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5q0wxf
|
why would a president not choose cabinet members with longtime experience in that's cabinet's area of governance?
|
For example: someone with school administrative experience for Secretary of Education, someone with agricultural/geological experience for Secretary of Agriculture/the Interior, etc.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5q0wxf/eli5_why_would_a_president_not_choose_cabinet/
|
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"Usually that's what happens. However, Donald Trump is unique in his Presidency in that he's the first person in that office with no experience in either government or military. His experience is in business, and most in his circles have similar levels of experience. He's been picking people who are (usually) very wealthy and (usually) unqualified for the position in question, even to the point of holding views OPPOSITE to those intended for heading any given department. ",
"Qualified people will advocate for their agencies. They will effectively make the case for why their budget should not be cut and for the benefits of the work they do. Donald Trump does not want qualified people. He does not want people to advocate for their agencies. He wants people to head agencies that they clearly dislike, and whose traditional mission they disagree with. Hence, an advocate for charter schools as the head of education; an oil executive as head of the EPA, a staunch Obamacare opponent as head of Health and Human Services, a libertarian surgeon in charge of housing, etc... This is what anti-government looks like. ",
"Even when someone is nominated to a position with no experience in that specific area, they usually have\n\n * Administrative or management or oversight experience, and\n\n * A track record of public service, working in public interest, or at least working in the interest of a program or project that is not in their own interest in the financial or political sense.\n\nThis administration is almost certainly not going to be normal. Do not let yourself think otherwise.",
"The Republican Party literally wants to destroy many of those agencies. They don't like government as regulations and laws prevent them from using their wealth and power to become wealthier and more powerful. For example, the EPA works to make sure that greedy businesses don't destroy the environment and poison people in their pursuit of profit. So if the EPA is gone, they can mine and dig for oil and destroy the environment with much more freedom. There might be a lot of protests if they outright end the EPA and there are logistical issues against that. But if you pick someone who has great antipathy to the EPA, who has sued the EPA dozens of times when they've prevented him from raping the environment, then it's like giving the prisoners the keys to the jail. "
]
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5oz9vl
|
What were Hitler's ideas of succession? Who was to succeed Hitler should he die and what process would they have to go through to suceed as leader of his Reich?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5oz9vl/what_were_hitlers_ideas_of_succession_who_was_to/
|
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"_URL_0_\n\nUser u/searocksandtrees answered a similar question with a selection of answers from past threads. You should check them out. "
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[] |
[] |
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[
"https://www.reddit.com/r/AskHistorians/comments/34z3ar/what_were_the_plans_for_succession_after_hitler/?st=IY5CZNFL&sh=e2bf5995"
]
] |
||
yb87y
|
How do cells know what part of the DNA to read to function?
|
I'll phrase my question in the framework of a specific example. From my pedestrian knowledge of DNA, I believe my skin cells contain DNA which encodes the directions to produce all the cell within me. Now here's the question, how does my body know to produce more skin cells on my arm, rather than produce a nipple or something useless like that on my arm instead?
Would the analogy that my DNA is like a book with directions and somehow, some way my skin cells just skip over the chapters it doesn't need to read? The teeth, bone, heart sections of the DNA, it blows right past them and just dives straight into the skin section? That sound about right? If this analogy holds, how the hell does it know to do that? Because we all started as simple little balls of cells which were all pretty much the same, how does that become a person?
All this really segues into stem cells and what makes those things so damned special. Again from my simplistic view on things, I heard that they have the potential to be manipulated to become a variety of different cells.
Most of the things I've read just goes about tells you the typical stuff about DNA, how it replicates, chromosome crossover, double helix, c-t a-g, blah blah blah. But I haven't found out why your body doesn't go berserk and starts growing eye balls when your body is actually trying to grow hair. All the DNA is there for you cells to read but some how it doesn't do that shit. Though I believe that freaky shit happens in tumors, or in certain diseases, but I digress.
Any help would greatly be appreciated. And if I overlooked some article on line laying it all out for a working stiff as my self, than a thousand apologies for wasting everyone's time.
