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5ghmg1
|
how does audio get balanced?
|
For example, I was listening to as song where there was a saxophone and guitar duo. The saxophone dominated the left speaker and the guitar dominated the right. How does your sound system differentiate which speaker to play out of?
Other examples of this can be found in 3D soundscapes in gaming. I've never fully understood how this works.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5ghmg1/eli5_how_does_audio_get_balanced/
|
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"Most audio is recorded in two audio streams: Left and Right. This makes sense because we only have two ears.\n\nSince there are two different streams, you get one per speaker. To make the audio directional, you just have it louder in one side compared to the other. This is exactly how our ears work to determine where a sound is coming from. 3D sound positioning in gaming works in a similar way.\n\nIn a more complicated speaker system, you can have more than 2 audio tracks."
]
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|
[] |
[] |
[
[]
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|
3pho9p
|
why can't humans invent machines that activate our muscles without us having to do exercise?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3pho9p/eli5_why_cant_humans_invent_machines_that/
|
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"We can and we have. There are machines that exercise the muscles of comatose patients to stop them atrophying and you can get gadgets that use electricity to supposedly exercise muscles - e.g. Slendertone.",
"Surely it's more efficient to just exercise. I mean that as a serious answer - I imagine if anyone was setting out to invent this, they'd give up pretty quickly!\n if your muscles are moving, you'll feel them just as much as if you were moving them yourself. It's not as though you could just lie there and watch tv calmly while your muscles are flexing and working . You'd still get sweaty and tired and sore - so cut out the middleman of the machine you're thinking of building, and use the muscle-controlling machine in your head instead. "
]
}
|
[] |
[] |
[
[],
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|
lt6vp
|
Do two electrons have to interact?
|
I was wondering, what would happen if I were to just put two electrons in an empty space?
Does Coloumb's law even work at these scales?
|
askscience
|
http://www.reddit.com/r/askscience/comments/lt6vp/do_two_electrons_have_to_interact/
|
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"Yes, two electrons separated by any distance will interact electromagnetically, though it'll take a time of that distance divided by the speed of light for the two to notice each other's existence.",
"Yes, two electrons separated by any distance will interact electromagnetically, though it'll take a time of that distance divided by the speed of light for the two to notice each other's existence."
]
}
|
[] |
[] |
[
[],
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|
2si8eo
|
When did lower case letters appear in the Roman alphabet?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2si8eo/when_did_lower_case_letters_appear_in_the_roman/
|
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"Lowercase (or minuscule, as one often refers to them in calligraphy, lowercase is a term from printing) was developed (or rather, codified) under the rule of Charlemagne. The Caroline Minuscule hand was developed under the leadership of the English scholar Alcuin of York, after coming to Charlemagne's palace in Aachen and establishing a school there. Alcuin's so called Crowd of Scribes (*turba scriptorium*) were to copy religious texts and disseminate them throughout Charlemagne's newly formed empire, and to do so efficiently they codified rules for the mess that was handwriting and calligraphy in medieval Europe.\n\nTheir invention was the [caroline minuscule](_URL_0_), meant to be easy to read and write, with characters set apart from each other and not joined up (this is called a ligature in calligraphy and typography), and with descenders and ascenders, an innovation taken from the Irish Uncial scripts.\n\nThis writing was the forerunner of minuscule, but it was unlike ours in that Majuscule (uppercase letters) and Minuscule didn't appear together. That, however, soon changed, as the scribes at Charlemagne's court soon began to use Roman capitals (which are all majuscule) to make intricate initals and illuminations. That was the first step to signifying importance and hierarchy with majuscule, and a mixed alphabet.\n\nSource: Meggs' history of Graphic Design (2012); recently took a course on the history of typography; practitioner of calligraphy.\n\nEdit: got my empires somewhat mixed up.",
"According to \"A Guide to Western Historical Scripts from Antiquity to 1600\" (2002) many lower case forms (among others: a, e, d, g, p, q, r) are found in both Half-Uncial and Cursive Half-Uncial in the \"New Roman System of Scripts.\" These scripts were largely derived from old Roman cursive (mostly used before the 2nd century) and developed between the 2nd and 4th century CE. \n\n[Here](_URL_1_), in this simplified comparison of early scripts, you can see many minuscule characters. \n\n[This image](_URL_0_) from the Encyclopedia Britannica also illustrates these scripts. \n\nThe author goes on to say that \"Half-Uncial was to be extremely influential in the development of national hands, in Caroline minuscule and thereby the whole of the Middle Ages.\" For the more information about Caroline minuscule see /u/jabask's excellent post. My only critique would be that minuscule was \"codified\" under the rule of Charlemagne rather than \"developed\" which s/he put in parenthesis anyway. ",
"Can I piggyback on this thread and ask when lowercase letters were added to the ancient Greek alphabet?",
"Minuscule letters started to form between 1st and the 3rd century AD. In paleography this first group are called minuscule cursive, and were completely formed in the s.III.\ne.g: London, british museum, Pap. Lond. 731, ChLA, III, S. 87 (i'll try to upload some pictures)\nDuring the 4rd century this minuscule cursive evolved to a more clear, and comprehensive letter wich is called minuscule antiqua.\ne.g: Manchester, John Rylands Library, Pap. 472 \n\nBefore the Caroline minuscule, we can find the half-uncial, the uncial, the merovingic, visigothic cursive, visigothic \"redonda\" ( < - i don't know the term in english), and merovingic, and other locals typographies.\n\nP.d: I had a paleography exam this monday and I saw myself forced to answer this though I'm not very good at english u-u.\nWhen I get home I'm gonna upload the powerpoints that discuss this theme, in case that anyone is interested.\n\n**edit: _URL_0_ There you have it. In the page 41 it's the first example that i've said. (If anyone is wondering, the lenguage on the ppt is catalan.)\n\nSource: my powerpoints :P, wich came from this bybliography (there's none in english, sorry about that) (I'm not sure what is the best so i give you all):\n-CAVALLO, G (1997) “Entre el volumen y el codex. La lectura en el mundo romano”.\nEn: CAVALLO, G.; CHARTIER, R. (dirs.) Historia de la lectura en el mundo\noccidental. Madrid, Ed. Taurus, pp. 95-133.\n-CAVALLO, G. (1995) “Libros y público a fines de la Antigüedad”. En: CAVALLO,\nG. (ed.) Libros, editores y público en el mundo antiguo. Guía histórica y crítica.\nMadrid, Ed. Alianza Editorial, pp. 109-168).\nFEDELI, P. (1989) “I sistemi di produzione e diffusione”. En: CAVALLO, G.;\nFEDELI, P.; GIARDINA, A. (dirs.) Lo spazio letterario di Roma Antica, vol. II, La\ncircolazione del testo. Roma, Ed. Salerno Editrice, pp. 343-378.\nHOLTZ, L. (1989) “Les mots latins désignant le livre en temps d'Augustin”. En:\nBLANCHARD, A. (ed.) Les débuts du codex. Actes de la journée d'étude organisée à\nParis les 3 et 4 juillet 1985 par l'Institut de Papyrologie de la Sorbonne et l'Institut de\nRecherche et d'Histoire des Textes. Turnhout, Ed. Brepols (=Bibliologia. Elementa ad\nlibrorum studia pertinentia, X), pp. 105-114.\nKLEBERG, T. (1995) “Comercio librario y actividad editorial en el Mundo Antiguo”.\nEn: CAVALLO, G. (dir.) Libros, editores y público en el mundo antiguo. Guía\nhistórica y crítica. Madrid, Ed. Alianza Editorial, pp. 51-108.",
"hi! you may be interested in the following posts\n\ncourtesy of our friends in /r/Linguistics \n\n* [In Latin script, why do lowercase and uppercase generally have different forms, rather than just a difference in size?](_URL_5_)\n\nfrom this sub\n\n* [Where did \"lower case\" letters come from? Why did they get popularized?](_URL_3_)\n\n* [Where did lower case letter come from, why, and why did lower case numbers never come about?](_URL_0_)\n\n* [Where do capital letters come from? What was their original purpose?](_URL_2_)\n\n* [Why did we 'invent' capital letters? When did they first appear and how else have they been used throughout history?](_URL_6_)\n\n* [How did Latin script win over Roman cursive in common writing?](_URL_1_)\n\nand on cursive ... \n\n* [What is the origin of cursive characters?](_URL_4_)",
"I know this is late but I will add it anyway. The post by /u/shumpilumpa is the best here. The others that discuss Carolingian minuscule as the origin of lower case letters are interesting but not the right answer for this question. Carolingian minuscule is the origin for the specific letter forms that we use today, but have nothing to do with the origin of lowercase letters themselves.\n\nTo expand a bit, the earliest scripts did not really make a distinction between lower and upper case (called minuscule and majuscule), but as they were used more and more and for different purposes different letter forms began to be used for specific purposes. Monumental (epigraphic) scripts in general favored majuscule forms, what we call upper case today but perhaps better thought of as letter forms that are written between two lines, an upper line and a lower line, as in ABCDEF, etc. You can draw a horizontal line across the top of the letters and a horizontal line across the bottom of them. You can see an example on the wikipedia page on [Roman Square capitals]( _URL_1_).\n\nQuick, hasty writing, called “cursive” because it “ran” quickly across the page with few lifts of the pen off the page (or papyrus) is what we call minuscule or lower case, and was written between four lines. some letters, like aeuomn, etc. can be written between two horizontal lines like the majuscules, but many of them (like pqfdtyj) have ascenders and descenders, so that you can draw four lines, two on the top and two on the bottom. These scripts were used for informal writing, notes, comments, grocery lists, etc. You can see an example [here]( _URL_3_) from the first century AD, taken from the wikipedia page on [Roman cursive]( _URL_4_).\n\nBoth majuscule and minuscule scripts were used in the early middle ages. [Here]( _URL_2_) is an example of majuscule script from the Vatican Virgil, written in the 5th or 6th century. You can see in this example that there are no spaces between the words, something not really needed by native speakers who often read aloud. When non-Latin speakers like the Irish and the Anglo-Saxons were taught to read Latin, this cause some difficulty and so the Irish and English scribes began to introduce certain new practices that would help reading. One was spacing between words or at least groups of words. Another was a hierarchy of scripts, where the more formal scripts (majuscules) were used at the beginning of sections and then the less formal (minuscules) were used for the main part of the text. This distinction eventually was used for the beginning of sentences or of words, so that we capitalize the beginning of sentences and some nouns (in English). Today many people are omitting capitalization, but with the ease of reading computer fonts, we really don’t need that visual distinction as much anymore.\n\nAs for Carolingian minuscule, it was simply an attempt to standardize the many developments throughout Europe of Roman cursive minuscule. By the eighth century each different center of manuscript production had their own style of script (a few examples can be seen under the broad category of [Merovingian scripts](_URL_0_).), so that a scribe from ,for example, Luxeuil, would have difficulty reading the script of a scribe from Corbie, and vice versa. Charlemagne and the group of scholars he gathered wanted to standardize the handwriting throughout his empire so that everyone would write the same way.\n\nThis was somewhat successful, but it did not spread everywhere. It wasn’t until the late tenth century that a form of it was fully adopted in England and southern Italy used the Beneventan style script for centuries. By the twelfth century Carolingian minuscule had changed in various ways into what we now call under the umbrella term Gothic script, which became more and more diverse and varied until the humanists in the fifteenth century attempted to revert back to the ancient Roman script styles. By chance they mistook the Carolingian manuscripts as ancient and so Carolingian letter forms became the basis for the new Roman and Italic style of scripts (both given names suggesting the ancient Roman empire). The adoption of these new script styles coincided with the spread of printing so that many printed books used this style of font, as we still do today. You can see the similarity between Carolingian and early printed Roman font [here]( _URL_5_).\n"
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"http://upload.wikimedia.org/wikipedia/commons/c/c0/Evolution_of_minuscule.svg"
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[],
[
"https://drive.google.com/file/d/0B3bnIehMtOYtSWZZN0Y3NmFlazQ/view?usp=sharing"
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[
"http://www.reddit.com/r/AskHistorians/comments/1uxcxr/where_did_lower_case_letter_come_from_why_and_why/",
"http://www.reddit.com/r/AskHistorians/comments/2mto1g/how_did_latin_script_win_over_roman_cursive_in/",
"http://www.reddit.com/r/AskHistorians/comments/1rmcbr/where_do_capital_letters_come_from_what_was_their/",
"http://www.reddit.com/r/AskHistorians/comments/122yar/where_did_lower_case_letters_come_from_why_did/",
"http://www.reddit.com/r/AskHistorians/comments/1kgwvi/what_is_the_origin_of_cursive_characters/",
"http://www.reddit.com/r/linguistics/comments/1rmsqf/in_latin_script_why_do_lowercase_and_uppercase",
"http://www.reddit.com/r/AskHistorians/comments/2gcwdg/why_did_we_invent_capital_letters_when_did_they/"
],
[
"https://en.wikipedia.org/wiki/Merovingian_script",
"https://en.wikipedia.org/wiki/Roman_square_capitals",
"http://www.loc.gov/exhibits/vatican/images/vlib21.jpg",
"https://upload.wikimedia.org/wikipedia/commons/6/6f/I_littera_in_manuscripto.jpg",
"https://en.wikipedia.org/wiki/Roman_cursive",
"https://en.wikipedia.org/wiki/History_of_Western_typography#Classical_revival"
]
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||
becz2b
|
does strenuous physical activity cause your body to process caffeine faster?
|
If you drink a cup of coffee and work out for an hour, is there then less caffeine in your system than if you had just sat on the couch for an hour?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/becz2b/eli5_does_strenuous_physical_activity_cause_your/
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"There currently isn't enough research to say for sure.",
"A quick google search found a an in depth quora post on the subject.\n\nThe TL;DR being \"There seems to be little to no effect but it's still inconclusive\" \n\n\"Though there are plenty of studies of the effects of caffeine on metabolism and exercise, there are surprisingly few on the effect of exercise on the metabolism of caffeine. (Come on, Red Bull, cough up some research dollars.) What little has been done may have been prompted by the International Olympic Committee’s inclusion of caffeine in its list of regulated drugs and by concern over the effects of teens guzzling so-called energy drinks.\n\nAn unpublished 1981 study which looked at urine samples found little effect of exercise on time-dependent caffeine excretion , but since only small amounts of caffeine itself are eliminated via this route (caffeine is mostly metabolized in the liver to other stuff), the results may have been simply due to the noise inherent in the differences between small numbers.\n\nAnother study looked at blood plasma levels in subjects with and without exercise, but the study was small and limited to a few hours.\n\nOne of the few studies that would seem to speak to your question was conducted in France (European Journal of Clinical Pharmacology, March 1991, Volume 40, pp 279-282 ) using 12 subjects, half of whom were heavy coffee drinkers and half, light coffee drinkers, measuring serum caffeine levels. For both groups , exercise appeared to reduce the half-life (the time for the plasma caffeine concentration to come to half its original levels) from 3.99 hours to 2.29 hours. Perhaps not surprisingly, the levels peaked at higher values during the exercising part of the study. Also of interest: the heavy coffee drinkers eliminated their caffeine at a faster rate (a shorter half-life) than the light coffee drinkers.\n\nAlas, that may not settle the question (why is it never simple?). A 2002 study from the University of Guelph [Journal of Applied Physiology 2002, vol. 93, 1471-1478] which included measurements of both caffeine and its metabolites, while also noting higher plasma levels of caffeine in exercising subjects, found no statistically valid difference in the kinetics of elimination between the two trials. The authors speculate that the earlier study may not matched subjects well for physical fitness or controlled for cigarette smoking, dietary consumption of compounds known to alter caffeine metabolism, and (for the female subjects) menstrual status.\n\nThis lack of an effect was also noted in a study (British Journal of Clinical Pharmacology, 2008, vol. 65, pp 833-840) that looked at the pharmacokinetics of Ripped Fuel Extreme Cut, an energy drink containing (amongst other things) 21 mg synephrine and 304 mg caffeine. Synephrine is an alkaloid (as is caffeine) that is marketed both as a “natural” stimulant and as a drug (Oxedrine, Sympatol, and generics), and its use in energy drink is not without controversy, despite that it can derived from natural sources. Neither synephrine nor caffeine appeared to be eliminated faster during exercise, though whether there was a synergistic effect between the two drugs on the pharmacokinetics of elimination can’t be determined from the data. \n \nThere are a few other studies out there, but none that seem to enlighten us further. So what’s the bottom line? Given the ambiguity between studies, I’m apt to believe that if there is an effect on caffeine metabolism by exercise, it is not a large one. \"\n\nSource: _URL_0_ by John Kapecki\n\nSo we are left with 2 studies showing yes and 2 showing no. Like our friend John here I do believe there is likely some small effect, but it's just that, small.",
"No, the breakdown of caffeine is not controlled by your metabolism. Theres things in your metabolism that break down food called digestive enzymes. Enzymes make chemical reactions happen. The enzyme that breaks down caffeine is not a digestive enzyme, but is an enzyme called cytochrome P450 oxidase. Same with alcohol, but with a different enzyme (alcohol dehydrogenase)"
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3skwna
|
if objects give off a scent, and that scent is part of the object, why don't smelly objects just evaporate?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3skwna/eli5_if_objects_give_off_a_scent_and_that_scent/
|
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"The molecules that make up the scent are generally a tiny portion of the overall mass of the object. The object can lose its volatile scent molecules and still be left with a lot of stuff that doesn't go anywhere. "
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[
[]
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ze330
|
why is marriage equality an issue of state law rather than federal law?
|
Why is this up to each state? Doesn't that just split America apart?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/ze330/eli5_why_is_marriage_equality_an_issue_of_state/
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"The states have to *define* marriage within their state constitution before they may be able to regulate it. While marriage in North Carolina may only be strictly heterosexual and can only be done through a legal process, marriage in California also includes common law marriages, marriages that occur as a result of meeting certain rules like having children with someone. The reason that the federal government can't force gay marriage rights is because there isn't a definition that the federal government itself *has* for marriage, and you can't work with something that's undefined.\n\nThat being said, if there *was* a federal definition made, it would divide the United States *more* because it could make a huge number of people angry: instead of having one group angry in one state and just moving to a state they agree with more or just being angry with their state, a massive number of like-minded people across the entire nation get angry, and there isn't *anything at all* that would work as a quick fix except a change in the definition. Either the people being treated unequally will get extremely angry for being treated badly *nationally*, or those that disagree with gay marriage (for example, this doesn't just apply to gay marriage) would get angry because their religious freedom (marriages are often carried out within a church) would then be limited. Instead of having 100 different groups (the people for and against each individual local law in each state) there would be 2 very large, very powerful groups, causing much more damage.\n\nThe third reason is: local government problems. Marriage is defined within the state and also *taxed* by the state. Making marriage a federal issue would interfere with local tax systems. Marriages are also made official *in local courts*, **not** churches as what many people believe. Although you can be married within a church, it's documented and the court makes it official. Changing marriage laws federally would cause local court systems to lose power, *especially* with governing local issues with married couples.",
"It's a question of States' rights. Before the United States was founded, there were 13 independent colonies that shared no government except the British crown. During the American Revolution, the 13 colonies ratified The [Articles of Confederation](_URL_1_), forming a loosely bound national government. The union was weak; congress had the power to declare war, but not to form an army, instead having to rely on state militias. In 1789, the [Constitution](_URL_0_) was ratified by the states, strengthening the National Government. Under the Articles of Confederation, the State laws were the supreme law in each respective state. The Constitution was passed as the supreme law of the United States, that no State or Federal law can override.\n\nSo, under the Articles, the power of the governments went \n\n* State > Federal\n\nBut under the Constitution, it's redefined as\n\n* Constitution > State > Federal\n\nWhat it comes down to, is that the United States isn't just one big country, it's 50+ once independent States joined in a union. America's Strength comes from its ability to have different laws for different people in different States. Sorry if this didn't answer your question, but it's an important part of what you asked.",
"Each state is like a different playground. Every playground has people who like to play different kinds of tag in it. Some like freeze tag, others like tag that has safety zones, others prefer free for alls. \n\nIf all the playgrounds changed to just one type of tag, then many people would be upset. But if each playground was allowed to have their own version of tag, then people could go to whichever one they want.\n\nAlthough there can be some fighting over games of tag, there are things that many people agree on, like rules to basketball, baseball, and the very important capture the flag. This is what keeps the playgrounds together, not necessarily the issue of tag.\n\n\n\nOr weed.",
"*The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people.*\n\nThat's the 10th Amendment. Since the Constitution to the US does not explicitly define marriage, it is left to the states to decide.",
"States issue marraige licences. \n\n/thread"
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|
2wkocl
|
Speed of information?
|
I was reading recently about the speed of information and how person A who is 10 light seconds away from an explosion won't know about the explosion at the same time as person B who is 5 light seconds away, but 5 seconds after person B. Also, if the sun disappeared, how Earth would continue to rotate around the sun for about 8 minutes as if the sun were still there.
I understand information, which doesn't travel faster than light, taking 5 and 10 seconds to reach person A and person B, but does that mean that the event didn't happen until the information reached the observer? I ask this because how can the Earth continue to rotate around "where the sun was"?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2wkocl/speed_of_information/
|
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"Well, amongst other things, if the earth were to fly off immediately, then that would be \"information,\" wouldn't it? Because you could deduce the disappearance of the sun from it. So it won't happen that fast. ",
" > how can the Earth continue to rotate around \"where the sun was\"?\n\nThis is precisely why the idea of a [field](_URL_0_) is so central in relativistic physics. In this picture, everything is kept local: Earth never \"talks\" directly to the sun, but only to the gravitational field in its immediate vicinity, and the sun does likewise. When the sun vanishes in your scenario, the change takes eight minutes to propagate *in the field*. The gravitational field right around Earth doesn't know about the faraway event until then.\n\nHere's an imprecise analogy: picture a whirlpool made by spinning an object underwater. The spiral pattern comes out of the central point and moves gradually outwards. Now imagine that you stop spinning the object. The very outer edge of the spiral is still spinning, and it will take some time to \"realize\" that the object isn't spinning anymore.\n\n\nIt really wouldn't make any intuitive sense if the things acted just as if events were delayed by light-travel time! That's why fields were introduced. Later, we found out that we need them for other reasons too."
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[],
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1w0wb3
|
How can energy be quantized if both speed and wave length are both continuous quantities? How discrete is energy?
|
We all know that energy of electromagnetic radiation is equal to Planck's constant times the frequency. But both wave length and speed are continuous quantities that can take on any value, so how can it still be discrete?
Thanks!
|
askscience
|
http://www.reddit.com/r/askscience/comments/1w0wb3/how_can_energy_be_quantized_if_both_speed_and/
|
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"The range of energy of electromagnetic radiation is not discrete.\n\nEM radiation does come in discrete packets, though (photons).\n\nMaybe you were confusing these two things?\n"
]
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|
[] |
[] |
[
[]
] |
|
7qbgxo
|
Ages 1 to 4 are very important for brain development but yet most people can't recall anything from that time period. Why don't we remember our earliest memories?
|
I know the brain is rewiring a lot of neurological pathways to determine the most effective route, but what stops us from remembering our early years?
|
askscience
|
https://www.reddit.com/r/askscience/comments/7qbgxo/ages_1_to_4_are_very_important_for_brain/
|
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"It’s not that we forget our earliest years, it’s that we don’t form memories in the first place. The term for this is infantile “amnesia”, but this is not actually a form of amnesia — that would require forgetting. As infants grow into toddlers, their brains grow fantastically quickly. So much so, that any pathways that are deemed unimportant/weak are “pruned”. Pruning is the technical term actually. By age three, pruning calms down to the point where toddlers can start forming the memories they’ll remember for possibly the rest of their lives. However, usually the very earliest memories are traumatic or notable in some way. Pruning continues for some time into childhood. Maybe age 4. \n\nEdit: this has gotten more traction than I anticipated, and I have to clarify: when I say “we don’t form memories in the first place” what I’m saying is that we form memories that we will NOT be able to RECALL after our brains grow and pruning occurs. Toddlers can remember things, but, as we’ve all experienced, they forget an exceptional amount of their day-to-day experiences. As another user pointed out, toddlers actually are learning a metric ton of stuff (motor, language, etc.). \n\nEdit 2: another user pointed out that it is the delayed development of the hippocampus (learning/memory/encoding center) that contributes to infantile amnesia. ",
"Check out this article, it's essentially saying that the brain isn't really concerned about memories at that age, it just needs to get a grip on how reality works.\n\n_URL_2_\n\nThis article covers a much wider range of subjects including the gap in memory varies by up to 2 years depending on where you're born, the article says one theory on that is some cultures don't value early childhood memories and that may affect how hard we try to hold onto them. The article has no definitive answer but covers what appear to be reasonable theories such as the brain isn't \"recording\" episodic memories or *can't* record them yet due to a still-growing hippocampus.\n_URL_1_\n\nThis article is more focused on the explanation being proposed that the brain is still developing neurons in the region where memories are formed. \n_URL_3_\n\nI am absolutely not an expert in this field but I've read enough to know that memories are the connections between neurons in specific parts of the brain. There is also an element of flexibility, called [plasticity](_URL_0_), in the brain that defines how easily connections are made or broken. \n\nWhen we are very young the brain is very flexible, we have a lot to learn. Connections are made and broken quickly. \n\nIt would seem plausible that driving force for not being able to recall specific memories while the brain is still adding neurons to the memory-related parts of the brain(the bbc article mentions this) and while the brain is still extraordinarily flexible, those connections that make memories may not last very long. New neurons would disrupt those networks of connections and new memories could be making use of connections involved in other memories until there isn't enough left of a given episode's network to recall the memory. \n\nI wouldn't be surprised if culture played into that as well, if you try to hold onto a memory your attempt to access it can strengthen the connections to the episode over time and make it harder to forget(no idea if that affects accuracy of the memory). If no one in your culture gives a shit about a specific type of memory why bother trying to recall it? \n\nI know just enough about this stuff to get myself into trouble so check the sources and don't quote me on jack shit.",
"2 Memory systems are in place, subconscious instinctive learning, which is active even earlier than described, responsible for recognizing patterns much quicker than a cognitive approach, such as potentially dangerous situations or markers of danger, speech tones, etc. and is very resistant to change once a pattern is learned, which also has the potential to be problematic later in life when our mind is reacting in a non-beneficial manner. \"Unlocking the emotional brain: Eliminating symptoms at their roots using memory reconsolidation\" addresses much of the research surrounding this, as before 2007, research had largely concluded it was so difficult to change subconscious patterns once formed that the focus became cognitive behavioral therapy of trying to create entirely new pattern recognition on top of already learned responses.\n\nThe second memory storage is the conscious one, which is much more plastic and changeable. Memories are being recorded again at very early ages, but the issue with this system is that the catalogue and recall system hasn't developed until around 3 years, so there isn't a way to recall memories beyond that point.\n\nThe difference in these 2 systems can be very distinctly seen when memories of a traumatic event fade or are blocked from the mind, but the pattern recognition still causes anxiety when faced with a similar situation\n\nSubconscious pattern recognition is also much faster than cognitive thought, consisting of learned knowledge and truths, such as being able to recall that fire is hot and not to touch it or phobias, the event where we learned it doesn't need to be recalled for the situation to be assessed very quickly by instinct built over our lifetime",
"Finally something I can answer! Being a psychology minor I took Psychology of childhood and infancy last semester and was fascinated when I learned the answer to this question. This is commonly referred to as childhood amnesia and the reason this occurs has everything to do with both language and memory. In short children need to form memories to remember correct? But how do we form memories? By language! If you cannot understand the language fully yet than it is very difficult to develop long term memories. Children between the ages of 1-3 can form short term memories of course but not long term. For most people the language skills don't fully develop until ages 4-5 which is when you begin creating long term memories and why you can remember events from when you were 4 or 5 but not necessarily when you were 3 or younger. ",
"What you are taking about is autobiographical memory. Infants easily form other types of memories, including procedural memory (eg learning to walk), and semantic memory (learning what things are). Infantile amnesia is limited to autobiographical memories. There are lots of ideas as to why this is. One is a lack of self awareness - the child hasn't yet learned that they are an individual and that there are other individuals. The second is language development. Autobiographical memory is often descriptive, eg. \"I went to the store \". Encoding this memory may rely on language skills that have not yet developed. These are all related to the underlying neurophysiological development.",
"It depends what kind of memories you're talking about. Implicit memory stands in contrast to explicit memory and it is memory that is not consciously recalled (implicit memory is unconscious memory). These memories can begin even before birth (prenatal memory).\n\n",
"Pruning continues to go on throughout your life. For instance, you can probably remember what you had last night for supper, but do you recall what supper was a week ago from last Monday? Unless it was remarkable in some way, probably not.",
"There are a lot of things that you learn in your first few years. Most neuroscientists would call those 'memories.' What I think you're talking about is 'narrative recall.' That's when someone tells a story about what happened to them in the past: \"I was 4 and in the living room and the cat fell off the sofa, It was so scared that it ran right in to me. It was so traumatic! I'll remember it forever.\"\n\nNarrative recall requires a lot of acculturation. You need to have a concept of narrative and the narrative self as well as narrative composition skills. All of that cultural learning take a long time. You just don't have the psychological facility to lay down and rehearse self-narratives until you're a few years old. \n\nEDIT: typos. ",
"Infant brains are fairly undeveloped. In fact, newborn's sensory cortex isn't fully developed, so all of their senses blur together - music has color and a taste, for example - called synesthesia. Here's a fun read on it: _URL_0_",
"This might be tangential, but for those of us that do have some memories before the age of three, what causes this difference? (As far as I can tell, they weren't traumatic or impactful memories either; just a couple of specific moments.)",
"Infants form many memories such as learning how to crawl and walk and eat as well as emotional memories such as who is their favorite caretaker and what they look and sound like.\n\nThey do not fully form episodic memories because the hippocampus isn't fully formed until age 3.",
"I have a related question (hope this is allowed):\n\nWhat is the science on remembering feelings/emotions during this time? For example, I’ve read that relationships with parents are very important during this time, and emotional development is heavily influenced by events during this time even if they aren’t remembered (such as feelings of connection or love and on the flip side, threat or abandonment). Can anyone speak to the existence of that from a scientific perspective?",
"You shouldn't equate moments of critical development (underlying neural connections) with \"memorable\" moments. You seem to be thinking of **episodic memory**, which is likely a result of communication between networks in the hippocampus and cortex. These pathways might not be developed at a young age, and so you might not have distinct episodic memories. Nevertheless, important neuronal growth was occurring at the time.",
"This is very interesting. Are their studies by doctors on how best to capitalize on such a small scope of time? \nIs there some sort of stimulation that how’s best results for analytical problem solving and improving hand/eye coordination or sharpen reflexes?\n\nI don’t have children, but lots of my friends do and I’d love to help them out as new parents besides reading Hungry Hungry Caterpillar and making animal sounds to make them giggle.",
"I see pruning mentioned here and I'm not sure that's really the only reason why there's something like infantile amnesia. I think the development of language and formation of hippocampal structures and white matter tracts play a role. \n\nIn addition, there's a cognitive reason that people only remember things after a certain age. Another way to look at it is the development of the sense of self. If you understand memory formation (explicit memories that is), it is tied to various things like emotional valence, personal relevance, etc. This helps form autobiographical memories. One theory is that there's a shift in memory when a child develops a sense of self where there is a personalization of memories. \n\nsome references: \n_URL_0_\n\n_URL_1_\n\n_URL_2_\n\n\ndisclaimer; clinical neuropsychologist here.",
"An interesting related phenomena is called \"source amnesia\". As you've pointed out in your question, some people seem to recall very early childhood memories, for example how their infant mobiles looked like. As many different studies have shown (i.e. Julia Shaw's book \"the memory illusion\" is a good read on this) people may actually belief to remember things that other people have told them. When, for example, their parents told them stories about them as a toddler and they think about these multiple times when telling others, it might happen that they actually think they remember these facts from them being a baby and not from their parent's stories. \nOur memories are sometimes way more fallible than most of us think.",
"Memory requires having a frame of reference and context. \nIt's kind of like asking why there were no functioning apps on your conputer before you installed the system software. You can have all the peripherals hooked up for input and output... camera, keyboard, mouse monitors, speakers, but until that system software is written to memory, loaded, and up and running with the computer properly booted, none of that is going to be committed anywhere. You could even have a live internet connection, a home network, and a camera with a passthrough to the monitor to view the feed in real time, but until that system software is there, nothing is gonna save your video and upload it to youtube. The difference between the computer and us, is that we write our own system software, bit by bit, and build our own context ourselves with our nurturing and with hardware build by our genetics.",
"Interesting article suggesting how memories are remembered in narrative/storytelling cultures eg Maori and cultures with extended family structures eg Italy at younger ages compared to the norm.\n\n_URL_0_",
"During the ages 1 to 4, our brain has not yet developed fully, it is the age when the brain has to process lots of data like faces, voices, languages etc.. at that age if a language has to be learned by a child then it has to look for connections between different people and objects. Unlike now, we learn a language with translations and synonyms. I wouldn't say that the storage space is less but I'd say a developing brain wouldn't multitask. ( read and store at the same time )\n\nIt doesn't mean we don't remember anything from that age, emotional memories like pain can be recalled often.\n\nMemory is not actually you remembering an event. It's the recalling act in which you recall the \"last time\" you recalled that memory. ",
"I read once that our earliest memory is almost always a moment that makes us realize that we are an individual and have a separate consciousness, experience, and identity to others.\n\nApparently countries where children are generally respected as individuals, educated from a younger age, or given more independence have an earlier average “first memory” like 3-4 years old, but countries where kids start school later and dont have as much independence etc have earliest memories of more like 5-6.\n\nHaving lived in China for 8 years confirmed this to be the case based on my questioning of friends, students etc. ",
"Sorry I am so late to the party. I know Paul Frankland _URL_1_ has very neat leading hypotheses on this question. The hypothesis is that memories are formed during neurogenesis, and that the rate of neurogenesis governs the rate of forgetting - and thus produces infant amnesia. \n \nHe published a paper on this in Science a few years ago. \n_URL_0_ \n"
]
}
|
[] |
[] |
[
[],
[
"https://www.brainhq.com/brain-resources/brain-plasticity/what-is-brain-plasticityhttps://www.brainhq.com/brain-resources/brain-plasticity/what-is-brain-plasticity",
"http://www.bbc.com/future/story/20160726-the-mystery-of-why-you-cant-remember-being-a-baby",
"https://www.livescience.com/32963-why-dont-we-remember-being-babies.html",
"https://www.scientificamerican.com/article/why-can-t-you-remember-being-a-baby/"
],
[],
[],
[],
[],
[],
[],
[
"www.scientificamerican.com/article/infant-kandinskys/"
],
[],
[],
[],
[],
[],
[
"https://link.springer.com/chapter/10.1007/978-1-4615-9364-5_7",
"https://books.google.com/books?id=w1YrFypvmn8C&pg=PA67&lpg=PA67&dq=Development+of+Higher+Brain+Functions:+Birth+Through+Adolescence&source=bl&ots=J0mUh1YEFR&sig=R27kae-gbp0g_QEKSfOH13Ve34E&hl=en&sa=X&ved=0ahUKEwimye78pNjYAhVfHGMKHYB9CF4Q6AEIKDAA#v=onepage&q=Development%20of%20Higher%20Brain%20Functions%3A%20Birth%20Through%20Adolescence&f=false",
"https://www.researchgate.net/profile/Mary_Courage/publication/278857485_The_emergence_and_early_development_of_autobiographical_memory/links/55c9dda008aebc967dfa3c74.pdf"
],
[],
[],
[
"https://www.thecut.com/2016/07/italians-maori-and-divorce-kids-have-earliest-memory.html"
],
[],
[],
[
"http://science.sciencemag.org/content/344/6184/598",
"http://www.franklandlab.com/"
]
] |
|
qaujt
|
If a hospital/clinic is short on blood donors, why not draw blood from coma patients whose still-functioning systems can replenish the blood taken?
