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fbpdrm
|
why is japanese media so violent?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/fbpdrm/eli5why_is_japanese_media_so_violent/
|
{
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"text": [
"Can't speak to the media. But their history is absolutely rife with war and being a rather aggressive neighbor."
]
}
|
[] |
[] |
[
[]
] |
||
35ct7o
|
if you're standing at the south pole, can you only go north with your first step?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/35ct7o/eli5_if_youre_standing_at_the_south_pole_can_you/
|
{
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"cr37e9n"
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"score": [
3
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"text": [
"Yes. In any polar coordinate system a unit move from either pole can only go in 1 direction. After that, you can turn east or west, but the first is always North in your example."
]
}
|
[] |
[] |
[
[]
] |
||
30871y
|
what function do the mesh over the speaker?
|
Is it just for protection or something more?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/30871y/eli5_what_function_do_the_mesh_over_the_speaker/
|
{
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"text": [
"It stops foreign objects from passing through and damaging the speaker. Some are water resistant to an extent and some can help with sound quality by allowing soundwaves to pass freely through them.",
"Protection. It's so you don't puncture the material in the middle that vibrates to produce the sound.",
"Generally protection. Allegedly there can be sonic reasons but that may be the usual audiophile snake oil nonsense.",
"It's for protection and has been since at least the 1930s.",
"Audio engineer here.\nOnly protection and/or aesthetics.\nNothing to do with sound quality.\n"
]
}
|
[] |
[] |
[
[],
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|
32klbh
|
Are there any primary sources written by Jews who immigrated to the US during/after the Holocaust/Third Reich?
|
I'm having trouble locating sources that are in English - I can read German, but not Yiddish or Polish. Perhaps some of you kind folks know where I can start?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/32klbh/are_there_any_primary_sources_written_by_jews_who/
|
{
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"text": [
"Try Ruth Kluger's autobiography *Still Alive*--also available in German as (I believe) *Noch Leben*. She details her childhood in Vienna, her survival of the Holocaust, and her emigration to the United States.",
"Try Night by Elie Weisel. It is an autobiography about his survival during the Holocaust. It is a sad and touching story. I believe there is also a sequel titled Day about his transition to normalcy after the Holocaust. I am sure there are many more sources about him as well I know he did an interview on Oprah one time."
]
}
|
[] |
[] |
[
[],
[]
] |
|
2k3ble
|
what was the incentive behind the terrorist attack in canada?
|
Sorry im a bit out of the loop. From the UK, been away for the week and come back to this news. Do they know who did the shooting and why?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2k3ble/eli5_what_was_the_incentive_behind_the_terrorist/
|
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"An Islamic extremist was the shooter. The motive was to create terror in a peaceful society because Islam is at war with that society.",
"Its a terroristic act, they're just trying to cause unrest and fear in a society. ",
"I have no idea why this thread is being down voted."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
367frd
|
what advantage can a revolver give over a pistol?
|
Why some people keep using revolvers if a pistol has more bullets to shoot? It's just a matter of fashion?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/367frd/eli5_what_advantage_can_a_revolver_give_over_a/
|
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"text": [
"I assume you mean a self-loading pistol (like a common semi-auto Glock.)\n\nOne advantage is that semi-auto weapons can be prone to jamming, whereas revolvers don't necessarily have that issue in the same way. There are many more working parts in a semi-auto than a revolver, so fewer parts to break / wear out. And because of the design, you can have a wider variety of calibers in a revolver. I've seen a revolver chambered in .357 Magnum, .45-70 Gov't, .410 bore, and many more. I haven't seen a semi-auto in those calibers.",
"Revolvers have a much simpler mechanism, and a semi-automatic is more likely to jam than a revolver.\n\nBeyond that, it's really a matter of personal preference.",
"If you have limited grip strength (like me), chambering a round in a pistol, or loading a magazine with ammo, can be difficult. Revolvers are also pretty much idiotproof, which if you're not at the range very often can be useful.",
"There is a lot less to think about. A cylinder, a hammer, a barrel, and a trigger, plus the trigger mechanism/spinning mechanism. Semi autos have gas systems to clean and more moving parts in general. This is not to say that either variation is more reliable, both should be perfectly fine if kept clean, used responsibly, and well oiled.\n\nA side note is that because of their reliance on mechanical cylinder rotation, revolvers are able to fire ammunition that has more powder (magnum ammo like the .357 or. 44). Semi autos use a gas system to chamber the next round and the high pressure from such powerful ammo unless it is built larger, and doing this defeats the purpose of having a small gun. A Desert Eagle is a great example of a oversized semi auto, and comes in .357, .44 as well as it's more famous .50 AE. ",
"A revolver is (arguably) more reliable because the cartridges (bullet + case) just sit in the cylinder as it rotates from shot to shot.\n \nIn a pistol with a stack of cartridges in a magazine, each cartridge has to be moved from the top of the mag. stack and completely into the chamber or the gun won't fire. After it is fired, the casing (usually brass) has to be ejected before the next cartridge can be chambered. There can be jams with both operations but they are almost always quick to fix. (could be fatally not quick enough if you **really** needed the gun to go boom ...)\n\nI have only had 1 failure with a revolver and it was due to the factory made ammunition - the bullet only traveled a fraction of an inch and stopped partially in the barrel and partially in the chamber. This is not a quick fix - you have to get a rod and tap the bullet back down so the cylinder can swing out. This can also happen in a pistol too.\n\nIt takes more skill to quickly reload a revolver, even using a device called a speedloader which holds a number of cartridges in the same pattern as the cylinder. \n\nPersonally, I would prefer a revolver in a very dusty or dirty environment. Also, when I go hiking/camping.\n\nThe military and police have largely switched over from revolvers to magazine fed pistols.",
"Revolvers give you a better chance of surviving Russian roulette. You can also visually verify rounds remaining in most revolvers, but please don't point the barrel at yourself to do so. \nRevolvers also don't have issues feeding low-power rounds.",
"One advantage that I have not seen mentioned yet in the thread is that a revolver is more practical if you do not want to leave the cartridge casings on the ground. \n\nFor pistols, firing a shot will expel the casings automatically and it can be a hassle to collect them. A revolver keeps the casings in the cylinder after firing."
]
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|
3dhgd2
|
when a television receives no signal, why does it output that "salt and pepper" screen?
|
[Link](_URL_0_) for those who don't know what I'm referring to.
What causes it? Why is it black and white? Why that particular "pssh" sound?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3dhgd2/eli5_when_a_television_receives_no_signal_why/
|
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"Interference it is picking up background radiation, cosmic rays and other signals which it is attempting to sort out into a picture and failing, because there is no signal.",
"This refers to obsolete analog TV, not digital. \nMost of the noise you see and hear comes from the radio signal amplifiers in the TV. All amplifiers produce electronic noise. The more they amplify, the greater the noise. Tuners are designed to be able to pick up very strong and very weak signals, and they adjust the amplifiers automatically to give you a stable picture and sound. The weak signals need amplification by around one million times. With no signal, all you see is the noise. You can see the same type of noise on a weak signal. \n\nIt is black and white because TVs blank out color information when no color signal is received. The circuit is called the color killer. Newer TVs blank out all picture and sound when there's no signal. \n\nThe sound gives you the \"pssh\" sound for the same reason as the picture. FM radios can give you the same noise, unless they have a muting circuit (like the color killer). \n\nBTW the TV signal uses AM and the sound is FM. In the TV transmitter I maintained, the picture and sound used separate power amplifiers and were only combined so they could share a common transmitting antenna. Some FM radios could pick up TV channel 6 sound because it was just below the FM band."
]
}
|
[] |
[
"http://i.imgur.com/6oyqOt8.gif"
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[
[],
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1mmxt4
|
If all people have the same genome, what makes us different? And does this relate to gene expression?
|
All people have the same genome (or very close to), but what makes us different from one another then?
Random SNP's? If yes - why would a changed SNP not account for new type of gene?
And how does this match up with gene expression?
(i'm sorry if i'm asking absurdely)
|
askscience
|
http://www.reddit.com/r/askscience/comments/1mmxt4/if_all_people_have_the_same_genome_what_makes_us/
|
{
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"text": [
"It might be helpful to start with a metaphor. Imagine a grocery store. This store is has all your major products such as ice cream, candy and pastries (I may have a slight sweet tooth). Different stores in the same chain are required to stock the same TYPES of products, and each store is required to have two and ONLY two brands available of each product. However, each store can vary as to which specific brands it uses to fulfill this requirement. \n\nIn this metaphor, the types of products the store sells are the **genes**. The specific brands that the store carries of each product type would be **alleles**. Just as “chocolate cake mix” does not refer to a particular brand of mix, BRCA1 does not refer to a specific allele. Instead, it describes a region of the genome that contains the elements necessary to produce a protein. What this region actually produces will depend on what alleles of BRCA1 the person has.\n\nFinally, the total information needed to run the store (the “Operating manual”) is the **genome**. This includes information as to which types of products the store sells, as well as non-product information such as store hours, shift times, etc. Just as all members of the same species should have the same list of genes and noncoding information (barring extreme events such as the loss of a chromosome), all stores in the same chain should stock identical types of products. A closely related species may have a very similar genome compliment, just as a similar type of store run by a rival chain may have a similar list of products and operating manual. The more distant the species/stores are though, the less similar their genes/manual will be. For example, a grocery store will run very differently than an electronics store, and humans have a very different genome from *E. coli*.\n\n**Genome** is different from **genetic sequence**. If the genome is the operating manual of a store, the genetic sequence is the actual text in the manual. While every store in the same chain will have the same manual (identical format, organization, etc) each individual store may have typos in their particular version of the manual that may result in interesting changes in how one store in a chain is run compared to another. Some of these typos may be minor, and result in one store stocking different brands of a type of product than another. Other typos may be severe though, and cause a store to not stock a particular product at all! If this product is really important, that given store might fail due to an error like this. Likewise, **mutations** in the genetic sequence can cause changes in the specifics of the genome if they result in new **alleles**; simple SNPs generally do not create NEW GENES!\n\nTo move to a biologic example, you may have a **gene** that produces a protein that gives a flower a particular color. If the flower is diploid, it will have two copies of each gene. If both copies of the gene produce a protein that is blue, you will get blue flowers. This blue “version” of the gene is an **allele**. However, you could have a SNP that prevents functional pigment from forming. In this case, if you have two copies of this allele you will get a flower that is white. Breeding a flower with two blue alleles with one with two white alleles would give you a hybrid that has one blue allele that makes functioning blue pigment, and one white allele that produces no pigment. In this simplified scenario, we would expect the hybrid flower to be blue (or light blue) as it still has one functioning blue allele that masks the effect of the allele that is non-functional.\n\nThis is why two people can have identical genomes but still have many important differences between them. Sometimes this is a result of mutations generating novel alleles that give different protein products from a given gene. As other people have mentioned, this can also stem from changes in the regulation of these genes (when they are turned “off” and “on”), though these types of changes tend to have SIGNIFICANT impact, and are theorized to be an important factor in the emergence of new species.\n\nEdit: Tweaked formatting and added comparison of genome to genetic sequence"
]
}
|
[] |
[] |
[
[]
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|
4a5yl0
|
what’s the benefits of using 32-bit windows operation system over 64-bit windows operation system?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4a5yl0/eli5whats_the_benefits_of_using_32bit_windows/
|
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"text": [
"Marginally faster in older hardware. However the security benefits of 64bit are IMHO outweigh all.",
"Older hardware can be a pain to get 64-bit drivers. Also, old but still active CPUs might lack 64-bit instructions. 32-bit is slightly faster as well on dinosaurs.",
"64 bit Windows no longer supports 16-bit Windows applications. If you require some 16-bit apps, then you have to stick with Windows 32. This mostly applies to business with old custom apps they don't want to, or can't update.",
"most people are familiar with desktop video settings in windows. Like if you want 16.8 million colors, you need 24bit video to do it, and 256 colors only requires 8 bits, and 16 bits can encode 65,000 colors. \n\nThe bits in a CPU and a piece of software work in a similar fashion. The 64 bit operating systems can access huge amounts of memory without having to resort to tricks like paging and swap space. This allows a program to be very complex, but also very efficient. It can hold all of it's variables in memory at the same time without any tricks. It's like having a really big work area, with which to do your work. \n\nA 32bit operating system has a much smaller size of addressable memory and work space. This is regardless of how much ram the system has. In order to have very large working memory pools the system has to divide the memory up into pages because it can't keep track of it all at once because you can only encode so many positions with 32 bits of data. The larger the working memory space in bit width, the more it can handle at once without swapping and such. \n\nThen at the CPU level you have 32 and 64bit processors, but this is usually referring to the width of the CPU bus. The bus is like a highway that loads data into and out of the CPU. Having 64 lanes of traffic lets you move more at once than 32 lanes of traffic. The MHZ speed of the CPU is more like a speed limit. If you have 32 lanes, but the speed limit is 1000mph then you can move a good amount of cars, but a 64 lane highway can move the same amount with a 500mph speed limit, so you get more from it. You can move massive amounts of data at once the wider the path into and out of the processor. \n\nThen there are other lanes like to memory or the PCIx bus, and memory controllers, and chipset bridges etc. ",
"There really is no advantage to 32bit over 64bit beyond 16bit application support, but you'd be hard pressed to find a 16bit application out in the wild anymore. \n\nWe've also reached a point where even low end PCs on the market have more RAM than a 32bit OS can address."
]
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[],
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||
e4t54c
|
why do screens shown on television (like the scoreboard of a football game) appear to constantly flash on the television but not with the naked eye?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/e4t54c/eli5_why_do_screens_shown_on_television_like_the/
|
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"text": [
"These screens are made up of LEDs. The LEDs each require a driver circuit to make them light up. But to save costs, many LEDs share the same driver circuit. But since the driver can only drive one LED at a time, the driver quickly switches between LEDs. This happens way too fast for us to see at normal speed. However when they show a slow motion replay on TV we can now see the flashing as the driver circuits switch which Leads they are driving.",
"What you see on a screen is not fluid movement, but a series of static images. The screen will show one image, then replace that with another image.\n\nWhen a screen is being recorded by a camera, the camera is also taking a series of images. If the two sets sync up right (or wrong), some of the images that the camera records will be \"in between\" the images being shown on the screen (either dimmer, blurry or black depending on variables such as make and model).\n\nBecause of that variation, the final image you see will not be consistant, resulting in that on/off flash or flicker.",
"The screens don't display an image constantly they refresh many times a second. Think of the flip books kids make that have a stick figure in a slightly different picture on each page. When flipped more quickly the motion looks more fluid. Screens work similarly. They repaint the image over and over. \n\n cameras similarly have a rate at which they capture images. The camera rate and the screen refresh rate aren't the in sync with each other so you see periods where the screen is dark or only partly painted in. That causes the flicker. \n\nYou might have seen similar phenomenon when a strobe light is illuminating a moving person and they appear to move in a jerky interrupted fashion. You're only seeing some of the motion and missing other parts. \n\nTo the human eye around 24-30 images per second looks fluid and seamless. Though with more rapid motion being captured and different screen technolgies in use, you'll see TV screens refreshing more and more rapidly to keep things looking fluid and smooth. 60-480 times per second have been common. \n\nThere are more variables at play but I hope this helps."
]
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|
[] |
[] |
[
[],
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|
43ezh6
|
if our bodies can adapt to fight infections, why do we always contract colds?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/43ezh6/eli5_if_our_bodies_can_adapt_to_fight_infections/
|
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"As well as viruses mutating. Antibodies only have an effect for so long. If you're sick and then you recover but your family gets sick from being in contact with you, chances are you won't get that sickness back. You stop being sick because antibodies identify what's making you sick and helps remove it. When your family is sick with your cold, the virus is still in the air but the antibodies in your system stop it from doing any damage. When everyone is okay and the air is purified by time, the antibodies kinda fizzle away/die/sleep however you wanna look at it.\n\nIf it snows, you go out and shovel. You don't keep shovelling in the summer so you put the shovel away. When it snows again the next winter, you pull out the shovel and start again.\n\n If you get a cold again, they have to reset and start over again. That's why you should get your flu shot every year, they insert a very small portion of dead influenza cells. Your body detects it, creates a protection and so that if the influenza cells come to you, they can't affect you."
]
}
|
[] |
[] |
[
[]
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||
ezvonv
|
My Highschool Teacher Has Been Giving Us Historically Incorrect Information. Is my information historically accurate?
|
At my high school, government is a required class for graduation and I'm taking it this semester. (The government teacher is also in charge of teaching US History, World History, and Civics) This year our school got a new government teacher and for the purposes of this post, I will say that she has been less than satisfactory at her job so far. We are currently doing a unit about diplomacy and we have been assigned historical empires to act as diplomats for. Recently I noticed that a lot of the information that she's been giving my class is incorrect. I am presenting this information to her higher up and want to make sure my argument is factually correct and well thought out so I wanted to ask for this subreddit's help.
I will list everything that she misinformed us about in chronological order:
1. We were told to make a presentation about the empire that our groups were assigned and she gave us fact sheets with information about our empires on them. My group had the British Empire. Our fact sheet said that the British Empire was Catholic, and to be fair, they were Catholic for a period of time, but the informational sheet made no mention of Protestantism.
1. I figured that this must have just been a simple mistake on her part and gave her the benefit of the doubt in that instance.
2. The next class we (the entire class this time and not only my group) analyzed the letter of Queen Elizabeth's ex-communication from the Catholic church. My teacher told the class that Queen Elizabeth was Catholic and proceeded to misinterpret the letter.
3. That same class, she made a power hierarchy of the British Empire at that time on the whiteboard of the classroom. Her hierarchy (from top to bottom) was God, The Apostles, The Pope, The King/Queen, nobles, and then peasants. Here are the issues that I have with this:
1. The mixture of religious figures and actual people. God and The Apostles shouldn't belong on a political power hierarchy, especially in a public school like mine. I understand that religion was a large piece of the British Empire but having God on that list insinuates that God is a historical figure that definitively exists. While I respect other people's belief in God, teaching God's existence at a public school is not a separation of State and Church (I live in the USA).
2. The actual power hierarchy was different and more complicated than the one she presented us with, especially at the time of the Pope's ex-communication of Queen Elizabeth
Is there anything that I missed or got incorrect?
TL;dr : Teacher tells students that the British Empire was Catholic and that Queen Elizabeth was also Catholic. Spends entire class misinterpreting the Pope's letter of ex-communication of Queen Elizabeth. Insinuates the definitive existence of God and The Apostles and includes them on a list of political power.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/ezvonv/my_highschool_teacher_has_been_giving_us/
|
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"TL;DR: Elizabeth I was Protestant. The English Empire, as much as an empire can be a religion, was Protestant also. The Pope excommunicated Elizabeth for being Protestant. Your teacher’s interpretation is wrong.\n\nFirst of all, it seems your teacher is confusing the British Empire with the English Empire. The British Empire cannot technically be said to have existed before the Acts of Union in 1707, more than a century after the death of Elizabeth I. Before this time, the Kingdom of Great Britain did not exist. Elizabeth was queen of England. She did not even rule the entire island of Great Britain; Scotland was a separate, independent country with its own king and parliament until the Scottish king James VI became king of England (as James I) on Elizabeth’s death in 1603. Even then, the two kingdoms remained legally separate countries until they were unified in 1707. So, if your assignment is about the British Empire specifically, then Elizabeth I’s personal religion and religious policy are irrelevant.\n\nBut, one could argue that that is simply a semantic difference. As for whether either of these empires were Catholic or not, ever since the Act of Settlement in 1701 it has been illegal for the monarch to be Catholic. You can read the law, still in effect today, [here](_URL_1_). The relevant section includes this text:\n\n > And it was thereby further enacted That all and every Person and Persons that then were or afterwards should be reconciled to or shall hold Communion with the See or Church of Rome or should professe the Popish Religion should be excluded and are by that Act made for ever incapable to inherit possess or enjoy the Crown and Government of this Realm and Ireland and the Dominions thereunto belonging or any part of the same or to have use or exercise any regall Power Authority or Jurisdiction within the same.\n\nInstead, it was enacted\n\n > That whosoever shall hereafter come to the Possession of this Crown shall joyn in Communion with the Church of England as by Law established.\n\nThe monarch is required by law to be a member of the Church of England, which is a Protestant Church.\n\nLegislation was not limited merely to restrictions on who could ascend to the throne, though. Going back more than 150 years before the Act of Settlement, a series of “Acts of Uniformity,” passed between 1549 and 1663 established that the rites and practices of the Church of England were the only legal religious practices in England (later Great Britain and, later still, the United Kingdom). Most notably, they required the use of the Book of Common Prayer, which is a fundamentally Protestant text. \n\nAll public employees, including Members of Parliament, were required under the Acts of Supremacy to take an oath affirming that the monarch was the supreme authority in all matters, including spiritual. The text used in Elizabeth I’s reign was as follows:\n\n > I, ______, do utterly testify and declare in my conscience, that the Queen’s Highness is the only Supreme Governor of this realm, and of all other her Highness’s dominions and countries, as well in all spiritual or ecclesiastical things or causes, as temporal, and that no foreign prince, person, prelate, state or potentate has, or ought to have, any jurisdiction, power, superiority, pre-eminence or authority ecclesiastical or spiritual, within this realm; and therefore I do utterly renounce and forsake all foreign jurisdictions, powers, superiorities and authorities, and do promise that from henceforth I shall bear faith and true allegiance to the Queen’s Highness, her heirs and lawful successors, and to my power shall assist and defend all jurisdictions, pre-eminences, privileges and authorities granted or belonging to the Queen’s Highness, her heirs and successors, or united and annexed to the imperial crown of this realm. So help me God, and by the contents of this book. [*Source*](_URL_2_)\n\nFurthermore, under the Corporation Act of 1661, all public officials were required to take communion under the auspices of the Church of England. Soon afterwards, the Test Act of 1673 required them to explicitly deny that transubstantiation (a central piece of Catholic theology) took place.\n\nOk, so that establishes the official religious practice of the late English Empire and the early British Empire. The requirement to take the Oath Supremacy to Elizabeth demonstrates her Protestantism. And to address your teacher’s last point, the Papal bull [*Regnans in Excelsis*](_URL_0_), which formally excommunicated Elizabeth in 1570, states that\n\n > Elizabeth, the pretended queen of England and the servant of crime, has assisted in this, with whom as in a sanctuary the most pernicious of all have found refuge. This very woman, having seized the crown and monstrously usurped the place of supreme head of the Church in all England to gather with the chief authority and jurisdiction belonging to it, has once again reduced this same kingdom- which had already been restored to the Catholic faith and to good fruits- to a miserable ruin.\n\nAnd\n\n > Therefore, resting upon the authority of Him whose pleasure it was to place us (though unequal to such a burden) upon this supreme justice-seat, we do out of the fullness of our apostolic power declare the foresaid Elizabeth to be a heretic and favourer of heretics, and her adherents in the matters aforesaid to have incurred the sentence of excommunication and to be cut off from the unity of the body of Christ.\n\nI’m not sure how this could be interpreted as Elizabeth being a good Catholic. The Pope has literally declared that she is a heretic. She is excommunicated, which means that she is not a member of the Catholic Church. That is literally what excommunication means.\n\nFinally, what should you do next as a student? As a high school history teacher myself, I would suggest first of all that you speak with your teacher privately. You say that she is a new teacher who is teaching four different classes. That puts a lot of pressure on a teacher, and it seems that the English Reformation isn’t exactly her specialty. I suggest that you not confront her publicly (i.e., in front of the entire class). See what she says and go from there. If you are truly concerned afterwards that you will continue to get poor instruction, or that you will not be graded fairly, then reach out (respectfully) to your school administration. You’re correct that her hierarchy that includes religious figures seems inappropriate, though without knowing more context I hesitate to pass judgement. I could imagine a totally legitimate, though somewhat flawed, lesson using something like that to explain how people in the early modern period themselves saw the power structure. So anyway, talk to her, lay out your evidence, see what she says, and then decide whether to escalate the matter."
]
}
|
[] |
[] |
[
[
"https://www.papalencyclicals.net/Pius05/p5regnans.htm",
"http://www.legislation.gov.uk/aep/Will3/12-13/2/contents",
"https://books.google.com/books?id=UGi6WWtzkJYC&pg=PA323&lpg=PA323&dq=do+utterly+testify+and+declare+in+my+conscience+that+the+Queen%27s+Highness+is+the+only+supreme+governor+of+this+realm,+and+of+all+other+her+Highness%27s+dominions+and+countries&source=bl&ots=LGBy5Gu7w1&sig=ACfU3U1ooxHfHmgMlOKucO7kzl3q7sEjIQ&hl=en&sa=X&ved=2ahUKEwjUz92n4L3nAhVIZ80KHeihDd0Q6AEwDnoECAgQAQ#v=onepage&q=do%20utterly%20testify%20and%20declare%20in%20my%20conscience%20that%20the%20Queen's%20Highness%20is%20the%20only%20supreme%20governor%20of%20this%20realm%2C%20and%20of%20all%20other%20her%20Highness's%20dominions%20and%20countries&f=false"
]
] |
|
748i3w
|
does peeing directly into the water or on the side of the bowl keep your toilet cleaner?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/748i3w/eli5_does_peeing_directly_into_the_water_or_on/
|
{
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"dnwaa43",
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5
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"text": [
"Side of the bowl. \n\nThe water hits it at an angle and bounces downward towards the water. \n\nWhen hitting the water it’s forced upwards. \n\nAdditionally, forget the cleaning issue. Hitting the water is disgusting, loud and horrible for anyone else within a city block to have to listen to. ",
"Side of the bowl gets rid of big splashes but you'll get a fine mist. in the water makes big droplets but i think you get somewhat less mist?\n\nsit when you pee at home and you basically don't need to worry about splash zones."
]
}
|
[] |
[] |
[
[],
[]
] |
||
20f0pt
|
how are fire drills done in skyscrapers?
|
Just had a fire drill at work and we walked down 4 floors worth of stairs. So how do they do it in buildings with 50 or even 100+ floors?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/20f0pt/eli5_how_are_fire_drills_done_in_skyscrapers/
|
{
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"Our building just had a supervisor come up and demand a few people meet in the hallway at the elevators.\n\nHe described how to use the emergency stairs and phones, what not to do, how the elevators wouldn't be working, and that was it.\n\nWe are on the 15th floor of an 18 floor building.\n\nI don't know if thats universal, but I think in general they just test alarms, remind everyone of the basics steps for evacuation, and thats it.",
"This is somewhat speculation but i did recently read about 2,000 pages worth of NIST reports regarding the 9/11 attacks on the WTC.\n\nThere seemed to be a few factors to take into consideration.\n\n1. Identify the severity of the fire.\n\n A microwave fire on floor 59/120 may not be worth evacuating the entire building mainly because it *may* cause more harm than good if you have to move 30,000 people out of a building and fire fighters can't get in.\n\n2. Most buildings are designed with reduntant stairways in case of a fire (usually less fancy but still functional)\n\n3. Most skyscraper fires are fully beatable and can be contained, many people in this thread may draw their eyes back to 9/11 but that was a VERY VERY rare case in which the kinetic energy from the plane structurally compromsied the building and the fuel from the plane managed to spread between floors and ignite many fires.\n\nIn most skyscraper fires, tenants that are trapped will be able to wait until they are either overcome by smoke, burned to death or rescued by firefighters.\n\nAnd the newer a building is the better it's designed for prevent the smoke or fire death part.\n\n(i just realised you said fire *drill*, but whatever)"
]
}
|
[] |
[] |
[
[],
[]
] |
|
6db8du
|
why do carbohydrates and proteins contain 3 kcal/gram and fats contain 9 kcal/gram if they have the exact same mass but different structures?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6db8du/eli5_why_do_carbohydrates_and_proteins_contain_3/
|
{
"a_id": [
"di19jkx"
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"score": [
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"text": [
"Calories are a measurement of how much energy our body can create from these substances. Carbohydrates are less energy efficient gram for gram than fat. Also it's 4 kcal/g not 3."
