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b28rfs
|
Why do heavier patients need higher doses of medication?
|
At times you can find over the counter medications with dosage charts that correspond to weight. There is also a general understanding that skinnier people will be more sensitive to medications-- particularly sedatives. We can also see this in the amount of alcohol one can consume before blacking out. What are the pharmacodynamics that explain this correlation between potency and patient weight?
|
askscience
|
https://www.reddit.com/r/askscience/comments/b28rfs/why_do_heavier_patients_need_higher_doses_of/
|
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2
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"text": [
"It relates to body fat content and how lipophilic drugs are. Things like general anaesthetics and ethanol are highly lipophilic, and readily distribute into fat. This basically gives the drug a much larger volume to distribute into, thus the concentration of drug in the blood plasma/at it's target site will be lower, so a higher dose would be needed to reach therapeutic concentrations. Partitioning of drugs into fat can do some complicated things to the pharmacokinetics of drugs. As fat also has a relatively poor blood supply/rate of blood flow, it can take a while for drugs to distribute into fat (which can also lead to higher peak plasma concentrations of drug when a larger dose is used, but isn't yet distributed into fat), but fat later acts as a reservoir, maintaining the plasma concentration of a drug as it is being cleared from the body. This can contribute to effects such as the \"anaesthetic hangover\" after GA\n\nSource: currently studying pharm on a veterinary medicine course ",
"It's very simple. The activity of any chemical is proportional to its concentration when as diluted, as most medicines are. Pain medicine and insulin work that way for instance.\n\nThe exception are that the drug acts as a catalyst to start reactions between the body's own chemicals, then its concentration does not matter much except for the speed of its effects. Vaccines that trigger an immune response are example of this. They just need to be strong enough to start an effective reaction, and it does not matter much if it takes 5 or 15 days.\n\nSo, you have drugs for which dose don't matter, and you have drugs for which concentration determines their effect."
]
}
|
[] |
[] |
[
[],
[]
] |
|
4y93pl
|
a presidential pardon decades after death
|
What is the purpose of someone asking for a presidential pardon for someone who died 76 years ago?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4y93pl/eli5_a_presidential_pardon_decades_after_death/
|
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"Basically it's just to officially acknowledge that the person was innocent. It brings some justice to the family",
"Well, it officially acknowledges an injustice was done. Otherwise, there will be people out there who will still be insisting that the person is guilty, I guarantee it. For example--HUGE scandal in France in the late 19th/early 20th century. A military officer, Alfred Dreyfuss, was accused of treason. He was tried and imprisoned. He was Jewish and his alleged guilt was used to condemn the whole French Jewish community. All kinds of attacks against Jews were made. The thing was, Dreyfuss was innocent. The guilt was with another guy, not Jewish, who framed Dreyfuss. Those wanting to minimize the scandal thought Dreyfuss would be a great scapegoat. Blame Jews, not corruption in the army! This controversy tore French society apart. Eventually, Dreyfuss was freed. He's pretty much universally considered to be innocent...except that the French army has never exonerated him. It would be an embarrassing admission. It would affirm not only his innocence, but the guilt of all those who attacked him and attacked Jews. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
3p8u20
|
Everything else equal, what effect does tire size have on a vehicle's gas mileage?
|
...maybe saying everything else equal is a bit cosmic?
|
askscience
|
https://www.reddit.com/r/askscience/comments/3p8u20/everything_else_equal_what_effect_does_tire_size/
|
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"Changing the tire size will essentially change the gearing ratio. If the car is manual you could get essentially identical function and efficiency by shifting gears appropriately. If the car is automatic then the shifting may be suboptimal depending on whether the speedometer is used to control shifting, and whether the speed is correctly measured despite different tire size.",
"First things first it depends on what you mean by tire size. The standard for labeling size is tread footprint/sidewall height/rim size. \n\nChanging any one of the measurements effect weight of the tire, which in turn effects gas mileage by allowing the same amount of power to pull less weight. \n\nThe measurement most likely to change weight is rim size, and composition.\nSo for example an alluminium alloy 15\" rim will weigh less than a steel alloy 15\", or an alluminium alloy 16\". \n\nWhen you increase the tread footprint you increase grip (example: Moving from a 225/50/15 to a 275/50/15) when you increase grip, you decrease mileage because you need more power to break traction, effectively causing more weight. \nSidewall size also has an effect on weight, but not as much. \n\nOne thing of note concerning sidewall size is the larger sidewall, the more room for fluctuation. The more fluctuation in the sidewall, the hotter it gets, which decreases stability, and traction. \n\nTraction(grip) plays a surprising amount into fuel economy because the more traction you have, the higher the rolling resistance, which again means you need more power to move the tire than with a lower resistance.\n\nAs /u/datanaut said, your vehicle is geared specifically for the stock tire size, so changing sizes is equivocal to changing gearing. \n\nIf you don't know anything about gearing, its responsible for dictating speeds at certain RPM. so for example, my motorcycle travels 80mph at 6krpm, in 6th gear. Changing my sprockets would change my speed in respect to my RPM. A smaller gear(tire) will decrease speed at 6krpm in 6th gear, but will increase my rate of acceleration because there is less distance for the gear to travel to complete one cycle.\n\nI hope this answers your question fully.",
"Tire size and gearbox ratio is a trade off between to parameters, **speed and torque**, a larger tyre will give you more speed and less torque, a smaller tyre will give less speed and more torque.\n\nSo you set up tyre size and gearbox ratio such that your car is operating at its most efficient revs for typical driving conditions.\n\nSo if the efficiency curve of your engine peaks at 3000 RPM, the gear ratios and tyre size are set so your speed will be 'typical' when in top gear and at about 3000 rpm."
]
}
|
[] |
[] |
[
[],
[],
[]
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|
b97ri2
|
when something breaks the sound barrier. what is the visible cone shaped thing behind it?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/b97ri2/eli5_when_something_breaks_the_sound_barrier_what/
|
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"text": [
"Are you talking about [this](_URL_0_)? If so, it's called a vapor cone or a shock collar. It's a cone of water vapor that can form when a plane flies at high speeds (transonic but not necessarily supersonic, although some airflow will be supersonic) through moist air. The area behind the shock wave has a low air pressure, and if the pressure drops below the dew point, water will condensate out. It's conical in shape because that's the shape of the shockwave itself.\n\n & #x200B;"
]
}
|
[] |
[] |
[
[
"https://upload.wikimedia.org/wikipedia/commons/e/e1/FA-18_going_transonic.JPG"
]
] |
||
bodfxl
|
how does oxygen reach the brain?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bodfxl/eli5_how_does_oxygen_reach_the_brain/
|
{
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"enesweh"
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"text": [
"The red cells in your blood pick up oxygen in your lungs, then the heart pumps the blood around your body, including to the brain."
]
}
|
[] |
[] |
[
[]
] |
||
3zs7kn
|
what is mb/s and how is it related to mb/s
|
In terms of data transfer speeds.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3zs7kn/eli5_what_is_mbs_and_how_is_it_related_to_mbs/
|
{
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"text": [
"Mb/s is Megabits per second. MB/s is MegaBytes per second. A Byte is 8 bits, so MB/s is faster by a factor of 8x.",
"In addition to what others have said. Mb/s is typically used when referring to network speeds, where as MB/s is referring to file transfer speeds."
]
}
|
[] |
[] |
[
[],
[]
] |
|
17gsp7
|
How is it that if Earth exerts a force of gravity on you of 600N, then you also exert a force of gravity on Earth of 600N?
|
askscience
|
http://www.reddit.com/r/askscience/comments/17gsp7/how_is_it_that_if_earth_exerts_a_force_of_gravity/
|
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"text": [
"I don't really know what you're asking. If you're wondering why the Earth doesn't move because of the 600 N you're exerting on it, it's because the earth is very big. A force of 600 N on an object the size of the earth causes it to accelerate by 1 x 10^-22 m/s^2 which is VERY small. ",
"Could you elaborate on your question? That is, the question of \"how is this fact a fact\" is very difficult to answer with anything except \"well... that's the fact.\"",
"The gravitational force is proportional to the product of the two masses involved. So the larger the mass that's pulling on you is, the stronger you are attracted because there is more stuff to pull. But also the more mass you have, the stronger you are pulled because there is more mass to be pulled on.\n\nSo the Earth pulling on you is a whole lot of mass pulling on a little mass, but you pulling on the Earth is a little mass pulling on a whole lot of mass. ",
"I think what's confusing you here is a misinterpretation of the underlying meaning of Newton's third law. From a deep perspective, there aren't actually two independent forces involved. It isn't you pulling on the earth *and* the earth pulling back. Rather, there is a single attractive force of 600N *between* you and the earth.",
"ELI5: Because forces act *between* things. You can't compress a spring just by pushing on one end only. You have to push on both ends. Now imagine putting a spring between you and the Earth. The force between you and Earth is what compresses the spring."
]
}
|
[] |
[] |
[
[],
[],
[],
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||
v5v6g
|
Question regarding Wasps/stinging insects: How did the biology of a stinging insect evolve correctly to produce a formula that would effectively hurt or "sting" its victim?
|
First off, I believe in evolution, so this isn't a challenge or a gotcha question, I just got to thinking today after getting stung by a small sweat bee.
Seems like it would take long enough for a strand of insect to evolve a stinger. I can see how it might could develop over a long period of time, but then on a different dimension altogether is the venom that the insect throws out into the wound the stinger has made. Was it just a matter of coincidence or did the evolution process somehow take an introspective evaluation on that insect's nervous system and subsequently develop a serum that would be effective in turning away would-be assailants? It just seems like an incredible stretch that the anatomy of a bee could somehow "know" that whatever stuff its injecting into another animal would result in a painful nervous stimulus. Maybe the venom failed for millions of generations until finally it got it right?
Anyway, I thought it was a good question, just goes to show how amazing the evolution process is.
|
askscience
|
http://www.reddit.com/r/askscience/comments/v5v6g/question_regarding_waspsstinging_insects_how_did/
|
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"Its a series of steps and adaptations. They evolve a more potent venom and a stronger stinger when its main prey or attacker devolps to have a natural resistance or thick exoskeleton. Its essentialy a very long process of one-uping the other species. Oh and mods can go ahead and delete this if they want im at work on my phone and dont have time to pull up sources this is just what i have been taught.",
"I'm not the best person to answer this but I googled the evolution of bee stings and found this. Perhaps someone else could run with this or elaborate on it: \n\n\"The bee's stinger evolved originally for inter-bee combat between members of different hives, and the barbs evolved later as an anti-mammal defense: a barbed stinger can still penetrate the chitinous plates of another bee's exoskeleton and retract safely.\"\n\nSource: _URL_0_"
]
}
|
[] |
[] |
[
[],
[
"http://www.sciencedaily.com/articles/b/bee_sting.htm"
]
] |
|
3z7chd
|
Why did Christianity (Nestorianism) fail to create a significant and lasting Chinese Christian population, while Islam did?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3z7chd/why_did_christianity_nestorianism_fail_to_create/
|
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"I can't comment on Islam, but I can explain why Chinese christianity did not last to the modern day (of course, there are plenty of Christians now, but they only date back to European missionary activity).\n\nFirst, about its origins. My source for the first part of this is a tablet in a museum in Xian (or rather, the internet translation of this: I couldn't actually read it, it's too decayed and in ancient Chinese, which I can't read anyway). \nThe tablet was written by Persian (Nestorian*) missionaries. It described the last 200 years of Chinese Christian activity, setting up churches, evangelising, etc. However, from what it said, they don't seem to have made a huge number of converts.\n\nAccording to a Chinese Christians I've discussed this with, the mainstream view of Chinese Christian scholars** is that the early churches were \"very Buddhistic\". What this means is, they became more and more similar to Buddhist practices, and eventually faded away as a strongly defined entity. In a German museum, there is a piece of art of Tang-dynasty Christians celebrating palm Sunday; other than the palms, they do not seem very different from Buddhist worshippers.\nA number of modern Chinese Christian leaders (read about the recent issues in Wenzhou and this will come up) have expressed reluctance to the Chinese governments aims of sinicising Christianity, because they believe that this could cause Christianity to lose any unique characteristics and thus fade away, as it did before.\n\nNow, Nestorian Christianity returned to China in the Yuan dynasty, as it was the religion of certain Mongol tribes. However, it wasn't given government support, and being associated with foreign conquerers, again didn't make many converts. When the Mongols were expelled by the Ming, as with Tengrism, it was seen as a foreign Mongol religion, that should be expelled from China.\n\nAs I said, I don't know why Islam managed to create a strong community (I assume you are referring to Huizi; with the Uighers it's the same way it spread to central Asia generally, though the silk road), only why Christianity didn't.\nI'd be curious if anyone knows the history of the Huizi?\n\n*Bear in mind that the \"Nestorian Church\" probably wasn't actually Nestorian in doctrine, they just tolerated Nestorians while the European churches didn't.\n\n**As I said, this is (I believe) the mainstream view of Chinese Christian scholars. I feel it's important to point out that it is used as a narrative of resisting the government; it's possible therefore that this view is unreliable. I don't know of any non-Christian, Chinese historians who study the history of Christianity in China, to compare it to. It seems like a reasonable hypothesis, but I feel I should point this out.",
"So, I've done a bit more looking around on this topic, and discovered something I did not know (and I find it very interesting that no Chinese Christians have ever told me this).\nWhen Emperor Wuzong made Buddhism illegal in the great Anti-Buddhist Persecution of 845AD, he also banished all Zorastrians and Christians. \"As for the Tai-Ch’in and Muh-hu forms of worship, since Buddhism has already been cast out, these heresies alone must not be allowed to survive. People belonging to these also are to be compelled to return to the world, belong again to their own districts, and become tax payers. As for foreigners, let them be returned to their own countries, there to suffer restraint.\"\nTai-Ch'in (or Da Qin as modern Pinyin would say it) means Roman, and Christians were generally referred to as Romans (well, actually by this time it generally referred to Syria specifically).\nYou can read the pronouncement here: _URL_0_"
]
}
|
[] |
[] |
[
[],
[
"http://www.religion-online.org/showchapter.asp?title=1553&C=1363"
]
] |
||
5npdnp
|
why are us troops being deployed to poland?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5npdnp/eli5_why_are_us_troops_being_deployed_to_poland/
|
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"text": [
"Because Russia. Like it or not, NATO is primarily the Club of Countries the US Promises To Protect. Its ludicrously massive military is what everyone wants on their side.\n\nAfter Russia's adventures in the Crimea and Eastern Ukraine, there are suspicions within NATO that either Poland or the Baltics might suddenly find an [oppressed Russian minority](_URL_0_) within their borders, joined by \"vacationing\" Russian officers, and suddenly Russia's border will shift westwards. While Ukraine isn't NATO, those other states are, hence NATO (i.e. US) troops are pooling into there.\n\nRussia of course denies ties to the rebels in Eastern Ukraine and claims that it's Crimea's democratic choice, while blaming the West for the \"Nazi junta\" in Ukraine and the thoughtless Kosovo precedent allowing such democratic choices. Hence Poland has nothing to fear... for now."
]
}
|
[] |
[] |
[
[
"http://imgur.com/a/ujFhp"
]
] |
||
1h8c12
|
Did civilizations like Rome and Greece participate in espionage?
|
I googled for it but I didn't see any good sources for information. I'm just curious what kind records we have of espionage in ancient cultures.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1h8c12/did_civilizations_like_rome_and_greece/
|
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"A contemporary source would be Historia Augusta, but dont expect to find that many details. Chapter 11, part 3-4 in [Historia Augusta](_URL_1_) (Hadrian) ; *He removed from office Septicius Clarus, the prefect of the guard, and Suetonius Tranquillus, the imperial secretary, and many others besides, because without his consent they had been conducting themselves toward his wife, Sabina, in a more informal fashion than the etiquette of the court demanded. And, as he was himself wont to say, he would have sent away his wife too, on the ground of ill-temper and irritability, had he been merely a private citizen. Moreover, his vigilance was not confined to his own household but extended to those of his friends, and by means of his private agents he even pried into all their secrets, and so skilfully that they were never aware that the Emperor was acquainted with their private lives until he revealed it himself.*\n\nI have read a description of [Ammian](_URL_0_) that describes him as an roman agent or spy.. cant find it now but he did write a [Res Gestae](_URL_2_) which is available online. Happy reading!",
"The Trojan War records espionage in ancient cultures. From WP, \"Sinon, an Achaean spy, signaled the fleet stationed at Tenedos when 'it was midnight and the clear moon was rising'\"",
"You may find the answers in this thread fruitful:\n\n_URL_0_",
"I have no clue about the extent/organisation of espionage in those civilizations, but I *do* know that Julius Caesar often coded his messages to his generals. One of those encryption techniques is named after him, and is called the \"Caesar cipher\". You can read more about this [here](_URL_0_) , although I can't vouch for its accuracy.\n\n",
"Yes, quite extensively. Rose Mary Sheldon, professor of history at Virginia Military Institute, has written [a number of publications](_URL_8_) on Roman intelligence (broadly construed, and thus not always including what we would think of as espionage). [Here](_URL_10_)'s an article of hers that cites many examples, including: \n\n* a list of conspirators delivered to Julius Caesar shortly before his death^1\n* the use of disguise by Roman soldiers investigating the fearsome Ciminian Forest, under Etruscan control at the time ([cited in Livy](_URL_6_))\n* Hannibal's extensive use of spies against Rome during the Punic Wars (for example at the [Battle of the Trebia](_URL_9_)\\), and Scipio Africanus's eventual use of retaliatory espionage (for example at the [Battle of Utica](_URL_4_)\\)^2\n* the [frumentarii](_URL_7_) (domestic spies).\n\nSheldon argues that Rome had no state intelligence service because of the predominance of private intelligence networks employed by senators to carry out personal intrigues in the midst of complex senatorial politics; few records survive of these machinations. \"Every Roman aristocrat had his private network of business associates, informers, clansmen, slaves, or agents (male or female) who could keep him informed on the latest happenings in the Senate or his own home,\" she writes.\n\n[Here](_URL_3_) (PDF warning) is an article by Sheldon on the Byzantine intelligence service, and [here](_URL_0_) is the Google Books preview of her book *Intelligence Activities in Ancient Rome.* \n\nedit: formatting\n\n---- \n\n^1 Curiously, her first example seems to have the least historical evidence, at least that I can find. I think she's confusing the Shakespeare character [Artemidorus](_URL_5_) with a real person? Nicolaus of Damascus's [account](_URL_1_) mentions that \"[Caesar's] friends were alarmed at certain rumors and tried to stop him going to the Senate-house,\" but Brutus successfully dismissed these as \"the idle gossip of stupid men.\" \n^2 See also Terry Crowdy's *[The Enemy Within](_URL_2_)*, chapter 2.",
"Absolutely, in fact, the Caesar cipher is among the best known substitution codes in the world and we have surviving literary records detailing its use by Julius Caesar in his military campaigns.\n\nEncryption is a great indicator of a need to keep secrets not just physically secure but informationally secure to boot. In other words; only exists if you think someone else is able to capture your correspondence and make use of it. It's a form of counter-espionage in its own right and proof positive of at least a rudimentary awareness of the same in the opposing force. "
]
}
|
[] |
[] |
[
[
"http://penelope.uchicago.edu/Thayer/E/Roman/Texts/Ammian/Introduction*.html",
"http://penelope.uchicago.edu/Thayer/E/Roman/Texts/Historia_Augusta/home.html",
"http://penelope.uchicago.edu/Thayer/E/Roman/Texts/Ammian/"
],
[],
[
"http://www.reddit.com/r/AskHistorians/comments/19pstl/did_ancient_empires_have_intelligence_agencies/"
],
[
"http://en.wikipedia.org/wiki/Caesar_cipher"
],
[
"http://books.google.com/books?id=qAmtMo1M8MgC&printsec=frontcover#v=onepage&q&f=false",
"http://www.eyewitnesstohistory.com/caesar2.htm",
"http://books.google.com/books?id=jSC7GccDRtsC&printsec=frontcover&q&f=false#v=onepage&q&f=false",
"http://www.vmi.edu/uploadedFiles/Faculty_Webs/HIST/SheldonRM/Courses/Restricted/Dvornik%203.pdf",
"http://en.wikipedia.org/wiki/Battle_of_Utica_(203_BC\\)#Peace_negotiations",
"http://www.playshakespeare.com/julius-caesar/scenes/361-act-ii-scene-3",
"http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.02.0026%3Abook%3D9%3Achapter%3D36",
"http://en.wikipedia.org/wiki/Frumentarii",
"http://www.vmi.edu/fswebs.aspx?tid=26499&id=26519",
"http://en.wikipedia.org/wiki/Battle_of_the_Trebia#Mago.27s_ambush",
"http://www.historynet.com/espionage-in-ancient-rome.htm"
],
[]
] |
|
5hfedt
|
how do people build programs inside of minecraft?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5hfedt/eli5_how_do_people_build_programs_inside_of/
|
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"Practically the same question was posted less than an hour ago: \n_URL_0_",
"Early computers were basically a bunch of switches that were either ON or OFF. By arranging some amount of switches ON, you would store that information.\n\nIn MineCraft, you can build circuits using RedStone -- a powder which you can form lines of, that carry power from a RedStone Torch, or some form of trigger (pressure plate, switch, etc) for a certain distance, and can be used to trigger effects like pistons, doors, explosives, etc.\n\nWhat people do to build a computer in MineCraft is, they have a bunch of switches which they can set either ON or OFF, like an early computer. A lot ([a LOT!!!](_URL_0_)) of RedStone goes through a bunch of Logic Gates (I'll explain those in the next comment for formatting) and ends up doing whatever the creator wants them to do, such as turning on a bunch of lights (like pixels on your computer screen) to make an image."
]
}
|
[] |
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[
"https://www.reddit.com/r/explainlikeimfive/comments/5hf59l/eli5_redstone_in_minecraft_to_make_calculators/"
],
[
"http://i.imgur.com/OCDXAhO.jpg"
]
] |
||
7ravti
|
Why were smaller penises desirable in classical civilisation?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7ravti/why_were_smaller_penises_desirable_in_classical/
|
{
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"text": [
"You might enjoy /u/PapiriusCursor's answer to [Ancient Greek men thought the ideal male body possessed a small penis. Do we have any idea what Greek women thought?](_URL_0_)."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/513rl2/ancient_greek_men_thought_the_ideal_male_body/d794kh4/?utm_content=permalink&utm_medium=front&utm_source=reddit&utm_name=AskHistorians"
]
] |
||
33knqg
|
How devout were ancient people when it came to their religion(s)?
|
I saw a documentary a while ago about ancient Europeans and how a body of a viking or something had been unearthed with tools and other things in his grave. The archeologists stated with the utmost confidence that this must've meant that those people believed in life after death and that the deceased could bring those tools with, and then use them in, the afterlife. But how much of that sort of religious stuff did ancient people *really* believe?
Think about it like this: On paper, America is a "christian" nation. If only a select few pieces of evidence remained from our civilization, depending on what those pieces were, future people may very well think we were all a deeply pious, Jesus-loving people. When in actuality, we love to drink and fuck and do very un-Jesusy things. Even among my Christian friends that still go to church, most only do so on holidays and the few that go every Sunday do so with a wicked hangover from the rage-fest the night before and grumble about it the whole time. Theres a very vocal, far-right Christian movement in this country for sure, but they are the crazy and loud minority. Most people try to simply balance keeping up family traditions with having fun. As a whole, we are far more Homer Simpson, and far less Ned Flanders (and my theory is that we have *always* been that way.)
So basically: When we find an ancient body buried with tools, did the deceased *truly* think he would be using them in the afterlife? Or did his kin begrudgingly stuff very good and useful items in his coffin because some high priest would give them the stink eye if they didn't? And are there any candid writings or other evidence from any civilization that had these customs that support the latter?
Thanks in advance!
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/33knqg/how_devout_were_ancient_people_when_it_came_to/
|
{
"a_id": [
"cqlx2k8"
],
"score": [
17
],
"text": [
"My reference point is pre-Christian, which has it's own problems, but can shed some light on your question. Ancient Greek religion is largely understood in the socio-cultural terms that /u/Fireproofspider has already referred to. \"Belief\" isn't a term that really enters the religious equation until Christian times. Also, there were no sacred texts, no clergy or any explicit ten commandment like prohibitions. So, it's a really good context in which to explore your question, it's the ultimate \"practiced\" religion. The question of whether the average Greek person believed in their mythology, like the labours of Hercules or Orpheus' trip to the underworld, is for the most part anachronistic. Individual cities had their own special gods and myths, but could also refer to the pantheon of gods to participate in the wider Hellenic community. These stories, and the ritual sacrifices and burials associated with them, were the language with which people engaged each other and with things beyond their control. Festivals were their weekends, sacrifices their BBQs, festival performances their cinemas and Dionysiac revels their frat parties. Religion was more ingrained in their lives than we can easily imagine.\n\nThis isn't to say that the same social dynamics (Homer vs. Ned) didn't exist. We have great sources from people like Plutarch and Theophrastus who give us each a characterisation of the overly superstitious man. This Ned like figure goes to the temple constantly and consults oracles as to what he should have for lunch, and the audience are clearly having a laugh at his expense. We've also got radicals like Plato who question the very existence of god. So we can imagine some kind of spectrum of religiosity, but the middle is very thick and the extremes are very thin.\n\nSo, my take on your questions is that the two aren't mutually exclusive (in this context at least). Maybe people did begrudge losing their best stuff in burial rites, but at the same time we can't extend that all the way to our modern cynicism."
]
}
|
[] |
[] |
[
[]
] |
|
egoo7j
|
how is the videogame skyrim seemingly endless?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/egoo7j/eli5_how_is_the_videogame_skyrim_seemingly_endless/
|
{
"a_id": [
"fc81aig"
],
"score": [
7
],
"text": [
"A small portion of the quests are procedurally generated. This means that there are is technically an infinite amount of meaningless fetch quests that reset every \\~3-ish in-game days. Every gathering node is preset and finite, though, they just respawn."