Thanks.
|
askscience
|
http://www.reddit.com/r/askscience/comments/yb87y/how_do_cells_know_what_part_of_the_dna_to_read_to/
|
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"There are regions in the DNA that attract or inhibit the enzymes which initiate transcription. These are known as promoters or suppressors.\n\nEdit: Also DNA packaging plays a role. There are 2 types of chromatin; heterochromatin and euchromatin. euchromatin is unwound and used in transcription, heterochromatin is condensed. As an example, the chromatin in a nerve cell would be packaged differently than that of a skin cell. This grants the transcriptional enzymes access to different regions of the genome for different types of cells.",
"Yeah pretty much you have it right. I mean it's a lot more complex than that but pretty much, the cell can skip over parts of the DNA that aren't needed. There's a whole subset of molecular biology that researches gene expression and how exactly cells do this. I'll try to give it a quick overview... \n\nFirst, you need to understand that a tiny fraction of the genome actually codes for the proteins. Around the coding regions are large swathes of DNA that are involved in regulation of a gene. The complexity of these regions is quite staggering. Basically, there are a host of proteins that bind to these regions -- these proteins are called \"transcription factors\" and enhance or suppress the binding of the cellular machinery to make an RNA molecule from the DNA (transcription). In a simple example, a transcription factor binds to a specific DNA sequence in the regulatory region of a gene and pulls with it the RNA polymerase to make an mRNA (thus turning on the gene). Sequence present, the gene is on, no sequence, the gene is off. There are hundreds of different transcription factors. They all can associate with other transcription factors, with different regulatory regions on the DNA, and with other parts of the cellular machinery and form intricate networks. They can enhance RNA production or suppress it.\n\nHow do these transcription factors come to be? Some of them are as the result of the cell sensing its environment, with signals transmitted through the cell membrane and down into the nucleus. Some are the result of intracellular processes, like knowing how far down a finger a cell is. Some are the result of developmental processes, like keeping track of how many cell divisions a cell has had. All of these signals get integrated on regulatory regions of genes.\n\nBut wait, there's more!. Just because the DNA is read out into RNA doesn't mean a functional protein will be made. In fact, only a minority of gene regulation occurs at the level of DNA- > RNA (transcription). At every step of the way, there are other regulatory points. The transcription factor may or may not be able to bind to the DNA because the DNA may be modified or packaged in a way leaving it inaccessible (or more accessible). The RNA can be processed at a number of different pathways, and some RNA is more stable than others. Then there are boatloads of RNA- > protein regulatory steps as well, as well as boatloads of protein processing steps.\n\nStem cells are special for a number of reasons. But needless to say, for most cells, there are certain checkpoints of development that once passed, cannot be easily reversed. The lineage of that cell becomes restricted -- for instance liver cells can beget liver cells but not other cells (easily). \n\nMost cells in the body have passed so many checkpoints and have become so specialized that they generally don't divide at all anymore, and there are organ-specific stem cells that repopulate the tissue. For instance, you have basal cells in the skin that divide to form new skin cells. The stuff at the surface and even a few layers below is dead or dying. These are one kind of stem cell, but a limited stem cell. \n\nThe kind of stem cell that people get super excited about are cells like this that can not only form skin, but lungs and liver and maybe even blood or blood vessels. We call this \"pluripotency.\" If we could grow these in a dish, we could feed them the right signals and turn them into the tissue of our choice. Anyway, you (hopefully) get the picture.\n\nninja edit for clarity not that it helped\n\nedit 2: lemme also just add that your OP makes it seem like DNA is read in some sort of linear fashion, like a book. The DNA in the nucleus is much more like a tangled ball of string than a strip of code. All of the DNA is exposed to all of the transcription factors. Essentially, the cell is reading ALL the DNA at the same time and making decisions as to whether a gene is on or off. ",
