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3hvmv4
|
If the stereotypical European knight were to have a duel with the stereotypical samurai, what would they both bring to the fight equipment wise? (Not a who would win)
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/3hvmv4/if_the_stereotypical_european_knight_were_to_have/
|
{
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"text": [
"Your question is somewhat too broad to really be answered. Over the hundreds of years, throughout many different kingdoms in Europe and different periods in Japan the equipment would change drastically. Sometimes pole arms, sometimes swords, sometimes bows, even axes or hammers could be typical in certain areas or times. Also the armor would change greatly... You probably should pick a specific European Kingdom and a more specific time period then resubmit the question to get a better answer. "
]
}
|
[] |
[] |
[
[]
] |
||
31m72d
|
economically speaking is there an optimum population level where almost all citizens have a high standard of living?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/31m72d/eli5_economically_speaking_is_there_an_optimum/
|
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"The ideal political structure you're thinking of is communism. Everyone works for everyone and the greater good of society, as well as being classless so no one is better than anyone",
"Modern socialist countries come close. Really, it's a matter of technology and infrastructure - Communism is practically impossible because of the massive administrative costs, bureaucracy, and logistics - all of which are aided significantly by modern information technology, which is why socialism is working, because it's sort of a compromise between private ownership/business versus government ownership/business.\nIf we ever get to Star Trek-level technology with fusion power, replicators, and teleportation, getting food to the needy will be practically free and effortless, which is why in Star Trek no one starves. The only reason people starve now is that it costs money and takes time to move food (plus the people who have it have to be willing to share)."
]
}
|
[] |
[] |
[
[],
[]
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||
z5skk
|
During the cold war, did Britain play much of a part in the hostilities?
|
What were the chances that if the nukes started falling Britain would have been in the firing line? Or would it have come down mostly to the USA and USSR taking the punches?
Edit: Also, why was it called a War if no one actually died?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/z5skk/during_the_cold_war_did_britain_play_much_of_a/
|
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"In a full blown nuclear exchange, the USSR would have bombed all NATO states (UK included) and NATO would have bombed all Warsaw Pact states. But these aren't the only people who would be affected. In the post-exchange aftermath, the great powers will be severely weakened and will be vulnerable to any lesser but still powerful state. These countries would have to be preemptively bombed as well to safeguard your own security. The USSR had plans to bomb the Chinese (the Chinese did lose Outer Manchuria to Russia only about 150 years ago); the Chinese knew this and the USSR knew that the Chinese knew this. Moreover, the Russians (not USSR) had plans to bomb their own allies in the worst case scenarios. There are several other countries not mentioned but everyone would have been affected. \n\nDuring the Cold War, there were (and still are) several major think tanks that devoted their existence to analyzing various nuclear war scenarios. [Herman Kahn](_URL_0_) was one of the most well known figures.",
" > Also, why was it called a War if no one actually died?\n\nThat's... probably not entirely accurate.",
" > Also, why was it called a War if no one actually died?\n\n\nMany people *did* die during the Cold War as a direct result of the Cold War. The term is sort of a blanket term for a lot of different events that occurred during the relevant time period. It's sort of, but not exactly, like how the term \"World War II\" encompasses lots of related conflicts.\n\nThere were quite a few military actions during the course of the Cold War that were basically proxy wars for the USA/NATO and USSR/Warsaw Pact. [See here for a brief overview of such examples.](_URL_0_) Neither side could risk full on open warfare against each other, but they still sought to weaken each other, and weaken their opponent's sphere of influence, allies, etc. ",
"Great Britain was very much a part of the Cold War, which was, let's remember, basically a balance-of-power struggle between the Warsaw Pact nations (a fake 'alliance' between the USSR and the other soviet puppet states) and NATO. Russia knew that if it started slinging missiles it would have to reckon with the USA very quickly; but in any ground war, Russia also knew that it would first have to deal with West Germany, France, Italy and Great Britain, as well as those US forces on the ground in Germany.\n\nIt was called a 'cold war' because it was a life-and-death struggle that involved a great deal of killing, blackmail, military and political struggle ... but pretended not to be a war at all because actual armies weren't clashing. There was no word or phrase for such a state of affairs prior to this in history. The phrase was originated by George Orwell in an essay written in 1945, but it was popularized by Bernard Baruch, an American presidential advisor, in a speech he gave in 1947, where he said:\n\n\"Let us not be deceived; we are, today, in the midst of a cold war.\"\n\nThe term can be seen, then, as a wake-up call when it was first used, to jar the public into realizing that the wartime alliance between the West and the Soviet Union was over. ",
"Britain was seen as a vital part of the nuclear coverage of NATO, as it had operable nuclear submarines which generally could extend the reach of ~~America's~~ NATO's missile range, along with France, which many people often forget as having the third most nuclear missiles than any other country, and are to blame for the parts of the South Pacific being a radioactive hellscape.\n\nAlso the Falklands War was a significant part of the Cold War era, as it was said the Russians looked on in great interest as one of America's allies was putting put to the test as it were, as a bench mark of NATO readiness; They passed with flying success. The same could not be said of the WARSAW pact states, which were largely just pressured into Soviet obedience, and were likely to just run for the bunkers when anything got too real for them. It may well have been this conflict that could have hastened the collapse of the Berlin Wall, as if NATO was proven to be willing to fight, then the risk of the meat grinder in Central Europe becoming all too messy becomes much more of a factor in military, and diplomatic, decisions.\n\nIt is most important to remmember that Europe is tightly packed, and any blast in East Germany would certainly have fallout effects over much of the West, including Britain, based on prevailing winds. The whole world would never have recovered from any such nuclear winter, hence why no side would ever likely have done so.",
"Britain had a nuclear strike capability. The V-Bombers, and later SLBMs.\n\nUSAF aircraft based in Britain engaged in spy flights, as well as maintaining a nuclear strike capability.\n\nIn the 1950s and early 60s Britain secured the Persian Gulf.\n\nBritain also flew spy flights over the Soviet Union."
]
}
|
[] |
[] |
[
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"http://en.wikipedia.org/wiki/Herman_Kahn"
],
[],
[
"http://en.wikipedia.org/wiki/Proxy_war#Cold_War"
],
[],
[],
[]
] |
|
2xezog
|
Since astronomers have found mega-stars that are millions of times larger than the Sun, is it possible to have mega-planets that are millions of times larger than the Earth?
|
_URL_0_
After watching this video showing the progression of stars and their sizes, it first made me thought how small we are. The Sun is the largest object in the Solar System, but in comparison to supermassive star, the Sun is *barely* *a* *pixel* (never mind the Earth!). I was wondering whether it's possible to have planets that are this huge in comparison to the Earth that are orbiting these mega stars? Maybe not rocky planets but massive gas giants?
Cheers Reddit
|
askscience
|
http://www.reddit.com/r/askscience/comments/2xezog/since_astronomers_have_found_megastars_that_are/
|
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"There are planets bigger than earth and even larger than jupiter, but not that much larger like those hypergiant stars compared to our sun. \n\nThere is an equilibrium between different forces, that counteract each other. The graviatation for example pulls matter inwards, and shrinks the size of an object. Degeneracy prassure or radiation pressure counteract them and stop the contraction at one point. \n\nVery massive and/or very evolved stars have a huge radiation pressure, which counteracts its own gravity and expands the star. The reason for this is, that in such stars the nuclear reaction runs at a much faster pace than in normal main sequence stars. Therefore, their hydrostatical equlibrium is reached at a much bigger size. \n\nPlanets don't have have radiation pressure. They don't run nuclear fusion and have to completely rely on their electron degeneracy pressure. The thing here is, you can't add matter like you want to increase the size. Instead, at some point the planet will shrink, so the planet becomes more dense when gaining mass. \n\nJupiter sized planets are pretty much the upper end of this. Adding more mass will make the planet become smaller. But there something that can make planets grow in size: heat from an outside source. If the planet is orbiting very closely to a star, the heat can expand the planet's gaseous hull and let it grow. One example for this is [TrES-4b](_URL_0_), which is the largest known planet at the moment. It's slightly less massive than jupiter but much bigger in size. \n\nJust as a side note to prevent confusion: When astronomers call about the size of the star, they are actually talking about its mass, because the actual size isn't that important for how a star evolves. ",
"Well, the simple answer is to compare the Earth to Jupiter. We know the mass of Jupiter is about 300x the Earth's, and its radius is about 10-11x. So there's a baseline.\n\nNow, to get a good idea of the ceiling, we can look at Jupiter and compare it to what we know about other stellar objects. The biggest objects we know of that aren't \"real\" stars are brown dwarfs (tolkien prefered \"dwarves\"). A brown dwarf is ~80x the mass of Jupiter (I have no hard evidence of radius comparisons).\n\nSo, if Jupiter is about 300x the mass of Earth, and brown dwarfs are roughly 80x the mass of Jupiter, we can determine that there are sub-stellar objects that are about 24000x the size of earth. Above that and hydrogen fusion kicks in, making your object a star."
]
}
|
[] |
[
"https://www.youtube.com/watch?v=HEheh1BH34Q"
] |
[
[
"http://en.wikipedia.org/wiki/TrES-4b"
],
[]
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|
7fv8we
|
What combinations of frequencies and harmonics do musical instruments create?
|
I'm currently writing a physics essay about frequencies of notes and chords. For the experimental part of the essay, I'm analysing the frequencies produced by said notes and chords with a Fast Fourier Transform. When playing an A4 note, for example, I see all the harmonics of the A note, as expected. However, I'm also seeing a bunch of frequencies belonging to completely different notes. [Here's a picture.](_URL_0_) How can this be explained?
It is possible that I'm analysing the FFT data completely wrong, so keep that in mind.
|
askscience
|
https://www.reddit.com/r/askscience/comments/7fv8we/what_combinations_of_frequencies_and_harmonics_do/
|
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" > When playing an A4 note\n\nAre you playing it on an instrument? Or is it a perfect sine wave? \n\nIf it's not a perfect sine wave the shape of the wave will affect the harmonics. Take a look at the [Fourier series](_URL_0_)\n\nAny wave can be made up by the infinite sum of simple sine waves. A square wave, for example, will introduce odd integer harmonics. A saw tooth will introduce all integer harmonics.\n\nIf this is an instrument, the quality of the shape of the wave is called [timbre](_URL_1_). It's the reason a piano sounds different than a clarinet, and a trumpet different than an oboe, even though they might be playing the same pitched note.\n\nThe timbre of the instrument will introduce some interesting harmonics, because the difference from a regular sine wave is made up of an \"infinite\" series of smaller sine waves all varying in frequency.\n\nAn interesting bit, in my opinion, is that when you overdrive an electric guitar, it makes the waves more like square waves. Which introduces odd harmonics. Changing the harmonics changes the sound, meaning normal chords don't sound as good, so they have a set of \"power chords\" that sound great with distortion caused by overdriving, but don't sound the best on their own."
]
}
|
[] |
[
"https://i.imgur.com/z4t0EId.png"
] |
[
[
"https://en.m.wikipedia.org/wiki/Fourier_series",
"https://en.m.wikipedia.org/wiki/Timbre"
]
] |
|
1hrv3h
|
Out of all the various religions in history, what made the major ones of today catch on?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1hrv3h/out_of_all_the_various_religions_in_history_what/
|
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"There really is no answer to this question. However, it appears that changing technology, migrations and political realities made particular types of religions and particular governmental systems more common and seemingly more efficient and useful. For example, we see an almost universal shift to Monotheistic Absolute Monarchies during late antiquity and much of the historical record tells us that people saw monarchy and monotheism as the teleological perfection of systemized rule and society, almost in the same manner that people see free market capitalism and democracy today.\n\nOf course, it changes from place to place and there are many exceptions but patterns and trends do exist. ",
"To some extent, it was because some of the big modern religions (Christianity, Islam, Buddhism) put huge effort and resources into missionary work and evangelism. This is actually something of a novel concept in belief, which for most of human history has been more related to what the king or whatever tribe you were in believed. By actively seeking converts, these religions could expand beyond the political control of their adherents, like how Ireland became Christian before ever being conquered by another Christian power."
]
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|
[] |
[] |
[
[],
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||
1ybt1w
|
How do lifeforms without some kind of cognition perform what appears to be goal-oriented behavior?
|
I'm not quite sure how to put this into words, so I'll give an example. [This video](_URL_0_) has been on reddit plenty of times before, showing a white blood cell "chasing" a bacterium. How does it know where to go? Does the bacterium leave some kind of chemical marker that the white blood cell picks up, and the white blood cell is just chemically "programmed" to move towards the marker?
Also, for bacteria and other single cells, how do they perform their basic functions? I'm sure bacteria need to find some kind of sustenance and reproduce. How do they "decide" to do these things and when? I've learned about things like the processes of mitosis and fission for cell reproduction and the various stages of each, but what prompts the processes to begin?
Is there some kind of dividing line where cognition becomes distinguishable from processes approximating/simulating it?
This may be too broad a question for a reasonable answer or flat out asked incorrectly. My apologies for any misunderstandings in this post (I'm a computer engineer, not a biologist).
|
askscience
|
http://www.reddit.com/r/askscience/comments/1ybt1w/how_do_lifeforms_without_some_kind_of_cognition/
|
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"You're hinting around two of my favorite topics when you talk about bacterial decision making and have forced me to open my dissertation =P.\n\nI can't help you with the white blood cell thing, if I hazard a guess I'd say its a chemoattractant gradient but that's a total guess. But! I can help you with the bacterial questions!\n\nThere are some behaviors that are not advantageous (or downright harmful) for a bacteria to do by itself or when very few of them are around but are very desirable when many of the them are around. One example of this is causing an infection. This is why we have things called a **minimum infectious dose**, you need X number of bacteria in order to cause an infection (this number is different for each organism). That's because the bacteria do indeed communicate with each other through a process called **quorum sensing**. Essentially, the bacteria need to reach a certain concentration (cells/space), or *quorum* to change their behavior. Most changes in behavior on a bacterial level boil down to what genes the bacteria is expressing. The same way congress has to meet quorum to vote, bacteria need to meet quorum to change what genes they express. \n\nThe bacteria communicate with each other by producing a chemical signal, called an **auto-inducer**, I'll call it an AI from here on. This is usually a peptide (small protein) or a sugar molecule, depending on which bacteria we're talking about. This AI is freely diffusible, so it crosses the bacteria's membrane without any assistance. Each bacteria also produces a specific protein that can bind the AI called a **response regulator** (RR). The chances of the AI encountering the RR are purely probabilistic, hence the more AI you have the better the chance of an AI encountering an RR. How do you get more AI? You have more bacteria in the space. As the bacterial population increases and the amount of AI increases more RR will be interacting with AI, eventually this reaches a level where the RR/AI complex is able to change gene expression, this is when the cells have reached quorum. RR/AI will turn some genes off and others on, or it may make genes that were already turned on be even *more* active. By doing this the behavior of the bacteria will change. For example, the bacteria *Yersinia enterocolitica* uses quorum sensing to control its motility, *Pseudomonas aeruginosa* (and many others) use quorum sensing to turn on genes allowing biofilm formation and virulence and *Salmonella enterica* eaves drops on other bacteria's quorum sensing communication by intercepting their AI and using it to active its own RR to turn on genes that let it take up free DNA in the environment. \n\nAs far as bacteria finding food, a lot of the bacteria use motility and **chemotaxis** for this. Chemotaxis is pretty complicated but here's the process, basically. A bacteria will move in a random direction, in classical chemotaxis the movement is mediated by flagella in a form of motility we call swimming. The flagella is like a propeller, if it turns in a counterclockwise (CCW) direction the bacteria moves forward, we call this running. If the flagella turns in a clockwise (CW) direction the bacteria spins around, we call this tumbling. After a tumble the bacteria will start running in a new, random direction. Whether a flagella rotates CCW or CW is based the the modification of a protein on the inside of the cell that is responsible for turning the flagella. Over time, this protein accrues the modification (which is mediated by two other proteins) that lead to tumbling, these modifications will be accrued more slowly if the bacteria are moving up a chemical gradient toward food and will accrue more quickly if the bacteria is moving either towards something toxic or down the food gradient. Even if the bacteria is moving up the food gradient eventually the cell will tumble. This is because, as more modifications build up on the protein that turns the flagella, it becomes less able to sense small changes in the chemical gradient. Eventually the protein is forced to turn the other direction, causing the tumble, in order to reset its modification levels and be able to sense again. The chemotaxis article on wikipedia is actually really good, but may be more than you want/need to know: _URL_0_\n\nAs far as the day to day maintenance, like cell division, these are time cycles usually. There's a series of steps, like you mentioned with mitosis, and each step has check points that are mediated at the molecular level. The cell won't (shouldn't, actually, things can go wrong) divide if the chromosomes aren't at separate poles, it detects this with a protein that sends a signal that allows the process to go to the next step. Its a lot like a computer program actually, its certainly not intelligent, but it functions within a set of parameters and if you put it in a different parameter you don't really know what it'll do. A Cellular Biologist should be able to give you a better explanation of what starts and stops cell division than I can."
]
}
|
[] |
[
"http://www.youtube.com/watch?v=JnlULOjUhSQ"
] |
[
[
"http://en.wikipedia.org/wiki/Chemotaxis"
]
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|
gdcpo
|
If we were to find life on an alien planet, would it have DNA structured the same at all?
|
I don't understand much about DNA or biology, so forgive me, but I've always been intrigued by the concept. All life on Earth seems to have some genetic code structured in the same way, but is that because we all came from a common ancestor or because that's just how life evolves? If we were to go to a different planet, light years away, and found some unintelligent life, would they have DNA in the same same double helix, GATC structure?
|
askscience
|
http://www.reddit.com/r/askscience/comments/gdcpo/if_we_were_to_find_life_on_an_alien_planet_would/
|
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"Our genetic code is all the same because we evolved from a common ancestor, as you say.\n\nWe just don't know what other molecules might be able to serve as genetic material. It might or might not be that life evolving in Earth-like conditions tends to end up with DNA (or something very very similar). It could be that DNA is the only thing that works well, or it might turn out that something else can do the job.\n\nAny life that evolved in non earth-like conditions would be quite different - maybe silicon instead of carbon, or ammonia instead of water. That kind of life obviously wouldn't use DNA.\n\nIf alien life did use DNA, it would likely have the same double helix structure. It might not use the same four bases (G, A, T and C) - there are other choices which might be equally valid. I don't know much about the other bases - it's possible that it might not be a 4-letter code; aliens might use a different number of bases.\n\nAs for the genetic code (the way three DNA bases specify one amino acid in a protein), this would probably be entirely different.",
"Life on Earth all has the same fundamental genetic machinery primarily because all life on Earth shares a common ancestor. Nevertheless, it stands to reason that during the early evolutionary history of life on Earth there were competing systems of life and there are some underlying advantages to the system that survived. The question is which elements of our genetic machinery are more or less arbitrary conventions and which are more fundamental advantages.\n\nWithout trying to invent a set of entirely novel systems from scratch what we can do is look at each part of our own systems and see which are more fundamental and which are more arbitrary. At the highest level the basic concept of storing genetic code in something very DNA like which translates into a string of amino-acids that make up a protein is likely to be universal enough to at least see multiple examples independently evolve out in the universe. It's too slick of a system and the precursor elements are quite prevalent in the environment. The specific amini-acids used for proteins are variable even amongst various Earth-based life so there's likely to be a considerable variation with alien species.\n\nInterestingly, there are a lot of good reasons why RNA (with GAUC bases) may be a fairly likely fundamental component of early life forms, and the reasons for the slight modifications to RNA to make it DNA (changing Uracil to Thymine, for example) are sufficiently straightforward, simple, and necessary (reduced mutation rate from using Thymine, for example, ability to form a double helix w/ DNA etc.) So it's possible that independently evolved organisms out there in the Universe also have DNA.\n\nThe specific code for translating nucleotide bases to amino-acids is almost certainly going to be quite different, perhaps even radically so, for other organisms.\n\nBeyond that, it's hard to say, because so much of the machinery of life is dependent on its evolutionary history. Overall I think I wouldn't be too surprised to see something very much like DNA and proteins in alien life forms."
]
}
|
[] |
[] |
[
[],
[]
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|
2atir1
|
how can stars like vy canis majoris, betelgeuse, and rho cassiopeiae be so large without collapsing upon their own gravity?
|
I originally submitted this as a comment and decided to take it to the next level.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2atir1/eli5_how_can_stars_like_vy_canis_majoris/
|
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"They are held at bay by the **cataclysmic** heat of nuclear fusion. When that runs out, when it starts fusing iron and can't keep generating heat at the fusing edge of the core it goes poof and forms a neutron star or black hole. The sudden collapse ejects an amount of energy that is difficult to imagine and you see a supernova.\n\nLogic says that if rate of fusion is proportional to the pressure, then larger stars die faster. And they do.\n\nOur sun has existed for > 4bil years. Something like VY Canis would likely die in under a few hundred million."
]
}
|
[] |
[] |
[
[]
] |
|
3pmfkc
|
Did people ever believe that humans couldn't exceed a specific speed?
|
This is specifically for british culture, I guess. There are quite a lot of references to the idea in victorian stories (e.g the introductory scene in 'Around the world in eighty days' etc.).
Basically, was it ever actually common belief that exceeding a specific speed would be fatal, or is it just an urban myth?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3pmfkc/did_people_ever_believe_that_humans_couldnt/
|
{
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"I'm having an impossible time finding a source for this, but when the train was first invented/becoming common, especially in the UK, there were urban legends that the speed of the train (even being inside of it) was too fast for humans to tolerate and could cause seizures, make it impossible to breathe, and even permanently damage your eyes because they wouldn't be able to adjust to the fast motion, although this was kind of the anti-vaxxers of the day, and not most people dismissed them as being ridiculous.",
"Yes a popular english 'science' writer Dr Dionysius Lardner in the 1820s and 1830s wrote that humans would find it difficult to breath at speeds above 30mph.\nFurthermore he thought eyesight would be damaged by the eyes trying to focus on scenery as it passed too quickly.\n"
]
}
|
[] |
[] |
[
[],
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|
1z747w
|
why do i get billed a much higher amount for medical services/prescriptions than my insurance company?
|
If I buy my prescription outright, it costs me $450. Through insurance, they bill $221. It's the same medication in the same exact quantity.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1z747w/eli5_why_do_i_get_billed_a_much_higher_amount_for/
|
{
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"text": [
"Because people tend to go to medical facilities that accept their insurance provider (so they can actually *use* their insurance). The insurance companies negotiate discounts on services in exchange for allowing the facility to accept their insurance. It's in their best interest to make the deals with the insurance companies so they don't lose out on the business of all of the people who use that provider."
]
}
|
[] |
[] |
[
[]
] |
|
3u0otj
|
Found this carved into my basement wall under an old layer of white wash. My house was constructed in 1861, anyone have any idea of its meaning?
|
My dad thinks it may have something to do with the underground railroad for some reason. I live in the Hudson Valley in New York. So some of the letters are hard to make out, and i would have to rip up more white wash to reveal more, but some of the letters were crumbling. Here is the link: [Imgur](_URL_0_)
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3u0otj/found_this_carved_into_my_basement_wall_under_an/
|
{
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"text": [
"Can you post another photo or two so the symbols are clearer? Alternately, highlight or draw them since you can see them better in person.\n\nAlso, have you spoken with your local historical society? They may be able to both assist in finding out the owners or heritage of the home itself, which could shed quite a bit of light on the subject. Many have extensive maps and records of individual homes, fire insurance maps, parcel maps, etc. I'd venture a guess that they'd be quite interested in it!",
"There is a brick collecting club focused on the Hudson Valley, whose members specialize in identifying marks on old bricks. It may be worth getting in contact with them over at [their website](_URL_0_). Now, yours is hand-carved rather than a maker's mark, but if anybody is familiar with it, those folks are likely to be."
]
}
|
[] |
[
"http://i.imgur.com/wrzbXKo.jpg"
] |
[
[],
[
"http://brickcollecting.com/"
]
] |
|
t06wp
|
Why is the globe always shown one way? (Hard to explain my question, more info inside)
|
askscience
|
http://www.reddit.com/r/askscience/comments/t06wp/why_is_the_globe_always_shown_one_way_hard_to/
|
{
"a_id": [
"c4iff39",
"c4ifhib",
"c4iflfd",
"c4iidls"
],
"score": [
7,
4,
5,
2
],
"text": [
"It's just a convention that has persisted since antiquity. To quote [Wikipedia](_URL_0_):\n\n > The convention that North is at the top (and East at the right) on most modern maps was established by the astronomer Ptolemy and was adopted by other cartographers.",
"yes they could have mapped it like that. the reason it mapped with north as up is based on historic, political and cultural pressure.\n\nIn fact, maps have occur drawn this way before.\nOther maps show the the split in east-west in different locations, and even a map based on observation such that it is a long scroll.",
"Many medieval maps were drawn with East at the top (eg _URL_0_). In earth sciences we regularly use different projections - for example polar projections. The Mercator-type NESW projection is a result of centuries of European exploration dominating the map-making insdutries. There's no fundamental reason it couldn't be drawn with any other orientation. ",
"Consider that if you are making a globe, how is the easiest way to see most of the areas the western world will be most interested in?"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Reversed_map"
],
[],
[
"http://www.herefordcathedral.org/visit-us/mappa-mundi-1"
],
[]
] |
||
1xs3j5
|
why are carbs the largest part of the food pyramid when popular diets & new research says to cut them out?
|
I first learned of the keto diet after joining Reddit which is a diet that cuts out majority of your daily carbohydrates (consuming approx 20 a day). Since then not only have I discovered more benefits to Keto but also the Mediterranean and Paleo diets have seem to become more popular because they cater to the body's basic needs instead of cravings. I also started reading the "Story of the Human Body" by Daniel Lieberman (haven't finished yet though) and it explains how our bodies haven't adapted as high of a tolerance for carbs as society likes us to believe. Just curious if all of this research is proving that carbs are so bad and cause large weight gains amongst people, why are they still supposed to be the largest part of our diet?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1xs3j5/eli5_why_are_carbs_the_largest_part_of_the_food/
|
{
"a_id": [
"cfe4zdp"
],
"score": [
3
],
"text": [
"I've read that the food pyramid was created in the Department of Agriculture by people who hadn't studied nutrition.\n\nPeople in government who make policies are often ignorant, misguided, or cynical."
