q_id
stringlengths 5
6
| title
stringlengths 3
301
| selftext
stringlengths 0
39.2k
| document
stringclasses 1
value | subreddit
stringclasses 3
values | url
stringlengths 4
132
| answers
dict | title_urls
list | selftext_urls
list | answers_urls
list |
|---|---|---|---|---|---|---|---|---|---|
2rkxgq
|
Why are there so many books on Rome, Greece, and Egypt, but hardly anything on Persia?
|
There's tonnes of stuff on those three, but I have never even so much as seen a book dedicated to Persian society or culture. It's like a total blank comes up unless it's related to the Greco Persian war. I have a rough idea of what Rome, Greece, and Egypt were like because of the amount of art and books I find on them, but I know nothing about Persia. Also there are tonnes of stuff on Greek and Greek philosophers and historians, but I don't know anything about Persian ones. Is there any source dedicated to Persian history?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2rkxgq/why_are_there_so_many_books_on_rome_greece_and/
|
{
"a_id": [
"cnh391b",
"cnh9x9m"
],
"score": [
8,
3
],
"text": [
"Part of this is simply what we find in popular literature. Because the classical past is very prominent in western memory and is a \"prestige\" topic it is easier to sell and publish books on the topic; in addition there are simply more people out there with the background needed to write on Greece and Rome. Egypt is less prominent in the \"Western Past\"(a terrible term but we'll use it) but its monumental architecture and spectacular funerary practices have given the subject a considerable public appeal as well. Having said that, there are a considerable number of very fine books on Persian history before the Islamic conquests. Weishofer's _Ancient Persia_ is a commonly recommended general overview of Persian History from the Achaemenid Empire to the Islamic conquests. For further reading on the Achaemenid Empire in particular, Briant's _From Cyrus to Alexander_ remains so far as I know the standard treatment of the subject, with a extensive bibliography on more detailed topics in the field. ",
"I don't have sources for this answer, so feel free to delete, but here are some general possibilities:\n\n1. Linguistical access. Roman texts were written in Latin, a lingua franca in Europe for a longtime. Scholars would have been familiar with Latin and this helped some of the revivals of interest in the Romans that occurred during various periods of European history. I am speculating, but I am guessing a European monk/scholar would be more likely to be able to read a Latin text than one written in a Persian script. \n\n2. Another linguistical point- Greek. Many early New Testament accounts were written in Greek. A familiarity with the language was important to many European scholars in a way that is not the same with any Persian script.\n\n3. Cultural continuity- Many western cultures have seen themselves as extensions of the Romans or Greeks. In the United States, the Founding Fathers were very interested in the classics. This is reflected in the Neoclassical architecture of the time(See Monticello or the Capital) and even the United State's motto was in Latin originally. The sense of being connected to the Romans or Greeks I think has generated more interest and scholarly work in the west than the Persians. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
36qfzc
|
How does the heat from the sun reaches the earth? Are the rays of light emited by the sun hot?
|
How can the rays of light "hold" the heat? If the rays are hot why is the temperature of the Himalaya so low? How much of the heat at the sea level is produced by the friction betweent he rays of the sun and the particles of air?
|
askscience
|
http://www.reddit.com/r/askscience/comments/36qfzc/how_does_the_heat_from_the_sun_reaches_the_earth/
|
{
"a_id": [
"crg77q7",
"crg78qn"
],
"score": [
4,
3
],
"text": [
"Yes the rays are hot as in they carry a lot of energy. This energy is in the end what is captured by the earth and the plants and the solar cells to turn into other forms of energy. There are two reasons why the temperature in the Himalayas is still lower:\n\n* First of all the energy of this beam does not really depend on how far it has traveled. This because the air does not absorb a lot of its energy. The energy density will slightly decrease (since the rays are divergent) but comparing the height of the Mt. Everest (~9km) to the average distance from the earth to the sun (~100M km) this effect will be negligible. So the energy of the rays is the same at both positions\n\n* However energy is proportional to pressure, and the pressure decreases with altitude. This because temperature is nothing more than the average velocity of the particles. With more particles more particles will bump into you and in this way transfer energy to you. This is why in the Himalayas it's cold.\n\nSo for your second question: it's not so much \"friction\" (friction is not really the right word) between the rays and air, it's between the rays and more solid (absorbing surfaces), these surfaces will transfer the heat to the air, which will in turn transfer it to you.",
"The rays of the sun carry energy. When they hit the surface, they are absorbed and that specific spot on the ground receives that energy. The energy is dissipated as heat.\n\nThere is no \"friction\" between light and matter, simply light travelling in matter loses energy to the medium progressively.\n\nThe himalayas aren't colder because they are closer to the sun or anything like that. The air is (in the lower part of the atmosphere) colder as you get to higher altitudes. This is because the atmosphere does not get significantly warmed up by sunlight, but mostly from the earth itself from below, which in turn is warmed by incoming sunlight."
]
}
|
[] |
[] |
[
[],
[]
] |
|
1lmsf9
|
What would happen if you tried to manipulate a rod of material that was a lightyear in length?
|
Say you had a lightyear long pole, and you wanted to poke something a lightyear away, if you tried to pome it with the pole, what would happen?
Would any other interactions/ manipulations produce interesting effects?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1lmsf9/what_would_happen_if_you_tried_to_manipulate_a/
|
{
"a_id": [
"cc0sjxu"
],
"score": [
7
],
"text": [
"Just _some_ of the times the same question has been asked before:\n\n[If I pushed a button 10 light years away with a stick that was 10 light years long, how long would it take for the button to be pushed?](_URL_5_)\n\n[If I have a theoretical rod that is 1 light-year long and I have the ability to pull it one meter towards me, will the opposing end pull away from an observer at the same time or would there be a delay?](_URL_0_)\n\n[If I have a string that is one light year long](_URL_2_)\n\n[If you had a pole 2 light years long on supports would the friction stop you from pushing/pulling it?](_URL_3_)\n\n[If I were floating in space next to a 1-light-year-long metal rod, and I pushed the end of the rod forward one meter, would the far end of the rod move one meter instantly?](_URL_4_)\n\n[If I had a pencil that was 2 light years long, and I managed to use it to write a message on another planet, would I be achieving FTL communication?](_URL_1_)\n\n"
]
}
|
[] |
[] |
[
[
"http://www.reddit.com/r/askscience/comments/11o07k/if_i_have_a_theoretical_rod_that_is_1_lightyear/",
"http://www.reddit.com/r/askscience/comments/s7xat/if_i_had_a_pencil_that_was_2_light_years_long_and/",
"http://www.reddit.com/r/askscience/comments/ke1qx/if_i_have_a_string_that_is_one_light_year_long/",
"http://www.reddit.com/r/askscience/comments/iffn3/if_you_had_a_pole_2_light_years_long_on_supports/",
"http://www.reddit.com/r/askscience/comments/19vec6/if_i_were_floating_in_space_next_to_a/",
"http://www.reddit.com/r/askscience/comments/gwtyt/if_i_pushed_a_button_10_light_years_away_with_a/"
]
] |
|
38sd6o
|
how much luck is involved when something goes viral on social media? besides the merits of the content itself, what other factors contribute to it?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/38sd6o/eli5_how_much_luck_is_involved_when_something/
|
{
"a_id": [
"crxg5fk"
],
"score": [
3
],
"text": [
"You normally need a key person to comment or forward it. Someone who is followed or read by lots of other people to start a kind of cascade effect. A single comment by someone like George Takei will send an ordinary item into a potentially viral one"
]
}
|
[] |
[] |
[
[]
] |
||
7jk2ao
|
would we still get hungry if everything our body needs is directly pumped into our bloodstream?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7jk2ao/eli5_would_we_still_get_hungry_if_everything_our/
|
{
"a_id": [
"dr6xskx"
],
"score": [
2
],
"text": [
"There is TPN, total parenteral nutrition. It is expensive. Everything you need is pumped into the bloodstream. They are very prone to getting infections. It is a big catheter. \n\nPatients getting getting TPN are generally very sick. They do not complain about being hungry. But it could be that they are sick."
]
}
|
[] |
[] |
[
[]
] |
||
2t8y6j
|
if it is illegal to hire someone base on race, why does job applications still have you choose what is your race, why does it matter?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2t8y6j/eli5_if_it_is_illegal_to_hire_someone_base_on/
|
{
"a_id": [
"cnwtm50",
"cnwtojc"
],
"score": [
5,
5
],
"text": [
"Background information is used by HR departments for tracking purposes internally and isn't used for hiring. Legally any racial/personal information must be removed from the application before being forwarded to hiring officials. Also, offering that information is purely voluntary and can't be held against if you choose not to disclose it.",
"In the US, employers are required to keep track of the race of every single person that applies for a job with them.\n\nIf the employer is ever sued for disparate impact discrimination, these records will become evidence in the case."
]
}
|
[] |
[] |
[
[],
[]
] |
||
cg2kof
|
1 out of 10 men are direct descendants of genghis khan. why men specifically? is it impossible for women to be direct descendants?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/cg2kof/eli5_1_out_of_10_men_are_direct_descendants_of/
|
{
"a_id": [
"eue50a3",
"eue61q3"
],
"score": [
17,
9
],
"text": [
"Male descendants are just much easier to trace, because it has to be the same Y chromosome.",
"It's just easier to trace.\n\nHumans have two sex chromosomes - X and Y. Females have XX while males have XY. When a male is conceived, it can get either of the X chromosomes from his mother, but only the one Y chromosome from his father. Therefore, with the exception of random mutations, the entire male bloodline has the exact same Y chromosome.\n\nIf a group of people has the same (or very similar) Y chromosome, then this indicates they might have all descended from the same original male."
]
}
|
[] |
[] |
[
[],
[]
] |
||
99v1nn
|
in southern countries, was north originally considered south?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/99v1nn/eli5_in_southern_countries_was_north_originally/
|
{
"a_id": [
"e4qo7c7"
],
"score": [
3
],
"text": [
"[it's arbitrary. ](_URL_0_) There are historical occurrences of maps that are \"upside down\". So even though \"north\" meaning toward the North Star or magnetic north is always the same direction the way you choose to draw it on a map is up to you. It could just have easily been on the left or right side of the map instead too. \n\nEdit: to better answer your actual question though it's because the dominant countries at the time maps were becoming standardized wanted to be \"on top\". "
]
}
|
[] |
[] |
[
[
"http://america.aljazeera.com/opinions/2014/2/maps-cartographycolonialismnortheurocentricglobe.html"
]
] |
||
24f6y5
|
Are cancerous cells ever observed in non-animal organisms such as plants, fungi, etc...?
|
askscience
|
http://www.reddit.com/r/askscience/comments/24f6y5/are_cancerous_cells_ever_observed_in_nonanimal/
|
{
"a_id": [
"ch73ufd"
],
"score": [
3
],
"text": [
"Yes, plants can form tumors, but in general it is thought they are not as harmful as in animals because plant cells have cell walls while animal cells don't. Similar pathways lead to plant tumors as in animal tumors (ie they develop from stem cell niches). But, one of the key steps in cancer metastasis in animals is the interaction between the cancerous cell and the extracellular matrix surrounding the cell. In plants, due to the rigidity of the cell wall, the cancerous cell has very little room to grow and metastasize, and the cell wall is thought to be critical for the proper development/maintenance of the plant.\n\nSource:\n_URL_0_"
]
}
|
[] |
[] |
[
[
"http://www.nature.com/nrc/journal/v10/n11/full/nrc2942.html"
]
] |
||
1ji6i5
|
What are the earliest examples of a North/South divide in England?
|
By this I mean the notion of an administrative/cultural centre in London that is separated meaningfully from the northern parts of the country? Examples of early resentment, if any can be found, would be appreciated.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1ji6i5/what_are_the_earliest_examples_of_a_northsouth/
|
{
"a_id": [
"cbf1yzi"
],
"score": [
2
],
"text": [
"This cultural / administrative divide can be traced back at least as far as 11th Century. \n\nIn the reign of Edward the Confessor, Northumbria was regarded as a bit of a wild backwater and was never visited by Edward in his entire reign. Indeed, their own Earl Tostig Godwinson spent a large part of his time in Southern England, at court. Unsurprisingly, this state of affairs was unpopular with Northumbrians, who eventually mounted a minor rebellion that resulted in the death of some of Tostig's lieutenants. Eventually Northumbria chose their own earl: Morcar. After some bargaining, Edward was grudgingly forced to accept this, as there was little appetite for a civil war. \n\nWilliam the Conqueror famously 'harried' the North, which obviously caused some resentment to say the least. \n\nNorthumbria continued to be a problem for William for years after the initial invasion in 1066 with at least one of Williams local lords being murdered there.\n\nHere is what I believe to be a source: _URL_0_\n\n(I am new to AskHistorians so please tell me if I have broken any rules or if this post is bad in some way. Thanks)"
]
}
|
[] |
[] |
[
[
"http://en.wikisource.org/wiki/Comin,_Robert_de_(DNB00)"
]
] |
|
w7ke4
|
What was the effect of marijuana on the ancient world?
|
did any other cultures criminalize it? did it help with scientific advancements? i never hear about weed in school other than health class and wonder if Historians can give some more context to its impact.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/w7ke4/what_was_the_effect_of_marijuana_on_the_ancient/
|
{
"a_id": [
"c5bav61"
],
"score": [
3
],
"text": [
"I don't actually know if they criminalised the drug or not, but the origin of our word cannabis is from the Akkadian word *qunubu*, meaning that in the Near East at least they had been aware of cannabis for a very long time. At least in a religious ritual context, it's clear that the Assyrians and Babylonians used cannabis, but it is entirely possible that it was *only* used in this context and there is no evidence for common household useage. You can detect chemical traces of drugs with modern archaeology, we've used it to detect opiate traces in a few containers (the ones i'm familiar with are from Bronze Age Cyprus).\n\nI'll be honest- of all the drugs that can be seen throughout history (rather than just the last 100-200 years) Cannabis does not seem to have made a big impact anywhere. Hemp was used as a material for weaving and clothing, so it was certainly useful to people. But off the top of my head, Opium certainly had more impact. It doesn't really seem to have been any more important than many other herbs and plants, and was certainly less important than grain, barley, olive trees, opium and salt in history to name a few natural products off the top of my head.\n\nI am less familiar with its recent history, i.e the Industrial Revolution and onwards, and someone familiar with that area may give you a different answer."
]
}
|
[] |
[] |
[
[]
] |
|
41ay9v
|
herding dogs. how do they know where the livestock needs to go? how much is instinct, and how much is training?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/41ay9v/eli5_herding_dogs_how_do_they_know_where_the/
|
{
"a_id": [
"cz0yyim"
],
"score": [
6
],
"text": [
"Where to take the animal is training, whatever method they use to do it is the genetics. Aussies will body block, nip heels, bark (very loud) and strafe. Other dogs like the Catahoula will be much more aggressive with the nipping, and I think Healers to some degree. A herding (or stock) dog will direct, a shepherd will protect. Great pyrinese is a good example of a protector. All these fit into what is known as pastoral dog breeds. \n\nA nickname for the Aussie is \"Velcro Dog.\" Get one and find out why. They're great with kids. I have a 9 mo female who warned a friend with get mouth for playing too rough with the kids."
]
}
|
[] |
[] |
[
[]
] |
||
245kwq
|
why is the us media overly sexualized, but then people are shamed for sexualization?
|
I guess it's kind of a complicated question to ask in the title. But it is a subject which has always confused me.
The FCC is so sensitive about some things (language, no nudity) on television/in media, but yet, the media still finds a way around that. We have scantily clad, thin, unrealistic women who are sexualized. Men are strong and physically fit.
I guess what I don't understand is, why is there such restraint over sexuality when it is blatantly obvious that people find ways around it? People are shamed for having promiscuous sex. Teens (especially girls) are also shamed if they have sex, and somebody's solution was an abstinence only program? Why are these things shamed if it is a natural part of humanity?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/245kwq/eli5_why_is_the_us_media_overly_sexualized_but/
|
{
"a_id": [
"ch3top8",
"ch3tpii"
],
"score": [
4,
14
],
"text": [
"What sells and what's \"taboo\" are often the same thing.\n\nDisease makes medicine sell.\n\nJoker makes Batman.\n\nIt's the oppositional defiance complex of humanity being used as a tool. If someone says \"you can't have that,\" but another says \"here's all of it\" you're going to go take it all. When those people are the voice of both sides, profits are reaped.\n\nIt sounds somewhat conspiratorial, but it's not. The FCC may not be in the pocket of tits and ass, literally, but, the tits and ass allow it to exist.\n\nThe way capitalisation works perpetuates these things. As long as a cow is breathing, take as much milk as you can.",
" > The FCC is so sensitive about some things (language, no nudity) on television/in media, but yet, the media still finds a way around that. \n\n...\n\n > why is there such restraint over sexuality when it is blatantly obvious that people find ways around it? \n\nYour question has a built-in presumption that the FCC is tightly regulating these things and that TV stations / content producers are actively trying to find loop-holes / ways to exploit these tight restrictions and get around them. In reality it's pretty much the exact opposite. \n\nFirstly, the FCC doesn't regulate Cable/Satellite TV stations, only freely accessible broadcast stations (the ones you can pick-up with an antenna). Secondly, even for the broadcast stations which are regulated by the FCC, there is nothing stopping them from broadcasting explicit language, nudity and sex at night time. The FCC regulates content during the daytime strictly for the protection of young children. At night, the safe harbor kicks-in at about 10 PM and any TV station (including broadcast stations like ABC, CBS, NBC, FOX, etc.) are all free to air highly explicit language, nudity, sex, etc.\n\nThe fact is these stations choose not to air such content and impose voluntary censorship. It's not the case that they're trying to push the boundaries as far as the rules will let them - quite the opposite... They are actually imposing rules of self-censorship upon themselves which are much more strict than any government regulations require.\n\nThis is mostly because they want to appease advertisers (many of whom don't like to be associated with Risqué content or anything which could be controversial). Self-censorship is also imposed to avoid public outcry from vocal parent/family and religious groups who may take offense to (what they see as) inappropriate content like explicit language, nudity, sex, and these groups have been known to organize boycotts. So basically TV stations electively choose to be uptight when it comes to things like sexuality because they're afraid of upsetting the people (e.g. advertisers) that help fund their stations.\n\nYou will notice that premium channels like HBO (which rely on subscriber fees rather than advertising) have no problems showing explicit language, nudity and sex on their channel."
]
}
|
[] |
[] |
[
[],
[]
] |
|
9gr1za
|
why does jello pudding mix only work with dairy milk?
|
Welll i recently tried to make it with coconut milk then almond milk. Those non dairy milks seem to hold a colloid gel thingie for a while and go all lumpyyy and liquidy as they sit in the fridge for longer ! Also chocolate fudge seems to hold better versus butterscotch/banana vanilla when made with non dairy milk! Why is thattt im baffled!
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9gr1za/eli5_why_does_jello_pudding_mix_only_work_with/
|
{
"a_id": [
"e669de8"
],
"score": [
4
],
"text": [
"They make ones that will work with non dairy milks. The proteins and fats and sugars in milk are pretty unique which is why they can make cheese. You cant make almond cheese or coconut cheese, and you cant make dairy pudding with them either. Maybe someone can explain the science behind the interactions with the casein(or whatever milk enzyme it is) that makes it work specifically"
]
}
|
[] |
[] |
[
[]
] |
|
1kffht
|
When did owning swimming pools become fashionable?
|
In other words...
When did owning pools specifically for swimming at your home become a popular thing to spend your money on?
Did the Romans go pool hopping? Did Charlemagne go skinny dipping in the backyard? Did one throw pool parties in one's manicured English garden?
Thanks!
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1kffht/when_did_owning_swimming_pools_become_fashionable/
|
{
"a_id": [
"cbotx8w"
],
"score": [
3
],
"text": [
"In Rome and Greece, swimming was part of the education of elementary age boys and the Romans built the first swimming pools (separate from bathing pools). The first heated swimming pool was built by Gaius Maecenas of Rome in the first century BC. Gaius Maecenas was a rich Roman lord and considered one of the first patron of arts - he supported the famous poets Horace, Virgil, and Propertius, making it possible for them to live and write without fear of poverty. However, swimming pools did not became popular until the middle of the 19th century. By 1837, six indoor pools with diving boards were built in London, England. After the modern Olympic Games began in 1896 and swimming races were among the original events, the popularity of swimming pools began to spread."
]
}
|
[] |
[] |
[
[]
] |
|
3qrkg3
|
What happens to disease immunity from vaccinations if you're HIV positive?
|
I'm wondering what happens when you've been vaccinated against a disease if you're HIV positive. Does the vaccine no longer have the effect of immunizing you against the disease in question due to the (presumably) low CD4 cell count? Or can the body still produce antibodies to combat the illness? Does it matter if you're vaccinated before or after HIV infection?
|
askscience
|
https://www.reddit.com/r/askscience/comments/3qrkg3/what_happens_to_disease_immunity_from/
|
{
"a_id": [
"cwjeia7"
],
"score": [
2
],
"text": [
"The body does still produce an effect but it is significantly reduced with a low CD4 count. Think of T helper (CD4) cells as basically the [bugles](_URL_1_) calling in the cavalry of the immune system; once an antigen presenting cell (APC) hands them some info and gives the T helper the secret handshake, they rally and direct the immune system. Without these you'll only really see a local response which isn't great for memory. Someone with a low CD4 count has to be very careful of live, attenuated (weakened) vaccines like influenza, smallpox, or [BCG](_URL_0_) because they can quickly develop an infection and die. Before obviously would be ideal for vaccination, afterwards (like most other infectious disease treatment with HIV+) has to wait until the HIV is under control."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/BCG_vaccine",
"https://en.wikipedia.org/wiki/Bugle"
]
] |
|
9aesjb
|
is there a difference between a racist and a bigot, and if so, what is it?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9aesjb/eli5_is_there_a_difference_between_a_racist_and_a/
|
{
"a_id": [
"e4uvh26"
],
"score": [
10
],
"text": [
"A racist is intolerant towards people of other races. A bigot is intolerant of other people's opinions. But bigot can sometimes be someone who's prejudiced because of another person's identity (be it their sexuality, class, gender, disability, etc)."
]
}
|
[] |
[] |
[
[]
] |
||
eytby
|
Questions about aspirin...
|
So I'm reading up on aspirin for a chemistry course dealing with organic compounds, and I don't really understand how to answer these two questions so hopefully I can get some insight here:
> 1\. What's a good substance that could be used as a solvent to dissolve aspirin?
You guys know, I'm sure, about the general rule of thumb that "like dissolves like." However, I'm not really sure what's *like* aspirin. Aspirin is non-polar because of the benzene group right? So would any non-polar solvent work then? What's the best solvent here?
> 2\. Use your knowledge of acids and bases to explain why old aspirin smells like vinegar.
So I Googled this a bit, and I know that aspirin is the acetate ester of salicylic acid and acetic anhydride. Essentially, this results in aspirin and acetic acid. After a while with the aspirin getting old and all, moisture gets involved and a sort of reverse reaction takes place where the H2O in the moisture reacts with the aspirin and you get salicylic acid and acetic acid -- which is a component of vinegar.
So I got that, but how do I use my knowledge of acids and bases to explain this? Is there a base involved here? Is this a reverse neutralization reaction or something?
|
askscience
|
http://www.reddit.com/r/askscience/comments/eytby/questions_about_aspirin/
|
{
"a_id": [
"c1c04c9"
],
"score": [
6
],
"text": [
"1. I synthesized aspirin in my undergraduate organic chemistry class. We dissolved it in 100% ethanol, then added water for recrystallization. The aspirin dissolves completely in EtOH, but is not as soluble in the water/EtOH solution. So, I would go with ethanol. Edit: [this paper](_URL_0_) describes solubility of aspirin in various solvents. Acetone seemed to work the best. \n\n2. I haven't looked at the thermodynamics of the reverse reaction, but it seems as though the acetyl group in aspirin would fall off and give you acetate/acetic acid. Edit: OK, I think I have it. A base would attack the carbonyl present in aspirin, leaving salicylic acid and acetate/acetic acid."
]
}
|
[] |
[] |
[
[
"http://pubs.acs.org/doi/abs/10.1021/je7005693"
]
] |
|
1bnb9k
|
what is today's news on google forking webkit and launching blink mean?
|
I'm not technical, but love to keep up with the latest tech news. Was reading about Google forking Webkit and launching blink, but don't really understand what just happened.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1bnb9k/eli5what_is_todays_news_on_google_forking_webkit/
|
{
"a_id": [
"c988cv0",
"c98mg2y"
],
"score": [
2,
2
],
"text": [
"Webkit is a web page rendering engine that Google chrome has been using for a while now because its lightweight and fast. Its also used in other browsers and is open source, meaning everyone can see how it works and more easily find flaws with it. Because its open its used in many other browsers on many different platforms and Google wanted to make it more tightly integrate with the rest of Google chrome. So basically chrome will soon use a tweaked version of webkit they're calling Blink. Forking means they basically copied web kit, renamed it and took control over the development so they could have the freedom of modifying it however they'd like.\n\nSo in short, Blink will make Google Chrome faster than it already is.",
"forking means creating a new code repository from the existing code base, but then switching your main code branch to the new one and deliberately not merging it back in to the previous code. \n\ngoogle chose to do this because they want to be able to make changes to the engine powering the Chrome browser without having make sure they're not breaking things for other people who were also using the code. \n\nthe code on google's fork will still be open source, but it will be developed independently of webkit from now on."
]
}
|
[] |
[] |
[
[],
[]
] |
|
25f887
|
If I were to accelerate a pebble to 99% the speed of light aimed at the center of the earth....what would happen?
|
So basically, does an object, even one as tiny as pebble make boom when moving that fast?
|
askscience
|
http://www.reddit.com/r/askscience/comments/25f887/if_i_were_to_accelerate_a_pebble_to_99_the_speed/
|
{
"a_id": [
"chglir2"
],
"score": [
3
],
"text": [
"A 10g pebble moving at 99% of the speed of light, hitting a solid surface, would release about 5.5*10^15 J of energy. This is similar to the energy of a 1-megaton nuclear bomb (by comparison, the Little Boy was about 1.5% as much and the Tsar Bomba 5000% as much)."
]
}
|
[] |
[] |
[
[]
] |
|
1b1l9o
|
amanda knox trial
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1b1l9o/eli5_amanda_knox_trial/
|
{
"a_id": [
"c92qmjg",
"c92sdyo",
"c92uz7i",
"c92wqhv"
],
"score": [
22,
44,
45,
4
],
"text": [
"From what I know:\n\nAmanda Knox, an American, was charged with killing her British roommate while in Italy.\n\nShe was tried and acquitted (which means she was found not guilty, or the charges were dropped), and so came back home.\n\nWell, apparently the Italian courts found new evidence or didn't like that fact, so they overturned her acquittal, and now she has to go back.\n\nHowever, in the US, this is called Double Jeopardy, which is illegal. We'll see how it turns out =)\n\nIf someone that has more knowledge about whether or not the US would consider this is Double Jeopardy, please chime in. I'm also interested to know how the US could possibly try to handle this.",
"Just a friendly reminder: US news sources, when you are lucky, are slightly biased towards AK innocence, as it is the most *appealing* opinion to US readers. Many just ignore the facts and go straight to defining the trial a farce and say that the proofs are weary. That's not the case. You can disagree with the *interpretation* of the evidence, but remind that the judges are highly trained and that the international pressure is toward the acquittal of AK, not the opposite.",
"Since this is a dupe, I'll repost my comment from [here](_URL_0_):\n\n---\n\nAmanda Knox was an American studying in Italy. She lived with a British roommate, Meredith Kercher, and was dating an Italian man, Raffaele Sollecito. In November 2007, while Knox and Sollecito were out together, a man named Rudy Guede broke into Knox and Kercher's apartment and raped and murdered Kercher.\n\nGuede's guilt was thoroughly and irrefutably established by ample physical evidence. He protested that he had simply been burglarizing the apartment when someone else broke in and murdered Kercher. He later changed his story to some kind of bizarre sex game involving both Knox and Sollecito in which he himself was blameless.\n\nThe evidence against Knox and Sollecito is essentially nil. Prosecutors claimed to have found DNA evidence implicating them, but the alleged evidence was contaminated and mistreated, and to get any traces of DNA, the lab needed to perform experimental (and questionable) amplification procedures that they were not qualified for. There were also footprints that tested negative for blood, \"proving\" that someone had cleaned up the scene to conceal their involvement.\n\nIn addition to the \"physical\" evidence, the prosecution claimed that their conduct had been suspicious. You can google this if you want, but it's all inconsequential given that there was never any reason to suspect them to begin with. Much of it is ordinary character assassination – painting Knox as \"loose\" and a partier, that sort of thing, as though that were evidence of murder.\n\nAll three of them were convicted, Guede because he was clearly, unambiguously guilty and Knox and Sollecito because people are stupid and make stupid decisions when confronted with violent murder, sex, and international tensions. An appeals court overturned that verdict, largely citing a report pointing out that the alleged physical evidence was garbage. That court freed the two and ordered a new trial.\n\n---\n\nI did a bit more reading, to catch up with what's happened in the last couple of years. Addenda:\n\n- One of the \"suspicious\" things that Knox did was falsely implicate her boss. This occurred during an extended high-pressure interrogation during which Knox claims to have been mistreated. It turns out that the whole idea of her boss being involved was fed to her by the police based on their misunderstanding of the phrase \"see you later\" in a text message. Knox retracted the implication the next day. She was convicted of slander, and the appeals court did not overturn this, setting her sentence as three of the years she had already served.\n- Guede did change his story to implicate Knox and Sollecito after hearing that they were suspects, but the wild orgy-murder scenario was dreamed up by the prosecutor. Also, alleged Satanism. Yeah.\n- There will be another trial because the prosecution appealed. This is a thing that can happen in Italy. Knox will not return to stand trial, and it is unlikely that she would be extradited even if (somehow) found guilty.",
"The BBC has a really good [timeline of event](_URL_0_) here. It's relatively unbiased (compared to some of the comments on here) so I suggest anyone who wants a more neutral account of events check it out."