]
}
|
[] |
[] |
[
[]
] |
||
55h377
|
In terms of anatomy, why are some voices husky and some smooth?
|
askscience
|
https://www.reddit.com/r/askscience/comments/55h377/in_terms_of_anatomy_why_are_some_voices_husky_and/
|
{
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"d8avq3b",
"d8avwch",
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],
"score": [
21,
163,
11
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"text": [
"It has to do with your vocal cords. [This link](_URL_0_) (Warning, sort of gross) is a video of a camera recording someone's vocal cords while they talk and sing. The white area in the middle is the vocal cords. They're very easy to damage in the long run, through things like excessive yelling or singing. When they get damaged, the voice becomes more husky or scratchy, and it can be hard to reverse the damage. People with smooth voices generally have healthier vocal cords.",
"If you mean husky as in rough (a long-term smoker's voice would be an extreme example of this), the answer is that there are asymmetries along the edges of the vocal cords. So when the vocal cords adduct, the mucosal wave that kind of vibrates between the cords is off and the sound comes out rougher. This kind of asymmetry could be caused by something like a little bit of swelling after a long night of talking in a loud place, by a benign pathology like a polyp or nodules, or by something like a tumor. I've heard from a colleague about one of her clients who is an actress--she spends a few minutes screaming each night before bed to keep her rough voice (not recommended). \n\nIf you mean husky as in breathy (think Marilyn Monroe's voice), the breathiness comes from the vocal cords not achieving full adduction during phonation. This can be physiological if there is some kind of structural or neurological deficit but this is something we also have the ability to control ourselves. \n\nSource--I'm a speech pathologist",
"Finally an anatomy question! My final dissertation and dissection for my degree in Human Anatomy was focused on the head and neck, especially the laryngeal and tracheal apparatus - you are in luck!\n\nThe vocal cords are the free edge of muscles (or they are tendinous bands) that connect the thyroid cartilage (the biggest cartilage in your neck) and the arytenoid cartilages (small cartilages that can move and twist when other muscles pull on them). The movement of the arytenoid cartilages there changes the voice pitch by tightening or loosening the vocal cords. This is done by the Vocalis muscle moving the arytenoid cartilages, interestingly a skeletal muscle (it is consciously controlled by the brain, not an automatic response) and so disease affecting skeletal muscles such as motor neuron disease will often result in changes/atrophy of vocalis and changes in, or loss of, the voice.\n\nHowever the vocal folds are mucous membranes that drape over these tight vocal cords, these are what open and close to change the column of air travelling through the vocal apparatus to change the voice. \n\nMucous membranes are easily damaged over time, smoking is a good exmaple of this. Smoking with cause death of the cells in the membranes, especially of the goblet cells (the specialised mucous producing cells) embedded in the membrane. Overtime this destruction of the membranes and the mucous producing cells damages the membranes and makes them drier, they rub together instead of gliding smoothly and produce a huskier voice.\n\nIf you are interested in the anatomy the vocal cords (the sturdier bits that the mucous membranes drape over) are called the vestibular ligament of the quadrangular membrane - this forms the 'false' vocal cords high up in the trachea and are not really involved in sound production but more in the resonance of the voice eg if the voice is a deep bass or squeakier. The 'true' vocal cords are lower down in the trachea and formed from the vocal ligament of the cricothyroid membrane, this is involved directly in sound production. \n\nThe mucous membrane covering the 'true' vocal cords will only just touch (ie wont fully close) during vocalisations, the vibration of the membranes against each other as the column of air travels through the tiny gap forms sounds - damaged mucous membranes will vibrate more (compared to tight, smooth, healthy membranes) and form husky voices."
]
}
|
[] |
[] |
[
[
"https://www.youtube.com/watch?v=D6mLc9gOgVA"
],
[],
[]
] |
||
6amq92
|
why is a long one hour walk (4 miles) as tiring as a hard workout, but the walk burns far, far less calories?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6amq92/eli5why_is_a_long_one_hour_walk_4_miles_as_tiring/
|
{
"a_id": [
"dhfqerr"
],
"score": [
3
],
"text": [
"Unless you're walking over rough terrain or up steep inclines a 4 mile walk should not be tiring on the level of a strenuous workout. In general your perceived exertion is a good guide for how fast you're burning calories "
]
}
|
[] |
[] |
[
[]
] |
||
f6vyhv
|
scars
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/f6vyhv/eli5_scars/
|
{
"a_id": [
"fi7bxjp"
],
"score": [
3
],
"text": [
"They would and do exfoliate, eventually. The “lifespan” of a scar is dependent on how deep in the skin it is, and the size of the scar. As time passes, all or parts of the scar tissue will be pushed out. This is why some scars disappear over time, especially with proper skin care. However, if a scar is particularly deep, parts of it may take increasingly long amounts of time to ever reach the surface, and some parts never will. This is why some scars made fade in appearance, but will still be present even upon death."
]
}
|
[] |
[] |
[
[]
] |
||
3ixs98
|
If gravity is the weakest fundamental force, how is it able to have a noticeable impact across such greater distances?
|
askscience
|
https://www.reddit.com/r/askscience/comments/3ixs98/if_gravity_is_the_weakest_fundamental_force_how/
|
{
"a_id": [
"cukngdk",
"cukq4x9"
],
"score": [
40,
3
],
"text": [
"Because there is no anti gravity. The earth is made of a huge number of particles with different electric charges, but on average they all cancel out so that the earth as a whole has no net charge. Because of this the electrostatic attraction of the earth to other planets/stars is very small. In contrast, all the mass of the particles in the earth add up positively, so that the gravitational attraction of the earth is due to the sum of the effects of all is parts. If the planets were only made of positively charged particles, their electrostatic repulsion would be huge and totally swamp the effect of gravity.",
"Gravity acts on mass (actually energy and momentum, but let's keep it Newtonian), which is always positive, while all other forces act on charges, which cancel out on average.\n\nLet us keep in mind that the gravitational field scales as 1/r^2 for large distance.\n\nAn astronomical object such as a planet, star, galaxy, etc. is electrically neutral, so the electromagnetic force has no strong impact over long distances. An electrically charged object would carry an em. field that goes to far distance as 1/r^2, like gravity, but with an electrically neutral object, the field goes as 1/r^3 at most (these are magnetic fields, or higher multipole electric fields due to inhomogeneous charge distributions).\n\nSince for astronomical scales r, 1/r^2 > > 1/r^3, gravity dominates electromagnetism.\n\nFor the strong force and colour charge, the same basic argument applies, except that due to short-scale confinement, colour-neutral particles appear already at the level of hadrons (protons and neutrons in everyday matter). Therefore, there is no inhomogeneity in the distribution of colour charge above the length scale of a hadron. The resulting force field decays exponentially over the length scale of an atomic nucleus (because the effective interaction is mediated by the massive pions).\n\nSo the strong force is a lot weaker than the EM force still, since it decays as exp(-r / r_nucleus) instead of 1/r^3.\n\nThe weak force inherently decays exponentially with distance (which is equivalent to say that the mediating boson is massive). The length scale over which this exponential decays is about 600 times shorter than that of the strong interaction (because the W and Z bosons are about 600 times heavier than the charged and neutral pions).\n\nTherefore, the weak force must be still a LOT weaker than the strong force on astronomical scales, because it decays over distances about 1/600 the size of an atomic nucleus."
]
}
|
[] |
[] |
[
[],
[]
] |
||
3kqqzl
|
major differences between eastern orthodox and catholicism besides religious leader's authority?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3kqqzl/eli5_major_differences_between_eastern_orthodox/
|
{
"a_id": [
"cuzsx75"
],
"score": [
4
],
"text": [
"Authority is the big one.\n\n* Catholics mostly^1 use the Roman Rite liturgy; Orthodox groups tend to have their own liturgies.\n\n* Catholics still say the Holy Spirit proceeds \"from the Father and the Son\"; Orthodox usually draw more subtle nuances and may say the Holy Spirit proceeds \"from the Father through the Son\". \n\n* Local groups of Catholics and Orthodox have their own saints most likely to be venerated.\n\n* There's a couple books in the Orthodox list of Bible books (canon) that aren't in the Catholic canon. \n\n* Orthodox ordain married men to become priests; Catholics don't^1 . \n\n\n\n^(1. There are \"Eastern Rites\", who are technically Catholic and not Orthodox, because they accept the authority of the pope... but the Eastern Rite Catholics otherwise \"look\" more Orthodox, with their own liturgies and ordaining married men and whatnot. They are Catholic but not \"Roman Rite\".) "
]
}
|
[] |
[] |
[
[]
] |
||
1yizor
|
why do so many law enforcers/military personnel support their governments during popular uprising?
|
During the Ukraine and Venezuela protests we hear a lot about how civilians are clashing with police forces and the National Guard, etc. Government agencies committing atrocities.
Why is this? I can sort of understand "duty to country" but surely many of these people would conclude that their country is more than just its current government policies. I can understand the Venezuela bike gangs wanting to maintain the status quo and keep themselves fed and in power because a new government might crack down on them. But surely the success of an uprising would vindicate any military/police for what would have been dereliction of duty if the government did stay in power. Some of these people have got to be firing on their own family members.
Sorry if this sounds disjointed, very stream-of-consciousy.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1yizor/eli5_why_do_so_many_law_enforcersmilitary/
|
{
"a_id": [
"cfkxgsz",
"cfkxka8",
"cfkxuxr",
"cfky7vm",
"cflap70"
],
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2,
2,
6,
3,
2
],
"text": [
"Paychecks and false security",
"The types of people who become cops and military also tend to be OK with authority and think serious disagreement with the government is inappropriate/misguided at best.\n\nSee also: the eternal debate between \"fix the system from the inside\" versus \"it's too broken, it needs to be replaced.\"",
"Milgram's experiment:\n\n_URL_0_",
"I'm 61 years old. I served for six years in the United States Marine Corps. (During the Viet Nam era, but not in country) At no time in my life, under any but the most absolute circumstances (i.e. committing murders) would I fire upon students in my own country. If I were ordered to shoot students for standing in the streets shouting, I'd throw down my rifle. I'd bet that it was actually very few of the police/military who actually pulled triggers in Kiev. It kills me to think otherwise. I've known some really bad hateful racist extremist people in my life, so I can see these atrocities happening, (remember Kent State) but I believe I would die before shooting into a crowd of students.",
"In Ukraine and Venezuela, a large share of the people support the government. It's not like North Korea. \n\n\nFurther, people employed in law enforcement or military are often biased towards stability and order rather than upheavals. Opposite for students/young people."
]
}
|
[] |
[] |
[
[],
[],
[
"https://www.youtube.com/watch?v=BcvSNg0HZwk"
],
[],
[]
] |
|
s4ezv
|
Why can you lift a bigger weight after warming up?
|
askscience
|
http://www.reddit.com/r/askscience/comments/s4ezv/why_can_you_lift_a_bigger_weight_after_warming_up/
|
{
"a_id": [
"c4b1hn5"
],
"score": [
2
],
"text": [
"Do we know that this is the case? Or is it that you can lift more weight **safely** after warmup?"
]
}
|
[] |
[] |
[
[]
] |
||
32wy16
|
Why are some groups of animals, like rodents, not sexually dimorphic? (or at least as obvious as other mammals) How have social systems pressured changes in sexual dimorphism? How are species that aren't sexually dimorphic able to differentiate sexes before encounters?
|
askscience
|
http://www.reddit.com/r/askscience/comments/32wy16/why_are_some_groups_of_animals_like_rodents_not/
|
{
"a_id": [
"cqfh8h7",
"cqfkco7"
],
"score": [
7,
3
],
"text": [
"How are you defining \"dimorphism\"? Are you approaching it with human bias towards visible differences?\n\nRemember that there are other important sensory and behavioral clues to look for. Smell, in particular during estrus, is quite powerful, as are certain innate behaviors associated with mating, such as becoming more accommodating to the approach of a stranger.\n\nAlso, consider that even in dimorphic species there are same-sex encounters that lead to partial (or more) mating behaviors, from courtship up to pair bonding. ",
"Sexual dimorphism is usually the result of precopulatory sexual selection via either mate choice of the opposite sex or within-sex competition for mates, resulting in traits like a peacock's tail or a male gorilla's size and strength. In many animals that lay eggs where female size is a strong predictor of the number of eggs they can lay then natural selection on fecundity can make females larger than males. \n\nSpecies with low-levels of sexual dimorphism have mating systems that don't require males to fight over access to females any more than females fight over males (or access to resources), or where females aren't choosy about who they mate with in visibly obvious ways any more than males are. Though, remember that males and females have to build different phenotypes with mostly the same genome - it's rarely possible for the sexes to evolve their phenotypes completely independently, so there might be a genetic correlation that constrains dimorphism.\n\nThis isn't an exhaustive list of reasons but hopefully you get the idea.\n\nAs /u/jxj24 says, there will always be some level of sexual dimorphism (even aside from primary reproductive structures), and critically enough sexual dimorphism for members of the same species to tell the two sexes apart."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1s76gj
|
free radicals, oxidative stress, and anti oxidants.
|
Always been curious about this.. and how it effects humans.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1s76gj/eli5_free_radicals_oxidative_stress_and_anti/
|
{
"a_id": [
"cdux734"
],
"score": [
2
],
"text": [
"Oxygen is a corrosive gas. It literally steals electrons from other atoms (ie oxidizes them). Our body uses oxygen this way to forcefully pull electrons through several chemical reactions, such as breaking down digested carbohydrates into biochemical energy. This is why you breathe.\n\nUnfortunately, oxygen doesn't care which atoms it steals electrons from. It may steal from a protein or chunk of DNA that causes the victim molecule to no longer function correctly. Worse, the victim molecule is now unstable - it wants to either gain an electron back, or it needs to lose a second electron to become stable again. So now the victim molecule has become the predator, looking to prey on yet another molecule, and this cycle of electron violence continues. Sooner or later, molecules will become so \"broken\" that they can't function... proteins can't do their job, DNA becomes corrupted, etc. Then the cell's functioning starts to break down. If you're lucky (and healthy), your body will recognize the disruption and safely dispose of the cell. If you're not lucky, the faltering cell may become cancerous.\n\nAntioxidants are various chemicals that can neutralize this effect to some extent, thereby preventing damage.\n\n"
]
}
|
[] |
[] |
[
[]
] |
|
1szzhg
|
how do other websites use reddit's content without backlash?
|
There are tonnes of websites that use Reddit user content for posts i.e. Buzzfeed, _URL_0_, theChive etc. Does this mean Reddit is selling their content, or that employees of those websites constantly trawl Reddit for interesting posts? Isn't user content the OP's intellectual property? Is it ok as long as the website attributes the post to the OP? I'm confused.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1szzhg/eli5_how_do_other_websites_use_reddits_content/
|
{
"a_id": [
"ce2y613"
],
"score": [
3
],
"text": [
"It depends on what kind of content you are talking about.\n\nFirst there is the question about what is and what isn't covered by copyright, and also who would own said copyright. Take something like memes. It could be argued that most memes do not reach the level of originality needed, and therefor is not covered by copyright. \n\nIn addition to that, it could be argued that the copyright actually belongs to the creator of the actual image (the producer of the movie, game or whatever it is taken from), and not the person who adds the text.\n\nWhen it comes to content that definitely is copyrighted (such as original images and stories) it largely comes down to the very small risk they take. Most people will not ask Buzzfeed for example to take down content. The few times that someone do send copyright claims to these websites, they simply remove the infringing content and everything tend to be fine. \n\nIt's generally not worth it for a copyright holder to pursue any kind of compensation, due to it taking more time, money and effort then you would actually receive in compensation."
]
}
|
[] |
[
"Cracked.com"
] |
[
[]
] |
|
123r7i
|
What would happen if you could get rid of the Higgs bosons in an object?
|
Me and my friend were wondering the other day in AP physics, what would happen if you could somehow just get rid of all of the Higgs bosons in an object? To the best of my knowledge, the Higgs boson is what gives particles mass, so we assumed that our hypothetical object wouldn't feel the effects of gravity, so our first thought was that it would float around kind of like things in space. Then it occurred to us that the property of inertia is tied to mass, so, since this object would theoretically be without mass, we thought it might just sit where it was, unable to be acted upon. Anyway, for those with a level of physics knowledge deeper than high school can provide, what WOULD happen to our hypothetical object?
|
askscience
|
http://www.reddit.com/r/askscience/comments/123r7i/what_would_happen_if_you_could_get_rid_of_the/
|
{
"a_id": [
"c6rwlef",
"c6s0r4n"
],
"score": [
3,
2
],
"text": [
"The Higgs boson does not give particles mass. There are not Higgs bosons inside ordinary matter.\n\nThe Higgs mechanism is associated with the default value that the Higgs field takes throughout space. The Higgs boson arises as a sort of deviation of the Higgs field from its default value.\n",
"There aren't Higgs bosons *in* an object. The mass of matter is related to the extent to which the matter interacts with the Higgs bosons/field.\n\nThe vacuum of space is essentially filled with something known as the Higgs field, named after the eponymous physicist Peter Higgs, one of the people who developed this idea in 1964. This field interacts with the particles passing through it. They begin to slow down and bind together, forming complex structures such as protons, nuclei, atoms, and molecules. \n\nYou can think of the particles of the Higgs field as a line of defenders in a football game. Without them, all the matter in the universe would freely travel at the speed of light, just as the ball carrier would easily score touchdown after touchdown. But *with* the Higgs defenders present, the ball carrier is slowed down significantly. In the same way the defenders slow down the running back, the Higgs field slows down particles as they travel through it. \n\n[ ^^ damn near direct quotes from a planetarium show I wrote about the LHC/Higgs/dark matter/the Big Bang ^^ ]"
]
}
|
[] |
[] |
[
[],
[]
] |
|
232en9
|
why are steel surfaces relatively inhospitable to bacteria and other germs whereas stuff like acrylic are not?
|
I use an electronic cigarette which uses mouthpieces that can be swapped out. These come in a variety of materials, from acrylic to delrin to plastic to aluminium to steel to copper to wood.
The second-hand market for these are small to begin with, but it's almost unanimously understood you shouldn't buy acrylic, plastic, delrin, or wood second-hand, it poses a sanitary concern. Metal mouthpieces are fine, though.
Is this because bacteria cannot live on steel or other metals very long, and if so, why?
edit:
I wanted to add that I know copper is a natural antimicrobial. I work in a field preparing consumables, and copper plated steel tables are the norm, since they're very clean and remain clean. I know why copper is inhospitable to bacteria, but not why steel or other metals are.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/232en9/eli5_why_are_steel_surfaces_relatively/
|
{
"a_id": [
"cgsroou",
"cgt14on"
],
"score": [
5,
2
],
"text": [
"I believe it has to do with the surface and how porous it is/isn't. Bacteria need tiny holes to hang out in (which also traps stuff they feed on), otherwise they get brushed away easily and there is less available 'food' for them. Also some metals give off ions that apparently kill bacteria. I know silver does, not sure about other metals.",
"It's known that certain metals like silver and copper possess metal ions that are toxic to a wide range of organisms. This is called the [Oligodynamic effect](_URL_0_) which Wikipedia further defines as \"a toxic effect of metal ions on living cells, algae, molds, spores, fungi, viruses, prokaryotic and eukaryotic microorganisms, even in relatively low concentrations. This antimicrobial effect is shown by ions of mercury, silver, copper, iron, lead, zinc, bismuth, gold, aluminium, and other metals.\" \n\nAs far as I know the exact nature of this effect is not very well understood. There are some descriptions of specific interactions the ions have on metabolic functions that are disruptive however I'm no biologist so I'm afraid I can't ELI5. Here's another [source](_URL_1_) if you'd like to go into further detail on this phenomenon. \n\nHope this helps.\n\nEDIT: Just saw OP's edit. My bad. I guess you already knew that copper had this property. I guess my revised answer to you would be it appears that several other metals exhibit this antibacterial effect as well including iron and iron alloys like steel but not nearly as well as copper. "
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Oligodynamic_effect",
"http://www.tested.com/science/life/453961-oligodynamic-effect-how-some-metals-kill-bacteria/"
]
] |
|
89yfpi
|
why does visible heat* have a shadow if it isn’t causing an absence of light?
|
*the kind of heat waves you see rising from a radiator or the ground on a hot day that seem to shimmer.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/89yfpi/eli5_why_does_visible_heat_have_a_shadow_if_it/
|
{
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"dwufk73",
"dwufkkd",
"dwuwddf",
"dwv4h5q"
],
"score": [
30,
6,
9,
3
],
"text": [
"When air gets hot, it changes the density so you have swirling patches of hotter & cooler air.\n\nAir of different densities passes light differently, creating those shadows.",
"Heat wave changes the density of its surrounding medium. Therefore refraction occurs as light passes through a medium going from 1 density into another.",
"Like others have said, its because the hot/cold air mixture distorts the image by bending transmitted light. \n\nFun side fact, mirages are also caused because of this phenomenon. Except that in mirages, air gets hotter and hotter as you get closer to the ground so the incoming light from a distance straight in front of you keeps bending as it gets closer to the ground until it becomes parabolic so you get the illusion of a reflection.\n\n",
"Nothing is blocking the light, rather the light is just being bent off-course by higher and lower densities of air, and is landing somewhere else."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
7lk6yo
|
why do car windows get a grid pattern on them
|
So what I mean is, I’ve noticed on some rear windscreens what looks like squares of condensation in between the heating elements of the back window. Naturally I assumed it was because of those heating elements, however I also get in on my side windows too when I’ve had the heating on. What cause it
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7lk6yo/eli5_why_do_car_windows_get_a_grid_pattern_on_them/
|
{
"a_id": [
"drmyxik",
"drnauwp"
],
"score": [
225,
12
],
"text": [
"Whenever the glass is rapidly cooled during the tempering process there are these air jets that blow cool air on the glass. This creates distortions in the glass that are almost invisible, until you put on polarized glasses. Different automakers have different (patented) patterns or cooling methods to reduce this distortion. ",
"Tempered glass has stressors built-in. You can see them with polarized sunglasses. The built-in stress is what causes the window to completely shatter into small pieces when the window is damaged in any way. Even a scratch may cause enough damage to shatter the window."
]
}
|
[] |
[] |
[
[],
[]
] |
|
ney9s
|
How does evolution increase biological complexity?
|
I understand natural selection perfectly well, with (f.x) the fastest horses being selected to survive, etc.
But does this process transfer to increasing complexity?
As an example, it makes sense that a horse with (Lets imagine) 255 genes could eventually have ancestors with a more ideal (for survival) arrangement of these genes.
But how do you go from a single-cell organism to a complex animal, just something as relatively "simple" as an insect or small fish?
|
askscience
|
http://www.reddit.com/r/askscience/comments/ney9s/how_does_evolution_increase_biological_complexity/
|
{
"a_id": [
"c38jsqb",
"c38kzji",
"c38jsqb",
"c38kzji"
],
"score": [
2,
2,
2,
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"text": [
"Your 'relatively simple' example is actually perhaps the most complex; the jump from single to multiple cell is probably the most significant. Hence why it took so long (something in the order of a couple of billion years). From there on it's just a case of structural specialisation.\n\nEvolution is simply the expression of a small proportion of genetic mutations being favoured. We don't know the exact route for any of the above, as we don't have the vast majority of the intermediary species to analyse. It's like trying to know the precise movement of a person in a 24 hour period when all you have is a dozen photos taken at random intervals.\n\nBut to answer your question as broadly as possible, if you have a single cell, and a single cell which has a mutation which has developed an extra, tougher outer surface, the second cell is more likely to survive hostile environments, and also more complex than the first. Now follow through on tiny changes (most even less significant than that one) trillions of times, over several billion years and hey presto, you have a talking ape sat at a machine it built, leaving a message for a similar talking ape somewhere else on the planet.",
"\\1. Genetically complexity increases by duplication followed by divergence.\n\nThat is parts of the genome get copied and possibly moved at the same time. And then they change from the original.\n\n\\2. From unicellular to multicellular goes via communities that benefit from living together, it's not that unlike the evolution of eusociallity in insects and some other animals.\n\nin social groups like those only the queen (or equivalent) reproduces and is kind of a meta version of only the sex cells in a multicellular organism reproducing.\n\nin these cases (and in multicellular organisms) the others \nactually get *more* of their genes into future generations by *helping* the sex animals/cells reproduce than by trying to do it themselves - ie they form themselves into a more efficient \"reproduction factory\".\n\nedit:\n\nYou could think of it like forming a bucket brigade to fill a pond with some of your genes.",
"Your 'relatively simple' example is actually perhaps the most complex; the jump from single to multiple cell is probably the most significant. Hence why it took so long (something in the order of a couple of billion years). From there on it's just a case of structural specialisation.\n\nEvolution is simply the expression of a small proportion of genetic mutations being favoured. We don't know the exact route for any of the above, as we don't have the vast majority of the intermediary species to analyse. It's like trying to know the precise movement of a person in a 24 hour period when all you have is a dozen photos taken at random intervals.\n\nBut to answer your question as broadly as possible, if you have a single cell, and a single cell which has a mutation which has developed an extra, tougher outer surface, the second cell is more likely to survive hostile environments, and also more complex than the first. Now follow through on tiny changes (most even less significant than that one) trillions of times, over several billion years and hey presto, you have a talking ape sat at a machine it built, leaving a message for a similar talking ape somewhere else on the planet.",
"\\1. Genetically complexity increases by duplication followed by divergence.\n\nThat is parts of the genome get copied and possibly moved at the same time. And then they change from the original.\n\n\\2. From unicellular to multicellular goes via communities that benefit from living together, it's not that unlike the evolution of eusociallity in insects and some other animals.\n\nin social groups like those only the queen (or equivalent) reproduces and is kind of a meta version of only the sex cells in a multicellular organism reproducing.\n\nin these cases (and in multicellular organisms) the others \nactually get *more* of their genes into future generations by *helping* the sex animals/cells reproduce than by trying to do it themselves - ie they form themselves into a more efficient \"reproduction factory\".\n\nedit:\n\nYou could think of it like forming a bucket brigade to fill a pond with some of your genes."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
e3ti4b
|
how does opening new lines of credit *help* your credit score?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/e3ti4b/eli5_how_does_opening_new_lines_of_credit_help/
|
{
"a_id": [
"f94uxvx",
"f94x493"
],
"score": [
2,
2
],
"text": [
"It increases your cap making it easier to maintain a lower percentage use of your overall credit. Lower overall use increases your score.",
"Your credit score is really, really important. It’s a measure of how worthy of credit you are considered, and you’re going to need a good score for a lot of different things. In order to have a good credit score, you’re going to need a credit history. A lot of people think if they have no credit cards or debt, they automatically have a good score but that’s not true. If there is no record of how you handle credit, no one knows if you deserve a good score or not. So, opening a line of credit—and handling it responsibly—will give you a good credit score. The more lines of credit you have the greater is your overall available credit. For instance, if you have three credit cards with a credit limit of $5,000 each you have $15,000 of available credit. If your total balance over all of these cards is $500.00, you are only utilizing 3% of your available credit. That’s a good percentage and it shows that you don’t overuse your lines of credit. Alternatively, if you have a total balance of $14,000 you are using 90% of your available credit, and that’s not good. It shows you are likely to just run up your balance, and makes you a risk for defaulting on your lines of credit.\n\nSo, the more lines of credit you have the more you have demonstrated how many creditors are willing to extend you credit. That’s good. And the more available credit you have, the greater your opportunity to NOT overuse it, which shows you are responsible. \n\nAlso, a big part of your credit score is the age of your oldest line of credit. That shows you have responsibly handled that available credit for a long time without defaulting or having the account closed."