]
}
|
[] |
[] |
[
[]
] |
|
34jv0b
|
How did Abraham Lincoln become so politically popular in a time when many of the important things he is remember for today were considered radically liberal?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/34jv0b/how_did_abraham_lincoln_become_so_politically/
|
{
"a_id": [
"cqvcuag",
"cqvdi0h"
],
"score": [
4,
2
],
"text": [
"You may want to check your premises - there is little evidence to suggest that Lincoln was exceptionally popular as President, and indeed a fair case to be made for his unpopularity. While polling data is obviously unavailable, the Republican Party lost hugely in the midterm following his election. His re-election could easily be credited with the fact that Lincoln *was not* McClellan, who ran on a platform of ending the war at any price just at the time that the war started going well. ",
"Lincoln' reelection in 1864 completely hinged on the Union gaining a decisive victory. He had written a letter for the next president, completely thinking he was going to be beaten. Antietam was the first real turning point that rallied the North to back Lincoln's reelection. That and the ballot boxes being sent into the field for soldiers to vote. Lincoln received 80% of the soldier vote."
]
}
|
[] |
[] |
[
[],
[]
] |
||
315yc2
|
How does a Human compare in efficiency/output vs an Internal Combustion Engine?
|
We have Internal Combustion engines that can run on vegetable oil, and convert the energy into mechanical force, expelling CO2. Humans can do largely the same thing by consuming vegetable oil and turning a crank of some sort.
How do we compare? Are we more efficient? How many humans would have to be working together to run at the horsepower of a typical engine?
|
askscience
|
http://www.reddit.com/r/askscience/comments/315yc2/how_does_a_human_compare_in_efficiencyoutput_vs/
|
{
"a_id": [
"cpz1rlv",
"cpzchpt"
],
"score": [
5,
2
],
"text": [
"I'm not exactly sure what the question is: is it which is more efficient at energy consumption or which is more efficient at turning energy into mechanical work? Humans are pretty good at consuming things and using that energy to survive (including converting it to some mechanical energy of course). However, much of the energy we consume is not used to perform mechanical output. In short, humans are more efficient at using energy, but not at turning energy into mechanical work.",
"[Here's a rough idea of a car's efficiency](_URL_0_). An engine is 30-40% efficient, and then converting that power to the wheels (and idling/braking at stoplights) brings the overall efficiency down to 13%"
]
}
|
[] |
[] |
[
[],
[
"http://1.bp.blogspot.com/-ojpG_uEzOog/T8aNsrfeIOI/AAAAAAAABJQ/NSiswXwVdKU/s1600/13percentefficiency.png"
]
] |
|
1od9kt
|
How did 19th century armies maintain cavalry units?
|
t seems like in my entirely non-academic concept of 19th century armies, there were lots and lots of horses used in battle, and surely large numbers of them would be killed in combat. How did large scale armies maintain large amounts of cavalry? Were countries running military ranches with the sole purpose of raising horses for the army, or were horses just so ubiquitous that they could be easily procured anywhere and everywhere? Was it a supply issue to keep that many horses fed and healthy during a long campaign?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1od9kt/how_did_19th_century_armies_maintain_cavalry_units/
|
{
"a_id": [
"ccr2d2d"
],
"score": [
9
],
"text": [
"Yes, all nations that fielded a sizable cavalry force kept extensive stud farms. Not only enemy bullets, bayonets, sabers or lances killed horses - diseases and lack of fodder also did quite a bit.\n\nIt was not uncommon to see parts of the cavalry walking with their saddles on their shoulders during a campaign for a lack of horses. \n\nCavalry horses are expensive and precious - you cannot just seize whatever horses the local farmes have and ride them - you need a horse that can take instructions to remain in formation, that does not panic in the heat of battle with the sounds of battle (firing, wounded crying out, dying horses screaming etc). Cavalry horses also needed to be large and strong to improve the weight of the charge - such animals are expensive to keep (they need a lot of high-quality fodder) and raise and are often ill-suited to farm work.\n\nPart of the reason why Napoleon's famed light cavalry never really recovered from his devastating Russian campaign was that he lost access to the extensive Polish and East Prussian stud farms and the horses supplied from them. \n\nThe cavalry was supposed to bring a supply of remounts with them on campaign, and captured enemy horses were often taken into service. The horses were fed by what was taken from the land - oats, hay and straw mostly. This meant that the cavalry needed to spread out to plunder this from the countryside, and the enemy army would often do the same - regardless if they were in their own territory or not. Foraging parties would often clash in small-scale battles and the side that had the better light cavalry could forage and keep their cavalry in better shape. Losing this battle could be a vicious downward spiral, as it was to the French in Russia 1812, when the masses of Russian irregular cavalry (mainly Cossacks) kept the Grande Armée starved, blind and hemmed in."
]
}
|
[] |
[] |
[
[]
] |
|
d3iuyc
|
what happens in the body that causes a physical reaction to a funny joke?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/d3iuyc/eli5_what_happens_in_the_body_that_causes_a/
|
{
"a_id": [
"f03gli8"
],
"score": [
3
],
"text": [
"Not an expert but id assume our brains processes something we find truly funny and cause involuntary movement in our face to express happiness and form a smile. Id also assume laughter was first used as communication when speaking wasn’t an option."
]
}
|
[] |
[] |
[
[]
] |
||
cjeizq
|
how are animals like felines able to jump and leap insane distances? what makes humans unable to do the same?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/cjeizq/eli5_how_are_animals_like_felines_able_to_jump/
|
{
"a_id": [
"evcs0nc",
"evcx4z5",
"evczpqt",
"evczut4"
],
"score": [
8,
3,
22,
7
],
"text": [
"A cats body is better suited for being lean and agile, it was just created like that by evolution to behave so, humans legs aren't like cats, were much more stuff and strudy because of our evolution. When we were cave men we weren't jumping around trees or trying to pounce on our prey. TLDR: evolution and our genetics are just too different to behave like cats.",
"Keyword: Hind legs/limbs\n\nCats and Dogs for example have a common back-leg feature called hind legs. Hind legs allow an animal to experience a greater range of motion in the leg, and therefore power when the legs become fully stretched during a jump.\n\nHumans would actually be able to jump higher if given hind legs, but usually four-legged animals have these.",
"The design of the hind legs has a lot to do with it. \n\n\nAnimals like cats and deer walk on their rear toes. The \"heel\" is quite high off of the ground. So their rear legs have three major segments instead of two, giving them more power and range of motion. This leads to bigger jumps. \n\n\nAnd you also have to be able to land safely. Humans have to land on the same legs that they jumped with. Four legged animals jump with their rear legs, and land with their front. The front legs and their joints have evolved to be great shock absorbers. For example, the shoulder joint of a deer has an incredible range of motion, because there's no direct connection from the leg bone to the bones of the torso. It's all just connected by soft tissue.",
"[Square/Cube law.](_URL_0_)\n\nSimplest way I can say it: as something gets bigger on the outside (taller, longer, etc), it gets significantly **more** bigger on the inside (weight). It's the same reason that much larger animals (elephants, rhinos) can barely jump at all. \n\nYou can see the square-cube law at work in normal humans. An average 2-3 year old human will weigh about 30 pounds, and be roughly 3 feet tall. A full grown adult male will be around 6 feet tall, and roughly 180-200 pounds. Though these numbers will obviously vary from person to person, you can see the distinct trend. At double the height, a human weighs 6 times as much. \n\nBut to your point, you can see a similar trend the jumping capabilities of cats. An average house cat is 9 inches tall at the shoulder and weighs 10 pounds. They can jump 6 feet vertical. A average tiger is roughly 3 feet tall at the shoulder and weigh 500 pounds (though it varies a lot by gender and subspecies). They can jump 12 feet vertical.\n\nAt 4x the height, a tiger can only jump 2x the distance, because of the square cube law (and 500x the weight)"
]
}
|
[] |
[] |
[
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Square%E2%80%93cube_law"
]
] |
||
1uwq23
|
how does a car measure it's speed to show up in the speedometer? what happens if the car is replaced with wheels of different diameters? does it matter?
|
Title.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1uwq23/eli5_how_does_a_car_measure_its_speed_to_show_up/
|
{
"a_id": [
"cemet4b",
"cemetf7",
"cemi0qz"
],
"score": [
2,
13,
5
],
"text": [
"It is tuned with a factor of the output RPM from the transmission. If you use larger tires, the speed displayed is less than your actual speed.\n\nSource: I used to own a car with 70R14 tires whereas it came from the factory with 65R14 tires.",
"It measures its speed by sensing each time a wheel makes a full rotation. So yes changing to a wheel with a different diameter then stock will throw the measurement off. This can usually be fixed by a reprogramming tool (for newer vehicles)\n\nSome vehicles use GPS based speedometers. But I don't believe this is a very common thing. In this case wheel size has no effect. ",
"There are three possible methods a car could use.\n\nI've heard of GPS speedometers which constantly determine your position on the Earth then divide the distance between two coordinates found by the time between when each coordinate was found. I've never seen one of these, only heard rumors they exist in vehicles. The main problems with this method are remaining connected to the GPS satellites and getting precise data. Many GPSs have a poor spatial resolution, meaning they will know your location to within a fairly large distance of possibly thirty feet or more. In addition, because the signals used for communication are so weak when they arrive, (satellites are really far away), if you are in a tunnel, under a bridge, in a city with a lot of tall towers, or experiencing bad weather, you could lose the signal. These problems make me doubt these systems are actually used in vehicles. This method does not rely on the wheels' radius.\n\nAnother method is to have one or more magnets attached to a shaft somewhere in the powertrain. When these magnets rotate, they induce electric currents in a coil of wire as they pass by it. Each time a magnet passes by this coil, a pulse of electricity is generated. The frequency of these pulses can be measured, and if the gear ratio between the shaft and the wheels is known, and if the radius of the wheels is known, the rotational speed of the wheels can be determined mathematically.\n\nThe third method involves more magnets and a larger coil of wire. When the magnets on a shaft are rotating, they induce an electric current in a coil of wire, (this time, the current is continuous, not pulsed.) This electric current is amplified and used to heat a strip of metal. This metal strip actually consists of two different types of metal sandwiched together. When the strip heats up, the metals expand, but each of the two metals expands by a different amount causing the strip to bend. The strip is connected mechanically to the speedometer, so when the strip bends, the indicator moves. The amount it moves is ultimately dependent on the speed of the shaft containing the magnets, as is the speed of the vehicle. This method also relies on having a known wheel radius.\n\nEDIT: If the wheel diameter is changed, the vehicle's firmware can be modified to accommodate for this."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
us7v4
|
Can cats or dogs see what's on a TV or computer monitor?
|
I have long been under the impression that cats and dogs could not see what was on a TV screen or computer monitor because their eyes could not compensate for the refresh rate designed for human eyes.
However, I was recently searching online for the answer to this question (to settle an argument) but every page I have found conflicts with another.
For the most part, all the evidence I've read for either side is either uncited or completely anecdotal.
I thought I'd give Askscience a go and see if you all can sort fact from fiction.
|
askscience
|
http://www.reddit.com/r/askscience/comments/us7v4/can_cats_or_dogs_see_whats_on_a_tv_or_computer/
|
{
"a_id": [
"c4y5srm",
"c4y6vs3"
],
"score": [
5,
2
],
"text": [
"Please avoid anecdote. The answer should not include the words \"my cat\" or \"my dog\". Instead please cite research.",
"In this study \"[Dogs do look at images: eye tracking in canine cognition research](_URL_1_)\" the researchers used\n\n > a 22\" LCD monitor (1,680 x 1,050 px)\n\nand it looks like the dogs were able to see the images on the monitor.\n\nEdited to add:\n\nFrom the [DOGTV faq page](_URL_0_):\n\n > I heard dogs view television picture as flickering. Is that true?\n\n > The human eye discerns flickering movement at a rate of 50-60 Hz while in dogs, that same ‘flicker fusion rate’ is as high as 70-80 Hz. Older television sets, with a CRT screen, refreshed their picture at a rate of 50-60 Hz with the result of a smooth picture for humans and a flicker nightmare for dogs. New LCD technology however, has changed all that. The refresh rate on the newer television screens is now 100Hz and up, perfect for continuous canine viewing. "
]
}
|
[] |
[] |
[
[],
[
"http://dogtv.com/Faq#",
"http://www.cogs.indiana.edu/spackled/2012readings/Somppi_Dogs%20do%20look%20at%20images_2012.pdf"
]
] |
|
1c50oz
|
When did the use begin of such stylized symbols as the arrow (→) and heart (♡)?
|
I'm curious to know when and how certain symbols, which are now ubiquitous and taken from granted, came into use. I could ask many such questions (and any related symbol interests me) but I'll concentrate on just two of them:
* The stylized arrow (something like this: →), used to indicate a direction or to draw attention to a certain item or place. My intuition suggests that this started being used sometime in the 19th century, and that arrows were initially much less stylized, having a prominent tail, perhaps even drawn with fletchings, which disappeared later on. Is this correct? Is it possible to identify the first arrow used as an indication of direction or to draw attention (as opposed to representing the projectile), or the approximate date? (The Egyptian hieroglyph T11, viz. 𓌕 if you have the appropriate Unicode font, really seems to stand for the projectile and not an indication of direction in any case.)
* The stylized heart (something like this: ♡), used to indicate love. There are actually two different questions here: when did the heart come to be stylized in this particular way (which only faintly resembles an anatomical heart), and when did the heart come to be used to symbolize love (as opposed to: life, courage, strength, etc.). (Again, the Egyptian hieroglyph F34, 𓄣, does not look very much like the modern stylized heart ♡, and seems to stand for an actual heart, not love.) A probably related question is how the heart became one of the four standard card suits.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1c50oz/when_did_the_use_begin_of_such_stylized_symbols/
|
{
"a_id": [
"c9d5a2s",
"c9d79oi"
],
"score": [
4,
2
],
"text": [
"I don't know about the arrow, but I heard that the heart symbol as a symbol of love originates in [silphium](_URL_0_), whose seeds had the exact same shape.",
"I'll bet dimes to doughnuts one of the type heads in /r/ design has one of those symbolism encyclopedias which often include forwards with historical provenance. ---\n_URL_0_\nBingo."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Silphium"
],
[
"en.m.wikipedia.org/wiki/Heart_(symbol)"
]
] |
|
2yxv05
|
why is the water colder in the water bottle than the outside of the water bottle temperature
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2yxv05/eli5_why_is_the_water_colder_in_the_water_bottle/
|
{
"a_id": [
"cpdyowc",
"cpdyr5u"
],
"score": [
2,
2
],
"text": [
"It isn't. It just *feels* that way.\n\nWhen you feel something as hot or cold, you're not actually feeling temperature. You're feeling heat flowing either into or out of your body. Some materials conduct heat better than others, so heat will flow into you or out of you faster. This is why room temperature metal feels cold, but room temperature wood doesn't - metal pulls the heat out of your skin faster than wood does. Water is the same way. Water conducts heat better than air. So if water and air are at the same temperature, the water will feel colder.",
"You might be *feeling* a different temperature but they are actually the same. Veritasium explains this well. Basically it's because heat moves out of your hand into some things faster (into water faster than air, for example) so those things feel to us like they are colder. This is also why metal feels colder than paper, even if they're in the same room (and are actually the same temperature). \n\nHere's a good video on it. \n_URL_0_"
]
}
|
[] |
[] |
[
[],
[
"https://youtu.be/vqDbMEdLiCs"
]
] |
||
98jybr
|
why can my aches and pains "reset" by doing more exercise?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/98jybr/eli5_why_can_my_aches_and_pains_reset_by_doing/
|
{
"a_id": [
"e4gln3u"
],
"score": [
12
],
"text": [
"By reset, I assume you mean a brief yet acute dulling of pain. This is due to something known as exercise-induced hypoalgesia. As the muscles start aching, they activate the pain related nerves in the body, known as A-delta and C fibres. This pain is alleviated by two main mechanisms, Gate Control Theory and Descending Inhibition. According to the former, if other touch receptors are activated, it activates inhibitory neurons, which will in turn inhibit the pain. This explains why rubbing the injured area might lessen the pain. But our focus here is on the latter. So there exist in the brain certain areas, PAG and RVM, which have high levels of natural opioids i.e. endorphins. These opioids, using serotonin as a transmitter, are projected into the spinal cord, alleviating your pain for at least 20-30 minutes after exercise. So when muscles start paining during exercise, these endorphins are activated. \n\n\nThis exercise-induced hypoalgesia is characterized by an increase in pain tolerance, and reduction in pain intensity during and after exercise. In effect, it resets the aches and pains. \n\n\nHope this answers it, if it is what you meant and were looking for."
]
}
|
[] |
[] |
[
[]
] |
||
1kmsez
|
How is it people can remain hydrated when the majority of beverages they drink are diuretics, like coffee, beer and soda?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1kmsez/how_is_it_people_can_remain_hydrated_when_the/
|
{
"a_id": [
"cbqiokp",
"cbqjex6"
],
"score": [
3,
2
],
"text": [
"Coffee, Beer, and Soda contain a LOT of water, far outweighing any diuretic effect from it's ingredients. \n\nWe can drink nothing but double-strong black coffee, while eating a few coffee beans for good measure, and still stay hydrated with ease. ",
"The idea that \"coffee doesn't hydrate you because caffeine is a diuretic\" is false. It is simply less effective at hydrating than pure water because it causes you to urinate slightly more. It's not that it has no hydrating benefit at all. As in, drinking 12 oz. of coffee might produce the same amount of useful hydration as drinking 8 oz. of water."
]
}
|
[] |
[] |
[
[],
[]
] |
||
169hzt
|
Do Emergen-C and similar products actually do anything?
|
I've heard that they do not help in actually preventing colds, but they may aid in decreasing the duration. What are the known effects?
|
askscience
|
http://www.reddit.com/r/askscience/comments/169hzt/do_emergenc_and_similar_products_actually_do/
|
{
"a_id": [
"c7u49p2"
],
"score": [
2
],
"text": [
"The science behind this question is as follows: immune cells have high Vitamin C concentrations, and you use up Vitamin C faster when you're sick. However, this will only be a major health issue for you if you are already significantly Vitamin C deficient. Most humans in the developed world actually are getting well over their daily value of Vitamin C without supplementation. Because of this, your average Emergen-C/Airborne type product works mainly through a placebo effect.\n\nArticle on this topic if you want to learn more:\n_URL_0_"
]
}
|
[] |
[] |
[
[
"http://www.slate.com/articles/health_and_science/medical_examiner/2008/03/your_health_this_week.html"
]
] |
|
49crx8
|
How serious was ballroom dancing in the 18/19th century?
|
I've seen in movies, and in a ballet some really extreme precision ballroom dancing. At least in the movies there could be fifty people all dancing perfectly, switching partners and using a large variety of moves. Obviously that is through the magic of Hollywood and a ballet troop, but how intense were these dances actually?
At a ball would almost most attendees dance? And would they all dance fairly well, or would people be screwing up and getting run over by other dancers? If I could really tear it up on the dance floor in Paris and I took a trip to Vienna or St. Petersberg how would I fare, would I need lots of practice for new dances?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/49crx8/how_serious_was_ballroom_dancing_in_the_1819th/
|
{
"a_id": [
"d0rg19k"
],
"score": [
39
],
"text": [
"I'd like to apologize for my exuberance and outburst of writing in this thread. It's extremely rare that a question related to my specialty comes up.\n\nIn short:\n\nI've written a considerable amount below. The basic summary is that no, dances of the era were not the precise, complex choreographies of ballet performances and Hollywood. They were primarily intended as social dances, with a decreasing emphasis on displays of individual skill, and had the somewhat the same separation you see today between casual social ballroom dance and modern competitive ballroom dance. Complex, precise performances did take place during the era, but served other purposes, like theatrical productions, ceremonial occasions (eg, the ball in Trollope's Way We Live Now), or the promotion of dance masters and their paid instruction. This difference is a product of different purposes of different dances, as we see today.\n\n-----\n\nI am on a train at the moment, and being thus unfortunately deprived of direct checking of my usual sources, I will have to resort to citing from memory at the moment. When I return home, I should be able to revise the post somewhat.\n\nDance serves a variety of purposes: ceremony, performance, social interaction, and so on. A discussion of dance difficulty, \"intensity\", and so on requires a differentiation between the purposes of the dances involved. \n\nHollywood, and modern performances in a particular period, often portray dance in the 18th and 19th centuries as being ceremonial, and often do so with choreographed performances. These styles of performances were not unknown in those time periods. For example, I believe it is either Strathy or Wilson who notes, in the early 19th century, that \"skilled\" (not the right word, I will replace later) dancers would often replace standard footwork in country dances and quadrilles with their own: Ellis Rogers suggests that by this they were referring to professional dancers dancing in performances, and I tend to agree. Giraudet, in *Traite de la Danse*, I believe has several references to quadrilles that are primarily intended for performance, and they are, as might be expected, considerably more complicated than dances intended for social occasions: this at a time when quadrilles had become a dance of the middle classes. One might suggest that many partner dances in Gilbert's *Round Dancing* are for similar purposes, or for promoting the skill of dance masters and thus their services: it seems unlikely for example, given the tendencies of contemporary dance manuals and references to dances, that many social dancers were dancing highly complex, syncopated waltz variations. \n\nLike modern performance and modern ballroom dancing, these dances were choreographed, done with familiar, practiced partners. This is quite distinct from social dancing.\n\nOf course, you are discussing quite a long period of time and a large area. Restricting our view to my specialty (England and America, which to some extent includes France), there were three predominant styles of social dance: country dances, quadrilles, and round dances.\n\nCountry dances, popular in England up until the end of the Regency era, were not choreographed, despite the modern depiction of them. While danced by lines of couples, they tended to be improvised by the lead couples in each set, with the dance passing down the line as dancers watched and had the lead couple possibly call the figures (see de Guardiola's discussion of historical progression). Such dances served a few purposes at once: they allowed social conversation between dancers who were not dancing at the moment, social interaction between all the dances, and some displays of dance skill and thus refinement. \n\nYet while the ideal of these dances was a precise, organized dance of coordinated figures and ballet footwork, the reality appears to have been quite different. For every book Wilson, always the purist, sold of complex diagrams and equations describing how to improvise a complex country dance in one's head, there were numerous little manuals of pre-set, fashionable dances for ladies to memorize and present as their own. These dances tended to be *far* less complex than modern performances of country dances, or even modern social English Country Dance, where the dances are taught specifically. And they still tended to be chaotic.\n\nWhile Wilson had his own motivations for disparaging dancers and encouraging more paid instruction, his *Danciad* decries all manner of chaos and disorder at balls. And this is supported by less biased sources. Dickens, in the mid/late-18th century ball scene of A Christmas Carol, describes a ball where *not a single country dance is actually finished*, instead each descending into confusion and missteps until the dancers simply gave up and applauded happily. Rules for some subscription balls of the 18th century suggest that couples leading dances be given, in one case, *three tries* at leading a country dance and having it fall apart before being asked to step aside and let the next in line lead! (I believe this may be in the Bath New Assembly Rooms rules?)\n\nHaving a theoretical basis in ballet does not imply precision, either. It is generally considered, for example, that while ideal ballet turnout was usually seen as close to 180°, social dances usually involved turnout of around 90°. With training but without serious, professional practice, footwork was almost certainly sloppy by comparison to ballet, and the footwork tends to be simple both in variety (most country dances involve chassés, balancé-assemblé sequences, and one or two memorized setting steps) and descriptions in social dance manuals relative to actual ballet. \n\nStill, these were dances done primarily by the upper classes. They did have *some* element of performance to one's peers in them, and dancing was seen, as cecikirk notes, as part of upper class education. \n\nAs one note here about modern depictions: modern depictions of country dances are almost entirely inaccurate not just in style but in the way that style represents social views and culture of the eras involved, usually being based in the modern English Country Dance tradition likely started by Cecil Sharp in the 1920s. Actual country dances were not slow, \"stately,\" prudish dances. They were instead energetic and athletic. de Guardiola writes extensively about this and it is a source of considerable annoyance.\n\nThe quadrille, on the other hand, with four couples dancing together in a square, is a dance that underwent considerable transition over the 19th century after becoming wildly popular, at least in England, after 1815. In its earlier form as dance of the upper classes, Ellis speculates that it offered considerable advantages over the country dance: figures were fixed and learned, dances were not ridiculously long (a single country dance in the 18th century might last 30 minutes), and yet there was more opportunity for individual performance. At that time, it could be seen as similar to country dances, but less likely to fall apart.\n\nYet as part of economic transitions throughout the 19th century, and changes in the popularity of dances, the quadrille became increasingly a dance of the middle classes. Footwork, by the middle of the 19th century, was almost entirely missing from instruction manuals, or even decried as pretentious. Dances were largely walked through, something that would have been seen as unacceptable a half century earlier (there is a Mansfield Park reference I need to add here), and the basis in ballet mostly disappeared (I am also skeptical of Ellis' speculation that earlier styles of quadrille persisted amongst the upper classes). Quadrille figures were simplified, and areas meant for individual performance were almost entirely removed. The purpose of the dances became yet more focused on sociality and entertainment than they had been in the past.\n\nIn this era, I believe it is either Hillgrove or Dodworth who, while again having their own motivations, spoke of balls where scarcely one set of dancers could be formed that would actually know a quadrille. There are also several other sources that suggested the quadrille fell rather out of style despite continuing to be played. \n\nRound dances, like the waltz, polka, and so on, which became increasingly popular from the 1830s onward, were entirely different. These were partner dances in the modern conception, and were social. They were, even by necessity, less focused on performance than early quadrilles and country dances: with everyone dancing at once, and focused on their partners, there simply isn't the same visibility. \n\nThere were certainly variants of these dances that were precise, difficult, and probably intended for performance, as I mention with Gilbert earlier. Yet the vast majority of dance manuals suggest that these were largely not danced. All evidence I have found suggests that the vast majority of dancers were dancing socially, and dancing only the simplest steps or the latest fad (usually poorly). For example, something requiring significant dance skill, like a Highland schottische, finds actual reference only in a handful of dance manuals and an exhibition performance for Victoria. There is even reference to one prestigious military regiment having a tradition of only dancing basic waltzes in one direction, never doing reverse turns! These dances were a time for social interaction, not for ceremony and performance; the idea of such dances being done as part of a larger choreography has no place outside of contemporary performances and Hollywood.\n\nI'll update this further when I return home, and possibly try to make it more concise!"