]
}
|
[] |
[] |
[
[]
] |
|
t6u3d
|
modular synthesizers
|
I mean [these](_URL_0_)
I know basic synthesis like FM, additive etc. where you turn knobs to set waveforms and filters and stuff.
What's the big difference to modular synthesizers? Why are they so huge with all those chords etc.? Are they something like "open synthesizers" where you have to wire everything yourself or do they work completely different? Some special functions/possibilities compared to other synths? If no, what's the appeal to them?
not sure if this would be more appropriate in /r/edmproduction or something. I though the question was a bit to general to ask it there, and well, you guys don't have a specific theme or something on here so it's probably allright :)
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/t6u3d/eli5_modular_synthesizers/
|
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"OHHHH\n\nWhen these huge synths came around, the technology to make them was very rough. \n\nMost of these synths could only produce one note at a time, and the sounds where created by an oscillator. This oscillator defined the basic tone for the sound, a sine wave oscillator sounds like a flute, triangle waves more like a oboe etc. \nTheses oscillators by their own, are quite boring, so to spice things up, the sounds needed to be tinker with, that's why you see all those cables. The oscillator was patched through filters that taylor the sound, filters like resonance, high pass filters, vibrato and more.\n\nSo the musician plays a key on the keyboard, the higher the note the higher the voltage (depending on the maker of the keyboard), the oscillator generates the sound depending on this voltage and then the sound is sent to through these cables to these filters to create this amazing sounds you hear form vintage synths.\n\nThese devices then evolved to be digitally controlled and FM, essentially making all these cables disappear inside a self contained box and the computer makes the route you decide for the sound.\n\nToday you can have digitally controlled analog synths, wavetable synths, physical modeling, granular synth and a lot more.\n\n\nEDIT:\nAlso:\n\nWhen you see old Genesis or Pink FLoyd or Tangerine Dream videos, you see the have a bunch of these synths... why you may ask, well, simple:\n\nTo make these sounds, you needed to spend a bunch of time patching and recalling all the settings that you want and took note in a folder, but changing them was not easy and took time, so you had 6 synths, one for each sound you wanted, and sometimes a roadie or synth tech comes and starts to change a keyboard for the next song.\n\nAlso note: Not every keyboard was monophonic (a single note at a time), polyphonic keyboards started to appear but only 2 o 3 o 5 notes per keyboard, depending on the year.\n\nAlso the Melotron: this beast was amazing. Basically you had a keyboard that was polyphonic and had samples of real intruments!!!! How? there were tape heads and loops of tape with this recordings on the back of the device. It's sound is so amazing but transporting and calibrating and maintaining it was a tough feat.",
"You understand additive synthesis - you know that you have envelope generators, oscillators, LFOs, filters & whatnot. In a \"normal\" analogue synth, all of these are pre-wired so that there's a limited number of ways they can interact. A modular synth, OTOH, is like a bunch of legos that lets you string the bits together in any way you want - even crazy ways that don't make sense.\n\nPart of the reason they're so big is because, using the old technology of the original synths, they actually *had to be big*. Part of it is that, they need to be big enough to handle and see without getting lost.",
"I'm too lazy to read the long and probably correct answer from f3rn4ndrum5, so i'll just answer anyway with a quick easy answer, because 5 year olds don't like long answers. =P\n\nA modular synthesizer is a synth with the capability to add more modulators using patch cables. If you've ever used the DAW called Reason, the Thor synthesizer is an excellent example of a modular synth. \n\nThink less keyboard and more rack-mounted gear.\n\nThe basic appeal to the modular synth was it's workability/flexibility regarding shaping your sound to the exact parameters you want.\n\nHope that helps =)"
]
}
|
[] |
[
"http://farm4.static.flickr.com/3057/2682162358_81ddda1054.jpg"
] |
[
[],
[],
[]
] |
|
9kl4qj
|
How do you calculate the average sum of dice rolls when a "drop the lowest roll" mechanic is used?
|
In various tabletop role-playing games, game designers will often use a system to set character statistics that is some derivation of "roll an x-sided die y-times, drop the lowest z rolls, and sum up the results." The most common example of this is rolling a 6-sided dice 4 times and dropping the lowest result.
Now, calculating the average sum of 3 six-sided dice rolls is simple and intuitive, yielding a result of 10.5, but when adding a 4th and dropping the lowest result, the average comes out to a (seemingly) strange irrational number of ~12.22. There are other derivations of this problem that yield other seemingly random irrational values, and while I can get to the result by writing out all the combinations and summing up the probabilities, is there a way to write this problem out algebraically?
|
askscience
|
https://www.reddit.com/r/askscience/comments/9kl4qj/how_do_you_calculate_the_average_sum_of_dice/
|
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"Suppose we roll a die *N* times and label the results as X*_1_*, X*_2_*, ..., X*_N_* and let *M* denote the minimum roll. Then the sum of the best N-1 rolls is\n\n > S = X*_1_* + X*_2_* + .... + X*_N_* - M\n\nExpectation is linear and all of the X*_j_*'s have expected value (d+1)/2 where d is the number of sides of the die. (This assumes that the values of the die are 1, 2, 3, ...., d.) So then the expected value of the best N-1 rolls is\n\n > E(S) = N(d+1)/2 - E(M)\n\nIt's then just a matter of finding the expected value of the minimum. For a random variable with a continuous probability density, this is a standard exercise and not too difficult. For a probability density that is not continuous, the calculation is bit more subtle.\n\nYou can do this via \"brute force\" by considering the possible values of M and with what probabilities they occur. For instance:\n\n* M = 1 unless all rolls are ≥ 2. The probability of this occurring is 1 - ((d-1)/d)^(N) = (d^(N) - (d-1)^(N))/d^(N).\n* M = 2 if all rolls are ≥ 2 but not all are ≥ 3. The probability of this occurring is ((d-1)^(N) - (d-2)^(N))/d^(N).\n* M = 3 if all rolls are ≥ 3 but not all are ≥ 4. The probability of this occurring is ((d-2)^(N) - (d-3)^(N))/d^(N).\n* ... and so on.\n\nThen you can calculate the expected value of *M* by summing m*_j_*P(M = m*_j_*) over *j*.\n\n > d^(N)E(M) = 1\\*[d^(N) - (d-1)^(N)] + 2\\*[(d-1)^(N) - (d-2)^(N)] + 3\\*[(d-2)^(N) - (d-3)^(N)] + ... + d[1^(N) - 0^(N)]\n\nThe sum on the right simplifies quite a lot and we end up with:\n\n > E(M) = (1^(N) + 2^(N) + 3^(N) + ... + d^(N))/d^(N)\n\nSo putting this all together we find the following result. If we roll *N* fair *d*-sided dice with face values 1, 2, ..., d, then the expected value of the sum of the rolls with the lowest roll dropped is....\n\n > E(S) = N(d+1)/2 - (1^(N) + 2^(N) + 3^(N) + ... + d^(N))/d^(N)\n\nFor N = 4 and d = 6 (rolling a 6-sided die 4 times and keeping the best 3 rolls), we get\n\n > E(S) = 15869/1296 = 12.2446\n\n**Alternative method:** You can also use the result that if X is a random variable that takes on only non-negative integer values, then E(X) = Σ*_j=1_*^(∞)P(X ≥ j). In this case, P(M ≥ j) = (d-j)^(N)/d^(N) for j = 0, 1, 2, ..., d; and P(M ≥ j) = 0 otherwise. So we have\n\n > E(M) = d^(N)/d^(N) + (d-1)^(N)/d^(N) + (d-2)^(N)/d^(N) + ... + 1^(N)/d^(N)\n\nand we just recover the same result as before.\n\n----\n\nAs an interesting side exercise, if these rolls were really, say, uniformly distributed on the interval [0, 1], then this calculating is much easier. For that case, the *N* rolls would, on average, all distribute themselves at equally spaced intervals in [0, 1]. So if there were only 2 rolls, they would, on average, divide the interval into [0, 1/3], [1/3, 2/3], and [2/3, 1]. So the min and max would have expected values of 1/3 and 2/3, respectively.\n\nIn general, the minimum of N rolls would have expected value 1/(N+1). The next highest roll would have expected value 2/(N+1), and so on. The maximum would have expected value N/(N+1).\n\nNow you *can* recover this result from the discrete case as a suitable limit with d -- > ∞. First, normalize the rolls to take on the *d* values 1/d, 2/d, 3/d, ..., 1. So the rolls are discrete and uniform and all have values in the interval [0, 1]. Then the expected value of M is just the same formula as above, but divided by *d*.\n\n > E(M) = (1^(N) + 2^(N) + 3^(N) + ... + d^(N))/(d^(N+1))\n\nNow take the limit of this expression as d -- > ∞. But be careful! Not only do the terms depend on *d*, so does the *number* of terms. In fact, this is just a Riemann sum which approximates the integral of f(x) = x^(N) on the interval [0, 1]. Thus as d -- > ∞, the limit is just the value of that integral, which is.... 1/(N+1). That is just the expected value of the minimum of *N* rolls for a *continuous* uniform random variable!\n",
"If in doubt consider all cases with nested sums. Well, let a computer consider all cases. For some special cases there are shorter approaches but that will always work.\n\n[_URL_0_: The sum of the highest three dice out of 4d6](https://_URL_0_/program/11d0).",
" > strange irrational number \n\nNo, it's *definitely* rational. It's 15869/1296\n\nThe easy way to do it is to recognize each roll is the sum of four d6 values minus the minimum of four d6 values, and then get the expectation of keeping the best three by taking the difference of the expectation of the sum of 4d6 and subtracting the expectation of the minimum of 4d6.\n\nWith 4d6 you can find the expected value of the minimum by recognizing that there's one way to get a 6, 2^(4)-1^(4) ways to get a 5, 3^(4)-2^(4) ways to get a 4, 4^(4)-3^(4) ways to get a 3, 5^(4)-4^(4) ways to get a 2 and 6^(4)-5^(4) ways to get a 1. Consequently the minimum of 4d6 has a mean of (1 x 6 + 15 x 5 + 65 x 4 + 175 x 3 + 369 x 2 + 671 x 1)/1296 = 2261/1296 ≈ 1.7554 and so the average of 4d6 keep the best three has an average ≈ 14 - 1.7554 = 12.2446.\n\n"
]
}
|
[] |
[] |
[
[],
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"anydice.com",
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|
4telel
|
If being a Gladiator was so intense, life expectancy was so short - why did so many people become one ?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4telel/if_being_a_gladiator_was_so_intense_life/
|
{
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"It wasn't all bad. They were celebrities. They had a place to live, a purpose in life, they received rewards (drink and women) for their performances, and they won fame and renown. If they were a slave they could win their freedom. If they were already free, they paid off their debts and might win an honourable retirement. Victorious gladiators were often prostituted to wealthy women, and while that's pretty exploitative from a modern point of view, I wouldn't be surprised if it was viewed as a perk.\n\nIt's important to note they also weren't constantly being killed, as they were prized investments. They didn't always fight other gladiators, but were often used as performers/executioners in other sorts of 'entertainment'. Even if they did fight other gladiators a lot, they could still survive many fights and when they eventually lost, could be spared.\n\nYou might similarly ask why people become professional fighters today. Unless you make it really big the pay totally sucks, the training is extremely hard, the risk of serious injury extremely high, and you accrue injuries that make your older life harder. But people still do it in droves, and many keep doing it as long as they physically can. Things like wanting to prove masculinity, wanting fame and respect and glory, sheer aggression, a lack of other desirable options or an addiction to the lifestyle are reasons now and probably have always been reasons for people to take up combat sports, even those as dangerous as gladiatorial sport."
]
}
|
[] |
[] |
[
[]
] |
||
1i6zzl
|
How much did the people of Europe during the Dark Ages know about Rome?
|
Title says it all.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1i6zzl/how_much_did_the_people_of_europe_during_the_dark/
|
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"text": [
"Related to your question, you might want to [review AskHistorian's section on why \"The Dark Ages\" is outdated as a term](_URL_0_). This means that people trying to answer the question might not be sure about what period you're describing unless you provide specific dates or more recent periodization (ie. \"Early Middle Ages\" or \"Late Antiquity\").",
"Most of Europe saw the byzantine empire as the roman empire. It wasn't until after the fourth crusade when the empire was reduced to a few holdings in greece that europe stopped seeing it as rome. In fact, the term byzantine empire is a recent creation, and the people of the early middle ages simply called it the roman empire. Charlemagne's coronation as holy roman emperor caused a great deal of conflict between the two empires, and the holy roman emperors used the term, \"empire of the romans\" while the byzantines continued to use \"roman empire\". In short, you need to stop thinking that rome fell, as the eastern half (which had for a while been the wealthier and more important part of the empire) never fell. Even in the western empire, Rome had not been the capitol for a long time when it was sacked. The capitol had been moved numerous times to places like Milan and Revanna. So the simple answer to your question is that Rome never really fell until the end of the byzantine empire (and even then the ottomans and russians claimed to be the succesors of rome).",
"And yet no one has answered the question. What did Western Europeans know about the earlier Roman Empire? Were they aware of its laws? It's language and culture? Did they feel less civilized than the earlier Romans? What did they regret? \n\nIt's worth noting that the Romans themselves had been Christians for a few hundred years, so had any later Europeans known this they might very well have felt more kinship to the Romans than you might think. \n\nIn any case, telling us that there was also a Byzantine Roman Empire in the East so that the Empire didn't really fall hardly addresses the OP's original question. There were in the West large numbers of people no longer under the authority of the western Roman Empire. What did they know of the earlier Roman Empire? And what did they think about it? ",
"If the question pertains to what European (well Western European) people knew about Rome then we need to get into medieval ideas of history and more importantly one needs to understand the medieval notion of *translatio*. Also since \"the dark ages\" is a notoriously vague term, I'm going to discuss primarily the 12th century.\n\nOn the first issue, when we ask what Medieval scholars *knew* about Rome, we need to first establish what that question would entail for them. Certainly Medieval authors knew a variety of Roman historians, such as Suetonius and Sallust, as well as a variety of authors writing this related to history, such as Vergil and Lucian. But this really isn't the question at hand, as the question shouldn't be, did they know these authors, but rather, how did they use these authors to create a sense of history. Now there are a variety of arguments over whether there was a bona fide sense of history in the early middle ages, the problem being twofold. First of all, they continued to maintain the classical understanding of what \"history\" was, indeed to quote Isidore:\n\n > History is so called from the Greek term ίστορεῖν (“inquire, observe”), that is, from ‘seeing’ or from ‘knowing.’ Indeed, among the ancients no one would write a history unless he had been present and had seen what was to be written down, for we grasp with our eyes things that occur better than what we gather with our hearing, since what is seen is revealed without falsehood.\n\nBut most historians of the Early Middle Ages, at least, were Monks who were simply collating other texts and stories they had heard. Secondly, again for the Early Middle Ages, we know that a lot of what they wrote simply isn't correct, indeed Smalley pointed out that the more a medieval historian quoted Suetonius (I believe) the less accurate their statement was likely to be.\n\nNow there is an important break in the twelfth century with a revival of historical thought. Now there is a theoretical underpinning to this in the increased historical discussion in the development of history as the literal sense of a text, particularly the bible. This new historical thought is particularly prevalent, and potentially developed, in the writing of Hugh of St Victor, as well as later Victorine writers, who stress the importance of knowing history and of history as the fundamentally important level of understanding for the text to be meaningful.\n\nBut we should not understand, as some have, this change as equivalent to the idea of textual criticism in the Renaissance, wherein they were interested in finding the \"real\" texts of Antiquity. Rather the historical sensibility of the twelfth century, and middle ages more generally, was presented under the theme of *translatio*. This means that the centrally important organizing concept in medieval political history was the idea of the translation of empires (or *translatio imperii*). This concept emerges out of the Christian histories of late antiquity, like those of Eusebius-Jerome and Orosius, where they used the beasts and statue in the book of Daniel as an organizing principle of world empires. Namely they argued that there was a succession of world empires concluding with the Romans. As a result, the Roman empire sort of had to be the continued empire. Thus for both their own political propaganda and for this eschatological imperative, Western Empires presented themselves as continuers of the Roman empire. It also meant that the drive of historical knowledge was not knowing things about the past, but saying things about the present, it was about drawing direct continuities between the ancient Medes and the twelfth century Germans (or whoever).\n\nNow this gets more complicated as by the twelfth century, in the heart of the investiture controversy, the donation of Constantine (or more accurately the myth thereof) became an important principle. Essentially the story was that Constantine I, after converting to Christianity, gave political rulership over the Western Roman Empire to Pope Sylvester.\n\nSo with all that in place, the Western Christians understood the Romans as the last world empire, they knew the chronology of the Romans, particularly of the imperial period, as they had gathered from the various Classical historians, as I mentioned earlier. But they were particularly interested in figuring out *what* happened in the Roman period, as that would be, to an extent, beside the point. Likewise, for them the Roman empire never fell. To go with Otto of Freisings version, the Roman empire passed from the romans to the Greeks, with the Byzantine empire, until the time of Charlemagne. Then, since Charlemagne was crowned by the Pope, the legal arbiter of the Western Roman Crown after the 'Donation of Constantine', Charlemagne became the Roman emperor, with the empire passing from the Greeks to the Franks. Finally, with the decline of the Frankish empire, and the Crowning of the German emperors like Otto I, the Roman empire passed from the Franks to the Germans. Hence, to the medieval mind, the Roman empire didn't end at all and indeed the western Roman Empire was still thriving. This is particularly evident with Frederick Barbarossa calling his empire the Holy Roman Empire, no matter what Voltaire happens to think about it.\n\nNow since this idea of history is fundamentally forward looking, so the Roman past wasn't generally viewed as something different, and the present wasn't viewed in relation to the past, as we would understand it. Rather the past was largely viewed in relation to the present. So, for example, with the illustration of emperors in the Manuscripts of Otto's work we see Augustus, Charlemagne and Otto I all represented as looking [exactly the same](_URL_0_). \n\nTL;DR: they knew essentially the history of Rome as recorded by Roman historians but they didn't understand Rome as a historical civilization in the same sense that we do. Rather Rome was still alive and well in the various successor states to the Roman empire, be it the Byzantine Empire, the Frankish Empire or the German Empire. And although it is technically true that in the Byzantine Empire the Roman Empire didn't fall till 1453, that isn't how it would have been viewed in Latin Christendom through the Middle ages. ",
"We haven’t considered the popular knowledge of Rome and its history, both in terms of its literature and its architecture.\n\nThe first thing to establish is the vast amount of Roman literature theoretically available to scholars throughout the Middle Ages, though a lot of it wasn’t systematically edited and studied until the Renaissance. Scholars estimate that about *90%* of our current store of Latin literature was preserved by Carolingian monastic copyists in the 9th and 10th centuries. How much and how widely people consulted this material varied by time and era. In the 12th century there was a so-called “Renaissance of the 12th century” in which the literature of Roman antiquity (knowledge of Greek was lost in the west by then) was widely studied, appreciated, and imitated, though often only parts of works were known. It’s in this same period that the poet Jean Bodel divided literary sources into the three “cycles” of the “matter of Britain” (the Arthurian legend”), the “matter of France” (stories of Charlemagne, like the *Song of Roland*), and the “matter of Rome,” which focused on Alexander the Great, Julius Caesar, and very fragmented knowledge of the Trojan story. A lot of source material for the details of this Roman matter was Ovid’s *Metamorphoses*, that great encyclopedia of mythology from the early 1st century CE, which was widely known and cited in the Middle Ages (though its “pagan” settings and themes were often moralized). \n\nVirgil and his *Aeneid* were adored, as was Horace. Cicero was widely known and loved, though again, only parts of him were known, perhaps most importantly his *Dream of Scipio* from the *Republic*, which had an extensive 5th-century commentary by Macrobius. It was the primary vehicle for passing down ancient cosmology to the Middle Ages. Boethius helped pass important philosophical ideas into the Middle Ages in his wildly popular *Consolation of Philosophy* (among others, King Alfred the Great made a translation of it into Old English). As qed1 noted already, Suetonius and Sallust were admired as historians. It clouds our understanding of the medieval knowledge somewhat in that these Roman historians tended to be lumped together with fiction writers under the general category of “literature.”\n\nSome knowledge of Roman history was crucial to understanding the New Testament. In the story of the Nativity, Roman soldiers were important characters (esp. in the “”Slaughter of the Innocents,” a very popular trope) and in the Passion. \n\nIn architecture, the Carolingians were shameless borrowers of Roman style, even though their ability to produce it on a monumental scale could be limited. The surviving gateway of the abbey of Corby, for example, mimics Constantine’s Arch in Rome. A mid-12th-cenury monastic pilgrim named Benedict wrote a popular tour guide to Rome called *The Marvels of Rome* (*Mirabilia urbis Romae*). It spends most of its time talking about surviving pre-Christian structures (Pantheon, Coliseum, Hadrian’s tomb, Hadrian’s Column, etc.). Around 1200 another clerical tourist arrived there, Master Gregory from England, who also wrote a guidebook, *On the Marvels of the City of Rome* (*De mirabilia urbis Romae*). He’s even less interested in Rome’s Christian history. (An aside: He was absolutely captivated by a nude statue of Venus: “It seems more a living thing than a statue,” he wrote. “I can’t explain it other than that some magical spell compelled me to go back three times to see it, even though it was two miles from where I stayed.”) The Bishop of Winchester (Henry II’s brother) visited the city in the 1100s and brought back Roman statues to England. “Romanesque” architecture, most obviously, copied the floor plan and architectural elements of the great Roman public basilicas. Roman ruins were visible all over Europe and usually noted a s such.\n\n*Very* importantly, Justinian’s 6th-century codification of Roman law, the *Corpus Iuris Civilis* was rediscovered in the late 11th century and put to wide use by the mid-twelfth. This body of Roman legal *thinking* was enormously important on shaping medieval theories of law and the state from then on.\n\nFinally, and most obviously, of course, was the use of Latin as Europe’s official educated language. This meant that a linguistic thread of continuity stretched between ancient Rome through the whole Middle Ages, into the Renaissance, and beyond into the 18th century.\n"
]
}
|
[] |
[] |
[
[
"http://www.reddit.com/r/AskHistorians/wiki/middleages#wiki_the_.22dark_ages.22"
],
[],
[],
[
"http://books.google.co.uk/books?id=MxS6-pQZzGsC&lpg=PP1&dq=historiography%20in%20the%20middle%20ages&pg=PA156#v=onepage&q&f=false"
],
[]
] |
|
g3m5c0
|
how do cleaning products actually work to kill germs?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/g3m5c0/eli5_how_do_cleaning_products_actually_work_to/
|
{
"a_id": [
"fns30ut",
"fns3ivg",
"fns58aq"
],
"score": [
4,
3,
2
],
"text": [
"Most cleaning works by simply washing the bacteria off the surface you are trying to clean. Things like bleach, disinfectant, alcohol wipes work by damaging the bacterial cell wall so it dies. For that you need the cleaning solution to contact the bacteria for a certain amount of time.",
"Most cells are enveloped by a phospholipid bilayer. This is a double layer of molecules with a polar head and a long fatty tail. The layers are arranged so that the polar heads are all in the middle and the fatty tails point in towards the cell and out towards the world, forming a waterproof barrier. For things like coronaviruses, the bit that makes them infectious is large proteins embedded in this outer layer.\n\nSoaps have a very similar molecular structure. They also have a long fatty tail, and a polar head. Traditional soaps were actually made from fat. When you wash, the fatty end of soaps bind to the oils on you skin, and the polar end binds to water molecules. This breaks up the fat and allows it to wash away.\n\nThe same thing happens to cells. The fatty end of soap attaches to the phospholipids enveloping the cell and mess up the structure. The cell falls apart and is washed away. This is all a very mechanical process which is why a bit of elbow grease is needed. You need to make sure that the oils/germs are thoroughly mixed with the soaps all the way down, rather than just on the surface layer.\n\nOther cleaning agents like bleaches and alcohols also generally work by attacking the outer membrane.",
"Chemical cleaners frequently work by either changing the surface pH or by introducing a compound that breaks up molecules used by bacteria or viruses. In fact changing the pH may also break up molecules but may be slower. Some other chemicals (surfactants) loosen things from surfaces so they can be rinsed away.\n\nSo if a bacteria is on a surface and you introduce bleach, the chlorine in the bleach destroys the cell wall, killing the bacteria. Chlorine can also breakup the dna/rna strands that make up a virus. These types of rapid chemical reactions can be quite quick. A change in pH is like dipping the bacteria in acid, it may be a slower reaction to eat away at the cell wall.\n\nSurfactants like soap or detergents make it easier to wash things done the drain. Soaps and detergents frequently combine things like a pH change as well. The pH of human skin is about 5.5 my homemade soap has surfactants AND a pH of 8.5. So when I was my hands the surfactants loosen dirt/grime and dead skin that contains bacteria AND it may loosen bacteria that happens to be on the surface. The running water rinses them off and down the drain. In addition, the pH on my hands changes from 5.5 to much closer to 8.5 for a while. This can kill or weaken any additional bacteria left on my hands.\n\nAs to, is it clean:\n\n1 - no cleaner is perfect, I'd never say 100% die. Different cleaners likely have different effective rates. Just water? Well how much grime is still left on your hands? Soap and water, likely the same question? So anywhere from poor (just water rinse, no scrubbing, visible grime left) to REALLY REALLY excellent (submerged clean white cloth in straight bleach for hours until cloth starts to dissolve)?\n\n2 - it only cleans if it hits a spot when cleaning the shower. Did you spray down everything? Get all the nooks in the grout? Inside any gaps in caulk? Leave it long enough? Scrub off any soap slime, dirt or other stuff bacteria could hide under and spray that area again. Or are you that guy that stretches their arm in goes squirt squirt a total of twice in random directions an mutters \"close enough\". Most of us are probably somewhere in the middle.\n\n3 - it does not have to be 100% germ free. Your body has an immune system for a reason. Is a small spot in the bottom back corner of the shower that didn't get well sprayed going to kill you instantly when you step into the shower? Nope, or if so your immune system was incredibly screwed up and breathing outside air might also be a problem. That said, showers that have a bunch of mold or mildew visible MIGHT kill you or others via an anaphylactic reaction. So yes you do need to clean your house/dishes/shower/etc. Your immune system is not Superman, it can be overpowered. So you should have a clean house but not necessarily a germaphobic house.\n\nThat help? Clear?"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
1fhpcq
|
Are there examples of a democratic leader being given full powers during war or peace?
|
A friend just asked me about [this executive order that Obama has signed](_URL_0_), and was using it as a criticism of Obama. The order essentially endowed the president with control over the country's vital resources during times of emergency and even peacetime. I didn't necessarily think that the executive order was that bad, because during times of war or emergency a strong leader is exactly what is needed. The U.S. government was designed to be slow and inefficient, which is exactly what is not good during a war, and thus having power concentrated could be a good thing. As for the peacetime caveat, I simply thought it was unrealistic that the president would be able to control the resources of the country without there being sufficient reason. If there wasn't any cause, there would be rebellion, and thus the order would be moot.
