optical signal to be recognized, sent to the brain, and subsequently sent to the muscles of the hand to close the fingers.
My question is this: is the limiting factor of this not just the speed of transmission (i.e. the speed of light)? I would think this should be pretty constant, so how can there be such a significant difference in the overall trait of 'reaction time' from person to person? I'd love to hear!
|
askscience
|
http://www.reddit.com/r/askscience/comments/10clur/ok_reddit_can_someone_please_explain_to_me_the/
|
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"Everyone brain processes information at different speeds. The signal of seeing the ruler drop has to go through many parts of the brain.",
"The transmission speed isn't the speed of light. It's very electrical in nature, but not completely analogous to an actual transmission line (which in fact doesn't go at the speed of light either). In neuronal signal transmission, there is a lot of mechanics involved, such as sodium and potassium channels (and others) opening and closing to let ions flow through. Also, every time a signal reaches the end of one neuron and starts flowing down the next, neurotransmitters have to be released through small vesicles. All of these things take time, and generally occur on the order of milliseconds."
]
}
|
[] |
[] |
[
[],
[]
] |
|
8p4l4l
|
where does the term "in-law" come from?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8p4l4l/eli5_where_does_the_term_inlaw_come_from/
|
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"Marriage is a legal construct: when you are wed, you are bound to another person and their family legally. For a very long time, marriage was about the consolidation of wealth and property more than romantic notions of couplehood. So the family of your betrothed become your family, not in blood, but legally... your mother “in law” but not in blood, etc. ",
"It's literal. My sister in-law is not my sister by blood, but my sister by marriage. Marriage is a legal thing (or a religious thing if that's your shtick), so my sister by marriage is my sister by law. She's my sister in-law."
]
}
|
[] |
[] |
[
[],
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||
6bqqrx
|
What happens on an atomic scale when water is boiled?
|
So my college entry biology professor (with a doctorate) just told my summer school class that when water boils, the hydrogen and oxygen atoms split and bind to each other, forming H2 and O2. I have always been taught that water vapor is just water molecules that are heated to a gaseous form.
Also, if what he said is true (which at this point, I have trouble believing) than why does the ensuing H2 gas and O2 gas not react with my kitchen stove and blow my house apart when I do something like cook pasta?
|
askscience
|
https://www.reddit.com/r/askscience/comments/6bqqrx/what_happens_on_an_atomic_scale_when_water_is/
|
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"Oversimplified, but when water boils, enough heat has been added to water molecules that they gain kinetic energy, causing the interactions between water molecules to become more transient and letting some water molecules escape into the gas phase (water vapor). \n\nIn contrast and also oversimplified, in order to make H2 and O2 diatomic gas molecules from water molecules, the molecular bonds between the hydrogen atoms and oxygen atom in a water molecule must be actually broken in order that H2 and O2 molecules can form, such as in [electrolysis](_URL_0_). ",
"Your biology professor is incorrect. There is no chemical change in the water. The H2O does not split into H2 and O2.\n\nYou have been taught correctly, that water vapor is gaseous water.\n\nFor your hypothetical, if you *did* have H2 and O2 gas, they wouldn't necessarily explode unless you have an ignition source at a temperature above the flash point (so, a gas stove). Alternately, they will spontaneously combust if they are heated above the autoignition temperature of hydrogen (~500°C).",
"*Preamble: Other people have pointed out your teacher is wrong. I decided, for whatever reason, to go a bit further...*\n\nDepends what you mean.\n\nOn the *individual* molecular level, next to nothing.^(1)\n\nOn the level of a molecule and it's neighbors, quite a bit more.^(2)\n\nOn the level of the entire ensemble of waters? Something just shy of magic.^(3)\n\n***\n\nMore detail if you're interested:\n\n1. If you were to zoom down so that you were, say, half the size of a water molecule and could only view that individual molecule (without the surroundings), you would be hard pressed to notice the difference in a molecule in liquid versus the gas phase -- particularly at temperatures close to the boiling point. There may be some aspects of the way the hydrogens behave, dynamically -- the angle between them may oscillate in a more unpredictable way in liquid versus gas, the oscillations of the hydrogen-oxygen bonds may be affected, etc. -- but all of these affects would be rather subtle. The covalent HO-H bond in water has an energy of magnitude [~500 kJ/mol](_URL_2_), whereas a hydrogen bond in water typically has an energy somewhere between [5 and 15 kJ/mol](_URL_1_). The energy associated with H-O-H bond angle is more complicated, but it is largely unimportant for liquid to gas phase transitions.\n\n2. Water molecules are in contact with a number of their neighbors. As the temperature increases, these contacts don't get fewer (maybe slightly), but they do get more fleeting. Waters are jiggling around and bumping in to each other and a much higher clip, until they transfer enough energy to one or another in such a way as their energies on an individual molecular level (kinetic mostly) are higher than the energy of all the hydrogen bonds keeping them bound to their neighbors (e.g. for 8 hydrogen bonds, roughly 80 kJ/mol of kinetic energy is needed for an individual atom to break all it's contacts with neighbors and resist forming more). This is how water *enters* the gas phase, on an individual molecular level.\n\n3. Thermodynamics (the theory by which we study phase changes like this), there are really only a few axioms (I'm borrowing heavily from [Callen](_URL_0_) here). \n\n* First, there exist states of systems called \"equilibrium states\" in which the properties of the system are entirely determined by only a small number of variables: The energy (U) of the system (Kinetic, Potential, etc.), Number of Particles (N) in the system and the Volume (V) the system occupies -- these are not the only states the system can be in, we only posit that states like this exist. \n\n* Second, there is a function of these variables called the \"Entropy\" (S), which has a very important property: let's say we divide our system in to subsystems so that the energy now has two parts (e.g. for division in to two subsystems, U = U^((1)^) + U^((2)^) ), and so does N and V (similarly divided); the values that those variables U, V and N take on at equilibrium in the absence of a constraint (read: divider) are those exact values which maximize the entropy of the total composite system at equilibrium **with** the constraint. \n\n* Third, S must be additive over the subsystems (S for composite system is the sum of over the subsystems), continuous and differentiable (just to save us all some headaches), and strictly increasing function of the energy (U goes up, S goes up).\n\nFrom these three rules, and honestly very little more, all of Thermodynamics springs forth as a series of mathematical manipulations. For example, if you know any calculus, let's take the derivative of our entropy function, and to make things easier, let's assume the number or particles doesn't change (there are two independent variables that can change the entropy so it's rate of change will have two parts):\n\ndS = (dS/dU)*dU + (dS/dV)*dV\n\nWe just *decide* to call that term (dS/dU) the \"inverse temperature, 1/T\" and we call that term (dS/dV) the \"pressure over temperature, P/T\". We decide to do this because if you investigate the properties of those differentials, in light of the requirements we laid out for the entropy above, they behave **precisely** as we expect our everyday notions of temperature and pressure to behave (it really is beautiful). So, rearranging, we have:\n\nTdS = dU + P*dV,\n\nwhich may be familiar to many first semester physics students. Also importantly, once you have a functional form for the entropy as a function of U, V, and N, you can rewrite the function in terms of these derived quantities (P, and T ^(and also one called the chemical potential which I'm too tired to mention))\n\nImportantly, all the properties of the system you are trying to model are consequences of the form of the entropy function S(U,V,N) (there are many functions for entropy that follow the rules laid out above.) Phase transitions arise as \"jumps\" or discontinuities in the entropy/energy as a function of temperature/pressure.\n\nAll of this is very abstract, which is why I say that on the ensemble level, phase transitions are something close to magic. Indeed, thermodynamics still feels like magic to me, and I work with it every day.",