]
}
|
[] |
[] |
[
[]
] |
|
fq7ng
|
Why is it that the more viscous a liquid, the more sticky it is? More importantly, how does "sticky" work?
|
For example, if I was to submerge a gold bar into a vat of honey, why would some honey be left on the bar when I pull it out? Shouldn't the lower density liquid be able to easily fall off?
My deepest respect to those of /r/askscience for spending valuable time answering the idol questions of the average person.
|
askscience
|
http://www.reddit.com/r/askscience/comments/fq7ng/why_is_it_that_the_more_viscous_a_liquid_the_more/
|
{
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"text": [
"Viscosity is about flow, right? It flows more slowly. So it will drip off the object, just take more time to do it. There's a famous \"[pitch drop experiment](_URL_0_)\" that flows so slowly that it has had 8 drops since 1938. That's how slowly it flows. \n\nFinally if you think about it from the standpoint of stickiness, think about pressing your hand to a flat surface covered in honey. As you pull your hand up and off that surface, the honey is slow to flow away from your hand, creating a partial vacuum between your hand and the surface (since the honey is still sealing it shut). The air pressure on top of your hand pushes it down, but there's no air to push it back up so you have to actively work against that pressure difference.",
"Viscosity and stickiness are somewhat related but not the same. For example, motor oil is somewhat viscous but is used to lubricate parts that move past each other.\n\nViscosity is a substance's resistance to flow. Stickiness is the ability of a substance to adhere to other substances.\n\nHoney is a dense solution of carbohydrates among other things. The abundant -OH groups in those molecules can form lots of hydrogen bonds and make the substance _sticky_ or _tacky_. The high concentration makes the normally not-very-viscous water more resistant to flow.\n"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Pitch_drop_experiment"
],
[]
] |
|
2oqca8
|
why (chemically/psychologically) does some music make me feel like an unstoppable badass?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2oqca8/eli5_why_chemicallypsychologically_does_some/
|
{
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"cmpsiu2",
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"text": [
"It's to do with association, this is why different music evokes different emotions for people, you begin to associate yourself to a suspension of your own disbelief in a subconscious manner, thereby making you actually feel like you're about to take on a whole army just because you're listening to The Lord of the rings soundtrack as you walk your dog or something.\nIt's the same with how sad emotional music can make you reflective or calm, it's just your own experiences and memories telling you how you're \"supposed\" to feel, and it's a key difference and also the same thing in the way popular music and film scores are composed\nIf anyone wants to reword all that feel free\n",
"These are all bullshit answers. Try askscience.",
"It has to do with association, but it probably also has to do with a dopamine response in a region of the brain called the ventral striatum--a region whose primary job is to inform you when stimuli is rewarding. It's the same region that makes one feel unstsoppable after sniffing a fat line of cocaine. Of course, other regions are too working in unison, as no one region works alone in these dealings, but the ventral striatum is quite active when that amazing song comes on. Word.",
"When it comes to live gigs, depending where you live..... Australia has limits on SPL, but US bands that tour here will often push these.\n\nAt 125db+ SPL your body is having an adrenalin fear response. Basically screaming in panic about the permanent hearing damaging you're doing to yourself. The rush is your body telling you to get out of the hazardous environment, misinterpreted as \"fun\"....\n\nToo many bands abuse this, killing their fans hearing just to get generate a euphoric response in audience.\n\nIf you listen to ear-buds/headphones this loud, there is little that can be done to save you."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
3i1dem
|
History terminology word help!
|
I can't think of the word, and I know it's basic but I've been writing this essay for too long and my brain has pretty much shut off.
So what is the word for when you look at two sides/two sources to reach a middle ground... it starts with a d I'm pretty sure.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/3i1dem/history_terminology_word_help/
|
{
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"cuchzoo"
],
"score": [
3
],
"text": [
"I think you are referring to dialectic, possibly? Although dialectical reasoning is supposed to result in a reasoned, rational answer rather than a middle ground per se, as I understand the term."
]
}
|
[] |
[] |
[
[]
] |
|
koj8m
|
Is it possible to overwork your brain?
|
The question above.
|
askscience
|
http://www.reddit.com/r/askscience/comments/koj8m/is_it_possible_to_overwork_your_brain/
|
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"text": [
"In certain ways, [yes](_URL_0_).",
"This works on many levels:\n+ All cells are not able to power itself and clean up at the same time, so the more it works the dirtier it gets inside, then you sleep/rest, they clean up. When working at a higher capacity, it's even worse.\n\n+ We stay awake because the brain keeps signaling the Reticular Formation with time and exhaustion these signals stop.\n\n+ On an Endcorinal level, we have pulses of Cortisol, and much less importantly Thyroid Hormone and Pineal Body and even less importantly Growth Hormone; these are you're endogenous energy drinks, specially alertness, span, cognition, ..etc\n\n+ On a cellular level, the more a tissue exercises the better its blood supply gets (neovascularization & collaterals) and the more power plants it constructs (mitochondria), the Brain has an additional perk which is improving the wiring. \n\nSo like how you can exhaust yourself in an exercise your brain can be exhausted, if you were a regularly exercising your endurance would be better. And like how there are lower body or upper body exercises, there are areas in the brain like complex motor movements (cerebellum + cortex), cognition (frontal lobe), memory (many places), imagination, imaging (occipital), smelling (frontal), hearing (parietal), ..etc",
"In certain ways, [yes](_URL_0_).",
"This works on many levels:\n+ All cells are not able to power itself and clean up at the same time, so the more it works the dirtier it gets inside, then you sleep/rest, they clean up. When working at a higher capacity, it's even worse.\n\n+ We stay awake because the brain keeps signaling the Reticular Formation with time and exhaustion these signals stop.\n\n+ On an Endcorinal level, we have pulses of Cortisol, and much less importantly Thyroid Hormone and Pineal Body and even less importantly Growth Hormone; these are you're endogenous energy drinks, specially alertness, span, cognition, ..etc\n\n+ On a cellular level, the more a tissue exercises the better its blood supply gets (neovascularization & collaterals) and the more power plants it constructs (mitochondria), the Brain has an additional perk which is improving the wiring. \n\nSo like how you can exhaust yourself in an exercise your brain can be exhausted, if you were a regularly exercising your endurance would be better. And like how there are lower body or upper body exercises, there are areas in the brain like complex motor movements (cerebellum + cortex), cognition (frontal lobe), memory (many places), imagination, imaging (occipital), smelling (frontal), hearing (parietal), ..etc"
]
}
|
[] |
[] |
[
[
"http://www.nytimes.com/2011/08/21/magazine/do-you-suffer-from-decision-fatigue.html?pagewanted=all"
],
[],
[
"http://www.nytimes.com/2011/08/21/magazine/do-you-suffer-from-decision-fatigue.html?pagewanted=all"
],
[]
] |
|
186hzm
|
Is it possible to ever hear a pure square wave?
|
Given that speakers take time to move back and forth, is it possible to ever truly hear a square wave, or would everything we hear be rounded off a bit? How close could we get to a pure square wave?
|
askscience
|
http://www.reddit.com/r/askscience/comments/186hzm/is_it_possible_to_ever_hear_a_pure_square_wave/
|
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"text": [
"To *hear* a purely square wave your eardrum would need to teleport backwards and forwards. If the ear was exposed to a pure square wave, the eardrum would wobble back and forth in tune with the wave, although the sound heard would indeed be rounded off. I'm not an expert, but no one's commented yet so take it with a grain of salt.",
"If you take a square wave into the frequency domain you end up with a sinc function centered on the square waves frequency. This is a rather wide function. This makes sense if you think about; it the flat parts of a square wave don't change (low frequency) while the sharps edges change suddenly (very high freq). A \"perfect\" square wave has frequency components heading off into infinity. \n\nYour ear has a frequency range of 10 Hz to about 20 Khz (rounded up) you couldn't fit a proper square wave into that frequency range. \nSo no matter how good the speaker was it wouldn't matter, you couldn't hear it. \n\nHow do I know this? I had to install some cheap, crappy sound-card oscilloscopes into a university lab. They sampled up to 44k and guess what function we couldn't see properly on 'em. Plus you know, multple degrees in electronic engineering.",
"Even though everyone here is right about a perfect square wave being impossible to produce, I am going to say that it might be possible to hear it. That's because you hear not with your ears, but with your brain. So while it is impossible to physically produce a square wave, the sensation of hearing such a wave could be produced by inserting electrodes into the appropriate areas of the auditory cortex and stimulating it."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
durzuh
|
How do Scientists Make Protons?
|
I know protons are used in the Hadron colliders and even in cyclotrons for radiation therapy. But how are these protons made in the first place?
|
askscience
|
https://www.reddit.com/r/askscience/comments/durzuh/how_do_scientists_make_protons/
|
{
"a_id": [
"f782rk8"
],
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"text": [
"You just buy a bottle of hydrogen gas, and heat up hydrogen molecules until they dissociate. \n\n[Here’s](_URL_0_) some more detail about the LHC source."
]
}
|
[] |
[] |
[
[
"https://www.lhc-closer.es/taking_a_closer_look_at_lhc/0.proton_source"
]
] |
|
2hbs83
|
if food takes longer than 24 hours to digest, then why do i take a massive fiery dump within an hour or two every time i eat spicy asian food?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2hbs83/eli5_if_food_takes_longer_than_24_hours_to_digest/
|
{
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"ckr72k3",
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3
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"text": [
"The spicy food can irritate your stomach and make your bowels react by clearing what ever is in the pipeline, so to speak. ",
"Food typically takes 12 hours to digest. If the food is irritating to your stomach or intestines, the body will speed up the process as best it can, though. If there's enough oil in the food, the \"fiery\" part (capsaicin) will be carried particularly fast as it is dissolved and carried in the liquid portion of the goo flying through your gut.",
"Your body thinks that it's something harmful so it dumps it as fast as possible. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
2zlhfm
|
why denying the holocaust is not protected under the freedom of expression? and why denying other genocides/mass killings is not criminalized in any countries?
|
I'm not a denier, but this dilemma has always baffled me.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2zlhfm/eli5_why_denying_the_holocaust_is_not_protected/
|
{
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"text": [
"Not all countries have the same level of freedom of speech as the US. Many qualify hate speech as being illegal and some of those classify denying the Holocaust as being hate speech. ",
"If you are in America you are very much allowed to deny the holocaust all you want. ",
"becouse you are asuming other countrys are like america, laws are diffrent and freedom of speach is diffrent in other countrys in most first world countrys hate speach is illegal.",
"In the US, denying the Holocaust IS protected under freedom of expression. In some other countries, even those with fairly liberal free speech policies, there is not the same blanket free speech protections as in the US, and specific forms of expression (like hate speech) can still be forbidden.",
"It's been legally accepted as fact that the holocaust did happen, there is too much proof to deny it. \n\nIt is criminalized in other countries.\n\nAustria covers that under \"hate speech and racial vilification\"\nBelgium covers it under a 1995 law specifically pertaining to the holocaust.\nCzech Republic enacted a similar law in 2001.\nFrance enacted the Gayssot act in 1990, which prohibits denial of crimes against humanity as defined by the London Charter of 1945.\n\nI could continue for quite a while, many developed countries have laws against denying crimes against humanity.",
"Denying other genocides is also punishable in some European countries (see Armenian Genocide). Denying the Holocaust is a crime in some European countries because it basically amounts to hate speech.",
"Holocaust denial is a crime in European countries as the Holocaust was a modern genocide carried out by Europeans. They wish to avoid a repeat. \n\nMany of the laws prohibit denying any genocide but the Holocaust is singled out for valid reasons. The idea, in part, is to stop another genocide from occurring and to stop another nazi party from forming. ",
"I think the simplest reason is that in Europe we have more of a 'feeling' for the Holocaust than most Americans, as well as not having the same tradition of \"free speech at all costs\".\n\nI believe the argument in the UK is that one is free to say what one wants regarding racism, etc. so long as it isn't inciting violence, and that denying the Holocaust is intrinsically an act of violence.\n\nAlso, most other genocides aren't as denied/ weren't as... brutal, as the Holocaust (not to suggest that x genocide is more worthy of attention than y genocide).",
"It is protected. But that doesn't mean no one can criticize you for saying that.",
"In the US, rights around speech or expression have less to do about certain categories of things but about who has the right to punish someone. It might be more accurate to say that the government lacks the right to punish someone for being a Holocaust denier. Someone might have the right to deny the Holocaust or not, but the US doesn't grant any government the right to decide that question."
]
}
|
[] |
[] |
[
[],
[],
[],
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[],
[],
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|
n5e83
|
Are there any theories on the future of evolution or is it pretty much wide open and impossible to predict?
|
Like say in 3, 30, or 300 million years from now, could primates surpass the intellect of modern humans and grow into a new society? Could dolphins become amphibious and eventually develop claws or fingers for grasping tools?
|
askscience
|
http://www.reddit.com/r/askscience/comments/n5e83/are_there_any_theories_on_the_future_of_evolution/
|
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"At the scale you are interested in evolution is impossible to predict. The fundamental principle of evolution is that organisms change as a result of random changes. \n\nThere is no means to forecast what mutations will occur. Even if you could forecast where and when a mutation would occur you have no way to know how the resulting change will interact with the environment of the organisms (the phenotype). There is also the further effect of genetic drift, where random effects external to the genome affect the abundance of different genetic types in a population. Drift can result from small things, such as being born into a population where a particular nutrient is slightly less abundant than ideal, lowering fitness, all the way up to events like floods and earthquakes, which might wipe out a species completely by chance.\n\nNow, at a finer scale there is a possibility that in the near future we will be able to make probabilistic models that can be used to simulate evolution. Proteins are sequences of amino-acids, and for each protein sequence there is only so many ways they can change into another sequence based on step-by-step evolution of genes. As our understanding of the energetic and biological constraints of protein structure grows we should be able to predict the likely function of mutant proteins, the likelihood they have to mutate to that form from a current form, and the overall probability that such a protein might be evolutionary fitter in a given (and highly contrived) system. Unfortunately, much beyond this becomes impossible, because the complexity of the systems, and the number of random variables rapidly becomes incalculable.\n\nThe only general prediction you can make about the future trajectory of our species is that we probably will not be around for ever (well duh!). Based on estimates [of the background extinction rate](_URL_0_) mammal species only last for about 1 million years. That said, humans are pretty unlike any species that has ever existed before us (as far as we know) and so I suspect we will probably wipe ourselves out long before the gradual process of evolution moves us on to a novel and distinct form.\n\n**TL:DR** No, it is impossible to predict",
"Evolution is based on random mutations. Although the selection pressures on certain traits aren't random, the ones that evolution \"tries\" are.",
"\"Nothing endures but change.\" Heraclitus\n\nOne thing I can absolutely predict, humans will not be the dominant species in 3, 30, or 300 million years. Though it is possible that some species related to us or derived from us will be dominant.",
"At the scale you are interested in evolution is impossible to predict. The fundamental principle of evolution is that organisms change as a result of random changes. \n\nThere is no means to forecast what mutations will occur. Even if you could forecast where and when a mutation would occur you have no way to know how the resulting change will interact with the environment of the organisms (the phenotype). There is also the further effect of genetic drift, where random effects external to the genome affect the abundance of different genetic types in a population. Drift can result from small things, such as being born into a population where a particular nutrient is slightly less abundant than ideal, lowering fitness, all the way up to events like floods and earthquakes, which might wipe out a species completely by chance.\n\nNow, at a finer scale there is a possibility that in the near future we will be able to make probabilistic models that can be used to simulate evolution. Proteins are sequences of amino-acids, and for each protein sequence there is only so many ways they can change into another sequence based on step-by-step evolution of genes. As our understanding of the energetic and biological constraints of protein structure grows we should be able to predict the likely function of mutant proteins, the likelihood they have to mutate to that form from a current form, and the overall probability that such a protein might be evolutionary fitter in a given (and highly contrived) system. Unfortunately, much beyond this becomes impossible, because the complexity of the systems, and the number of random variables rapidly becomes incalculable.\n\nThe only general prediction you can make about the future trajectory of our species is that we probably will not be around for ever (well duh!). Based on estimates [of the background extinction rate](_URL_0_) mammal species only last for about 1 million years. That said, humans are pretty unlike any species that has ever existed before us (as far as we know) and so I suspect we will probably wipe ourselves out long before the gradual process of evolution moves us on to a novel and distinct form.\n\n**TL:DR** No, it is impossible to predict",
"Evolution is based on random mutations. Although the selection pressures on certain traits aren't random, the ones that evolution \"tries\" are.",
"\"Nothing endures but change.\" Heraclitus\n\nOne thing I can absolutely predict, humans will not be the dominant species in 3, 30, or 300 million years. Though it is possible that some species related to us or derived from us will be dominant."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Background_extinction_rate"
],
[],
[],
[
"http://en.wikipedia.org/wiki/Background_extinction_rate"
],
[],
[]
] |
|
1x2c1p
|
why do cold sores sting?
|
Well, first of all, my original thought was why do they sting when I rub my tongue over them, but after taking a drink of water just now I realized pretty much anything that touches it stings.
Why is that?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1x2c1p/eli5why_do_cold_sores_sting/
|
{
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"text": [
"Herpes actually infects the nerves themselves, so it's a combination of direct stimulation of the pain nerves and stimulation by swelling."
]
}
|
[] |
[] |
[
[]
] |
|
e05rlm
|
what causes the full body twitches during climax?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/e05rlm/eli5_what_causes_the_full_body_twitches_during/
|
{
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"text": [
"Are you guys getting full body twitches?",
"[Article](_URL_0_) about the hormones released and the brain activity during orgasm.\n\nThe answer is that almost the entire brain \"lights up\" with activity and neurons triggering, and your blood is flooded with dopamine (feel good hormone) and oxytocin (hormone of attraction to the other person). This \"increased activity\" effect includes the motor cortex (area of the brain that controls muscles)."
]
}
|
[] |
[] |
[
[],
[
"https://www.sciencealert.com/here-s-what-happens-to-your-brain-when-you-orgasm"
]
] |
||
6fjwb6
|
How did people think magic was real?
|
I'm mostly picturing medieval time. Was there a court wizard or something like it? What WAS magic back then.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/6fjwb6/how_did_people_think_magic_was_real/
|
{
"a_id": [
"diiycbv",
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"text": [
"Depends on the time frame and geographic location, but it's important to remember that for pretty much the entirety of human existence, people have believed in magic - even today, people have their luck rituals, check their horoscopes, or drink potions designed to make them healthier or more attractive (we might call it a \"cleanse\" today, or herbal supplements, but it's the same basic thought process); folks might call the psychic hotline rather than consult a chiromancer, but it's still essentially magical thinking.\n\nThere were *very generally speaking*, two \"classes\" of magicians: cunning folk and scholastics. By \"cunning folk\" I mean the professional or semi-professional wise men and women that peasants and townsfolk might resort to find lost goods, heal sick cattle, dowse for water or treasure, etc. or else pay off to lift a curse or avoid the evil eye. \"Scholastics\" by contrast would use \"learned magic\" and range from petty clerics performing exorcisms and conjurations for pay, to alchemists, lawyers, and doctors playing with grimoires, image magic, or the supposed supernatural properties of objects; you're mostly looking at the clergy, more educated cityfolk, and nobility. \n\nTwo really great sources for understanding those different magical traditions, what they did and how they came to be associated, are Owen Davies' [Grimoires: A History of Magic Books](_URL_0_) and [Popular Magic: Cunning-Folk in English History](_URL_1_).\n\nSo, \"magic\" could be a lot of things in a number of different contexts, and the definition of what it was, what it could accomplish, and how were substantial questions in the medieval world - especially to ecclesiastical authorities, who were concerned with charges of sorcery and heresy, which would later flare up into the European witch-trials.\n\n > **Was there a court wizard or something like it?**\n\nNot often *explicitly*, but Edward Peters notes in [The Magician, The Witch, and the Law](_URL_2_):\n\n > It has been said of the court of Louis the pious, son of Charlemagne, that every great man at it had his own personal astrologer. The texture of Carolingian court life suggests the plausibility of this remark, because in the heady atmosphere of transforming an Iron Age assembly of warbands and settlers into an ideal Christian kingdom, the Carolingian Empire often presents (as it did to itself) the image of a composite of late Roman imperial and barbarian Germanic styles of life and thought. the classical works that Carolingian scholars discovered, edited, and circulated among themselves were the very ones that managed to preserve much antiquarianism along with Christian piety. The religious basis of Charlemagne's and Louis's *renovatio* has long been recognized. What has often not been recognized as fully is how much of the old learned world of late antiquity came with the Christian materials. In the sophisticated, learned, violent, and self-serving Carolingian court world those who had access to, and even a rudimentary understanding of, learned magic could easily find employers. No residual pagan superstitions or folk beliefs were necessary. The Carolingian aristocrats knew how to value learned magicians as it valued learned chroniclers, holy men, astrologers, wandering Irish scholar monks, and any other successful means of making their way through the rapidly changing post-tribal world of Charlemagne's renewed Roman Empire and Louis's rapidly deteriorating Christian kingdom.\n\nFrom a literary standpoint, the figure of Merlin in the Grail Romances would have informed and fulfilled some of the medieval conceptions of a \"court magician,\" and I could probably dig up other examples. Even if not formally holding a position at court, the concentration of money and politics often created a demi-monde were magicians could thrive; in 17th century France for example (I know, a bit out of your chronological range), you had characters like La Voisin, who reputedly peddled poisons, love potions, abortions, fortune-telling, and black masses to the royalty of the court of Louis XIV.\n\n\n",
"The esteemed /u/AncientHistory did his/her typically extraordinary job addressing this question. From a folklorist's point of view, an understanding of pre-industrial magical practices is based on ethnographic work. It is then possible - with care and source criticism - to extrapolate that some of these these or similar practices occurred in earlier times including the medieval period. Medieval primary sources support some of these conclusions. The following is an excerpt from my [Introduction to Folklore](_URL_1_) dealing with this, including material drawn directly from my mentor's - [Sven Liljeblad](_URL_0_) Introduction:\n\n > One of the best examples of a comprehensive look at belief and custom is the Handwörterbuch des deutschen Aberglaubens (Encyclopedia of the German Popular Superstitions), which appeared in nine volumes between 1927 and 1942. This is an exceptional work because it offers published material that most folklore archives only possess in unpublished form. A similar publication includes a wide variety of material from the Finnish collection: Suomen kansan muinaisia taikoja (Old Magic Practices of the Finnish People), which appeared in eight volumes between 1891 and 1934. The final three volumes provide an example of the degree of detail possible. There are roughly 20,000 elementary ideas and their variants concerning the magical practices associated with cattle.\n\n > In short, it would be possible to become lost in the detail. Nonetheless, an overview of various forms of belief and customs can be beneficial.\n\n > For European peasants (if not for non-industrial people in general), the world was filled with the supernatural and its potential. They believed that a wide variety of supernatural beings came and went freely about the world. This could occur any time, but nighttime, special days, and specific locations could require extra precaution. People also believed that there were magical practices one could and should undertake to protect oneself and to manipulate the supernatural to prevent calamity or to eke out a better existence. Two examples demonstrate that some traditions survive both industrialization and immigration. North Americans preserve the preventative practices of knocking on wood and throwing spilled salt over one’s left shoulder (although the latter is becoming less common). Both acts were to distract the supernatural from doing harm. \n\n > Traditionally, Europeans used magic in various minor ways. Expert practitioners developed the generally-accepted techniques and beliefs into a refined craft, but they did not deviate from the core beliefs of their culture. Liljeblad, in his Introduction to Folklore, uses ten categories to group the rules of magic. They are as follows:\n\n > 1 Bodily dimensions and movements: There are choices one can make involving front and back and left and right. The front is positive, and the back is negative. Movements forward and backward have positive and negative values, respectively.\nSimilarly, the right hand and movements to the right are positive, and those involving the left are negative. By analogy, clockwise, a movement involving left to right, is positive and counterclockwise is negative. The direction of the sun in the Northern Hemisphere reinforces the basic assumption that left to right is the natural motion of the world.\n\n > The belief in the importance of front and back and left and right inspired day-to-day practices involving the supernatural and it dominated formal magical practices. The back of the house was particularly vulnerable to the supernatural. It required special magical attention in the form of painted symbols or other magical practices to thwart possible dangers. Movements backwards were considered evil. Parents told children not to walk backwards because they would “drag father and mother to hell.” A person taking a few steps backward would be told “you go wrong.”\nAlong these lines, cooks stirred food clockwise, and they cut and served from left to right. If someone turned his hand counterclockwise, he needed to turn his hand an equal number of times clockwise to undo the harm. In the same way, popular warning discouraged twisting one’s thumbs around – what is called “twiddling one’s thumbs” – toward oneself. They should rotate in the opposite direction. Custom forbid dancing counterclockwise, an act that would inspire the warning, “You dance against the sun. Turn around.”\n\n > The right hand has traditional preference over the left, a fact reflected in language and practice. The idea that one should begin the day with the right foot out of the bed is echoed in the phrase, “he got out of bed on the wrong side today.”\n\n > All this resulted in day-to-day activities that respected the perceived natural order of the world and its preference for front over back, right over left, and clockwise over counterclockwise. When wishing to manipulate the supernatural, however, the patterns were typically reversed. The left hand as well as backwards and counterclockwise motions gained importance. Walking backwards and counterclockwise around a church three times could give the power to see the future. The same act around a well, combined with throwing an object representing an illness, backward over one’s left shoulder into the well, could restore health. A silver coin in the left shoe protected against evil.\n\n > These practices could quickly step into the sinister realm. Magical potions were stirred counterclockwise, particularly if something hurtful was sought. The Stations of the Cross are arranged clockwise within a Catholic church. Walking counterclockwise inside a church, backwards, then reciting the Lord’s Prayer backwards at the rear of the church with one’s back to the altar was sufficient to call up the devil.\n\n > By analogy with the idea of front and back, one avoided turning things upside down or inside out unless there was a specific need or desired result. When walking home in the dark, it might be wise to pull one’s pockets out as a barrier against elfin attack. An intrepid soul might wear a coat inside out, thus acquiring supernatural sight to see the elves. This was not recommended since the supernatural beings frequently punished such audacity. The same act could produce different results, as described in legends, depending on the motive of the protagonist.\n\n > 2 The Cardinal Points: The origins for the terms east, west, south, and north hint at an ancient posture facing east with the left side of the body to the north, the right to the south, and the back to the west. Even the word “orientation” descends from a Latin word for sunrise, and hence the east. It appears that facing east has had premier importance for centuries if not millennia, particularly when dealing with the supernatural. Most cultures share this point of view. Traditionally churches situated the altar at the east side of the long axis so that the congregation faced in that direction to view the priest and the Elevation of the Host.\nThe idea of facing east gave each direction a specific meaning. East (front) and south (right) had positive value, while the contrasting west and north were negative. North was a direction of disaster and unhappiness. Diseases, for example, could be magically discarded in rivers that flowed north. In medieval Scandinavia, the land of death was to the north. For the Irish, Tir na nOg, the land of everlasting youth (and death), was to the west. In Arthurian literature, King Arthur goes west to Avalon after receiving his mortal wound. The power of this direction gave meaning to the western islands that eighth-century Celtic monks inhabited as they awaited their final meeting with God.\n\nThere are eight more of these items - so posting all of this could be tedious. But you get the point."