]
}
|
[] |
[] |
[
[],
[],
[
"http://www.reddit.com/r/explainlikeimfive/comments/1b1ftq/eli5the_amanda_knox_saga/c92qdh6"
],
[
"http://www.bbc.co.uk/news/uk-15000651"
]
] |
||
ek34xm
|
could australia use seawater to put out the fires, or is fresh water required, so as not to add a bunch of salt to the soil?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/ek34xm/eli5_could_australia_use_seawater_to_put_out_the/
|
{
"a_id": [
"fd57gbq"
],
"score": [
2
],
"text": [
"We could, but it would have the consequence you mentioned. Also, transporting water inland is a very expensive thing to do."
]
}
|
[] |
[] |
[
[]
] |
||
1jlh1v
|
what is an integrated circuit, what does it do, and how does it do it?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1jlh1v/eli5_what_is_an_integrated_circuit_what_does_it/
|
{
"a_id": [
"cbfuqzb"
],
"score": [
2
],
"text": [
"An integrated circuit is another word for s silicon chip where many components (transistors, resistors) are *integrated* on the same chip. Prior to the invention of the integrated circuit, all the individual resistors, transistors, diodes, and capacitors had to be wired into and soldered onto a breadboard.\n\nThe advantage is it uses less electricity and less space and generates less waste heat. \n\nIt accomplishes what it does by layering silicon that has been alloyed with various substances to make conductive, semi conductive, and non conductive layers - as well as metal layers to carry electricity and perform other effects. Depending on which layers are exposed to the metal tracery, various effects happen, which create transistors, resistors, etcetera."
]
}
|
[] |
[] |
[
[]
] |
||
5ybraz
|
why do storage devices have capacities that are multiples of 8?
|
Strictly speaking about gigabytes (8GB, 16GB, 32GB etc.)
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5ybraz/eli5_why_do_storage_devices_have_capacities_that/
|
{
"a_id": [
"deor62k",
"deorzp6",
"deosl4x",
"deot0ck",
"deoufcb",
"depcpew"
],
"score": [
2,
2,
25,
45,
7,
2
],
"text": [
"Computers operate on a binary number system (0/1, on/off), and it was decided that 8 *bits* make up one *byte*.",
"Flash memory makers mass produce one chip that holds a certain capacity. This reduces cost for them as they only need to produce one chip. Lets say a Samsung factory makes 8GB chips, so in order to produce a larger drive, let's say a 16GB drive, they will array two chips into one board. Three chips and you get 24, and so on.",
"In fact, this is related to the powers of 2. Because computers use a binary language(0 or 1), the data is translated as a combination of different patterns with only these two options. Think like this: if you had a question, you would had only two possible answers, true or false(or on/off ), and you would need just one digit(bit) to answer it, which could be 0 or 1. That's 2^1. If you had two questions, and two possible answers for each one, that's 2 bits and four different representations(0/0, 0/1, 1/0, 1/1), 2^2. And the higher the information, the greater the power and so it goes...\n\nEDIT: Spelling.",
"storage is a collection of 1's and 0's (bits) and 8 bits form a byte. all the information about your files, programs and anything else is stored in this binary form. lets just call this the data. \n\nhowever just storing the data isn't enough. you have to be able to manage all this data, and how to find it all. that way when you open a file, the computer knows where to go to find all the data that comes together to form the file. this is done by giving each location on the storage device an address. and since there are SO many addresses, we actually need a way to label them all. which we do - in binary.\n\nand because of this, a storage device has a certain number of locations we are able to reference before we run out. and without getting technical about binary (with 8 bits you can address 2^8, or 256 locations), multiples of 8 means we are using every single available location to store data. \n\nso if we had a 16GB USB and wanted to make it bigger, to expand it to 20GB would be silly. since we are already making more locations available to reference, we might as well use every single location and expand it to 32GB.\n\n*thougt id add this in in case you do want to get technical:\nso like i said, 8 bits mean you can address 256 locations. if we add one more bit, we get 2^9 different locations available to us, or 512. this continues... 1024, 2048, 4096..... so you can see that with the addition of each bit we get a twice as many more locations to store the data. this is why you often see 512mb, 1GB, 2Gb, 4Gb, 8Gb etc... sizes for storage!",
"They don't always.\n\nDigital language is in powers of 2. 8 is a multiple of 2. Anything that is a multiple of 8 is also a multiple of 2.\n\nIf you want to specify a memory address in digital, you have to use the language which lends itself to powers of 2. Every digital storage device has a maximum addressable range that is a power of two, however, they need not consume that entire range.",
"I guess the real questions is why is a byte made up of 8 bits?\n\nWikipedia: The byte (/ˈbaɪt/) is a unit of digital information that most commonly consists of eight bits. **Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable unit of memory in many computer architectures.** The size of the byte has historically been hardware dependent and no definitive standards existed that mandated the size. The de facto standard of eight bits is a convenient power of two permitting the values 0 through 255 for one byte. The international standard IEC 80000-13 codified this common meaning. Many types of applications use information representable in eight or fewer bits and processor designers optimize for this common usage. The popularity of major commercial computing architectures has aided in the ubiquitous acceptance of the 8-bit size."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
|
35r2s0
|
how can a butcher "age" beef for a large period of time (21 days etc.) yet if you were to take the same cut of meat not aged and leave it in the fridge for a time after its expiry it would turn rancid and have to be thrown out?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/35r2s0/eli5_how_can_a_butcher_age_beef_for_a_large/
|
{
"a_id": [
"cr6zcbz",
"cr6zcyx",
"cr71kk7",
"cr7g2bq"
],
"score": [
19,
3,
8,
2
],
"text": [
"It has a lot to do with conditions and surface area.\n\nA butcher hangs meat in all one piece in a cold room, such as a full \"side\" of a cow, and that side of beef isn't touching anything besides the hook it hangs from, and generally is not handled while it hangs. No flies are allowed in the area thanks to multiple plastic sheet door protectors, bug lights and other means. So its exposure to germs is very much minimal, as is the surface area of meat that contacts the air. And the whole region's humidity, temperature, and other variables is really tightly controlled.\n\nWhen you take a steak or roast home, it's been de-packaged from the slaughterhouse, carved up, cut, and repackaged. All of this handling exposes it to germs and surfaces. Add to it all of your handling, the germs drifting around more freely in your house, and the already-advanced age of the fresh meat, and it'll go rancid a lot quicker.",
"They age it in a very cool fridge (that doesn't get the door opened several times a day, allowing warm air and pathogens to enter, in a large mass (so any spoilage happens on the surface) and remove the spoiled parts. ",
"There is dry aging and wet aging. Wet aging is when the cut is left in its vacuum sealed bag and aged in optimal refrigeration conditions. This is the simpler of the 2 and the most common. Dry aging is where the cut is allowed to aged in controlled conditions outside of its bag. This allows a mold to form on the outside of the cut. That shit is cut off before it is prepared. ",
"Actually [you can](_URL_0_) dry age at home in your fridge. I've done it a number of times. It's just about knowing the correct conditions to prevent bad organisms from growing and encouraging the good ones. Kinda like beer in a rough manner of speaking."
]
}
|
[] |
[] |
[
[],
[],
[],
[
"http://www.seriouseats.com/2013/01/the-food-lab-dry-age-beef-at-home.html"
]
] |
||
61zs5d
|
Why did Hitler declare war on the US?
|
I understand the alliance stuff, but Japan made a dumb move considering their lack of resources.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/61zs5d/why_did_hitler_declare_war_on_the_us/
|
{
"a_id": [
"dfikc0f"
],
"score": [
26
],
"text": [
"Modified from an [earlier answer of mine](_URL_0_)\n\nAlthough it was in many respects a foolish blunder in hindsight, there was a lot of strategic calculation that went into German declaration of war on the United States. Hitler and the Germans did not so much see the declaration of war as the start of a *quid quo pro* process with Japan leading to a Japanese invasion of Siberia, but rather an opportunity to gain time and militarily isolate the United States by giving German armed forces a free hand in the Atlantic and encourage the Japanese to keep fighting in the Pacific. \n\nBoth Hitler and German military planners were not on board with the bombing of Pearl Harbor itself mostly because they were completely ignorant of Japanese the scale and extent of Japanese planning. Although the Japanese occupation of French Indochina and the resulting US blockade of strategic raw materials made it apparent that war in the Pacific was imminent, German leaders were in the dark about future military operations. Two days before Pearl Harbor, the German Foreign Minister von Ribbentrop actually hoped that America would be the one to instigate military aggression against Japan. \n\nVon Ribbentrop's thoughts on the situation in the Pacific was emblematic of much of German geostrategic thought in the winter of 1941. The actions of the USN in the Battle of the Atlantic in which US ships jettisoned most pretensions of neutrality indicated that the US was readying to enter into the war. Although an expansion of the war carried with it new uncertainties, a number of German military planners mistakenly concluded that Japan's entry into the was in the Pacific was largely beneficial to Germany's strategic interests. \n\nPart of this miscalculation stemmed from the dire situation Germany had found itself in at the end of 1941. Although Barbarossa had achieved spectacular gains, the German invasion had not achieved the desired result of a complete collapse of the Soviets. The strengthening Soviet resistance and counterattacks was a bitter pill for the Germans to swallow. Moreover, the strengthening of the British military position in North Africa and the Atlantic seemed to threaten German-occupied Europe's southern and western flanks. German planners hoped that Japanese conquests in East Asia and the Central Pacific would rectify this global strategic balance by forcing both the British and Americans to reorient their military resources to the Pacific. An OKW strategic assessment produced on 14 December outlined their expectations for the British response: \n\n > Securing her position in the Middle East has gained even greater importance for Britain since Japan's entry into the war-not only because of the Persian and Mesopotamian oil, on which the British navy in the Indian Ocean must depend once the oil wells of Borneo and Sumatra are lost to it, but also because of the especially important maintenance of sea communications through the Suez Canal and because of the air communications, based upon this region, between the mother country and India, East Asia, and Australia. Execution of this strategic task will no doubt be seen by Britain to be just as vital as the maintenance of her Indian-Malayan position, which is crucial for the safeguarding of India, Australia, and New Zealand. \n\nIn OKW's estimation, the Japanese conquest of SE Asian rubber, tin, and oil sources would deprive the British and Americans, and by extension the Soviets, of this strategic war material. The *Kriegsmarine*, facing its first serious reversals in the Battle of the Atlantic and Mediterranean, welcomed the thought that both the RN and USN meeting the Japanese naval challenge would give German and Italian naval forces time to regroup. The declaration of war gave the *Kriegsmarine* a free hand to attack American shipping without as much interference from the USN and RN. According to the Naval Staff's estimation, expanding the war would divide Allied naval power, which prior to Pearl Harbor was in seeming danger of uniting. \n\nUnderlying this German enthusiasm for Japanese belligerence was the hope that the Japanese would present enough of a strategic diversion to allow German military forces to complete the job in the USSR they had begun the previous June. The defeat of the USSR remained the main strategic priority for Germany military planning. Only the *Kriegsmarine* evinced any great interest for a grand military hookup with the Japanese in India. Although both the Navy and von Ribbentrop urged Hitler to agree to a joint Axis declaration on India, the German leader refused on the grounds that such an anticolonial measure was not in the strategic interests of Germany. Hitler held out hopes that an anti-Churchill faction would come to the fore once Stalin had been beaten and threatening India would supposedly undercut support for a separate peace. OKW began in 1942 tentative plans for a wider invasion of the Middle East, but only after the success of Blue's offensive in the Caucasus. \n\nHitler's declaration of war on America gave German military much greater latitude to plan for a western defensive barrier. Expanding the war would also cow the various neutrals on Germany's flanks (Turkey, Spain, and Sweden) to accede to German demands. German entry into the war on Japan's side would also prevent the latter from making a separate peace prematurely. Although Hitler's government did not want to give sanction to Japan's anticolonial pretext for the war, it was sympathetic to Tokyo's request on 2 December for the Axis partners to never hold a separate peace, which culminated in the 11 December declaration for no separate peace. This was in keeping with the Third Reich's strategic thinking with regards to the Anglo-American powers in that it was in German interests to keep them preoccupied outside of areas controlled by Germany. So long as Japan was stiffened up to resist the Anglo-Americans, Germany strategic interests would be secured. OKW's 14 December report claimed the prognosis for the following year good for these four reasons:\n\n > I) Within the period left to it before the full mobilization of the American war machine, Germany would reach its military objectives in the east, in the Mediterranean, and in the Atlantic.\n\n > II) Germany would succeed, by political means, not only in inducing its allies to intensify their war efforts, but also in securing the periphery by bringing the flanking powers-hitherto neutral-of Turkey, Spain, Portugal, and Sweden into the continental defensive bloc.\n\n > III) The Japanese offensive would have enough endurance and momentum to tie down a substantial part of the Anglo-American potential in the Pacific for a considerable time. \n \n > IV) Under these circumstances the United States would not be able to conduct an offensive two-ocean war in the foreseeable future.\n\nThe experience of 1942 would prove each of these suppositions unduly optimistic. In short, the Germans believed that they possessed both the time and the resources to meet the new strategic challenge. They fundamentally underestimated America's industrial capabilities and overestimated the ability of Japan to act as a sink for Anglo-American resources. Even more fatally, both Hitler and OKW overestimated both Germany's own ability to deliver a fatal blow in Operation Blue and their chances of securing their strategic flanks with secondary forces like DAK and the *Kriegsmarine*. \n\nThere was also a domestic component to Hitler's decision to declare war. One of the central mythologies at the center of National Socialism was that Germany was at the cusp of a victory in 1918 until stabbed in the back by the \"November Criminals.\" While much of the public invective of the NSDAP was directed at the Judeo-Bolshevik instigators of the November Revolution, there was a considerable concern behind the scenes that the German civilian population were duped into following peace. In this schema, Wilson's promise of an honest peace proved to be a siren call for the German public that had suffered greatly during the war. Consequently, the Third Reich devoted considerable resources to mollify domestic public opinion during the opening stages of the war. Goebbels's diary entries consistently noted an acute attention to German public opinion and disgruntlement. By taking the initiative out of the US's hands and declaring war on them, the declaration of war was being proactive by preventing another iteration of the 14 Points. Hitler's public declaration at the Reichstag went to great lengths to highlight America's Rainbow Plans and the pre-existing belligerency of the US in the Battle of the Atlantic. Hitler's speech troweled on a great deal of antisemitism as well, differentiating a strong Europe from an allegedly Jewish global conspiracy that stretched from Moscow, to London, and Washington. By painting the US as a self-interested power in thrall to Jews, Hitler was cutting off a possible redux of 1918 where America's offer of a geopolitical moral alternative ate away at German civilian support for the conflict. \n\n"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/3i6lg0/was_germany_onboard_with_the_japanese_plan_to/"
]
] |
|
2dk7wd
|
What was Damascus steel?
|
I would like to know more about Damascus steel and have found two very different explanations for what it was. The first is that it was a form of pattern welding. The other is that it was a crucible steel. What actually was it?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2dk7wd/what_was_damascus_steel/
|
{
"a_id": [
"cjqhi92",
"cjqln4i"
],
"score": [
89,
23
],
"text": [
"Truthfully, we are still trying to understand the process of Damascus steel! We still don't know how the ancients did it.\n\nIt's widely believed to be the process of tempering steel to make it stronger, studies have shown Damascus steel to contains nano-fibres which greatly increased it's strength and durability compared to other metals of the time.\n\nHowever we've only recently been able to duplicate the steel with modern techniques, as said we don't know how the it was actually done. And only in modern times have we had the technology to see and know that nano-fibres were the reason that made it stronger.",
"It was both!\n\nThere's two types of steel called Damascus steel, you can't see a difference with your naked eye.\n\n The first (pattern welding) is a folded steel, with two initial layers of high and low carbon steel. This is not actually remarkable other than its appearance compared to other steels of the time.\n\nThe second, which the legends come from (its not up to that level, but the stuff *is* unique), is a crucible steel. With and low carbon steel that contain one of vanadium, molybdenum or a third I forget. Very very small amounts of these elements are needed, around 100 parts per million, the technique was likely lost because the iron mine the crucible version was being made of was shut down, and it was actually budget concerns that led the metallurgist who discovered this to use an ore with appropriate impurities, he knew they were in the wootz damascus steel but thought them too trace to be significant.\n\nSource: \nThe key role of impurities in ancient damascus steel blades J. D. Verhoeven, A. H. Pendray, W. E. Dauksch \n\n_URL_0_"
]
}
|
[] |
[] |
[
[],
[
"http://www.tms.org/pubs/journals/JOM/9809/Verhoeven-9809.html?ref=Klasistanbul.Com"
]
] |
|
ryiub
|
How Did DNA Evolve?
|
If evolution is the change in heritable characteristics over time (changes to DNA), then how did DNA evolve to become so complex as it is now?
|
askscience
|
http://www.reddit.com/r/askscience/comments/ryiub/how_did_dna_evolve/
|
{
"a_id": [
"c49oq3u",
"c49qn8i",
"c49qrb0"
],
"score": [
2,
3,
3
],
"text": [
"What do you mean by **complex**? What would you like to know about DNA?",
"Based on your previous comments, it sounds like your main question is something like \"how did DNA evolve in the first place when we now know that many different proteins are required for its function and propagation?\"\n\nIf that's an accurate representation, I would point you to the [RNA world hypothesis](_URL_0_). This is the idea that RNA, not DNA, was actually the first nucleic acid polymer to arise. The RNA is more satisfying as a starting material than DNA is because we know that RNA has the capacity to perform some limited catalytic functions. For instance, RNA is a major component of ribosomal structure and function and I'm not talking about mRNAs or tRNAs. \n\nBasically, it is hypothesized that initial RNA molecules were simple replicating machines that didn't really encode anything. The RNA was simply structured to provide catalytic activity to generate a copy of other RNA molecules it came across that had similar catalytic activity. Overtime, changes in RNA structure lead to different types of catalytic activity until a relationship between nucleic acids and amino acids could be formed. ",
"I see that the RNA world hypothesis has already been raised. That's probably the easiest way to imagine things coming about. See [this](_URL_0_) -- in not too much time, scientists have made significant strides in putting together a much more cohesive picture in how these self-replicating RNAs may have been built.\n\nIn terms of how *DNA* got more complex, well, every time a cell replicates its own DNA, it makes mistakes. That is one of the bases of mutation, which drives evolution. The DNA sequence of the cell is a record of perhaps a billion years of imperfect replication. There's remnants of all kinds of things in there -- gene duplications, deletions, insertions by viral infections. There are pseudogenes (husks of dead genes), there are franken-genes consisting of a few genes spliced together, there are sometimes 20 copies of very similar genes in a row. That's genomics for you and a reason why there's a whole subset of biology devoted to it..."
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/RNA_world_hypothesis"
],
[
"http://www.sciencedaily.com/releases/2009/01/090109173205.htm"
]
] |
|
1qmku1
|
why don't baseball pitchers wear a protective helmet if a line drive could cause permanent brain damage among other things?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1qmku1/eli5_why_dont_baseball_pitchers_wear_a_protective/
|
{
"a_id": [
"cdeau33"
],
"score": [
10
],
"text": [
"Simply put, pitchers don't want to wear them. It's as simple as that. As far as I know, it's perfectly legal for players to wear helmets in the field and it has been done before (by first baseman John Olerud).\n\nHere are the reasons I've read about that account for the resistance to pitchers' helmets:\n\n1) While the effects of getting hit can be bad, it's not a frequent occurrence.\n\n2) Batters keep their heads steady as they swing. Pitching motions can be violent and shaky. As a result, helmets are likely to fall off or cover a pitcher's eyes.\n\n3) Fear that wearing a heavier object on one's head can affect the pitcher's mechanics (throwing motion). \n\n4) Concern that helmets would be hot, sweaty, and generally uncomfortable. \n\n5) Appearance. Right now, while pitchers almost universally wear hats, violating the trend could be embarrassing or make the pitcher less able to intimidate batters.\n\n6) A lack of knowledge/publicity surrounding devices designed specifically for pitchers. \n\n7) Tradition. Baseball has an unusually prominent focus on remaining traditional with the way things work on the field. That's not to say that big changes don't happen, but when they do, there's often resistance. "
]
}
|
[] |
[] |
[
[]
] |
||
7gtwim
|
How do we know the electron is a fundamental particle and not composed of something smaller?
|
askscience
|
https://www.reddit.com/r/askscience/comments/7gtwim/how_do_we_know_the_electron_is_a_fundamental/
|
{
"a_id": [
"dqlp9lo",
"dqlrt5h",
"dqltmre",
"dqlznxt"
],
"score": [
56,
17,
5,
10
],
"text": [
"Theories that suggest a composite electron just aren't as effective or accurate as the ones that assume it to be an elementary particle (Namely the [standard model](_URL_0_)).\n\nFurthermore, high-energy scattering experiments have revealed that it has a very tiny, nearly spherical charge distribution while also being very lightweight. That's hard to accomplish with a composite electron.",
"The short answer is \"We don't\" but there's so far zero evidence suggesting that they are (and there have been many attempts to check if electrons have finer structure). Thus we continue with the theory that matches experiments AND has the least complexity. Complexity that has no predictive power serves no purpose (Occum's razor and all that).",
"Scattering experiments have shown that if it has any size, it has to be really, really tiny, on the order of 10^-18 m. Now you could say that maybe its constituent particles are even tinier, but that seems unlikely for another reason. Due to the Heisenberg uncertainty principle, the product of the uncertainty on the position and the moment has to be larger than a certain constant. So if you confine some hypothetical particles in a space as small as experiments show the electron, their momenta need to be enormous to fulfill the principle. Momentum means energy, in fact, much more energy than the electron's mass is equivalent to.\n\nThis, together with [other considerations that show that the constituent particles need to be a million times heavier than the electron itself](_URL_0_) imply that any hypothetical interaction keeping the electron together would need to release this difference as binding energy. That isn't unusual, in fact a helium atom weighs about 3% less than its parts. However, it would have to release a massive amount of binding energy, which would also have to be fine-tuned very precisely to leave behind a millionth to a billionth of the constituent mass-energy. Such fine-tuning seems very unlikely.",
"Most of the other answers are correct but perhaps a bit unsatisfying.\n\nI'd like to answer the question a little more broadly.\n\nConsider: **How do we define a fundamental particle?**\n\nAs discussed in Weinberg's \"The Quantum Theory of Fields\", a good definition of a fundamental particle is one which has no **continuous** degrees of freedom other than the momentum. That is, each particle should be uniquely describable with just its energy, momentum, and perhaps spin or helicity -- given two particles which have the exact same values of these variables, they should behave exactly identically in any conceivable experiment. However, within the theory, it is quite conceivable that there is some continuous degree of freedom which is accessible only at high energies; so the particles would not be fundamental if such energies are achievable in your experiment.\n\nThis is an important point, so I'll state it again: **it is most useful to think of \"fundamentalness\" as a function of energy.**\n\nIn the Standard Model of particle physics, photons and electrons have no structure at any energy. In addition, protons have no (accessible) structure until an energy of several GeV. So for most ordinary low-energy protons, it is perfectly reasonable to give their energy, momentum, and spin, and they can be considered fundamental particles at \"low\" energies (which includes all energies accessible outside nuclear experiments, including specifically all life and chemistry processes). Indeed for several decades after the discovery of the proton, it was regarded to be as fundamental as the electron.\n\nProton structure is accessible at higher energies -- if an electron is shot at a proton at several GeV, it can [\"probe\"](_URL_1_) the internal structure; at such energies, if you want to explain the experimental results, the only way out is to introduce the notion that a proton is composed of quarks with fractional charge, and that the electron is really interacting with these quarks. There are many different continuous degrees of freedom here: one of them, for instance, is the fraction of the total proton energy that is occupied by any one quark -- this is the intuitive meaning of [parton distribution functions](_URL_0_).\n\nBack to the original question -- there have been a few experiments that try to experimentally find some kind of internal structure. Generally, all such experiments involve extremely fine measurements of electrons at ever higher energies. But we have found no evidence of this so far.\n\nIn short, the theory states that there is no structure in an electron at any energy. Experimentally, this theory has been well-tested until extremely high energies. So for all purposes, we say that electrons are \"fundamental\", and we don't need to qualify the statement by adding \"at energies less than X GeV\" like we need to do with protons."