"If boiling water split the molecules, making macaroni and cheese would become a life and death situation. You'd end up with two flammable gasses being emitted near a flame or heat source or both (depending on gas or electric) as you said.\n\nEdit: think of it this way, water boiling is a phase change caused by the addition of energy to the liquid water. Same as water freezing is a loss or removal of energy. No chemical reaction, merely addition (or subtraction) of energy causing a phase change.\n\nEdit 2: sorry, used flammable for oxygen loosely. Oxygen is an oxidizer. As evidenced by (I believe?) the Velcro catching fire in the apollo 1 capsule. Pure oxygen isn't good unless you medically need it, and then there are precautions.",
"A substance can exist as a liquid if the intermolecular forces *between* molecules overpower each molecule's tendency to fly away (due to its kinetic energy). So when you heat a pot of water, you are transferring energy to each water molecule in the form of atomic vibrations. Water molecules can form what are called hydrogen bonds with other water molecules. These are not covalent interactions, but rather interactions between partial positive and negative charges on the hydrogen and oxygen atoms, respectively. If you give a water molecule enough energy (heat) to break all of its hydrogen bonds with neighboring molecules, it will be free to fly away\n\nTo suggest that boiling water forms H2 and O2 is a ridiculous statement coming from a Ph.D. scientist"
]
}
|
[] |
[] |
[
[
"https://en.m.wikipedia.org/wiki/Electrolysis"
],
[],
[
"https://www.amazon.com/Thermodynamics-Introduction-Thermostatistics-Herbert-Callen/dp/0471862568",
"https://www.ncbi.nlm.nih.gov/books/NBK22567/",
"https://en.wikipedia.org/wiki/Bond-dissociation_energy"
],
[],
[]
] |
|
17v2se
|
What's the likelihood that the legacy of King Richard III was mostly Tudor propaganda to secure their claim to the English Throne?
|
With the remains found buried under a car park in Leicester now [confirmed to be those of King Richard III](_URL_1_), I’d kind of like to hear how much of what we ‘know’ about him is likely true, and how much was spun by the Tudor dynasty to secure their comparably weak claim to the throne.
My understanding of this period in history is limited to what I was taught in school (very little between the Norman Conquest and the late Tudors), so I only really have what’s been in the [news recently](_URL_0_) to go on. There have been a lot of points made that the story of a hunchbacked tyrant was not true and that Richard was actually a well-respected Duke who was simply betrayed by those he thought he could trust.
So I guess my question is really which version of events the historian community believes is more accurate and why?
Edit: Formatting
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/17v2se/whats_the_likelihood_that_the_legacy_of_king/
|
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"Terry Jones (of Monty Python fame) did a fun series of shows called \"Medieval Lives\" with each episode focusing different types of people in Medieval Europe. His episode on [kings](_URL_0_) covers the three Richards.\n\nI can't speak to it's historical accuracy but it's a well done program.",
"The problem is that the majority of the contemporary and near-contemporary documents about him are all likely to contain some bias. Shakespeare's play is obviously pro-Henry VII, since he's writing at a time when Henry's grand-daughter is on the throne. Shakespeare's Richard III is slightly less obviously suck-up propaganda than his Henry VIII, but when you read the play it's pretty clearly written to make Richard look like a bad guy so that the usurpation by Henry VII is less usurpation by someone with a big army and a tenuous claim and more \"victory over a tyrant\".\n\nJosephine Tey's book \"Daughter of Time\" is a famous attempt to reclaim Richard as a good guy, but a lot of her evidence also comes from sources inclined to be biased. The Richard III Society is all over these documents, too. However, the contemporary sources from Richard's reign that talk about how awesome he is (from the North of England) are, hello, written at the time he is not only king of the entire country, but also feudal lord of the places the reports are coming from. You don't get a lot of documents saying \"hey, the guy who has a lot of power over us is an asshole, and we don't care who knows it\".\n\nAs far as the killing of the princes in the tower is concerned, there are lots of theories. Current historians (like the ones quoted in the news yesterday and today) appear to be tending towards \"yeah, he did it, but anyone would have in that situation\".",
"Funny you ask this question, since last night I was listening to a lecture on this exact topic. I have no sources for you at the moment, but the lecturer mentioned a theory that paintings of Richard III were subsequently painted over by Tudor claimants to make Richard appear more grotesque and hunchbacked. You'll have to research this yourself since, like I said, I have no source. But it may be worth looking into if you're still curious.",
"If you're interested in a historical fiction novel that portrays Richard III in a more favorable light, I would highly recommend *The Sunen in Splendour* by Sharon Kay Penman.\n\nEDIT: Corrected author and spelling of title.",
"I have read at least a dozen books about Richard III and the fate of the princes in the tower. The matter is still controversial.\n\nWhat is know is:\n\n- Richard was a very well respected administrator of the north of England for his brother Edward IV. He did also fight with valor for his brother in the war of the two roses, and his loyalty was never in doubt (unlike that of their brother, the Duke of Clarence).\n\n- at the death of Edward, in the spring 1483, the heir was a minor, and Richard was supposed to be the regent.\n\n- Richard was _not_ loved by the widow queen and her family, the Woodvilles (and the Woodvilles were not loved by most of the old nobility of England)\n\n- when Richard did come to the south of England, he did put under arrest a number of Woodvilles and of their allies, but then proceeded with the organization of the coronation of his nephew.\n\n- after a short while, it was \"discovered\" that the old king had married (more like a binding betrothal) another women before marrying Elizabeth Woodville; so their sons were illegitimate and Richard was the \"true\" king.\n\n- so Richard did take the crown (and had a number of Woodvilles and courtiers of his late brother executed to consolidate his power)\n\n- some times after the coronation of Richard III, all traces of two sons of Edward IV disappear completely; after the summer of ~~1485~~148__3__, they are not mentioned anywhere\n\nDid Richard decide to usurp them and then killed them ?\n\nHe did certainly have the motive and the capability. Also he had history to worry about. The last two times there had been a king minority in english history the uncle that was regent had been subsequently used as a scapegoat when the king did get the power.\n\nBut there is no _proof_ that he did it, and so a number of other theories have arisen during the years. It could have been Buckingham (an ally of Richard that some months later betrayed him) or, assuming they lived somewhere hidden for two years, Henry VII when he come to power after defeating Richard at Bosworth in 1485 (Henry _did_ have a number of other surviving Plantagenets killed during his reign).\n\nWhat is certain is that the Tudors did have all the reasons to damage his reputation. They did take the kingdom from him, and their claim to the crown of England was _very_ faint (they were from a bastard branch of the Plantagenets, and only by a female line).\n\nAnd Shakespeare was working under the Elizabeth I, the granddaughter of Henry VII.\n\nSome book sources:\n\nP. W. Hammond, Anne F. Sutton - Richard III: the road to Bosworth Field\n\nAlison Weir - The Wars of the Roses\n\n\n\n",