]
}
|
[] |
[] |
[
[
"http://www.worldcat.org/title/grimoires-a-history-of-magic-books/oclc/781239916",
"http://www.worldcat.org/title/popular-magic-cunning-folk-in-english-history/oclc/484694769",
"http://www.worldcat.org/title/magician-the-witch-and-the-law/oclc/36179703"
],
[
"http://www.onlinenevada.org/articles/sven-s-liljeblad",
"https://www.amazon.com/Introduction-Folklore-Traditional-Studies-Elsewhere/dp/1521423261/ref=sr_1_1?ie=UTF8&qid=1498305943&sr=8-1&keywords=Ronald+M.+James"
]
] |
|
29n3mh
|
Good sources on the Russo-Japanese Wars?
|
Pretty much as per the title, I've recently become interested in the numerous conflicts between Russia and Japan, up to and including World War II. I tend to have trouble getting my way through books that are too dry, so I'd like to request good prose over the level of detail if I can't have both (of course, not at the sacrifice of accuracy).
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/29n3mh/good_sources_on_the_russojapanese_wars/
|
{
"a_id": [
"cimiv1d"
],
"score": [
7
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"text": [
"Had to dig back into my university reading lists to find exact titles, but here's a couple I remember being useful reading on Japanese imperialism in the late 19th/early 20th century:\n\n* W.G. Beasley, *[Japanese Imperialism, 1894-194](_URL_0_)5* (1987) \n* Myers & Peattie, eds., *[The Japanese Colonial Empire, 1895-1945](_URL_3_)* (1984)\n\nFrom the Russian angle, see:\n\n* Wolff & Steinberg, *[The Russo-Japanese War in Global Perspective: World War Zero](_URL_2_)* (2007)\n* David Schimmelpenninck van der Oye, *[Toward the Rising Sun: Russian Ideologies of Empire and the Path to War with Japan](_URL_1_)* (2006)\n\nAs a general source on the 1905 war that's useful if a little aged now, have a look at:\n\n* Dennis & Peggy Warner, *[The Tide at Sunrise: A History of the Russo-Japanese War, 1904-1905](_URL_4_)* (1974)\n\nHope that's of some use."
]
}
|
[] |
[] |
[
[
"http://books.google.co.uk/books/about/Japanese_Imperialism_1894_1945.html?id=Ik4mclWXq7cC&redir_esc=y",
"http://books.google.co.uk/books/about/Toward_the_Rising_Sun.html?id=nVVOAAAACAAJ&redir_esc=y",
"http://books.google.co.uk/books/about/The_Russo_Japanese_War_in_Global_Perspec.html?id=xlg0lM8f9Y4C&redir_esc=y",
"http://books.google.co.uk/books/about/The_Japanese_Colonial_Empire_1895_1945.html?id=KqNiaX7b4bgC&redir_esc=y",
"http://books.google.co.uk/books/about/The_tide_at_sunrise.html?id=FeXSvEv5EjgC&redir_esc=y"
]
] |
|
5sf577
|
How free was Venetian society?
|
Given that most regions of Europe were very feudal, and most people were dirt-poor serfs with few rights, how did Venetian society compare? It was a "republic," as well as a massive trade hub. Did this have any effect on the quality of life/level of freedom for the average citizen?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5sf577/how_free_was_venetian_society/
|
{
"a_id": [
"ddgcmt8"
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"score": [
7
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"text": [
"John Julius Norwich opens his *History of Venice* by noting that more time separates the beginning and end of the Republic of Venice than separates Queen Elizabeth II of England from the Norman Conquest. The Republic of Venice was a polity which existed for ove a thousand years, outlasting two and a half polities calling themselves \"Kingdom of Italy,\" and witnessing the beginning, middle, and end of feudalism. The Republic saw the rise of the nation state, and was extinguished just prior to the creation of an Italian national identity. As the Republic grew and changed over time, so did its government and institutions; so there can be no single answer to this question. However, this question can be answered by examining the inclusiveness of Venetian institutions over time. \n\n**Part One: The Origins of the Venetian Political System**\n\nThe early history of Venice was fundamentally characterized by the constant threat of revolt. Already in the eighth century, under Byzantine rule, the people of the lagoons had risen up against an imperial decree they disagreed with. Perhaps as a consequence of the Northeastern Italian coast's geography, in late antiquity the people of the Lagoons quickly became rich, numerous, and influential. One chronicle attests that when St. Mark's body was stolen from its resting place in Alexandria in 832, no less than ten Venetian ships were present in the harbor. Because of the importance of navigation in the economy (and the fact that Venice started out as a bunch of islands in a lagoon) Venice never developed a strong landowning aristocracy like the rest of the former Roman Empire and instead developed a system of government in which the people acclaimed one person to organize the protection of the lagoons. \n\nCoastal northeastern Italy was a Byzantine Military outpost up until Ravenna fell to the Lombards in the eight century. When Ravenna was under siege in 751, no Consul was appointed to govern the lagoons that year. The people elected their own *Dux*, or military leader (a title which would quickly be corrupted in the local Vulgate to \"Doge\"). When Ravenna fell and what was left of the Byzantine army evacuated to Bari, this man (named Teodato Orseolo) found himself the ruler of an independent polity. Never having officially severed ties with the Eastern Empire, Venice existed in a legal of gray area for its early history. In Basileus Nicepherus' 811 treaty of recognition with an elderly Charlemagne, Venice is recognized as a sort of self-governing Byzantine commonwealth. Early Venetian rulers would adopt multiple Byzantine titles. However, there was no way for the Eastern Empire to enforce their rule; for all intents and purposes, Venice was an independent state.\n\nThe lack of a powerful landed aristocracy didn't mean that early Venetian society was some sort of happy Star Treck kind of equal society. In fact, in the ninth century Venetian citizens were split between the pro-Byzantine landowners in Eraclea, the pro-Republican merchants of Malamocco, and the pro-Frankish Clergy. The Doge was elected by popular acclaim (often, a particularly wise and well-liked citizen was elevated by the populace) and the Doge was checked by two high judges called Tribunes, typically one from the Island of Malamocco and another from the community of Eraclea. \n\nI'm not going to go through every single decision that was made (generally, after every few revolts a new office was created) however some important dates stand out: in 1143 a *Concilium* or council was established to represent the people, replacing the *Arengo*, a word basically connoting the Venetian mob. \n\nBy the twelfth century, the Venetian Republic was facing several internal and external pressures; this was a time period when most Italian Cities were affirming their new independence by rallying around urban Bishops. However, Venice had always been independent and had no need to rally around their Bishop, who happened to hold the very important title of Patriarch of Aquileia. In fact, the Venetians not only insisted on taking an independent line between the Church and the Italian cities in their fight against the Holy Roman Empire, but even actively ignored the conflict; preferring to focus energy to help the Byzantine Empire fight a war against the King of Sicily. Further, several venetian trade outposts in Dalmatia were no longer acknowledging Venetian rule.\n\nManaging relations with an increasingly active and politicized clergy, a state of war just over the lagoon on the Italian mainland, Venice's own war in Sicily, and the pacification of the Istrian cities, could no longer be performed solely by the Doge and his inner circle of friends and advisors. So his inner council was replaced the 35-man *Concilium*, who would function as the Doge's ministers and council, with all members acclaimed for life by the *Arengo*. \n\nBy 1207, population growth made assembling the Venetian mob every time a Councilor dropped dead went from being impractical to being almost impossible. So instead of nominating each member of the *Concilium*, they nominated three \"Electors\" whose job it was to pick men to serve in the *Concilium*. In 1230, the mob started acclaiming however many wise men they thought were sufficient to pick a suitable council, sometimes picking as many as seven electors.\n\nIn the meantime, the government of Venice grew. The *Concilium* was increased to 100 members in 1172, effectively constituting a state bureaucracy. By 1178, the Doge was no longer elected by the *Arengo*, but by the *Quarantia*, forty men who constituted Venice's highest judicial body. These forty were nominated by seven electors, aclaimed by the *Arengo*.\n\nParticipation in the *Concilium* became hereditary in 1297, in an event called the *Serrata*, or \"Sealing\" of the council. The high judges of the *Quarantia* composed a list of families they considered \"Acceptable\", and each was allowed to send their male members over the age of 25 to the council. The *Consilium* ballooned from one hundred to one thousand members, and became the legislature of the Republic. "
]
}
|
[] |
[] |
[
[]
] |
|
2ulphg
|
Are Hitler and Wittgenstein in this photo?
|
_URL_0_
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2ulphg/are_hitler_and_wittgenstein_in_this_photo/
|
{
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"coapet1"
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"text": [
"I'm of the opinion that it is not. Wittgenstein and Hitler did attend the same school in Linz but the photo is dated to a time when Wittgenstein might not have been at the school. Also Hitler and Wittgenstein would have been two grades apart, which would make it odd for them to appear together in what appears to be a class photo.\n\nYou may or may not be aware that Wittgenstein and Hitler possibly knowing each other in school was the subject of a book, \"The Jew of Linz\". The link below covers the photo and the arguments for and against it being Wittgenstein in the same photo:\n\n_URL_0_\n\nThe argument in favour seems to be the author's claim that he had the photo checked out by Australian state police and they agreed. I haven't read the book but I express doubt that it is quite as straight forward as that. I've worked in the Victorian public service and I doubt the Police would do a 'job' for an author, I'm not even sure they would have assisted if they had been asked by a university - it would have to have come from the government. Also I'm reluctant to believe that there was a dedicated photographic analysis unit, I think that would fall under more generalist forensics units rather than having one unit that does nothing but analyse photos. What I'm getting at is made whoever looked at this photo wasn't quite the master/expert the author claims."
]
}
|
[] |
[
"http://www.aryse.org/wp-content/uploads/2012/02/realschule.jpg"
] |
[
[
"http://en.wikipedia.org/wiki/The_Jew_of_Linz#Realschule"
]
] |
|
3uvyv4
|
Was Greece's successful defense against Italy really a crucial factor for the win of the Allied forces at World World II?
|
So, I live in Greece, and the following is something that's heard a lot in History classes: because the Greek pushed back the Italians when they attacked Greece, the Germans had to come to finish the job and conquer Greece, and the delay caused by this resulted in Germany invading Russia during the winter, which led to eventual loss of a big part of their army in the Battle of Stalingrad, which was the turning point of the war. Is this true, partially true, or just completely false?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3uvyv4/was_greeces_successful_defense_against_italy/
|
{
"a_id": [
"cxi8xkj"
],
"score": [
7
],
"text": [
"From an earlier [answer](_URL_0_) \n\nThis is a somewhat contentious issue and one that is clouded by numerous parties postwar who argued that the Greek theater was a vital delay for Barbarossa. Obviously, the notion of Greek resistance and a nationalist narrative fed into the delay hypothesis, but it also received support from British quarters who argued that the deployment of W Force was not a waste of lives, but a vital delaying action. Postwar German generals also popularized this narrative. Keitel would claim postwar the Greek adventure was a \"great delay,\" without which \"events on the Eastern Front\nand the war as a whole would have turned out very differently.\" \n\nThe strongest support for each of these narratives is that Barbarossa was initially set to commence in mid-May but later got pushed back to June. Planning for Operation *Marita* ran concurrently with planning for Barbarossa and the growing concerns with occupying the whole of the Balkans led to a deployment of troops needed later for Army Group South's invasion of the southern USSR. However, there is not a straight line between Greece and the June date as there were other factors behind the delay. The spring rains created concerns within both OKW and OKH about the viability of a May invasion. Guderian would later claim postwar that he had personally reconnoitered the Bug River and found them passable and the actual meteorological data for 1941 shows that rainfall was not above average in the various marshaling points for the German invasion. Nevertheless, this was a viable concern for German planners as an unexpected storm could bog down an invasion before it started. The need to train and reequip formations was another pressing factor for German planning. Even though the Germans went about planning for the invasion with an almost cavalier attitude to Soviet capabilities, they could not escape the material constraints of equipping an army for such a vast undertaking. For any planner in OKW and OKH that wanted a delay to better prepare for Barbarossa, *Marita* was a godsend as it provided an overwhelming justification for pushing back Barbarossa until a time that it was more manageable for German forces. \n\nThe issue of the delay possibly caused by *Marita* has overshadowed the actual benefits that Germany accrued from invading Greece. Firstly, it secured Germany's southern flank and prevented the British from operating against Romanian oilfields while German forces were preoccupied with the USSR. The swift invasion of Yugoslavia also helped cow Germany's Eastern European allies like Hungary who were not that enthusiastic about participating in the grand crusade against communism. Secondly. *Marita* helped Barbarossa achieve a degree of strategic surprise. A number of Soviet intelligence forces initially warned that the deployment of German troops to the Balkans was the start of a larger invasion of the USSR. Although Soviet troops went on alert, they found there was no invasion forthcoming. This \"boy who cried wolf\" mentality did play a role in the dismissal of later German preparations for Barbarossa. The deployment of German troops to the Balkans created much confusion as to what Germany's true strategic aim was, especially in light of overtures to Turkey, German involvement in the Iraq coup, and the creation of DAK, all of which might have suggested a broader German strategic reorientation to destroy the British in the Mediterranean. \n\nBut *Marita* did degrade German military capabilities in several significant ways. Aside from occupation costs, the troops involved in Greece arrived late to the Soviet campaign and their equipment was worn-down. Army Group South lost six infantry divisions in the opening stages of Barbarossa because of *Marita*. This left a number of the initial attacks understrength and more reliant upon Romanian and Hungarian contingents than their neighbors. Both of these satellite armies emerged out of Barbarossa in quite rough shape because they had to conduct operations that were outside their capabilities. This combat degradation continued over the long-term and would come back to haunt the Germans when they were dependent upon the minor Axis powers to guard the Stalingrad salient in the campaign the next year. \n\nThe invasion of Crete also cost the Germans dearly in terms of transport aircraft and soured German planners on the use of airborne troops. There were some tentative plans to close off the encirclement of Soviet troops with airborne forces, but the losses incurred in *Merkur* precluded this. Perhaps more importantly, the loss in transport aircraft further hobbled a German airborne logistical force that already was inadequate for the task at hand. The Germans had pioneered a number of elements of resupply by air in *Fall Gelb*, but this was less viable in light of German losses to take the island. The Luftwaffe was able to cobble together enough forces in Barbarossa to resupply over-extended lines, most notable at Demyansk and Kholm, but could only do this by stripping training units back in the *Reich*. This short-term expedient was problematic for the Luftwaffe's transport forces which by 1942 was operating at a negative ration with losses in aircraft outstripping their resupply by a ratio of approximately 2:1. \n\nIronically, one of the most central planks of the delay hypothesis itself rests on a set of highly dubious propositions. The basic idea is that the month's delay meant that German forces might have reached Moscow one month earlier and captured it before the onset of winter. British General Henry Wilson, the commander of W Force, would tell a group of repatriated British and Commonwealth POWs in 1943 that \"Greece was responsible for the six weeks’ delay which allowed the winter to intervene.\" Although \"General Winter\" remains a popular trope even in 2015, it is one historians of the Second World War have long since discarded as a significant factor in Germany's failure to defeat the Soviets in 1941. German forces were simply too small and inadequate to complete the job and the Soviets were able make good their tremendous losses through a herculean effort that few expected in 1941. Nor was the occupation of Moscow the plum strategic target that some postwar commentators claim; although the loss of the capital would have been a blow to prestige and some hindrance to the Soviet war effort, it was not central to the Soviet war economy. The Stalinist industrialization drive of the 1930s allowed for excess productive capacity and it could have adjusted to the loss of Moscow just as it did with the loss of other Soviet cities. \n\nSo while Ochi Day and the valor of Greek resistance is something for Greeks to be rightly proud of, the impact of *Marita* on the larger German war effort was pretty peripheral. It added an extra burden on an already overtaxed German military establishment and gave a pretext for a delay that German planners were already floating. \n\n*Sources*\n\nCitino, Robert Michael. *Death of the Wehrmacht: The German Campaigns of 1942*. Lawrence: University Press of Kansas, 2007. \n\nMilitärgeschichtliches Forschungsamt, *Germany and the Second World War, Volume III: The Mediterranean, South-east Europe, and\nNorth Africa, 1939- 1941* Oxford: Clarendon Press, 1995.\n\n_. *Germany and the Second World War. Volume IV, The attack on the Soviet Union*. Oxford: Clarendon Press, 1998. \n"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/3qedk0/it_took_six_months_for_the_axis_powers_to_force/"
]
] |
|
1370ey
|
Is it coldest before dawn, or am I ... feeling things?
|
So, I've always noticed that it is coldest before the sun comes up, but I'm curious whether this is:
1) a function of basic physiology whereby my circadian rhythm is tied to sensory perception that is more acute when nearing a waking state.
2) a function of psychology whereby I am more aware of my senses the nearer I am to a waking state.
3) a function of thermodynamics I don't understand.
4) a function of time whereby the time before dawn is the longest my body has been without an ambient heat source.
5) ... something else entirely?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1370ey/is_it_coldest_before_dawn_or_am_i_feeling_things/
|
{
"a_id": [
"c71cjix",
"c71d7f7"
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"score": [
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6
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"text": [
"If you're in the US, check out _URL_0_. They have a great temperature graph that tracks temperature as time of day along with sunrise/set.\n\nThe other day, in Iowa, the high temperature for that day was in fact, midnight as the day began, in the low 70s. A cold front moved in and continued to cool off, so just before dawn was in fact warmer than the rest of the day to follow.",
"Typically the coldest part of the day is a short time *after* the sun has come up, because the temperature is still dropping but less quickly now that there is a solar energy source. So the bottoming-out usually occurs a bit lagged with respect to sunrise. Though it might not feel that way, since you can gain some radiative heat from the morning sunlight right away, without waiting for the sun to heat the earth and have the effect percolate up through the atmosphere."
]
}
|
[] |
[] |
[
[
"www.weather.gov"
],
[]
] |
|
2y7aaw
|
why is the underlying algorithm used to calculate credit scores not in the public domain?
|
I realize that there are plenty of high-tier explanations for what factors influence one's credit (e.g., 35% comes from payment history, 15% length of credit history...) but the actual algorithm is protected IP for reporting agencies. Wouldn't a more transparent system work better and encourage clear **actionable** improvements for a borrower's habits?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2y7aaw/eli5_why_is_the_underlying_algorithm_used_to/
|
{
"a_id": [
"cp715xz",
"cp7515i"
],
"score": [
3,
2
],
"text": [
"The United States has the rule of law, more or less. \n\nWe don't just arbitrarily confiscate people's property, including intellectual property, because some guy on the internet thinks that that would be more fair.",
"ex credit report resale IT guy here... I can attest that at least part of the reason is the complexity, not only of each bureau's calculation, but of the interaction among the main 3 (equifax, experian, and transunion) as well as resellers and agrigators of the output from the big three\n\neven as partners and clients of the bureaus, the best the company I worked for had was a photo copy of a photo copy of a 20-year-old spec document from one of the bureaus that I don't think we were even supposed to have and even that was barely legible and had annotations made along the way \n\nI suspect they're not actually able to provide a 100% accurate formula if they wanted to... not that they shouldn't, but it's decided by a ton of old code written by people who don't work at the companies anymore and that no one touches for fear of bringing the whole thing crumbling down... "
]
}
|
[] |
[] |
[
[],
[]
] |
|
6gk83f
|
What philosophy/methodology is there to historical analysis?
|
Is there a specific methodology/philosophy that Historians use when analyzing why certain events in history happened the way they did? Due to my own political beliefs I follow Dialectical Materialism which is what we use to say why x event happened the way it did and can be used to explain the fall of feudalism and the rise of capitalism, certain trends within recent history like the rise of fascism and socialism, etc. If historians aren't using this as their "lens" of viewing the world and using it as an explanation of why things happen the way they do then what are they using?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/6gk83f/what_philosophymethodology_is_there_to_historical/
|
{
"a_id": [
"dir8umf"
],
"score": [
3
],
"text": [
"I don't want to discourage other answers, but I think [this thread](_URL_0_) may be in the neighborhood of what you are looking for. Provided, of course, that I've understood your question correctly. Basically, the thread goes into some detail regarding Great Man Theory, Trends and Forces, and how historians going about writing history."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/68ma5k/monday_methods_on_great_man_theory_trends_and/"
]
] |
|
160vxt
|
What is the significance of the ~28 day menstrual cycle in humans?
|
I understand all mammals have varying cycles, but I was curious if their were any theories or evolutionary benefits for human to have the cycle we do.
Kind of a strange question, I know, but just my random pondering on a Saturday afternoon.
|
askscience
|
http://www.reddit.com/r/askscience/comments/160vxt/what_is_the_significance_of_the_28_day_menstrual/
|
{
"a_id": [
"c7rmx4n",
"c7rnkx8"
],
"score": [
2,
6
],
"text": [
"[not layperson speculation, but a request for clarification] \n\nDo you mean is it significant that its about the same length as a month? Are you comparing significance to mere coincidence? ",
"I just watched the show QI, so I have this big echoing voice in my head that goes \"Nobody knows! (knows ... knows ... knows ..)\". There are a lot of theories out there, and a lot of passionate supporters of said theories, but we really don't know. One thing that can be said with reasonable confidence is that it is not related to the lunar cycle. The average menstrual cycle is not 28 days, and the studies that I was working on in college suggested that it was closer to 27.25 days. The statistical data showed that the discrepancy between the lunar cycle and the average menstrual cycle was significant enough to determine that there was no linkage. Currently a lot of evolutionary biologists believe that females used to go into heat and be fertile for one period during the year, lasting possibly up to 3 months. At this point the breasts would enlarge and woman would release eggs. At some point evolution may have favored women that appeared fertile or actually were fertile for a much larger portion of the year. Breasts stayed enlarged and menstrual cycles sped up. 27.25 days may just be the shortest cycle that allows women to still have a healthy start to pregnancy as often as possible. Like I said, there are tons of theories. One theory states that humans were polygynous (more than one female per male, and is most likely true) and that being able to reproduce whenever a new male took over was advantageous instead of only being able to reproduce once per year and having to count on a steady male presence for that long."
]
}
|
[] |
[] |
[
[],
[]
] |
|
3ahy7j
|
are there nuclear reactions that give out hydrogen (proton or deuteron) as a product?
|
With some friends we were discussing terraforming of planets poor in light elements (Venus). My idea being that it would be easier to produce these elements in loco rather than move huge amounts through the solar system.
|
askscience
|
http://www.reddit.com/r/askscience/comments/3ahy7j/are_there_nuclear_reactions_that_give_out/
|
{
"a_id": [
"csdh9ti"
],
"score": [
2
],
"text": [
"Hydrogen, or more specifically a proton, can be emitted during very rare nuclear decay events. It would be entirely impractical to use this, or any sort of radioactive element, to populate an entire planetary quantity of another element.\n\n[Here](_URL_0_)"
]
}
|
[] |
[] |
[
[
"https://en.m.wikipedia.org/wiki/Proton_emission"
]
] |
|
1c9ilk
|
Looking for information on "The Last Africans" (book).
|
Hi, on my travels in Ghana a host showed me this book documenting the last African tribes living "pure" traditional African lifestyles. It's from the late seventies, I forgot the author (sorry), but [Amazon suggests G. Chesi](_URL_0_) - kinda hard to tell for sure without description and cover picture.
My questions:
* There was a story in there about one tribe that resisted being forced off their land by the British, and at the time the book was written a *biologist* had recently discovered why: the land they were assigned was a valley that *looked* fertile, but was lacking in crucial minerals for their livestock to get nutrition from the grass there. The tribe knew this, but the British didn't listen to their stories. I'd like to read that paper, but because I don't remember the name of the tribe, biologist or even nation in which it took place I can't find it. Also, I'm quite curious if there are documented cases with other native people similar to this one (this is why I ask here even though the book is more anthropology than history).