]
}
|
[] |
[] |
[
[
"https://en.m.wikipedia.org/wiki/Standard_Model"
],
[],
[
"http://gabrielse.physics.harvard.edu/gabrielse/overviews/ElectronSubstructure/ElectronSubstructure.html"
],
[
"https://en.wikipedia.org/wiki/Parton_\\(particle_physics\\)#Parton_distribution_functions",
"https://en.wikipedia.org/wiki/Deep_inelastic_scattering"
]
] |
||
2e1s3j
|
when having diarrhea, why is it i can sit there for 20-30 minutes after going and nothing comes out. but when i get up, i immediately have to go again?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2e1s3j/eli5_when_having_diarrhea_why_is_it_i_can_sit/
|
{
"a_id": [
"cjv8qo9",
"cjvhj0w",
"cjvi416",
"cjvihs9",
"cjvilc5",
"cjvj2zo",
"cjw2dvd"
],
"score": [
135,
10,
63,
2,
3,
15,
2
],
"text": [
"You can get the sensation of excrement entering your anus without it actually being there. You technically feel like you have to go even while sitting down but that's only because you're actually contracting your \"poo muscles.\" When your body doesn't feel itself trying to \"go\" any more, it tells your brain \"hey, dude there's something big coming down\" and then you instinctively contract again, repeat until you actually poo.",
"I would assume that it's because while seated on the toilet you have expelled everything that is possible whilst in that particular position, but when you move you are changing the physics sufficiently to release more.\n\nOr in pure ELI5 language; you hadn't finished yet, but your tummy thought you had as you hadn't moved in a while. \n\nAbsolutely not sure on this though, I'm not a fucking explosive shit doctor.",
"Poo waits further up your bum.\n\nIt only moves down into the last part of your bum when the top part is full. When poo is in the bottom part, it makes you feel like you have to go. \n\nWhile you are sitting there, the bottom part is empty but the top part is filling up with diarrhea again. \n\nBecause of the angle, it doesn't flow down into the bottom part. When you stand up (and because it is liquid) it all pours down into the bottom part and you have to go again.",
"When you sit down and lean forward slightly, you are actually decreasing the pressure on your abdominal cavity. This is why when you have a stomach ache or cramping you instinctively hunch over. When you stand up and start moving around, there is increased pressure on the abdominal cavity, and then you start feeling like you have to go again. ",
"I don't see the rock-back-and-forth comment.\n\nrock back and forth about 10 times before getting up. You'll get the standing up sensation without standing up.",
"the end of your intestines have two sets of muscles, one inner and one outer (the one that you can see), one or the other always stays closed to prevent you from seeping all day long, so when your anus is closed and you're not pooping the inner muscles relaxes allowing poop to enter your colon, once its full your body will tell you its time to go, you'll open your anus and the inner muscles Closes off your colon so you can empty it out.\n\nwhat happens with diahrea is that the liquid that goes with the poop will seep through the inner muscles and give you a constant feeling of having to go. so once you're sitting on the toilet, you'll subconciously keep \"pushing\"...but as long as your anus is relaxed, your inner muscle is closed, and you wont be able to evacuate, the pressure you apply with your stommach muscles will instead pile up the poop on the inside of the muscle in your intestines.\n\nThe moment you get up you close your anus and the inner muscles relaxes, and the piled-up-poop will immidiately fill your colon Again and you'll have to hit the shitter right away.\n\na good way to help it along is to tilt sideways lifting a butt cheek off the crapper, this makes it harder for the inner muscle to stay contracted and it'll be easier to squeeze out.",
"I remember once in college a student explaining why the Chinese culture squatted like that to go, he said it better line you up to go."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[]
] |
||
4yvsck
|
Do insects, particularly cockroaches, use acid in their digestive system?
|
From what I can gather, they seem to use gizzard to grind food, and break them down with enzymes in their midgut. Is there no acid involved like larger animals do?
|
askscience
|
https://www.reddit.com/r/askscience/comments/4yvsck/do_insects_particularly_cockroaches_use_acid_in/
|
{
"a_id": [
"d6riryn"
],
"score": [
9
],
"text": [
"It really depends on the insect. Mosquitoes, black flies and some lepidopterans actually have a basic stomach pH.\n\nHowever I did find a study on cockroaches that suggested that they seem to have an acidic stomach pH from around 6-2.\n\nIf you're interested here is the link\n\n_URL_0_"
]
}
|
[] |
[] |
[
[
"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1251983/pdf/biochemj01143-0037.pdf"
]
] |
|
42okwp
|
How legitimate are China's claims in the South China Sea?
|
[deleted]
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/42okwp/how_legitimate_are_chinas_claims_in_the_south/
|
{
"a_id": [
"czcdxks"
],
"score": [
20
],
"text": [
"Disclaimer: I am a Filipino poster, but I am of Chinese ethnicity. I'm just calling it as I see it based on my knowledge of international law.\n\nIf we're going to go by the Nine-Dash Claim then quite frankly the claims are a whole bunch of nonsense.\n\nFirst of all, territorial waters are only supposed to extend 12 nautical miles from a nation's coast line. To claim the South China Sea would require China to massively increase this internationally agreed limit. Even using the Exclusive Economic Zone definition - which extends 200 nautical miles from the coast, simply isn't enough to cover the South China Sea. At this point China's attempt to claim the entire sea already falls apart. Here is a map showing the Exclusive Economic Zone limits versus China's claim to the entire South China Sea:\n\n_URL_0_\n\nHowever, some \"geniuses\" in China claim to have unearthed ancient documents that \"prove\" that the South China Sea was always Chinese along with the Spratley Islands. The problem is that these map actually date only from 1947, published by the Republic of China (Taiwan). Additionally, the Nine-Dash line is reliant on using reefs as the basis for extending territorial waters; which isn't recognized by international law.\n\nUnfortunately certain Chinese officials were apparently undeterred by the legal impossibilities, and instead had the reefs expanded using concrete until they could be considered real \"islands\" that could be considered for the purpose of counting territorial waters. This was why there was all this recent concern about Chinese construction in the South China Sea.\n\nAt this point the Philippines decided to literally take the Chinese to court at the UNCLOS (United Nation Convention on the Laws of the Seas) to stop the Chinese plans. And the Philippine team, to a lot of people's surprise, are actually winning the case handily at this point; by focusing on the \"ownership\" of a number of reefs in the Spratleys (e.g. Scarborough).\n\nTo elaborate, the Philippine government showed the records of several ships which were wrecked on these reefs in the late 1800s - and how _all_ of them chose _Manila_ (capital of the Philippines) as the court of arbitration when it came to resolving the insurance claim. These records were verified by neutral third parties (e.g. Lloyd's of London, which handled the insurance claims).\n\nHence, the Philippine government had _demonstrated_ that they they were already exercising legal jurisdiction over the disputed reefs since the late 1800s, or decades before the Nine-Dash Map was published. \n\nHad China really been serious about owning these reefs, then it should have filed complaints back in the 1800s protesting the arbitration in Manila courts. They never did, and thus by extension waived their own jurisdiction. And if you don't have jurisdiction over a piece of land, you certainly can't claim to have sovereignty over it.\n\nThis was why the general Chinese reaction to the hearings had been to snub it entirely and called for a return to negotiations. They knew they had been completely outfoxed on the legal front. That doesn't mean China is going to stop trying however; but it's certainly more cautious now as it does not want to be seen as breaking international law.\n\nEdit: Added a map."
]
}
|
[] |
[] |
[
[
"http://globalnation.inquirer.net/files/2014/03/South-China-Sea.jpg"
]
] |
|
56qt9e
|
why does holding hands with your so feel nice?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/56qt9e/eli5_why_does_holding_hands_with_your_so_feel_nice/
|
{
"a_id": [
"d8lm0ah"
],
"score": [
8
],
"text": [
"Because physical contact releases dopamine in your brain which is a feel good chemical. Lots of recreational drugs have a similar effects."
]
}
|
[] |
[] |
[
[]
] |
||
9czq7k
|
Why aren’t underwater windmills more of a thing?
|
The way I reckon it, the tides go through multiple times a day in a predictable way. If turbines just sat there collecting energy 24/7 we’d get a lot of energy. You could put a nearly infinite amount of them up and down the coast line.
edit: thanks for all the reply’s
|
askscience
|
https://www.reddit.com/r/askscience/comments/9czq7k/why_arent_underwater_windmills_more_of_a_thing/
|
{
"a_id": [
"e5ee2hr",
"e5eph5w",
"e5f4sqf",
"e5f9uhm"
],
"score": [
146,
35,
4,
6
],
"text": [
"A few reasons,\n\n1. Maintenance. It's very costly to maintain underwater infrastructure.\n2. Corrosion is a big problem in salt water environments. Meaning more maintenance is needed.\n3. Biological buildup. Again in saltwater, the blades are going to end up getting fouled by barnacles and other aquatic life making them less efficient over time... also needing more maintenance.\n4. Limited useful locations - Tides are predictable, but you need to be in a place like a narrow bay inlet where the water actually flows inland and Outland. Out along most places on the coast, there's not actually a lot of tidal flow, just rising water. An ideal sort of location might be under the golden gate bridge. These high flow areas tend to be murky... complicating maintenance. That useful water flow also complicates maintenance because you can't easily service in high flow times.\n5. Lastly transporting that power requires infrastructure either underwater or on the shore. In many of the ideal locations, placing that infrastructure is probably politically complicated.\n\nCompared to wind turbines, the extra cost makes tidal systems less efficient over time. That's not to say there are no ideal places for it. It's just there are very few compared good wind production areas\n\nHydroelectric is more or less the same sort of thing mechanically, but you end up harvesting the potential energy from falling water flowing downhill. Frequently hydro project serves other purposes like flood control, fresh water collection, habitat and recreation. These other factors offset some of the higher capital and maintenance costs. It's also something that can be controlled and called upon in a time of need whereas a tidal system would be more like solar where it is predictable, but not controllable. Wind is neither predictable or controllable.",
"I’ve installed underwater turbines. They make a lot of power at first and then they fall apart. Blades snap, seals flood, nacelles fly off, drive shafts bend...and they’re made sturdily enough. As another commenter said, if the current is strong enough to make the power it’s strong enough to rip them apart.",
"The density of water means that there is heaps of power available in flowing water. However it also means that the maximum loading that the turbines need to withstand are much greater.\n \nThere have been lots of different types of tidal stream and waver power devices, but many of them break from a case of extreme loading that they cannot handle, or wear out too quickly from things like cavitation.\n \nWith that said, hopefully we will be able to find something that can withstand the harsh environment, as tidal power in particular is a very reliable energy source.",
"They're trying out some new ones in the Pentland Firth just now. They hang down under a pontoon rather than being fixed to the sea floor. It puts less stress on them that way, so they don't come to bits. They're still experimental just now, but the results so far are promising."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
2pdjpf
|
What did people in ancient times think of dreams?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2pdjpf/what_did_people_in_ancient_times_think_of_dreams/
|
{
"a_id": [
"cmvpzce"
],
"score": [
3
],
"text": [
"Well, at least in ancient Egypt, eating feces in your dream meant you were going to become wealthy. B. E. Shafer, ed., Religion in Ancient Egypt: Gods, Myths, and Personal Practice (Ithaca: Cornell University Press, 1991).\n\nIn Mesopotamia, dreams were usually matters of interpretation. Some advanced scribes who had enough training would go on to specialize in dream interpretation. I haven't spent much time with those texts, but (suffice it to say for an only mildly helpful answer), some thought they were a big deal and had a significant impact on the religion and politics of their time.\n\nWe could also readily consider Joseph from Genesis 37-50, who had several dreams which were then interpreted as being portentous about things to come involving him and his family. Similarly, we see Daniel interpreting dreams for Nebuchadnezzar in the book of Daniel."
]
}
|
[] |
[] |
[
[]
] |
||
31dv0c
|
Why does the elephant have such a big brain? Is most of it dedicated to controlling a massive body?
|
Sperm whales have bigger brains, do they really need one that big?
|
askscience
|
http://www.reddit.com/r/askscience/comments/31dv0c/why_does_the_elephant_have_such_a_big_brain_is/
|
{
"a_id": [
"cudd2do"
],
"score": [
2
],
"text": [
"At its heart this is an Encephalisation Quotient (EQ) question, so we should start there.\n\nMost psychometric texts will talk of [encephalisation quotient](_URL_0_) (EQ) as a better predictor of intelligence than brain size. So many texts state this that that most assume they must be correct. There is only only one small problem: these texts never reference any survey data in support. The reason is that, until very recently, we didn't have any quantitative metric of intelligence that we can use across species. Put simply, it was a wild guess by leading experts borne by the need to explain why elephants aren't smarter than humans (all terrestrial animals have been well studied, and this is the only one of them with a bigger brain than us). We have part of that answer now.\nElephants brains hve recently been studied in detail and have > 97% of their neurons devoted body control and sensory input (in the cerebellum) - much higher than any other mammal. Their trunk is the only other organ that is known to have similar 'dexterity' to a human hand, except hands have a score or so of movable joints, but a trunk has hundreds of muscle blocks to control. The assumption is that controlling these is what has driven their brain expansion over time. In their higher centres (neocortex) they have far fewer neurons than humans, and slightly less than other great apes. It should be no surprise then that they are still thought to be slightly less intelligent that chimps. Now let's go to more recent data on EQ.\n\nFor quite some time now, EQ has been know to be [invalid for primates](_URL_3_) – the group on which most psychometric analysis has been performed. If you go to the Wikipedia page on EQ, you will find the only survey it links to shows that raw brain size is by far the best predictor of intelligence in non-human primates. Until last year, we never had a quantitative metric that could take us beyond comparisons within that one order. We now have one, and (so far only one) survey that can. The stunning surprise from it is that, once more, [raw brain size is far and away the best predictor of intelligent behaviour](_URL_1_), and, if we adjust brain size for body size this predictive power for complex behaviour almost vanishes. So what is my guess as to the true answer to your question?\n\nI think elephants may well need that great brain - but only to control the trunk. Sperm whales may also need theirs to be huge, but for reasons that have nothing to do with body size. Sperm whales are the ONLY animal for which the culture to which they belong [has more impact on its growth rate and reproductive success than its genetics or location](_URL_2_) there are other reasons too to expect that their social complexity rivals or exceeds even our own. [Here](_URL_4_) is my own webpage that gives further details and peer reviewed references to that possibility."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Encephalization_quotient",
"http://johnhawks.net/weblog/reviews/brain/maclean-brain-size-self-control-2014.html",
"http://www.jstor.org/stable/27823483?seq=1#page_scan_tab_contents",
"http://www.researchgate.net/publication/6321027_Overall_brain_size_and_not_encephalization_quotient_best_predicts_cognitive_ability_across_non-human_primates._Brain_Behav_Evol",
"http://cachelot.com/culture/"
]
] |
|
3mq23p
|
Do some plants legitimately have medicinal properties?
|
[deleted]
|
askscience
|
https://www.reddit.com/r/askscience/comments/3mq23p/do_some_plants_legitimately_have_medicinal/
|
{
"a_id": [
"cvh7ok0"
],
"score": [
4
],
"text": [
"Your question sort of has two sub-questions that are non-trivially distinct:\n\n1. Do plants (used as a plant or plant extract) have medicinal properties?\n\n2. Do plants (any component thereof) have medicinal properties?\n\nAs to the first, the court is still out on the vast majority of candidates, save a few known examples (such as cinchona and willow bark for malaria and painkilling, with evidence for marijuana piling up). One of the difficulties in measuring efficacy is that each plant produces a very diverse cocktail of many compounds, and are wildly variable in how much of any given compound they make between individual plants. The lack of control in compound production in plants/fungi makes it preferable to isolate active compounds for drug development - you can control dosage far more easily, and adverse effects are minimized to only what the active compound itself does.\n\nThis leads into the second question, where the answer is overwhelmingly yes. Basically, if a plant is found to be truly (or even potentially) medicinal, it usually undergoes a lot of analysis (screening) until the active compound is identified, purified, and modified to either amplify efficacy or reduce adverse effects. Two major historical examples are the aforementioned willow bark (to aspirin) and cinchona (to quinine). In more recent times, two major cancer drug families, the taxanes (such as Taxol) and camptothecin-analogs (such as Camptosar) were derived from pacific yew and camptotheca tree bark respectively. It's estimated that around 60% of drugs on the market are derived from natural sources, the majority of which come from plants or fungi.\n\nSo basically, yes, a few plants are medicinal and many have compounds that can potentially be medicinal, but the vast majority need pharmaceutical development to be worthwhile.\n\nA relatively unbiased review on the subject can be found [here](_URL_0_)."
]
}
|
[] |
[] |
[
[
"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2658564/#b2"
]
] |
|
wuefz
|
how does mazda's rotary engines work?
|
I consider myself pretty mechanically inclined for the most part, but I just can't grasp the concept of Mazda's rotary engines...
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/wuefz/eli5_how_does_mazdas_rotary_engines_work/
|
{
"a_id": [
"c5gjts5"
],
"score": [
4
],
"text": [
"_URL_0_ \n\nAnyone who has owned an RX7 will get this. \n"
]
}
|
[] |
[] |
[
[
"http://ih0.redbubble.net/image.10534006.8846/sticker,375x360.png"
]
] |
|
2vfjsf
|
When the Titanic sunk due to hitting an iceberg, how iceberg filled was that part of the ocean?
|
Were they in iceberg teratory or was it a berg that had drifted south and was reasonably unexpected?
Was this a common thing?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2vfjsf/when_the_titanic_sunk_due_to_hitting_an_iceberg/
|
{
"a_id": [
"coh6svh",
"coh8png"
],
"score": [
3,
3
],
"text": [
"The Titanic had taken a somewhat more northerly route than most liners normally had, and it was also sailing into an area (near the Grand Banks) where it had received warnings of floating bergs. At the time, no large ship had been lost to an iceberg, and it was thought that bergs did not pose a large danger to contemporary ships. (A similar passenger liner had rammed an iceberg in 1907 and was able to complete its voyage, though with damage.) \n\nSo yes, the ship was in known iceberg territory, which was not uncommon, and cutting the corner slightly closer to Newfoundland than most ships did, but there would not have been a sense on the ship that the situation or those waters were unusually dangerous. ",
"not saying this isn't an r/askhistorians thing (it definitely is!) but are you cross posting this at something like r/askscience? "
]
}
|
[] |
[] |
[
[],
[]
] |
|
985l7t
|
Any studies of the changing preferences for androgyny vs. polarized masculinity and femininity through history?
|
Topic. I’d love any recommendations for books or articles on the subject!
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/985l7t/any_studies_of_the_changing_preferences_for/
|
{
"a_id": [
"e4dfvcf"
],
"score": [
2
],
"text": [
"if the topic is overly vague: specifically I’m interested in any correlations between a timeline of these trends and the corresponding social moment, especially in terms of the political economy"
]
}
|
[] |
[] |
[
[]
] |
|
1rzuyt
|
how does netflix stream movies in high quality smoothly while youtube can't even stream a minute long video without buffering?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1rzuyt/eli5_how_does_netflix_stream_movies_in_high/
|
{
"a_id": [
"cdsj22e",
"cdsjq4n",
"cdsjzur",
"cdska27",
"cdskfaa",
"cdskn1r",
"cdskrld",
"cdskrqx",
"cdsku01",
"cdskxkv",
"cdsky4s",
"cdslc4k",
"cdsled5",
"cdslphf",
"cdslyg5",
"cdslz0t",
"cdsm0dj",
"cdsm52s",
"cdsm7lf",
"cdsmc3m",
"cdsmdur",
"cdsmkvo",
"cdsmpyv",
"cdsmufb",
"cdsmzk3",
"cdsn3pg",
"cdsn6rr",
"cdsnihv",
"cdsnlx5",
"cdsnmx0",
"cdso2qj",
"cdso518",
"cdsoxe1",
"cdsp51q",
"cdsp5jo",
"cdsp78t",
"cdspo9u",
"cdsq4m5",
"cdsq9w1",
"cdsqf9l",
"cdsrnd0",
"cdsrvmd",
"cdssweu",
"cdst7xu",
"cdsteju",
"cdsur3z",
"cdsv386",
"cdsvvka",
"cdswsdw",
"cdswwyh",
"cdsx991",
"cdsy18j",
"cdsy63y",
"cdsyp4f",
"cdsyqvz",
"cdsz3f6",
"cdt228j",
"cdt54ca",
"cdt6r7g",
"cdt7yfz"
],
"score": [
27,
3266,
164,
26,
216,
31,
8,
3,
8,
68,
903,
3,
2,
2,
2,
3,
3,
3,
3,
19,
3,
4,
3,
3,
4,
15,
2,
2,
2,
2,
4,
2,
2,
2,
8,
3,
5,
24,
3,
2,
19,
10,
4,
2,
6,
2,
2,
7,
2,
2,
3,
4,
3,
7,
2,
4,
2,
2,
2,
2
],
"text": [
"This might have more to do with your internet connection and how your ISP has set up its network - depending on how your ISP deals with making partnerships with other networks/ISPs in the area, its possible that YouTube's content delivery servers are slow because your ISP doesn't have the infrastructure or partnership deals to provide sufficient bandwidth/reliability to those servers.\n\nEdit: The process of ISPs making deals as far as how to work with neighboring ISPs/backbones/networks is [Peering](_URL_2_), and depending on how those peering agreements work, its possible either a Netflix CDN (content distribution network) or Youtube CDN are on the wrong side of a bad peering arrangement.\n\nEdit Edit: I assume some people might feel like 'no its because youtube sucks lol.' Your ISP *is* involved, whether actively through some form of bandwidth throttle, or because of crappy peering agreements for your area. [Guides like this](_URL_1_) wouldn't exist (or work) if that wasn't the case. I'm not saying ISPs are responsible for all of this, but if you look at the reaction to Netflix attempting to create a system where [bad peering agreements](_URL_0_) wouldn't be an issue, then clearly there is something else to this beyond 'youtube sucks.'",
"You pay for netflix",
"Netflix posts isp scores, so there is a consequence to slowing them down. I do not believe the same is true with YouTube ",
"ISP are in a war against Youtube. They want Google to pay for bandwidth.",
"Short answer: Netflix has purpose built (or contracted) a well designed [Content Delivery Network] (_URL_0_) with specialized technology designed solely for delivery of streaming media to paying subscribers. Google/YT, who must be all things to all users, also has a major CDN but there's a huge difference in purpose, scale, cost, mission (ad delivery, tracking), load and technology between the two. ",
"That's strange. When Netflix came to Finland, I tried it for a month, but I didn't continue the contract, because it was so slow. Youtube here streams 1440p with no noticeably buffering even on long videos, but Netflix couldn't handle even 720p.",
"The main problem is the video player. In order for YouTube to keep better tracking of who is watching what everytime you click somewhere else it has to re buffer. If you recall the pre-Google era of YouTube (yes, Google didn't own YouTube in the glory days) you didn't have to worry about clicking around the areas of the video that had already buffered. The video player sucks by design.\ntl;dr Porn sites have better streaming because they don't care if you skip to the good part",
"[Lately, they don't.](_URL_0_)",
"The main reason is that Netflix is devoted to and can afford a higher-quality experience for its users.\n\n- Netflix\n\nVideos are controlled by Netflix themselves. No need to worry about converting files server-side or checking videos for copyright infringement, and aside from some minor stuff like star ratings the servers are entirely devoted to serving up content. This means they can afford to buffer your videos well beyond the current point, especially since its users pay for the content.\n\n- YouTube\n\nAnyone can upload video, anytime. Google's YouTube-related servers have to balance converting video, scanning video for illegal/copyright-infringing content, handling comments and uploads from billions of users, and streaming to an audience that dwarfs Netflix. Their servers are filled with garbage like \"my recent webcam upload\" or \"my shitty 200-play Let's Play with 5 views per video\". And people don't pay for a cent of it. And with all this going on, you also have to deal with guys mass-downloading your videos despite using protected streaming methods to deliver video only at the exact moment it's requestied (hence the constant buffering when you skip - notice that almost every other site will buffer the video significantly further than the point you're watching).\n\nSo is it any wonder that Netflix is faster?",
"Youtube uses a system called [DASH playback](_URL_0_), essentially breaking up the video into small pieces and sending the pieces to you individually according to what your network connection can handle. Ideally this improves playback quality without added waiting times since you're always getting the best quality segment that you can receive. If you have an unstable connection, you'll just get a lower quality segment sometimes, but it \\*should be fairly transparent to the person watching.\n\nIn practice, at least on youtube, it's fucking terrible and everyone hates it. It's responsible for constant buffering, performance issues when streaming on a low powered computer, inability to rewatch a part of the video without rebuffering, etc. etc.\n\nThere's an extension called Youtube center that will let you disable DASH, I highly recommend it.\n\nAs for Netflix, I'm unsure if it supports DASH or not, but if it does it has a much better implementation.\n\nedit: Since people keep replying with same-ish info, some clarifications:\n\n* There's nothing inherently bad about DASH or adaptive streaming in general, it's just the way Youtube uses it that causes a lot of problems for people.\n* Some of the blame might also go to Flash, or to your ISP, or to somewhere else in the chain. \n* Some fortunate people have no problems with DASH playback, which is nice for them because it will mean DASH probably give the benefits it's supposed to with minimal or no downsides.\n* Similarly some unfortunate people might have problems with youtube even with DASH disabled. Can't help you there, sorry :(",
"You are referring to DASH Buffering. DASH buffering buffers youtube videos in blocks instead of the whole video. You should disable DASH buffering in order to load the entire video. [Click here for instructions to disable DASH buffering](_URL_0_)",
"Netflix uses Amazon's data centres. Whenever the site needs more computing power, they add more virtual machines to handle the load. My cousin works for Amazon cloud services. Dropbox uses amazon as well. ",
"Netflix has invested a lot of time and money in deploying a content delivery network. Youtube has not (to the same extent).\n\nIt's also worth considering that Netflix has a finite video library that probably numbers in the tens of terabytes. Youtube's content library numbers in the Petabytes - meaning it is a much more complex problem to solve. I can build a single box computer that stores all of Netflix's library, that isn't possible with Youtube. ",
"There is a proven method to increase the speed of youtube videos load time.. I cannot recall it off the top of my head.. but you blocked a certain IP address and it forced youtube traffic through other nodes which ran faster.. While ISPs are not specifically throttling youtube... what they are doing is forcing 90% of youtube traffic through the same core nodes and it cant handle all that traffic.",
"I'm not a tech person, but surely the most obvious two answers are:\n\na) You pay for netflix. They can balance subscription fees against delivering content. They only add things to the library which they think will make profit by attracting more people. Youtube has billions of videos, and very few of them would ever create profit.\n\nb) Netflix library is finite and entirely controlled by them. Youtube library must be 1000's of times larger, and they have to deal with uploads/conversions too.",
"There really are a number of factors here, I'l try to give some of my ideas on why. \n\n*1) YouTube is free, Netflix is paid. It's safe to assume YT gets perhaps and order of magnitude of traffic.\n*2) Technology: Netflix uses Silverlight with a Windows Media Codec (Last I checked it was WM9, but it might have been axed for h.264 all together) Youtube uses Mpeg and h.264. Windows Media is quite good at streaming. It has variable speed detection and adapts on the fly. Youtube's mechanism for this is to down shift in quality. Swapping quality on MPG in the middle of a video is a rather new-ish way of handling it.\n*3) Backbone: The internet backbones can throttle traffic from destination to destination depending on load. If one pipe is full of YT traffic, it'll throttle it via QoS (quality of service, which is traffic prioritization).\n*4) Netflix is in Amazon's datacenters. This one is likely of no substance, but Amazon is used to large amounts of media traffic.",
"(Disclaimer I am by no means an expert so feel-free to correct me! This is what I was told by a friend who works in the content delivery industry)\n\nVideos are kept on what's called a CDN, a content delivery network. This is a big net of servers spread across the land, and they hold copies of.. content! Now, YouTube tries desperately to make sure every video loads fast - but obviously this is a pretty daunting task (keep in mind how many videos YouTube has versus Netflix - it's not even close). So, since they don't have unlimited space and instant transmission across the world, what happens is a computer system moves files around inside of the CDN based on demand. If there's a viral trending video, you're going to have copies of every resolution on every content server around the country - so that requests for this video are as snappy as possible. On the other hand, some random video that only a couple hundred people have watched in the past 3 years is not as widespread. It has fewer copies, in fewer locations - based on lack of demand, hence, it's more susceptible to delays in getting to you. Keep in mind a given youtube video might come in 5 resolutions. You think it's the same video, but it's really 5 different copies of the video in different resolutions - and each copy might have different levels of demand. So if you've ever wondered why the 1080p version loads better than the 720p... well that's simply because more people have been wanting 1080p, so that version of the video is more widespread on the CDN. As a result the majority of end-users will find the 1080p version easier to access than the 720p. On an individual basis, this can be maddening - but in the big picture, it's an elaborately managed and very dynamic system trying to keep the highest average performance possible for the most amount of people.\n\n\nIn contrast, Netflix has a lot less data to manage, a lot fewer requests... so this is all purely speculation, but perhaps Netflix just doesn't allow gaps in their CDN? They maintain every copy on every node?\n\n\nJust a theory based on off-hand knowledge. (edits for grammar/clarity)",
"My youtube works fine. Always. I'm not sure what reddits obsessions is with bashing youtube lately. I don't know a single person outside of the reddit who has constant problems with youtube",
"I don't understand why I seem to be in a minority for which Netflix is inconsistent and often unwatchable. I can load one episode in full HD, and the next drops the quality to minimum and can't keep up with buffering. I have 30-50Mb/s, through Comcast and I don't see any connection dropouts from other applications. If one were so inclined, an entire season can often be acquired through other means before Netflix can buffer the opening scene of an episode.",
"ITT: Like 90% people speculating.",
"In addition to all of this, Netflix also does a lot of awesome analytics on movies and shows that you are going to stream to get the content closer to your physical location *before* you watch it.\n\nFor example, if a few people in your area are watching Breaking Bad Season 1, Netflix knows based on previous customers that you have a high likelihood of watching Season 2. Season 2 files are then mirrored to a physical server, likely in your ISP, before you even click \"play\" on S02 E01. Physical proximity is important, as it reduces latency (better speed) as well as cost.\n\nVery popular shows are stored on massive, very fast hardware -- if I recall correctly, they are served from SSDs, whereas less popular shows are stored on slower hardware.\n\nISPs love these local caching servers, as it reduces the amount of bandwidth they have to purchase from upstream providers.\n\nIn addition, Netflix's streaming library is much smaller than the YouTube library.\n\nYet further, Netflix pre-generates stream files for different devices and connection speeds. If you're on a slower connection, you automatically get adjusted to a lower-quality stream. This is why you'll sometimes see an HD stream suddenly get a little less crisp -- Netflix hedges that users would rather continue watching their show in a bit lower quality than to have it stop and buffer.",
"YouTube has a thing on it that stops it from pre-loading, Netflix doesn't. You can install things that turn that thing off on YouTube, and then it loads extremely well and plays through with no buffering. I'm on my phone right now, but I think the one I use is YouTube center or something? Someone link that if you know it. ",
"Depends on your cable provider. Youtube instantly loads once I got youtube center and a VPN connection. It circumvents the throttling.",
"Get the userscript YouTube Center and then disable dash playback. It also fixes other YouTube annoyances. ",
"Because Youtube is a free service and Netlfix isn't? Come on guy, you should know the answer.",
"DevOps here, we've done an analysis of Netflix streaming, and the fact is that Netflix sends several streams at once over the wire. Your local client has an algorithm to switch between streams finding the optimal one, and even collating them if necessary. The local client also sends constant information back to Netflix, that's why they always know exactly where you left off. \n\nThere are also facts about their smart Content Delivery Network, which is mostly on top of Amazon Web Services, balanced and optimized for local delivery. Netflix also works with major Internet Service Providers to create a local Content Delivery Network to serve that specific ISP.\n\nThere are other facts and techniques they use to develop, build, deploy, and serve the Netflix service. All in all, in my field (DevOps), Netflix is one of the few companies that innovate in awesome ways.",
