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3dzmmm
|
why does wikipedia cost so much to maintain if most of the people work for free editing the pages?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3dzmmm/eli5_why_does_wikipedia_cost_so_much_to_maintain/
|
{
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2,
3
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"text": [
"The Wikimedia Foundation, the parent organization of Wikipedia, employs a lot of people to maintain the site and the hosting. That isn't free.",
"The traffic Wikipedia endures on a daily basis is what drives the cost up so high. The actual size of the website is pretty easy to maintain.",
"Wikipedia gets almost 500 million unique visitors per year. And each unique visitor might view dozens of pages.\nEven if it only costs one cent to serve all the pages a single person might view in a year, that's still five million dollars worth of bandwidth and hosting. And that doesn't even take into account the paid employees, technical troubleshooting and upkeep, etc."
]
}
|
[] |
[] |
[
[],
[],
[]
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||
2n374l
|
why do certain grapes make your mouth dry when you bite into them?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2n374l/eli5_why_do_certain_grapes_make_your_mouth_dry/
|
{
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"cm9vt65",
"cm9vwex"
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"score": [
4,
2
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"text": [
"Because they have [tannin](_URL_1_) in them. Tannin is an [astringent](_URL_0_) compound, which means it binds to certain proteins in your mouth and tends to shrink and constrict body tissue.",
"They have a lot of tannin in them which creates the sour pucker your mouth flavour that you get from some dry wines. The reason for this is that tannin is not present in any food which gives us nutritional value and thus our bodies evolved to give the dry mouth signal when eating something with a lot of tannin. Obviously now days we ignore that reflex of the body and continue to drink that glorious scarlet liquid. I am about to tuck into a bottle of Gewurztraminer and a small cheese board. \n\nEdit: Sorry I realised I was wrong, it's not that tannin is in things with low nutritional value, it's that tannin makes your digestive system less effecient by bonding with the digestive juices which in turn decreases the amount of nutrition gained from food eaten whoile the tannins are present in the body. "
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Astringent",
"http://en.wikipedia.org/wiki/Tannin"
],
[]
] |
||
ezcbpa
|
what goes into a whiteboard paint that makes it finish like a dry erase board and not a normal paint?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/ezcbpa/eli5_what_goes_into_a_whiteboard_paint_that_makes/
|
{
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"text": [
"Dry/wet erase markers are basically just an ink that dries into something that doesn't stick well to a surface - dry erase forms a film, wet erase is water soluble. \n\nThis works on any surface, in theory - you could use dry erase on rough wood, except that it would seep into pores and cracks and other rough spots before it dries, making it really hard to remove. \n\nOn the other hand, if you use it on something smooth and \"non-porous\" (which means it has no holes, even tiny tiny ones), it's very easy to wipe off the surface. \n\nSimilarly, you can use high gloss tile as a white board, but if you use tile that isn't high gloss, you will have a very hard time wiping it off. \n\nWhiteboard paint is mostly just a paint that doesn't have those tiny holes. It's very very smooth, which makes it more shiny. It also has chemicals that make it have high surface tension (like a water drop) so that it dries nice and smooth, unlike normal paint that's designed to not hold together as well, making it flow into cracks better."
]
}
|
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[] |
[
[]
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3vtiit
|
government encouraging marriage
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3vtiit/eli5government_encouraging_marriage/
|
{
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"text": [
"It's not so much marriage that they're encouraging as being a stay-at-home spouse. There's only really a tax benefit if one person is making most of the money. If the two people make even close to the same amount of money, they pay less in taxes by filling separately. "
]
}
|
[] |
[] |
[
[]
] |
|
3l3qvw
|
why are music apps like spotify so much more ad intensive on phones than their computer counter parts?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3l3qvw/eli5_why_are_music_apps_like_spotify_so_much_more/
|
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"text": [
"It's rather simple really. Consider a billboard on the side of a road. If the road is a highway with many cars driving past, the billboard will be much more effective than a billboard next to a small farm road. The internet is the same, people tend to advertise where the most users are. Advertisers have tools that tells them how much traffic they get from mobile devices vs their computer counterparts.\n\nThe simple fact is most users are digesting content on a mobile device, which they have with them all the time (e.g. smart phone) as opposed to a desktop computer where they will only spend time on occasionally. By running more ads on mobile, advertisers are reaching more people than they would on desktop.",
"Not really about the number of users at all. Look at television- a show with 100k viewers on some deep cable channel has the same amount of commercials as a show with 2 million viewers on a more popular channel. Less users just means lower cost of advertising, but there's not a significant enough \"lack of advertisers\" to not be able to play you an ad.\n\n\nThe reason there are more ads on mobile is because it costs more to play the songs. Music services such as Spotify pay money to the rights holders (a small number of music publishing companies) to be able to play you the songs that they own. Those music publishing companies have decided that, for whatever reason, they will charge Spotify and other streaming services more money to play their songs on mobile devices vs. desktops.\n\n\nTherefore, to offset the extra cost, Spotify (like all companies) passes that cost off to you in terms of more ads.\n\n\nA few years ago, Spotify (non premium) was just like Pandora in that it would only stream you songs in a discover / radio way on mobile, where you could only choose a starting point and had no real control over what actual specific songs you would be hearing. Then Spotify renegotiated contracts with the music publishing companies allowing them to steam you artists and playlists on mobile, as long as it was on shuffle and more than x number of songs (I think the number was 20). \n\n\nTL;DR\n\n\nIt's not about number of users. It's about how much it costs for streaming services to secure the rights to songs, and it's more expensive on mobile devices so they need more ads to pay for them. "
]
}
|
[] |
[] |
[
[],
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||
4ovv0g
|
why are there so many more 'simple' medical procedures available for humans than there are for animals?
|
I am not sure if the answer is more about lack of willingness or lack of resources...
I mean stuff like;
Say a person was hit by a car and had some internal organ damage. For a human that requires bed rest and maybe some minor surgery. For a cat/dog, it requires euthenasia, why?
In the same vein, if a person becomes paralysed e.g. from the waist down, they get a wheelchair. An animal gets death? Where are all the kitty wheelchairs?
I understand not operating on an old animal, in the same way an old person might sign a DNR, but why are so many young animals put to sleep for relatively small things? Maybe the vets of reddit can shed some light :)
I ask because my 1yo cat was hit by a car in April, something must have severed spinally because both back legs were paralysed but apart from that no other external or internal injuries. We had to have him put down :( RIP Strider.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4ovv0g/eli5_why_are_there_so_many_more_simple_medical/
|
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"text": [
"Most animals don't have insurance. There are procedures for a lot of stuff, but not everybody can or wants to pay $5,000 when a cat & dog can be replaced for nothing.",
"Mostly it's money. Most people simply can't afford to spend multiple thousands of dollars on a pet.\n\nThe other big problems is that animals cannot take care of themselves. You can't prescribe a horse bed rest, because it's a horse and it isn't going to rest unless you keep it doped to the gills. Seriously injured animals are just not nearly as likely to recover a good quality of life as humans.\n\nIt also helps to remember that as animals go, humans are incredibly robust. We are really, really good at taking a beating.",
"It depends on the owner and the vet to be honest. A cat with two paralyzed legs can survive you can adapt two wheelers for it ( like a tiny wheelchair) if you take proper care of it but it takes time and money and owners are not willing to do that for their pets. I wouldnt have put that cat down by what you are saying, only if asked. But also its not only the paralyzed legs that is the problem your kitty would've been incontinent, would've been more prone to bladder infections, his bladder would need to be expressed, like I said its up to the owner and what is willing to do for its pet so that is why sometimes the humane thing to do is euthanize them because even tho you love them you just dont have the time to care for them. Im using your case as an example tho in some cases pets just dont recover and they live in constant pain so the better thing for them is to put them down. \n\nAnimal's bodies simply cannot handle stress the way we do. \n\n\n",
"my coworkers dog got hit by a car. his dog's medical bill currently stands at $25,000. the dog's alive but owner is about to go bankrupt. "
]
}
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[],
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1hj6xf
|
what is the difference between fat, saturated fat and trans fat? and what is the sudden big deal about trans fat?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1hj6xf/eli5what_is_the_difference_between_fat_saturated/
|
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"text": [
"Fats are a type of carbon-chain that your body uses for energy. Carbon atoms are able to form up to four bonds with other atoms.\n\nSo a saturated fat is where the carbon chain is entirely single-bonded. The 'saturated' part comes in because most of those carbon bonds are bonded to hydrogen atoms; in fact, the most number of hydrogen atoms the carbon chain can hold (thus 'saturated' with hydrogen atoms). Studies have shown that saturated fats are associated heart disease and other vascular issues. Saturated fats typically come from animals, and typically solid at room temperature as the single-bonded carbon chains are very flexible and can tightly pack with each other.\n\nUnsaturated fats have one or more of those single carbon bonds have been changed into a double-bond. This removes some of the hydrogen atoms from the chain as a result. Mono-unsaturated means only carbon double-bond has been formed, but you can have poly-unsaturated which can have several carbon double-bonds in the chain. Unsaturated fats are typically from plant sources, and are usually liquid form at room temperature because the double-bond is a much more rigid bond and causes the carbon chain to take a sort of 'kinked' shape.\n\n[Here's a picture of the two types just for a comparison.](_URL_0_) Note the way the unsaturated chain is bent at the double-bond, that will be important in the next section.\n\nTrans-fats are a type of unsaturated fat, and studies have also linked these to heart disease to an even greater degree of severity than saturated fats. As I said earlier, unsaturated fats are typically liquid (more bonds = more likely to be liquid at room temperature), and humans usually use solid fats for cooking. As such a process called 'hydrolyzing' which adds hydrogen atoms to the fat chain, removing some of the double-bonds so that the unsaturated fat can be made into a more marketable form.\n\nNow remember that 'kink' I mentioned in the unsaturated fat? Well when a double-bond is made, it can take one of two forms (called isomers), known as either trans- or cis- arrangement, which basically describes how the atoms are arranged relative to each other. Cis- arrangements are the common form in nature, but the artificial hydrolyzing process creates trans- isomers of the fat.\n\nHere's an image of a [trans](_URL_2_) compared to a [cis](_URL_1_) unsaturated fatty acid. Both have the same number of atoms, but vastly different shapes, and this geometric arrangement impacts how they interact with the body.\n\nThe exact mechanisms that make trans-fat unhealthy for you aren't exactly known, but one leading theory is that the body simply doesn't have the enzymes to breakdown trans-fats as they are artificially created. This is partially supported by another study that found naturally occuring trans-fats that did not seem to carry the same health risks (as they were naturally occur, thus creatures evolved ways to break them down, as opposed to our artificially created trans-fats).\n\nNot a nutritionist or a science major, so I may have glossed over some important details, but I think I got the basics covered.",
"This answer assumes some knowledge of atoms and molecules, and obviously there are more complex explanations. But the short version is that saturated fats and trans fats are bad, mmmkay?\n\nFat is a type of macronutrient - our body can burn fat molecules for energy, the same way it can burn protein and carbohydrate molecules. Fat molecules are mostly made of chains of carbon atoms, with hydrogen atoms bonded to them.\n\n[Saturated, monounsaturated, and polyunsaturated fat](_URL_0_) refers to the chemical structure of the fat molecule. Saturated fats have the maximum number hydrogen molecules bonded to every carbon atom (they are *saturated* with hydrogen), but unsaturated fats have one (mono) or more (poly) double bonds between carbon atoms somewhere along the chain, which means fewer hydrogen atoms.\n\nThe more saturated a fat is, the more likely it is to lead to an increase in the proportion of LDL ('bad') cholesterol in your blood, and contribute to coronary heart disease. Unsaturated fats are more likely to increase the proportion of HDL ('good') cholesterol.\n\nTrans fats are a special type of *unsaturated* fat, and are almost exclusively man-made. The 'trans' part of the name refers to the arrangement of the atoms around the carbon atom. Usually the hydrogen atoms are on the same side of the carbon atom (the *cis* configuration), but in a trans fat they are on opposite sides (the *trans* configuration). The outcome is that trans fat molecules act like even worse versions of saturated fats, despite being unsaturated.\n\nIn 2002 [The US National Academy of Science concluded](_URL_1_) that there is no safe level of consumption for trans fats. Every gram of man-made trans fat you eat contributes to factors that can lead to your early death."
]
}
|
[] |
[] |
[
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"http://mypcos.info/1/wp-content/uploads/2010/07/Sat-Unsat-Fat.jpg",
"http://upload.wikimedia.org/wikipedia/commons/2/27/Oleic-acid-3D-vdW.png",
"http://upload.wikimedia.org/wikipedia/commons/b/bc/Elaidic-acid-3D-vdW.png"
],
[
"http://en.wikipedia.org/wiki/Fat#Saturated_and_unsaturated_fats",
"http://en.wikipedia.org/wiki/Trans_fat#Nutritional_guidelines"
]
] |
||
5ebo93
|
How does human saliva composition differ from that of cats and dogs?
|
I understand there are certain factors, such as overall health or whether or not an animal has ingested something rancid, which impact results. I would like to know the cleanest (no pun intended) science which compares the overall saliva composition of humans, cats, and dogs. Specifically, I am most interested in the differences between "positive" (such as any healing properties) and "negative" (germs) aspects of saliva composition. Of course, studies needn't investigate all three species at once as we can compare results ourselves, so please just contribute what information, whether it concerns one, two, or three species.
Tranference (via licks and kisses) might vary and to a lesser degree I am interested in this as well. However, please do not hesitate to share saliva composition without any information on transference as it is a secondary concern.
|
askscience
|
https://www.reddit.com/r/askscience/comments/5ebo93/how_does_human_saliva_composition_differ_from/
|
{
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"text": [
"saliva is for:\n\n* keep the mucosa wet\n* lubricate food with water (or it may be too dry)\n* dissolve taste vector molecules inside food (very important because it's like a fast chemical analysis on the food and may help to decide if that thing can be eaten)\n* start to digest food\n* keep a microorganism-free environment (or at least try)\n\nsaid that, it's no surprise that, since we are different from cats and dogs, we all have different salivas (and different digestive secretion at the end of the day, because saliva is *just another digestive secretion*).\n\nwe are made to eat different things so it's not strange that we have different microorganisms in our mouths so the different salivas try to protect from different dangers, and we try to predigest what we have eaten.\n\ncats and dogs are not starch eaters while humans eat starch.\nI wouldn't find it strange if there wasn't any amylase ( the starch digester enzyme) at all in carnivorous animals' saliva like cats and dogs, where there is amylase in human saliva, and that's normal because we are more omnivorous.\n"
]
}
|
[] |
[] |
[
[]
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|
2d01d2
|
How would 17th century sailing companies, navies, and pirates deal with men who fell overboard?
|
We got into a discussion at work about falling overboard a sailing vessel and being left behind. We were curious about the following question:
How would 17th century sailing companies, navies, and pirates deal with men who fell overboard?
Would there be any attempt to save a man who fell overboard? Did different groups during the era have differing policies/procedures? Was there a status level (rank? worth? aristocracy?) at which one would be worth an attempt at saving? Are there any great man-overboard stories?
Thank you so much for any consideration!
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2d01d2/how_would_17th_century_sailing_companies_navies/
|
{
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"text": [
"My friend /u/RMission wrote an article on this subject, in particular how people back then would be revived from drowning: \n \n[Resuscutation of Drowning Victims at Sea](_URL_0_). \n \nIt will inform you of the subject more than you could imagine. ",
"It's from the 19th century and not the 17th, but Herman Melville talked about the subject a little in his novel [White Jacket](_URL_0_) (in which he describes life aboard a Man-o-War).\n\nHere one passage I found:\n\n > In men-of-war, night and day, week in and week out, two life-buoys are kept depending from the stern; and two men, with hatchets in their hands, pace up and down, ready at the first cry to cut the cord and drop the buoys overboard. Every two hours they are regularly relieved, like sentinels on guard. No similar precautions are adopted in the merchant or whaling service.\n\n...\n\n > Next day, just at dawn, I was startled from my hammock by the cry of \"All hands about ship and shorten sail!\" Springing up the ladders, I found that an unknown man had fallen overboard from the chains; and darting a glance toward the poop, perceived, from their gestures, that the life-sentries there had cut away the buoys.\n\n > It was blowing a fresh breeze; the frigate was going fast through the water. But the one thousand arms of five hundred men soon tossed her about on the other tack, and checked her further headway.\n\n > \"Do you see him?\" shouted the officer of the watch through his trumpet, hailing the main-mast-head. \"Man or buoy, do you see either?\"\n\n > \"See nothing, sir,\" was the reply.\n\n > \"Clear away the cutters!\" was the next order. \"Bugler! call away the second, third, and fourth cutters' crews. Hands by the tackles!\"\n\n > In less than three minutes the three boats were down; More hands were wanted in one of them, and, among others, I jumped in to make up the deficiency.\n\n > \"Now, men, give way! and each man look out along his oar, and look sharp!\" cried the officer of our boat. For a time, in perfect silence, we slid up and down the great seething swells of the sea, but saw nothing.\n\n > \"There, it's no use,\" cried the officer; \"he's gone, whoever he is. Pull away, men—pull away! they'll be recalling us soon.\"\n\n > \"Let him drown!\" cried the strokesman; \"he's spoiled my watch below for me.\"\n\n > \"Who the devil is he?\" cried another.\n\n > \"He's one who'll never have a coffin!\" replied a third.\n\n > \"No, no! they'll never sing out, 'All hands bury the dead!' for him, my hearties!\" cried a fourth.\n\n > \"Silence,\" said the officer, \"and look along your oars.\" But the sixteen oarsmen still continued their talk; and, after pulling about for two or three hours, we spied the recall-signal at the frigate's fore-t'-gallant-mast-head, and returned on board, having seen no sign even of the life-buoys.\n\n > The boats were hoisted up, the yards braced forward, and away we bowled—one man less."
]
}
|
[] |
[] |
[
[
"http://www.piratesurgeon.com/pages/surgeon_pages/drowning1.html"
],
[
"http://www.gutenberg.org/files/10712/10712-h/10712-h.htm"
]
] |
|
8yfcor
|
How can I identify who the people buried at the grave site I found on my families texas red river ranch are?
|
This question has a couple parts
(1)So basically my family owns a ranch on the red river and we found 3 (expensive looking for the time) grave stones dated from the 1880s-1890s buried on a nice hill overlooking where the river bank use to be. They were all under 35 2 females one child. How can I find out who these people are and how they died I'd like to know the truth my family has ideas?(discussed later)
(2) We contacted the local tax office but they said all their records from that time period were lost in a fire. My grandpa has created some crazy ideas about how they died, he tells people it was probably Indian raiders coming across the red river and raiding one of the men who lived on the river and who was a buffalo hunter that went out hunting, leaving his family behind and while he was out the local tribes probably robbed and killed the women and children, while he was away, twice.(did this actually happen on the red river between 1880-1890? It sounds unlikely it would happen to the same guy twice)
(3)We would also like ideas on how to properly preserve the area, the letters are fading from the tombstones and we want to do something to preserve the area in case they have any surviving family who would want to see it... so anything helps
Ty again yall I know it's a lot but we really do just wanna learn about and preserve these people's memories
Edit*pretty sure I used the wrong from of family's in the title please dont not answer because of it
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/8yfcor/how_can_i_identify_who_the_people_buried_at_the/
|
{
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"text": [
"Texas counties will typically have a Tax Assessor-Collector and a County Clerk. The Clerk keeps records of birth and death, amongst others. Their records may well have been co-located and both lost in the same fire, but you never know. If by \"tax office\" you didn't mean the County Clerk, you may want to check with them.\n\nThere are also census roles, immigration logs, and various other sorts of documents that can be used but are hard to track down. As mentioned elsewhere, genealogists often have these already in a processed and search-able form."
]
}
|
[] |
[] |
[
[]
] |
|
1uyn5v
|
what sound properties do different musical instruments have different from each other?
|
This has always baffled me and I never got a real answer for it.
Light waves have a frequency and an amplitude. The frequency determines the colour and the amplitude determines the brightness (I'm only taking the visible spectrum into account). That's understandable enough.
Sound waves also have a frequency and an amplitude. This time the frequency determines the pitch and the amplitude determines the loudness. But then, how do different instruments, or different words for that matter, all sound unique to us? A violin and a piano playing the same note still sound very different from each other, and the same goes to different spoken words. I suspect that the real reason is that each instrument produces a lot of different waves at different frequencies, which when added together can be heard as a specific sound. But I doubt it is this simple, and this doesn't really explain how different instruments can play the same note but still sound different from each other.
The same problem also applies to computer image and audio files. Creating an image file from scratch is very simple, and understanding how the image data is stored also seems simple enough (if you exclude compression). Each pixel stores 8-bit values for red, green and blue (and I think transparency as well), and that's pretty much it.
But on the other hand I have no idea how audio information is stored in a computer. I also have no idea if it's possible to just created a sound from scratch. I don't think you can do it in the same way as you can open Paint and just scribble around.
It would be great if someone could explain this stuff to me. Thanks!
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1uyn5v/eli5_what_sound_properties_do_different_musical/
|
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"text": [
"This has a lot to do with overtones and resonance. \n\nResonance is pretty self-explanatory: how well something (in the case an instrument) resonates throughout a room or building due to the sound waves bouncing and amplifying for a short period of time. \n\nOvertones are what make a sound \"thick.\" When an instrument plays a note, there is a dominant pitch that registers. However, there is also normally other pitches that \"surround\" that pitch to make it sound fuller. Think of a male falsetto note, or Pavarotti hitting that same note. One is thin without many overtones, and one is huge and thick.\n\nIf you play a note around a middle C on a piano and on a trumpet and a well-trained tenor sings the same note, none of these three things will sound the same as you have mentioned. This is because the piano has a fairly thin sound (less overtones), the trumpet uses its brass make-up to increase resonance and overtones, and a tenor would use his entire chest and nasal cavity to resonate the sound a fill an opera house. This applies for all musical instruments with some louder, thinner-sounding, thicker-sounding, irritating, warm and colorful etc..\n\nThis isn't a conclusive answer to your question but it is a little knowledge that I know and I hope it's helpful."
]
}
|
[] |
[] |
[
[]
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1rdpsh
|
does heat affect the energy absorbed by a solar panel?
|
I've been trying to better understand solar panels for a science fair project and my project is based around temperatures affect on them. I've received conflicting answers in my research and couldn't find a similar thread in ELI5.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1rdpsh/eli5_does_heat_affect_the_energy_absorbed_by_a/
|
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"[Wiki section](_URL_0_)\n\nSo your run of the mill solar panel works because the electrons in the silicon are separated into two layers. There is a bottom layer of electrons with the silicon itself (the valence band), a layer of no electrons (band gap) and a top layer of electrons that move around (conduction band). A photovoltaic cell works be having a photon (light particle) come in and give its energy to an electron in the lower layer so that it can jump from the inner layer over the layer of nothing and into the top layer where the electron can move around and essentially create a current. [This is also why silicon is called a semi conductor, because it conducts in some situation and insulates in others]. \n\nNow, that band gap (the layer of nothing) is partially dependent on temperature. Temperature is sort of like the average energy of all the electrons, the majority of which are in the lower valence band. A higher temperature means that they will have a bit more energy and the band gap will be smaller, so you'll get more current out of your cell which is good.\n\n Bandgap has its fingers in many pies though, and changing the temperature is changing the bandgap. Changing the bandgap will change the highest possible voltage that the circuit can have. Higher temperatures end up having lower maximum voltages\n\n[This graph](_URL_1_) pretty much explains what happens with temperature. Higher temperatures mean higher current and lower maximum voltage. The voltage rapidly decreases though, so you can think of it as either on or off, and so you'd generally want higher temperatures. At any rate, the effect is fairly marginal. \n\nedit:I wrote this on the fly so I can reword things if it is confusing. ",
"I don't have the knowledge of semiconductor physics to explain why solar panels work less well when they're hot. Most things, as they get hot, act as if they have a higher resistance to the flow of electricity. But why is that? One explanation I see is that hot atoms jump around more than cold ones (that's the definition of \"hot\" on an atomic level), so the electrons have a harder time flowing around the atoms. See _URL_0_\n\nAnyway, regardless of the actual reason, I see no conflict in the answers that I have googled. When I googled this, every single answer said: \"solar panels deliver less power when they are hotter\".\n\nHere's an explanation that claims to explain why. I don't claim that I understand it in detail: _URL_1_\n\nHere's someone actually doing the test and their resulting data (just one of many that I found): _URL_2_"
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Theory_of_solar_cells#Cell_temperature",
"https://en.wikipedia.org/wiki/File:I-V_Curve_T.png"
],
[
"http://regentsprep.org/Regents/physics/phys03/bresist/",
"http://scienceline.ucsb.edu/getkey.php?key=2668",
"http://www.reuk.co.uk/Effect-of-Temperature-on-Solar-Panels.htm"
]
] |
|
46ywe0
|
why do most countries use the same calendar?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/46ywe0/eli5_why_do_most_countries_use_the_same_calendar/
|
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"Europe and North America, which use a calendar based on the Christian calendar, export a lot of goods around the world. Other countries use the calendar because their major western trading partners do. ",
"Most countries in Europe came to use the Julian calendar (developed by the Romans), with some revisions endorsed by the Catholic Church, which we call the Gregorian calendar. The power of European colonization, trade, missionary work and military might spread it across the globe, and the last holdouts eventually bowed in the face of the benefits of standardization. Some do maintain parallel calendars to the Gregorian calendar, though.",
"Colonization.\n\nThe world was conquered by a few super powers and they implemented their culture, including calendars and timekeeping, wherever they went. Besides, travel and trade are easier when everyone is tracking time the same way. So, some places still respect their cultural calendars (like the Chinese and Hebrew calendars) while officially operating with the same calendar as the rest of the world.",
"It makes it way easier to organise dates. Thus making it easier to trade with different people on the planet or establish global relationships. \n\nIf there would be another calendar in place in France for example, I would be slightly discouraged trying to establish a private or professional relationship there. \n\nSame goes for the time.\n\n**TL;DR** It just makes things easier on a global scale",
"Why didn't a standard measurement system take off? ",
"As explained below, a lot of standardisation comes from not only Exploration Era European powers spreading the Gregorian calender, making other nations at the time use it for trade benefits. \n\nHowever some countries still adhere to their own standards. \n\nFor example- the one I know of is Japan, where while in international business they'll use the A.D. time scale, but in every day life, they use the number of years since their latest emperor was coronated (IIRC) . \nSo currently it's the 26th year of Akihito's reign as Emperor, which over there is known as the Heisei (㍻) Period. So in most governmental and every day things the date is written as ㍻26年2月22日 or The Heisei Era's 26th year, 2nd Month, 22nd Day.",
"Trade. Wars are fun to learn about, but economics shaped history. \n\nBut just so you know, there have been attempts. The French went so far as to euro-fy time. Down to ten hours in a day and even 100 \"decimal minutes\" in an hour. \n\nMy favorite is kodaks calendar. They used it for the internal business structure as late as the 90's, but it was also proposed as an international replacement. Kodak used it so long mainly because it made bookkeeping and accounting much easier because it you didn't have to worry about months with varying numbers of days. Plus it had the convenient effect of putting every date, every month, every year on the same day. The third of the month is *always* a Tuesday. The 20? Always a Friday (and yes the 13th too). The original proposal also moved holidays to where they were always on Monday. \n\nFor those wondering, the extra month was called Sol and it was in the summer (obviously). And for those of you who did the math, we got a December 29th. A holiday called year day. "
]
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||
13anho
|
Is dandruff really related to your water and how hard/soft it is?
|
I am wondering because 1. I've always heard this growing up and 2. Now that we live in a new home that is one a well and barely get any hard water deposits, my entire family has been having problems with dandruff and am wondering if some of those filtered shower heads might do the trick or not.
|
askscience
|
http://www.reddit.com/r/askscience/comments/13anho/is_dandruff_really_related_to_your_water_and_how/
|
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"Well there are lots of causes for dandruff actually.\n\n_URL_0_\n\nNow this only lists medical reasons for dandruff, but we can already see it is a complex problem.\n\nWe know hard water is caused by a high amount of minerals dissolved into the water. We can see this by placing water on a black plate and allowing it to evaporate and observing the white/yellow residue left behind.\n\nThis same residue is left on your hair and scalp. \n\nIt usually would cause a fine powdery dandruff vs large flakes though.\n\nHad water also causes soap to not lather properly leaving soap scum behind. This us also harder to rinse off properly. _URL_1_\n\nTry rinsing better or using white vinegar just before you get out of the shower. Dont worry it will dry odorless.\n\n "
]
}
|
[] |
[] |
[
[
"http://www.mayoclinic.com/health/dandruff/DS00456/DSECTION=causes",
"http://en.wikipedia.org/wiki/Hard_water"
]
] |
|
usy6b
|
What causes that sound my laptop makes when I am loading something?
|
I never really thought about it until right now, when I booted up Minecraft. I thought it was all wires and chips inside my computer. The only noise that would make sense is the fan, but I'm not talking about fan noise. I'm talking about the unique sound that kinda sounds like bugs squirming around or something.
|
askscience
|
http://www.reddit.com/r/askscience/comments/usy6b/what_causes_that_sound_my_laptop_makes_when_i_am/
|
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"It's most likely the hard disk drive you're referring to. It contains a metallic disc that rotates very quickly, and a magnetic head retrieves and writes data to it. They contain a small motor to drive the disc and the process causes some noise (a clicking or crunching sound).",
"There are two motors inside a hard drive. The spindle motor makes a constant relatively quiet noise. The other is the \"voice coil\" which makes angular movements of the read/write heads. This is what makes the chattering noise you are referring to. Often, data are widely distributed over the disk surface and not accessed sequentially, meaning the read/write head assembly moves to many hundreds of different locations per second."