|
If the general public doesn't like to donate blood out of fear or laziness, why not draw blood from coma patients? Assuming a person could sign a form granting consent for such a procedure in case he/she ever did go into a coma, would this be a feasible plan? I mean, if it is, could we essentially design a system such that hospitals could continually produce enough healthy, extra blood to eliminate the need for 'traditional' donors?
|
askscience
|
http://www.reddit.com/r/askscience/comments/qaujt/if_a_hospitalclinic_is_short_on_blood_donors_why/
|
{
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"text": [
"I have the answer for you and it's *really simple*: Medical Ethics. That's the end of the entire discussion. It seems maybe silly, but really that is truly the answer.",
"There are a lot of problems with this idea, nevermind the major ethical problem that Mobilehypo mentions.\n\nFirst, what do mean by coma patients? Patients who are assumed to be in an irreversible coma from which they will never awaken? Well, certainly where I practice, there are thankfully not too many of those. Nationally in Australia, appproximately 27,000 donations a week are required to keep up stocks - there are not remotely that number of irreversibly comatose patients.\nIf its patients who are perhaps temporarily comatose or who are still receiving active treatment you have in mind, then taking a blood donation when they are critically ill may compromise their recovery.\n\nHowever, despite all that I agree with Mobilehypo - its the ethics that are insurmountable. Even if you could get a pre existing consent before the patient was comatose the idea of using people like battery hens to provide useful material is pretty distasteful"
]
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|
[] |
[] |
[
[],
[]
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|
3cbmjc
|
Can anyone help me identify some civil war era artifacts my grandmother gave me?
|
My grandmother the other day whipped out [this](_URL_8_) book she claims was written and printed in the civil war. I haven't removed the cloth to see the name of the book, but [here](_URL_2_), [here](_URL_3_) and [here](_URL_7_) are the first few pages. It's neat that she has a book that's so old, but I'd like to learn more about it (like who wrote it or how popular was it) and some of the things we found in the pages for her.
[These](_URL_6_) two bills were found in the book. One I can tell is a confederate ten dollar bill. The other uses Cyrillic characters, but I have no idea what it is. [Here](_URL_4_) is a picture of the backs to either confirm or dis-confirm their authenticity maybe.
I don't know what [this](_URL_11_) is, but I found it in there too. As far as I know it could be over a hundred years old or made yesterday. It looks like a tag for a shirt so I really am not expecting anything.
[This](_URL_9_) seems to be a map of a local river. I don't know how to read it or for what purpose it was used. Any information would be interesting! [Here](_URL_10_) is where the river is located in Tennessee.
Finally, on the back of the pages with pictures there were several handwritten notes. These are only a few, but there were several more.
[here](_URL_5_)
[here](_URL_1_)
[here](_URL_0_)
I can't read cursive, but if you can is there anything interesting there? I can make out some dates.
This may not be as interesting a find as I think. I was excited to see she had a book so old with old currencies in them and other cool things, so I wanted to find out more information. All she knows is her aunt gave it to her years ago and told her simply it was from the civil war. I have no plans to sell this and want to keep it for a long time, but are they worth anything? It makes little difference to me, but I would make an effort to preserve them better if they were rare.
edit: spelling
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/3cbmjc/can_anyone_help_me_identify_some_civil_war_era/
|
{
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"text": [
"I went ahead and had a go at the first of the handwritten notes. Some of it is pretty hard to read, especially the part in pink and the names. Here is what I could read. I've added question marks to indicate that I'm not sure about what it says \"(?)\", and where I can't read what it says \"?\". I've also left in the original spelling errors.\n\nJ.W., Thopson (?)\nJ.B., ?\nThis?\n\nI firmley believe by expirance\nas a gard at Libby Prison\nat Richmond va. That all \nThis Book contains is fact\nin regard to the treatment\nof Union prisners.\n\nLewis ?\nof ? of the 36 Va Regimental\narmy of the valley of va.\n\n"
]
}
|
[] |
[
"http://i.imgur.com/i3F3AwF.jpg",
"http://i.imgur.com/cfan4Ij.jpg",
"http://i.imgur.com/20bJDlZ.jpg",
"http://i.imgur.com/ugJrMLd.jpg",
"http://imgur.com/E1qZDZ4,20bJDlZ,ugJrMLd,MD1TiuY,uHpBZz7,j5st5UI,qq0bwpM,pdz4BMn,h6xUP5d,cfan4Ij,i3F3AwF#5",
"http://i.imgur.com/h6xUP5d.jpg",
"http://i.imgur.com/uHpBZz7.jpg",
"http://i.imgur.com/MD1TiuY.jpg",
"http://i.imgur.com/E1qZDZ4.jpg",
"http://i.imgur.com/pdz4BMn.jpg",
"http://www.higherpursuits.com/images/Duck%20River%20Watershed.jpg",
"http://i.imgur.com/qq0bwpM.jpg"
] |
[
[]
] |
|
3ayr2q
|
Why do many doctors prescribe prednisone for patients with infections?
|
I have on multiple occasions, from different doctors, been prescribed prednisone after going in for a checkup during a bad flu/cold. They state that it helps with the symptoms, which makes sense since it reduces inflammation.
However from what I understand, prednisone's antinflammatory effects are a result of it's suppressing the immune system. It seems incredibly irresponsible to me to prescribe an immunosuppressant to someone known/highly suspected to be infected by a pathogen. A google search revealed one case where [a 14 year old girl died as a result of influenza, after being put on a course of prednisone when she reported ordinary symptoms to her doctor.](_URL_0_). The news article does not indicate any suspicion of prednisone being involved, but it seems like a reasonable conclusion given that it would have reduced the immune response to the infection. Obviously most of the time people don't die from ordinary infections while receiving prednisone, but it certainly would have an impact on their ability to fight disease. With that in mind, it seems idiotic to casually dispense it in place of something like Ibuprofen.
Am I missing something here?
|
askscience
|
http://www.reddit.com/r/askscience/comments/3ayr2q/why_do_many_doctors_prescribe_prednisone_for/
|
{
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"text": [
"A well-functioning immune system often has undesirable by products when mounting an immune response. Additionally, the immune system is quite complex with numerous signaling pathways and different types of white blood cells responding. For example, the cascade of cytokines, which help propagate an immune response, also give you that \"I feel like shit\" feeling. Sometimes, the immune response is actually partially harmful.\n\nMany types of pneumonia, meningitis, or other widespread infections with big inflammatory responses show better outcomes when steroids are used. The idea, again, is that while the inflammatory response may be good at killing a pathogen, it may also be good at causing airway swelling along with it, for example.\n\n[Here is a study](_URL_0_) showing a list of different illnesses where steroids have been shown to help."
]
}
|
[] |
[
"http://www.citypages.com/news/carly-christenson-14-died-of-influenza-despite-receiving-flu-shot-6544638"
] |
[
[
"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1550829/"
]
] |
|
2xrwjv
|
What sources did Machiavelli use for his information on the military
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2xrwjv/what_sources_did_machiavelli_use_for_his/
|
{
"a_id": [
"cp39wlj"
],
"score": [
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"text": [
"From A Guide to the Study and Use of Military History\n By John E. Jessup, p66, on Art of War:\n\n'Machiavelli looked to the classics for inspiration and most of his ideas on training, tactics, organization, and command are little more than attempts to adapt practices described by Livy, Polybius and Vegetius to conditions prevailing in the fifteenth century.'\n\n\nThat being said, George Bull's introduction to The Prince suggests that it was his travels as a diplomat between 1498 and 1512 that reinforced his ideas concerning the use of citizen militias as opposed to unreliable mercenary bands. In this sense at least, some of his ideas could well have been based on his own experiences during the period.\n\n"
]
}
|
[] |
[] |
[
[]
] |
||
zhdz9
|
I need a research question concerning the concentration camps and the medical experiments performed by the nazis in them, can you guys help?
|
I have an assignment for History and I know I want to research the concentration camps and the medical experiments performed in them, but I can think of a specific question to research. Any help would be much appreciated.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/zhdz9/i_need_a_research_question_concerning_the/
|
{
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"c64lo4e",
"c64rkym"
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"score": [
2,
2
],
"text": [
"Are you thinking about the Mengele experiments? Or things like the reported use of taking Jews and turning their skins into lampshades and such?\n\nA few questions and avenues of research to go down. \n\n1. How widespread were experiments such as Mengele's? Things like that tend to get sensationalized, so maybe it's not as common as popular memory says. \n\n2. What kinds of specific experiments were done?\n\n3. Have we used any of the results of those experiments in modern science and medicine?\n\n4. How do his experiments compare to other human experiments? There's the obvious parallel with the Japanese Unit 731, but the US government hasn't exactly been forthcoming about medical experiments done on soldiers. I'm also thinking of things like smog experiments done on humans, that would never be countenanced today. \n\n5. How do those experiments show up in popular media? An obvious example is *Magneto's* background in the movie *X-Men: First Class*.",
"This book may be helpul. I read it over ten years ago, so I don't totally remember how much of it is on point.\n\n_URL_0_\n"
]
}
|
[] |
[] |
[
[],
[
"http://www.amazon.com/The-Nazi-Doctors-Psychology-Genocide/dp/0465049052"
]
] |
|
2s6ala
|
Why can gravitational lensing result in both Einstein Crosses and Einstein Rings despite gravity being a symmetrical force?
|
Me and a colleague were looking at [this](_URL_1_) earlier, and it struck us as odd.
We have been familiar with [Einstein's Rings](_URL_0_) for many years, and this does not seem problematic to either of us as the symmetrical nature of gravity around the massive object causing the lensing would result in the gravitationally warped light making a ring from our perspective. But when we look at the Einstein's Cross, we can't help but wonder why is that image not smeared similar to the ring?
*Also, sorry for posting the same question again, it got buried last time and I am very curious.
|
askscience
|
http://www.reddit.com/r/askscience/comments/2s6ala/why_can_gravitational_lensing_result_in_both/
|
{
"a_id": [
"cnmm2bl",
"cnmm931",
"cnmoin4"
],
"score": [
48,
260,
10
],
"text": [
"To get a nice Einstein Ring, you need to have the telescope, one singular lensing point, and the target arranged in a perfect line. If the telescope is slightly off the focal line of the lensing, then you will see only an arc of the full ring. \n\nAnd if you have more than a singular lensing point, like if you're looking past a cluster of many massive galaxies rather than a single galaxy, then each galaxy has its own focal line in a slightly different direction. So your telescope will be looking slightly off the focal lines of a number of different lenses, and you will see multiple arcs of the target, which sum together into multiple distorted images of the target.\n\nThis phenomenon is known as *monocular polyopia* (multiple images seen through a single lens). A much closer-to-home occurrence of this phenomenon is the \"ghosting\" images seen by people who have the eye condition [keratoconus](_URL_0_). ",
"It depends on the projected mass distribution of the lensing object.\n\nIf everything is aligned perfectly, and you have a spherically symmetric mass distribution in the lensing object, you get an Einstein Ring.\n\nIf instead of a spherically symmetric lens, you have an ellipsoid symmetry, you get the Einstein cross. The four objects will indicate the major and minor axes of the lens' mass distribution.",
"You've gotten good answers already, so I'll just add that a gravitational lens doesn't behave the same as an optical lens, and that's why we see so many arcs and duplicated images in those famous Hubble pictures. The Wiki article covers it well: _URL_0_"
]
}
|
[] |
[
"http://en.wikipedia.org/wiki/Einstein_ring",
"http://en.wikipedia.org/wiki/Einstein_Cross"
] |
[
[
"http://en.wikipedia.org/wiki/Keratoconus#Signs_and_symptoms"
],
[],
[
"https://en.wikipedia.org/wiki/Gravitational_lensing"
]
] |
|
95e6pq
|
what does it mean that a company goes private or public.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/95e6pq/eli5_what_does_it_mean_that_a_company_goes/
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"For profit firms are always owned by someone.\n\nMost are privately held, meaning they are owned by individuals or small groups of people who manage them as they see fit.\n\nFirms can also go public, selling shares of ownership to anyone who wants to buy them. This can, for valuable firms, raise a ton of money for the firm and make the former private owners huge amounts of money. However, public firms must also issue regular financial reports to investors and generally be beholden to investors' interests.\n\nMusk absolutely hates this, and would love to buy back stock in his firm and allow him to manage it how he likes.",
"A private company is wholly owned by some number of private entities. These companies don't have to present earnings, nor do they have to work specifically to earn shareholders money (meaning they are more free to make certain decisions). You can't go out and buy stock for private companies - they're wholly owned. Examples of large private companies include Cargill and Aldi.\n\nA public company, on the other hand, has opened themselves to the public for ownership. Any company listed on a stock market is public, and you can go buy some portion of it right now. They must meet certain requirements to remain listed - like earnings reports and working to earn shareholders money. Microsoft, Oracle, and Google are all public companies.",
"It means whether they have public shareholders or not, ie. can any investor buy shares of stock in that company. \n\nGoing public and selling shares to investors is a way to gain money for expansion and a way for founders to gain liquid assets — turn ownership into cash they can spend.\n\nBut being public also comes with all sorts of reporting requirements such as quarterly earnings releases. And can often mean company execs are pressured to act in ways that will boost stock now vs. what is best interest longer term.\n\nWhat Elon Musk is proposing is to buy back all the shares of Tesla, currently a publicly traded company, so that it is again owned by just him and a small number of investors such that they don’t have to disclose financial information. And they would all the profits or growth in company value."
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zeb4o
|
What are the evolutionary benefits to being bipedal and having our knees face the way they do? Reversed knees seem more practical.
|
I was watching a typical documentary on wildlife and observed an ostrich running. The way their legs are allows for more "spring to their step", which allows them to run much faster. What purpose does being bipedal serve? Is there an evolutionary benefit for our knees to face the way they do?
|
askscience
|
http://www.reddit.com/r/askscience/comments/zeb4o/what_are_the_evolutionary_benefits_to_being/
|
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"Knees face the same way on almost every species of animal. If you look at an ostrich's skeleton, you will see that it has an incredibly short femur which is hidden under it's feathers. What appears to be it's shin is the equivalent of our foot, and that it walks on its toes. Horses are the same way, along with any animal that appears to have \"backwards knees\".\n\n[Skeleton](_URL_0_)",
"This is a common misconception. Many animals have feet that are significantly longer (proportionally) than a human foot. What you're thinking is a backwards bent knee is actually an ankle. The shin and thigh are higher up on the leg, but they're there and bent the right way. What you're seeing as the 'foot' at the end is actually just the 'fingers' (claws). Everything in-between the ankle and claws/fingers is a very long 'arch'.",
"Evolution is not forward-thinking, it simply modifies existing structure. So if our quadrupedal ancestors had forward-bending knees, then that's what we inherit. There is no plausible evolutionary path for knees to suddenly become backwards-facing.\n\nThere are some spectacular examples of evolutionary leftovers. For example, why do you have appendix? why do males have nipples? One of my favorite examples is [laryngeal nerve](_URL_0_). And, to borrow a quote from Neil DeGrasse Tyson, what is going on between our legs? We have the entertainment complex right next to the sewage system. No engineer would ever design that.",
"While Nilhaus is correct about knees, more explanation is needed.\n\nI'm not an expert in the area but one evolutionary reason for the elongated femur and \"flat-on-the-ground foot\" aka plantigrade posture appears to be increased load bearing capability and stability. With this morphology, the leg becomes more like a strong vertical column with a stable, wider base with more structure.\n\nHumans and other primates likely developed this as standing, carrying larger loads, and walking LONG distances became more important. Other heavy animals have developed a similar leg morphology - look at the [Elephant knee](_URL_2_) and the [Apatosaurus knee](_URL_0_) for example.\n\n[This article](_URL_1_) has a good summation: \"Relative to other mammals, humans\nare economical walkers, but not economical runners. Given the great distances hunter-gatherers travel, it is not surprising that\nhumans retained a foot posture, inherited from our more arboreal great ape ancestors, that facilitates economical walking.\"",
"I know the reason! \n\nHumans have the ability to lock their knees such that they can stand for a long time without fatiguing their quadriceps (thigh) muscles. Quadrapeds cannot do this, but then again, they dont have to since four legs gives stability anyway. Advantages in terms of evolution is of course far less energy expenditure in standing, and ability to use hands for carrying meat, using tools, gesturing and non-verbal communication and having binocular vision and standing tall from the ground to detect predators hiding in the shrubs etc.\n\n"
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"http://jeb.biologists.org/content/213/5/790.full.pdf",
"http://www.madsci.org/posts/archives/2003-05/1053313506.Zo.r.html"
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62dqxr
|
why are kiwi fruits and peaches hairy?
|
What's the function of the hair on the skin of these fruits?
EDIT: Thanks to all you guys reminding me that I like kiwi's by constantly commenting, I have eaten 4 of them today!
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/62dqxr/eli5_why_are_kiwi_fruits_and_peaches_hairy/
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"Quite simply, nobody knows for sure. Some scientists have speculated that it's to deter bugs.\n\nIf you believe in evolution, then you also should recognize two things: Evolution is a process and not a product (so just looking at the end result tells you nothing about how or why something came to be), and that evolution doesn't actively move toward a better solution, so random mutations can survive that do nothing to help or hinder an organism.\n\n(If you don't believe in evolution, then there's some design plan for kiwis and peaches.)",
"To keep small bugs away -- it's hard for them to walk on the skin and get close to the fruit to bite into it -- and also the hairs add surface area to control moisture in the fruit. [Kiwi-specific info here](_URL_0_).",
"With peaches specifically, they are hairy because their human farmers preferred that. Peaches have been a domestic fruit for over 6,000 years (per [Wikipedia's Peach article](_URL_0_)) and have a recessive gene that causes loss of the hair (sold as nectarines). \n\nIf farmers didn't prefer the hair (it helps protect the fruit from bruising) they would have selected the hairless cultivars a long time ago.",
"Hair in plants can be used for defense but also to prevent water loss. The hair created a \"boundary layer\" that keeps the air slightly more stationary so when the water tries to evaporate, the air immediately around the plant is already fairly saturated with water. ",
"because they dont shave! Ha ha! No its an evolutionary method a. to prevent bugs from walking on them as eaisly and b. its eaiser to control moisture loss with little hairs that can control the temp of the fruit.\n",
"Mainly for water retention. Keeps em nice an moist inside.\n\nAlso helps deter pests because they have the appearance of being less edible.",
"In humid environments where pests such a bugs can be an issue for fruit, some have developed this \"hair\" to keep the bodies of insects off the surface of the fruit, as it is irritating to them, and it will also make it difficult to lay eggs, because they cannot penetrate the hair to reach the skin of the fruit. ",
"A buddy of mine is a paleo-botanist.\n\nHis take is that, in general, when the question is, \"Why do plants < x > ?\", where < x > is something that doesn't obviously benefit the plant (like get you high, itch, have hair etc), the answer is usually pest control.",
"Was going to ask what kinda weird ass peaches you buy, but decided to google it and they are indeed hairy, but I've never seen a hairy one in a store. Oddly enough, kiwis in stores are hairy.",
"In some plants in dry places, to compensate for the lack of moisture in the area, instead of leaves, some plants will develop little hairs instead, this increases surface area on the plant and allows for more pores on the plant to absorb water, while not absorbing too much light as leaves would.",
"Follow up question: is it really \"hair\" the way that animals produce it or is it a different compound?",
"\"Well for two reasons. First, to keep bugs away. The little hairs annoy the bugs and help to keep the plant bug free. Kind of like those spikes they put on the window air-conditioning units to keep birds from nesting/hanging out there. Nobody wants bird poop in their air conditioner!\n\nSecond reason is to help the fruit retain moisture. The hairs do this in two ways. They collect the dew in the morning so that helps keep the fruit moist. And, they act like a barrier, keeping the moist air close to the fruit. Think of the hairs like a little shirt for the kiwi. Your shirt keeps warm air close to your body and the hairs keep the moist air close to the fruit. Cool huh?\"\n\n[Sauce](_URL_0_)",
"Well, not all peaches are hairy...Peaches that lack a particular hairiness gene are called \"nectarines\". ",
"The kiwis you buy at the store are still hairy because they remove the heads and legs but they don't pluck them.",
"Anyone else read this as 2 questions first and get super confused?",
"ELI5: Why is Kiwi a weird fruit, a weird bird, and what New Zealanders are called? ",
"I was going to complement you on using the correct name \"kiwifruit\". But then you ruined it with your edit (and a bonus greengrocers apostrophe). ",
"Followup question: chemically, are fruit and bug hairs the same as ours?",
"Did you know there are kiwifruit without hair that grow in cold climates? Look up hardy kiwi.",
"As a New Zealander, reading this thread, the whole bit about rubbing kiwis on bare legs is entertaining haha ",
"Because sometimes you've got to make it through a little hair to get to the sweet juicy inside."
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3pw9ji
|
how can imprimis pharmaceuticals get a drug on the market so fast and for a such low price?
|
How can Imprimis Pharmaceuticals get a drug on the market so fast and for a such low price? I've always tought that the process of new drugs is very hard and a legislative hell, so I'm wondering how it is possible for a company to do this so fast? Or is it just a case of the drug already being approved?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3pw9ji/eli5how_can_imprimis_pharmaceuticals_get_a_drug/
|
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"This is not a new drug. Both of the ingredients have already been approved individually.\n\nUsually you would need to get FDA approval even for doing this, which is much less expensive than a full new drug application, but still pretty expensive and time-consuming.\n\nBut in this case Imprimis is using a loophole by calling itself a ['compounding pharmacy'] (_URL_0_) rather than a drug company."
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43fycy
|
what does "my asthma is acting up" really mean?
|
What exactly does it mean when someone says, "My asthma is acting up again?" How does a condition act up and what triggers it? Also, how does someone "grow out of their asthma?"
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/43fycy/eli5_what_does_my_asthma_is_acting_up_really_mean/
|
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"As an asthma sufferer, I tend to use the phrase to mean I'm a bit more wheezy than normal and more likely to suffer an attack.\nMost suffers have certain triggers, personally I know that if it's really cold outside, going from a warm building to the cold will normally bring on at attack so I have to up my medication. Same of I have a cold as they tend to sit straight on my chest and linger for a while as my lungs aren't as strong. Other people suffer with pollen, dust, food sources. It's all about knowing your trigger.\nDepending on your trigger, it is possible to grow out of it as you may become stronger/increase your immune system as you get older so your lungs become stronger and better able to fight off the affects. My daughter for example, suffers with asthma but only when she has a bad cold or when her immune system is low. We are pretty confident she will grow out of it as she becomes older and more able to fight off infections etc.",
"People do grow out of their asthma. People are still unsure exactly why, but one idea is that as you get older, your airways get wider. And that's all asthma is - a narrowing of the airways making it hard to breathe. \n\nThere's a lot of things that cause it. Doing things that tire you out like exercise, cold air, pollution. It can be because irritants get in your lungs, or something triggers your body to defend itself when it doesn't really need to (we call this allergies). This makes your air passages tighten and grow small, like clenching a fist. And that makes it harder for air to get in and out, which you need to live.\n\nThat's why it's important for people with asthma to carry their medicine, which they puff in to their lungs. This tells the lungs to relax, making the airways wider.",
"Asthmatic here. A simple explanation for asthma is a condition in which the airway to the lungs narrows and becomes clogged with a mucus that, if not treated, may completely close the airway and prevent the individual from breathing. Why does the mucus appear, you ask? Everybody's body can produce this mucus, and can do so if the lung becomes infected or the body thinks something is trying to attack the lungs. The mucus acts as a barrier to prevent further damage. However, with asthmatics, the lungs tend to glitch out and occasionally think that they're being attacked when actually, the asthmatic may just be exercising or whatnot. Because the lungs think something's wrong, this mucus will occur and cause the individual some discomfort, or as we say \"my asthma is acting up.\"\n\nWhen you hear someone say \"my asthma is acting up,\" they're probably referring to wheeziness, pressure on the chest, coughing, lung pain, or a shortness of breath. \n\nEverybody's asthma is triggered differently, but primary culprits are exercise, pollen, smog, stress, change in temperature, extreme temperatures, dry/humid weather, and so many more. What triggers one asthmatic's asthma to act up could not affect another asthmatic at all, so it really depends. \n\nOccasionally, people grow out of their asthma. This is usually the case in teenagers who had asthma in their childhood. Along with all the other changes that happen to their body during puberty, the asthma \"glitch\" can simply fade away."