"I can't speak to much of the iconoclasm of Richard III, but the thing I found most surprising in all this is that the skeleton has scoliosis.",
"**A related semi-meta question for our Richard III experts:** They're going to re-inter the remains of Richard III in Leicester Cathedral. Is there a particular objection to sending them to Westminster (or York, or some other place of regnal importance to him), or is it (as suggested) simply a matter of archaeological best practice as the closest consecrated ground? I've heard one suggestion that it had to do with the lobbying efforts of the Leicester city government, who really would like the tourist draw of having him still there, given that they are opening a museum next to the Greyfriars site.\n\nIt still seems confusing to me that, in England, Richard's burial place and even the whole site was \"lost.\" Given that he was the only post-Norman Conquest monarch whose locale was unknown, it seems quite rare. Is this truly mere accident or effacement? (This may be more speculative, but I'd be curious of the opinions of our late-medieval England folks.)\n\n[edit: In even more of a lark, given that the skull has been photographed and evidently scanned, can we reconstruct his actual face now?]",
"Does anybody know if this would have any impact of identifying the skeletons found in the 1930's as the princes in the tower? Is it possible I know it was via the maternal DNA but now the body is confirmed as Richard is it possible to identify the Princes bodies and prove once and for all whether they were legitimate.\n\nI know one theory suggests that the queen was unfaithful, and also ofc the blonde children from a dark haired father.",
"Technically out of my field, but the English Monarchs are my hobby. \n\nRichard III's legacy has to be seated in the context of the War of the Rose violence, the infighting, and relative instability. Also relevant, however, is amount his administrative reforms, often depicted as duplicitous, became hall marks of later English Policy. The last question is motivation; did Richard genuinely care about the throne, and legacy of England, or only about his own hide, or was he simply greedy?\n\nThe decision to put the Princes in the tower was, as scholarship accepts, for safe keeping. They were the Yorkist princes destined to inherit the throne, however both Prince Edward (who would be the 5th) and Prince Richard (who would be the third) were in minority, and unable to take the throne. Their Yorkist Uncle, Richard, was named regent. Historically, the powers of Regency have been restricted, and often was a time of turmoil and weak reign. Richard, I think, rightly identified this risk and placed himself in a position of power to proverbially head it off at the pass. Whether this was done out of greed, or if he truly killed his nephews out of malice, I can only speculate on.\n\nImportantly, however, are the reforms that Richard III championed. He instantly threw himself at eroding the power base of Northern Nobility (York/Lancaster alike). This was geared solely towards an attempted return of peace and stability, with the central and consolidated power in the Monarch. He also purged the Privy Council and Privy Chamber of strong landed nobility, and favored the rise of \"New Men\", a burgeoning trend that would spur the Tudors to enormous success. In doing so he made many enemies - regardless of what existing documents of the time might say that extol him, they're often written with a feudalistic slant. In his defense, he was trying to improve the Kingdom and reign in decades of violence by striking at the root of the problem. He unfortunately was killed in the Battle of Bosworth in 1485 before this could be accomplished, so we have only a snapshot of the attempted reforms he wanted to implement. \n\nWhether his style of rule was heavy handed, sly, or duplicitous, it was never the less effective. There is an old adage that states that the most necessary changes are often the most unpopular, and I think that holds true for Richard. He was the first to attempt to shift the status quo, and in his relatively short reign he laid a groundwork for later Tudor policies. Henry VII came to the throne after the Battle of Bosworth (having slain Richard), and continued many of the reforms, and identified many of the same problems - strong nobility threatened Monarchical control, necessity of King's influence needing to be pervasive, appointments of fiercely loyal \"new men\" who rose by merit and owed you sole allegiance, etc.\n\nBased on the continuation of many of the same reforms, I doubt Richard's legacy was a propaganda smear campaign. Henry VII had distant ties to both houses York and Lancaster, and strove to unite the country rather than divide it. I don't feel as though a propaganda campaign against his reign would accomplish any degree of unity, or increase Henry's appeal. Henry himself was quite unpopular especially towards the end of his reign, but his own succession was secured financially and physically, and he had also successfully weakened those who would potentially oppose him, or his line - exactly as Richard was trying to do.",
"Well, the question of who killed the princes in the tower will probably never be resolved, and I'm not qualified to judge whether Richard was a capable administrator and ruler or not. However, I can say that Richard III died like a true knight at the Battle of Bosworth Field. \n\nWhen he saw Henry Tudor and his retinue expose themselves, Richard and his personal guard charged directly for the rebel leadership. The fighting was so close that Sir William Brandon, who was Henry's standard-bearer, was killed. That implies that the fighting was taken practically to Henry himself. Henry, however, refused to take Richard on in combat himself, and eventually the king was overwhelmed by infantrymen, unhorsed, and killed. \n\nRichard III was the last English king to die in battle. Scoliosis would probably make you medically disqualified to serve in combat nowadays, but Richard was clearly a capable knight regardless. I leave you now with this quote, from the Croyland Chronicle:\n\n > At length a glorious victory was granted by heaven to the said earl of Richmond, now sole king, together with the crown, of exceeding value, which king Richard had previously worn on his head. For while fighting, and not in the act of flight, the said king Richard was pierced with numerous deadly wounds, and fell in the field like a brave and most valiant prince.\n\n-Part IX of the Croyland Chronicle, 3rd Continuation (author unknown)\nFor those who would like to read an English translation of the whole chronicle, it can be found online, hosted by the Richard III society: _URL_0_\n(edited for formatting on the quote)",
"Corollary Question: I had heard that Richard III, before becoming king, had a reputation as a kind of 'hatchet man' for making enemies of the Yorks disappear. Can anyone here speak authoritatively on that claim, or can this also be chalked to Tudor propaganda?",
"I would say quite high. If you take Edward II as an example, there's a propaganda campaign in the years up to and after his death, which paint his relationship with Piers Gaveston to be homosexual and the argument here is that because he does not want what men should want, he is therefore not a man and unfit for the throne.\n\nShortly before this in Scotland you see the same with John Balliol and Robert Bruce, after Bruce's usurpation there is a campaign against Balliol that paints him as a puppet of Edward I.",
"[Everyone's interested in King Richard III! Find all the threads here...](_URL_0_)"
]
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[] |
[
"http://www.bbc.co.uk/news/uk-england-leicestershire-21083005",
"http://www.bbc.co.uk/news/uk-england-leicestershire-21063882"
] |
[
[
"http://www.youtube.com/watch?v=vYLXlbE6Ly4"
],
[],
[],
[],
[],
[],
[],
[],
[],
[
"http://www.r3.org/bookcase/croyland/index.html"
],
[],
[],
[
"http://www.reddit.com/r/AskHistorians/comments/17wa97/everyones_interested_in_king_richard_iii_find_all/"
]
] |
|
n6lc6
|
Are there any gases that can conduct eletricity?