]
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|
[] |
[] |
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[],
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|
fabqp7
|
what does 'dry' mean in alcohol
|
I've never understood what dry gin (Gordon's), dry vermouth, or extra dry beer (Toohey's) etc means..
Seems very counter-intuitive to me.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/fabqp7/eli5_what_does_dry_mean_in_alcohol/
|
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"Imagine you worked at an ice cream shop.\n\nYou have 3 main types of ice cream.\n'Lip-smacking' sweet, 'Lemony-fruity' sorbet, and 'Cool-down' mint. \n\nIt can get a little tricky to explain minty flavours to customers, as there's a fine line for what some people may identify as 'cold' (which all ice cream is) and the cooling flavour of say, 'peppermint'. To communicate a little more effectively on the difference, it may be easier to have a different flavour identifier, in this case maybe...'cold-spicy'?\n\nThe term 'dry' in the drinks industry is similar to this in the sense that, in many cases, 'dry' simply refers to the more pronounced evidence of 'alcohol' flavour. The most well-known example of this is when ordering a 'Martini' cocktail. Asking for a dryer Martini just communicates that you like a higher ratio of alcohol vs the other additives (water & vermouth). Similarly, with white wine, a dryer tasting wine usually is an indication of the lesser amount of sugar levels of the wine prior to bottling. As all alcoholic beverages contain ethyl alcohol, the term 'dry' helps define the more clear & crisp flavour in certain 'boozy' flavoured drinks. \n\nThis is a very simplistic explanation, and misses out a lot of detail in the realm of sensory profiling in the biz, but it's a base understanding of how the term is used. \n\nSource: bar guy",
"In a very simplified way it refers to how sweet or, in this case, not sweet a drink is. A dry drink is not going to have much sugary (or fruity - another term used) taste in the mouth. \n\nSo a fruity drink is sweet while a dry drink is not sweet to the taste.",
"dry is the term used to describe the sensation of alcohol evaporating off of your tongue. It's generally the opposite of sweet.",
"Fully dry (“brut”) means the yeast have converted all available sugar to alcohol, leaving little/no residual sugar. A brut beer still has some residual sugar, and this is because yeast can’t eat maltose (malt sugar). In contrast, the sugar in fruit alcohol (cider, wine, champagne, etc) is fully digestible to the yeast, so a brut wine will have no residual sugar.\n\n*EDIT - other redditors have made right what I got wrong in the comments below. Here's a fresh take at the point I was attempting to make: It is a challenge to produce a fully dry maltose-based alcohol (e.g. beer) because the yeast will naturally cease activity before all sugar is consumed. Conversely, it is a challenge to produce a sweet or semi-sweet fructose-based alcohol (e.g. cider) because the yeast will generally be active until all sugar is consumed.",
"As the other commenter said, it's essentially the opposite of sweet. Dryness refers to how much of the sugar has been converted to alcohol. The drier it is, the less sugar left after the fermentation.",
"A few people have touched on a few accurate points here but dry can have several meanings, when it's in regards to a white wine or a rose it is generally a reduced sweetness due to the variety of grape and when it is harvested, with a red wine it is generally the tannin content that has the drying effect in your mouth,\n\nA dry gin can be two things, a London dry gin, which is a classification of gin not necessarily due to the sweetness, it's related to the distilling and steeping process involved in creating gin, whereas a non London dry gin that is dry is related to sweetness and mouth feel.\n\nDry cocktails are a combination of sweetness tasting, potentially tannin content, and acidity, but is a combination\n\nIt's a bit more complicated than this but this is the general outline for your average consumer\n\nSource; bartender for 3 and a bit years at nice venues",
"It very much is the opposite of sweet. But one thing I also like to mention is that it is so the opposite of sweet it feels dry. Its taken me a long time to like dry wine because it feels counterintuitive on the tongue. This liquid makes your mouth quite literally feel dry thats how unsweet it is. It certainly isn't bad and once your used to it is pretty good actually but its different for sure.",
"Wow, this was a rabbit hole - but I did some research.\n\nFirst, the meaning is pretty easy (and covered) - dry alcohol means not sweet. (London Dry Gin is a different story I'm not going into). So, if you see a wine or beer or alcohol listed as dry, there is usually a sweeter counterpart.\n\nBut, why \"dry\" to describe \"not sweet.\" The best answer I've been able to find is that we can trace the term centuries back - to the extent you need to look at french text from the 1200s for the first recorded references to \"vin sec\" (dry wine). When terms are that old, you usually loose the etymology - so all that is left is our best guesses.\n\nOne very good thought is that wine used to not be aged the way it is now. We lost the art of tightly sealing jars (perfected by Greeks and Romans) in the dark ages, so if you let wine age too long it would go bad. Aging is one way we can breakdown the chemicals that make a wine astringent. If you drink a very astringent wine, you will notice your mouth feels dry. Sweet wines (wines with more sugars in them) mask the astringency and would not have a dry mouth feel. As different ways of making wines and alcohols evolved in the ensuing centuries, we were able to make not-sweet alcohols that don't have this effect, but the term \"dry\" stuck.\n\nFor more extensive reading with lots of links: [_URL_0_](_URL_0_)",
"Yo! After panning through the replies, I figured I'd drop some thoughts here. Source: I am a Certified (edit: now Advanced!) Sommelier and a Certified Specialist of Spirits.\n\n**Dry, as some have mentioned, is the word used to describe the opposite of sweet.** I will reference a few laws below that use this definition in legal practice to confirm this as the internationally accepted, and in many cases, legally-binding definition.\n\nWater is dry. Add sugar to it and it has some level of sweetness. You might hear words like \"off-dry\" to describe a small amount of sugar, \"semi-sweet\" a bit sweeter yet, and \"sweet\" or \"lusciously sweet\" to describe things even sweeter still. These are typically used to describe ranges of sugar expressed in **grams of sugar per liter**, which, if you multiply by bald eagles and divide by original colonies, can be converted to American. ;)\n\nFor reference, Coca-Cola has \\~126g/L of sugar. It's what most industry folk would call something like \"sweet\", \"cloyingly sweet\", or \"lusciously sweet\". [Source.](_URL_1_)\n\nThe amount of sugar in a wine can typically be found (except by many American producers) by searching google for \"(insert wine name here) tech sheet\". For example, find the technical notes for Moët & Chandon Imperial Brut [here](_URL_0_), where sugar is listed under \"dosage\" to be 9g/L. Keep in mind that most bottles encountered in the wild are 750mL, so to obtain a sugar level per bottle, simply multiply by .75.\n\nA few laws for describing dryness, for the purpose of confirming the above definition:\n\nGerman wines are allowed to call their wines \"trocken\" (dry in German) if and only if the wine has 9g/L of sugar or fewer.\n\nVouvray, a wine-making village along France's Loire River Valley, only allows for their wines to be labeled \"sec\" (dry in French) if the wines have 8g/L of sugar or fewer.\n\nSee below for a law on Gin.\n\n & #x200B;\n\n**Common misconceptions:** \"Dry\" is often used by consumers to refer to the drying sensation one experiences after taking a sip of a beverage. This is a mistake, because the technical word to describe that sensation is \"bitterness”, while the word most often used to describe the bitterness coming from grape and oak tannins is “tannic”. However, most beverage professionals (assuming they're paying attention) are in tune with the fact that this misconception is quite prevalent, so an astute salesperson should respond to \"I'd like a dry wine\" with something to the effect of \"Dry as in 'the absence of sugar' or dry as in 'dries my mouth out'?\"\n\nThe word \"tannic\" describes the sensation of astringency brought on by tannin, a compound--long name polyphenols--found in grape skins. Red wine, which is colored by leaving the crushed grape skins in the juice until the color seeps out--think of a tea bag leaching out its color--are prone to having tannin by the nature of this process. The longer the skins stay in the juice (sometimes as long as several weeks) to color, flavor, and add texture to the wine, the more tannin will be extracted from the skins, and the more the wine will dry your mouth out. But, again, this is not \"dryness\" technically, this is tannin--polyphenols--binding to your saliva and leaving a drying, sandpaper-like, cottonmouth feeling. Tannin can also be found in such things as tea leaves. Think over-steeped tea.\n\n & #x200B;\n\nAbout things like gin specifically, London Dry Gin is a spirit which must, by law, be flavored predominantly by juniper and have no more than .1g/L of sugar. This level of sugar is what the industry folk would call \"bone dry\". Keep in mind that this is different from \"Dry Gin\" and simply \"Gin\", which are principally made the same way (by flavoring a neutral spirit) but may have different interpretations of flavors and different levels of alcohol and sweetness.\n\n & #x200B;\n\nDryness is also distinct from alcohol content in terms of organoleptic qualities, though high levels of alcohol can change the mouthfeel (especially adding viscosity, a liquid's resistance to flow or \"thickness\") and add a perceived sweetness--a bone dry liquid with the viscosity of maple syrup may seem sweeter to the taster than a bone dry liquid with the viscosity of skim milk simply by perception, even though the two liquids in question have the same amount of sugar.\n\n & #x200B;\n\n**A word of caution:** As alluded to above, many wines and spirits are regulated by law in their production. Those which are not so regulated (American products, and products of countries who don't have bi-lateral trade agreements with countries who do regulate these things) are a great deal more laissez-faire when it comes to what words and designations end up on their products. A wine labeled \"dry\" in the states has no required limit of sugar. It could have 200g/L and face no legal recourse for naming it as such. Do your research on wines if you have any questions!!\n\n & #x200B;\n\nHope this is helpful! Happy Thursday!",
"I’m a home brewer who occasionally also makes mead and wine so here’s my crack at it:\n\nAll booze starts off as super sweet sugary liquid. Yeast eats most sugars and poops alcohol. The more sugar that has been converted to alcohol, the “drier” the drink.",
"As everyone said, dry = not sweet. \n\nWith vermouth, dry vermouth is a whole different product than sweet vermouth. Sweet vermouth is normally dark, and dry is normally a white vermouth.\n\nOr, if you’re talking martini, dry means less vermouth. In this sense you’re thinking of “dry” vs “wet.”\n\nSource: bartender",
"Lots of talk about wine but I havent seen how it applies to beer mentioned so Ill take a stab at it. \n\nYeast eats sugar and makes alcohol. Malted barley (pre-beer) is sugar. Sometimes the yeast cant eat all the sugar and some is left. This leads to 'residual sweetness'. Think Russian imperial stout maybe?Sometimes the yeast eats all the sugar available and leaves a 'dry' beer like in a brut IPA. Sometimes a non-fermentable sugar (lactose) is added like in a milk stout. This also leaves a sweeter taste. \n\nOriginal gravity (O.G) Vs Final gravity (F.G.) is a helpful way to see this. O.G. is a measure of the sugar in a wort (pre-beer) available. F.G. is a measure of the amount of sugar when fermentation is finished. The higher the F.G. the sweeter the beer, the lower, the more alcohol and dryer the beer. Roughly.",
"In terms of actual chemistry, dry ethanol is ethanol with very little water. As both molecules are polar, they mix very readily. Removing water from ethanol can be done via distillation, followed by adding Magnesium Sulfate. It may be needed to dry ethanol if left open for a while when you need a pure ethanol solvent. This is not the same term as 'dry' when referring to an alcoholic beverage however - I believe in that context it refers to the flavour of the beverage.",
"If you are wondering \\*why\\* unsweet alcohol is characterized as \"dry,\" it actually goes all the way back to Hippocrates. He observed that people who drink too much wine could become dehydrated, and he also noted that the consumption of alcohol often brought a feeling of warmth, so he thought of wine as being both dry and hot, relative to other liquids. The \"heat\" of wine had nothing to do with its temperature (just like its \"dryness\" was unrelated to its liquid state), but rather with some sort of internal quality that is evidenced by what happens when you drink it.\n\nNoting that the sweetness of a wine inversely correlates with its suppressive effect on salivation, acrid wines were described as more ‘dry’ than sweet wines. \n\nFor ultimately similar reasons, we can refer to certain kinds of comedy as \"dry\" -- deadpan delivery lacks the outward signs of cheer associated with blood, which he thought of as particularly wet -- or as \"dark\" (associated with \"black bile,\" melan choler, from which we get the word melancholy).",
"Dry just means not sweet, as in the lack of sweetness. Something that is dry usually either contains less sugar or has some ingredients or flavors that hide the sweetness.\n\nThat is why the 2 varieties of vermouth are sweet and dry or sweet and not sweet.",
"Dry means no residual sugar.\n\nAlcohol is made by yeast consuming sugars and producing alcohol plus carbon dioxide. A “dry” product is one where the yeasts were allowed to consume all sugar. Semi-dry, semi-sweet or sweet are the other options, all based on the remaining sugar content. Yeasts will continue to consume sugars as long as they exist so to make a semi sweet product for example you have to either kill the yeast (arrested fermentation) or allow it to ferment to dry then remove the yeasts and then back sweeten with sugar or fruit juices.\n\n(I work at a cidery)",
" Dry as in the opposite of sweet. Less sweet, and more of the other flavors. The sweet can only be less, there is no actual literal opposite to it, it's just that the other flavors counterbalance the sweet.\n\n & #x200B;\n\nThe most obvious opposite of sweet is sour\n\n & #x200B;\n\nBut there is also astringency. That pucker the back of your tongue taste. Sumac has this taste, for comparison.\n\nSome bitterness also often comes along with the astringency, and is also part of the \"opposite\" of sweet\n\nAn astringent is something that constricts tissues. Witch Hazel, which you can buy OTC at any pharmacy, is an astringent. There are things in certain fruit juices and I think botanicals that are astringent that you taste. Since it constricts the tissues on your tongue, it literally feels like it's trying to dry out your tongue.",
"Bartender here, just wanted to add a few things to the glorious comment from our resident som and spirits expert. \n\n\nAs far as London dry gin goes, that’s the title of one of five different types of gin. London dry is the most regulated and has very specific parameters it must conform to in order to be labeled as London dry. The other gin types are old Tom, genever, contemporary, and plymouth. You can think of these in terms of whiskey if that helps. For example, both bourbon and scotch are whiskeys, but they have very different requirements to be labeled as such. \n\n\nSimilarly, dry vermouth is a type of vermouth, or fortified wine. There are other types of fortified wine which may or may not be called vermouth, such as cocchi americano or blanc vermouth. The other most popular vermouth is sweet vermouth, which gets its name from the burnt sugar present in most sweet vermouths. You’ll find dry vermouth, the straw colored stuff, in a martini, and you’ll find sweet vermouth, the brown stuff, in a Manhattan. \n\n\nCheers!\n\n\nEdit: it’s also very popular to order a “dry” martini. In that context, what the guest usually means is that they want a martini made with less dry vermouth. It’s frustrating and extremely counter intuitive, but that’s the typical nomenclature used by the average consumer.",
"I believe it has to do with having less or no residual sugars or the lack of the ability of the palate to detect them. Sugar tend to round the mouth feel of a drink make it \"softer\" on the palate.\n\n non expert but I took a wine class in school so take this with a grain of salt.."
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2wsusd
|
How did currency work in the Soviet economy if it was a command economy?
|
I am aware of Gosplan (the Soviet economics bureau) but I am curious how currency factored into the system, and how the Soviets dealt with problems of inflation, commodities/currency exchanges (I am aware they had price controls) and banking.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2wsusd/how_did_currency_work_in_the_soviet_economy_if_it/
|
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"Under a price fixing system you didn't have to deal with inflation you don't want because you (the government) set the price, thus by definition you didn't have inflation (outside of the black market anyway) if you don't increase prices. Instead, the problem you had to deal with were shortages (as the Soviet Union actually have to deal with) because prices don't adjust. Note that this wasn't always the case and there were bouts of inflation in the Soviet period, but unlike in a market economy, you could always just fix prices to avoid it and exchange the problem of inflation for the problem of people waiting in long lines to buy consumer goods.\n\nThe banking system was completely state ran, capital allocation was done through the bureaucracy. Household savings etc would be handled by the Sperbank, Investment was handled by the Stroibank, and another bank ran foreign exchanges. Above those you had the Gosbank, which was the core of the state banking system. In effect, the USSR had a single state ran banking monopoly.\n\nMoney sort of mattered when you are dealing with the consumer economy, workers were paid in wage, and bought goods in wage. However, cash didn't factor into the equation when you start talking about exchange between enterprises. If enterprise A transfers raw material to factory B for use, the Gosbank would oversee the process and credit A's account while debiting B's account without direct exchange of money between those two entities.\n\nOne implication of this is, of course, that inter-enterprise lending is not allowed because there is no mechanism for it except through barter (which did take place). Enterprises in the Soviet Union were forbidden from holding onto cash except paying worker's wage.\n\nForeign trade was conducted through the Vneshtorgbank. An enterprise producing trade goods would first sell it to the Vneshtorgbank, which would then credit its account, then sell it to foreign countries for hard currency. Which it would then hold on to until it needs it to buy foreign imports, which it would do with the foreign currency it holds. Then it will sell the imports to a Soviet firm, debiting and crediting accounts as needed in the process."
]
}
|
[] |
[] |
[
[]
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|
2gu59s
|
With Scotland's rejection of independence is there any other British territory/colony that did the same in history?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2gu59s/with_scotlands_rejection_of_independence_is_there/
|
{
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"Newfoundland was offered the opportunity to become a dominion with the Statute of Westminster 1931. This would have given it free self-rule in its domestic matters, basically just leaving it allied and in a privileged trading position with the United Kingdom and the other dominions, which included Canada, Australia, New Zealand, and South Africa. A series of financial crises and near-bankruptcy caused Newfoundland to reject this arrangement, and its parliament requested that the British take up direct rule from London, which continued until it became a province of Canada in 1949. ",
"Gibraltar has a unique governance structure, being officially a British Overseas Territory governed by a governor who reports directly to the British Crown. The UK government has responsibility for defense, external affairs and monetary policy, but the territory is self-governing internally and is an independent member of the EU. \n\nSpain continues to claim sovereignty over Gibraltar, but a proposal in 2002 for the two nations to share sovereignty (an international arrangement known as *condominium*) was rejected by the voters of Gibraltar, with 98.48% of voters voting no. \n\nThere is a movement in Gibraltar politics to form closer ties with the UK, possibly by incorporating into the UK itself, which would mean Gibraltar electing representatives to the British parliament, but I won't go into that too much because of the 20-year rule (which I have already overstepped by talking about the 2002 referendum). ",
"Only a couple colonies have given up/avoided offers of self rule, and all were due to economic and political turmoil. As already mentioned Newfoundland was one, but the Caribean colonies as well gave up self-rule. \n\nWhite planters were given legislative assemblies of varying kinds in the early 19th century, however with the abolition of slavery and the crash of the sugar industry they gave up self-rule some 70 years later. London ruled the Caribean through unelected Govenors/commissioners until the 1940s-50s when varies nationlist movements that were separate from the planters arose. \n\nI think it is worth noting that the Scots are one of the few members of the Empire who have been given a straight yes/no question on their participation. The overwhelming majority of colonies became independant through negotiations between London and representatives of some kind - be their nationalist movement leaders like Gandhi and Kenyatta, or Parliamentary leaders like John A MacDonald, Smutts, or Billy Hughes. Even the Irish, with their tradition of violent uprising negotiated the Anglo-Irish via a delegation from the Second Dail. \n\nI can not think of a single commonwealth member that has become independant directly because of a referendum. (And I would apperciate help finding one)\n\nSource: Canadian history undergrad, third year course in british history, stanley walports a new history of india. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
6hxaha
|
How many times can a piece of plastic be recycled?
|
askscience
|
https://www.reddit.com/r/askscience/comments/6hxaha/how_many_times_can_a_piece_of_plastic_be_recycled/
|
{
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"text": [
"This is highly dependent on how you want to recycle the plastic and the plastic material itself.\n\nA thermoset plastic is a non-reversible process, so it can't be used as re-grind in an injection molding process, whereas a thermoplastic may be able to be used depending on the performance required. Each time to process a thermoplastic it loses some of its properties, as well as potential effects on fillers. \n\nYou can also recycle plastic as an aggregate such as in products like extruded plastic lumber. Plastic isn't fully melted in the process, and the performance isn't as critical, so you can theoretically recycle the plastic more times."
]
}
|
[] |
[] |
[
[]
] |
||
3xsy3o
|
when igniting a flammable substance from a gas canister, why doesn't the flame travel inwards towards the source and blow up the gas canister
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3xsy3o/eli5_when_igniting_a_flammable_substance_from_a/
|
{
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"text": [
"you need oxygen/fuel at a minimum ratio to combust. There is little or no oxygen in the gas canister.",
"Because the gas canister is pushing the gas out and away, there is also no oxygen inside the canister, which prevents the gas inside from catching fire.\n\nIf you put a gas canister (with the valve shut) into a fire, two things could happen:\n\n* Some canisters (especially in laboratories) have security valves that open when there's too much pressure, the heat makes the gas inside expand, so the valve opens and releases the gas, it catches fire.\n* The gas inside keeps expanding untill the entire canister explodes, this is by far the worst alternative.",
"For some gases and liquids that CAN happen. Like ethylene oxide or nitro methane as examples. In fact they have to use detonation traps.\n\nOn nitro methane:\n_URL_0_\n\" The employer did not protect its employees from the recognized hazard of fire and explosion in that pipes, one-half inch or greater in diameter containing nitromethane and/or a nitroethane mixture, located in pipe racks in the nitroparaffin plant were not equipped with detonation traps.\"\n\nOn ethylene oxide:\n_URL_1_\n"
]
}
|
[] |
[] |
[
[],
[],
[
"https://www.osha.gov/pls/imis/establishment.violation_detail?id=107607863&citation_id=02067",
"www.aidic.it/lp2013/webpapers/213reza.pdf"
]
] |
||
bvw2zq
|
Was there a sort of international court dialect used between European monarchs in medieval times, or were there just a lot of translators
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/bvw2zq/was_there_a_sort_of_international_court_dialect/
|
{
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"text": [
"Okay, there were a couple of different things going on here. In the first place, we need to remember that monolingual inhabitants of monolingual nation-states is a comparatively recent notion. Medieval Europe was a giant quilt of different competing dialects, pidgins, creoles, and languages. As a result, aristocrats especially would frequently be fluent in several other languages. It's now time for a block quote because Tyerman said the next part best.\n\n > Learning to speak, even read, other languages came as less of a burden to twelfth-century western aristocrats than to some of their modern successors. In addition to his own local vernacular, an educated nobleman would have daily confronted Latin (if only in church or at prayers) and probably numerous other vernaculars, if only orally. Henry II of England was fluent in northern French and Latin, with a smattering of other western European languages; his son Richard I cracked jokes in Latin and recited verse in northern and southern French. To rule England or Sicily, Norman rulers or their officials needed to be trilingual. (Tyerman 234).\n\nIn addition, French was something of a *lingua franca* among Western European aristocrats and also your mercantile classes. If you look at Wolfram von Eschenbach's *Parzival*, you'll see that he occasionally drops a bit of French in to show his courtliness. Basically, French in the twelfth through fifteenth centuries had a status among Western European elites very similar to that of English among global elites today. For a good example of how French culture especially affected German aristocrats, I'd recommend a look at Joachim Bumke's *Courtly Culture*, my copy of which seems to have grown legs.\n\nIn my own neck of the woods, namely thirteenth-century England, you see an aristocracy that almost certainly spoke the Anglo-Norman dialect of French and also English. Richter and Rothwell have pretty convincingly shown that within about a generation of the 1066 Norman Conquest most English nobles spoke English as their first language. In the first half of the thirteenth century, your aristocracy was probably fully bilingual. By contrast, by the second half of the thirteenth century, we can get a sense that your nobility might have been more comfortable in English than with French (Crane 110). Even so, elites were more comfortable with French than Latin, and that holds true even at the rank of the parish priest (Richter 190).\n\nThere's some evidence of French as a living language even in fourteenth-century England (see, for example, Richard Ingham's “The Persistence of Anglo-Norman, 1230-1362,\" but we're on pretty firm ground to say that by the later fourteenth century your English aristocracy was mostly Anglophone but more or less fluent in French as a learned language.\n\nSidebar: even as early as the late twelfth century, the term \"Marlborough French\" -- a sneer for the French of England -- could be used as a punchline by someone like Walter Map, the raconteur who wrote *De nugis curialium* (*On the Trifles of the Court*).\n\nDoes that answer your question?\n\n**Sources**\n\nBumke, Joachim. *Courtly Culture: Literature and Society in the High Middle Ages*. Translated by Thomas Dunlap. Los Angeles: University of California Press, 1991.\n\nIngham, Richard. “The Persistence of Anglo-Norman, 1230-1362.\" In *Language and Culture in Medieval Britain: The French of England, c. 1100 – c. 1500*, edited by Jocelyn Wogan-Browne *et al*, 44-54. York: York Medieval Press, 2009. \n\nRichter, Michael. *Sprache und Gesellschaft im Mittelalter: Untersuchungen zur mündlichen Kommunikation in England von der Midde des 11. bis zum beginn des 14. Jahrhunderts*. Stuttgart: A. Hiersemann, 1979.\n\nRothwell, William. \"The Teaching and Learning of French in Later Medieval England.\" *Zeitschrift für französische Sprache und Literatur* 111 (2001): 1-18.\n\nTyerman, Christopher. *God's War: A New History of the Crusades*. Cambridge, MA: Belknap, 2006."