* While we're at it: suggestions for other books like it. Does not have to be limited to African culture - anything non-Eurocentric has my interest, really.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1c9ilk/looking_for_information_on_the_last_africans_book/
|
{
"a_id": [
"c9edmwo"
],
"score": [
2
],
"text": [
"I've found a review of *The Last Africans* by Gert Chesi in *Africa: Journal of the International African Institute*, Vol. 53, No. 3 (1983), pp. 99-104:\n\n > *The Last Africans*, by Gert Chesi, is also a 'coffee-table' book, but very different from\nBamert's 'art-object'-oriented one. It is lavish in the extreme, the layout spectacular, the\nphotographs superb - including portraiture, landscape, architecture, market-places, and\npeople at work, at rest, and engaged in rituals. Basically this is a book of 'art photography', so\nthat the landscape and architecture becomes 'art' and the people themselves become 'art\nobjects'.\n\n > The style is colourful, but with many inaccuracies, inconsistencies and generalizations that\nare too often shallow, platitudinous and patronizing. Ten different peoples are selected to\nexemplify the 'last Africans' of a 'legendary unconquerable continent', people who are\n'unspoiled by other cultures and who have retained their natural way of life and still adhere to\ntheir traditional heritage' (p. 211). Yet most of the people chosen have either adopted many\naspects of European life-styles or live in European tourist villages with scheduled sightseeing\ntours. Africans are presented as stereotypical children of nature and the highly sentimental\ntext carries the general message that Europeans destroyed African religion and 'freedom'\nbecause they could not understand customs which seemed to them cruel and crude.\nUrbanization, the accumulation of possessions, most aspects of modern technology, economic\nexploitation, criminality, prostitution, orphanages, and so on, are described as European\nimportations to Africa, so that the original state of innocence has disappeared (p. 201) and\n'. . beautiful beads were exchanged for miserable rags which were always torn, dirty and full\nof vermin' (p. 18). There are no photographs to illustrate this dreadful series of events; yet\nperhaps all is not lost, for we are told 'When travellers tell of the infinite poverty of the\npopulation, it is only partly true, for the judgement is a European one and what we consider\npoverty is often no more than a form of contentment we do not know' (p. 13). We learn\nnothing here about African societies, either from the text or from the carefully selected\nphotographs: we learn only what Gert Chesi thinks of them. Nevertheless this book is worth\nmore than a casual glance for the photographs alone.\n\nIf this is the book you remember, [you can use WorldCat to find where any of the several editions are located in a library near you](_URL_0_)."
]
}
|
[] |
[
"http://www.amazon.com/The-Last-Africans-G-Chesi/dp/0847802515"
] |
[
[
"http://www.worldcat.org/title/last-africans/oclc/5389163/editions?referer=di&editionsView=true"
]
] |
|
i0zky
|
Can gravity waves split a black hole?
|
In a binary black hole system, energy from the orbit is dissipated through gravity waves, which causes the orbit distance to decrease. (right?) I'm guessing that this phenomenon is time-reversible, meaning that if both the gravity waves and the black holes were to reverse direction, their orbit would increase.
When black holes merge, they release a massive amount of energy as gravity waves. After the event, if these waves were to reverse, would the black hole be split into a binary system?
|
askscience
|
http://www.reddit.com/r/askscience/comments/i0zky/can_gravity_waves_split_a_black_hole/
|
{
"a_id": [
"c1zzwdg",
"c200scs"
],
"score": [
2,
3
],
"text": [
"Yes the Einstein equations are time-reversal invariant, so if you were to simulate this numerically, you could simply run the \"movie\" backwards and get your desired result of splitting a black hole with gravity waves. However, non-GR effects will mess this up - most notably the fact that black holes have maximal entropy. \n\nSo essentially running the system backwards won't split a black hole apart without some additional inputs that allows entropy to increase on the whole, which it will not if you simply split up a black hole into two in a process that conserves mass/energy.\n\nSo the answer is likely no in reality.",
"Unfortunately it's impossible for black holes to split, as a direct result of Hawking's area theorem (i.e., the second law of black hole mechanics). The area of a black hole has to be a non-decreasing function of time, so a process which leaves the total black hole area less than it was before can't occur. Black hole bifurcation is such a process. It's impossible to contrive a scenario in which the two new black holes have a greater combined area than the first one. This also puts a limit on how much energy can be radiated away in gravitational waves when black holes merge, for example.\n\n*(If this sounds a lot like the second law of thermodynamics, that the total entropy of a system can't decrease, you're right: as it turns out, a black hole's entropy is directly proportional to its area. This is why this law has the suggestive name of the \"second law\" of black hole mechanics. Each of the laws of black hole mechanics has a direct analogue in thermodynamics. Fascinatingly, it's not until you throw quantum field theory in the picture that this turns from an analogy to a correspondence.)*\n\nThis result is purely classical (i.e., it involves nothing but GR and some assumptions on the matter and geometry you're dealing with) so it should satisfy time-reversibility. Usually when a statement about black holes looks time-irreversible, the solution is that the reversed statement applies to *white holes*, and I'd imagine that's true here (although astrophysical white holes are unlikely to exist due to stability issues and whatnot, so we tend to ignore them!). This is the solution, for example, to the seeming time-irreversibility of the fact that objects can go inside, but never outside, the event horizon."
]
}
|
[] |
[] |
[
[],
[]
] |
|
8oshns
|
why do you have to fast before getting certain blood tests?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8oshns/eli5_why_do_you_have_to_fast_before_getting/
|
{
"a_id": [
"e05qfrr",
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"e05xlww",
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"e061iry",
"e0693jc",
"e06kwvd"
],
"score": [
5,
109,
39,
2,
4,
2,
2
],
"text": [
"The Fasting Blood Glucose Test is the primary test for diabetes. It's the routine bloodwork test that is most likely the cause of your instructions to fast. There are others, but usually that's a function of something specific the doctor is investigating.",
"it depends on the blood tests, however, its typically to get rid of all the fats and sugars that are suspended in your blood following a meal.\n\nIf you fast, then your body will process those fats and sugars from your blood. Whats left over are the risiduals which are produced by your body (ie, chloresteral, insulin etc...). By fasting they can get a somewhat accurate snapshot of the levels in your blood to know if you have high chloresteral due to your liver producing too much or insulin levels due to diabetes etc...",
"To make sure it’s JUST your blood and your body, not your food.\n\n\n\nFor example, I am not diabetic, if I eat something sugary, my blood sugar will spike THEN my insulin will bring it down.\n\n\n\nIf u/viccsilver, who is diabetic, eats something sugary, their blood sugar will spike and will not be brought down.\n\n\n\n\n\nIf we had both just eaten, the spike wouldn’t tell the doctors anything. They need to see how the body reacts.",
"Blood tests are a snapshot in time. If you slam three donuts and get blood-work done thats not a real accurate picture of whats going on in your body all the time. ",
"Meals disrupt things in variable ways (depending on how long ago you ate and how much it was). It's like if you were trying to measure how deep a pool is at a water park - you'd want to make sure the waves were turned off and the water was still before taking your measurement. ",
"All I know is I'm tired of having to go through the same process my mother tends to go through getting a fasting blood draw. Namely getting stuck multiple times because of rolling veins, and having to regularly use a 'butterfly' needle to draw the blood. I am diabetic, never on insulin but I have always taken pills to control my blood sugars. For some strange reason I also have issues with only being able to sleep six hours at most, and that is pushing it.",
"I once was going to get tested for my blood sugar. Didn't even think of it and had an iced cappuccino on my way. \n\nGet a call from my doctor in distress about my blood sugar levels... explained myself and had to go again but this time I wasn't allowed any of those.\n\nThat is why you need to fast for certain blood work testing."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[]
] |
||
3sovi6
|
Did the US and the Allies seriously consider joining the Germans to set a counter offensive on the USSR closer towards the end of the War in 45? If so why didn't they take that route?
|
I recognize the fact that the US had nukes and felt that would save them some time but why didn't they just want to finish the job early rather than over the next several decades with the Cold War?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3sovi6/did_the_us_and_the_allies_seriously_consider/
|
{
"a_id": [
"cwz9u1m",
"cwzc79n",
"cwzna1t"
],
"score": [
2,
22,
3
],
"text": [
"Thought/relevant question.\n\nCan someone tell me the size of the Allied air forces compared to the Soviet ones in 1945?\n\nI assume that the Soviets could have held air supremacy over at least the Soviet Union against the Allies. Nuclear bombs at the time were delivered by bombers. The US would have to get bombers past what was perhaps the most powerful air force in the world at the time.\n\nCould nukes have been realistically brought to bear against the Soviet Union at that time?",
"An annihilatory attack on the USSR was a seriously discussed in many parts of American society at the time. Some of the proponents were surprising - Bertrand Russell \\[1] for instance. There was also a major movement to put atomic weapons under control of the United Nations e.g \\[2]. I can't find any overall discussion of contemporary thought in the UK (which would have had a veto at this time), but it appears that Churchill thought such a war necessary \\[3].\n \nA practical problem was that it turned out that the USA *did not have any bombs*. This was discovered by Lilienthal, first head of the AEC, when he visited Los Alamos in 1947 \\[4]. \"Actually, we had one [bomb] that was probably operable when I first went off to Los Alamos: one that had a good chance of being operable\". Apparently most of the the technicians had left after the war, many diagrams and plans had been lost (including all details of the gun-type uranium bomb), and the plutonium bomb had never been \"weaponised\" to make it possible to assemble it quickly, store it for more than a few days, and transport it without a serious risk of unwanted explosion.\n\nReferences below are taken from \"Command and Control\" by Eric Schlosser. This is a popularised account and when I checked some of his references, they didn't match what he put in the text - hence I've noted what I've checked myself and removed some references that didn't tally.\n\n\n\n\\[1] \"Russell Urges West to Fight Russia Now\", New York Times, Nov 21, 1948 (I have only read the abstract due to the paywall). \n\\[2] \"[The Atomic Bomb and the Prevention of War](_URL_0_)\", Bulletin of the Atomic Scientists, Oct 1, 1946 (checked)\n\\[3] Trachtenberg, \"History and Strategy\" (not read) \n\\[4] Herken, \"Winning Weapon\" (checked)",
"There was no thought of the United States allying with Nazi Germany against Russia. \n\nWhen Germany's defeat was imminent (before the A bomb) Churchill apparently ordered a study of whether a British -US alliance could defeat the Soviet Union called 'operation unthinkable'. The study concluded that it would be a long war and against the odds, and generally a bad idea.\n\n_URL_0_\n\nThe Soviets had a huge advantage on the ground with more armored divisions, more artillery, more everything. Their soldiers and leaders were experienced, competent, and willing to endure horrible losses and conditions. Their equipment was also mostly good by 1945. The Soviets had a tactical airforce instead of a strategic force, but they had more fighters in the west than the western allies.\n\nWithout going too far into 'what if' territory, maybe a small number of A bombs makes a difference, maybe someone resorts to newly discovered nerve gas... I think under any scenario, this would have been a worse outcome than the subsequent Cold War struggle."
]
}
|
[] |
[] |
[
[],
[
"https://books.google.ca/books?id=WwwAAAAAMBAJ&lpg=PA1&pg=PA19#v=onepage&q&f=false"
],
[
"http://www.dailymail.co.uk/debate/article-1209041/Operation-unthinkable-How-Churchill-wanted-recruit-defeated-Nazi-troops-drive-Russia-Eastern-Europe.html"
]
] |
|
33pw54
|
why can we not consciously feel organs working in our body if they are continuously at work?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/33pw54/eli5why_can_we_not_consciously_feel_organs/
|
{
"a_id": [
"cqn8vvh",
"cqn8vw2"
],
"score": [
4,
2
],
"text": [
"Very few nerves in your internal organs, except for when they need to tell you that something hurts. Theres also very little movement, so you wouldnt feel it that way. But you do feel your stomach rumble or growl right? That would be one example.",
"Because they aren't innervated in the same way that, for example, your skin is. There are many types of innervation - for example, if you get bloated, you can feel that, but it's not the same type of feeling as if you scratch your skin. If you have gallstones, and the bile duct gets blocked/irritated, it can be a very immediate, different type of pain. If you have to urinate very badly, obviously that feels quite different as well.\n\nThere is no real reason for us to be able to feel our organs working, so we don't have that innervation."
]
}
|
[] |
[] |
[
[],
[]
] |
||
3wsnqc
|
why is there alot more hype and excitement for star wars episode vii than there was for episode i?
|
I remember when Episode I came out and there didn't seem to be even half the hype there is for Episode VII. Is the marketing different? Online environment and connectivity?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3wsnqc/eli5_why_is_there_alot_more_hype_and_excitement/
|
{
"a_id": [
"cxyqemt",
"cxyqnl8",
"cxyqsha",
"cxyqvmf",
"cxz7g3l"
],
"score": [
22,
4,
10,
3,
2
],
"text": [
"I think you are vastly mis-remembering the hype. Go look up some videos of lines for Phantom Menace. The toy thing was the same too, I remember getting Lego sets before the movie even came out.",
"I don't think you're remembering the hype as it was. Disney owning Lucas films and their marking style isn't any different from when Lucas owned it. I remember, especially for episode 2 but for all the prequels that if it was sold in a store it the star wars label was slapped on it. Nothing really had changed imo.",
"There was a ton of hype surrounding Episode I... but the big difference is that there was no social media, no podcasts back then! So a lot of the discussions about were what the mainstream media wanted to cover and there weren't the outlets like Facebook, Twitter, Reddit, podcasts, etc. to discuss it, there was no online release of previews to get people hyped up, etc.",
"There was a lot of hype for Episode I, but... it didn't have the Disney Machine behind it. Disney is squeezing every last penny out of this thing right now. There were always advertisements and cross-promotions, but not to this degree. \n\nThere's also a much greater sense of hope for redemption, after the last trilogy...",
"Episode I hype was an order of magnitude greater than this.\n\n > Employment consultant firm Challenger, Gray & Christmas estimated that 2.2 million full-time employees missed work to attend the film, resulting in a US$293 million loss of productivity. According to The Wall Street Journal, many workers announced plans to view the premiere that many companies closed on the opening day. Queue areas formed outside cinema theaters over a month before ticket sales began.\n\n_URL_0_"
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Star_Wars_Episode_I:_The_Phantom_Menace#Release"
]
] |
|
9868bj
|
why do americans have 5k races when we use miles?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9868bj/eli5_why_do_americans_have_5k_races_when_we_use/
|
{
"a_id": [
"e4dlc5p",
"e4dn5on"
],
"score": [
49,
4
],
"text": [
"Running is an international sport, and the standard distances are in meters or kilometers.\n\nOther sports, like tennis, traditionally have Imperial measurements, and those are used even in countries that use the metric system.",
"Americans mostly use imperial measurements but do use metric as well.\n\nMetric is taught in schools alongside Imperial and most Americans have at least a basic understanding of it."
]
}
|
[] |
[] |
[
[],
[]
] |
||
2vqih9
|
why do restaurants' food taste so much better when the ingredients are relatively inexpensive?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2vqih9/eli5_why_do_restaurants_food_taste_so_much_better/
|
{
"a_id": [
"cok12yb",
"cok17ub",
"cok188n"
],
"score": [
15,
2,
7
],
"text": [
"More butter, more salt, better equipment. There isn't much more to say, restaurant food is intense, also lots of prepared ingredients that home cooks don't take the time to do (like sauces) ",
"Fat, sugar, salt, and MSG. Those are things that your body craves, and so eating anything loaded with those things, even something gross, tastes awesome.\n\nYour body will make something that has stuff it craves taste good. People who are starving or lacking a specific nutrient will often crave, and enjoy the taste of, things that are really gross. This is noted a lot in people stranded at sea who develop a love of fish eyes and livers. This is also way many cultures have foods that are really gross but still popular.",
"Proper seasoning (salt) when cooking.\n\nYour food should be salted when cooking *not at the table*. Unfortunately most home cooks just don't know how to do this correctly."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
31g4id
|
is there a reason why people like to "get sun"?
|
Beyond getting a tan
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/31g4id/eli5_is_there_a_reason_why_people_like_to_get_sun/
|
{
"a_id": [
"cq17s01",
"cq19yey"
],
"score": [
2,
2
],
"text": [
"Your body requires sunlight to synthesize vitamin D IIRC.",
"There are several studies which links sun exposure to production of \"feel-good\" endorphins. Also, Vit D."
]
}
|
[] |
[] |
[
[],
[]
] |
|
12a6mg
|
Why does body odor often smell like onions?
|
askscience
|
http://www.reddit.com/r/askscience/comments/12a6mg/why_does_body_odor_often_smell_like_onions/
|
{
"a_id": [
"c6tfid6"
],
"score": [
2
],
"text": [
"The smell of onions is caused by the breakdown of certain amino acids. The smell of sweat is also partly caused by this process as well. Both sweat and onion end up with similar amino acid derivatives when they undergo this process and you have similar smells caused by similar molecular structures of these compounds. \n\n_URL_0_\n\n"
]
}
|
[] |
[] |
[
[
"http://en.m.wikipedia.org/wiki/Body_odor#section_1"
]
] |
||
418hsp
|
Are all wavelengths of EM radiation, for which an optical lens is transparent, refracted by it?
|
askscience
|
https://www.reddit.com/r/askscience/comments/418hsp/are_all_wavelengths_of_em_radiation_for_which_an/
|
{
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"cz0gab0"
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"score": [
7
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"text": [
"Yes. Anytime there is a differnce in refractive index, there is refraction. There is no solid or liquid material that has the same index of refraction as air. Therefore, anytime light travels from air into a transparent liquid or solid, it refracts, no matter the wavelength of the light. For certain materials and certain wavelengths, the index of refraction may be very close to the index of refraction of air and therefore the refraction may be small, but it is still there.\n\nYou have to also realize that refraction is a simple wave effect that depends on the material being approximated homogenous on the scale of the wavelength of the wave. For high frequency electromagnetic radiation, such as gamma rays and x-rays, the particle nature of the radiation becomes more significant and the non-homogeneous atomic structure of materials becomes more significant. As a result, refraction alone is a poor description of what high-frequency electromagnetic waves experience when they pass through a material. More significant are effects such as crystal diffraction and atomic absorption."
]
}
|
[] |
[] |
[
[]
] |
||
aj7o3h
|
mold spores affect on the human respiratory system.
|
ELI5: how do mold spores affect the human respiratory system, and how do the different types of mold affect it differently
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/aj7o3h/eli5_mold_spores_affect_on_the_human_respiratory/
|
{
"a_id": [
"eetm9ua"
],
"score": [
4
],
"text": [
"Mold likes to grow in cool, wet areas. The danger of mold spores depends on their ability to tolerate the heat inside your body as well as their ability to avoid detection by your immune system.\n\nThere are fungal spores everywhere and it would be an unusual breath in which we inhaled none of them. These are generally opportunistic infections that take advantage of people with compromised immune systems. In a healthy person, your white blood cells simply migrate out of the blood across the thin membranes of the lungs and eat the fungus to death. "
]
}
|
[] |
[] |
[
[]
] |
|
4dfwie
|
What happened to the Irish Druids?
|
So, as I understand this, the Romans did a fairly solid job of destroying most of the Gaelic Druids, destroying their groves and killing the druids when they could capture them. A lot of damage was done to some major places of gathering in Whales as well, if I remember correct. My question though is, what happened to the druids in Ireland?
Rome never really did much there in terms of conquest, so they sure were not out there killing druids like in other places of conquest, so what happened? Was it simply an older faith that was lost when Christianity started to spread there? The lack of written language and tradition, the tribal concept of the island, was it all simply washed up when missionaries arrived and started to convert the people?
Thank you for the help in my better understanding of this.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4dfwie/what_happened_to_the_irish_druids/
|
{
"a_id": [
"d1qmi91"
],
"score": [
21
],
"text": [
"/u/depanneur and I double-teamed a similar question a little while ago. Since it was both of us, [I'll point you to the thread](_URL_0_) rather than copying the answer here. :)"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/3tbeev/when_would_the_last_druids_have_died/"
]
] |
|
5u7d3a
|
why is it preferable to ask for someone's resignation rather than just fire them with cause?
|
Recent National Security Advisor resignation got me thinking about this.
Also the US president's penchant for firing people before he took office would lead me to assume he would rather fire people
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5u7d3a/eli5_why_is_it_preferable_to_ask_for_someones/
|
{
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68,
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"text": [
"My police friends tell me it's common to ask for resignation rather than get fired because you \"choose\" to leave and look for employment elsewhere whereas being fired is a career ender. I'm sure a lot of this applies elsewhere, even in politics. Beyond that, I dunno.",
"Resignation just looks better than being fired. I'm sure the ones resigning are being told \"Resign, or you're fired.\"\n\nGiving them the option to save face.",
"It's less of a hassle, less paperwork, and less conflict. A person who *signs* a resignation letter even under pressure is less likely to stir up a shitstorm afterwards, because the administration / company could always say that *they* resigned and deny any pressure if necessary (arguably not in the Flint case, but in general).\n\nIt's also supposed to be a good practice because it allows both sides to keep face. The resignee does not get the stigma of being fired, and the employer does not get to field questions on why that person was fired. ",
"For the person who resigns it is them leaving on their own terms, technically, which helps them on their next job search. Nobody wants a with cause termination on their employment record.\n\nFor the employer it saves them a lot of legal headache. When you fire someone you generally have to go through a lot of legal hurdles to ensure that everything is by the book in case the employee sues for their job back. But, if they resign you have much less fear of a legal battle and you can have them leave immediately rather than checking all the boxes from your legal/HR department to protect the company from an unlawful termination lawsuit.\n\nI work for a large company, when we fire people we generally have to put them on a performance improvement plan, then document the hell out of everything, then have counseling sessions, training sessions, etc etc etc. All because we're afraid of getting sued. It usually takes us 2-4 months of headaches, training and documentation to terminate someone \"the right way.\" This is also why if the person was simply a bad hire you'll often hear companies giving a compensation package. This is done so the employee is enticed to resign rather than try to stick it out during the process to terminate them. They'll get a lump sum of 3-6 months pay (usually) and can say they weren't terminated on their next job opportunity, they can simply claim to be the victim of \"downsizing\" or whatever it is they want to claim.",
"IF they resign they don't get to fill out a unemployment claim which is beneficial to the company.",
"A lot of answers here are correct. But there is another angle to this. \n\nAt Wendy's it was far better for an employee to quit then to fire them. Because if they got fired they had access to unemployment benefits. Especially if the reasons for termination were not properly documented (they typically had to have 3 write ups on the same offense unless it was something like stealing). If the employee quit however they would not have access to unemployment benefits. Whenever an employee successfully got unemployment it would cost Wendy's $ through raised premiums. "
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
|
ft63ds
|
Why wasn't ocean acidification a problem millions of years ago when the dinosaurs were experiencing extremely high levels of CO2?
|
My friend and I were talking about the effects of CO2 and he brought up a good point that CO2 has been really high in the past, but the ecosystems didn't collapse like we think they might from the recent spike in climate change.
He is pretty anti-climate change, and I usually lean toward the side of most scientists. I just wasn't able to give him a good answer for his argument.
My thinking was something like the rate of change in CO2 levels is much higher than it was millions of year ago and maybe the life forms had more time to adapt back then, but I'm not sure.
|
askscience
|
https://www.reddit.com/r/askscience/comments/ft63ds/why_wasnt_ocean_acidification_a_problem_millions/
|
{
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"text": [
"Another factor to consider is rate of change. When changes in the atmosphere, oceans, climate, etc. happen over geologic time, populations have the opportunity to migrate or adapt. When changes happen over human timescales, many populations are not able to adapt, and we get mass extinctions. \n\nThe current rate of change of atmospheric CO2 is unprecedented in at least the past 800k years (source: ice cores from law dome, dome c, vostok; direct measurement at mauna loa).\n\nAlso -- the burning of coal has been implicated as a partial cause of the great dying -- biggest mass extinction. From what I've read, major volcanic eruptions may have triggered the burning of massive coal beds. One line of evidence is fly ash in sediment layers of the appropriate age.",
"Another note -- before the great oxygenation event of the precambrian, carbon dioxide levels were much much higher than they are now. It wasn't a problem for life then because they were adapted to a reducing atmosphere. It also kept the planet warm enough to be habitable, as the sun was dimmer then (the sun brightens gradually over its lifespan; effect is too small to have any effect at the thousand-year scale but is super important at the billion year scale and will result in the planet being inhabitable in a billion or so years)",
"High atmospheric concentrations of CO2 that rise rapidly (like they are now) have most definitely been a problem for oceanic organisms in the geologic past. Specifically, ocean acidification caused by this phenomena is considered a contributing cause in the Permian-Triassic, the largest extinction event in Earth history, (e.g. [Clarkson et al, 2015](_URL_0_)), Triassic-Jurassic (e.g. [Greene et al, 2012](_URL_3_)), and the Cretaceous-Tertiary extinctions (e.g. [Alegret et al, 2012](_URL_2_)). More generally, it's been argued that ocean acidification is one of the most potent mechanisms for causing mass extinctions in the oceans (e.g. [Veron, 2008](_URL_1_)). Another contributor with more of a background in ocean chemistry, like say, /u/Chlorophilia, might be able to provide more details.",
"Records of past climate change are very useful for understanding how the climate system works (and interactions with the biosphere). However, caution is needed when using past climates as analogues for today and this question highlights why. To cut a long story short, ocean chemistry was very different during the Mesozoic which meant that prolific carbonate production was possible despite the high CO2 concentrations. \n\nIt is completely possible to have productive carbonate systems in a high-CO2 world. Carbonate systems were productive throughout much of the Mesozoic where CO2 concentrations were significantly higher than today, e.g. [Pomar & Hallock \\(2008\\)](_URL_4_) as a good review. \n\nThe vulnerability of marine calcifiers to dissolution (i.e. the primary reason why we're concerned about ocean acidification) is often thought about in the context of pH, or the acidity of the ocean, which is directly related to the atmospheric CO2 concentration. However, in reality, the critical parameter is *not* pH but rather than carbonate *saturation state*, which is effectively a measure of how stable carbonate (specifically calcite and aragonite in the case of most marine calcifiers) is in seawater. If the saturation state is below 1, carbonate is unstable and will dissolve. Conversely, if the saturation state is above 1, carbonate is physically stable - but most marine calcifiers require a carbonate saturation state that is [substantially higher](_URL_1_).\n\nThe carbonate saturation state is approximately proportional to the product [Ca^(2+)][CO3^(2-)], i.e. the concentrations of calcium and carbonate ions in seawater. [CO3^(2-)] is [strongly dependent on pH](_URL_3_) - as the ocean pH drops, the concentration of carbonate ions also drops and therefore so does the carbonate saturation state. This is the mechanism by which ocean acidification damages carbonate systems. \n\nDuring the Mesozoic, due to the higher atmospheric CO2 concentration and the resulting lower ocean pH, [CO2^(2-)] was also lower. *However*, [Ca^(2+)] was significantly higher. The reasons for this are complex and not fully understood but is generally thought to be due to changes in rates of oceanic crust production, e.g. [Hardie \\(1996\\)](_URL_2_). However, the fact that [Ca^(2+)] was higher is well constrained and the result is that, despite the lower ocean pH, the background carbonate saturation state during the Mesozoic was actually similar to today, e.g. [Tyrell and Zeebe \\(2004\\)](_URL_0_). So higher CO2 was not an impediment to carbonate production during the Mesozoic, and in fact may have even contributed to their productivity, e.g. [Iglesias-Rodriguez et al. \\(2008\\)](_URL_5_).\n\nSo there is no contradiction to productive carbonate systems during times of high CO2 per se, *as long as the carbonate saturation state remains high*. The issue is when you rapidly change change one of the levers of the carbonate saturation state (which in practice means ocean acidification, because [Ca^(2+)] generally only changes over millions of years). As /u/CrustalTrudger explained, there are many cases in the past where rapid injections of CO2 (where the sudden drop in [CO3^(2-)] overwhelms the higher background [Ca^(2+)]) results in a significant drop in the carbonate saturation state and hence catastrophic consequences for marine calcifiers. A similar thing is occurring today, except even more rapidly than any geological analogue we are aware of."