|
askscience
|
http://www.reddit.com/r/askscience/comments/n6lc6/are_there_any_gases_that_can_conduct_eletricity/
|
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"They all do. The voltage just needs to be strong enough to overcome the dielectric between the terminals. \n\nSome of them just do it better than others. Are you familiar with neon lighting? _URL_0_",
"They all do. The voltage just needs to be strong enough to overcome the dielectric between the terminals. \n\nSome of them just do it better than others. Are you familiar with neon lighting? _URL_0_"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Neon_sign"
],
[
"http://en.wikipedia.org/wiki/Neon_sign"
]
] |
||
65vy4z
|
Is there any validity to the claim that Epsom salts "Increase the relaxing effects of a warm bath after strenuous exertion"? If so, what is the Underlying mechanism for this effect?
|
This claim is printed in wide type on this box of ES we've got & my baloney detector is tingling.
EDIT/UPDATE: Just a reminder to please remain on topic and refrain from anecdotal evidence and hearsay. If you have relevant expertise and can back up what you say with peer-reviewed literature, that's fine. Side-discussions about recreational drug use, effects on buoyancy, sensory deprivation tanks and just plain old off topic ramblings, while possibly very interesting, are being pruned off as off-topic, as per sub policy.
So far, what I'm taking of this is that there exists some literature claiming that some of the magnesium might be absorbed through the skin (thank you user /u/locused), but that whether that claim is credible or not, or whether the amounts are sufficient to have an effect is debatable or yet to be proven, as pointed out by several other users.
|
askscience
|
https://www.reddit.com/r/askscience/comments/65vy4z/is_there_any_validity_to_the_claim_that_epsom/
|
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"First I would ask what exactly are \"relaxing effects\" and how do you measure them. If they are talking about muscle pain or soreness, there is very little research and not much info on the purported mechanism.\n\nThis is a nice overview:\n\n_URL_0_",
"Probably not the primary benefit that epsom salts claim, but dissolving salts in water (or solutes into any solvent) makes the solution denser. So you're going to float slightly easier in an epsom salt batch than a normal one. Whether this makes any difference physiologically I have no idea.\n\nedit: The amount of people that made it through school without learning what a salt is is depressing me. Yes, epsom salts are salts. They are primarily a salt of magnesium, magnesium sulfate, just like table salt is a salt of sodium, sodium chloride.",
"Nobody has mentioned it, but I've always thought it had to do with magnesium, which when taken as a supplement has calming and muscle relaxing effects. I can't speak for whether it is actually absorbed through this medium, though. Can anybody elaborate on this?",
"Epsom salts are a form of magnesium. \n\nAccording to [this study](_URL_0_) it appears that magnesium is capable of being absorbed through the skin. \n\n[Here](_URL_1_) is a nice resource that may provide information regarding its (empirically-supported) efficacy and clinical uses. \n\nIn essence, the relaxing effect of magnesium appears to be due to magnesium's neurological functioning. From the examine page: \n\n > \"Low Magnesium levels are associated with neuronal hyperexcitation and random firing, and secondary to higher activation of NMDA receptors more calcium appears to be released.\"\n\nAt a rudimentary level, glutamate (what works on NMDA receptors) exerts a stimulatory function. \n\nFrom the data above, it appears that magnesium reduces the amount of glutamate that is operating in the brain when you are at a sufficient level (or optimal, really...there are issues with the RDA level as it pertains to optimal health).\n\nA study found that magnesium helped attenuate symptoms of ADHD, and that may serve as clinical support for this neural mechanism in humans. \n\nThere was further data supportive of this relaxation claim that was found in elderly people, their sleep quality increased and cortisol decreased. \n\nOverall, it's undoubtable that a comprehensive overview of how magnesium works is easily explicable. It certainly operates in myriad ways, so just know that it does. \n\nEdit: added a link to a study that found that epsom salt baths may allow for systemic magnesium to rise. ",
"When muscles contract, calcium ions are released from the sarcoplasmic reticulum (a special organelle in muscle cells) which then bind to troponin (a protein) which moves the tropomyosin off of the actin (contractile protein) allowing the myosin to bind to the actin, shortening the muscle. That's called sliding filament theory. Now, as long as there are calcium ions binding to the troponin, the muscle remains contracted. To move the calcium back into the sarcoplasmic reticulum it has to move against the pressure gradient created by diffusion. To facilitate the movement of calcium back into the SR, our cells use a protein that switches a magnesium ion for a calcium ion.\n\nEpsom salts (Magnesium Sulfate) when dissolved in water create magnesium ions. Magnesium ions are capable of entering the body through the skin (not lots but some of it does). This process is sped up by the heat of the bath increasing circulation in your capillaries. \nSource: massage therapy training\n\nNow does that mean that Epsom salts in a bath are more effective than a bath without salts? Probably. A large difference? Probably not. The heat and increased circulation are probably bigger factors in reducing soreness than the small bump of magnesium from the salts. ",
"Mg ions are needed to dissociate myosin from actin and relax a muscle after contraction. Magnesium is absorbed well transdermally, as other people mentioned I don't think a bath will be concentrated enough. I sometimes use the paste on my traps and shoulders which get funny from sleeping on my side and it works well.",