"When you ask for a video, Netflix has 5 answers and YouTube has 5000. Imagine how quickly you could answer a question if you've answered it 1000 times today already versus being YouTube and answering it for the first time in weeks.",
"and how is vimeo so much better technically in every way than youtube. \n\nIts free (to debate all the \"because you pay\" comments)",
"It streams so much faster with HTML5 webm video. I suggest switching to HTML5 video. This script forces HTM5 as default for Youtube. There's also some suggestions that Google intentionally makes flash videos in Firefox not work as well to make people switch to Chrome. No clue if there's any truth to that. \n\n_URL_0_\n\nIt's a little buggy since you have to update it every time there's any change to Youtube itself. ",
"I highly regret the notion that I don't \"pay\" for google. First and foremost, the google products that I use personally I pay dearly for. I pay by providing them with a constant, intimate stream of market research. Their entire business platform depends on the intricate data they receive from ME (and every other user), without us using their \"free\" products, they would have no income stream from... and this leads me to the second way I \"pay\" for google. My company realizes that google is GOOD at advertising to the right people at the right time, so in turn we pay huge ad dollars (almost $100k this year) which is a lot for a small/medium sized business and we have great returns on our google ad dollars. a lot of these dollars goes toward development of new products like gmail, android, maps, etc. \n\nSo google offers NOTHING for free. Youtube is very much paid for by every user that watches videos and ads. \n\nBalancing bandwidth at YouTube is very intricate and touchy, they load balance based on the popularity of video, along with several other aspects including your connection history, they algorithmically try to guess how much video to stream to you at what speed in order to try to stay JUST head of the glitch curve. When this breaks down is when you're dealing with mobile devices which notoriously jump all over the place. Mobile connections can also have inconsistent ping times which plays a big part in video streaming. If you settle on a connection profile with youtube, start steaming a video, and your ping time jumps to 100ms+.. youtube could have never predicted that, so they do their best to play catchup, but it still can result in a glitch. \n\nRest assured, every time your youtube client stalls a video the connection info is logged and these logs are poured over by google engineers in order to tweak the algorithm and improve it. \n\nsource: I'm somewhat connected to someone inside, and we've had detailed conversations about this exact issue.",
"The reason is quite simple:\n\nImagine you go to a video shop that has thousands of movies and you ask for a title, the store clerk will start looking for it maybe by it's name and then go retrieve it from the right shelve, as most movies are popular, that store makes sure the most requested titles are available on the closest shelve so you don't have to wait, then the store clerk give you your movie and you are on your way. This is what happens for netflix, just look for a poppular title among maybe in the thousands of movie titles.\n\nNow, for youtube, imagine you go into a book store that has almost everybook everyperson has written, no matter how long or short the book, 600 pages or just two paragraphs, so this book store has millions and millions of books, if it's a book the youtube book store has to have it, now you go ask for a popular book, of course the librarian is going to have it at hand and hand it to you, however to make sure you read the whole thing and not just grab the whole book and not read it completely he's going to start giving you only two pages of the book at the time when you are done with one page the librarian is going to give you another page, this is buffering, usually it performs well, but then again, a lot of people complaint about the youtube book stote retrieving time, Why does it take so long for the librarian to come back with a request book? because the most unpopular books are stored somewhere in the library so the librarian has to send someone to retrieve that book for you and have you wait, \n\nThat takes a lot more times as there are millions of books to look into, and there's so many book shelves it takes more time that looking through a few thousands of movie titles.\n\nThis is the main reason why youtube ads play right away, they are popular videos and are ready to be fetched right away, even the hottest videos play right away thanks to this approach, but ask youtube for a really old video and you'll have to wait until a small robot goes to the storage inside Youtube Datacenter and retrieves the video, sometimes that small robot might delay and your video won't play at all until you refresh the page one more time. Netflix has an easiest job at the video store.",
"For me Youtube is far better at streaming than Vimeo, which tends to just sit there like a rock most of the time.",
"one is free an one aint. now go to bed.",
"Because flash is a horrible unoptimized platform that uses far more resources than it needs.",
"The question is simple, but the answer is far more complex. Netflix and YouTube might seem like they'd be similar on the surface, but at their cores they aren't. Netflix works within a very limited set of parameters to provide you with digital content supplied by professional publishers, where YouTube has a HUGE amount of unknowns that they're working with because literally anybody can be a content publisher recording in any format at any number of different qualities and they're providing it for free.\n\nWatch this video for a much more in-depth explanation on buffering from two engineers at Google: _URL_0_",
"Im not sure where/what you watch on netflix but for the past few months that shit has been straight potato quality for me. ",
"Originally posted by /u/Ryokukitsune\n\nYouTube has a feature called \"Dash Playback\" that it hasn't really nailed down yet. its a good concept but not very good in practice as most people have figured out. the reason for this is Dash takes advantage of a process called JIT or Just In Time to stream. it buffers 5-10 seconds of video at a time then stops. they developed this for two reasons, one to put a Governor on downloads during peak hours and to accommodate users with spotty internet connections.\n\nDash is supposed to resume once the end of the buffer is reaches but as we all know that's not reliable sometimes for a plethora of reasons, most common ones are errors in a browser (easily solved by restarting a few times in a blue moon) or misconfiguration of browsers blocking the feature and the unlikely scenario of ISPs blocking the cache servers that the player looks for.\n\nin contrast to Dash there is linear streaming which downloads a clip from start to finish. Every file you get on the internet from HTML to an FLV \"streamed\" to you from YouTube is downloaded in some way. you are not really getting tiny bits, you are getting the whole file, they just tend to be protected in temp directories now regardless of how they are downloaded. \n\nlinear streaming was a problem in the beginning when YouTube didn't have a bunch of cache servers around the world. videos would stop buffering on bad internet connections forcing users to refresh the page and hope it buffered past a problem point. now that YouTube has gotten much bigger its not really a big worry unless you have one of those crappy connections.\n\nThe problem however is that Dash is enabled by default, there is no easy way to disable it without digging threw a few obscure Google back pages and even then its kind of cryptic as to what you are actually agreeing to.\n\nI have found a plugin called \"YouTube Center\" for FireFox and Chrome that adds options to YouTube that will juggle the various setting for you including disabling Dash or defaulting player type and resolution to something other than the Flash version.\n\nas for why Netflix can provide a better experience over YouTube, Darth hit on it pretty well. Youtube is a free service and limited by the resources Google throws at them. they have done a good job of keeping the community afloat (sans g+ integration) but are trying to keep up with user volumes, content rights and technology on a very public stage.\n\nNetflix on the other hand exists in a different realm with less demanding requirements to a certain point. most of their content is licensed and limited meaning they don't have to have as much resources for new content on a regular basis. they can create as many cache servers as they need to support a more consistent viewing experience without making compromises to quality or users because most of those features have been built in from the start. \n\n**Tl;Dr** YouTube has Dash, dash is bad. I have a solution but you'll have to read to find it. \n\nNetflix has less stuff to host and can have more servers to pick up the slack when the internet demands it. they both have features to preserve the viewing experience but it depends on your network or theirs...",
"[you really want to know don't you](_URL_0_)",
"I use Netflix on an almost daily basis, and while it's a great service, it does have some flaws. During peak viewing periods (example, on weekends), I've notice that the quality of video changes frequently while playing. Sometimes it's HD, and other times the video is blurry and choppy. I have not experienced any \"buffering\" per se, and it might just be my shitty internet (Comcast), but I have yet to experience the flawless streaming everyone's raving about.",
"YouTube uses a DRM and anti copy mechanic called DASH, this means it only buffers small parts of the video at a time, then once you have almost finished watching that it buffers the next little bit. It will start deleting the parts you have already watched.\n\nDASH is designed to prevent people from downloading videos from YouTube, it was one of the conditions the music industry required before they would put their videos on youtube.",
"better question....why did you post this in two threads?",
"Posting this to Askreddit wasn't enough?",
"And meanwhile, a 15 second gif takes 2 minutes to load.... ",
"Really? I have an easier time streaming youtube in HD than netflix.",
"ELI5: How does the same question posted in two different subreddits by the same user end up [right next to each other](_URL_0_) on my front page?\n\n",
"Damn, /u/chuloreddit, banking on the Karma with this question. Ask Reddit AND ELI5? What's next, /r/pics?",
"Explain like you're 5? Easy. Here's the link the same question you asked and was answered: _URL_0_",
"* YouTube's free to play. **(Less money to throw around)**\n\n* Netflix is pay to play. **(More money to throw around)**\n\n* YouTube has hundreds and thousands of videos uploaded to it's servers each day, these all have to be converted. Netflix uploads a movie once. **(More work for YouTube, less work for Netflix)**\n\n* YouTube has a MUCH higher user base than Netflix **(More work for YouTube, less work for Netflix)**\n\n* The typical use of YouTube is 10~ connections to YouTube's servers to view 10 different videos, rather than 1 connection on Netflix **(More work for YouTube, less work for Netflix)**\n\n* YouTube doesn't pay any money to ISP's for bandwidth, Netflix does (rumored) **(More work for YouTube, less work for Netflix)**\n\n* YouTube has users who upload duplicated material stolen from another person's YouTube channel **(Even more useless work YouTube's doing because of a user's greed**\n\n* YouTube also has A LOT of comments being posted every second, which again takes up a lot of bandwidth, cpu... etc\n\nIf I'm right in thinking they both use the same sort of technology, just one gets priority and one doesn't.\n\nFor example in the United Kingdom, the iPlayer (BBC), 4OD, ITV Player... etc all stream beautifully for most UK residents that's because they don't have as much work to do, not as many people viewing their content and they get network priority.",
"YouTube has a feature called \"Dash Playback\" that it hasn't really nailed down yet. its a good concept but not very good in practice as most people have figured out. the reason for this is Dash takes advantage of a process called JIT or Just In Time to stream. it buffers 5-10 seconds of video at a time then stops. they developed this for two reasons, one to put a Governor on downloads during peak hours and to accommodate users with spotty internet connections.\nDash is supposed to resume once the end of the buffer is reaches but as we all know that's not reliable sometimes for a plethora of reasons, most common ones are errors in a browser (easily solved by restarting a few times in a blue moon) or misconfiguration of browsers blocking the feature and the unlikely scenario of ISPs blocking the cache servers that the player looks for.\nin contrast to Dash there is linear streaming which downloads a clip from start to finish. Every file you get on the internet from HTML to an FLV \"streamed\" to you from YouTube is downloaded in some way. you are not really getting tiny bits, you are getting the whole file, they just tend to be protected in temp directories now regardless of how they are downloaded.\nlinear streaming was a problem in the beginning when YouTube didn't have a bunch of cache servers around the world. videos would stop buffering on bad internet connections forcing users to refresh the page and hope it buffered past a problem point. now that YouTube has gotten much bigger its not really a big worry unless you have one of those crappy connections.\nThe problem however is that Dash is enabled by default, there is no easy way to disable it without digging threw a few obscure Google back pages and even then its kind of cryptic as to what you are actually agreeing to.\nI have found a plugin called \"YouTube Center\" for FireFox and Chrome that adds options to YouTube that will juggle the various setting for you including disabling Dash or defaulting player type and resolution to something other than the Flash version.\nas for why Netflix can provide a better experience over YouTube, Darth hit on it pretty well. Youtube is a free service and limited by the resources Google throws at them. they have done a good job of keeping the community afloat (sans g+ integration) but are trying to keep up with user volumes, content rights and technology on a very public stage.\nNetflix on the other hand exists in a different realm with less demanding requirements to a certain point. most of their content is licensed and limited meaning they don't have to have as much resources for new content on a regular basis. they can create as many cache servers as they need to support a more consistent viewing experience without making compromises to quality or users because most of those features have been built in from the start.\nTl;Dr YouTube has Dash, dash is bad a little broken. I have a solution but you'll have to read to find it.\nNetflix has less stuff to host and can have more servers to pick up the slack when the internet demands it. they both have features to preserve the viewing experience but it depends on your network or theirs...",
"My Netflix buffers in the evenings",
"I like how someone can post the same question to both AskReddit and ELI5 and they both make the front page.",
"Youtube can stream ads pretty well",
"Sorry if this has already been posted, but I believe the answer is largely related to net neutrality and the willingness of ISPs to carry content from particular online providers.\n\n_URL_0_",
"Except for youtube advertisements. That shit is HD quality",
"Netflix eats up bandwidth like a fat man at buffet eats up shitty buffet food.",
"$7.99 a month plus tax",
"I might not be correct, but it's also related to your ISP [obviously]. Since YouTube has such a gigantic traffic-feed, ISP's throttle (and charge YouTube/Google a lot) for using such a large portion of their network. Again, I might not be correct. But Netflix has a much smaller traffic, and doesn't have to process thousands upon thousands of gigabytes of video every second like YouTube does. YouTube also goes in blocks, which is why rewinding a buffered video isn't instantaneous, as that 'block' of the video is no longer downloaded. However, Netflix uses Silverlight streaming, which I have no idea how it works.",
"How? Assholes being assholes.\n\nISPs throttle the Youtube connections.\n\nIt's for this same reason that everyone else has Netflix just fine but when I try to use it the damn site glitches up and asks for me to sign up and pay them money I don't have.",
"Because Youtube has DASH enabled, while Netflix doesn't.\n_URL_0_",
"amount of people waching. and SLA cost/benefit. service level agreement.\n\nsla up to 95% availability and low latency is dirty cheap. any .1% on top of that costs exponentially (taking numbers from my ass. will not reasearch to talk to a 5yold)\n\nyoutube has lots of people watching short crap cat videos. so initial caching/buffering is void. ...end of video cached? too bad, user clicked cat with pancake on head thumbnail. also, little delays will not bother free users (they are the product etc)\n\nnetflix has much less users. users watch the same video 30min to 2h, so caching/buffering is awesomely effective. and users are paying their increasingly monthly price while seeing the content diminish (where the fuck is sponge bob, netflix?!) so they demand that netflix provides for better sla.\n\n (1st comment of the day, and i got a \"you are doing this too much\". why do i bother?)"
]
}
|
[] |
[] |
[
[
"http://gigaom.com/2013/06/17/time-warner-cable-no-we-dont-throttle-youtube-its-all-about-peering/",
"http://mitchribar.com/2013/02/time-warner-cable-sucks-for-youtube-twitchtv/",
"http://en.wikipedia.org/wiki/Peering"
],
[],
[],
[],
[
"http://en.wikipedia.org/wiki/Content_delivery_network"
],
[],
[],
[
"http://www.digitaltrends.com/home-theater/getting-hd-netflix/"
],
[],
[
"https://en.wikipedia.org/wiki/Dynamic_Adaptive_Streaming_over_HTTP"
],
[
"http://lifehacker.com/preload-entire-youtube-videos-by-disabling-dash-playbac-1186454034"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"http://userscripts.org/scripts/show/87011"
],
[],
[],
[],
[],
[],
[
"http://gizmodo.com/how-youtube-works-1466547461"
],
[],
[],
[
"http://i.imgur.com/V9JxgbS.png"
],
[],
[],
[],
[],
[],
[],
[
"http://i.imgur.com/CaYFpPr.jpg"
],
[],
[
"http://www.reddit.com/r/AskReddit/comments/1rzu3l/how_does_netflix_stream_movies_in_high_quality/"
],
[],
[],
[],
[],
[],
[
"http://arstechnica.com/information-technology/2013/07/why-youtube-buffers-the-secret-deals-that-make-and-break-online-video/"
],
[],
[],
[],
[],
[],
[
"http://en.wikipedia.org/wiki/Dynamic_Adaptive_Streaming_over_HTTP"
],
[]
] |
||
h4zlu
|
What does intergalactic space look like?
|
If you were in a spaceship between galaxies, or even in a giant void, such as the [Boötes Void](_URL_0_), what would you see when you looked out the window? I imagine you'd see mostly blackness instead of the standard starry night sky that we see when we look up from earth. Would you see distant galaxies as points of light, or perhaps small blobs?
Is there *anything* out there between galaxies? Any drifting debris that escaped the gravity of galactic bodies and slipped out into intergalactic space?
|
askscience
|
http://www.reddit.com/r/askscience/comments/h4zlu/what_does_intergalactic_space_look_like/
|
{
"a_id": [
"c1sm7tf",
"c1snqzb",
"c1spajp"
],
"score": [
83,
4,
2
],
"text": [
"Disclaimer: I am a layperson.\r\n\r\nThe sky would be different--it would be completely black to the naked eye if you were at the center of the Boötes Void. At 250 million light years in diameter, if you were in the center, the closest galaxy would be 125 million light years away. The Andromeda Galaxy is our closest non-dwarf galaxy neighbor at only 2.5 million light years away and magnitude 3.44, and it's a barely-perceptible splotch in the night sky. If it was 125 million light years away, it would be 2500 times fainter, at a magnitude of 11.9. The faintest object visible with the naked eye is magnitude 6 or below (higher magnitudes are harder to see. Also, it's a logarithmic scale.). Even if you had a telescope, you would only be able to observe galaxies. No stars (except for bright supernovae within the galaxies), no nebulae, nothing. Just distant galaxies that you'd have no hope of ever reaching.\r\n\r\nFor all practical purposes, there probably wouldn't be anything larger than a [mote of dust](_URL_1_) for light years around you. I can't access the article referenced in this Wikipedia entry, but I believe it focuses on intergalactic dust *clouds*. The space between these clouds (which are probably few and *very* far between) will be filled with a [rareified hot plasma](_URL_2_) with a density of a few tens of particles per cubic meter.\r\n\r\nThere are some [extragalactic stars](_URL_0_) that have been observed, but, considering that they'd necessarily be much rarer than stars in a galaxy, you'd probably be hundreds of thousands of light years from one, on average, if not further (just my guess based on nothing more than a hunch). See also [hypervelocity stars](_URL_3_).\r\n\r\nEdit: The galaxy brightness calculation above assumes the galaxy is similar to the Andromeda galaxy. The brightest galaxies are about ten times brighter, so they still would not be visible from the center of the Boötes Void.",
"If you are travelling in a convential space craft, going slower than light, you certainly wouldn't see stars flash by your window. I hate that in some movies...",
"Reminds me of a David Deutsche TED talk: _URL_0_"
]
}
|
[] |
[
"http://en.wikipedia.org/wiki/Bo%C3%B6tes_void"
] |
[
[
"http://en.wikipedia.org/wiki/Intergalactic_Stars",
"http://en.wikipedia.org/wiki/Intergalactic_dust",
"http://en.wikipedia.org/wiki/Outer_space#Intergalactic",
"http://en.wikipedia.org/wiki/Stellar_kinematics#Hypervelocity_stars"
],
[],
[
"http://www.ted.com/talks/david_deutsch_on_our_place_in_the_cosmos.html"
]
] |
|
bywccq
|
Collapse of the Tatars
|
I’m aware that the Tatars were remnants of Genghis Khan’s Mongol Empire and that they spent decades preying on the Russian Principalities but how did they all die? Because I feel like they did not last for that long. Did Russia conquer them all? Were they destroyed by rebels? Did something else I’m not aware of happen to them? What was their fates?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/bywccq/collapse_of_the_tatars/
|
{
"a_id": [
"eqofsnq",
"f363boa"
],
"score": [
3,
2
],
"text": [
"I wrote an [answer](_URL_0_) on the history and idea of Tatars a few months ago, that might be of interest.\n\nThe rough idea is that a Chingissid state called the \"Golden Horde\" , which in turn broke up into a number of successor states, that were conquered by Muscovy/Russia in the 16th-18th centuries.\n\nBut Tatar people didn't \"all die\". There are still millions of ethnic Tatars! There are a number of different Tatar communities, the largest being the community in Russia that largely lives along the Volga River near the city of Kazan. Volga Tatars are the second-largest ethnic group in Russia after ethnic Russians, and have their own autonomous republic known as Tatarstan.\n\nAnother significant community of Tatars lives in Crimea, currently under Russian control. Large numbers of this community emigrated to Anatolia in the 19th century, when they stopped being a majority of the population, and the whole community was deported to Central Asia by the Soviet government in 1944 (they were allowed to return in 1991). \n\nThere are smaller communities of Tatars in Siberia, and in Poland-Lithuania, the latter known as \"Lipka Tatars\". This group is mostly assimilated into the local population (although some remain practicing Muslims), but have played a role in Polish history, notably aiding in the Polish defense of Vienna against the Ottomans in 1683. Some more famous people of Polish heritage who have Lipka Tatar ancestry include Charles Bronson and Martha Stewart.",
"Many make a mistake by putting an equal sign between the Tatars and the Mongols. We have not only different languages (Tatars belong to the Turkic group and are therefore closer to Turks or Uzbeks), but also the origin itself. Tatars went from the Turkic people of the Bulgars, and the Mongols have a completely different ethnogenesis.\n\nTatars themselves suffered from the Mongols as well as the Russians. The ancient city of Bulgar was destroyed by the Mongol conquerors, and its inhabitants conquered. But later, due to the small number of Mongols, they assimilated with the local Türks and formed khanates like the Golden Horde, which had some of the attributes even from the Mongols and where Genghisides ruled, that is, descendants of Genghis Khan. And initially it, and then other khanates on its land, kept Russian principalities and surrounding peoples at bay, but over time they weakened due to internal unrest, which resulted in the conquest of Muscovy (I personally hold the view that Russia essentially became the heir Golden Horde and other khanates, as she subjugated all the former khanates and headed for a similar policy.)\n\nWhat happened to the Turkic peoples conquered by the empire of Russia? They still live, some got freedom, some, I hope, will get it in the future."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/akql3m/what_is_tartary_does_it_exist/ef7b5ro/"
],
[]
] |
|
aasfr1
|
The Goonies got me to wondering -- was there ever any actual piracy along America's Pacific coast? If so, what was it like?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/aasfr1/the_goonies_got_me_to_wondering_was_there_ever/
|
{
"a_id": [
"ecwrkqx"
],
"score": [
7
],
"text": [
"Most of the piracy along the America's Pacific Coasts were privateers, not piracy, and were limited to the South American Coast. It tended to not be as blood thirsty and prisoners were routinely released. And it was nowhere near as common as it was in the Atlantic, Caribbean/Gulf of Mexico and African coasts. \n\nKeep in mind that Spain had a pretty good strangle hold on Pacific Ocean and guarded the Southern Passage between the Pacific and Atlantic Ocean's pretty heavily between Drake's voyage and into the 1800s. On top of that, the Spanish didn't like to advertise that ships had been lost so they tended to keep things quiet when they were. They routinely surpassed ships logs and maps created by even their own explorers in an attempt to keep the \"undiscovered\" \"Northwest Passage\" a secret from other European powers. But even in the Pacific Ocean and with all their military might they still ran huge heavily armed Galleons and trade fleets to discourage piracy. \n\nThe other huge problem is logistics. From the 1500s through to the 1750s or so, Spain ruled the Pacific Coast and many the coastal cities there. From about the area of San Francisco northward was \"unsettled\" land populated only by Indians. If you were a pirate there were few places to go to get supplies or sell the treasure so you had to attempt to cross the Atlantic to China or India, or sail back around through the Southern Passage. There are some rumors of Spanish Pirates working the Pacific Coast, which makes sense as they would have been able to hoist up the Spanish flag before sailing into port to sell their goods. \n\nThe most famous privateer was Sir Francis Drake. He was involved in several expeditions as early as 1563 on the African Coast and in the Caribbean. In 1572 he commanded an expedition that successfully raided around Panama in 1572-73, and even captured the Spanish Silver Train at Nombre de Dios. That success led to Elizabeth I sending him to the Spanish owned Pacific Coast and in 1578 he captured a Spanish ship near Lima, and then chased down and captured the treasure ship Cacafuego. From there his travels are murky, speculation is that he may have sailed as far north as 55 degrees Latitude before turning around due to the cold weather. That would have put him somewhere about the Alaska Peninsula. He definitely claimed land for England. The exact location he did so is still unknown but today is generally accepted as being Drake's Bay in California. He might have even planted a colony there, an fact that is supported by how many less men he had later on. But the English falsified Log books and maps to keep Spanish spies from getting them. And all of them from this expedition were lost in a fire in 1698 at Whitehall palace. \n\nFrom there out most piracy was at the hands of Privateers actively challenging Spain's military might and supporting various South American countries in their attempts at independence from Spain. In the late 1700s England was directly challenging Spanish control of Pacific Coast between Northern California and Alaska. The Russians were pushing down the Alaska coast, and Spain was still dealing with rebellions through out South America which had severely sapped their military might in the previous centuries. A lot of these privateers were working incognito to dodge Spanish Spies in Europe, and again records were still routinely falsified so concrete evidence is hard to find. \n\nThe Spanish pushed back at these incursions. In 1789 the Nootka Incident happened after Esteban José Martínez seized two British and two American ships in order to strengthen Spanish Claims on Nootka Sound. The ships were later returned, and a treaty between America, Britain, and Spain established a trading zone that all three countries violated years later. Two of the ships involved in this incident (but not seized,) are still well known. One was the Columbia Ridiviva, of which the Columbia River was named after. The second is the Lady Washington, who's replica is a well known tall ship used in the Pirate of the Caribbean Movies.\n\n & #x200B;\n\nBut.... \n\n & #x200B;\n\nThere are also tantalizing Native American legends all up and down the Pacific Coast that tell tales of what can only be ship battles and ship wrecks. Stories of huge \"war canoes\" crewed with light skinned men and creating clouds from their decks are a common tale. Men landing on beaches, killing captives and then burying them and heavy chests on the beach. Early explorers running across extremely fair or dark skinned Natives who must have taken ship wrecked crews into their tribes, Chiefs of tribes who are of obvious African decent, and even an occasional gold or silver trinket. Many of these legends still fuel rumors of pirate treasure, one of the most famous being of a location called \"Neahkahnie Mountain.\" [Here is a copy of the legend I picked up many years ago for those who want a flavor of the tale](_URL_1_). I personally know people who still travel here after every major storm with metal detectors and shovels. \n\nIt doesn't help that for many decades [huge slabs of beeswax were found washed up on shore nearby](_URL_0_) directly fueling further speculation of treasure. \n\nThere are enough tales that I find it hard to believe that a portion of them aren't true, even accounting for people stretching the truth. \n\nAnother tale surrounds Iron Jim Sallow, who was said to have buried treasure somewhere around what would become Seattle. But any information about him is of the same, rumors and uncertain stories with no evidence to back them up. In fact I can not find a single primary source for him, and suspect he may be a creation of one of the local \"Pirate\" groups that put on shows throughout the summer. \n\n & #x200B;\n\n & #x200B;"
]
}
|
[] |
[] |
[
[
"https://oregonencyclopedia.org/articles/beeswax_shipwreck/#.XCldQy3MyL4",
"http://pnwphotoblog.com/legend-of-treasure-on-neahkahnie-mountain/"
]
] |
||
5s8i03
|
how will autonomous cars handle not being able to see the road, ie snow
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5s8i03/eli5_how_will_autonomous_cars_handle_not_being/
|
{
"a_id": [
"ddd7ftb",
"ddd7gn7",
"ddd7sj9",
"ddd7tmq",
"ddd8c1s"
],
"score": [
3,
29,
6,
15,
6
],
"text": [
"Unless road standards are followed perfectly and the roads mapped exactly, the extreme conditions will still defer control to the driver. \n\nThe typical rules the car has to follow will not be applicable in extreme conditions. \n\nYou could see it the same as a car driving across the desert. Where are the lanes? \n\nSnow could additionally interfere with sensor functionality depending on the type. ",
"It certainly will be harder for an autonomous car to do this than normal driving.\n\nEarly autonomous cars will likely have a failsafe mode, where if they can't handle the road conditions, they will pull over and return control to the driver. \n\nAlso remember that these cars will have a lot of advantages, like 360^o vision, radar, IR, and future enhancements might allow them to talk to the road and to each other. What might appear as a white out to us would be no different than a sunny day to them.",
"All these cars have LIDAR and radar to sense other cars and things around them. They use cameras to see road signs and lane lines. So you are right that the lines on the road disappear as far as the cars sensors are concerned but like us the car can see things like curbs and sign posts. Basically as the tech becomes more prevalent cars will map out road sign posts and curbs using LIDAR and radar. When the camera cant see the road it will match terrain contours, road posts, curbs and anything else it can detect with radar and LIDAR to previous information or maps of the given GPS coordinates. The programming has been used in other areas for years so its not super difficult just tweaking it for autonomous vehicles and creating usable databases of all the roads is kind of a big task. ",
"Right now it's not advised to use autopilot in snow. With that said there are plans to where it will be ok in the future and there are different ways to do it. One is to create detailed surroundings which include data sent from the cars themselves when conditions were not snowy. This allows the car to look for multiple different markers (curbs, telephone poles, signs, and other landmarks) to determine its location and drive in the same way as previous cars did in good conditions.\n\nThis of course has issues with rather rural areas with little historical data and in those instances the car will advise not using autopilot.",
"The same way that you do when you can't see the road - you do your best to get by with other visual cues other than the road itself, and information you have access to. Vision is just one aspect, there are many cameras of many types as well as recieving other kinds of data i.e GPS, lidar, physical sensors. The software controlling these things are getting better also. You don't just track the road itself, you track all objects and their spacing and their motion and parallax, their shape, how they're lit etc etc. Just like in your brain there are areas that track edges in your vision, and within there there's bits that deal with angles of those edges and so on, in addition to areas that track colour, brightness, occlusion etc. all of this information is put together into a model that you use to make decisions. We're improving it's models of the world beyond simply tracking the floor. "
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
||
2i5dao
|
What was religion like in the Palmyrene Empire?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2i5dao/what_was_religion_like_in_the_palmyrene_empire/
|
{
"a_id": [
"ckznolz"
],
"score": [
2
],
"text": [
"Like other religions of the Near East of the time. The polytheist religion of Palmyra worshiped a number of gods and goddesses. There was the triad of Beelshamem, Aglibol, and Yarhibol- who represent storm god, moon god, and sun god. Other gods worshiped there include Baal Hammon, Manat, El, Allat, Poseidon, Shamash, Bel, Arsu and Azizu (the twin gods of morning and evening stars).\n\nCheck out 'The Pantheon of Palmyra' by Javier Teixidor. There's plenty of information in there about the various gods and goddesses worshiped by the Palmyrenes.\n\nAs for the empire itself under Queen Zenobia, it would include the local cults of the gods of the people conquered, as well as Jews and Christians, in addition to the gods worshiped in Palmyra itself."