]
}
|
[] |
[] |
[
[],
[]
] |
||
35vjio
|
can a communist economy work with a democratic system?
|
Through history we've seen most communist nations fail because they had shitty dictators and a shitty political system. Could a communist economic system work if the politics of that system were democratic(more or less)?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/35vjio/eli5can_a_communist_economy_work_with_a/
|
{
"a_id": [
"cr8907r",
"cr8bvpq"
],
"score": [
3,
2
],
"text": [
"Ideally, all communist nations are democratic, since the idea is that everyone works towards a common goal and everyone is equal. Post- Stalin USSR and post- Mao China were/ are democratic, in that you can vote for the leader. There's only one party, however so this winds up being a choice between John Anderson and Anders Johnson. \n\nCommunism ultimately fails because the core idea is a group of people working their hardest for the betterment of all. This can work for a group of 20 people, but when you have 20 million (or even 20 thousand) that's just not going to happen.",
"yes it can, that's functionally what socialism is. Of course, not to extremes that \"communism\" entails, but, yknow.\n\nYou elect representatives democratically, to make the decisions you support, in terms of doling out \"public\" assets, which in many countries includes health care, or controlling banks and insurance, cars, other regulatory things that corporations shouldn't be allowed to control, because these things that are part of our everyday life should be governed by who the people say should govern.\n\nas opposed to capitalism, which results in the idea that that corporations shouldn't be controlled by regulations from the government, thus are \"privatized\", and controlled by themselves and that often results in them doing freely whatever earns them more money nomatter how much it fucks over other people- their interest is getting money, or \"capital\", and that is what drives their decisions. Privatizing things that are vital to everyday functional life in a first-world country, healthcare, insurance, banks etc, shouldn't be privatized. In capitalism, however, they're free to be, and therefore what ends up happening is that they are not controlled by people the citizens elect to represent them... they're controlled by whoever the hell is the CEO.\n\nSome people spin this as being good, because these corporations have 'freedom', or whatever, but I've never heard a good argument for it before... there's always some element missing. \n\nCapitalism can be very, very beneficial to growing economies, specifically third-world countries that need to establish an economy. But when you reach a level where your people aren't in danger of dying or starving and you can drift towards socialism, which is what virtually every superpower in the whole world has... except for the US. I could go into that, but... that's a different question. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
1zdw6c
|
is there an easy explanation or visual for the organization of the us army?
|
All the sources I've looked at are hard to understand. My grandfather was in the army (Major General) and he always told me these stories with terminology I never understood so it'd be nice to have it explained simply.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1zdw6c/eli5_is_there_an_easy_explanation_or_visual_for/
|
{
"a_id": [
"cfss3y6",
"cftaxfa"
],
"score": [
2,
2
],
"text": [
"Organisation of ranks? Organisations of armies, corps, divisions, battalions, etc? There's lots of things that fall under this question. ",
"*nice try, Russia*"
]
}
|
[] |
[] |
[
[],
[]
] |
|
ol0ov
|
If I smell a strong scent while eating, does it influence how I taste the food?
|
I smelled a scented candle today while I was eating instant oatmeal and I believe it may have changed how I tasted the oatmeal.
|
askscience
|
http://www.reddit.com/r/askscience/comments/ol0ov/if_i_smell_a_strong_scent_while_eating_does_it/
|
{
"a_id": [
"c3i50zz"
],
"score": [
2
],
"text": [
"You only have five basic tastes: sweet, sour, salty, bitter and umami. Everything else is smell, which is why things taste bland when you're congested."
]
}
|
[] |
[] |
[
[]
] |
|
2glaao
|
French (or Allied) perspective of WWI trenches
|
Many people have read or heard of "All is Quiet on the Western Front." Is there a similar famous work that provides the French perspective of the Great War? In addition are there any particularly noteworthy memoirs of French (or Allied) soldiers during WW1 that historians might recommend?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2glaao/french_or_allied_perspective_of_wwi_trenches/
|
{
"a_id": [
"ckk9id4",
"ckkd4xx",
"ckkh5zs"
],
"score": [
4,
4,
7
],
"text": [
"You could try Charles Carrington's A Subaltern's War or Guy Chapman's A Passionate Prodigality or Robert Graves Goodnight To All That.\n\nI'm afraid these are British (and may be hard to come by), I don't know of any French ones.\n\nAlso, since its the centenary, quite a lot of diaries have been uploaded to sites like this, some of which are quite interesting:\n\n_URL_0_\n\nAs to Remarque - Its worth bearing in mind that Remarque was a sapper and only saw a couple of weeks action on the front. \n\nAll is Quiet on the Western Front is by no means a memoir or a biography, it is a novel and an anti-war polemic. \n\nIts worth contrasting Remarque with the books of actual \"front line\" soldiers who served in the German army for most of the war - Rommel's Infantry Attacks and Ernst Junger's Storm of Steel are good examples and quite readily available.\n\nBon Chance.",
"I really enjoyed [this book] (_URL_0_). Read a Dutch translation about 10 years ago but i am reading it again.\n\nLouis Barthas, the writer, was called up in 1914 and survived the entire war. He fought at Verdun, the Somme, Champagne and The Argonne. \n\nAnyway, great read. The reviews on amazon should tell you enough. ",
"[*Under Fire*](_URL_0_) was a novel written by the Frenchman Henri Barbusse, and was actually published *during* the War, in 1916. *Under Fire* is technically not a memoir, but rather, is a work of fiction, with an unnamed narrator. However, it is pretty clearly influenced by Barbusse's time on the frontline. Barbusse's political biases (he was a Communist) also can shine through, but overall it is a rather short read that is definitely quite interesting. Regardless of how true the events in *Under Fire* actually are, the stories in it do lineup with accounts of the Great War that I've read from British and German sources and if nothing else the novel itself is worth reading because it is such an anomaly, being an anti-war novel published as the War was still going on. Basically, it shouldn't be taken as straight history, but it is of historical value."
]
}
|
[] |
[] |
[
[
"http://firstworldwar.com/diaries/index.htm"
],
[
"http://www.amazon.com/Poilu-Notebooks-Corporal-Barrelmaker-1914-1918/dp/0300191596"
],
[
"http://www.amazon.com/Under-Penguin-Classics-Henri-Barbusse/dp/0143039040/ref=sr_1_1?s=books&ie=UTF8&qid=1410920186&sr=1-1&keywords=under+fire+barbusse"
]
] |
|
2tkszs
|
Is there a part of the brain that controls the perception of time?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2tkszs/is_there_a_part_of_the_brain_that_controls_the/
|
{
"a_id": [
"co0mr5u"
],
"score": [
3
],
"text": [
"Great question, and the simple answer is that many different parts of the brain help you to perceive time... because time is crucially important for many types of behaviors we engage in.\n\nOne area of the brain, the [suprachiasmatic nucleus \\(SCN\\)](_URL_0_) affects circadian rhythms -- tracking day and night cycles. Other areas of the brain,[ like the cerebellum](_URL_2_), help time fine motor movements and may control timing on the order of seconds. The [basal ganglia](_URL_1_) (implicated in motion and some learning processes) and other areas of the cortex may also have some role in keeping time on different scales and relating to different processes.\n\nAnother interesting way of looking at this is how our perception of time is tied to memories, which would implicate the hippocampus and associated cortex. In some cases where people have profound amnesias, their sense of past, present, and future are severely distorted, but they still have the ability to time short-term processes correctly. So, when you think about the different scales of time from milliseconds to decades, there are different processes that rely on different kinds of timing and probably work together to form a coherent \"flow\" of time. \n\nAnyhow, I'm sure I didn't answer your question... but I think there is no one single answer... just like I believe most people would agree there's no single part of the brain that controls our time perception. :)\n\n"
]
}
|
[] |
[] |
[
[
"http://thebrain.mcgill.ca/flash/d/d_11/d_11_cr/d_11_cr_hor/d_11_cr_hor.html",
"http://www.sciencedirect.com/science/article/pii/0926641096000092",
"http://psych.concordia.ca/fac/penhune/publications/penhune_JCN_98.pdf"
]
] |
||
2ucg1d
|
why do we not all adopt a race-nationality identification like african-american (ex. asian-australian)?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2ucg1d/eli5_why_do_we_not_all_adopt_a_racenationality/
|
{
"a_id": [
"co740s0",
"co744i1"
],
"score": [
3,
4
],
"text": [
"what would be the purpose of this? except to further create race/ethnicity issues. ",
"It's too broad. Under that you could say I'm a European-American, but to be honest I don't really see myself as European at all despite my ancestry. I just wish we didn't classify race at all and just went by nationality. If you are a US citizen, you are an American. If you are an Australian citizen, you are Australian, etc. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
664iv4
|
why are hand dryers in public restrooms considered more hygienic than paper towels? having forced air blowing germs all over the place doesn't seem very hygienic at all.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/664iv4/eli5_why_are_hand_dryers_in_public_restrooms/
|
{
"a_id": [
"dgfici6",
"dgfivox"
],
"score": [
8,
3
],
"text": [
"It turns out that you are correct. Not only do they blow germs from outside the blower... What happens when someplace is dark, warm, and moist? Mold grows. So you're getting mold spores and waste from INSIDE the dryer on your hands, too.\n\n_URL_0_\n",
"I feel like they might do it because it's less of a hassle than switching out paper towels constantly. \nI'm probably wrong but, my first thought. "
]
}
|
[] |
[] |
[
[
"http://www.webmd.com/a-to-z-guides/news/20141121/restroom-hand-dryers-spread-more-germs-than-paper-towels-study-finds"
],
[]
] |
||
smlbo
|
the different divisions of the nervous system.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/smlbo/eli5_the_different_divisions_of_the_nervous_system/
|
{
"a_id": [
"c4f8bnx"
],
"score": [
2
],
"text": [
"The Nervous System(NS) is composed of 2 major divisions which are: \n\n(1) **The Central NS**; which is made up of the brain and the spinal cord. They are *both enclosed in bony structure* (skull and vertebra) because of their importance. They control either voluntarily or involuntarily almost all body functions and interpret all sensory inputs of the body. That includes moving a single muscle or telling the difference between red or blue. The difference between the 2 is that the brain commands and monitors while the spinal cord is a \"brain tail\" which clumps all of the tracts(big bundled nerves) for the rest of the nervous system to connect to.\n\nThe brain can be likened to a central computer in a modern house, which controls and monitors everything from a single area. While the spinal cord is the main cable in which most cords are connected to. In this house every gadget or security monitors are linked to a single computer.\n\n(2)**The Peripheral NS**; this meanwhile *connects the rest of the body to the brain and spinal cord*. Unlike the CNS, they are made up mostly of **tracts of nerves** bundled together and so has no bony structure protecting it. They send signal both ways from the brain to an organ **or** from an sensory/organ up to the brain. This can be compared to the cables that connects all the gadgets, appliances, or monitors to the central computer of the house.\n\nThe nerves of the PNS has 2 types: \na. *the cranial nerves*, a nerve which connects the brain directly to an organ. An example would be the optic nerve, which sends visual signals directly to the brain. We all have 12 pairs of these. All our special senses (smell, hearing, taste) muscles of face are connected by cranial nerves.\nb. *the spinal nerve*, long nerve which connects the muscles of our arms to the spinal cord which relays the signal to the brain. We have 31 pairs of these, a pair sprouting from the junction of two vertebra(spinal bone). The rest of our body is connected to the brain this way.\n\nThe PNS also has 2 major types of Autonomous(NS) or involuntary body control, they are:\n1. Sympathetic NS; \"fight or flight\" response, responsible for taking over body functions during stressful situations. Makes your pupils bigger, to see better. Makes your heart pump faster, to cope with increase energy usage. Or slows digestion.\n2. Parasympathetic NS; \"rest and repair\", does the complete opposite of sympathetic NS. Increases rate of digestion, slows heartrate etc. \n\n "
]
}
|
[] |
[] |
[
[]
] |
||
e5i60m
|
How do mitochondria change their internal proton count to initiate electron chain transfer ?
|
askscience
|
https://www.reddit.com/r/askscience/comments/e5i60m/how_do_mitochondria_change_their_internal_proton/
|
{
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3,
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"text": [
"By that, I assume you’re talking about the proton gradient? In which case the ions cross the complexes that are in the inner membrane, and move into the inter membrane space. Those ions of course come from the NADH that oxidate into NAD+ when the come in contact with the complexes, passing their electrons and their hydrogen ions into the complexes.",
"I'm not sure what you mean by this. Mitochondria are the site of [oxidative phosphorylation](_URL_2_), which uses the oxidising power of oxygen to extract chemical potential energy from food, primarily in the form of glucose. The two main processes that metabolise glucose are [glycolysis](_URL_3_) and the [citric acid cycle](_URL_0_). Glycolysis takes place in the cytoplasm, consuming 2 NAD^(+) \\+ 2 ADP + 2 phosphate while producing 2 pyruvate + 2 NADH + 2 ATP as key metabolic products:\n\nC₆H₁₂O₆ + 2 NAD^(+) \\+ 2 ADP^(3–) \\+ 2 HPO₄^(2–) ⟶ 2 CH₃C(O)COO^(–) \\+ 2 NADH + 2 ATP^(4–) \\+ 2 H^(+) \\+ 2 H₂O\n\nPyruvate then undergoes oxidative decarboxylation by [pyruvate dehydrogenase](_URL_1_) to give acetyl-CoA, consuming NAD^(+) and generating NADH in the process:\n\nCH₃C(O)COO^(–) \\+ HS–CoA + NAD^(+) ⟶ CH₃COS–CoA + CO₂ + NADH\n\nAcetyl-CoA then enters the citric acid cycle, where the acetate bit is fully oxidised to carbon dioxide through a series of reactions. The net reaction is as follows:\n\nCH₃COS–CoA + 3 NAD^(+) \\+ UQ + GDP^(3–) \\+ HPO₄^(2–) \\+ 2 H₂O ⟶ HS–CoA + 3 NADH + UQH₂ + GTP^(4–) \\+ 2 H^(+) \\+ 2 CO₂\n\nUQ is ubiquinone, which plays a role in the electron transport chain (we'll get to that later). The overall reaction so far can be summarised as follows:\n\nC₆H₁₂O₆ + 10 NAD^(+) \\+ 2 UQ + 2 ADP^(3–) \\+ 2 GDP^(3–) \\+ 4 HPO₄^(2–) \\+ 2 H₂O ⟶ HS–CoA + 10 NADH + 2 UQH₂ + 2 ATP^(4–) \\+ 2 GTP^(4–) \\+ 6 H^(+) \\+ 2 CO₂\n\nThat's all well and good, but we know the overall reaction for glucose metabolism should be much simpler:\n\nC₆H₁₂O₆ + 6 O₂ ⟶ 6 H₂O + 6 CO₂\n\nSo far we have said nothing about oxygen. This is where the electron transport chain comes in: it provides a biochemical pathway to harness the energy released when oxygen is reduced to water. Through a series of electron transfer reactions involving several enzymes, this reduction is coupled to the oxidation of NADH and UQH₂, which regenerates NAD^(+) and UQ.^(1) The energy released by these reactions is used to transport H^(+) from the mitochondrial matrix to the intermembrane space, creating a pH gradient across the inner membrane. I am not sure of the exact mechanism each enzyme uses to transport H^(+), but broadly speaking conformational changes in the protein throughout the reaction are what drive translocation of H^(+). Some electron transfers are additionally proton-coupled, and the enzymes involved are arranged such that the matrix is depleted of H^(+) and vice versa for the intermembrane space. The difference in chemical potential created by this pH gradient is harvested by ATP synthase as H^(+) diffuses back across the membrane, driving the synthesis of ATP from ADP and phosphate.\n\nIn short, to answer what I think is your question, the electron transport chain *creates* the pH gradient, not the other way around.\n\n^(1) This isn't quite the whole picture as UQ/UQH₂ is part of the electron transport chain itself, and the enzyme that reduces UQ to UQH₂ is itself part of the citric acid cycle."
]
}
|
[] |
[] |
[
[],
[
"https://en.wikipedia.org/wiki/Citric_acid_cycle",
"https://en.wikipedia.org/wiki/Pyruvate_dehydrogenase_complex",
"https://en.wikipedia.org/wiki/Oxidative_phosphorylation",
"https://en.wikipedia.org/wiki/Glycolysis"
]
] |
||
5wrtwd
|
why couldn't giant mirrors (like the entire industrialized world focusing on producing giant mirrors) eradicate global warming by reflecting the suns rays for a while?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5wrtwd/eli5_why_couldnt_giant_mirrors_like_the_entire/
|
{
"a_id": [
"dech8jz"
],
"score": [
2
],
"text": [
"How would you make those mirrors?\n\nIn some kind of industrial plant, right?\n\nAnd to smelt all that glass you'll need some big natural gas burners.\n\nAnd you'll burn a lot of it which will produce an extraordinary amount of carbon in the atmosphere.\n\nWhen you're all done you'll have some great mirrors. But mirrors reflect light, not heat. In fact, those mirrors are going to get really hot because they are receiving all the radiation from the sun.\n\nSo, unfortunately, your solution compounds the problem. It would be far less difficult to simply conserve energy and reduce fossil fuel use."
]
}
|
[] |
[] |
[
[]
] |
||
187w20
|
How did powerful families come by their power in the first place?
|
How were families like the House of Plantagenet, the Rothschilds, Tudors, etc able to come by their power or initial source of wealth and eventually grow into those powerful and influential families? Where did the first Rothschild get his initial cash to start loaning money? Why did the Tudors stand out from everyone else and become a ruling family?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/187w20/how_did_powerful_families_come_by_their_power_in/
|
{
"a_id": [
"c8ce9gu"
],
"score": [
6
],
"text": [
"I can't talk about the Rothschilds or the like, but I certainly can talk about [the Tudors](_URL_5_) and [the Plantagenets](_URL_1_) and the like. \n\nHenry Tudor, who became King Henry VII of England, of the House of Tudor, was the victor of the [the Wars of the Roses](_URL_3_) between the House of Lancaster and the House of York, who both claimed to be legitimate heirs to the throne. He was *already* in a powerful family - he was just in one branch of it (Lancaster), and defeated the other branch (York). He then married a York woman, combining the two families, and ended the conflict that way.\n\nAnd, the Houses of Lancaster and York were both descendants of the Plantagenets. And, the Plantagenets were just descendants of William the Conqueror, who defeated the King of England in 1066, and declared himself King. \n\nBut, even then, William was already in a powerful family - he was Duke of Normandy, which was a [noble role created by King Charles III of France](_URL_4_). And, the kings of France trace their power back to [the Merovingian kings](_URL_0_), who started out by [conquering some tribes around them](_URL_2_).\n\nMost monarchs trace their origins of power back to an original warrior or chieftain who simply overpowered the people around him and took charge. They became leaders by force. All subsequent conflicts and transfers of power were traceable back to that original chief who took charge. There have been very few monarchs who didn't get their power either by conquest, or by being descended from (or *claiming* to be descended from) conquerors.\n"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/List_of_French_monarchs#Merovingian_Dynasty_.28428.E2.80.93751.29",
"http://www.reddit.com/r/AskHistorians/comments/16i7z3/a_question_on_the_ruling_houses_of_england/c7wcu6w?context=3",
"http://en.wikipedia.org/wiki/Merovingian#Origins",
"http://en.wikipedia.org/wiki/Wars_of_the_Roses",
"http://en.wikipedia.org/wiki/Duke_of_Normandy",
"http://www.reddit.com/r/AskHistorians/comments/17wzda/is_the_house_of_windsor_related_to_the_house_of/c89lglq"
]
] |
|
1ptsiv
|
Sibling birth order: does it affect anything?
|
Longevity. Incidence of specific diseases. Mental illness. Career path and success. Does being the older/younger/middle sibling effect anything of the above or anything on these lines?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1ptsiv/sibling_birth_order_does_it_affect_anything/
|
{
"a_id": [
"cd63iqk",
"cdlvcvf"
],
"score": [
6,
2
],
"text": [
"The only thing I know of is the potential link between fraternal birth order and male sexual orientation.\n\n_URL_0_\n\n > In several studies, the observation is that the more older brothers a man has, the greater the probability is that he will have a homosexual orientation.[1] It has sometimes been called the older brother effect. It has been estimated that 15% of the homosexual demographic is associated with fraternal birth order.\n\nThe article also cites some contrary evidence, so it seems the theory may be rather controversial.",
"Other than sexual orientation, I can't recall anything it influences. It doesn't influence IQ, once you use the proper methodology. [(Wichman, et al., 2006).] (_URL_0_) \n\nIn general, I would be very skeptical of any claims that relate to birth order. In general, claims like that are the product of extrapolation. In the case of IQ and birth order, researchers used cross-sectional studies, where they compared IQ and birthorder between families, instead of using longitudinal studies where they could examine the effect within families across time. \n\nSource: Wichman, A. L., Rodgers, J. L., & MacCallum, R. C. (2006). A multilevel approach to the relationship between birth order and intelligence. Personality and social psychology bulletin, 32(1), 117-127."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Fraternal_birth_order_and_male_sexual_orientation"
],
[
"http://psp.sagepub.com/content/32/1/117.short"
]
] |
|
4y1uyc
|
what's going on in milwaukee ?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4y1uyc/eli5_whats_going_on_in_milwaukee/
|
{
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"text": [
"A young African American man was being pursued by the Police. He displayed and aimed a weapon at the Officer. He was promptly shot. He passed away. The community rioted since their perspective is that any shooting under any condition is unlawful. As it turns out the young man has a record and the gun was stolen.\n\nThat's the facts. But there are many more opinions to go with those facts.",
"Copied from myself in another thread:\n\nThere is a lot of racial tension going on in America right now. This isn't a riot just because one guy got shot, it's the result of a lot of history of discrimination. Let me be perfectly clear: **I am not trying to justify or apologize for the rioters**. Everyone has a responsibility to search for the facts before reacting, especially before reacting violently. They didn't do that. I am not trying to justify the behavior, nor am I taking their side - I'm not trying to take any \"side\". I'm only trying to give insight into the mentality so that even if you disagree with their actions you can be aware of why it happened (and hopefully work to prevent it in the future).\n\nWhile this one instance, by all accounts, appears as though the officer was completely justified, that has not always been the case. Even with Mike Brown, although witnesses eventually demonstrated that there was a fight and that Brown was moving towards the officer, the whole thing was handled poorly. Police weren't very cooperative with the community to find the truth. And there have been a number of incidents where it's pretty clear that the police were out of line. There are also some disturbing statistics, like the fact that minorities are more likely to get jail time, and more likely to get *more* jail time for the same offense. Minorities are also overrepresented in fatal police interactions.\n\nThe overall picture is that racial discrimination absolutely happens, a lot. Some argue that the reason you hear so much about black kids fighting the police is that they don't have any particular reason to believe it'll work out any better for them if they don't. The logic (whether or not it's accurate) is that you'll get shot if you do nothing anyway, so why let them?\n\nThat creates a lot of fear and distrust between police and their communities. The police are afraid that they'll get attacked, so they're more aggressive. The people in the community are afraid they'll get attacked (because, yeah, they will, it keeps happening) so they get aggressive. Which of course confirms the fears of the police, and there's a vicious cycle.\n\nIn Milwaukee, the tension has built up a lot. It's been described as the country's most segregated city, and there's a lot of poverty that is largely along racial divides. The people there don't have a lot of good reasons to trust the police. So when the police shoot someone in that community, their immediate reaction is going to be contrary to law enforcement. They are not inclined to believe that he deserved to get shot because too often that's not the case. All the little interactions that have not been positive from either side finally came to a head and exploded because of the shooting.\n\nTL;DR: the riot isn't really over the shooting, that's just the excuse for the community there to vent decades of racial tension in a destructive way. ",
"Black officer shot black suspect after suspect pointed a gun at the officer. Riots ensue due to racial tension being pushed largely by the media and false ideas, as well as groups who want to use skin color as a reason to be able to commit violence without repercussion. Rioters are from both the area as well as from other communities. Some are even paid to cause disturbances. They burn down businesses having nothing to do with the shooting. Some groups are even targeting white people to attack. It's essentially collectivist tribalism, and racism, all rolled together with no real actual comprehensive change or goal in mind to address the REAL problems. And they are gaining ground because politicians and policies in government are starting to pander to such monsters. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
1n93hn
|
Maximum rotation of a pulsar
|
Is there some maximum rotation speed for a pulsar (that is dependent on size). Where the matter on the surface of the star would be moving faster than the speed of light?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1n93hn/maximum_rotation_of_a_pulsar/
|
{
"a_id": [
"ccgohaw"
],
"score": [
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"text": [
"Speed of light is always a limit, but not here. Here, the limiting factor is the fact that at ~1500 rotations per second, gravitational radiation would release more energy than accretion could compensate. For an average 12km pulsar, that's less than half the speed of light, and even that's pushing it."