"Not sure if there is anything more recent but this was from a [review article of the literature from 2012 -Interaction of mineral salts with the skin: a literature survey International Journal of Cosmetic Science Volume 34, Issue 5, pages 416–423, October 2012](_URL_0_) \n > “The other magnesium-containing consumer product is Epsom salts (MgSO4). Epsom salt can be used internally; as a laxative, and topically in bath water to enhance skin softening and exfoliation, relieve muscle tension and to promote relaxation. Although little evidenced-based research is available in the medical literature to support these claims, mechanistically, Mg++ and Ca++ play a key role in regulating keratinocyte proliferation and differentiation and have been shown to activate keratinocyte migration, down-regulating E-cadherin and up-regulating α1β2-integrin function [20]. Denda et al.[21] studied the effects of topical application of magnesium and calcium salts on skin barrier repair in hairless mice. All of the Mg salts, except Mg bis (dihydrogen phosphate), accelerated barrier repair in this animal model. Moreover, optimum barrier repair required a Ca++ to Mg++ ratio less than unity, suggesting a complex and often antagonistic relationship between Mg++ and Ca++ in cornification. In a small human clinical study (n = 12), Schempp et al.[22] showed that topical treatment with 5% MgCl2 prior to UVB irradiation not only significantly reduced the number of Langerhan cells in the epidermis compared with NaCl, but also reduced antigen-presenting activity (mixed lymphocyte reaction) in the skin in the MgCl2-treated subjects.”\n\nMore references from the same review about dead sea salts\n\n > \"In contrast to Epsom salt, efforts to understand the medicinal benefits of bathing in saline or Dead Sea salts (balneotherapy) are substantial [23]. Interest in balneotherapy is driven by the perceived benefits of bathing in the saltiest sea in the world (320 g L−1 vs. an average 40 g L−1) that also has the highest concentration of Mg (49 g L−1) [24]. Moreover, this therapy is consistent with several modern social movements, including complementary medicine and the rediscovery of Spas for relaxation, health and well-being [25].\"\n\nReferences from above quotes\n\nBoisseau, A.-M., Donatien, P., Surlève-Bazeille, J.-E., et al. Production of epidermal sheets in a serum free culture system: a further appraisal of the role of extracellular calcium. J. Dermatol. Sci. 3, 111–120 (1992).\nCrossRef | PubMed | CAS\n21\nDenda, M., Katagiri, C., Hirao, T., Maruyama, N. and Takahashi, M. Some magnesium salts and a mixture of magnesium and calcium salts accelerate skin barrier recovery. Arch. Dermatol. Res. 291, 560–563 (1999).\nCrossRef | PubMed | CAS | Web of Science® Times Cited: 20\n22\nSchempp, C.M., Dittmar, H.C., Hummler, D., et al. Magnesium ions inhibit the antigen-presenting function of human epidermal Langerhans cells in vivo and in vitro: involvement of ATPase, HLA-DR, B7 molecules, and cytokines. J Invest Dermatol. 115, 680–686 (2000).\nCrossRef | PubMed | CAS | Web of Science® Times Cited: 17\n23\nNasermoaddeli, A. and Kagamimori, S. Balneotherapy in medicine: a review. Environ. Health Prev. Med. 10, 171–179 (2005).\nCrossRef | PubMed\n24\nCharlier, R. and Chaineux, M.-P. The healing sea: a sustainable Coastal Ocean resource: thalassotherapy. J. Coastal Res. 25, 838–856 (2009).\nCrossRef | Web of Science® Times Cited: 4\n25\nRiyaz, N. and Arakkal, F. Spa therapy in dermatology. Indian J Dermatol, Venereol Leprol. 77, 128–134 (2011).\nCrossRef | Web of Science® Times Cited: 6\n26\nHarari, M., Czarnowicki, T., Fluss, R., Ruzicka, T. and Ingber, A. Patients with early-onset psoriasis achieve better results following Dead Sea climatotherapy. J. Eur. Acad. Dermatol. Venereol. 65, 525–530 (2011).\n27\nKlein, A., Schiffner, R., Schiffner-Rohe, J., et al. A randomized clinical trial in psoriasis: synchronous balneophototherapy with bathing in Dead Sea salt solution plus narrowband UVB vs. narrowband UVB alone (TOMESA-study group). J. Eur. Acad. Dermatol. Venereol. 25, 570–578 (2011).\nWiley Online Library | PubMed | CAS | Web of Science® Times Cited: 1\n28\nHalevy, S., Giryes, H., Friger, M. and Sukenik, S. Dead sea bath salt for the treatment of psoriasis vulgaris: a double-blind controlled study. J. Eur. Acad. Dermatol. Venereol. 9, 237–242 (1997).\nWiley Online Library | Web of Science® Times Cited: 16\n29\nGambichler, T., Rapp, S., Senger, E., Altmeyer, P. and Hoffmann, K. Balneophototherapy of psoriasis: highly concentrated salt water versus tap water – a randomized, one-blind, right/left comparative study. Photodermatol. Photoimmunol. Photomed. 17, 22–25 (2001).\nWiley Online Library | PubMed | CAS | Web of Science® Times Cited: 12\n30\nBrockow, T., Schiener, R., Franke, A., Resch, K. and Peter, R. A pragmatic randomized controlled trial on the effectiveness of low concentrated saline spa water baths followed by ultraviolet B (UVB) compared to UVB only in moderate to severe psoriasis. J. Eur. Acad. Dermatol. Venereol. 21, 1027–1037 (2007).\nWiley Online Library | PubMed | CAS | Web of Science® Times Cited: 12\n31\nBrockow, T., Schiener, R., Franke, A., Resch, K. and Peter, R. A pragmatic randomized controlled trial on the effectiveness of highly concentrated saline spa water baths followed by UVB compared to UVB only in moderate to severe psoriasis. J. Altern. Complement. Med. 13, 725–732 (2007).\nCrossRef | PubMed | Web of Science® Times Cited: 10\n32\nGambichler, T., Demetriou, C., Terras, S., Bechara, F.G. and Skrygan, M. The impact of salt water soaks on biophysical and molecular parameters in psoriatic epidermis equivalents. Dermatology 223, 230–238 (2011).",
"\"Studies have shown that magnesium and sulfate are both readily absorbed through the skin, making Epsom salt baths an easy and ideal way to enjoy the associated health benefits1. Magnesium plays a number of roles in the body including regulating the activity of over 325 enzymes, reducing inflammation, helping muscle and nerve function, and helping to prevent artery hardening. Sulfates help improve the absorption of nutrients, flush toxins, and help ease migraine headaches.\"\n\nSource: _URL_0_",
"According to [this study](_URL_0_), magnesium may be transdermally used to help patients with fibromyalgia. It uses MgCl, not MgSO4, which means the anion may be what is most useful.\n\nThere are also a study published by The Nutrition Practitioner published in Spring 2010 that discusses an increase of magnesium uptake of cells through transdermal application. ",