"Your DNA is wound up in a mass in most cells- like a ball of string.\nSo how do the proteins know which part to read first ?\n\nThere are proteins that can unwind the DNA at specific points during the cells life cycle, and let the DNA get copied into RNA. RNA is like a photocopy of DNA that the cell can send out of the nucleus to the parts of the cell that actually make proteins.\n\nThere are \"promoter\" sequences on the RNA, which can attract ribosomes. During different growth situations, some promoters are good at attracting ribosomes, and some are [bad] (_URL_1_)\n\nSo how do cells know what the right messages are ? How do they know whether to turn into an anus or an elbow.\nYour cells are always in communication with eachother throughout growth. When you are developing as an embryo, cells that will form the top part of you will start sending out chemical messages saying it's the top part, and that the bottom is the bottom. \n\nThese messages causes certain genes in the DNA of the cells of the bottom segment to activate. These will cause more chemical messages to be sent out over a shorter distance, saying what sort of organs the cells will divide into.\n\nYou may find this video useful\n_URL_0_\n",
"Short answer: This is due to epigenetic information.\n\nDNA sequences are chemically modified, sometimes in a heritable manner and some due to environmental signaling. These markers signal proteins which pack, and thereby silence, or open unneeded and needed regions of chromatin accordingly. That, along with conformation changes, shifts active regions of DNA to co-localize in transcription factories - regions in the nucleus where appropriated machinery to translate DNA to RNA resides and co-factors conspire to regulate activity.\n\nDisclaimer: regulation of gene expression is an actively researched field. We don't know everything. What i describe is what i understand is currently the accepted model in the field.\n\nSource: I am a computational biologist studying chromatin conformation",
"First thing to remember is that this isn't designed. So a question about \"how does it know\" may be difficult to answer or disappointing. There is no brain making decisions within the cell, and we're talking about a chemical reaction that has been continuing uninterrupted for billions of years. Not \"reactions like this one\" - this exact one. The cause of anything that looks like an intelligent decision about what to execute is just another piece of DNA that was executed because of another piece of DNA... just molecules touching each other in specific ways all the way back to the first nucleic acid.\n\nThe second thing to remember is that if a DNA mutation is a rare accident, a mutation that impacts anything but the physical genome is an accident among accidents. Given that it's the first order mechanism of evolution, it would be reasonable to assume that what you're asking about is more complex and finely tuned than the sum total every other biological process that we are aware of. \n\nThat being said, certain mechanisms have evolved to increase the chance that a given mutation both (a) makes a change outside the genome itself and (b) does so in a coherent way that has any chance at all of being helpful. (a) requires some sort of positive feedback mechanism, (b) requires some code re-use. \n\nOne good one to look at is the [Hox Gene](_URL_0_), which appears to be some sort of cloning GOTO statement. Hox going active among cells in a certain region can make an entire arm or eye appear. A mutation that activates it in the \"wrong\" place can make a functional extra limb appear.\n\nAnother good one to look at is [Morphogen](_URL_1_). To break the initial symmetry, the fertilized egg has concentration gradients. The egg cell grows and builds internal walls to split, and the gradients cause the daughter cells to have different concentrations of various molecules - purely because of how they get physically trapped by the membrane. Different concentration levels in each daughter cell trigger positive feedback mechanisms to bootstrap specialization. These feedback mechanisms must be sensitive enough to concentration to cause the cells to execute the correct routines, but not so sensitive that a slight change in chemistry makes the process fail in any of the initial cells. These routines, hooks, and feedback loops are some of the most critical for multi-cellular life - if you don't get this part right, nothing else matters."
]
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"http://1.bp.blogspot.com/-6TNLHL69pWE/TwiXgaaSfPI/AAAAAAAAAQg/0XwEhxHzbcs/s400/promoter.png"
],
[],
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"http://en.wikipedia.org/wiki/Hox_gene",
"http://en.wikipedia.org/wiki/Morphogen"
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|
1lj5hx
|
why is it that most game developers don't include/allow modding support, when many other franchises are successful because of it?
|
Minecraft, fallout, skyrim, kerbalspaceprogram and arma are games that become extremely popular because of their ability to mod, and their devs all encourage modding, yet many larger devs are strongly against it. Especially in Arma's case, modding increased their sales and replayability, so why don't other companies allow it?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1lj5hx/eli5_why_is_it_that_most_game_developers_dont/
|
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"If it's mostly/entirely played on console, there's no point. Even if it's not there's the fact that modding tools can be a bitch and they don't predict enough of a payout in extra sales to cover those costs."
]
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[] |
[] |
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mjxd5
|
Sound and Waves: How does a magnet pick up sound in an electric guitar?