]
}
|
[] |
[] |
[
[]
] |
||
welfw
|
What would be the consequences for the neighbouring areas of the Atucha Power Plant in Argentina if it underwent something similar to other known nuclear disasters?
|
askscience
|
http://www.reddit.com/r/askscience/comments/welfw/what_would_be_the_consequences_for_the/
|
{
"a_id": [
"c5cpsjw",
"c5cpzpj"
],
"score": [
6,
2
],
"text": [
"Just some context: the [plant](_URL_0_) is by a river, some 100 km upstream from Buenos Aires. What would be the risk to the city?",
"You aren't really asking a question that is answerable in any clear defined scope. Plants within their design basis will virtually never have an accident. Plants outside of their design basis (Chernobyl, TMI, Fukushima) will, and the results are unknown because it is outside of the analysis for that plant. At that point, the best you can do is look at the general consequence outcome. See something like the NRC's SOARCA [(State of the Art, Reactor Consequences Analysis)](_URL_0_) for a decent overview.\n\nIf you ask a more specific question, I would be able to help out more. If you have any nuclear specific questions such as how accidents progress, or consequences let me know."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Atucha_I_Nuclear_Power_Plant"
],
[
"http://www.nrc.gov/about-nrc/regulatory/research/soar/overview.html"
]
] |
||
euj350
|
why is texture so important in our enjoyment of a food?
|
I just had pad thai. Why is it that it wouldn’t taste as good if I put it in a blender and then ate it? It would contain all the same flavors and nutritional components. What is it that makes texture so important and therefore, makes food like hamburgers or pad Thai taste undesirable when blended up?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/euj350/eli5_why_is_texture_so_important_in_our_enjoyment/
|
{
"a_id": [
"ffpr3h9",
"ffpto7e",
"ffq67fc",
"ffq67vx"
],
"score": [
66,
23,
4,
2
],
"text": [
"Texture is a major indicator of food quality. A carrot that's mushy isn't good. We develop expectations for what foods are supposed to be like texture-wise and deviation in these expectations set off our reptile brain alarms",
"Since in general most vegetables and fruits change their texture when they go bad bad, our brains automatically think that the different texture could be the food having gone bad. It makes us not like it so we don't get potentially poisoned by it",
"Have you actually tried a blended Pad Thai though?",
"Using Thai as an example each element (salt, sweet, acid, fire) different parts of your toung senses different flavors. Texture of the components, noodles, peanuts, sauce add to the experience. Blend it and the uniqueness of the flavors are lost as well as the nuances of texture."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
1s32my
|
skylanders. specific questions about what things are.
|
I can't figure this out, previous posts didn't ask about the right thing, and I can't find the answers on Google either.
Here's what I've been able to sort out. There are three types of Skylanders:
1) Skylanders (series 1)
2) Skylanders Giants (series 2)
3) Skylanders Swap Force (series 3)
Here's the facts I *think* I know. Feel free to tell me if these are wrong:
1) The stand thing that you put these on, connects to the console via USB and is... console agnostic? And also works with all three series' of Skylanders? So it doesn't matter what stand thing (sorry, Portal of Power) you have as long as you have the disc for the toys you have or newer?
2) The game disc itself, there's one for each of those three types I assume (Skylanders, Giants, and Swap Force).
3) I see these adventure packs... with like... other stuff besides characters. Like physical items. Swords and chests and shit. What's all THAT stuff about? Is it actual new levels for the game? If so, do they work regardless of which game disc you have (Skylanders, Giants, or Swap Force)? Do you just put those extra things on the Portal of Power along with whatever Skylander you're using?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1s32my/eli5_skylanders_specific_questions_about_what/
|
{
"a_id": [
"cdxbqor"
],
"score": [
2
],
"text": [
"1. The series 1 and series 2 are the same thing/interchangeable/etc, as far as I know, but the series 3 portal is different due to the swappable characters in Swap Force. As for the portals connectivity to the different consoles, so far that I've seen from various comments, only the Xbox One doesn't register other systems portals.\nSo, with the newest portal, all characters, series 1-3 work with it.\n\n2. Yep.\n3. Some of the things are new levels. Some of them are for example, a cannon that pops up and helps you out by attacking enemies. You put them right on the portal alongside the Skylander. Not all of the level unlocking items from Spyro's Adventure and Giants unlock a level in Swap Force, though."
]
}
|
[] |
[] |
[
[]
] |
|
4ue9mk
|
Were civilians able to cross "borders" during the US Civil War?
|
Suppose I live in the Confederacy. I'm planning to travel (business or pleasure), and I say to myself, "Well, I've been to Richmond and Atlanta. How about New York City?!" What would have happened had he tried to cross a border and visit New York? Would he have been allowed to do so? Let's say he makes to to New York (or any Union city). Would he have been arrested just for being there?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4ue9mk/were_civilians_able_to_cross_borders_during_the/
|
{
"a_id": [
"d5q5wzh"
],
"score": [
2
],
"text": [
"It was definitely possible, though it wouldn't have been without considerable hassles, and a few favors cashed in along the way. So, I assume by the way OP phrased the question that they are referring to sanctioned crossings through enemy lines (and not stealth missions where permission wasn't granted). In this case, yes, it was possible for civilians to cross from the Confederacy into the Union (and vice versa). We definitely have some examples of this, too. What was needed in most cases was a pass (a letter, really), granting specific permission for one person to move through a military district or region. These would have been written personally by the military commander in charge of that area, or someone very near the top of the military pecking order in that region. Yet even this would have only helped a person get out of an area, and would have done only so much to get them into the OTHER \"enemy\" region. For example, British observer Arthur Fremantle arrived in Texas in March 1863, and worked his way all the way to Richmond in time to move with Lee's army towards Gettysburg. Strictly an observer, Fremantle had managed to get permission from various generals along the way to move freely through the Confederacy, until he got a pass from Robert E. Lee himself attesting to his neutral status (the note essentially promised that Fremantle was not a spy). This pass allowed Fremantle to travel north into Union lines to continue observing (though it wasn't without some suspicion...however, Lee's note actually got him pretty far). The fact that Fremantle had several notes from high ranking Confederate officers attesting to his neutral status (and the basic fact that he was British) surprisingly got him into the Union, so it shows that such movement was possible under the right circumstances and with the right people attesting for them. \n\nOn the flip side, Mary Todd Lincoln had a half-sister named Emilie Todd Helm, which made her Abe Lincoln's step half-sister. Emilie Helm's husband fought and died for the Confederacy, and Mary Todd asked Abe to grant Emilie a pass north so that the woman could visit for purely social reasons after the death of Helm's husband. Lincoln granted the request, and after the visit, wrote a pass for Emilie to go back south, which was honored. Obviously, if the president gives the okay, soldiers manning checkpoints are obliged to allow passage, so again, it wasn't without precedent for such a request to be granted. \n\nThis was not a normal occurrence, however, and would have required a high-ranking individual to sign the pass allowing movement, and some level of trust on the other side to recognize the validity of the enemy pass, and accept that the person was not a spy (so, a pass signed by Lincoln or Robert E. Lee would have been looked upon as fairly safe, as their \"word\" on the matter was seen as somewhat sacrosanct). \n\nA normal person without political connections on the level of Lee or Lincoln would have needed a pass from the commanding general in the area to get out of that side's lines, and would have needed some pre-arranged agreement to get into the other side's lines (so a parlay would have needed to have been called, where it was established that a person was coming through, and agreements would have been made to allow it based on extenuating circumstances). \n\n[Sources: Doris Kearns Goodwin, 'Team of Rivals'; Bruce Catton, 'Glory Road']"
]
}
|
[] |
[] |
[
[]
] |
|
1l0dkq
|
how does image compression like .jpg work? a 500x500 pixel image can vary massively in filesize depending on 'detail' and file extention
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1l0dkq/eli5_how_does_image_compression_like_jpg_work_a/
|
{
"a_id": [
"cbuitvg"
],
"score": [
5
],
"text": [
"Compression, in general, aims to remove redundant information. Some forms of compression, such as a zip file, do this without much special knowledge of what it is compressing, and also has to make sure it can get back the exact data before it was compressed (ie be lossless). \n\nOther types of compression are specialised, such as audio (eg mp3), video (mp4), or images (jpg). Because they are specialised, this allows them to throw away information people don't perceive and to use clever tricks that improve compression vs lossless techniques. \n\nSo in the case of jpg, tricks are used to intentionally drop the quality of the image vs the original, but in ways that are only minutely perceptible. By focusing on aspects of the image we notice (edges, colour gradients etc) and degrading others (blocks of colour, textures) high compression can be achieved without losing much visual quality. \n\nIts the ratio between these important bits and the unimportant bits that determines how compressed it can become. A scene full of interest, colour and shapes? Not much can be thrownaway, so big file. A scene of a polar bear in the snow? Lots to throw away, small file. \n"
]
}
|
[] |
[] |
[
[]
] |
||
1z1etm
|
why do pc's become slow and "aggravating" to use after little time, but macs seem to stay at top performace for a long time?
|
Every time I buy a PC it gets slow after literally a few weeks. Even if I run ccleaner, clean the registry, etc. But, it seems to me that Macs do not have this problem. Why?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1z1etm/why_do_pcs_become_slow_and_aggravating_to_use/
|
{
"a_id": [
"cfpn3fh",
"cfpnel2",
"cfpo00d",
"cfpqo3j",
"cfpvm6y",
"cfqiaxr"
],
"score": [
3,
3,
2,
2,
2,
2
],
"text": [
"IT professional here: Can you please define \"slow\"? This word is thrown around often when it comes to computer complaints but details matter. Is it taking a long time to boot up? Is netflix choppy? Is it slow when you open a third powerpoint deck? Those can help me answer you better.\n\nThe shorter answer is RAM, that helps keep things quick. Additionally, macs I have found are less inclined to have background processes initiated and installed silently. When you hit ctrl-alt-Dlt and go to task manager, then to the \"processes tab\" that shows you all of those things your computer is doing that you can't see. That list may be longer and thus taking up more of the computer's resources than it is on a mac.",
"There are several reasons, but what I have found to be very effiective at speeding up a Windows PC is to disable prefetching.\nPrefetch is a mechanism where Windows, at least up thought Windows 7, loads a small piece of every program you've used recently into memory, in an ironic attempt to make them load faster.\n\nIf you disable prefetch (it's a registry setting) and clean out the prefetch folder under the \"Windows\" folder you'll find that booting and a lot of general operations will speed up.\n\nGoogle \"Windows Prefetch\".",
"I hear people complain about this a lot, but I have yet to experience it. I'm using a PC I built in 2010 (using fairly outdated parts at the time) and it's still pretty performs the same as day 1.\n\nAre you cleaning the dust out?\n\nAre you running more programs than before?\n\nAre you defragging your HDD?",
"Yeah this is a misnomer. I've used both PCs and Macs, they both get a little bogged down after years of use. Like other people on here are saying, you need to be more specific when you say it gets slow. \n\nWhat sort of programs do you install? What websites do you visit? What browser do you use? What kind of computer do you have? What are its specs? Where did you buy it? \n\nThere are a lot of things that could be making your machine slow. ",
"I don't know the OPs expertise level, but I generally find that Windows PCs become slow and useless when novices are allowed to have access to an administrator-level account.\n\nI built a new computer for a relative that always had \"computer problems\". On the new build, she did not get access to an admin account. The computer still runs fast, 2+ years after it was built.",
"Everybody knows that Windows machines slow down after some time of use. Why all the deniers here??\n\nSome of the explanations seen here:\n\n1. \"Dust\" lol\n\n2. You damaged it by performing incorrect administrator actions.\n\n3. It was always slow and you just didn't notice it.\n\nReally helpful...\n\n"
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
|
6e2rai
|
why are there different levels of sunscreen? wouldn't someone want to use the highest level that is most effective against sunburns?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6e2rai/eli5_why_are_there_different_levels_of_sunscreen/
|
{
"a_id": [
"di794yf",
"di79apn"
],
"score": [
11,
12
],
"text": [
"[Here](_URL_0_) is an article detailing some issues with high SPF sunscreen with points that include:\n\n* High SPF only give marginally better protection, SPF50 blocks 98% of uvb rays, SPF100 blocks 99%\n* Different chemicals (or concentrations of chemicals) in high SPF sunscreen may cause different adverse effects for people.\n\nAustralian regulations cap SPF ratings at 30 with other countries capping them at 50 or 50+ since there is generally little difference once you go beyond those numbers.",
"Because SPF 100 sounds way more awesome than SPF 15 and people might pay more money for it. \n\nThe difference between sunscreens above SPF 50 is basically negligible. SPF 15 blocks about 93% of the harmful UV features from the sun. SPF 30 about 97% and SPF 50 blocks 99%. Any higher and you're just adding fractions of a percent of additional protection. So yes, higher levels of sunscreen are \"more effective\", but are you more likely to get a sunburn with SPF 50 than SPF 100? Not really. "
]
}
|
[] |
[] |
[
[
"http://www.ewg.org/sunscreen/report/whats-wrong-with-high-spf/"
],
[]
] |
||
2k4dpw
|
how are large, intricate corn maze designs made?
|
The huge one of Peyton Manning, for example.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2k4dpw/eli5_how_are_large_intricate_corn_maze_designs/
|
{
"a_id": [
"clhs81y"
],
"score": [
2
],
"text": [
"Using a board with strings attached to each end, the artist holds a string in each hand and keeps the board under foot pushing the cornstalks down with the board and using the strings to pull the board back up. The board is used to keep a uniform width of the lines in the corn, and the motion of kicking down and then pulling up the board helps them do this rapidly.\n\nTL;DR Aliens"
]
}
|
[] |
[] |
[
[]
] |
|
2vwx4k
|
when companies like facebook track their user's activity to sell it, who do they sell it to? and what do the buyers do with the data?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2vwx4k/eli5_when_companies_like_facebook_track_their/
|
{
"a_id": [
"collfp7",
"collfw2",
"colmknm"
],
"score": [
2,
3,
2
],
"text": [
"Facebook doesn't sell it, not directly. What they do is they use it to target ads. If I'm making a product that I think will appeal to 18-22 year old women who like hip hop and live in the southern US, I can go to Facebook and pay them to show my ad to just those people (and then I don't have to worry about getting charged for my ad being viewed by 60 year old Norwegian men who clearly want nothing to do with my product). ",
"Have you ever used Hulu, and seen one of those ads that asks you to pick the one that is most relevant to you? Basically, companies like Facebook are selling user data so that marketing companies can do this without additional input and target ads to you. ",
"Advertising companies to target their ads so they can target their ads at specific people/groups (e.g. an eight-year-old boy obsessed with professional wrestling will have no use for menstural products or car insurance, but could be interestsed in WWE merchandise.) "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
93a4mp
|
Can anyone recommend a good book of world maps with political borders from various periods throughout history?
|
I think this question fits this subreddit, but if it doesn't can someone suggest a better fit?
I am looking for a gift for a child who is fascinated with what the political borders of the world were at different times and how they evolved into what they are today.
I have looked a various listing of books, but it is often unclear exactly what maps are in the books or what the quality is (full page? Color?). I am hoping someone here can vouch for a book they think would be a good fit from personal experience.
A specific request from the kid is a world map predating the formation of the USSR. I tried to find a globe of that, but they all seem so expensive. It seems the best bang for the buck would be a book. (although I would rather have a globe to avoid issues arising from projections).
Any help is appreciated.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/93a4mp/can_anyone_recommend_a_good_book_of_world_maps/
|
{
"a_id": [
"e3chken",
"e3dm9tg"
],
"score": [
2,
2
],
"text": [
"I can't give you any advice on the pre-USSR map specifically, but one I can personally vouch for is [this book](_URL_1_) called *Great City Maps*. It's a full-color collection of various surviving maps of great cities dating from Roman times up until about 1900. There are a couple of maps of Moscow and a couple of maps of St. Petersburg in there.\n\nI have it and it's a pretty great coffee table book. You're not going to get a huge in-depth study of any particular city, but the maps are all big and colorful, and are full reproductions of the originals. So you'll see stuff like a map of London in 1572, and the text will point out some of the highlights on the map from then, and what still exists and what doesn't and, to some extent, what happened. It also serves as a good overview of the history of maps, as you can see how much more detailed and accurate they got over the centuries.\n\nYou can see the table of contents in the link above, and a few more pages can be seen in [its Amazon preview](_URL_2_). Hopefully, that gives you enough to see if it's worth it. It should be said that the pages in the preview are from the first pages in the book, which are the oldest maps. As they move into the 1400s and later, they begin to have the detail that we're now used to. The dimensions of the book are large, so it looks better in real life than it does in the preview.\n\nBy the same publisher is [*Great Maps*](_URL_4_) which seems to be basically the same thing, except the maps are mostly country-wide, or continent-wide instead of city maps.\n\nFor the Russian maps, though I can't vouch for them myself, it looks like [*Restless Empire: A Historical Atlas of Russia*](_URL_0_) from Harvard University Press and [*The Penguin Historical Atlas of Russia*](_URL_3_) from Penguin Publishing are going to be two of your best bets. They both have smaller dimensions than the *Great Maps* books, but the *Restless Empire* book is 8.5\" x 11\"--the standard size of a sheet of paper. The Penguin book is smaller.\n\nI hope this helps. Good luck!",
"The Cultural Atlas series has come out from several publishers, including Stonehenge, Facts on File, and Time-Life. *The Cultural Atlas of Russia and the Former Soviet Union* would be your target. It would have maps as the primary source of information with photographs and short essays on the development of countries in this area. I don't have this particular volume, but among the modern ones, I've found China and Japan good. (There are historical atlases in the series, like Ancient Egypt or The Greek World.)\n\nLook for it at Amazon, _URL_0_, and Ebay to find best condition at best price.\n\nGenerally, what you're looking for is called an historical atlas. That is, it shows the world as it was, like pre-Revolutionary France or colonized Africa, rather than the present day. "
]
}
|
[] |
[] |
[
[
"http://www.hup.harvard.edu/catalog.php?isbn=9780674504677",
"https://books.google.com/books?id=j4CNDAAAQBAJ&printsec=frontcover",
"https://www.amazon.com/Great-City-Maps-DK/dp/146545358X/",
"https://www.goodreads.com/book/show/235017.The_Penguin_Historical_Atlas_of_Russia",
"https://books.google.com/books?id=0HkRBAAAQBAJ"
],
[
"Alibris.com"
]
] |
|
1syh0s
|
How did the Romans brush their teeth
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1syh0s/how_did_the_romans_brush_their_teeth/
|
{
"a_id": [
"ce2xbai"
],
"score": [
2
],
"text": [
"The Natural History by Pliny the Elder is a very good source for this. \nA substance called *dentifricium* which was quite similar to our toothpaste was produced from powdered pumice [Plin. HN 36.42](_URL_1_) (\"Considered medicinally, pumice is of a resolvent and desiccative nature; for which purpose it is submitted to calcination, no less than three times, on a fire of pure charcoal, it being quenched as often in white wine. It is then washed, like cadmia,5 and, after being dried, is put by for keeping, in a place as free from damp as possible. [...] dentifrices, too, are prepared from it\"), or the calcinated bones of several animal species (e. g. the ashes of deers horns, wolf's heads, heads of mice, the pastern-bone of an ox). The latter are mentioned in [Plin. HN 28.49](_URL_0_) which is generally a good read on roman dentistry. \n"
]
}
|
[] |
[] |
[
[
"http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.02.0137%3Abook%3D28%3Achapter%3D49",
"http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.02.0137%3Abook%3D36%3Achapter%3D42"
]
] |
||
8aaly5
|
When did rhyming in poetry start? What culture implemented it, and how did it get passed on to the way we view rhyming poetry today?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/8aaly5/when_did_rhyming_in_poetry_start_what_culture/
|
{
"a_id": [
"dwxn1qb"
],
"score": [
3
],
"text": [
"I will presume you're thinking of European poetry of Dante, Cavalcanti and Petrarca in particular as rhyme is found across the world, [including pre-Columbian America](_URL_0_) and [Ancient China](_URL_1_).\n\nUntil a better answer comes around I'll discuss the academic opinions known to the modernist poet Ezra Pound way back in the beginning of the century. \n\nThe problem with writing a narrative is that we will have to connect dots of poetry different times and in different languages and these dots can be connected in different ways.\n\nWell, the Florentine language poets explicitly harkened back to the troubadours of the Provence (Jaufré Rudel, Bernart de Ventandorn, Daniel Arnaut...). Their culture and language came to a downfall with the Cathar Crusade in the 13th century, but, presumably, *their* example has also been followed in Germany (Minnesang) and went, through France (Trouvères), to England, with the Anglo-Norman poets Maistre Wace, Richard the Lionheart and Tumas de Britanje. For some reason, they are rarely even mentionned as *English* poets, so that you get a gaping nothingness between the Middle English of a Geoffrey Chausser and the Beowulf. \n\nSpeaking of which: one of the academic opinions mentionned by Pound seeks the roots of a troubadour's rhyme in such Germanic staff rhymed poetry as Beowulf and the Ludwigslied. Here academics (mostly German ones) count the lines that rhyme and come to the conclusion that a fashion is arising to rhyme together with the middle ages. The French academics instead sought the beginning of troubadours in North Africa (which happened to be French at that time), by drawing parallels between Andalusian Arabic poetry (such as that of ibn Zaydun) and, through christian Spanish folk poetry (such as the cantigas de Santa Maria), to Southern France. Pound finds the French position more convincing than the German one but we still have no explicit credit given by any of the troubadours."
]
}
|
[] |
[] |
[
[
"http://www.mexicolore.co.uk/aztecs/home/aztec-poetry-2-three-poems",
"https://ctext.org/book-of-poetry"
]
] |
||
24j50j
|
Does World War I actually deserve the title of World War?
|
My vague impression of it is that it was contained to Europe and parts of the Middle East. Was there major fighting in the rest of the world that actually warrants the name?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/24j50j/does_world_war_i_actually_deserve_the_title_of/
|
{
"a_id": [
"ch7o52h",
"ch7okkl",
"ch7styc",
"ch7to32"
],
"score": [
21,
13,
3,
2
],
"text": [
"The UK in 1914 was a world power having bases and territory directly and indirectly under its control on every continent. \n\nGermany also had land (though much smaller then the UK) on several continents.\n\nThere where battles that took place outside of the trenches and the middle east. For example the [Siege of Tsingtao](_URL_1_) was in the Pacific while the [Battle of Coronel](_URL_0_) was in South America.\n\nThus we can see Battles taking place in South America, Africa, China, Europe, and the Middle East. By any definition that is world wide combat. \n\nHowever it is also considered a world war because it involved thanks to Empire every continent and almost all the major power of the day. The US, Russia, Germany, France, UK, Italy, and Japan where all involved.",
"The majority of the fighting took place in Europe (the Western and Eastern fronts, Italy, the Balkans, Gallipoli), but non-European Ottoman territory saw plenty of combat, too (Egypt/Palestine, Arabia, Mesopotamia, the Caucasus). The naval war stretched around the world, with German commerce raiders active in the Pacific and Indian oceans early in the war, and major battles at Coronel and the Falkland Islands. On land, the German colonies saw varying degrees of conflict: most of Germany's colonies fell very quickly, but Paul von Lettow-Vorbeck led a successful guerilla campaign in German East Africa which lasted until the end of the war.\n\nStill, *most* of the fighting was in Europe. But there's another reason to call WWI a *World* war--belligerents from all over the world participated. Tens of thousands of soldiers from the British Commonwealth, as well as the British and French colonial empires, fought in Europe and elsewhere. Other belligerents included Japan, the United States, and a [long list of others](_URL_0_). \n\nReally, I think the question to ask is whether the First World War actually deserves the title of *First*.",
"The term 'world war' only entered English, most likely from the German term 'Weltkrieg', which means world war, a handful of years before the First World War. Contrary to what the term would lead you to think it didn't mean a war fought across the globe. According to the Oxford English Dictionary the definition of world war was a war involving the world's major nations. Under that definition it was obviously a world war as the world's major nations were involved. \n\n\n",
"/u/winterking07 touched on this a little bit, but there was significant fighting in Africa. German Southwest Africa (Namibia) was invaded by the British, which was initially repulsed before finally succeeding. In German East Africa Paul Von Lettow Vorbeck beat the British at Tanga and then ran circles around an invading South African Army. \n\nThe Japanese attacked Germany's colonies in the Pacific and occupied them. The other instances have been touched on by the other posters.\n\nHowever, there's another reason that I haven't seen why WWI is a global war. Even if most parts of the world didn't see fighting, the vast majority of the world was mobilized for war production, and sent millions of men to fight in Europe. This was because to have the resources to fight such a massive conflict all the major powers had to lean on their Empires, which gave the entire world at least some stake in the conflict.\n\nThe First World War Episode Two: Global War, has a great overview of this. Also, chapter two or three of Peter Hart's \"The Great War\" has a great overview of the naval warfare in a global context."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Battle_of_Coronel",
"http://en.wikipedia.org/wiki/Siege_of_Tsingtao"
],
[
"http://en.wikipedia.org/wiki/Participants_in_World_War_I"
],
[],
[]
] |
|
27yirw
|
How did the lion, an African animal, come to be so prominent in Chinese art and sculpture?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/27yirw/how_did_the_lion_an_african_animal_come_to_be_so/
|
{
"a_id": [
"ci5mhod",
"ci5mk4o"
],
"score": [
9,
10
],
"text": [
"Not a direct answer to your question, but just to point out that historically, the range of the lion extended across much of the Near East and well into South Asia. See [this map](_URL_0_).",
" > an African animal\n\n I can't comment on why Chinese culture focuses on lions, but it's worth pointing out that lions once ranged throughout much of Asia as well. Although by now the only Asian lions left are in the Gir forest in India. \n\nConsidering their [historic range]( _URL_0_), it's not surprising that they could have a significant influence on a lot of Asian cultures"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Lion#mediaviewer/File:Lion_distribution.png"
],
[
"http://upload.wikimedia.org/wikipedia/commons/7/7d/Lion_distribution.png"
]
] |
||
5axzal
|
how do spiders make noises?
|
Today I learned spiders can [scream](_URL_2_) and [purr](_URL_0_) and [buzz](_URL_1_)
How do they do this? They don't have vocal cords, and they're not rubbing their legs like crickets, so....