]
}
|
[] |
[] |
[
[],
[],
[
"https://science.sciencemag.org/content/348/6231/229.full",
"https://link.springer.com/article/10.1007/s00338-008-0381-8",
"https://www.pnas.org/content/109/3/728.short",
"https://www.sciencedirect.com/science/article/abs/pii/S0012825212000463#s0120"
],
[
"https://www.sciencedirect.com/science/article/pii/S0016703704001681",
"https://www.annualreviews.org/doi/pdf/10.1146/annurev.marine.010908.163834",
"https://pubs.geoscienceworld.org/geology/article-lookup/24/3/279",
"https://www.nature.com/scitable/content/ne0000/ne0000/ne0000/ne0000/25853439/2-626w_1_2.jpg",
"https://www.sciencedirect.com/science/article/pii/S0012825207001857",
"https://science.sciencemag.org/content/320/5874/336"
]
] |
|
6qexw5
|
why are advertisers suddenly demonetizing so many popular youtube creators' content?
|
It seems like this just happened in the last several months. Many popular you tubers are no longer getting ad revenue. Why wasn't this a problem for the advertisers in the last several years, and why is it suddenly a problem now?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6qexw5/eli5why_are_advertisers_suddenly_demonetizing_so/
|
{
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"dkwqt8m",
"dkwrs32"
],
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4,
7
],
"text": [
"My Hypothesis: Most likely because a lot of Youtubers will suddenly open up about their political views. \n\nThink of it like this, Joey is a youtuber. Company A endorses Joey but at the same time Company A says that they are not involved in politics. \n\nJoey suddenly releases a video stating how much he hates America and the world is flat.\n\nPeople look at company A and go \"Oh that company must agree with him\". Company A looks bad.\n\n\nLoose ends.",
"They were more or less ignoring the Youtubers political/racist/sexist/controversial views until it became a national story and they were 'forced' to pay more attention and demand Google stop putting their ads on (insert politically incorrect flavor of the month) videos.\n\nMore generally you can no longer speak to different audiences differently *once you get caught*. Microsoft got flack for white-washing a black actor for advertisements to Norway, which is 98% white. It wasn't 'hidden' very long. Now they just air different ads in different countries, but this costs more.\n\nSome companies like to advertise on off-color sites so long as it doesn't cause a problem with them with the population at large, but once it is they are always *SHOCKED gambling was happening in this establishment, we'll fix the problem right away.*. And a lot of companies were content to advertise 'everywhere' until a technological means was provided to easily blacklist certain kinds of content.\n\nAt it's heart this is a story of technology. Prior to a couple of years ago the kind of deep-learning AI that can watch a video and decide if it's racist or violent or adult or underage simply didn't exist, at least not without a lot of human intervention. The recent hub-ub about racist Youtubers forced Google's hand and they rolled out the AIs they had that understand racism better than most liberals. And cussing, and adult videos, and everything else a wholesome family-friendly multi-national mega-corp might not want to be associated with."
]
}
|
[] |
[] |
[
[],
[]
] |
|
hfz8b
|
How warm would the Earth be if it we were not in orbit around the Sun?
|
Recently [this link](_URL_0_) was [posted in /r/Astronomy](_URL_1_)
The first question that comes to mind is:
How warm would the Earth be if it we were not in orbit around the Sun?
And the second is
Thinking of the Super-Earths that have been found, how big would a planet would there have to be so that it would still retain enough heat (even after a long period of time) for water to remain liquid?
I imagine that it would cool off for a long period of time, and eventually everything would freeze solid, all the way to the core, but that larger planets would cool down at a slower rate compared to smaller planets.
(looking at the scifi scenario of a planet with life on it that was forever lost among the stars)
Would it all freeze solid within just a few thousand, or maybe millions of years regardless?
EDIT: and thanks for all of the knowledgeable answers and helpful pointers
|
askscience
|
http://www.reddit.com/r/askscience/comments/hfz8b/how_warm_would_the_earth_be_if_it_we_were_not_in/
|
{
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6
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"text": [
"I'm no astrophysicist, but I'm pretty sure that without an internal or very nearby heat source of great magnitude, it would get very cold very fast.",
"Disclaimer, I'm just going to work out how cold the Earth would eventually get here which is not what you asked. But I don't really know how to work out how long the Earth would take to cool down to this temperature.\n\nFirst find the power output of the Earth's core (which I believe produces a little heat due to the decay of radioisotopes) and assume at equilibrium (when enough time has passed that nothing changes any more) that amount of power is being radiated by the Earth's surface. You'd need the Stefan–Boltzmann law to do this, detailed here:\n\n_URL_1_\n\nSo the total power P is:\n\nP = (Surface Area of Earth) * sigma * T^4\n\nRearrange:\n\nT = forthRoot(P/(Surface Area of Earth * sigma))\n\nAnd that would be the equilibrium temperature of the Earth.\n\nOkay, a little random googling and I found this:\n\n_URL_0_\n\nSuggests the total power output of the Earth's core is 44 Terawatts. It's from an internet forum so treat that figure with a pinch of salt.\n\n[So here's your answer for the temperature](_URL_2_). Still a little warmer than the cosmic microwave background."
]
}
|
[] |
[
"http://www.scientificamerican.com/article.cfm?id=free-floating-planets-microlensing",
"http://www.reddit.com/r/Astronomy/comments/hfoz2/free_worlds_billions_of_extrastellar_planetary/"
] |
[
[],
[
"http://www.physicsforums.com/showthread.php?t=394846",
"http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law",
"http://www.wolframalpha.com/input/?i=Sqrt%5BSqrt%5B44+TeraWatts+%2F%28%28Stefan%E2%80%93Boltzmann+constant%29+*+surface+area+of+the+earth%29%5D%5D"
]
] |
|
1m547z
|
if december 21st is called the winter solstice, then is it called the summer solstice in australia?
|
Because in Australia it is summer...
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1m547z/eli5_if_december_21st_is_called_the_winter/
|
{
"a_id": [
"cc5uubr"
],
"score": [
3
],
"text": [
"Yes. June 21 is our Winter Solstice."
]
}
|
[] |
[] |
[
[]
] |
|
22bgx3
|
what does it mean to be a psychopath? how can i spot one, and are they always dangerous?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/22bgx3/eli5_what_does_it_mean_to_be_a_psychopath_how_can/
|
{
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5,
4,
3
],
"text": [
"Psychopath is a very broad and misused term nowadays, however as I'm not a specialist I won't try and pretend I know more than I do. But yeah people use that term for a bunch of things now.",
"Psychopaths and sociopaths don't \"emote\" normally. They don't show fear in situations that would typically necessitate sweating or worrying. That's not to say that someone who is not scared easily is a psycho. People in the military or in dangerous careers have to have nerves of steel and function while in dangerous situations. People who are psychopaths and sociopaths have a slew of other behavioral issues as well in conjunction with their response to pain and pleasure, from not sleeping normally to deriving joy out of hurting others. They basically don't process emotions correctly or in a healthy way and they don't recognize other people as being significant. ",
"Here is a humorous TED talk from an author who spent some time studying psychopathy. \n\n_URL_0_"
]
}
|
[] |
[] |
[
[],
[],
[
"https://www.youtube.com/watch?v=xYemnKEKx0c"
]
] |
||
qfkbn
|
How come stuff sticks to other stuff when wet, and stays after it dries?
|
For example when you run through a sports field in the rain and blades of grass stick to your shoes, then later after everything is completely dry, the blades of grass stay stuck on your shoes. Or when you go to the beach and get wet sand stuck on your legs, then after it all dries, you have dry sand stuck on your legs, when usually dry sand would just fall off.
|
askscience
|
http://www.reddit.com/r/askscience/comments/qfkbn/how_come_stuff_sticks_to_other_stuff_when_wet_and/
|
{
"a_id": [
"c3xbepm"
],
"score": [
5
],
"text": [
"Part of this is explained by the high surface tension of water. It wants to minimize the amount of surface area exposed to air. You put a drop of water on a surface that is non-polar (low surface energy) like wax and the drop minimizes its surface area by taking a spherical shape. The water on a blade of grass has less surface area (exposed to air) when it is in the shoe-water-grass sandwich. In order to remove the grass from the shoe you must create new surface area and pay an energy penalty in doing so. Since the grass has low mass, gravity doesn't provide enough force to overcome this energy barrier. So that gets the grass there in the first place, but what keeps it there after the water is gone? Adhesion is primarily a result of weak intermolecular Van der Waals forces. There usually aren't chemical bonds between things that are \"stuck\" together. All that is required is to get two things close together and they will stick. The blade of grass is fairly compliant and the water helps it conform to the surface of the shoe. When the water is gone, if the grass has enough of its surface close enough to the shoe the Van der Waals forces can exceed the force due to gravity and the blade sticks."
]
}
|
[] |
[] |
[
[]
] |
|
4z6e3j
|
how do bugs like flies survive a drop from terminal velocity
|
If a fly falls from 6ft and reaches terminal velocity, how does it survive? To them, the ratio of that height is very high. Humans can barely survive a drop from 2 floors depending on how you land.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4z6e3j/eli5_how_do_bugs_like_flies_survive_a_drop_from/
|
{
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5
],
"text": [
"In the same way as a human with a parachute survives falling from 10,000 feet at terminal velocity - their terminal velocity is much slower, so the landing is safer. If you scale an object up to double all its dimensions, its surface area is multiplied by four but its mass is multiplied by eight. This increases its terminal velocity because the force from gravity trying to speed it up (linked to mass) increases faster than the drag trying to slow it down (linked to surface area).",
"Small things tend to be less breakable than large things, because the tension and compression forces caused by bending them scale up out of proportion to their size. This was observed and explained by none other than Galileo in Day One of his \"Two New Sciences\":\n\n_URL_0_\n\n > Who does not know that a horse falling from a height of three or four cubits will break his bones, while a dog falling from the same height or a cat from a height of eight or ten cubits will suffer no injury? Equally harmless would be the fall of a grasshopper from a tower or the fall of an ant from the distance of the moon. Do not children fall with impunity from heights which would cost their elders a broken leg or perhaps a fractured skull? \n\nAlso -- and contrary to what /u/Darkchyylde said -- small things tend to reach terminal velocity very quickly, and that terminal velocity is slower. This is because the air drag force is proportional to the cross-sectional *area* of an object, while the gravity force is proportional to its mass and thus its *volume*. The area goes up like the length squared, but the volume goes like the length cubed, so at a given velocity, the gravity force is bigger than the drag force for big objects, and vice versa for small ones.\n\n(If you liked that math argument without any actual math, you should go ahead and read Galileo, that's his jam.)"
]
}
|
[] |
[] |
[
[],
[
"http://oll.libertyfund.org/titles/753#Galileo_0416_65"
]
] |
|
3538on
|
why does a simple app such as iheartradio need access to my photos and call information?
|
I figured I'd get the app in case I ever wanted to listen to proper radio on my phone but it says it needs access to so many different things. I'd understand needing wifi info, maybe even location info, but why does it need to access my photos and my call info? My photos have nothing to do with them.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3538on/eli5_why_does_a_simple_app_such_as_iheartradio/
|
{
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"text": [
"Lots of apps ask for access to call info because that allows them to stop playing media when you receive a call. I'm not sure about photos. Does the app have profiles that let you set a profile picture? That would allow the app to let you choose one from your camera roll or gallery app.",
"I'll assume you are talking about Android.\n\n\"Photos\" just means they get access to your external storage. They could be storing all kinds of things on there. I know that iHeartRadio lets you create your own stations; perhaps those use photos from your gallery for the icons?\n\n\"Device ID & call information\" is necessary for apps like these. This permission allows the app to know when someone is calling, or you are in a call. They need this to pause the stream, lower/mute the volume, etc during calls.",
"We have a detailed explanation of the Android permissions we need and why we need them on our help site which you can find here: _URL_0_. (Mods, hope linking to the answer is okay).",
"This come directly from the [iHeartRadio website](_URL_0_). (linked by /u/iHeartRadioHelp below)\n\niHeartRadio permissions on Android\nThe Google Play Store recently changed the way they display required permissions from applications. iHeartRadio is an app with many features which requires extra permissions, these permissions are listed below along with an explanation of what they do and why we need them.\n\n**Identity** - Uses one or more of: accounts on the device, profile data. \nReason for permission: \n\nWe need this permission to create an iHeartRadio account and integrate with Google+.\n\n**Location** - Uses the device's location. \nReason for permission: \n\nWe need this permission to check your current location for a list of local Radio Stations.\n\n**Photos/Media/Files** - Uses one or more of: files on the device such as images, videos, or audio, the device's external storage. \nReason for permission: \n\nWe need the permission to store album art on your Android phone to reduce network communication and to improve performance. This permission does not give us access to your photos or videos.\n\n**Wi-Fi connection information** - Allows the app to view information about Wi-Fi networking, such as whether Wi-Fi is enabled and names of connected Wi-Fi devices. \nReason for permission: \n\nWe need this permission to get the Wi-Fi status of your device to determine whether you have an active connection. \n\n**Device ID & call information** - Allows the app to determine the phone number and device IDs, whether a call is active, and the remote number connected by a call. \nReason for permission: \n\nWe need the permission to read phone status to know when you have received or end a phone call. This prevents our app from interrupting your call and allows us to resume playing when your call ends.\n\n**Edit:** If you suspect that there is privacy concerns about an app that you are using (Due to the permissions it needs or something else), you should check the App / developer's privacy policy. It should detail everything that they collect and how they use it. If the developer doesn't have a privacy policy, proceed with caution. But realize that not every app out there is not trying to sell your information.\n"
]
}
|
[] |
[] |
[
[],
[],
[
"iHeartRadio.com/AndroidPermissions"
],
[
"http://help.iheart.com/customer/portal/articles/1669053-iheartradio-permissions-on-android"
]
] |
|
2k2wak
|
Does passing electricity though water effectively sterilise it?
|
can you even kill bacteria with electricity?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2k2wak/does_passing_electricity_though_water_effectively/
|
{
"a_id": [
"clhvk21"
],
"score": [
3
],
"text": [
"Effectively, yes! So as you should know, one of the major disinfection processes involve chlorine and hypochlorite as disinfectants. Recently, people have been trying to steer away from these expensive processes. Another way to disinfect water is through electrolytic processes. Some of these processes are being utilized in Africa where safe water is a scarcity in many parts of the continent. One of the major ones that I know of involves solar cells as the means of electricity. Photovoltaic cells are able to take solar energy and transform it into electrical energy. In a nutshell, photons are absorbed by a semiconducting material which then excite electrons. The electron is then able to travel to the electrode and the electricity of captured. The electricity, now in the water, can create oxidative radicals to kill any microorganisms. "
]
}
|
[] |
[] |
[
[]
] |
|
chvwqx
|
What were Soviet computers like during the Cold War? Were they clones of Western architectures or completely different?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/chvwqx/what_were_soviet_computers_like_during_the_cold/
|
{
"a_id": [
"ev129og"
],
"score": [
5
],
"text": [
"Until someone gets to this, answers to similar questions can be found [here]( _URL_1_) and [here](_URL_0_)\n\nedit: the first link answered by u/joshtothemaxx"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/2legwa/in_soviet_russia_did_they_make_computers_copying/",
"https://www.reddit.com/r/AskHistorians/comments/56o4h9/how_powerful_were_soviet_computers_what/"
]
] |
||
57slgt
|
why are apples grown from seed bitter, and only sweet if grown from a graft?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/57slgt/eli5_why_are_apples_grown_from_seed_bitter_and/
|
{
"a_id": [
"d8ukuli",
"d8uq0oi"
],
"score": [
6,
3
],
"text": [
"Apple genetics is really complex. A good fruit has to have exactly the right mix of genes...anything else just results in bad taste. \n\nEvery time you grow a fruit from seed you are getting a totally new mix of genes, and that means you are pretty unlikely to hit on a winner. Apple breeders grow thousands and thousands of trees from seed to find the one that is good.\n\nBut if you grow from a graft, you aren't reshuffling the genetics at all. The apples will be the same as the tree you grafted from, so presumably pretty good (unless you graft from a bad tasting tree, but that would be dumb).",
"/u/atomfullerene gave a good answer, but it can be even worse than he said. There is a good chance that an apple seed is not a mix of genes from the same variety.\n\nIn the wild an apple only makes a small fruit to attract animals to scatter the seeds inside. (People have bred for larger, sweeter fruit.) The tree only \"wants\" to produce fruit after the flower is pollinated to produce seeds.\n\nBut the tree is producing masses of flowers at the same time. Odds are most of the flowers would be pollinating each other on the same tree. That would tend towards inbreeding. The tree doesn't \"want\" that. So it has mechanisms (don't know what they are) to inhibit flowers from accepting similar pollen.\n\nSo the flowers \"want\" to be pollinated by a different variety of apple. Farmers grow fields of the same variety of apple. If you go back in time, they all came from the same original tree. As far as the flower can tell, they are still on the same tree.\n\nTo get yields up, farmers have to use different apples as pollen donors. It can be any variety that produces lots of pollen at the same time as the desired apple is flowering. It doesn't matter if the donor has low quality fruit. I've read that they even use crabapples as a donor. Good luck getting good fruit from those seeds."
]
}
|
[] |
[] |
[
[],
[]
] |
||
2a532s
|
What would a super nova look like?
|
If you somehow had a spaceship that could survive the trip and you parked that ship next to a start that was just about to super nova, what would that look like? Does it immediately explode like a bomb, or would the process be slower?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2a532s/what_would_a_super_nova_look_like/
|
{
"a_id": [
"cirlmp5"
],
"score": [
3
],
"text": [
"If you were close to it, it would just be exceedingly bright. I've read that a supernova at the sun's distance would appear brighter than a hydrogen bomb detonating on your eyeball.\n\nIf you were a bit farther away, you'd see a bright flash and an expanding cloud of hot gas.\n\n_URL_0_"
]
}
|
[] |
[] |
[
[
"http://www.holoscience.com/wp/wp-content/uploads/2005/08/SN1987Atimelapse1.jpg"
]
] |
|
1mta4e
|
When castration (in regards to opera) fell out of vogue, was it universal? Were there some notable holdout states or organizations?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1mta4e/when_castration_in_regards_to_opera_fell_out_of/
|
{
"a_id": [
"cccfx8n",
"cccgg4n"
],
"score": [
22,
4
],
"text": [
"Oh hello there! A flair question! Whee! :)\n\nTheir death was more or less universal in opera, but there's a little that needs unpacking in your question. The first -- the creation of castrati was more or less exclusive to Italy from its heyday to death. No one else castrated little boys and trained them to sing. (I've read that there were some being made in Northern Germany but none of the \"big boys\" came from Germany.) So the entire production process of an operatic castrato -- meaning their birth, recruitment, castration, and extensive training which was probably the most important part -- was entirely an Italian process. The castrati, when they appeared elsewhere, were always an export product, along with the opera music they were trained to produce. \n\nYou can more or less identify 3 major waves/generations of big-name castrati, which I am pulling from [*The Great Singers* by Henry Pleasants.](_URL_6_) The generational nicknames and divisions are his. I’d probably myself maybe break these guys up into five generations actually, but this is a good overview. Sorry for the Wiki links but it’s mainly to save myself from writing out all their ding-dang long Italian names. \n\n1. The First Generation: [Siface (1653-1697)](_URL_9_), [Nicolini (1673-1732)](_URL_2_)\n\n2. The Golden Age: [Senesino (1686-1758)](_URL_8_), [Farinelli (1705-1782)](_URL_4_), [Carestini (1704-1760)](_URL_11_), [Caffarelli (1710-1783)](_URL_3_, [Guadagni (1728-1792)](_URL_7_)\n\n3. The Last Full Flower: [Pacchierotti (1740-1821)](_URL_5_), [Crescentini (1762-1846)](_URL_12_), [Marchesi (1754-1829)](_URL_10_), [Velluti (1780-1861)](_URL_0_ \n\nThe Catholic church first started using castrati officially in 1599, but possibly for longer before that. There’s also evidence of Byzantines using eunuchs in music, but castrati were in the very first operas in Italian courts in 1600, giving us a good official start date. \n\nTheir popularity grew alongside the growth of opera (which is a long story for another day), hitting their peak around the mid 18th century with Farinelli, Caffarelli, and Carestini up there in the “Golden Age.” If you check birthdays and do a little mental math, you can see a lot of the generation after them would have been castrated around the height of the castrati’s popularity, Velluti being quite a bit late though. \n\nSo what killed them off? Alas for all of us, nothing much to do with morality. Operatic tastes changed, the florid bel canto style became unfashionable, and that was the majority of the castrati’s charms. Having been extensively trained in florid singing since childhood, they were masters of the art, and when the art became unfashionable, their market advantage over women went away as well. Which you know about, but I’ll put [some more reading on that here](_URL_13_) for anyone reading over our shoulders. Add into that a Romantic-era taste for the “natural,” eunuchs being rather unnatural to some, and you’ve got a growing distaste for castrati. \n\nHowever, for your hold out, the Catholic church made a good hold out, and castrati continued to find a home in the Vatican up until 1913 when the last castrato on the roster retired. [More about that interesting man (and his oh-so-famous recordings) here.](_URL_1_) \n\nSo the time of the castrati, from church to opera to church, is about 1600-1900, but the reign of the King Castrati in opera was probably more like 1700-1800. But a century and some change is a pretty good run!\n\n(A note on French and German opera: While France had a very lively opera scene at the height of the castrati’s fame, the French HATED castrati and used high tenors in their place, so French opera never had a castrato tradition to die out. They had castrati in an extremely limited fashion in church (in the Chapelle Royale for one) but they just didn't tolerate them in opera. So French opera, while nearly as old as Italian, had no castrati tradition to die out. For German opera, Germans at that time mostly enjoyed opera in Italian, and the start of true German opera was a little too late to get castrati ingrained. So we’re most speaking Italian when we talk about the castrati!) ",
"How close is the counter tenor voice to a castrati?\n\nDid castrati take the same roles that counter tenors take today? In particular I am thinking about Handel's Julius Caesar."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Giovanni_Velluti_(castrato%29)",
"http://www.reddit.com/r/AskHistorians/comments/1jcijt/tuesday_trivia_and_were_rolling_primary_source/cbdak1e",
"http://en.wikipedia.org/wiki/Nicolo_Grimaldi",
"http://en.wikipedia.org/wiki/Caffarelli_(castrato%29)",
"http://en.wikipedia.org/wiki/Farinelli",
"http://en.wikipedia.org/wiki/Gaspare_Pacchierotti",
"http://www.worldcat.org/title/great-singers-from-the-dawn-of-opera-to-our-own-time/oclc/857557",
"http://en.wikipedia.org/wiki/Gaetano_Guadagni",
"http://en.wikipedia.org/wiki/Senesino",
"http://en.wikipedia.org/wiki/Giovanni_Francesco_Grossi",
"http://en.wikipedia.org/wiki/Luigi_Marchesi",
"http://en.wikipedia.org/wiki/Carestini",
"http://en.wikipedia.org/wiki/Crescentini",
"http://www.reddit.com/r/AskHistorians/comments/1m3qzr/tuesday_trivia_twists_and_turns_watershed_moments/cc5idox"
],
[]
] |
||
e0n754
|
I want to get a gift for a family friend that has a degree in Byzantine studies. Suggestions?
|
[deleted]
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/e0n754/i_want_to_get_a_gift_for_a_family_friend_that_has/
|
{
"a_id": [
"f8fn9it"
],
"score": [
3
],
"text": [
"Do you know what kind of Byzantine things he studies? I'm not sure what he would have already read or not, and there's lots of aspects of Byzantine history (military, literary, political, etc...I had a professor who was an expert on Byzantine gardens!)\n\nI would suggest Anthony Kaldellis, *Romanland: Ethnicity and Empire in Byzantium* (Harvard University Press, 2019), mostly because it's brand new and he might not have read it yet! But it also covers a lot of different topics, so depending on what his specialty is, he'll probably find something interesting in there."