|
Can anyone explain in detail how sound leaves the strings, gets picked up by a magnet, travels through a cable to be amplified? Thank you
|
askscience
|
http://www.reddit.com/r/askscience/comments/mjxd5/sound_and_waves_how_does_a_magnet_pick_up_sound/
|
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"The strings are made of steel, right? So the magnet is attracted to the steel string. As the steel string vibrates up and down it pulls on the magnet up and down. And that vibration of the magnet inside of coils of wire (pick up coils) generates a small amount of voltage that has a waveform directly correlated to the vibration of the string. That voltage travels down the wire as a current, gets passed through an amplifier then around another coil with a magnet inside *that*. And as the current in the wire changes, it creates a magnetic field that vibrates the magnet inside of that coil, and that magnet is usually attached to some paper cone that then pushes air back out as sound waves. And that, my friend, is how electric string instruments work. (more or less, really there's a lot of other things, like multi-coil/hum-bucker pickups that eliminate stray EM interference, passing the current through some sort of distortion circuit to produce cool effects, non electromagnetic pickups like lasers or piezoelectrics, etc.)",
"The strings are made of steel, right? So the magnet is attracted to the steel string. As the steel string vibrates up and down it pulls on the magnet up and down. And that vibration of the magnet inside of coils of wire (pick up coils) generates a small amount of voltage that has a waveform directly correlated to the vibration of the string. That voltage travels down the wire as a current, gets passed through an amplifier then around another coil with a magnet inside *that*. And as the current in the wire changes, it creates a magnetic field that vibrates the magnet inside of that coil, and that magnet is usually attached to some paper cone that then pushes air back out as sound waves. And that, my friend, is how electric string instruments work. (more or less, really there's a lot of other things, like multi-coil/hum-bucker pickups that eliminate stray EM interference, passing the current through some sort of distortion circuit to produce cool effects, non electromagnetic pickups like lasers or piezoelectrics, etc.)"
]
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18gjdv
|
How much water evaporates in an underwater nuclear explosion?
|
I don't even know where to start. Since it probably depends on the specific device, let's go big... Tsar Bomba.
|
askscience
|
http://www.reddit.com/r/askscience/comments/18gjdv/how_much_water_evaporates_in_an_underwater/
|
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"Well, according to Wikipedia, the Tsar Bomba produced 240PJ, or 2.4x10^17 J. It looks like it was detonated over land, but we can ignore that and have some fun. If we make an assumption that ~10% of its energy is absorbed by the water, that would mean 2.4x10^16 J. If the water temp is 20ºC, it would mean that it would have enough energy to boil 9.25x10^9 kg of water, or 9.25 million cubic meters. That's a lot of water."
]
}
|
[] |
[] |
[
[]
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drzthi
|
how exactly does sinus pressure build up when sick and why?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/drzthi/eli5_how_exactly_does_sinus_pressure_build_up/
|
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"If an infection reaches your sinuses it will cause inflammation and increased mucous secretion. This increased secretion together with the inflammation can clog the sinuses and thus lead to increased pressure and pain.",
"Imagine your sinuses are a water balloon. When it is empty it is all floppy because there isn't anything pushing on the sides of the balloon, this is a lack of pressure. When you fill the water balloon the water pushes on the insides and gives it a shape from the pressure. \n\nNow when you are sick your sinuses are filling with fluids, and the lining of your sinuses are thickening due to immune cells coming to fight the infection. There is a lot of pressure, but no where to go and this pushes on some nerves that cause an unpleasant feeling."
]
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[],
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4d8b82
|
how did the north star happen? does every star revolve around it?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4d8b82/eli5_how_did_the_north_star_happen_does_every/
|
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"It's a star that happens to be mostly aligned with the Earth's axis. Watching from the surface, as the planet spins the star looks like it's stationary.",
"It is not a special star, and no stars revolve around it.\n\nBy dumb luck, our planet's north pole just happens to point at that particular star. So as we spin, the other stars appear to be moving (it's really us), but that one sits at the center.",
"The earth rotates, and its rotation is stable and predictable. It seems to rotate around an imaginary line through it, which we refer to as its axis. The axis of the earth is fairly close to the magnetic north and south poles, though not perfect. So imagine the north pole as the end of that axis, and imagine it as a big arrow pointing.\n\nIt just so happens that that arrow points to Polaris, the north star. No matter how the earth turns, that \"arrow\" points in the same direction, and there happens to be a star where it's pointing. This is a big coincidence. The other stars, the sky, they're not moving, at least not in a way that explains the \"motion\" we see. All of that movement is the earth and the moon. \n\nHowever, the axis not as steady as it looks like to us. Every piece of scientific writing I've seen on this topic suggests that the axis is actually slowly \"wobbling,\" and will eventually move just enough that it no longer points to Polaris. Eventually, it'll point to another star instead, and that will be the north star. That won't happen in our lifetime.\n\nBut essentially, our planet just happens to be pointing its rotational axis at a random star in the sky. ",
"No. The stars don't revolve around each other. They surround the earth, and the earth just rotates. \n\nTry this as a thought experiment: Imagine sticking those glow in the dark star stickers all over the walls of your bedroom, and then sticking the last star on the ceiling right above your head. Now you spin around on the spot. The stars on the wall will look like they're whizzing by you. But if you look up at the one above your head, it'll look like it's stationary. That's the north star. It sits \"above\" the earth relative to the axis it spins on. "
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3u20gf
|
US Congressional Uses of Sanctions Against a Foreign Nation? [research question]
|
Hello, I hope this is the correct place for this.