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ezenvy
|
I'm a regular, married, male, 30 year old office worker in 1901. What do I actually do in the evenings?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/ezenvy/im_a_regular_married_male_30_year_old_office/
|
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"This is both a specific question, but also a fairly broad one, of course, so I would preface by saying that I'm only talking about a very narrow slice of what might be available to you as a married man, comfortably middle-class, in Somewhere-ville, USA. The assumption I'm principally making is that you are a fraternal man, that is to say, a member of a male social club!\n\nFrom the late 19th century through the early 20th, so smack dab on the point in time of which you speak, being a member of a Men's fraternal organization was quite common, and a sign of middle-class respectability, leading to its label as the \"Golden Age of Fraternity\". Some groups still remain today in fact, although the institution suffered a long decline beginning in the mid-20th century, and include names you might recognize like the Elk's Club, or the Knights of Columbus. The tradition of course dates back further, including more storied groups such as the Odd Fellows and the Freemasons, but the heyday of it in America was centered on the turn of the century.\n\nThere was no set model which these groups might follow. Some, such as the Rotarians, were set up to be more centered on giving back to the community. Others, such as the Elk's, were founded to be social clubs All of them were for men only, although often a women's auxiliary would exist, and many were restricted further by race or religion, the most common restrictions being to white Protestants. This of course was the impetus for the creation of other groups, such as the Knights of Columbus, which was created as a mutual benefit society for Catholics, especially those who were recent immigrants.\n\nTo get to the heart of the question, these groups existed in several capacities. They had the mumbo-jumo rituals that you often associate with groups like the Masons, often created in direct emulation of those older groups, and members would earn various titles and progress through the ranks in importance. As noted, some might encourage service by their members, others might provide support to their community, a group safety net for all members, or even death benefits for their family, but for our focus here, the socialization can't be ignored! \n\nWriting a bit later (1922) than your chosen date, to be sure, Sinclair Lewis nevertheless, provides an excellent satire of club life for the middle-class American male in his novel *Babbitt*, writing:\n\n > Of a decent man in Zenith it was required that he should belong to one, preferably two or three, of the innumerous “lodges” and prosperity-boosting lunch-clubs; to the Rotarians, the Kiwanis, or the Boosters; to the Oddfellows, Moose, Masons, Red Men, Woodmen, Owls, Eagles, Maccabees, Knights of Pythias, Knights of Columbus, and other secret orders characterized by a high degree of heartiness, sound morals, and reverence for the Constitution. There were four reasons for joining these orders: It was the thing to do. It was good for business, since lodge-brothers frequently became customers. It gave to Americans unable to become Geheimrate or Commendatori such unctuous honorifics as High Worthy Recording Scribe and Grand Hoogow to add to the commonplace distinctions of Colonel, Judge, and Professor. And it permitted the swaddled American husband to stay away from home for one evening a week. The lodge was his piazza, his pavement cafe. He could shoot pool and talk man-talk and be obscene and valiant.\n\nLewis is tweaking the nose of the concept here, but there is also a marked grain of truth, too. Membership in these organizations \"represented one of many vehicles for participation in social and political life\", to quote Clawson. They provided the social respectability that in the novel George F. Babbitt, the stand-in for a typical white, middle-class American, craves. They provided social connections and business connections which could, in theory, help one advance in life. Many also provided places for entertainment and leisure, and food service was quite common too. So you, as a 30 year old office worker, at least once a week, are undoubtedly going to *not* go home for the evening and spend it with your wife and child, but rather are going to head to the Club. \n\nMaybe you are a Booster, like Babbitt was oh-so-proud of, or maybe you are lucky enough to have the right friends and connections, and can spend your evening at the Masonic Lodge. Sometimes, of course, there will be ritual mumbo-jumbo to go through, or on other times, there might be a meeting where some members will be giving speeches. Other times thouh, it might just be you and a few other respectable gentlemen of the town spending an evening together. Perhaps you play bridge, or maybe you discuss the upcoming elections. If you are feeling a bit more solitary, there is probably a nice armchair you can go read the paper in. Dinner will possibly be served, depending on the club. If you are a regular on a specific night, there probably also others who are regulars on that night as well, so there is probably a specific level of camaraderie between you and those fellows, beyond simply your fraternal brotherhood.\n\nAs, presumably, a mid-level office worker, business connections are quite important for you as well. Likely other men from your work are members, so you might be discussing business there. Woe be the office worker who *isn't* there, as it might mean their career is going to stagnate! Maybe your boss is a member too, depending on the specific class construction of the club, and this offers a place where you can interact with him as an *equal* rather than an underling! Depending on your business, you might also be able to help your business! Brothers patronize each other, after all. \n\nDo you work in insurance? Grand! Many of your brothers are going to be coming to *you* as their broker, just like you of course will go to the doctor who is a member when you are sick, and patronize the grocer who proudly calls himself a your brother as well. But these connections don't come free. They are benefits that *come* from the social aspect of the Club. A dues-paying member who never shows his face isn't going to have the same level of trust as one who is front and center at every event, and makes friends with everyone. Are you gunning for that promotion? If you have the most sales this year, will you get a nice raise? One evening a week *definitely* isn't enough! You probably should be going to the club three days a week perhaps? And make sure to alternate which ones! And that doesn't even include the weekends! \n\nHeck, maybe it would be best to join several clubs! *Babbitt* is satire, but the protagonist certainly isn't *unusual* in being a member of more than one such group. To take one admittedly extreme example, Joseph Cullen Root founded the *Modern Woodmen of America*, and the *Woodmen of the World* after the first group kicked him out, but before that, had joined the Knights of Pythias, the United Workmen, the Odd Fellows, the Masons, founded the Iowa Legion of Honor, *and* previously been in the VAS Society, which kicked him out too. HE might be a bit excessive, but it was hardly unusual. In a study conducted by Connecticut in 1891, it was estimated that adding all the membership of all the clubs \"*would be in excess of the total male adult population of the state.*”\n\nGetting in to these groups varied greatly. Some openly recruited, but this was a sign that it was not particularly prestigious. Others might be a bit less vocal, while the best Fraternal groups, like the Masons, were more of a \"don't ask us, we'll ask you\" kind of deal, which of course was something that you might reach by climbing the ladder. Start as a member of a lower group, and prove yourself to slowly get invited to better and better ones! \n\nI would reiterate again the assumptions being made here, which more than anything is that you are *white*. Black exclusion from Fraternal organizations was by far the norm, but in response, many African-American men founded their own groups, which provided similar social function, as well as the economic benefits. Many would take on names in emulation of the white groups, such as the black Elks Club, which not so subtly tumbed their nose with the addition name of *Improved Benevolent and Protective Order of Elks*, compared to the white's only group which, as *Benevolent and Protective Order of Elks*, they were clearly an improvement on!\n\nFrom WWI on, competing sources of entertainment outside the house would start to erode the Fraternal Clubs, such as an official of the Mooses noting in the 1920s how:\n\n > [T]he radio, the automobile, the jazz band, the outdoor entertainment, the fast means of travel [have placed] the old style lodge meeting, in which the same ceremonies, week after week, and month after month, are carried on, somewhat in discard.\n\nAnd in the post-WWII period, that slide only continued further, for which I would simply direct to /u/yodatsracist in [this comment](_URL_0_), but to return to the beginning, you, as a respectable married man of 1901, would be in their Golden Age. You would be spending at least one evening out there with your Fraternal Brothers, socializing and feeling important. What you do those *other nights* at home though, I will leave to someone else to weigh in on!\n\n**Sources**\n\nBeito, David T. *From Mutual Aid to the Welfare State Fraternal Societies and Social Services, 1890-1967* Chapel Hill: University of North Carolina Press, 2000.\n\nClawson, Mary Ann. *Constructing Brotherhood: Class, Gender, and Fraternalism*. Princeton University Press, 1989.\n\nLewis, Sinclair. *Babbitt.* United Kingdom: Grosset & Dunlap, 1922."
]
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[] |
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||
71rze5
|
how do common objects like remotes detect when their batteries have low power?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/71rze5/eli5_how_do_common_objects_like_remotes_detect/
|
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"Batteries drop in voltage as they drain, and when they're \"dead\" that simply means they don't provide enough voltage to run the device. They still have some charge to them.\n\nAnyway... a voltage meter within the circuit can measure this, and reports battery life based on it. ",
"Most battery powered things don't actually use the power 'directly' from the battery, but put it into a capacitor first, which is like a bucket for power. A clever device keeps track of how quickly and *forcefully* the bucket gets refilled when it empties, and has a wall chart of what to expect. If the bucket starts filling way slower or more gently than the wall chart says, the clever device sends a bit of power down a special 'battery is low' cable, which will probably have a light on the other end of it."
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[] |
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[],
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||
6dgeth
|
genetically speaking who is closer to my father, myself or his brother?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6dgeth/eli5_genetically_speaking_who_is_closer_to_my/
|
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"text": [
"This is a very interesting question, and one that often comes up when considering organ transplantation.\n\nYou can think of your genetic makeup as coming from your mother and father equally (50% each). This is because, of the two sets of chromosomes in each of your cells, one set must have come from each of your parents.\n\nNow lets consider siblings.\n\nBoth your father and his brother also received 1 chromosome set from each of their parents. This means that there is a spectrum of genetic similarity that can exist between the two, because they get their genes from the same pool of possible genes (ie your paternal grandparents genes). In turn, they can range from being very similar, to being not similar at all. On average though, they will be around 50% similar, just due to probability. \n\nThis is why organ donation from a sibling can lead to much better outcomes, and a lower rejection rate, because there is a chance that their compatibility is greater than the unchanging 50% similarity you get with your own child. \n\nHope that helps. Source: Medical Student",
"We have two types of genes: the ones in our chromosomes and the ones in our mitochondria. You get half of your chromosomal genes from your mother and half from your father. On average, you share about half of your chromosomes with first order relations (brothers, sisters, mother, father, your own sons and daughters, etc).\n\nYour mitochondria only come from your mother. The egg cell that was fertilized by your father's sperm had mitochondria. The sperm did not. You received all of your mitochondrial DNA from your mother. \n\nYour father and his brother share the same mitochondrial DNA. You have your mother's mitochondrial DNA\n\nThat means your father is genetically a bit closer to his brother than to you."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1y7eub
|
What is the history of, and design conventions (if any), of album art?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1y7eub/what_is_the_history_of_and_design_conventions_if/
|
{
"a_id": [
"cfi10d4"
],
"score": [
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"text": [
"If by album art you mean like for music CD's (or LP's and EP's back in the day), the history and design conventions are pretty broad. Some producers hire graphics artists or designers for their album covers, some artists make their own or have artistic friends make them. I'm not quite sure of the history in terms of when it began or what the first was, but I can point out a couple interesting design conventions from an art history standpoint!\n\nFranz Ferdinand. This indie Rock band has nearly all of their album designs based off of Soviet Constructivism:\n\n[album](_URL_0_) [painting](_URL_6_)\n\n[album](_URL_3_) [painting](_URL_2_)\n\nColdplay: more mix in design, but [Viva la Vida](_URL_4_) features [Liberty Leading the People](_URL_1_)\n\nThe Beatles: Their famous [Abbey Road](_URL_5_) cover was thought up by McCartney and professionally done. The photograph is not just a cover anymore, but part of British modern photography."
]
}
|
[] |
[] |
[
[
"http://bigotherbigother.files.wordpress.com/2010/09/franz_ferdinand_-_this_fffire.jpg",
"http://upload.wikimedia.org/wikipedia/commons/a/a7/Eug%C3%A8ne_Delacroix_-_La_libert%C3%A9_guidant_le_peuple.jpg",
"http://arttattler.com/Images/Europe/Netherlands/Amsterdam/FOAM/Alexander%20Rodchenko/Lily-Brik-Poster.jpg",
"http://www.musiclipse.com/wp-content/uploads/2013/05/You-Could-Have-It-So-Much-Better-franz-ferdinand-cover-album1.jpg",
"http://www.cluas.com/indie-music/Portals/0/Blog/Files/5/692/coldplay.jpg",
"http://fstoppers.com/wp-content/uploads/2012/01/lglp0597%2Babbey-road-album-cover-the-beatles-poster.jpg",
"http://uploads4.wikipaintings.org/images/el-lissitzky/beat-the-whites-with-the-red-wedge-1920.jpg"
]
] |
||
558miu
|
scary clown sightings
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/558miu/eli5_scary_clown_sightings/
|
{
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"d88gil3",
"d88gtcy",
"d88gx2d"
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2,
2
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"text": [
"At this time, there really isn't a set answer. I personally think that there was one crazy person who did it and got on the news so a bunch of other crazy people hopped on the bandwagon. Also a day or two ago a high schooler was stabbed like 6 times by one of the clowns so be careful. \n\nHere's a great video about the clowns: \n_URL_0_",
"There have been several reported sightings of scary clowns or scary clowns making threats on social media in several states. In some cases, people report seeing a clown and being scared, but nothing else. In other cases, people report that the clowns had weapons or were trying to lure kids away. And in some cases people dressed as clowns and released threatening videos or statements on social media.\n\nIt's unclear what the connection is between the cases. Gags was a clown that people reported seeing around Green Bay and someone even made a Facebook page for him. The creator of the page recently revealed that Gags was part of viral marketing for an upcoming independent horror film. So some of the sightings may be viral marketing, but it's unlikely that the clowns with weapons or threatening videos are viral marketing.\n\nFor the vast majority of reports, police never found a clown. That could mean that the clowns move away quickly, but it could also mean that people are perpetuating a hoax and making fake reports. If the clowns really were there, then they might be doing it as part of viral marketing, they might be copycats, or there might be some coordinated pranksters doing it for the lulz. If the reports are fake, it could be viral markets making the fake reports, or copycats, or coordinated pranksters.\n\nIn at least a couple of cases, police saw a clown, so there are clearly at least one or two people trying to make the hoax a reality. \n\nWe know two things for sure: the first clown sightings in Green Bay were viral marketing and police have not been able to confirm most of the subsequent reports. To me, that means it's likely that the whole thing started as viral marketing and then it spawned copycats or a group of pranksters picked up on it and decided to make it a national thing (or there are some coordinated pranksters and some independent copycats).",
"They are copycats perpetuated by the news coverage of the event. \n\nThink about it this way. You're bored and want some lulz. The news media, fueled by people's superstitions, makes an actual news piece out of people dressing up like a clown at night. *Because* they made a news story about it, that means that *other* news channels will do their *own* piece about it. \n\nSo for the cost of a clown suit and a night standing in the dark, *you* can become a viral news story and have great lulz. You can go to work and listen to your coworkers talk about clown invasions or ghosts or demons and lulz to yourself, knowing that it was just you, all along. \n\nBy giving things attention, the media all but ensures their repetition. It isn't like people never did this before. There are hudnreds of prank videos online of people going out and scaring people dressed as clowns or Jason Voorhees or any number of characters well before this became a \"news sensation\". \n\n "
]
}
|
[] |
[] |
[
[
"https://youtu.be/FC5IIbbPE8w"
],
[],
[]
] |
||
c26r4t
|
How do we know what texture the skin of an extinct animal was? Like dinosaurs, how do we know that they didn't have like fur or something?
|
[deleted]
|
askscience
|
https://www.reddit.com/r/askscience/comments/c26r4t/how_do_we_know_what_texture_the_skin_of_an/
|
{
"a_id": [
"erjwn65"
],
"score": [
3
],
"text": [
"To address dinosaurs specifically at least, I'll copy my answer from a similar previous question here: \n\n > Though they are much rarer than skeletal fossils, there are examples of fossilized skin imprints that indicate what extinct dinosaurs might have looked like. For example, see this [extremely well preserved *Borealopelta*](_URL_2_) specimen (though standalone fossils like [this one from an *Edmontosaurus*](_URL_3_) are more common. And we do in fact know that many dinosaurs *did* have feathers, from fossils which preserve them like [this *Sinosauropteryx*](_URL_5_). \n > \n > Though there are many species for which we don't have conclusive evidence of feathers yet, it's still possible to infer that they likely were feathered with techniques like [phylogenetic bracketing](_URL_4_). Here's a [cartoon](_URL_7_) (from [this blog](_URL_11_)) that illustrates how this technique suggests that *Deinonychus* had feathers even though we don't have physical evidence for this. Since vaguely feather-like structures have been found not only in theropods but in other groups of dinosaurs too (e.g., [*Psittacosaurus*' tail bristles](_URL_8_)), and even in non-dinosaurs like the [pycnofibres of some pterosaurs](_URL_10_), it's quite possible that a large percentage of dinosaurs had similar structures in some form.\n\nYour mention of fur also reminds me of similar discussion about the evolution of fur in the ancestors of mammals. There are several groups of extinct synapsids that, while not being mammals themselves, are more closely related to mammals than to reptiles. And, again largely based on fossil evidence, we have good reason to believe that many of them had fur, making it clear that fur predates mammals in the same way that feathers predate birds. The oldest known fossil with evident fur that I'm aware of is a Jurassic cynodont called [*Castorocauda*](_URL_1_)*,* described in [this paper](_URL_9_) (unfortunately paywalled). However, there is some more circumstantial evidence from fossilized feces that even older groups like the Permian [gorgonopsids](_URL_6_) may have had fur too ([source](_URL_0_)). So basically, while there are always features that will be difficult or even impossible to see in fossils, there are several lines of evidence that can be used to determine, or at least infer, the appearance of extinct organisms."
]
}
|
[] |
[] |
[
[
"https://onlinelibrary.wiley.com/doi/abs/10.1111/let.12156",
"https://upload.wikimedia.org/wikipedia/commons/0/0a/Castorocauda_BW.jpg",
"https://www.nationalgeographic.com/photography/proof/2017/05/nodosaur-fossil-discovery-science-photography/",
"https://i.imgur.com/AV6fkgM.jpg",
"https://en.wikipedia.org/wiki/Phylogenetic_bracketing",
"https://upload.wikimedia.org/wikipedia/commons/c/c5/Sinosauropteryxfossil.jpg",
"https://evolutionforskeptics.files.wordpress.com/2016/08/gorgonops_whaitsii1.jpg",
"https://2.bp.blogspot.com/-1op2-2uG7vY/WWR8qUY-TaI/AAAAAAAADQw/nRM76Bu_utwtU0EuWPDTAR6zhtLgvYACACLcBGAs/s1600/133.JPG",
"http://www.senckenberg.de/files/content/presse_joerdens/2016/psittacosaurus_modell_c_jakob_vinther_robert_nicholls.jpg",
"https://science.sciencemag.org/content/311/5764/1123.full",
"https://www.newscientist.com/article/2188405-stunning-fossils-show-pterosaurs-had-primitive-feathers-like-dinosaurs/",
"http://albertonykus.blogspot.com/2011/06/maniraptor-feathers-part-ii.html"
]
] |
|
15oqxs
|
how does an office chair function?
|
The rise/fall of the office chair confuses me. When it's at it's lowest and you raise it up, it sounds like you're releasing some kind of compressed air. Teach me reddit.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/15oqxs/eli5_how_does_an_office_chair_function/
|
{
"a_id": [
"c7oe4xf"
],
"score": [
3
],
"text": [
"When you sit on the chair and press the lever it opens a valve which allows air to compress and lower the chair. When you pull the lever without sitting on it, the compressed air pushes the chair back up."
]
}
|
[] |
[] |
[
[]
] |
|
1aahl6
|
what causes feelings of emptiness?
|
More specifically, that empty feeling that people generally associate with depression. Is there a reason for why our mind enters this state (or any state at all)? For me, I don't think I'm depressed, but occasionally, that terrible feeling will hit me for a while and then my mind moves out of it and I would like to be able to control it.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1aahl6/eli5what_causes_feelings_of_emptiness/
|
{
"a_id": [
"c8vjowa"
],
"score": [
3
],
"text": [
"There's no one cause. That kind of feeling can range from being part of the totally normal range of human experience — if your dog dies, you're *gonna be sad,* and that's not abnormal — to a cognitive problem, to a neurochemistry problem.\n\nIn general, cognitive problems are addressed with behavioral changes. If you get sad sometimes because life gets you down, or because you get stressed, or because you get lonely, you might benefit from finding a new hobby or making a new friend or something along those lines. That's a *normal response* to an *abnormal feeling.* If you feel abnormally sad, you can do something to address it. That works for most people.\n\nSometimes, though, people feel sad in ways they can't address with a new hobby or a day at the amusement park. That's *colloquially* what we call depression … though *clinical* depression is a specific thing that fits certain specific criteria, so be aware of when people are using the word casually (to mean \"I'm feeling sad and nothing cheers me up today\") and when they're using it clinically.\n\nSometimes clinical depression is the result of abnormal levels of certain neurotransmitters in your brain — dopamine, serotonin and norepinephrine, mainly. A healthy brain has a good balance of these neurotransmitters; when they're out of balance, all sorts of thinking-and-feeling problems can crop up. It's possible to influence the balance of neurotransmitters in various ways, from getting more exercise to sleeping better to taking (or abstaining from) various drugs. But that's getting into *medical* matters about which only a physician who knows you well can make a useful recommendation.\n\nSo really, the answer is there's no one cause. What you're describing happens to everybody sometimes, and can be caused by any number of things, and correcting it can be done in any number of ways from the simplest to the most complex, depending on your exact situation."
]
}
|
[] |
[] |
[
[]
] |
|
7p8h79
|
When people think of colonisation, they typically mean the Age of Colonisation. How different was Greek Colonisation, such as Massilia?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7p8h79/when_people_think_of_colonisation_they_typically/
|
{
"a_id": [
"dsfwy88"
],
"score": [
67
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"text": [
"When we think of colonization, we generally think of states making organised efforts to appropriate overseas territory by force, creating a periphery whose labour and natural resources are exploited for the benefit of the colonizing centre. Greek colonization was very different. Indeed, prominent scholars have argued that the word is entirely inappropriate, and we would increase people's understanding of the phenomenon if we stopped calling it that.^1\n\nThe most obvious point is that the word is anachronistic. The word \"colony\" and its cognates are derived from the Latin *colonia*, a military settlement intended to serve as an outpost and garrison of Roman power anchoring newly conquered territory. No such word exists in Archaic Greek and the so-called \"Age of Colonization\" (mainly the 8th and 7th centuries BC) predates its use by hundreds of years. Instead, Greeks referred to overseas settlements as *apoikiai* (literally \"away-from-homes\") and to the process as *apoikismos* (\"moving away from home\"). You'll notice that these terms are a lot less value-laden; they imply little more than settlements created by migrants, without any built-in sense of a power structure or of claims to conquered territory.\n\nThis is indeed perhaps the main difference between Greek settlement overseas and the processes of the Age of Colonization. While modern colonization is all about appropriation and exploitation for the sake of a remote colonizer, Greek *apoikiai* were not conquests, but autonomous communities. In the Archaic period, they owed neither tribute nor fealty to their *metropolis* (mother city). While they might retain similar cults and customs, and often paid ritual homage to their founders, they were free to pursue whatever policy they saw fit and were under no obligation to transfer any of their wealth back to the places they had left behind. On this point alone, it is clear that Greek \"colonies\" were not colonies; they were new but not inferior or subordinate communities. Their autonomy allowed some to rise to great prominence with no notable effect on their *metropoleis*. Settlements like Sybaris and Tarentum in Southern Italy, and Syracuse and Akragas in Sicily, became renowned for their great wealth and size, rivalling or even surpassing the states of Old Greece. Many of them became *metropoleis* in turn, sending out second-generation settlements, which might also send out their own settlements, until opportunities ran out.\n\nIndeed, Greek overseas settlements were detached from their mother cities in more than just a geopolitical sense. While individual communities in Old Greece often took the *initiative* to found a new settlement, and presumably provided a core group of settlers, the process of *apoikismos* was far less of an official state-sanctioned act than the word \"colonization\" implies. In the Early Archaic period, the states of Greece had seen only very limited institutional development, and it was simply not possible for any of them to control or manage an overseas empire. Instead, it appears that a colonizing venture was begun when either a state or a private person put out a call for volunteers, who might then gather from far and wide to have a share in the undertaking. This is the only way we can justify places like Phokaia, Eretria and Miletos allegedly founding *dozens* of overseas settlements without completely exhausting their own population. As the poet Archilochos observed, when the men of Paros settled on Thasos in the Northern Aegean:\n\n > The misery of all the Greeks has rushed to Thasos.\n\nIn other words, the process was not driven by states looking to expand, but by individuals and groups hoping to build a new life, with or without the sanction of a mother city. Often the more important sanction sought was actually that of the Oracle of Apollo at Delphi, which played a key role in assigning the direction of overseas settlement and is the likely source of many surviving colonization stories. As for the ventures themselves, some were prompted by a search for trade contacts, land, or specific resources like metals and timber; others by political exiles' need for a new home; others by local emergencies such as drought, famine, or displacement through war.\n\nThe earliest overseas settlements seem to have grown out of settling groups of traders, only a minority of whom would even be Greek. Pythekoussai, on Ischai in the Bay of Naples, is the earliest one (settled c. 770 BC) - and is identified as one of the possible places of contact where the Greeks may have learned their alphabet from the Phoenicians. The earliest \"proper\" *apoikiai*, meanwhile, like Megara Hyblaia on Sicily, show clear archaeological evidence of the presence of a range of different groups of Greeks and local populations. The most likely process of such early \"colonization\" was the arrival of a mixed group of Greek opportunists in a new land, in which they either forced out or found some way to live together with the people already present. In some cases the indigenous population was subjected and turned into rural slaves; in others, they formed distinct groups inhabiting their own parts of the new settlement, fading gradually into the Greek settlement through intermarriage and the adoption of foreign wares and habits.\n\nThe result of these processes of mingling and assimilation, both within the collective \"Greek\" settling population and between Greeks and local peoples, was that each overseas settlement's laws and religious practices were a mixture of things brought from home and things adapted to the local situation. *Apoikiai* provided an opportunity to create a community out of whole cloth, and while some traditions were copied from the mother city, others were drafted specifically to fit the need. Places like Megara Hyblaia and Metapontion are the earliest Greek urban centres laid out to a regular grid plan, with a space left open specifically to meet and conduct public and private business. Some of the earliest attested lawgivers, semi-mythical authors of states' customs and systems of government, operated in Sicily and Southern Italy rather than in Greece itself. Often new cities would copy each other, rather than simply adopting the laws of the mother city. Settlements that founded their own *apoikiai* might create 'families' of overseas Greek states, which spoke the same dialect and shared customs and religious cults. These states would then try to participate in panhellenic festivals, games and rituals in their own right, establishing their place as autonomous communities in the Greek world, and feeding back to Old Greece the ways in which they had organised their societies. \n\nIt is only in the Classical period that Greek practices of overseas settlement change. This is the time when old mother cities start to stake a claim to honour and special treatment from their 'children'; when Greeks of the same dialect groups begin to assert a form of kinship that had never been an issue in the mixed communities settled across the Mediterranean and the Black Sea; and when new overseas settlement takes on a very different, more imperialist character. \n\nIn the years between the 8th and 5th centuries BC, Greek states grew tremendously in size and complexity, and by the beginning of the Classical period the larger states had developed the ability to maintain and control far-flung domains composed of home territory, planted settlements, allies and subjugated communities. As a result, they began to see the value of overseas settlements as outposts of their sphere of influence, rather than simply as an escape valve for unwanted elements in society. In the Classical period, when states like Athens or Sparta found new cities elsewhere, it is understood that these cities are not wholly independent; they are extensions of the mother city, meant to represent its interests abroad. These places are intended to safeguard strategic positions, replace local populations, and assert the authority of imperialist states. The cities Athens planted in Thrace (Nine Ways, Amphipolis, Brea) were intended to give Athens ready access to the timber and mines of the area. Sparta's settlement of Herakleia in Trachis gave it an excuse to arrange the affairs of Central Greece as it saw fit. While the Corinthian settlements of Potidaia and Kerkyra were not of Classical date, the role they played in triggering the Peloponnesian War was much to do with Corinth appropriating these old daughter cities in the Classical way, demanding that its rights as a mother city were respected and using the opportunity to support those regarded as kinsmen in struggles to protect Corinth's interests. This is \"colonization\" of a kind we might recognise more easily, and one more worthy of its bloodsoaked modern name.\n\n & nbsp;\n\n1) R. Osborne, 'Early Greek colonization? The nature of Greek settlement in the West', in N. Fisher/H. van Wees (eds.), *Archaic Greece: New Approaches and New Evidence* (1998), 251-269"
]
}
|
[] |
[] |
[
[]
] |
||
1rg11s
|
It is said that history repeats itself. How do the issues of today reflect on the state of American society in comparison to how certain issues impacted great societies of the past?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1rg11s/it_is_said_that_history_repeats_itself_how_do_the/
|
{
"a_id": [
"cdmwvfs"
],
"score": [
2
],
"text": [
"I'm not 100% clear on the type of answer you are looking for, so I'm going to try to think about this a bit theoretically:\n\nThe old adage that \"history repeats itself\" tends to make one consider history as cyclical. Through this model of reading history, one might find that certain trends tend to re-emerge with each passing generation. In this case, it seems that you are interested in social issues/trends in particular. In my opinion, the \"issues of the day\" for any given society reflect the critical breaks in value systems within that society. However, what causes such divisions? My answer: the ones that came before them. As such, these \"breaks\" are not as much a cyclical trend as a linear one.\n\nWhat I'm getting at is that if one is going to compare how, say, slavery divided the American public in the 1850s to the debates over same-sex marriage today, one must consider the latter to be a product of the former. In American history, as with all forms of history (I happen to be a Europeanist), I find it difficult to compare social trends between two starkly different eras for the precise reason that they are starkly different eras. Rather, I'd be more inclined to study how a past issue evolved into a contemporary one.\n\nWith this particular example I'll try my best to elaborate *very* briefly (Americanists, please chime in). First, slavery became an extremely divisive issue before, during and after the American Civil War. With the effective subjugation of the American South, there was little this segment of society could do to stop the passing of the constitutional amendments that effectively ended slavery. This bred great animosity toward the North and established a degree of \"otherness\" between Northerners and Southerners. This divide would characterize American politics for generations and I might argue that it carries through to the present. Party affiliations shifted over time, but the South has remained rather socially and politically conservative, in my mind, as a backlash against Northern dominance that occurred 150 years ago. Thus, when one considers debates of same-sex marriage, abortion (pick your divisive issue), one must consider a linear trend and continuance in American history, not a cyclical one.\n\nEdit: formatting"
]
}
|
[] |
[] |
[
[]
] |
||
pkhim
|
the flat universe theory, and why it has zero total energy
|
How is the universe [Flat?](_URL_0_). This doesn't make sense to me in the slightest, clearly energy is used, so how does the universe have zero total energy? More importantly, why can the universe form from nothing if it does have zero total energy?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/pkhim/eli5_the_flat_universe_theory_and_why_it_has_zero/
|
{
"a_id": [
"c3q30rg"
],
"score": [
6
],
"text": [
"No one knows how a Universe can come from nothing but there are theories. Lawrence Krauss has new book \"A Universe from Nothing\" and several YouTube lectures (about an hour long each), one called \"A Universe from Nothing\" and another called \"Life, the Universe, and Nothing\". The zero total energy theory is (basically) that the positive energy of the expansion is exactly equal to the negative energy of attractive gravity. Makes a certain amount of sense, one is pushing out and the other is pulling in... it is a lot more complicated than that, but that is sort of the idea.\n\nBeing flat just means that all triangles have 180 degrees. The largest triangles we can measure include corners at the cosmic background radiation (clumsy language, sorry). Using those triangles the Universe cannot be said to be different than flat.\n\nIf the Universe is indeed flat, that also means it is infinite. Based on the triangle measurements (and some other evidence) if the Universe is not not flat than the smallest the Universe should be is about 250 times the size of the Observable Universe.\n\nSo the Universe is a wild, wonderful, awesome, confusing, and mysterious place. But the last 100 years of using high quality optics and powerful mathematics has given us an understanding that was impossible to even imagine before 1900. "
]
}
|
[] |
[
"http://en.wikipedia.org/wiki/Shape_of_the_Universe#Flat_universe"
] |
[
[]
] |
|
bh4ga3
|
why do gaming laptops with discrete graphics, i7 processors, etc not seem to function as well as desktops with the same specs?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bh4ga3/eli5_why_do_gaming_laptops_with_discrete_graphics/
|
{
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"elpxwtz",
"elq5dmp",
"elq6zc0"
],
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4,
7,
3
],
"text": [
"It probably has to do with the fact that laptops dont have a graphics card as big and as powerful as a normal gaming desktop would. Try playing a FPS on your pc without a graphics card... It runs like shit",
"Laptops sacrifice power for portability. Open up a desktop and there'll be plenty of room left over. Open a laptop of similar vintage, and everything is crammed in, tight! \n\nThe GPUs used in laptops simply don't have the room for the vast amount of VRAM etc needed for complex computations. They also have to be drastically more efficient, because laptops can't disperse heat nearly as well as a desktop can, nor do they have infinite electricity like a desktop does. \n\nAdditionally, when looking at the specs, look at the whole picture (specifically the numbers, and their benchmarks). Not to be condescending, but just because two components share a name, doesn't mean they're the same. The manufacturers use terms like \"I7\" and \"GTX1080\" because they know those name evoke confidence, when in actuality, the ones being put in laptops aren't anything like the ones built for desktops. \n\nTLDR: Laptops components are designed to be compact and both energy and heat efficient; not powerful. Desktops only need to worry about power.",
"The laptop i7 and desktop i7 are completely different chips, despite the name and generation on the label being the same. They are not the same. \n\nYeah... marketing boyee! \n\nAnyways, the laptop chips are meant to operate at very low power consumption (and produce less heat), and thus are generally WAY less powerful than the desktops operating at full throttle and requiring huge heat sinks on the cpu because they are burning hot with all that power. \n\nDesktop cpus are designed for power. Laptop CPUs are designed to save power and be portable. This comes at a massive loss in performance."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
1jwkgj
|
Is it possible for octane to freeze out of gasoline?