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5axzal/eli5_how_do_spiders_make_noises/
|
{
"a_id": [
"d9k9zez",
"d9ktrbr"
],
"score": [
91,
8
],
"text": [
"A couple ways.\n\nFirst, they have bristles all around their body that can be rubbed to make purring or buzzing noises.\n\nSecond, some types can force air out of their breathing holes (spiders don't breath through their mouths!) to create hissing or screaming noises (think, like a kettle with air being forced out of it -- or a balloon with air being squeezed out).\n\nEdit: [Here's my favourite spider gif. Conveniently, it's also my favourite ant gif.](_URL_0_)",
"Crickets use the rough edge if their wings not their legs to create the noise btw. The more you know :D"
]
}
|
[] |
[
"https://youtu.be/Et--lFINQOM?t=26s",
"https://youtu.be/yI8_6DgxLTY?t=1m25s",
"https://youtu.be/RTHm9ztSPoc?t=27s"
] |
[
[
"http://iruntheinternet.com/lulzdump/images/gifs/brave-ant-attacking-spider-jumping-13804816675.gif?id="
],
[]
] |
|
5m9kum
|
Old paintings and portraits
|
Always wondered this and thought I'd ask, how come in nearly all older paintings dating back pre 1700's people just look... so weird. Was everyone terrible at painting or did people look a lot different. I know people say it's the style of paint but surely with mirrors around people would look at the paintings of themselves and think 'god thats ugly' just figured I'd ask anyone's insight to this year long mind boggle
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5m9kum/old_paintings_and_portraits/
|
{
"a_id": [
"dc1zsug"
],
"score": [
2
],
"text": [
"Could you specify what you mean by \"weird\"?"
]
}
|
[] |
[] |
[
[]
] |
|
1bf9p8
|
how do billboards work?
|
I am interested in finding out how billboards work.
1. Who owns them?
2. Who regulates them and determines how many billboards can appear in a certain area?
3. Do the landowners where they appear get paid for allowing them to be built on their property?
4. How much do they cost?
5. How successful are they and have they been negatively affected since the Internet (a la the newspaper industry's ads)?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1bf9p8/eli5_how_do_billboards_work/
|
{
"a_id": [
"c96eh6p"
],
"score": [
2
],
"text": [
" > Who owns them?\n\nMost billboards will have a small sign on them that states who owns it. Most in my area are owned by VIACOM. That might be true everyware or not, I assume it depends on area. \n\n > Who regulates them and determines how many billboards can appear in a certain area?\n\nSome city's would have rules where they can or cannot be placed, some don't. It's something that is goverened at the local level.\n\n > Do the landowners where they appear get paid for allowing them to be built on their property?\n\nYes, the company would likely lease a small strip of the land.\n\n > How much do they cost?\n\nAs with all things, this is determined by supply and demand. So billboards that are in high traffic areas would cost much more and ones in the middle of nowhere would cost less. There is no hard price guide. But for the most part they are priced with a large payment to cover the construction of the new sign (you would likely need to provide the design) and then have a monthly rent component depending on how long you wanted it to stay up.\n\n > How successful are they and have they been negatively affected since the Internet (a la the newspaper industry's ads)?\n\nNewspaper adds are down because fewer people are looking at newspapers. As the internet has not affected peoples need to get around (much) I do not imagine there has been much slump in billboard adds. "
]
}
|
[] |
[] |
[
[]
] |
|
1jmgjs
|
Are there other theoretical dimensions that are not spatial or temporal?
|
All the things that I have read about extra dimensions talk about spatial dimensions. Are there other theoretical dimensions that are not spatial or temporal?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1jmgjs/are_there_other_theoretical_dimensions_that_are/
|
{
"a_id": [
"cbg63ek",
"cbgbtqb"
],
"score": [
9,
3
],
"text": [
"In relativity, the difference between a spacial and temporal dimension is how we measure distances. If two events are separated only by time (say you now and you still sitting on your chair in 5 minutes), the distance between these two events is negative (or positive, in the other convention). In the case where the distance is spatial (say you and the statue of liberty, measured now), then this distance is positive (or negative, in the other convention).\n\nThat being said, if you introduce another dimension and require the metric to be real, then this extra dimension can only give a positive or a negative contribution to the distance, thus making it either spatial or temporal.",
"Supersymmetry adds fermionic degrees of freedom in addition to the spacetime-coordinates. At least [some authors](_URL_0_) (pdf, page 15) call this dimensions.\n\n > So we may say that SUSY invites us to\n > contemplate ‘fermionic dimensions’, and enlarge space-time to ‘superspace’.\n "
]
}
|
[] |
[] |
[
[],
[
"http://arxiv.org/pdf/hep-ph/0505105v1.pdf"
]
] |
|
6fblxy
|
how can it been cheaper to buy something new than to repair it?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6fblxy/eli5_how_can_it_been_cheaper_to_buy_something_new/
|
{
"a_id": [
"digyh4a",
"dih086i",
"dih1amb",
"dih3ugz"
],
"score": [
2,
5,
2,
6
],
"text": [
"You have to pay for the labor too. It's not just buying parts, you have to pay for people to spend their time fixing it, and they're trying to make a profit too",
"Manufacturing is a streamlined process. Especially now with automation and years of engineering, it has become incredibly efficient to source materials, form them, and ship them out. Also, since you're making so many, the cost per unit goes down drastically.\n\nWhen you repair, you don't get any of those efficiencies. Unless it's a very routine fix, often someone has open up the contraption and try to find what's wrong. Then they have to order or make any piece that needs to be fixed and install it. It's a decent number of hours for only one machine, and requires someone with an intimate knowledge of how it works, which is expensive. A massive manufacturing plant with robots is just so much more efficient.",
"Making something on an assembly line with 1000's of others is incredibly efficient and the labor costs per item are minor relative to the cost of the good--especially if made in a 3rd world country.\n\nTo fix the item means somebody -- usually a highly trained technician -- had to spend time to diagnose that single item, figure out what needs to be fixed and fix it, along with any part(s) needed, for that single item.",
"Two answers you were given so far reference something called [economies of scale](_URL_0_) which means that making a whole lot of something means each one by itself can be made cheaper than by not making a lot of something.\n\nAnd that's not a wrong answer to your question. But it's also not the only answer to your question. Sometimes the creation process for something is just easier than the repair process. Let me demonstrate with a set of instructions that I want you to imagine yourself doing.\n\n1. Go make a cake. Two layers, with cream and icing, decorated with \"Congratulations\" and little icing flowers on top.\n\n2. Punch the cake. Put a nice big hole in it.\n\nNow you have two options. You can spend time to clean up the splatter, take measurements of the dimensions and volume of the hole, make some extra bit of cake and carve it into the exaact shape of the hole, place in in, fill cream again in the right places, add the bits of frosting needed to complete the words and flowers as they looked before and smooth everything over so you can't see any seems. \n\nOr you can just make a whole new cake.\n\nWhich one do you think will take less time?"
]
}
|
[] |
[] |
[
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Economies_of_scale"
]
] |
||
1ip1zh
|
Does air quality get better after a storm passed through an area?
|
I live in the Philippines, we get monsoons/ typhoons fairly often. We also have one of the most polluted city in the world. Does regular passage of typhoons through our country signifcantly cleanse our air to prevent it from accumulating to dangerously high levels of air pollution? Has anyone studied this in another country?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1ip1zh/does_air_quality_get_better_after_a_storm_passed/
|
{
"a_id": [
"cb6st1b",
"cb6tj89",
"cb6u5x4"
],
"score": [
2,
14,
5
],
"text": [
"This might be of interest:\n\n_URL_0_ ",
"Yes for a time air quality improves after a storm passes through. The mechanism is called \"precipitation scavenging\" in which droplets of rain will absorb particulate matter as they fall towards the ground. This is the primary mechanism - removal of PM in the air.\n\nThere is no Wikipedia page I could find specifically on this subject, but [here](_URL_0_) is a paper from Lawrence Livermore that has a good introduction on the topic.\n\nIncidentally, a scrubber used to remove pollutants from an industrial process (or even mobile ones used for ships at berth) works on basically the same principle.",
"nitrogen oxides are byproducts of combustion of cars and factories. they are what make the air appear brown. when it rains the water picks these particles up through a process called wet deposition. that's why visibility is good after it rains. \n\n\n_URL_0_"
]
}
|
[] |
[] |
[
[
"https://www.google.com/url?sa=t&source=web&cd=6&ved=0CDkQFjAF&url=http%3A%2F%2Fwww.scirp.org%2FJournal%2FPaperDownload.aspx%3FpaperID%3D2618&ei=XPPqUd-2Ke7RigL3q4AI&usg=AFQjCNEk71R1h116Mn2XkQZpYfd-Nx4dlg&sig2=RH5JttULu_DcGvNNz7ui1A"
],
[
"https://narac.llnl.gov/uploads/Loosmore_Cederwall_2004_PrecipScavAtmEnv_155010_isxhz.pdf"
],
[
"http://en.m.wikipedia.org/wiki/Deposition_(aerosol_physics)"
]
] |
|
p5oby
|
Can a deaf person become bilingual?
|
Not phrased well, so an example : A guy looses his hearing at age 10. He has only ever been exposed to English. He learns sign and to lip read, but one day gets a Mexican girlfriend who only speaks Spanish. Could he learn to lipread Spanish, having never heard it before?
Sidenote : I know from personal experience that speaking Spanish to a deaf lip reader messes them up, which spawned this question.
|
askscience
|
http://www.reddit.com/r/askscience/comments/p5oby/can_a_deaf_person_become_bilingual/
|
{
"a_id": [
"c3mpvvb"
],
"score": [
7
],
"text": [
"You're asking a few different questions here.\n\nFirst off, the deaf person in your example is already bilingual in English and a signed language. There are many different signed languages in the world, and they are not based on spoken languages. For example, British Sign Language and American Sign Language are very different, despite the language users' proximity to a shared spoken language - English. In contrast, French Sign Language and American Sign Language are very similar. (As a side-note, there are several signing systems that attempt to combine the syntax of a spoken language with the vocabulary of a signed language. However, these are not naturally acquirable systems, and are really just a subset of the spoken language rather than a true signed language.) So the short answer here is yes, they can become bilingual just like any other person. However, you're specifically wondering about spoken languages, so there's more to my answer.\n\nIt's important to recognize that being able to read lips does not necessarily indicate fluency in the language. A lot of it is very context-dependent. Try this on a friend some time: Let them know you're going to say something silently and ask them what you've side. First, make eye contact, smile, and silently say \"Hello, how are you today?\" Be sure to keep your lip movements as natural as possible. Odds are that they'll understand what youve said fairly easily. Now try \"purple monkey dishwasher\" or some other unexpected combination of words and notice how they are unable to understand what you've said. That's because only 30% of speech sounds in English are visible. Your lips are pretty much in the same position for \"boat,\" \"but,\" \"butt,\" \"bat,\" etc. Your tongue and vocal tract are shaping most of the sound. Hopefully that gives you some idea of how context-dependent lipreading is. This should also show that people who are very good at picking apart contextual clues and have a wide vocabulary of content words (such as nouns and verbs) could get by without a strong knowledge of function words or language structure. Unfortunately, I don't have statistics for speech sounds in Spanish, but I know there are sounds that exist in Spanish that do not exist in English (the trilled r comes to mind.) This is conjecture on my part, but I would imagine that would make lip reading more difficult than it already is.\n\nThe final component is second language acquisition and the age the person lost their hearing. Children acquire language much more readily before a certain age (what exactly that age is is still being fiercely debated, but it is a widely-accepted hypothesis nonetheless.) It's also much easier to learn a second language if you have a first language (more on this in a moment.) So someone who loses their hearing at age 10 is going to have a much easier time acquiring a second language, either spoken or signed, than someone who loses their hearing at 40. However, it's a different story for children born deaf. It used to be, and in many cases still is, that a child's deafness is not discovered until they are several months to several years old. Since 90% of deaf children are born to hearing parents, this also means that the parents have to decide whether they want to teach their child a signed language first (which the parents have to learn and are unlikely to become fluent in,) or whether they want to try to force the child to learn their spoken language (a good analogy is \"like trying to read Sanskrit without ever having heard it spoken.\" That is, it's hard to explain to an infant the connection between the fact that their parents seem to move their mouths when looking at each other, the fact that squiggles on a page are somehow related to concrete concepts, etc.) By the time this is all resolved, the child has missed out on lots of critical language exposure, and in some cases, impacts their ability to acquire a first language normally. This also makes sense - hearing children are surrounded by rich language input all day every day, more than a deaf child will ever have access to. Not only do the majority of people in the deaf child's life not use an accessible language, but even deaf children of deaf parents aren't able to see how their parents talk to each other in the other room, something a hearing child takes for granted.\n\nSo basically, yes, under the circumstances you described and under most circumstances, a deaf person can become bilingual (many deaf people are already bilingual in a signed and spoken language.) However, if they fail to adequately acquire a first language, second language acquisition can be difficult or impossible. As a side note, one of my former sign language teachers was fluent in five signed languages and two spoken languages."
]
}
|
[] |
[] |
[
[]
] |
|
1hptr6
|
how did the u.s., a country only a few centuries old, become the world's largest economy so quickly?
|
Middle Eastern countries produce more oil, Japan has a better reputation for electronics, cars, etc., and China is known for cheaper manufacturing (although this has only become true relatively recently). What does the U.S. produce that makes its economy so huge? Does it have an abundance of natural resources that no other country does? Is it a combination of many different factors? If so, what are the biggest, most relevant ones?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1hptr6/eli5_how_did_the_us_a_country_only_a_few/
|
{
"a_id": [
"cawq2fs",
"cax2pge"
],
"score": [
56,
8
],
"text": [
"You've been somewhat misinformed. \n\n[The US is the worlds third largest producer of oil, behind Saudi Arabia and Russia](_URL_5_), as well as the second largest producer of coal and natural gas.\n\nThe US auto industry has been the largest in the world since the invention of the car, and it's only fairly recently that china has been outproducing the US, though their cars have much worse reputations, and have difficulty reaching foreign markets. \n\n[In fact, The US had been the largest manufacturing country in the world for over a century, until china over took them in 2010](_URL_2_)\n\nAs for natural resources, The US has the most [arable land](_URL_4_), [#1 in timber](_URL_3_), [is #2 in copper](_URL_7_) [# 3 in gold](_URL_1_), as well as a [few other things](_URL_6_)\n\nBut the US has a few huge advantages over other countries. One, it's massive population. The best resource a country can have is people, everything else is secondary. The reason China has been able to catch up to the US economy is by leveraging it's massive population, and if they're careful, it's what will allow their economy to double ours in the next 100 years. \n\nTwo, it's isolation from the rest of the world. While Europe was conquering Africa, robbing China blind, and extracting every cent from India, the US was left on it's own to grow as they wished. While Europe was blowing it's self up, both times, the US saw approximately 0 fighting on it's homeland, leaving all of it's infrastructure and production capabilities intact while European factories and roads were all destroyed. When the wars were over, the first thing Europeans would do is buy American goods. \n\nThree, technology. I won't go too into it, but read up on [Big Science](_URL_0_). Essentially, WWII made it very clear how important technology was, and the US starting funding it large-scale. \n\nFour, The US is really good at exporting it's culture. When was the last time you saw an Indian movie? They make thousands every year. Or a french one? they're very well respected by movie critics. Or heard a German song? or read an Italian book? Or ate at a Spanish chain restaurant? Probably not very often, but anyone in Germany can go see the latest Hollywood batman movie, buy a Lady Gaga cd, and grab some McDonalds on the way home. Not many countries can do that that well. ",
"ITT, no mention of how slavery, war or the extortion of it's people has thus far helped the economy. One pretty good answer but it is far too pc. I'm not saying that the reason the u.s does so well is all bad, but it certainly isn't all rainbows and butterflies either. "
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Big_Science",
"http://en.wikipedia.org/wiki/List_of_countries_by_gold_production",
"http://en.mercopress.com/2011/03/15/china-became-world-s-top-manufacturing-nation-ending-110-year-us-leadership",
"http://www.mapsofworld.com/world-top-ten/countries-with-most-timber-producing-countries.html",
"https://en.wikipedia.org/wiki/Land_use_statistics_by_country",
"https://en.wikipedia.org/wiki/List_of_countries_by_oil_production",
"http://www.indexmundi.com/united_states/natural_resources.html",
"http://en.wikipedia.org/wiki/List_of_countries_by_copper_production"
],
[]
] |
|
8s03db
|
why does honey form small coils when it's being poured?
|
Have you ever noticed how some honey containers will cause honey to make small coils when you're pouring it out? It seems that it happens most prominently when there is a thinner flow.
Thanks!
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8s03db/eli5_why_does_honey_form_small_coils_when_its/
|
{
"a_id": [
"e0vgzut"
],
"score": [
4
],
"text": [
"Destin from Smarter Every Day has a video on this: _URL_0_"
]
}
|
[] |
[] |
[
[
"https://youtube.com/watch?v=zz5lGkDdk78"
]
] |
|
295tf6
|
Is there anything saltier than table salt?
|
I know there are ingredients sweeter than sugar, but is there anything saltier than regular table salt ?
|
askscience
|
http://www.reddit.com/r/askscience/comments/295tf6/is_there_anything_saltier_than_table_salt/
|
{
"a_id": [
"cihsmqb",
"cihsq5k"
],
"score": [
4,
3
],
"text": [
"Well, how strongly you taste something is mostly determined by how \"well-fitting\" molecules of the substance are to your tastebud receptors. For sodium, there are specific receptors that have evolved to strongly fit Na+, termed ENaC. Though there are other receptors that are taste ions from salt more broadly (K+, NH4+, etc), I think the implication is that since there are specific ones for Na+, we will taste the Na+ part of NaCl more strongly than any other salt.\n\nCheck the paper [here](_URL_0_) for more details.",
"Since table salt is NaCl (with a little Iodine usually) and a \"real\" salt is pretty much just a 1:1 ionic bond to a halogen, there are a number of other things that would be just about as \"salty\" as salt. However, the human tongue's supposed salt receptor really only reacts with two alkali metals: Sodium and Lithium.\n\nBut that right there is the key. The tongue recognizes \"saltiness\" by absorbing the alkali metals (namely Sodium) because it needs them for all the Sodium Potassium pumps/channels. Thus it doesn't need to be a true salt (halogen + alkali) to register in the body as salty.\n\nSo since the only metals that really work when binding to the tongue are Li and Na, and Na is more reactive, we would want to find a simple chemical that releases as much aqueous Na per unit measurement when dissolved at room temperature. Pulling a chemical out of my ass I'll guess Na2_S because it has two Sodium ions when dissolved. Other than that free Na +1 poured right on the tongue might work, although neither method should be done because, well, it's dangerous to your health. Table salt is already REALLY salty tasting.\n\n"
]
}
|
[] |
[] |
[
[
"http://ajpgi.physiology.org/content/291/6/G1005"
],
[]
] |
|
70pz3i
|
What did being wealthy look like in the bronze age?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/70pz3i/what_did_being_wealthy_look_like_in_the_bronze_age/
|
{
"a_id": [
"dn5ibf5",
"dn6kzip"
],
"score": [
954,
2
],
"text": [
"This is a pretty broad question both geographically and chronologically, so I'll limit my answer to Middle and New Kingdom Egypt and can provide comparisons with other regions and time periods if necessary.\n\nTurning first to houses, the site of Lahun provides examples of houses of different sizes and levels of complexity. Lahun was founded as a pyramid town of Senusret II and flourished during the Middle Kingdom; a town plan can be seen [here](_URL_16_). Domestic space at Lahun consists of the \"mayor's house\" on the acropolis, five northern mansions, three southern mansions, eastern housing, and western housing. The latter two were fairly simple compared to the mansions; comparative floor plans [can be seen here](_URL_24_). A mansion at Lahun consisted of a reception hall, sleeping quarters, an office, servants' quarters, and workshops and food preparation areas. Egyptian tomb models depict many of the parts of the house of an elite Egyptian family, including the [granary](_URL_25_), [butchery](_URL_7_), [livestock pens](_URL_13_), [weaving workshop](_URL_9_), [baking and brewing facilities](_URL_11_), and [carpentry workshop](_URL_3_). A [garden and pool](_URL_19_) formed the center of the house. Finally, the exterior of the house contained porticoes used for public appearances and [cattle counts](_URL_5_). \n\nWealthy Egyptians had many different ways to entertain themselves. [Banquets](_URL_8_) were quite popular, and [musicians and dancers](_URL_10_) as well as [harpists and storytellers](_URL_14_) were hired to entertain guests. To relax and escape the heat, wealthy Egyptians often took boat excursions into the marshes for [fishing and fowling](_URL_2_). These [boating excursions](_URL_17_) often involved numerous people. \n\nAncient Egypt had several grades of linen, including \"royal linen\" (*sšr nsw*) and \"fine linen\" (*šmat nfrt*). Elite clothing was therefore distinguished from the clothing of commoners by quality as much as complexity. For a comparison of the clothing worn by commoners and the clothing of the Egyptian elite, see this [New Kingdom tomb painting](_URL_27_); note the quality of the sheer linen worn by Nakht, the tomb owner. Egyptian male nobles sometimes received the [gold of honor](_URL_6_) from the king as a sign of favor, and elite Egyptian women wore elaborate [jewelry](_URL_21_) and [wigs](_URL_20_) as a mark of their status. The elite also used [makeup](_URL_15_) and [perfume](_URL_23_), which was indicated in art as a cone atop the head.\n\nMany, but certainly not all, wealthy Egyptians were literate. The [Heqanakht papyri](_URL_22_) provide a rare glimpse of literacy within a middle class family during the Middle Kingdom. The papyri, written in a lovely hieratic hand, are the remnants of a correspondence between a priest and his family. Heqanakht seems to have been a rather irritable fellow, and his letters are full of indignation and criticisms on how the household is being run in his absence. One of his sons, for example, seems to have been harassing his father's new wife.\n\n > As this man lives for me - it's Ip l'm referring to - whoever shall make any sexual advance against my new wife, he is against me and I against him. Since this is my new wife and it is known how a man's new wife should be helped, so as for whoever shall help her, it's the same as helping me. Would even one of you be patient if his wife has been denounced to him? So should I be patient! How can I remain with you in the same community if you won't respect my new wife for my sake? \n\nEgyptian status was in many ways tied to literacy, and the \"Satire of the Trades\" notes the benefits of being a scribe while denigrating other professions.\n\n > See, there's no profession without a boss, \n\n > Except for the scribe; he is the boss. \n\n > Hence if you know writing,\n\n > It will do better for you\n\n > Than those professions I've set before you,\n\n > Each more wretched than the other.\n\nElite Egyptian men were responsible for producing and copying almost all surviving Egyptian literature, such as the [library of Qenherkhopeshef](_URL_0_) at Deir el-Medina. \n\nWhen wealthy Egyptians died, they were buried in elaborate tombs that they prepared before their death. Burials typically consisted of a [rock-cut tomb](_URL_26_), a [painted coffin](_URL_4_), and [canopic jars](_URL_12_) for internal organs. Elite burials of the 18th Dynasty often included [food and furniture](_URL_18_) as well. Tombs often contained lengthy biographies outlining the career of the tomb owner. For example, the tomb of Weni contained an autobiography shedding light on Old Kingdom history. An excerpt:\n\n > When there was a secret charge in the royal harem against Queen Weret-yamtes, his majesty made me go in to hear (it) alone. No chief judge and vizier, no official was there, only I alone; because I was worthy, because I was rooted in his majesty's heart; because his majesty had filled his heart with me. Only I put (it) in writing together with one other senior warden of Nekhen, while my rank was (only) that of overseer of royal tenants. Never before had one like me heard a secret of the king's harem; but his majesty made me hear it, because I was worthy in his majesty's heart beyond any official of his, beyond any noble of his, beyond any servant of his.\n\n > When his majesty took action against the Asiatic Sand-dwellers, his majesty made an army of many tens of thousands from all of Upper Egypt: from Yebu in the south to Medenyt in the north; from Lower Egypt: from all of the Two-Sides-of-the-Houses and from Sedjer and Khen-sedjru; and from lrtjet-Nubians, Medja-Nubuians, Yam-Nubians, Wawat-Nubians, Kaau-Nubians; and from Tjemeh-land.\n\n > His majesty sent me at the head of this army, there being counts, royal seal-bearers, sole companions of the palace, chieftains and mayors of towns of Upper and Lower Egypt, companions, scout-leaders, chief priests of Upper and Lower Egypt, and chief district officials at the head of the troops of Upper and Lower Egypt, from the villages and towns that they governed and from the Nubians of those foreign lands. I was the one who commanded them - while my rank was that of overseer of royal tenants - because of my rectitude, so that no one attacked his fellow, so that no one seized a loaf or sandals from a traveler, so that no one took a cloth from any town, so that no one took a goat from anyone...\n\nFor further reading, I highly recommend [*High Culture and Experience in Ancient Egypt*](_URL_1_) by John Baines.\n\n\n\n\n\n",
"Related question: would the Iliad and Odyssey provide a partial answer to OP's question? The events take place during the Bronze Age in Greece, and the main characters are wealthy people. The issue that remains is how accurate those depictions are."
]
}
|
[] |
[] |
[
[
"http://www.ucl.ac.uk/museums-static/digitalegypt/writing/library/dem.html",
"https://www.amazon.com/Culture-Experience-Ancient-Studies-Egyptology/dp/1845533003",
"http://www.irequireart.com/i/artwork/710-image-1600-1600-fit.jpg",
"http://www.touregypt.net/images/touregypt/workshop.jpg",
"http://images.metmuseum.org/CRDImages/eg/original/DP342608.jpg",
"http://media.gettyimages.com/photos/egyptian-civilization-middle-kingdom-xi-dynasty-wooden-model-the-of-picture-id122213982",
"https://scontent-sea1-1.cdninstagram.com/t51.2885-15/s480x480/e35/16583620_1706958369334185_1778633810829639680_n.jpg?ig_cache_key=MTQ0ODg2NzM0ODg3NzgwNTQ4NQ%3D%3D.2",
"http://images.metmuseum.org/CRDImages/eg/original/DP351556.jpg",
"http://www.top10n.net/wp-content/uploads/2015/08/Top-10-Most-Famous-Ancient-Egyptian-Feasts-.gif",
"http://www.eloquentpeasant.com/wp-content/uploads/2011/01/weaving-1024x658.jpg",
"https://i.pinimg.com/originals/67/c4/ee/67c4ee43c72c651c4175a342790fc77f.jpg",
"https://3.bp.blogspot.com/-U732jCS5CAY/WbDR1UH9pwI/AAAAAAAAJ8w/GQ6O80uRWuYexzBiOZURoDqW1bNnvMz9ACLcBGAs/s1600/AncientEgyptianBakeryBrewery.jpg",
"https://cowofgold.wikispaces.com/file/view/ps317224_lll.jpg/151612101/299x182/ps317224_lll.jpg",
"http://images.metmuseum.org/CRDImages/eg/original/DT234927.jpg",
"http://www.touregypt.net/images/touregypt/music8.jpg",
"https://hairanddeathinancientegypt.files.wordpress.com/2014/07/woman-with-mirror-papyrus-of-torino-ancient-egypt-e1405099505989.jpg?w=300&h=201",
"http://www.ucl.ac.uk/museums-static/digitalegypt/lahun/townplan.gif",
"http://maritimehistorypodcast.com/wp-content/uploads/2014/11/DT1529.jpg",
"http://www.deirelmedina.com/lenka/TurinKha.html",
"https://www.brown.edu/Departments/Joukowsky_Institute/courses/historyofegyptone10/files/11990382.jpg",
"http://solarey.net/wp-content/uploads/2016/08/Princess-sit-hathor-yunet-01-e1471790896857.jpg",
"http://www.metmuseum.org/toah/images/hb/hb_16.1.3_av2.jpg",
"http://images.metmuseum.org/CRDImages/eg/web-large/DP351757.jpg",
"http://www.ancientegyptonline.co.uk/images/incensecone.jpg",
"http://slideplayer.com/slide/9481022/29/images/5/Plan+of+the+Northern+Section+of+Kahun,+1880-1874+BCE,+modern+el-Lahun.jpg",
"https://traveltoeat.com/wp-content/uploads/2014/10/wpid-Photo-201410180837459.jpg",
"https://describingegypt.com/tours/sennedjem",
"https://upload.wikimedia.org/wikipedia/commons/3/3d/Tomb_of_Nakht_%282%29.jpg"
],
[]
] |
||
6km1it
|
why is plastic surgery "plastic"?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6km1it/eli5_why_is_plastic_surgery_plastic/
|
{
"a_id": [
"djn30m5",
"djn311w",
"djn3t07"
],
"score": [
9,
36,
10
],
"text": [
"It's not plastic - the material - itself. It's the fact that the body is \"plastic\" - it is modeled. Simple as that.",
"\"Plastic\" means \"capable of being molded or shaped into forms\". The substance called \"plastic\" was named after this property, and the surgery term uses the first meaning.",
"It comes from the English word \"plasticity\" , which means the capacity to take up a shape and to change its shape.\n\nWhat we common call \"plastic\", is just a short way to say \"Plastic materials\" , because these can be given lots of shapes.\n\nPlastic surgery is plastic, because you are actually changing the shape of the 'flesh'."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
imiit
|
Is Carl Jung's work relevant?
|
I know there is an r/psychology, but it's actually that subreddit that brings me here. I keep seeing posts and comments praising Jung and his work, but as far as I can tell it's closer to new age mysticism (although that would make him ahead of his time would it?) than actual psychology.