]
}
|
[] |
[] |
[
[]
] |
|
1e8xe9
|
Are animals immune to poison ivy?
|
Just curious. On my way to work this morning I saw a squirrel run up a tree which had poison ivy growing all over it. Does it effect animals the same as it does humans?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1e8xe9/are_animals_immune_to_poison_ivy/
|
{
"a_id": [
"c9xz012"
],
"score": [
5
],
"text": [
"Humans are generally allergic to an oil in poison ivy called urushiol. Other animals are not affected, and many actually eat poison ivy. Sources: [1](_URL_1_), [2](_URL_0_)"
]
}
|
[] |
[] |
[
[
"http://www.poison-ivy.org/html/faq.htm",
"http://www.fcps.edu/islandcreekes/ecology/poison_ivy.htm"
]
] |
|
1mhd6y
|
What rate would glaciers be growing or melting without human intervention?
|
From my understanding of history, where I am now in Central Alberta, Canada, there was over 1km of ice over most of the area.
According to most of what I have read/been told, this was as late as 10000 years ago. _URL_1_
_URL_0_
_URL_2_
Here are some early photos of the local glaciers showing the relatively large distances they have shrunk.
My question is what rate SHOULD they be going at? Clearly if virtually the entirety of Canada was covered in a 1km sheet of ice 10000 years ago, there has been a lot of melting in a relatively short time.
I keep thinking, doesn't it make sense that the glaciers would melt faster as they become smaller? Like ice cubes, they take a while to start melting, but as soon as they get to the last little bit, it's gone.
Everyone seems to be worried about the glaciers vanishing, but looking at the history, doesn't that seem inevitable?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1mhd6y/what_rate_would_glaciers_be_growing_or_melting/
|
{
"a_id": [
"cc9c2pq",
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"text": [
"Before I start, I'm no glaciologist, but I can address some of your points and maybe hope that someone more knowledgeable can come along and set me straight if I get anything wrong, and maybe add some sources...\n\nIt's important to realise that *all* glaciers are melting. Due to the huge pressures of the ice, temperature fluctuations and incoming liquid water (from runoff or rain or whatever), there will always be melt from a glacier. Obviously this melt can be increased, and higher temperatures will tend to do that, but the system is very complex.\n\nWhat you're really asking about is glacial retreat. All glaciers accumulate mass and ablate mass (those are technical terms for gaining and losing), but 'want' to be in a state where the rate that these happen at is equivalent.\n\nIf accumulation rate > ablation rate, the glacier will advance. \nIf ablation rate > accumulation rate, the glacier will retreat.\n\nYou can see from this diagram _URL_0_ that *most* glaciers are currently retreating, but that some are actually advancing. This fact alone immediately suggests that the situation is not as simple as \"temperatures are getting hotter therefore glaciers are retreating\".\n\nThe rate of glacial retreat depends on a lot of factors, not just the temperature, but the *general trend* of global glacial retreat is used as evidence of increasing temperatures. However, the real drivers may not be that simple - clearly in some areas the rate of accumulation has increased (i.e. more snowfall). In fact, retreat can be caused either by an increase in ablation (i.e. increased temperatures) or a decrease in accumulation (i.e. lower snowfall (which of course might be caused by increased temperatures, but not necessarily)).\n\nYour point about increased melting as the glacier retreats is not really valid - comparing it to a melting ice cube is not really a valid analogy. For a start, the ice cube's surface area to volume ratio quickly decreases as it melts, which will not really happen with a glacier. Also the bulk temperature of the ice cube will be increasing as a whole so that the internal temperature will be increasing even as the outside melts.\n\nAnd yes, people are worried about glacier's melting, for several reasons. For one, they cover around 10% of the Earth's surface and have a strong albedo effect (though this is not necessarily true for all, e.g. icelandic glaciers which are often covered in volcanic ash) and therefore their loss would cause a temperature feedback effect. But there's also the more direct problems - glacial melt causing flash-floods, loss of drinking water, and many others. We had a talk recently by someone looking at glaciers in the Andes, and they're really worried there. But the loss is not necessarily inevitable. We don't understand how Ice Ages work (and the idea that we are 'due' an Ice Age is fairly regularly trotted out), what causes them or how they cycle, but it's also true that glacial retreat could be an entirely natural process. Evidence suggests that climate change is having an effect though.",
"In the absence of anthropogenic increases in greenhouse gases, we would expect over thousands of years for glaciers generally to advance as Milankovitch-driven cooling pushed us towards a new glacial maximum. Exactly how long that would take and at what rate the glaciers would be advancing is a tricky subject, because it's incredibly difficult to suss out what part of the early increase in CO2 and CH4 many thousands of years ago is due to human activity like deforestation and deliberate creation of wetlands for agriculture ([Ruddiman, 2003](_URL_3_); [Ruddiman et al., 2011](_URL_5_)). This is important because the threshold for glacial advance is very sensitive to the background levels of GHGs, and the \"cut off\" falls within the range that is debatably human caused/not definitively 'pre-human'. \n\nWe can look to past interglacial to glacial maxima transitions, make some assumptions about what the background GHG levels should be absent humans, and try to model the climate forward (e.g. [Tzedakis et al., 2012a](_URL_4_); [Tzedakis et al., 2012b](_URL_0_). Readvance towards a new glacial maximum occurs within ~1500 years if background CO2 levels are ~240 ppm or lower, longer if they're higher. \n\nThis tendency towards gradual cooling in the absence of man-made warming, especially in the Northern Hemisphere higher latitudes, is evident in proxy reconstructions for the past several thousand years (e.g. [Kaufman et al., 2009](_URL_2_); [Marcott et al., 2013](_URL_1_)). "
]
}
|
[] |
[
"http://en.wikipedia.org/wiki/Retreat_of_glaciers_since_1850",
"http://en.wikipedia.org/wiki/Late_Glacial_Maximum",
"http://www.erudit.org/revue/gpq/1999/v53/n3/004844ar.pdf"
] |
[
[
"http://upload.wikimedia.org/wikipedia/commons/9/93/Glacier_Mass_Balance_Map.png"
],
[
"http://www.clim-past.net/8/1473/2012/cp-8-1473-2012.html",
"http://www.sciencemag.org/content/339/6124/1198.abstract",
"http://www.sciencemag.org/content/325/5945/1236.abstract",
"http://link.springer.com/article/10.1023/B:CLIM.0000004577.17928.fa",
"http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo1358.html",
"http://hol.sagepub.com/content/21/5/865"
]
] |
|
a6j4c3
|
why is a p/e ratio called price to earnings and not just price to profit?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/a6j4c3/eli5_why_is_a_pe_ratio_called_price_to_earnings/
|
{
"a_id": [
"ebvbity"
],
"score": [
3
],
"text": [
"Profit can vary wildly from one reporting period to another. So many aspects of business can impact it both positively and negatively. In addition some things might lower profits during only one quarter, which if you only tracked profits might make it seem the company had begun performing poorly. \n\nEarnings are simpler to track, much less subject to manipulation and a more consistent indicator of the direction of a company. "
]
}
|
[] |
[] |
[
[]
] |
||
939pt1
|
how does the internet’s wayback machine work?
|
Sidenote; How much data do the servers need to handle?
Context:
[The wayback machine](_URL_0_) is a website where you can visit previous versions of websites/ deleted threads. Type a site in the search bar, say of a youtube user, choose a time, and see what the page looked like on that day/time
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/939pt1/eli5_how_does_the_internets_wayback_machine_work/
|
{
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"text": [
"Correct me if I'm wrong, but this is how previous projects that were similar worked. They have bots (automated software) that crawl the web looking at different webpages and archiving them. Every time it takes a snapshot of a webpage (usually including its source code and, if I remember right, copies of images as well), it stores it and you can view it later.\n\nMore trafficked websites will have visits from those boots quite a lot more often.",
"The wayback machine is absolute proof: The internet doesn't erase anything. \u0010\u0010\u0010\u0010\u0010\u0010\u0010\u0010\u0010\u0010\u0010\u0010Ever.",
"To answer the second part of your question it's currently about 9.6 petabytes, (a petabyte is 1000 terabytes which is 1000 gigabytes) and in 2009 was growing at a rate of 100 terabytes each month."
]
}
|
[] |
[
"https://archive.org/web/"
] |
[
[],
[],
[]
] |
|
198fu1
|
what is "sequestration" in the context of current events?
|
I found two other questions pertaining to this on ELI5, but one wasn't answered and the other was rather vague. Thanks!
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/198fu1/eli5_what_is_sequestration_in_the_context_of/
|
{
"a_id": [
"c8lrpzn"
],
"score": [
2
],
"text": [
"Basically its been decided that the US has too much debt, were spending too much money. To fix the economy, many think that the US Government has to start paying off some of the debt that it has been racking up. There are two ways to do this, either increase the amount of money that it makes or cut money that it spends. Now there are many ways of making money, but the easiest is raising taxes. Many people dont like this because then they would loose more money from their paychecks (and as a person who is doing his taxes currently, even more once a year). Whichever party is currently in power, if they raised taxes a bunch, would not be in power again for a while come next election. \n\nSo that leaves spending. But what does the government cut? At every point in time somebody said \"This program were paying for? Its super important for X,Y, and Z reasons. Plus it helps employ people who voted for me!\". So its hard to cut some programs, and other programs (like Social Security) have become critical issues for some people. Imagine if you were 64, the minimum retirement age was 65 but then it went up to 72. That make you really mad right? So its hard to mess with that type of stuff. \n\nLastly there is a political reason that makes spending hard. See, Democrats like to have all these programs that help people from falling on bad times. But Republicans feel that people should fend for themselves, and shouldn't be the government's responsibility. So they want to cut all these social (welfare) programs that the Democrats like. BUT the Republicans want to spend money on defense, to make more tanks or whatever and they dont want the Democrats to cut that. So each side really wants to cut the thing that the other likes, but nobody is willing to cut a little out of both or come up with some other strategy. \n\nSo what happened last year was that the US's \"credit card\" hit it's limit (almost). We were about to run out of loaned cash, and Congress had to call up the debt company and ask for more. But some, like many Republicans, wanted to make a stink about it and demand that some money be cut from the budget. Then they would raise the cap. But for the above reasons, nobody could decide what to cut (even though the cap already went up) so it went into sudden death overtime. Basically a group of Republicans and Democrats made a deal and said \"We are going to cut all this stuff, stuff that neither side wants cut, if nobody makes a better deal. Further, we are going to cut deeply and really trim down the budget.\" The idea was that the cuts would be so deep, and cut things that nobody wanted cut (and also raise taxes and a bunch of other stuff), that both sides would finally make a deal. The problem was, it was an election year so nobody did **SHIT** to fix the problem. It was funner to just complain about how it was a problem somebody needed to fix. So the deadline has come and gone and nobody agreed on a better plan, so now these cuts will be applied unless some 11th hour drama gets a new deal passed. "
]
}
|
[] |
[] |
[
[]
] |
|
4z0c0q
|
Did Alexander the Great really fight in every battle and siege he waged?
|
1. I believe Alexander fought 19 battles and waged 12 sieges, is it true that he really fought in every engagement? Did he really ride at the head of his companion cavalry?
2. If it is true, was it expected of generals of the time? What did other commanders and soldiers think of him throwing himself into the gray time and time again? What was he trying to prove by doing it?
3. Do we know about Alexander's skill as a cavalryman and infantryman? What do the sources have to say about his actual fighting ability, was he respected as a soldier?
4. Since his time, have generals attempted to emulate his style of 'heroic' leadership by leading from the front? Or was it always deemed far too risky for leaders to attempt something like that?
5. Lastly, could you list some of the best military accounts/books on Alexander's campaigns?
Thanks.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4z0c0q/did_alexander_the_great_really_fight_in_every/
|
{
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"Alexander the Great by Philip Freeman is a good read. It's directed at laymen and thus is less dry than most strictly academic works. I can only answer for what Freeman's work says, so if he was wrong, I hope someone can post a correction. \n\n1. Yes, according to the sources we have he fought in all the major engagements of his army during his famous campaign eastward. \n\n2. It wasn't *common*, for example Darius (leader of Persian Empire) did not fight with his troops. However among smaller, more tribal states such as the Scythians, the leader would fight with the rest of the troops. According to Freeman Alexander's participation was often crucial to morale. Alexander's army won battles in which they were outnumbered by absurd margins (such as at Gaugamela), as well as won offensive sieges by force on cities that seemed basically unconquerable (Tyre and Gaza). Freeman says that Alexanders gusto and personal participation was what kept morale from breaking when his army stood up against immensely larger forces or extremely impressive/legendary fortresses. Overall though it's certain that it was seen as an act worthy of respect, honor, and greatness. The sources (likely) exaggerate some of the stories in an attempt to embellish Alexander, so it was certainly seen as a positive thing to have bravery and battle prowess in a leader, as opposed to someone like Darius who watched comfortably from the rear. There is something innate in people, especially soldiers, to want to follow the leader charging the enemy king instead of the helpless leader running away.\n\n3. He was trained extensively in horsemanship and fighting, as well as general education, from a young age by his father Philip. His father had access to excellent teachers from the kingdom he had built around Macedon during his life and Alexander is said to have had a host of tutors, Aristotle among them. It's reasonable to assume that he would have been an excellent fighter, and surviving sources of course wouldn't say otherwise. \n\n4. Don't know more about this than the average person. \n\n5. Besides Freeman there are countless academic works. However I would recommend just reading A Life of Alexander by Plutarch, a prominent ancient source, or [this](_URL_0_) compilation of ancient sources. \n",
" > Was it expected of generals of the time? What did other commanders and soldiers think of him throwing himself into the gray time and time again? What was he trying to prove by doing it?\n\nAlexander was the product of a tradition - both Greek and Macedonian - of leading warriors by example. In Greek city-states, this was the only recourse for citizens elected to the generalship to prove that they were worthy of the position; among the Macedonians, rather, it fit into older notions of leisure-class competitive display, in which the man who claimed the right to lead had to prove that he had what it took to deserve the leadership. The outcome was the same. All generals were obliged to lead from the front. It was the best way to inspire the men and to get them to do what they had to do. Indeed, Alexander's alleged obsession with Achilles would have encouraged him to behave in the fashion of Homeric heroes, who were constantly trying to outdo one another in acts of bravery and feats of arms in order to justify and secure their high social status.\n\nEven though the Greeks were aware that the loss of a general could be fatal for an army, even military thinkers still recommended that generals lead from the front, aware that a general who was perceived as cowardly would not be able to get anything done. Greek warriors' preference for the \"soldier's general\", who shared in the hardships of the men and led by example, resulted in a staggering casualty rate for Greek commanders. It's often been remarked that Alexander's survival despite mutliple wounds received in close combat was little short of miraculous. Only in the later Hellenistic period do we see generals (starting with Pyrrhos of Epiros) taking a more managerial approach to battle command.\n\n > Since his time, have generals attempted to emulate his style of 'heroic' leadership by leading from the front?\n\nAs noted above, his style wasn't new; it was the norm for all generals in the Greek world, from elected Boiotians to Spartan kings. However, if anything, Alexander's example made the trend worse. Since the men who filled the power vaccuum after his death derived their status primarily from their military prowess, and the chief way to prove one's military credentials was to emulate the greatest commander ever - Alexander - a lot of the so-called *diadochoi* (Successors) shared the same reckless habit of leading from the front.\n\nPlutarch discusses the matter in detail in the introduction to his *Life of Pelopidas*, a fourth-century Greek general who died in battle:\n\n > For if, as Iphikrates analyzed the matter, the light-armed troops are like the hands, the cavalry like the feet, the hoplites like chest and cuirass, and the general like the head, then he, in taking undue risks and being over bold, would seem to neglect not himself, but everyone, inasmuch as their safety depends on him, and their destruction too. \n\n > Therefore Kallikratidas, although otherwise he was a great man, did not make a good answer to the seer who begged him to be careful, since the sacrificial omens foretold his death; ‘Sparta,’ said he, ‘does not depend upon one man.’ For when fighting, or sailing, or marching under orders, Kallikratidas was ‘one man’; but as general, he comprised in himself the strength and power of all, so that he was not ‘one man,’ when such numbers perished with him. \n\n > Better was the speech of old Antigonos as he was about to fight a sea-fight off Andros, and someone told him that the enemy's ships were far more numerous than his: ‘But what of myself,’ said he, ‘how many ships will you count me?’ implying that the worth of the commander is a great thing, as it is in fact, when allied with experience and valour, and his first duty is to save the one who saves everything else.\n\n > Therefore Timotheos was right when Chares was once showing the Athenians some wounds he had received, and his shield pierced by a spear, in saying: ‘But I, how greatly ashamed I was, at the siege of Samos, because a catapult bolt fell near me; I thought I was behaving more like an impetuous youth than like a general in command of so large a force.’\n\n > For where the whole issue is greatly furthered by the general's exposing himself to danger, there he must employ hand and body unsparingly, ignoring those who say that a good general should die, if not of old age, at least in old age; but where the advantage to be derived from his success is small, and the whole cause perishes with him if he fails, no one demands that a general should risk his life in fighting like a common soldier. \n\nOne of the most interesting works on Greek command is E.L. Wheeler's 'The General as Hoplite', in V.D. Hanson (ed.) *Hoplites: The Classical Greek Battle Experience* (1991).\n\nEdit: added Plutarch quoting me"
]
}
|
[] |
[] |
[
[
"https://play.google.com/store/books/details?id=IvP_tHPTZfkC&source=productsearch&utm_source=HA_Desktop_US&utm_medium=SEM&utm_campaign=PLA&pcampaignid=MKTAD0930BO1&gl=US&gclid=CLGI3IPY1c4CFYxlNwodPngEAw&gclsrc=ds"
],
[]
] |
|
7n4nn8
|
how is the criterion collection able to restore movies that are 50 plus years old to blu ray quality?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7n4nn8/eli5_how_is_the_criterion_collection_able_to/
|
{
"a_id": [
"drz07pu",
"drz0l00"
],
"score": [
21,
4
],
"text": [
"35mm film still has more detail contained on it than any digital camera can capture. It captures far more texture and nuance, this is why some directors (Tarantino being a popular example) still use \"real\" film. This is comparable to the old records vs. digital format debate in audio recordings. \n\nCelluloid film does have a tendency to break down and degrade over time, but it can be \"remastered\" and digitized, often to considerably better quality than it would have been originally (as seen through an analogue projector). \n\nFor example, I was watching reruns of the original Star Trek run on the BBC yesterday. These episodes never looked better! Not just the remastered \"cgi,\" but every shot was crisper, cleaner, and better colored than I remember them being originally.\n\nEdit: 32-35mm (I was a projectionist for Pete's sake, I should know this!) ",
"Boils down to: \nHow many megapixels does film have? \nInfinitely many! \nIt’s because the image isn’t divided up into tiny squares (the pixels) and is perfectly smooth. \nFilm is far more detailed than digital as it’s analogue so it’s a good source for making better and better versions. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
2gnxl5
|
Has there been any research into the origin of viruses that cause the cold?
|
Did rhinovirus and it's ilk come from an earlier bird virus, or other mammal virus, maybe? Has it been with us longer than domesticated animals? Why have our bodies reacted the same way to these viruses for so long?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2gnxl5/has_there_been_any_research_into_the_origin_of/
|
{
"a_id": [
"ckl641u",
"cklbgf7",
"cklgrgn"
],
"score": [
30,
13,
8
],
"text": [
"Human Rhinoviruses are so different from any other kind of rhinovirus that it gets really difficult to work out which animals we got it from. The truth is, it probably evolved from human enteroviruses that live in the gut, and merely adapted itself to a new niche.\n[Here is an article for you]( _URL_0_)",
"The common cold is a disease classified by its symptoms rather than the specific pathogen which causes it. There are thought to be over 200 different viruses which can cause a cold, so I would have to ask which one you are referring to. However, even if you told me, I wouldn't know the answer to that question. ;-) I am pretty much only going to answer your third question.\n\nCold symptoms are thought to be caused primarily by our immune system's reaction to these viruses rather than direct damage by the virus itself ([discussed here in great detail](_URL_0_)). The reason the symptoms are so similar for such distinct viral infections is essentially because we have a limited number of immune defenses which can be triggered by a wide variety of stimuli and mechanisms. \n\nIn essence, this means that our bodies are not reacting in the same way to THESE SPECIFIC viruses, it's more that this is a common way our bodies respond to infection on a symptomatic level. On a molecular level, however, it's actually quite diverse.",
"Rhinoviruses are indeed thought to come from enteroviruses, as /u/JJBang points out, but have basically forgotten how to survive the high acidity conditions of the stomach, and prefer slightly cooler temperatures. They are part of a family of viruses called the \"picornavirus\" (pronounced pi-COR-nah-virus, which comes from pico RNA virus, because it's small (about 35nm diameter), and contains RNA instead of DNA) which all share several similar characteristics (eg. they all have icosahedral symmetry, they all have a single positive strand of RNA).\n\nThere are several unanswered questions about why we can't get an effective vaccine against rhinoviruses, while we do have vaccines against the closely related poliovirus, which is probably the next best candidate for eradication. One reason seems to be that the surface of the virus is pretty variable between serotypes, and it lacks any large distinguishing features (it's basically a round protein marble, unlike other viruses that have turrets or spikes). Another reason is the lack of error-checking during replication of the RNA genome. There are between 7 and 9 thousand bases in the genome, but because the polymerase has an error rate of about 1 in 10000, during a typical infection, where many many billions of viruses are produced, you'll see every possible mutation. Of course, only the ones that eventually lead to a productive infection will continue to proliferate, so there's selection, but it means that the outside surface of the marble can freely change (provided the receptor binding site remains in tact) so that our immune system can't recognize them.\n\nI don't know enough about where they came from at the dawn of human illness, but we do know they exist in other species. The larger family, picornaviruses, are found in many different types of animals, and even plants."
]
}
|
[] |
[] |
[
[
"http://www.the-scientist.com/?articles.view/articleNo/34189/title/Catching-the-Cold/"
],
[
"http://www.sciencedirect.com/science/article/pii/S147330990570270X"
],
[]
] |
|
1g8exs
|
how can a judge make a decision without letting his own beliefs and opinions interfere with his decision?
|
I'm talking about the more subjective things that are mostly a judgement call.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1g8exs/eli5_how_can_a_judge_make_a_decision_without/
|
{
"a_id": [
"cahr332",
"cai0pc5"
],
"score": [
6,
3
],
"text": [
"A judge is allowed to use the wisdom picked up from her life. There is no bar against it. \n\nA judge is often called on to judge things like credibility--out of the two witnesses with conflicting testimony, which witness does the judge believe more? Usually, at the end of an evidentiary proceeding, the judge will give the reasoning for the decision (I found witness A's testimony more credible than witness B's testimony because . . . \"). As long as the reasoning is not completely arbitrary or based off an improper or prejudicial belief (i.e. men should always get the children in a custody dispute), the decision will typically stand because the judge is in the best position to observe and decide on these things.",
"I've been in front of some shitty judges. One example: Some jerk picked up undocumented day-laborers and worked them to the bone for a month, deliberately paying them in worthless checks. When they found out they were being used for free labor, they demanded pay and the dude threatened to call immigration. This was a crime. Many crimes actually. but the judge found him not guilty because the victims were \"illegals\", and in her stupid little racist mind, it was perfectly okay to use them as slaves. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
9jxrts
|
Why is there an EpiPen (and generic alternatives) shortage?
|
I have read that they are having difficulty manufacturing them, but what difficulties and why?
|
askscience
|
https://www.reddit.com/r/askscience/comments/9jxrts/why_is_there_an_epipen_and_generic_alternatives/
|
{
"a_id": [
"e6vczg4"
],
"score": [
18
],
"text": [
"EpiPens are a medical device. Medical devices don't really have a \"generic\" regulatory option so any company that decides to sell a EpiPen knock-off needs to do all the testing over again except less testing for the drug. \n\nMoreover, some companies decide to file patents around the device component, so you might not be legally able to make copies. This is what happened to all the asthma inhalers since as soon as the law went into effect banning CFCs in medical devices, Teva Medical filed a patent on propellants other than CFC's in inhalers so a $20 inhaler in the 90's is now $200+ for the same drug and same delivery mechanism. \n\n*Edit: It looks like I forgot to respond directly to the OP's question. Being a medical device, you can't just build another manufacturing line and say everything is ok. You have to build the line, re-test the line to see if it still makes everything correctly at the extreme tolerances (process validations), and make sure your raw material suppliers don't change their materials on their side and still meet your increased capacity. What usually ends up happening in my industry (medical devices) on shortages are usually due to: (1) One of the key raw material suppliers cannot make enough of a component, (2) Your new or existing line fails process validations/in-process checks, (3) FDA/notified body audit findings triggering shutting down the line, or (4) A massive product recall that is currently in-progress.\n\nWith (3), I've seen the FDA at times try to negotiate with companies not trying to shut down a key product-line, but companies usually end up shutting the line down out of spite and have the physicians & patients file complaints to the FDA. I am personally unsure of which of the reasons are causing EpiPens to be in short supply, but I wouldn't be surprised if it is one of the above causes. "
]
}
|
[] |
[] |
[
[]
] |
|
5f8lp1
|
why do we sometimes, out of the blue, have the urge to breath deeply?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5f8lp1/eli5_why_do_we_sometimes_out_of_the_blue_have_the/
|
{
"a_id": [
"daibm99",
"dairbxl"
],
"score": [
7,
2
],
"text": [
"When at long periods of rest your body can start to breath less and less l. After a time your brain goes fuck I need air and tells your lungs to reset themselve l. This can also be the cause of yawning sometimes (not the only cause thow)",
"I believe it's something akin to \"stretching\" your diaphragm, much like you occasionally have the urge to strech random muscles."