"We're looking at a few different issues that are getting confused:\n\n1) Epsom salts are mag sulfate, which is a smooth muscle relaxant used for a variety if issues in medicine, but most commonly in Obstetrics (prevention of seizures in pre-eclampsia, management of preterm labor (which is controversial), and protecting underdeveloped fetal brains from trauma in instances of preterm delivery). This is thought to be due to competitive displacement of calcium ions by magnesium ions. It is generally used at what would otherwise be toxic levels and can also lead to respiratory inhibition as well as an overall feeling of fatigue or weakness due to similar effects on skeletal muscles. Neurologists will also use mag sulfate (IV) or mag oxide (PO) for management of migraines.\n\n2) Mag citrate is an osmotic laxative, poor GI absorption and hence used as a pre-procedure bowel prep.\n\n3) Magnesium deficiency can be associated with neurological issues, however this is mostly because of effects on potassium regulation (sorry, don't remember the mechanism). Therefore some issues like restless leg can improve in cases of magnesium replacement, however at that point you are specifically addressing a deficiency rather than benefiting from greater than normal levels. And finally:\n\n4) All of the above is mostly moot because mag sulfate has minimal topical absorption, and any actually absorbed is rapidly distributed systemically and cleared renally. But you disolve it in warm water and boy does that warm water help your feet and legs to feel better when you soak them...",
"I know I'm late to the party but I figure in case you haven't been satisfactorily answered I'd love to chip in. \n\nThe salt increases the density of the water which creates more pressure on the body so the muscles feel more worked out. Similar to the calming effects a weighted blanket has vs a non weighted. ",
"After reading this thread, I'm really saddened at the state of information in the \"information age\". Here we have a fairly widely recognized and suggested method of treatment (soaking in Epsom salts) and it's nearly impossible to walk away from this thread with any confidence in a coherent answer posted here.\n\nIf we can't even come to a consensus on freaking Epsom Salts, then how is there any hope when it comes to any topic of with even moderate conflicting information or implications?",
"I am a believer. Former football player. Plenty of swells and bruises. Epsom salt baths seemed to be marginally better at easing the pain etc. Part of what made it better was the actual viscosity and texture of the water. It made the water feel almost silky. It made for a better soak. ",
"Very long article on it\n\n_URL_0_\n\nSeems to imply no strong chemical relaxant at work (at least not through skin), however...\n\n\nSomeone below (and the article) made a good point, it's probably indirectly helping people relax as you're soaking in warm water and adding salt making you float more easily. These 2 variables together usually make people feel relaxed. \n\nHot steam treatment in particular is very effective in relieving joint/tendon inflammation, been doing that for years myself... huge relief."
]
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[] |
[] |
[
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"https://www.painscience.com/articles/epsom-salts.php"
],
[],
[],
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"http://www.epsomsaltcouncil.org/wp-content/uploads/2015/10/report_on_absorption_of_magnesium_sulfate.pdf",
"https://examine.com/supplements/magnesium/"
],
[],
[],
[
"http://onlinelibrary.wiley.com/doi/10.1111/j.1468-2494.2012.00731.x/full"
],
[
"https://www.seasalt.com/salt-101/epsom-salt-uses-benefits"
],
[
"https://www.ncbi.nlm.nih.gov/pubmed/26343101"
],
[],
[],
[],
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]
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|
26jmf3
|
why doesnt the world appear 2d if i close one eye?
|
From my understanding, depth perception and 3D vision is achieved because we have two eyes that are slightly apart, giving us slightly different vantage points. Our brain then processes the two 2D images from each eye and gives us a 3D image.
My question is: if we need two eyes to create 3D, then why doesn't the world look 2D once one eye is closed? Wouldn't we lose one part of the picture and our brains would only process the 2D image from the open eye?
Bonus question: if a person is blind in one eye, do they have poor or no depth perception?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/26jmf3/eli5_why_doesnt_the_world_appear_2d_if_i_close/
|
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"It does appear in 2d. However your brain is good at recreating the 3rd dimension by calculating parallax as you change position, as well as monitoring and comparing changes in known sizes of things.",
"Binocular depth perception only works at fairly close range. Beyond about 10m it is pretty much useless, because the views in the two eyes do not differ by enough to process.\n\nSo we use a lot of other methods for depth perception, as well. Haze, hiding of one object behind another, and perceived size of familiar objects all help us process depth. All of these work just as well with one eye as with two.",
" > depth perception and 3D vision is achieved because we have two eyes that are slightly apart\n\nAs others have said, that's partly true, but we use other cues as well.\n\nThere is quite a significant proportion of the population -- I can't remember what that proportion is, but I remember it being much higher than I would have thought -- that doesn't use binocular depth percetion at all. They can still judge distances perfectly well, and some may even be unaware of their condition until they go to see a 3D movie -- because 3D movies rely *entirely* on binocular vision to give a sense of depth. These people find that 3D movies actually look *less* 3D than normal 2D movies.",
"Your eye's lens still has to adjust and focus so you can't maintain the sense of 2D.",
"It is in 2D. Just close one eye, spread your hands, and try to touch your fingers of each hand slowly. (i.e. touch your left finger with the right finger)\n\nYour brain is just used to think in 3D...",
"In the psychology field of sensation and perception there is the concept of \"monocular\" and \"binocular\" cues. A binocular cue is something you need two eyes for to notice depth. This is pretty much controlled by your brain calculating \"how crossed\" your eyes are. If they are moving towards each other, that means the object is close, otherwise, the object is far away. It's very, very sensitive.\n\n\"Monocular cues\" refer to everything else you can use to tell depth. One is objects appearing smaller. Another is objects blocking other objects. Another is objects appearing fuzzier. Parallax is a more complicated one, but it's essentially is the fact that when you move, objects closer to you appear to move *more* than objects far you. If you're driving at night, street signs whip past you quickly, houses pass by more slowly, and the moon doesn't appear to move at all.\n\n_URL_0_",
"Try catching a tennis ball with one eye closed\n\n\nAs a streoblind person, this explained why I sucked at PE ",
"It does, but your brain is clever fucker. He will make it so it seem 3D. Try to judge distance with 1 eye closed. Yeah it doesnt go that well."