]
}
|
[] |
[] |
[
[]
] |
|
43gcf6
|
When were actors and celebrities first called "stars"? Do we know who coined the phrase?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/43gcf6/when_were_actors_and_celebrities_first_called/
|
{
"a_id": [
"czi5glh"
],
"score": [
2
],
"text": [
"[Here](_URL_0_) is an example of the term being used to describe a theatre actor in The Gentleman's and London Magazine dated July 1765. I'm not certain this is the first time it was ever used. The phrase is used quite explicitly which, to me, suggests it wasn't a very common thing to say when this was written, meaning it's probably an early example. "
]
}
|
[] |
[] |
[
[
"https://books.google.co.uk/books?id=F_gRAAAAYAAJ&pg=PA424&dq=bright+star+appearing&hl=en&sa=X&redir_esc=y#v=onepage&q=bright%20star%20appearing&f=false"
]
] |
||
1khrps
|
why do some animals evolve for slow movement (snails, sloths, ect.)?
|
It seems like fast movement would be an adaptation most animals would have. Granted many faster animals are still nowhere near the fastest on the planet, but those faster animals are adapted to escape from predators.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1khrps/eli5_why_do_some_animals_evolve_for_slow_movement/
|
{
"a_id": [
"cbp1u2q",
"cbp1v90",
"cbp25f4"
],
"score": [
3,
4,
2
],
"text": [
"Well, there are costs to every 'upgrade' to an organism. When you buy a car, a bigger engine and better stereo cost you money. The same is true of animals - better defenses, faster movement, and things like that, tend to cost more \"money\". This \"money\" is usually the energy requirements of the animal.\n\nSo, you could imagine a super-fast slug, but it would require a ton more energy. And since slugs normally just crawl around eating leaves, your speedy slug would need to eat a lot more leaves to pay for that once in a lifetime dash from a predator.\n\nIt's all tradeoffs.",
"First of all, it's important to remember that evolution doesn't select for what's best, it selects for what *works*. \"Survival of the fittest\" is misleading, it really should be \"survival of the fit.\" Snails and other slow-moving animals seem to be doing perfectly fine the way they are, so there's no need to change.\n\nSecond, it's not necessarily always a good thing to be fast. Moving slowly takes a lot less energy. A sloth doesn't need to find as much food as, say, a monkey, because it's not burning up all those calories by swinging around in the trees and all that. Predators also don't notice them very well, because it's hard to pick out something that's just sitting still compared to a monkey that's running all over the place.",
"Everything in evolution is a trade off. Furthermore, while \"survival of the fittest\" makes people think about evolution as some sort of force always pushing animals towards some idealized perfect form, in reality it's much closer to \"survival of the barely fit enough\". As long as it's possible for a creature to survive in a niche, some form of life will eventually adapt to that niche. It's not like penguins sat down one day and thought \"the frigid wasteland of antarctica sounds like a great place to live\".\n\nSloths feed mostly on tree leaves. Leaves (like a lot of plant matter) have very little nutritional value, and take a long time to extract what is present. Grazing animals have adapted to eating grass by staying active and eating nearly continuously, and moving over large areas to gather enough food. That puts them out in the open the majority of the day, which makes them a prime target for predators. Sloths have gone the opposite direction, they react to the low nutritional value of tree leaves by having extremely slow metabolisms. That massively reduces the amount of calories they need to consume in a day, which allows them to survive on smaller diets. Furthermore they sit unmoving in trees for the majority of their life, which means they are harder for predators to reach or to notice, which is it's own survival strategy."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
rdlbb
|
How plausible is a laser gun?
|
I was talking to my friend that's really into physics and he said that if we concentrated enough photons we could make a laser for offensive use. Is he correct, and would we be able to concentrate light like that?
Do we have one, any other cool stuff about lasers etc?
|
askscience
|
http://www.reddit.com/r/askscience/comments/rdlbb/how_plausible_is_a_laser_gun/
|
{
"a_id": [
"c44y5kp",
"c44y61b",
"c44ycmu"
],
"score": [
3,
3,
11
],
"text": [
"So plausible that [it exists](_URL_0_)! We would just need to make those a little higher power to actually cut through metals and such like factories do.",
"Yes. High power lasers can do pretty impressive things. \n\nMachine shops already regularly use things like laser cuters to cut through inches of steel in seconds (certainly beats having to sit around carefully punching out pieces).\n\nThe hardest thing about using really high power lasers is how much energy they require, and how they need to be cooled. Handheld laser weapons are probably a long way off... Big fancy laser canons though... not as far off.\n\nOther cool things you can do with lasers: [LiDAR](_URL_0_)",
"It is important to distinguish between \"having a laser that can melt through metal\" and \"having a laser gun\".\n\nIn manufacturing, lasers are used to [weld](_URL_5_) or [cut](_URL_1_). These are certainly more powerful than your laser pointer, which is to say that they concentrate enough energy in a small space (and sometimes in a small amount of time, too!) to achieve destructive effects. *That doesn't make them weapons.*\n\nLasers suck up power, they have delicate optics, and the more powerful ones require quite a bit of cooling. These drawbacks are no big problem when the laser in question is in an air conditioned factory room, kept clean and dust-free, is regularly serviced and hooked up to a power line. They become a lot more problematic when you're talking about using a laser to replace an M-4 rifle.\n\nFor battlefield applications, the laser would have to be durable, serviceable, reliable even in unfavorable conditions such as rain, dust, sandstorms, extreme heat and cold. It would have to be somewhat portable, easy to use, and at least as effective (and cheaper) or a lot better than (at not too much of an extra cost) current guns.\n\nHaving said that, there are roles for lasers in the military. Low-powered lasers are used to [measure distances](_URL_0_) or to [guide weaponry](_URL_2_). There are also projects underway that use lasers as defensive weapons, to shoot down enemy missiles or other ordnance such as the (now-cancelled) [airborne laser project](_URL_3_) or the Army's [Centurion](_URL_4_). \n\nSo if you're going to see lasers being widely deployed in combat, they'll probably be used as point-defense systems to protect forward bases from mortar and rocket attacks, or mounted on ships. I doubt that we'll be seeing handheld laser guns replacing rifles though."
]
}
|
[] |
[] |
[
[
"http://www.youtube.com/watch?v=dhFuu3GpHDQ&feature=relmfu"
],
[
"http://en.wikipedia.org/wiki/LIDAR"
],
[
"http://en.wikipedia.org/wiki/Laser_rangefinder",
"http://en.wikipedia.org/wiki/Laser_cutter",
"http://en.wikipedia.org/wiki/Laser_guidance",
"http://en.wikipedia.org/wiki/Airborne_laser",
"http://www.army.mil/article/16279/White_Sands_testing_new_laser_weapon_system/",
"http://en.wikipedia.org/wiki/Laser_beam_welding"
]
] |
|
1t5als
|
how can journalist legally interview wanted criminals without having to disclose their location?
|
I'm just wondering because i just came across an interview where a Mexican journalist interviews one of Mexico's most wanted. How is this possible?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1t5als/how_can_journalist_legally_interview_wanted/
|
{
"a_id": [
"ce4h6d7",
"ce4lgy7"
],
"score": [
2,
2
],
"text": [
"They most likely come to an agreement or there is some law. Kind of like how a lawyer can know all of the crimes you've commited but by law cannot tell anyone.",
"Well, you're not legally required to report it if you meet wanted criminal. However, journalism is a very risky field, if you interview a criminal and don't report him then he goes out and commits another crime, you could be seen as allowing the crime to take place."
]
}
|
[] |
[] |
[
[],
[]
] |
|
47bmzg
|
With our new ability to measure changes in gravity, could information from within the event horizon of a black hole be communicated by creating gravitational waves within the black hole?
|
Let's say I have a gun, that when fired creates a (strong) gravitational field. Thus, firings of this gun could (I believe, correct me if I'm wrong) be measured with LIGO. Since a black hole's own gravity can escape it's event horizon (?), could firings of the gun be detected from within it? Could firings of different magnitude be used to transmit binary data?
Does this question make any sense at all?
|
askscience
|
https://www.reddit.com/r/askscience/comments/47bmzg/with_our_new_ability_to_measure_changes_in/
|
{
"a_id": [
"d0briu3",
"d0c01as"
],
"score": [
14,
3
],
"text": [
"Gravitational waves **cannot** escape a black hole.\n\nOn the subject of \"the gravity escaping the black hole\" [read here](_URL_0_)",
"I'd just like to point out that the LIGO experiment doesn't measure changes in gravity. We've been able to do that for a while (see [gravimetry](_URL_0_) and [gravity gradiometry](_URL_1_)).\n\nWhat the LIGO experiment can detect is gravity waves, which are not the same as gravity, and which manifest as distortions in space. Gravity is unchanged. An analogy with electromagnetism would be the electromagnetic field of a particle (say an electron) and the radiation emitted by the particle, which manifests as oscillations in the electromagnetic field."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/askscience/comments/45vidz/z/d00l0do"
],
[
"https://en.wikipedia.org/wiki/Gravimetry",
"https://en.wikipedia.org/wiki/Gravity_gradiometry"
]
] |
|
5dovdc
|
while eating, humming or anything to create a vibration in your head, why do digital clocks create a wave like pattern when looking at them?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5dovdc/eli5while_eating_humming_or_anything_to_create_a/
|
{
"a_id": [
"da66p5r"
],
"score": [
3
],
"text": [
"The digital displays don't update instantly. There's motion in the display. Just so fast you don't normally see it. But if you're moving your eyes in sync, it shows up. Electric toothbrush does this best."
]
}
|
[] |
[] |
[
[]
] |
||
2a0urw
|
If you are connected to a rope and the rope goes around the world and ends at you and you pull the rope, what happens?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2a0urw/if_you_are_connected_to_a_rope_and_the_rope_goes/
|
{
"a_id": [
"ciqgiz2"
],
"score": [
13
],
"text": [
"Okay, so let's throw some numbers at this: We want a good lightweight material like nylon that is stronger than steel.\nWe need to know the total weight of the rope, which is the volume multiplied by the density.\nThe density of Nylon 6,6 is 1.15g/cm^3\nIf we assume the rope is 25 cm^2 in cross section (i.e 5cm * 5cm)\nThe circumference of the earth is about 40,000km = 4000000000cm.\nSo the mass of the rope is 1.5 * 10^11 g = 1.5 * 10^8 kg = 150,000 metric tonnes.\n\nSo if you pull on it it would be the same as pulling on a rope attached to a building that is about half the weight of the empire state building.\n\nThe tensile strength of Nylon is about 45MPa, but the stress applied to the rope to displace one end by pulling the other (the weight divided by the cross-sectional area) is 588GPa.\nThis exceeds the tensile strength of the rope by a factor of 13,000.\nIn fact, the cross-sectional area would need to be about 30m^2 in order to not break under its own weight.\n\nIn summary, one of two things: Nothing, or the rope breaks.\n\nHowever, if you go into massless ideal ropes, then the problem is the exact same as what happens if you throw a rope over a tree branch and tie the other end to yourself and then pull- you go up.\n\n--\nEdit: Tidied up my math\n"
]
}
|
[] |
[] |
[
[]
] |
||
369qhi
|
Are there any known cases where a serial killer has targeted one of the main investigators in their case?
|
We've all seen it tons of times in TV and in movies, but does it happen in real life? Do serial killers ever try to kill (successfully or not) the detective/investigator/agent/whatever who is pursuing them? I don't just mean sending letters (through the media or otherwise). I mean how it's often portrayed in fictional stories (physically assaulting the investigator, kidnapping, murdering, etc).
Edit: I think targeting a close friend or family member of the investigator (specifically to hurt the investigator) counts, if there are any cases of that.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/369qhi/are_there_any_known_cases_where_a_serial_killer/
|
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"I've read hundreds of books on serial + mass murderers and this one is stumping me. I don't think there are any cases of a rather silly targeted \"I'm coming for you Detective Biff McBifferson\". Closest thing I can think of might be Eric Rudolph. He was hard core anti-gov't. He bombed an abortion clinic, but that wasn't the real target. He knew ATF and FBI would cordon off the area, and he had a second bomb set to go off later just outside this area, the goal being to kill the investigators themselves. It's a tactic that the IRA used to use. In that instance it didn't work because due to blind luck someone parked a big car in between the bomb and the investigators, and it deflected most of the blast. ",
"/u/abanks47 mentioned organized crime downthread. Though it might not fit the Hollywood \"Hannibal Lecter\" type of serial killer, many organized crime figures meet the traditional \"3 or more murders\" definition of serial killers.\n\nSo if you're prepared to accept organized crime figures as serial killers, a good place to start is the Sicilian Mafia. There was a notable spree of killings in the late 1970s and early 1980s of investigative and judicial figures.\n\nIt kicked off with the murder of Boris Giuliano, an Italian police officer who was killed after uncovering a major money-laundering operation by the Sicilian Mafia (the money was from heroin trafficking to America). The man convicted of killing Giuliano was Leoluca Bagarella, who [certainly meets](_URL_1_) the \"3 victims\" definition of a serial killer.\n\nUnfortunately, Giuliano's death was not the end of Mafia murders of people working in the criminal justice system. Two months after Giuliano was murdered, the crusading Anti-Mafia judge and former member of parliament Cesare Terranova was murdered along with his bodyguard, who was a police officer.\n\nIf you include 'conspiracy to commit murder' in the body count required to become a serial killer, then a good number of the Sicilian Mafia's leadership during the late 70s would qualify as answers to your question.\n\nThere was also a second major anti-government burst of violence from the Sicilian Mafia in the early 1990s, and the two most prominent victims were both judges: Giovanni Falcone and Paolo Borsellino. \n\nBoth Falcone and Borsellino had been prosecuting magistrates who went after Mafia figures. As the Italian justice system works differently than the common law adversarial system, these prosecuting magistrates occupy a legal role that combines investigative and adjudicative functions.\n\nThough I'm less familiar with it, the Colombian (and probably Mexican) organized crime groups can claim similar intimidation killings against people working in the legal system. The Medellin Cartel during Pablo Escobar's leadership made a frequent practice of killing police, journalists, judges, and even [members of government](_URL_0_).",
"I'm not entirely sure if this comment is allowed but wanted to pitch in and say maybe the folks over at /r/UnresolvedMysteries might know a bit about this. They're usually very nice and well-read in all sorts of criminal history, including serial killers. I apologise if I'm breaking a rule and if I am, I'll delete the comment and just PM the OP instead.",
"Closest I know of is Ridgway (\"The Green River Killer) going to lectures about the hunt for himself by author Ann Rule. Rule was a former cop turned true crime author and had good contacts in the police regarding the hunt, and Ridgway supposedly came to them to try to see how close they were to identifying him, and even asking questions.\n\nAs an aside, Rule previously shared a cubicle with Ted Bundy before his cross-country killing spree, when they both worked at a nonprofit.\n\nGreen River, Running Red by true-crime author and former police officer Ann Rule (September 27, 2005)",
"This was probably (almost certainly) more a case of accidental overreach, but the second-to-last victim of Charlie Starkweather and Caril Anne Fugate, the industrialist [C. Lauer Ward](_URL_1_), was a friend of the governor of Nebraska, and had actually been meeting with the governor when Starkweather and Fugate broke into his home and killed his wife and housekeeper. \n\nThen he came home, found them, and was killed himself. \n\nAfter Ward's body (and the bodies of his wife and maid) were found, Governor Anderson called the National Guard to help the Lincoln police, county sheriff and state troopers capture the killers. \n\nNow, Lauer wasn't targeted because he was investigating the killers, but he was definitely a prominent citizen, which was *probably* why he attracted the killers. I mean, I think they just went to the nicest house in the nicest part of town without knowing who lived there. \n\nOops, buddies with the governor. \n\n---\n\nI'm also certain that /u/meninthemirror/ is right about cartel violence, and that in certain places in Mexico, the local law enforcement was outright replaced by members of the cartel.\n\nAnecdotally, I heard about this firsthand while driving through Sinaloa in the 1990s. There's plenty on the record about the rise of the Zetas, though... most, however, within the 20-year exclusion rule. Much of the membership of the Zetas consisted/consists of [cops and soldiers hired by the Gulf cartel](_URL_0_). \n\nI'm not sure if \"mercenary\" counts as \"serial killer\" though. Not the same psychological profile. For one thing, they act under orders....\n\n\n\n",
"Alain Lamare. I have trouble getting sources in English, but he's kinda famous in France as \"le tueur de l'Oise\" / the Oise killer. A movie has been made about him last year, *La prochaine fois je viserai le coeur*. \n\nIt happened in 1978 and 1979. He's not really a serial-killer though. Or is he ? He tried though. He only killed once, but he tried numerous times. He boobytrapped stolen cars that blew up to cops face (not killing them), he attacked girls but only killed one, paralysing another, injuring a third, and the police tried to catch him for almost a year before they succeeded. During his crazy rampage, he sent letters to the police anonymously to say he did it, and said he would do it again. His letters raised suspicion because of how it was written: it was written as written by a cop. That helped catching him, event though the hierarchy first denied a cop could do it. He was indeed a cop ( a gendarme actually. A military, but with police duty. )\n\nSo Alain Lamare was investigating on his own case. So he knew what the cops plan was, and thought ahead.\n\nBut in the end he got caught. And, the thing is, regarding this post's topic, he planned to attack his fellow gendarmes. Thankfully, they caught him before. They found a military arsenal in his home, and notebooks, where he planned to do more damage by attacking his superiors, and also at least the wife of one them. He also said it to them: \"You're lucky you got me, because i would have gotten you\".\n\nSo a kinda serial-killer, or at least a wannabe-one (a big weirdo anyway), who was actually a cop nagging the police and investigating on his own crimes at the same time, planned to kill his \"friends\" investigating on his case. \n\nThere is not a lot of source as I said. Wikipedia is rather short - and it happened almost 40 years ago. It made some fuzz at the time but it's kinda forgotten (with the exception of the movie released last year). Here are a few in french, though.\n\nAn article released last year about a guy Lamare planned to kill : I was on the list of the Oise killer : _URL_0_\nA global overview on Wikipedia : _URL_2_\nA well done documentary, very detailed : _URL_1_\nAnd the movie *La prochaine fois je viserai le coeur*. I don't know what its worth, haven't seen it."
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Rodrigo_Lara_Bonilla",
"http://www.nytimes.com/1995/06/26/world/reputed-head-of-the-mafia-is-arrested-in-palermo-chase.html"
],
[],
[],
[
"http://www.popsci.com/article/technology/radio-tecnico-how-zetas-cartel-took-over-mexico-walkie-talkies",
"https://books.google.com/books?id=fn_gAAAAMAAJ&q=C.+Lauer+Ward+governor+anderson+starkweather&dq=C.+Lauer+Ward+governor+anderson+starkweather&hl=en&sa=X&ei=vVNaVe7NAcOggwSukYDwAQ&ved=0CE0Q6AEwCQ"
],
[
"http://www.limpartial-andelys.fr/2014/11/22/les-andelys-%C2%AB-jetais-sur-la-liste-du-tueur-de-loise-%C2%BB/",
"https://www.youtube.com/watch?v=_F8tr5TG1S4",
"http://fr.wikipedia.org/wiki/Affaire_Alain_Lamare"
]
] |
|
rrr9p
|
every time someone brings up a major political issues (war, rising gas prices, housing market, medical costs, etc), people almost always point the finger at the president and blame him for everything. but really, which issues are out of his hands and which can he really take action on?
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explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/rrr9p/eli5_every_time_someone_brings_up_a_major/
|
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" > war\n\nThe president has complete control over the US military. That's assuming you mean \"war\" in the contexts of the recent wars, even though technically they haven't really been wars - war can only be declared by Congress, and it hasn't done so since WWII.\n\n > rising gas prices\n\nNot a damn thing he can do about those. They're controlled by OPEC and, to some extent, US refineries.\n\n > housing market\n\nNothing at all to do with the President. Point fingers at Bernanke (Chairman of the Federal Reserve) or the S & P for that, if anyone. Then again, Obama was the one who nominated Bernanke for another term in that position, so in that way you could shift the blame to him, albeit indirectly.\n\n > medical costs\n\nThis is a tricky one. The president can't formally introduce legislation, but he can suggest it, and in most cases he has the final say as to which bills pass and which don't. And in that regard, he's somewhat responsible for health-related legislation, like all other legislation. Having said that, his power in that area is hugely mitigated by the fact that Congress are the ones who need to suggest, approve, and pass a bill before the president can sign or veto it. "
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[] |
[] |
[
[]
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||
68ekfu
|
how can everybody's internet go through the same fiber optic cable at the same time?
|
I get that bits of data are transferred through fiber optic cables as pulses of light. How can the bits of a certain person not mix with another's?
--------------------------------------
edit:
Thanks for the great replies everyone. I can summarize what everyone said as follows:
1- Data are sent as packets of bits, each having the sender and receiver address included. These packets are a predetermined length of digital signals or predetermined format. That's how different packets not mix with each other.
2- Packets take turns going through the same channel, not being transmitted at the same time. It is just so fast that we perceive it to do so.
3- Fiber optic cables have numerous fibers in them, each single fiber can have different communications channels with each being a different frequency of light (thousands).
4- This means that an optic fiber is a very very large highway containing thousands of lanes (wave lengths), in each lane data of different people can travel sequentially as very fast cars (discreet packets of data). One optic fiber cable contains many of these super massive highways.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/68ekfu/eli5_how_can_everybodys_internet_go_through_the/
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"Modern fiber cables can contain up to a thousand fibers in a single cable. And often times we have many cables packed together into a larger cable, though those are mostly underground.",
"Whether it's fibre optic or copper doesn't really matter.\n\nWhenever you visit a web page, for instance, the data you send and receive is cut up into little pieces (packets). Each packet, much like a letter, has a destination address. These packets are sent from your computer to the nearest router. The router inspects the address and figures out where to send the packet to. The next router along the path does the same thing, and the next one, until the packet reaches its destination.\n\nAlong that route, the packet will sometimes travel across a copper wire, a fibre optic cable, or maybe even some kind of wireless link. The point here is that it doesn't batter how the packet is sent. What matters is that the internet is reliable enough that most of these packets arrive at their destination in a timely manner.\n\nFor the most part, these packets are sent and moved one after another. Just like on a highway, there are many packets in a row all going roughly the same direction. Some might take a turn and get off that highway to go elsewhere. Some highways have mutiple lanes, meaning that several packets (or cars) can be roughly in the same place at the same time. This is accomplished, for instance, by transmitting different \"lanes\" in different colours. This too is pretty much technology independent. You can send multiple signals along a copper wire, or a fibre optic cable or through the ether.\n\nIf you think that's magical, then try to think about cable TV: you have many channels on cable TV, but only one cable. It's the same thing as \"everybody's internet\" going through one fibre optic cable. This is called *multiplexing*.\n",
"How do all the letters in the mailman's bag don't get mixed up?\n\nThey are each in an envelope with a sender and recipient address.\n",
"Current technology allows about two terabytes/second transmission speed. Couple this with multi-frequency piggy-backing, and you can have over 40 different freqs on the same fiber, all carrying a two-terabyte package.\n\n\n_URL_0_",
"Because all the data is not sent at truly the same time. They are sent in chunks (packets) one after the other. Each packet has a header which contains the length, destination address, source address and so on.\n\nSo the router knows “the next 50 bytes should go to the address 123.123.123.13” and sends it there."
]
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|
803rsi
|
how does vsync prevent screen tearing?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/803rsi/eli5_how_does_vsync_prevent_screen_tearing/
|
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"Vsync is basically vertical synchronization. When ever you play a game without vsync and move your mouse, you can see tearing where there is a lot of movement because your computer screen displays the image in in horizontal lines, which is too fast for the eye to see, so we see it as a whole image. Since your video card works through countless amounts of equations, it might have a hard time keeping those lines on synch, depending in which game you're playing, your settings, and hardware. \nHere's a video that demonstrates the workings of a variety of screens: _URL_0_",
"Screen tearing happens when your video card starts drawing a new frame while you're in the middle of refreshing the screen. Vsync forces the image on the screen to only refresh in sync with a new screen."
]
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|
[] |
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||
1fbo8g
|
how is it theoretically possible in the future to clone mammoths?
|
I was looking at this here [thread](_URL_0_) and there was a comment saying something about cloning it being possible. I was hoping to get a basic idea as to why this is the case. Wasn't sure if I should've posted it on /r/askscience as it would have been a more complex answer that my little brain might not be able to handle
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1fbo8g/eli5_how_is_it_theoretically_possible_in_the/
|
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"I'm not a scientist, but I can parrot Terry Pratchett's \"Science of Discworld\".\n\nThe idea is that a mammal's genome is like an incomplete recipy. It tells you what to put together to make the cake mix. But it already assumes that you know at what temperature you need to preheat your oven and how long to bake it.\n\nUntil we figure that out we can't clone mammoths. Since we've got no mammoths to gestate these clones in.",
"I'm not an expert, but there are a couple of reasons. The first is that DNA lasts longer than we used to think - under the right circumstances. And in the case of the wooly mammoth it is not unusual to find frozen remains. Why do we find frozen mammoth remains so often? Well, that's related to the second reason:\n\nMammoths are closely related to modern elephants. They were wooly because they lived in northern, snowy climates. Sometimes they died in places that have remained frozen until today.\n\nBecause they are related to elephants, in theory we can take their DNA and place it inside an elephant embryonic cell, an egg. We could then place this egg inside a mother elephant. It should grow normally. The mother might wonder why her baby was so hairy, but it would look like an elephant to her.\n\nDinosaurs lived much farther in the past. But if by some miracle we did get a complete set of DNA for some dinosaur, what could we get to hatch it? Much harder all around."
]
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[] |
[
"http://www.reddit.com/r/pics/comments/1fa9hb/mammoth_blood/"
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[],
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|
8atuhw
|
why are there so many blondes in sweden?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8atuhw/eli5_why_are_there_so_many_blondes_in_sweden/
|
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"Having less melanin allows your body to take in more sunlight which can be used to create vitamin D which the human body needs. In warm places like Africa sunlight is abundant and you are far more likely to get skin cancer from exposure to sunlight unless your skin has some protection like melanin. In the far north like Sweden cancer from exposure to the sun is far less likely to be an issue while there is a need to allow more sunlight into the skin. Blonde hair is the lack of pigment in the hair just like blue eyes come from a lack of pigment in the eyes. A long time ago someone was born with blond hair and pale skin and this proved over time to be beneficial in environments in the far north so their descendants kept these mutations. The Swedes are some of their decendants."
]
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[] |
[] |
[
[]
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2kukm9
|
What was the first instance of photographic evidence being used in court?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2kukm9/what_was_the_first_instance_of_photographic/
|
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"This may not be the earliest but it's definitely an early example. The case is *Marcy vs. Barnes* in the Supreme Court of Massachusetts, 82 Mass. 161, October 1860. It's basically a case where one of the parties claimed that his signature on a promissory note was forged. High resolution photographs were taken of the supposed forged signature and an expert in handwriting analysis was brought in to analyze those photos.\n\nIt was argued in court that the photographs shouldn't be admitted as evidence. This was the court's decision regarding that:\n\n > The magnified photographic copies of the genuine signatures of the defendant, and of the disputed signature, which was submitted to the inspection of the jury, were, we think, in connection with the testimony of Mr. Southworth, admissible in evidence. Assuming it to be true, as he testified, which yet was a fact first to be considered and determined by the jury, that the copies were accurate in all respects, excepting only in relation to size and color, they were capable of affording some aid in comparing and examining the different specimens of handwriting which were exhibited on the trial. It is not dissimilar to the examination with a magnifying-glass. Proportions are so enlarged thereby to the vision, that faint lines and marks, as well as the genuine characteristics of handwriting which perhaps could not otherwise be clearly discerned and appreciated, are thus disclosed to observation, and afford additional and useful means of making comparisons between admitted signatures and one which is alleged to be only an imitation. Under proper precautions in relation to the preliminary proof as to the exactness and accuracy of the copies produced by the art of the photographer, we are unable to perceive any valid objection to the use of such prepared representations of original and genuine signatures as evidence competent to be considered and weighed by the jury.\n\nIt's entirely possible that photography was used or attempted to be used in cases prior to this but I haven't come across anything in the literature. There is an article titled *The Legal Relations of Photography* from the January 25, 1873 issue of The Albany Law Journal, 7 Alb. L.J. 50. It's clear that photography wasn't well understood, by legal scholars at least, at the time as there's mention of a dead person's final view of the world being imprinted on the retina for a while and perhaps accessible via a photograph.\n\nHowever it mentions two other cases in addition to *Marcy*. One is *The Taylor Will Case*, a probate case in the State of New York from 1871 (10 Abb. N.S. 300) where photographic evidence was disallowed because it was considered secondary evidence. There's also *Ruloff's Case*, also from New York in 1871 that allowed photographs of deceased robbers for identification purposes (45 N.Y. 213).\n\nSo while these are later cases, it shows, and the article agrees, that there hadn't really been enough of these in front of courts to come to a decision at the time whether photographic evidence should be allowed or what conditions should be set to allow them."