|
Octane's melting point is at -57 degrees C, which is warmer than polar temperatures. So, could a vehicle parked outside in one of these locations have the octane precipitate out of the gasoline?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1jwkgj/is_it_possible_for_octane_to_freeze_out_of/
|
{
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"cbj08oy"
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"score": [
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"text": [
"No. This form of distillation is possible with certain solutions, just not gasoline. In gasoline, a molecule of n-octane is interacting both with other n-octane molecules as well a bunch of linear and branched alkanes, all of which are chemically very similar to n-octane (but have different freezing points). The freezing point of the solution is determined by the interactions between all components in the solution. As the temperature drops, components that freeze at higher temperatures are effectively held in solution by their interactions with lower-freezing-point components. It should also be noted that many of the alkanes in gasoline freeze at much higher temperatures than does n-octane.\n\nAs an experiment, if you can get a bottle of vodka cold enough to freeze, you will notice that the water does not precipitate out."
]
}
|
[] |
[] |
[
[]
] |
|
37eru3
|
I have myopia. When I look in a mirror, objects behind me are blurry. Logically, shouldn't I be able to see these things clearly?
|
askscience
|
http://www.reddit.com/r/askscience/comments/37eru3/i_have_myopia_when_i_look_in_a_mirror_objects/
|
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"text": [
"No.\n\nSuppose that you're looking at something sitting 2 feet in front of a mirror. The image in the mirror would appear 2 feet *into* the mirror. The way the light rays bounce off the mirror and enter your eyes is exactly the same as though you were looking at the object sitting 2 feet on the other side of a window.\n\nIn short, the light has to travel from the object to the mirror and then to your eye. The distance traveled by the light, and thus your ability to focus it with poor eyes, does not change depending whether it bounces off a mirror first or travels directly to your eye.\n\nThis is of course assuming the mirror is a flat plane and not curved, which can help or hinder your ability to focus the light, like a glass lens in a pair of glasses. [This wikipedia article on curved mirrors explains how images are made by focusing light rays](_URL_0_)",
"The mirror isn't like a photo. It's not a 2D flat plane image onto which your eyes can focus like a poster. It's optically exactly like looking at reality through a window in the wall. Distances remain the same, since light rays that reach the mirror are simply redirected towards your eye, but their angles relative to other light rays are unchanged.",
"I think a good premise to this would be explaining myopia (as most of sight defect) is actually a defect which changes of the position of the focus point of the rays coming into your eye.\n\nThe eye actually uses the same principle of the \"pinhole cinema\" where [an image is recreated inside an obscure room ](_URL_0_) [Edit](_URL_1_)\n\nWhen the ~~crystalline (the lens our eyes use to focus the rays coming from outside)~~ the eye fails to properly focus the rays on the retina, we have problems with sight.\n\nIn myopia, the focus point is in front of the retina and therefore the rays proceed and spread rendering a blurry image on the underlying retina. \n[Here you can see an example with corrective lenses](_URL_3_)\n\nNote: the reversed tree in the previous image symbolize the point where it would appear at focus.\n\n.\n\nThat's why, as /u/walekj pointed out, if light rays hit a perfect mirror, [they are bounced off at the same angle from the perpendicular plane](_URL_2_) and therefore they appear as they were coming exactly from inside the mirror from a distance equal to your distance from the mirror plus the distance between the mirror and the object.",
"Some eye doctors literally don't have enough space in their tiny offices to accommodate the distance needed for the letter charts. When I had PRK done, the doctors office was so small, he had me look through two mirrors focused at each other on opposite sides of the room to simulate the distance needed to get the same effect.",
"If you imagine that the mirror is actually a window into a world that happens to be the mirror image of this one, you'll get the right intuition: you're looking at copies of those objects, that are sitting behind that copy of you. They *are* farther away.\n\nAnd that's not just a metaphor, it's a totally accurate representation of the optics of an ideal, planar mirror."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Curved_mirror"
],
[],
[
"http://www.cbakken.net/obookshelf/image194.gif",
"http://www.reddit.com/r/askscience/comments/37eru3/i_have_myopia_when_i_look_in_a_mirror_objects/crmc55q",
"http://sciencelearn.org.nz/var/sciencelearn/storage/images/contexts/light-and-sight/sci-media/images/types-of-reflection/685409-1-eng-NZ/Types-of-reflection.jpg",
"http://biology-forums.com/gallery/14755_27_08_12_12_25_00_82011157.jpeg"
],
[],
[]
] |
||
sv90g
|
What are random "flash memories", and what is going on in the brain when they occur?
|
Several times a day I experience random memories that flash into my mind for a second or two. They are usually very mundane memories from any time in my life, and have no relation that I can determine to what I am doing at the time that they flash into my mind. I have spoken to many people about this, and everyone seems to get these. What mechanism/process/reaction in the brain causes these to occur?
|
askscience
|
http://www.reddit.com/r/askscience/comments/sv90g/what_are_random_flash_memories_and_what_is_going/
|
{
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"c4h9azx"
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"score": [
5
],
"text": [
"Huh. I've never heard of this, and I do research into memory. Maybe I'm not understanding. Could you describe the situation more?"
]
}
|
[] |
[] |
[
[]
] |
|
3toi8y
|
the differences between satanic religions, forms of believes and sects
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3toi8y/eli5_the_differences_between_satanic_religions/
|
{
"a_id": [
"cx7wjkm"
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"text": [
"Generally there's two main forms of Satanism in the West. The first is LaVeyan Satanism which doesn't literally believe in Satan (or God), but believe that Satan is a symbol that represents the good life: rebelling against authority, giving people what they deserve, worship of the self, etc. A guy in the US named Anton LaVey started the Church of Satan in 1966, and he wrote the Satanic Bible and yeah, they're mainly just atheists who like the aesthetic. Sometimes they talk about \"Magic\" but they don't mean magic as a supernatural force, they interpret \"Magic\" symbolically as using your will to change the world around you. \n\nThe second, more minor variety, is theistic Satanism, which is people who believe Satan really exists and they worship him as their god. There's a lot of variety among theistic Satanists, and it's often hard to tell who truly believes what they claim to believe and who is treating it as symbolic. A few theistic Satanist \"churches\" are the Ophite Cultus Satanas, the Temple of the Black Light, and the Order of Nine Angles.\n\nIn addition, some Satanists are neo-Nazis or other white supremacist neo-pagans. And there also some neo-pagans who worship two gods, sometimes representing God and Satan, as two complementary forces in the universe. "
]
}
|
[] |
[] |
[
[]
] |
||
d9dgeu
|
how your internal clock works
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/d9dgeu/eli5_how_your_internal_clock_works/
|
{
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"Your body produces 2 chemicals that help regulate your sleep wake cycle: cortisol and melatonin. Cortisol is the \"awake\" hormone and melatonin is the \"sleep\" hormone. At night, your melatonin level rises and triggers sleep while cortisol levels decrease. In the morning, the opposite happens.\n\nYour body gets accustomed to these hormone levels changing at a certain time. One of the biggest factors for this is light. Light triggers the body to stop producing melatonin (which is why you should stay off electronics and dim your lights before going to bed). Other triggers such as temperature and pressure changes can potentially cause the swap.\n\nEdit: To expand a little bit, pretty much all of these changes are centered around a part of the brain called the suprachiasmatic nucleus (SCN) which is often referred to as the circadian clock. It takes in external stimuli (mostly light) and then triggers neural and hormonal changes and described above. How exactly this all occurs and the process of sleep is still not very well understood.",
"All biological clocks work on basically the same principle (regardless of human, plant or microbes). It just consist on a set of compounds which have an activation/repression mechanism between themselves, and the relative ammounts of such compounds will then activate/deactivate other functions such as sleep/activity or many other things. I'll put an example of molecular clock which works on 2 components, but they are usually more complex).\n\nThe cell has genes encoding for 2 compounds: A and B, where the compound A activates the gene for B, and B represses the gene for A. The way it goes is the following: from the initial state (none of the compounds have been produced), gene A is active and the cell produces compound A, which starts to accumulate. As concentration of A increases, it will start activating the B gene, hence B's concentration will increase as well. As B accumulates, it will start supressing A until its production completely stops. That will cause A's concentration to decrease, and as it does so, gene B won't be activated anymore, so gene B will decrease its activity and it's product starts decaying as well. Once compound B's amount is low enough, gene A will be activated again, restarting the cycle. \n\nThis process results in a molecular dynamic which can be interpreted as coordinated waves with a constant length or duration, which can then be further adjusted by external factors via cortisol/melatonin as other comments already explained.\n\nEDIT: spelling",
"You know the excuse \"Sorry I'm late Boss, my alarm didn't go off.\"\nIt's a common excuse for a reason. Many people in fact do NOT wake up by themselves. (Even if they go to bed at a reasonable hour.)\n\nWhile a good amount of us do have a working biological clock, there are many of us who use an alarm clock for a reason. \n\nThat being said, i tell my body, listen punk, tomorrow we are waking up at X:YZ Time and if you dont I will punch you in the gut!\n\nTough Lough works! I used to punch myself in the gut all the time, and now I almost never have to.. I can go to sleep at 11pm and if i have to wake up at 4am the next day, my body will do it for fear of my threats."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
1672hg
|
Do overweight people have an increased capacity for heat evaporation due to larger skin surface?
|
compared to if that same person had not been overweight. just curious.
|
askscience
|
http://www.reddit.com/r/askscience/comments/1672hg/do_overweight_people_have_an_increased_capacity/
|
{
"a_id": [
"c7tbthv"
],
"score": [
5
],
"text": [
"wouldn't they have proportionally less surface area vs. mass (as the surface area grows as a squared exponent while the volume grows as a cubed exponent)?"
]
}
|
[] |
[] |
[
[]
] |
|
75idsk
|
are rechargeable batteries better fiscally/environmentally vs. disposable ones?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/75idsk/eli5_are_rechargeable_batteries_better/
|
{
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"text": [
"Fiscally no question they are better. Environmentally I am unsure. But the energy required to charge a AA battery costs pennies so assuming you use them regularly they will make their money back quickly.",
"Because you only buy them once, and you don't throw them away. \n\nOne $10 battery costs less than 100 $2 batteries, and throwing away 100 batteries is more trash than throwing away one battery. ",
"Rechargeable batteries are absolutely better than disposable ones environmentally, including all aspects of their life, ie. including production, use, and disposal.\n\nIt's difficult to condense a life-cycle assessment into an ELI5 but across the board for factors like acidification, heavy metal pollution, and climate change contribution rechargeable batteries (assuming an optimistic recharge number) range between 50 and 140~ish times less of an impact.\n\nThe biggest impact comes from the production of the battery itself.\n\n[Source](_URL_0_)"
]
}
|
[] |
[] |
[
[],
[],
[
"http://www.fraw.org.uk/library/tech/parsons_2007.pdf"
]
] |
||
dppfpu
|
why would less population in the future be a bad thing? i thought the world is already overpopulated.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/dppfpu/eli5_why_would_less_population_in_the_future_be_a/
|
{
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"f5x978j"
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"text": [
"Almost every governmental financial policy is based on the assumption that the economy / GDP will keep growing larger, and thus tax revenues will continually increase. Businesses will get more efficient, more goods will be produced and - most importantly for our discussion - more people will exist to create and consume those goods. \n\nIf there is a significant population decline, then the economy / GDP will _shrink_ and all of the programs that were based on the concept of a growing economy will suffer serious financial shortfalls. For example, social security: Social security only works because the people working _today_ are paying into the program at a rate that exceeds the number of retired people drawing funds from that program. A significant population decrease would mean that there is not enough money to pay people who are eligible for SS. Cutting of an income stream (for many, their _only_ income stream) to a section of the population who is more-or-less unable to return to the workforce would cause massive rates of poverty among the elderly, which would not be good for the country as a whole.\n\nThat is just one example."
]
}
|
[] |
[] |
[
[]
] |
||
9t2jb6
|
How did Romans dredge silt from harbors?
|
Many harbors after the fall of Rome were either abandoned because they silted up, or had to move because the coast eventually moved out to sea and the original location was now far inland. In some cases they ended up miles away from the ocean after a few centuries. Clearly it was a costly and labor intensive task or else post roman societies would have continued it. I believe it involved some sort of boat with an "arm" of some sort to dig up the sediment, but I have not come across any detailed explanation of how exactly romans would remove thousands of square feet of mud from the bottom of the harbor?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/9t2jb6/how_did_romans_dredge_silt_from_harbors/
|
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"text": [
"Do you have any examples of these inland ports? I'd love to check them out on google maps :)",
"This is an interesting question, and this thread is a wasteland of deleted replies. I've been doing a bit of looking around and I am not finding very much discussion of the *hows*. Vitruvius, in his *de architectura,* mentions in passing the operations to dredge harbors at several cities in Asia Minor (on the modern western coast of Turkey). We know that due to geomorphological, hydrological, and human-influenced factors, these harbors were \"silting\" rapidly at the end of antiquity, and in fact today are in some cases now several miles inland. At Ephesus in particular, the Romans seem to have fought a stubborn but futile battle against the silt. There are a lot of technical stratigraphic studies of ancient dredging attempts, in Asia Minor and also in Marseilles and at the mouth of the Tiber, for example. [This paper](_URL_1_), which is all over the internet and clogs up searches, is a good example of the kind of scientific work that can be done on the question of dredging. Figure 8 in that paper shows the remains of an ancient ship, 1st or 2nd century CE, which most agree had something to do with dredging operations. It has a central \"well\" (hole) in the bottom of the hull through which the \"arm\" of dredging machinery passed. I am not at all an expert on how the engineering would have worked. Their figure 9 shows how it was done almost two millennia later, if that's any help. The technical papers all show plainly that the dredging operations were extensive in the Roman Imperial period in several key cities; we just don't have good evidence to say more in this case, at least not as far as I can find. \n\nI also found [this thread](_URL_0_) from four years ago that talks about dredging. /u/iwinagin talks with some better authority than I can muster on the different methods."
]
}
|
[] |
[] |
[
[],
[
"https://www.reddit.com/r/AskHistorians/comments/2jvx1v/how_were_ancient_ports_harbors_made/",
"http://www.academia.edu/697399/Mind_the_stratigraphic_gap_Roman_dredging_in_ancient_Mediterranean_harbours"
]
] |
|
ncf73
|
The Earth's gravity is strong enough to keep orbiting spaceships/stations from flying off into space, so why do people on board seem not to experience it? Shouldn't they be drawn down towards the Earth-side of the spacecraft?
|
askscience
|
http://www.reddit.com/r/askscience/comments/ncf73/the_earths_gravity_is_strong_enough_to_keep/
|
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"c380p5e"
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"text": [
"They are drawn towards the earth the same as the spacecraft in orbit. They're in orbit too.",
"Because they're in free fall. It's like when a plane dives and you feel weightless for a second. In fact that's how they simulate the effects.",
"In terms of gravity, an astronaut orbiting in a space station is exactly like a person in a free falling elevator.\n\nBoth the person and the container are being pulled by earth's gravity, but since they are moving in the exact same direction in the exact same way, there is no *relative* motion due to gravity.",
"Get rid of the idea that they are floating. In actuality, the spacecraft and everything inside it is a projectile circling the earth at thousand of miles and hour. They appear to be floating, but they are really moving very fast around the earth. If the space shuttle were to lose enough of its velocity, it would then fall back to Earth. ",
"They are drawn towards the earth the same as the spacecraft in orbit. They're in orbit too.",
"Because they're in free fall. It's like when a plane dives and you feel weightless for a second. In fact that's how they simulate the effects.",
"In terms of gravity, an astronaut orbiting in a space station is exactly like a person in a free falling elevator.\n\nBoth the person and the container are being pulled by earth's gravity, but since they are moving in the exact same direction in the exact same way, there is no *relative* motion due to gravity.",
"Get rid of the idea that they are floating. In actuality, the spacecraft and everything inside it is a projectile circling the earth at thousand of miles and hour. They appear to be floating, but they are really moving very fast around the earth. If the space shuttle were to lose enough of its velocity, it would then fall back to Earth. "
]
}
|
[] |
[] |
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[],
[],
[],
[],
[],
[],
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||
3222zu
|
Was it common practice for ancient historians to cite their sources?
|
I'm specifically talking about historians in the Greek and Roman world, say 2,000 years ago.
Would most historians mention where they are getting their information?
Were historians who cited sources considered more reliable (or are they considered more reliable today, for that matter)?
How did they cite sources if they did?
-I'm asking because I've been arguing with people about the Book of Acts. I have been told that it is common and accepted to anonymously write fantastic, miraculous stories without mentioning sources. I am looking for more information regarding that time period and the practices of historians within it.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/3222zu/was_it_common_practice_for_ancient_historians_to/
|
{
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"text": [
"Well, Herodotus is another case of weird ancient history. In his book the Histories he talks about his methodology, which was to travel around and collect history from people as they told it. As you can imagine his book is full of tales of monsters and gods and stuff like that. \n\nInterestingly he does mention at times that he thinks certain stories are ridiculous, but then carefully mentions that he must remain consistent and that he is gathering histories as told by the locals. So a lot of times he will sort of cite sources by saying: \"I heard this story in Egypt from the priests at the temple of Ted.\" Or something like that.\n\nSome of the commentary I read about his works was that it was probably more reliable for what was recent history at the time. So if he says, \"Last year the river flooded.\" That is probably pretty reliable, while if he says \"A thousand years ago there was this massive fire that made popcorn.\" Less so.",
"According to Anthony A. Barrett in the introduction to Tacitus *The Annals*, ancient historians were more concerned about improving upon the work of their predecessors than paying particular attention to primary sources. They also generally didn't mention their sources by name, more often simply saying 'people' or 'certain writers' etc. \n\nTacitus himself mentions using some primary sources, such as the *acta diurna* (Daily Record) and directly mentions using the Senate records himself on one occasion. He also sometimes mentions in the text where his sources diverge and so shows how what one person says differs from another. Tacitus is also very interesting because we can check what he said against inscriptions found. For example, the *Tabula Hebana* gives a list of honours approved for the late Germanicus by the Senate. Tacitus gives quite a negative impression of Tiberius in his handling of the ceremonies; he and his mother were absent during the ceremonies to mark Germanicus' death and they put pressure on Germanicus' mother Antonia not to take part. However, the inscription shows Tiberius being very actively involved, delivering eulogies himself. \n\nIf I remember correctly, Thucydides, although stating how he will be objective and careful, never actually mentions any primary sources. Edit#: Also, Seutonius in his *Lives of the Caesars* actually uses some letters sent by various emperors (Augustus in particular I think) since he probably had access to these when working in the imperial court."
]
}
|
[] |
[] |
[
[],
[]
] |
|
2ui848
|
why do airlines now ask you to unplug smartphones from chargers during takeoff and landing?
|
I've heard this now in a few flights. They will announce that during take off and landing phones may be used in airplane mode but that they must be unplugged from external batteries or other charging devices. Any explanation?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2ui848/eli5_why_do_airlines_now_ask_you_to_unplug/
|
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"text": [
"I know the initial reason they banned using electronic devices during takeoff and landing is because those are the times that something is most likely to go wrong with the plane, so they don't want you distracted in case you have to react quickly to accident. So maybe it's the same reason? Maybe it's to prevent a tripping hazard in case of an evacuation?",
"Actually, if I remember correctly, once the plane goes into takeoff or landing mode, typically the plugs stop working and normally IFE (In Flight Entertainment) also shuts off.",
"The most likely scenario is to reduce the chances of any electromagnetic interference from the sources inside the phone or most likely be chargers themselves.\n\nWhen you put the device in airplane mode, it turns off the radios (which are intentional radiators that send signals through the antenna - no signal no interference risk) when you plug in the charger, you are basically introducing a long antenna (the wire) and a very noisy signal (the current going through the wire to your battery) - all do chargers today use a thing called PWM, pulse width modulation - where they send a square wave (in the order of hundreds of kilohertz) and adjust the amount of time that the square pulse is ON based on the amount of power to send though - (narrow rectangular pulse for low power, wide rectangular pulse for high power) \n\nSquare waves are very very noisy signals and the higher order harmonics can certainly cause interference, especially with the strength of the currents involved in charging. \n\nI worked as an EMC design engineer for a phone manufacturer, and our job was to make sure the phone did not emit any interference during operation. This Included battery charging - not only can you radiate interference through the charging cable, but you could Inject interference into the source (think so outlets in an apartment) imagine I'd those got into the circuitry of the airplane!! \n\nPhone manufactures go to great lengths and several rounds of certifying to make sure they don't cause interference - however from the FAQs perspective, users could end up buying cheap cables or chargers from China (and we know this and have evidence of this) and thus creates huge unknown risk. Even though it's not likely, the FAA takes no chances with these things. ",
"They wanna see how much shit they can keep you from doing before you become wise to their plan and rebel."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
1e96ey
|
Why is styrofoam squeaky?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1e96ey/why_is_styrofoam_squeaky/
|
{
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"text": [
"There was a good answer to a very similar question [here](_URL_0_) a few months ago:\n\n > Styrofoam is mostly air, and is otherwise walls of the polymer polystyrene. The reason that it is so squeaky is that when something rubs against it, on the microscopic level, there is a \"stick-slip\" interaction between the surface of the box and, say, your finger. When you \"stick,\" friction compresses the small bubbles (walls) of the polymer, and when you \"slip,\" your finger moves to a new spot. In this time, your finger is off of the surface, and the bubbles that you compressed now expand, contract, expand, contract, and do this at the frequency (-ies) that you hear the squeak. It is loud because the entire box effectively acts like a resonator- the energy dissipated from the scene of the \"stick-slip\" causes secondary oscillations from neighboring bubbles.\n\n > Dip your finger in grease, which will cause less of the \"stick\" when trying to recreate the squeak. No sound, right?\n\n > This is all based on friction between the \"sticky\" polystyrene and (using a musician word here), a mallet.\n\n**TL;DR: The molecular structure of expanded polystyrene gives it high-friction surface, so when you rub it against itself or your finger, \"slip-stick\" happens at the interface. EPS' low-density, high-air composition allows for high-frequency resonance.**",
"Stiction is what makes the noise. But why is it so loud?\nBecause styrofoam is both stiff and low mass. This makes a small vibration affect a large surface area, causing the greatest coupling with air making sound waves. If Styrofoam was more soft, the vibration would be more localized. If it were higher mass, its vibrations would have smaller amplitude."
]
}
|
[] |
[] |
[
[
"http://www.reddit.com/r/askscience/comments/16k06v/why_do_styrofoam_coolers_squeak_so_horribly/"
],
[]
] |
||
3ehzjb
|
how does someone get tss with a tampon?
|
I guess not really explain like I am 5, but.... in simple terms how does,whatever it is, occur?
Because I've heard various different things such as it happens with regular use, it happens when people are stupid and unhygienic, it happens because it makes a cut, it happens because it dehydrates one.
So what is it?
Haha thanks!
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3ehzjb/eli5how_does_someone_get_tss_with_a_tampon/
|
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"text": [
"The link between high absorbency tampons and TSS isn't completely understood. It may be because high absorbency tampons are left in longer, allowing bacteria to grow, while less absorbent ones must be replaced faster. Or, it may be because a drier tampon is more likely to cause little tears in the vaginal wall, letting bacteria enter. Staph infections (TSS is just a staph infection that has spread throughout the body) can be caused anywhere on the body just by a little cut. You don't have to be unhygienic or stupid for that to happen.",
"Tampons provide a medium where bacteria can grow without interference by the body's immune system. The bacteria are then strong enough and plentiful enough to attack the body in numbers too great for the body to defend against. Normally, if you have a staph infection on your skin, you see it and it hurts and you are aware of it and go to get medical treatment quickly. But you're not looking inside your vagina, and the vagina doesn't have much in the way of pain receptors, so you feel nothing. This allows the bacteria to get worse with no medical intervention, so by the time you have symptoms and seek medical attention, you've already got a whole systemic infection that is overwhelming your organs and causing circulation problems and can kill you."
]
}
|
[] |
[] |
[
[],
[]
] |
|
jblvx
|
whaling and why countries still use it today.
|
Can someone explain why countries still do whaling? I know it was used for insulation and food long long ago, but why do countries like Iceland and Japan still do it today? Also, how is it economically beneficial if so many other nations look down upon it?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/jblvx/eli5_whaling_and_why_countries_still_use_it_today/
|
{
"a_id": [
"c2arihk",
"c2arihk"
],
"score": [
2,
2
],
"text": [
"Because whales are tasty.",
"Because whales are tasty."