I was trying to think of historical examples of something described in this order happening, yet I couldn't. I know FDR vastly expanded his powers during WW2 for example, but I couldn't think of a situation in which all power was delegated to a single elected individual. Has there been?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1fhpcq/are_there_examples_of_a_democratic_leader_being/
|
{
"a_id": [
"caaehg4"
],
"score": [
5
],
"text": [
"Actually, I'm gonna use an example that you probably won't expect - I just hope it counts as a 'democratic leader.' ;)\n\nThe word **dictator.** That's a really ugly word nowadays, and it's shared with the likes of such people as the Kim dynasty, Stalin, Mao Zedong....and it's VERY commonly used in political arguments when you want to discredit your opposition (See: Fox News.) You'll roll your eyes at that and grumble about modern political discourse...but hilariously enough, *that's a mere reflection from a couple thousand years ago.* Romans did the SAME thing, except they used the word \"King.\" To them, a dictator wasn't necessarily a bad thing - well, not until Sulla came along and did his thing. In fact, a dictator was the complete opposite - it was an honour, and one that the holder was expected to give up whenever the crisis at hand had passed. Dictators were only appointed in the case of national crisis (they needed a single strong leader), and when it came to dictators...well, they had an example reminiscent of George Washington (Who's another perfect example of this, really). His name was [Cinncinatus.](_URL_0_)\n\nCinncinatus was essentially a legendary figure - much like George Washington - to the Romans. He lived in the 5th century BCE, and, due to his son being charged for murder (Apparently falsely - he was sent into exile though) and him having to pay the fine, was a REALLY poor guy. Here's how Livy describes his first appointment to the rank of dictator:\n\n > For those who reject all human things in preference to wealth, and who think that there is no place for great honor or virtue except where riches abound profusely, it is worthwhile to hear that the sole hope of the Roman people's power, L. Quinctius [Cinncinatus was named Lucius Quinctius Cinncinatus], was cultivating a farm of four *iugera* across the Tiber opposite the place where the shipyards are now, and which are called the Quinctian Meadows. There the envoys greeted him and in turn received his salutation, as he was leaning on a spade digging a ditch or while he was plowing. What is agreed is that he was definitely engaged in farm work...\n\nOops. Spoiler alert. He became dictator. Why'd he become dictator? Well, it's cause Rome was fighting the Aequi and the Sabines. The consul had led an army against them, but he'd gotten surrounded and was trapped by the Aequians. Of course, the Romans panicked at this (they liked panicking! :D) and decided they needed a dictator to save their trapped army and consul. Cinncinatus had been named suffect consul the year before, and he had made such a good impression that they unanimously voted him dictator. Back to the words of Livy, picking up off the end of the last quote!\n\n > Greetings were exchanged, and he was asked - with a prayer for divine blessing on himself and his country - to put on his toga and hear the Senate's instructions. This naturally surprised him, and, asking if all were well, he told his wife Racilia to run to their cottage and fetch his toga. The toga was brought, and, wiping the grimy sweat from his hands and face he put it on; at once the envoys from the city saluted him, with congratulations, as Dictator, invited him to enter Rome, and informed him of the terrible danger of Municius' army. A state vessel was waiting for him on the river, and on the city bank he was welcomed by his three sons who had come to meet him, then by other kinsmen and friends, and finally by nearly the whole body of senators. Closely attended by all these people and preceded by his lictors he was then escorted to his residence through streets lined with great crowds of common folk who, be it said, were by no means so pleased to see the new Dictator, as they **thought his power excessive and dreaded the way in which he was likely to use it.**\n\nLast line look like something you might see today? Maybe just a bit? ;) The Romans didn't like the idea of one man having absolute power any more than we would, yet the predicament of their army left them no choice. So Cinncinatus, being the baller of a farmer that he was, issued a decree that all men of fighting age were to rally on the *Campus Martius* and be ready for battle. He led them out and decisively defeated the Aequi and then *promptly resigned the dictatorship.* He'd only been dictator for two weeks. \n\nHe was actually called to be dictator *again* later on to put down a conspiracy, and again resigned it very quickly after taking it. He was pretty much a pretty cool guy all around, and, late in his life when one of his sons was being tried for military incompetency, he got off with the defense \"Who's gonna tell my dad about his and break the old man's heart?\"\n\nThe office of dictator was only sullied (Hee, I made a silly) when Sulla took the office and twisted it to his own ends. But that's a completely different story :D\n\nThe Romans actually delegated this power quite often - it was stopped after the Second Punic War for a time, because they feared the amount of power that the Dictator had. The most common reason for someone to be appointed Dictator was to lead an army (Rome's generals were politicians and vice versa, so having one guy labeled to lead an army commander-in-chief style was a necessity on many occasions). If you have any questions on that, feel free to ask! (But please don't try to equate it TOOOOOO much to modern politics. I avoided that part of the question for a reason ;) )"
]
}
|
[] |
[
"http://www.whitehouse.gov/the-press-office/2012/03/16/executive-order-national-defense-resources-preparedness"
] |
[
[
"http://en.wikipedia.org/wiki/Cinncinatus"
]
] |
|
1uuhl0
|
Why is it that most products that you find in the bathroom have only 1% of the main ingredient?
|
On certain items, you will see it says something like Active Ingredients: Phenol................................1%.
Why does the main compound have such a low representation?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1uuhl0/why_is_it_that_most_products_that_you_find_in_the/
|
{
"a_id": [
"cem4k5c",
"cem8v6v"
],
"score": [
3,
2
],
"text": [
"There are many different reasons. Sometimes it is a safety concern (such as hydrogen peroxide being sold as a 3% solution. This is to keep the user safe and to maintain product integrity.) In creams and whatnot, a delivery system is necessary, usually water based, which makes up a large portion of the product. This is to help the user dispense the correct dosage easily, among other purposes. Those are two of the main points that come to mind this morning. ",
"Most active ingredients are most effective within a certain range. Below the range they have little to no effect and above the range they can be dangerous causing severe damage. For example, skin products have acids or alcohols which dehydrate your skin even at low concentrations. If the concentration increased, instead of the product being a \"cleanser\" it could cause scars and burns. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
3y0kut
|
why are the biggest tech companies in america on the west coast?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3y0kut/eli5_why_are_the_biggest_tech_companies_in/
|
{
"a_id": [
"cy9gl5x"
],
"score": [
3
],
"text": [
"Two reasons that I know of:\n\nOne, the simple network effect. Many early tech companies were in the area, and especially in the early days, new tech companies usually formed when a few engineers with an idea left a previous company to pursue their new idea. And they'd stick in the area because that's where all the other high tech engineers were— you want to be able to hire people.\n\nTwo, a side effect of [military spending.](_URL_0_) WWII radar research and the Manhattan Project moved an assload of smart, driven people into the general area. Then, tons of Cold War military research spending going into places like Stanford, produced a lot of tech investment.\n\nI suspect California's higher education system also has something to do with it— until relatively recently, it was possible for any resident in the top ~1/8 or so of their high school class to get a university education there, at a world-class university. (I think California schools were funded by the old Land Grant system, designed to provide a scholarship to anyone who would really be able to benefit from it.) Obviously if you have a bunch of people with good education (and without super debt) they are more likely to produce powerhouses like Silicon Valley."
]
}
|
[] |
[] |
[
[
"http://www.tomshardware.com/news/secret-history-silicon-valley-gave-rise-modern-tech-giants,4713.html"
]
] |
||
2zlwq6
|
why can a watch be made to remain accurate for years, but the second hand never be made to consistently lines up with the tick marks?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2zlwq6/eli5_why_can_a_watch_be_made_to_remain_accurate/
|
{
"a_id": [
"cpk3qu8",
"cpk6pu6"
],
"score": [
4,
3
],
"text": [
"I know this is speculation, and I'm sorry, but I'm pretty sure this is to do with the error of parallax - which basically has to do with the fact that your viewing angles may not always be perfect so that you misinterpret the true location of the second hand, even if it is perfectly on the tick mark. ",
"/u/malnurtured999 gave a good answer but it could also just be your unit has a slight manufacturing defect. I own several mechanical watches and one of the less expensive ones has a defect where the diving bezel doesn't exactly line up with the ticks."
]
}
|
[] |
[] |
[
[],
[]
] |
||
i3fjl
|
How long does it take for tourniquets to start causing tissue damage?
|
I know that applying a tourniquet leads to tissue damage by way of hypoxia, but I'm having difficulty finding an answer to this particular question. Also, can applying the tourniquet to an extremity also cause tissue damage in other parts of the body?
|
askscience
|
http://www.reddit.com/r/askscience/comments/i3fjl/how_long_does_it_take_for_tourniquets_to_start/
|
{
"a_id": [
"c20lag3"
],
"score": [
4
],
"text": [
"I don't know of any good data on the issue, but for orthopedic surgery we will use a tourniquet for up to 2 hours at a time, which is generally considered low risk. We also try to keep tourniquet pressure to a minimum. After a recovery period, it is also considered safe to reapply the tourniquet, but there is not good data that I know of to guide the length of recovery and subsequent tourniquet application.\n\nHere's a random paper I found on physiologic changes following tourniquet release: _URL_0_"
]
}
|
[] |
[] |
[
[
"http://www.eymj.org/Synapse/Data/PDFData/0069YMJ/ymj-33-153.pdf"
]
] |
|
3m6l5c
|
Has the " speed of gravity" actually been measured?
|
There is a ton of comments on the thred about the disapearing Sun - if we would continue to orbit a non-existing object.
Generally it is assumed that gravity would propagate at c, but has it been actually measured? Could we measure it? I have red about atomic clocks that can detect g changing while moving the instrument up and down few meters (or less?) Could such an instrument be used to detect, say, Jupiter and compare where the light is comming from and where is the gravity comming from. Perhaps the instrumsnt can be put in an orbit or the surface (or orbit)of the moon..or simply interplanetary space to get a better reading?
|
askscience
|
https://www.reddit.com/r/askscience/comments/3m6l5c/has_the_speed_of_gravity_actually_been_measured/
|
{
"a_id": [
"cvd0eu0"
],
"score": [
9
],
"text": [
"Sort of, in an indirect way. We haven't yet directly measured the propagation time of changes in gravity, although we likely will very soon as Advanced LIGO is expected to detect the first gravitational waves in the next few years. There are two Advanced LIGO detectors, one in Washington and one in Louisiana, and from the time delay between the two detectors the speed of the gravitational wave can be measured.\n\nIndirectly, the speed of gravitational waves is deeply embedded in the foundations of general relativity. The fact that they travel at exactly the speed of light is not something that can be arbitrarily adjusted without changing other predictions of GR, all of which have so far passed experimental tests. (The most relevant is probably the [Hulse-Taylor binary pulsar](_URL_0_) that indirectly shows the existence of gravitational waves in the right amount. Changing their propagation speed would affect the inspiral rate of this binary system.)\n\nAs an interesting fact: you propose comparing the direction of Jupiter's gravity to the direction of the light it emits. In general relativity, the gravitational pull of a moving object points exactly towards where it *will be* when the gravity gets to you. For this reason, the Earth orbits the point where the Sun *is right now* rather than where it was 8 light-minutes ago, when the gravity was 'emitted.' Light from the object, however, comes from the direction that the object was in when the light was emitted. So, even though the effects travel at the same speed, they will point in different directions."
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/PSR_B1913%2B16"
]
] |
|
6507xm
|
How did the planes that dropped nukes on Japan penetrate that air space without conflicr?
|
I hear about battles being so hard fought and dangerous, yet the US (seemingly) easily flew two planes into Japan mainland and dropped nukes on them.
What was the context for this mission? Was it stealth based? Or did we just take a very brazen step and broke rules of engagement in an otherwise unprotected area to do this?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/6507xm/how_did_the_planes_that_dropped_nukes_on_japan/
|
{
"a_id": [
"dg6dp8m"
],
"score": [
8
],
"text": [
"Hi there -- while there's always more discussion to be had here, you may be interested in this [older thread on the topic](_URL_0_) which explains multiple reasons why the atomic bombing missions were successful. "
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/35rwix/how_were_single_unescorted_bombers_able_to/"
]
] |
|
3py1ev
|
why do so little people like history?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3py1ev/eli5why_do_so_little_people_like_history/
|
{
"a_id": [
"cwafn2n",
"cwagrks"
],
"score": [
2,
3
],
"text": [
"I guess there's different reasons for it, my own reason is that i hate stupidly memorizing things. So school kinda ruined history for me, i just don't think it makes sense to force people to know specific dates - it's just no use to me. If i want to know those things i can just check them.\n\nThat's probably why i never felt like looking in a history book again after i finished school. If it would be only story i'd probably like it, but most of the time it just makes me memorize useless dates. Ain't nobody got time for that!",
"Good history teachers are hard to find. Rather than presenting history as a series of interconnected events, most history classes present a list of names and dates, which they then expect you to regurgitate on a test. Most people know that Eli Whitney invented the cotton gin, but I would wager that very few could explain what a cotton gin actually is or why it was important."
]
}
|
[] |
[] |
[
[],
[]
] |
||
17nmcq
|
How to identify intron sequences in mRNA?
|
How do I find the exact place where the intron starts and ends in an mRNA sequence?
Thanks in advance!
|
askscience
|
http://www.reddit.com/r/askscience/comments/17nmcq/how_to_identify_intron_sequences_in_mrna/
|
{
"a_id": [
"c8796bq",
"c87dex6"
],
"score": [
2,
2
],
"text": [
"Introns are removed by a ribonuclear complex called a splicesome that recognises motifs called a splice donor site (at the 5' end) and a slice acceptor site (at the 3' end). About 50 nucleotides upstream (before) the acceptor site will be a branch site that is important in excising the intron.\n\nWhat you need to look for is a donor site, which will generally have the sequence (A/C)AG/GUAA. Then the acceptor site downstream will generally have N(C/T)AG/G. About 50 nucleotides upstream will be the branch site with consensus sequence of CU(A/G)A(C/U) followed by a pyrimidine-rich sequence. I say generally here because there isn't an invariant sequence that is always used. The most conserved nucleotides are the AG in the donor, the A in the branch, and the AG in the acceptor. The nucleotides surrounding these determine the strength of the site.",
"If you are interested in predicting splice sites within an RNA, there are a number of computational approaches that try to search for sequences that fit splice criteria (as Hashshashin7 pointed out). These are not always accurate, since the sequence of the acceptor and donor can be pretty degenerate, but the scores can at least give you an idea of where splicing may take place. NetGene2 (_URL_1_) is an example of this.\n\nThat said, RNA splicing within a cell can be pretty messy; an obvious splice site may not be used, or what appears to be a poor junction could be readily spliced. On top of this, some splice sites are used differentially. Deep-sequencing of RNAs is revealing that alternative splicing can be common and result in certain RNAs haveing several isoforms. These alternative RNAs are not simply accidents due to the ambiguous nature of splice motifs, but appear functional and regulated by the cell.\n\nReference: _URL_0_"
]
}
|
[] |
[] |
[
[],
[
"http://www.plosbiology.org/article/info%3Adoi%2F10.1371%2Fjournal.pbio.1001229",
"http://www.cbs.dtu.dk/services/NetGene2/"
]
] |
|
28oyel
|
why is female genital mutilation a thing? why did the swedish school force the procedure upon the girls?
|
I just don't get it. I'm probably pissing tons of MRA's off by saying it, but I can understand circumcision, there's religion and hygiene behind it. But doing the same for females? Why do they have to enact laws against that shit? Why don't schools know better than to cut peoples' kids' fucking genitals off? Perhaps I'm misunderstanding the whole situation. But then again, that's why I'm posting it here!
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/28oyel/eli5_why_is_female_genital_mutilation_a_thing_why/
|
{
"a_id": [
"cid0oda",
"cidif10"
],
"score": [
6,
3
],
"text": [
"The school didn't force the students to do anything. It just happens to be attended mostly by immigrants, and many of the girls were discovered to have undergone the procedure. This mostly happens during the holidays when the parents take the girls on trips to countries where the procedure is legal to perform.",
"Why are you ok with male circumcision?"
]
}
|
[] |
[] |
[
[],
[]
] |
|
29vg6a
|
Could intelligent life have appeared very early in the Universe?
|
We're talking years, or thousands or even hundreds of thousands of years after the big bang has happened
|
askscience
|
http://www.reddit.com/r/askscience/comments/29vg6a/could_intelligent_life_have_appeared_very_early/
|
{
"a_id": [
"ciovdko",
"cip0jh2",
"cip2hnd",
"cip63cg"
],
"score": [
31,
2,
9,
3
],
"text": [
"There were no unionized atoms at all until about 400,000 years after the big bang, and no atoms heavier than lithium until about 500 million years later. So, any life would have been of a form inconceivable to us.",
"We don't really have any way of knowing or even approaching this question. We define human civilization to be intelligent and its been around for maybe 9,000 years if we are being generous. There was so much time since the big bang, while we might be able to somewhat reconstruct galatic movements and the formation of say, our solar system, we are almost clueless to what happened on a smaller scale. There just isn't any way to know! That said, our complete lack of contact with such civilizations is at least evidence for the claim that they don't exist near enough to us to matter. We can say with some certainty that civilizations didn't exist that transmitted radio signals in certain time periods because we've \"listened\" for them, but other than a few very specific examples like that, any answer to your question besides \"we have no good way of finding out\" is heavily speculative.",
"It depends on what you consider the minimum conditions for life to appear. No lifeform as we know it could survive anywhere in this early universe.\n\n_URL_0_\n\nBefore ~377 000 years, there was no atoms as to speak of. At this points atoms started to form, but there was only the lightest of the elements, no complex chemistry was possible so such an early life would have to rely on something else than cehmistry.\n\nYou will have to wait tens of millions of years to get the first stars. But then you only have stars. It probably took a whole stellar generation (stars living and dying) for the first planets to assemble. About 4 billions of years for our Earth.\n\nI won't say that it is totally impossible for non hadronic matter to harbor life, but I am quite sure that I have no idea on how it would work. Take also into account that at this point the conditions of the universe were changing quickly compared to the speed of evolution as we know it. ",
"The components that are necessary for life as we know it had not developed yet. They are formed through the self destruction of stars and their fusing of atoms to create heavier elements. Hydrogen and Helium would have been over present for quite some time (still are the most abundant) while other structures such as iron and oxygen would take a very long time to come about. So yes it is possible, mainly because *anything* is possible but that doesn't mean it is very close to being even remotely likely.\n\nEdit to make sure I got my point across about how implausible it would be"
]
}
|
[] |
[] |
[
[],
[],
[
"http://en.wikipedia.org/wiki/Chronology_of_the_universe#Recombination"
],
[]
] |
|
5u6z00
|
if we can't control where fat is lost/gained from, how are we so symmetrical? why isn't one hand or one arm fatter than the other?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5u6z00/eli5_if_we_cant_control_where_fat_is_lostgained/
|
{
"a_id": [
"ddrt1gv",
"ddrt3uj",
"dds2hl8"
],
"score": [
5,
3,
2
],
"text": [
"For the same reason.\n\nWhen your body stores fat it tries to spread it around as much as possible.",
"You can't change it intentionally but your body knows where to store fat. It doesn't ask you where to do it because it already knows which place has more fat and directs the fat to another place.",
"The mechanism that distributes fat to one arm is the same that does on the other arm. Normally there's no reason to be different. However, the way fat goes to your hip isn't the same for the fat that goes to your chest. Those are supposed to be different.\n"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
bn4221
|
Why did Asians develop a better food cuisine than Europeans?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/bn4221/why_did_asians_develop_a_better_food_cuisine_than/
|
{
"a_id": [
"en22mpi"
],
"score": [
2
],
"text": [
"This submission has been removed because it violates the [rule on poll-type questions](_URL_0_). These questions do not lend themselves to answers with a firm foundation in sources and research, and the resulting threads usually turn into monsters with enormous speculation and little focussed discussion. Questions about the \"most\", the \"worst\", or other value judgments usually lead to vague, subjective, and speculative answers. For further information, please consult [this Roundtable discussion](_URL_1_).\n\nFor questions of this type, we ask that you redirect them to more appropriate subreddits, such as /r/history or /r/askhistory."
]
}
|
[] |
[] |
[
[
"http://www.reddit.com/r/AskHistorians/wiki/rules#wiki_no_.22poll.22-type_questions",
"https://www.reddit.com/r/AskHistorians/comments/48hjn0/rules_roundtable_6_the_no_polltype_questions_rule/"
]
] |
||
1qvwu4
|
convergence vs divergence
|
Could anyone please explain to me what these terms means? I'm writing a text where I'm asked to give a characteristic of these terms.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1qvwu4/eli5_convergence_vs_divergence/
|
{
"a_id": [
"cdh1ql1"
],
"score": [
4
],
"text": [
"Convergence is *converging*; coming together or meeting.\n\nDivergence is *diverging*; separating or moving apart."
]
}
|
[] |
[] |
[
[]
] |
|
25ogzz
|
How is energy prioritized between organs in humans?
|
If there is a lack of energy within the body, how does the body distribute it amongst organs or processes? Is it dependent on the particular "type" of energy there is a lack of, e.g. starvation versus a lack of oxygen?
|
askscience
|
http://www.reddit.com/r/askscience/comments/25ogzz/how_is_energy_prioritized_between_organs_in_humans/
|
{
"a_id": [
"chjklky"
],
"score": [
2
],
"text": [
"We redirect blood flow. The blood carries oxygen and carries nutrients: the two things we need to create our body's main energy carrier - ATP. Now, our body has a nice big store of macronutrients, so we can last without them for a much longer time than oxygen. The thing that tends to cause the biggest threat, in terms of \"distribution\", is thus oxygen.\n\nOur body is also one big interconnected circulatory system, so the only time a single body part tends to become deficient in oxygen is if the blood flow gets blocked off (like in a heart attack, or a stroke, or if something outside the blood vessel compresses it). Then we can't do much because there's a physical barrier in the way. But what our body *can* do something about is in situations where there is *increased energy demand* (like exercise), or in *shock* (which is where you don't have enough blood to supply your organs - like if someone chopped your arm off). What our body does to make sure things we need get enough oxygen is by *dilating and constricting* blood vessels. So if I'm running, then the blood vessels supplying the important musculature would dilate, and the blood vessels supplying somewhere less important like the intestines would constrict. So this redirects more blood to go to the muscles.\n\nIn cases where there's global inadequate blood supply, like if you're losing blood, your body prioritises organs. It'll constrict blood supply to places like your intestines, your kidneys and your pancreas to try to maintain supply to the more immediately important organs like the brain, heart and lungs.\n\nThere are also cases where you can lack oxygen in your blood (hypoxaemia), but I'm unsure of the global compensatory responses for that in terms of distribution. I'd imagine it's the same as in circulatory shock, but I can't be sure. "
]
}
|
[] |
[] |
[
[]
] |
|
g3tcba
|
why do so many disney child stars lose their minds?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/g3tcba/eli5_why_do_so_many_disney_child_stars_lose_their/
|
{
"a_id": [
"fntb5s8",
"fntb9gq",
"fntbkqm"
],
"score": [
2,
3,
3
],
"text": [
"Because most of them are ridden into exhaustion by their parents. Parents are using the kids as meal tickets so they push them to be perfect and do everything to keep up the fame.\n\nUsually drives the kids to drinking and drugs in their late teens.\n\nIt's not just Disney stars. Look at the child beauty pageant circuit (Honey Boo Boo comes to mind).",
"Power, fame and money can corrupt a person or make them more powerful. When you are teenager, with a lot of money and bad company , it's easy to become overconfident and think like a very immature person, even worse than what they initially were. And it gets so out of control that they are filled with a lot of ego and suddenly start disrespting people who haven't achieved their level of success or have talent and skills that can match theirs so they end up doing something very silly and get misguided by everyone.",
"They don't Disney hires more child actors than any other single production company so when a child actor has problems, its more likely they've worked for Disney at some time than anyone else. In addition, there is some evidence that children (and adults) who seek the entertainment field start off with more mental problems than most."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
3ldvke
|
If the eye is opened during sleep will the brain still process the visual information?
|
askscience
|
https://www.reddit.com/r/askscience/comments/3ldvke/if_the_eye_is_opened_during_sleep_will_the_brain/
|
{
"a_id": [
"cv5r6r6",
"cv5tp44"
],
"score": [
19,
2
],
"text": [
"No, and maybe!\n \nOK. During sleep, particularly REM sleep, the ascending sensory pathways are shut down by strong inhibition. On the other hand, visual input provides a very strong drive to inhibit sleep. Enough light in the eyes, and you stand a good chance of waking up. However, lower amplitude visual inputs should be shut off. ",
"A good part of the visual processing pathway is involved in sleep, so in a way no, the brain is too busy sleeping to concern itself with the outside world.\n\nAlso brains don't magically shutoff when eyes are closed. The state of the eye-lid has little bearing on the cognitive state. Offcourse what part opens the lid might try to connect with outside reality. However the eye is special in the sense that it is not involved in sleep paralysis. For example your arm is pretty much shutoff. If the waking happens only partially it is possible to be awake in the awereness sense while your appendage sleep paralysis is still on. The failed attempt to move your arm can be a very alarming subjective experience but is mostly harmless and won't stay for long.\n\nIt is more like sleepwalking in that a sleepwalker might not be hitting walls etc but they certainly do walk differently than awake. However \"sleeplooking\" is such a normal part of sleep that it can almost be assumed to be apart of it (but usually done eyelid closed).\n\nAlso even if the brain does process the visual stimulus it migth not be doing so to the same extent as normal. Strong external stimuli have been known to induce dreams with similar qualitities so such things as the coloring of the ambient lighting changing can very well be percieved. However there is a phenomenon of \"blindsight\" where a person can't cognitively verbally describe what he is looking at but when he is given a task that requires hand-eye coordination he can pull it off. So in a importnat sense he doesn't see in that he doesn't have subjective perceptional representation of the object (and the case isn't that he is lying) but in a sense his brains are capable atleast for some tasks to succesfully incorporate the information. Its like his subconciousness sees but his overconciousness doesn't. The state on how they eye is used during sleep might fall in a similar inbetween state or in a kind of reverse way where bright lighting might induce happy dreams or dreams of heaven where instead of particular images only the very abstract concept gets throught."
]
}
|
[] |
[] |
[
[],
[]
] |
||
7903sz
|
[Math] What is the size of a differential?
|
I've done differential and integral calculus, and the question is bugging me more and more. Something doesn't seem right to me, especially in integral calculus. The width of the Riemann Sums is dx, and dx was taught to me as "infinitely small". And to me, infinitely small is just 0. And summing 0's even for the time left in all universes won't do anything. What is wrong here? Are our minds ( or just mine -.- ) just too stupid to grasp the concept of differentials and infinity? What would be the decimal representation of a dx? Not 1, not 0.1 and clearly not 0. I feel as if I were playing with magic.