I'm **researching events surrounding the repeal of Apartheid in South Africa from a US foreign policy perspective**, and I read that when US Congress passed the Comprehensive Anti-Apartheid Act in 1986, it was a **rare event for congress itself to impose sanctions** rather than leave that to administration officials. I know that congress has done so more recently against Iran, but I'm having **difficultly locating older historical examples** to compare the CAAA to, or any kind of database of congressional uses of sanctions. [This website](_URL_0_) is probably the best I've found, with links to full text of relevant acts passed and enough context I could do a thorough search, but really only deals with Iran and briefly Libya, not even going back to the CAAA.
Ultimately, if there is suitable evidence, questions I would like try to answer is "why are/were these uses of sanctions rare, are they significant to achieving their goals (efficacy), is there a theory that explains why the CAAA was passed (predictability), is that theory more relevant to domestic or international inputs, can the theory potentially predict situations were a legislative sanction is likely to be used again (and because I have data for this, I can test for this), if so when is another use likely, if not what changed?"
(On a side note, the US foreign policy towards South Africa from the Kennedy administration on is pretty funny, in its complete ineffectiveness, two faced goals and disregard of the blatant human rights violations. Part of the reason CAAA was passed was because of how poorly the situation had been handled, and I really want to know if the foreign policy contexts are always as poorly managed.)
**If anyone knows more about this admittedly narrow topic, or has read anything related, or can otherwise point me in the right direction (or just wants to talk about my research) I would appreciate it.** As it stands the CAAA isn't particularly important in my discussion, so I won't be heartbroken if its a dead end, but for some reason an off-hand remark I couldn't verify about the rarity of a questionably unimportant legislative event sparked my interest. Now I want to learn more about it.
Also, if you do know more about the situation at large feel free to bring up other interesting related topics of history or politics. I'll be honest that I don't fully understand the contemporary South African domestic issues (outside of the obvious), or how much of a role Cold War tensions played (outside of Angola). I'm sure there are many factors I have not yet considered, and discussion always helps me decide how much to hone or widen an argument.
I guess I should also say this is for a class, so I'm not looking for easy answers, but **more avenues of research**. Perhaps there's a key term I haven't found that would find the correct results, as so often happens when researching weirdly specific things. I also hope it is okay I'm asking on this sub in an academic context. I couldn't think of anywhere else that would be able to help with problem like this, and normally in this situation I'd just ignore the question, but I really don't want to let this one go yet. If there is a better place to ask this, or if I need to change the format to conform with subreddit standards, please let me know.
I could talk about this all day (apologies for the text wall), so if anyone wants to know more about the topic or the works I've read thus far, shoot.
tl;dr: Important stuff in bold.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3u20gf/us_congressional_uses_of_sanctions_against_a/
|
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"As you might guess from the flair, my speciality is labour history, so I can only offer you limited assistance with finding material that will help develop your thesis. Nonetheless, I have done quite a lot of work on South Africa, so I'm going to try and help point you in the direction of some useful resources.\n\nIt seems to me that the most obvious historical example of sanctions being imposed by the United States on another nation before the CAAA would be those imposed on Cuba in the 1960s; I'm not familiar with the legislative framework surrounding the Cuba embargo but I'd be surprised if it wasn't worth chasing up. You may want to take a look through Appendix I of the Foreign Assistance Act (pp1,015 - 1,035), which you can find [here](_URL_1_) and which runs right back to the Trading with the Enemy Act of 1917, though it is not a comprehensive list of sanction-related legislation (the CAAA isn't in there for one). The Department of the Treasury website has a summary of [ongoing sanctions](_URL_2_) enacted by the United States.