]
}
|
[] |
[] |
[
[],
[]
] |
|
3mrjb4
|
what are the chances of my keyless entry unlocking somebody else's car?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3mrjb4/eli5_what_are_the_chances_of_my_keyless_entry/
|
{
"a_id": [
"cvhj4z1"
],
"score": [
7
],
"text": [
"this is what i found online: \n\"Given a 40-bit code, four transmitters and up to 256 levels of look-ahead in the pseudo-random number generator to avoid desynchronization, there is a one-in-a-billion chance of your transmitter opening another car's doors.\""
]
}
|
[] |
[] |
[
[]
] |
||
27ly3u
|
why do companies like redbull and monster spend so much money on sponsorship and advertising when everyone knows them?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/27ly3u/eli5_why_do_companies_like_redbull_and_monster/
|
{
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"text": [
"Part of marketing and advertising is to generate impulse desires in consumers. You see a commercial for McDonald's, they talk about a Big Mac, you want a Big Mac, you go out and buy a Big Mac. \n\nEven if they can't compel you to go out and buy a can immediately, Red Bull and Monster are just trying to keep themselves at the forefront of your mind the next time you're shopping for an energy drink.",
"Also in line with keeping their brand popular, these brands got to that point by sponsoring. It's why they are more popular than other energy drinks. ",
"It's also about brand association. \n\nThey want to target their brand within a target market - a cool, young-oriented market. \n\nViews of these sports are usually more young and active. Hence the brand sponsorship and placement in these areas. ",
"You know them, but if they stop talking about themselves, you'll forget them. ",
"There's a reason Pepsi outdoes Coke in taste tests and Coke still moves more product, and it's advertising. Coke is the most drank soda in the world, yet they spend more on advertising than any other as well. Like others said, if they stopped barraging you with nonsense then someone else would, and consciously or subconsciously people will gravitate towards the new boss.",
" > When everyone knows them\n\nThere is your answer. ",
"Also, in the case of Redbull, their extreme sports venture makes them a lot of money, one of their snowboarding videos generated over two million dollars in revenue through iTunes. So it's not just advertising in this case, it's very lucrative venture for them. Also, in Formula 1 and WRC the manufacturers use it as testing ground for new technology. So it's more complex than just advertising or sponsorship for big brands.",
"Oh hey, you mentioned energy drinks. I'm thirsty.\n\n*There ya go...*",
"RedBull and Monster are aspirational lifestyle brands; the intended outcome of the marketing is that you feel like you are part of the marketed lifestyle when you consume their product.\n\nMarketing isn't simply about brand awareness. It could be argued it is more about maintaining an image than creating one.",
"Because they are trivially replaceable. The moment people stop thinking about them as being \"the\" energy drink, is the moment they have to start competing based on cost, quality, etc. With this level of advertising they can charge whatever they want. ",
"I can't find the quote from Coca Cola's advertising lead but it went something like this:\n\nJust because a plane is already in the air flying, you' don't turn off the engines.",
"i'm pretty sure they're both heavily infested into sports, so sponsorship is part of the package",
"Everyone knows them *because* they spend so much in advertising. ",
"A big part of premium brand advertising is not aimed at new customers. What they are doing is giving the current users the reason to not move down to the similar, cheaper models. This is also why mature companies frequently have very abstract adverts without an obvious call to action or offer to bring in new customers.\n\nThinking of buying supermarket own brand energy drinks? That badass who jumped from space wasn't on that. Prefer a Skoda to a Merc? You'll never be that guy with the beautiful girl racing round country roads. Want a cheaper stout? It won't rise slowly and satisfyingly in the glass to a rich and heavy head like Guinness will.\n\nMost people know these huge brands are more than the others, but they buy them and continue to buy them due heavily to a perceived gap in quality. Large scale marketing heavily weights and creates this gap, and keeps regular customers convinced they are right to keep spending that bit more.",
"how do you think everyone knows them? ",
"When people choose a favorite brand, they tend to stick with it as \"their\" brand. \n\nBecause of this, most ads are aimed at \"new\" consumers. Most new consumers are young people. This is probably 10 to 12 years old for soft drinks. I'm defining consumer here as the person who makes the buying decision, rather than their parents. \n\nThose new consumers are constantly being born. If you stop advertising, you lose the new consumer, and eventually your brand and its popularity die off. It only takes a couple years for a brand to die. ",
"Redbull isn't an energy drink company, they're a media company that also happens to sell energy drinks.",
"Having taken a basic marketing course, the answer is that they're reminding you that you want it. Reinforcing your desire. No ragrets.",
"If they don't take the sponsoreship or the ad, their competition will.",
"The only reason you know them is because they spend that much on advertising in the first place.",
"Why do you think everyone knows them?"
]
}
|
[] |
[] |
[
[],
[],
[],
[],
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[],
[],
[],
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||
aesp39
|
how do animals like lions, tigers, etc. carry their young by their mouth without hurting them?
|
Do they have a method as to not hurt their young? Genuinely unsure on this.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/aesp39/eli5_how_do_animals_like_lions_tigers_etc_carry/
|
{
"a_id": [
"eds7j31",
"eds7mcz",
"edsek50"
],
"score": [
10,
5,
3
],
"text": [
"It's easy, they don't bite it full force, just the way you don't instantly snap a pencil by chewing on it",
"Their young have a \"scruff\" on the back of their neck. Basically thick, loose skin.\n\nRegular pet cats and dogs have this, too.",
"Mirroring other answers, they have a specific piece of extra, thicker skin on their neck called a scruff. Their parents also bite only as hard as they need to. Might be a vicious looking bear or something, but their maternal instincts are still strong and they’re gentle with their young. Also, when they are picked up by the scruff, the babies become almost paralyzed, or at least really docile (their brain pretty much gets flooded with “chill out” signals). This causes them not to struggle, so their chance of injury is minimized. FYI this works even if you as a human pick a puppy or kitten up by their scruff."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
332p9i
|
how did anime go from being relatively innocent and cartoonish to highly sexualized characters?
|
If you compare Speed Racer or Robotech, for example, to modern series like Naruto, One Piece, Bleach, "harem" anime, etc., it's immediately apparent that anime has changed to include highly more sexualized characters and mature scenes. As a westerner, I especially can't understand how there are so many underage girls with in some series. AFAIK, these shows are not shown late at night. Isn't it simply pedophilia and against Japanese morality? Where was the turning point for anime?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/332p9i/eli5_how_did_anime_go_from_being_relatively/
|
{
"a_id": [
"cqgxxiw"
],
"score": [
3
],
"text": [
"A big part of it, I think, is that Japan doesn't have the same views on sex as the West does. (Most of the times that Japan's views on sex do match up with the West, it was because of imperialism.)\n\nTo some degree, it's a result of anime becoming more developed and popular with more audiences. \n\nThere was sex back then. Cutie Honey came out in the 1970s (also Robotech is the westernized version of the original Macross). \n\nA lot of these shows are meant for teenagers, not for children or adults. And Japanese teenagers are just as horny as ours. \n\nAnd hey, sex sells. That is the same in every nation. "
]
}
|
[] |
[] |
[
[]
] |
|
2xllto
|
why, if human bites almost always become infected, do we lick our wounds?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2xllto/eli5_why_if_human_bites_almost_always_become/
|
{
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"cp16ztr",
"cp17gku",
"cp17nl5",
"cp18d27"
],
"score": [
9,
3,
33,
15
],
"text": [
"I always assumed licking wounds came from dogs or cats.",
"There is a compound in human saliva that speeds up the healing process^[\\[1\\]](_URL_0_). It's suspected that the same thing is found in other animals, which is why they lick wounds too.\n\nThe problem is that there's still a danger of infection. Human mouths are full of bacteria that can cause infections. If I had to guess (seriously this is just a guess don't take this as medical advice) I'd think that smaller wounds don't get infected because if bacteria from your mouth does get in your immune system can overwhelm it. In a bigger wound maybe there is too much bacteria for your immune system to handle so you're more likely to get a lasting infection.",
"In addition to adding saliva that helps blood to clot, when you lick a wound that might have germs in it, you expose your tonsils and other specific organs to the germs. Those organs are used by the immune system to quickly identify, and respond to germs. \n\nLike capturing a few enemy soldiers, and torturing them into giving up the invasion plans for the rest of the body.\n\n_URL_1_\n_URL_0_",
"We can absolutely infect our wounds with our own saliva. Although saliva does contain a variety of proteins that are involved in (among other things) destruction of pathogens and promotion of wound healing, it is by no means safe to lick your wounds. You obviously will not infect yourself every time but you increase your risk of infection when you lick your wounds.\n\nYour saliva has millions of bacteria floating in it, many of them very capable of causing disease. It **does not matter** that these bacteria live inside you already, they can still very easily hurt you. Many infections (and essentially all oral infectious disease) are caused by microbes that are already on or in your body. \n\nThe reason bite wounds are often more dangerous than licking your wounds is that bite wounds often are associated with other types of trauma such as a deeper puncture type wound or crushing of the surrounding tissue. This damage makes it harder for your body to respond to bacteria that get into the wound and increases the chances of infection. \n\n\nSource: Personal and professional experience as an oral microbiologist."
]
}
|
[] |
[] |
[
[],
[
"http://www.sciencedaily.com/releases/2008/07/080723094841.htm"
],
[
"http://www.todayifoundout.com/index.php/2013/07/what-do-tonsils-do/",
"http://www.hmh.net/HMHWebsite/Service.aspx?PageID=178"
],
[]
] |
||
a67b31
|
how did spacecrafts come back to earth from the moon? did the lack of earth-like atmosphere on the moon interfere somehow?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/a67b31/eli5_how_did_spacecrafts_come_back_to_earth_from/
|
{
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6,
7,
2,
2
],
"text": [
"Very very carefully they put the pieces of their spaceship back together and very carefully let the computer navigate home. Lack of atmosphere = lack of anything to interfere. ",
"The lack of an Earth-like atmosphere on the Moon made it possible to design a spacecraft that could land carrying a spacecraft that could take off. Just look at how much harder landing on Mars is, and how really hard taking off and returning to Earth from Mars has been.",
"Landing on the moon without an atmosphere was harder than getting off the moon without an atmosphere.\n\nHaving an atmosphere means that as you go faster, you get more resistance to acceleration as the air has less time to move out of the way and let you pass. Think about moving your legs in water versus moving your legs through the air; the water is more dense and the faster you move your leg the harder it is to do/the more energy you exert for incremental gains.\n\nMost engines that we use for everyday applications extract oxygen from the air to help fuel their combustion. Rocket engines don't do this; the fuel contains an oxidizer, so that the rocket can create thrust in the vacuum of space.\n\nLanding on the moon, as it had no atmosphere, was a matter of using a rocket to counteract the momentum that was gained during the descent to the surface.\n\nGetting back to the earth from the moon is conceptually as simple as pointing your rocket the correct way so that you break free from the moon's orbit in such a way that your new orbit around the Earth dips into the atmosphere, which acts as a brake (aerobraking is the technical term) so that you don't need any further fuel to de-orbit the earth.\n\nI can't go too much more in depth without a crash course on orbital mechanics and the basics of rockets, but the concept behind what I just described is called a free return trajectory.",
"The spacecraft that landed on the moon never returned to Earth, there was a module orbiting the moon and a small two stage lander that would go from there to the moon's surface using the descent stage. On the way back the lander separated from the descent stage and returned to the orbiter using the ascent stage. Then the astronauts boarded the orbiter again and came back to Earth on it, leaving the lander there since it was a dead weight.\n\nThe lack of atmosphere on the moon didn't interfere because there's no gas to interfere, this saved the lander the need for any aerodynamic design. On the other hand this meant it couldn't leverage the atmosphere to slow down during the landing, as the spacecraft that return to Earth do, thus the need for a descent stage that would use a rocket engine to slow down.",
"Have you seen pictures of the spacecraft that landed on the moon? The bottom part of it stayed on the moon, but the top part of it had a rocket engine in the bottom. It came off and flew upwards into orbit around the moon. In orbit was the main spaceship. So the part that went to the moon and the part that stayed in orbit docked, and they fired their rocket to go back to towards the earth.\n\n & #x200B;\n\nBefore they reached the earth, they broke off all the pieces of the spacecraft other than the bit with people inside, and rode that down to the ocean.\n\n & #x200B;\n\nThe lack of atmosphere on the moon helped. Because of it they didn't have to worry about wind knocking things over, and didn't have to worry about air resistance coming down or going back up, so they could use a very light spacecraft."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
||
1yqy91
|
what part of the brain controls typing? is it similar to knowing a foreign language?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1yqy91/eli5what_part_of_the_brain_controls_typing_is_it/
|
{
"a_id": [
"cfmylob",
"cfn00h2"
],
"score": [
2,
2
],
"text": [
"This doesn't quite answer your question but it's a pretty cool relevant story about language and typing.\n\nI'm fluent in English and Chinese, but I can only recall memorized things easily in the language I memorized them in. For example, one of my old passwords I use is a 14 digit long string of numbers. I know it perfectly in English and can recite it perfectly in English. But in order to recite it in Chinese, I would need to visualize the numbers and slowly \"translate\" it into Chinese. Later I realized that my fingers know the positions so well that I can \"translate\" these numbers can very quickly recite it in Chinese by thinking about my fingers typing them out on a keyboard instead of visualizing the actual numbers.\n\nI'm sorry this doesn't actually answer anything but I just think it's can interesting story that's kind of relevant.",
"It's [muscle memory](_URL_0_). You've done it so much that you don't need to think about what you're doing. So it's more similar to riding a bike than learning a foreign language. "
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Muscle_memory"
]
] |
||
8i4hn7
|
- camera shutter speeds and their effects
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8i4hn7/eli5_camera_shutter_speeds_and_their_effects/
|
{
"a_id": [
"dyou4fg"
],
"score": [
2
],
"text": [
"The shutter speed is how long the image sensor is exposed to light. Light hitting the sensor makes the image. The shutter covers the sensor and opens and closes very fast to expose the sensor to light for a short time which is why photos are snapshots of time. \n\nThe faster the shutter opens and closes the less time the sensor is exposed to light, so the darker the image will be and sharper because less time is being exposed to the sensor. \n\nThe slower the shutter opens and closes, the more light is exposed to the sensor so the brighter the image is. The image will also be more blurry because movement in the image like people walking or cars moving are captured by the sensor into one image so the moving objects are blurred. \n\nIf you took a picture of someone walking with a shutter speed of 1/100 of a second, which is fairly quick, the image will be dark and he person will be crisply captured in a very brief moment of fine. If you took the same picture at 1/10 of a second, which is much slower, the man will be blurry because the sensor was open long enough to capture his movement. The image will also be brighter because the sensor was exposed to light for longer. "
]
}
|
[] |
[] |
[
[]
] |
||
7lkmwo
|
Did ancient people knew their quoted numbers of troops were baloney?
|
I know it was difficult to field large armies in the past partially because there just weren't that many people around and partially because of how inefficient they were at producing resources.
But when ancient sources quote ridiculous numbers for their army sizes, e.g. Herodotus claiming Xerxes had 2 million soldiers assembled at Thermopylae, did Herodotus *know* he was asspulling these numbers? Did ancient generals do headcounts? Did they even really need to know how many men they had? Were they just not good at estimating numbers of men by eyeballing it?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7lkmwo/did_ancient_people_knew_their_quoted_numbers_of/
|
{
"a_id": [
"drn48gt"
],
"score": [
125
],
"text": [
"Quite the contrary. They made a lot of effort to get the numbers right when they sized up enemy armies. They were also usually very specific about the number of their own troops. The problem is that we modern people tend to think of numbers as either true or false: empirical facts in the raw. They are actually a great deal more than that, and especially so in something like Herodotos' *Histories*. \n\nI'll start with that source and its infamous claims about Persian numbers. Yes, Herodotos says the Persians invaded Greece with a force of over 2,000,000 soldiers. Yes, this is obviously wrong; in the environment of Ancient Greece, such a force would be geographically impossible to fit and logistically impossible to feed. A century ago, Hans Delbrück applied his famous *Sachkritik* to the problem, using the reported size of the Persian camp and other ground rules to reach a more plausible estimate. Modern authors tend to estimate the size of Xerxes' army somewhere between 60,000 and 200,000 men.\n\nBut here's the thing: those figures are not based on any ancient evidence. They are nothing but informed speculation. The passages in which Herodotos reaches his absurd totals, on the other hand, are some of the most \"scientific\" of his entire work.\n\nWhen Xerxes' army is brought together in Asia Minor, Herodotos makes his first claim as to its size: 1.7 million (Hdt. 7.60.1). He goes on to explain how the Persians themselves established this figure:\n\n > They were counted in this way: ten thousand men were collected in one place, and when they were packed together as closely as could be a line was drawn around them; when this was drawn, the ten thousand were sent away and a wall of stones was built on the line reaching up to a man's navel; when this was done, others were brought into the walled space, until in this way all were numbered.\n\nModern scholars have rightly questioned this story; apart from anything else, it would have cost Xerxes a tremendous amount of time. But simply to say it didn't happen is to ignore the point of the passage. Herodotos was not satisfied to just give his readers the number. He thought it necessary to explain that it was reached by dividing the army into multiples of ten thousand and acquiring the total through empirical observation. In other words, far from \"asspulling numbers\", he insisted that his numbers were based on deliberate and painstaking scientific inquiry.\n\nSomething similar happens on the eve of Thermopylai, when Herodotos once again gives us the numbers of the Persian force (7.184-186). It is worth quoting this at length just to show how much work Herodotos does to justify his total:\n\n > Calculation proves to me that its numbers were still such as I will now show. The ships from Asia were 1,207 in number, and including the entire host of nations involved, there were a total of 241,400 men, 200 being reckoned for each ship. On board all these ships were 30 fighting men of the Persians and Medes and Sakai in addition to the company which each had of native fighters; the number of this added contingent is 36,210.\n\n > To this and to the first number I add the crews of the pentekonters, calculating 80 men for each, whether there were actually more or fewer. Now seeing that, as has already been said, 3,000 of these vessels were assembled, the number of men in them must have been 240,000.\n\n > These, then, were the ships' companies from Asia, and the total number of them was 517,610. There were 1,700,000 footsoldiers and 80,000 cavalrymen; to these I add the Arabian camel-riders and Libyan charioteers, estimating them to have been 20,000 in number. \n\n > The forces of sea and land added together would consist of 2,317,610 men. So far I have spoken of the force which came from Asia itself, without the train of servants which followed it and the crews of the grain ships.\n\n > I must, however, also take into account the force brought from Europe, and I will rely on my best judgment in doing so. The Greeks of Thrace and the islands off Thrace furnished 120 ships, and the companies of these ships must then have consisted of 24,000 men. As regards the land army supplied by all the nations—Thracians, Paionians, Eiordoi, Bottiaiai, Chalkidians, Brygoi, Pierians, Macedonians, Perrhaiboi, Enienes, Dolopes, Magnesians, Achaians, dwellers on the coast of Thrace—of all these I suppose the number to have been 300,000.\n\n > When these numbers are added to the numbers from Asia, the sum total of fighting men is 2,641,610.\n\n > As for the service train which followed them and the crews of the grain ships and all the other vessels besides which came by sea with the force, these I believe to have been not fewer but more than the fighting men. Suppose, however, that they were equal in number, neither more nor fewer. If they were equal to the fighting contingent, they made up as many tens of thousands as the others. The number, then, of those whom Xerxes son of Darius led as far as the Sepiad headland and Thermopylai was 5,283,220.\n\nThere are obviously a lot of rough-and-ready estimates here. Nevertheless, the thing to take away from the passage is that Herodotos was not content simply to throw a large number out there. Instead, he meticulously went through each contingent of the combined force, ascertaining the number of its ships and men, hedging his estimates, and using standard multiplication tables where applicable. He spells all this out to forestall any accusation that he was fudging his totals. Anyone who wishes to question Herodotos cannot just laugh at the final number, but must engage with this breakdown and show where the errors are. What is more, the first critic of Herodotos' totals was none other than *Herodotos himself* (7.187):\n\n > I do, however, wonder how there were provisions sufficient for so many tens of thousands, for calculation shows me, that if each man received one *choinix* of wheat a day and no more, 1,100,340 bushels would be required every day. In this calculation I take no account of the provisions for the women, eunuchs, beasts of burden and dogs.\n\nThis is not \"asspulling\". This is conscientious and critical evaluation of the results of empirical observation and mathematical calculation. This is, in a word, *science.* Recent work by Rosalind Thomas has shown Herodotos' debt to the medical authors of Ionian natural philosophy; he was raised in the methods of the earliest Greek \"scientists\" and valued descriptions of reality that were based on verifiable fact.\n\nBut then how did he end up with numbers that are incredible and cannot be right?\n\nHere we get beyond what these numbers *are* and into the arguably more interesting question what these numbers *do*. For Herodotos, it was not possible to get at the exact figure even for the Greek armies that fought in the Persian Wars; round figures were known for hoplites, but the historian was forced to carry out similar mathematical gymnastics to get at the number of light troops on the Greek side, since these were rarely officially counted. Greater exactitude than that displayed by Herodotos cannot really be expected. However, what he *did* know when he was writing his work was what the numbers were supposed to reflect. They were an expression of the full might of the Persian Empire - the largest empire the world had ever seen. They indicated the size of a display army raised to justify Xerxes' ascension to the throne; Xerxes had a personal interest in proving that this army was as large as possible. They were also a necessary element of a story in which the Greeks, with the help of the gods, won a victory that no rational observer would have thought possible.\n\nWhen we go beyond the Persian army numbers as facts and consider them as elements in Herodotos' story, it becomes much easier to understand why they are so stupendously large. As far as Herodotos was concerned, the Persians mobilised the entire empire against Greece, and he therefore set about calculating and estimating the combined forces of every single region within that empire, adding all of it together just before it hits Leonidas at Thermopylai. Both the historical Xerxes and the villain Xerxes from Herodotos' *Histories* were personally interested in proving the sheer size of their army to the world, and to the Greeks in particular. Meanwhile, to put the decisions of the Greeks in the right perspective - both those who resisted and those who chose to submit - it was necessary for Herodotos to highlight that what they faced was truly an enemy of superlative, incomprehensible strength. Only then would every part of his story - from his extensive survey of the Persian empire, to the character of the king, to the narrative of the resistance and eventual Greek victory - click together. Would any of this have made sense if Herodotos had admitted that the Persian army was probably just 150,000 strong at its height? Would the Persians have launched their invasion with a force barely larger than the Greek alliance that fought them at Plataia, and if so, would any Greek have submitted to that force?\n\nHerodotos' calculations and doubts show that he knew exactly what he was doing when he came up with these numbers. It was as far away from an ass pull as the Greeks could conceive of an army number to be. Herodotos was not making up numbers; he was trapped in a situation where one form of scientific observation and reasoning clashed with another, and he chose the solution that left his narrative intact."
]
}
|
[] |
[] |
[
[]
] |
|
1fcsz3
|
why does my stomach feel cold to the touch after a run or jog?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1fcsz3/elif_why_does_my_stomach_feel_cold_to_the_touch/
|
{
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"ca903t8"
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"text": [
"When you run or jpg your body is focusing on areas of your body that need more blood than your torso, as it isn't focusing on digestion so more blood is pumped elsewhere. Your heart, and lungs, and leg muscles need more blood when running, so your body is doing it's job by moving the blood from less important areas.\n\nYour body is also regulating it's internal temperature, heat is a byproduct of your cellular system at work. They are working hardest in the muscles in your legs that are being worked out during the run or jog. So the blood is redirected and moved to the surface in your legs to radiate the heat faster."
]
}
|
[] |
[] |
[
[]
] |
||
4ahndt
|
why do digital computer games cost the same or sometimes more than physical copies?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4ahndt/eli5_why_do_digital_computer_games_cost_the_same/
|
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"The expense of the disc and art is relatively minor. Keeping brick and mortar stores happy by not massively undercutting them is also a thing.",
"Two reasons:\n\n1) Barring special items like figurines or 3D cases, the cost of the physical goods is relatively insignificant. Even without the economies of scale available to a company you can get a case, CD, some paper and the most expensive part, ink for less than $2 a package.\n\n2) Maintaining physical inventory is significantly more expensive than a list of codes. The games take up space that could otherwise be used for a better selling item (as opposed to digital keys which take up maybe a few byes of data each), as well as paying for environmental controls so they don't grow mold or something like that. Sometimes businesses decide it is in their best interest to take a small loss in the short run, so they can stock a better selling product making more money in the long run.",
"The Physical stores is where you reach out to the beginner customers, they don't just decide to go online to buy their first game. If the game companies start competing with their own distributors by putting lower online prices they are only biting their own tail. In the short run they may earn more, but as more and more physical stores start closing down because they can't compete with the online pricing game producers will have difficulties reaching out to new customers.\n\nThey much prefer to keep the physical market alive and rake in a huge margin (basically 100% profit, while from a physical store, the store probably takes 50% and with some costs they are well below 50% themselves) on the few people who thinks it's more convenient to buy a digital copy for the same price because the physical one is just a dust collector for them.",
"The digital distribution service usually takes 30%. Physical distribution costs a bit more, but not so much.",
"A dvd costs like $.40 to make and burn. So, the cost is in the software, not the materials.",
"Because in the end your really just paying for the programming. The disc, case, cover are just the cost of doing business and all cheap to produce. In the end the there worth what people are willing to pay for them, and people are willing to part the same for digital and physical.",
"The price of most anything is based less on the actual cost of production and more on the price people will actually pay. Whatever a consumer is willing to pay to maximize profits, that is the price of the item. ",
"You're paying for the software, not the cases, discs, etc. Those cost the publishers maybe a dollar per copy to produce. So even if they were to pass the savings to the consumer, you'd only be saving a dollar at most."
]
}
|
[] |
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[
[],
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||
70v4bg
|
how can some people allegedly survive years without any food?
|
And how is it physically possible?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/70v4bg/eli5how_can_some_people_allegedly_survive_years/
|
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"It isn't possible, your body can't even survive 4 days without water. Why would they be any different?",
"Short answer: they can't.\n\nLong answer: they can't, but they claim they can and either secretly sneak food when no one is looking, or eat something (like fruit smoothies with protein powder in it) that they declare isn't \"food\" but something else (\"a drink\", \"medicine\", etc).",
"Literally without *any* food (but with water) you die from scurvy or similar malnutrition ailments within a month or 2.\n\nThere have been morbidly obese individuals that survived more than a year on water, vitamin supliments (to fend of scurvy), and small amounts of baker's yeast while under medical supervision. This is basically a 0 calorie diet, but does involve *some* food intake.\n\nThey were able to survive that long because their excess fat was used as a source of calories to keep them alive over that time.\n\nThis kind of crash diet is also incredibly unhealthy, BTW.",
"No person who has claimed to be able to survive without food and water has actually demonstrated it. Those who did attempt to demonstrate surviving without food or water were caught cheating (sneaking out of the test settings to get fast food, for instance)\n\nIn ideal circumstances(eg: decent humidity, and minimal physical activity), the human body can survive about a week without water, and about a month without food- at those points, your body runs out of water for important processes, and has been damaging your body by breaking it down for energy."
]
}
|
[] |
[] |
[
[],
[],
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] |
|
2wv0e9
|
measuring computing speed - what's the difference between flops, ips, hertz, cps, and the other cps?
|
Are any of these synonymous or convertible? Or are they all completely different and unrelated ways of measuring a computer's speed?
- FLOPS
- IPS
- Hertz
- [CPS (Calculations per second)](_URL_1_)
- [CPS (Computations per second)](_URL_0_)
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2wv0e9/eli5_measuring_computing_speed_whats_the/
|
{
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"text": [
"FLOPS is FLoating-point Operations Per Second.\n\nFloating point operations are more difficult than integer operations.\n\nIPS is \"instructions per second\". (A floating-point operation may require multiple instructions.)\n\nHertz is just the clock speed. Typically a computer can execute 1 operation per clock cycle, but some instructions take longer.\n\nCPS - I'm not sure if there's a difference between calculations and computations per second. I think they're the same. However, some instructions do multiple calculations. (Example: \"madd\" instructions do a multiply and an add). Also, SIMD processors (like the ones in your graphics card, but most CPUs have a SIMD processor as well, now) will do \"vectorised\" instructions, which means doing many (typically 4) instructions at the same time: 4 adds, or 4 multiplies, to different data. This will do 4 calculations, but with 1 instruction.\n\nTypically all these numbers will be fairly close to each other, but they're not exactly the same.\n\nActual numbers that you can measure will depend on which processor you're using (although not that much: different CPUs are pretty comparable - you'll see big differences between a GPU and a CPU, though), what you're doing with it, and how well the code was written, but the numbers given are usually best-case.",
"**FLOPS = Floating point operations per second** \nFloating point is a way of storing № which compromises between efficiency and accuracy (on computers). Operations refers to the mathematical operation.\n\n\n**Hertz (Hz) = Cycles/Second** \nThis is a measure of frequency (how fast something happens in a given time). It can be used to measure anything from your pulse (rarely if ever used) to the frequency of sound.\n\n**IPS = Instructions per second** \nThis is a measure of how many instructions can be executed per second. This measure can vary based on the instruction being tested or other factors.\n\n**Calculations per second** (Almost) Equivalent to FLOPS \n**Computations per second** Equivalent to IPS\n",
"FLOPS, or floating point operations per second, are used to measure the \"speed\" of a supercomputer used for scientific or engineering number crunching.\n\nMIPS, or millions of instructions per second, are used to measure the \"speed\" of a mainframe computer used for bulk data processing like updating the inventory of retail stores across the country at midnight. IPS would be a smaller unit of MIPS.\n\nHertz is the unit of frequency, which represents the number of cycles within a given time, usually 1 second. In USA, line voltage is 60Hz AC, which means that the voltage flips back and fourth between positive and negative 60 times every second.\n\nCalculations per second and Computations per second are a little harder to explain given the architecture of modern processors and computers. Calculations per second show individual mathematical operations per second. Computations per second is a bit harder to explain as several calculations or just one calculation can represent a computation, so it is application specific.\n\n"
]
}
|
[] |
[
"http://ourworldindata.org/data/technology-and-infrastructure/moores-law-other-laws-of-exponential-technological-progress/#note-5",
"http://trace.wisc.edu/tech-overview/wp-content/uploads/2007/01/exponentialgrowthofcomputingthumbnail.jpg"
] |
[
[],
[],
[]
] |
|
a032us
|
why does cold kill plants?
|
Why does cold kill plants (biologically), and us to a certain extent? What about the cold makes it unsuitable for life?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/a032us/eli5_why_does_cold_kill_plants/
|
{
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"eae5jzu"
],
"score": [
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"text": [
"It literally destroys cells. Cell membranes contain water, if the water in the cell membrane freezes then the cell membrane ruptures, destroying the cells."