Edit: I forgot how to write.
|
askscience
|
https://www.reddit.com/r/askscience/comments/7903sz/math_what_is_the_size_of_a_differential/
|
{
"a_id": [
"doy3deq"
],
"score": [
39
],
"text": [
"\"dx\" is not a number. In fact, you can do all basic calculus without needing to even mention that it exists. The thing that's wrong with them is that they actually don't make sense, so it's totally reasonable to be confused about them if you think about them too much.\n\nThe key thing in Calculus is *limits*. Everything is limits. There are no differentials. Derivatives are not fractions of differentials, they are the limit of the slope of secant lines as the distance between the two points on the secant line goes to zero. No differentials mentioned anywhere. Integrals are not sums of differentials. Integrals are limits of Riemann sums, which are finite sums whose constituent rectangles have finite width, and the limit is as the width of these goes to zero. Nothing to do with summing infinitely many differentials or anything. Even differential equations and separation of variables are clever uses of the chain rule that don't need differentials to make sense.\n\nLimits are the name of the game in Calculus. Intuitively, limits are systematic ways to approximate things within any arbitrarily precise error. The value of the limit is what these approximations approach a you make the error arbitrarily small (if it exists). It's quite a shame that limits are basically forgotten after the first three weeks in Calculus as literally everything in Calculus is an application of limits. The epsilon-delta definition is the key to understanding them and how they relate to approximation, yet this is glossed over if mentioned at all.\n\nIn higher dimensional Calculus, the notion of the differential becomes useful, but it is nothing resembling an \"arbitrarily small value\" or any other thing mentioned in Calc1 about them. Differentials are ways to keep track of and work with directional derivatives. They are vectors that encode higher dimensional derivative information about a function in a convenient package. So, really, all the stuff about differentials in Calc 1 could be totally eliminated and students understanding about Calculus would not change (and probably improve). If I were you, I would try to make sense of limits and forget about making sense of differentials, because they don't make sense so there's nothing for you to figure out!\n\n-------\n\nDisclaimer. Yes, there is nonstandard calculus, the hyperreals, surreal numbers etc where some of the intuitive notions about differentials make sense. But this is even farther from anything in calculus than anything else, require a level of mathematical maturity that calc students don't even come close to, and are generally pretty esoteric within math itself. Fun and interesting things to study, but not really *super* important. They are far more abstract than limits and traditional differentials, so anyone looking for an easy way to use differentials rather than limits will have a hard time."
]
}
|
[] |
[] |
[
[]
] |
|
7dfwuj
|
WW2 massive cannons
|
My friend is playing call of duty the new WW2 one that just came out. There’s a map with a GIANT cannon in the middle of it. It’s such a massive structure and it sits on a railroad track. I’m just curious what these were used for?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7dfwuj/ww2_massive_cannons/
|
{
"a_id": [
"dpxi7y4"
],
"score": [
6
],
"text": [
"So, the one that is in COD WWII, I'm almost certain represents the 'Schwerer Gustav', the largest calibre weapon ever used in combat. The Gustav is part of a type of artillery called railway guns, because they were always moved via railways rather than roads. In general railway guns are designed to tackle heavily fortified positions and towns, but also fire in safety out of range of the enemy's artillery. The problem is these artillery pieces required to break through fortified concrete are so large that they have to be transported via railways, hence the name.\n\nThe Schwerer Gustav had a total length of over 43m, and had a barrel length of 32.5m. It fired an artillery shell that was 80 cm wide, and was originally designed to punch through seven metres of reinforced concrete. This artillery piece was so powerful it could accurately hit a target 39km away! In WWII it saw action in the Crimea, particularly the Siege of Sevastopol, where is knocked out coastal guns and damaged the Gorky Fortresses. \n\nSo simply put: The bigger and stronger defences a target had, the more powerful the artillery needed to be to damage it. This meant some artillery pieces were so large and so powerful they could only be carried via railways. \n\n[Here are some pictures of the Gustav](_URL_0_)\n\n\n**If you want to read more:**\n\n\nEngelmann, Joachim (1993) *German Railroad Guns. Armor in Action*\n\n\nZaloga, Steven J; Dennis, Peter (2016) *Railway guns of WWII*\n"
]
}
|
[] |
[] |
[
[
"http://highpowerrocketry.blogspot.co.uk/2011/06/schwerer-gustav-and-dora-railway-siege.html"
]
] |
|
2fo8m8
|
if i mistakenly step on my dog or stumble on him, then rightaway cuddle him as an "apology", will he interpret it this way?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2fo8m8/eli5_if_i_mistakenly_step_on_my_dog_or_stumble_on/
|
{
"a_id": [
"ckb3sux"
],
"score": [
5
],
"text": [
"No. I think the Oatmeal did it best: \n\n_URL_0_\n\nAbout a quarter of the way down. Its' a joke, but that sums it up pretty well. "
]
}
|
[] |
[] |
[
[
"http://theoatmeal.com/comics/dog_paradox"
]
] |
||
85zeck
|
how does nasa and other space agency’s manage to land a rover/probe on an moving asteroid?
|
Title.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/85zeck/eli5_how_does_nasa_and_other_space_agencys_manage/
|
{
"a_id": [
"dw18sd5",
"dw19ufu",
"dw1ljez"
],
"score": [
10,
2,
6
],
"text": [
"We're really really good at intelligent computer and propulsion systems.\n\nThere's four steps to doing it.\n\nThe first is launching. Got that down quite well with multi-stage rockets.\n\nThe second is getting to the asteroid and matching its orbit. Got that down quite well with the ability to figure out where the asteroid's orbit will take it.\n\nThe third is selecting a spot to land. That can be performed by imaging the asteroid and determining a likely spot.\n\nThe final one is programming the propulsion systems on the orbiter part to drop its lander on the asteroid. With all the data you've collected so far, this is also achievable using sophisticated computer-driven propulsion systems with distance-detection measurement devices and self-correcting capability.\n\nAll of that stuff, we have now. We just need to do a lot of tweaking and testing and solid engineering to make it all work together.\n\n",
"Imagine jumping from one car to another while moving 60 miles per hour. The wind makes it a little difficult to do so in reality, but imagine that the air, therefore wind does not exist.\n\nIt would be quite simple to jump across, no issues. ",
"Others have already given the explanation, I just want to address an underlying assumption you seem to be making:\n\nYou might as well ask how people managed to land on a moving moon, i.e. our Moon. Nothing in space is standing still. Everything is moving in orbit around something else. Our sun orbits around the centre of the galaxy. Our galaxy and the local galaxy group orbit around their centre of gravity. What you want to do is make sure you orbit the centre of gravity (the Sun, in this case) at the same speed and with the same orbital parameters that the asteroid does. So it's like the car analogy that u/Xalteox made: when you're next to an asteroid at exactly the same speed, you wouldn't notice that the asteroid is moving.\n\nSo how do we get to the asteroid?\n\nVery basically (and I'll skip the launch part), you're in Earth orbit, travelling a few hundred kilometres above the surface at around 7,700 m/s - that's roughly 17,000 mph or 28,000 km/h. \n\nWe need to change our orbit so it crosses that of the asteroid. Timing is important - crossing the asteroid's orbit when it's on the other side of the sun is useless. The time where you can burn to intercept is the transfer window. Theoretically, it wouldn't matter that much, only you would need very, *very* large amounts of fuel, a much larger engine to propel the much heavier spacecraft and maybe several billions of dollars. That's not feasable, so we wait for the transfer window.\n \nOnce it comes, we burn the engine for a while until we're at such a speed that Earth's gravity can no longer pull us back around. Think of a car on a racetrack that's too fast to go around a curve and skids off the track - that's what we're trying to do here. Only our result will be that we'll change from orbiting Earth to orbiting the Sun.\n\nOnce we are at the intercept point (and hopefully we got everything right and the asteroid is also there), we burn the engines again for a while, changing our speed until our orbit of the Sun matches that of the asteroid.\n\nAnd then we do what the other posters said: use thrusters to gently manoeuvre us down to the surface.\n\nAs I said, this is the very basic version. If you want to try something like that, I'll shamelessly advise you to download the free demo version of Kerbal Space Program from Steam. Once you've become addicted to the game like most people (including me), there are mods to make it as realistic (i.e. very hard) as home simulations can be, n-body physics and all."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
4x7pmz
|
When the Vikings showed up in (what is now) Eastern Canada would the natives there have already had bows? If "no" why didn't they adopt it from the Norse?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4x7pmz/when_the_vikings_showed_up_in_what_is_now_eastern/
|
{
"a_id": [
"d6de4u3"
],
"score": [
22
],
"text": [
"Some of the Native Americans did have bows upon the Norse arrival, depending on what culture they belonged to. The natives that inhabited Vinland (Newfoundland) at the time of Norse contact were known as the Beothuk. The Beothuk had bow and arrow technology, which they used to hunt prey such as sea birds or caribou. In the sagas of the Norse exploration of Vinland mention the Skraelings (the Norse term for the local native population) as possessing bow, and one individual even offerred to trade his ornate bow for a metal knife belonging to the Norse.\n\nHowever not all native populations did posess bow and arrow technology. For reasons not entirely known to modern historians, the Dorset culture which inhabited the northern reaches of modern Canada including Baffin Island did not have bow and arrow technology. The Dorset instead chose to use heavier lance and spear weapons to hunt sea mammals on the arctic ice. They never adapted the bow and arrow from either the norse or their native counterparts, and their relative lack of such technology may have played a role in their ultimate extinction due to climactic changes and their conflict with the Thule people. The Thule did have bows, which helped them in combat as they defeated both the Dorset peoples and ultimately helped expel the Norse from the North American continent."
]
}
|
[] |
[] |
[
[]
] |
||
1154bm
|
bright momentary reflection seen on a phone screen reflecting from a desktop lcd while scrolling.
|
Ok, ELI5, i just stumbled on something weird. I have a TFT monitor staring at my daily email, and i have an old smartphone turned off, in front of the screen, on my desk.
While scrolling the email, i can see the reflection on my smartphone screen - only when scrolling - as very bright, with inverted colors(white text on black background) but as soon as i stop scrolling the reflection disappears and it's barely visible.
Why is this happening and why does it get momentarily brighter ONLY when scrolling even by a tiny amount.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1154bm/eli5bright_momentary_reflection_seen_on_a_phone/
|
{
"a_id": [
"c6jh2pe"
],
"score": [
2
],
"text": [
"Go to r/askscience"
]
}
|
[] |
[] |
[
[]
] |
|
1yxdvm
|
can a commercial aircraft, like a boeing 747, do a looping?
|
If not, why not? How about a barrel roll?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1yxdvm/eli5_can_a_commercial_aircraft_like_a_boeing_747/
|
{
"a_id": [
"cfom10h"
],
"score": [
3
],
"text": [
"They can't loop in the nice circular sense. They don't have enough thrust to make it over the loop even if they start at max speed. However, if you're careful, you can get far enough over than, when you stall out, you're past vertical and can \"flop\" over to complete the loop in a rather ungrateful manner. You are extremely likely to over speed when pulling back to level. \n\nA barrel roll is no problem. 707s have done it at least twice for publicity. "
]
}
|
[] |
[] |
[
[]
] |
|
24dept
|
If nothing can travel faster than the speed of light, how come there are limits to our observable universe?
|
Apologies if this questions doesn't fully make sense.
There are parts of the universe that are so far away that we cant see them, simply because light hasn't had enough time to travel that distance. Yet the universe expanded from a singularity. If this expansion happened at the speed of light, shouldn't the whole universe be visible?
|
askscience
|
http://www.reddit.com/r/askscience/comments/24dept/if_nothing_can_travel_faster_than_the_speed_of/
|
{
"a_id": [
"ch62pwk",
"ch62sdj"
],
"score": [
10,
3
],
"text": [
"First, the universe \"beginning\" in a singularity does not necessarily imply that it is finite. One can have a universe that \"starts\" in a singularity while being infinite in extent at all times after the singularity. See my standard analogy [here](_URL_0_), for example.\n\nSecond, the statement that \"nothing can travel faster than the speed of light\" is a *local* statement. It says that the distance between you and something in your immediate vicinity cannot increase faster than the speed of light. This is because the only significant way in which the distance between you and something in your immediate vicinity can increase is if that thing actually moves from one point to another. The speed-of-light limit is a limit on that sort of behavior.\n\nHowever, on very large scales, there is another way in which the distance between you and such an object might increase: expansion of space. That is, the distance between you and that object may *just get bigger* over time. There is no similar limit on the rate at which the distance between you and the object can increase through this method. For elaboration on this point, see my comment [here](_URL_1_). The end-result is that objects can (and did and continue to) recede from us at speeds well above the speed of light.",
"The expansion of the Universe is a different thing from motion through it. The motion of information through the Universe is limited by the speed of light, but there are plenty of things that *don't* carry information, which do move faster than the speed of light. For example, back when people still used analog oscilloscopes (which shot a beam of electrons onto a phosphor screen to create a moving spot of light), Tektronix used to make high-end oscilloscopes whose spot moved faster than the speed of light across the screen. That's possible because the spot didn't carry any information from one side of the screen to the other, it only deposited information there from the electron gun at the back of the screen. Other non-causal effects, like the \"spot\" made by the a row of phased strobelights next to an airport runway, can also go faster than light. The trick is that the signal to turn on the strobelights only propagates at the speed of light, so you have to trigger the pattern (say, from the control tower) in advance. That kind of effect is called a \"phase speed\", and it can be as high as you like, so long as you set it up in advance.\n\nThe expansion of the Universe is a phase speed. No information is carried from the distant galaxies to us faster than the speed of light, which is why there might be distant stuff that is simply receding too fast for its light to ever reach us.\n"
]
}
|
[] |
[] |
[
[
"http://www.reddit.com/r/askscience/comments/14wvsj/because_we_know_approximately_when_the_big_bang/c7h636k",
"http://www.reddit.com/r/explainlikeimfive/comments/rp5g8/i_thought_i_was_decent_at_math_how_can_the/c47imnu"
],
[]
] |
|
1zp0oq
|
How bad is the space junk problem?
|
Was just watching Gravity with my friend and we started talking about space junk, the old satellites and debris floating around up there at astronomical speeds, and were wondering how bad it actually is. Has it ever interfered with a mission to outer space? Is it a legitimate worry our astronauts have to account for?
|
askscience
|
http://www.reddit.com/r/askscience/comments/1zp0oq/how_bad_is_the_space_junk_problem/
|
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"This is a very good question that unfortunately has no clear cut answer. There are satellites falling to Earth all the time yet most end up burning up in the atmosphere upon re-entry. Also one thing Gravity does get wrong is that everything is kept at the same 'height' from the top of the atmosphere and everything is in the same elliptical orbit. This is not the case. There is not satellite ring swarming above us, but more of a chaotic dance of fly-by's, odd orbital patterns and planned descents into a fire-y oblivion.\n\nNASA has this cool tracking [site](_URL_0_) that shows a majority of satellites in orbit, I highly recommend looking at it, fascinating stuff. ",
"For a scintillating read a few times a year, I recommend [Orbital Debris Quarterly](_URL_0_).\n\nIn brief summary -- yes, it is a significant problem, and the US government spends significant resources tracking as much debris as possible, partly in order to be able to move spacecraft out of the way when the situation looks dicey. Nevertheless, pieces of debris have struck spacecraft both manned and unmanned -- here is an example of what a tiny paint chip did to a space shuttle window: _URL_1_ . And a couple of major incidents -- including one collision between two satellites and a couple of anti-satellite launches -- have created big clouds that can pose elevated threats for months or years afterward.\n\nHowever, it is important to note that the specific scenario in *Gravity* is an exaggeration. Even if there were a big cascade of collisions, it would take a lot longer than 10 minutes to snowball out of control. ",
"In short, it's a serious problem. Fortunately, NASA tracks everything in orbit bigger than about 3\". This allows us to plan trajectories so we don't launch into stuff. Also, solar storms increases pressure causing the junk to fall into a lower orbit and eventually burn out coming into the atmosphere. Unfortunately, after a storm, NASA has to find all the junk again which is when it's a very serious problem.",
"On a related note, is the problem that we're launching things in opposite directions? A satellite heading west at 17,00 mph and one headed east at 17,000 mph would make a pretty big crash. If we always launched everything east, wouldn't everything be around 17,000 mph and so not be as much of a problem because their relative speeds aren't that far off? Or would they still vary by a few thousand mph--is that enough for a paint speck to crack the window?",
"Its pretty bad, as other people here have said. I wanted to mention the Kessler Syndrome though. _URL_0_ while we are not quite to this point yet we need to do something soon or risk putting ourselves in a situation cut off from space entirely. ",
"I can't actually find atmospheric drag mentioned in the top comments, so I feel like I should do that here.\n\nSpace junk is self-cleaning within certain regions over certain time frames. If a satellite is placed in a sufficiently *low* orbit, then it will naturally deorbit and probably burn up in the atmosphere. It also depends on the size. Extremely tiny debris will be cleared a lot faster - so it's a function of those two variables.\n\nBut high enough up, there is virtually no natural clearing, or at least not for our lifetimes. In geosynchronous orbits, which are extremely high, they'll virtually never re-enter for our purposes. The real trouble spots, however, isn't GEO or very low orbits. It's Low Earth Orbit, but high enough for the tiny stuff to stick around.\n\nWorst case scenario, we might get something like a \"no man's land\" of altitudes where we *mostly* avoid due to the hazard. But if we can prevent large collisions with sustainability programs, we might see the debris hazard actually get *better* in our lifetimes due to the natural clearing. That's why it's important to address."
]
}
|
[] |
[] |
[
[
"http://science.nasa.gov/realtime/jtrack/3d/JTrack3D.html/"
],
[
"http://orbitaldebris.jsc.nasa.gov/newsletter/newsletter.html",
"https://student.societyforscience.org/sites/student.societyforscience.org/files/main/articles/a1759_2889.jpg"
],
[],
[],
[
"https://en.wikipedia.org/wiki/Kessler_syndrome"
],
[]
] |
|
4bzkt3
|
Theoretically, how many bits of information make up our universe?
|
I was wondering about this in relation to a simulation. If there was a simulation on the scale of our universe, something as complex and as large, in terms of actual bits, how many would this simulation have/need? I dont know if this is the proper way to put this question, but hopefully someone understand. Is this is even possible to estimate? Thanks!
|
askscience
|
https://www.reddit.com/r/askscience/comments/4bzkt3/theoretically_how_many_bits_of_information_make/
|
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"A huge fraction of the information of the observable Universe is in black holes, ironically since we don't know how that information is encoded. It's around 10^(100) bits. Without black holes it's around 10^(90) bits, and almost all due to the CMB.\n\nThere is an upper bound suggested by holography (Bekenstein) that, assuming it is applicable, sets a theoretical limit at 10^(123) bits. The idea is if the bulk of the observable Universe is holographically dual to a theory on the boundary, the info must be bounded by something on the order of the boundary's area in Planck units"
]
}
|
[] |
[] |
[
[]
] |
|
9ji37k
|
how scientists landed a probe on a moving asteroid?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9ji37k/eli5_how_scientists_landed_a_probe_on_a_moving/
|
{
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"Lots of math.\n\nThings in space move in predictable paths. If you have a good understanding of the solar system (which we do) you can very accurately predict where things will be and how fast they will be going very far into the future. Then you just need to have your probe be at the right place, and moving at the right speed to make a rendezvous. ",
"Science has gotten very good at approach trajectories.\n\nCalculating the known location and trajectory of the target object, they use math to determine the best speed and direction required to send the probe so that it arrives near the asteroid at a proper relative speed to allow landing. Then, using maneuvering thrusters and some more math, they land the probe on the asteroid."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1rgkpc
|
Why was Israel not prevented from obtaining the bomb in the same way Iran was?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1rgkpc/why_was_israel_not_prevented_from_obtaining_the/
|
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"One answer that absolutely does not get to the heart of the matter, but is worth mentioning, is that Israel is not a signatory of the Nuclear Non-Proliferation Treaty (neither are India, Pakistan, and North Korea). \n\nAnother answer is that Iran has not been prevented from obtaining a bomb. Nor has been North Korea, nor India, nor Pakistan. China got the bomb while they were not even recognized as a legitimate government. South Africa got it, and Brazil came very close (and both countries gave up their weapons program voluntarily). ",
"Isreal aquired large amounts of nuclear technology and materials from [France in the mid-1950s](_URL_0_), in exchange for military support for France's campaigns in North Africa (Algeria and Suez Canal). The participants were quite successful in keeping the arrangement a secret until well after Isreal had accumulated a significant number of nuclear weapons. In fact, Isreal was not confirmed to possess nuclear weapons until 1986 (although it was basically an open secret since the 1970s).\n\nThe Nuclear Non-proliferation Treaty was put forth in 1968 and went into effect in 1970, a decade and a half after Isreal had already aquired the technology. Isreal never signed the treaty, but Iran did ratify it in 1968.\n\nIran's development of nuclear weapons is therefore seen as a treaty violation, hence the global condemnation.\n",
"As said, Israel got quite a huge amount of help from France in the 50s (France was very pro-Israel till at least the end of the 50s). \nWhen the NPT went into effect, Israel was probably already in possession of a nuclear weapon. \n\nAnother interesting point is that, although several countries do have nuclear weapons (US, Russia, China, France, GB, India, Pakistan, Israel and NK), they are not the only ones with the capacity to build these weapons. \nSouth Africa destroyed their bombs (they had maybe half a dozen) in the 90s. Iraq, Switzerland, Sweden, have worked on obtaining these for sure, and maybe Brasil, Argentina, Syria, Taiwan and Lybia too. \nUkraine, Belarus and Kazakhstan, when the URSS disappeared, had atomic weapons on their soil. They choosed to surrender these weapons to Russia, but at least the first two would have had the technological level and infrastructure to maintain their weapons. \nToday, at least a dozen countries could build nuclear weapons \"easily\" : Canada, Germany, Japan, South Korea, Australia, Brasil, South Africa, Sweden, Switzerland; maybe Belgium, Spain, Poland, Mexico, Argentina. They don't because they don't feel the need to: it costs a lot, it is diplomatically not a good move to acquire in the current circumstances, and it is a weapons not to be used but to be had (which is not really usefull if you don't find someone to threaten with)."
]
}
|
[] |
[] |
[
[],
[
"http://www.telegraph.co.uk/news/worldnews/middleeast/israel/1366164/Israel-reveals-secrets-of-how-it-gained-bomb.html"
],
[]
] |
||
nlsgf
|
Would scientifically advanced ET's be able to detect
nuclear explosions from distant planets? ie send
strong signal of some wave/form.
|
askscience
|
http://www.reddit.com/r/askscience/comments/nlsgf/would_scientifically_advanced_ets_be_able_to/
|
{
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"Not likely. The EM radiation given off by nuclear explosions is largely absorbed by our atmosphere in much the same way that our atmosphere protects us from harmful EM radiation coming from the sun. What little radiation that did escape the Earth would probably just be overlooked as background noise if it were detected at all. ",
"Not likely. The EM radiation given off by nuclear explosions is largely absorbed by our atmosphere in much the same way that our atmosphere protects us from harmful EM radiation coming from the sun. What little radiation that did escape the Earth would probably just be overlooked as background noise if it were detected at all. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
20ue5p
|
When the Universe reaches heat death, at absolute zero, do atoms remain intact, or do they degrade into elementary particles?
|
I'm sorry if the question is a bit unclear; my boyfriend and I were having an argument last night on whether or not, when the Universe reaches heat death, matter still exists as atoms, or do those atoms degrade into elementary particles?
In short, could I theoretically detect atoms of matter, or, does the strong nuclear force stop working at absolute zero and those atoms degrade into neutrons, protons and electrons?
Edit : corrected strong magnetic force to strong nuclear force.
|
askscience
|
http://www.reddit.com/r/askscience/comments/20ue5p/when_the_universe_reaches_heat_death_at_absolute/
|
{
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"text": [
"Though there is no experimental evidence, there are a lot of theories which suggest that protons can eventually decay. As neutrons decay after about 15 minutes outside of an atomic nucleus, this would mean that all atomic matter would eventually decay.\nAt the same time, the Standard Model (which is the dominant theory in particle physics, it predicted the Higg's Boson) states that protons are stable, and will not decay.\nAlso, finding out whether or not a nucleus is stable or not is a game of staring at it and waiting to see if it decays, bismuth 209 was recently found to have a finite lifetime after previously being thought to be stable.\n\nBy the way, the force that keeps nuclei together is called the strong nuclear force, it's not related to magnetism."
]
}
|
[] |
[] |
[
[]
] |
|
lqun0
|
What, exactly, makes an orbit stable or unstable?
|
I'm familiar with the basic, super simple model of orbit with Kepler's laws and Newtonian gravity. In that context, everything either orbits, crashes, or flies away.
In reality, are there other cases? Can an orbit be more or less stable at one point in time and unstable sometime later with no direct adjustment to its trajectory?
Also, I'm aware this is a completely separate question, but what exactly is the mechanism for how the moon reduces the axial tilt/procession of the earth?
|
askscience
|
http://www.reddit.com/r/askscience/comments/lqun0/what_exactly_makes_an_orbit_stable_or_unstable/
|
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"In reality, there are always external forces that act on orbiting bodies.\n\n* Atmospheric resistance for close orbits\n* Solar wind / Solar light presure\n* Effects of other bodies in the solar system (very slight, but still present)\n\nFor the second question, in the ideal mathematical case, the moon's orbit should be stable and constant. In reality, it's not, as we know it's orbit is expanding. I understand this is caused due to the moon's effect of slowing down the Earth's rotation. That transfers energy from the moon's orbit to the Earth momentum. If this eventually results in Earth being tide-locked with the moon, at which time, that transfer would stop.",
"from pure mechanical point of view, you can get unstable orbit only in relativistic mechanics and only very close to the center of gravity (close to the event horizon).\n\nin newtonian gravity, you always get some kind of orbit. the sum of potential and kinetic energy is constant. if you have more potential energy than kinetic energy, you get eliptical orbit. if you have more kinetic energy than potential energy, you can fly to infinity over hyperbolic orbit (i.e. even if you move to infinity, you still have some kinetic energy left). parabolic orbit is what you get when the potential energy is exactly equal to kinetic.\n\nin newton mechanics you cannot crash to a mass point that you are orbiting unless you go straight down on it. that is because the gravitational potential goes to infinity as you get close. so when you come closer, your speed increases and in the end you start going further. the resulting behaviour is as described above.\n\nin relativistic mechanics you can only write something that's called \"effective potential\" (google it up, add \"relativistic\" for more info). and that potential looks quite similar to the classical newton potential when you are far enough, but it is very different when you are close. under certain radius you simply cannot have any value of potential energy to stay in orbit. you either don't have enough kinetic energy and move towards gravitational center until you go under event horizon, where the time and radial coordinates swap and going forward in time means going towards center, or you can have enough kinetic energy just above the event horizont and at the same time move away from the center and escape to infinity.",
" > I'm familiar with the basic, super simple model of orbit with Kepler's laws and Newtonian gravity. In that context, everything either orbits, crashes, or flies away.\n\nThis is only true in the context of a two body system. When more than 2 bodies are present, the system becomes chaotic and eventually unstable. So it isn't a question of stable vs. unstable, it is a question of stable *enough* to stick around for a stellar lifetime.\n\nOrbits are stable until they are not. Mars's moon Phobos, for example, has an \"unstable\" orbit around Mars. Due to tidal friction, it is slowly getting closer to Mars, and will eventually be ripped apart to form ring system. But that won't happen for another 8 million years...for now, the orbit is \"stable\".",
"In reality, there are always external forces that act on orbiting bodies.\n\n* Atmospheric resistance for close orbits\n* Solar wind / Solar light presure\n* Effects of other bodies in the solar system (very slight, but still present)\n\nFor the second question, in the ideal mathematical case, the moon's orbit should be stable and constant. In reality, it's not, as we know it's orbit is expanding. I understand this is caused due to the moon's effect of slowing down the Earth's rotation. That transfers energy from the moon's orbit to the Earth momentum. If this eventually results in Earth being tide-locked with the moon, at which time, that transfer would stop.",
"from pure mechanical point of view, you can get unstable orbit only in relativistic mechanics and only very close to the center of gravity (close to the event horizon).\n\nin newtonian gravity, you always get some kind of orbit. the sum of potential and kinetic energy is constant. if you have more potential energy than kinetic energy, you get eliptical orbit. if you have more kinetic energy than potential energy, you can fly to infinity over hyperbolic orbit (i.e. even if you move to infinity, you still have some kinetic energy left). parabolic orbit is what you get when the potential energy is exactly equal to kinetic.\n\nin newton mechanics you cannot crash to a mass point that you are orbiting unless you go straight down on it. that is because the gravitational potential goes to infinity as you get close. so when you come closer, your speed increases and in the end you start going further. the resulting behaviour is as described above.\n\nin relativistic mechanics you can only write something that's called \"effective potential\" (google it up, add \"relativistic\" for more info). and that potential looks quite similar to the classical newton potential when you are far enough, but it is very different when you are close. under certain radius you simply cannot have any value of potential energy to stay in orbit. you either don't have enough kinetic energy and move towards gravitational center until you go under event horizon, where the time and radial coordinates swap and going forward in time means going towards center, or you can have enough kinetic energy just above the event horizont and at the same time move away from the center and escape to infinity.",
" > I'm familiar with the basic, super simple model of orbit with Kepler's laws and Newtonian gravity. In that context, everything either orbits, crashes, or flies away.\n\nThis is only true in the context of a two body system. When more than 2 bodies are present, the system becomes chaotic and eventually unstable. So it isn't a question of stable vs. unstable, it is a question of stable *enough* to stick around for a stellar lifetime.\n\nOrbits are stable until they are not. Mars's moon Phobos, for example, has an \"unstable\" orbit around Mars. Due to tidal friction, it is slowly getting closer to Mars, and will eventually be ripped apart to form ring system. But that won't happen for another 8 million years...for now, the orbit is \"stable\"."