\n\nAnother obvious point of comparison and one extremely relevant to your inquiry would be the sanctions imposed on Rhodesia - or Southern Rhodesia as it is sometimes referred to after its British colonial name, present-day Zimbabwe - after it declared independence from the United Kingdom. As I understand it, sanctions on Rhodesia were imposed by the President rather than Congress but became a battlefield in the 1970s, after Harry Byrd Jr. succeeded in tabling an amendment to another bill allowing imports of chrome from Rhodesia. CQ Alamanac have a [contemporary article](_URL_4_) outlining the legislative battle that you might find useful. I think the Rhodesia debate could be very useful for you.\n\nIn terms of finding primary source material, I'm going to assume that you're based in the United States rather than South Africa - if I'm wrong, do correct me! I think the best resource you can use for primary sources is going to be JSTOR's *Struggles for Freedom* collection (formerly known as the Aluka Project), which you can access [here](_URL_0_). It is filled with useful source material, and I know there are definitely congressional reports and documents in there relating to US foreign policy in southern Africa, including sanctions.\n\nYou may also want to check out the [African Activist archive](_URL_5_), which is focused on the anti-apartheid movement and probably has some relevant documents that may assist you. For material on a South Africa perspective, the [University of KwaZulu Natal's digital archive](_URL_3_) is an *incredibly* valuable resource for anyone unable to go to South Africa. Unfortunately, its search function is appallingly awful and UKZN's servers are about as modern as apartheid itself, so the website is frequently down. There may nonetheless be material in there relevant to your topic.\n\n > I'll be honest that I don't fully understand the contemporary South African domestic issues (outside of the obvious)\n\nIf you're looking for an overview of South African economic history, Sampie Terreblanche's *A History of Inequality in South Africa, 1652 - 2002* is perhaps going to be the best single volume for a broad, sweeping look at the dynamics of racial and economic inequality. It's a very political work and its conclusions about the post-apartheid period are controversial (and, in my view, based on some deeply flawed assumptions about a few particular aspects of South African history - but about things quite peripheral to your topic), but it's certainly still a good book on the whole. It doesn't sound like you'll need to be talking in much depth about South Africa itself, and so might be useful for getting a broad understanding of the context without getting bogged down in historiography.\n\nI hope that some of this is helpful for your research; hopefully someone else will be able to come along and offer other insights or advice. Do let me know if there's anything else you think I might be able to help with."
]
}
|
[] |
[
"http://www.defenddemocracy.org/us-sanctions-legislation/"
] |
[
[
"http://www.aluka.org/struggles",
"https://www.usaid.gov/sites/default/files/documents/1868/faa.pdf",
"https://www.treasury.gov/resource-center/sanctions/Programs/Pages/Programs.aspx",
"http://www.disa.ukzn.ac.za/",
"https://library.cqpress.com/cqalmanac/document.php?id=cqal77-1202677",
"http://africanactivist.msu.edu/"
]
] |
|
3m53ei
|
Why did the number of African American voters in the presidential election steadily decrease after the passage of the Voting Rights Act of 1965?
|
_URL_0_
This NY Times article indicates that African American election turnout dipped after 1964, and did not exceed 60% until 2008. What are some possible reasons for this decline from '68 onward?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/3m53ei/why_did_the_number_of_african_american_voters_in/
|
{
"a_id": [
"cvc4jna"
],
"score": [
9
],
"text": [
"One variable you're not taking into account is that voter turnout for *all* Americans was [steadily going down](_URL_0_) during this period. Whereas the percentage of the voting-age population who participated in the 1960 election was 63.1%, [by 1996 that number had fallen to 49.1%](_URL_2_).\n\nIn point of fact, the gap between the participation of black and white voters has steadily been [narrowing since the passage of the Voting Rights Act](_URL_1_):\n\n > ...the racial gap in voter registration in former Confederate states shrank from nearly 30 percentage points at the start of the 1960s to 8 points by the start of the next decade.\n\n > Turnout in the South saw a similar reversal. In 1956, voter turnout among blacks in once-Confederate states was roughly 50 percentage points lower than that for whites. That gap has narrowed since the Act was passed and Southern black turnout has been higher than white turnout in four of the 12 presidential elections since."
]
}
|
[] |
[
"http://www.nytimes.com/2014/10/17/upshot/black-turnout-in-1964-and-beyond.html"
] |
[
[
"http://i.imgur.com/IwvtzbQ.png",
"http://www.washingtonpost.com/blogs/govbeat/wp/2015/03/03/where-black-voters-stand-50-years-after-the-voting-rights-act-was-passed/",
"http://www.infoplease.com/ipa/A0781453.html"
]
] |
|
6xf8kl
|
why are old people so small and short?