]
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[] |
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4mpbd0
|
how do animals (with bullying type personality) instinctively change their personality to protect their puppies, cubs, etc when they become parents?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4mpbd0/eli5how_do_animals_with_bullying_type_personality/
|
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"What exactly do you mean by an animal with a bullying personality type? Do you have any examples?\n\nBut generally speaking you don't have to do anything to trigger the maternal instinct, that's what makes it an instinct.",
"Well view it in terms of evolutionary success. If an aggressive animal kept it's same demeanor and killed it's cubs/puppies out of aggression or simply pushed them out of its area due to territorial defense then that gene pool wouldn't be reproductively successful. Therefore those whom have the demeanor to protect their young will be way more successful in terms of having offspring that mature and reproduce. The animals whom have the genetic disposition to protect and nuture their young while being able to maintain a bullish stance to predators or intruders will always be more successful in terms of survival of their gene pool so they exist today because their ancestors were successful in protecting their young and they are the living product of their ancestors. (This applies to mainly mammals, plenty of other animals go with the plan of mass producing young and abandoning them knowing some will still survive i.e. reptiles, fish)\n\nSo in short it's very possible individual mothers(in terms of animals such as bears, wolves, dogs) exist that are aggressive to their young but they will never be the majority because their young are more likely to perish before passing on that gene pool.",
"Just like new human mothers release hormones to keep them from killing their children for waking them up 10 times a night (I'm serious, that's pretty much why) animals do too. The hormones are what initially creates such a strong bond between mother and child and thus creating a strong protector instinct. It is pure genetics for a mother to literally lay her life on line for her child (this ensures the continuation of the species if you want to get all sciency about it). But basically just hormones. "
]
}
|
[] |
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|
louv2
|
At the atomic level, what determines the qualities of different metals?
|
It's clear enough that the ability to form metallic bonds is responsible for the properties of metals vs nonmetals. Further it seems pretty clear that electronegativity/atomic radius determines that ability. But what makes, for instance, iron harder than copper? Why can I bend a lead bar with my bare hands but an iron bar is totally immobile?
What, on the atomic level, is going on with these properties?
Furthermore, why is gold the most electronegative metal? It's apparent that gold is the most corrosion resistant and electronegative among the metals, but why is it that gold is a metal *while being more electronegative*, actually a smaller nucleus, than many nonmetals (Phosphorus and carbon, for instance)?
|
askscience
|
http://www.reddit.com/r/askscience/comments/louv2/at_the_atomic_level_what_determines_the_qualities/
|
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"The property of lead you're describing is due to its ductility and malleability (malleable being somewhat loosely defined). Hardness is also related to these two, per its normal definition as a material's resistance to local deformation. Several differences in materials can give rise to more or less ductility. [Crystal structure](_URL_2_) is probably the most familiar to people. Face Centered Cubic usually produces the most ductile materials because of the close packing. Body Centered Cubic metals are not close packed and are usually less ductile. \n\nDuctility and malleability are related to the ability of a metal to plastically deform. There's two types of deformation when we're talking about materials: elastic, and inelastic (sometimes called plastic). Elastic deformation is what it sounds like: after you stretch it out, it comes back to its original shape and size. Elastic strength is related to the strength of the bonds in the material. Plastic deformation is permanent deformation, which is what we're interested in. \n\nPlastic deformation is associated with the movement of dislocations in a material. A [Dislocation](_URL_0_) is an irregularity in the structure of a crystalline material. There are two basic types: edge and screw dislocations. You can see the wiki article for some good pictures. When it comes down to it, they're just atoms bonded in a pattern that stretches the bonds a little instead of being in their lowest energy state, the perfect crystal. \n\nThese dislocations create shear stresses in the material. They can also move in the crystal when it is stressed. Plastic deformation can be described as the movement of dislocations - its easier to move the dislocations than to break the material. This movement produces changes in the crystal, which can be seen as the large scale deformation.\n\nEDIT: Oh right, I was going to write something about [Grains](_URL_1_). Metals are not usually one big crystal; they're actually a bunch of little crystals all smashed together. These little crystals are called grains. Their size and shape can greatly affect the properties of a material. Smaller grains can slide past one another much more easily, which can make a material more ductile. Non-isotropic grains, long skinny ones for example, can produce greater ductility in one direction than in another (parallel vs perpendicular stress compared to the grain direction). ",
"All of the responses so far are basically correct in the way they describe the metallurgy, but none of them answer your basic question—why does one metal behave differently from another? It is true, as others have noted, that the crystal structure affects behavior, but a more important effect for your particular example of iron v. copper v. lead has to do with the strength of the bonding. Metals with very strong interatomic bonding tend to be very stiff (resistant to elastic deformation) and very strong (resistant to plastic, or permanent, deformation). Since bond strength is also correlated with melting temperature, the high melting-point (refractory) metals such as tungsten also tend to be very strong. So, for example, of the three metals you point out, iron has the highest melting point and is the strongest, while lead has the lowest melting point and is the weakest.\n\nAll of the effects mentioned by others (crystal structure, grains, dislocations, etc) are basically second-order corrections on this basic fact.",
"The property of lead you're describing is due to its ductility and malleability (malleable being somewhat loosely defined). Hardness is also related to these two, per its normal definition as a material's resistance to local deformation. Several differences in materials can give rise to more or less ductility. [Crystal structure](_URL_2_) is probably the most familiar to people. Face Centered Cubic usually produces the most ductile materials because of the close packing. Body Centered Cubic metals are not close packed and are usually less ductile. \n\nDuctility and malleability are related to the ability of a metal to plastically deform. There's two types of deformation when we're talking about materials: elastic, and inelastic (sometimes called plastic). Elastic deformation is what it sounds like: after you stretch it out, it comes back to its original shape and size. Elastic strength is related to the strength of the bonds in the material. Plastic deformation is permanent deformation, which is what we're interested in. \n\nPlastic deformation is associated with the movement of dislocations in a material. A [Dislocation](_URL_0_) is an irregularity in the structure of a crystalline material. There are two basic types: edge and screw dislocations. You can see the wiki article for some good pictures. When it comes down to it, they're just atoms bonded in a pattern that stretches the bonds a little instead of being in their lowest energy state, the perfect crystal. \n\nThese dislocations create shear stresses in the material. They can also move in the crystal when it is stressed. Plastic deformation can be described as the movement of dislocations - its easier to move the dislocations than to break the material. This movement produces changes in the crystal, which can be seen as the large scale deformation.\n\nEDIT: Oh right, I was going to write something about [Grains](_URL_1_). Metals are not usually one big crystal; they're actually a bunch of little crystals all smashed together. These little crystals are called grains. Their size and shape can greatly affect the properties of a material. Smaller grains can slide past one another much more easily, which can make a material more ductile. Non-isotropic grains, long skinny ones for example, can produce greater ductility in one direction than in another (parallel vs perpendicular stress compared to the grain direction). ",
"All of the responses so far are basically correct in the way they describe the metallurgy, but none of them answer your basic question—why does one metal behave differently from another? It is true, as others have noted, that the crystal structure affects behavior, but a more important effect for your particular example of iron v. copper v. lead has to do with the strength of the bonding. Metals with very strong interatomic bonding tend to be very stiff (resistant to elastic deformation) and very strong (resistant to plastic, or permanent, deformation). Since bond strength is also correlated with melting temperature, the high melting-point (refractory) metals such as tungsten also tend to be very strong. So, for example, of the three metals you point out, iron has the highest melting point and is the strongest, while lead has the lowest melting point and is the weakest.\n\nAll of the effects mentioned by others (crystal structure, grains, dislocations, etc) are basically second-order corrections on this basic fact."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Dislocation",
"http://i.imgur.com/a3fgM.gif",
"http://en.wikipedia.org/wiki/Cubic_crystal_system"
],
[],
[
"http://en.wikipedia.org/wiki/Dislocation",
"http://i.imgur.com/a3fgM.gif",
"http://en.wikipedia.org/wiki/Cubic_crystal_system"
],
[]
] |
|
4jkhvm
|
What were insults like during battles in medieval Europe?
|
How much shittalking was done, if any, on the battlefield?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4jkhvm/what_were_insults_like_during_battles_in_medieval/
|
{
"a_id": [
"d37gvmr"
],
"score": [
27
],
"text": [
"An interesting example of this can be found in the 1424 Battle of Verneuil, between the Duke of Bedford (with largely English and Norman forces, I believe) and forces of the Dauphin Charles, including, Spaniards, Lombard Cavalry and, notably, Scottish forces under Douglas. \n\nContemporaries noted that this was a particularly fiercely fought battle and that, in particular, the Scots were slaughtered (rather than being taken prisoner after the English had won the battle). Jones notes that the tone of the battle was particularly unchivalric. The Dauphinist side had failed to keep the terms agreed for the battle (date, time etc.), and the English side was offended and smaller: they had perhaps 8,000 men compared with maybe 15,000 opposition. The new position at Verneuil was ideal for the Lomabrd cavalry whereas the original situation agreed had been better for the English, who would have fought defensively. The contemporary chroniclers note how offended the Duke of Bedford was at this slight. The involvement of the Scottish forces was even more offensive. A truce between England and Scotland had come into effect on the 1st May (I believe) which meant that the Scots would no longer fight with the French- but there was a loophole allowing Scottish forces already in France to stay. The English were offended at the Scottish presence. \n\nThis makes the levels of insults and chivalric challenges perhaps *unusual*, but it is not clear how far so. It seems that the English side and the Scottish forces, arrayed before the battle, hurled challenges, presumably with insults, at each other: this was to be a fight to the death, and the Scottish- oath breakers- did not deserve proper chivalric protocol. \n\nSo what were these challenges like? \n\nOne chronicle reported that Bedford mockingly invited Douglas to drink with him, and Douglas replied 'he would be delighted, since he had been unable to find him in England, and had come to France to look for him'. This was apparently a reference to a previous raid of 1417. The diplomatic context was therefore important. \n\nI don't know of any more local insults that were recorded at Verneuil, though I imagine that some were far more vulgar. Somebody else has already mentioned Joan of Arc. According to contemporary chroniclers, she was twice called 'whore' or 'whore of the Armagnacs'. This seems entirely possible- yet it is also important to stress that Joan wasn't a usual combatant. \n\nFrom what I've read, which mostly concerns elite communication (this was clearly far more likely to be recorded), insults were usually based on breaches of chivalric protocol. The Dauphinist murder of John the Fearless, for example, or the Burgundian 'betrayal' of the French crown. These were serious accusations that could change the ways that battles were fought (consider the slaughter of the Scots). More prosaic insults are less frequently recorded. "
]
}
|
[] |
[] |
[
[]
] |
|
kd6zu
|
Can someone explain the concepts of opioids and narcotics and their use in pain management?
|
I've been prescribed medications of various types in my life. Sometimes these are opioids, sometimes these are narcotics, sometimes they are both, sometimes they are neither.
Can someone explain the concepts behind opioids and narcotics, and how they are related or excluded from one another? How is an opioid non-narcotic? How is a narcotic not of the opioid class of pharmaceuticals?
|
askscience
|
http://www.reddit.com/r/askscience/comments/kd6zu/can_someone_explain_the_concepts_of_opioids_and/
|
{
"a_id": [
"c2jbw22",
"c2jc80r",
"c2je5cu",
"c2jbw22",
"c2jc80r",
"c2je5cu"
],
"score": [
6,
2,
4,
6,
2,
4
],
"text": [
"In a nutshell, [opiates/opioids](_URL_1_) are any drugs that act on/bind to [opioid receptors](_URL_2_). Opioid receptors are protein molecules embedded in the membrane of many cells within the central and peripheral nervous system (CNS/PNS) - so-called because they bind opioids; of which there are multiple endogenous forms (e.g. endorphins, enkephalins). \n\nA [narcotic](_URL_2_), however, is a bit more difficult to define. To my knowledge, any psychoactive drug that induces sleep is defined as a narcotic (in agreement with the wiki-page). The nomenclature hints at this as 'narco' is from the greek root 'narke' - a prime example is [narcolepsy](_URL_0_). So, many opioids are actually also classed as narcotics (see the wiki-link for examples).\n\nHope this helps.\n",
"In addition, you might also be thinking of non-narcotic *analgesics*. A non-narcotic analgesic is a painkiller that derives its action not from agonism of an opioid receptor. Acetaminophen is an example of one. \n\nYou can also have a non-narcotic opioid (using \"inducing sleep/stupor\" as the definition for narcotic). This would be a drug that acts at the opioid receptor but fails to induce sleep/related effects. Loperamide is an example of a non-narcotic opioid in this case. Because it does not enter the brain well, it does not produce analgesic effects. ",
"Hey just found this thread, I will be back shortly to elaborate.\n\n\n\n(this is my expertise) ",
"In a nutshell, [opiates/opioids](_URL_1_) are any drugs that act on/bind to [opioid receptors](_URL_2_). Opioid receptors are protein molecules embedded in the membrane of many cells within the central and peripheral nervous system (CNS/PNS) - so-called because they bind opioids; of which there are multiple endogenous forms (e.g. endorphins, enkephalins). \n\nA [narcotic](_URL_2_), however, is a bit more difficult to define. To my knowledge, any psychoactive drug that induces sleep is defined as a narcotic (in agreement with the wiki-page). The nomenclature hints at this as 'narco' is from the greek root 'narke' - a prime example is [narcolepsy](_URL_0_). So, many opioids are actually also classed as narcotics (see the wiki-link for examples).\n\nHope this helps.\n",
"In addition, you might also be thinking of non-narcotic *analgesics*. A non-narcotic analgesic is a painkiller that derives its action not from agonism of an opioid receptor. Acetaminophen is an example of one. \n\nYou can also have a non-narcotic opioid (using \"inducing sleep/stupor\" as the definition for narcotic). This would be a drug that acts at the opioid receptor but fails to induce sleep/related effects. Loperamide is an example of a non-narcotic opioid in this case. Because it does not enter the brain well, it does not produce analgesic effects. ",
"Hey just found this thread, I will be back shortly to elaborate.\n\n\n\n(this is my expertise) "
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Narcolepsy",
"http://en.wikipedia.org/wiki/Opioids",
"http://en.wikipedia.org/wiki/Opioid_receptor"
],
[],
[],
[
"http://en.wikipedia.org/wiki/Narcolepsy",
"http://en.wikipedia.org/wiki/Opioids",
"http://en.wikipedia.org/wiki/Opioid_receptor"
],
[],
[]
] |
|
216ymd
|
Why do we call the German Empire during the Inter-war period the Weimar Republic?
|
To my understanding it was still self identified as the Deutsches Reich within Germany. Wouldn't it be appropriate to call it the German Empire, or the German Republic? Is there some purposeful attempt to separate the Weimar Republic from the Empire so as to distance it from Nazi run Germany?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/216ymd/why_do_we_call_the_german_empire_during_the/
|
{
"a_id": [
"cga7f03",
"cgafp2c",
"cgagm7f",
"cgahail"
],
"score": [
11,
7,
4,
10
],
"text": [
"It was still officially referred to as Germany or the German state/realm by people in high office, no one to my knowledge called it Wiemar. It got that name because in the immediate aftermath of WW1 there was ongoing violence between the various radical political groups, so when it came time for the new national assembly to meet, they choose to do it in the city of Wiemar to avoid the ongoing street fighting in Berlin. ",
"Translating \"Reich\" directly to \"Empire\" is problematic.",
"The name is used for convenience of historical discourse. The constitution of the Weimar Republic was very different from the monarchy that existed before as well as from the Hitler dictatorship and East/West Germany which followed later. So it is convenient to have a separate name for it.\n\nIn any case, the official name of the Weimar Republic was still \"Deutsches Reich\" - German Empire. And at the time, no one would have referred to the country as Weimar Republic - it was simply Germany. \n\nOP is right that there is probably some purposeful attempt to separate the Weimar Republic from Nazi Germany -- in German self-awareness, there is a big line between the \"good\" part of the country's history (before 1933) and the \"bad\" part (after 1933). However, the monarchy that preceded the republic was also called Deutsches Reich, so it's not just that.\n\nTo complicate this further, the English word Empire does not have the same connotations as the German word Reich. Because of the British Empire, the English word is associated with conquest and colonialism, which does not apply to \"Reich\" at all. The word is basically untranslatable because its meaning is tightly tied to the history of the various German states called Reich.",
"It's a convenience term that was established to remove the ambiguity of the term \"Deutsches Reich\", which covers different periods. So, instead of saying \"Deutsches Reich under the pre-revolutionary constitution\", we say \"Kaiserreich\" (\"Emperor Realm\"). \"Weimar Republic\" or \"Weimarer Republik\", in turn, refers to the post-revolutionary period between the proclamation of the first democratic constitution in the city of Weimar in 1919 up until the establishment of the Nazis' dictatorship in 1933, which of course was yet another politically distinct iteration of Deutsches Reich.\n\nLikewise, to distinguish pre-Unification West-Germany from the present post-Unification republic, the term \"Bonner Republik\" or \"Bonn Republic\" is often used, because Bonn served as capital during that time. This is helpful because, technically, East Germany broke up into five states which joined the (Western) Federal Republic of Germany, so it's the same constitution/state as before. \"Berliner Republic\" or \"Berlin Republic\" can be used to refer to post-Unification Germany, but it's less common, because it's simply the present and such a distinction is rarely necessary in discourse."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
3h4nia
|
if you move can you take your homing pigeons with you, or do they always return to your old house?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3h4nia/eli5_if_you_move_can_you_take_your_homing_pigeons/
|
{
"a_id": [
"cu46cwx"
],
"score": [
25
],
"text": [
"If you don't let your homing pigeons out, they eventually identify where they currently are as their 'home'."
]
}
|
[] |
[] |
[
[]
] |
||
3vbl7m
|
with apple making everything proprietary anyway, wouldn't they profit from adding a smaller headphone port, and sell proprietary headphones?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3vbl7m/eli5_with_apple_making_everything_proprietary/
|
{
"a_id": [
"cxm17v9",
"cxm18zo"
],
"score": [
2,
2
],
"text": [
"Sure. Except they already have that with the lighting connector. Why should they invent a second thing that does the exact same function as a thing they have already invented. Headphone makers can simply add a lighting connector to their headphones. \n\nIt does pose a challenge of charging while listening, but that can be solved by a simple splitter. ",
"Well, no, because there's a universal standard for headphones that predates their entry into the market, so it would be a significant impediment to adoption of their hardware."
]
}
|
[] |
[] |
[
[],
[]
] |
||
5jmyu5
|
why do we hate killers and thieves but we love killing and stealing in videogames?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5jmyu5/eli5_why_do_we_hate_killers_and_thieves_but_we/
|
{
"a_id": [
"dbhee9i",
"dbhelp8",
"dbhhz1s",
"dbhi56y",
"dbhnzhq"
],
"score": [
27,
2,
12,
2,
3
],
"text": [
"Bad things are more fun when we do them than when other people do them. And in a videogame, these actions are victimless so it removes the moral issues which makes it enjoyable for those of us that don't actually want to hurt other people.",
"We're not doing them in real life - we blow off steam when we do this in video games so it's socially acceptable",
"Tragedy is when something bad happens to me, comedy when it happens to you.\n\nFortunately, in video games, there is no \"you\" to suffer from the thieving and murdering gamers of the world. Pixels feel no pain.",
"Generally in most of the video games you are in the control of everything and stealing, killing etc. doesnt effect you that much because there is **nothing to lose**.If you die you can simply reload. \n\nThink about this way; i remember how carefull people was when playing diablo 3 in hardest mode because there was no respawn, if you die its game over. No reload or something else. Even when it was not \"gg wp\" situation because you can simply create new acc and now compare to that real life + education you had. The sense of righteousness.\n\nThanks for reading. (Not native speaker sorry if i made mistake[s])",
"People love to have a sense of control, but they *hate* when others have more control than them.\n\nIf you stole a dollar from me, you'd have control in that situation. But you'd be taking away my control of the dollar. It's unfair since you have more control than I do, so it's considered bad to steal.\n\nVideo games generally give you lots of control—we love to steal in video games because we *can*. The more you're able to do something the way you want, the more you'll enjoy the game. And there's no real person losing any control when you do. (In PvP games the loser still controls how well he plays.)\n\nEven when the game introduces consequences for stealing, it's usually something the player can control. You can control how stealthily you steal to avoid getting caught, or you can control how well you fight off the guards or cops that come after you. You wouldn't try to steal as freely in real life because you probably couldn't keep the consequences under control."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
||
784tpp
|
why are benzos the go-to for a lot of mental issues?
|
I've heard (forgive me if I'm wrong) that for many mental conditions a paramedic, ambulance, or hospital may be called for, benzodiazepines (and benzothiazepine?) are one of the main methods of treatment.
Why is this the case? I'd assume given how complex the human brain is that anything which can shut down so many processes at once would be unhealthy. What makes these particular receptors unique to their role in medicating individuals?
Thank you for any help and information!
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/784tpp/eli5why_are_benzos_the_goto_for_a_lot_of_mental/
|
{
"a_id": [
"dor3kf2",
"dor5qpc",
"dor6o9b"
],
"score": [
14,
5,
2
],
"text": [
"They're a tranquilizer. So in any case where there's too much brain activity, or a patient is too agitated, you give them benzo. Quick fix for seizures, panic attacks, anxiety, etc. It's like turning down the volume on the brain.",
"They work quickly and like you said basically shut down the brain for a while. I'm not sure how they do with long term treatment but when you have someone who is agitated and violent, it's safer to go ahead and basically turn them off for a few hours before they hurt themselves or someone else. From there you can formulate a more reasonable treatment plan but the immediate goal is to keep everyone safe. That's why they are used by EMS/hospital staff quite often from what I can tell. \n\nBasically a dose of \"calm the hell down for a minute\"\n\n",
"Also, when a person is acting “crazy”, the doctors cannot always tell if it’s actual psychosis, street drugs, or delirium. After a good nap the street drugs will have worn off. When they wake up they will no longer be “crazy”, and that will help with the diagnosis. Plus, lack of sleep truly can make you a crazy fucking asshole. I think that is the ICD-9 medical diagnosis. I might be wrong, but I’m not. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
8tl78k
|
how come a wi-fi repeater uses the same channel as the router?
|
How does a WiFi repeater uses the same channel (same frequency, to my understanding) as the source of it's signal (the router, probably), especially in cases where both the repeater transmitter and the router transimitter are both in reception range?
Wouldn't it cause interferences?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8tl78k/eli5_how_come_a_wifi_repeater_uses_the_same/
|
{
"a_id": [
"e18cwxm",
"e18d0ut",
"e18f0ls"
],
"score": [
2,
2,
2
],
"text": [
"A WiFi repeater does exactly what it says in the name, it repeats. A repeater listens to every message and then rebroadcasts the exact same message with the exact same parameters. It has no smarts to it and just tries to pass the message. A basic repeater will cause message collisions and cut your effective WiFi bandwidth by at least 50% because half the time is spent just repeating messages.\n\nA WiFi range extender is generally smarter and will setup a network on a different channel with the same SSID. It will take any messages it hears from the main router and rebroadcast them on its channel. This is much better as it doesn't clog up the main channel with redundant messages",
"The range of channels for 802.11b/g/n in the U.S. is 1 through 11. People typically use 1, 6, and 11 for minimal interference.\n\nSuppose your main router uses channel 1.\n\nYour repeater uses channel 1 to talk to your main router, and it often uses another channel, like channel 11, to talk to devices closer to the repeater.\n\nDoes that make sense? If you take your laptop near the main router, you're connecting to it using channel 1. Then if you walk closer to the repeater, now you're connecting to the repeater using channel 11 and the repeater is connecting to the main router using channel 1.\n\nDoes that generate interference? Yes, but it's no difference from the interference you get when you have 3 laptops, a gaming computer, an Echo, a Chromecast, a smart fridge, and 17 other wireless devices all sharing the same channel too.\n\nKeep in mind that there's \\*always\\* interference. Wi-fi is always working around it. It's only a question of how much.",
"Personally I would never use a wireless extender because they are not very reliable. What I would use is a wired extender. One that connects to the first router via ethernet cable and works as a second wifi connection point. This is known as bridging. In this case you can change the bandwidth and even SSID and it will work just fine. Or you can even use the same bandwidth and same SSID and keep it far enough from the first wifi so the signals do not interfere.\n\nIn this form you can get any cheapo regular router and turn it into an extender based on the first router. You can even extend from the second extender to a third extender and to a fourth and so on. And since they already have ports built into them you can also connect other devices to them through ethernet wire. I've done a six routers deep bridge and my connection was as fast as if it was connected directly to the first router.\n\nSetting up the routers into extenders can be something that is not for the faint of heart specially if you want the dhcp server to be configured by the first router. This is preferred otherwise each router can be considered its own private LAN that cannot connect to the computers on the other extenders/lans.\n\nAlthough, there are some newer routers with a built in configuration option to set them as slave extenders. I'm no expert on any of this. It's just stuff I learned on my own. So if I made any mistakes on any of this jargon and information, please correct it."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
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