]
}
|
[] |
[] |
[
[]
] |
||
76xnq6
|
- are speed bumps designed to damage your car if you go over them too fast?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/76xnq6/eli5_are_speed_bumps_designed_to_damage_your_car/
|
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"Some are, yes. We have the normal speed bumps but there is a whole road nearby that uses ~~his~~ these rubber things bolted down and even if you are going really slowly the jolt they give you is enormous. ",
"every time you drive your car, yes, the suspension will suffer wear & tear. If you hit bumps like they weren't there, you will just wear out the suspension a bit sooner.",
"If you hit them too fast, the suspension will pack down and you risk smacking the front plastics of the car into the ground. \n\nProperly shaped and sized speed bumps shouldn't do any damage as long as you slow down enough.\n\nMost speed bumps should be driven over at less than 20mph. ",
"Speed bumps are intended to force drivers to slow their speed. Most are designed in such a way to make it uncomfortable for the driver to take them too fast, but are not intended to damage their vehicle. Others are poorly designed and *will* damage the vehicle, even at a reasonable speed. Even properly designed speed bumps can damage a vehicle if the vehicle is going much too fast, though.\n\nThe wear and tear you experience going over a speed bump is negligible. You'll experience more wear and tear through simple road driving because you do more road driving than you spend time driving over speed bumps.\n\nThing to remember about speed bumps is this: the speed that it is safest to driver over the speed bump is the speed you are supposed to be driving on the road even where there are no speed bumps. If you are going 45 mph, then slow down to 25 mph to go over the speed bump, accelerate back up to 45, slow down to 25, again to go over the next speed bump, you are doing it wrong. You should be traveling 25 up to the speed bump, over the speed bump and between the speed bump. The city likely placed the speed bump on that road because drivers are travelling that road too fast.",
"Square edge bumps (rough roads, potholes) will wear your suspension out faster than speed bumps because these are felt as impacts that are transmitted to the bushings in your suspension. \n\nSpeed bumps are smooth, they are soaked up by the normal travel of suspension and are not jarring impacts. As long as you are not bottoming out your suspension by going over them too fast (felt as a clunk) they will not hurt your car. ",
"No, speed bumps are designed so that if *you* drive over them too fast, *you* will damage your car. ",
"Let me tell you a story;\n\nBack in college I got a ride with this guy from my class, cool guy but thick, there were 5 of us in the car and 2 Lads were goading him in to speeding.\n\nThen they saw a speed bump and one guy said “I bet you can’t get air off that speed bump”. This guy goes full pelt into a speed bump trying to get air, as soon as he hit the speed bump the front of his car disintegrated. It felt like I’d been smashed by a truck, the whole front end of his car was all jacked up and so were our bodies.\n\nSpeed bumps are designed to act more like a wall the faster you go, so yeah they are designed to destroy your car unless you take them slow.",
"When you hit a speed bump too fast, it causes the suspension to compress in a very short amount of time, which generates high peak forces in the suspension that can damage seals and bushings. It's all about the mass, the displacement (speed bump), and speed. Increasing any of those will increase the impulse. Increase the impulse too much, and stuff will break.",
"In portuguese, speed bumps are called \"quebra-molas\". roughly translated, it means \"suspension-breaker\". So yes, I think so."
]
}
|
[] |
[] |
[
[],
[],
[],
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[],
[],
[],
[],
[]
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||
2ofah9
|
the purpose of the recent orion flight and what it means for both future space exploration as well as nasa itself?
|
I have been very into the whole Orion launch, but then I saw the flight path which was just a single orbit around the planet; don't we have satellites that do that everyday? Did we not make this feat years ago? I must be missing something here, please enlighten me!
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2ofah9/eli5_the_purpose_of_the_recent_orion_flight_and/
|
{
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"text": [
"It was to first test out if the Orion was safe for human Flight. If something went wrong with the capsule, they could use the data to avoid astronauts being killed.\n\nAs far as the future is concerned, this can really mean anything. NASA is currently planning to use this series of vehicle to transport humans to mars, and to set up a colony there. For the expedition participants, it will be a one way trip.\n\nThe Orion is designed to be able to dynamically attach to a lot of different add ons, like a larger living area on long expeditions, using the same example as mars.\n\nIn the future, this may be used as what brings astronauts to iss, since its reusable and cheaper than space shuttle to maintain. The rockets designed to launch it with(not this test flights, this time they used delta IV heavy; the actual one is still in construction) will allow deep space exploration line never before due to its massive thrust.\n\nSo really, in short it means manned space exploration and colonization."
]
}
|
[] |
[] |
[
[]
] |
|
3i7bpg
|
Any good sources on the illegal smuggling of slaves into the US in the 19th Century?
|
I'm staying on a group of islands off the Georgia coast that claim the last shipment of smuggled slaves arrived in 1865. It has piqued my interest about slave smuggling. Who was involved? How profitable was the trade? What happened to those who were caught?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/3i7bpg/any_good_sources_on_the_illegal_smuggling_of/
|
{
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"text": [
"You could look into the De Wolfe family, of Rhode Island. Slavers, congressmen, financiers of the Episcopal church in RI.\n\nThe New York Times just came out with an article on Rhode Island's role in the illegal slave trade:\n\n_URL_0_\n\nThere is a great documentary from a few years back, which won awards and I'm pretty sure was played on PBS, called Traces of the Trade, which also follows the De Wolfe family. My favorite part is when they get a map of the family's holdings in Cuba post-Civil War and figure out that they still owned slaves, but in Cuba instead of in the US:\n\n_URL_1_\n\nAn amateur historian named Cynthia Mestad Johnson wrote James Dewolf and the Rhode Island Slave Trade based on primary sources in the Rhode Island archives. That book is on Amazon.\n\nI'm no specialist in the illegal slave trade myself so I can't give you more than that. Sorry. I just know about these guys because they had links to Cuba, which is my field of study.\n\nEdit: Damn, I read your principle question but not so much your follow up questions. Here goes:\n\n > Who was involved? \n\nDirectly, major figures in much of the US, including the North. The De Wolfe family was one of the single most important families of its state and were able to do so with impunity. I'm sure their case isn't the only one.\n\n > How profitable was the trade? \n\nProfitable enough to make the De Wolfe's one of the richest families of their time. The wealth also found its way into the local economy where the slavers lived. The slavers would buy irons from local blacksmiths, rope from rope makers, food stores from local farmers, etc., and thus these would indirectly partake in the immense gains that slavers would make.\n\nEric Williams spoke of a similar phenomenon occurring in English cities, like Liverpool, in his book Capitalism and Slavery, but with the difference that it was at least legal when English slavers were doing it in the 17th and 18th centuries.\n\n > What happened to those who were caught?\n\nOn this point I am totally ignorant. Perhaps a specialist in the American slave trade could answer this better."
]
}
|
[] |
[] |
[
[
"http://www.nytimes.com/2015/08/24/us/rhode-island-church-taking-unusual-step-to-illuminate-its-slavery-role.html?emc=edit_th_20150824&nl=todaysheadlines&nlid=65658439",
"http://www.tracesofthetrade.org/"
]
] |
|
tjtmh
|
Is it true heavier people require more alcohol to get drunk.
|
Example: If you lose a lot of weight would you get drunk quicker? Or is it mainly just a person to person thing?
|
askscience
|
http://www.reddit.com/r/askscience/comments/tjtmh/is_it_true_heavier_people_require_more_alcohol_to/
|
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"It has to do with body weight, stomach content, gender and genetics. reducing your body weight could have an effect, but it would be easier to just start drinking on an empty stomach if you were trying to get intoxicated, and eat beforehand if you were trying to avoid it. \n\nBut yes, if you lost Lot of weight, it could have an effect, just not a gigantic one \nEDIT: spelling",
"I believe a major factor has to do with total body water, something that I believe would change with the fat content of a person. \n_URL_0_ - \"Total body water volume (TBW) is one factor that determines the functional effect of a standard dose of alcohol. Because women and the elderly generally have lower TBW values than men and younger persons, respectively, less alcohol needs to be consumed by women and elders to achieve the same or higher blood alcohol levels compared to men and younger persons.\"",
"Tangentially related question, but do fatter (obese) people have more blood? "
]
}
|
[] |
[] |
[
[],
[
"http://www.ncbi.nlm.nih.gov/pubmed/7780299"
],
[]
] |
|
9xn1ks
|
The new kilogram definition seems complex. Why not define it in terms of the mass of a proton?
|
The kilogram is being redefined.
[_URL_0_](_URL_0_)
The new definition is in terms of the Planck constant and seems complex (or at least not very elegant.) Why isn't the kilogram defined as something simpler like the mass of X number of protons?
|
askscience
|
https://www.reddit.com/r/askscience/comments/9xn1ks/the_new_kilogram_definition_seems_complex_why_not/
|
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"text": [
"It is not possible to precisely collect X protons under conditions that it could be used for a standard of mass. You could try for example saying that a kilogram is the mass of (0.1 m)^3 of water, but then you'd have to control precisely for temperature, pressure, isotopic composition, etc in a way that is precise to 10 parts per billion. The new Planck's constant definition is sufficiently precise.\n\nThere was an attempt to do as you suggest, and make it based on the [number of atoms in a very pristine sphere](_URL_0_), but it wasn't as practical as the Planck's constant way.",
"That was - kind of - the alternative approach, where the kilogram was going to be defined via the Avogardo costant and the mass of a set number of silicon atoms. In practice it was shown that counting atoms accurately is not that easy, and finally the Kibble balance was chosen. \n\nSee here for more details: _URL_0_",
"The new definition, based on Planck's constant, is actually *more* elegant than the previous definition (which actually was similar to what you are describing, a relationship between subatomic particles and weight) because it is defined with a few of the known constants in the universe.\n\nMany measurements and observations are relative. They depend on factors like where the object is that you are measuring, or from what direction or speed the object is being observed. Gravity is like that, so is speed. Things that *aren't* like that are the speed of light and the charge of an electron. So this means a kilogram, as newly defined, more precise than ever before and shouldn't change anywhere in the universe. \n\nFor lots of everyday observations, nothing will change, but for very precise calculations, like orbits of stellar bodies and weights of tiny doses of medication, it will help us make better predictions. ",
"The mass per proton changes depending on how many of them you have together due to binding energy. As a result 2 protons individually have more slightly mass than if they were bound together. This makes them very bad for using as a metric since the mass of the proton is not a constant but varies depending on it's interactions with other particles. ",
"\"Why not define [a kilogram] in terms of the mass of a proton?\"\n\nThe goal is to define a basic unit of mass that everyone can use. In theory, it doesn't matter whether that unit is kilogram-sized or proton-sized, or < Avogadro# > -protons-sized. However, in practice, you want to be able to define that unit of mass from the results of a repeatable experiment, so that everyone around the world can use as close to the same value as each other. The goal is maximum consistency.\n\nSo you can't just say that the unit is the mass of a proton, because not many people can measure that directly. If someone wants to say how much mass of a chemical they used in a reaction, well they can't really count up the protons very easily. With the old method, where the unit was the mass of the standard Kilogram artefact, you can measure that directly (with a set of scales, or something fancier).\n\nThe new method avoids (directly) measuring the mass of anything. All you need to do is measure the time of a second (based on easily-measurable atomic clocks) and the length of a meter (based on somewhat-easily-measurable speed of light). You also need to know the Planck constant, but as long as everyone uses the same constant (which they will because it gets standardized when it comes to base unit calibration), then everyone's mass measurements will match just as closely as their time and distance measurements matched."
]
}
|
[] |
[
"https://www.vox.com/science-and-health/2018/11/14/18072368/kilogram-kibble-redefine-weight-science"
] |
[
[
"https://www.nist.gov/si-redefinition/kilogram-silicon-spheres-and-international-avogadro-project"
],
[
"https://www.nist.gov/si-redefinition/kilogram-silicon-spheres-and-international-avogadro-project"
],
[],
[],
[]
] |
|
1fu0tc
|
How do millipedes walk?
|
As I was leaving work today, I became fascinated watching a millipede climb on some rocks. It looked like its legs were moving in a wave-like pattern with a set frequency. Was this just my imagination, or do millipedes actually move their legs in such a manner? If they are able to coordinate such an elegant way of moving, are they able to move any other way--one without such symmetry?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1fu0tc/how_do_millipedes_walk/
|
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"A quick google search (\"Millipede locomotion\") gave me [this hefty mathematical paper](_URL_1_) but otherwise as far as I remember each pair of legs moves one after another in a wave. [This video](_URL_0_) shows the action clearly and simply. So essentially yes, they move in waves.\n\nAs for if they're ~~about~~ able to de-synchronize or otherwise move them independently I do not know. Each pair of legs has to move together on the segment they're attached to.",
"In robotics, locomotion with many legs is a common topic. Your eyes likely didn't deceive you; moving legs in a wave like pattern is a regular gait.",
"This is for a caterpillar, but I presume that the mechanism of motion is similar if not the same for a millipede.\n\nIn *Essentials of Materials Science and Engineering*, the author compares dislocation motion in a material to the motion of a caterpillar. It states: \"A caterpillar will lift some of its legs at any given time and use that motion to move from one place to another rather than lifting all the legs at one time. Another way to visualize this is to think about how a fold or crease in a carpet would move if we were trying to remove it by pushing it across rather than by lifting the carpet.\"\n\n[Here](_URL_0_) is a snapshot of the not-all-that-informative accompanying graphic.\n\nGiven this description, one can definitely describe the locomotion in the form of a wave, as the motion propagates down the critter.",
"First question: it was not your imagination, that's about how it works indeed. They have a segmented body, and each segment has a pair of neural ganglia that contain a [Central Pattern Generator](_URL_5_), or CPG. This thing most probably is able to maintain the cycle of activity on its own, even if you isolate it from the body. Fish actually employ the same thing for swimming (they have a CPG for each segment of their body; that is - for each muscle that makes salmon in a store look stripy). Even humans have a [CPG for walking](_URL_2_), even though this one is not nearly as autonomous as in worms or fish.\n\nAnyway, so you have a bunch of CPG in a chain, and now you:\n\n1) Introduce connections between CPG on the left and on the right, controlling opposite legs. Usually it ensures a fixed phase delay between the legs, as it is important for maintaining a stable gait.\n\n2) connect CPGs to each other sequentially along the body, [making them interact](_URL_1_). Usually this kind of connection introduces a fixed lag between the phases of 2 CPGs nearby, which looks like a nice propagating wave in a centipede. \n\n3) You introduce long fibers that run along the whole length of the body, making connections on each CPG in each segment. Most animals have [at least 1 pair of fibers](_URL_3_) to [trigger escape responses](_URL_0_), and maybe a bunch of fibers to fine-tune the gait (to switch phase delays between the CPGs), and to [regulate speed](_URL_4_).\n\nNow, on your 2nd question. I don't know for sure (never studied centipedes), but I would expect them to have several speeds, and several gaits (at least forward / reverse motion). Most probably all these gaits will be pretty regular and \"symmetric\", because otherwise legs will move chaotically. These animals simply have too many legs to control each of them individually in a meaningful way, mathematically speaking. But maybe (probably) the levels of \"symmetry\" will be different: different phase lags between segments, and thus different \"wavelength\" along the body; different delay between left and right to make a turn, etc. (Edit: references)"
]
}
|
[] |
[] |
[
[
"https://www.youtube.com/watch?v=46a_AA5-Ick&wadsworth=1",
"http://files.thaiday.com/news/science/Walking_With_A_Millipede.pdf"
],
[],
[
"http://imgur.com/N4n5yOQ"
],
[
"http://www.sciencedirect.com/science/article/pii/S016622369801340X",
"http://biorob.epfl.ch/salamandra",
"http://en.wikipedia.org/wiki/Spinal_Locomotion",
"http://en.wikipedia.org/wiki/Mauthner_cell",
"http://www.sciencemag.org/site/feature/data/prizes/eppendorf/2009/mclean.xhtml",
"http://en.wikipedia.org/wiki/Central_pattern_generator"
]
] |
|
1dgnwp
|
How did this mountain ridge form? pic inside
|
_URL_0_
This is a picture of a mountain ridge near San Alberto, Mexico a seen from the ISS. How does a formation like this happen? What causes the range to split? or to appear to split?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1dgnwp/how_did_this_mountain_ridge_form_pic_inside/
|
{
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"c9q6tb9",
"c9qa60j"
],
"score": [
147,
13
],
"text": [
"What you have there is an anticline structure - Imagine a fold in the rocks running NE-SW. MAybe 5-10 degrees dip on either side, but with the NW corner dipping down toward the NW, and the SE Corner dipping SE. These kind of large scale folds are very common in geology. Once the fold is excavated to the surface differential weathering can start to occur.\n\nThe axial ridge has exposed the lower strata, which are harder. Hence they stick up, while the surrounding softer material is eroded down to form a flat plateau. In the very centre, where the fold is doming slightly, even deeper but softer strata have been exposed, giving you the plateau in the middle. An easier to see example can be find in the Zagros: _URL_1_\n\nWhich look like this from an angle _URL_2_\n\nEDIT - I just built a 3D model of it you can pan around: _URL_0_",
"I don't know why folks like OrbitalPete take the time to give such detailed answers, but I sure am glad for it. Is the incentive just to give solid answers to solid questions? If so, just know there are people who are grateful for seeing this kind of knowledge share on the internet/reddit. Hope I'm not beating a dead horse saying this."
]
}
|
[] |
[
"http://imgur.com/drZDIXj"
] |
[
[
"http://app.visiblegeology.com/model.html#ahFzfnZpc2libGUtZ2VvbG9neXINCxIFTW9kZWwYieo9DA",
"http://3.bp.blogspot.com/-x5O8ZlnFR0Y/UVoAm9Iu8SI/AAAAAAAABfY/s0fNNdQ1PVc/s1600/ZagrosAnticlines.jpg",
"http://flatrock.org.nz/static/frontpage/large_zagros_anticline_.jpg"
],
[]
] |
|
b7xi4m
|
why dont oasis in deserts get filled by nearby sand over time
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/b7xi4m/eli5_why_dont_oasis_in_deserts_get_filled_by/
|
{
"a_id": [
"ejuvd42"
],
"score": [
3
],
"text": [
"An Oasis gets its water from underground aquifers. So the water would just push any sand away. Also the presence of plant life around it helps keep the terrain stable, reducing the amount of stuff that'd disrupt things."
]
}
|
[] |
[] |
[
[]
] |
||
3le4xg
|
what dictates a wonder of the world?
|
I'm a bit confused as to why there are only 14, 7 from ancient and modern world, and why they chose those 7 for each specifically. For the longest time I thought stonehenge was a wonder, but it wasn't, as well as the easter island heads, those things were full of 'wonder' as people couldn't figure them out. But they aren't put as wonders.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3le4xg/eli5_what_dictates_a_wonder_of_the_world/
|
{
"a_id": [
"cv5kbit"
],
"score": [
6
],
"text": [
"There is no particular standard, only tradition. The Greeks made lists of amazing things from around the Mediterranean world familiar to them. Most of these lists made 7 choices because the number was (and often still is) considered lucky; counting the sun and moon, they knew of seven planets.\n\nAntipater of Sidon made a particularly popular list which many other authors referred to, and which has survived into the present day as *the* list of the Wonders of the Ancient World. His choices were arbitrary based on what he knew.\n\nRecently, people have tried to make lists of modern wonders based on various criteria. (The idea being that they are only possible with modern technology.) There's no particular list that is commonly accepted as authoritative."
]
}
|
[] |
[] |
[
[]
] |
|
73rsfz
|
inflation & deflation
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/73rsfz/eli5_inflation_deflation/
|
{
"a_id": [
"dnslo7y"
],
"score": [
2
],
"text": [
"Inflation & Deflation aren't about currency rate, they are about price level in a country. Despite the reason inflation makes some products more expensive, or you can buy lesser with money you have. You can't increase salaries at the same time because it will cause futher increasing of the prices (it is actually one of the reasons). The problem of inflation is in behavior of people and firms, when prices go up people can't afford to buy some things therefore firm can't get their profit and won't be able to pay loans or invest in futher production, then the amount of supply will decrease. When supply decreases usually prices increase so there is a cycle: goods are expensive, people buy less, lesser goods are produces, goods are more expensive. \nDeflation is bad as well. If you can buy a can of coke for a dollar today and two cans next year, you will be saving more money and again, companies won't be able to pay loans etc."
]
}
|
[] |
[] |
[
[]
] |
||
8dfsez
|
how do snails not lose all of their body mass as slime left on the floor while travelling?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8dfsez/eli5_how_do_snails_not_lose_all_of_their_body/
|
{
"a_id": [
"dxmqw86",
"dxms06p"
],
"score": [
3,
2
],
"text": [
"Imagine it like sweating. You can sweat and sweat, liquid comes out of you, but your body mass stays more or less the same.",
"They do lose some. But just like you can continue to make snot and saliva, pee and poop, they consume material to make more."
]
}
|
[] |
[] |
[
[],
[]
] |
||
5xbbj4
|
What were Aztec shield fringes made of?
|
A very niche question, I know, but I remember there being some Mesoamerican specialists here - hopefully some familiar with material culture. I would like to know what is known or theorised about the materials used for the fringe depicted as hanging from the bottom edge of Aztec shields, like [these examples from the Codex Mendoza](_URL_0_).
An excerpt of a fairly old academic book I read (which I now can’t find, sorry) refers to this as being made of feathers, and certainly they are often shown to have feathers hanging from the bottom edge of the fringe, but the drawing of the main body of the fringe seems inconsistent with how feathers are depicted elsewhere in the same drawings; either the distinctive long wavy green feathers of the resplendent quetzal or as a small oval with a line some of the way down its length to indicate the rachis.
In addition, the shape of the fringe, which is (I think?) quite consistent between sources, would not be possible to make with ordinary feathers, and would also be too large to make out of the feathers of any brightly-coloured native bird, except by feathering some supporting material. They’d also be very prone to damage, though obviously practicality seems to have taken a backseat to looking extremely intimidating in Aztec battle-dress.
However, I know how an untrained eye can very easily misinterpret drawings like these and take common artistic conventions far too literally.
Would it be reasonable to reconstruct the fringe as painted leather with a feather border, and if so, do you think it should have separate flaps or just lines painted on?
Thanks in advance for your help - I know it’s difficult to make any definitive statements about drawings with very little supporting surviving material.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5xbbj4/what_were_aztec_shield_fringes_made_of/
|
{
"a_id": [
"degu0tb"
],
"score": [
15
],
"text": [
"You are correct that fringes are made out of feathers. In section \"Defensive Weapons\" in Ross Hassig's book *Aztec Warfare* (1988: 85-88), he covers the topic of shields. While Hassig describes different construction material and methods for shields, he does not describe the fringe as anything but feathers. However, Hassig does not specify which feathers were used for the creation of a shield fringe, only that shield used feathers and the feathers offered protection by deflecting projectiles. If you look at the [feather shield](_URL_0_) located at the Museum fur Volkerkunde, Vienna, you can see that the feather fringe of this shield is not made with long feathers like the quetzal feather. Instead, it appears to have been made from shorter feathers. If feather shield construction is like other featherworking in Aztec culture, these feathers should have come from any number of birds and have been dyed before being attached to the shield.\n\nI hope this clears up any confusion.\n\n---\n\n* Hassig, Ross. Aztec warfare: Imperial expansion and political control. Vol. 188. University of Oklahoma Press, 1988."