]
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|
[] |
[] |
[
[],
[],
[],
[],
[],
[]
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|
3bdwc1
|
how do some insects fly so sporadically and change direction so quickly? how many g's are they under during maneuvers like that?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3bdwc1/eli5_how_do_some_insects_fly_so_sporadically_and/
|
{
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"What a cool question. \n \nTo start, most people could probably withstand around 9 Gs for a very short time. Then they would pass out and possibly suffer brain damage. The highest G-force ever put into a roller-coaster was around 6 Gs, but most very high G coasters are somewhere in the neighborhood of 4 Gs. \n\nSo, \n \nFleas can jump about three inches into the air. Which is around 40 times the length of their body, and they do that in around 1/1000 sec. They pull more than 100 Gs in that maneuver. \n \nDragonflies can see 360° and can execute a hairpin turn at 100 Kph. They're pulling around 25 Gs in that turn. \n \nJumping froghoppers and click beetles are probably the masters here though. A fly being knocked out of the sky by a swatter is taking around 200 Gs and that kills it. So we generally think of that as lethal for insects. Froghoppers catapult themselves about 28 inches into the air. That's about 1400 times the length of their body and in doing this they pull 400 Gs. \n \nClick beetles will generally match the froghopper. But one individual was calculated to have pulled peak brain deceleration of around 2300 Gs. in a leap. \n \nSo they can really move. ",
" > How do some insects fly so sporadically and change direction so quickly?\n\ninsects' small size make them much more subject to things like viscous forces which radically alters their aerodynamic properties. they don't even fly using conventional lift mechanics. instead, they fly though the generation of small vortices (think smoke rings). \n\n > How many g's are they under during maneuvers like that?\n\nthat's... actually fairly difficult to answer. acceleration is just change in velocity over time, but studying it for a fly would be quite the feat, I would imagine it's quite high. the reason insects can do things like spring several times their body length in a fraction of a second is because of how small they are. due to their low mass, the forces they experience (force is just mass times acceleration) are fairly low."
]
}
|
[] |
[] |
[
[],
[]
] |
||
3v9kzh
|
Is there an important battle that was basically settled in favor of the disadvantaged party (fewer men, resources, tech etc.) by the occurrence of a natural disaster?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3v9kzh/is_there_an_important_battle_that_was_basically/
|
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"I would not call it a natural disaster but the Winter of 1941/1942 was particularly cold (Also the Winters of 1939/1940 and 1940/1941 were considered to be extreme.). Probably even one of the coldest, if not so the coldest, Winter of the 20th century. Some historians argue it influenced the outcome of Operation Barbarossa.\n\n------\nI want to make clear that I don't state that Germany lost the war, or even this campaign, because of the extreme Winter. As Historian David Stahel [And Adam Zamoyski Regarding Napoleon] has stated: \n\n > *\"The belief that 'General Mud' and 'General Winter' were the real culprits behind the 1941 failure of the Barbarossa campaign, is still commonly heard and even published today. Interestingly, in the wake of Napoloen's failed 1812 invasion of Russia, the French also took solace from the myth that they had been defeated by the Russian winter, rather than the Russians themselves or Napoleon's own mistakes.\"*\n\nStahel, in my opinion correctly, thinks this is a result of a wrong methodology and the lack of information from the Russian side [furthermore in the Cold War era it was not always common practice to give the Red Army a lot of credit]. Also the idea that Adolf Hitler was an 'evil genius' who could not make mistakes was very much present after the war. It would be better to see the extreme Winters as a force underlining the failures that were already present in the German hierarchy and structures. The problems German faced became more visible as a result of the extreme Winter but was not necessarily the consequence of it.\n\nDespite this short nuance I would like to mention this Winter because it did influence German operations, but be aware, this is something clearly different from stating that Operation Barbarossa was lost by the Germans because of the winter. It is an important part before reading further and I think a similar analysis can be made for Napoleon's campaign in Russia.\n\n------\n\nThe Nazi's have underestimated the strength of the Winter. German Weather Forecasters convinced Hitler that the Winter following Operation Barbarossa would be mild. Furthermore they thought that they would have reached their main targets before the extremities of this season would set in. This is why the necessary clothing was not available for the Wehrmacht in Russia for a long time. Also theories exist that claim it was the result of Hitler's madness who personally underestimated Russia's winter and thought coldness was something to be overcome with a strong mentality. Although material does exist that Hitler did say these kind of things the accusation itself can be a forgery from military leaders trying to clear their name after World War II. \n\nRegardless it is true that Hitler dismissed later warnings by weather experts and military leaders. He referred to weather forecasts stating that the extremities of Winter would Russia's South before the area around Moscow which he claimed would have a rainy character. This led to his decision to attack Kiev before Moscow and he dismissed all reports and statements of experts trying to convince him to act different. Operation Typhoon aimed for Moscow. The first period everything was fine and there were no problems with the weather. General Zhukov worried at this time if Moscow could even defended while the German General Staff already proclaimed victory. However, at the start of October when Hitler predicted rain, it started to snow. This clearly affected the German motorized units.\n\nHeinz Guderian:\n\n > *\"The first snow of the winter fell. It did not lie for long and, as usual, the roads rapidly became nothing but canals of bottomless mud, along which our vehicles could advance only at snail‘s pace and with great wear to the engines. The next few weeks were dominated by the mud. Wheeled vehicles could only advance with the help of tracked vehicles. These latter, having to perform tasks for which they were not intended, rapidly wore out. Preparations made for the winter were utterly inadequate.\"*\n\nOr as a German soldier wrote in 1941:\n\n > *\"Technology no longer plays a role. The elemntal power of nature broke the operations of our engines. What do we do?\"*\n\nThis did not only happen at Moscow but also near Leningrad and ofc Stalingrad. The German offensive stopped and the military staff had to abandon the offensive for a while. The problem was not only that there was not enough material. The heavy snow also prevented German trains and sometimes even planes to come close to the German troops. The Russian road network was often the only way of transportation that could be used. This were aged roads which already had difficulties to transport the huge German armies in better temperatures. The coldness still prevented motorized vehicles to use the roads often. Horses had to be used and other forms of transport. Food, clothing, and other necessary survival material could often not be delivered. The encirclement of these cities became very hard, lines were difficult to defend and to supply, soldiers often literally froze to death at the front.\n\nJoseph Goebels proclaimed in 1941 with an attempt to send more material to the troops in the extremely cold area's:\n\n > *\"Those at home will not deserve a single peaceful hour if even one soldier is exposed to the rigours of winter without adequate clothing.\"*\n\nWinston Churchill said around the same time: \n\n > *\"There is a winter, you know, in Russia. For a good many months the temperature is apt to fall very low. There is snow, there is frost, and all that. Hitler forgot about this Russian winter. He must have been very loosely educated. We all heard about it at school; but he forgot it. I have never made such a bad mistake as that.\"*\n\nComing from the man who planned Gallipoli this is quite an insult.\n\nThe consequences of this Winter cannot be underestimated. We are not simply talking about soldiers freezing to death, estimated to be hundreds of thousands, but countless of wounded Germans without limbs, who were not able to find any food on the frozen Russian grounds, and mental effects. Organization failures, hierarchical problems, and a lack of sufficient preparation, these underlying problems were all even more visible and problematic because of the extreme Russian winter. The German army was not capable to come up with practical solutions because of bad preparation and estimation. The Russians were way more capable to make use of these circumstances and benefited from the German failures.\n\nIn short the reason that Operation Barbarossa was a failure has many more reasons some even more important probably then the Russian Winter. It would be better to state that the extremities of the Winter strengthened the actual reasons Germans lost this campaign. Organizational failures, underestimations of the operation itself, and a lack of a well organized preparation became more visible as a result of the Russian Winter in this area.\n\nThe underestimation of the Russian armies and the underestimation of the Russian capabilities to reorganize are also important examples.\n\n* Andrew Roberts - The Storm of War\n* Alfred W. Turney - Disaster at Moscow\n* David Stahel - Operation Barbarossa and Germany's Defeat in the East\n\n\n\n",
"Responding to /u/EbenSquid 's [~~bat~~ flair-signal](_URL_2_).\n\nIt was widely believed by all sides that if the Spanish had been able to land sufficient troops on English soil, then the coming war would be as good as done. English soldiers consisted mainly of untrained militia, lacking equipment, training, experience, leadership, and most importantly the new style of fortification. Grand plans [were made](_URL_1_).\n\nSeveral ideas for the Spanish enterprise, as it was called, were proposed. One is to mount an attack from Spain to land soldiers either in England itself or in Ireland first. Second is to mount a diversionary naval assault while troops from Flanders sail across in smaller vessels. Another is to do all of the above at once. In the end, Philip II settled for perhaps the most complicated sequential plan. \n\n[So, what really happened then?](_URL_0_)\n\nOn their way to meet the Spanish Army of Flanders in Dunkirk, a combination of harassment by English vessels and bad weather scattered the Spanish. On their way back to Spain, many vessels were lost in inclement weather, as they took the long way back (across the north of Scotland).\n\nIf more vessels had survived, Philip II may have re-mounted another enterprise, but the huge loss meant several things happened. First is that Philip II had to dig deeper into debt to replace the losses, beyond sustainable level. Second is the loss of expert sailors and commanders. Third is that he was forced into the defensive everywhere, as the English navy now had the advantage. \n\nWhat didn't happen was the eventual domination of the English navy. That had to wait until much later, after the Anglo-Dutch war. But suffice to say, weather played a major role in the failure of the Armada. ",
"There are debates on whether the Japanese defenders at Kyushu could have held back against the Mongol Invasion by themselves.\n\nBut the two Kamikaze typhoons definitely helped by sinking the majority of the invasion fleet.",
"The firtst Mongol invasion of Japan was thwarted by a typhoon. The Mongols had landed in North Kyushu with around 23,000 troops. They initially made quick work of the inexperienced Japanese, but in the night a typhoon hit and the Mongols retreated so as to avoid being marooned.\n\nIn the process they lost most of their larger ships and many of the rest were picked off by Japanese boarding parties coming from smaller, more manoeuvreable boats.",
"Confederate General John Hunt Moran's Great Cavalry Raid through Indiana and Ohio was a fairly solid success up until the Battle of Buffington Island in Meigs County, Ohio. Over several weeks Morgan's men had swept through Indiana and Ohio causing mayhem and diverting Burnsides' Union Forces away from the front in Tennessee. \n\nWhile it is an often overlooked moment in the war, it had the potential to create some major change. At one point there were 65,000 Union forces and militia chasing Morgan's few thousand raiders through Indiana, and additional 60,000 men end up chasing him through Ohio. \n\nMorgan's goal was to eventually cross the Ohio river back into Virginia. Unfortunately most of the fords were blocked, so he kept going across the entire state of Ohio. Finally, he ended up in Meigs County in the far Southeastern section of the state and made an attempt to cross the ford at Buffington Island. \n\nMorgan's men fought through a gauntlet of local militia, with the regular Union forces in his rear by a few hours, until he finally reached the fords after dark. When he got there he found militia from nearby Marietta entrenched at the entrance of the ford. It was a small number, but because of the darkness Morgan couldn't get an accurate estimate on their strength, so he chose to camp rather than cross at night.\n\nWhile the Union Army had a statistical advantage in numbers, up until this point Morgan's Raid was a resounding success - all he had to do was cross the river and he was home free on Confederate soil and would return a hero. Unfortunately for him he had no idea that a huge storm system had been dumping rain in Pennsylvania for days and a huge wall of water was making it's way straight for the ford. When his men awoke the next morning they found the river almost completely impassable.\n\nIt just so happened that a dense fog had also come up the river bottom and while some of Morgan's men were advancing down the road they basically ran into the Union forces. The battle of Buffington Island ensued and Morgan and his forces were scattered. \n\nSome of the Confederate Cavalry had actually attempted and succeeded in crossing the river right before the battle started, but they couldn't get back across the river. They watched helplessly from the Virginia cliffs as their friends were slaughtered.\n\nMorgan and several hundred of his men escaped and continued to make their way north, all the while looking for another spot to pass, but they were eventually in Northeast Ohio. Morgan was imprisoned at the Ohio State Penitentiary (because the Union Army considered him more of a criminal than a soldier), but eventually escaped and made his way back to the South where he was eventually killed in Tennessee.\n\nMorgan's Raid and General Morgan himself are both absolutely fascinating pieces of the Civil War. I highly recommend David Mowery's book \"Morgan's Great Read\" if you're interested in learning more about one of the more amazing stories of the Civil War."
]
}
|
[] |
[] |
[
[],
[
"https://www.reddit.com/r/AskHistorians/comments/1gy78o/what_really_happened_to_the_spanish_armada/",
"https://www.reddit.com/r/AskHistorians/comments/38nhow/what_was_philip_iis_plan_for_england_had_the/cs4ktsu",
"https://www.reddit.com/r/AskHistorians/comments/3v9kzh/is_there_an_important_battle_that_was_basically/cxln6hz"
],
[],
[],
[]
] |
||
480atf
|
the passage of time while sleeping.
|
It seriously confuses me so much. Time just goes so quickly while sleeping. I remember once as a child I was trying to fall asleep and I blinked while looking at my clock and it was suddenly morning.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/480atf/eli5_the_passage_of_time_while_sleeping/
|
{
"a_id": [
"d0gmn9m"
],
"score": [
5
],
"text": [
"The passage of time is nothing more than our ability to remember events during that time. You don't remember anything while sleeping save for a few moments dreaming.\n\nSet up your web cam and record a video. Put a clock in the background to show the passage of time. Pause recording for a bit then resume recording. Watch the video later as this video is your memory. At some point the video will jump ahead. This gap where the recording skipped is like you sleeping."
]
}
|
[] |
[] |
[
[]
] |
|
cpyrks
|
why do strong weather systems break up around nuclear power plants?
|
I live within 10 miles of a nuclear power plant and whenever a strong weather system comes through, if you watch the radar, the red/strongest part will break up and go around the nuclear plant as it approaches. After it passes, it goes right back to how it was before it approached the plant.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/cpyrks/eli5_why_do_strong_weather_systems_break_up/
|
{
"a_id": [
"ewsi65g"
],
"score": [
7
],
"text": [
"We don't have a Nuclear power plant near us, but we do have a decent sized steam plant, and it seems like the strong stuff is always going around then reforms"
]
}
|
[] |
[] |
[
[]
] |
|
1z4nqv
|
What makes the "physics is cool" photo possible?
|
For those of you who haven't seen it: _URL_0_
|
askscience
|
http://www.reddit.com/r/askscience/comments/1z4nqv/what_makes_the_physics_is_cool_photo_possible/
|
{
"a_id": [
"cfqq6bi"
],
"score": [
3
],
"text": [
"Basically, it works like this: the water *should* be moving upward - if the plane and everything around it suddenly vanished, the water would have an upward velocity. But the plane (and the pilot, and the cup) is accelerating downward faster than gravity, so the water gets driven upward into the cup. The acceleration downward of the plane is *larger* than the acceleration the water would experience in freefall."
]
}
|
[] |
[
"http://redd.it/1z3spe"
] |
[
[]
] |
|
gghor
|
Why is Planck time a measure of the Planck length divided by a factor of c^5 and not c?
|
I was watching [sixty symbols](_URL_1_) and they discussed Planck time. I was looking at the [wikipedia](_URL_0_) page and saw c^5. The video made is seems as if you only need to divide by c. It may just be some complex math or there may be a reason for it, either way I am curious.
|
askscience
|
http://www.reddit.com/r/askscience/comments/gghor/why_is_planck_time_a_measure_of_the_planck_length/
|
{
"a_id": [
"c1nczlf"
],
"score": [
7
],
"text": [
"The Planck time *is* the Planck length over c. Planck length is sqrt( hbar * G / c^3 ), and as you saw Planck time is sqrt( hbar * G / c^5 )."
]
}
|
[] |
[
"http://en.wikipedia.org/wiki/Planck_time",
"http://www.youtube.com/watch?v=zPgtPF0kduA&feature=feedu"
] |
[
[]
] |
|
joqaz
|
What's the difference between an electron and a black hole of the same mass, spin, charge etc.?
|
Would it ever be possible for something like that to be created? It would almost instantly evaporate due to Hawking radiation (assuming that exists), right?
|
askscience
|
http://www.reddit.com/r/askscience/comments/joqaz/whats_the_difference_between_an_electron_and_a/
|
{
"a_id": [
"c2dv9if",
"c2dx9t8",
"c2dv9if",
"c2dx9t8"
],
"score": [
2,
2,
2,
2
],
"text": [
"A hypothetical black hole with the effective mass of a single electron is a paradoxical object. It would have an entropic temperature of 10^53 degrees absolute, or 10^43 times its own intrinsic energy. Meaning it would radiate more energy than exists in the gravitational field around it.",
"A black hole of the same mass and charge can't exist. The effective mass due to the charge of the electron is actually larger than the observed mass of the electron. To describe this situation with a black hole would require an \"[overextreme](_URL_0_)\" [Reissner-Nordström black hole](_URL_1_). The spin just makes it worse...\n\nSee also _URL_2_ for more nonsense.",
"A hypothetical black hole with the effective mass of a single electron is a paradoxical object. It would have an entropic temperature of 10^53 degrees absolute, or 10^43 times its own intrinsic energy. Meaning it would radiate more energy than exists in the gravitational field around it.",
"A black hole of the same mass and charge can't exist. The effective mass due to the charge of the electron is actually larger than the observed mass of the electron. To describe this situation with a black hole would require an \"[overextreme](_URL_0_)\" [Reissner-Nordström black hole](_URL_1_). The spin just makes it worse...\n\nSee also _URL_2_ for more nonsense."
]
}
|
[] |
[] |
[
[],
[
"http://en.wikipedia.org/wiki/Extremal_black_hole",
"http://en.wikipedia.org/wiki/Reissner%E2%80%93Nordstr%C3%B6m_metric",
"http://en.wikipedia.org/wiki/Black_hole_electron"
],
[],
[
"http://en.wikipedia.org/wiki/Extremal_black_hole",
"http://en.wikipedia.org/wiki/Reissner%E2%80%93Nordstr%C3%B6m_metric",
"http://en.wikipedia.org/wiki/Black_hole_electron"
]
] |
|
33fnm3
|
What was the reaction to Washington freeing his slaves when he died?
|
How did Jefferson and other political figures react to him freeing his slaves? Also, how did Virginians react to it?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/33fnm3/what_was_the_reaction_to_washington_freeing_his/
|
{
"a_id": [
"cqkvanp"
],
"score": [
2
],
"text": [
"George Washington owned several slaves outright, but most belonged to the Custiss estate. He legally wasn't allowed to free them. We can speculate that Washington could've gotten away with freeing the slaves owned by his first wife's husband as he was very well respected and admired. But he was very concerned with precedent. So we can also speculate that. But it is *only* speculation. \n \nBut Martha freed many of them after her husband's death because of a series of fires that seemed to be intentional. The slaves would be freed upon her death, but she was aware that there were several people who were waiting for her to die, so she sped up the process.\n\n\nSource: _URL_0_\n\n"
]
}
|
[] |
[] |
[
[
"http://www.mountvernon.org/george-washington/martha-washington/martha-washington-slavery/"
]
] |
|
l8ow4
|
Why are laws of physics absolute?
|
I'm only asking this question from a ignorant stand point of view. I usually hear a normal discussion on tv, radio or even in life, and it goes something like this:
Person A: "Dude, that new spaceship can travel faster then the speed of light." (Sorry can't think of a great example right now)
Person B: "Dude, that goes against the laws of physics/thermodynamics/etc."
It's my understanding that the "Laws of Physics" are a conclusion drawn from what we have observed and tested in our little corner of the galaxy. How are we so certain that these laws apply to the whole universe? And why isn't this same principle applied to evolution on our planet? I mean we have so much evidence and date yet it is still called "theory." Why can't it become an absolute fact?
|
askscience
|
http://www.reddit.com/r/askscience/comments/l8ow4/why_are_laws_of_physics_absolute/
|
{
"a_id": [
"c2qp21g",
"c2qp21g"
],
"score": [
2,
2
],
"text": [
"We just call it a law because so far, all the evidence we have support them. So, we are not certain that they apply to the whole universe but you can't just make a random claim that is not supported by any evidence or is impossible to test. \n\nAs for evolution, a lot of the naming is political, but it does indeed have plenty of evidence backing it up.",
"We just call it a law because so far, all the evidence we have support them. So, we are not certain that they apply to the whole universe but you can't just make a random claim that is not supported by any evidence or is impossible to test. \n\nAs for evolution, a lot of the naming is political, but it does indeed have plenty of evidence backing it up."
]
}
|
[] |
[] |
[
[],
[]
] |
|
2sge9z
|
Does arousal and bodily changes cause emotion or is it the other way around?
|
I understand the James-Lange theory but I don't get why it works. How would we be able to have emotion without first consciously thinking about the situation causing emotion. How does our body know to do an involuntary action such as cry from something human made like verbal insults? To me the Cannon-Bard theory makes more sense, where the emotion comes first and that causes a change in the body, but most people seem to accept the James-Lange.
|
askscience
|
http://www.reddit.com/r/askscience/comments/2sge9z/does_arousal_and_bodily_changes_cause_emotion_or/
|
{
"a_id": [
"cnpa868"
],
"score": [
3
],
"text": [
"First of all, both of these theories are huge oversimplifications of emotion generation (e.g., they depict emotion generation as a linear sequence, when it's likely much more complicated). \n\n > How would we be able to have emotion without first consciously thinking about the situation causing emotion. How does our body know to do an involuntary action such as cry from something human made like verbal insults? \n\nWhat's missing from the James-Lange theory is the meaning making, or conceptualization, process (e.g., Barrett, 2014). If your heart beats fast as you run from a bear, you might feel fear. If your heart beats fast as you are confronted with an unexpected birthday party, you might feel surprised. In both instances, the physiological change is the same, but the emotion and context is different.\n\nWhat's happening then is that you are constructing your emotional experience by making your increased heart rate psychologically meaningful. In the first instance, your heart rate is meaningful because a bear is chasing you; thus, you feel fear. In the second instance, your heart rate is meaningful because you're at a surprise party; thus, you feel surprise. \n\nThis process of meaning making and conceptualization you do automatically and continuously (Barrett, Wilson-Mendenhall, & Barsalou, 2014). Prior experience (with things chasing you, unexpected events, etc.) also shapes how you process and respond to sensory input in the moment (automatically). \n\nNote, however, that just because you experience a physiological change does not mean that you will experience an emotion. Physiological changes in your body are constantly occurring, yet you don't constantly report feeling an emotion. The missing ingredient here is *attention*. Only when you attend to (are foregrounding) your intense physiological sensations (e.g., a faster heart beat)--which you might do automatically because this has been useful in past situations (e.g., when encountering something dangerous)--will you feel fear or surprise (etc.). \n\nIn other words, emotions occur when \"a shift in core affect [arousal and valence] is at the forefront of attention and made meaningful using exteroceptive sensations and conceptualizations\" (Oosterwijk, Touroutoglou, & Lindquist, 2014).\n"
]
}
|
[] |
[] |
[
[]
] |
|
7b4j47
|
why underwater lighting illuminates objects underwater much better than objects above water
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7b4j47/eli5_why_underwater_lighting_illuminates_objects/
|
{
"a_id": [
"dpf747s",
"dpfa7sm"
],
"score": [
6,
2
],
"text": [
"It’s called total internal reflection, basically the light is reflecting off the internal side of the surface of the water. \nBasically the same way fibre optics work ",
"Light bounces around under the water, and hits more things. Less light makes it out of the water to illuminate things after refraction/reflection etc."
]
}
|
[] |
[] |
[
[],
[]
] |
||
fpl9ys
|
why does there need to be a separate wash process for cleaning a dishwasher? why doesn’t it clean itself during a normal cycle?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/fpl9ys/eli5_why_does_there_need_to_be_a_separate_wash/
|
{
"a_id": [
"flll72v",
"flllx7v",
"fllm0sd"
],
"score": [
7,
3,
12
],
"text": [
"The soaps used to clean dishes can build up after many wash cycles. The dishwasher is then cleaned with a soap-removing solution. You can't wash dishes all the time with that, because it doesn't take off greasy stuff like food very well, and it costs more.",
"It really depends how heavily you load your dishwasher. A dishwasher loaded with relatively clean plates may well go its whole life without a cleaning cycle and suffer no ill effects. A dishwasher used to clean heavily soiled plates regularly may need cleaning every month. \n\nWith modern dishwashers, they use very little water and run at cooler temperatures. This means the cleaning water gets very dirty and deposits can start to form over time, particularly in all sorts of hidden locations like pipes, pumps and spray arms.\n\nAn empty/light load ran on a normal cycle will clean the dishwasher, but some hard to shift deposits may be left. The special wash cycle is hotter and more intensive to give your machine a really good clean. The special cycle may not rinse and dry properly so is not appropriate for washing dishes.",
"Because people are stupid and toss the most disgustingly unrinsed crap in their dishwashers.\n\nAs such, they need a special function to get properly clean. In most units they -super- heat the water to near boiling, and this can deal with the disgusting that builds up in them.\n\nBut I've had my dishwasher for 4 years and I've never used the cleaning cycle. Its spotless inside. Because I, like many but not all sane humans, rinse or even quickly prescrub really nasty dishes."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
9ur2ql
|
How does lead get in water from pipes? Can lead be filtered out of water?
|
Can lead molecules be filtered out of drinking water?