|
They seem to just become shorter and shorter
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6xf8kl/eli5why_are_old_people_so_small_and_short/
|
{
"a_id": [
"dmfm0fo",
"dmfoqyk",
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"score": [
19,
11,
3
],
"text": [
"Gravity. As people age, their bones start to lose mass, their spine begins to collapse on itself and there's usually less muscle mass. At least that's what my doctor tells me to explain why I'm nearly a half inch shorter than I was 40 years ago.",
"There are two factors at play. \n\n1. As you age, gravity and cell degradation take a toll. [For every decade over the age of 40, you lose about 4/10 of an inch (1 cm) of height](_URL_1_) due to the soft cushioning tissue in your spine compressing. The bones themselves can also shrink if you have osteoporosis.\n\n2. Older generations, up until around the 1970s (in the US), [just did not grow as tall](_URL_0_). This doesn't necessarily apply to all countries (some places, like Egypt, have seen the average adults shrink over the past few decades), but it is a wide general trend across the globe. This simply comes down to better average health and nutrition, since being malnourished, sick, or just having a bad diet as a kid (especially during teenage years) can lead to you not growing as much as you would otherwise. ",
"Old people experience sarcopenia as they age, which is a form of muscle loss. As the get weaker they often develop poor posture. Poor posture along with osteoporosis and degenerating vertebral disks decreases their affective height. Lifting weights can help with all of these factors except maybe disk degeneration. The main factor limiting their height is posture.\n\nBasically they lose muscle, the squishy disks in their spine get worn out, and they're bones get brittle and worn down. "
]
}
|
[] |
[] |
[
[],
[
"http://www.npr.org/sections/goatsandsoda/2016/07/27/487391773/americans-are-shrinking-while-chinese-and-koreans-sprout-up",
"http://www.nytimes.com/2013/01/03/booming/why-am-i-getting-shorter-with-age.html"
],
[]
] |
|
9s7x8x
|
What are the most revealing statistics that show the overwhelming progress made by modern medicine?
|
askscience
|
https://www.reddit.com/r/askscience/comments/9s7x8x/what_are_the_most_revealing_statistics_that_show/
|
{
"a_id": [
"e8o5fxp"
],
"score": [
2
],
"text": [
"My area of expertise is cancer statistics. By far, the most progress we’ve made is with childhood cancer. In the 1950s, fewer than 20% of children diagnosed survived more than 5 years. Today survival is over 80%. I’d still love to see that number rise, but I think our progress is astounding.\n\n[Childhood cancer survival by site and year](_URL_0_)"
]
}
|
[] |
[] |
[
[
"https://i.imgur.com/cJRZh9A.gif"
]
] |
||
4b41zu
|
why is the combo of ibuprofen and alcohol so bad for you?
|
Is it simply a question of the liver not being able to filter as much toxins if it is already busy with ethanol or do the 2 react with each-other somehow?
Also if I do take an ibuprofen (500mg) while wasted and keep drinking beer for example, how much liver damage does that combo do?
Edit// was talking about Solpadeine, my bad.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4b41zu/eli5_why_is_the_combo_of_ibuprofen_and_alcohol_so/
|
{
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"d15vh7r",
"d15vjio"
],
"score": [
7,
2
],
"text": [
"I believe you're confusing ibuprofen with acetaminophen. Acetaminophen is associated with liver and kidney damage when consumed with alcohol. To my knowledge ibuprofen is not. \n\nAcetaminophen is also known in some countries as Paracetamol. \n\n_URL_0_\n",
"It's acetaminophen (Tylenol) that doesn't mix well with alcohol. This is because both are metabolized in the liver. The liver can't handle both at once so you end up damaging your liver and having a more pronounced effect from the alcohol. \n\nIbuprofen (motrin/advil) is metabolized in the stomach and generally doesn't interact with alcohol. "
]
}
|
[] |
[] |
[
[
"http://www.m.webmd.com/a-to-z-guides/news/20131104/tylenol-and-alcohol-a-bad-mix-study-suggests"
],
[]
] |
|
2u6w3n
|
what needs to happen for a plane to fly into other countries' airspaces?