]
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[],
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|
373mn0
|
why is two-x chromosomes a default sub?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/373mn0/eli5_why_is_twox_chromosomes_a_default_sub/
|
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"text": [
"The default subs are based on popularity, which is based on how many members they have and how many people view them. They just happen to be the most popular subs, for whatever reason.",
"Whatever group of people that are responsible for choosing it considers it to be an important sub. It's likely that the sub is there for the sake of offsetting the stereotype that reddit is a male-driven, anti-feminist place and make reddit seem more inclusive for women. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
bh61ri
|
how long could an umbilical cord stay attached and would it give any benefits?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bh61ri/eli5_how_long_could_an_umbilical_cord_stay/
|
{
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"The umbilical cord should fall off after about 1-3 weeks. If it doesn't, it could be a sign of infection or an immune system disorder. This is because the baby's body has a white blood cell called a neutrophil whose job is cut off the umbilical cord so it falls off. If there is an immune system problem, there are no neutrophils to cut off the umbilical cord. If there is an infection, the neutrophils are busy fighting the bacteria and don't have time to cut off the umbilical cord. \n\nThere are no benefits to the umbilical cord in a baby after birth. The whole point was to transfer food and oxygen from the mother to the baby while it was in the womb. Once it can eat food and breathe on its own, the umbilical cord doesn't do anything anymore."
]
}
|
[] |
[] |
[
[]
] |
||
4u9eua
|
what are the dark bruises under a person's eyes that appears when they're tired?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4u9eua/eli5_what_are_the_dark_bruises_under_a_persons/
|
{
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"text": [
"When you're tired, the body releases a hormone called cortisol to boost energy levels, cortisol increases blood flow in the body.\n\nThe skin around a persons eye is a lot thinner than the rest of the body, so all the dark patches are is the blood vessels showing underneath the skin. It is more noticeable when tired due to the extra blood flow (vessels expand)"
]
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|
[] |
[] |
[
[]
] |
||
2i4gm8
|
Why do food labels say you shouldn't microwave raw chicken?
|
I don't quite understand how an oven can cook raw chicken but a microwave can't.
|
askscience
|
http://www.reddit.com/r/askscience/comments/2i4gm8/why_do_food_labels_say_you_shouldnt_microwave_raw/
|
{
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"Microwave ovens don't heat very evenly, as anyone who has tried to eat a Hot Pocket can tell you. So when microwaving a large piece of chicken, there is a fairly high chance that spots within the chicken will be undercooked, and therefore at a higher risk of spreading food-borne illness. Regular ovens heat uniformly and provide a much more predictable method of heating the meat all the way through.\n\nThat said, there are a few ways around this. Small pieces of chicken (less than 1\") are more likely to cook evenly. You can also use a second heating medium by using a microwave steamer (reusable, or the disposable bags) to steam the chicken inside the oven. This provides an external heat source to help even out the heat transmission into the chicken, rather than relying on inconsistent internal heating."
]
}
|
[] |
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[
[]
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|
88p0jk
|
Anti-Semitism in 1942-1945 Nazi Germany Propaganda
|
I was wondering if it is true that anti-semitic propaganda became increasingly common after the fall of Stalingrad and when defeat was becoming increasingly plausible. If this was the case, I was wondering why that may be the case and if this had any effect on the public. Furthermore, were there any other recurring themes in German propaganda that were prominent nearing the end of the war?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/88p0jk/antisemitism_in_19421945_nazi_germany_propaganda/
|
{
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"Modified from an [earlier answer of mine](_URL_0_) \n\n > Enjoy the war, for the peace is going to be terrible- popular German joke in the last year of the war\n\nAs the fortunes of war turned against Germany after the Battle of Stalingrad, German propaganda found an imperative need to readjust to this new reality. Prior to the military reversals of 1942, German propaganda had operated on the principle of presenting an \"ersatz reality,\" wherein the state-dominated media maximized Germany's victories and ignored the salient reality that Germany's war was not a short one and her enemies persisted in fighting Germany. The scale of defeats like Stalingrad, the growing Allied bombers, and the surrender of German forces in North Africa pricked this media bubble and German propaganda organs responded accordingly. \n\nThis retooling of the Third Reich's propaganda apparatus in light of defeat pursued several seemingly counter-intuitive strategies. For one thing, despite the fact that the Third Reich was a personalist dictatorship *par excellence*, the figure of Hitler disappeared from German propaganda. In contrast to propaganda from the earlier years of victory, post-Stalingrad news of German military operations seldom invoked Hitler's name or connected him too heavily to military operations. This was part of a deliberate strategy on Goebbels's part as he recognized connecting Hitler too intimately to Germany's military fortunes made him, and by extension, the legitimacy of the entire regime, culpable when these operations did not bear fruit. Rather than present images of the Führer, Hitler was invoked in late war propaganda as an abstract figure that stood for all Germans. This could just be from invoking his title, or oblique historical analogies such as films that made apparent the connection between Hitler and historical personages like Frederick the Great. Hitler, whose visage was omnipresent in state propaganda between 1933-1941, became an abstraction. By the same token, German propaganda also emphasized the severity and violence of German military setbacks, but with a unique spin. Allied bombing, the Soviet massacres of Polish officers at Katyn, and other actions of the Allies became staples of German propaganda after the tide had turned as it showed that Germany's enemies were merciless. This [poster](_URL_2_) of the Katyn massacre does not shy away from either blood or the gruesome faces of the NKVD officers. The idea behind this emphasis upon the Allies' purported barbarity was to bind the Germans together through a policy of \"strength through terror.