A quick Google search revealed that, yes, it can be filtered out. If so, why haven't schools and public institutions (Flint, MI) installed filters as a temporary fix until the pipes can be replaced?
|
askscience
|
https://www.reddit.com/r/askscience/comments/9ur2ql/how_does_lead_get_in_water_from_pipes_can_lead_be/
|
{
"a_id": [
"e97bqyd",
"e99634v"
],
"score": [
4,
2
],
"text": [
"Yes, filtering lead out of water is as simple as reverse osmosis. However, lead in the water, specifically in Flint, is caused after the water is already cleaned at the water treatment plant. These impurities are a result of water travelling through old pipes and improperly treated pipes that corrode due to erosion, cold weather, and quite possibly a small reaction between added chemicals that are used to treat the water and the inner lining of the pipe (even oxidized layers of metal specifically engineered to maintain integrity will fail). Most old pipes are made of lead and in lower income areas this is often the case as they aren't maintained or cleaned as often. Moreover, there was bacterial infestation in the water in Flint due to low chlorine levels. However, in Flint, lead levels in the water were too high to be treated by any cheap water filter you could buy for your home. That's why they had to shut off the water and turn to bottled water. Moreover, Flint is a low income community and there isn't enough money or resources to install large scale water filters in public areas. Thus, they bought water from a neighboring commune and gave out bottled water",
"Lead water pipes were commonly used in the late 19th and beginning half of the 20th century. Many cities still have areas with lead pipes. Replacing all of them would be a multiple billion dollar proposition.\n\nIn areas where the surface water has high levels of carbonate, bicarbonate and sulfate ions, lead pipes aren't a problem. These ions react with the surface of the lead to form a passive layer of insoluble lead carbonates and sulfates. This prevents any lead from entering the water. This effect is known as \"passivation.\" The issue is that it's effectiveness depends on water chemistry.\n\nIn Flint, MI the issue was that the city municipal water corporation wanted to use water from the nearby Flint River. In the past they had been buying already treated water from Detroit that was sourced from lake Huron.\n\nThe problem was that Lake Huron water is hard and slightly basic. Water in the Flint River is acidic. Furthermore the Flint River has a higher level of microorganisms. \n\nState and federal standards in this situation, required the water corp to adjust the pH of the water and add corrosion inhibitors such as calcium phosphate.\n\nThe city leadership refused to pay for the extra additives, and merely added more chlorine to deal with the microorganisms. This was a violation of federal law, but the city leadership didn't give a shit and only saw a couple of extra dollars on their balance spreadsheet. They knew they were breaking the law and just covered it up, telling city residents how much money it would save the city.\n\n\nThe acidity of the new water as well as the increased chlorine began to dissolve the protective carbonate layer on historic lead pipes. This, in some cases, increased the lead content in the water by a factor of 1,000, making it unsafe for anyone downstream of lead pipes. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
5jzckw
|
if a person was standing in the north pole during the summer solstice, would the sun just appear to make a circle around the sky?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5jzckw/eli5_if_a_person_was_standing_in_the_north_pole/
|
{
"a_id": [
"dbk4c8x",
"dbkpyxx"
],
"score": [
14,
2
],
"text": [
"Yes, thats exactly what it would look like. [Here's a video from not quite so north, but in the arctic.](_URL_0_) Far enough north (or far enough south during winter solstice) the sun never sets.\n\nHaving been to northern parts of Scotland in the summer, having the sun up at 11:00pm or later can be a little unnerving. ",
"If you're exactly at the north (or south) pole then the sun always just makes circles around the sky. Around the equinoxes it will follow the horizon around; at the summer solstice it will be 23° above the horizon; at the winter solstice it will be 23° below the horizon. You only need 18° below the horizon for \"astronomical twilight\" which is roughly as dark as the sky gets. At the poles, the sun basically rises and sets once per year. "
]
}
|
[] |
[] |
[
[
"https://www.youtube.com/watch?v=ndlQNicOeso"
],
[]
] |
||
pkw5p
|
AskScience AMA Series- IAMA neuroscientist working on the genetic and cellular basis of eating disorders-related behavior
|
Hello all! I'm a third-year postdoctoral fellow working in a translational neuroscience lab studying the physiological bases of eating disorders. I have also worked on the blood-brain barrier for my thesis work and can speak to the way that compounds get into your brain, some general brain function questions and cross-talk between the peripheral system and the brain. AMA!
Edit: i have barely moved for 4 hours, thanks for the questions everybody!! i'll keep checking back the rest of the weekend so continue to ask if you so desire. please know that i can't speak to your specific eating issues or treatment and if you exhibit behavior that concerns you, please find a reputable mental health professional with which to discuss your issues. good luck and good health.
|
askscience
|
http://www.reddit.com/r/askscience/comments/pkw5p/askscience_ama_series_iama_neuroscientist_working/
|
{
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"Does this include overeating? If so, what are your thoughts on the newer drugs in research trials designed to work on the \"neurological reward circuitry\"?",
"So I'm not a scientist at all, but I'm a recovering anorexic. I really appreciate the work you're doing (even though I'm not sure I would understand it as a layperson). My dad is a recovering addict, and the way the brain is re-wired and changed when a harmful behavior becomes a pleasurable activity is fascinating. Keep us updated with your work, please!",
"Simple question. If this is a disorder that can be traced down to genetics, why does it seem to be almost exclusive to white westerners? ",
"Student aspiring Psychologist here. I have heard of some Psychiatrists prescribing SSRI's in order to combat some of the symptoms of eating disorders such as anxiety in anorexia. From your perspective as a behavioral neuroscientist, does this worry you? Or is this something that actually works? ",
"what do you think of the weight loss product Sensa?",
"I have a close relative who has had anorexia for 14 years and is in treatment for the 5th time. Each time they relapse it gets worse.\n* Do you believe Dialectic Behavioral Therapy can make a difference for people suffering from this insidious disorder?\n* Do you think it is a mental illness?\n* Do you think there will ever be a cure?\n* What do you think of the use of Loxapine for people suffering with anorexia?\n\n",
"Where did you do your Ph.D? ",
"I had a friend who had a \"unclassified eating disorder\". Which according to her was because the symptoms didn't match the known eating disorders. Can you please shed some light on this and explain how eating disorders can differentiate so much so that it is in some cases not possible to give a specific diagnose?",
"So... My obsessive control of what I eat, when I eat it and how it affects my body and workouts is a disease? Holy shit.\n\nEdit; is this related to perfectionism and self esteem issues?\n\nAlso, what does a brain do when it runs out of glucose?\n\nBloodsugar > muscle storage > ??? > fat.",
"Thanks for doing this AMA! Do you have anything to say to someone who would possibly like to get a PhD in Neuroscience? I'm currently getting a BS in Chemical Engineering with an emphasis in Biochemical Engineering. \n\nWhat do you plan on doing after getting your postdoctorate? What COULD you do with this? Other than being a professor of course. \n\nI've always had a hard time understanding what the blood-brain barrier is and how it works. Any chance you could try to Explain Like I'm 5?",
"Curious if your studies have touched on body dysmorphic disorder and its relation to eating disorders and genetics?",
"I've been a bulimic for about 8 years now. I have always wondered if there's a connection between a neurological basis for addictive behavior and eating disorders.\n\nEdit: Also, can you explain the relationship between studying the BBB and eating disorders? And finally, could you elaborate more on your research? Are you working on a molecular level, imaging...?",
"My girlfriend is just a few days short of 1 year 1 month of not making herself throw-up after she eats. We've been dating since she stopped, but started dating a few days after she did stop. She told me about it about a week into dating, which was pretty awesome of her to do so since she had been doing it for a while and hadn't even told her family. I haven't done a ton of research on it myself because I really have no idea what it entails/etc. She has times where she tells me she feels like she would feel much better if she just went and made herself throw up if she is feeling kinda crappy. She hasn't done it and I'm super proud of her for that, but my question is does it ever get to a point where she won't get urges to do it or will it be like that forever? This may be getting out of your field, but can other things form because of this, such as PCOS or something? There was a post earlier this week about PCOS and she doesn't have all the symptoms and stuff, but there are some that she has (ie gradual hair growth on her chin/lip, hairier everything in general). She also has infrequent periods and such. She usually runs daily and eats pretty healthy-lots of vege's/whole grains/all that stuff. She also weighs about 160 lbs and is still very conscientious about her weight. She has 3 sisters and they seem to have a more slender/developed body composition than she does but as far as we know, haven't suffered from anorexia like she did. Like I said, no idea if this is in your line of work, but I thought I'd ask. ",
"Looking at the neural mechanisms of eating, ghrelin is an amino-peptide hormone which stimulates eating when the stomach is empty. If we were to inhibit this hormone systematically and carefully, could a drug be invented to aid weight loss for people who have massive hunger pangs and constant eating?\n\nAlternatively, can CCK be synthesised in a lab and used in drugs to promote satiety after a normal sized meal but for someone who eats a lot of food?\n\nI understand that CCK cannot pass through the blood brain barrier, however there are certain areas of the hypothalamus that are not protected by the barrier?\n\nObviously, if these did work, people would have to force themselves to eat food or they would starve/keep to a diet plan. \n\nWhat do you think ?",
"Is there anything parents can do to help kids if they fear their kids may be genetically susceptible? (my sister who is borderline anorectic is getting a child, one cousin is anorectic, other family members are overweight...). ",
"How much of what we do is nature and how much is nurture? \n\nThis question is something I've been thinking about since reading about that Siberian Fox experiment. The foxes were selected based on their behavior only, but offspring are all behaving in a very similar way. Humans are more complex for sure but we're still based on very similar hardware. ",
"You mentioned a strong hereditary component to AN above. I'm hoping you can talk more about that. How has the hereditary component been measured? (For instance, is it just correlation between family members, or are there any studies analogous to separated twin studies to rule out the fact that family members likely have similar environments/values?)\n\nAre there specific alleles associated with AN, or is the research not at that level yet? If there are specific alleles, what other traits do these alleles seem to affect?\n\nI'm especially curious about the rise of AN-- did AN exist two hundred years ago, unrecognized? Do you think that AN took the form of a different mental illness in the past?\n\nFinally, and excuse the disconnect between this and my previous questions, but what exactly are you working on? You refer to \"we\" a lot-- it sounds as if you're employed by a company researching many different things. Are you part of a team specializing on one particular disorder? Do you run around helping several different teams? How does it work? Which specific disorder(s) are you currently investigating, and how are you investigating them?",
"Serious eating disorders are present in three generations of my family.\n\nSomehow I was spared although I have a sibling and a child who are affected.\n\nThe \"societal pressure to be thin\" doesn't seem to explain the cases in my family, although it is clear that certain personality factors may be connected.\n\nWhat is the state of current knowledge on the genetic basis of eating disorders? Are there any particular genes or epigenetic factors that have been definitely connected with eating disorders?",
"Thanks for providing us this AMA. I'm a binge eater I believe. Just so you know, I don't know if this was relevant but I was misdiagnosed as a kid with hydrocephalus because of my enlarged ventricles. I don't know if there's a connection there at all with my overeating. \n\nAnyways I can pretty much eat as much as I want. I gained about 50 pounds in a month, no joke. I did not feel sick once unless I drank a lot of iced water with the meal. Why do I not feel sick? Or why didn't I..as I have reduced my calories from 10k to 1.5k. I still don't feel full but I've lost around 30 pounds in a couple months. My thyroid has checked out everytime I checked it, btw. ",
"Interesting subject!\n\nSo what do you do experimentally? SNP correlations? Microarrays? Any idea whether its genotype vs. expression? \n\nI don't know much about the BBB. Is there diversity among humans in what can cross it? I.E. do different people have different protein channels or whatnot?",
"What are your thoughts on exercise bulimia/compulsive exercise? Is it officially classed as an eating disorder?\n\nI fall into that category in that I exercise excessively on a daily basis to burn off each day's calories. I get incredibly stressed - to the point of tears - if I can't complete a workout on any given day. I think there may also be an addictive element from the endorphin release. So I'm just interested to know if and how this would fit in with other eating disorders and your general research.",
"I have a disorder where I do not like to try new foods. There is extreme anxiety if I am presented with something that I have never eaten before and this has limited me to a very small number of things that I can eat. It also seems to manifest in what seems like a weird way for me. When my stomach tells me I am hungry, I don't actually feel a desire to eat. I have, in the past, gone for a day or two without eating because I don't feel the need to, though I do feel 'hungry' (its hard to explain how these two feelings are different for me). I guess my question would be what is the physical root of this disconnect between stomach and desire to eat? Is it just a psychological side effect of me not liking many foods, or something more physical/chemical?",
"I don't know if you've ever seen the advertising campaign of Arby's, but basically it's a fast food company that excessively promotes itself as \"good mood food\" on everywhere and decorates its containers with things like \"Crispy outside, juicy inside, happy all over.\" \n\nDo you think it's likely that this weak, but repetitive stimuli could lead to associate learning(or the kind of learning that could ultimately cause people to associate food with happiness, contributing to current problems by targeting those who might be likely to already see food as comforting)?",
" I am a recovering anorexic. I have been this way since I was 13, after the first time I was raped. After that, I developed this very poor body image.I grew up in North Philadelphia,and in my teenage years I took full advantage of the city. I had a bad heroin problem and experimented with many others. My homelife wasn't the best...we were poor and both my parents worked multiple jobs so they were never really around. I was diciplined when I went against their rules...either with my father's leather belt or my mothers biggest wooden spoon. My best friend in elementary schoool lived a few houses down from us, and one day she saw my mother chasing me down the street with the spoon, and told everyone at school. It was traumatizing and we were no longer friends after that. But I was not abused...I wouldn't say. When I was 17 I was in Rehab for heroin and my mother had a very long conversation with me. She apologized for being a little rough and distant throughout my childhood, and told me about her father. She was abused badly growing up by him, and developed a bad eating disorder because of it. I never really believed in the genetic \"predisposition\" for eating disorders or addiction, but after she told me I was never able to stop thinking about it. I am 22 now, and have finally met a man who makes me feel beautiful. I never really had any self esteem until I met my fiance. I am finally able to eat heathy meals without feeling disgusting afterwads. He helps me to get over my past, an, and everyday I make better progress toward living a healthy lifestyle. I am sorry this post was so long. Maybe some of this helps you. Thanks for all your hard work!",
"You're doing some great work--I know more than my fair share of people suffering from AN, so first off thank you =)\n\nBut I have a hard time accepting that there is a genetic cause to AN. Certainly in Western(ized) countries there is enormous social and psychological pressure to be thin, along with the idea of a woman being able to have absolute control over her looks. \n\nHow can you tell the difference between a hard genetic cause and social dynamics within the family (ex: a daughter wanting to be like her very thin mother)? \n\n",
"My brother was anaeorexic for about two/three years. I honestly thought he would die, it was that bad. But something just clicked and he was back to normal, for 1.5 years now its like hes never had it. is he healthy? I'm worried it will come back. What happens next, do most of these patients \"recover\" or is it a matter of time before his feelings of being worthless come back? I never talk to him about it either, ",
"Where does the medical community make the distinction between AN and austere caloric restrictions for weight loss?\n\nThanks for doing this, it's fascinating!",
"What is your opinion of Marijuana and would you consider it helpful for people who are anorexic. ",
"I have nothing to ask, but you rock, and I'd like to buy you a beer. Science rocks. ",
"I'm not sure how to word this question exactly. \nIs it possible for someone exhibiting anorexic syndromes to actually not have an ED but rather Münchhausen('s)? And if it is possible, assuming the behaviour lasts for any significant amount of time, surely s/he would qualify as an eating disordered individual. \nAlso, how might a professional pick out Münchhausen cases from the lot? \n\nI regret that though I know enough about EDs, I am rather ignorant about Münchhausen Disease.",
"I was hoping that maybe you could verify this. I'm 16 years old and whenever i am presented with any new food, i start to panic like i would sooner run out of a room screaming instead of put it near my mouth. I probably sound like a wuss saying that, but i've been drivin to tears before trying to taste a new food (it was bacon), not to mention the whole rapid breathing, sweating deal. I mostly just eat peanut butter sandwiches and chewy bars. I eat in my talanted art teachers classroom during lunch because the smells and sight of most foods, and the.. i guess mannerless way the food is handled and consumed sickens and panicks me. Why is this, though? Why is it so hard for me? I think i heard it is called selective eating disorder. Is that it? How would i go about fixing this? ",
"Are eating disorders contagious? And before you laugh please understand that I know there's isn't a germ or a virus I can catch that will give me an eating disorder. But my girl friend has some eating issues. When she was younger she would binge and hide her eating habits. Her weight has fluctuated severely over the years. She'll gain 20 and drop 30 and vice versa. I on the other hand at 6'2\" never broke 195 lbs and generally wasn't a big eater. I've always hated sweets, loved salty snacks, but generally never was a big eater...always left food on the plate. Since dating her I've gained 20 to 25 lbs and I now eat massive amounts of food. Her and I will binge together, but where she doesn't eat the rest of the day because she has experience with this, I find myself continually eating. Is there any research or documentation on people giving other people eating disorders in the way I'm describing???",
"I'm going to try to make a long story short enough to read, while still providing the necessary details to preface my questions with. \n\nThe year I turned 13 I became addicted to painkillers. A few years later at 15 I started to starve myself and just kicked the pill habit (which wasn't that severe yet,) like it was nothing. I didn't need them anymore. I was diagnosed with AN a few months later and was very sick for a long time. I was hospitalized, my parents were terrified, I lost so much weight I was unrecognizable and I lost most of my friends due to isolation, but NOTHING could make me stop. Nothing was worth losing my \"control\" for, or never feeling that weird sort of high I got from starving ever again. As much as my AN made me feel like shit, it also made me euphoric, and nothing could make me give that up. Until I met my current boyfriend and started using opiates again two years ago, at 17. Slowly since then I have been recovering from AN (while simultaneously spiraling back into drug addiction.) I was able to start eating again. Just a little at first, then in more normal amounts, and recently I have even been able to cut down on some of my disordered habits (such as picking my food apart, eating extremely slowly, chewing forever etc.) I have gained some weight and right now I am just 5 pounds shy of reaching the lowest weight in the healthy weight range for girls my height and age. Psychologically I have been less successful (still totally terrified of gaining weight,) but I don't absolutely hate my body anymore. I am able to recognize that I am quite thin and there are even days that I like my body. \nThe problem is, of course, that I started to recover from AN right as I relapsed into opiate addiction. And this time is ten times worse than it was when I was younger. I do so much more, the withdrawals are so much worse. There has never been a time in the last 6 years of my life that I wasn't either an anorectic or a junkie, and as one problem gets worse the other seems to get better. I have many questions about this and I'm hoping someone can help. \n\n-Is this a common occurrence? It feels like I need one or the other. I want to get clean but I am terrified that I will start starving myself again if I do and honestly, I'd rather be a fucking junkie. Nothing is worth putting my body and mind through the hell that is AN again. Do you think relapse into AN is something I should be concerned about if I try to detox? \n\n-Is it possible/likely that I have another underlying mental illness/disorder that makes me predisposed to both addiction and eating disorders? If that's true, or if it's something genetic, why don't both occur at the same time for me? Could it just be a coincidence? Something I'm subconsciously deciding? This has been tearing me apart for a long time. If I relapse into AN there is a good chance I will die as I came very close last time, and even if I don't it's still a fucking miserable way to live. Opiate addiction is too. I am vaguely aware that I am using my fear of relapse into AN to justify continuing my drug use. Anyway, this has become me just rambling on so I am going to stop, but I would really appreciate if someone could give me their input on this. ",
"Very informative post, thanks for that. I do agree with your hypothesis that OCD and anorexia manifest through similar brain activity, at least this is how it feels. I have had various OCD type behaviors my whole life. Between age 9 and 13 I had an obsession with being afraid I'd puke (I wouldn't eat anything with more than 2g of sugar, take long car rides, would wash my hands til they bled so get rid of flu germs), this mostly went away as I got older, but I was still obsessed with planning, and developed anorexia when I was 18, which was going strong for 2 years but has mostly waned now, although other OCD behaviors are manifesting. I really look forward to more research on this subject, and am thankful that scientists such as yourself are looking into this area.",
"when you're wiping your butt do you ever think; \"damn it! i'm a frigging neuroscientist.\"?",
"I had a brain tumor that was pressing on my hypothalamus for years. I gained weight steadily despite watching what I ate and working out 3-5 days a week. After getting the tumor removed, I have noticed a marked decrease in my appetite, altough I am still eating roughly as much as before. Nevertheless, I have lost 50 pounds and 6 inches off my waist in the past two months while recovering in bed. Do you think it is a reasonable hypothesis that I was suffering from hypothalamic obesity before the tumor was removed?",
"This will probably get buried, but I'll try all the same!\nI was a codeine addict for about a year, in that time food obviously took a second to habit.\nI've been clean for awhile now, something that hasn't either reset itself or is broken, is I never feel hungry any more. I get stomach cramps and a gnawing feeling when I don't eat for an extended period of time but that's it. I feel no urge to eat, and could happily go without food for days. I now force myself to eat every 4-6 hrs, without joy. \nAny idea as to why this could be?\n\nTLDR: ex-opiate addict, don't feel hunger any more.",
"Can you enlighten me on what we know about anorexias besides AN? I won't go into detail about myself, but I'm curious if there's a description for a tendency (possibly linked with depression) to habitually forget meals and/or consciously skip them due to lack of hunger or motivation to eat, rather than body image concerns or OCD behaviors."
]
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1jpcn7
|
why is generation x seen by some people as the generation that dropped the ball.
|
Generation X has done some remarkable things, but somehow they are seen by some as a generation of screw ups. why?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1jpcn7/eli5_why_is_generation_x_seen_by_some_people_as/
|
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"text": [
"Because the baby boomers won't accept responsibility.",
"I think all generations have had to deal with that to some extent, but now it's their turn. \"You kids are so [negative trait here]! Why back in MY DAY...\" The same will happen to us, as it has already.",
"What is Generation X? O.O",
"Generation X were the children of the Baby Boomers. When Generation X grew up, the Baby Boomers, who made up the Woodstock generation, began to fear losing the limelight to a new group of people who were young, setting new trends, and moving popular culture in a different direction. So naturally, the Boomers sought to dismiss the up-and-comers by labeling them with an X, figuratively crossing them out.\n\nAs Generation X began to have children, the Boomers who by now were middle-age, gleefully noticed that their children could also be labeled with a letter, the one following X in the alphabet. And so they were called Generation Y, as in \"Why?\", or \"What's the point?\" It was doubly satisfying to the Boomers because they could also say they held them in so little regard that they couldn't be bothered coming up with any more original name than to use the letter following X.\n\nAs Generation Z approaches, however, trouble lurks over the horizon. If you adopt the same convention of using letters, then after Generation Z you'd either run out, or you'd have to wrap-around and call them Generation A. This is intolerable, because the letter A has positive connotations to it. For example, it represents the highest grade you can get in school.\n\nSo in preparation for this eventuality, they decided to break convention. They impressively refrained from calling Generation Y's children, Generation Z for Zilch/Zero, and called them the Millennial Generation instead. However, whether they resisted temptation, or their voices were merely drowned out -- by now the Boomers were approaching old age and their influence was quickly waning -- is disputable. I tend to think of it as Generation X and Generation Y asserting themselves and not allowing the Boomers to continue their self-absorbed and dismissive ways.\n\nPersonally, I call the Baby Boomers, \"Generation W\". As for what the W stands for, I like to think of it as the W in George W. Bush.\n\n"
]
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[] |
[] |
[
[],
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|
3fpkbk
|
why do countries like switzerland and new zealand have freer economies than the us?
|
In pretty much every list, the US is fairly far away from being at the top. How are these economies different from the US and what about them make them more free?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3fpkbk/eli5_why_do_countries_like_switzerland_and_new/
|
{
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"This presumes that \"free\" is better in some regard. It also presumes a strict definition of the word \"free\". If you mean free in the sense of less government intervention in their economy, its because countries are very very different and have very different needs.\n\nNew Zealand has 4 million people, and a very small and undiverse economy. The US has 320 million people... presumably, they have quite different needs to accommodate their people and economy.\n\ntl;dr: Countries have different needs.",
"ELI5: NZ offers a lot of stuff that the US does not in order to help its people.\n\nELI18: Our Health Care system is set up so that if you have an accident or if there is an emergency, you don't have to pay for it, same with pregnancies. It all goes under ACC and other acts and parts of government.\n\nOur IRD pays for families to have kids (dependent on your gross annual income and how many kids you have). Currently they are paying me $140 a week for being a solo father. Not to mention I am entitled to upto two tax refunds a year (my Working For Families Tax and my Income Tax). All of which has been set up by our government. There is a limit though, after a certain amount of money you earn a year, you will start to receive less and there is a cap. It also takes into account de facto relationships, and marriages.\n\nI could also go out and get an accommodation supplement because of how much I pay for rent and my circumstances etc. That would be $60 a week at most.\n\nIf I need a lawyer and can't afford one (or I am eligible), I can get Legal Aid which is another program which helps with getting a lawyer and not only for criminal cases. However they only cover a certain amount of hours.\n\nAll products in NZ must also show the price with the GST already added so you know exactly what you are spending instead of getting to the counter and finding out that you are a couple dollars short because you forgot to account for the tax.\n\nIncome tax is about 15% and minimum wage is about $14.50/hr. I know there are a fuck ton of other things we do that makes us a freer country than the States, but it escapes me right now."
]
}
|
[] |
[] |
[
[],
[]
] |
|
2wto4p
|
why are fruit snacks flavoring/coloring distributed unequally?
|
Every fruit snack pack that I open has a random set of fruit snack flavors in different quantities which makes no sense to me. Wouldn't they want to supply their consumers with an equal amount of each color?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2wto4p/eli5_why_are_fruit_snacks_flavoringcoloring/
|
{
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"cou0aos"
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"text": [
"The assembly line has to stop for half a second every time they start to pour something into the package to prevent spillage. Pouring in two reds and two blues etc. could take about three to five seconds, whereas just pouring them in from one container would take maybe one second. Also, it makes it easier to ensure that every package gets the same weight if they don't also have to worry about color ratios."
]
}
|
[] |
[] |
[
[]
] |
|
gm91i
|
Orthostatic hypotension and vision--or, why can't I see when I stand up?
|
I have very low blood pressure and I get blackouts all the time when I stand up. As an entering neuroscience grad student (MD/PhD), I can't help but wonder about it while I'm standing still, waiting to see again: why exactly does this affect my vision more than any other function of my brain? I tried googling it and all I can find are medical sites that list loss of vision as a symptom of orthostatic hypotension, but nobody says *why* that happens. What part of the visual system (retina, optic tract, visual cortex) is being affected, and how does this result in tunnel vision and sparkles of light?
|
askscience
|
http://www.reddit.com/r/askscience/comments/gm91i/orthostatic_hypotension_and_visionor_why_cant_i/
|
{
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"text": [
"The same thing happens to me.\n\nFrom what I have gathered, it's because in these situations there's only so much oxygen to go around up there. Because your brain is far more important than your eyes, blood/oxygen is diverted away from them in order to supply the brain, lest it become damaged.\n\nThere could be more to it than that, though.\n\nWhen this happens, don't just stand straight up and wait! Put your head down so that the blood can more easily flow. You might look stupid but it's better than blacking out!",
"Retinal hypoperfusion. Not only is your brain not getting enough oxygen / bloodflow but neither is your retina. \n\nI wish I could give you a nice link to look at but I pulled it out of one of my medical texts."
]
}
|
[] |
[] |
[
[],
[]
] |
|
sd2lg
|
Which can stop faster: a motorcycle or a car?
|
There is constant bickering both ways, please provide some references with apples to apples data. I can find a few listings of various stopping distances but they are clearly measured inconsistently, sometimes including 'perception time' or some other fluff. Source with specific stock models will be useful- and don't use a McLaren F1 for obvious reasons. I will post to /r/motorycles afterward so as to shut the book on the arguments there.
|
askscience
|
http://www.reddit.com/r/askscience/comments/sd2lg/which_can_stop_faster_a_motorcycle_or_a_car/
|
{
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"c4d2kyw"
],
"score": [
2
],
"text": [
"A car has, relatively, a much lower center of gravity compared to its wheelbase, so will be able to apply proportionally more braking force without flipping over."
]
}
|
[] |
[] |
[
[]
] |
|
28753u
|
Did they British Military stopped with "local" regiments after WW1?
|
I was in Ieper yesterday at the Menenpoort and I though by myself. I see a lot of "local" regiments then I tough of something I read in the newspapers arround D-Days that the American Military stopped with "local/friendship" regiments after D-Day because the youth of certain communities where decimated. Now is my questions is did the British stop with these regiments after WW1, because they already saw that the youth was decimated?