]
}
|
[] |
[
"http://bodley30.bodley.ox.ac.uk:8081/MediaManager/srvr?mediafile=/Size4/ODLodl-1-NA/1020/bodl_Arch.Selden.A.1_roll113D_frame28.jpg&userid=1&username=insight&resolution=4&servertype=JVA&cid=1&iid=ODLodl&vcid=NA&usergroup=ARTstor&profileid=4"
] |
[
[
"http://www.mexicolore.co.uk/images-5/543_16_2.jpg"
]
] |
|
16l1s3
|
Did creatures such as terrestrial hermit crabs make it onto land before the ancestors of modern reptiles and mammals?
|
I don't really have anything else to add except thank you for your input in advance.
|
askscience
|
http://www.reddit.com/r/askscience/comments/16l1s3/did_creatures_such_as_terrestrial_hermit_crabs/
|
{
"a_id": [
"c7x4plt"
],
"score": [
3
],
"text": [
"There were terrestrial arthropods before there were terrestrial vertebrates. Terrestrial scorpions and millipedes predate early terrestrial bony fish. See the Wikipedia article on the [devonian](_URL_0_) for a brief discussion of these early terrestrial arthropods. "
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Devonian"
]
] |
|
1jew59
|
why was there a theory that nothing can go faster then light?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1jew59/why_was_there_a_theory_that_nothing_can_go_faster/
|
{
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"text": [
"Your wording is odd. You ask \"why was there\" is if it's not a current theory. As far as we know, it still holds true. As to why, see the other commenter.",
"The relativity theory is very much valid.\n\nI can try to explain a bit, but it's probably better explained by minute physics.\n\nFirst watch this: \n_URL_2_\n\nand then watch this: \n_URL_1_\n\nIt's a great youtube channel in general, so if you're not bored yet, go here: \n_URL_0_",
"The theory of relativity relies on defining the speed of light in order to make the math work. The speed of light in a vacuum, c, is also the speed of physics (cause and effect). It's like the network latency between different parts of space.\n\nThe assumption that the speed of light is constant and that nothing can go faster that it makes the theory of relativity work. And relativity leads to some non-intuitive conclusions that can be tested experimentally. And those tests have all come back positive. And the theory of relativity at its core is simple and elegant; so it is likely that it is true.\n\nBy the way, if you're asking this question because you're thinking about faster-than-light travel, there are ways around that. Just think about how to travel without exceeding the speed of light through the space that you occupy. The Alcubierre Drive gets around this by stretching space ahead and behind you, so you're never breaking the speed of light even though you kind of are. Wormholes are another idea, where you travel along a shortcut that connects distant parts of space, but along that path you don't exceed the speed of light.",
"The idea is not that something's holding back particles from going beyond the speed of light, but rather, the idea is that its **logically impossible** for anything to go faster than light.\n\nThe speed-of-light is a fundamental constant of our universe. A large number of laws of physics are based on this constant. You can say its an \"innate property\" of our universe.\n\nSometime back, neutrinos were observed to go faster than light, and this was a shockwave to every physicist, because if it were true, then all our fundamental laws of physics would have to be re-worked. It was later found that this was due to an experimental error, and the neutrinos never traveled faster than light. This means our laws of physics were correct all along and all is well."
]
}
|
[] |
[] |
[
[],
[
"https://www.youtube.com/user/minutephysics/videos",
"https://www.youtube.com/watch?v=lR4tJr7sMPM",
"https://www.youtube.com/watch?v=NnMIhxWRGNw"
],
[],
[]
] |
||
90dv3t
|
why aren't news stations (local, national, international) required to cite sources?
|
All (or most, I skimmed) of these responses seem reasonable and logical. I know it would be difficult if not impossible to do so without imposing on freedom of speech, but it just seems there must be some way to be able to verify information and a simple, truthful, immutable way which cannot be manipulated or corrupted. I feel there is a technology waiting to be discovered.. maybe it's just hopeless optimism. But then again, innovations have been doing what was once thought impossible time and again, and since history is bound to repeat itself.. well. One can hope, for the sanity of humanity (rhyme intended)
Thanks for all the input!
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/90dv3t/eli5_why_arent_news_stations_local_national/
|
{
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"text": [
"One reason that news reporters (be they text or video) are not required to cite sources is that doing so can result in the firing, the arrest, or even the execution of the people who are their sources. Journalists take protecting these sources very seriously. ",
"Because asking for sources and punishing s newspaper if they are absent is a pathway for censorship. Who defines if it's enough of a source? The government?",
"Who do you think has the power to make them do so?\n\n > Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.\n\nSo, in the US, at least, they can't (and shouldn't) be forced to.\n\nYou want to be careful that the medicine isn't worse than the disease. A free press is kind of a big deal in a free society.",
"You can't 'require' anything from the press, in the US. Freedom of the press means what it says on the tin.\n\nHalf the time, they're the ones doing primary journalism anyway when reporting on their relevant spheres, so they're their own source.",
"Aside from all of the wonderful explanations so far, I'd like to point out that if you contact a news station and ask for the specific sources that lead to a broadcast, they'll often email them to you at no cost. ",
"They often do, for example when they interview someone and use that information they say so, \"During our interview the president said...\" Other times, when they use other news outlets they say which outlet they got the info from, \"The Associated Press reports that...\" When official statements come out they often refer to a press release or corporate/government report. The source citations can fly by unnoticed if you're not actively listening for them. ",
"If you are talking in the usa it goes with the freedom of the press. A true journalist would protect their source but make a great effort to see if the source is telling the truth.",
"The constitution.\n\nFreedom of speech. Freedom of press. You can report any story you want and choose to divulge or not divulge sources. Because the government cannot dictate the content. Of course if your story isn't accurate and causes damage to someone you may be subject to civil action against you. Free speech is not without consequence.",
"Because the news station itself is the source. Their capture of the information through interview or video or both provides the informational content.\n\nThere are some cases where you will hear a newscaster say \"From our sister station at KXED in Des Moines.\" or \"NBC's National Correspondant Joe Blow\". That's their way of citing as well.\n\n"
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
|
gcg9k
|
What do sunglasses protect the eyes from?
|
With the days getting longer on the northern hemisphere I see more and more people with sunglasses again. I wonder if there is an actual medical aspect to wearing them, apart from avoiding the "too bright" feeling.
* UV radiation comes to mind first. Does it damage the retina, the lens or the liquid? At what point is the damage permanent?
* If non-tinted glasses which absorb UV light* are already worn, can the normal spectrum overwhelm the eyes as well?
* Can wearing sunglasses for too long make the eye overly sensitive?
\* Do all glass lenses fully absorb UV? What about plastics?
|
askscience
|
http://www.reddit.com/r/askscience/comments/gcg9k/what_do_sunglasses_protect_the_eyes_from/
|
{
"a_id": [
"c1mjp7t"
],
"score": [
4
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"text": [
" > UV radiation comes to mind first.\n\n[WHO - Effect of UV on Eyes](_URL_0_)\n\nTL;DR: UV is bad for your eyes. \n\n > * Do all glass lenses fully absorb UV? What about plastics?\n\nNo and no.\n\n[Sunglasses/protection (wikipedia)](_URL_1_)\n\nNever wear sunglasses that *don't* offer good UV protection. Dark lenses reduce the light entering the eye so the pupil dilates to allow more light in. Problem is that also lets more UV in. So shades without UV protection do *more* damage to your eyes than no shades at all."
]
}
|
[] |
[] |
[
[
"http://www.who.int/uv/faq/uvhealtfac/en/index3.html",
"http://en.wikipedia.org/wiki/Sunglasses#Protection"
]
] |
|
3wz3ja
|
how are sentences by judges that are aimed at making an example out guilty parties not a violation of "equal justice under law", and therefore unconstitutional?
|
Edit: out of*
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3wz3ja/eli5_how_are_sentences_by_judges_that_are_aimed/
|
{
"a_id": [
"cy01moi"
],
"score": [
3
],
"text": [
"Each type of crime has a valid minimum and maximum sentence. As long as the judge stays within these guidelines, it is 100% legal."
]
}
|
[] |
[] |
[
[]
] |
|
3nh72n
|
why don't tv shows/movies show real websites like google and facebook? why use fake websites that look like them?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3nh72n/eli5_why_dont_tv_showsmovies_show_real_websites/
|
{
"a_id": [
"cvo0n6h"
],
"score": [
2
],
"text": [
"Because you gotta call them, ask for permission, sometimes they ask for a certain fee, have their PR people see if their product is being used in good faith, all that paperwork and time just isn't worth the trouble. You can literally have a mock up site with basic functions working in one or two days and pay the guy 200 bucks for it.\n\n"
]
}
|
[] |
[] |
[
[]
] |
||
5lcm18
|
why do old games running on new hardware still have technical issues?
|
I am playing some mega man games on my Xbox One and experience slowdown when there are a lot of enemies on screen. but the Xbox One is significantly more powerful than the NES, so why is there still slowdown on this hardware?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5lcm18/eli5_why_do_old_games_running_on_new_hardware/
|
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"text": [
"The XBox is emulating NES hardware and running the emulation at a set speed. If it ran it at as fast as possible, then it would be several times faster than the original NES game and would be unplayable. I can't speak for Mega Man exactly, but older games tended to run on a cycle locked to the screen refresh which was a fixed 60Hz or 50Hz. There was only one piece of hardware they ran on, so there was no need to adjust for different hardware speeds.",
"In that case, it's probably on purpose - they want to emulate the experience as closely as possible, even including the slowdown and sprite flickering. Some emulators let you turn it off, but it's usually turned on by default.\n\nIn other cases, like if you're trying to emulate PS2 games on your PC, the game might just run really slow in general. Even though your PC is way more powerful than a PS2, it has to \"translate\" from PS2 language to PC language in realtime, which is much more difficult than running PS2 code on the PS2 itself.",
"The emulator is designed to match the actual behavior of NES hardware under real conditions as closely as possible. It is actually very important that an emulator be designed to do this, otherwise it can cause problems. In rare cases, a game will be designed to work around or even make use of a specific hardware fault or issue, and will crash or fail to work entirely when the emulator doesn't replicate this. \n\nA good example of this is Speedy Gonzales on the SNES. Only Higan , which has cycle-accurate emulation, will successfully run the entire game. All other emulators will freeze at a very specific point. Another would be the YM2612 FM synthesis chip from the Genesis/Mega Drive. All current Genesis emulators only emulate the very similar but not identical YM3438, and earlier games that used the unique distortion present in the YM2612 will not have proper music emulation.",
"This sounds similar to a situation I experienced years ago with varying graphics computers in my art department. Back in 1990, my Mac computer was older than the newer more powerful Macs my staff had. Yet my computer which did not have the power of the others displayed faster than the newer computers because as we would discover my monitor port was faster. So even though the newer computers could process the math faster, they could not render it faster so the visual perception was slower. \n\nAs for having so many enemies on the screen, this sounds like a problem unrelated to the power difference. I still love to play Dune on my PlayStation II, and I love to reach the point where I have big battles with lots of tanks, men, quads, gun towers and buildings and the game will crawl. But I notice that the enemy action the computer generates isn't as slow to act as the commends sent by me via the controller. My men move slowly while the enemy moves faster. Thus there is a timing difference in processing between those commands sent via the controller port vs. those sent by the cpu. Both the cpu commands and the controller commands are sent equally to through the TV port. There is a time delay between what I see on the screen, my reaction and commands, processing those commands and sending the result to the monitor. The enemy does not have as long a time delay because there is no controller involved. When there is less action on the screen we probably don't notice the time difference, but when the action is heavy and the processing overwhelms the cpu external commands get second priority. "
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
1ws0oi
|
Does an eagle see things that are say, 2 feet away in microscopic detail, blurry (like looking through binoculars) or simply as we would see them?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1ws0oi/does_an_eagle_see_things_that_are_say_2_feet_away/
|
{
"a_id": [
"cf519vq"
],
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94
],
"text": [
"They can actually change the focal length of their eyes by deforming them with muscles. That said, the optics of a microscope and a telescope are very different. If they had their eyes in \"far away mode\", everything would be blurry, like looking at a bug through binoculars.\n\nIf they were in \"normal mode\", their vision would be... Well... Normal.\n\nI have no idea if they can deform their eye to zoom in on tiny things close up, though I can't imagine why they would be able to do this. It doesn't seem like what they evolved for."
]
}
|
[] |
[] |
[
[]
] |
||
esbsy7
|
when a court tries to discover whether someone is guilty or innocent, does their lawyer know the truth?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/esbsy7/eli5_when_a_court_tries_to_discover_whether/
|
{
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"text": [
"Sometimes they know sometimes they don't. \n\nAttorney client privledge is a common law understanding in the US that your lawyer cannot divulge or be forced to divulge what you've told them. \n\nThis way you are encouraged to tell them the truth so they may best come up with a plan for your defense. There are of course some accused who will not admit guilt to their attorneys. Realistically we would never know if attorney knew or not.",
"It's not guilty or innocent, it's guilty or non-guilty. You may think that it's not a small detail, but that's important. The court never know if the guy is innocent, they only know if there is enough good evidence to declare him guilty or not. The defender doesn't need to prove that he is innocent, only that he is not guilty.\n\nAs for the defender's lawyer, he could know or not know. It depend if the accused decided to tell his lawyer or not. The lawyer could also not know, but be pretty sure that his client did it. \n\nAnyway, at this point the lawyer only have 2 options. Either he decide to retract himself from the case, or he need to defend his client at the best of his capability.",
"All parties involved have access to all the evidence available. It's not like \"the truth\" suddenly manifests itself in the courtroom to the surprise of everyone present. Nor does it matter.\n\nThe defending lawyer isn't there to prove innocence. He's there to ensure that his client receives a fair trial, that the prosecution is doing their job, that the evidence brought forth is valid, and trying to cast reasonable doubt on every single statement brought to question in discovery. If that's impossible he still has the job of making sure that his client receives a fair treatment and sentencing even when guilty beyond doubt. \n\nHowever in most cases lying to your lawyer is a stupid move, because it hinders his ability to actually help you.",
"A lawyer is legally required to turn over all their evidence to their opponents before the court. The exception is his conversations with his client which are confidential. However statements in general is untrustworthy and there are plenty of cases where clients have admited their guilt to their attorney even though there are solid evidence they are innocent. So the lawyer generally does not know much more about the case then the rest of the court. However their job is not to hide the evidence but make sure their clients are getting the justice they deserve and are not getting punished too harshly. In a lot of cases there is no question of guilt but rather how hard the punishment should be. A lot of lawyers will even instruct their clients to not tell them more about the case then they already told police as that is unnecesary information to them. The lawyers job is to present the evidence to the court in a way which is most advantagious to their client. The question of guilt is not really part of the equation for them. That being said the lawyers have a lot of experience with liers and can often uncover their clients lies quite fast. So even if there is little evidence they can often make a pretty good guess about their clients guilt. But even criminals have the right to a proper representation in court and a fair punishment for their crimes.",
"In most cases the defendant's lawyer knows the truth.\n\nCourt is less about finding the truth, and more about proving something based on a given set of rules.\n\nWhich is why defense teams are not always as concerned about whether their client is innocent or guilty, it's based on the rules of evidence, can it be proven (beyond doubt).\n\nThere is no discovering of truth, the prosecution and defense share everything they have before hand.. it's aptly named discovery. So everything presented, both sides have had a chance to review (few exceptions apply) The only \"surprise\" is what a witness might say on the stand when cross examined. As in If one side calls a witness to the stand, the other side gets to ask questions. Normally the witness is prepared for the questions but maybe a curveball is thrown and the stress/question makes the witness answer in a way that was not predicted... Or a lawyer uses the emotions of the case (like anger, jealousy, etc) to get the witness to blurt something out.\n\nFinally, If there is a jury, then the judge is not there to decide if it's innocent or guilty, he is actually a referee designed to make sure both lawyers are following the rules. Since the jury (and most regular people) don't know all the rules of court and evidence. The judge will allow or not allow pieces of evidence, testimony, etc as a way to make sure all the rules are being followed.",
"They know what they've been told and been instructed to find out.\n\nBeyond that, it's as much hearsay as anyone else saying they \"know\" he did it.\n\nIt's also generally frowned upon to \\*admit guilt\\* to your lawyer and then expect them to plead your innocence. They will likely advise you not to say things like that, or to change your plea to guilty.\n\nThat would likely be via a roundabout \"I'm sorry, are you admitting guilt to me, thus putting me into a position where I couldn't ever represent to the court that you're innocent?\" kind of way that most people would take the hint and say \"Oh, no, I mis-spoke, I didn't do it, honest\" even though everyone involved knows exactly what's going on.\n\nA lawyer can't knowingly lie to the court. But given that attorney-client privileges means all such discussions are private even from the courts themselves, there's no (easy) way to prove that they are doing so. If, however, you said you were guilty and stabbed him with a knife you buried < here > and your lawyer then tries to act as if he weren't aware of that evidence when it comes up later, there is a massive legal problem. He can't just ignore that fact, necessarily.\n\nTip: Don't put your lawyer in that position. If you want them to prove your innocence, don't tell them you're guilty (and vice-versa!). They won't appreciate it.\n\nIf they think you're guilty, they're supposed to still represent your interests (e.g. a lenient sentence) but to do that they'll expect you to plead guilty.\n\nWhat they'll do is claim ignorance, even though they are more than smart enough to know what's going on, and advise you to plead guilty if you say you are. Anyone with half a brain will follow what they advise, which will basically be to never suggest you're actually guilty to anyone, including themselves."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
|
8yiwo3
|
is a fat muffin top at your belly caused because humans wear clothes around their waistline?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8yiwo3/eli5_is_a_fat_muffin_top_at_your_belly_caused/
|
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"Really good question! I am by no means an expert but it is my understanding that every person stores fat on their bod differently, however fat naturally collects around the waistline, modern clothes or not. Wearing tight jeans or yoga pants accentuates the “over hang” or “muffin top” on some people.",
"Yes, but not by much. Your fat stores are all located in/around your hips/pelvic region, they swell and become distended due to an increase in volume of fat storage. Squeezing into tighter clothing does cause certain shapes (i.e. muffin top) to form, but it has no impact on the overall volume. \n\nSo if you are carrying weight in your belly it's not like that weight is going to suddenly shift to your thights, it'll still be there but just in a different shape. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
h4ws4
|
Why aren't archaea human pathogens?
|
I'm an undergraduate microbiology student, but I am still pretty mystified by archaea. I realize archaea weren't discovered until relatively recently, but why aren't they more important from a human perspective? Do you think they will eventually be seen as important as bacteria?
What's the freakin' deal with archaea?!
|
askscience
|
http://www.reddit.com/r/askscience/comments/h4ws4/why_arent_archaea_human_pathogens/
|
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"That is an EXCELLENT question, and unfortunately there is not a very good answer yet. It's not fully known, but there are some ideas.\n\nIt has been proposed that because Archaea use different cofactors in their metabolism, eukaryotes don't provide a good \"food source.\" But this isn't completely satisfactory, as they do use some factors. To make this even less likely, some Archaea do act as commensals in humans, and \"host as a food source\" is not the only advantage to pathogenesis. So that's kind of out. It may be *a* factor, but it's not *the* factor.\n\nOne recent idea has to do with the genetics of pathogenogenesis (not a typo...refers to how pathogens are generated). One of the big ways a nonpathogen becomes a pathogen is via horizontal gene transfer of pathogenic genetic material. A friendly bug picks up a T3S or a Type II pilus gene (biochemical systems used by pathogens to injure host cells). That gene infers some kind of advantage to the friendly bug, and it starts to use it...BANG, pathogen.\n\nA big source of these is mobile genetic elements, like phages. This is Dawkin's selfish gene; eukaryotic viruses (like the common cold) infect eukaryotic cells and thereby increase their number. Prokaryotic pathogenogenic phages *transduce* bacteria, which are in turn induced to invade and colonize eukaryotic hosts and thereby increase the range of the phage genes. From the gene (phage) perspective, this not only gives benefit via direct replication, but also through more opportunities for further transduction. The commensals in the eukaryote are fertile ground, with unsullied genomes.\n\nAnd therein lies the reason (maybe): It is known that bacterial phages, on the whole, don't infect Archaea and Archaean phages don't infect Bacteria. This largely has to do with specific molecular differences between the two Domains. The result is that there isn't a good way to get those genes to jump from pathogenic bacteria into Archaea. The Arachaens don't have access to the pathogenogenic genetic information accumulated by Bacteria. Or, more accurately, the genetic information in the bacteria doesn't have access to the Archaean genomes.\n\nOK, so why haven't the Archaens developed their own pathogenic mechanisms? Where's the Archaean version of T3S? That's even less known. Maybe it's because Archaens did a lot of early evolutionary development in the absence of eukaryotes, more so than Bacteria. Whatever paths they took are somehow inhibitory or exclusive to pathogenic development. Due to early evolutionary commitments, they are forever excluded from independently developing the pathogenic lifestyle. \n\nMaybe it's just because the development of this complex system of mobile gene elements takes a lot of evolutionary steps, and Archaea just never have done the correct combination. (Implying that they could, but they've been around eukaryotes just as long as bacteria have. If they can, have had enough time to, yet haven't, why haven't they?)\n\nMaybe it's because there aren't as many Archaean commensals as there are Bacterial, and any putative Archaean pathogenogenic phage that gets in has a hard time finding the Archaean needle in the Bacterial haystack to carry it's genes.\n\nOr, maybe it's a combination of those things (this is where I'd put my money).\n\nEXCELLENT question, though.\n\n(edited for some typos...got a little excited while typing and accidently a fw lttrs words)",
"In addition to what klenow said, many archaea live in extreme environments - high temperatures, below-freezing temperatures, extremely acidic or basic temperatures, etc. They can't survive in our body - so they can't really be pathogenic. Hyperthermophiles would literally freeze to death at our body temperature. Their enzymes and proteins just don't function in the human environment. \n\nAnd, some Archaeans are considered to be pretty important. Some enzymes from thermophilic archaeans are used in laundry detergents, and some methanogens are used in bioremediation.",
"[Archaea linked to human periodontal disease](_URL_0_)",
"This is sort of an off the top of my head reason/question. But evolutionarily speaking, and due to them being incredibly old organisms, is it not possible that their pathogenic capability was rendered mute after a few million years of organisms evolving to cope with them. The \"include and transcend\" standpoint?",
"I found three interesting articles you might like:\n\n1. Gill EE, Brinkman FSL. The proportional lack of archaeal pathogens: Do viruses/phages hold the key? BioEssays. 2011;33(4):248-54.\n\n2. Cavicchioli R, Curmi PMG, Saunders N, Thomas T. Pathogenic archaea: do they exist? BioEssays. 2003;25(11):1119-28.\n\n3. Faguy DM. Lateral Gene Transfer between Archea and E coli is a contributor to the emergence of novel infectious disease. BMC Infectious Diseases. 2003;3(13):16-19.\n\nEdit: I've only skimmed these, they're on my list to read, ya know, after finals."
]
}
|
[] |
[] |
[
[],
[],
[
"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC395942/?tool=pmcentrez"
],
[],
[]
] |
|
1demj6
|
How long does a lobster live?
|
I read that they can live more than 100 years I find this hard to believe.
|
askscience
|
http://www.reddit.com/r/askscience/comments/1demj6/how_long_does_a_lobster_live/
|
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"they can, however their normal lifespan is around 15 years\n_URL_0_",
"It's hypothesized that they have the biological capacity to live somewhat indefinitely, barring bodily damage, predation, or disease. This is due to something called having a negligible rate of senescence, which is essentially aging. They're placed in the same league as tortoises, rockfish, Quahog clam, and bristlecone pine. The bristlecone pine has been known to live to ~5000 years. They expect this is the case due to growth calculations, aging methods, and because they are large bodied and still fertile at those ages. They can weigh up to 20kg and measure 1m in length from claws to tail.\n\nIn terms of the lobster, it does a very good job of DNA repair because of [telomorase](_URL_1_), by molting to get fresh structures, using stem cells to renew tissues, regenerate appendages, antioxidant usages, they're very good at detoxifying themselves of pollutants, and have pretty good immune systems.\n\nThey've been found at 76 years [New perspectives on the growth and longevity of the European lobster (Homarus gammarus)](_URL_3_)\n\nAnd the oldest known decapod was 176 years.\n\nThere has been no American lobster found to be 100 years old, but they are thought to be capable due to their very slow senescence.\n\nThe first paper, a review paper, is an excellent source if you're interested.\n\n* [Ageing and longevity in the Decapoda (Crustacea): A review](_URL_4_)\n* [History and prospects: symposium on organisms with slow aging]\n(_URL_2_)\n\n* [Emerging area of aging research: long-lived animals with \"negligible senescence](_URL_0_)"
]
}
|
[] |
[] |
[
[
"http://www.telegraph.co.uk/news/worldnews/northamerica/usa/4213315/George-the-140-year-old-lobster-to-be-released-by-New-York-restaurant.html"
],
[
"http://dx.doi.org/10.1196%2Fannals.1297.096",
"https://en.wikipedia.org/wiki/Telomerase",
"http://www.sciencedirect.com/science/article/pii/S053155650000228X",
"http://www.nrcresearchpress.com/doi/pdfplus/10.1139/f99-116",
"https://www.sciencedirect.com/science/article/pii/S0044523111000362?np=y"
]
] |
|
2faazm
|
our defense system in the united states if nuclear missiles were to be launched at us by another country
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2faazm/eli5_our_defense_system_in_the_united_states_if/
|
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"Honestly? Not super great.\n\nWe have some [missile intercept systems](_URL_0_) but mostly the US relies on its ability to say \"If you don't terminate your missile right now... we'll fucking destroy your entire country in one swing\".",
"Mutually Assured Destruction (MAD)\n\nThe US maintains a triad nuclear defense system meaning it can strike via land, air, and sea. You can not stop it from attacking if it has made the decision to launch. In the event of a nuclear attack on the US, or one of its NATO allies, the US will unleash it's nuclear armada on the aggressor, theoretically destroying them outright. \n\nThe US has experimented with missile interception systems but that have never had success rates that would offer any real defense against a major attack. ",
"Nice try Putin ;)"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/United_States_national_missile_defense"
],
[],
[]
] |
||
2ba4nl
|
Is there an upper limit of rotation for a pulsar? Also, is that upper limit uniform across all objects?
|
I just watched the videos posted in [this comment,](_URL_0_) and it got me thinking about something that hadn't crossed my mind before. Is there a limit to how fast something can spin, or does it just work on the same priciple as movement through space?