]
}
|
[] |
[] |
[
[],
[]
] |
|
1f1alj
|
How did American politics move so far to the right?
|
It seems like the USA's politics has a huge vacuum where left-leaning parties should be, how did it become a battle between one right wing party and one slightly more right wing party?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1f1alj/how_did_american_politics_move_so_far_to_the_right/
|
{
"a_id": [
"ca5xt3b",
"ca5zf4h"
],
"score": [
4,
6
],
"text": [
"Depending on how you define left/right American politics really aren't that far right. In America the far right is usually classified as being small government. Reagan's quote, \"Government isn't the solution to the problem. Government **IS** the problem.\" encapsulates this well. If that is an accepted definition the far right isn't fascism as many people claim, splitting the left and right extremes as Communism and Fascism. The far right would be the exact opposite of these, Anarchism, which is the complete lack of a state or government.\n\nThe Democratic Party and Republican Party are in fact both left wing parties. They both support government re-distribution of wealth through taxation and welfare, the central control of the economy through money control and centralized banking, and the growth of the power of the central government. They both also support expanding international wars to justify much of their control assumption. To someone on the actual far right both of these parties fit very well on the American Left political spectrum. ",
"I would say that a lot of it comes down to the First Red Scare. In the early 20th century, the Industrial Workers of the World (an anarcho-syndicalist revolutionary labor union) was growing large and the Socialist Party of Eugene Debs was getting around 7% in U.S. elections, with hundreds of mayors, state representatives, and a few congressmen. During the First Red Scare, during and following World War I, the IWW was repressed, and socialist and anarchist leaders like Eugene Debs and Ricardo Flores Magón (a Mexican anarchist revolutionary and IWW member who had been in exile in the U.S.) were imprisoned, where many would die. Thousands of striking workers would be repressed, with public justifications citing socialism, communism, and anarchism.\n\nI know less about the Second Red Scare in the 1950s, but it's my understanding that there were a number of socialists and communists in the leadership of the CIO (Congress of Industrial Organizations) that were purged."
]
}
|
[] |
[] |
[
[],
[]
] |
|
7wb8u7
|
How exactly does fluticasone nasal spray work?
|
The stuff immediately makes my allergy symptoms go away. I know it’s a corticosteroid but I can’t find an actual breakdown of what it’s doing once inhaled.
|
askscience
|
https://www.reddit.com/r/askscience/comments/7wb8u7/how_exactly_does_fluticasone_nasal_spray_work/
|
{
"a_id": [
"dtz0ufi"
],
"score": [
3
],
"text": [
"[From the package insert:](_URL_0_)\n\nFluticasone propionate is a synthetic trifluorinated corticosteroid with anti-inflammatory activity. Fluticasone propionate has been shown in vitro to exhibit a binding affinity for the human glucocorticoid receptor that is 18 times that of dexamethasone, almost twice that of beclomethasone-17- monopropionate (BMP), the active metabolite of beclomethasone dipropionate, and over 3 times that of budesonide. Data from the McKenzie vasoconstrictor assay in man are consistent with these results. The clinical significance of these findings is unknown.\n\nThe precise mechanism through which fluticasone propionate affects rhinitis symptoms is not known. Corticosteroids have been shown to have a wide range of effects on multiple cell types (e.g., mast cells, eosinophils, neutrophils, macrophages, lymphocytes) and mediators (e.g., histamine, eicosanoids, leukotrienes, cytokines) involved in inflammation. In 7 trials in adults, Fluticasone Propionate Nasal Spray has decreased nasal mucosal eosinophils in 66% of patients (35% for placebo) and basophils in 39% of patients (28% for placebo). The direct relationship of these findings to long-term symptom relief is not known.\n\n\n"
]
}
|
[] |
[] |
[
[
"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=7c692ed5-959e-4c48-aeec-0799d8979693"
]
] |
|
14ewe6
|
If a human had to live on only one food (eating as much as necessary, but all the same thing), what would the best to live off? (Assume otherwise healthy adult).
|
askscience
|
http://www.reddit.com/r/askscience/comments/14ewe6/if_a_human_had_to_live_on_only_one_food_eating_as/
|
{
"a_id": [
"c7cg23t",
"c7cgim4"
],
"score": [
3,
2
],
"text": [
"I may be mistaken, but I read an article that said a human could live off baked potatoes and butter indefinitely as it provides all the necessary nutrients",
"There are several existing threads about this."
]
}
|
[] |
[] |
[
[],
[]
] |
||
94f7me
|
WW2 buffs, were there any instances of any bombers doing gunships runs like a AC-130 would?
|
I'm just curious really, maybe something near the end of the war, when the Luftwaffe was pretty much not a threat anymore? Thanks!
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/94f7me/ww2_buffs_were_there_any_instances_of_any_bombers/
|
{
"a_id": [
"e3lkicx"
],
"score": [
6
],
"text": [
"The short answer to this is \"No\". There wasn't a comparable weapon - an aircraft designed for heavy, air-to-ground fire over long durations - to the AC-130 gunship during World War II. The AC-130's predecessor, the AC-47 \"Spooky\", or more popularly, \"Puff the Magic Dragon\", while using the C-47 as its platform - an aircraft available in WWII - was a product of the 1960s. *Now*, that said, the AC-47 was not born out of thin air, and does exist in a long line of ideas and prototypes that were in existence during World War II, and even before.\n\nWhile putting a bunch of machine guns in a plane for strafing predated WWII - way back in the '20s the US Army's first designated 'Attack\" aircraft, the A-2, carried 2 .30 cals and 4 more in the wings - bigger guns started rolling out during the conflict. The brainchild of Maj. Paul I. “Pappy” Gunn, testing of heavily armed B-25s with 8 .50 cals replacing in the nose, principally in the Pacific against Japanese shipping, proved to be quite successful. Further testing with even bigger guns resulted several interesting variants which were designed to bring massive amounts of firepower to bear during their strafing runs. The B-25G and B-25H included a number of .50 cal machine guns and a massive 75mm cannon which could tear into just about anything - mainly envisioned for ships, tanks, and fortifications - while the B-25J ditched the cannon to just rely on the firepower of the machine guns. With 8 in the nose, 4 'blisters' on the side, and the top turret facing forward with 2 more, even without a cannon, 14 .50s were nothing to laugh at, being the most 'forward firepower' of any Allied attack plane . The 'gunship' models still carried a conventional bomb-load of several thousand pounds for additional 'umph' (lacking the cannon, the 'J' could of course carry more than the 'G' and 'H'). Some would also see service with the Marines, designated the PBJ-1H. \n\nSimilarly, the A-26B was built to mount 6, 8, or even 10 .50 cals in the nose depending on the sub-model, and later modifications, some which only saw action in Vietnam, also allowed 8 rockets or 6 more .30 cals on the wing, or replacement of the .50s with 4 20mm cannons. A purpose built platform for the 75mm (and early drafts actually envisioned it as a bomber killer, not an attack aircraft), the XA-38 Grizzly, was also built mounting a 75mm cannon and 6 .50 cals. The first model rolled out in May, 1944, and performed well, but far too late for the war. The second prototype was built, but the war was already seen as nearing an end, and further, as it shared an engine with the B-29 which had priority, production was never ordered.\n\nWith that many guns though, in all cases the emphasis was on only a few overwhelming strafing runs. In the case of the cannon, the obvious slow rate of fire required a fairly stressful low, slow, and steady approach to line up a shot. As for the massive banks of machine guns, well, ammunition ain't light, and even with 400+ rounds per gun, it meant only a few seconds of actual firing. Depending on the mission too, guns might be stripped to allow more bomb load, which further illustrates that these were still, in the end, not quite the gunship you have in mind.\n\nTo be sure, all of these configurations were based on the idea that the planes would be performing CAS duties or shipping interdiction, coming in low for strafing runs of the target, not circling far up in the sky keeping fire pinpointed, but they do fit into the broader idea of gunship support. The US Army had toyed with the idea in the interwar years, even running a successful test in 1926 by 1LT Fred Nelson of side-firing machine guns on a DH-4, but nothing ever came out of that during peacetime. During the war, it wasn't really revisited, as there was really just one guy who was beating the drum for this, 1LT G.C. MacDonald, and he was mostly ignored. He submitted a proposal in 1942 for side-firing machine guns, and in 1945, upped the ante with a proposal for bazookas mounted on spotter planes, but was ignored. 'On the ground' modifications did result in a handful of C-47s being fitted with waist-mounted .50 cals to provide support in Burma but this was an entirely off-the limited addition that was not imitated elsewhere, nor even particularly known about.\n\nAs a Lt. Col. in 1961, MacDonald would again submit his proposal to a Tactical Air Command panel looking at solutions for defending the 'Strategic Hamlets' in Vietnam, but was ignored again. It was only a chance meeting that MacDonald had later that year with Ralph Flexman, an engineer with Bell doing active reserve duty who had also been pondering a similar idea, that would see the project gain wings, eventually resulting in the AC-47.\n\n**Further Reading**\n\n Development and Employment of Fixed-Wing Gunships 1962-1972 by Jack S. Ballard\n American Attack Aircraft since 1926 by E.R. Johnson.\n Beech Aircraft and their Predecessors by AJ Pelletier\n Gunships: A Pictorial History of Spooky by Larry Davis\n B-25 Mitchell Units of the MTO by Steve Pace\n A-26 Invader Units of World War II by Jim Roeder\n The Illustrated Encyclopedia of Combat Air by Bill Gunston\n PBJ Mitchell Units of the Pacific War by Jerry Scutts\n\nEdit: Oh! I almost forgot one other thing to mention. Obviously, this is just the US. I'm familiar with several of the CAS aircraft they used in this mold, so that is what I focused on. *But* there is the Soviet Tupolev Tu-2Sh. I can't say much about it as, well, I don't have too much on it, but it is touched on briefly in \"Twin-Engined Fighters Attack Aircraft and Bombers\" by Yefiim Gordon and Tupolev Aircraft Since 1922 by Bill Gunston, which I'm drawing on here.\n\nBasically, the Soviets made several test versions of this, but never went into production with any of them. One was not unlike the American planes above. A big 75mm gun in the nose for taking down big targets. A similar version, tried post-war, went a bit more varied with two 45mm cannons, two 37mm cannons, and the usual two 20mm cannons on the wings, plus a 12.7mm turret on top. A version with a 57mm cannon mounted from the bomb bay and the two 20mms also was tested. However, these were all, well, the *practical* tests. The original test was quite the monster, with 88 PPSh-41 submachine guns crammed into the fuselage, angled downwards to fire at infantry as it flew above them. Technically it worked but reloading in the air was such a problem that they didn't continue with the project. Even with the big 72-round drum magazine, it was just too short a firing window to be worth bothering, I guess, and they instead went with the more conventional tests above. Still though, it is possibly the closest thing to the Spooky or AC-130 built in World War II."
]
}
|
[] |
[] |
[
[]
] |
|
21dur8
|
When (or how) does a religion become mythology?
|
In high school I remember doing a small unit in my English class on Norse mythology and I'm just wondering how it went from being a religion to mythology. I hope this isn't a dumb question, I know extrodinaraly little on the subject. Thanks!!
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/21dur8/when_or_how_does_a_religion_become_mythology/
|
{
"a_id": [
"cgc805q"
],
"score": [
7
],
"text": [
"Technically speaking, every religion have mythology (a set of myths and stories), but in common use, the word *mythology* is typically used for the myths of religions which have no more active followers. So in short, Norse religion became mythology when the Norse became Christianized.\n\nA living religion consists of much more that the myths and stories - it may have traditions, rituals, festivals, institutions, perhaps some kind of priesthood. But when a religion dies out, the rituals and institutions cease to exist. What remains is the mythology, at least if it was written down and preserved. "
]
}
|
[] |
[] |
[
[]
] |
|
3qyblt
|
what would have happened in china if you got pregnant with a second child?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3qyblt/eli5_what_would_have_happened_in_china_if_you_got/
|
{
"a_id": [
"cwjcihm",
"cwjcjgr",
"cwjdo9g",
"cwjfrwa"
],
"score": [
6,
9,
2,
2
],
"text": [
"The one child policy wasn't as rigidly enforced as people may think.\n\nI don't know the exact number, but I think the average family size in China since the policy started is something like 1.5 children.",
"You would pay a one time fine at the birth of your child (or when it was discovered) and you would pay extra taxes. ",
"As others have noted, you had to pay a large but typically not impossible fine.\n\nThe large number of Chinese adoptees were more often first children who turned out to be girls. Under China's traditional culture, boys are expected to sustain their parents in old age, while girls marry and become part of the new family. Because China doesn't have much retirement security, it was very important to have a boy, and if you could on,y have one child, it became a matter of economic necessity.",
"It depends on where you lived and what your status was.\n\nLiving in rural areas, the enforcement was lax. But it ranged from forced abortions and sterilizations to paying fines (to corrupt officials). \n\nLiving in urban areas, the social enforcement with peer pressure was more than legal enforcement. Enforcement ranged from fines to limitations warnings. Well connected folks, like my parents, would get thru back channels to have a second child like myself. I only know of one other family growing up with 2 kids."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
1x3l6e
|
Did professional assassins exist in medieval Europe? If so, where would they be trained? How would one become an assassin?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1x3l6e/did_professional_assassins_exist_in_medieval/
|
{
"a_id": [
"cf7uw0f",
"cf7wee3",
"cf7z3kb",
"cf7zwwe"
],
"score": [
70,
453,
743,
4
],
"text": [
"If I may ask a question in this thread relevant to the main question -\n\nDid any of the holy orders have people trained to fulfill the roles of assassins/spys during the medieval period?\n",
"I think I can probably answer the question by answering a slightly different question. It hedges on vioating the 20 year rule, but this is really just illustrative. \n\nSuppose you were to ask the question, \"Do professional assassins exist in the present day?\" \n\nThe answer to this question depends on how you mean \"assassin.\" In the terms that you seem to be asking, the answer is almost certainly no. There are certainly soldiers trained to a high level of skill etc. and while I have little doubt there are some people who kill for criminal organizations, these are by and large people that do not keep records of the sort that a historian might ever find, except for those that get caught. A group of \"professional assassins\" that is known could not openly survive for long. Criminal \"assassins\" are usually far closer to thugs than \"professionals\" in any case. Usually it's find an excuse to get close, then open up with a pistol, going down in the process. \n\nRather, what you find is that when \"assassinations\" happen in the modern world, it's usually a lone gunman or bomber who is not particularly \"professional,\" and dies in the attempt. Sometimes it's a whole team of operatives, but then they're distinctly military or paramilitary rather than some covert group. (see. e.g. Benazir Bhutto's assassination). \n\nEven though the historical context changes dramatically, I think you can compare modern times to historical times in this regard. Most assassinations in the historical record were not performed by someone you would describe as a \"professional.\" \n\nFor proof, take a look at [european assassinations](_URL_4_) \n\n[Louis, Duke of Orleans 1407 ](_URL_5_) - subterfuge lures the duke out into the open where 15 masked thugs stab and beat him. \n\n[Henry III, King of France, 1575](_URL_0_) - A domnican friar, Jaque Clement, gains admittance to the king's presence with documents, saying he has a message for the king. He stabs the king once and is killed on the spot by the guards. the king later dies of the wound. \n\n[Henry IV, King of France, 1610](_URL_1_) A catholic fanatic Francois Revellec waits until the king's carriage is stopped by a traffic blockage (possibly arranged by compatriots) climbs into the carriage and stabs the king. He is immidiately arrested, tried and executed. \n\n[Phillip v Hohenstauffen \"King of the Germans\" and Prince of Swabia 1208 - ](_URL_6_) - the king granted an audience to another noble, Otto VIII v. Wittlesbach, who drew his sword and stabbed the king in the neck. (Apparently over a dispute caused by a broken wedding engagement). Wittlesbach fled and then was tracked down and killed. \n\n[Guliano de'Medici, Duke of Florence, 1478](_URL_2_) was killed in the \"pazzi conspiracy\" - a plot to remove the Medici family as the rulers of Milan, Bernardo Bandi and Francesco de' Pazzi, themselves italian nobility, wait until Guliano d'Medici is attending church, attack him and stab him 19 times. \n\n\n[William I of Orange, 1584](_URL_3_) - After William gained independance for the Netherlands, Philllip II of spain declared him an outlaw and promised a bounty of 25,000 Crowns. Balthasar Gerard, a catholic frenchman, made an appointment with William, gained an audience, shot William in the chest at close range with a wheel lock pistol, then fled. \n\n\nWhile that's not exhaustive, I think that gives a pretty good selection of medieval era assassinations. By and large they're not all that different than you might expect an assassination to be today. It's far more likely to be some crazy with a knife or a gun, dying in the attempt, than some highly trained operative who kills and vanishes. \n\nEdit: fixed various spelling and grammatical errors. Thanks to /u/Sparadise for the correction. ",
"In the sense of the blade-wielding master of espionage who could plow through a dozen guard single-handedly? No. That, unfortunately, is something that only exists in the realm of legends and [entertainment media](_URL_7_).\n\nThe word \"assassin,\" as you might already know, entered into many European languages via the Crusades as a bastardization of the Arabic حشاشين (_hashishiyyin_), referring to a sect of Nizari Isma’ilis in present-day northern Iran who orchestrated a series of political assassinations in the 1100s. The name is supposed to be a derogatory term meaning “hashish-consumers,” deriving from the belief that Nizari _fida’is_ (devotees) were worked into a frenzy through the consumption of the drug. However, most scholars recognize that there is no proof of this. The story comes from Marco Polo’s writings, specifically a section entitled “Concerning the Old Man of the Mountain” (Book 1, Chapter 23), where he claimed he heard from some natives that an old man in Mulehet drugged his followers and secluded them in a garden to trick them into believing they could enter Paradise:\n\n > He kept at his Court a number of the youths of the country, from 12 to 20 years of age, such as had a taste for soldiering, and to these he used to tell tales about Paradise, just as Mahommet had been wont to do, and they believed in him just as the Saracens believe in Mahommet. Then he would introduce them into his garden, some four, or six, or ten at a time, having first made them drink a certain potion which cast them into a deep sleep, and then causing them to be lifted and carried in. So when they awoke, they found themselves in the Garden.\n\nThere haven’t been any other sources to substantiate this. Historians even disagree on the etymology of the word _hashishiyyin_. [Farhad Daftary](_URL_4_), for example, claims that the word, though used pejoratively, had no true connection to the drug hashish. It was simply a derogatory word used by Nizaris for other Muslims that the Crusaders picked up in the Levant, and the assassin myths sprang up along with a number of rumors regarding secret practices of the Nizari Isma’ilis (10-11). The word picked up the connotation of professional killer around the mid-14th century. Dante, for example, spoke of \"_Le perfido assassin_\" in the _Inferno_. “Assassin” up to that point was exclusively associated with Muslims, and even after it was often [used in the plural](_URL_13_) by Orientalists.\n\n**So to return to the original question** - whether there were types of trained killers, mythic or otherwise, in the medieval European context - it doesn’t seem likely. The most effective assassins are those who can get close to their targets without arousing suspicion and kill him/her with as little risk to themselves as possible. In other words, you didn’t need to be trained as sword-wielding acrobat with a devil-may-care attitude to be an effective assassin. \n\nInstead of death by cold steel, **the most common method of assassination in medieval Europe by far was poisoning**. Poisons were cheap and relatively easy to obtain, and poisoning is a clever way to conceal assassination as an illness (most poisons wouldn’t cause you to drop dead on the spot - at least not if the perpetrator was doing it right). There were many herbal poisons readily available (e.g. [Nightshade](_URL_5_), [Water Hemlock](_URL_0_), [Laburnum](_URL_9_), or [Black Hellbore](_URL_1_)), but there were also more deadly chemicals such as [arsenic powder](_URL_14_). Deliberate poisoning of food was common enough in Europe that it was often widely believed to be the cause of many royal deaths, whether or not it was true. When King John of England died in 1216 of dysentery, for example, numerous rumors began almost immediately that he had been poisoned by a monk. There were many visual images of this poisoning that circulated for years to come, both in [prints](_URL_6_) and in [illuminated](_URL_11_) [manuscripts](_URL_10_). There were so many rumors about Lucrezia Borgia and her brother Cesare poisoning their enemies that they were said to own [rings with secret compartments](_URL_12_) used to casually slip poison unnoticed into glasses. There isn’t much evidence to link them directly to this, but it shows the extent to which the idea of assassination was linked to poison. And yes, some affluent individuals [did employ food-testers](_URL_8_) as a deterrent against this kind of risk.\n\nAnyone who had extensive knowledge of poisons, then, might be considered a potential assassin (or at least able to aid a potential one). With the printing press, pharmacology manuals detailing poisons became more widely available; Magister Santes de Ardoynis’s _The Book of Venoms_ (1424) was probably the most popular. However, before then most major cities contained apothecary guilds comprising a large number of tradesmen knowledgeable in poisons. Apothecaries, of course, were not simply poison-sellers, but rather served as both pharmacist and general medical practitioner in the Middle Ages. In many ways, [apothecaries were a vital resource](_URL_2_) for medicine in medieval Europe. So this raises a question: why did apothecaries sell poisons at all? Well, in their view they didn’t. It was a long-standing belief in many parts of Europe that certain plant extracts which were poisonous in large doses were beneficial to one’s health in smaller doses. For example, Henbane - the poison Claudius uses to murder the former king in Shakespeare’s [_Hamlet_](_URL_3_) - was sometimes recommended in small doses as a sleeping agent or as a sedative for hysteria. The same items could be used as a form of pest control. Mix Aconite with animal fat and/or honey and you have an effective way to kill a wolf or a fox threatening your livestock.\n\nAll of these concoctions, then, had designated uses other than murdering human beings and were sold as medical remedies. But they could be used to commit murder in large doses. The trick was knowing what the right dose was to induce death without making it obvious that the victim had been poisoned.\n\n**EDIT**: fixed a broken link and a typo.\n\n",
"I have a follow-up question of sorts: I know a little (very little; dangerously little) about ninja in medieval Japan and their counterparts in China -- they were basically groups for hire, \"muscle\" if you will, but trained for the job. That's as far as my knowledge goes, and it could be totally wrong. \n\nThe question (other than hoping for any clarification on the above), is, were there any comparable groups in medieval Europe? Mercenary groups that trained independently of militaries for the purpose of hiring services out. I'm hoping this question makes any sense at all. "
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Henry_III_of_France#Assassination",
"http://en.wikipedia.org/wiki/Henry_IV_of_France#Assassination",
"http://en.wikipedia.org/wiki/Giuliano_di_Piero_de%27_Medici",
"http://en.wikipedia.org/wiki/William_I_of_Orange",
"http://en.wikipedia.org/wiki/List_of_assassinations",
"http://en.wikipedia.org/wiki/Assassination_of_Louis_I,_Duke_of_Orl%C3%A9ans",
"http://en.wikipedia.org/wiki/Philipp_von_Hohenstaufen"
],
[
"http://www.botanical.com/botanical/mgmh/d/drophe21.html",
"http://www.botanical.com/botanical/mgmh/h/helbla14.html",
"http://books.google.com/books?id=K3fv-0iophEC&printsec=frontcover&dq=mary+lindemann+medicine&hl=en&sa=X&ei=7qjyUpKxGqasyAHtuYHIAg&ved=0CDQQ6AEwAA#v=onepage&q=mary%20lindemann%20medicine&f=false",
"http://books.google.com/books?id=kjQJAAAAQAAJ&pg=PA245&dq=shakespeare+henbane&hl=en&sa=X&ei=NKLyUoSCOZKCyAGF64GABQ&ved=0CDYQ6AEwAg#v=onepage&q=shakespeare%20henbane&f=false",
"http://books.google.com/books?id=cSO9zh61AGEC&dq=The+Ismailis:+Their+history+and+doctrines&source=gbs_navlinks_s",
"http://www.botanical.com/botanical/mgmh/n/nighde05.html",
"http://kb.osu.edu/dspace/bitstream/handle/1811/25024/P00004.jpeg?sequence=1",
"http://blogs-images.forbes.com/carolpinchefsky/files/2012/10/AssassinsCreed.jpg",
"http://www.reddit.com/r/AskHistorians/comments/1u7gwr/are_there_many_cases_of_a_food_taster_actually/",
"http://www.botanical.com/botanical/mgmh/l/labrun02.html",
"http://streetsofsalem.files.wordpress.com/2013/08/poison-cup-socrates.jpg?w=490&h=606",
"http://www.sciencephoto.com/image/548136/530wm/C0179189-King_John_is_offered_poison-SPL.jpg",
"http://www.eclecticvintage.com/pics/r50402.florturqring2.jpg",
"http://books.google.com/books?id=q1sOAAAAQAAJ&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false",
"http://books.google.com/books?id=L6Ahq0FuVK8C&printsec=frontcover&dq=The+Arsenic+Century&hl=en&sa=X&ei=-5zyUt37E83YyAHclIGQDg&ved=0CDoQ6AEwAQ#v=onepage&q=The%20Arsenic%20Century&f=false"
],
[]
] |
||
4mgw1b
|
why is saying hello to people socially so important ?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4mgw1b/eli5_why_is_saying_hello_to_people_socially_so/
|
{
"a_id": [
"d3vkjn5"
],
"score": [
2
],
"text": [
"It isn't. But it's the most socially neutral equivalent of a greeting. Greetings or acknowledgement at first meets are important. If you don't acknowledge someone you are sending pretty much the opposite signal of a greeting, and depending on the person that can be a can of worms. There are tons other ways to greet someone through body language only (and more fancy ways through words), but what to use depends on your relationship to said person and social context. If you do not know which choice is appropriate saying \"Hello\" is your best option, and better than doing nothing. And that is why just saying hello is a good suggestion for everyone. "
]
}
|
[] |
[] |
[
[]
] |
||
14fomq
|
What percentage of the worlds land mass is used for the production of food?
|
.
|
askscience
|
http://www.reddit.com/r/askscience/comments/14fomq/what_percentage_of_the_worlds_land_mass_is_used/
|
{
"a_id": [
"c7cy6je"
],
"score": [
2
],
"text": [
"153,335,392,000 Hectares are used for food (arable & permanent crops)\n\n1,300,346,805,000 Is the total land surface\n\nThats 11.79188439%\n\nSource: [FAOSTAT](_URL_0_)"
]
}
|
[] |
[] |
[
[
"http://faostat.fao.org/"
]
] |
|
dhb9b9
|
What are the most concerning potential shortages in natural resources?
|
[Helium](_URL_1_)? [Lithium](_URL_0_)? [Sand](_URL_2_)? Is it possible to rank them by concern?
|
askscience
|
https://www.reddit.com/r/askscience/comments/dhb9b9/what_are_the_most_concerning_potential_shortages/
|
{
"a_id": [
"f3pao1g"
],
"score": [
5
],
"text": [
" > Helium? Lithium? Sand?\n\nNone of those are required for our survival. Compare this to the [loss of insect biomass](_URL_0_) or a [shortage of farmland](_URL_0_) due to climate change. Either of those things would mean that humanity will eventually run out of *food*. That means mass starvation and wars for whatever usable land remains."