Edit: Sorry for the error in the title.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/28753u/did_they_british_military_stopped_with_local/
|
{
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],
"text": [
"I'm assuming you are referring to what were called \"Pals battalions\"; units that were collected from the same local recruitment posts to allow volunteers to be with people they knew already at the front. _URL_0_\n\nI'm afraid I can't find another source at the moment, but after conscription began early on in 1916 new Pals battalions were no longer formed and those that remained were later absorbed into larger formations.\n\n*However*, that is not to say that British military units do not still have a regional focus in some cases and celebrate regional heritage and recruit from certain areas. One offhand example I could give you is the [Yorkshire Regiment.](_URL_1_)"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Pals_battalion",
"http://www.army.mod.uk/infantry/regiments/23987.aspx"
]
] |
|
1s0lwn
|
What role does Insulin have in memory?
|
this is in conjunction with an article im reading about the link between type 2 diabetes and alzheimers, it says there is a link but doesnt go any further as to say why.
|
askscience
|
http://www.reddit.com/r/askscience/comments/1s0lwn/what_role_does_insulin_have_in_memory/
|
{
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"cdtik35",
"cdvhf4t",
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],
"score": [
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3,
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"text": [
"My first thought when I read this question about type 2 diabetes and alzheimers actually wasn't insulin but glucocorticoids (GC), which are hormones involved in glucose metabolism, but they also have many psychological effects. Exposure to high levels of GCs for example can lead to cognitive impairments especially in older adults (see [here](_URL_0_) ).\n\nI don't know much about type 2 diabetes, but I suspect that there would be endogenous changes in GC levels. I did find an [article](_URL_1_) that links glucocorticoid *treatments* for diabetes with cognitive impairment. ",
"I can think of a few reasons that type 2 diabetes and Alzheimers may be linked, and none have to do with insulin directly...\n\n1. Diabetes can cause damage to your blood vessels. Types of dementia may occur due to brain damage that is often caused by reduced or blocked blood flow to your brain. Many people with diabetes have brain changes that are hallmarks of both Alzheimer's disease and vascular dementia. Some researchers think that each condition fuels the damage caused by the other.\n\n2. People with type 2 diabetes also have chronically high blood sugar, and while neurons are some of the more demanding cells as far as glucose goes, too much glucose with kill them. That's why diabetics get diabetic nephropathy in which peripheral neurons die and they get numb, tingly, painful extremities. If this happens to central neurons, it's very bad, and could definitely lead to cognitive deficits.\n\n3. Also, as u/glarn48 pointed out, Glucocorticocoids, like cortisol, are high in type 2 diabetes. The glucocorticoid hypothesis of brain aging and Alzheimer’s disease proposed that chronic exposure to GCs promotes hippocampal aging and Alzheimers. ",
"A little bit of a late response but I think this is an interesting question. Before talking about the link to Alzheimer's be aware insulin is actually an important signaling molecule/growth factor in the brain. In fact, the brain produces its own insulin (rodents even have a brain specific isoform) as well as being able to respond to peripheral insulin. In addition, neurons in culture will die without insulin. Insulin's exact function is still being worked out but it seems to play an important role in the ability of neurons to have a proper shape and form connections with each-other. \n\nThere have been several papers on possible effects of amyloid-beta on insulin receptors - [for example](_URL_0_). The upshot seems to be that amyloid-beta oligomers (thought to be an important pathogenic agent in alzheimer's) negatively impact the function of insulin in the brain. In type II diabetes many tissues in the body are already insulin resistant which, combined with a potential effect of amyloid-beta, may have an especially detrimental impact on the ability of these neurons to respond to insulin resulting in cell death... dendritic spine loss... etc\n\nAnyways, this last part is just a guess - exactly how a potential effect of amyloid-beta on insulin receptors may relate to type II diabetes is up in the air as far as I can tell. Maybe some aspect of hyperglycemia ramps up amyloid production, or the detrimental effects of diabetes on the brain impair the ability to clear amyloid, or maybe it is part of an initiating event unrelated to amyloid beta... there are a lot of possible explanations but hopefully this answer at least provides some sort of a link between the DMII and alzheimer's."
]
}
|
[] |
[] |
[
[
"http://www.jneurosci.org/content/26/35/9047.short",
"http://www.eje-online.org/content/166/5/861"
],
[],
[
"http://www.fasebj.org/content/22/1/246.long"
]
] |
|
2zrw4y
|
if cooked, would human meat be red, white, or an "other" similar to pork.
|
I thought about it, and it could be red like beef, since cows and humans are both mammals. However, pigs are mammals too, so it could be that "other white meat" category or whatever that is. I don't think it'd be white meat since that's found in poultry and humans aren't birds. I've always wondered this and I didn't really want to see for myself so.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2zrw4y/eli5_if_cooked_would_human_meat_be_red_white_or/
|
{
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"cplrupe",
"cpls6da",
"cpls7o2"
],
"score": [
2,
6,
5
],
"text": [
"The human psoas major muscle is filet mignon in cows.",
"Cannibal serial killers like Arthur Shawcross and Jeffrey Dahmer claim that humans taste like roast pork. That freaks me out because I love roast pork.",
"It turns white when cooked by steam. Source ... me.\n\nI severely burnt my hand with steam some years ago which flash cooked some of my flesh. I can provide the whole story but it is a bit long.\n\n"
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
70dess
|
do all subatomic particles already exist? and/or how are they created?
|
I've been googling around but information seems scant here. Did all subatomic particles that exist get created with the advent of the universe or do they still pop into being now and then?
Watching a documentary on sub-atomic particles and how they behave got me to wondering this. So if they are what matter is made up of it's logical to assume they were created with all matter during the universe coming into existance. But it also got me wondering if certain situations have to be present to still 'birth' them. I've read a few articles that suggest subatomic particles can be 'created' during certain experiments but are they actually created or are we just rendering them visible to our instruments?
I feel like an idiot asking this but it's explain like I'm five so it's safe to assume that's kinda the case.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/70dess/eli5_do_all_subatomic_particles_already_exist/
|
{
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"dn2j5v5",
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"text": [
"As far as I know no. Matter is just one form of energy and transference between matter and other forms of energy are possible. \n\nDuring subatomic processes particles particles with a mass break up into massless photons (aka light) all the time. The reverse can happen too.\n\nI don't know whether this has been proven possible for all known particles but the fact that it happens at all means we can safely dismiss the idea that all kinds of matter are build from tiny lego bricks that are just assembled in different ways.\n\nThe only real constant we seem to have found so far is energy. If you observe an object you can be quite sure that the energy making up that object has existed as long as the universe but it might not have always been in the form of matter.",
"I'm just going to base my answer on the Standard Model. It's the theory in particle physics that explains three of the four fundamental forces (electromagnetic, weak, and strong interactions; it doesn't explain gravity), and also classifies all known elementary particles.\n\nSince it's theory, we need validation - this comes from testable predictions given by the theory, and experiments confirm these; amongst these would be well the presence of all the particles expected by the theory. By the use of particle accelerators, we've managed to find evidence of the existence of all but one particle (the missing particle being the graviton, the hypothetical particle that 'mediates' - i.e. carries out - the force of gravity).\n\nAll particles that exist today are due to a small asymmetry when there were particles and antiparticles being created in the big bang - the imbalance was 1 in ~10 billion (by some estimates) and when the ~10 billion pairs of matter and anitmatter vanished, the resulting fraction left over, even though tremendously small, formed all the visible matter (particles, whatever) in our universe.\n\nThat answers part of your question - all the particles exist (save the graviton whose existence we haven't confirmed), just in different bound states - e.g. protons are subatomic particles but are themselves comprised of smaller particles such as quarks and gluons), and all the particles/matter we have today is a result of an small symmetry being violated at the time of the Big Bang.\n\nThe second part - can they be created? Due to conservation of energy you cannot just create matter that lasts. This is an important distinction I'll get to in a second.\n\nOne way to create new particles is to smash together existing ones at massively high energies in particle accelerators, and hope that the spray of particles that comes out of the detector contains a few of the ones we want to observe/see.\n\nAs for popping into being, this does occur but not the way you'd expect it to. In quantum mechanics, there's a thing known as the uncertainty principle - essentially it states that we cannot know the EXACT position and EXACT momentum of a particle - there is a limit to how accurately the two can be known. Furthermore, knowing one of them exactly means the uncertainty in the other is infinite. The principle also applies to energy and time (although this explanation I'm giving is hand-wavy since I'm trying to simplify it) - a consequence of this is the following. Say you had a system that's a vacuum, and you measured it for a short period of time (incredibly short period). The uncertainty in the time would be very very small, but due to the uncertainty relation, the uncertainty in energy would therefore have to be large - therefore for very short periods of time, pairs of virtual particles and virtual antiparticles could spontaneously form and then annihilate, causing vacuum fluctuations.\n(virtual essentially means that what we observe has the properties of ordinary particles and antiparticles, but the existence time of these are very short due to the uncertainty principle).\n\nI understand that this goes a bit beyond ELI5 but I hope it helps.\n\nIf anyone finds mistakes in this please let me know and I will correct them accordingly, I'm only an undergrad student and not very good at physics so I might have fudged up a bit.",
"We don't know for sure. \n\nWe know that some subatomic particles definitely do exist because we have measured them through natural processes. However, many of them we can only detect the way a toddler might figure out what's in a toy: by smashing something bigger into little pieces. \n\nImagine you wanted to know what cars are made out of. We can take one apart and see what all the various pieces are. We know when we've found all the parts by removing parts until we see there are no parts left to remove. \n\nThe way we take atoms apart is by smashing them. Depending on how hard you smash them different pieces \"fall off\" and we detect these as different sub-atomic particles. \n\nHowever, there is a twist: we can't look at the result of a collision and judge if there are more parts left that can be removed the way we might with a car because sub-atomic particles don't behave like car parts. We have models that predict what we think we should find, just like you would predict to find an engine and tires on a car but it is possible that our model is incomplete in some way. \n\nBecause there is a limit to how fast we can accelerate a particle (the speed of light) we can only smash things so much before nature says no. \n\nAnd so, the best we can do is say whether or not all the parts we were looking for have been found yet. \n\nWe have not show experimentally what sub-atomic particles cause gravity or dark matter/energy. The Standard Model is incomplete. So, like I said: we don't know. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
o0o0k
|
Does a pickup truck get better gas milage with the tail gate up or down?
|
askscience
|
http://www.reddit.com/r/askscience/comments/o0o0k/does_a_pickup_truck_get_better_gas_milage_with/
|
{
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"text": [
"They tested this on MythBusters. Two identical trucks driven the same identical distance at the same speed. One had the gate up and the other had the gate down. They also tested it in a water tunnel (like a wind tunnel but for water) and found that the gate up left a cushion of air in the truck bed that the passing air passed over. With the gate down, the passing air dropped into the bed and dragged along it.\n\nThey found that a truck gets better mileage with the gate up!",
"It's minimally better gas mileage if the tailgate is up. [Check it.](_URL_0_)\n\n "
]
}
|
[] |
[] |
[
[],
[
"http://papers.sae.org/2004-01-1146"
]
] |
||
8733nc
|
meaning of no country for old men
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8733nc/eli5_meaning_of_no_country_for_old_men/
|
{
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"text": [
"I personally saw that it was referencing how Tommy Lee Jones' character felt as if crime and increasingly immoral behavior was taking over the society he grew up in, and that the morality of his generation wasn't able to hold a candle to what is to come.\n\nSorry if that's hard to read. ",
"Both the film and the book take their titles from W.B Yeats poem 'Sailing to Byzantium' where the opening line is \"That is no country for old men\" if that's what you're asking. On a very, very basic level the poem is about growing old. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
8x4fgl
|
why it's still so warm at 2am after a hot day. where's the heat still coming from and why hasn't it just risen into the air?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/8x4fgl/eli5_why_its_still_so_warm_at_2am_after_a_hot_day/
|
{
"a_id": [
"e20q7g1"
],
"score": [
2
],
"text": [
"The sun warms the surface of the earth, which reradiates heat into the air mass above it. It takes time for both to cool down, even after the sun goes down."
]
}
|
[] |
[] |
[
[]
] |
||
1uki4j
|
with all this -30º weather and such, how long can an average human or animal withstand these temperatures?
|
If we were to start "freezing alive" what body parts or organs would give out first?
I'm asking because I just watched a mailman walk for about 15 minutes, door to door, like it's no big deal.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1uki4j/with_all_this_30º_weather_and_such_how_long_can/
|
{
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"cej12xj"
],
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"text": [
"Freezing to death does not mean you die from solidified flesh. \n\nYour normal body temperature is about 37ºC. The freezing point of water is 0ºC. There's a lot of room in between the optimal operating temperature of the body and the point at which the flesh would actually start to freeze solid. \n\nThe most likely thing to kill a person or animal who is exposed to the cold for too long is hypothermia. If you lose too much body heat to the outside environment and your core body temperature drops too much, your body systems become unable to function normally. There are medical definitions for the stages of hypothermia and what happens to the body at those temperatures.\n\nMild, 32-35ºC: shivering happens, and weird things can happen to your blood pressure and blood sugar as your body attempts to keep warm.\n\nModerate, 28-32ºC: you shiver harder or intermittently, you start to lose muscle control and get clumsy, and you might feel confused or react sluggishly to things happening. Your extremities (face, hands and feet) will lose blood flow and become numb and pale/blue-looking.\n\nSevere, below 28ºC: you get really confused and have trouble staying conscious or remembering things, and your heart and respiration start to fail. \n\nAll of this happens long before your internal body temperature gets anywhere near the freezing point of water, so you don't die from freezing solid like an ice cube. You'd be dead long before you got that cold.\n\nThe record for the coldest body temperature that a person has survived is held by a little girl from Sweden who fell into the ocean in the middle of winter a few years ago. When she was found her body temperature was only 13ºC, but she was still alive, and was able to be rewarmed. (I'm having trouble finding any information on whether she is \"back to normal\" or if she survived with permanent injuries or disabilities.)\n\nThe bottom line is that if you're dressed warmly, are healthy and fit, and are active when you're outside, you aren't going to freeze to death walking down the street like the mailman. The mailman could risk hypothermia if he's dressed too warmly, because if he sweats in his warm clothes he'll lose body heat faster. He should also be careful of frostbite, which is where extremities like ears and nose can actually freeze even though the internal body temperature is not hypothermic. \n\n"
]
}
|
[] |
[] |
[
[]
] |
|
1fv5iy
|
Why have certain ethnic terms taken on pejorative connotations over time when their initial use seems not to have had any?
|
I asked the mods if it was okay to post this question, and they agreed that it was. This post will contain language that some may find offensive, but it is not my intention to offend. I'm just asking a question about it.
Now I know that there has historically been a lot of problems with people using careless or purposefully demeaning terms to describe people of other races. They haven't all died out, either. An uncle of mine was once called a "dago" to his face, and that was in the 1990s.
But there are some that now seem to be offensive but which don't seem to have any of that history of being used to deliberately cause offense. Two major examples of this would be "Esquimaux" and "Hindoo". I have seen people take offense to these terms on several occasions in my life ("Hindoo" was called so "obviously racist" by a friend of mine that she refused to even explain why), but they seem to have originally been good faith efforts to transcribe the words into English. Why have they fallen out of favor? And why are our own spellings of those words any better or less offensive?
I'd ask the same of three words I've seen used when discussing Islam, though one of them has a slightly different "thing" going on.
It seems to have been a regular thing to call what we now refer to as Muslims "Mohammedans" or "Musulmen." "Mohammedans" is obviously sort of different, in that it isn't about trying to spell the word properly but instead about describing this religion in the same way as Christianity is, but "Musulmen" seems never to have been intended to offend and is apparently still used unproblematically in other languages. I ask the same question about "Mahound," for "Mohammed." It looks really weird to us, but anyone who has heard "Mohammed" pronounced properly in Arabic can see exactly why this spelling might have taken off.
Two questions, to make it all more clear:
1. Why have these spellings or renderings come to be taken now as insulting or bigoted?
2. What makes the revised spellings or renderings better?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1fv5iy/why_have_certain_ethnic_terms_taken_on_pejorative/
|
{
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"text": [
"Is there any evidence that the term \"Indian\" as a description for the people who inhabited North America before European colonization was meant to be a pejorative? My understanding is that it was just a mistake that came into common usage. \n\nThe modern term, \"Native American\" that some have adopted to replace the therm \"Indian\" is a misnomer IMO, as the word \"native\" describes one's place of birth, not their ancestry.\n",
"I cannot speak for all of these words, only for the instances my language history professor covered in her lectures.\n\n1.\n\nAs far as I recall, the term \"Esquimaux\" means \"those who devour raw meat\" and actually only referred to a certain group within the Inuit population who were called this since they indeed ate raw meat (what even makes sense if you think of a freezing temperature and that the warmth of a freshly hunted animal may as well save your life) and, let's face it, people like to boil things down to what they think is remarkable. Since every Inuit looks the same to the average European, however, the term \"Esquimaux\" came into common usage and people forgot what it actually meant; the Inuit, who knew the meaning of the word, then took offense to being reduced to and stereotyped as people who eat raw meat. \n\n\"Hindoo\" is derogatory since it was used for anyone from the Indian continent, regardless where they came from exactly or whether they really were Hindus. It's like referring to every state in the old Soviet Union as Russia, Poles and Ucranians will blow their top if called Russian; it robs them of individuality and reduces them to subordinates of what happens to be the biggest country with a similar language and similar looking people around.\n\n\"Musulman\" is a European version of the Persian word \"musliman\" which means Muslim. With the rising domination and cultural belittling of what the \"Occident\" saw as the \"Orient\", a term which is purely a construct of cultural practice in order to make yourself look superior, for \"Orient\" could be anything from Turkey onwards (even parts of Africa were considered to be part of the \"Orient\"), \"Musulman\" simply meant \"resident of the Orient who is a Muslim\", which, with the aforementioned connotation of \"Orient\", starts to imply pejorativity. During the Nazi Era in Germany, people in concentration camps who were so extremely emaciated they had lost all will to live and simply reverted to a half-awake vegetative state were referred to as \"Musulmen\", so that term added additional horror.\n\n\"Mohammedans\" only covers a certain branch of Muslim belief, like e.g. Catholicism in Christianity. Basically, the believe the same thing, and then again, there are differences, the one here being whether Mohammed is a holy person or not. A Catholic wouldn't like being called a Protestant either.\n\n I've never heard \"Mahound\" before.\n\n\n2.\nA revision in spelling usually means you thought about a word long enough to realize something's wrong with it, and that effort adds value. I would dare say, however, that in case of lot of words not even a revision in spelling can erase something that has become ingrained in people's minds as associated with that word for centuries.\n\n",
"The people who were writing about \"Esquimaux\" and \"Hindoo\" and \"Mohammedans\" were not exactly doing so up to the standards most people expect today (i.e., not ridiculously racist). Take a look at [this book](_URL_1_) for example.\n\nThese words are seen today as insulting and bigoted because they were, in a lot of cases, being used in writings that *were* insulting and bigoted. The revised spellings don't have that sort of baggage- yet. (They may still in the future, thanks to the [euphemism treadmill](_URL_0_) ). \n"
]
}
|
[] |
[] |
[
[],
[],
[
"https://en.wikipedia.org/wiki/Euphemism#Evolution",
"http://books.google.com/books?id=85wBAAAAQAAJ&pg=PA111&dq=%22Mohammedans+are%22&hl=en&sa=X&ei=YzmyUYqVOIezyAG35ICICQ&ved=0CEUQ6AEwBA#v=onepage&q=%22Mohammedans%20are%22&f=false"
]
] |
|
2qz5m3
|
Because we have our noses to smell, ears to hear, etc., is it possible that there is other major senses that humans don't know about because we lack the proper anatomy or tools?
|
Most objects in the physical world have a different feel, smell, sound, taste, and look differently (things our 5 senses can detect). Is it possible that objects all have a different characteristic that we have no idea about.
|
askscience
|
http://www.reddit.com/r/askscience/comments/2qz5m3/because_we_have_our_noses_to_smell_ears_to_hear/
|
{
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"text": [
"It would be more accurate to say say that objects have different characteristics that we can't sense but *do* know about. The [19](_URL_1_) senses that humans have don't include the [multiple examples on Wikipedia](_URL_0_) of non-human senses or yet more exotic senses that may be imagined, such as, say, \"sense of presence of iron\".",
"I don't think objects have characteristics that we have no idea about because we can detect them with equipment. There are a few more senses we could have sure. Magnetic field sense, radiation sense, you could see how hot something is if you could see in the IR spectrum of light, a sonar sense to tell exactly how far away something is.\n\nEdit: Also if you really think about it smell and taste are both sensing chemical composition so they are kinda the same characteristic detection. "
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Sense#Not_analogous_to_human_senses",
"http://en.wikipedia.org/wiki/Sense#Non-traditional_senses"
],
[]
] |
|
5fkrgz
|
how does your brain decide you like/dislike a certain song? what influences that? and why do we all like different songs?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5fkrgz/eli5_how_does_your_brain_decide_you_likedislike_a/
|
{
"a_id": [
"dalif4p"
],
"score": [
5
],
"text": [
"Basically, it comes down to sensing versus perceiving. Generally everyone senses the same things the same way, from vision to taste, excluding those with sensory deprivations (colorblindness, deafness, etc.). \n\nPerceiving is a different story. It's all in your head. We attach meaning to different sensations. Like when you see your SO and get happy if you're in a great relationship. Basically you attach meaning to different sounds you hear. People tend to like major keys that are consonant, but of course not all because different people attach different meanings based on their experiences!\n\nHope this helps, this is the first ELI5 explanation that I've done! Feel free to ask further questions!"
]
}
|
[] |
[] |
[
[]
] |
||
7ph70c
|
what is putin's and russia's ultimate goal in undermining foreign democracies?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7ph70c/eli5_what_is_putins_and_russias_ultimate_goal_in/
|
{
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"text": [
"Russia competes with other countries for economic power and for military dominance of nearby areas. For the past 20 years or so they've been doing rather poorly. Weakening other countries' governments gives them a better chance.",
"The same as other countries who interfere with the politics of another country (the US has done this for decades) - to have a more favorable government to him. Put people in power who are pro-Russia. People who will remove economic sanctions, make profitable trade agreements, etc.\n\nThe US used to basically own Iran's government until 1979 when the revolution there deposed the Shah. The only difference is that they weren't a democracy, but the results are the same.",
"It is basic geo-politics. \n\nMost powerful regimes don't really care about the nature of other regimes. For example, the United States supports an Islamic monarchy in Saudi Arabia, a strange semi-theocratic/ethno-centric liberal democracy in Israel, and a highly confessionalist republic in Lebanon. The US supports these regimes because they are friendly to the US (generally) and are important economic and political partners in the region. The countries toward which the US has been very hostile are also \"all over the place\" politically (Iraq was a dictatorship, Nicaragua was a semi-socialist democracy, etc). \n\nRussia supports whoever supports its regional interests. Putin probably doesn't care how Americans choose to live their political lives, but the US is really at Russia's doorstep. The US has allies near Russia that impede Russia's plans. Turkey, for instance, is a barrier to warm water ports, so they are America's friend even though American kind of hates that regime. \n\nSo Putin wants to destabilize Western democracies because Western democracies impede his plans for the region. It's very boring actually, when you think about it."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
2rw8ks
|
if i have a 1360x768 monitor, is there any point in watching videos in higher quality than 720p?
|
1080p videos often do *seem* clearer, but that could easily be placebo :P
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2rw8ks/eli5_if_i_have_a_1360x768_monitor_is_there_any/
|
{
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],
"text": [
"You won't be seeing 1080p on your monitor, but the 1080p video may be better depending on the compression the video has been through. It's possible that taking the compressed 1080p video and letting your computer scale it down to 720p gets you a better result than the compressed 720p file, because the 1080p file was probably allowed to be bigger.",
"With YouTube (and many other video streaming websites) the quality might say 1080p, 720p etc but these settings are actually related to bitrate. The bitrate is the number of \"bits\" transfered per second and in this case, video bits. The higher the \"resolution\", the greater the bitrate and as such higher number of video bits. The effect will still be greater if your monitor was a higher resolution, but a choosing a higher resolution video quality will improve your video clarity despite your actual monitor resolution."
]
}
|
[] |
[] |
[
[],
[]
] |
|
2hkgua
|
why is it that even though u2's free album on apple is doing so bad, apple is still advertising it.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2hkgua/eli5why_is_it_that_even_though_u2s_free_album_on/
|
{
"a_id": [
"ckthnf3"
],
"score": [
2
],
"text": [
"Statistics: Even if 30 % obnoxious loud redditors are kicking and screaming still leaves you with 70 % mildly happy U2-fans/don't give a shitters."
]
}
|
[] |
[] |
[
[]
] |
||
2i3i7q
|
How Did We Map The Milky Way Galaxy?
|
At a much smaller scale, we achieved mapping the Earth by physically traveling, inhabiting, and viewing from space, all parts of the globe. However, the enormity of the galaxy limits us to nearby satellites and telescopes. We cannot just send a satellite beyond the galaxy to view upon its entirety as we did with Earth (and even our solar system).
I'm left to assume that we pieced all the images and all the data together to get what we feel represents the Milky Way. I am interested in this process, if Reddit could so kindly explain!
|
askscience
|
http://www.reddit.com/r/askscience/comments/2i3i7q/how_did_we_map_the_milky_way_galaxy/
|
{
"a_id": [
"ckz21co"
],
"score": [
2
],
"text": [
"The Hardest Problem in astronomy is figuring out the distance to things. We've been recording what the sky looks like in 2 dimensions for centuries, but if you want to make a map of our galaxy, you essentially just need to take all the objects your telescope sees and assign them distances. A whole lot of astronomy would be made way easier if we knew the distance to everything (which is why everyone is so excited about [Gaia](_URL_1_) which is trying to do exactly that).\n\nTo get the distances to things, astronomers use a bunch of different methods that a generically called the [distance ladder](_URL_0_). Parallax is the best way, which is what Gaia is doing, because you just use simple trigonometry as the Earth moves on its orbit. If you can't measure a parallax, then you have to resort to approximations where you assume you know how bright something should be intrinsically, and compare that to how bright you see it. This gets pretty messy very quickly, and so our error bars can be large.\n\nThat's pretty much the gist of it though, just observe everything and then try to use all the tools available to you to estimate a distance. Then you plot all the things and you end up with a rough map of the galaxy. The other problem is trying to see what's on the other side of the galaxy when there's so many stars and gas and dust in our way. This is why astronomers use infrared, microwaves, and radio telescopes, since those wavelengths all are better at piercing through dense environments to get to us. It's still tough though, and we're least certain about what things are like directly on the opposite side of the galaxy."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Cosmic_distance_ladder",
"http://sci.esa.int/gaia/"
]
] |
|
8ry8zu
|
Since 1944, Arabs have been deemed white by law in the US. Why?
|
I've seen this ~~apparent~~ fact mentioned in a few threads recently so I decided to google it. For the most part the articles I've found all seem to quote or derive from this opinion piece from [Al Jazeera](_URL_0_).