I figured I'd mention pulsars as they were the inspiration, but I'm interested in hearing if other objects have different limits.
|
askscience
|
http://www.reddit.com/r/askscience/comments/2ba4nl/is_there_an_upper_limit_of_rotation_for_a_pulsar/
|
{
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"text": [
" > Is there a limit to how fast something can spin, or does it just work on the same priciple as movement through space?\n\nIf you are talking about the relativistic limit, this is [Ehrenfest's paradox](_URL_0_).",
"Sure. At some point, the matter near the equator will start to rip apart, when the centrifugal forces become stronger than the gravity. You can see that pretty much everywhere on fluids or fluid like materials: When you rotate a pizza dough, it will flatten out. At some point, the outer parts will rip off. \n\nSame thing for planets and stars. Fast rotating objects like Jupiter or Wega have higher equator diameters than pole diameters, because the centrifugal force let the matter wander to the equator. You can even see this effect on earth's diameter. \n\nAnd this also counts for neutron stars too. However, since they are very small and dense, the effect is minuscule when rotating very slowly. Amazingly, a neutron star becomes smaller when being more massive. So a neutron star with higher mass couldn't just rotate faster because of the higher mass, but also because of the higher density before it rips apart. \n\nMassive neutron star have gravitational acceleration of about 100 000 km/s at their surface. So the equator regoin would have to be faster than about 1/3 the speed of light to rip apart. We haven't found any such neutron stars because... well the obviously wouldn't exist anymore. But we do have discovered some neutron stars being pretty close to it, as seen in the video. \n\nMeanwhile we have found faster pulsars then PSR B1937+21, which was mentioned in the video. The current record holder as far as i know is [PSR J1748-2446ad](_URL_0_).",
"There are several different limits to how fast an object can spin.\n\nThe first is practical: no rigid object can rotate so fast that its outer edge is traveling faster than the speed of sound of the material. The resulting centrifugal pressure would exceed the object's shear strength and tear it apart. This was actually an engineering problem during the development of Uranium enrichment centrifuges, and also fundamentally limits their size. [This](_URL_1_) has a brief synopsis of its history; originally aluminum was used for its ratio of strength to weight, but it was eventually replaced by maraging steel for its higher shear strength, allowing faster rotation.\n\nThat is a fundamental limit on the rotation of any rigid object, but stars are not really rigid! The second limitation, potentially relevant to exotic stars like pulsars, is the relativistic limit. Technically rotation falls under the purview of general relativity, but we can still look at it through the lens of special relativity. From SR, we know that nothing with mass can travel faster than the speed of light in a vacuum, and this applies to the edge of any rotating object as well. Once the instantaneous tangential velocity of the surface of the the star approaches the speed of light, relativistic effects will come into play, and no matter what the surface will never be able to reach the speed of light. The actual rotational limit is only a fraction of c for a neutron star, though; at a certain point, depending on the exact mass of the pulsar (which only tends to vary [between 1.4 - 3.2 solar masses](_URL_0_)), the centrifugal force would overcome gravity and the outer layers would be flung into space."
]
}
|
[] |
[
"http://www.reddit.com/r/videos/comments/2b8th3/ever_wonder_what_space_sounds_like_its_terrifying/cj317fb"
] |
[
[
"http://link.springer.com/article/10.1007%2FBF00708527#page-1"
],
[
"http://en.wikipedia.org/wiki/PSR_J1748-2446ad"
],
[
"http://en.wikipedia.org/wiki/Neutron_star",
"http://en.wikipedia.org/wiki/Zippe-type_centrifuge"
]
] |
|
3wewk9
|
why do storm troopers wear armor if it doesn't actually protect them from anything? it also apparently interferes with their ability to shoot accurately.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3wewk9/eli5_why_do_storm_troopers_wear_armor_if_it/
|
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"Psychological edge. A phalanx of faceless, white-clad, cold, armored soldiers advancing will make you shit yourself. It's a powerful image.",
"There are several theories as to their accuracy, they appear to be accurate all the time except for a few instances where vader lets his son and a small group of rebels escape on a few occasions to track them to various rebel bases. The armor, kind of like actual body armor, is no guarantee you wont get killed. Weapons are easier to make effective than armor because generally speaking its easier to wreck stuff that to build stuff. The armor is good against shrapnel, hits to extremeties, and might even keep you alive from an otherwise fatal shot, but a shot to the chest or head is always going to be potentially deadly even with the best armours money can buy (think boba fett) but these guys arent intergalactic bounty hunters, they are rank and file troopers, so they definitely are NOT getting the best stuff on the market, they are getting something that can be made as cheap as possible.",
"You should check out /r/asksciencefiction they'll give you a much more detailed answer.\n\nShort version is - much like body armor today, Storm Trooper armor is amazing at stopping non-military grade weapons. Someone in the full kit is basically immune to slug throwers (re: normal guns) unless they take a very unlucky hit to a joint/eye socket or if the round is specifically armor piercing or very large.\n\nBlasters are military grade tech and (naturally) can over match the armor. That being said, the armor has a great deal of ablative power and can often minimize the damage to the core body from a blaster. It'll hurt like hell and multiple hits are still likely to be lethal... but you have a better chance than you would unarmored."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
jdjul
|
Is the water ice present in the solar system the same as ice on earth, just much colder, or is it in a different phase?
|
I suppose I should specify I'm asking about the ice on the surface of icy bodies, or rather ice that isn't buried and under pressure. So, for example, is the ice on the surface of Europa or Enceladus the same as the water ice on Earth? What about cometary ice, is that the same?
I've read a few times about "ice as hard as rock" as well, if that is true is that because of the low temperature it's in (implying terrestrial ice is just as hard at those temperatures) or is it because the ice in those cases is in a different phase?
|
askscience
|
http://www.reddit.com/r/askscience/comments/jdjul/is_the_water_ice_present_in_the_solar_system_the/
|
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" > I've read a few times about \"ice as hard as rock\" \n\nJust to get you started:\n\n_URL_0_\n\nIce can have many different crystal structures depending on T / P. Not sure how mechanical properties change w/ crystal structure.",
"The short answer is that they aren't quite sure. Depending on the formation mechanism they have different predictions for which of the ice phases it might be in, not all of which are kinetically accessible. It turns out that theres a good chance that depending on how the water got there, rather than being crystalline it might be amorphous based on some spectroscopy they've done.\n\nFrom what I've heard, their goal is to experimentally do some of the formation methods in the lab and compare to spectroscopic data to see if they can do some mix and matching.",
" > I've read a few times about \"ice as hard as rock\" \n\nJust to get you started:\n\n_URL_0_\n\nIce can have many different crystal structures depending on T / P. Not sure how mechanical properties change w/ crystal structure.",
"The short answer is that they aren't quite sure. Depending on the formation mechanism they have different predictions for which of the ice phases it might be in, not all of which are kinetically accessible. It turns out that theres a good chance that depending on how the water got there, rather than being crystalline it might be amorphous based on some spectroscopy they've done.\n\nFrom what I've heard, their goal is to experimentally do some of the formation methods in the lab and compare to spectroscopic data to see if they can do some mix and matching."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Ice#Phases"
],
[],
[
"http://en.wikipedia.org/wiki/Ice#Phases"
],
[]
] |
|
21op7j
|
Why is the DNA replication process imperfect?
|
Until recently I've always taken for granted the fact that in explanations of the DNA replication process the mechanisms leading to mutations are imperfect. But now I'm curious as to why this is. Any explanation or direction on the matter is greatly appreciated.
|
askscience
|
http://www.reddit.com/r/askscience/comments/21op7j/why_is_the_dna_replication_process_imperfect/
|
{
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"text": [
"Because of the complexity of the protein engines at work. All told, there are a considerable number of steps necessary to correctly replicate DNA, and the process is different for the leading and lagging strands. However, I think on average there's only one error for every 10,000 replications. Most of these \"mutations\" are harmless. Some are bad and apoptosis signals cell death by suicide. Some are bad and don't initiate apoptosis and could possible lead to cancer. However, some are beneficial. And therein lies the rub.\n\nBut be glad, because without that error, evolution wouldn't occur.\n\nThis video gives you a sense of how complicated it all is.\n_URL_0_\n\n/biochemist"
]
}
|
[] |
[] |
[
[
"https://www.youtube.com/watch?v=4jtmOZaIvS0"
]
] |
|
abs03p
|
how did we find out that there are 365.25 days in a year?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/abs03p/eli5_how_did_we_find_out_that_there_are_36525/
|
{
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"Observation, and knowing when the sun should be where through relative position.\n\nWhen you chart the sun’s course every day of the year a pattern emerges (Note the position and degree of the light at the exact same time every day). That pattern is slightly off by a few degrees the following year, on a four your cyclical. This ellipsis is the foundation of time as we know it. ",
"With a [sundial](_URL_0_)\n\nA sundial tells you the time of day with the shadow of a stick: Noon is the point where the shadow casts the shortest shadow because it's highest in the sky at that time. It's also the easiest way to tell the cardinal directions without a compass, since the shadow is going to point exactly north at noon.\n\nNow if you start recording the distance between the stick and the shadow at noon each day of the year, you're going to figure out the dates of the summer solstice (where the sun is the highest in the year) and the winter solstice (where it is the lowest). The number of days between either of the solstices is the time it takes for the earth to revolve around the sun, and this will tell you that the year is 365 days long, a quarter day short of the more precise 365.25 days.\n\nHowever, after four years, the difference will add up to a full day, and the solstice will be recorded one day later than expected. This might have flown under the radar for a while since nailing the solstice to a day with nothing but a sundial is hard, but at some point they must have noticed that their calendar was wrong and corrected it. The Romans divided the difference between recorded and actual solstice by the number of years that passed, and got to 1/4 of a day per year.\n\nOther cultures came to different solutions to the problem, for example the Chinese lunar calendar occasionally jumps an entire month. I'm not quite sure how it works exactly though.\n\n\n"
]
}
|
[] |
[] |
[
[],
[
"https://en.wikipedia.org/wiki/Sundial"
]
] |
||
49howb
|
3 days underwater.
|
I saw an old post about a rather old story involving a Cook from a ship that survived 3 days underwater. the ship was "AHT Jascon 4," the man was named Harrison Odjegba Okene. Given the limited space, confined area, and amount of time how did he not run out of breathable air or die of C02 poisoning. " inert gas asphyxiation "
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/49howb/eli5_3_days_underwater/
|
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],
"text": [
"In short, they haven't come up with a good answer yet.\n\nThe key problem more than anything is hypothermia. He was trapped in freezing water, and found naked and alert. After three days in freezing water you'd expect someone to have drowned, let alone be naked and able to determine that someone was rescuing them.\n\nThe other problem is oxygen. While bubbles can trap oxygen under water, the oxygen will eventually dissipate into the water around it and be replaced with Nitrogen. Diving Bell spiders have been able to keep oxygen bubbles going for 37 at most. 72 hours has never been observed before, and this is from an insect that uses a tiny fraction of the oxygen of a human and wasn't experiencing hypothermia, which in respiratory terms is as intense as a heavy workout for how much oxygen you use.",
"The belief is that the air pocket was big enough and in combination with the pressurization of the air provided him enough oxygen, which was a very close thing he was almost out when found. The carbon dioxide was supposedly absorbed into the water at a rate that kept it from being deadly, he apparently splashed the water increasing its surface area and thereby increasing the absorption of carbon dioxide. He escaped hypothermia by making some type of platform which allowed him to not spend the entire 60 hours in the water. \n\n_URL_0_"
]
}
|
[] |
[] |
[
[],
[
"http://www.livescience.com/41688-how-to-survive-underwater-for-3-days.html"
]
] |
|
567vf3
|
Why are there bubbles in prince Rupert's drops?
|
physics -I am a glass artist and engineering student. I have recently been practicing prince Rupert's drops (and failing hard (I only have a one foot tall turkey fryer to quench drops (makes it hard to avoid sides and bottom with drop))). I could not help but to notice bubbles inside the drop when I knew 100% that there were none, especially of that size, in the glass before. So how on earth did they get there????? Did the Oxygen in the SiO2 get squeezed out of their bonds and manifest as a gas or something?? Because I'm pretty sure the drop doesn't open up to let any H2O in to be hydrogen or oxygen source for gas. If I could get a good response here it would seriously make my day!! I am just so curious and I have no clue what is going on. Thank you SO MUCH in advance for answering this if/when you do who ever awesome science guy or girl you are.
|
askscience
|
https://www.reddit.com/r/askscience/comments/567vf3/why_are_there_bubbles_in_prince_ruperts_drops/
|
{
"a_id": [
"d8h62lu"
],
"score": [
11
],
"text": [
"First off, you really don't need a turkey fryer oil quench make PRD. The whole point of the drops is that they are skin stress resistant, and should hold up to a fast quench. Most people make them in a tub of lukewarm water.\n\nThe bubbles are most likely trapped atmospheric gasses during the melting proceedure. This is commonly encountered when the frit is too coarse, leaving air bubbles between the particles. Finer grinding will reduce this, or leaving the melt to let the bubbles rise to the top (and adding viscosity lowering elements like Cao or other alkaline oxides) will help get rid of these. You may not originally notice the bubbles as they start off very small and then coalesce.\n\nA more specific composition or procedure can help narrow down where you are going wrong. \n\nThanks to Shelby (the classic text) and my super awesome glass engineer SO.\n\n"
]
}
|
[] |
[] |
[
[]
] |
|
1jln5o
|
why does fruit taste different after its dried?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1jln5o/eli5_why_does_fruit_taste_different_after_its/
|
{
"a_id": [
"cbfwijp"
],
"score": [
2
],
"text": [
"the flavor is concentrated since there is less water, it would be like making a cup of coffee with just a little bit of water so you had a thick mud... it would taste different."
]
}
|
[] |
[] |
[
[]
] |
||
d3ivv2
|
exactly how are manual eye exams conducted (without modern digital equipment) and how can a doctor measure your eyesight through looking at your eye?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/d3ivv2/eli5_exactly_how_are_manual_eye_exams_conducted/
|
{
"a_id": [
"f03354t",
"f033ktw"
],
"score": [
3,
10
],
"text": [
"What do you mean measure your eyesight? As in determine your visual acuity?",
"Before the fancy digital eye scanner... They had you look through lens and ask if it was better or worse...."
]
}
|
[] |
[] |
[
[],
[]
] |
||
3b9rxy
|
Why was the USSR so interested in space flight? What started the USSR space program? Was NASA created only as an answer to Sputnik, or was it already in the works before hand?
|
What was the inspiration to shoot things and people into space? Was it just the next logical step from missiles? Was it purely a militarized application or inspiration at first?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/3b9rxy/why_was_the_ussr_so_interested_in_space_flight/
|
{
"a_id": [
"cskbp0p"
],
"score": [
2
],
"text": [
"The sputnik programme was introduced by Koroliov (previously doing rocketry) due to fears his team would \"lose the priority\" if the USA launched an artificial sattelite first (as they were planning to do for the international geophysical year).\n\nsource: [S.P.Korolëv quoted on _URL_1_](_URL_0_)."
]
}
|
[] |
[] |
[
[
"http://www.cosmoport.com/spacecraft/spacecraft-9.html",
"cosmoport.com"
]
] |
|
3x0k6h
|
when and why did we switch from saying liberal/conservative to progressive/regressive in us politics?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3x0k6h/eli5_when_and_why_did_we_switch_from_saying/
|
{
"a_id": [
"cy0ftbi",
"cy0fw54",
"cy0gdaz"
],
"score": [
3,
3,
4
],
"text": [
"Political terms change over time, and often have many different meanings.\n\nHistorically, a \"liberal\" was someone who believed strongly in republicanism and democracy. The \"conservatives\" in England opposed the revolutionary change seen in France, seeing it as dangerous, and wanted to preserve the existing social order with moderate reforms.\n\n\"Progressives\" came later in the 19th century, and wanted wealth re-distribution and more social spending. It's really a better term for most Democrats than \"liberal,\" since the use of that term is not that applicable in American politics. On the other hand, \"conservative\" does match most Republicans.",
"Progressive is a nonsense word when it comes to politics. Is it progressive to support gay marriage? To expand government for social welfare programs? To prematurely strike disagreeable nations? Subjectively anything may be, but it may be regressive to others. ",
"A lot of politics comes down to terminology. Communists were difficult to argue with because they came up with they own bourgeois/proletariat jargon, giving them a home field advantage in any discussion.\n\nIn the 1980s, Republicans were successful in making liberal into a bad word, making Democrats shy away from it and becoming more moderate. Much of the sentiment remains, so liberal Democrats have reinvented them themselves as progressives.\n\nAs for the use of regressive, that is just childish name calling and word games. It is no different than pro-lifers calling their opponents pro-death. If you can't address your opponents with neutral terms or the terms they choose for themselves, you lack the maturity to carry on serious political discussion."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
1whqv4
|
Epigenetics, Methyl Groups, and Expression
|
Just kind of had my mind blown, and thought to ask askscience if I am getting it, or am confused, about the power that epigenetic (gestation/environmental/social) factors have in phenotypic expression.
The work described in the below video articulates the mechanism for this process, and got me to where I can envision the factors that basically super charge natural selection by affecting phenotypic expression through methyl group's actively changing expression based on environmental pressures.
So, my simple question is: Are we finally coming to a place where the
gene's expression, and the factors involved in influencing expression can elevate environment to a greater place in the modern nature/nurture debate? Is Lamarck playing an ace in his card game with Darwin from the grave?
Here is the video: _URL_0_
|
askscience
|
http://www.reddit.com/r/askscience/comments/1whqv4/epigenetics_methyl_groups_and_expression/
|
{
"a_id": [
"cf23wa0"
],
"score": [
6
],
"text": [
"I watched some of the video, but it was too long to finish, so please ask more questions if I've missed anything. \n\nI wouldn't say that a \"nature/nurture debate\" really exists anymore. It's now more like a \"nature-nurture interaction exploration\", because (as you've seen) both the fluctuating environment and the static properties of genetic units affect expression. Epigenetics, however, is not just the study of how the environment affects expression; it describes how *all* expression occurs.\n\nLet's do a quick overview of what epigenetics is and does. First of all, you have your traditional genetics encoded in the DNA. The As, Ts, Cs, and Gs form intricate patterns that can directly influence proteins (like transcription factors or RNA polymerases) or that can be transcribed into RNA and then sometimes translated into protein. Though the DNA is chock-full of this information, it alone cannot *use* that information to effect expression. This is where the myriad of proteins, enzymes, chemical groups like methyls, RNAs, and more come in: these extra players coat the DNA, interacting with precisely the correct DNA sequences in precise the correct ways. Certain proteins attach to the DNA and help wind and compact it so that RNA polymerases could never access the actual code (shutting off a gene), or other proteins attach and unwind the DNA, exposing a portion of the code to expression-inducing proteins (turning on a gene). The conglomeration of all these non-DNA bits *is* epigenetics. \n\nDoes the environment influence those non-DNA bits, causing differences in expression based on differences in environment? Absolutely. Does the DNA itself also interact with the non-DNA bits to cause differences in expression? You betcha. Can a person pass on some of their epigenetic code to their children? It is possible in some circumstances and for some genes, but not in as strong a way as Lamarck suggested. Was Mendel wrong? Not about how single diallelic genes are inherited, which (in my opinion) is all he was *really* gunning for. \n\nedit: Said Darwin, meant Mendel*..."
]
}
|
[] |
[
"https://www.youtube.com/watch?v=fYMmwa2oWyQ&feature=youtube_gdata_player"
] |
[
[]
] |
|
2fjpa2
|
sunk costs
|
Could it be explained with an example as well?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2fjpa2/eli5sunk_costs/
|
{
"a_id": [
"ck9uwtw",
"cka0t0p",
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],
"score": [
2,
2,
2
],
"text": [
"A sunk cost is a past cost that is not recoverable and specifically should not influence future decisions. For example if a company spends money on a consultant then that money would be sunk. Also money spent on employee training is a sunk cost. In contrast to money spent on a truck or a computer of which some money would be recoverable. ",
"Imagine that you are starting a business. Some of the costs you will experience may be:\n\nA) Pay a consultant to help you set up your business\n\nB) Rent a building to work out of\n\nC) Pay for electricity to run your machines\n\nD) Buy 1000 business cards\n\nJust about all costs can be put into 1 of 3 categories: (1) Fixed, (2) Variable, (3) Sunk. We categorize them to help us streamline processes, keep track of money and margins, and help make our companies stronger and financially healthy.\n\nA **Fixed** cost is just like it sounds. It is \"fixed\". The rent you pay on your building, for example, is likely the same amount each and every month. Let's say your rent is $1,000 per month. This means that I can correctly predict that after 1 year, it will cost me $12,000 (12 * $1,000) to rent my building. After 2 years, it should be about $24,000. A fixed cost will be nearly the same across a defined period of time with little to no change.\n\nA **Variable** cost, similarly, is what it sounds like, too. It varies. Your electricity bill, for example, will be higher when you use more electricity and lower when you use less. If, for example, your electricity bill is $1,000 one month to run your equipment, it may be $2,000 the next month if you double the amount of work/output. Likewise, if your electricity bill is pretty constantly $1,000, there is an **opportunity** to possibly reduce it by investing in more efficient machines which may then reduce the amount of electricity used (and then lower your bill). Overall, though, they fluctuate depending on the amount of work being done. This is *unlike* **fixed** costs, because your rent of $1,000 per month will be $1,000 regardless of how much work you do in your building. \n\nA **Sunk** cost is an expense that you no longer have control over. You have to just accept it. Let's say, for example, you pre-pay rent for a whole year and your contract prevents you from subleasing/renting it out to others. Suddenly, you find a better location and move. The $12,000 you paid in rent for your old building is a \"sunk cost\" because there is nothing you can do to recover it or a portion of it. Likewise, the 1000 business cards you ordered with the old address are a sunk cost, as there is nothing you can do to recover the money you spent on them. The consultant you already paid to help you is also a sunk cost.\n\nLet's say that you plan on reselling someone else's products through your company. You sign a contract with ACME Corp to provide you with 1,000 widgets at a cost of $1 per widget that you plan on selling for $2 per widget. It takes time for those 1,000 widgets to be made, but you form the agreement now.\n\nSuddenly, something happens in the market. No one really wants widgets anymore. In fact, the best you can do is sell them for $0.50 each when you end up getting them. So you've paid an expense of $1,000 expecting to make a profit of $1,000, but now you will make no more than $500 total, which means you paid $1,000 to lose $500. That $500 is a sunk cost. ",
"Just to add a simple example, let's say you paid $100 dollars for a concert ticket, Then, on the day of the concert, you decided that you no longer wanted to go, and you find that other people will only buy the same ticket from you for $60. Then the $40 dollars that you can't get back constitute the sunk cost.\n\nOoh, and here's a neat thought: almost all people find themselves subject to sunk cost fallacy, where they believe that making economically inefficient choices will somehow allow them to recoup sunk costs. For the above example, that would be the same as thinking to oneself, \"I don't want to go to the concert, but I have to or I lose those forty dollars,\" when the forty dollars have already been lost, and the real trade-off is between $60 and the opportunity to attend the concert."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
5kx7l3
|
why do some people silently mouth the words you're speaking along with you as you talk to them?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5kx7l3/eli5_why_do_some_people_silently_mouth_the_words/
|
{
"a_id": [
"dbr9bji",
"dbr9ye2",
"dbrh3ze"
],
"score": [
3,
2,
2
],
"text": [
"Probably improves understanding. At least you know they're paying attention to what you're saying.\n\nSome people have a hard time focusing, their minds wander.",
"Its a form of face mirroring. As social creatures people will mirror face expressions, to \"fit in\" with the social group. This is why people often will have the same face expressions as someone they are listening to them. Mouthing words is just another form of this.",
"I've actually caught myself doing this to waiters/waitresses. I have a hard time hearing sometimes when they go over the specials for the day and I tend to mirror what they are saying as I read their lips. I've found that it helps me better understand what they are saying. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
1pxoww
|
What is the latest known instance of serfdom in Western Europe?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1pxoww/what_is_the_latest_known_instance_of_serfdom_in/
|
{
"a_id": [
"cd74s41"
],
"score": [
2
],
"text": [
"Define Western Europe."
]
}
|
[] |
[] |
[
[]
] |
||
8u7qc3
|
why does everything computerised need regular software updates now opposed to older models? e.g. my xbox one needs to update monthly(ish) while my xbox original never did (or could).