]
}
|
[] |
[
"https://www.allaboutcircuits.com/news/looming-shortage-lithium-cobalt-electric-cars-politics-battery-chemistry/",
"https://www.nytimes.com/2019/05/16/science/helium-shortage-party-city.html",
"https://www.businessinsider.com/global-sand-shortage-could-cause-damaging-effects-2018-12?IR=T"
] |
[
[
"https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0185809"
]
] |
|
2lr1nm
|
how does the binary options scam work?
|
Can you really make money of it? Or is it just a clever scam as i suspect?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2lr1nm/eli5how_does_the_binary_options_scam_work/
|
{
"a_id": [
"clxdcj7"
],
"score": [
3
],
"text": [
"After sifting through a few pages, it's just gambling, plain and simple."
]
}
|
[] |
[] |
[
[]
] |
|
a5h2dz
|
Need help with advanced ceramics(?)
|
askscience
|
https://www.reddit.com/r/askscience/comments/a5h2dz/need_help_with_advanced_ceramics/
|
{
"a_id": [
"ebmgt44",
"ebmhqk8"
],
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3,
2
],
"text": [
"Manufacturing methods are pretty broad, depending on material. Many are made in similar, but more carefully controlled, ways to pottery: a slurry that is formed or cast, etc., and then fired, often under even higher temp and possibly under controlled atmosphere.\n\nA more unique route, which is also worth looking into, would be for instance \"precursor-derived ceramics\" or \"polymer-derived ceramics\". Basically using small silicone-based molecules (silanes, siloxanes, etc. or polymers of them) that are sintered to produce ceramics.\n\nAs far as applications for advanced ceramics, there are many. High temperature refractories, corrosion resistant or heat resistant coatings... Those are for instance important for some types of power plants, including nuclear plants. Also used for aircraft sometimes as coatings for engine parts that see high temp, or famously on the underside of the space shuttle got heat abatement on reentry.\n\nThere are also low-friction ceramic parts, for instance in high-end bearings and moving parts like bicycle wheels.\n\nThere are also electronic applications of ceramics, such as piezoelectric systems, or ceramic superconductors (no longer as relevant as once was hoped, as they need to be super-cooled to conduct, though).\n\nOptical applications exist as well, with a big focus these days on conductive transparent materials like indium tin oxide.\n\nThere's even more, but I hope this gives you a good start, good luck with your work! ",
"Thank you for your submission! Unfortunately, your submission has been removed for the following reason(s):\n\n* /r/AskScience is not the correct forum for users to look for help on their homework, craft or personal projects, research projects, essays, etc. A more suitable subreddit would be /r/HomeworkHelp. Please see our [guidelines.](_URL_0_.) Depending on the exact subject, there may be more suitable subreddits like /r/AskMath, /r/AskPhysics, /r/PhysicsHelp, or /r/chemhelp.\n\n\n\nIf you disagree with this decision, please send a [message to the moderators.](_URL_1_)"
]
}
|
[] |
[] |
[
[],
[
"http://www.reddit.com/r/askscience/wiki/guidelines#wiki_as_is_not_here_to_do_your_homework_for_you",
"https://www.reddit.com/message/compose?to=%2Fr%2Faskscience"
]
] |
||
2e0jod
|
Were there many historically significant battlefields in WWI and WWII?
|
I read about a battle of Borodino in WWII, even though it obviously wasn't as significant as its more famous cousin and you can barely find it if you Google it I thought that was pretty cool. Were there many battles that took place on previous famous battlegrounds, something like a second battle of Waterloo, but this time with tanks.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2e0jod/were_there_many_historically_significant/
|
{
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"cjv13gc",
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"text": [
"There was quite a sizeable battle in Verdun in 1792. \nA better example might be Metz where there was a big battle in both the Franco Prussian war and the second world war. \nBesides that, it wouldn't be too hard to find battlefields in Belgium or northern France whereseveral battles could have taken places. ",
"The Ardennes forest in France saw substantial battles in both world wars. \n\n[WWI](_URL_2_)\n\n[WWII](_URL_0_)\n\nAs did the city of [Amiens](_URL_1_)\n\n\n",
"Perhaps the battle of Thermopylae in April 1941 would be of interest, when the ANZACs tried to hold the pass against the German forces. There were five Australian and three New Zealand battalions involved. The ANZAC forces took up their position on 15 April, but the battle didn't begin in earnest until the 21st. The Germans had complete air superiority, and could easily have used artillery on Euboia to blow the defenders to shreds. But late on the same day, the Allied forces decided to withdraw from Greece altogether, so the battle was short-lived. The ANZACs were evacuated by the end of the 24th."
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Battle_of_the_Bulge",
"http://en.wikipedia.org/wiki/Amiens#The_First_World_War",
"http://en.wikipedia.org/wiki/Battle_of_the_Ardennes"
],
[]
] |
|
p1igy
|
There are obvious reasons behind human beauty (fertility, child raising) but why do we perceive non-human things (natural vistas, cute animals) as beautiful?
|
askscience
|
http://www.reddit.com/r/askscience/comments/p1igy/there_are_obvious_reasons_behind_human_beauty/
|
{
"a_id": [
"c3lqr7a",
"c3lqxoc"
],
"score": [
2,
2
],
"text": [
"_URL_0_\n\nDespite not being human, \"cute\" things still display neoteny, which as mammals we have a vested evolutionary interest in, given the importance we place on raising offspring. \n\nOne could \"layman speculate\" that this is exacerbated in humans, which care for their young much longer than other mammals, and human infants are relatively much more helpless and dependent during infancy.\n\nThe wikipedia article has research with corroborates all of that.\n\nAs someone with a degree in the humanities, I can \"non-layman speculate\" that a breathtaking vista in the Alps would be much less breathtaking if you were fighting for your survival in the harsh environment of the Alps for any extended period.\n\nThe urban alleyway is \"trashy\" and \"run down\" because it has elements which you associate with the negative connotations of \"trashy\" and \"run down.\"\n\nA better way to say this is that a large degree of our aesthetics are culturally conditioned, both in our language, and our ideology. An alleyway is \"common\" \"dirty\" and not of value. These are not things we associate with beauty. Thus, the alleyway is not beautiful.\nBut this is boarder-line linguistics and social psychology now, running into the territory of philosophy (yuck). ",
"There's a brilliant [Ted Talk](_URL_0_) on this."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Cute"
],
[
"http://www.ted.com/talks/lang/en/denis_dutton_a_darwinian_theory_of_beauty.html"
]
] |
||
5fzl6g
|
What was the Jazz scene in 1920s/30s Shanghai like?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5fzl6g/what_was_the_jazz_scene_in_1920s30s_shanghai_like/
|
{
"a_id": [
"darhxm6"
],
"score": [
3
],
"text": [
"Jazz at this time was *the* thing to do for nightlife, and Shanghai was the centre of jazz in China.\n\nJazz was introduced to the city through the foreign concessions in the 19-teens. The International Settlement and the French Concession both regularly had jazz musicians, often coming from the United States. The interest in jazz spread to the Chinese population shortly after. It survived well into the 1940s there. It stopped primarily as a result of being banned by the Communists around 1949.\n\nPrior to that, big bands and jazz orchestras were quite common at the jazz cabarets throughout the foreign concessions. The reception among members of Chinese society was also generally positive toward the style. Shanghai in the 1920s was a place you went to experience something new, usually directly a result from the mix of cultures to be found there. Modernising and urbanising means adopting the latest trends, and Shanghai at this time was right in line with the trends found in bigger cities in the West.\n\nThese were also some of the few places that foreign residents of the concessions and native Chinese could actually co-mingle. They not only offered an outlet for the residents of the city, but were also a profitable front for the various gangs that managed much of the city at the time. One of the larger gangs, the [Green Gang](_URL_1_), even put together the first jazz band made entirely of Chinese musicians in 1934. Called the Breeze Dance Band, also translated as Clear Wind Jazz Band (清风舞乐队), it was originally pushed for by [Dù Yuèshēng 杜月笙](_URL_2_), one of the most prominent mobsters of the period, and led by [Lí Jǐnhuī 黎錦暉](_URL_0_). Lí became a hugely important person in 20th century Chinese music, and was an active proponent of the modern development of Chinese culture.\n\nAdditionally as part of the cabarets, gambling and prostitution adapted to the cabarets and it was not uncommon to find \"dance hostesses\", women who, for a price, would dance and drink with clients for the night. This obviously also resulted in prostitution, but not always.\n\nEven government officials were in on the craze, and Chiang Kai Shek himself had a jazz orchestra playing at his wedding to Soong May-ling.\n\nYou can actually find a lot of archival footage of [jazz clubs](_URL_3_) if you dig around a bit. \n\nIf you're interested in the topic I highly recommend Andrew Field's work, below.\n\n**References**\n\n* Andrew Field's *Shanghai's Dancing World: Cabaret Culture and Urban Politics, 1919-1954*\n\n* James Farrer & Andrew Field. *Shanghai Nightscapes: A Nocturnal Biography of a Global City*\n\n**See also**\n\n* This [audio interview](_URL_4_) with Andrew Field where he talks about some of the above/\n\n---\n\nSomeone asked a similar question some months back. This answer is based largely on my answer from then.\n\nalso cc /u/origamitiger, because RemindMe won't work in /r/AskHistorians"
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/Li_Jinhui",
"https://en.wikipedia.org/wiki/Green_Gang",
"https://zh.wikipedia.org/wiki/%E6%9D%9C%E6%9C%88%E7%AC%99",
"https://www.youtube.com/watch?v=k3rbLyeYiJU",
"http://newbooksnetwork.com/andrew-field-shanghais-dancing-world-cabaret-culture-and-urban-politics-1919-1954-the-chinese-university-press-2010/"
]
] |
||
3m87fq
|
why do rock bands often have a carpet on the stage?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3m87fq/eli5why_do_rock_bands_often_have_a_carpet_on_the/
|
{
"a_id": [
"cvctb0c",
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"score": [
2,
2
],
"text": [
"Stages are very hard. The rugs provide a softer surface to stand on. There is usually an additional layer of padding under the rug as well. ",
"Drummers do it to keep their drums from 'walking' away. Even though all your hardware have little rubber feet on them, if you're banging on the drums hard enough and they're on a smooth surface, they'll start to spread out. Keith Moon from the Who actually had to tie his down to keep them in place.\n\nFor guitarists, bassists, singers, etc, it's more of a comfort thing as far as I know. It's way easier on your knees, feet and legs to be standing up on a thick carpet than on a stage. Especially if you're playing a multi-set multi-hour job, it can really get physically taxing. Having a bit of cushion underneath you makes it that much easier to stay on your feet that long. If you've never done it before, you'd be amazed at how much of an endurance event a long show can be, and, the older you get, the harder it is to get your body through it, so you'll take any help you can get."
]
}
|
[] |
[] |
[
[],
[]
] |
||
5mp9n4
|
why can you hear the voices in the apartment above you so easily, but not the voices in the apartment below you?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5mp9n4/eli5_why_can_you_hear_the_voices_in_the_apartment/
|
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"Because sound travels through the solid medium ( the floor slab). On the floor above, people are directly in contact with the surface; while on the floor below, you're only depending on the noise traveling through air and noise traveling in air is divided into reflected, absorbed and transferred, major percentage of which, is reflected. "
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[] |
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||
2fozmj
|
if companies already know that most(if not all) people don't read terms of service, whats stopping them from hiding a hidden rule on page 500 of 3000 that makes you sign over all your possessions?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2fozmj/eli5_if_companies_already_know_that_mostif_not/
|
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"It would be considered an unconscionable term and thrown out in any reasonable court.",
"There's actually some precedent on EULA contracts, which are kinda similar to Terms of Service:\n\n_URL_0_\n\nFurthermore, it's not like this kind of legal situation just came about with computers; there have always been cases where a large corporation comes up with a very long contract that most customers sign without reading. There have long been legal protections for the \"small party\" in those cases.",
"Judges can throw out contracts or parts of contracts that they feel are unjust or unfair.",
"Because someone would find it and make it public knowledge. Then that company would be out of business or tied up in court for the rest of its existence. ",
"EULA are contracts of adhesion (it's dictated by one side, not the result of an equal negotiation). Contracts of adhesion will almost always be interpreted in favor of the side that didn't write it, and terms that aren't reasonably expected by the non-writing side are invalid.\n\nThis is partially why they are so long. They have to be VERY clear about the terms, because if something isn't clear, it will be read in favor of the consumer.",
"Aussie law student here! In all jurisdictions in Oz we have the Australian Consumer Law which contains provisions which, among other things, invalidate unfair terms in standard form consumer contracts. To determine whether a term is unfair, the court applies a three-pronged test: if the term would create a significant imbalance in the rights and obligations of the parties AND is not reasonably necessary to protect the legitimate interests of the advantaged party AND is detrimental to one of the parties it will be deemed unfair and severed from the contract. In analysing the term the court must consider the transparency of the term and the contract as a whole. It's also worth mentioning that this doesn't apply to terms which set out the subject matter of the transaction, determine an upfront price or are otherwise required under another statute.\n\nTL;DR: in Australia those terms would be invalidated in court per the Unfair Terms Laws, which are a part of the Australian Consumer Law statutory regime."
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[] |
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"http://en.wikipedia.org/wiki/End-user_license_agreement#Enforceability_of_EULAs_in_the_United_States"
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||
10dhv4
|
What's the average age of a species? What non-human factors determine when a species ends?
|
Someone told me that the average age of a mammalian species is around 8million years and that this explains why the Giant Pandas are becoming extinct as they've existed as a species for a lot longer than this.
Also, what are the differences in species age between mammalian and non-mammalian species? I remember reading that sharks as we know them today have remained unevolved for millions of years.
|
askscience
|
http://www.reddit.com/r/askscience/comments/10dhv4/whats_the_average_age_of_a_species_what_nonhuman/
|
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" > I remember reading that sharks as we know them today have remained unevolved for millions of years.\n\nWhat you might have read about were [living fossils](_URL_0_) which is a species that resembles a species from tens of millions of years in the past. For instance, sharks have changed little in form and function since they first evolved hundreds of millions of years ago. However this does not mean that they have stopped \"evolving\", species are always evolving. We know this because the species that were alive then are not the same as the species alive today. So, species come and go but the general body plan of a group of species might remain unchanged over many hundreds of millions of years. This follows the simple tenant \"if it isn't broke, don't fix it\".",
" > I remember reading that sharks as we know them today have remained unevolved for millions of years.\n\nNo living thing has remained unevolved for millions of years. Evolution is happening constantly, and it never stops happening.\n\nWhat you really read was probably something like \"sharks have looked pretty much the same for 400 million years\". This does *not* mean they didn't evolve.\n\nAnything that is alive is under constant selection pressure. Food and reproduction are not guaranteed, therefore it must constantly compete with members of its own species as well as other species for the resources available in its niche. In this competition, there are winners and losers, and only the winners get to pass on their traits to the next generation.\n\nThe fact that sharks *look* relatively unchanged simply means that their general body plan is very effective and efficient for their habitats and lifestyles. They retained that body plan not because selection pressure suddenly stopped, but because selection pressure *forced* them to retain that body plan, and any deviations arising from random mutations were culled.\n\nThis does not mean that they retained all their features - only some of them. Internally, sharks of today would be very different from those 400 million years ago. They would probably have significantly different biochemistries as well, since evolution also happens at the level of molecules. Just because sharks *as a group* have retained some similarity of form over hundreds of millions of years does not mean that any individual species of shark has lasted that long. In fact, I doubt that sharks are any more special than other large marine organisms in terms of the longevity of any given species.\n\nAccording to [Wikipedia](_URL_0_), the average timespan of marine vertebrate species is about 4-5 million years. I would expect sharks to fall within that range too.\n\nAccording to the same chart, mammals average about a million years. Pretty much everything falls within that range, from 1 million for mammals at the short end to 13 million for dinoflagelates at the long end.\n\nTo me, the key point would be the *mode* of extinction of the species. Did the species go extinct because it became too specialized for a niche, and then that niche was destroyed (perhaps by climate change, or an asteroid or whatever). Or was it outcompeted by a new species that evolved to occupy the same niche, or invaded its niche? Or perhaps it was neither, perhaps it was just a fast changing environment, and the species kept evolving (changing) to keep up with it, and over the course of a million years, those accumulated changes became so large as to justify calling it a new species?\n\nThe point is that there has to be some *reason* why a species goes extinct. Loss of habitat. Competition from another species. Some calamity that kills a lot of members of that species and reduces genetic diversity. Consequent diseases. Or simply small incremental changes over time that add up and it evolves into a different species. There is no clock running that says \"pandas have lived long enough, now their time is up\"."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Living_fossil"
],
[
"http://en.wikipedia.org/wiki/Background_extinction_rate#Measurement"
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|
27fpr9
|
why do people like jesse jackson and al sharpton march for white on black crime but not black on black crime?
|
Being from the black community this pisses me off - why is it that they feel they can blow white on black crime out of proportion but they aren't anywhere to be seen when black on black crime is happening - especially in chicago right now.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/27fpr9/eli5why_do_people_like_jesse_jackson_and_al/
|
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"I recall Bill Cosby speaking out against black on black crime. The media called him racist and some members of the black community accused him of turning his back on the people who got his career started. ",
"Because the racist tag they put on everything doesn't apply to black on black crime.\n\nIn response to the question \"How do we get rid of racism forever?\" Morgan Freeman simply said \"We stop talking about it.\" Jesse Jackson doesn't want to get rid of racism, he wants to profit from it. Same with all the other blacktivists out there. Its sickening. They don't care about actual, terrible racism that happens everywhere everyday by every color person. They just see a way to make money off of white people's guilt and extorts the shit out of it.",
"From the first couple pages of Google results, here's Jesse Jackson and black on black crime in [1984](_URL_2_), [1994](_URL_0_), [2007](_URL_4_), and [2012](_URL_3_)\n\nHere's Al Sharpton---my understanding the more \"radical\" and less generally respected of the two---in [2008](_URL_1_). \n\nIt's a simple fact of life that certain things take on more importance for certain groups and actors then for others. Sharpton and Jackson are primarily civil rights activists and, as such, are more concerned with events that have an element of direct racism, rather than any violence that effects the communities they represent. That doesn't mean they focus on those issues exclusively, naturally, but it shouldn't be a surprise that issues in that vein occupy most of their time. They are not the kings of the black community, nor are they just generally concerned with the community's well being. They are activists for a particular aspect of a particular cause---whether you agree with the cause, how they define it, or how they seek to advance it---and it makes sense that this would lead them to be more focused on issues tied to that cause. \n\nI don't know enough to defend either person, especially Sharpton, but in addition to the more cynical answers already presented here, there's also the above, and the fact that what efforts they do take don't necessarily fit the media narrative, and so don't get reported as widely. ",
"Hi everyone! Just a quick reminder, top-level comments must **not be jokes** and must contain some sort of explanation, not just a short phrase. Please write as objectively as possible when making an explanation, or at least note your bias in the post. ",
"Because talking about black-on-black crime won't sell. I'm black and I've done my homework about this issue.\n\nWhat /u/obliterayte said below is right, although stupid people are downvoting him.\n\nThose two race-baiters, Jesse Jackson and Al Sharpton, don't actually care about helping black people. They hurl the \"race card\" incessantly to make money. Most of the black people that support those race-baiters are poor and uneducated people who need to believe that someone actually cares about them, so they hurl money at them. But the thing is that Jesse Jackson and Al Sharpton don't actually care.\n\nTake a look at how they exploited the Trayvon Martin case. The way they made so much noise, you'd think that Trayvon was the first black boy to be murdered. Meanwhile, that same day, probably 100 black people were murdered in the state of Florida alone.\n\nThey are self-appointed \"leaders\" of nothing and they are quick to condemn racial injustice aimed at blacks. It doesn’t even matter if the prejudice is not real; those guys are on it. Sharpton is so skilled at ginning up crowds to protest injustice that his ability to pull together a rally of thousands in a matter of hours is called \"rent a demonstration.\" It is no secret that he uses his power as a tool of intimidation to encourage corporations to bend to his will.\n\n > Remarking on the only refuge in town, the New Orleans Superdome \"This looks like the hold of a slave ship\" -- Reverend Jesse Jackson asserted that the devastation inflicted on poor blacks by Hurricane Katrina proves America is a racist society. \"We don't see this kind of destruction in white or Jewish communities,\" said Jackson. \"Why is it always poor blacks who are hurt? It's because our racist society wants it that way.\" Jackson said 120,000 people in New Orleans make less than $8,000 a year. \"This is less than I charge for a single speech,\" Jackson pointed out. Jackson also criticized the role given to former presidents George Bush senior and Bill Clinton as coordinators for a fund raising effort following the disaster.\n\nThey __hardly__ talk about black-on-black crime because __*THEY DON'T CARE!*__\n\nThose two race-baiters have done more to set black people back than any modern non-black person ever could.\n\nThat slime-ball Jesse Jackson even attempted to shake down A & E over the whole Duck Dynasty fiasco by saying they had \"white priviledge\".\n\nThey don't deserve to be called \"civil rights leaders\" because _THEY ARE NOT_. They appointed themselves Judge, Jury, and Executioner; anyone who goes against them is called \"waycist waycist _WAYCIST!!1!!eleven!!!!1!_\".\n\nEDIT: I accidentally a word.",
"\nWhy do people use ELI5 to ask politically loaded questions?",
"two words. **race baiting**\n\nal sharpton and jesse jackson quite literally make money off of fueling hatred and racism between the masses. black on black crime just bring in the tv and book money that white on black crime does. \n\ndespite their previous anti-sematic remarks, tax evasion, and bigotry, many individuals blindly stand behind them.",
"Because that doesn't include their favorite card to play, the race card. Hard to say its the white man holding you down, when it was someone that looks real similar that did you wrong.",
"Because to extremist and race baiters like Al Sharpton the only civil rights that matters are those of the black community. Funnily enough he's doing absolutely NOTHING to further the black community in any positive ways. ",
"Because statistically, the percentage of crimes against black people that is committed by black people is the same as the percentage of crimes against white people committed by white people. \n\n\"Black on black crime\" is misdirection. Given that most violent crime is opportunistic, and that we live in a country that is highly de facto segregated, the racial split in crime makes sense. \"Black on black crime\" is not so much a problem as \"crime in black neighborhoods,\" and while that is a subtle distinction it is an important one. ",
"It's worth pointing out that \"black on black\" crime is most often a case of crime being committed relatively close to the criminals' home, and not racially based. Due to segregation throughout the USA, if a black person commits a crime, the victim will probably lives nearby, and the odds are the victim will be black as well. Same goes for white people. [Here's one (of many) articles that covers this](_URL_0_)",
"Do you all remember the racial slur Jesse Jackson said in his presidential campaign when he called New York Haimie-Town. Just saying. They both don't care about black on black crime it will not get their face on t.v. They are just here to stir the pot like fatty Rush Limbaugh and that fucking idiot Glen Beck. All of them serve no purpose other than to further polarize us as a people. Those four names are the face of racism. The way we beat racism is by not recognizing it. We should treat all people equal and hold everyone to the same standard. All violent crimes are crimes of hate therefore they are all hate crimes.\n",
"Because it advances the notion that there's a major race issue in America. And when you're in the \"civil rights\" business, if people don't need your product, you become irrelevant. ",
"this should be fun ",
"What we need to do is walk together against CRIME. If both communities join to fight racist crimes, then we can begin to see some progress.\n",
"They can't think of a way to get money out of white people for black on black crime.",
"because they are racist. I thought this was common knowledge ",
"Because they have made their reputation and money being poverty pimps and it's in their interest to ignore black on black crime because then they can't point the racist finger at anyone. They don't give a damn what happens in the hood because they can't use it to benefit themselves.",
"Because they both sold their soul to satan for wealth and fame, and now their duty to serve satan requires them to divide the humans with racism.",
"There are only 24 hrs in a day. \n\nPlus with white on black, you can take the time to learn the names of perp and victim. With black on black, you'd barely have the names documented before another new crime occurred. \n\n\\source: live in Richmond, VA - the Detroit of the south"
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[],
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"http://articles.baltimoresun.com/1994-01-18/news/1994018198_1_black-on-black-crime-jesse-jackson-black-and-white",
"http://www.nydailynews.com/news/crime/rev-al-sharpton-talk-violence-black-neighborhoods-article-1.292142",
"http://news.google.com/newspapers?nid=1454&dat=19841202&id=KUhOAAAAIBAJ&sjid=shMEAAAAIBAJ&pg=6992,432477",
"http://usatoday30.usatoday.com/news/opinion/forum/story/2012-06-12/jesse-jackson-gun-violence-marches/55527742/1",
"http://www.commondreams.org/archive/2007/08/28/3448"
],
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[],
[],
[],
[],
[],
[],
[
"http://www.yourblackworld.net/2013/07/black-news/black-on-black-crime-you-say-white-people-kill-each-other-just-as-much-as-black-people-do/"
],
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|
1ka5ft
|
elon musk's/tesla's hyperloop...