So what say you askscience? Does Jung's work deserve attention beyond its historical context?
|
askscience
|
http://www.reddit.com/r/askscience/comments/imiit/is_carl_jungs_work_relevant/
|
{
"a_id": [
"c24zdor",
"c250267"
],
"score": [
4,
2
],
"text": [
"The psychiatrists I know don't think much of Jung (YMMV). However, I would point you to [Joseph Campbell](_URL_0_). His work is heavily derived from Jung's and is considered quite relevant in fields like cultural anthropology. In fact more people learn about Jung's ideas from exposure to Campbell than from reading Jung. ",
"I think it depends upon 'relevant to whom'. There are theoretical foundations underpinning many different areas: clinical psych, cognition, education, human development, etc. Each researcher *should* have some theorist whose underpinnings they use when researching or explaining phenomena. While some would say that he's a crackpot, others (such as those in counseling, etc.) may say that his ideas still have merit. Sure, there are many things that we now know that may discredit some of his ideas, but some were very foundational in other ways.\n\nIn the words of Santayana: \"We must welcome the future, remembering that soon it will be the past; and we must respect the past, remembering that it was once all that was humanly possible.\""
]
}
|
[] |
[] |
[
[
"http://www.jcf.org/"
],
[]
] |
|
8wjd2x
|
AskHistorians Podcast 115 - The Friends They Loathed - Quaker Religion and Persecution in the American Revolution
|
[**Episode 115 is up!**](_URL_2_/askhistorians-podcast-115-the-friends-they-loathed-quaker-religion-and-persecution-in-the-american-revolution)
The [AskHistorians Podcast](_URL_2_) is a project that highlights the users and answers that have helped make r/AskHistorians one of the largest history discussion forums on the internet. You can subscribe to us via [iTunes](_URL_0_), [Stitcher](_URL_9_), or [RSS](_URL_2_/rss), and now on [YouTube](_URL_11_) and [Google Play](_URL_5_). You can also catch the latest episodes on [SoundCloud](_URL_1_). If there is another index you'd like the cast listed on, let me know!
**This Episode:**
Today we talk with /u/UncoveredHistory, better known as Jason Aglietti. He is a public librarian in Baltimore and he just finished his Master’s thesis from University of Maryland Baltimore County, where he wrote and defended his thesis The Friends They Loathed: The Persecution of Maryland Quakers During the Revolutionary War.
Jason will tell us all about the lives of the Quakers in the American colonies from their founding to their persecution in the revolutionary war. This is NOT the history you usually hear about the revolutionary war, and Jason gives us a lot of new things to think about!
Finding The Maryland 400, the history project Jason worked on and talks about [can be found here](_URL_7_). Jason's blog is [here](_URL_10_).
**Questions? Comments?**
If you want more specific recommendations for sources or have any follow-up questions, feel free to ask them here! Also feel free to leave any feedback on the format and so on.
If you like the podcast, please rate and review us on [iTunes](_URL_0_).
Thanks all!
[Previous episode and discussion](_URL_4_).
Next Episode: /u/thucydideswasawesome is back!
Want to support the Podcast? Help keep history interesting through the [AskHistorians Patreon](_URL_3_).
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/8wjd2x/askhistorians_podcast_115_the_friends_they/
|
{
"a_id": [
"e1vwo3j",
"e1w2yoa",
"e27y18u"
],
"score": [
4,
4,
2
],
"text": [
"Thank you as always to the incredible podcast team and all of you who participate on it! Looking forward to sitting down and having a listen. ",
"I’m happy to answer any questions!",
"This was really interesting. You mentioned briefly that by the 1760s, Quaker dominance in Pennsylvania was declining. Can you tell us anything more about the changing religious demographics of Pennsylvania in the mid-to-late 18th century? Was this shift due mostly to immigration or because people were converting to other religious communities?"
]
}
|
[] |
[
"https://itunes.apple.com/us/podcast/the-askhistorians-podcast/id812302476?mt=2&ign-mpt=uo%3D8",
"https://soundcloud.com/user679855208",
"http://askhistorians.libsyn.com",
"https://www.patreon.com/askhistorians",
"https://www.reddit.com/r/AskHistorians/comments/8pk9ip/askhistorians_podcast_113_the_history_of_medicine/",
"https://play.google.com/music/podcasts/portal#p:id=playpodcast/series&a=100831514",
"http://askhistorians.libsyn.com/rss",
"https://msamaryland400.wordpress.com/",
"http://askhistorians.libsyn.com/askhistorians-podcast-115-the-friends-they-loathed-quaker-religion-and-persecution-in-the-american-revolution",
"http://www.stitcher.com/podcast/tas-stacey/the-askhistorians-podcast",
"https://jasonaglietti.wordpress.com/",
"https://www.youtube.com/channel/UCJudPwztZyg2BQjhetw_bww"
] |
[
[],
[],
[]
] |
|
1dt203
|
A couple questions about redshift and relativity.
|
Imagine that we have a probe that is capable of two things. It can measure the redshift of photons that come from any direction, and it can maintain relativistic speeds. If i were to set this probe into orbit around the sun a couple miles from the surface, it would have to travel very very fast to maintain its orbit (I think it escape velocity is around 600000m/s at surface). Now, would the probe observe a net redshift from the sun? Or would the redshift from behind the probe be equaled out by the observed blueshift from the front?
If the same probe was put on a straight path between our sun and another star and accelerated to nearly the speed of light toward the other star, would there be a point in that journey where neither light source is in the visible spectrum from the probe's point of view? If we somehow find a way to accelerate large objects to the speed of light, wouldn't that essentially mean any photon incident on the object from the direction of travel would be shifted into gamma rays and cause structural damage to the object?
Sorry for so many questions. I just want to make sure I have a solid understanding of "things".
|
askscience
|
http://www.reddit.com/r/askscience/comments/1dt203/a_couple_questions_about_redshift_and_relativity/
|
{
"a_id": [
"c9tkxbt",
"c9tl2vh"
],
"score": [
3,
5
],
"text": [
"I don't think you need relativity. Non-relativistic Doppler effect alone tells you that the spectrum of the parts of the sun in front of the probe will be blue-shifted, and the spectrum of the parts behind it red-shifted.\n\nBoth the Sun and nearby stars produce not only visible light, but also ultraviolet and infrared. If visible light is blue-shifted, infrared will be visible, and if it is red-shifted, ultraviolet will be visible.\n\nIf you accelerate something to nearly light speed, cosmic microwave background radiation will be blue-shifted to gamma rays, and reacting with the protons in the probe produce pi-mesons, which will take energy away from the probe. The speed where it happens is called the GZK limit.",
"I don't know if I follow your first scenario very well, but I will try my best to answer what I can. \n\nFirst off, there is no system which can \"measure redshift.\" All you can do is measure the frequency. Now, there are times you can use that frequency and determine the amount of red shift if you know what frequencies of light you are looking at (for instance, find where the absorption lines are looking at the Sun, know that they are actually helium and hydrogen lines, and calculate). However, you can never directly measure red shift. \n\nOk, so now to your question about heading towards a distant star. Yes, if you traveled fast enough, the light coming towards you would be blue shifted to the gamma range, and all of the negatives of gamma radiation would affect you unless you protected yourself from them. That also means that if you traveled at an object quickly enough, it could become invisible to you, unless it was emitting long enough wavelength (so a low heat perhaps?) that was blue-shifted to the visible spectrum. \n\nThe reverse is also true, you could travel away from the Sun quickly enough so that its light would be red-shifted away from you and thus you could no longer see it. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
37q4oi
|
how do you train messenger birds?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/37q4oi/eli5_how_do_you_train_messenger_birds/
|
{
"a_id": [
"crovgn7"
],
"score": [
3
],
"text": [
"Messenger birds can't deliver messages to arbitrary locations. They're birds (generally pigeons) that have a homing instinct that helps them return to their roost over long distances. So you raise one at your location, release them from further and further away from their roost to help them learn the area, and then give them to people you want to be able to send you messages.\n\nLikewise, if you want to be able to send someone messages, you have to have one of their pigeons delivered to you."
]
}
|
[] |
[] |
[
[]
] |
||
2fnwq6
|
why is it illegal to record a phone call without the person's consent?
|
In Michigan, I am breaking the law if I record a conversation without the consent of all parties involved. How is this legal? Am I not entitled to protect myself by creating concrete evidence?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2fnwq6/eli5_why_is_it_illegal_to_record_a_phone_call/
|
{
"a_id": [
"ckb0inq",
"ckb1aas"
],
"score": [
2,
8
],
"text": [
"Because there is a certain level of expect privacy when on the phone having a conversation from the privacy of your own home. \n\nOr at least this is the thought process when the laws were originally written. Obviously the vast use of cell phones have changed that, but many states still keep these laws. ",
"You are mistaken. Michigan courts have said it is eavesdropping for anyone not a part of the conversation to record the call. Federal law requires only one party on the call know that it is being recorded.\n\nBack in the old days, there were multi-party phone lines, which made it cheaper for people living in rural areas to get phone service. It meant that many people 'shared' a single phone line. If you wanted to use the phone, you would need to check and make sure someone else wasn't already using it. You could also listen to a conversation taking place by quietly picking up any phone in the loop. That behavior was inconsiderate and rude to your neighbors, and made illegal to protect persons from gossip or blackmail.\n\n_URL_0_"
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Telephone_recording_laws#United_States"
]
] |
|
1nmyx0
|
Did Ancient Greece ever have sectarian conflicts? What were the major religious lines of division?
|
I'm wondering if Ancient Greece ever saw sectarian conflict on the scale that we have in recent(ish) history - I.e Catholics v. Protestants or Sunni v. Shia - and if so, what were the major areas of division? Or did everyone largely get along in an inclusive polytheistic system?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1nmyx0/did_ancient_greece_ever_have_sectarian_conflicts/
|
{
"a_id": [
"cckbnjm"
],
"score": [
2
],
"text": [
"By Sectarian, I’m taking from your question that you mean religious and not territorial sectarian violence. Because the Greeks had a whole lot of territorial violence that could be defined as Sectarian. Religions could be used as a spark for a conflict but there wasn’t constant sectarian religious warfare like the Catholics/IRA v. England, Catholics v. Protestants, Muslim v. Christian,Muslim v. Hindu,etc...\n\n While we rattle off names like Zeus,Ares,Artemis,Hera,etc… the various city-states had their own interpretations of each usually. The Idea of Ares in Sparta would be different than the one in Athens or Argo. They’d also often have their own holidays/festivals/holy days. The Spartans were famously late for the Battle of Marathon because they had a religious observance(The Carnea festival honoring Apollo) and couldn’t march until it was completed. Athens didn’t wasn’t beholden to the Carnea so they marched to Marathon to meet the Persians.\n\nAlso, cities and areas would have their own preferred gods like Athena and Athens, Helios for Rhodes,etc.. As to them fighting over their various interpretations, it was never a primary reason. It may have been thrown out as a secondary reason but the Greek City-States fought amongst themselves over the normal things: Land, Supplies,Money or Insults.\n\nI think a big reason for a lack of large-scale religious sectarian violence is that there were just so many different religions,cults, mystery cults,etc… floating around Greece. The island of Delos was a major port for trading so it came in contact with the levant, north Africa, Italy,etc… It had Greek religious temples, a temple to the Philistine god Baal and even a synagogue. It’d be real hard to fight solely from a religious sectarian view when your neighbors,family members,etc.. have different religions. It’d be exhausting."
]
}
|
[] |
[] |
[
[]
] |
|
4d4u0i
|
How did scientists figure out that the mantis shrimp can see 12 different wavelengths if humans can only see three?
|
askscience
|
https://www.reddit.com/r/askscience/comments/4d4u0i/how_did_scientists_figure_out_that_the_mantis/
|
{
"a_id": [
"d1oy25j"
],
"score": [
5
],
"text": [
"They extracted the proteins from the retina of the Mantis Shrimp. We have three types of cone cells in our eyes that are activated when differing wavelengths of light hit them. The mantis shrimp is the same, except they found up to 12 different types of detectors; each for a slightly different wavelength.\n\nThe real question is: with a visual cortex so small, can the Shrimp really perceive all the beauty he could see? Or is he limited by the small size and power of his brain and able to only really see one or two wavelengths at a time?"
]
}
|
[] |
[] |
[
[]
] |
||
33cfy7
|
can we pump greenhouse gases into space?
|
Out of the greenhouse, so to speak. If not, why not. If it is feasible, why haven't we yet?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/33cfy7/eli5_can_we_pump_greenhouse_gases_into_space/
|
{
"a_id": [
"cqjjca5",
"cqjjesk",
"cqjjjcw"
],
"score": [
3,
2,
4
],
"text": [
"The boundary between our atmosphere and space is called the [Kármán line](_URL_0_) and lays at a height of 62 miles. It's not possible to build a 62 mile high chimney with current technology. even at that height the gasses would probably fall back down rather than dissipate.",
" > If not, why not. \n\nThe only way we know to get it into space would be to literally load it onto rockets and launch them. The cost of this would be astronomical and we would not be able to keep up with how quickly we produce them.",
"No. None of us have the money, very few of us have the technology.\n\n**Problem #1:** Sorting out the \"bad gases\" from the \"good gases\". It's easy to verify those gases are present, but difficult to collect amounts of just that gas from the atmosphere in any reasonable amount. Most production of greenhouse gases for industrial use is done by making that gas with a chemical reaction.\n\n**Problem #2:** Pumping them out of the atmosphere. To make any reasonable dent in global warming, modern estimates usually figure a few *million tons* of greenhouse gas need to go. In order to get them into space, you have to somehow transport all those millions of tons straight up. Pressure pumping alone won't work: you would need a pipe that goes straight up out of the atmosphere. Google the space elevator problem for why this is problematic.\n\n**Problem #3:** You gotta keep all of it up there. Figuring out where to put all that gas would be difficult enough: you can't keep it in orbit, because it would pose a serious risk to spacecraft. That means that you are already transporting/piping this gas some 384000 km away.\n\n\n\nSo tl;dr: No we can't, it's way too hard to do.\n\nEDIT: Some formatting"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/K%C3%A1rm%C3%A1n_line"
],
[],
[]
] |
|
3x0brs
|
If you're breed into a war driven society like the Spartans, Mongols, Romans, etc. Is it a highly likely chance the soldiers still experience PTSD.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3x0brs/if_youre_breed_into_a_war_driven_society_like_the/
|
{
"a_id": [
"cy0f372"
],
"score": [
2
],
"text": [
"Insofar as PTSD is the result of neurological changes due to overexposure to traumatic situations, there is no reason why conditioning and training should make anyone less susceptible to it. Arguably the training itself, depending on the methods used, could become a cause of PTSD in itself.\n\nIn any case, I'm not sure to what extent the societies you mention were \"war driven\". Recent work by Stephen Hodkinson has shown that Sparta, for one, was not a militaristic society at all. It did not even have a military. Its social conditioning was focused on fostering obedience and endurance, and the outward features of its culture were intended to minimise and hide differences of wealth and status within the citizen body. The purpose of this entire system was not to create perfect soldiers, but to create a perfectly stable society, in which neither the destitution of the common people nor the rivalries of the elite would lead to an overthrow of the established political and legal institutions, as it did everywhere else in Greece on a regular basis. Sparta was not a military powerhouse but an elaborate and remarkably successful experiment in social engineering.\n\nThe Roman approach to warfare became more organised and disciplined during the mid-Republic, but I doubt the average Roman citizen would regard himself as bred for war. Most of them were farmers and labourers who were called to arms only at need. The rise of the professional army went hand in hand with the release of ordinary citizens from military duties, allowing them to focus entirely on their normal everyday activities as war became the business of those who chose a career in it."
]
}
|
[] |
[] |
[
[]
] |
||
dzvv6v
|
dry shampoo
|
Kinda silly, I know.
But as a young male who has never had hair longer than 6 inches, I don't understand how or why one would use dry shampoo. I have always just washed my hair daily so I don't get how rubbing powder into your scalp will help in any way. I know that washing your hair daily removes oils that are beneficial for scalp health, so I assume it's a way to combat that. Or is it just a laziness thing? Both?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/dzvv6v/eli5_dry_shampoo/
|
{
"a_id": [
"f8ahiti",
"f8altt5"
],
"score": [
8,
2
],
"text": [
"Dry shampoo is basically a powder that absorbs hair oils. No, it's not just laziness. Washing hair every day can be bad for your scalp (not only does it remove oil, as you mentioned, but shampoo ingredients can be incredibly harsh. Styling hair can also be incredibly damaging. If your hair gets wet, it needs to be restyled. For all of these reasons, people may want to extend the time between shampoo washes. Doesn't mean they aren't showering). \n\nFor people with thicker hair, washing and letting your hair air dry can mean you have a wet head for *hours*. If I shower before bed, I wake up with still damp hair. If I braid it, it could be wet for over a day. And my hair isn't particularly long or thick. Someone with longer, thicker hair might need to wash their hair less often or else they will just *always* have wet hair. Which is awful. \n\n\nThe other reason people use dry shampoo is because they want the texture that it gives hair. It might make their hair look fuller, more voluminous, or help hold certain styles better. Dirtier hair in general is seen as easier to style and dry shampoo can be a way for people to get the styling ease in still-clean hair. \n\nAlso, some people like the smell. \n\n\nThere are also dry conditioners for people who don't have greasy hair. They're basically anti static/frizz ingredients combined with dry conditioners to add shine and smooth flyaways.",
"They use it in hospitals and nursing homes for bed-bound patients. Easier than the showercap method."
]
}
|
[] |
[] |
[
[],
[]
] |
|
ux4k0
|
Why is belly fat different from other fat?
|
I have heard a few people claim that belly fat is harder on the body than fat in other areas of the body and that having high amounts of belly fat can result in higher risk of many health problems. Is there a chemical difference in the fat stored in different areas of out body? If not, what makes this fat less healthy? I've also heard that being under a lot of stress causes us to gain weight in the stomach area (I am reading Why Zebras Don't Get Ulcers by Dr. Saplosky), why is this so?
|
askscience
|
http://www.reddit.com/r/askscience/comments/ux4k0/why_is_belly_fat_different_from_other_fat/
|
{
"a_id": [
"c4zccss",
"c4zceik",
"c4zfkjo"
],
"score": [
2,
4,
3
],
"text": [
"The idea is that the 'belly' fat surrounds and puts pressure on your important organs as opposed to say leg fat. The fat itself is the same.\n\nNutrition/sports nerd - no references except info picked up at seminars.",
"abdominal fat is more correlated with insulin resistance. We don't know if the belly fat causes insulin resistance or if insulin resistance makes you more likely to store belly fat. \n\n_URL_0_",
"Additionally, your body \"likes\" to store fat around the belly, buttocks, and hips. This is because your torso moves the least. Think about it - if all your belly fat was instead located in your fingertips, it would take a lot more energy to move your hand around with the extra weight on it, as your arms and legs move quite often. Since your torso moves the least in comparison to your limbs, it is much more efficient for your body to store excess weight there."
]
}
|
[] |
[] |
[
[],
[
"http://diabetes.diabetesjournals.org/content/45/5/633.short"
],
[]
] |
|
tgkn1
|
Is it possible that Earth has had moons in the past and they were destroyed?
|
askscience
|
http://www.reddit.com/r/askscience/comments/tgkn1/is_it_possible_that_earth_has_had_moons_in_the/
|
{
"a_id": [
"c4mg9g3",
"c4mhoid",
"c4mhpxx",
"c4mi310"
],
"score": [
152,
10,
6,
3
],
"text": [
"Not only is it possible, but there is actually evidence suggesting the Earth did in fact used to have two moons: _URL_0_",
"The earth captures many small objects for short periods of time, making them transient moons of sorts. _URL_0_\n",
"There are objects in space which come close to being a second moon currently.\n\n_URL_0_",
"Before our moon formed, the ejecta from the impact would have been a very substantial ring around the earth.."
]
}
|
[] |
[] |
[
[
"http://www.nature.com/news/2011/110803/full/news.2011.456.html"
],
[
"http://www.universetoday.com/92453/how-many-moons-does-earth-have-2/"
],
[
"http://en.wikipedia.org/wiki/Other_moons_of_Earth#Quasi-satellites_and_Trojans"
],
[]
] |
||
h9re5
|
Power Transformer explosions in Ft. Worth, TX. What could cause this?
|
[_URL_0_](_URL_0_)
|
askscience
|
http://www.reddit.com/r/askscience/comments/h9re5/power_transformer_explosions_in_ft_worth_tx_what/
|
{
"a_id": [
"c1tonco",
"c1toso7",
"c1tr343"
],
"score": [
3,
3,
2
],
"text": [
"I actually just saw a lecture about this. The explosions are caused when the oil used as a coolant ignites. The thing has to fail prior to this happening, for instance by a component melting.",
"Well there's a lot of things that can cause a single transformer to fail. To have so many fail, I'd have to guess there was a pretty significant short somewhere and a circuit breaker failed to trip. Transformers are filled with an oil that both cools and prevents arcing. Transformers also produce enormous magnetic flux which can cause spot heating that can vaporize that oil, that can in turn cause the transformer to explode if the pressure isn't relieved. \n\nIf the transformer loses its oil, it can start arcing as air is more sensitive to dielectric breakdown than the transformer oil. Arcing can cause voltage spikes, which can damage other transformers.",
"ECE undergrad here. Once that much charge gets put into the grid it starts throwing breakers left and right. Eventually it has nowhere to go and starts breaking down the materials in the lines and overloading transformers. The excess charge would continue to bounce back and fourth along an isolated section of the grid for some time since the only place for the charge to go is into the surroundings as heat and light. Its no surprise that it took over a half hour for the action to calm down, since the excess charge could only escape in comparatively tiny, albeit violent, bursts."
]
}
|
[] |
[
"http://news.yahoo.com/s/yblog_localdallas/20110511/ts_yblog_localdallas/amazing-video-shows-transformers-exploding-in-fort-worth"
] |
[
[],
[],
[]
] |
|
6cqnyj
|
When PTSD was officially recognized as mental disorder by the American Psychiatric Association in 1980, were there a substantial amount of people that denied PTSD's existence/credibility? and why?
|
In recent years, there have been many issues where the public has debated on if an idea is credible science or pseudo-science. To keep this politically neutral I won't list any of the present issues, but we should have at least heard of them.
However, when PTSD was officially recognized as mental disorder by the American Psychiatric Association in 1980, were there a substantial amount of people denying PTSD's existence/credibility? I ask this because before PTSD was recognized, it seems like many people condescended and ignored people with shell shock, as it was called back then, as Virginia Woolf's *Mrs. Dalloway* shown. So when PTSD was diagnosed as a mental illness, did some people deny its status saying *"people don't have PTSD. They are just cowards!"* and how numerous were they?
I'm sorry if this post has some misconceptions about PTSD and its history. I was born in 1998 and most of what I know about PTSD comes from *The Legend of Korra* and [these](_URL_1_) two [posts.](_URL_0_)
Thanks in advance!
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/6cqnyj/when_ptsd_was_officially_recognized_as_mental/
|
{
"a_id": [
"dhxgqa6"
],
"score": [
4
],
"text": [
"The profession of clinical psychology in America actually came into being specifically because of soldiers suffering psychological distress as a result of their wartime experiences in World War II. In America during World War II, psychologists were seen as valuable by the U.S. military; of the ~4000 psychologists in a 1942 survey, about 25% were employed by the military. However, at this point, professional psychologists were either researchers or people who performed psychological testing or applied psychological principles in a broad sense. So, for example, a professional psychologist in the U.S. military might administer IQ tests or other suitability tests for the military, or might serve in advisory capacities on how to best increase the speed of production on factory lines (and so forth). Psychologists in 1942 weren't sitting in rooms with people talking about their problems. Instead, that was what psychiatrists - medical doctors specialising in mental illness - did.\n\nHowever, at the end of the war, there were 44,000 hospitalised veterans who were hospitalised for psychological reasons, presumably many of which had symptoms of what we'd now call post-traumatic stress disorder, though it wasn't called as such at the time. As a result - and because there just weren't enough psychiatrists to keep up with demand - in 1946, the VA set up clinical psychology training institutions at many major U.S. universities, who aimed to turn out graduates who could apply psychological theory to the art of therapy. \n\nIn general, the early clinical psychologists did not seem to spend much time arguing that their military psychiatric population had something like post-traumatic stress disorder which manifested differently in some people but was basically the same; a [very early 1946 paper by Abraham Luchins](_URL_0_), for example, trying out a group psychotherapy on his patients doesn't try to classify the disorder at all, or divide patients into different groups. That said, there's a ['War Bulletin' in a 1946 issue of the *Journal of Clinical Psychology*](_URL_1_) which lists a variety of different psychological conditions. In this war bulletin, the conditions that seem most like PTSD to me, judging by their descriptions, are divided into three conditions: 'transient personality reactions to acute or special stress', 'combat exhaustion', and 'acute situational maladjustment' (you can see the descriptions on the preview page on the link - they're obviously more general guides than the bullet point 'must have 6 or more'-style lists of the DSM-III from 1980). So clearly, at an institutional level in the U.S. military post World War II, there was an awareness that soldiers were being hospitalised for being unable to cope with the stress of their war experiences, and their re-integration into society. \n\nOne of the things to point out here, therefore, is that both psychologists and psychiatrists in the mid-20th century were generally unconcerned with diagnosis in the systematic way that we would now understand a diagnosis like PTSD. Instead, in general, there's much more focus on the cause of the symptoms rather than the broad pattern of symptoms. In American psychiatry this speaks to Freud's influence - he was less concerned with differentiating between anxiety and depression, and more concerned with the childhood issues that might be causing the symptoms. In clinical psychology, this likely spoke to the influence of behaviourism, an influential theory within psychology at the time, which argued that environmental stimuli played a large role in behaviour (and that, as a result, you could alter the environmental influences to alter the behaviour); clinical psychologists at this point, therefore, would in general focus more on the environmental stimuli connected to the upsetting emotional disturbances of soldiers, and less on the taxonomy of those disorders (PTSD treatment still does focus on identifying environmental stimuli that might be triggering flashbacks and the like).\n\nThe difference between 1946 and 1980 is that, within psychology, the influence of behaviourism waned, replaced by cognitivism (which argued that internal psychological modules that were often domain-specific played a large role in behaviour - cognitivism was much more inclined to seeing a *thing* called PTSD inside the mind than behaviourism was). Similarly, in psychiatry, the Freudian influence waned as psychiatrists became able to prescribe reasonably effective drugs for many disorders. Freudian ideas were replaced by more obviously medical ideas about psychiatric disorders being caused by, say, imbalances in brain chemicals like serotonin.\n\nThe DSM-III in 1980 - where post-traumatic stress disorder was first named as a specific disorder - was influential precisely because it reflected this new *medical* understanding amongst psychiatrists; it's fundamentally designed to look for constellations of symptoms that commonly occur together, so that psychiatrists can get a sense of what medications work best for what constellations of symptoms. It's safe to say that the disorders in the DSM-III do broadly reflect conventional wisdom amongst psychiatrists on what disorders were important to treat. These days, when new disorders are added to the DSM, it generally denotes awareness amongst psychiatrists that people are coming to them with distressing symptoms that do not neatly fit into existing categories.\n\nOf course, in an age where Freud's influence was waning but not entirely absent, not all psychiatrists were particularly happy about the medical slant of the DSM. Michael Trimble, writing a 1985 book chapter about the history of the PTSD concept, complains that 'post-traumatic neurosis' - which psychiatrists had been using previously to the DSM-III - is a perfectly fine term that the compilers of the DSM-III had avoided because it was too Freudian in its implications. Nonetheless, while Trimble grumbles about the DSM-III concept of PTSD somewhat, he ultimately thinks that the PTSD diagnosis is a good thing, because it means that there will be wider recognition that there are sometimes long delays between traumatic events and PTSD symptoms, and so sufferers will be more widely able to get treatment and insurance funding for that treatment - the DSM-III diagnosis at least seems very scientific and medical.\n\nThe question of how the wider culture reacted to psychological disorders in general is almost another topic on its own - but there was a slow increase in how sympathetic wider Anglophone culture was towards people with psychiatric disorders which started in the 1960s. The hippie movement famously flouted society's expectations, and seemed to enjoy the use of brain-altering chemicals and thus had a certain degree of sympathy for other people who also flouted society's expectations because of altered brain chemistry, such as schizophrenics. Similarly, people in the hippie movment like John Lennon of the Beatles played a role in the popularity of psychological fads like primal scream therapy. In the 1970s, the therapy session was a common trope in, say, Woody Allen movies, and of course the 1975 movie *One Flew Over The Cuckoo's Nest* (based on a book originally written in the 1960s by Ken Kesey, a prominent figure in the hippie movement) portrayed the inmates of a psychiatric hospital in a more flattering light than psychiatric nurses, at least. By the 1990s, you had an influential, popular band like Nirvana with songs called things like 'Lithium' and 'I Hate Myself And I Want To Die', and much of the alternative movement in rock music wrestled with mental illnesses like depression, addiction, and anxiety; Chris Cornell of Soundgarden sadly comes to mind here as just one example of a prominent rock star of the era who was open about suffering from depression.\n\nI've taken the broader context route here rather than the specific answer to your question, but if there was pushback against the DSM-III amongst the public, it largely wasn't particular to DSM-III, but instead was about the medicalisation of mental illness in general. After all, acceptance of mental illness was associated with the hippie movement, and the hippies were not popular in some quarters of American society. For some people, mental illness is fundamentally not medical, because it's a disorder of a fundamentally non-material soul; they instead might believe mental illness as being fundamentally a sign that the person needs to accept Jesus into their life. And for people with right-wing authoritarian personalities, for whom strength is an important marker of a person, mental illness is often considered shameful because it's indicative of fundamental weakness. There was talk in the 1970s of 'post-Vietnam syndrome', whereby PTSD seemed to sometimes have an onset delayed by years, which previously hadn't been discussed much. There was also some speculation that 'post-Vietnam syndrome' might be related to the ambivalent-at-best way that soldiers who fought in Vietnam were often treated, in comparison to returned soldiers from previous wars. This certainly would have been a current in popular culture as the concept of PTSD was debated and codified in the DSM-III in the late seventies."