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8u7qc3/eli5_why_does_everything_computerised_need/
|
{
"a_id": [
"e1d8qnm",
"e1d93p3",
"e1d98qv"
],
"score": [
9,
5,
2
],
"text": [
"Security is taken more seriously than it used to, particularly on consoles that are now much more online than they used to be (online multiplayer was a much newer thing for consoles during the xbox classic generation of consoles), and that are much closer to the computers we use every day. It was unlikely that your xbox would be an infection vector for viruses onto your home network, since it was a pretty shitty computer to run anything but games on; but your xbox one is more than capable, and it's probably connected to your network constantly as well.\n\nThreats are also constantly evolving; as more of the world becomes more computerized, there's more money to be made in cybercrime, and so organized crime and even some street-level gangs are making a move into digital theft and ransomware coding to get money. And no Microsoft or Sony or Nintendo-level company wants headlines about the latest ransomware that's exclusive to their console, so they keep a stream of updates that keep everything running.\n\nThe new and improved hardware also demands more complex software; more complex software means more bugs just by the very nature of coding, so bugfixes are near constant now.",
"Actually, the original Xbox DID have updates, but most people just received them via the disc, as opposed to downloading them. There weren't a whole lot of versions, though, and none provided major functionality changes. Mostly stability/anti piracy measures.\n\nIf you boot up your original Xbox and look at \"About this Xbox\" on the dashboard, it'll list the dashboard/system software version. Most recent is 1.00.5960.01.",
"The biggest reason is the rollout of 24x7 access to the internet. Before this was available internet access was limited to the times that you called in to your ISP modembank. These days your devices can access anything they want whenever they want, which means that the software providers are able to distribute updates whenever they want."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
18na44
|
What will happen when Pope Benedict when he dies, since he will not be Pope at the time?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/18na44/what_will_happen_when_pope_benedict_when_he_dies/
|
{
"a_id": [
"c8g9rg8"
],
"score": [
3
],
"text": [
"The way you've phrased the question, it's about current events/the future, which isn't appropriate for this subreddit. I'll have to delete this one, but you could resubmit with something like \"What happened to Popes who didn't die in office?\""
]
}
|
[] |
[] |
[
[]
] |
||
34gcky
|
how can bernie sanders an independent be the democrats presidential nominee?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/34gcky/eli5_how_can_bernie_sanders_an_independent_be_the/
|
{
"a_id": [
"cqueor6"
],
"score": [
3
],
"text": [
"He's not. He's seeking to be democratic presidential nominee. ELyou're5: he's hoping democrats will let him be leader of their club. "
]
}
|
[] |
[] |
[
[]
] |
||
4x2gir
|
how do screenshots work from a software perspective?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4x2gir/eli5_how_do_screenshots_work_from_a_software/
|
{
"a_id": [
"d6bv1hx",
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],
"score": [
13,
5,
2
],
"text": [
"The software just saves the state of all the pixels that the hardware is sending to the display and puts it into a standard image format that other programs can then open. How the software actually gets the pixel data is platform dependent.",
"The graphics card has the current frame saved in memory as part of the standard process. It's called double buffering - one finished frame on display, one being drawn. So, when you take a screenshot the CPU just asks the GPU for the current frame and then places the data in the clipboard. \n\nWorth noting that requesting data from the GPU is much, much slower than sending data to it. For the most part there is very little need to get data back. ",
"First we need to accept the fact that computers don't really show us streams of moving objects. They show frame by frame, each stored in memory of the video card.\n\nWhen you play a game or watch a movie, the central processor of the computer is sending data and commands to the graphics processor inside your video card. The data might be a video stream, pictures or textures. Commands might be to tell to draw the video stream in a certain area or full screen; they can also be to construct 3D objects and use some pictures as textures, to put some lights in a distance, all kinds of transformations with those objects, commands to add fog and reflections, and so on. The video card will render that data into still frames, and send those frames one by one to the monitor. One of the commands the central processor can send to the video card is to send the latest rendered frame back. That will be the screenshot available in the computer memory. The rest depends on what software you used to take the screenshot. Built in functionality of video games usually saves the screenshot into a file on the local disk. Windows will put that screenshot into the clipboard and you can paste it into another program."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
1mzw5s
|
Why do boats often leave paths of calm water (wakes) behind them?
|
I've wondered about this for a long time, but I was out on a pontoon this weekend and thought to ask here. (The answers google provides aren't very enlightening) A boat passed in front of us and left a trail of calm water hundreds of yards long, despite there being a strong breeze (~10-15 mph). The wind rippled the water everywhere but path directly behind the boat, and that water remained still for more than a minute. How, precisely, does turbulence suppress the effects of a breeze on the surface?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1mzw5s/why_do_boats_often_leave_paths_of_calm_water/
|
{
"a_id": [
"ccewduj"
],
"score": [
2
],
"text": [
"Waves on water surface are dependent on both wind speed and the amount of exposure the water has had to the wind (IIRC this is called 'fetch'). Essentially, even a fairly strong wind needs a pretty good amount of distance acting on the water to kick up waves on the surface. This is one reason why waves are bigger in the ocean and in big lakes vs. in ponds or smaller bodies of water. When a ship or boat passes by, directly behind it is a highly turbulent zone, which you correctly identified as a turbulent regime. Turbulent flows are full of chaotic motion like eddies and vortices, but somewhat contradictorily are really stable, i.e. it takes a lot of energy to change the water's tendency to stay in those wonky vortices. They also are peculiar in that they turn the surface very flat.\n\nLet's look at what we have. We have a boat going through the water that kicks it around into a really stable pattern that takes a lot of energy to change direction or motion, and leaves the surface flat. The wind is the only other external force that can remove that turbulence and impart those choppy waves on the surface again. But as we said, it takes a good amount of distance for the wind to act to gain enough strength to get the waves back.\n\nTL;DR boat swirls up the water, and wind needs time to get it back to wavy"
]
}
|
[] |
[] |
[
[]
] |
|
3zze1u
|
How come when you and a friend get out of a loud venue such as a concert and you can't hear as well your friend and you yell at each other when talking, instead of talking in your normal voice. ?
|
askscience
|
https://www.reddit.com/r/askscience/comments/3zze1u/how_come_when_you_and_a_friend_get_out_of_a_loud/
|
{
"a_id": [
"cyqc909",
"cyqr0bs"
],
"score": [
12,
3
],
"text": [
"Your ears have a mechanism to [temporarily lower their sensitivity](_URL_0_) in response to loud sounds. In that paper, they showed that if you knock out the gene responsible for this in mice, they exhibit less temporary hearing loss but more long term hearing loss. So it seems to be a mechanism to protect your hearing in the long term.",
"It's because we are constantly self-monitoring when we speak, i.e. listening to our own speech and using that as feedback to correct any perceived errors. [Here's a review article](_URL_0_) from a while back if you can get access. When you leave the concert, your hearing is temporally desensitized, meaning everything sounds softer and/or muffled, including your own voice. Therefore, you automatically attempt to compensate by speaking louder.\n\nThis is also the reason \"speech jammers\" work. Just search your phone's app store to find one. These are apps that add a small delay to an audio feedback, which is enough to trip you up and cause stuttering. \n\nLastly, this is unrelated, but wearing hearing protection at very loud concerts is always a good idea. There's a [growing body of evidence](_URL_1_) that the \"temporary\" hearing loss you get from loud concerts isn't so temporary.\n"
]
}
|
[] |
[] |
[
[
"http://www.pnas.org/content/110/18/7494.full"
],
[
"http://www.sciencedirect.com/science/article/pii/0010027783900264",
"http://www.sciencedaily.com/releases/2014/05/140507142804.htm"
]
] |
||
3d2en0
|
Do we know anything about a planet past Pluto?
|
I was reading _Quasar, Quasar, Burning Bright_ by Isaac Asimov, and he talked about the discovery of Neptune based on its effects on Uranus' orbit. Then he said "Neptune's pull only took care of about 59/60 of the discrepancy that had existed on the orbital calculations of Uranus" and related the history of the discovery of Pluto. After all that, he ended the chapter saying that Pluto's mass was far too small to account for the remaining 1/60 of the discrepancy and said
> But that means the trans-Neptunian planet (or trans-Plutonian plant, as it must now be called) that accounts for the orbital discrepancies must still exist and be out there somewhere. It is probably more distant than Pluto and must certainly be far more massive. Perhaps the size is great enough to make up for the greater distance so that it may not be much, if any, dinner than Pluto and can be detected with no greater trouble—but I have a feeling no one is looking.
What happened to that discrepancy? Has it disappeared with more data? If not, we have 80 years more information about Uranus' and Neptune's orbits than Lowell did, and we have orbital telescopes like the Hubble, which didn't exist even when Asimov was writing. Has anyone redone the calculations to try to locate a new planet?
|
askscience
|
http://www.reddit.com/r/askscience/comments/3d2en0/do_we_know_anything_about_a_planet_past_pluto/
|
{
"a_id": [
"ct1fpjt"
],
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],
"text": [
"Better calculations have removed the disparity. But that's a boring answer. There certainly are more dwarf planets past Pluto in the Kuiper belt. Makemake is of significant size, about 2/3 as big as Pluto. Eris, even farther out, is roughly the same size as Pluto. Here's a great diagram of their crazy orbits. \n\n_URL_1_\n\nAre there any more large planets out there? The WISE telescope rules that out. There are no planets on the scale of Neptune in the Kuiper belt. And there are no stars, not even brown dwarves, in the Oort cloud. To the best of my knowledge, we can't rule out Neptune sized objects in the Oort Cloud, but the odds are incredibly slim.\n\nHere's an article from NASA about the results of WISE's survey.\n\n_URL_0_"
]
}
|
[] |
[] |
[
[
"http://www.jpl.nasa.gov/news/news.php?release=2014-075",
"http://www.lionarray.com/uploads/2/0/8/3/20833448/3399729_orig.png"
]
] |
|
20kh8e
|
How was Italy governed by the Roman Empire? Was it treated like a province with its own proconsul?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/20kh8e/how_was_italy_governed_by_the_roman_empire_was_it/
|
{
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"cg485qs",
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"text": [
"I'm working on this right now, so this won't be a complete answer because I haven't finished my research yet, but I can get things started (and maybe learn something from other contributors!).\n\nFirst thing to ask is what the hell is \"Italy\"? In early Greek sources Italy seems to mean the Greek-inhabited southern coast. Herodotus I think has 8 references to \"Italy\" and all of them refer to Greek colonies. Over time the term \"Italy\" expanded to encompass the peninsula up to the Arno-Rubicon line, and finally in 42 BC Augustus extended it to the Alps.\n\nThe second thing to ask is what time period are you curious about? Rome had an empire from the 3rd century BC down to the collapse whenever you want to place that, and there were different governing arrangements in different times.\n\nFor the period I'm most familiar with, the Late Republic, management of \"Italy\" was left for the most part to magistrates in the municipia (Bispham, *From Asculum to Actium*, is the text I'm using most for this, though looking at Sherwin-White's *Roman Citizenship* can never hurt anyone), but proconsuls could be appointed to Italy, as Caesar was.\n\nAugustus revised the administration of Italy by dividing it into 11 regions. This seems to be part of a program to suppress banditry in the countryside, and troops were stationed at various points for making travel safe (This is the interpretation of Laurence, *The Roads of Roman Italy*. The sources for this are late and ambiguous). Cassius Dio (54.8) says the roads were administered by former praetors and accompanied by lictors. We also hear of *iuridici* for specific regions in inscriptions; obviously these have some judicial function. A third kind of officer were *curatores* who seem to be involved in specifically dealing with bandits (again, this is from Laurence - he's not clear on his sources here).\n\nI'm not too familiar with the later empire, but my understanding is Italy does lose its special status and I bet this had to do with the Emperor's court becoming more important that Rome the city (forgive me, mods!).\n\nAs I said, I'm currently researching this, so please if anyone has corrections or additions, let me know!",
"Awesome question. I have no answer. But I do have an extension to your question.\n\nAs a commoner, what was it like to be governed by the Roman Empire? I'm curious about the Italic tribes, but mainly wondering about Greece. Since Romans adopted Greek culture so affectionately, does it stand to reason that Grecian life under Roman governance was comfortable? Mainly interested in the period after the Macedonian Wars when Greece/Achaea became a Roman province."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1jhmmf
|
why are black holes invisible.
|
Ok, I've read alot on black holes, how they work, form and how we are detecting them. I pretty much read all there is on them in the Internet. However, one thing is not giving me peace. If a black hole "swallows" light, shouldn't they be visible by exactly that fact? I am aware of the gravitational lensing and stuff, but still why are they invisible and do not appear as black silhouettes in the sky? Yes, the sky is indeed black, but it is faaar from black for example in the galactic center of the Milky way. Thanks
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1jhmmf/eli5_why_are_black_holes_invisible/
|
{
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" > If a black hole \"swallows\" light, shouldn't they be visible by exactly that fact?\n\nNo.\n\nThe reason you see objects is because light reflects off them and hits your eyes. If nothing reflects off an object (ie, if it were to perfectly absorb all incoming EM radiation, or have an escape velocity above the speed of light, like blackholes), you can't see it, because no photons are coming from it. All you \"see\" in its place is a black spot, which, as you've figured out, isn't all that different from the rest of the sky.",
"We can't see black holes for a number of reasons.\n\nThey each by definition have an event horizon around them, trapping all light inside from ever escaping and making them black in appearance. But as you pointed out, space isn't black.\n\nOne problem with seeing black holes is their distance. The nearest black hole is the centre of the Milky Way galaxy. Whilst it is a supermassive black hole (basically just a really, really big one) it is still many billions upon billions of miles away, and there are billions upon billions of stars between us and the black hole, which are obstructing our view of it. Even if we did have a clear line of sight to it and no light pollution, it is so far away it would be like trying to spot an individual grain of sand with your bare eyes from an airplane at cruising altitude. Even with the planet's best space telescopes they are very hard to see.\n\nAnother problem is gravitational lensing, which you mentioned. Becuase of this effect, all you would see when looking at the black hole is the image from directly behind the black hole. So instead of a pitch black spot on a close-to-black background, you would just see the star or galaxy that is behind the blackhole.\n\nSo visibly spotting a black hole is not very practical using technology available today. But how do we 'see' them?\n\nWhilst gravitational lensing means we can't spot a black hole directly, it does let us spot them indirectly. If a star of constant brightness suddenly appears to get brighter and stretch or change shape, before quickly returning back to its orignal form, we can conclude a massive object passed in front of it and caused gravitational lensing. Using various calculations we can work out just how massive that object was in each case, and if the mass is great enough we can assume it was a black hole that passed by.\n\nAnother method for detecting black holes is by looking at objects in space that seem to be orbiting around nothing. A star cannot be in orbit around empty space, there must be some form of gravitational source the star is orbiting around. Again, through certain calculations we can work out the mass of the gravitational source the star is orbiting around and see if it is heavy enough to class as a black hole."
]
}
|
[] |
[] |
[
[],
[]
] |
|
448pmy
|
In warfare through history, why isn't there a severity of causalities compared to the unit size deployed?
|
I know war is horrible and many people die, but my question is, often through history in warfare, you have both sides deploy extraordinary large forces, but there is very little contact between those two bodies and the causality size is pretty small compared to the overall size of each side, you also have many incidents of the much larger forces doing a full scale retreat when they've lost less than 5%. Is it just good strategy? Or is the "fight to the death" mentality not really true. I apologize for my lack of 'military terms'
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/448pmy/in_warfare_through_history_why_isnt_there_a/
|
{
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"czoj83g"
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"text": [
"This is a big question, so I can only really answer in generalities. Still, I'll do what I can.\n\n > Or is the \"fight to the death\" mentality not really true.\n\nArmies are big, expensive things, to say nothing of the human cost of combat. To fully commit to attacking or defending a place means that the outcome of that battle must be absolutely decisive - something that will win the war. Such instances are pretty rare. What one battle could an army win to conquer the Frankish Empire? Or subdue the thirteen rebelling American colonies? Without the ability to win a clear decision, it's often better to keep the army together and wait for a better opportunity. In instances where one side does commit to a position - Thermopylae, the Alamo, Verdun- casualties can be extreme.\n\nAlso, remember that, in Western history at least, a lot of the more famous conventional military campaigns have been pretty symmetrical; both sides have similar weapons and capabilities. In most melee battles, the winner will take almost as many casualties as the loser (barring something weird, like Cannae) until the losing side breaks, runs, and is cut down in pursuit. During the age of muzzleloaders, professional military units engaging in an open-field shootout would both send about three rounds per minute into the enemy formation, resulting in similar casualties no matter how many people were involved. \n\nFor a discussion on the difficulties of achieving a decisive battle, check out Russ Wiegley, *The Age of Battles*."
]
}
|
[] |
[] |
[
[]
] |
|
3mzzwp
|
what causes people to hallucinate when they get a very high fever, and is it the body trying to protect itself in some way?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3mzzwp/eli5_what_causes_people_to_hallucinate_when_they/
|
{
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"text": [
"when you have a high fever, enzymatic action all over your body begins to slow and in the brain, this causes an unbalanced level of certain neurotransmitters and other psychoactive compounds. when this occurs, hallucinations, stroke, and other odd feelings begin to surface",
"First time I ever hallucinated during a fever (that I can remember) was this past winter with a flu that lasted 13 days (I'm 35 and in great shape/health). \nGot it from my cousins kids....I swear all kids need to be quarantined during the months of October-April..... \nBut I digress...so the hallucination was crazy...I was babbling about something, but only one word would come out....and I would know this but I would keep babbling while knowing that to my wife I am making absolutely no sense, and I kept at it for a good while, just having a convo with myself.... \nI've tripped a lot before but this was completely different to any psychedelics i've tried. I knew I was in bad shape and needed to cool down and even wondered to myself how my wife could not be realizing that i'm burning up and need to be cooled down, but I never said anything to her or did anything about it myself and I was totally ok with that....come to think of it, the closest way to describe it would be a trip that is a mix of mushrooms and heroin/opium. \nOver all great experience, 10/10, would do again....but seriously, no, I do not want that to happen again...with a kid on the way i'm going to make sure I have buckets of ice on hand and a thermometer rammed up her rectum 24/7 in case this shit happens to her.",
"Is there any rhyme or reason to what I hallucinate? Because I thought I was a general in the Irish army. I dropped from 143 lbs to 134 that fever. Crazy time I had tossing and turning in bed commanding my troops.",
"When I was a child I had a fever. My hand felt just like two balloons. Now I got that feeling once again. I can't explain you would not understand. ",
"High temperatures, esp. over 101 F. and 39 C. cause the brain to malfunction. It's called encephalopathy, technically. This is what creates the hallucinations.\n\nWe get fevers to fight infectious diseases for one big reason. Living systems have enzymes and metabolic rates which are VERY sensitive to temps. Get cooled off too much the immune system stops working very well. The flu season often starts when average daily temps are below 50 deg. F. \n\nBut when body temps rise, the metabolic rates, esp. of the immune system can nearly double or more in speed of operation. This allows the body to mount a very much faster metabolic immune attack on diseases. thus doing in a few days what might take a week or longer.\n\nConsider that in fighting a new disease in the body, the body must create a series of antibodies to attack the newly recognized infectious agent, like a bacteria, or as below, a flu virus. It takes the body about 3 days to really get a good antibody series created which can detect, attach to, and direct killer cells to wipe out the infection over time. If it had to wait a week or longer to get that going, then the person could die. So it ups the metabolic speed by creating a fever which then shortcuts the normal rate substantially.\n\nalso there is a sort of a complex system computer in the immune system which can sort through something like 1 trillions potential antibodies to find the 1/ones which can attack the infection. No human computer can do that immense task of creating antibodies of that great number and simultaneously testing them for effectiveness. PLUS manufacturing the infection killers in high enough quantities to do the job. It's an amazing system, our immune system is, and we are lucky to have those. But then again, those who didn't, likely died quite some time ago....."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
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||
bd7ucf
|
after suffering an injury, why are we told to elevate that part of our body over our heart? doesn't blood help heal the injured area and bring cells that heal it?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bd7ucf/eli5_after_suffering_an_injury_why_are_we_told_to/
|
{
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"Depends on how much blood we are talking about. Elevating the injury basically uses gravity to help overcome the blood pressure of that area, decreasing blood loss. I recall the story of a woman who cut her big toe - not a really horrible cut, but enough to produce a good amount of bleeding. Fearing the staining on her kitchen floor, she proceeded to wipe up the blood. As she moved backwards, wiping up the blood from her toe, she continued to bleed, so she continued to wipe. Being bent over and constantly moving, she eventually bled to death cleaning up her own blood. Had she just applied pressure and elevated her foot, she would have been fine.",
"Once you start swelling your blood vessels are squeezed. Arteries have the pressure of the heart to keep them open and flowing. \n\nYour veins are collapsed, and blood flow is restricted, because they don't have high blood pressure. By raising the damaged part you raise the pressure in the veins, which have an easier time draining toward the heart. Your lymphatic system, which is working hard as part of the healing process, also needs help with draining. \n\nIn addition, if you are bleeding elevation does help reduce blood pressure at the wound, and makes compression easier."
]
}
|
[] |
[] |
[
[],
[]
] |
||
7x6x9s
|
Alexander the Great founded dozens of cities and towns over his life. How was a town just "founded?"
|
Who were the first inhabitants? What consideration went into founding it? Where they built on existing towns and cities or just made?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7x6x9s/alexander_the_great_founded_dozens_of_cities_and/
|
{
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"text": [
"Hi, not discouraging other contributors, but meanwhile, check these out\n\n* /u/ikahjalmr in [In ancient times I've heard that historical figures \"built cities\" like Alexander did at Bucephala in honor of his horse. How did a ruler in Greco times go about establishing a city? What did that at a minimum constitute?](_URL_1_)\n\n* /u/Daeres in [Who populated the cities founded by Alexander the Great?](_URL_2_)\n\n* /u/theskyisnotthelimit in [How were cities founded by traveling armies in antiquity?](_URL_0_)",
"With regard to the practicalities, there's little I could add to [this](_URL_1_) old post by u/Daeres (already linked in this thread by the stalwart u/searocksandtrees), which answers the questions in your body post. I'd just like to address something that isn't really covered in any of the answers already given. You asked specifically about Alexander the Great founding cities, and this is a question that gets asked a lot. Because of the later prominence of Alexandria in Egypt, we strongly associate the practice of founding cities with this particular king, and it can seem as though this was a unique feature of his larger-than-life ruling style. But, of course, he did not come up with the idea. So instead of talking about *how* a city was founded, I'd like to talk about *why* this was something that Alexander (and his successors) kept doing.\n\nThe Greeks in general had been founding political communities for centuries, typically by establishing their urban centre and then outlining the territory associated with it. This has traditionally been referred to as \"colonization\", though the term is not really accurate, as I've recently explained [here](_URL_0_). What we're really talking about is migration, and the foundation of new independent communities abroad.\n\nWhen they were created, these communities were badly in need of some basic elements that hold groups of humans together. Brand-new settlements could not rely on established traditions or a common past; with the intermingling of newcomers from various parts of the Greek world and native populations, all claims to shared ancestry and culture rang mostly hollow. Instead, new communities worked hard to establish the common laws, institutions and cults that would shape and unite them. \n\nOne of the standard elements of this process of community formation was the establishment of a heroic cult for the Founder. This founder figure (*oikistes* or *archegetes* in Greek) was typically the man in charge of the initial wave of settlers; sometimes he would end up the ancestor of a ruling dynasty in the new settlement (as Battos did in Kyrene), but other times his role was complete once the new community was up and running. Either way, upon his death the Founder was generally honoured with religious cult in a centrally located sanctuary. This served the dual purpose of reminding citizens of the great venture in which they shared and giving them a festival in which to partake as a community. Before Hellenistic kings started to claim divine descent while alive, heroic cults were more or less the only way for Greek humans to become the subject of religious worship. \n\nThis is where founder cults start to get interesting for ambitious rulers. Cities were not bound to worship their original Founder forever; a decision of the government or assembly could overturn the custom and assign the heroic cult to anyone they chose. When the Spartan general Brasidas died in battle to help the Athenian colony at Amphipolis throw off the yoke of the Athenian Empire in 422/1 BC, the city voted to cast out the cult of the Athenian founder Hagnon, and to worship Brasidas as founder instead. This was the ultimate honour that a state could bestow on an individual; the hero was effectively declared to be like a god, and the city's true history was said to begin with him. There was no more prestigious way to be remembered.\n\nIt should come as no surprise that Greek commanders who had achieved important things for other states began to regard the practice of assigning founder cult to new heroes as a practice to be encouraged - even while they were still alive. In 405/4 BC, when the Spartan admiral Lysander went around \"liberating\" the cities of the Athenian Empire, he may not have suggested but certainly did not object to several states making him the subject of heroic cult. Many of these states transferred their founder cult to the Athenian Konon when he liberated them from Lysander's oligarchies in turn. By the fourth century BC, it had become established practice for Greek states to lavish ever more extravagant honours on their (military) benefactors - sometimes to the extent of worshipping them as divine founder figures.\n\nPhilip II of Macedon, Alexander's father, had a habit of doing everything that great Greek generals did, but more so. His attitude to founder cult was no different. He not only demanded to be made the subject of heroic cult; he also made sure to found several cities, with the intention of being legitimately worshipped as their actual founder. Most prominently, he re-founded the town of Krenides as Philippoi in 356 BC - making the first city named directly in celebration of its royal founder. The result was that already during his lifetime Philip was regarded as a near-divine figure; he may have been deified after his death.\n\nThis is the practice that Alexander and his successors took up and extended across his vast new empire. It was an easy, legitimate, time-honed way to gain glory and worship, and to bring oneself closer to the gods in the eyes of one's subjects. No doubt it was his pursuit of a name greater than any other that drove Alexander to found city after city on his way east."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/3bzn9c/how_were_cities_founded_by_traveling_armies_in/",
"https://www.reddit.com/r/AskHistorians/comments/6dfnei/in_ancient_times_ive_heard_that_historical/",
"https://www.reddit.com/r/AskHistorians/comments/1i7aqp/who_populated_the_cities_founded_by_alexander_the/"
],
[
"https://www.reddit.com/r/AskHistorians/comments/7p8h79/when_people_think_of_colonisation_they_typically/dsfwy88/",
"https://www.reddit.com/r/AskHistorians/comments/1i7aqp/who_populated_the_cities_founded_by_alexander_the/"
]
] |
|
gyuzv
|
Are we made more of microbes than our own cells, or does the smaller size of bacteria mean that by mass, we're larger?
|
"Eukaryotic cells range in size between 2 and 100 micro meters (=10-6 meters) and are usually much larger than prokaryotic cells which run between 0.5 and 2 micrometers."
[source](_URL_0_)
At the same time, [The number of bacteria living within the body of the average healthy adult human are estimated to outnumber human cells 10 to 1](_URL_1_).
So, by mass, or by volume, are we still more of people than digestive tract biota?
|
askscience
|
http://www.reddit.com/r/askscience/comments/gyuzv/are_we_made_more_of_microbes_than_our_own_cells/
|
{
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"text": [
"By both mass and volume, we are more people than bacteria.\n\nBacteria are much much smaller. The numbers you give there suggest that human cells are about 50x bigger than bacteria. Cells are three-dimensional, so this means a human cell is going to be about 50^3, or 125,000x more voluminous, and roughly that much more massive.",
"Here's some images that can give you a comparison between the size of human / animal cells vs. bacteria.\n\n* [The yellow rods are bacteria](_URL_0_) and the green blob is a whole cell\n* [The smaller spheres are bacteria](_URL_1_) compared to a red and white blood cell\n* [Here's a chart showing the relative sizes of things](_URL_4_). The [average size](_URL_2_) of bacteria is around 1 - 3 μm (micrometers), where as the average size of a [human cell](_URL_3_) is 10 μm. That's 10 times larger for most bacteria.",
"Volume wise, we are more human than microbe. Pure numbers wise, we are more microbe than human. Gene function/transcript? Well, I'd postulate we are still more microbe than human, but I don't know that work nearly as well."
]
}
|
[] |
[
"http://www.slic2.wsu.edu:82/hurlbert/micro101/pages/Chap2.html",
"http://www.sciencedaily.com/releases/2008/06/080603085914.htm"
] |
[
[],
[
"http://www.sciencephoto.com/images/download_lo_res.html?id=662200736",
"http://www.sciencephoto.com/images/download_lo_res.html?id=802660112",
"http://www.biologyreference.com/Ep-Fl/Eubacteria.html",
"http://en.wikipedia.org/wiki/Cell_%28biology%29",
"http://img.imgur.com/CTz5Dl.jpg"
],
[]
] |
|
3mw9f8
|
If we upgraded Hubble with modern tech/optics, how much better would it get?
|
Or would it just make more sense to start from scratch and throw a new telescope out there?
|
askscience
|
https://www.reddit.com/r/askscience/comments/3mw9f8/if_we_upgraded_hubble_with_modern_techoptics_how/
|
{
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"text": [
"That is the plan, the James Webb Space Telescope is about six times the size of Hubble and should go up in about three years.",
"This may help answer your question:\n\n_URL_0_\n\nMost of the answer(s) you need are in the last few paragraphs but it is very interesting to read the maintenance history on this magnificent piece of machinery..."