|
I'm not sure that I understand too 100% how it work, so maybe someone can give a good explanation for it :)
_URL_0_
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1ka5ft/eli5_elon_musksteslas_hyperloop/
|
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"Ooh, I understand it quite well :)\n\n[pdf link](_URL_0_)\n\nMultiple special vehicles ride through the tube. This tube, initially stretching from San Francisco to Los Angeles, has low air pressure so that the vehicles don't have to use so much power to go through it.\n\nThe vehicles have a big electric motor, a turbine and a battery. They use this to keep themselves at speed, but not to accelerate. To accelerate, [Linear induction motors](_URL_1_) are used. To decelerate, you can either hook up the turbine to a generator, slowing it and charging the battery, or use more Linear induction motors.\n\nThe vehicle has its battery pack in the back and a ~450hp electric motor in the front.\n\nThe tube will also be equipped with solar panels on its top, which will produce more power than the system needs.\n\nThe turbine not only sucks air in at the vehicle's front, but this air is pressed to the vehicle's bottom, giving it an air cushion.\n\nI did not go through many of the Hyperloop's safety considerations. Maybe somebody else will...\n\nTL;DR: Air cushioned vehicles go through a low pressure tube. They Accelerate, and maybe decelerate, using linear motors.",
"If you're familiar with Kerbal Space Program, you probably keep an eye on the atmosphere meter when you're doing a launch. The higher up you go, the thinner the air is. You don't need as much propulsion to change your velocity once you get out into space. But on land, when you're trudging through the thick atmosphere, it takes a lot of energy to accelerate.\n\nThis is the reasoning behind the *edit: near* vacuum tube idea. Less drag. Requires less energy to move a capsule of people. Less energy to keep a vehicle at cruise speed.",
"Passengers ride in capsules inside a tube.\n\nThe tube is kept at a low air pressure, but not nearly a hard vaccuum.\n\nEach capsule has a fan at the front that sucks in what little air there is in the tube.\n\nSome of the air gets pushed out the back as thrust, ~~but most~~ and some gets pushed out pads on the bottom called \"air bearings\". This lets the capsules float inside the tube, the way an air hockey puck floats on an air hockey table.\n\nThe capsules are powered by big onboard batteries like the ones in electric cars.\n\nIn order to travel at hundreds of miles per hour, the capsules basically get shot out of a rail gun. If you've ever ridden a roller coaster that shoots you up the hill quickly (for instance, [DCA's California Screamin](_URL_0_)), it's the same technology.\n\nIn order to power the rail guns, solar panels installed on top of the tube will generate electricity. These will generate more electricity than the system needs to run.",
"watch the monorail episode of the simpsons, your welcome",
"My question: what's the emergency plan? How do vehicles stop if the tunnel breaks (earthquake, terrorism, whatever)? How do they know they have to stop? How do they evacuate the pods?",
"Cheap tube. Expensive vehicle.\n\nVehicle sucks air from front, uses it to create air-like-skis. Goes fast. Brings people to places.\n\nBeats railway.",
"I have a supplemental question that I haven't seen answered so far: is the hyperloop comparable at all to traditional rail for movement of freight?",
"There will need to be a very well thought out Reliability Maintenance strategy. I can't think of an industry including space, nuclear, aviation, maritime, rail, and petro-chem that contains the same maintenance challenges as this project. I have some issues in mind and would like to hear your thoughts.",
"ITT this thread is full of non-engineers with no idea what they are talking about"
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[] |
[
"http://www.teslamotors.com/blog/hyperloop"
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"https://en.wikipedia.org/wiki/Linear_motor"
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3v3yes
|
why is most of the juice available in the supermarket a mix with cranberry juice?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3v3yes/eli5_why_is_most_of_the_juice_available_in_the/
|
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"I also want to know this. I went to the store one day because I wanted juice that didn't taste like cranberry. So naturally I tried to find juice without cranberry in it. The only one I could find was cherry juice mixed with apple juice. Guess what. That mix tasted exactly like cranberry juice."
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[] |
[] |
[
[]
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||
6ebhwd
|
Where do Newtonian physics stop and Einsteins' physics start? Why are they not unified?
|
Edit: Wow, this really blew up. Thanks, m8s!
|
askscience
|
https://www.reddit.com/r/askscience/comments/6ebhwd/where_do_newtonian_physics_stop_and_einsteins/
|
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"They are unified, in the sense that when the velocity is slow enough, both of them give the same answer (you can express this formally for example through the use of Taylor series). They only start to diverge when velocities approach the speed of light and Newtonian physics is no longer an accurate description of nature.",
"As a rule of thumb there are three relevant limits which tells you that Newtonian physics is no longer applicable.\n\n1. If the ratio v/c (where v is the characteristic speed of your system and c is the speed of light) is no longer close to zero, you need special relativity.\n\n2. If the ratio 2GM/c^(2)R (where M is the mass, G the gravitational constant and R the distance) is no longer close to zero, you need general relativity.\n\n3. If the ratio h/pR (where p is the momentum, h the Planck constant and R the distance) is no longer close to zero, you need quantum mechanics.\n\nNow what constitutes \"no longer close to zero\" depends on how accurate your measurement tools are. For example in the 19th century is was found that Mercury's precession was not correctly given by Newtonian mechanics. Using the mass of the Sun and distance from Mercury to the Sun gives a ratio of about 10^(-8) as being noticeable.\n\nEdit: It's worth pointing out that from these more advanced theories, Newton's laws do \"pop back out\" when the appropriate limits are taken where we expect Newtonian physics to work. In that way, you can say that Newton isn't *wrong*, but more so incomplete.",
"Einstein's physics holds in all places that Newtonian physics does, but not the other way around. That is to say: when speeds are slow, Einstein's physics simplifies to Newton's. At larger speeds though, Einstein's physics is capped by the speed of light, whereas Newtonian physics makes no such prediction.",
"Relativity is always correct. Newtonian mechanics are an approximation that usually works well enough at low speed and gravity. Think of it like how `f(x) = sin(x)` is approximated by `g(x) = x` when x is near 0.\n\nWhether or not you can get away with the error just depends on how accurate you need to be, and how far from 0 speed and gravity you are. Newtonian mechanics was good enough to land men on the moon, but we need relativity for GPS satellites to be accurate.",
"Think of your hand without the last segment that has your fingernails, that is Newtonian physics. Einstein gave us fingertips. Einstein's physics are an extension of Newtonian physics allowing us to explain in greater detail our universe and how it works. \n\nThe great thing about science, what ever has been proven to work in the past through testing, still works in the new theories. It's more a new understanding in greater detail as to why the universe does what it does, which can lead to even new discoveries.",
"They are totally, 100% unified. Newtonian physics is the c-- > infinity limit of special and general relativity. \n\nThat is, Newtonian physics is a reasonably accurate approximation as long as all speeds are small comparing to the speed of light and all energies involved (e.g. the absolute value of the gravitational potential energy) are small compared to mc^2 . \n\nWhat constitutes \"small\" depends on the precision of the measurements; atomic clocks will be able to detect the difference in the rate of passage of time between the bottom and the top of a building, while a regular watch would probably not be able to even withstand the kind of gravity you'd need to detect it's effects on time.",
"There are a lot of good answers. But most of them leave parts out. You can get back *Newtonian* physics by approaching certain boundary conditions. It is not that Newtonian physics and Relativistic physics are separate. They just describe things at different levels of detail. That detail has been laid out by others so I will not repeat it here. The relevant thing as to why we don't just run around using Relativistic calculations all the time is that they are significantly more complex. So, if they are not needed because the results are effectively the same, why not use the easy method? \n\nAs another user noted in a very negative manner, our understanding of physics is still advancing as the nature of sciences will do. So, there may well be more nuanced understandings of the universe to come. But, an important caveat, that he seems to think trivial, is that unlike Aristotlean physics, ours has been tested and retested. So much so that it will always be valid under the proper circumstances. The problem is that our observations have advanced and so our understanding has as well. Pre-Newtonian physics relied on theorycrafting and not matching it to observations. So while they are not still relevant, Newtonian physics always will be because it describes the basic world we live in well. It just does not explain the world we don't live in well (ie, extreme gravity, close to the speed of light, or quantum). ",
"I think the question understandably misunderstands the relationship between these two physics. It's easy to fall into the idea that Newtonian physics is the normal physics and Einsteinian physics kicks in when things are travelling at around the speed of light. \n\nA better way to think of this is as Einsteinian physics having replaced Netwonian physics. Einstein's equations work like a spectrum- at the zero speed etc they work exactly like classical physics (to the point you can derive the classical laws of motion from Einstein's with the correct conditions). These conditions can never be met in reailty so Newton's laws are actually an idealised situation, a bit like a assuming a \"spherical cow\". As the body speeds up, the relativistic properties become ever more significant (in reality they are always there). At the speeds humans normally deal with the relativistic effects are so small you can't normally see them, which is why Newton's laws appear to work.\n\nTL:DR; they are unified, but Newtonian physics is a special case within Einsteinian physics.",
"Because you need more answers ^^(/s) I'll answer your question a bit more directly: \n\nEinsteins' laws don't start, they are always at play, and Newton's laws progressively breakdown as relative velocities approach the speed of light. It's technically your call when to stop using them but the closer to C the relative velocities are the less accurate your calculations will be.",
"Newtonian physics is wrong but for most applications, the error is acceptable. NASA's Apollo program used Newtonian equations entirely (they did it with pen and papers too) and still landed on the Moon successfully many times.\n\nNow that computers are so fast that your cheap smartphone is hundreds of time faster than what they used back in the 1960s and 1970s, if you want to calculate the force, distance, time, speed and acceleration, a software can give you the most accurate results via Einstein's equations just as fast as Newtonian equations. It's just with Einstein's equations, you must give it a few more inputs.\n\nAs for NASA that now they send time critical satellites such as GPS, they use a full blown simulation suite for trajectory and time window calculations, and the software implementation must not use Newtonian equations. Different times, different acceptability. ",
"Newtonian physics stops if you want accurate GPS readings. The atomic clocks are so sensitive that if you didn't use both Einstein's General relativity ( To deal with the mass of the Earth) and special relativity ( the relative speeds of the satellites) you would be out at a rate of about 10 kilometers each day. see also _URL_0_",
" > Where do Newtonian physics stop and Einsteins' physics start? Why are they not unified?\n\nSet theory. The set \"Einstein physics\" is larger *and* completely encompasses the set \"Newton physics\". So, the term \"unified\" doesn't quite apply here.\n\nYou were maybe thinking of General Relativity and Quantum Mechanics - these two are (For all we know.) both NOT a set that contains the other, and \"unification\" would mean to discover a new set that encompasses the both of them.",
"Newton's physics are just plain old wrong; Einstein's equations are correct. However, for most ordinary calculations, Newton's equations are more than accurate enough, and are vastly easier to calculate. Thus, we just use Newtonian physics when we're not dealing with objects that are extremely massive or going extremely fast. If you start dealing with space stuff, or start shooting things around at a reasonable fraction of the speed of light, then you need to start using Einstein's equations.",
"Einsteinian physics is always applicable, but too complex for smaller calculations. Newtonian physics are way too simple to convey much in larger-scale (or *really* small scale) problems.\n\nBasically, Newton is right if the calculationis about everyday occurences, Einstein is always right.",
"In the simplest terms: you can use Newtonian physics up until you need to factor relativity into the equation.\n\nSo unless you're dealing with energy levels capable of curving spacetime you will be fine using Newtonian physics.",
"Most here are focusing on the equations used to calculate physical movement, which is a very important difference, but another major difference between Newtonian physics and Einstein's general relativity is in the understanding of space and gravity. For Newton, space is absolute, meaning that it is static and empty. Whereas for general relativity, space is relative, meaning that space itself distorts and bends. For Newton gravity works, but there is no account of how. Einstein's general relativity theorizes that gravity works by bending the fabric of space toward larger objects which causes smaller objects to fall toward them. By this theory, you are falling and accelerating toward the earth all of the time, but the surface of the earth is impeding that acceleration. These are contradictory accounts of space and therefore cannot be unified, which is why the theory of general relativity has replaced Newtonian physics, though Newtonian equations are still employed when practical to do so - that is, when the more complex equations of relativity wouldn't bear a significant difference. ",
"Einstein's physics IS physics. But the changes imposed by it are meaningless to things that aren't tiny or traveling very fast. For instance everyone has a harmonic frequency. We all absorb and emitt radiation but we absord and emitt so little as to be completely irrelevant. All physics theories are just models of reality. And all models can break down under certain conditions. So when Newtonian physics broke down it didn't mean that Newton's models are bad, they just reached the limit of their predictive power. So we made some new models that did fit with the observed phenomenon and have been working rather well ever since. But they may one day break down also and we'll need to create a New model to characterise the phenomenon we see.",
"They basically are. An analogy: for all smallish scale purposes, you can assume the earth is flat. But it's not, and if you're trying to launch satellites, you need to deal with the fact that it's a ball floating in space. \n\nLikewise, for many purposes, you can assume Newtonian physics is correct, but it's not, and if your setting up GPS satellites, for example, you need to correct for time dilation. \n\nYou may be thinking relativity and Quantum physics, in which case the issue is with gravity and very, very small things. ",
"Have you done calculus? If so, have you seen Taylor series? For those that haven't, Taylor series are essentially ways of representing difficult to deal with functions as approximations using polynomials. For functions that aren't already polynomials, they require infinitely many terms to be entirely correct, but can get pretty close with lesser degrees, but will diverge as you get away from the center of the approximation. \n \nNewtonian physics is analogous to a 5th order Taylor series and Einsteinian physics is analogous to an 11th order Taylor series (slightly arbitrary numbers). Essentially, Einstein's theories hold for a much broader range than Newton's do (if you want to see this visually, plot sin(x), and then plot the 5th order and 11th order Taylor polynomials on top of it). Special relativity holds on nearly any energy scale, Newtonian mechanics holds on \"normal\" energy scales, I.e., those that are relatively close to what we experience as humans. General relativity is our current theory of gravity that supersedes Newton's theory of gravity when dealing with massive objects or fast objects, it describes phenomenon not consistent with Newtonian gravity, such as gravitational lensing (light being bent, or lensed, around massive bodies), which doesn't make sense from Newton's perspective because light is massless, or the precision of the perihelion of Mercuries orbit (essentially the way Mercuries orbit fluctuates is weird because it is so close to the sun). ",
"The areas of physics that are not unified are quantum mechanics and relativity. At large energies and small distances they give conflicting results for their predictions. They do not mesh well and it is the biggest unresolved problem in physics right now.",
"Newtonian physics is just a really good approximation of interactions we see on a daily basis. The reason it is still taught even though it is only approximate (not actually correct) is because the calculations needed to represent what is actually happening are prohibitively complex. That said the limits for Newtonian physics occur when you get to the atomic scale, the super massive scale (planets with very high gravity), or when approaching the speed of light. Been a while since I studied anything but newtonian so correct me if I am wrong."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[
"http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
|
4l3tp8
|
Why was Scipio Africanus so disliked by his political peers?
|
I know he basically had to flee Rome to stop getting tried on bogus charges. What made the animosity rise to that level? Shouldn't they have been grateful to him?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4l3tp8/why_was_scipio_africanus_so_disliked_by_his/
|
{
"a_id": [
"d3kfsoi"
],
"score": [
25
],
"text": [
"Scipio's not exactly the only Roman aristocrat to be prosecuted following great service to the state. Actually, it's kind of common. The Roman aristocracy relied on the individual magistrate or promagistrate to get anything done, but was highly suspicious of the individual standing head-and-shoulders above his peers. The individual of unusual *dignitas* and *auctoritas* through his actions was expected to retire from public duties, or voluntarily accept an advisory role for the next generation. This of course did not happen in practice often, even in Scipio's lifetime. Scipio was the political enemy of Marcus Cato, who constantly opposed him at the end of his life, with his characteristic persistence. Part of this was because the nobility, suspicious as usual, did not look kindly on his enormous prestige. Scipio really did have extraordinary *dignitas* following Zama--there built up around him soon after the \"Scipionic Legend,\" in which Scipio was said to have performed various miraculous deeds and to have been the son of a god (usually Jupiter). For example, Livy says that there was a story that Scipio was conceived when his mother was visited by a giant snake--Livy thinks the story is ridiculous, and points out that it was already being told of Alexander, but certainly that gives an idea of the sort of legend that was built up around Scipio within only a short time. Besides the rather unwelcome influence of the growing Scipionic Legend the senatorial class did in fact have some reason to feel insecure about Scipio. Scipio's later career was relatively unremarkable, but not really for want of trying. He held the censorship in 199 and was *princeps senatus* twice in 194 and 189, both somewhat expected of a consular, though Scipio wasn't exactly an ordinary consular. Scipio was, however, consul for a second time in 194, and lobbied for the right to command the war against Antiochus III, a motion which was knocked down in the senate. Scipio did not fight at Magnesia, but he volunteered against Antiochus as legate under his brother in 190. It's not hard to see why Scipio, the quite literally legendary victor over Hannibal and recent consul for the second time, might be suspected by the senatorial class of really being the one pulling the strings in the war, especially when it was Scipio who arranged the peace with Antiochus. Certainly the senatorial class was uncomfortable with the freedom with which Scipio threw his reputation around, and they were not totally unjustified, as Scipio's behavior was not very in character with the expectations of a member of the senatorial class. Following his return from the war against Antiochus Scipio (and his brother) were both attacked by Marcus Cato in the courts--clearly the conduct of this war, and the suspicions of misconduct during it, were the last straw, so to speak."
]
}
|
[] |
[] |
[
[]
] |
|
gmgjq
|
Evolutionary, will we be fatter or thinner in the future?
|
askscience
|
http://www.reddit.com/r/askscience/comments/gmgjq/evolutionary_will_we_be_fatter_or_thinner_in_the/
|
{
"a_id": [
"c1omnbc",
"c1omq4p"
],
"score": [
2,
11
],
"text": [
"I think we are a few decades away from drugs that will safely control fat accumulation.\n\nIf that occurs, the genetics will become irrelevant.",
"How fat we get is more of a reaction to our environment rather than our evolution. A creature with a lot of food available will (assuming they eat it) get fat, while one that has to expend a lot of energy to get food will be lean.\n\nFrom an environmental point of view, animals who are out in the wild often have a specific need to being fat or thin to have an advantage to pass on their genes. Seals for example are unlikely to be able to breed if they haven't got enough fat on them (meaning they die of heat loss in their arctic environment). Cheetas on the other hand would be unlikely to catch their prey if they got fat, so that keeps them lean.\n\nHumans don't really have that aspect to their evolutionary chances to pass on their genes. Both fat and lean people are able to grow to an age where they are able to pass on their genes - if anything were to be included it would likely only be aesthetics, but that itself rarely results in children these days (as in casual sex with an attractive partner)."
]
}
|
[] |
[] |
[
[],
[]
] |
||
21jj18
|
is the buddha still 'alive'?
|
I've been interested in Buddhism, I've been trying to research what people believe the fate of Buddha is. Every source (mostly yahooanswers) says that he ended his eternal suffering, and that's about it. Is he still being reincarnated?
The popular epic ' Journey to the West' has him depicted as better than the Jade Emperor because the Buddha is the one only one that traps the Monkey King. So he is some-sort of super being in this case...
What do Buddhist believe happens after they die after they reach Enlightenment?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/21jj18/eli5is_the_buddha_still_alive/
|
{
"a_id": [
"cgdnkw6",
"cgdyxpe"
],
"score": [
3,
2
],
"text": [
"There are different buddist schools. In Theravada buddhism, anyone that reaches nibanna is removed from circle of life and is never born again.",
"Interesting note, reincarnation was around before Buddhism was founded. Borrowed ideas?"
]
}
|
[] |
[] |
[
[],
[]
] |
|
2a84rc
|
what was the fault in brazil's defense ?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2a84rc/eli5_what_was_the_fault_in_brazils_defense/
|
{
"a_id": [
"cisey62"
],
"score": [
4
],
"text": [
"their strategy of panicking and running around in a state of confusion, while bold, was ultimately spectacularly unsuccessful "
]
}
|
[] |
[] |
[
[]
] |
||
5dkc6d
|
is the world really round\spherical (exactly 360 degrees)?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5dkc6d/eli5_is_the_world_really_roundspherical_exactly/
|
{
"a_id": [
"da57ibb"
],
"score": [
2
],
"text": [
"It's not *exactly* spherical. If it were, there would be no variations in terrain like mountains or valleys.\n\nIn fact the Earth is slightly shaped like an oval. But it's mostly spherical."
]
}
|
[] |
[] |
[
[]
] |
||
5vwj41
|
special relativity says the mass of a moving body _url_0_ has the mass of the universe been increasing since the big bang?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5vwj41/eli5special_relativity_says_the_mass_of_a_moving/
|
{
"a_id": [
"de5hxxk"
],
"score": [
4
],
"text": [
"I'm assuming you think the mass of the universe is increasing because of expansion. You can't talk about 'the universe' as an object, even taking into account relativity, because the universe is the thing that all the objects are in. The expansion of the universe is talking about the space itself expanding, so it doesn't really make sense to talk about the mass of the universe itself. While objects are moving away from each other due to expansion, it's because it's like the space itself is moving, not the objects.\n\n(My first ELI5 answer, constructive criticism is welcome)"
]
}
|
[
"increases.So"
] |
[] |
[
[]
] |
||
79fs3x
|
What is the farthest direct parallax measurement of an object?
|
I haven't been able to find any clear reporting on the Gaia mission, even though it was supposed to be able to directly measure a lot farther than before.
|
askscience
|
https://www.reddit.com/r/askscience/comments/79fs3x/what_is_the_farthest_direct_parallax_measurement/
|
{
"a_id": [
"dp1qp31"
],
"score": [
12
],
"text": [
"GAIA hasn't released parallax measures of distant stars yet, that's going to take some more time. While optical parallax has been limited to the nearest 100 pc or so, parallax from radio measures can go significantly further by using interferometry, where multiple radio telescopes across the globe are linked up to act as a single giant telescope, the Very Long Baseline Interferometer and the Event Horizon Telescope being the main examples (These use many of the same physical dishes). \n\nOn top of the positional accuracy from a telescope the size of the Earth, the position of a radio source is also uncertain by an amount inversely proportional to the signal to noise. I.e. the brighter the source is, the better you know the position. I know [microquasars such as V404 Cyg and GRS 1915+105 in our own galaxy have had their distances measured by trigonometric parallax to a distance of at least 8600 pc](_URL_0_) (almost 100x better than optical!), but I don't know what the actual \"world record\" is. Anything in our galaxy of sufficient radio brightness could have its distance measured by parallax, but past 10 kpc, the density of stars starts to dive precipitously. \n\nSo some objects as far as GAIA can go have already had their distances measured. GAIA scores not in going further, but doing it reliably for a great many ordinary stars. "
]
}
|
[] |
[] |
[
[
"http://adsabs.harvard.edu/abs/2014ApJ...796....2R"
]
] |
|
33awbu
|
do animals (especially those who mate for life) feel love like we do?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/33awbu/eli5_do_animals_especially_those_who_mate_for/
|
{
"a_id": [
"cqj64x1",
"cqj65ks"
],
"score": [
2,
2
],
"text": [
"What happens when we die? Nobody can actually perceive the reality of a dead person just like nobody can perceive the reality of a swan. This question will only bring opinionated answers not factual ones.",
"Hard enough to prove love really exists in humans. But there have been instances of dogs weeping over dead relatives or partners. \nCrows attacking people who captured or killed other crows in their group. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
3wgxrq
|
the height of the average american male has risen roughly 3 inches in the past 200 years. is this an example of evolution, coincidence, or something else?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3wgxrq/eli5_the_height_of_the_average_american_male_has/
|
{
"a_id": [
"cxw4vxm",
"cxw51u4",
"cxw53ak",
"cxw59nn"
],
"score": [
10,
7,
5,
3
],
"text": [
"It is probably due to better nutrition. People are more likely to reach their genetic potential.",
"People are fed better. 200 years ago you were rich if you got to eat meat every day. Now, everybody does.",
"Mostly it is a result of nutrition. We have really only had a stable food supply as a species for the last 200 years. ",
"Nutrition and medicine mostly.\n\nUnderfed children who battle polio are going to wind up a little shorter."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
205i37
|
What was the impact of the First World War on eastern Europe
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/205i37/what_was_the_impact_of_the_first_world_war_on/
|
{
"a_id": [
"cg0cjxg"
],
"score": [
4
],
"text": [
"World War I had some pretty big consequences for Eastern Europe in all sectors of life, including the economy, culture, and politics. I'll focus on the most obvious consequence: the redrawing of borders in Eastern Europe. The dissolution of the of the Austro-Hungarian, German, and Russian Empires allowed the Allies to pursue a policy of self-determination for national minorities as laid out in [Woodrow Wilson's Fourteen Points](_URL_1_).\n\nHere is a [map of Europe in 1914](_URL_3_).\n\nAnd here is [Europe five years later](_URL_6_), after the war was concluded.\n\nThe three main treaties we're going to be looking at here are [Versailles](_URL_0_), [Saint-Germain-en-Laye](_URL_2_), and [Trianon](_URL_5_), which redrew the borders of [Germany](_URL_4_), [Austria, and Hungary](_URL_7_), respectively. \n\nIn the new map, we can see the emergence of several new nations, including: Austria, Hungary, Czechoslovakia, Yugoslavia, Poland, Lithuania, Latvia, Estonia, Finland, and the Free City of Danzig. Additionally, we see a greatly enlarged Romania and a slightly smaller Bulgaria, whose path to the Aegean now firmly in the hands of Greece. This map is, however, a little bit misleading as it implies that the USSR at this time is firmly established, when in reality it was in the midst of the Russian Civil War (which is its own big can of worms). I'll try to give those countries a quick mention too. I think the easiest way to go about this is to examine each country really quickly, looking at where its territory came from and because of what treaties. Obviously people can go into more detail about specific countries; this is just a brief(ish) overview.\n\nEstonia, Latvia, and Lithuania: Formed from territory of Russia and Germany\n\nRussia formally pulled out of World War I under Bolshevik leadership with the Treaty of Brest-Litovsk in early 1918. Originally the Germans had planned to establish puppet governments under the control of Baltic Germans (who owned most of the land), but obviously Versailles halted those plans. With the retreat of most German forces from the region, the Bolsheviks moved in in an attempted to reassert their claim to the lands that they had so recently surrendered, and thus the Baltic states became a part of the Russian Civil War. In general, the nationalists of these countries sided with the Whites (anti-communist forces), through not without some issues. Eventually, the Bolsheviks came to realize that holding on to the region was simply too difficult, thanks in large part to Estonian, Latvian, and Lithuanian troops using supplies from the Western Allies.\n\nPoland: Formed from territory of Germany, Russia, Austria, Hungary\n\nPoland emerged from the war with territory from all the major empires. Like its counterparts in the Balkans, it too was drawn into the Russian Civil War, during which Poland allied with the Whites. After initial success in Ukraine, the Poles were eventually beaten back by the Soviets, all the way to Warsaw. Fortunately for Poland, the Red Army was decisively defeated at Warsaw in August of 1920. The Polish government also got into a squabble with Lithuania over Vilnius, which it held throughout the inter-war period. The question would not be settled until 1939 when the Soviets returned Vilnius to Lithuania after they invaded Poland. Germany's borders with Poland were set in Article 27 of Versailles. It should be noted that the creation of the “Polish Corridor” between Germany and East Prussia was one of the main problems the Nazis had with the treaty.\n\nCzechoslovakia: Formed from territory of Austria, Hungary, and a little bit of Germany\n\nThe Czechs and Slovaks are two distinct ethnic groups, but after the Pittsburgh Agreement (yay, hometown!) leaders from both communities agreed on the formation of an independent Czechoslovakia from the Austro-Hungarian Empire. Unlike the previous countries, Czechoslovakia was not involved in the Russian Civil War and its independence did not involve significant conflict beyond the First World War itself. Czechoslovakia was officially recognized with Saint-Germain.\n\nRomania: Romania's loyalty to the Allies earned them a sizable chunk from Hungary, as a result of Trianon. This eventually led to problems due to ethnic Hungarians being stuck in Romania. Hungary swiped some of their old territory back during WW2, but that was eventually returned, and it remains that way today.\n\nYugoslavia: I'm unfortunately not all that well-versed in what went on in Yugoslavia at the time. I can tell you that it was the culmination of the efforts of the Pan-Slavic movement, and that it included former territories of Austria-Hungary and Serbia, but that's about it. It was a monarchy, with a Serbian king.\n\nI just want to point out, that for all the crap Versailles gets for being harsh on the Germans, everyone seems to forget that Austria and Hungary were *gutted* by their treaties. Following WW1, both Austria and Hungary ceased to be major powers, and the industrial heartland of the empire, Bohemia, was now part of Czechoslovakia. \n\nI'm sorry if I've forgotten anything, but I think I got most of the points.\n\nDavies, Norman. *Europe: A History*. Oxford: Oxford University Press, 1996.\n\nDziewanowski, M. K.. *Russia in the Twentieth Century*. 6th ed. Upper Saddle River, N.J.: Prentice Hall, 2003.\n\n"
]
}
|
[] |
[] |
[
[
"http://avalon.law.yale.edu/subject_menus/versailles_menu.asp",
"http://avalon.law.yale.edu/20th_century/wilson14.asp",
"http://www.austlii.edu.au/au/other/dfat/treaties/1920/3.html",
"http://www.emersonkent.com/images/europe_1914.jpg",
"http://www.johndclare.net/images/Versaillesmap_USHMMger71020.gif",
"http://wwi.lib.byu.edu/index.php/Treaty_of_Trianon",
"http://www.emersonkent.com/images/europe_1919.jpg",
"http://upload.wikimedia.org/wikipedia/commons/5/50/Dissolution_of_Austria-Hungary.png"
]
] |
||
4vw5ts
|
how are we able to animate so much more realistically now than ten, fifteen, etc. years ago?