]
}
|
[] |
[] |
[
[]
] |
|
a7bdxx
|
why have birth rates been declining since the "baby boom" of the 1950s ?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/a7bdxx/eli5_why_have_birth_rates_been_declining_since/
|
{
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"text": [
"The baby boom is directly attributable to soldiers coming back from World War II and starting families. This was helped by laws in the US that encouraged soldiers to buy homes. So, the birth rate was artificially high during the baby boom.\n\nIn general, however, birth rate has been declining in developed nations for at least 150 years. As medicine and standard of living have improved there is a much higher chance of your kids surviving to adulthood. There's no longer a need for a family to have 5 kids in order to ensure that some of them live to be adults. It makes more sense to have fewer kids and invest more into them so that they have the best possible advantages.",
"Easier access to contraceptives, sex education, and abortion.\n\nWomen going to college, choosing careers, essentially starting later in life- and then continuing on to have fewer babies. If you start your family at 30 instead of 18, you probably are not going to have 5+ kids. And you probably can't afford to stay home to raise them, either.\n\nCost. It's expensive to have multiple babies, so a typical household apart from religious (drop in religiosity being another factor) or cultural reasons make a conscious choice to have fewer or no children. Also a typical household is going to have two working parents, and child care costs aren't cheap. This also ties into some of the more recent generations wanting less of a traditional lifestyle- having none or one kid to make moving place to place/travelling easier.",
"rising cost of living and health care costs in the US are a big part of it. people just dont have the money to have 3+ children anymore. even the ultra rich stick to like 2-3 or less. people that are poor and live in poor areas might have larger sets of kids though, that can be attributed to lack of contraception or education"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
2rqwnx
|
why do radical muslims feel the need to avenge "offensive" depictions of their prophet? couldn't allah and muhammad dispatch the guilty themselves?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2rqwnx/eli5_why_do_radical_muslims_feel_the_need_to/
|
{
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"text": [
"They see themselves as vessels for god's punishment.",
"Question has been answered, but I feel I should point out that to my knowledge Muslims don't believe Mohammed intervenes in the world today. I think they'd consider that notion borderline idolatry or polytheism, and Islam places a *very* strong emphasis on worshipping Allah and *only* Allah. That's why images are prohibited in the first place.",
"Allah is pretend, so he can't do anything himself. Deep down Muslims know this. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
6e8tre
|
how did germophobes deal with germs pre-1800s?
|
How did they cope with dirt and grime? Tossing fecal matter in the streets? I know they had no solid concept of germs til the 1860s with Louis Pasteur, but how did they cope with the anxiety? I know that survival took precedence, but I wondered how I,( a germophobe) would cope with it in the hunter-gatherer days, medieval times, 1700s, etc?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6e8tre/eli5_how_did_germophobes_deal_with_germs_pre1800s/
|
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"text": [
"You can't be phobic of something you're not even aware of... in the same way that no one at that time had anxiety around flying in an airplane. \n\nThere were \"neat freaks,\" but they wouldn't have thought in terms of germs or disease, just dirt and cleanliness.",
"The more medical term is mysophobia, the fear of uncleanliness. Before the discovery of germs, this condition no doubt existed and sufferers would have had a pathological fear of dirt and contamination, but it wasn't identified as a condition until 1879.\n\nThe man who identified it was actually investigating cases of OCD that manifested itself as the compulsion to repeatedly wash hands, so mysophobes -- just as today -- would have wanted to avoid any dirt (real or imagined) and wash it off themselves.",
"In all probability, there weren't any \"germophobes\" back then. Science, especially microbiology wasn't as advanced as it is today. Germs weren't perceived as a legible threat because no one knew much about them."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
331mdv
|
why xbox live, psn fall prey to a handful of hackers while facebook, amazon seem airtight?
|
A small DDoS group takes down PSN and Xbox Live pretty much whenever they want, while other places like Netflix, Facebook and Amazon are immune. Is it a matter of the gaming services being too cheap to increase security?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/331mdv/eli5_why_xbox_live_psn_fall_prey_to_a_handful_of/
|
{
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"text": [
"You can't prevent a DDoS attack, you can only increase the required size of the attack to something that is not feasible. Given a large enough botnet, you would be able to take all of these services down.\n\nIt's simply far easier to expand web services because a client can connect to any server at any time. If you load amazon you might be connecting to a server in the UK, suddenly the UK server is taken down by a DDoS attack, but this doesn't matter until you click to view a product at which point you download that page from a server in France. As the user, you wouldn't notice anything.\n\nA game requires real time responses from the server. If a web page takes 2 seconds to load you may not even notice, a game would become completely unplayable. It also requires multiple users to be connected to the same server as the code executed on the server is managing the communications between these clients. You can't just route to a different server for every request.\n\nBasically the nature of game servers make them significantly more vulnerable to this type of attack than web servers. "
]
}
|
[] |
[] |
[
[]
] |
|
m1gch
|
How far down can you sink an egg in water before it cracks?
|
askscience
|
http://www.reddit.com/r/askscience/comments/m1gch/how_far_down_can_you_sink_an_egg_in_water_before/
|
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"15.2 MPa is the fracture strength of an egg as reported here, _URL_0_\n\n1 MPa corresponds to 101 m of water column depth. So you could sink it approximately 1500 m before it fractures.\n\nedit: As others have pointed out, the study specifically mentions internal pressure, not external pressure. I'm looking to see if I can find an estimate for external pressure induced failure.",
"The answer is, \"it depends, but possibly so deep that it could never happen on Earth, for a perfect egg\". If the egg is filled with a Newtonian fluid, then it can't be crushed under [hydrostatic loading](_URL_0_). \"Hydrostatic loading\" means that the pressure on the egg is due only to gravity exerting a force on the fluid it's in (and not, say, somebody crushing the egg in their hand).\n\nLet's say that the egg is stationary in the water. Then it's at equilibrium with the forces of pressure surrounding it: the pressure is equal on all sides. If it weren't equal, then the egg would accelerate in some direction since there would be a net force.\n\nIf we want to move the fluid around in the egg, it needs to somewhere to go -- a path of least resistance. But the fluid inside the egg is contained, and is being pushed on from all sides evenly, so it has nowhere to go. So it withstands the force being applied to it from the seawater pressure by pushing back with an equal force. The eggshell in the middle is thus compressed uniformly.\n\nSince the egg is stationary and it's being pushed on from all sides with a perpendicular force, we'll need an unbalanced force to crush it. That means that if we want to crush it, there must be a force in one direction on the egg that is not balanced by a force on the opposite side. That's why you can crush an egg by lightly tapping it against a glass bowl in your kitchen -- you applied a nonuniform force to the surface of the egg that it can't distribute effectively. Conversely, it's much, much harder to crush an egg by using only your thumb and forefinger on the top and bottom (although that isn't really a demonstration of hydrostatics).\n\nOne way to get the perfect egg to crack would be to submerge it in water on a fictitious, unusually-shaped planet where the gravity was highly variable over short (egg-length) distances. In this case, the pressure exerted from one direction would be different than another, and gravity would pull with different forces on the surface of the egg. In essence, you would be ripping the egg apart by tidal forces, rather than crushing it with water, which is perhaps cheating.\n\nOf course, even the slightest imperfection or air pocket (like those found in real eggs) would eventually destroy it under some kind of pressure, in which case you'll want to consult [this fine answer](_URL_1_).",
"Eggs take an average of 15.2 MPa to crack from outside pressure. (_URL_0_)\n\nThe equation for pressure on an object submerged in fluid is pressure = density x depth x gravity. This means that the depth you'd need to get an egg in order for it to crack under pressure is 15.2 MPa/((9.81m/s^2)*(1 g/cm^3). This reduced is 1549.44 meters, or a little less than a mile under water.\n\nTLDR: Eggs are pretty tough.",
"How high up can you bring an egg before it explodes?",
"Hydrostatic pressure is isotropic and has no shear component. Thus for solid objects no permanent deformation will take place, rather just isotropic elastic contraction.\n\nThe calculation would require 1) the compressive failure stress of an egg shell 2) the elastic modulus of the shell 3) the elastic modulus of the egg contents. The answer will also vary with the egg volume, shell thickness, and of course defect density. Clearly simplifications are needed to make some progress.\n\nApproximating the egg as a rock, it will never crack under hydrostatic pressure.",
"Follow-up question, does it matter how the egg is oriented in the water?",
"Isn't the shell of an egg permeable, as to allow pressure to equilibrate?",
"You can [calculate this yourself based on the compressive strength of eggshells.](_URL_1_).\n\nEdit: similar exercise [here](_URL_0_) claims that one experiment resulted in an egg supporting 200 pounds.",
"Okay, everyone here has been avoiding the physics... come on, guys! You have to consider the isothermal compressibility of the shell, the albumin, and the yolk! If they're all the same, then the egg *will not crack under hydrostatic pressure.* However, they are not the same, since the shell is made out of calcite, and the albumin and yolk are made out of other stuff. I found [an article](_URL_0_) dealing with the situation in which an egg is heated and cracks as a result, but I haven't been able to locate one that deals with isothermal compressibility. If someone can find that, the question will be answered.\n\nWithout the numbers, this is not too hard to measure... It doesn't matter (much) that it's water and not air, so someone could put an egg in a pressure chamber. Anyone have access?\n\nedit: spelling",
"As a scuba diver we take eggs down to 30 meters all the time. At that pressure you can remove the shell and the raw egg will stay perfectly intact and be neutrally buoyant. It a neat little trick, but I'd implode long before an egg would if I had to dive deep enough to get an egg to crack. \n\nYou can also drink out of an open soda can from that depth. The pressure keeps the coke inside the can ",
"Materials Engineer here: The egg shouldn't crack at all. When you completely submerge the egg in water the egg is experiencing hydrostatic pressure, meaning equal pressure from all sides. Assuming the egg is incompressible (the only part of this I'm really not sure about), then all of the pressure will have opposing pressures cancel each other out, resulting in the egg staying in tact. If it is not incompressible then it can crack, but that calculation would involve bulk modulus (G) of the egg shell instead of youngs modulus (E) which has come up in a few discussions here.",
"I'll let you know.\n\nWould you prefer a brown egg?",
"I had relatively long discussion about this with some friends of mine. Considering that no one was able to provide a compelling argument we decided to test it; FOR SCIENCE! Fortunately we were on the Corwith Cramer SSV and about to be on station for a 1600m styrocast. The egg (along with the Styrofoam cups) was lowered to 1600m at a rate of 50m/min and subsequently recovered with no discernible damage. \nThe styrocast was on July 3 2011.\n[Link to the blog of the cruise.](_URL_0_)\n\n**TL;DR** I can personally confirm that 1600m of salt water is not sufficient to crack an egg.\n\n",
"I learned a neat trick on Reddit today! You can tell the colour of an egg based on the diver ear lobe.",
"15.2 MPa is the fracture strength of an egg as reported here, _URL_0_\n\n1 MPa corresponds to 101 m of water column depth. So you could sink it approximately 1500 m before it fractures.\n\nedit: As others have pointed out, the study specifically mentions internal pressure, not external pressure. I'm looking to see if I can find an estimate for external pressure induced failure.",
"The answer is, \"it depends, but possibly so deep that it could never happen on Earth, for a perfect egg\". If the egg is filled with a Newtonian fluid, then it can't be crushed under [hydrostatic loading](_URL_0_). \"Hydrostatic loading\" means that the pressure on the egg is due only to gravity exerting a force on the fluid it's in (and not, say, somebody crushing the egg in their hand).\n\nLet's say that the egg is stationary in the water. Then it's at equilibrium with the forces of pressure surrounding it: the pressure is equal on all sides. If it weren't equal, then the egg would accelerate in some direction since there would be a net force.\n\nIf we want to move the fluid around in the egg, it needs to somewhere to go -- a path of least resistance. But the fluid inside the egg is contained, and is being pushed on from all sides evenly, so it has nowhere to go. So it withstands the force being applied to it from the seawater pressure by pushing back with an equal force. The eggshell in the middle is thus compressed uniformly.\n\nSince the egg is stationary and it's being pushed on from all sides with a perpendicular force, we'll need an unbalanced force to crush it. That means that if we want to crush it, there must be a force in one direction on the egg that is not balanced by a force on the opposite side. That's why you can crush an egg by lightly tapping it against a glass bowl in your kitchen -- you applied a nonuniform force to the surface of the egg that it can't distribute effectively. Conversely, it's much, much harder to crush an egg by using only your thumb and forefinger on the top and bottom (although that isn't really a demonstration of hydrostatics).\n\nOne way to get the perfect egg to crack would be to submerge it in water on a fictitious, unusually-shaped planet where the gravity was highly variable over short (egg-length) distances. In this case, the pressure exerted from one direction would be different than another, and gravity would pull with different forces on the surface of the egg. In essence, you would be ripping the egg apart by tidal forces, rather than crushing it with water, which is perhaps cheating.\n\nOf course, even the slightest imperfection or air pocket (like those found in real eggs) would eventually destroy it under some kind of pressure, in which case you'll want to consult [this fine answer](_URL_1_).",
"Eggs take an average of 15.2 MPa to crack from outside pressure. (_URL_0_)\n\nThe equation for pressure on an object submerged in fluid is pressure = density x depth x gravity. This means that the depth you'd need to get an egg in order for it to crack under pressure is 15.2 MPa/((9.81m/s^2)*(1 g/cm^3). This reduced is 1549.44 meters, or a little less than a mile under water.\n\nTLDR: Eggs are pretty tough.",
"How high up can you bring an egg before it explodes?",
"Hydrostatic pressure is isotropic and has no shear component. Thus for solid objects no permanent deformation will take place, rather just isotropic elastic contraction.\n\nThe calculation would require 1) the compressive failure stress of an egg shell 2) the elastic modulus of the shell 3) the elastic modulus of the egg contents. The answer will also vary with the egg volume, shell thickness, and of course defect density. Clearly simplifications are needed to make some progress.\n\nApproximating the egg as a rock, it will never crack under hydrostatic pressure.",
"Follow-up question, does it matter how the egg is oriented in the water?",
"Isn't the shell of an egg permeable, as to allow pressure to equilibrate?",
"You can [calculate this yourself based on the compressive strength of eggshells.](_URL_1_).\n\nEdit: similar exercise [here](_URL_0_) claims that one experiment resulted in an egg supporting 200 pounds.",
"Okay, everyone here has been avoiding the physics... come on, guys! You have to consider the isothermal compressibility of the shell, the albumin, and the yolk! If they're all the same, then the egg *will not crack under hydrostatic pressure.* However, they are not the same, since the shell is made out of calcite, and the albumin and yolk are made out of other stuff. I found [an article](_URL_0_) dealing with the situation in which an egg is heated and cracks as a result, but I haven't been able to locate one that deals with isothermal compressibility. If someone can find that, the question will be answered.\n\nWithout the numbers, this is not too hard to measure... It doesn't matter (much) that it's water and not air, so someone could put an egg in a pressure chamber. Anyone have access?\n\nedit: spelling",
"As a scuba diver we take eggs down to 30 meters all the time. At that pressure you can remove the shell and the raw egg will stay perfectly intact and be neutrally buoyant. It a neat little trick, but I'd implode long before an egg would if I had to dive deep enough to get an egg to crack. \n\nYou can also drink out of an open soda can from that depth. The pressure keeps the coke inside the can ",
"Materials Engineer here: The egg shouldn't crack at all. When you completely submerge the egg in water the egg is experiencing hydrostatic pressure, meaning equal pressure from all sides. Assuming the egg is incompressible (the only part of this I'm really not sure about), then all of the pressure will have opposing pressures cancel each other out, resulting in the egg staying in tact. If it is not incompressible then it can crack, but that calculation would involve bulk modulus (G) of the egg shell instead of youngs modulus (E) which has come up in a few discussions here.",
"I'll let you know.\n\nWould you prefer a brown egg?",
"I had relatively long discussion about this with some friends of mine. Considering that no one was able to provide a compelling argument we decided to test it; FOR SCIENCE! Fortunately we were on the Corwith Cramer SSV and about to be on station for a 1600m styrocast. The egg (along with the Styrofoam cups) was lowered to 1600m at a rate of 50m/min and subsequently recovered with no discernible damage. \nThe styrocast was on July 3 2011.\n[Link to the blog of the cruise.](_URL_0_)\n\n**TL;DR** I can personally confirm that 1600m of salt water is not sufficient to crack an egg.\n\n",
"I learned a neat trick on Reddit today! You can tell the colour of an egg based on the diver ear lobe."
]
}
|
[] |
[] |
[
[
"http://rspb.royalsocietypublishing.org/content/263/1369/433.short"
],
[
"http://en.wikipedia.org/wiki/Fluid_statics#Hydrostatic_pressure",
"http://www.reddit.com/r/askscience/comments/m1gch/how_far_down_can_you_sink_an_egg_in_water_before/c2xawec"
],
[
"http://rspb.royalsocietypublishing.org/content/263/1369/433.short"
],
[],
[],
[],
[],
[
"http://www.csun.edu/~mk411573/discrepant/discrepant_event.html",
"http://www.sciencebuddies.org/science-fair-projects/project_ideas/MatlSci_p021.shtml"
],
[
"http://www.math.cornell.edu/~rand/randpdf/eggshell.pdf"
],
[],
[],
[],
[
"http://www.sea.edu/voyages/blog_cramer_235a"
],
[],
[
"http://rspb.royalsocietypublishing.org/content/263/1369/433.short"
],
[
"http://en.wikipedia.org/wiki/Fluid_statics#Hydrostatic_pressure",
"http://www.reddit.com/r/askscience/comments/m1gch/how_far_down_can_you_sink_an_egg_in_water_before/c2xawec"
],
[
"http://rspb.royalsocietypublishing.org/content/263/1369/433.short"
],
[],
[],
[],
[],
[
"http://www.csun.edu/~mk411573/discrepant/discrepant_event.html",
"http://www.sciencebuddies.org/science-fair-projects/project_ideas/MatlSci_p021.shtml"
],
[
"http://www.math.cornell.edu/~rand/randpdf/eggshell.pdf"
],
[],
[],
[],
[
"http://www.sea.edu/voyages/blog_cramer_235a"
],
[]
] |
||
3lxnrk
|
Tuesday Trivia | Autumn Holidays, Observances, and Festivals
|
[Previous weeks' Tuesday Trivias and the complete upcoming schedule.](_URL_0_)
Tomorrow’s the first day of fall! And so let’s talk about **fall holidays, including harvest observances,** in whatever culture and time period you’d like.
**Next week on Tuesday Trivia:** keeping up with current interest in mass human migrations and refugees, the theme will be Movements and Migrations.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3lxnrk/tuesday_trivia_autumn_holidays_observances_and/
|
{
"a_id": [
"cva653r"
],
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"text": [
"Most opera houses and companies today run on a \"season\" schedule which runs from Fall through Spring, with summer off. This Monday was the opening of the [Met season with fancy dresses etc.](_URL_0_) The season is a very long standing tradition in opera, one of the older traditions to survive. \n\nThe first opera \"seasons\" in 17th century Venice were much much shorter, running just the gamut of Carnival and stopping abruptly at Lent, when such frivolities as theater were no longer appropriate. As opera spread through Italy, seasons started pushing back further and further into the winter (but with a stop for Advent) and then fall but not into summer. Try to imagine what a fire-trap opera house was like in the dead of summer, and you'd not want to go to the opera either. They also often split the season around Advent, so you'd have a fall season, which was the \"smaller\" season, and the Carnival season, which was the bigger one. Some bigger singers would work each half season in a different city, Carnival being the more lucrative season you could demand more cash for. But they had to keep that Lenten cut-off for quite a while, despite opera still being desired by customers in the late winter-early spring. However, as a rather clever workaround during periods of normal opera being verboten, there is a small genre called Lenten Opera, which are religious operas that tell Bible stories. One of the few examples you'll catch on a modern stage is Rossini's *Mose in Egitto.* \n\nToday the traditional opera season is no longer as cemented with the summer doldrums, for one, air conditioning makes sitting in a theater in August a lot more attractive, but to opera buffs, Fall still means Finally It's Opera Time Again. The opera season's nice line-up with the traditional school calendar in the West is also a boon to music schools at universities, who can run their student operas right on tradition. "
]
}
|
[] |
[
"http://www.reddit.com/r/AskHistorians/wiki/features/trivia"
] |
[
[
"http://www.wqxr.org/#!/story/photos-met-opera-season-opens-red-carpet-times-square-simulcast/"
]
] |
|
40lszi
|
why is the canadian dollar falling so low?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/40lszi/eli5_why_is_the_canadian_dollar_falling_so_low/
|
{
"a_id": [
"cyv5r6m",
"cyvkz27"
],
"score": [
20,
2
],
"text": [
"Because our economy was too dependent on oil being $100+ a barrel, and because as the American economy recovers from the 2008 financial crisis their dollar will strengthen, so ours by comparison has to weaken. ",
"The CAD - > USD is dropping mainly due to the USD strength. The US dollar is very strong, and continues to outperform the world currencies. The CAD - > AUS and CAD - > EUR hasn't changed that much. The US has (and may continue) to raise interest rates which will only make it stronger. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
8q1vlz
|
what's going in inside of your stomach when you haven't gone to the toilet for ages?
|
*Using myself only as an example, this isn't a personal/medical help question*
I haven't gone to the toilet for the past 4 days now (completely normal for me (IBS)) but what happens to all the food I've eaten in those 4 days? I've had 4x3=12 normal sized meals, so where does all that food go? I can't imagine that it all sits in your stomach or else it would burst?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8q1vlz/eli5_whats_going_in_inside_of_your_stomach_when/
|
{
"a_id": [
"e0frud0",
"e0fs1ys"
],
"score": [
7,
4
],
"text": [
"The waste is building up in your intestines, but if you have eaten low-fiber food, it may be surprisingly little waste — the fluids and nutrients having been absorbed into your body through the intestinal walls.",
"Not in your stomach, no. It sits in your large intestine, devoid of any nutrients and moisture. If you have eaten foods that do not ferment then it doesn't do much, however if you've eaten a lot of indigestable fiber it will bloat your bowels and bring every unpleasant feeling associated with that."
]
}
|
[] |
[] |
[
[],
[]
] |
|
zqd1u
|
Can someone explain what happened to Jupiter yesterday? (Video of impact/crash in description)
|
askscience
|
http://www.reddit.com/r/askscience/comments/zqd1u/can_someone_explain_what_happened_to_jupiter/
|
{
"a_id": [
"c66uok0"
],
"score": [
2
],
"text": [
"Looks like a light artefact to me. "
]
}
|
[] |
[] |
[
[]
] |
||
35szs5
|
Why weren't Portugal or Netherlands muscled out by the larger powers?
|
During the age of discovery and the time of colonialism why didn't larger powers just blockade the dutch or Portuguese in Europe then pick off there colonies? By Larger powers I do mean nations like Great Britain, France and Spain
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/35szs5/why_werent_portugal_or_netherlands_muscled_out_by/
|
{
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"text": [
"I can't answer for Portugal, but in the case of the Netherlands: they tried. *Oh they tried*. Here's a quick list of wars:\n\n* 1568–1648 Eighty Year's War (vs Spain) - Dutch win\n* 1652–1654 First Anglo-Dutch War - Stalemate (advantage English)\n* 1665–1667 Second Anglo-Dutch War - Dutch win\n* 1672–1674 Third Anglo-Dutch War - Dutch win\n* 1672-1678 Franco-Dutch War - Dutch don't lose (after nearly being annihilated)\n* 1688 Glorious Revolution - Not really a war, but it did end with a Dutch guy on the English throne\n\n\nLet's place this list in a bit of context.\n\n\n**Eighty Year's War**\n\nThe Eighty Year's War (1568-1648) could be seen as the Dutch war of independence. But that would be too simple. Dutch independence was achieved *de facto* by 1609. In that year, after several years of negotiations, the Dutch and Spanish signed a truce for twelve years. This could have been a full-blown peace, but the Dutch didn't like Spanish demands regarding the colonies. The Spanish wanted the Dutch to guarantee that their ships would never sail south of the equator, basically requiring them to give up their colonies in the East. This was unacceptable. So the negotiations ended with a truce instead, set for 12 years, with no special provisions regarding trade or colonies. This proved to be somewhat of a mistake, and the truce only held in Europe. In the East as wel as in the Americas the Dutch and Spanish returned to competition by force even during the 12 years of the truce.\n\nAs the truce was coming to its end in 1621, the Dutch briefly contemplated extending it or even signing a peace. They didn't though. The period of the truce had been useful to build up the country and the economy, and now the Dutch felt strong. They were also still upset about the Spanish demands in the earlier negotiations. So ***the Dutch* opted to continue the war, as it would be hugely profitable for them** and would deny the Spaniards access to their northern ports (chiefly Antwerp, which the Dutch could easily blockade since they controlled the Scheldt estuary). The Spanish put up a decent fight, but by 1648 they had no choice but the accept full-blown Dutch independence, with no limitations on Dutch colonies or navigation.\n\n**Anglo-Dutch wars**\n\nAll this time England and France were quite happy to let the Dutch do their thing. They were happy the Dutch were chipping away at Spanish power. That changed though after 1648. The English especially thought the Dutch were taking over too much of their trade with the Americas. The English Navigation Acts of 1651 were intended to reestablish English dominance over the Atlantic trade. This led to a direct confrontation with the Dutch, and to the first of four Anglo-Dutch wars. The English were quite successful in this war, as the Dutch had decommissioned much of their army and navy after the end of the Eighty Year's War. The fighting exhausted both sides, and in 1654 a peace treaty was signed which did not solve the rivalry in trading. \n\nThe Second Anglo-Dutch War was provoked in 1665 by the English particularly to end the Dutch trading empire. Both sides had successes in this war, but the Dutch came out on top - not in small part thanks to a daring raid by Admiral de Ruyter. In 1667 De Ruyter sailed his fleet up the river Thames, broke the chains which guarded the Medway, and attacked the English naval base Chatham directly. Several English capital ships were sunk or captured in this raid, and many more other naval vessels were destroyed. After this, the English could no longer stay in the fight, and a peace treaty was signed. \n\nThe Third Anglo-Dutch War coincided with the Franco-Dutch War and with attacks from Cologne and Munster. **The Dutch Republic was attacked from *all sides* by English, French, and German forces.** On land, the Dutch were in quite a pickle (I'll cover the French part in a bit.), but on sea [the Dutch still outmatched anyone else](_URL_0_). The English fleet was trounced in *four* naval battles. In 1674 the English signed a seperate peace with the Dutch.\n\nI did mention a fourth Anglo-Dutch war but that was more than a century later and, as we will see, no longer relevant for your question.\n\n**Franco-Dutch War**\n\nAt the same time as the English were getting trounced on the sea, French forces had invaded the Dutch Republic from the south. And they were quite successful. A large part of the Republic fell to the French in one year. Only the large scale inundation of the countryside (the \"Dutch Water Line\") kept the French out of Holland (that is the province of Holland, the richest and most important province with cities such Amsterdam, Leiden, and Dordrecht). \n\nThe Dutch regents had neglected the army for many years, as they considered it too much of a money sink. They'd rather spend their money on trade and luxuries. Now it almost seemed the French were allowed to simply walk into the Republic. The people were dissatisfied, and took out their anger on two of the most important regents, killing them in an absolutely brutal and horrific way (see my description of that in a post [here](_URL_2_)). The regents had kept William III, Prince of Orange out of power for a couple of decades, but now the people welcomed Orange back. He was given command of the army, and started to recover the situation. 1672 is still called the \"Disaster Year\" by the Dutch, as the Republic was on the brink of destruction. \n\nIn 1673 the Dutch got assistance from the Holy Roman Emperor and from Spain (yes, *Spain*!). The goal of this large alliance was to reduce France to its pre-war borders. The rest of the war isn't that interesting, what's important here is that the Dutch Republic came out of this without losing any of its territory, and with a much stronger Prince of Orange. After being excluded from politics for two decades, he now was the saviour of the Republic.\n\n**Glorious Revolution**\n\nWilliam III of Orange married Mary Stuart, daughter of James Stuart, in 1677. In this way, William became involved in English politics. The catholic James was unpopular among English nobles, who invited the protestant William to come to England and seize the throne with his wife Mary. In november 1688 Dutch forces under the command of William landed in England. As English protestants rallied behind William, James gave up resistance. With this so-called \"Glorious Revolution\" William III became king of England. \n\nWilliam III was still stadtholder in the Dutch Republic, but that made him nothing more than a civil servant - granted, the most important civil servant, but a civil servant nonetheless. (For more on that, see my post [here](_URL_1_).) In England he was a proper King. With one man leading both the Dutch Republic and England, those countries would now act in unison. The Dutch Republic, having resisted England for so long and now even having some control over it, became the junior partner in this though. William III held his court in London and many dutch merchants and nobles flocked to London to be closer to him. The Dutch Republic started a long period of decline because of this. During the 18th century the Dutch Republic wasn't nearly as powerful as it was the previous century. Army and fortifications were neglected. In the later part of the 18th century the Dutch were soundly beaten by English forces in the Fourth Anglo-Dutch War and later still they were overrun by French revolutionary forces, ending the Dutch Republic.\n\n**Conclusion**\n\nSo in the end the Dutch weren't \"muscled out\" of anything. That was certainly tried, but all attempts had failed. No, it was an apparant Dutch success, the seizure of the English throne, which put an end to Dutch supremacy in trade.\n\n\n----------\nPublic notice: I was previously known as /u/edXcitizen87539319",
"Since you asked about both Portugal and the Netherlands, I'd like to add a bit of perspective to the answer by /u/Polybios . \n\n**Treaty of Tordesillas: Spain and Portugal**\n\nThe Treaty of Tordesillas of 1494 divided the world between Spain and Portugal. A North-South demarcation line was set up halfway between Portugal's Azores islands and Spain's claimed Cuba and Hispaniola. Spain was to control lands west of this line, and Portugal east of it. On the other end of the globe, the dispute was solved by the Treaty of Zaragoza of 1494. Effectively all this gave the Americas to Spain except for parts of Brazil to Portugal, in addition to giving the Philippines to Spain. It gave the east Indies (India, Indonesia, most of east Asia) to Portugal, along with ports in Africa.\nAs a result, the way trade was set up between those colonies and Spain/Portugal was that Spanish ships took westward trajectories across the Atlantic, and then across the Pacific to the Philippines. Portuguese ships went to Brazil or Africa and then to the Indian Ocean and up the east Asian coast as far as Japan.\n\n**Dutch Rebellion, Portugal Succession Crisis**\n\nSpain, or to be more precise the various possessions of Philip II and his descendants had various conflicts around the world, including against a Protestant England and a rebellious, Protestant Netherlands, starting from the mid 1500s and intensifying through the 1600s. While Spain's Army of Flanders was fighting the rebels in the Netherlands, traders from the Netherlands could still trade with Lisbon, thus they became aware of the sea routes to various Portuguese trading posts around the world.\n\nIn 1580, due to succession crises in Portugal, Spain's Philip II asserted his claim to the kingship of Portugal, thus setting Spain-Portugal under personal union. As he was at war against the Netherlands rebels and France, and eventually against England, these parties were no longer allowed to trade in Lisbon, and further they had incentive to attack Portuguese ships and posts around the world.\n\nBy that point Spain and Portugal had set up parallel trading routes with little overlap. Thus, while on the one hand Portugal now had access to sell goods to Spanish posts (including notably slave trade), Portugal was dragged into Spain's wars with little protection from Spain. In 1592 England captured a Portuguese fleet returning from Asia, thus setting the stage for England's own interest in the region.\n\nThe Dutch, previously partners in Portuguese development of sugar cane plantations in Brazil, attacked Portugal there to gain control of their own plantations. In Asia, they set up their own base in Batavia (today's Jakarta), then attacked Portugal's important posts in Angola, then in Goa, then in Japan.\n\n**Consolidation and Portugal's Restoration**\n\nBack in continental Europe, Spain's commitments in the Thirty Years War led to increased taxation in Portugal, and further enmity from belligerents in that conflict. Portuguese royals and merchants saw Spain as providing insufficient help even in Brazil, let alone Asia. Thus, they rebelled and this led to the Portuguese Restoration War. Even before the the restoration was complete, Portugal had started negotiations with England and Dutch that saw Portugal re-gain supremacy over Brazil and the Dutch over Indonesia.\nBy the time Spain recognized Portugal's independence in 1680, Portugal was already left with a much smaller empire, most of which losses were to a former ally (England) and a former economic partner (the Netherlands).\n\nSources:\n\n* J. H. Elliott, \"Imperial Spain: 1496-1716,\" ISBN-13: 978-0141007038, 2nd ed 2002. \n* J. H. Elliott, \"Spain, Europe and the Wider World: 1500-1800,\" ISBN-13: 978-0300145373, 2009. ",
"Since no one has mentioned it, my first response is that from before 1600 to 1800, the Netherlands had the highest GDP per capita in the world. So in that way, it was the largest power. I don't know exactly why it had such a high gdp, I'm sure arable land, moderate climate, and ease of irrigation (since the country is so flat) was important. My feeling is that The Netherlands was on its way to becoming an economic power before it became a Naval and sea-going trade power, and thus the internal economy generated the external strength. I'm sure the two must have developed together, but can we say which came first, economic power or naval power?",
"There was a balance of power. The great powers were fighting each other as well. Countries constantly switched sides. The French and English supported the Republic against Spain (80YRW), later the Spanish supported the Republic against France and England (Rampjaar) and finally the Republic and England fought France and Spain (Spanish Succession). The Holy Roman Empire, Portugal, the Pope, Sweden, Russia, etc. were all factors too at some point.\n\nEuropean powers fought for centuries and it took until Napoleon that \"blobification\" finally resulted in skewed sides. And even he was kept contained by the UK and Russia.\n\nAlso, colonies *were* lost. The Dutch took many Portugese colonies, and subsequently often lost them to England/the UK. New Netherlands (North America), New Holland/Zeeland (Australia/New Zeeland), South Africa and Ceylon/Sri Lanka are some examples. Formosa/Taiwan was also lost to Ming China at some point.\n\nIt should also be kept in mind that in the mid 1600s Portugal had about 1 million people, the Republic 1,5m, England 4m and France 20m. France was a powerhouse but England much less so."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/35szs5/why_werent_portugal_or_netherlands_muscled_out_by/cr7n8t5",
"https://www.reddit.com/r/AskHistorians/comments/2w9nur/after_the_close_ties_between_britain_and_the/cop5ol8",
"https://www.reddit.com/r/AskHistorians/comments/28tyll/how_did_the_murder_of_johan_and_cornelius_de_witt/cieuqvb"
],
[],
[],
[]
] |
|
3drsf2
|
Why were most carnivor dinosaurs bipedal?