]
}
|
[] |
[] |
[
[],
[
"https://en.wikipedia.org/wiki/Hubble_Space_Telescope#Servicing_missions_and_new_instruments"
]
] |
|
iovsj
|
What do wild animals do in inclement weather?
|
I was driving during a heavy southern thunderstorm and was wondering about this. What do animals do when the wind is blowing and the sky is falling? Is natural shelter and fur good enough, or do they just hang out in rain and hail without a care? There can only be so much cave space, and I imagine it would be rough on a lot of creatures.
And, now that I think about it, if animals run away from a wildfire, do the new areas they move into suffer as a result of the greater population/different ecosystem?
|
askscience
|
http://www.reddit.com/r/askscience/comments/iovsj/what_do_wild_animals_do_in_inclement_weather/
|
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"text": [
"Get wet.\n\nFeel miserable.\n\nStart to smell.\n\nPossibly be injured and/or die if they can't find shelter and the storm is really bad, just like you would without your house.",
"They would try to find natural shelter in which they would already sleep in/under. It does not affect animals as much as humans because they are accustomed to being outdoors all day (they don't know any better anyway).\n\nI work in the Prairies and I will sit in my truck when it is pouring rain and as an example the cows in front of our truck just sit there in the field like it is a nice sunny day out. It doesn't affect them at all, I would assume most animals are like this.",
"I have seen videos of chimps using large leaves as umbrellas. Cattle (as stated) appear to ignore it completely. cats find shelter, some dogs do. It all depends.",
"It depends on the animal. I was on a trip with llamas once, and there was a tremendous thunderstorm in the night while they were tied up to bushes and things. It didn't seem to bother them - they just hunkered down with their legs folded underneath them and waited it out. In the morning, they were wet on the outside, but if you stuck your hand into their coats they were actually dry underneath the outer layer.\n\nSome animals have no choice. [Muskoxen](_URL_0_) are my favorite example. They live in the arctic, which means that for several months every year it is not only cold and snowy, but also dark. There are no trees to hide under, either - they're basically out in high winds, in the dark, and have to dig under the snow to find food for more than half the year. They survive due to a number of pretty cool adaptations, like their wooly undercoat. Known as \"qiviut\", it's made into some of the most expensive yarn in the world due to its extreme warmth."
]
}
|
[] |
[] |
[
[],
[],
[],
[
"http://www.hww.ca/hww2.asp?id=95"
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|
5kln6a
|
usa mcdonald's franchise owners, operators or managers: what is the purpose of two drive through ordering points for one drive though window?
|
Every time I drive through a McDonald's restaurant with multiple drive through ordering boxes, I try to ascertain why this setup provides any advantage to the restaurant. My personal observations:
1) Lines are still just as long as under the old system
2) My order is always verified by the person taking payment as cars easily get out of order
3) Food receipt time, in my opinion, is as long or even longer than in previous years
4) The serving of the food limits the speed of the line, and ordering faster does not appear to decrease wait time.
I'd love to know the business case for this configuration.
Edit: Punctuation and formatting
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5kln6a/eli5_usa_mcdonalds_franchise_owners_operators_or/
|
{
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"text": [
"Data proves you wrong. Typically the slowest part of the average drive-thru is the ordering process. Customers unsure of what they want, large orders, etc. Years worth of data taken has proven this, that's why they have multiple ordering lanes. It's all about the number of cars they can get through, and having a backup lane maximizes that."
]
}
|
[] |
[] |
[
[]
] |
|
396zuz
|
Would taking cooked meat out of the fridge, warming it, and then putting it immediately back in the fridge make it go bad?
|
My mom has always told me not to do this, but I'm not sure if it's true. If it, what's the reason behind it?
I have a bowl of ground meat that I just warmed and I decided I didn't need it now. I'm not sure whether i can just stick it back into the fridge while it's hot or if I should wait!
|
askscience
|
http://www.reddit.com/r/askscience/comments/396zuz/would_taking_cooked_meat_out_of_the_fridge/
|
{
"a_id": [
"cs1cm75"
],
"score": [
3
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"text": [
"Meat in your fridge contains pathogenic microorganisms. They divide very slowly (if at all) in the cold fridge, but much more rapidly at room temperature. Air in your kitchen also contains pathogenic microorganisms, some of which would grow rapidly on nutrients they can extract from meat. \n\nThese pathogenic microorganisms can hard you in two different ways. Some of them, when ingested, will divide in your body and make you sick. These are typically killed by proper cooking. Some of them secrete toxins that make you sick, and those toxins can persist long after the microorganisms stop dividing or die. These toxins may or may not be destroyed by cooking.\n\nSo, every time you warm meat up, you give the pathogens in it — as well as any that might land on it — a bigger opportunity to grow and secrete toxins that might harm you or kill you. \n\nOn the other hand, most of the risk of those pathogens and toxins is mitigated by properly preparing the meat. \n\nSo if you re-heat the meat to a proper meat cooking temperature later, you will probably be OK. But if you just re-thaw it and eat it, you are putting yourself at higher risk of food poisoning. How high that risk depends on a variety of things, including whether the meat was properly prepared to start with, how long it was left out before being initially refrigerated, as well as how long it was out before being subsequently refrigerated. \n\nIn short: you mom isn't wrong, but you might be OK. I definitely wouldn't make a habit of it."
]
}
|
[] |
[] |
[
[]
] |
|
qh6m5
|
By 1571 how secure was Elizabeth I's hold on the throne?
|
I just need some general points or topics I could cover, or if anyone could point me in the direction of some historiography. Any help is greatly appreciated
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/qh6m5/by_1571_how_secure_was_elizabeth_is_hold_on_the/
|
{
"a_id": [
"c3xl6ms"
],
"score": [
4
],
"text": [
"Not a historian, but I'll give this my best shot\n\n* Strong hold on government and country, she still commanded respect of her council and country\n\n* One could argue that her moderate religious settlements, \"pacified\" the extreme catholics (many preachers were arrested/executed)\n\n* The pope issued a papal bull much later, demanding the Catholics to overthrow the 'illegitimate' and Protestant Queen, but it came too late and nothing really happens \n\n* Although there was a plot to replace her with a Catholic successor (Ridophi plot), Mary Queen of Scots was dealt with (House Arrest), however she still was a 'rally point' for foreign catholics who wish to overthrow Elizabeth\n\nThis is in contrast to 90s onwards which some Historians call the Late Elizabethan crisis, when her ministers (such as Burghley) start dying off, and replaced with more ambitious ones, expeditions/wars (esp. Irish nine years war), and tax burdens (book of rates not updated resulting in insufficient funds), as well as bad harvests and economy created lots of problems for her. "
]
}
|
[] |
[] |
[
[]
] |
|
46179m
|
when you're trying to sleep and you hear something, a flash or some tick in your eye that goes with the sound?
|
Example: I was trying to fall asleep, feeling pretty comfortable and heard my dog get up off the floor. When I heard that the sound it made a quick light while my eyes were still closed appear.
Hopefully this makes sense, thank you!
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/46179m/eli5_when_youre_trying_to_sleep_and_you_hear/
|
{
"a_id": [
"d01ndq4"
],
"score": [
5
],
"text": [
"Chances are you were transitioning into sleep. During this time, many people are prone to a phenomenon called \"hypnogogia\". This can range anywhere from auditory hallucinations such as hearing voices or phones ringing, to visual hallucinations involving dancing blobs or waves of color to seemingly bright flashes.\n\nIf you'd like to know more, check out [this link](_URL_0_)\n\nPersonally, I hear conversations and see color waves mostly. The conversations don't usually make sense. One time I heard a song I really like while my favorite professor passionately lectured while a bunch of demons flew around the room screaming. It can be quite strange, but if you go along, it can be quite a ride.\n\nEdit: Fixed link."
]
}
|
[] |
[] |
[
[
"http://dreamstudies.org/2010/12/10/hypnagogic-dreams-and-imagery/"
]
] |
|
1u79m5
|
the barn-pole relativity paradox
|
Say we have someone hold a pole of length L. A farmer has a barn of length (3/4)L with gates on either side. The farmer bets the pole vaulters that he can make the pole fit entirely inside the barn horizontally. He asks the vaulter to run into the barn with speed (sqrt3/2)c, so the pole contracts relativistically to only (1/2)L and thus fits when the gates are instantly closed according to the farmer. The vaulter, however, observes the barn contracting by a factor of 2, so the pole does NOT fit inside when the gates are closed.
Can someone help me understand the resolution to the paradox? Is the Lorentz contraction "real" in this problem?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1u79m5/eli5_the_barnpole_relativity_paradox/
|
{
"a_id": [
"cef6vhn"
],
"score": [
3
],
"text": [
"Lorentz contraction is always \"real\", but the point is that it's *relative*. The farmer sees the entire pole in the barn, while the runner doesn't (how could he, since for him it's *the barn* that's contacting).\n\nThe resolution of the \"paradox\" comes from carefully considering what we mean when we say \"the pole fits in the barn\". This is shorthand for saying \"the front of the pole exits the back of the barn *after* the back of the pole enters the front of the barn\". So really, when we talk about fitting the pole in the barn, we're taking about the space-time interval between two events. The paradox is resolved because relativity also dictates that the different observers will not agree on the relative timing of the events. \n\nTLDR; Relativity requires us to rethink simultaneity"
]
}
|
[] |
[] |
[
[]
] |
|
72za7r
|
Do humans have a vestigial tail wagging response? Is it detectable?
|
askscience
|
https://www.reddit.com/r/askscience/comments/72za7r/do_humans_have_a_vestigial_tail_wagging_response/
|
{
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"dno0dtj"
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"score": [
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" > A case of a tail in a 2-week-old infant is reported, and findings from a review of 33 previously reported cases of true tails and pseudotails are summarized. The true, or persistent, vestigial tail of humans arises from the most distal remnant of the embryonic tail. It contains adipose and connective tissue, central bundles of striated muscle, blood vessels, and nerves and is covered by skin. Bone, cartilage, notochord, and spinal cord are lacking. The true tail arises by retention of structures found normally in fetal development. It may be as long as 13 cm, \n**can move and contract**, and occurs twice as often in males as in females. \n\n_URL_0_",
"Not really, no. Animals wag their tails for a variety of reasons, but the happy=tail wagging response in dogs is unique to them. (Interestingly, foxes that were domesticated as part of an experiment also began [wagging their tails in greeting](_URL_0_) after several generations of breeding for tameness. So the potential for tail-wagging in excitement and happiness when bred for juvenile traits is present through a lot of the canine family tree.) A cat wagging its tail is most likely annoyed or agitated, or at least overstimulated. There is no hardwired environmental or behavioral reason for tail wagging that all animals share. (EDIT: And yes, a dog can also wag its tail when it isn't happy; I was specifically referring to the common, stereotypical behavior of the happy tail-wagging doggo.)\n\nApes 'lost' their tails at least 14 million years ago, well before the human branch of the family tree had even begun to split. Human responses that involve butt-wiggling (for lack of a more specific term) like dancing or squirming are coming from a different behavioral source that has nothing to do with tails.",
"No.\n\nFirst of all, the coccyx does not retain the muscular functionality of a tail, but it does act as an anchor point for tendons, ligaments, etc. Second, while tail-wagging is a trait present in *some* primates, such as lemurs, it is far from ubiquitous, and there is no evidence of tail-wagging in any of our closest primate relatives.",
"Wouldn't this be similar to laughing or smiling? Yes, you can control this response but it does happen immediately and sometimes uncontrollably especially when greeting someone you have missed. I didn't take your question as is we had internal tails or something but more of a question of an uncontrollable happiness response. \n\nEdit: wait did you mean the people who are actually born with tails? ",
"By tail-wagging, I assume that you are referring to tail-wagging as it is seen in dogs (to my knowledge, primates do not wag their tails; if anybody has evidence to the contrary please correct me). The thing is, humans didn't evolve from dogs or any dog-like species; rather, humans and dogs have a common ancestor which existed over 100 million years ago, which probably did not have a tail-wagging response. The tail-wagging response likely evolved after the evolutionary \"split\" that occurred at our common ancestor with dogs. Your question makes the false assumption that there was a time in our evolutionary history that humans had a tail-wagging response, but that's probably not the case, and you'd have to provide evidence that there was tail-wagging in our ancestors. So, to answer your question, it may be the case that humans have never had a tail-wagging response to \"lose\" in the first place, and for that reason, we probably don't have a vestigial tail-wagging response. ",
"No, but Humans have other limbic reactions that signify happiness pretty much across the board. Watch someone's feet next time they are very excited or happy; it's where the phrase 'happy feet' comes from. Closest thing I can think of to tail wagging ",
"all these answers at the top gave nice scientific responses. but I don't see anybody trying to make the connection between dogs wagging tails and anything humans may do with body language to show happiness/excitement...?",
"Fun fact : some humans (not everyone) have a muscle attaching their sacrum to their ischium (hip bone). It used to be the muscle that was moving our tail horizontally... When we had one ^^\n\nOfc we don't use it anymore and that's the reason why not everyone has one. \"Inconstant\" organs like this are pretty frequent in human body.",
"We do have what's called a \"vestigial\" tail, meaning that it's a sort of evolutionary leftover. It's visible in embryos, but by the time we're born, we just have a few small bones that can't be seen from the outside. Most people don't even know they have tailbones unless they break one. Occasionally, a baby will be born with a tail, but it is usually removed surgically.\n\nWhy did the ancestor of the apes and people lose their tails? No one really knows. Things don't disappear just because they are not being used. One gene can cause many different things. It is possible that a gene that was helpful to this species had a few effects, including the loss of the tail. It is also possible that having a tail came with a price. Individuals that had small or no tails would have been able to leave more offspring with the no-tail gene.\n"
]
}
|
[] |
[] |
[
[
"https://www.ncbi.nlm.nih.gov/pubmed/6373560"
],
[
"https://en.wikipedia.org/wiki/Russian_Domesticated_Red_Fox#Genetic_experimentation"
],
[],
[],
[],
[],
[],
[],
[]
] |
||
14qsat
|
How, when and why was the label "made in [country]" invented? When was it first used and to what purpose?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/14qsat/how_when_and_why_was_the_label_made_in_country/
|
{
"a_id": [
"c7fk6bs"
],
"score": [
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"text": [
"[Made in Germany](_URL_0_), introduced by the British to mark the inferior quality and plagiarising German goods being imported. Quickly turned out to be a boon to Germany instead of a hindrance as originally intended."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Made_in_germany"
]
] |
||
6o3dh6
|
did the musical notes we all know (d,f,g,f-sharp etc.) basically *have* to be or was this just one person's selection that ended up working well?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6o3dh6/eli5_did_the_musical_notes_we_all_know_dfgfsharp/
|
{
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"text": [
"Look at a violin. It has no frets. Violin players play by ear and get it right. So do Bass and viola players. Look at a guitar. It has frets. Guitars have to be tuned. But once tuned they can be played by holding strings down on the frets.\n\nWe need to define what one note is, how many cycles per second. Double that frequency plays the note again an octave up. Halve the frequency and you get the note again an octave lower. \n\nThe other notes are standard ratios away from the first note. Playing the right notes together as a chord is pleasing. They are a certain distance apart by ratios, when played. So they alternately resonate together.\n\nSo once the first standard tone is selected. It is world wide now and easy to tune to, the other notes can be defined.\n\nThat is the simple explanation. When you get more complex you can study [music theory](_URL_0_) and how a piano is a compromise. String instruments are not.",
"Here's the really short explanation: the notes are based in part from ratios between the different notes. For example a note and an octave higher will have a 1:2 ratio, where a note and it's fifth will have a 2:3 ratio.\n\nAgain to summarize, over hundreds of years we figured that having 7 notes made music that sounded very pleasant and we just gave these notes the name A, B, C, D, E, F, G. Other countries have different names for these 7 notes. Think of the white keys on the piano.\n\nHowever transposing these notes up and down and using the circle of fifths, you can sort of cheat and create an arrangement of 12 notes that allows different combinations of 7 notes for many keys. We have to fill in the blanks so we create flats and sharps between the white notes. These are the black keys on the piano.",
"Sound is vibrations and we attribute the frequency of those vibrations a pitch. When certain combinations of frequencies are combined, they may blend together well or not.\n\nFor example, if you have a note with vibration of 256 Hz, and you play a 2nd note with a frequency of 512 Hz, then you get a 1:2 ratio of vibrations, and the two go together really nicely. In general, people call them the same note, but at a different \"octave\"; in this case, 256 Hz is by convention called \"middle C\", and 512 Hz is C one octave above middle C.\n\nBut what about the other notes? Where did they come from?\n\nIt turns out that 1:2 isn't the only ratio that works nicely. 2:3, or 3:4 or 4:5 or 3:5 something similar give pleasing sounds when played together. \n\nSo, if you combined 256 Hz with 320 Hz, that's a nice combination; or 256 combined with 320 and 384 Hz in a 3 note chord is also a nice combiation.\n\nSo, how could you define lots of different notes which made up all these different ratios? One way, would just be to have a 4:5 ratio (320), a 3:2 (384) and so on - and then repeat everything after doubling or halving (640, 768 - or 160, 192). The problem with this, is that the \"gaps\" between the notes are all different - so you can't just take a piece of music and shift it a little bit lower, or a little bit higher.\n\nEventually people worked out, that if you divided the doubling interval into 12 equal steps (each note is 1.06 * the one before - so 256, 271, 287, 304, 322, 341, 362, 384, 406, 431, 456, 483, 512) - you could get close to lots of nice ratios (you can see the 322 which is very close 4:5, 384 which is exactly 3:2, 287 which is very close to 3:4, 431 which is close to 3:5).\n\nThis gives you 12 equally spaced notes with a ton of really nice ratios which can be combined together in nice chords, while at the same time being easy to use with equal notes.\n\nIf you dig down into the ratios - you'll see that starting from \"C\", the white keys on the piano correspond to the nicest ratios - D is 7:8, E is 4:5, F is 3:4, G is 2:3, A is 3:5, B is 8:15; the black keys are in between ratios for example D# is 16:19.\n\nSo it all comes down to discovering that dividing an octave into 12 equal steps results in a lots of nice combinations that \"just work\". People realised that the nicest ratios weren't equally spaced (for example F is next after E, but D has a note between in and C), and that's why there's no E#.\n\nAs to why 256 Hz might be used - there's no real reason. You can choose any reference you want. In fact, people often tune to concert A (440 Hz) which requires a slightly different tuning.\n\nJust one final point: modern tuning normally tunes instruments so that the spacing between the notes is exactly equal. But, as I pointed out above, this doesn't exactly match the nice round number ratios. Historically, instruments were often tuned to give the exact ratios; the tuner would listen to the two notes together, and they'd be in tune when you got the nicest sounding chord. This type of tuning would give nice pure sounding chords and harmony - but this lead to the gaps between the notes not being quite even, and resulted in certain combinations of notes having completely off ratios and sounding weird and clashing (called a Wolf interval)",
"Historically the names of the notes change over time.\nThe root choice for the names of the notes of the western 12 note scale are arbitrary. What is important however it is that all instrument manufacturers at least AGREE on the arbitrary names of the notes. \n\nThe IOS (International organization for Standardization) set the tuning of middle \"A\" to 440 vibrations/second in the early 20th century. This standard is called \"A-440\". It has not always been the case however and pitch changes a lot throughout history.\n\nMozart's \"A\" for example was nearly a semi-tone lower than what we would call an A today. It sounded closer to a G-sharp than an A. If you tried to play a flute from the 18th century with a modern orchestra, you would need to transpose in order for it to work. His names of the notes were indeed different.\n\nStandard pitch really does rise over the years. \"A\" was closer to 428hz at the end of the 1800's, while some orchestras around the world today are tuning as high as A-445. That's a HUGE difference.",
"In addition to what others have said, here are some notes and their corresponding frequencies. The ratio from one frequency to another is always 1.05945....\n\n\n C0\t16.35\t\n C#0\t17.32\t1.0594630944\n D0\t18.35\t1.0594630944\n D#0\t19.45\t1.0594630944\n E0\t20.60\t1.0594630944\n F0\t21.83\t1.0594630944\n F#0\t23.12\t1.0594630944\n G0\t24.50\t1.0594630944\n G#0\t25.96\t1.0594630944\n A0\t27.50\t1.0594630944\n A#0\t29.14\t1.0594630944\n B0\t30.87\t1.0594630944\n C1\t32.70\t1.0594630944\n C#1\t34.65\t1.0594630944\n D1\t36.71\t1.0594630944\n D#1\t38.89\t1.0594630944\n E1\t41.20\t1.0594630944\n F1\t43.65\t1.0594630944\n F#1\t46.25\t1.0594630944\n G1\t49.00\t1.0594630944\n G#1\t51.91\t1.0594630944\n A1\t55.00\t1.0594630944\n A#1\t58.27\t1.0594630944\n B1\t61.74\t1.0594630944\n C2\t65.41\t1.0594630944\n C#2\t69.30\t1.0594630944\n D2\t73.42\t1.0594630944\n D#2\t77.78\t1.0594630944\n E2\t82.41\t1.0594630944\n F2\t87.31\t1.0594630944\n F#2\t92.50\t1.0594630944\n G2\t98.00\t1.0594630944\n G#2\t103.83\t1.0594630944\n A2\t110.00\t1.0594630944\n A#2\t116.54\t1.0594630944\n B2\t123.47\t1.0594630944\n C3\t130.81\t1.0594630944\n C#3\t138.59\t1.0594630944\n D3\t146.83\t1.0594630944\n D#3\t155.56\t1.0594630944\n E3\t164.81\t1.0594630944\n F3\t174.61\t1.0594630944\n F#3\t185.00\t1.0594630944\n G3\t196.00\t1.0594630944\n G#3\t207.65\t1.0594630944\n A3\t220.00\t1.0594630944\n A#3\t233.08\t1.0594630944\n B3\t246.94\t1.0594630944\n C4\t261.63\t1.0594630944\n C#4\t277.18\t1.0594630944\n D4\t293.66\t1.0594630944\n D#4\t311.13\t1.0594630944\n E4\t329.63\t1.0594630944\n F4\t349.23\t1.0594630944\n F#4\t369.99\t1.0594630944\n G4\t392.00\t1.0594630944\n G#4\t415.30\t1.0594630944\n A4\t440.00\t1.0594630944\n A#4\t466.16\t1.0594630944\n B4\t493.88\t1.0594630944\n C5\t523.25\t1.0594630944\n C#5\t554.37\t1.0594630944\n D5\t587.33\t1.0594630944\n D#5\t622.25\t1.0594630944\n E5\t659.26\t1.0594630944\n F5\t698.46\t1.0594630944\n F#5\t739.99\t1.0594630944\n G5\t783.99\t1.0594630944\n G#5\t830.61\t1.0594630944\n A5\t880.00\t1.0594630944\n A#5\t932.33\t1.0594630944\n B5\t987.77\t1.0594630944\n C6\t1046.50\t1.0594630944\n C#6\t1108.73\t1.0594630944\n D6\t1174.66\t1.0594630944\n D#6\t1244.51\t1.0594630944\n E6\t1318.51\t1.0594630944\n F6\t1396.91\t1.0594630944\n F#6\t1479.98\t1.0594630944\n G6\t1567.98\t1.0594630944\n G#6\t1661.22\t1.0594630944\n A6\t1760.00\t1.0594630944\n A#6\t1864.66\t1.0594630944\n B6\t1975.53\t1.0594630944\n C7\t2093.00\t1.0594630944\n C#7\t2217.46\t1.0594630944\n D7\t2349.32\t1.0594630944\n D#7\t2489.02\t1.0594630944\n E7\t2637.02\t1.0594630944\n F7\t2793.83\t1.0594630944\n F#7\t2959.96\t1.0594630944\n G7\t3135.96\t1.0594630944\n G#7\t3322.44\t1.0594630944\n A7\t3520.00\t1.0594630944\n A#7\t3729.31\t1.0594630944\n B7\t3951.07\t1.0594630944\n C8\t4186.01\t1.0594630944\n C#8\t4434.92\t1.0594630944\n D8\t4698.64\t1.0594630944\n D#8\t4978.03\t1.0594630944\n E8\t5274.04\t1.0594630944\n F8\t5587.65\t1.0594630944\n F#8\t5919.91\t1.0594630944\n G8\t6271.93\t1.0594630944\n G#8\t6644.88\t1.0594630944\n A8\t7040.00\t1.0594630944\n A#8\t7458.62\t1.0594630944\n B8\t7902.13\t1.0594630944"
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Music_theory"
],
[],
[],
[],
[]
] |
||
i2u3o
|
Is it possible to harvest gravity (or, more correctly, gravitational waves)?
|
[This Post](_URL_0_), gave me the thought that perhaps it's possible to harvest gravitational waves in a similar manner to the way that solar panels are used to harvest sunlight. I imagine that we would need a material that reacts to the gravitational waves (similar to photovoltaic cells). What do you guys think?
|
askscience
|
http://www.reddit.com/r/askscience/comments/i2u3o/is_it_possible_to_harvest_gravity_or_more/
|
{
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"text": [
"Without reading the article I can assure you that hydroelectric power is a much more efficient way of harvesting gravity.",
"The interaction cross section is way, way too low.\n\nActually, let me amend that:\n\nThe interaction cross section is way, way, way, way, way, way, way, way, way, way, way, way, way, way, way, way, way, way, way too low.\n\nWhen an optical photon hits a piece of silicon at terrestrial densities, the path length it travels before being absorbed is very short. This is quantified by the \"optical depth\" of the medium. As long as you make your silicon a few times thicker than this length, you'll be absorbing all the photons.\n\nOne of the first problems we did in the GW seminar I took a few years ago was to try to calculate the density of stuff you'd need in order to have a certain \"optical depth\" (obviously not optical) for gravitational waves. It turns out that if you want to efficiently absorb gravitational waves, you need a black hole. Gravity is just so freakin weak.",
"The gravitational wave flux we get on Earth is so low that our detectors have to be sensitive to length changes less than the size of an atom. I don't know if we can ever harvest that flux, but I know it would be pointless to do so."
]
}
|
[] |
[
"http://www.reddit.com/r/askscience/comments/hpidb/hey_science_what_would_happen_if_two_black_holes/c1xcpxl"
] |
[
[],
[],
[]
] |
|
53s392
|
Artificial sun by throwing fusion bomb in hydrogen cloud?
|
Hi i was just thinking about random things and I was wondering if we could create a "artificial" sun by throwing a hydrogen bomb in a hydrogen cloud? Are these clouds dense enough or would the bomb just push it all away? And if it was dense enough it would probably form a sun itself(?)