When where and why did this happen?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/8ry8zu/since_1944_arabs_have_been_deemed_white_by_law_in/
|
{
"a_id": [
"e0vblm9"
],
"score": [
97
],
"text": [
"This question is complex, and that's magnified by the complexity of Arab identity. \n\nIn 1909, one Syrian was allowed to become a naturalized citizen because the judge in his case declared \"I consider the Syrian as belonging to \\[the white race\\]... He is not particularly dark, and has none of the characteristics or appearances of the Mongolian race.\" In 1914, another immigrant from Syria was denied naturalization because the judge in that case declared \"Syrians might be free white persons, \\[but\\] not that particular free white person to whom the act of congress had donated the privilege of citizenship\" - basically, that Syrians were the wrong kind of white. (This particular judgment was reversed on appeal - after all, if you start letting everyone make their own calls on who's white then all kinds of mischief could result.) \n\nThat case, *Dow v United States (1915)*, established that Syrians were officially white. However, this did not include Arabs from North Africa, or from the Arabian Peninsula, and the situation remained confused. Individual judges issued conflicting rulings. \n\nThe issue of Arab whiteness was resolved in 1943 when the Immigration and Naturalization Service declared finally that all Arabs were to be considered white - the first court test of this came in 1944, in the case [Ex parte Mohriez](_URL_0_). I'll include a bit of it, with citations omitted (you can click that link to read the full opinion). It's important to note that this ruling was issued just a few months after the repeal of the Chinese Exclusion Act:\n\n > In the understanding of the common man the Arab people belong to that division of the white race speaking the Semitic languages. Both the learned and the unlearned would compare the Arabs with the Jews towards whose naturalization every American Congress since the first has been avowedly sympathetic... The Arab people stand as one of the chief channels by which the traditions of white Europe, especially the ancient Greek traditions, have been carried into the present. It follows that even by the narrow criteria which were adopted in the opinions of Mr. Justice Sutherland the Arab passes muster as a white person. \n > \n > ...A person ought not to be encouraged to come here to live and to have children born here, who under the Fourteenth Amendment will automatically become citizens, unless we are prepared to give him the advantages of, and expect him to assume the obligations of, United States citizenship. It is contrary to our American creed to create a superior and inferior brand of permanent residents. \n > \n > And finally it may not be out of place to say that, as is shown by our recent changes in the laws respecting persons of Chinese nationality and of the yellow race, we as a country have learned that policies of rigid exclusion are not only false to our professions of democratic liberalism but repugnant to our vital interests as a world power. In so far as the Nationality Act of 1940 is still open to interpretation, it is highly desirable that it should be interpreted so as to promote friendlier relations between the United States and other nations and so as to fulfill the promise that we shall treat all men as created equal.\n\nFor more, see *Race and Arab Americans Before and After 9/11: From Invisible Citizens to Visible Subjects* (Amaney Jamal and Nadine Naber, editors)."
]
}
|
[] |
[
"https://www.aljazeera.com/indepth/opinion/2015/07/arabs-white-150716110921150.html"
] |
[
[
"https://law.justia.com/cases/federal/district-courts/FSupp/54/941/1739378/"
]
] |
|
mch34
|
waterboarding, please.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/mch34/eli5_waterboarding_please/
|
{
"a_id": [
"c2ztq78",
"c2ztwma",
"c2ztq78",
"c2ztwma"
],
"score": [
8,
2,
8,
2
],
"text": [
"Waterboarding is a technique that creates the sensation of drowning even though you actually aren't, by exploiting the prisoners gag reflex which is meant to stop choking.\n\nIt is used in combination with questioning to forcefully extract information from an individual (who would not have given it up otherwise) by inflicting pain and suffering until they break, that is, will give the interrogator what they want in order to stop the waterboarding.\n\nIn it's most mild form, waterboarding is a very unpleasant sensation. Leading into extreme forms of the interrogation technique: waterboarding can be extremely painful, cause damage to organs, damage to limbs (where a prisoner struggles against his or her restraints in an attempt to stop the act or free his or her self), cause oxygen deprivation and can even result in death of the individual through dry drowning (where the lungs are unable to extract oxygen) or severe physiological distress.\n\nWaterboarding can also cause severe psychological distress, often lasting years after the event.\n\nWaterboarding is used as it is relatively easy to carry out, realistically only requiring a way to restrain a prisoner so that water accumulates on their face, cloth and a source of water to pour over that cloth. Waterboarding can also be drawn out over a long period of time which allows the interrogator control of the duration and the intensity in which it is carried out.\n\nThere has even been claims that a prisoner has been waterboarded so much that their electrolyte levels dropped to a dangerously low level resulting in the death of that prisoner, because of the amount of water used diluted this balance. This suggests that the technique can be used in a controlled fashion for days on end.\n\nElectrolytes allow our muscles and nerves to function correctly and without them causes serious problems. Electrolyte imbalances can become medical emergencies if left untreated.\n\nEven though a mock execution is highly psychologically damaging (using an unloaded firearm or one that is loaded with blanks) by climaxing extremely quickly and severely, it can't realistically be controlled in the same way that waterboarding can be.\n\nI would assert (from what I have read of the subject) that you could only pretend to execute a prisoner a finite number of times before the prisoner loses the will to live (since they have more or less hit rock bottom), whereas the amount and duration of pain (even though at a much lower level) that can be caused with waterboarding allows the prisoner to consider that his or her situation could get much worse.",
"It's a torture technique that simulates drowning and in meant to invoke a panic response. \n\n",
"Waterboarding is a technique that creates the sensation of drowning even though you actually aren't, by exploiting the prisoners gag reflex which is meant to stop choking.\n\nIt is used in combination with questioning to forcefully extract information from an individual (who would not have given it up otherwise) by inflicting pain and suffering until they break, that is, will give the interrogator what they want in order to stop the waterboarding.\n\nIn it's most mild form, waterboarding is a very unpleasant sensation. Leading into extreme forms of the interrogation technique: waterboarding can be extremely painful, cause damage to organs, damage to limbs (where a prisoner struggles against his or her restraints in an attempt to stop the act or free his or her self), cause oxygen deprivation and can even result in death of the individual through dry drowning (where the lungs are unable to extract oxygen) or severe physiological distress.\n\nWaterboarding can also cause severe psychological distress, often lasting years after the event.\n\nWaterboarding is used as it is relatively easy to carry out, realistically only requiring a way to restrain a prisoner so that water accumulates on their face, cloth and a source of water to pour over that cloth. Waterboarding can also be drawn out over a long period of time which allows the interrogator control of the duration and the intensity in which it is carried out.\n\nThere has even been claims that a prisoner has been waterboarded so much that their electrolyte levels dropped to a dangerously low level resulting in the death of that prisoner, because of the amount of water used diluted this balance. This suggests that the technique can be used in a controlled fashion for days on end.\n\nElectrolytes allow our muscles and nerves to function correctly and without them causes serious problems. Electrolyte imbalances can become medical emergencies if left untreated.\n\nEven though a mock execution is highly psychologically damaging (using an unloaded firearm or one that is loaded with blanks) by climaxing extremely quickly and severely, it can't realistically be controlled in the same way that waterboarding can be.\n\nI would assert (from what I have read of the subject) that you could only pretend to execute a prisoner a finite number of times before the prisoner loses the will to live (since they have more or less hit rock bottom), whereas the amount and duration of pain (even though at a much lower level) that can be caused with waterboarding allows the prisoner to consider that his or her situation could get much worse.",
"It's a torture technique that simulates drowning and in meant to invoke a panic response. \n\n"
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
3bkdub
|
why do we need a "leap second" added to our clocks at the end of june?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3bkdub/eli5_why_do_we_need_a_leap_second_added_to_our/
|
{
"a_id": [
"csmxf9q"
],
"score": [
3
],
"text": [
"The Earth is very slowly slowing down. It takes a little bit longer to turn all the way around every time. In other words, over the course of a few years, a day becomes noticeably longer -- at least, noticeable to the super-advanced computers we use to coordinate our satellites and financial / telecommunication systems.\n\nSo, instead of changing the definition of a second every year (which would be a nightmare for programmers and pretty much everyone else as well), we just throw in a bit of extra time every once in a while to keep our clocks in line with the actual rotation and revolution of the Earth.\n\nIt's important to note that this is separate from leap years (where we add an extra day every 4 years) -- leap years are a way to make up for a fundamental error in early timekeeping that left a 24 hour day, made of 60 minute hours and 60 second minutes, a few minutes short of a whole day. Again, instead of changing all our clocks, we just agreed to add in an extra day on a regular basis to keep ourselves from getting too out of sync. Unlike leap seconds though, leap years are regular, repeating occurrences."
]
}
|
[] |
[] |
[
[]
] |
||
bi62rf
|
Do people who are born blind still experience REM when they sleep?
|
askscience
|
https://www.reddit.com/r/askscience/comments/bi62rf/do_people_who_are_born_blind_still_experience_rem/
|
{
"a_id": [
"em1qtzw"
],
"score": [
3
],
"text": [
"I was curious so I searched a bit. [Wikipedia says yes](_URL_2_) and cites\n\n > J. Alan Hobson, Edward F. Pace-Scott, & Robert Stickgold (2000), “Dreaming and the brain: Toward a cognitive neuroscience of conscious states”, Behavioral and Brain Sciences 23.\n\nGoogle finds the first 10 pages [here](_URL_0_). I don't find anything about blind people there with a quick search, but it looks like the pdf ends in the middle of the article.\n\nIf someone has access to the full article... _URL_1_"
]
}
|
[] |
[] |
[
[
"https://pdfs.semanticscholar.org/6ce3/50f101524afc3adf42012024d21b5bc75285.pdf",
"https://www.ncbi.nlm.nih.gov/pubmed/11515143",
"https://en.wikipedia.org/wiki/Rapid_eye_movement_sleep#Eye_movements"
]
] |
||
6751ju
|
how the anti-shoplifting vertical bars at stores' exits work (if you have no clue what i'm talking about let me know)
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6751ju/eli5_how_the_antishoplifting_vertical_bars_at/
|
{
"a_id": [
"dgnq5mk",
"dgoc730"
],
"score": [
7,
2
],
"text": [
"These panels are RFID detectors. Some valuable/high incidence of theft items have a little plastic tag attached to them, within which is an antenna and a programmable chip. If one of them gets too close to the panel's, they sound an alarm. They can be disabled by a strong magnet wiping them, which is why sometimes you'll see a cashier repeatedly wipe an item over a particular spot on the counter. ",
"There are two types of these. \n\nThe first is a passive one. Coils around those bars emit a radio signal at a specific frequency, and coils attached to products resonate (ring) at that frequency. This causes the way electricity flows through that coils to change in a way that is detectable. When you purchase something, either the tag is removed, or is disabled by a much stronger coil mounted in the counter, which provides enough energy to burn out the coil.\n\nThe second is an active one. There are transmitters and receivers in the bars, and a chip inside the tag on the product. The transmitters create a radio signal as before, and the tag's coils receive that signal, but here the signal provides power to the chip. The chip then transmits a number, which the receiver on the bars receives. The system knows when a number on a product should be in the store, and alarms. When you make a purchase, the tag is either disabled with a strong coil current as with the other type, or the cash register marks the number as sold, so the system knows not to ring the alarm."
]
}
|
[] |
[] |
[
[],
[]
] |
||
4198nc
|
mathematically, why can't a chair balance with 2 legs?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4198nc/eli5_mathematically_why_cant_a_chair_balance_with/
|
{
"a_id": [
"cz0j2pv",
"cz0j2yx",
"cz0kwtn"
],
"score": [
3,
7,
2
],
"text": [
"Mathematically it can. At the wonder spot. The \"house\" is built in a specific angle, on a specific slope, and one of the cool things they do there is put a chair up on a shelf, on two legs, and have people sit in it. ",
"To see if something will balance, lay a string on the ground around its feet and tighten it. (That's called the \"convex hull\" of the feet.) The center of mass must be above the area outlined by the string for it to balance.\n\nOf course when you tighten a string around two feet, it becomes a line with no area, which leaves a super tiny area that the center of mass must be in for it to balance.",
"With 2 legs, balancing is exactly what it's doing. Disrupt the balance with a shove, and it falls.\n\nWith 3-4 legs, balancing is no longer an issue. Push it one way or another , and it continues to stand."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
6f3wc5
|
How did the Roman Legions view eachother?
|
Was it like a rivalry between brothers?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/6f3wc5/how_did_the_roman_legions_view_eachother/
|
{
"a_id": [
"dif7nd6"
],
"score": [
6
],
"text": [
"As a followup question: during times of Civil War like Caesar's Civil War, did the opposing legions view each other like tragic brother vs brother (ex. USA Civil War) or did they view each other like good vs. evil (ex. Humans vs. Orcs)?"
]
}
|
[] |
[] |
[
[]
] |
|
38rz8s
|
why do some people's feet point straight while others have a "v" or "duck" shape?
|
Been wondering about this for a while. Is it a genetic thing? Is one better than the other? How does this affect the rest of the body?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/38rz8s/eli5why_do_some_peoples_feet_point_straight_while/
|
{
"a_id": [
"crxdj99",
"crxfbea"
],
"score": [
2,
2
],
"text": [
"There's [a whole wiki page](_URL_0_) about pigeon-toes, but I have no idea if there's a name for the-other-direction-toes. It says some of the causes are basically when your foot bones and/or muscles grow crooked; but that it usually corrects itself as you get older.",
"you see more V shape feet in people as they age. Has to do with tight (unflexible) hamstrings and calves."
]
}
|
[] |
[] |
[
[
"http://en.m.wikipedia.org/wiki/Pigeon_toe"
],
[]
] |
|
5ujjbj
|
why do we sometimes yawn and feel really sleepy, go to the bed but don't fall asleep as soon as we expected we would?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5ujjbj/eli5_why_do_we_sometimes_yawn_and_feel_really/
|
{
"a_id": [
"ddut9o0"
],
"score": [
25
],
"text": [
"Perhaps you are not distinguishing between \"sleepy\" and \"tired.\"\n\nFeeling **sleepy** is part of a physiological cycle. Your body clock is saying that \"now would be a good time to get the required amount of sleep.\" You do not necessarily have to have run out of energy at that point any more than you have to be starving to death before you feel hungry.\n\n**Tiredness**, however, is different. It is not part of a cycle and can be caused by a number of things: using up a lot of energy and not replacing it, lack of oxygen, boredom, illness.\n\nUnfortunately, the symptoms of both are similar and sometimes you can confuse the two. Yawning is frequently a sign of tiredness rather than sleepiness. Consequently you might go to bed thinking you are sleepy when in fact you are just tired (or \"fatigued\"). A few moments rest may be enough to replenish you energy levels and sleep is neither wanted nor necessary.\n\nJust to contrast the two:\n\nPeople can spend the whole day doing nothing but watch TV. Nevertheless, at a certain time they will fall asleep easily despite not really having tired themselves in the least. \n\nConversely, after, say, running a marathon, the runner is probably extremely tired but that doesn't mean that what he wants to do is curl up under the sheets and snore."
]
}
|
[] |
[] |
[
[]
] |
||
24m181
|
What causes tRNA to go from the cell nucleus to a ribosome?
|
I understand that protein synethsis occurs when a section of DNA is copied into RNA and this section of RNA then goes to a ribosome where protein synthesis occurs.
But what causes tRNA to go from the cell nucleus to a ribosome? I assume the main reason it leaves the nucleus is Brownian motion - it just is constantly being knocked by water and other small molecules, and there is just much more of the cell that is not nucleus than there is nucleus, so it will end up outside.
But what causes it to go to the ribosome? It seems a bit like hitting a bullsye by chance. IS there a chemical process at work? If so, what?
|
askscience
|
http://www.reddit.com/r/askscience/comments/24m181/what_causes_trna_to_go_from_the_cell_nucleus_to_a/
|
{
"a_id": [
"ch8hw0u",
"ch8j77n"
],
"score": [
2,
3
],
"text": [
"From your question, I think you mean, \"what way does a *mRNA* find the ribosome\", rather than \"what does a tRNA find the ribosome\n\nHowever, the answer is the same for both tRNA and mRNA - its still mostly brownian motion. Floating and bumping around at random, the mRNA will eventually leave the nucleus, and floating and bumping around, it will eventually hit one of the many ribosomes that are floating and bumping around in either the cell or the ER membrane.\n\nIt seems counter intuitive because we're often taught as if the cell is a great volume of water with rare macromolecules floating in it, but the inside of a cell is actually very densely packed. I forget the exact numbers, but of you work out a realistic estimate how long it takes, given stochastic movement, for a molecule of type \"X\" in a cell to come into contact with one of type \"Y\" (given the size of a cell, temperature, and relative density of \"X\" and \"Y\"), its on the order of milliseconds to seconds. Its a consequence of (1) the high # of molecules of any particular type in the cell, and (2) the relatively high speed at which Brownian motion of such molecules occurs at normal living temperatures",
"While a good idea, your hypothesis about Brownian motion is incorrect. t-RNA is exported from the nucleus via interactions with a cargo protein called Exportin-t (and some other related proteins).\n\nIndeed the vast amount of RNAs (mRNAs, tRNAs, pre-miRNAs) require interactions with similar cargo proteins (there are many exportins and related proteins) in order to traverse the nuclear pore. Export is tightly coordinated with transcription and correct processing (i.e. splicing, capping etc) to ensure a level of quality control (RNAs with the wrong assortments of factors will likely be noticed and trigger degradation pathways). "
]
}
|
[] |
[] |
[
[],
[]
] |
|
1mooc7
|
How did people deal with allergic reactions before epi pens? Did they just die? And how common was it?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1mooc7/how_did_people_deal_with_allergic_reactions/
|
{
"a_id": [
"ccb81z8",
"ccb8a68",
"ccb96qi",
"ccb9p17",
"ccbdl4g"
],
"score": [
199,
125,
104,
143,
15
],
"text": [
"If it was common to die from them, would that be an explanation for someone being \"struck down by God\"?",
"While I can't really say anything myself, I can direct you to two similar threads that have some answers you might find relevant.\n\n_URL_0_\n\n_URL_1_\n",
"[The phenomenon of anaphylaxis is old and has been described in ancient Greek and Chinese medical literature. The first documented anaphylactic patient might have\nbeen pharaoh Menes who died 2640 BC from the sting of a wasp, as hieroglyphs tell (Wadell 1930).](_URL_0_)\n\nThat's all I could find on this. I would hazard a guess that insect stings were a lot more common than food allergies back in that time so it may have been thought to be bad poisoning? \n\nEdit: Spelling",
"1) Alergic reactions - especially severe alergic reactions - appear to be more common place now than ever before.\n\nWhy this is can't be easily explained - better medicine **and diagnosis**, sure. Other environmental factors seem to have an influence as well (such as not introducing solid foods to babies until they are older, keeping a too clean a house etc.)\n\n2) People have only recently been able to get food or other possible alergins from around the globe.\n\nSay you were born in medieval Europe - no where near the ocean. How would you know that you had an alergy to shell fish if you had never eaten one?\n\n3) Yes, people did die - more often than not children. \n\nThis is possibly part of the reason the infant mortality rate used to be so goddam high.",
"This is coming from a layman, but [this Radiolab podcast](_URL_0_) talks about how certain parasites that we eradicated through hygienic lifestyle actually prevent a lot of allergic reactions."
]
}
|
[] |
[] |
[
[],
[
"http://www.reddit.com/r/AskHistorians/comments/1lhj0u/how_well_were_allergies_understood_by_regular/",
"http://www.reddit.com/r/AskHistorians/comments/1dejgs/woke_up_with_a_massive_sinus_headache_this/"
],
[
"http://media.wiley.com/product_data/excerpt/42/04708611/0470861142.pdf"
],
[],
[
"http://www.radiolab.org/story/91691-sculptors-of-monumental-narrative/"
]
] |
||
4k28la
|
Was there some kind of "newspaper" in ancient rome? Do we know how information and news usually spread throughout the empire?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4k28la/was_there_some_kind_of_newspaper_in_ancient_rome/
|
{
"a_id": [
"d3bs4nc",
"d3bswfq"
],
"score": [
66,
14
],
"text": [
"There were no newspapers, public or private, in the Roman world. The spread of information in the Roman world, to the extent that it was done through writing, was largely accomplished through posted notices. The most important of these, at least at Rome, were the *alba*, boards on which official notices were posted publicly within the city. Probably the best known of these is the praetorian *album*, on which the notices of the praetor were posted, but there were many different kinds posted by many different magistracies and carrying various sorts of official public information. These *alba* were generally lists, though, and often of a legal character, and you wouldn't find out what was going on in some faraway province by consulting them, though you could find the latest rulings of the law courts and the latest *leges*. Within the city information would also be spread orally, through *praecones* (basically criers) and other minor officials employed by magistrates, or occasionally by magistrates themselves at public assemblies of various kinds. Again, though, this was rarely \"news\" from throughout the empire, but really local (often legal) information and instruction. There was the daily publication of the *acta senatus* and the *acta populi*, the daily \"doings\" of the senate and the people respectively. This was introduced in 59 during Caesar's consulship, although Augustus forbade the *acta senatus* from being published. This was probably the closest thing to a newspaper in the city, being published daily and posted on tablets just like the rest of the *alba*, but it wasn't really like a newspaper as we know it. These were official notices, and they didn't really include what a modern paper would--Petronius includes a comic version of the *acta*, for Trimalchio's household, of which the following is an excerpt:\n\n > VII kalendas Sextiles: in praedio Cumano, quod est Trimalchionis, nati sunt pueri XXX, puellae XL; sublata in horreum ex area tritici milia modium quingenta; boves domiti quingenti. Eodem die: Mithridates servus in crucem actus est, quia Gai nostri genio male dixerat. Eodem die: in arcam relatum est, quod collocari non potuit, sestertium centies. Eodem die: incendium factum est in hortis Pompeianis, ortum ex aedibus Nastae vilici.\n\n > > July 26: At a Cumaean estate, belonging to Trimalchio, 30 slave boys were born and forty girls. Five hundred thousand *modii* [the number is comical--*milia quingenta* can mean literally five hundred thousand, or it can be \"a buttload,\" some enormous uncountable number] of wheat was taken from the threshing-floor to the granary. Five hundred oxen were broken. On the same day: Mithridates the slave was crucified, because he cursed the *genius* of our master Gaius. On the same day: ten million sesterces, which could not be invested, were placed into the safe. On the same day: there was a fire in the gardens at Pompeii, having arisen in the house of Nasta the overseer. \n\nPetronius says that it continued with a list of aediles' edicts, wills that Trimalchio was excluded from, the punishment of some of Trimalchio's slaves, etc. This is of course a parody, but it's easy to see that the *acta* weren't exactly the New York Times. \n\nThe *acta* were read in the provinces apparently, but there seems to have been no official system of actually distributing them. Official information was passed when possible by state officials, including the *viatores* and *statores*, minor officials whose duties might include acting as messengers. Even official information, however, was generally spread by private citizens (at least in the early Principate and the Republic--during the Principate a courier system for state documents began to develop), either the slaves or dependents of various magistrates or publicans and other tradesmen. For private correspondence and information the situation was not too different. The Roman state at no time had a postal service, and private citizens entrusted their letters to slaves and dependents or sometimes even to passersby and merchants--even Cicero talks about handing off letters to travelers and his friends' slaves. Of course, the army and other particular state functions had unusual access to information (the army, after all, or at least magistrates acting through the army, had the exclusive ability to send information by warship or military march), but of course the vast majority of people would have no access or interest in the information thus conveyed.\n\nMostly, however, information and news was spread orally. Obviously *praecones* and public speeches disseminated news orally, but what I mean really is by rumor. Ray Laurence had a good article a few years ago about rumor's involvement in politics in the city, and it's quite clear that a lot of information (political or otherwise) was spread by word of mouth. Candidates might have political pamphlets handed out or their supporters might [paint endorsements on the walls](_URL_1_) or [distribute objects through the city](_URL_0_) (those are bowls that Catiline used to support his candidacy), and magistrates and *praecones* might deliver public addresses, but really the access of the individual Roman to these means was pretty limited. Even within the city the average day-working laborer did not have the ability to miss a day's pay to go listen to a speech in a *contio*, and access became even more problematic as the provinces became more \"Roman\" and connected during the Principate, thus desiring the dissemination of more information at levels lower than provincial magistracy. Information was therefore spread orally, as people played a giant game of telephone throughout the city and eventually through the provinces. Precious information was made available to a certain few--those who had heard a magistrate speak in a *contio*, or had received a letter from the provinces talking about some event there, or had actually bothered to read what was on the *acta* and *alba*, or had been told by their patron that morning about this or that military victory or law to be brought to the assembly--and from there it was spread throughout the city (or the provinces, if we reverse this). ",
"There was no newspaper, since newspapers require a degree of mass literacy which was more than likely absent in the ancient world, and an inexpensive means of production. With no printing press or paper, there was no way a newspaper could be economically viable. News was spread largely by word of mouth, and in a variety of way. First, the men at the top of society kept in touch with each other through letters, and these usually passed along news along with other information of more personal interest. The best and most extensive example of this sort of thing is the collection of Cicero's letters. But other collections of letters exist from other time periods (Pliny for the early empire, Symmachus for the late) and show how letters could pass along news. Presumably merchants and other literate men from outside the very upper echelons of society kept each other informed through similar epistolary networks. \n\nOfficial news was passed along through ambassadors and letters as well. When a city wanted to request something of the emperor, they sent a citizen to ask him. The emperor then sent the ambassador back with a letter giving his response. We know of these because when the response was favorable the city often had the letter inscribed. At a more regional level, cities sent ambassadors to each other to announce local news all the time. There was constant stream of emissaries flowing back and forth announcing upcoming festivals or making requests for this or that. Once more, we know about these because cities often set up inscriptions honoring the men who had taken the time and trouble to go on these embassies. \n\nFinally, non-written communication, particularly through coins and monuments, was probably the best way to ensure a wide group of (often illiterate) people knew about something. So when Germanicus (the nephew of the emperor Tiberius) defeated the Germans in AD 19 and recaptured some of the legionary standards lost in the Battle of Teutoberg Forest in AD 9, coins were issued featuring Germanicus and the inscription \"the Germans have been defeated, the standards of have been returned.\" "
]
}
|
[] |
[] |
[
[
"https://upload.wikimedia.org/wikipedia/commons/thumb/c/c0/Cato_and_Catilina_propaganda_cups.jpg/1024px-Cato_and_Catilina_propaganda_cups.jpg",
"https://optimusmaximusadventurous.files.wordpress.com/2013/05/election-slogans-on-walls-pompeii-sramanujan.jpg"
],
[]
] |
||
7sm0u3
|
Did Robert E. Lee call for Genocide?
|
A Spanish-Language documentary on Netflix titled "Los Ninos Heroes de Chapultepec" features a collection of three Mexican and one American historian discussing the Mexican American War of 1846 to 1848. At one point, the American historian, John Mason Hart of the University of Houston, responds to a question about American attitudes during the war.
He says that "Some had very aggressive thoughts. Robert E. Lee, the future Commander in Chief of the Confederacy in the South during the American Civil War, wrote a letter that is now in Pennsylvania, saying that Mexicans should be thrown into the sea so that they could make this magnificent country our own."
I found this claim very surprising. It changes my whole image of Robert E. Lee and casts it into quite a dark perspective.
Can anybody here shed light on the letter that Professor Hart cited? Did Robert E. Lee really express such a sentiment?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/7sm0u3/did_robert_e_lee_call_for_genocide/
|
{
"a_id": [
"dt6u7dt"
],
"score": [
14
],
"text": [
"I'm afraid I can't address your main question vis a vis Lee's attitude toward Mexico and Mexican or Hispanic people, but I do have an [old write-up](_URL_0_) that touches on Lee's attitude towards slavery and people of African descent. It might help you to get a better grasp on Lee's mindset in general, and aid in understanding why many of the narratives that surround Lee's career try to downplay or hide that 'dark perspective' you speak of."
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/4g76bk/is_the_testimony_of_wesley_norris_authentic/"
]
] |
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