|
In contrast to most herbivores, which appear to be 4-legged. Shouldn't 4 legs offer advantages like more speed (at least on short distances), more stability, and generally being more agile due to having 4 pivot points?
|
askscience
|
http://www.reddit.com/r/askscience/comments/3drsf2/why_were_most_carnivor_dinosaurs_bipedal/
|
{
"a_id": [
"ct8k7ai"
],
"score": [
3
],
"text": [
"All carnivorous dinosaurs that we know of were [theropods](_URL_0_), and all theropods had two legs.\n\nChanging diet (going from herbivore to carnivore or *vice-versa*) is a huge evolutionary change. We do know of some theropods who turned vegetarian (it's believed that the basal members of *theropoda* were all carnivores), but it seems to be a rare occurrence.\n\nAs for more agility, it's possible depending on the exact build. But conversely, bipedalism is more efficient energy wise. And dinosaurs often had long and heavy tails which could be used for balance when making sharp turns."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Theropoda"
]
] |
|
935932
|
why do tv stations still air new episodes at a set time, if it'll be on demand and streamable anyway?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/935932/eli5_why_do_tv_stations_still_air_new_episodes_at/
|
{
"a_id": [
"e3ao75e"
],
"score": [
6
],
"text": [
"The channels or stations that air new episodes have exclusive broadcast rights (that they pay the studio that makes the show) lots of money for. The channel/stations do this for advertising revenue - so for the two or three months between the show airing and when it shows up in iTunes or Netflix, the channel that broadcasts it gets to make money from the commercials they show during it. \n\nNot common, but sometimes a channel will take a loss on airing a new show to highlight their own shows that they'll put on immediately after. Like, CTV airing Game of Thrones season premiere and airing their new police procedural right after. "
]
}
|
[] |
[] |
[
[]
] |
|
75yiax
|
Is water's high specific heat capacity a property of the molecule itself, or an emergent property of many molecules?
|
askscience
|
https://www.reddit.com/r/askscience/comments/75yiax/is_waters_high_specific_heat_capacity_a_property/
|
{
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6
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"text": [
"*For gases*, the specific heat capacity at a given temperature is determined by the number of degrees of freedom available to each individual molecule. So it’s a property of the molecular structure.\n\nThis property of individual molecules determines the response of a macroscopic amount of them to changes in temperature (C = dE/dT).\n\nFor condensed matter, where intermolecular interactions are strong, the heat capacity can't be determined from the properties of individual molecules alone."
]
}
|
[] |
[] |
[
[]
] |
||
ytle1
|
What causes the body to slow bladder and bowel functions during sleep, and could this be artificially reproduced?
|
askscience
|
http://www.reddit.com/r/askscience/comments/ytle1/what_causes_the_body_to_slow_bladder_and_bowel/
|
{
"a_id": [
"c5yq70a"
],
"score": [
2
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"text": [
"Normally you produce more anti-diuretic hormone (ADH) at night, this decreases the need to pee. [Desmopressin](_URL_0_) acts like ADH. Peristalsis slows at night which is why you don't usually need to awaken to poo. Imodium or a cheese heavy diet can recreate that effect..."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Desmopressin"
]
] |
||
8tasy4
|
how do large scale (business, school, airport) wifi set-ups work?
|
I assume it is one modem and many routers? How does it seamlessly jump between them?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8tasy4/eli5_how_do_large_scale_business_school_airport/
|
{
"a_id": [
"e1621bh"
],
"score": [
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"text": [
"Commercial networks are setup differently than home networks. In your home you have a wireless router which serves as both a router(directs traffic to the right places) and a wireless access point(generates the wifi for you to connect to). In a commercial environment there is one router which is connected to lots of smart wireless access points\n\nThe wireless access points are all broadcasting the same SSID(network name) but on different channels so they don't interfere with the ones near them. By being on a different channel they can minimize interference between the two access points so that they aren't shouting over top of each other. Some of them can even adjust their power to reduce interference with their neighbors so they're just whispering near each other. As you start to move out of range of one, or as one gets overloaded, it may push you off to another access point on a different channel which can better serve you or your device may decide to change automatically. It all depends on the specific implementation.\n\nAll of these access points then feed back to a single router which is in charge of handing out IPs and connects back to a single modem which connects everything to the outside world, hopefully through a good fiber connection"
]
}
|
[] |
[] |
[
[]
] |
|
3i862r
|
why does paper appear wet after leaving leather on it overnight?
|
If I leave my headphones on my notebook over night, the area where the padding (leather I presume, though it may be fake) is on the paper appears to be wet. It creates a circle and "leaks" to the next page as if water was dripping on it, but it is dry. The reason I say it appears wet is because of a yellowish discoloration and the paper is more translucent.
Does anyone know what this is caused by?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3i862r/eli5_why_does_paper_appear_wet_after_leaving/
|
{
"a_id": [
"cue7fvb"
],
"score": [
3
],
"text": [
"maybe your headphones get oily from contact with your skin. That oil the transfers to the paper overnight."
]
}
|
[] |
[] |
[
[]
] |
|
5ge85y
|
how does acquainted taste work? why do some people have it and others don't?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5ge85y/eli5how_does_acquainted_taste_work_why_do_some/
|
{
"a_id": [
"darkg65",
"darkhyo"
],
"score": [
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4
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"text": [
"Do you mean acquired taste? No one has an acquired taste to start - you gain a taste for something only by experiencing it. That's what acquired taste means.\n\nThe best example I can think of is beer. Everyone's first beer tastes gross. It's only after you've had numerous beers that you begin to acquire a taste for it and it becomes more palatable. ",
"Do you mean acquired taste?\nIf so, it is to do with brain plasticity. Ie connections in our brains can change with use/exposure/practice. People vary in how plastic their brain is just like other traits. \n\nTL;DR \nSome peoples brain connections change more readily than others."
]
}
|
[] |
[] |
[
[],
[]
] |
||
3d7ocn
|
why does a movie like suicide squad have the trailer out now, but a release date in over a year from now?
|
What happens between now until release?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3d7ocn/eli5_why_does_a_movie_like_suicide_squad_have_the/
|
{
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"ct2kgka"
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"text": [
" > What happens between now until release?\n\nDid you see how many of the scenes had special effects? A lot of them, right? Adding special effects to raw film takes awhile. The raw, effects free, filming has been done. What they're doing now is adding effects, composing and adding music, etc. \n\nBasically, they're turning it from green screen to final film."
]
}
|
[] |
[] |
[
[]
] |
|
l0kts
|
I don't fully understand what hybridization is nor how to identify it?
|
Hybridization is when the electrons overlap? When does this actually happen? Is it only to carbon? What is sp1, sp2, sp3 exactly? How can you tell what are sigma bonds and what are pi bonds in a given compound?
Sorry guys I was just taught this yesterday and it's still not 100% understanding to me.
|
askscience
|
http://www.reddit.com/r/askscience/comments/l0kts/i_dont_fully_understand_what_hybridization_is_nor/
|
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"text": [
"Hybridization is when the wavefunctions of the orbitals add or subtract each other in order to form new orbitals. It is not when electrons overlap - that's just a simple chemical bond formed when a molecular orbital is made.\n\nHybridization theory can be applied to other elements, but is commonly applied to carbon to explain the configuration of organic molecules.\n\nsp, sp^2 , and sp^3 orbitals denotes how many of each subshell is used to make the hybrid orbitals. sp means one s-orbital, and one p-orbital combines to form two sp-orbitals. Likewise, sp^2 means one s-orbital, and two p-orbitals combine to form three sp^2 -orbitals.\n\nSigma bonds are formed by orbital lobes pointing at each other, and pi bonds are made by orbital lobes parallel to each other. [This site](_URL_0_) gives a clear example for ethene. The hybridized sp^2 orbitals are involved in sigma bonds, while the unhybridized p-orbital is involved in the pi bond in the C=C double bond.",
"I'm a student myself so take this with a grain of salt.\nI'm also learning this in German so my scientific English might be off.\n\nThe electrons don't overlap (Pauli exclusion principle), but their *orbitals* do. \n\nA hybrid orbital is when the 2s and 2p orbitals overlap (in a molecule). \n\nsp3 is a hybrid of 1x2s and 3xp orbitals \nsp2 is a hybrid of 1x2s and 2xp orbitals\n\netc.\n\nAll atoms have orbitals and some molecules have hybrid orbitals. Doesn't need to be carbon.\n\nSingle bonds are sigma bonds. \nDouble bonds are pi bonds.",
"Hybridization is when the wavefunctions of the orbitals add or subtract each other in order to form new orbitals. It is not when electrons overlap - that's just a simple chemical bond formed when a molecular orbital is made.\n\nHybridization theory can be applied to other elements, but is commonly applied to carbon to explain the configuration of organic molecules.\n\nsp, sp^2 , and sp^3 orbitals denotes how many of each subshell is used to make the hybrid orbitals. sp means one s-orbital, and one p-orbital combines to form two sp-orbitals. Likewise, sp^2 means one s-orbital, and two p-orbitals combine to form three sp^2 -orbitals.\n\nSigma bonds are formed by orbital lobes pointing at each other, and pi bonds are made by orbital lobes parallel to each other. [This site](_URL_0_) gives a clear example for ethene. The hybridized sp^2 orbitals are involved in sigma bonds, while the unhybridized p-orbital is involved in the pi bond in the C=C double bond.",
"I'm a student myself so take this with a grain of salt.\nI'm also learning this in German so my scientific English might be off.\n\nThe electrons don't overlap (Pauli exclusion principle), but their *orbitals* do. \n\nA hybrid orbital is when the 2s and 2p orbitals overlap (in a molecule). \n\nsp3 is a hybrid of 1x2s and 3xp orbitals \nsp2 is a hybrid of 1x2s and 2xp orbitals\n\netc.\n\nAll atoms have orbitals and some molecules have hybrid orbitals. Doesn't need to be carbon.\n\nSingle bonds are sigma bonds. \nDouble bonds are pi bonds."
]
}
|
[] |
[] |
[
[
"http://www.chemguide.co.uk/basicorg/bonding/ethene.html"
],
[],
[
"http://www.chemguide.co.uk/basicorg/bonding/ethene.html"
],
[]
] |
|
klu7o
|
Exactly how does the Dyson Air Multiplier work?
|
I understand at a basic level what's going on: air is sucked in through the base, and somehow manipulated through the hoop at the top to draw in air from behind and around the unit.
How exactly is that accomplished? What properties of air are being manipulated?
[Pic](_URL_0_)
[Video](_URL_1_)
|
askscience
|
http://www.reddit.com/r/askscience/comments/klu7o/exactly_how_does_the_dyson_air_multiplier_work/
|
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"Their [website](_URL_0_) is helpful. Basically the air they suck up from the base is accelerated and force out the little holes making jets (the red area in the image). Its like using your thumb on the hose to make the water go further (therefore faster). The difference in pressure pulls the air behind the fan through as well. ",
"[Viscous resistance/linear drag](_URL_0_)\n\n",
"It's air induction, a main flow of air pulls surrounding air into it and when it's forced through a smaller radius (the ring) it speeds up. Look up Venturi's. ",
"Their [website](_URL_0_) is helpful. Basically the air they suck up from the base is accelerated and force out the little holes making jets (the red area in the image). Its like using your thumb on the hose to make the water go further (therefore faster). The difference in pressure pulls the air behind the fan through as well. ",
"[Viscous resistance/linear drag](_URL_0_)\n\n",
"It's air induction, a main flow of air pulls surrounding air into it and when it's forced through a smaller radius (the ring) it speeds up. Look up Venturi's. "
]
}
|
[] |
[
"http://farm3.static.flickr.com/2437/4005911431_1bcb03b443_o.jpg",
"http://www.youtube.com/watch?v=PI_f9nFZAnk"
] |
[
[
"http://www.dyson.com/insideDyson/article.asp?aID=Air_Mult_Tech_Dev&hf=&js="
],
[
"https://secure.wikimedia.org/wikipedia/en/wiki/Viscosity"
],
[],
[
"http://www.dyson.com/insideDyson/article.asp?aID=Air_Mult_Tech_Dev&hf=&js="
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[
"https://secure.wikimedia.org/wikipedia/en/wiki/Viscosity"
],
[]
] |
|
103pci
|
If the speed of light never varies, what is happening to it in prisms and Bose-Einstein condensate? Does it not slow down in those cases?
|
askscience
|
http://www.reddit.com/r/askscience/comments/103pci/if_the_speed_of_light_never_varies_what_is/
|
{
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"text": [
"The short answer is that while c, the speed of light in a vaccum, never varies depending on how you move, the actual speed of a ray of light can vary depending on the type of material it is moving through.\n\nThe long answer is that the speed of light never changes, but as a photon travels through a substance, it is absorbed and re-emitted by the atoms of that substance. How often this happens, and how long the process takes, can make it appear that the photon is moving slower than c, when in actuality, it is travelling at c until it is absorbed, and then after a brief period of time, the atom that absorbed it emits the gained energy in a photon which then travels at c until it, too, is absorbed, and the process repeats.",
"To answer your question - c is the speed of light *in vacuum*. In materials, light can move slower than c. I posted a lengthy reply to some of the comments below that *incorrectly* said it is due to atomic absorption and re-emissoin. To re-iterate, the slowing of light is NOT due to photon absorption and re-emission by atoms."
]
}
|
[] |
[] |
[
[],
[]
] |
||
82lus7
|
why are movies available for purchase much faster to the public now vs recent years?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/82lus7/eli5_why_are_movies_available_for_purchase_much/
|
{
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"It's easier to do so nowadays, and the studios are trying to milk as much money out of a project as possible in the shortest amount of time.",
"Piracy. The longer people have to wait for a movie the more chance illegal downloads will happen... ",
"Its all about the money. The movie studios have realized that after the initial run in the theaters the movie is not making any money until it is released for home sale. The quicker the movie can get out for sale the more money it can continue to make. You will also notice that the biggest name movies from late summer/early fall will take a little longer to make it to video than movies from earlier in the year in an effort to align the release with the Christmas shopping season.",
"Movies don't run too long at theaters these days. In India atleast, growing up in the 80s and 90s, movie producers used to celebrate when a movie hit a \"Silver Jubilee\" (25 weeks) or \"Golden Jubillee\" (50 Weeks) streak at cinemas.\n\nA blockbuster may be shown for more than a month, but most movie audiences peter out by the 3 week mark.\n\nWith Netflix, Itunes and Amazon Prime, we have a new class of movie viewers, who are content to watch movies at home. These companies are desperately trying to get more subscribers, so they're willing to throw big money to producers for \"exclusive\" or \"first\" rights for internet streaming.\n\nSince DVD/Bluray purchases have come down from the VHS days, Online streaming money is a healthy boost, and the fresher the movie, the more money producers gain.",
"Also to capitalize on the advertising that was used for the theatre run. To keep it in the discussion. Out of sight, out of mind."
]
}
|
[] |
[] |
[
[],
[],
[],
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||
8cmd7s
|
why is britain considered the closest ally of the usa when the usa had to fight a war of independence to break free from britain? why is france not their closest ally since they fought alongside usa in the independence war and without them usa had very low chances of winning?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8cmd7s/eli5_why_is_britain_considered_the_closest_ally/
|
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"text": [
"That was a long time ago. Fighting together against Germany in WW2 cemented their alliance. Sharing a language and some culture helps maintain the relationship.\n\nBritain is also a relatively strong military power compared to most countries, with nuclear weapons and a permanent seat in the UN security council. It's useful to have them on your side.\n\nA lot of this applies to France too, which is also a close ally of the USA. Maybe the shared language is the reason why the UK is considered to edge out France as the USA's closest ally.",
"I’m not a historian but speaking as someone from New Orleans, there’s a greater impact from cultural exchange between the UK, Australia, and Anglophone Canada than there is from France or the Francophone (or Ghana). Despite the revolutionary war, most of the US remains culturally very English, partly due to language but also partly due to religion and customs. I wouldn’t say at this point that most Americans have Anglo-Saxon heritage, but for many, that was the assimilation ideal. In order to get jobs and positions of status, it was imperative for immigrants to adopt the culture of the current power structure. In South Louisiana, there are official celebrations of French and West African influences but in many parts of the United States, people still mention relatives who were on the Mayflower. \n\nTL/DR: culture and language dictate these things more than far-flung colonial wars of the 1700s. ",
"Mostly because we both still speak the same language. Same thing with Canada, we've been off and on at war with them before too, and we're allies now largely because of a lack of language barrier. ",
"Which France? The Kingdom of France, which hooked the U.S. up with a lot of support during the Revolution (as a political move to stick it to Britain)? The Republic of France, which we had an undeclared war at sea with (_URL_0_) for trying to claim old debts owed to the guillotined monarchy? Napoleonic France, which sold us a shit ton of land so they could afford to fight everyone in Europe?\n\nThe period after the founding of America was a pretty wild one for France. Upheaval after upheaval, revolution, counter-revolution, invasions to and fro, and so on. Britain, meanwhile, sat there and kept being Britain pretty much constantly. They already had a head start in being another English-speaking nation with a lot of overlapping traditions, common law, and so on, and the consistency of government made it a lot easier to form attachments. Then once the 20th century rolled around, America kept finding itself in common fights alongside Britain, which grew from 'allies of convenience' to a more genuine fondness, again assisted by all that stuff they have in common. ",
"The main reason France helped us is not because they loved us, it was because they hated Britain. \n\nCommon language, common heritage has forged closer bonds with Britain than France. All Americans are still technically \"former Brits\" so we share a common kinship with them. \n\nEven at the time of the Revolution, we didn't hate being British, we just hated being mistreated and ignored by the British Government, which is an important distinction.",
"France only fought along the USA in the independence war because Britain was getting too powerful and they wanted to cripple Britain, not because they really cared about US independence. This was before the French Revolution and the edict of fraternity, and in the 18th century America wasn’t really a plausible war time ally for France anyways - too far away. They just didn’t want Britain to have access to resources.\n\nFrance and the United States did have a mostly friendly relationship for a large part of history, depending on the nature of governance in France which has had a huge amount of political turnover right up until 1958. However put very simply France has made it a corner stone of their foreign policy to develop and maintain their great power status, and they have learned that they can’t rely on the United States to support their foreign policy goals. In fact France feels that the United States frequently undermines their ability to exercise power outside of their borders, either by countering their efforts (as in the Suez crisis or the Rwandan genocide) or by ignoring the authority of the institutions in which France has some power, like the Security Council (the Afghanistan war). Therefore France seeks to develop a global influence that is independent of the United States, for example they are the fourth largest military spender, they have their own independent nuclear weapons programme, and they have made many attempts over the years to develop a European controlled security organization (similar to NATO except it would exclude the US), although in the latter they haven’t been successful because the other largest European powers Britain and Germany aren’t game. \n\nOn the other hand, even though the US has undermined Britain’s ability to be a great status power too, britain has taken the approach not to bite the hand that feeds it. Britain has developed a unique role as the bridge between America and Europe, and that role gives them power. Since the US is more powerful globally than the EU, Britain’s strategy seems to be to wield power and amass security by getting closer to the United States, rather than by balancing against it like France has. \n\n",
"Well, to speak from a place of pure speculation and oversimplification I'll provide a different perspective.\n\nYou've got one group of people all socialised together, so sharing if not similar values, similar values about how disagreements are handled, some of them go off somewhere else for a bit.\n\nAfter a while, the guys that went away don't feel like the guys that stayed behind are helping them enough to stay allied with them.\n\nSo these dudes don't get along. Have a fight.\n\nLots of people are born and die. Both groups of people grow their own influence and are recognised as totally independent entities.\n\nWhy wouldn't they get along? Still got pretty similar core values. New queeny ain't asking for taxes no more.\n\nThey're still all basically the same dudes with the same cultural backgrounds, much larger slabs of common ground than other nations. ",
"We sometimes fight with our brothers for entertainment when we get bored. Doesn't mean we hate them. We just got bored. ",
"Call it a hunch, but there's a chance that situations change over 240 years?",
"Charles de Gaulle. That's why. The man absolutely dominated French politics from ww2 to about 1970. He had ..more tepid relationships with the US and UK. Pursued politics of grandeur - believed France should be an independent great power, developed nuclear capabilities, tried to counterbalance the US and Soviet influence, withdrew US military rights and left NATO. \n\nThe UK only really became the closest ally of the US after WW2, largely because of Churchill and to oppose Stalin and the Iron Curtain that had descended upon Europe. ",
"Another aspect: I've read suggestions that the UK reached out to t he US particularly after the Spanish-American War. Given the gradually rising tensions with Germany, the British realized they would benefit from a better relationship with this rising maritime power.",
"You can't get hung up on stuff that happened a long time ago, who cares which king demanded what from who 200 years ago, who will stand against our enemies today?\n\nWorld War 2 ended in 1945, and 3 years later the US mobilized the greatest airlift in world history to stop Stalin from starving West Berlin with a blockade. Alliances can change practically overnight and the American War for Independance has about as much bearing on modern politics as the 1st Crusade.",
"We fought a war of Independence from our brothers with help from our friends. But we always go back to family in the end but as equals.",
"Pre-World Wars history aside (It's been covered nicely in this thread) the UK and USA have fought and worked closely together in the major tank battles of The First Gulf War, in Afghanistan and still work and train together often. ",
"Enormous amounts of British investment in the US during the 19th Century meant that a lot of business was done between the two. British money financed a huge part of the American economy and it was a big market for American cotton and later kerosene. The UK was political and economically stable with huge cash assets and an experienced financial sector, so Americans could get credit and financial backing.\nEven today, the UK is the largest foreign investor in the US and vice versa.\n\nThe UK also settled its border issues with the US relatively early and without too much rancour, so it was not seen as a hostile force threatening the northern border of the US.\n\nLater, the UK came down on the side of the US in the Spanish American War and didn't take the opportunity to expand its Caribbean empire.\n\nBut the US/UK relationship wasn't stable until well after WW1 - right up until the 1930s, American warplanning, especially in the Navy, was to fight the Royal Navy - at that time the largest fleet in the World. The US was thrilled with the 1922 Washington Treaty that gave it parity with the Royal Navy, whereas in the UK, the treaty was denounced by many as a capitulation - even though it was clear the country couldn't afford to maintain naval supremacy and that the money was needed to rebuild the civilian economy and introduce a social security network.\n\nAs for WW2 - it's hard to underestimate the personal contributions of Roosevelt and Churchill to forging the relationship. They were the very best of personal friends, two of the most extraordinary politicians to have ever lived and we're all the better for them being alive at the same time.",
"Because modern political alliances are based on modern political conditions, not on historical colonial relationships. If conditions change, relationships will change. ",
"Technically Canada would be the closest Ally to the USA, we just don't have the military might. \n\nWe are also very close with Britain.\n\nLots of joint operations with both countries.",
"Not long after the end of the US war for independence, France went through a regime change and no longer had a monarchy. The old French government was the one that helped the US and created friendly ties with them. The new French government created tensions with the US. Since then, France never really became a close friend to the US until World War 1. ",
"I always assumed it was because we had so many relatives in England. Friends and family still there.",
"Because nobody really cares about what happened 100s of years ago compared to ease of cooperation over common interests today. ",
"France was and is weary of American influence in Europe. That was especially the case in the cold war period where France wanted a more independent European policy which didn't really sit well with the USA. Then there's also what other people have noted; some cultural similarities and naturally they use the same language. ",
"Following the war, that was swift recognition that Americans and the British shared more in common than they had against one another - recent war for independence or not. They spoke the same language, had the same family of religions, the same culture, and already had pretty deep business and economic ties to one another. \n\nThat latter one, right there, is sort of the magic: money. British and newly-minted American businessmen were quick to re-establish ties and (much of) the government followed suit. There was a faction (the Jeffersonians) who believed that closer ties with France was better for ideological reasons, but France didn't want those close ties because France was a monarchy and wasn't in the business of helping to free colonies and \"overthrow tyranny\" out of the goodness of their hearts. They wanted to stick it to Britain.\n\nKeep in mind too that there were many on the British side who supported American independence and that position only grew as the costs of the war did. Despite lofty ideals, the war wasn't one where there was much hatred between the two sides. ",
"Shared language (English), shared culture (dominated by Anglican/Episcopalian Protestants), mutual trade (look up the volume of trade between the UK and the United States circa 1900), distance (for most of our mutual history the Atlantic was simply too far for either power to threaten the other across), and co-belligerence in two world wars that exhausted the British Empire. Not to mention the fact that George III was not an especially sane or well-loved king and a great deal of the enmity between the two countries was royal pique.\n\nBasically, by the time the United States was big enough to really hurt Britain, or Britain could have plausibly done more than humiliate the United States, the two powers had been getting along decently for some time. A big part of that was reciprocity of needs; London had enormous financial markets, and the United States had vast natural resources. British capital was invested in America, American goods and raw materials fed British industry, rinse, repeat throughout the 19th century. This was well enough established to make war between the two countries distasteful to both as early as the 1860s (when, ironically, Napoleon III was pissing us off quite a bit by intervening in Mexico; by 1867 we were threatening war).\n\nIt's the same reason Weimar Germany and Soviet Russia cooperated between 1919 and the Nazi rise to power; Germany had industrial expertise and needed raw material (and somewhere to fool around with tanks in secret), the Soviets had raw materials and needed industrial expertise.\n\n(To answer the obvious question: India is different for a few reasons, even setting aside racism. Great Britain didn't conquer India in one go; they conquered Bengal, and then used local forces to conquer the rest of India in bites. And it was a generational process.)",
"In more recent years, the relationship between Reagan and Thatcher was a factor.\n\nThe inevitable wiki page on the \"Special Relationship\": _URL_0_",
"The answer your looking for, at least to explain the *current* relationship, is from the Suez Crisis. France, Britain and Israel collaborated to seize the Sinai and the Suez Canal from the Egyptians after it was nationalized by their (Egypt's) government (Without \"fairly\" compensating the British). After the British and the French entered posing as peacekeepers between the Israeli's and Egyptians, the US and USSR called on them to withdrawal. The UK, France and Israel gave in. The UK, for a long time afterward decided to not make unilateral decisions without consulting the US, lest it be embarrassed again. The French, meanwhile, decided to go their own way, develop an independent military and stay out of NATO. \n\nThe US's relationship with both countries is generally a continuation of that strategic policy.",
"Post WWI the world transitioned from the British Empire being the greatest power on the planet to the US supplanting that role. The UK saw it in their best interest to shepherd the US as it stepped into that role",
"Canada I would suspect is the USA's closest Ally. Britain is considered a closer Ally than France due to culture and language similarities. ",
"I think of America as a Britain's child. They start out young and reliant, then become rebellious in the teenage years, and finally as an adult they cooperate and take care of each other.",
"May I just state for a second that America's closest ally is probably Canada. We do have a special relationship with Britain that we don't quite have with France though. That mostly comes down to two reasons: The political reason and the cultural one. Britain speaks the same language, shares culture with the US, and has a constant stream of tourists. Politically speaking, Britain was the one who wanted to leave when we asked them during the Suez crisis. That's huge because ever since then they've followed America's lead in both international politics and domestic politics.\n\nFrance on the other hand has seemingly been fighting to establish itself as a country outside the American sphere of influence. The French famously refused to work with America during the invasion of Iraq. France in the aftermath of WWII refused to aid NATO military operations as a show of French force. The country has long held that they must be respected and seen as a power independent of America.",