(I know that it's impossible for us right now because of the distance but it's only theoretical)
|
askscience
|
https://www.reddit.com/r/askscience/comments/53s392/artificial_sun_by_throwing_fusion_bomb_in/
|
{
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"text": [
"To sustain a fusion reaction, the combination of temperature and pressure need to be sufficiently high. That's why there is fusion in the sun, but not in Jupiter, which, like the sun, consists of largely hydrogen and helium.\n\nWhen an object like Jupiter doesn't have sufficient density for fusion to sustain itself, a hydrogen cloud won't even come close. Detonating a fusion bomb inside the cloud won't do anything but push the cloud further outward. Just like in the sun, where the fusion reaction exerts an outward pressure. However, in the case of the sun, its gravity is sufficient to counteract the outward force generated by the fusion reaction and the sun doesn't disperse. In a hydrogen cloud, there's no gravity strong enough to keep it from dispersing when sufficient outward pressure is applied (because if there was, the cloud would've collapsed in on itself and potentially formed a star).",
"Stars are stars because of their mass and density, you can't short-circuit that process.\n\nPartly your question likely arises because of a common misconception about the formation of stars, that they are cold clumps of Hydrogen gas until suddenly fusion kicks on and then they light up like a fire. In fact, stars are born hot and bright, even before fusion starts. Gravitational collapse releases a lot of energy, and that energy becomes heat which results in the surface of proto-stars being very hot, at thousands of degrees, and fairly bright as well (due to their large sizes). They need to be bright in order to radiate away that gravitational collapse energy so they can get denser, and, ironically, hotter at their cores. The transition between collapsing proto-star and actively fusing Hydrogen real-star is not at all a dramatic one in the moment, it takes millenia for the star's surface to heat up. Moreover, the star actually becomes more well behaved and less violent as fusion kicks on because the dominant form of heat transport switches to radiation from convection which settles the star into layers of different temperatures and densities."
]
}
|
[] |
[] |
[
[],
[]
] |
|
2kvcmq
|
why is direct democracy not a viable system as opposed to what we have? would it result in massive indecisiveness, if implemented?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2kvcmq/eli5_why_is_direct_democracy_not_a_viable_system/
|
{
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"text": [
"Two main problems with direct democracy I can think of off the top of my head:\n\n- stability: the will of the masses tends to change quickly. News report on minor being raped and killed? Let's introduce death penalty. Mass shooting? Let's forbid guns. Note I'm not taking a stand towards either death penalty nor gun control; just pointing out that recent events will have a major influence on policy in a direct democracy, and that's rarely a good thing.\n\n- power distribution: media influence plays an even higher role than it already does, pretty much for the same reason as above - it can easily sway public opinion.\n\nThis is really a question better suited for /r/askreddit.",
"It would result in what's called the tyranny of the masses (or \"mob rule\"), as the popular majority tramples on the wishes and needs of the minorities.",
"Switzerland, with around 8 million citizens, has a limited but very viable version of direct democracy. It has worked well for a long time, with citizens voting on various issues four times a year. \nOn the federal (country) level, anyone who can gather 50 000 votes within 100 days can force a national vote on whether or not to block specific legislation introduced by parliament. If you can gather 100 000 signatures within 18 months, you can force a national vote on whether or not to introduce changes to the constitution. \nOn the regional (cantonal) and county/city (communal) level, there is even more direct democracy, and citizens can introduce suggestions which will be voted on at the next town meeting.\n\nThe end result of all this is debatable, but what is certain is that Switzerland has become a very succesful country with low taxation, comparatively few bureaucrats, a strong industrial base, and possibly the best health care system in the world."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
4v5a4o
|
Why does fission happen randomly?
|
It seems for a given nucleus either the Coulomb repulsion would overcome the strong force, or the vice versa. From where does probability get involved?
|
askscience
|
https://www.reddit.com/r/askscience/comments/4v5a4o/why_does_fission_happen_randomly/
|
{
"a_id": [
"d5vsfoi"
],
"score": [
14
],
"text": [
"Spontaneous fission is a quantum tunneling process. You have two (or more) \"lobes\" of nuclear matter, bound by a mutually attracting potential. In order for fission to occur, they must tunnel out of their attractive wells. Depending on how strongly deformed the nucleus is, this could be very easy (meaning small lifetime) or very hard (long lifetime).\n\nExactly when tunneling will occur is of course probabilistic."
]
}
|
[] |
[] |
[
[]
] |
|
4hy50v
|
How humans reached islands like Japan during the Paleolithic?
|
Wikipedia reports the first human presence in Japan during the paleolithic (_URL_0_) - how humans reached it (and other islands) ?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4hy50v/how_humans_reached_islands_like_japan_during_the/
|
{
"a_id": [
"d2tdtgc"
],
"score": [
7
],
"text": [
"Hi! While pre-history questions are fine here, it would be worth also x-posting this one to /r/AskAnthropology "
]
}
|
[] |
[
"https://en.m.wikipedia.org/wiki/History_of_Japan"
] |
[
[]
] |
|
16vy2h
|
Why did Bowing die out in Europe, but persist in East Asia?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/16vy2h/why_did_bowing_die_out_in_europe_but_persist_in/
|
{
"a_id": [
"c7zvq3z"
],
"score": [
6
],
"text": [
"Just for some clarification do you mean archery? Or just making the bows?\n\nEdit: I may have misread that, did you mean bowing as in the gesture? If so I appoligize."
]
}
|
[] |
[] |
[
[]
] |
||
1mlky7
|
How was Malta able to withstand the Malta blitz?
|
From what I have read Malta took an incredible beating from Axis bombers during WW2. For such a small island how was it that the urban areas were not completely leveled? Even more so how did the airfield and port facilities, which would be obvious targets, manage to keep running?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1mlky7/how_was_malta_able_to_withstand_the_malta_blitz/
|
{
"a_id": [
"ccafxxf"
],
"score": [
2
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"text": [
"Largely this was due to bombing being much less accurate than you might think. During WWII the percentage of bombs that hit anywhere near their targets was in the single digits--at least when it came to high level strategic bombing. Tactical bombers, such as the (in)famous Stuka dive bomber, could be much more accurate but were also much more vulnerable to antiaircraft fire and opposing fighters. The result was that while it was not pleasant by any means to be a target of aerial bombardment it was also not as damaging as one might suspect, especially to individual targets.\n\nIn the case of Malta, the sources I have read point to the largest difficulty being resupply rather than aerial bombardment. Sam Moses writes about this in his book, *At All Costs: How a Crippled Ship and Two American Merchant Marines Turned the Tide of World War II.* This book describes Operation Pedestal, which took place in 1942. This was a critical supply convoy, in which only five of the original fourteen ships made it to their destination in Malta due to incessant German attempts to stop it. The threat as described by Moses was that Malta would be kept from being resupplied, not that it would be bombed into submission. Subsequent efforts would keep Malta supplied by sea.\n\nThe aerial campaigns against Malta were no doubt damaging. There is even the legendary (and slightly overhyped) story of Malta being defended by a mere three biplane fighters against the might of the Luftwaffe. While there were three such planes, they were joined by modern British fighters as well. These planes along with antiaircraft guns kept the bombing runs from being unopposed. In addition, the Germans never had a force of heavy four engined bombers that could carry heavy bomb loads to their targets. Instead, lighter two engined bombers had a limited bomb load, which certainly limited the damage they were capable of inflicting. They also had little in the way of defensive armament when compared to Allied heavy bombers. So, while they were able to inflict casualties and destroy some buildings, German bombers were unable to knock out Malta's airfields or port facilities. As such, Malta was able to withstand the German bombardment."
]
}
|
[] |
[] |
[
[]
] |
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2s5kg3
|
Suppose I visited Oregon in 1000BCE and then again in AD1000. (Without asking someone) How could I tell which was which?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2s5kg3/suppose_i_visited_oregon_in_1000bce_and_then/
|
{
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"text": [
"People, remember that this is askHISTORIANS, not askpaleoastronomers or askgeologists or askbotanists. If you do not have the proper historical knowledge to answer this question, don't answer.",
"Note to Moderators: if I've made some mistake in the rules please let me know and I'll make an adjustment. I mostly lurk here, but I understand you're quite strict and I'd hate to have this all deleted.\n\nHey there,\n\nGo ahead and cross post this to /r/askanthropology because they will have the experts you need.\n\nSecond, consider explaining why you've asked this question, because there may be some more interesting factoids if you expand your range of time a little bit. Both 1000BCE and 1000CE fall within the Late Holocene (1500BCE-1775CE). \n\nThe Northern Pacific cultures we are familiar with today (thanks Franz Boas!) were well on track by 6,000 years ago. By 1800BCE there were already simple ranked societies (as a cultural anthropologist I tend to buck the archaeological terminology such as 'simple' but I'll do my best to repeat what the textbooks tell you). Essentially because food resources like salmon were extremely seasonal, society stratified into hierarchy by necessity in order to create effective food storage and dispersion over the year. \n\nFollowing 1800BCE, ranking became continually more elaborate. Households tended to be matrilineal (organized around ties to one's mother, her mother, etc) although social units were headed by men. Farther south (which I believe includes Oregon in the context of my reading) there were some episodes of patrilineal households and ranked polygamy, but generally these systems were more unstable. Boom and bust. Again, I'm no expert, but ~~I'll have to disagree with wildfire's comment below and say that you'll probably see planked cedar houses and possibly totem poles as early as 1000BCE. Their prevalence and elaboration is another matter~~(yeah, nope). On a side note, the issue with this whole area/time period is that sea levels rose dramatically and most likely destroyed the vast majority of available evidence, leaving archaeologists with shell middens and the houses of weirdos that built far away from shore. \n\nTo more directly answer your question: The more evidence you see for ranking and heirarchy, the later you probably are. One smoking gun might be the creation of burial mounds. A few of these were undertaken in the area around 1000CE, but there were none before that as far as we know. Burial mounds are large heaps of earth. It's unlikely you would catch anyone in the act of making them (they're actually quite fast to make) but you might see signs of a large mass of disturbed earth that doesn't match the geological terrain. However, I think you would be lucky to run into one because my impression is that they were quite rare. Better to just make some friends and watch for signs of heightened hierarchy (some people have more free time, specialization, accumulation of wealth, competition between groups).\n\nAgain, try cross posting to askanthrpology because you'll be much more likely to get an expert on those date ranges in that subreddit.\n\nThanks!\n\nEdit: [SOURCE.](_URL_0_)\n\nEdit 2: Putting the moderator note on top...\n\nEdit 3: /u/retarredroof gives a great critique of what I've said here (see below). In particular I want to draw attention to a possibly much more foolproof means of answering the question which they point out. Technology is always the archaeologists go-to, and leave it to a cultural anth guy to totally overlook this in favor of nebulous social relationships which there is less evidence for:\n\n > The main difference I would anticipate between 3000 years ago and 1000 years ago on the Oregon coast would be the increased use of the specialized technologies for salmon and other anadromous species (e.g. salmon dams, fish nets, fish and lamprey traps, composite harpoons) and the onset and/or adoption of the classic NW Coast village with the use of large coastal towns by 1000 years ago. Lyman sees a transition from pit houses, like those that persist in interior Oregon until contact, to plank houses during the period of interest on the coast. Social stratification increases through time and it would not surprise me if slavery was in use by 1000 years ago. Also during this period there is a slow transition from flaked stone technology to ground stone use for harpoon and other points.",
"You might not care, but I thought I'd mention that you're mixing dating systems.\n\nBCE goes with CE, and refers to *Before the Common Era* and *Common Era*, whereas BC goes with AD, and refers to *Before Christ* and *Anno Domini*.",
"Since the topic doesn't specify which part of Oregon we're talking about here, I can give some perspective on the Great Basin portion of eastern Oregon (whereas most of the posts have dealt with coastal Oregon).\n\nThe Great Basin is a semi-arid environment where the archaeological record supports a continuous record of hunter-gatherer lifestyles from at least 10,000BP into historic times. This seemingly unchanging record led some of the early researchers to believe that there was no culture change in this region throughout prehistory, but archaeologists now know that this was not the case.\n\nIn the time periods you have designated (3,000BP to 1,000BP) there are actually some quite significant changes in the way that people lived.\n\n1) The shift from atlatl and dart to bow and arrow technology.\nThis is evidenced by the reduced size in projectile points and the cases of preserved bows that have been found in similar contexts. I think the most commonly attributed date to the introduction of the bow is around 1,350BP in the Great Basin. The bow and arrow changed the game of hunting, it made individual hunters more viable whereas the atlatl likely required a group effort. The bow was also more accurate, which made hunting (a costly endeavor compared to seed procurement) more efficient. In some areas, the switch to arrow points reduced the amount of raw material procurement, and thus settlement patterns, as these smaller points required less material to make, but this was primarily in areas where obsidian and other high quality toolstone were rare. The northwestern basin has many obsidian sources, so I doubt this was the case here.\n\n2) Settlement and subsistence.\nI don't know too much about this in Oregon specifically, but I will be talking about the patterns seen just about 50 miles south of the Oregon border. I wouldn't be surprised if the exact same things were happening further north at the same time, or at least something very similar.\nSomewhere between 1,300BP and 1,000BP we begin to see the intensification of upland food resources, primarily roots. Previously, the uplands were mainly hunting grounds, evidenced by older remains being that of hunting material (projectile points). During this period, we see an explosion of ground stone tools (millingstones and handstones). It is absolutely everywhere in late period sites and almost nonexistent in earlier sites. Roots are fairly abundant in these upland areas and it appears that they were incorporated into the diet in a big way. Not to get into optimal foraging or diet breadth too much, but for one reason or another these lower ranked resources presumably had to be added to the diet. Depletion of higher ranked resources, environmental conditions, population pressure are all reasonable explanations.\n\n3) The Numic Spread.\nI'm getting a little ahead of myself with this one, but I think it's worth mentioning. One of the major problems researchers faced in the Great Basin was explaining how the Numic language group had managed to become so widespread (essentially the entire Great Basin and then some at historic times) without significant divergence. Glottochronology would suggest that this language group had not spent all that much time apart from each other. In this case, the Numic hunter-gatherers were a recent inclusion into the Great Basin and spread across it rather quickly. Since we have an archaeological record dating back 10,000 years this means that the Numic speakers must have displaced the previous inhabitants of the Great Basin.\nThe most convincing argument states that the Numic expansion began about 700BP from southeastern California. While some have argued that the expansion began earlier (perhaps 1,500BP), and some MUCH earlier (4,000BP), the aforementioned date of 700BP is the one best supported by glottochronology and the archaeological record. So as I said, I was getting ahead of myself since this doesn't particularly pertain to the dates in this question. Most evidence points to Numic speakers arriving in the northern Great Basin damn near historic times (300-200 years ago). The reason I included this was to illustrate just how variable prehistory could be in the Great Basin, even when discussing the seemingly \"simple\" lives of hunter-gatherers.\n\nSo if you visited eastern Oregon in 3,000BP you would have seen a more sparsely populated area who's inhabitants hunted with the atlatl and focused primarily on lowland seeds and big game animals for subsistence.\nIf you revisited this same area two thousand years later you would likely notice that the population density had increased, higher ranked resources (big game animals) were largely depleted, and encampments in the uplands had become common. Ground stone tools had become much more common and they were used for intensive processing of roots. The atlatl has been replaced with the bow, and while it has made hunters more successful, there is now less to hunt. Smaller game is likely being pursued at much greater rates with the depletion of larger game.\nLater in time, you would see a new ethnic group moving into the area and out competing the previous inhabitants. Some warfare may be present, but it appears that these intruders are simply better adapted to the conditions of the habitat. Using specialized technology for seed processing, the intruders would drive out or assimilate the previous inhabitants with their superior exploitation of the natural resources.\n\n\n\nBettinger, Robert L., and Martin A. Baumhoff\n1982 The Numic Spread: Great Basin Cultures in Competition. American Antiquity 47(3): 485–503.\n\nBettinger, Robert L., and Jelmer Eerkens\n 1999 Point Typologies, Cultural Transmission, and the Spread of Bow-and-Arrow Technology in the Prehistoric Great Basin. American Antiquity 64(2): 231–242.\n\nDelacorte, Michael G.\n2002 Late Prehistoric Resource Intensification in the Northwest Great Basin. In Boundary Lands: Archaeological Investigations Along The California-Great Basin Interface, edited by Kelly R. McGuire, pp 41-48\n\nI apologize if this was a difficult read. Its my first post to AskHistorians and I really rushed it to get it done before bed. There was a lot more I could have covered, so I may revisit this post tomorrow. Hope it was interesting to at least one other person!"
]
}
|
[] |
[] |
[
[],
[
"http://www.amazon.com/Archaeology-Native-North-America-Dean/dp/013615686X"
],
[],
[]
] |
||
3fhurf
|
how can the us government tack on extra laws to bills?
|
I was watching the news and I saw a story about Rio Tinto opening a new mine in Arizona but the native Indians were protesting it because the land had cultural value.
Back in the 50's President Eisenhower passed a law protecting the grounds but a while back a law was sneaked into a bill about military spending which needed to be passed that overruled the law Eisenhower set out. This isn't the first I've heard of it either.
So my question is, How can the government sneak extra (usually controversial) laws into completely unrelated bills without public consultation? Doesn't it defeat the purpose of a democracy?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3fhurf/eli5_how_can_the_us_government_tack_on_extra_laws/
|
{
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"ctor04t"
],
"score": [
2
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"text": [
"People in the US don't vote on every bill that is to/might become law. It is a Representstive Democracy so they vote for Senators and Congresmen/women who will they represent them. It is these people who then vote on the bills which are put before them. If the bill passes in both the Senate and the House of Representatives the president will sign that bill and it will become law. Each bill is not limited to one topic. It is quite often that a bill will be mostly about one topic that everyone can get on board with, and then have a line or section which covers something entirely different. Typically the subject of that provision is something one or the other parties does not particularly want. "
]
}
|
[] |
[] |
[
[]
] |
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70clmz
|
how does recycling paper work and why does it seem like every recycled paper bag is brown?
|
I got a present that was in a Whole Foods bag that said "This bag is made from 100% recycled paper and is completely recyclable." How do my old mail and papers and things become this bag and why do all these recycled bags and things tend to be brown?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/70clmz/eli5_how_does_recycling_paper_work_and_why_does/
|
{
"a_id": [
"dn28fmd"
],
"score": [
6
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"text": [
"Paper is recycled by chopping it up and then cooking the bits in warm water, then mashing them back into sheets and drying it again.\n\nUsually they bleach it, so most recycled paper is white. If they don't bleach it, the natural color is gray or brown depending on the materials. (Brown if made of cardboard boxes, gray if made of office paper or newspaper.)"
]
}
|
[] |
[] |
[
[]
] |
|
10rre5
|
why will a whole flock of birds sit in a tree and caw/chirp/exclaim at seemingly nothing?
|
Saw a big tree just full of black birds the other day - crows, I'd imagine? - and they were all just crowing away. There was nothing around, but I could hear them long before/after I'd walked past the tree. I understand birds making sounds to alert others or otherwise communicate, but what prompts them to all just sit in a tree and make noise seemingly for the heck of it?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/10rre5/eli5_why_will_a_whole_flock_of_birds_sit_in_a/
|
{
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"text": [
"Birds do four very basic things: Eat, sleep, shit and fuck. If the birds have eaten and got enough rest there is nothing left for them to do but try to get with the lady birds. Birds hang out in trees and chirp and sing to show that they have done all the important things and they would be a good choice for a marathon sex session because they are such efficient hunters and sleepers, they must be better than the other birds. Trouble is, once one bird starts making noise, others join in even if they are a bit hungry. Soon all the birds are cawing and whistling outside your door. ",
"There are other reasons to communicate than danger. Social hierarchy, mating selection, etc."
]
}
|
[] |
[] |
[
[],
[]
] |
|
8g82yq
|
What are the horizontal bands of clouds that form during a nuclear detonation, and why do they form at those intervals?
|
[Here’s a video](_URL_0_) showing the US’ largest ever test detonation, with the cloud rings clearly defined.
Thanks!
|
askscience
|
https://www.reddit.com/r/askscience/comments/8g82yq/what_are_the_horizontal_bands_of_clouds_that_form/
|
{
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"dyas7gf"
],
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"text": [
"It's called a condensation cloud, or a Wilson cloud. It only occurs in humid air. With an explosion of significant size, a shock wave develops which leaves a a low-pressure zone behind it. This leads to large-scale adiabatic cooling. This cooling of the air below the dew point allows the moisture to condense into clouds, oftentimes as rings as we see in the video you linked. Once the pressure equalizes, the clouds disappear. How the clouds appear depends on the exact nature of the shock wave as well as the temperature and humidity of the air around the blast."
]
}
|
[] |
[
"https://m.youtube.com/watch?v=T2I66dHbSRA&ebc=ANyPxKoNRWu2B7dEUjvQL1puLtN7GkMqKJeGPQ1STUvTZnrk19XW9FH-KDmRTUIoDD0-hmUY6q1w"
] |
[
[]
] |
|
39vu16
|
When did brothels start using red lights as a sign of their presence? Why red?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/39vu16/when_did_brothels_start_using_red_lights_as_a/
|
{
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"cs7k8aa"
],
"score": [
2
],
"text": [
"Ooo!.Ooo! I know! At least, what they claim in *Brass Checks and Red Lights*, a brief study of prostitution in the late West, and some of the background of sportin' houses. They said it originally came from railroad men hanging their red-glassed lanterns outside the one-whore cribs. However, I have long wondered just how many stops those guys were making to provide that many red lights, and just how old the term actually is. This book would make it post-1830s at the earliest and more like post-Civil War."
]
}
|
[] |
[] |
[
[]
] |
||
13flsq
|
During the middle ages in Europe, how would soldiers treat and transport their weapons and armor from battle to battle?
|
For simplicity, I'm defining middle ages as that broad 1000 years between the fall or Rome and the Renaissance.
For instance, would spears be strapped on their back for long distance travel, or would they typically carry them in hand?
Would knights always be armored when they were not expecting battle?
How were siege engines transported?
What processes were used to keep weapons and armor in fighting order? Was it up to the soldier, or would there be a specialist in an army?
How did this change between the beginning and the end?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/13flsq/during_the_middle_ages_in_europe_how_would/
|
{
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"text": [
"Some shields were equipped with a strap known as a guige used for carrying over the back outside of battle. They're depicted, infrequently, in the Bayeux tapestry, as the Normans travel. More often they're shown holding the shield by the enarmes, the straps that go around the forearm.\n\nEDIT: cleanup",
"I only feel qualified to answer one of your questions. It's not much, but I hope it helps somewhat. \n\nKnights would typically not be armored when not expecting battle. As anyone who has walked around in chainmail can attest; that stuff is very heavy. Add plate and it gets even worse. With training, it's well possible to wear it for an extended time, but sleeping in it would be very uncomfortable and any strenuous activity such as marching would be for more exhausting than it otherwise would be. Both hot and wet weather can make wearing armor even less pleasant. \n\nA good historic example of this can be found in the battle of Stamford Bridge. The vikings had left their armor behind in their ships, because of the hot weather and the fact that they were not expecting conflict with the English for a good while yet. They got a nasty surprise after Harold Godwinsson force-marched his army north in record time.\n\nsource: _URL_0_",
"I'd imagine spears were held with one hand and propped against the shoulder. I've never heard of or seen any depiction of spears being strapped to the back. Knights and men-at-arms on horseback would carry their lances vertically with the butt of the lance resting on the foot or stirrup and held in the middle. They would often attach pennants or banners to the lance so it would flutter overhead when held like this.\n\nWhile on campaign knights would pretty much live in their armor, especially when knights wore primarily mail. An attack to come at any moment and to be caught unarmored would be a bad thing. Also, keep in mind knights almost universally traveled on horseback so the weight of the armor wasn't as much of an issue. While at home they wore what the rest of the nobility wore, the style and type of clothing worn varied with fashion and era.\n\nMost siege engines were built on site from materials on hand and they tended to be crude; rams, towers, catapults etc. Some engines were built beforehand and brought with the army disassembled in carts in the baggage train, things like large trebuchets and cannons, then assembled by the engineers once the city or castle had been invested. The largest trebuchet ever built was the Warwolf, built on the orders of Edward I of England for the siege of Stirling Castle, filled 30 wagons when disassembled.\n\nSoldier is pretty generous term for most members of medieval armies. Most of the foot was comprised of levied peasants armed with whatever implements they could fashion into rude weapons. They were completely responsible for their arms and equipment. It wasn't until the very end of the medieval period that professional armies began to emerge. As for maintenance of equipment IIRC armies would either bring their own armorers, fletchers, bowyers, etc. with them or utilize the services of local craftsmen. I don't know about then but now swords and armor when not in use are packed in mineral oil to prevent rusting. I doubt they had access to mineral oil then so they probably used something like an oil cloth to keep moisture out.",
"Halberds, lances and the like were transported shouldered, with additional equipment wrapped around them. [In this picture from 1513](_URL_0_) you can see some swiss infanterists of the early 16th century on their way to Italy."
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Battle_of_Stamford_Bridge"
],
[],
[
"http://upload.wikimedia.org/wikipedia/commons/5/52/Reislaeufer_Luzerner_Schilling.jpg"
]
] |
|
2jtbtu
|
why are there leaked pictures of almost all new non-released products? how do they get them?
|
Products like Apple iPhones, gaddets and stuff like that... Companies do this on purpose?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2jtbtu/eli5why_are_there_leaked_pictures_of_almost_all/
|
{
"a_id": [
"clevf6s",
"clevhiw"
],
"score": [
6,
3
],
"text": [
"1. an insider (employee, someone in the production line / supply-chain line) sells the information to a publisher.\n\n2. the company itself tries to mimic the hype of \"leaks\" by willfully creating the above for the purpose of marketing.\n\n",
"To announce a new product, it generally helps to have promotional materials already made - stock photos, spec sheets, comparison charts. Also a prototype likely needs to already be made, or even thousands of units may have already been produced and ready to hit shelves. \n\n If you're going to announce a new iPad, you should release the size/dimensions to the authorized case and peripherals manufacturers so they have time to create add-on products. If you're releasing a new version of Windows, you should have a beta version that software developers can make sure their products run on.\n\nAt some point in the process, despite being expressly forbidden from leaking the information, someone decides to sneak it out and expose it. I don't believe \"most\" is \"done on purpose.\" Some of it might be. It's more likely that when you have dozens, hundreds, or thousands, of people working to release a hugely anticipated product, someone is going to leak. \"Two can keep a secret if one of them is dead.\""
]
}
|
[] |
[] |
[
[],
[]
] |
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