|
What about our technology is making it easier? Is it still people doing the animating?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4vw5ts/eli5_how_are_we_able_to_animate_so_much_more/
|
{
"a_id": [
"d6234ds"
],
"score": [
2
],
"text": [
"It's due to a combination of better software and better hardware.\n\nAs animation became more popular, newer and better methods were developed. For example, the way animators now move a person is through a inverse or forward kinematics rig. This basically lets the animator assign \"bones\" to different parts of a model, and have them all connected. So if the animator wants to move a hand, they just drag the hand, and the computer will automatically fill in all of the in between frames and automatically move the elbow and the shoulder and the arm to make it more realistic. Years ago before this was developed, an animator would have to move every joint individually, one frame at a time. Or earlier in 2d animation, draw every frame by hand.\n\nAlso, as computing technology developed, faster processors and graphics cards in computers allowed for more advancements in animation software. Trying to run modern animation software on an eight year old computer probably wouldn't work."
]
}
|
[] |
[] |
[
[]
] |
|
3rlxgv
|
What tactics did medieval European armies use when fighting horse archers? Did European armies ever employ horse archers?
|
Medieval Armies that employed horse archers seemed to have a lot of success in battle, The early Hungarians raided most of western europe, the turks defeated the byzantines at manzikert, and Saladine's crushing victory over the crusaders at Hattin. These battles are usually used to illustrate how the agile horse archers were able to say out of range of their slow, plodding oppenents and pepper them with arrows until they either routed or were run down. However, I read that the slower, more heavily armed Germans were able to defeat the Hungarians at lechfield and the crusaders and Byzantines were able to do the same and score many victories against Turkish and arab horse archers. How were the heavily armored slower armies able to to pin down and defeat armies using horse archers?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3rlxgv/what_tactics_did_medieval_european_armies_use/
|
{
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"text": [
"The Byzantines used Horse Archers as well as Cataphracts. They adapted their armies to be very Calvary based due to their fighting with the Sassanids.\n\nThat said horses were very expensive to buy and maintain and horse archers were not all that effective in the heavily wooded German regions. Horse archers need a lot of room to maneuver to be effective, so they were usually beaten when their amazing mobility could be restricted.\n\nTactics to reduce the mobility of horses and horse archers at least in the early medieval period would have been trenches dug that would be covered by the dust created by an army.",
"A fairly good example of a battle won by medieval European armies against horses archers would be the battle of Dorylaeum (1097) fought by the armies of the first crusade against the Turks led by Kilij Arslan.\n\nThe battle was described in the Gesta Francorum et aliorum Hierosolimitanorum (\"The deeds of the Franks and the other pilgrims to Jerusalem\"), whose author was a first-hand witness serving in the army of Bohemond of Taranto and is available here: _URL_0_\n\n\nThe vanguard of the crusader army was attacked by an important turkish force of horse archers. Taken by surprise, the crusaders were unable to engage the opponent skirmishers (although their heavy armors protected the knights from most arrows, their horses and less armoured foot soldiers were not as lucky), and Bohemond of Taranto had to organize a somewhat desperate defense. \n\nAs the day went on, the Turks became more agressive, trying to press their advantage in order to break their opponents morale. However, in doing so, they became vulnerable to a surprise attack: the rear guard of the first Crusade, led by Bishop Adhémar of Le Puy , made it into the battlefield at this moment and managed to close the gap with the bulk of the turkish force. \n\nIn melee combat, the average french or norman knight was extremely favoured against the lightly armoured horse archers. By outflanking the turkish troops, the crusaders won the battle and opened the road to Antioch. Proper use of terrain and the element of surprise were the key factors to most victories the first crusaders won against forces using large amounts of horse archers.\n\n\n\nSources: \n\n**Z.Oldenbourg**, *Les Croisades*, Gallimard, 1965, p 147-151\n\n**Louis Bréhier**, *Gesta Francorum et aliorum Hierosolimitanorum*, 1964. French translation.\n\n**R. C. Smail**, *Crusading Warfare, 1097-1193*, Cambridge University Press, 1995",
"In the Battle of Jaffa, during the 3rd Crusade, crossbowmen proved very effective against Saladin's horse archers.\n\nSaladin had taken the town of Jaffa from the Crusaders, but the citadel held out. Richard the Lionheart attacked the town from the sea and drove the Saracens out. \n\nSaladin then attempted a battle with his horse archers to retake the town. The clash between the two armies took place in the fields outside the walls of the town.\n\nRichard's army consisted of about 54 knights, a few hundred infantry armed with spears, and 2,000 Genoese crossbowmen.\n\nThe crossbows shot the horse archers to pieces. Saladin was said to have lost 700 men and 1500 horses. Crusader casualties were two men.\n\nIt was this victory which led to the peace which concluded the Third Crusade."
]
}
|
[] |
[] |
[
[],
[
"http://legacy.fordham.edu/halsall/source/gesta-cde.asp#dory"
],
[]
] |
|
3oe55s
|
Does raising acetylcholine increase or decrease dopamine?
|
I'm having a difficult time finding legitimate studies online and unofficial sites take either one side or the other. Anyone care to clear up the mystery?
|
askscience
|
https://www.reddit.com/r/askscience/comments/3oe55s/does_raising_acetylcholine_increase_or_decrease/
|
{
"a_id": [
"cvwh63l"
],
"score": [
2
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"text": [
" Where? Acetylcholine is not generally just freely diffusing throughout the CSF, as there is a relatively large amount of chemicals that break it down diffuse in the CSF. Also it's not like you could just eat acetylcholine and get more at your synapses or something."
]
}
|
[] |
[] |
[
[]
] |
|
1786ki
|
Why does an aluminum pot turn dark grey if left on the stove for too long?
|
After leaving an aluminum pot boiling for awhile I returned to find that the area covered in water turned a dark grey.
|
askscience
|
http://www.reddit.com/r/askscience/comments/1786ki/why_does_an_aluminum_pot_turn_dark_grey_if_left/
|
{
"a_id": [
"c83aoob"
],
"score": [
2
],
"text": [
"Oxidation, Al2O3 is grey."
]
}
|
[] |
[] |
[
[]
] |
|
442tyy
|
When did women first start outnumbering men as teachers?
|
[deleted]
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/442tyy/when_did_women_first_start_outnumbering_men_as/
|
{
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"text": [
"Not OP, but to qualify the question:\n\nAt least in the United States, teachers at early \"public\" schools seem to have been mostly male. At the very least, this is how 19th century writers like Hawthorne depicted their 18th-century ancestors. By the mid-19th century the \"schoolmarm\" stereotype appears in contemporary fiction by authors like Mark Twain and Harriet Beecher Stowe. \n\nYet my the late 20th century, there had developed a persistant sterotype that teaching, especially in primary schools, was a \"feminine\" profession.\n\nHow and why did this gendered understanding of teaching come to be in American cultural life?",
"In [this](_URL_0_) article there is a table (Table 2) that shows the percentage of male teachers by decade (roughly). There is also a historical summary on page 4 which says it better than I can. However, here is the money quote:\n > Defining teaching as women’s work could be interpreted as a remarkably clever marketing tool used by educational reformers to meet the demand for teachers. The vacuum created by the exodus of men to the factory floor — complicated by the proliferation of new teaching positions — had to be filled by someone.",
"Just to preface this, this is not a deep response crossing multiple countries. It looks only at the case of Australia. However, Australia's education system does (apparently) have similar trends to much of the western world/other OECD countries.\n\nFirstly, this would depend on country, what type of school we're talking about (primary/elementary vs. secondary) and subject (I won't be delving into subject as it gets even more complicated, but basically stem is still male dominated, languages/arts is female in secondary). For example, within Australia (where my data is from), female primary school teachers heavily outweigh male primary school teachers with a ratio of approximately 4:1, whilst for secondary schools, the gender balance is much more equal^1 . Another thing to note from that source is that even within the same state, there was up to an 8.4% difference in the number of male primary teachers, depending on location. Taking this into account, an actual answer to this can get a bit tricky.\n\nFrom the Australian Bureau of Statistics, in 1982 there were 2.4 female primary teachers to every male, which went up to 3.8 in 2002. Now, this isn't the most helpful in determining an answer in terms of primary school teachers, but does give guidance to at least pre-1982. What interesting information is given, however, is that in 1982, there were only 0.8 female secondary teachers, meaning males still dominated in this market, and in 2002, this had raised to 1.2. Assuming the rate had changed linearly, it would be assumed gender balance occurred around 1992 for secondary teachers^2 .\n\nFrom a QLD government publication, \"In 1969, females, for the first time since 1933, constituted a majority of the teaching force, and by 1983 the percentage of females employed (60 per cent) was approaching the highest ever (61 per cent) reached between 1918 and 1920.\"^3 So, it would seem women outnumbered men around 1918-1920, however, the tables turned and men again became the majority. It took ~49 years for women to take back the majority share. Again, showing the complexity of the issue and not just a simpler \"well, in *x* year!\" This document also goes further into depth about why this happened and whatnot.\n\n\nWhilst I haven't been able to 100% answer this question, and can only provide insight into one place, I hope this is of some help.\n\n\n\n1. _URL_0_ Note: although this is for NSW, the rest of Australia has very similar statistics.\n\n2. _URL_4_\n\n3. _URL_2_\n\n\nOf possible interest: \nThis World Bank site allows you to see the percentage of female primary teachers across all countries, with data from 1981-2015 (note: some data is missing). _URL_3_ \nThere is also this UNSECO one that allows you to look at female teacher percentage from 1999 onwards across a range of different educational settings, from pre-primary to tertiary. _URL_1_"
]
}
|
[] |
[] |
[
[],
[
"http://ceep.indiana.edu/projects/PDF/PB_V6N4_Winter_2008_EPB.pdf"
],
[
"https://www.det.nsw.edu.au/media/downloads/about-us/statistics-and-research/key-statistics-and-reports/staff-information/male-school-teachers.pdf",
"http://data.uis.unesco.org/index.aspx?queryid=178",
"http://education.qld.gov.au/library/docs/edhistory/female/female-1940.pdf",
"http://data.worldbank.org/indicator/SE.PRM.TCHR.FE.ZS",
"http://www.abs.gov.au/Ausstats/[email protected]/7d12b0f6763c78caca257061001cc588/459c3882fad473a2ca2570eb0083be84!OpenDocument"
]
] |
|
30nks0
|
why is toronto the only canadian city with sports teams in the mlb and nba?
|
Is the city considered more American?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/30nks0/eli5why_is_toronto_the_only_canadian_city_with/
|
{
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"Toronto is the biggest city in Canada. Big cities tend to have more diverse tastes and larger markets, so there are more people interested in American sports.\n\nAlso, it's on the Great Lakes, so it's very close to a number of major US cities.",
"Vancouver had an NBA team (the Grizzlies) but they didn't do so well. And Montreal had an MLB Team (Expos) but again, they didn't do well. Both teams ended up moving to the U.S. ",
"Other teams have been successful in Canada, but not in the long run. There's more money in the States. Montreal Expos in MLB and Vancouver Grizzlies in the NBA come to mind. Both teams were relocated to the States."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
2sj2g6
|
what do boy/girl scout actually do?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2sj2g6/eli5_what_do_boygirl_scout_actually_do/
|
{
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"text": [
"In norway we try to have fun. Light fires, Cook Food on fire, build stuff with lumber. Also do some camoing,m in cabins, tents, under tarp or under gods sky.",
"we are just finishing up a 5 year run in Cub Scouts (ie, the junior level of Boy Scouts). They go camping. They earn merit badges and pins for all sorts of activities - cooking, science, photography, woodworking, and 100s of other things. They do field trips. They do community activities like food drives, picking up trash on the roads, etc. They do activities like Pinewood Derby (build a wooden race car and race against other boys).\n\nIt's basically a mix of fun social activities and character building activities and practical skill learning.",
"Eagle Scout here. \n\nAt the first few levels, the Scout learns the basics of surviving in the woods, making fire, and getting skills in self-discipline and motivation. At First class, the Scout begins learning about leadership skills and what it takes to run a group of peers and get them to do things together. \n\nStar is the step beyond first class, here, the Scout has shown his ability to lead a group for at least 6 months and has been in charge of some part of the troop. A good troop will be led entirely by Scouts 1st class and above with minimal input from adults whenever it's safe/legal to do so. \n\nLife comes after Star. If a Star scout is a great scout, a Life Scout is a Scout for life. He know leadership and can lead others when necessary. He embodies the ways of scouting and cheerfully serves his troop, his nation, and his communities. He is also halfway to being an Eagle Scout. \n\nThe Eagle Scout is a Scout who has taken the lessons from the other (not lower, other) ranks of scouting and pulled them together. He embodies all that Scouting is intended to build in young men. He is one of the less than 5% who make the cut and excel in the program. His stature is not given by the troop like all other ranks, it is awarded at the Council level which is the largest scouting body within each state typically. He has completed over a dozen required merit badges and perhaps twice as many elective ones. For all intents and purposes, he has received a college degree in Scouting and leadership. \n\nMerit badges are similar to courses or modules. Each one has a set of requirements for the Scout to show he has attempted and completed to the best of his ability (the merit of his work, not the quality earns the badge). There are numerous badges in a variety of disciplines that Scouts can attempt. Film, fishing, Hiking, camping, Art, Nuclear SCience, etc. Each one is different, but each lets the scout explore his interests. \n\nThere is also the Order of the Arrow (WWW, my brothers) which is an honor society for Scouts. It is fairly unique in that it is the only honor organization where non-members vote in members. Each Scout in the troop 1st class and above is eligible if he meets the requirements and is elected by the troop. The Order of the Arrow is a different topic though and not as widely known as the BSA, so I'll not digress further. \n\nThe camping aspect is generally only a portion of the time in the scouts. Perhaps 2-3 times a season a troop will go on a large trip. Patrols will typically go on a single night adventure once a month, and the entire troop will often go to camp for a week or more. The most lauded trip though is to Philmont Scout Ranch (Never got to go, want a son or Ventures daughter who will go with me). \n\nTypically, a scout troop meets once a week in their chartered organization. The troop will have a program that varies widely but typically involves some sort of news/updates/reminders, perhaps a lesson for the SCouts working on a merit badge will occur, and their will be a game for the Scouts who aren't taking a badge or working on requirements. Typically though, everyone does something during the meeting. Early ranks are taught by later ranks (Life scouts teach tenderfoots how to tie a square-hitch, etc.) and the later ranks concentrate on getting stuff done with the adults or Eagles who are merit badge counselors. \n\nAll-in-all, it's a pretty hefty, fun program where the SCouts don't realize the life skills they are learning until they've left.\n\nTl;Dr: Learn life skills and self-improvement while trying not to burn down the woods or get ated by bears. ",
"Eagle scout and Assistant Scoutmaster here! (Eagle is Americas highest boy scout rank)\n\nFor the most part it's all about developing ourselves to be good young men and eventually adults.\n\nEverything we do is geared to be fun and worthwhile . merit badges teach skills that a boy could want to know. Earning ranks require knowing skills, public service, teaching others, being a leader and developing one's character. Out door skills are a major part of the program but family values, Faith (any religion is supoorted) and pride in one's community and country are also big.\n\nThis is my understanding of the program after 8 years of experience. There is latitude to what different troops want to do but the experience is fairly regular from boy to boy."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
684kdo
|
were anatomically modern humans from 200,000 years ago exactly the same as us, except without language and culture?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/684kdo/eli5_were_anatomically_modern_humans_from_200000/
|
{
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"They were close enough that we could bump junk with them and produce viable offspring.\n\nThere would be some differences (200,000 years is enough for SOME drift) but they would be pretty similar to us. They would be on the short side, and have a lot of injuries and scars that we don't have... but fundamentally they are us."
]
}
|
[] |
[] |
[
[]
] |
||
1fd79e
|
What were the long term effects of D-Day?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1fd79e/what_were_the_long_term_effects_of_dday/
|
{
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"If you mean going beyond the war itself you end up with decades of US soldiers being stationed in mainland Europe. Without Operation Overlord (DDay actually means the day on which a campaign starts and was not the name for the invasion of Europe) it's possible that the Soviets would have overrun a lot more of Europe than they did. \n\nSo Overlord meant that the Cold War was more stable due to both spheres of influence having control over segments of Europe where neither appeared to have one up on the other to any large degree enough to make war worth it.",
"That's a good question. Part of me wants to say that it helped keep France out of the Soviet sphere of influence, but then again, there's no telling if Germany would've surrendered with the fall of Berlin. Resistance cells would've likely risen up and pushed the remaining troops out of France, given that Germany would've been able to pull more troops out of France to stem the tide of the Russians.\n\nIt's also possible that there would be two separate states, the \"Free France\" state and the Vichy State, because said resistance cells (now turned into a formal militia) may not have been able to overtake those French troops...I'm going to just stop here because this isn't /r/HistoricalWhatIf and there's no need for further speculation. \n\nTl;dr: We will never know because of the massive impact it had in \"saving\" BeNeLux, Denmark, and Italy; there are too many variables to take into account."
]
}
|
[] |
[] |
[
[],
[]
] |
||
8z44t1
|
why can’t the panama canal just dig a deep canal and remove the locks?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8z44t1/eli5_why_cant_the_panama_canal_just_dig_a_deep/
|
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"Oceans are in constant motion. This means that they surge up and down.\n\nBecause the Pacific and Atlantic Ocean aren't connected anywhere *but* the Panama Canal, you're channeling the entire difference in wave height at any given time through the canal.\n\nWithout the locks, that means you'd mostly get a fast running channel from the Pacific to the Atlantic... that reversed from time to time to run the other way. Navigating that channel would be an enormous effort.\n\nInstead, they install locks to prevent the water from flowing unchecked from one end to the other.",
"The tides on the pacific side are pretty extreme, varying by 7 meters between extreme high and extreme low tide. The result of this would be a very large wave pushing its way down the canal, this is not ideal and would likely destroy a lot of ships\n\nPlus, you'd have to dig the canal down another 26 meters and most of the canal is built to just 12 meters deep right now. Its a massive engineering effort when they want to support ships just a couple meters deeper, adding 10 or 20 or 30 meters would take decades of construction work and billions of dollars.",
"The middle part of the canal system is 85 feet above sea level.\n\nSo you'd need to dig the rest of the canal 85 feet deeper. For about 40 miles. So that would be an enormous amount of earth and rocks to dig and move, much more than was dug to place the locks as they currently are.\n\nThat's not even the biggest issue, though. Look at the map:\n\n_URL_0_\n\nSee all that water in the middle? The canal isn't a single cut across Panama, it's two canals, with locks, with **a huge ass lake in the middle**. Gatun Lake *is* the canal's middle, you enter the lake at one end and scoot across. Leveling the canal would be draining the entire lake (which itself was filled to create the canal) and drastically changing everything in the area, which now has created a large healthy rainforest area. That lake is the source of drinking water for Panama City.\n\nWeirdest part is, the mean sea level at the Pacific side is 20 feet higher than the Atlantic side owing to differences in tides. I have no idea what would happen exactly if you were to make a singe level clean cut across Panama but I wouldn't want to be standing in the middle of it when the Pacific Ocean decides it's time to be 20 feet higher than the water on the other end.",
"Because when it was built they took the easy route and had a big part or the channel go through a lake that was already there.\n\nIf they dug through land all the way without locks, it would triple the length and add extra 30-something meters of depth. That would probably be an impossible task 100 years ago(might even still be impossible)"
]
}
|
[] |
[] |
[
[],
[],
[
"https://en.wikipedia.org/wiki/Panama_Canal#/media/File:Panama_Canal_Map_EN.png"
],
[]
] |
||
6d24vd
|
as diseases like polio are eradicated why do we still need to vaccinate against them.
|
Note: I'm not an antivaxer troll. I had my kids blasted with vaccines Yosemite Sam style. Pew pew
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6d24vd/eli5_as_diseases_like_polio_are_eradicated_why_do/
|
{
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"text": [
"When a disease is considered eradicated, it is saying that we (\"we being whatever group(s) keeps these records) haven't heard of any recorded cases in ___ number of years. It's possible the disease is still out there and it's just not being reported. Vaccinations continue for a little while just in case.",
"The main reason is that the diseases we vaccinate against have not been eradicated. For example, while the incidence of polio has reduced by 99% since we began vaccination programs, there are still about 50 confirmed cases per year. While extremely unlikely, there is still a small chance that someone can be infected. If I remember correctly, smallpox is the only disease that has been 100% successfully eradicated through vaccination, with no reported cases since 1980. Which is why kids are often no longer vaccinated against smallpox.",
"also, in many less developed nations, they either don't have certain vaccines or they're not as accessible. so while something may be eradicated in the usa or europe, maybe a poor or underdeveloped nation is more common. ",
"Vaccines aren't perfect. Say a vaccine has an 85% effective rate. That means there's still 15% of people that are going to get that disease (people will still carry the disease, but it won't effect them). Well, since everyone around them has that vaccine, the disease doesn't have anywhere to go, so it burns out. \n\nNow, if there's a bunch of people that DIDN'T get vaccinated, then there's a higher chance of it spreading to those who did, and causing an outbreak.\n\nI know this isn't exactly what you asked, but I feel like it's a solid answer.",
"Many diseases that we vaccinate against are difficult to get rid of completely, because they can be carried by animals. Even if we vaccinate every human, the virus still could be kept alive in bat populations for example, and then passed back to humans if we stop vaccinating. \n\nSome viruses do only affect humans and are much easier to eradicate. Smallpox, for one. HPV for another, but a lot of people refuse that one because they can't stand the thought that their kids might have sex some day, so cervical cancer will linger far longer than it should even though we could conceivably eradicate it within a generation. ",
"Polio isn't eradicated, but we've mostly stopped vaccinating for it because it's extremely rare outside of a very few areas (a bit of Pakistan and a bit of Africa, iirc).\n\nSmallpox is eradicated, and we no longer vaccinate for that at all.\n\nOther diseases, the vaccine isn't perfect protection, or the disease has non-human reservoirs that make re-occurrence a risk forever."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
] |
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