]
}
|
[] |
[
"https://redd.it/1ke4z8",
"https://www.reddit.com/r/AskHistorians/comments/63ujea/are_there_any_examples_of_ptsd_from_early_wars_or/"
] |
[
[
"http://onlinelibrary.wiley.com/doi/10.1002/1097-4679\\(194607\\)2:3%3C231::AID-JCLP2270020305%3E3.0.CO;2-K/full",
"http://onlinelibrary.wiley.com/doi/10.1002/1097-4679\\(194607\\)2:3%3C289::AID-JCLP2270020316%3E3.0.CO;2-O/full"
]
] |
|
2ydy17
|
Have we ever found a species which does no fit into the genetic "tree of life"?
|
A species that doesn't have any genetic connection to any other species basically. One which could have come to earth on an astroid possibly.
|
askscience
|
http://www.reddit.com/r/askscience/comments/2ydy17/have_we_ever_found_a_species_which_does_no_fit/
|
{
"a_id": [
"cp8nqo3",
"cp8nwzy",
"cp8qgui",
"cp9c35v"
],
"score": [
30,
9,
4,
2
],
"text": [
"The short answer to this is no. \n\nAll living things (I am excluding viruses from this discussion) are composed of cells surrounded by a membrane. They also all use DNA to store the instructions necessary to create proteins. Given these similarities, scientists have concluded that all life on Earth shares a common ancestor. It is important to note that this does not preclude the possibility that life *originated* elsewhere however. \n\nSince all life must perform many of the same functions (DNA replication, protein synthesis, metabolism), there is a subset of genes that all currently known living organisms possess. One of the most well-described of these genes is is the ribosomal RNA (or rRNA) gene. Similarities in this gene are used to determine the \"relatedness\" of two species since parts of it are not under selective pressure and can mutate at a (somewhat) predictable rate.\n\n",
"No. All species are assumed to have evolved here from common ancestors, anything that does not resemble life here would probably just be assumed to have ancestors which have not been discovered. You would need something completely strange to make the claim that it is not from this planet, like a species with a genetic structure without DNA or RNA. There are theories that life on Earth originated from extraterrestrial invasions, such as via asteroids, but all of this is largely theoretical and part of that theory is based on the fact we have not managed to create life from base elements in the laboratory with conditions similar to those present early in our planets history.\n\nIt's also worth mentioning that anything that arrived here would need to survive in similar habitats and would have similar systems to survive, meaning at first glance it would appear very similar to terrestrial species. For example, one reason everything uses oxygen is because early in our planets life, organisms known as cyanobacteria outcompeted other species of bacteria when they began producing oxygen, which was extremely toxic to most lifeforms. Now, we all love oxygen, because everything that did not quickly expired.",
"Nope. [But there's a new limb added now and again.](_URL_0_)",
"A universal common ancestor to all life on earth (Archaea, Bacteria, Eukarya) has been mathematically demonstrated as 10^2,860 times more probable than the closest competing theory (of 1,800 models tested), using genetic/protein sequence similarity.\n\nDouglas L. Theobald (2010) [\"A formal test of the theory of universal common ancestry\".](_URL_0_) *Nature*\n\nSo, no. "
]
}
|
[] |
[] |
[
[],
[],
[
"http://www.nature.com/news/sea-creatures-add-branch-to-tree-of-life-1.15833"
],
[
"http://www.nature.com/nature/journal/v465/n7295/full/nature09014.html"
]
] |
|
91tnu4
|
Does global warming on Earth affect the solar system at all?
|
[deleted]
|
askscience
|
https://www.reddit.com/r/askscience/comments/91tnu4/does_global_warming_on_earth_affect_the_solar/
|
{
"a_id": [
"e31sb5y"
],
"score": [
9
],
"text": [
"The Earth is part of the solar system.\n\nApart from that there is no relevant effect. The emission spectrum of the Earth shifts a tiny bit towards shorter wavelengths but that doesn't matter outside of Earth."
]
}
|
[] |
[] |
[
[]
] |
|
1h09dn
|
why won't flies and other insects react on sudden movements on the tv or computer monitors?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1h09dn/eli5_why_wont_flies_and_other_insects_react_on/
|
{
"a_id": [
"capmgtb",
"capnmom",
"capot4e",
"cappz35",
"capq1ts",
"capqo9l",
"capqove",
"capr3zp",
"capsjij",
"capsu4h"
],
"score": [
239,
71,
7,
11,
27,
6,
5,
3,
3,
2
],
"text": [
"I'm not sure about this, but I think flies and other insects move because of air moving around. As screens don't make air move, they ignore it.\nKind of relevant: _URL_0_",
"Flies react to even the slightest sudden air movement, so a moving picture won't startle them but your hand swatting at it will.",
"Put your eye up as close as you can to a TV screen while something is on. Looking at a single spot, you just see colors changing occasionally, you don't see any movement that close. On older screens, all you will see is Red, Green, and Blue pixels.\n\nAnother thought is that since flies are so small, time seems slower to them, so the colors changing will be even slower.",
"While not an insect, I've always found this really interesting. _URL_0_",
"Jumping spiders will track a mouse cursor.",
"/u/unidan \n\n/u/unidan \n\n/u/unidan \n\n",
"They can not look directly down or directly behind them. Tested it multiple times with glass tables and mosquito-nets (still air movement here).\nThat's why you can catch them with your hand, coming fast from low behind. Classic Ninja-party-trick ;)\n\nEdit: \"only dots changing colors/contrast\" also has truth in it, but doesn't explain mosquito-nets.",
"They do react to sudden movements on computer monitors. I've caused a bug to fly off of my screen before by waving my cursor over the area that it was settled on, multiple multiple times.",
"A lot of this is unbacked speculation. Try /r/askscience ",
"Probably because the sudden movements are really subtle up close. All the pixels are still red, blue, and green....yellow if you have a sharp aquos. But they're just seeing glowy disco floors."
]
}
|
[] |
[] |
[
[
"http://youtu.be/QH091zFHdQ0?t=3m"
],
[],
[],
[
"http://www.youtube.com/watch?v=IkIm0D7eZ-M"
],
[],
[],
[],
[],
[],
[]
] |
||
51syon
|
why do wireless headphones produce a less quality sound than wired ones?
|
I have been watching a lot of music fans upset about the new iphone because they don't want to be forced to use wireless headphones due to a loss in sound quality. What is the reasoning for why this would happen?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/51syon/eli5_why_do_wireless_headphones_produce_a_less/
|
{
"a_id": [
"d7ekx2j"
],
"score": [
2
],
"text": [
"Well to ELI5 (im sure someone will add a better technical information).....blue tooth technology used for wireless headphones simply transmits less information than wires. An analogy would be similar to comparing mp3 to cd quality audio.....mp3 simply has less of the information about the audio than CD which means something, somewhere is lost....."
]
}
|
[] |
[] |
[
[]
] |
|
12yv58
|
Are all solar systems formed within nebulae?
|
I've been trying to learn about astronomy on my own by reading everything I can get my hands on. When I find something I don't understand, I look that up next. I'm finding my curiosity seems to usually be a few steps ahead of what I'm able to read up on at the time.
So right now I'm trying to figure out, are there other ways for solar systems to form? Are all stellar nurseries HII regions? Is that even the right way to ask that? I might be confusing myself.
Sorry if any of these are stupid questions. I've read a lot of stuff and some times it's hard to keep it all straight!
*edit*
I know that Hubble has revealed over 150 proplyds within the Orion Nebula. Which I know is known as a stellar nursery. So I guess that got me trying to figure out if there are other ways suns, protoplanetary disks and therefore solar systems form.
|
askscience
|
http://www.reddit.com/r/askscience/comments/12yv58/are_all_solar_systems_formed_within_nebulae/
|
{
"a_id": [
"c6zbg9e"
],
"score": [
4
],
"text": [
"The largest stars (O and B type) form inside H II regions. Well, this might be the wrong way to think about it. It's the largest stars that actually *create* H II regions. Here's how it goes:\n\n1. Big cloud of (mostly) neutral hydrogen molecules\n\n2. Gravitational collapse\n\n3a. If the gas gets dense enough, the cloud core collapses into a big star, O or B type, that sends out high energy, highly ionizing photons that ionize the hydrogen in a region around the star, thus creating an H II region. Probably, not many planets form around these stars since the solar winds from the stars are extremely strong.\n\n3b. If the gas doesn't get very dense at the center, this process takes a little longer and we get a smaller (solar-type) star. Probably, these are the kinds of stars around which planets have time to form. \n\nHope this helps!"
]
}
|
[] |
[] |
[
[]
] |
|
3sekb6
|
why are the republican/democrat debates called debates? there's hardly any debating going on.
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3sekb6/eli5_why_are_the_republicandemocrat_debates/
|
{
"a_id": [
"cwwhqb4",
"cwwi48l"
],
"score": [
10,
6
],
"text": [
"They're mostly called debates to lend some gravitas to the situation.\n\nWhat they are these days, however, is joint press conferences.\n\nIt would be nice to have actual debates, but that would require politicians who are willing and able to think on their feet, and argue in defense of a position, rather than requiring an army of writers to create pre-prepared statements for them to memorize.\n\nThere aren't many who are willing or able to do that.",
"Once we get down to two candidates, the debates will become actual debates. You're right though, for now there's more masturbating than debating going on"
]
}
|
[] |
[] |
[
[],
[]
] |
|
ei21fz
|
Adult adoption seems to have been very common by the late Roman Republic; was this a political development, driven by social forces, or interpersonal ones (or something else)? Was it particular to the aristocratic class or common in general? Do we know how it developed?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/ei21fz/adult_adoption_seems_to_have_been_very_common_by/
|
{
"a_id": [
"fcn7xru"
],
"score": [
547
],
"text": [
"On his 62nd birthday, the emperor Hadrian - tormented by an illness that had crippled him and left him subject to bouts of murderous rage - convened a council of advisers at his bedside. Painfully shifting his dropsy-stiffened limbs, he delivered a short address about his succession plans. The historian Cassius Dio (who wrote nearly a century later) gives this version:\n\n\"I, my friends, have not been permitted by nature to have a son, but you have made it possible by legal enactment. Now there is this difference between the two methods — that a begotten son turns out to be whatever sort of person Heaven pleases, whereas one that is adopted a man takes to himself as the result of a deliberate selection. Thus by the process of nature a maimed and witless child is often given to a parent, but by process of selection one of sound body and sound mind is certain to be chosen. For this reason I formerly selected Lucius before all others...But since Heaven has bereft us of them, I have found as emperor for you in his place the man whom I now give you, one who is noble, mild, tractable, prudent, neither young enough to do anything reckless nor old enough to neglect aught, one who has been brought up according to the laws and one who has exercised authority in accordance with our traditions, so that he is not ignorant of any matters pertaining to the imperial office, but could handle them all effectively...\" (69.20)\n\nThus Hadrian announced his plans to adopt the man we know as Antoninus Pius, who would succeed him a few months later.\n\nRoman adoption might best be conceptualized as an oligarchic society's response to demographic realities. Thanks largely to cripplingly high rates of child mortality, many Roman families failed to produce a male heir. Adoption allowed a childless man to perpetuate his family- a concern to all classes, but most pressing and visible among the aristocracy. There were two legal forms of adoption - one for those who had previously paterfamilias of their own family, another for those who had been under the paternal power of another - but the upshot in each case was to make one man the legal son of another.\n\nLegal adoption seems to have developed fairly early - probably by the fourth century BCE. It was certainly well-established by the middle Republic, when the general and statesman Aemilius Paulus negotiated the adoption of two of his sons into prominent families:\n\n\"So then Aemilius, having divorced Papiria, took another wife; and when she had borne him two sons he kept these at home, but the sons of his former wife he introduced into the greatest houses and the most illustrious families, the elder into that of Fabius Maximus, who was five times consul, while the younger was adopted by the son of Scipio Africanus, his cousin, who gave him the name of Scipio.\" (Plut., *Aem*. 5.5)\n\nThe institution of adoption was famously abused / creatively applied by Cicero's nemesis Clodius, who had himself adopted into a plebeian family to make him eligible for the tribunate. We also hear more and more about testamentary adoptions (posthumous adoptions by will) in the late Republic, which (unlike the two legal forms of adoption) entailed only taking the name of one's new \"father,\" not formally joining his family. The most famous instance of this is of course the future Augustus' adoption by his great-uncle Julius Caesar. Adoption continued to evolve in the imperial era, when women were allowed to adopt for the first time. It also became, as we have seen, a principle of imperial succession - though no emperor ever passed over his natural son in favor of an adopted one."
]
}
|
[] |
[] |
[
[]
] |
||
1o5hag
|
Is gravity the strongest at the surface of the earth?
|
My morning shower got me thinkin. If you are on the surface of the earth, you have a huge amount of mass underneath you pulling you down. Now let's say you dig a hole a few miles deep. You have less mass below you and now some mass above you effectively pulling you back up. All of this is speculation and was wondering if this is true. Would gravity be strongest on the surface of the earth?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1o5hag/is_gravity_the_strongest_at_the_surface_of_the/
|
{
"a_id": [
"ccp3ldb",
"ccpfa99"
],
"score": [
14,
2
],
"text": [
"That would be true if the Earth was a sphere of uniform density, but since the core is much denser than the mantle and crust, gravity peaks at the barrier between the mantle and the outer core. [Graphs for comparison.](_URL_0_)\n\nYou can think of this as the amount of less dense \"stuff\" that the mantle/crust adds doesn't compensate for the extra distance away from the very dense core.",
"The basic model you would see in most intro classes (see xenneract's graph, the constant density line) would peak at the surface of the planet. \n\nWhy? Inside a spherical shell of constant density, the net force of gravity on a body is zero. If we treat a solid sphere as a bunch of concentric shells, the only mass that contributes to gravity is the mass from shells between the object and the center of mass. Doing the math (mass goes as density\\*volume= rho\\*4/3\\*pi\\*r^(3), force goes as G\\*mass\\*mass/r^(2) =bunch of constants\\*r), inside the planet, the force increases linearly with distance. Outside the planet, the mass is now set, and decreases as 1/r^(2). **Important Notes:** The mass above you *in this model* doesn't pull you back up. For constant density shells (which we're pretending the Earth is), there is no net force from the material above you, because you're *inside* those shells. There is less mass below you, which does decrease the force you'd experience.\n\nIn reality, there's a huge assumption in that model that's nowhere near true: the material in the Earth is constant in density. If density increases linearly as we go away from the center of the Earth, rho goes like a\\*r+b, so mass goes as a'\\*r^(4)+b'\\*r^(3), and the force would go like a''\\*r^(2)+b''\\*r. If density decreases linearly as we go away from the center of the Earth, the leading coefficients (a, a', and a'') are all negative, and you get the linear density line on xenneract's graph. The latter case (decreasing density) is closer to reality. The most realistic model has different densities for different layers of the planet, based on various geophysical measurements (the density impacts propagation of seismic waves, so geologists have developed detailed models of the inner workings of the density of Earth), and lead to the PREM line in the graph."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/File:EarthGravityPREM.svg"
],
[]
] |
|
5y15ts
|
why does nintendo create "artificial demand"
|
This was brought up when amibos came out, but it seems relevant again with the switch. Why do they create fake shortages? I thought it only profited scalpers? Is Nintendo purposefully doing it, if so why, what does it gain them, and why do they still do it if everybody knows?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5y15ts/eli5_why_does_nintendo_create_artificial_demand/
|
{
"a_id": [
"demdh2o",
"demdlpx",
"demedgg"
],
"score": [
5,
25,
3
],
"text": [
"Creating a huge production capacity and only using it for a short period of time is financially costly. Nintendo knows most people will be willing to wait a few weeks if they have to. So there is an incentive to not build a massive temporary capacity. \n\nWe saw this with the Wii, switch, and NesClassic. ",
"There is no evidence they have **ACTUALLY** created fake shortages, this story pops up with virtually every console launch (I remember it for the Playstation 2) but the economics behind it don't work.\n\nNintendo would not make more money by having people fight over a limited set of existing devices. You're right, it only benefits scalpers.\n\nThey simply make devices that sometimes get really popular and have a hard time manufacturing enough to meet demand. Remember, Nintendo has to *spend the money first* to build the devices before it can sell them and make it back. It's hard to convince the Ninty finance guys \"yeah let's build ten billion of them\" until they can prove there's a demand for ten billion.\n\n",
"they do not create an artificial demand, They consistently underestimate demand. \n\nIf it was artificial they would be sat on a pile of products refusing to ship them because reasons. \n\nThe issue Nintendo has is they simply do not manufacture enough, becasue they are terrible at estimating actual demand and seemingly prefer to estimate very low demand to protect themselves encase they screw something up. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
2cdbe3
|
How would a Medieval castle's garrison (say, 1300's) work? How would one join it and how many would be employed at peace?
|
I know ASOIAF gets mistakes when it comes to some medieval aspects, but lords and kings did have standing garrisons, right? I wonder how one would join this garrison if you're *not* a knight, and how would one be trained? Why didn't *everyone* join one if it meant pay, food, and shelter? (if it was voluntary)
Thanks in advance!
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2cdbe3/how_would_a_medieval_castles_garrison_say_1300s/
|
{
"a_id": [
"cjelw9w"
],
"score": [
3
],
"text": [
"Most castles did not have \"garrisons\" per se. The average castle in Europe was the home of a knight. The \"garrison\" would be the knight, any of his family (sons or brothers) who still lived at home and were of fighting age, and his servants and retainers (cooks, grooms, falconer, huntsman, etc.) who could be armed in case of need. In times of danger, the villagers would take refuge in the castle and would be armed with the weapons stored there.\n\nLarger royal castles or fortress castles, or the castles of great nobles might have had a garrison in peace time. Even so, these garrisons were often surprisingly small.\n\nFor example, here are some of the garrisons for important castles guarding the Welsh Marches in about 1160 (a little earlier than the period you are looking for).\n\nThe Pipe roll entries show that Oswestry Castle had a garrison of one knight, two porters and two watchmen between 1160 and 1165 (William Fitz Alan was the lord of the castle, but he was a young child and was a ward of the king. The King appointed Guy Lestrange to administer the Fitz Alan lands, and this is the garrison which Lestrange paid for as shown in his accounts of his guardianship).\n\nThe two other Fitz Alan Welsh border castles of Clun and Ruthin seem to have had the same peacetime garrison of 5 men.\n\nThe Welsh border castles of Shrewsbury and Bridgnorth, seem to have had even smaller garrisons. Shrewsbury was a royal castle, but about 12 miles from the Welsh border and shielded by intervening castles such as Oswestry. It had a garrison of one porter and one watchman. Bridgnorth, another royal castle, slightly further from the border had a garrison of one permanent year round porter.\n\nIn time of danger or war, the troops in these castles would be increased. In the summer of 1165 Henry II used Oswestry Castle as his base for a campaign against Owain Gwynedd (an unsuccessful campaign), and during this summer 200 soldiers were stationed at Oswestry and Knockyn Castles.\n\nAgain, in 1166-67, the border was troubled and 40 soldiers were paid for at Oswestry Castle for two years. For 158 days of one of these years another 60 soldiers, paid for by the local barons, not the King, were also stationed at Oswestry Castle. By 1168, the soldiers at Oswestry castle were reduced to 20 and that garrison seems to have remained until 1174.\n\nSource: \n\n_URL_0_"
]
}
|
[] |
[] |
[
[
"http://books.google.com/books?id=m-TqPC6cRNYC&pg=PA69&lpg=PA69&dq=castle+garrison+size&source=bl&ots=7Gx2JWLr8U&sig=TaP-HLuPzEDuyLjfbOR1AV74Wto&hl=en&sa=X&ei=plTcU4quDsKGyATZmYKADg&ved=0CBwQ6AEwADgU#v=onepage&q=castle%20garrison%20size&f=false"
]
] |
|
48v6q9
|
how come songs/music these days have so many writers yet they only last 3 minutes tops?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/48v6q9/eli5_how_come_songsmusic_these_days_have_so_many/
|
{
"a_id": [
"d0mtca8",
"d0mtni6",
"d0mtota",
"d0mukyw",
"d0n25tn"
],
"score": [
2,
6,
2,
2,
2
],
"text": [
"most hits or really catchy tunes are right around there. there are exceptions but hell look at Beatles songs. ",
"3 minutes is the standard pop song length. Now why are there so many writers? The answer is usually \"samples\". Here's one of my favourite examples: The Kanye West song \"Stronger\", which samples Daft Punk's \"Harder Better Faster Stronger\" which in turn sampled Edwin Birdsong's \"Cola Bottle Baby\" resulting in Kanye's song being credited to West, Bangalter, De Homem- Cristo, and Birdsong. If you see more than three writing credits, it's a safe bet at least some of these people did nothing more than record a song that got sampled in the new song.",
"A song any more than 3 minutes will likely be edited down for radio play. If you look at deeper tracks on an album, some of them will be a bit longer. With this in mind, writers, in order for people to hear all of their work as intended on the radio instead of chopped up for time, likely write their songs so they can be heard in full on the radio.",
"Sometimes one of the writers was responsible for changing one or two words in the original lyrics. ",
"Getting a writer credit isn't that big of deal. If you're in the room and you say, \" Hey, maybe you should say \"purple pajamas\" there. And the main guy goes, \"hey I love that\" you're a writer."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[]
] |
||
33tiu4
|
Looking for a couple of good books for two exams I have coming up. British society 1900-1950 ish
|
Need one for social & economical impacts of world war one. (mainly social)
and need one based on the suffragettes and and pre suffragettes movements.
I just need to get a grasp of the time around those periods, any recommendations would be greatly appreciated!
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/33tiu4/looking_for_a_couple_of_good_books_for_two_exams/
|
{
"a_id": [
"cqoc298"
],
"score": [
2
],
"text": [
"I'd recommend Peter Clarke's *Hope and Glory* (2nd ed, 2004) as a good overview of social, political and economic history of Britain during the 20th century. Based on your interest in sufferage and the impact of the Great War, Id also recommend Nicoletta Gullace's *The Blood of Our Sons* (2002) which looks at how the war impacted the relationship between gender and citizenship. \n\nThat said, as a teacher myself, if this is for an exam I'd recommend focusing first and foremost on the readings assigned for the class. That's the material that you will be directly graded on. "
]
}
|
[] |
[] |
[
[]
] |
|
22fqrx
|
Why does physics assume the existence of elementary particles?
|
To make sure I am asking the question correctly, let me elaborate. Each question seems to lead to another question so I will try to limit this to a small subset.
As I understand the concept of Elementary Particles, fermions and bosons, is that they are not composed of any other particles. In short that EPs are the smallest of all particles. I hope this understanding is correct.
If so, then smashing / destroying say a quark would do what? If there are no other particles of which the quark is composed then what happens to the quark? Does E=MC^2 come into the equation and nothing but energy remains? If so, then what does it mean that the Bosons are the force/field carriers?
Its at this point that particles seem to not be logical any more and circular logic starts to kick in. Or, more likely, that my understanding is faulty. Any one care to give me insight?
|
askscience
|
http://www.reddit.com/r/askscience/comments/22fqrx/why_does_physics_assume_the_existence_of/
|
{
"a_id": [
"cgmej0m",
"cgmeuam",
"cgmg45b",
"cgmgchn"
],
"score": [
8,
56,
22,
13
],
"text": [
" > If so, then smashing / destroying say a quark would do what? If there are no other particles of which the quark is composed then what happens to the quark? Does E=MC2 come into the equation and nothing but energy remains?\n\nIt makes other particles. Physicists use Feynman diagrams to describe these kinds of interactions; [here's some pictures.](_URL_0_)\n\nThe energy is conserved by making other particles. \n\nFor an easy example, [this image shows how an electron and a positron (the antimatter counterpart to an electron) will annihilate and produce two photons.](_URL_1_)",
"Physics does not *assume* the existence of elementary particles. Rather, we construct models, see if they work, and it turns out that models that predict the existence of elementary particles work very well.\n\nWhen you smash particles together, you are not breaking them apart. You are taking them and all their energy -- including the energy present in their mass via E=mc^(2) -- and making it possible for that energy to re-form into new entities.\n\nWe refer to some objects as matter and some as force carriers because of the way we happen to think about different entities and their interactions, but that is not necessary.",
"It might help to stop and think for a while about what the phrase \"elementary particle\" even means.\n\nTo me (and, AFAIK, most real physicists), it means \"a particle that is not itself a collection of smaller particles.\"\n\nThis seems a reasonable definition. It also raises the question \"ok, then what is an elementary particle made of?\"\n\nThat's the question that gets us into fields. The idea that *all of space* is filled with various fields, which are basically just different ways that energy can be stored. A \"particle\", then, is just what you get when there is energy stored in certain ways in certain fields.\n\nFor example, take the electron. It is an excitation (a localized bundle of energy) in the all-pervasive electron field. Higgs boson? Yup. An excitation of the Higgs field.\n\nThese fields do other things besides, but *when* there are little knots of energy in them, those are elementary particles.\n\nAnd as others have said, physicists don't *assume* the existence of these things. Rather, the existence of elementary particles (and their associated fields) is a *model* of reality. That model may or may not be correct. Who knows. All we can say right now is that the predictions the \"standard model\" makes turn out to be extraordinarily accurate. \n\nThe math of the standard model says that when you smash this particle into that particle at such-and-such energy, you'll get the following results, with certain probabilities. And when we try it, that is indeed what we measure coming out of the particle colliders, to a whole lot of decimal places.\n\nAnd this happens time and time again, for many, many (many) different experiments. After a while, even though everybody remembers that the standard model is in fact just a model, we start to talk about it as though it's real. Because it has withstood so much experimental validation without breaking, we start to have high confidence that this model is actually true.",
"I think the conceptual problem you're running into with elementary particles is that you're thinking of them as concrete, pre-existing things that physics and the Standard Model were put together to describe. I think a better point of view would be to consider the elementary particles a useful tool to describe the physics at a very small scale, but not a more philosophically significant concept than a [quasiparticle](_URL_0_) like (for example) a sound wave. Physics uses the language of particles because it is convenient and conceptually familiar, but there's no reason *a priori* to believe that elementary particles are actual objects. They could be described just as well as disturbances in a field, or wells in a curved surface, or attractors in a phase plane. \n \nThat said - if you were to split or otherwise disturb one of these elementary particles, it would tend to return (eventually) to a stable state, whatever that may be. It's entirely possible that this already happens under some experimental conditions, but it happens so quickly and is so difficult to measure that our instruments can't detect these events. Ultimately, physical theory is based on observation - it is a set of rules, applied by human minds, to understand the interactions observed in the universe. So if there's never been such a splitting interaction observed, theory won't need to accommodate it (nor should it) since the objective of physics is not to exhaust every possibility with speculation, but to concisely explain as many observable phenomena as possible. \n \nTo summarize: \n \n1. Particles are an abstraction used to formulate a useful theory about subatomic interaction - not a concrete, ontologically fundamental entity. \n \n2. Until something smaller than an elementary particle is observed, there's no need (or supporting data) to develop a theory for something smaller. "
]
}
|
[] |
[] |
[
[
"http://hyperphysics.phy-astr.gsu.edu/hbase/particles/imgpar/feynm5.gif",
"http://physics-database.group.shef.ac.uk/cbooth/eegg.gif"
],
[],
[],
[
"http://en.wikipedia.org/wiki/Quasiparticle"
]
] |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.