\" This dehumanization of the Allies' military underscored that no compromise was possible and this was a war in which there was to be no quarter given and none expected. \n\nThese new strategies often dovetailed with established propaganda discourses that had been present within the Third Reich since 1933. The regime's castigation of the so-called \"November Criminals\" of 1918 also found new currency in this environment. Interrogations of German troops captured after 20 July 1944 often reported back that one key motivation for fighting on was to prevent a repeat of Germany's humiliating defeat at the end of the First World War. One important component of the demonization of the Allied military was that German retribution was in the making. Since 1933, one of the central legitimizing planks of the NSDAP was that it had enabled German technology and genius. The vaunted V-weapons tapped into this established narrative that German technical expertise brooked no rivals. But beyond rockets and other *Wunderwaffen*, National Socialism had always stressed the ability of the will to transcend any material obstacles. This propaganda's emphasis upon collective action in the face of numerical superiority fed into this notion that the will is superior to rational logic. Similarly, the destruction of German landmarks and the seemingly indiscriminate nature of Allied bombing heightened the sense that this was a cultural war and that the Germanic culture constantly trumpeted by the Third Reich was in existential danger. \n\nOne sinister aspect of the late war propaganda was its turn to a heightened antisemitism. Goebbels used the solidarity of Allied coalition of both the imperial Britain, hypercapitalist United States, and the Bolshevik USSR as evidence of grand global Jewish conspiracy against Germany. This [infamous poster](_URL_1_) was only one example of this propaganda line that a single Jewish force was holding together a coalition against Germany. Victor Klemperer in his diaries would note the increasingly shrill antisemitism in propaganda as Germany's fortunes waned. The widespread knowledge about the Holocaust amongst the German public imparted a weight to this propaganda that it might not have otherwise possessed. Although they might not have known the specifics of the Holocaust, most Germans were aware that something quite terrible had happened to the Jews in the East. Even though the antisemitism was troweled on so thick to strain credibility in this propaganda, it encouraged the expectation that the Allies would hold Germany collectively responsible for the mass murder of the Jews. This does not mean that the German public accepted the NSDAP and Propaganda Ministry's antisemitism wholesale, but in some cases Germans interpreted antisemitism quite differently than the state. One popular rumor among German civilians in 1943/4 was that Hungary had not been the target of any Allied bombings was because the Hungarian government had spared its Jews. The SD recorded a number of complaints that because the Horthy government has ghettoized Jews in Budapest the Allies would not attack this human shield, and there was grumbling within the German populace that Hitler did not do the same for cities like Berlin or Hamburg. And some of this disgruntlement was not clandestine, but took the form of direct petitions to Goebbels. There were a string of letters to the Propaganda Ministry after the mass operations to clear Hungary's Jews in 1944 demanding that they be used as human hostages against Allied bombing. But the general acceptance of some of the antisemitism produced by Goebbels's machine precluded thought of or even the possibility of a negotiated peace for much of the German public. News of the Morgenthau Plan, which would have deindustrialized Germany, the expansion of Allied bombing, and the scale of German reverses fostered a general expectation of a Carthaginian peace. \n\nThe effectiveness of this late-war propaganda is open to interpretation. While it could not rekindle hope in final victory, it did strengthen the resolve of some Germans to see the war to its bitter conclusion. Yet, even as propaganda turned to negative integration (uniting around a threat), it could not arrest the gradual estrangement of much of the German public to the National Socialist state. Goebbels himself appreciated this sentiment and his famous February 1943 *Sportpalast* speech had veiled threats against the \"Golden Pheasants\" of the NSDAP who were thus far still enjoying a prewar lifestyle. This late-war propaganda often worked in conjunction with greater arbitrary state violence directed against Germans, especially after the 20 July plot. The propaganda drive for mass action and a collective response to Allied aggression heightened the sense of social anomie and the breakdown of society that came as bombing and wartime pressures destroyed the German infrastructure and stretched the civilian domestic economy well past its breaking point. The final agonies of the last few months of the war, as well as the violence meted out to Germans that shirked in their duties, helped to cement the postwar myth that Germans were double victims of the war- who were both subject to extreme violence from their military enemies, but also brutalized by a hypocritical criminal regime. \n\n*Sources*\n\nKershaw, Ian. *The 'Hitler Myth': Image and Reality in the Third Reich*. Oxford: Oxford University Press, 2001. \n\n_. *The End: The Defiance and Destruction of Hitler's Germany, 1944-1945*. New York: Penguin Press, 2011. \n\nMilitärgeschichtliches Forschungsamt. *Germany and the Second World War, Volume IX/1: German Wartime Society- Politicization, Disintegration, and the Struggle for Survival* Oxford: Clarendon Press, 2008. \n\n_.*Germany and the Second World War, Volume IX/2: German Wartime Society- Exploitation, Interpretation, Exclusion* Oxford: Clarendon Press, 2014. "
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/3g64o0/how_did_the_nazi_propaganda_machine_spin_germanys/?limit=500#ctvf772",
"https://www.ushmm.org/information/press/press-kits/traveling-exhibitions/state-of-deception/behind-the-enemy-powers-the-jew",
"https://www.kunstkopie.de/kunst/unbekannter_kuenstler/massaker_von_katyn_ns_propagan.jpg"
]
] |
|
605u59
|
what does it mean to be "red pilled?"
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/605u59/eli5what_does_it_mean_to_be_red_pilled/
|
{
"a_id": [
"df3oev3"
],
"score": [
14
],
"text": [
"In the film *The Matrix*, the main character is offered a red pill that (indirectly) allows him to perceive the world as it really is for the first time (the alternative blue pill would have let him keep his illusions and never find out the truth).\n\nIn internet talk, people who have adopted controversial, non-mainstream beliefs use the analogy to imply that they have \"woken up\" to the real facts, and that everyone who doesn't agree with them is asleep. Most famously the term is used by Men's Rights Activists or MRAs who claim to have realised that, actually, men are more oppressed than women. The term tends to be associated with conspiracy theories and reactionary right wing causes."
]
}
|
[] |
[] |
[
[]
] |
||
2hn0l2
|
why can i drink flavored drinks until i'm stick, but i struggle to drink the equivalent of water.
|
I try to drink a gallon+ of water each day and its a struggle to do so, but if I add some flavoring to the water I can drink a gallon+ easy.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2hn0l2/eli5why_can_i_drink_flavored_drinks_until_im/
|
{
"a_id": [
"cku5nz1"
],
"score": [
2
],
"text": [
"A gallon of water a day? That seems like a hell of a lot quite frankly and unless your doing some heavy work outs I doubt you need that much. Actually that's related to why you cant drink much. Water doesn't really have much of a taste But since it's not for the taste you drink it purely to quench your thirst and that doesn't take much honestly unless your sweating a ton which would only happen if it were really hot or of course exercise."
]
}
|
[] |
[] |
[
[]
] |
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