"* Language - both speak English; not many Americans speak French or other languages like German (anymore; up to WW1, different story).\n* Culture/Legal - both countries use a Common Law legal system and share a ton of traditions and norms\n* Revolution - during the American Revolution, only about 30% of the population actually wanted a revolution; there where many pro-English American settlers. Today's \"anglophone\" are sometimes dynasties of those folks. In general, a revolution only requires about 10%-15% of the population going full-over to it to swing a nation.",
"Australia is a closer ally than either.\n\nGreat White Fleet\n\nANZUS\n\nfought together in the pacific during WW2\n\nKorea\n\nVietnam\n\nIraq\n\nAfghanistan",
"Lets not forget that England didn't care much about losing the colonies. It had its main armies busy in Europe with Napolean and the war in the colonies was just another issue it rather not have to deal with. Had the full force of the Bristish Empire been directed to the colonies, the US would have never gained independence. Instead, England just let whatever forces it had over there deal with the problem. ",
"You’re talking about events that happened almost 250 years ago. Things change. And the English and Americans have always regarded each other basically as cousins, with deep cultural and language ties, even if the US had to fight against them for independence.",
"To a lot of Brits the USA isn't considered such a special friend any more. The war in Iraq, Afghanistan, and now trump have made that the case. It could be argued that our politicians keep telling us the USA is our best friend to distract from the EU which to be honest in the 21st century are a better bedfellow",
"America is a British colony that gained independence yes, but the \"natives\" in question were still Englishmen. The country is still rooted in English culture in many ways. ",
"Most people assume that Britain and France have always been friends, but that was not true until fairly recently. Historically they have always been fighting and bickering. Britain has alway been sort of like the “parent” of Europe because they were so powerful and actually tried to solve issues with words rather than warfare. The US has had its issues with Britain in the past, but we have gotten over it and are now working together.",
"That was almost 250 years ago. Since then it was beneficial to trade with them and support Western Europe in both world wars. Remember the UK was the global superpower up until about 100 years ago. ",
"I already commented about how Britain isn't the greatest ally, but there were also large political shifts in not only post-revolutionary America, but the world. The US gained its independence with the help of the Kingdom of France. In the 1790's, France had overthrown the monarchy in favour of a republic. This might sound like a great thing for the US, but the new French Republic had just overthrown the government that aided the fledgling nation.\n\nIn the US, the Federalist Party attempted to distance itself from the revolutionary government that destroyed their ally, and attempted to foster better relations with GB. Not everyone was okay with this. Thomas Jefferson formed the Anti-Administration Party (Precursor to both the Republicans and Democrats). As we know with the War of 1812, the Democratic-Republicans (Successors of the Anti-Administration Party) declared war on GB.\n\nNow, to fully answer the question, France wasn't the US's ally because the government they were friends with no longer existed. The US was hostile towards the British for a long time, but time heals all wounds. They both stood for freedom in both World Wars, which may have served as a reason to stand together.",
"What language is the title of this post? That's why.",
"American revolution was a long time ago, recently they're closely allied with similar interests since WW1 and have each others back during hard times.\n\nYou could ask the same questions for Japan and Germany whom USA fought world wars against and dropped two nuclear bombs.They're now close American allies too.\n\nUK has also backed USA in more things than France. In military and intelligence sharing, wars and diplomacy they've backed each other.\n\nThen there's cultural connections, not just language but also in a way of doing things. A lot of Americans are of British descent like the founding fathers.\n\n",
"ww1 France got bodied and Britain stuck it out until we caved and sent them more equipment. \nww2 France got bodied and Britain stuck it out until we caved and bailed them out. \n \nnow add in the shared language, shared origin, similar culture, and Frances staunch refusal to be overtly friendly with anyone. ",
"I'm looking over the comments, and I'm not seeing enough credit given to the influence of religion. Religion may not be as influential now, but it was a huge factor for most of our history. The fact that the UK is a Protestant Christian culture, and France is historically Catholic, followed by being much more secular, should be accounted for. There has historically been a large number of Baptists, Presbyterian, Congregationalist, and Anglican/Episcopalian Protestants in the US. These denominations make up the majority of the Christians in the US (historically, at least; now, Catholics and Charismatics may have reduced the proportion of the list I gave to a minority fraction), and all of these denominations were founded in the UK and had their confessions of faith ratified in the UK, in statements of faith such as the Westminster confession and catechism, the Baptist confession of London, etc. In the 1700s. Prominent British preachers such as Charles Spurgeon and various authors kept influencing the American branches of these denominations throughout our history.\n\n(I don't remember whether the Wesleyan/Methodist denomination was founded in the UK as well, but add them to this list as well if they were. Was John Wesley from the UK?)\n\nThis historic Protestant Christian religious affinity surely plays a role in reinforcing the cultural affinity for the UK over France.",
"The French are stinky and start wierd revolutions, the Germans tried to take over the world twice, Asia has food we don't like, Italy has good pasta but the Mafia"
]
}
|
[] |
[] |
[
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Quasi-War"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Special_Relationship"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
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[],
[],
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[],
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||
p36d2
|
why is the british pound worth more than the us dollar? how are exchange rates determined?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/p36d2/why_is_the_british_pound_worth_more_than_the_us/
|
{
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"For most of the currencies, the exchange rate is determined by market forces while for some countries the rate is pegged to some other global currency. Very few countries try to have a more or less fixed exchange rate.\n\nUnder market force system, key determinants are inflation, interest rate, debt and the trade balance with other countries. \n\nActually, looking at a exchange rate at a given point of time is meaningless as it does not convey much information about the economies. It is just an equilibrium number supposed to signify the cost of goods in one country vis a vis the other. What one needs to look how the exchange rates moved historically and how they are expected to move in future.",
"I'm pretty sure based on my experience dealing with Bitcoin that exchange rates are simply determined by how many people have each unit of currency that are willing to sell, versus how many people are in need of each currency and looking to buy.\n\nLet's say you have $100 United States dollars and you are looking to sell them. You want to sell them for as much as you can get in £ (British Pound) because you're going there for vacation. You list your $100 on the market to anybody who is willing to buy it. You can list it for whatever price you want, but nobody is going to buy it unless your currency the lowest price on the market.\n\nThe current exchange rate (source: Google) for these currencies is 1 US dollar = 0.6358 British pounds sterling, or 1 British pound sterling = 1.5727 US dollars. So, if you try to sell your $100 for £70, nobody is going to buy it, because other people have it listed for cheaper. However, if you listed your $100 for £63.57, it would suddenly become the lowest price on the market (by only a penny) and would get bought up by the next person looking to buy it. Fortunately, there is a huge amount of people looking buy/sell currency at any given time, so I think this buy/sell process happens pretty fast.\n\nThat's basically the way any money market works... gold, silver, Bitcoin, expensive comic books, or any market that has value. The people in demand of the item are going to pay the lowest amount they can, but that price depends on the current supply combined with how many people want them (the demand). If the supply is extremely low but nobody wants an item, the value of it still isn't going to be very much.\n\nThat's basically how free markets / money supply works. I apologize in advance if there is something more complicated about how the currency exchange rate system works or if I didn't do a good job explaining it.",
"You're in America. You buy a hot dog. It costs $2. You go to England. You buy a hot dog. It costs £1. If the exchange rate is 2:1, you're paying the exact same amount, because when you went to the bank and turned in your American dollars, they gave you half as many British pounds. They just have different ideas about what one unit of money buys.\n\n[/ELI5]This gets more complicated when you start to look at actual pricing vs. exchange rates - when I was last in England, I found that, despite an exchange rate of 1.8:1, the prices were equivalent. In other words, that $2 hot dog was a £2 hot dog, meaning everything was 1.8x more expensive in England than in America. A $15 CD cost £15."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
5lg170
|
How are boreholes drilled in Antarctica?
|
I was reading about a borehole dug into the ice above Lake Vostok in Antarctica, and the article claimed that surface water of the lake was found at a depth of roughly 3,800 meters. How are holes such as that dug in those inhospitable conditions?
I've seen where large machines are used in oil fields, but it must be quite difficult to assemble such a thing on an ice sheet.
|
askscience
|
https://www.reddit.com/r/askscience/comments/5lg170/how_are_boreholes_drilled_in_antarctica/
|
{
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"dbw2e9x"
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"text": [
"You're right, it is very difficult. The drilling rig is flown in on transport aircraft and/or hauled across the ice to the drilling site. Otherwise, it's really not all that different than any other drilling. \n\nThe big difference is in the drilling fluid. In conventional drilling, you do that with varius \"Muds\" mixed with water. They provide the density and pressure to keep the hole from closing up on itself. In the case of the vostok boreholes, they obviously couldnt' use something water based, at least from one of the sources I saw, they used a mix of Kerosene (JP8 jet fuel) and freeon.\n\n_URL_0_ has some interesting information."
]
}
|
[] |
[] |
[
[
"http://www.southpolestation.com/trivia/10s/lakevostok.html"
]
] |
|
73nzs8
|
Any good books on the New Spain viceroyalty?
|
Latelly I am getting really interested on the colonial period of Mexico and central america so it would be nice to get some recomendations on some good books. I'm specially interested in the daily lives of people and how society worked back then. If you have any good material I'd be really grateful if you shared it with me. I can read english and spanish.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/73nzs8/any_good_books_on_the_new_spain_viceroyalty/
|
{
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"text": [
"Cool! Haven't seen anyone asking about literature on New Spain before.\n\nIf you're looking for a good and rather broad overview I'd suggest \"Gerhard, Peter: A guide to the historical geography of New Spain. Cambridge 1972\". The introduction goes into the administration and political organisation, so how the Viceroayalty was organized. It's followed by many maps of New Spain which has been very helpful to me.\n\n----\n\nI made [a short book list](_URL_0_) for the podcast I did here a while back, on native writers of colonial Mexico. The section on \"colonial Mexico\" might be interesting for you. Of those three, I'd suggest the Gruzinski as it's quite readable. The focus lies more on religious conversions by the church and orders however.\n\nAgain focusing more on the religious side is Hinz. Not sure if his 3 volumes I quote have been translated, but here's an [English article by him](_URL_1_) on the early \"hispanization\" which I found interesting.\n\nThe book by Lockhart is a classic in the field, but it's also very dense, so maybe better to look into later on. His focus lies solely on indigenous sources, which includes a lot of social history, and the lives of native commoners.\n\n\n \n----\n\nOne more book that I like is by María Elena Martínez: Genealogical Fictions. In it she looks at the influence of the Spanish limpieza de sangre edicts on the casta system in Mexico. More generally, it's a great overview of race relations and discrimination in colonial Mexico.\n\nThere are also some of my answers on New Spain on [my profile page](_URL_2_), which might have more literature I'm forgetting now. Let me know if you're looking for more/other suggestions on this."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/54ecfq/askhistorians_podcast_071_indigenous_writers_in/d818els/",
"http://revistadeindias.revistas.csic.es/index.php/revistadeindias/article/viewFile/645/712",
"https://www.reddit.com/r/AskHistorians/wiki/profiles/drylaw"
]
] |
|
2eqldg
|
what purpose does fort knox serve, since the united states no longer backs the dollar with gold?
|
The USA hasn't used commodity money since the 1960's, but Fort Knox is still a high security army base; what is inside?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2eqldg/eli5_what_purpose_does_fort_knox_serve_since_the/
|
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"text": [
"Fort Knox is an entire fort like most of the others in the US.\n\nThe US Bullion Depository (located in the area of Fort Knox) still stores a ton of gold. Currently it's holding 3% of all gold ever refined in human history. I'd say that's still gives purpose to the building.\n\nIt holds less gold than the Federal Reserve Bank of NY though (4.5k metric tons vs 7k metric tons at the bank in NY)",
"The US still *has* gold and some of it is still kept there. It's also just used as a *really safe place* to keep stuff. \n\nOriginal copies of the constitution, declaration of independence and the UK's Magna Carta have all had stays in Fort Knox. There's been crown jewels of foreign nations under threat and medicine secured away during the cold war too. \n\nIt's like the nation's safe. One of them, anyway.",
"Just because gold isn't the basis for our currency anymore doesn't mean it isn't still extremely valuable. \n\nAlso as others have pointed out the vault has been \"borrowed\" from time to time to store other extremely security-sensitive objects. \n\nAlthough my personal conspiracy theory is that there's actually not anything there anymore and we just continue to maintain it to distract people from the real super-secret vault. ",
"It is a reserve, just like the Strategic Petroleum Reserve, National Helium Reserve, Strategic National Stockpile (of vaccines and drugs), Highly Enriched Uranium Materials Facility, etc. To the degree that it's no longer essential for national security, it is anachronistic.\n\nFun fact: The US is one of the few nations to NOT have any food reserves."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
3rhdgi
|
Did China invent the steam engine?
|
I had a discussion with a friend about the steam engine. She claims the chinese invented it long before the western world. I havnt been able to find any real info about it on the web, its all just questions being asked but no credible answer. Do any of you know?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3rhdgi/did_china_invent_the_steam_engine/
|
{
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"No. Various conspiracy/sinologue-apologist/revisionists may suggest so, but it has never been mentioned by any credible, reliable, or otherwise historically viable source that I'm aware of.",
"Here's the important thing to remember about the steam engine: while there's early uses of something that can be described as steam power, (Hero of Alexandria is considered the first in the 1st Century; I've never heard of any in China) there's a lot of less 'big ticket' technology and science you need to have squared away before getting to what can be unambiguously labeled a steam engine in the way we usually think of them. So even if for the sake of argument there was some sort of steam or water-and-temperature powered device, it's not really an analog to a steam engine."
]
}
|
[] |
[] |
[
[],
[]
] |
|
tegqq
|
I'm writing an essay on Mohammad Reza Pahlavi, and his rule in Iran, but im not sure who to read when researching him. Can anyone help?
|
This is for a high school essay.
I have begun reading at my local university library but im really lost, there is a alot of books, and im not sure which author is more appropriate for me and my level of study, and also who is more reliable.
Ive begun reading "Capitalism and Revolution in Iran" by Bizan Jazani and "The Rise and Fall of the Shah" by Amin Saikal. But ive only scratched the surfaces of these two books because i cant borrow from the library.
Anyways, i would really appreciate if anyone has any knowledge of this area to help me out. Thanks, and if not thanks for your time, this subreddit is awesome.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/tegqq/im_writing_an_essay_on_mohammad_reza_pahlavi_and/
|
{
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],
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"text": [
"Charles Tripp has written a couple of books on Iran and is a ME expert, perhaps worth a glance?",
"\"All the Shah's Men\" by Stephen Kinzer, though it's more about Mossadegh than the Shah himself.",
"\"Democracy in Iran: History and the Quest for Liberty\" by Ali Gheissari and Vali Nasr (specifically Chapter 2), and \"The Shah\" by Abbas Milani are both accessible books by reputable scholars. They also have good bibliographies, so you can find more sources that way. If your school has access to any academic journals then you might have access to some of the articles cited in those bibliographies. You can also see if you have access to the International Journal of Middle East Studies. There are others, but that's a good one with a large selection of articles. Try searching through it and see what you find. Good luck!"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
87srxz
|
It’s Wednesday my Dudes! How long in advance did we know today would be Wednesday? When is the last time the days of the week were tweaked?
|
Were days ever added or subtracted? How long ago did this pattern of 7 days a week start? Are there any gaps?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/87srxz/its_wednesday_my_dudes_how_long_in_advance_did_we/
|
{
"a_id": [
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],
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"text": [
"Mentioning previous answers is intended as a starting point, not to discourage follow-on questions, info, or debate.\n\nThere's an FAQ section at _URL_1_\n\nIn the app, the \"#\" anchor doesn't work, so on that \"Calendars and timekeeping\" page, it's section Weeks, weekdays, and weekends\n\nThere are three discussions that look most pertinent to your question:\n\n* \"Was there ever a point in history where in some part of the world (a significant settlement) a week was not 7 days? How come we have 7 days to a week all over the world now?\" at _URL_3_ , /u/Duck_of_Orleans , /u/Algernon_Asimov\n* \"What were different cultures' and different time periods' equivalent of the Judeo-Christian seven day work week?\" at _URL_0_ . Algernon_Asimov again, /u/iwsfutcmd\n* \"When did the week become standarized across the world? Has there ever been differences in the day of the week, e.g. Tuesday in Germany but Friday in Russia?\" at _URL_2_ , with much about the \"weekend\" concept. Algernon_Asimov again.\n"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/v42xc/what_were_different_cultures_and_different_time/",
"https://www.reddit.com/r/AskHistorians/wiki/calendars#wiki_weeks.2C_weekdays.2C_and_weekends",
"https://www.reddit.com/r/AskHistorians/comments/1w76k0/when_did_the_week_become_standarized_across_the/",
"https://www.reddit.com/r/AskHistorians/comments/uvsog/was_there_ever_a_point_in_history_where_in_some/"
]
] |
|
58dr2a
|
why isn't being a mafia associate a crime?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/58dr2a/eli5_why_isnt_being_a_mafia_associate_a_crime/
|
{
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"text": [
"You can't be tried and jailed for merely associating with a criminal; otherwise many of us would already be in jail. For example, I have a friend who does heroin. Should I be put in jail because he's my friend? \n\nThe fact of the matter is that a person has to be directly linked to an actual crime in order to be tried and jailed. Just being a member of a gang isn't enough unless you can be linked to criminal activity."
]
}
|
[] |
[] |
[
[]
] |
||
aqe8bx
|
what is the difference mechanically between copying a file and moving it?
|
I was wondering if there's is really a difference. Depending on the difference, that could mean transferring consciousnesses would be possible without the problem of there just being a copy of you and the original you is dead.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/aqe8bx/eli5_what_is_the_difference_mechanically_between/
|
{
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"text": [
"Copy is to make a copy of the selected file or folder and place the duplicate in another drive or folder, while move is to move the original files from one place to another location. The move command deletes the original files, while copy retains them.",
"For a technical approach:\n\nCopying a file means reading the data and writing them somewhere else. In reality it is reading byte by byte at a certain offset in the source and writing it byte by byte to the same offset at the destination. The content of the source outside the offset being read is not relevant, it might or might not change after or before the file gets read.\n\nMoving a file means changing the metadata of the filesystem so that the file can be found in a different part of the filesystem. If the destination is outside the current filesystem, then it cannot be changed by metadata alone and the file needs to be copied (see previous paragraph) to the new filesystem and removed from old filesystem.\n\nNow to your philosophical question of transferring consciousness:\n\nYou are not moving here, the locations of source and destination consciousness are not in the same environment. So you need to copy. Would it be possible without being dead? Yes, just read the right data at the right location and write them at the right location. Is it possible at all? The current problem is that we are not aware on how the consciousness is located, let alone how it works, let alone how to recreate it. Fix these three things and you will be able to do it. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
6890yv
|
do other animals go through puberty?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6890yv/eli5_do_other_animals_go_through_puberty/
|
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],
"text": [
"Yes they do, but most of them go through it much earlier and much quicker than we do, and it's generally defined purely in terms of sexual maturity (i.e. puberty is the line between being able to, and not being able to breed). "
]
}
|
[] |
[] |
[
[]
] |
||
30x7s9
|
What's the history of prostitutes in Wessos?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/30x7s9/whats_the_history_of_prostitutes_in_wessos/
|
{
"a_id": [
"cpwnchu",
"cpwngaw",
"cpww02t"
],
"score": [
135,
38,
7
],
"text": [
"Are you referring to Westeros or Essos, perhaps?\n\nIf it is the latter, I would recommend \"Where the Whores Go\" by Ty R.R. Lancaster. He gives a lot of context for what kept \"the oldest profession\" alive in the east when it seemed to die out in the west. Spoiler alert: centralized religion.\n\nStill waiting on his next book, though.",
"**Written**\n\nDocumentation of prostitution in Westeros goes back all the way to the crossing of the Arm of Dorne by the First King. One account found in the Citadel of Old Town even suggests that it was a courtesan of the King who first suggested cutting down the Native Weirwoods, because she desired a litter made of the material. The First King was reputed to have brought an entire harem with him in his journey to Westeros. No accounts mention a practice of prostitution by any of the other sentient native species, though some say that the Giants have been known to 'loan out' wives in exchange for favors. Little is known about their culture so this account cannot be verified. \n\n**Archaelogical**\n\nResearch in this area is very limited, given that only three Maesters have ever forged the chain link for Archaeology. Maester Andun, assigned to House Dustin in the North, did take a particular interest in the history of the family and conducted a number of digs in the Great Barrow to learn more about the history of the family. His journal indicates sending a raven to Oldtown consisting of his findings, and indicates that Lord Dustin was not pleased with some of the conclusions drawn about his ancestors. The Citadel never reported receiving the message; it may have been intercepted by Lord Dustin's forces. Some scholars speculate that one of the ancestors of House Dustin was born of a prostitute, and not the Lord's wife. \n\nAdditional research in the crypts of Winterfell suggest that there were graves for \"companions\" near some of the eldest kings. This was often interpreted by the Stark lords to mean traveling companions or simply close friends. But a covert exhumation of one of the bodies by an anonymous party indicated that the bodies were buried with expensive jewels and had a feminine bone structure. The Stark family has denied any further requests to inspect the site.\n\n---\n\n**Sources**\n\n* Runes of the First Men, by Daeron Targaryen. Citadel Press, 158 AC.\n\n* Journal of Maester Andun, House Dustin. Citadel Press, 231 AC.",
"As a follow up and on topic, do we have any idea, written sources/oral traditions/pictographs?, of where whores go?"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
csim9k
|
how does your brain not bang the sides of your skull when moving your head about?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/csim9k/eli5_how_does_your_brain_not_bang_the_sides_of/
|
{
"a_id": [
"exeyy73",
"exf1tsv",
"exfdnah"
],
"score": [
10,
2,
2
],
"text": [
"To an extent it does, that’s how you can get concussions. But the liquid in your head cushions it and protects it from trauma like that.",
"That cerebral spinal fluid - CSF is enclosed in a seal system. As the name implies the fluid also cushions your spinal cord running down your back. A spinal tap or lumbar puncture, draws a very small amount of the fluid out to test for various illnesses.",
"At normal life speeds, the fluid that's between the tough layers of tissue which surround the brain is a shock absorber. It slowly squishes away from where the brain is pressed against the inside of the skull, dissipating the force. \n\nAt high speeds, like a car crash or even a fall where the head hits hard / bounces, that mechanism isn't sufficient to soften the force being generated. So the brain actually does slosh around some. A concussion is a bruise on the brain. \n\nWhen there's lots of force hitting the brain, it can slosh back & forth, being bruised both on the side toward the impact AND on the point across the brain from the actual impact."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
25la15
|
What were the conventions that governed the piano accompaniment of silent movies?
|
How did the players decide what to play? Were there set pieces that they improvised on as the scenes demanded (sad, rousing, suspense, ...)? Did they watch the movies a couple of times beforehand or did they jump right in? Were there training schools to become a movie accompanist?
Also: did some movies have official music scores?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/25la15/what_were_the_conventions_that_governed_the_piano/
|
{
"a_id": [
"chiamjt"
],
"score": [
5
],
"text": [
"All sorts of audio accompaniment took place at silent film showings, depending on the film, period, and locale. Silent film spans nearly 30 years and the world over, so there's really no single answer. Musical accompaniment could be live or pre-recorded (Thanks to, for example, a gramophone). It could be a pianist or a musical ensemble; many silent era movie palaces have a full orchestra pit that would be used to give silent films a complete orchestral score, live, as well as being used for other kinds of performance besides cinema.\n\nIt could even be absent. An alternative to musical accompaniment was a live narrator - In Japan, a narrator (*Benshi*) would contextualise the story and even voice the characters on screen. So there really is no single standard and I assume all possible approaches were taken at one point or another. Movie theatres in the USA originated as an outgrowth of vaudeville and other popular entertainment, which of course means there was already a cadre of working musicians to fill that role.\n\nSome silent films did have \"official\" scores - Chaplin notably composed scores for several of his films, including silent ones, and those scores would accompany the film itself on distribution along with strict (And of course, oft-ignored) instructions to play Chaplin's score and only his score. The various restored versions of Chaplin's films that you can find on streaming and home video versions were mostly put together by recording versions of the original, restored scores with help from Chaplin and his estate."
]
}
|
[] |
[] |
[
[]
] |
|
2yc7wu
|
In the 3rd century BCE why did the Macedonian Kingdom have so many rulers compared to the Seleucid or Egyptian Kingdoms?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2yc7wu/in_the_3rd_century_bce_why_did_the_macedonian/
|
{
"a_id": [
"cpgwtjr"
],
"score": [
2
],
"text": [
"I am not sure from where you are getting the sense that the Antigonid dynsaty (the Hellenistic rulers of Macedonia) was more numerous than the Seleucids or Ptolemies in the 3rd century. A brief look at some online sources give the following numbers:\n\n* [There were 5 different Seleucid kings in the 3rd century](_URL_1_).\n\n* [There were 5 different Ptolemaic kings in the 3rd century](_URL_0_).\n\n* [There were 5 (arguably 6) different kings of Macedonia in the 3rd century](_URL_2_).\n\nIs there a specific source or issue that you had in mind when asking this question? Or perhaps are you referring to the dynastic struggle that occurred in the early 3rd century BCE in between Cassander and Demetrius I, or the subsequent struggle between Antigonus II, Pyrrhus, Ptolemy Keranous, and the Galatians in the 280s? While these conflicts led to some dynastic instability, eventually Antigonus was able to re-install himself as king and stabilize his dynastic claim to the Macedonian throne."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Ptolemaic_Kingdom#List",
"http://www.livius.org/a/1/maps/seleucids.gif",
"http://www.livius.org/maa-mam/macedonia/macedonia4.html#After"
]
] |
||
1grejh
|
volts and amps and overall electricity
|
So I understand that volts times amps equals watts but what the heck is volts and amps physically? So confused with this
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1grejh/volts_and_amps_and_overall_electricity/
|
{
"a_id": [
"can1mwp"
],
"score": [
5
],
"text": [
"Amps is the easiest to understand. Current, measured in Amps is how many electrons are going by at in a second. Double the amps means double the number of electrons passed in one second. Amps is not energy because each electron could pass on more ore less energy. \n\nVolts are a little trickier. Although it isn't a perfect analogy the Voltage is how hard the electrons are pushing. The tricky thing about volts is it is measure of the difference between two points. You can't say the voltage at one place is 7 volts without meaning it is 7 volts more than somewhere else. Volts isn't exactly energy either because electrons could have high volts but if there aren't many of them still low energy. \n\nTechnically the voltage tells you how much energy there is per electron. That's why Amps x Volts is energy. Triple the volts means each electron has triple the energy. Triple the Amps means triple the number of electrons every second. Triple both the volts and the amps and you get 3X3=9 times the energy every second. \n\nThings that make electricity usually push out the electrons with certain voltage. That means a battery pushes electrons from one end of the battery out through the circuit and back to the other so that the difference between the start and end is 3 Volts. \n\nThe amount of current, amps you get depends on how hard it is for the electrons to go through. If it is easy, low resistance, then many electrons will make it through and give off their 3 volts. If the resistance is high then it is hard for the electrons to go through the circuit so not as many will go through and you will have a low current. \n\nThat is why V = (I)(R) or I = V/R : I is current, measured in amps, don't ask me why\n\n"
]
}
|
[] |
[] |
[
[]
] |
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