|
When a plane crosses another country's airspace in its journey, what happens? Does that country's air force get all airplane schedules of the day ahead of time and verify that? Or is there a database of planes flying that we don't know about?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2u6w3n/eli5_what_needs_to_happen_for_a_plane_to_fly_into/
|
{
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"co5nzoa",
"co5p63h",
"co5paew",
"co5rbk2"
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"text": [
"If it's playing nicely then it will have a filed a flight plan and be carrying a transponder which identifies it, so air traffic control are expecting it and know which plane it is when it appears on their radar.\n\nIf not, and it doesn't respond to air traffic control asking what it's doing, then fighters would be scrambled to go and see what it is, and eventually shoot it down if the appearance of fighters doesn't make the pilot more talkative.",
"Airlines negotiate air travel routes with the countries over or into which they fly. They usually pay a route fee for each route, or for each plane on the route. If you don't have a paid route, ATC will not approve the flight plan and you won't be cleared into the airspace. The rules are slightly different for GA than commercial. ",
"Navy Air Controller here, we frequently send organic aircraft ashore into different countries. Basically, we search for the contact information for the appropriate controlling agency (Air Force or ATC as an example). We establish a flight plan, from where ever we are into their controlled airspace. Upon launch, I instruct the aircraft to notify me when they have two way communication with whatever controlling agency and then I release control to that agency.\n\nIf there is something like an ADIZ (Air Defence Identification Zone) then my aircraft might be challenged if no flight plan has been filed. Prior to launch, we will generate an ADIZ Penetration message, notifying the appropriate authority that our aircraft will be entering such and such a place at whatever time.\n\nIn a nutshell.",
"It depends. The general idea here is the [freedoms of the air](_URL_0_), some of which are pretty universally established by treaty and some of which aren't.\n\nMany countries allow any other country's airlines to fly over without stopping (the big exceptions are Russia and Canada, which require you to negotiate for permission, because a lot of flights pass over those two on great-circle routes), and simply charge the airline a fee to cover the cost of things like operating air traffic control services.\n\nFor flights by Country A's airline which fly to/from Country B, typically an explicit negotiated agreement is required. Country B will grant Country A a certain number of takeoff and landing \"slots\", and Country A's aviation authority will portion them out among Country A's airlines. For example, right now there's a slot at Tokyo's Haneda airport that's sort of up for grabs among US airlines: Delta had the slot but isn't really using it, so American Airlines, United and Hawaiian are all trying to get it."
]
}
|
[] |
[] |
[
[],
[],
[],
[
"http://en.wikipedia.org/wiki/Freedoms_of_the_air"
]
] |
|
1rk7o8
|
Would a SETI program located in the Alpha Centauri System be able to detect radio signals from Earth?
|
-
|
askscience
|
http://www.reddit.com/r/askscience/comments/1rk7o8/would_a_seti_program_located_in_the_alpha/
|
{
"a_id": [
"cdo7e79"
],
"score": [
16
],
"text": [
"Let's say a station is broadcasting at a full Megawatt of power (the strongest, to my knowledge are usually in the half-megawatt range). Let's say they have a dish (or array of dishes with equivalent collection area equal to) of *d* meters in radius. Their collection area is pi *d*^2 , but our signal is spread out over the sphere of 4.24 light years, that's about 4 x 10^16 meters. And the surface area of a sphere is given by 4 pi r^2 , so 6.4 x 10^33 pi meters. So the signal strength is approximately their collection area divided by the surface area of the sphere, so about d^2 / 6.4 x 10^33 . \n\nSo there's a factor of 1.5625 x 10^-34 reduction in signal strength. A megawatt is 10^6 , so that leaves us 10^-28 . d^2 / 10000 Yoctowatts of power (we don't even have an SI prefix small enough to properly label it). \n\nSo now, looking at wiki's orders of magnitudes of power, the Galileo satellite was giving a 70 m pickup about 10^-21 (zeptowatt) of power. So let's say that the alien SETI program needs to pick up .1 zeptowatt (to make the math easy). So it needs 10^3 yoctowatts, so d^2 = 10^8 , so d = 10^4 , they'd need something like a 10 kilometer dish to pick up our signal. Given all the above approximations, their dish maybe needs to be between a kilometer and 100 kilometers, just to be safe. \n\nSo not *impossible* but seems like just barely possible. Certainly more distant objects are going to have even more trouble (remember again that signal decreases with square of distance)"
]
}
|
[] |
[] |
[
[]
] |
|
2vpiv3
|
During the times corsettes where worn where they worn during pregnancies as well? Is it known how a life of wearing corsettes affected pregnancies?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2vpiv3/during_the_times_corsettes_where_worn_where_they/
|
{
"a_id": [
"cok1gxl"
],
"score": [
2
],
"text": [
"hi! not discouraging other responses, but there was a similar question a month ago that's worth checking out\n\n* [Did pregnant women wear corsets in the Victorian era?](_URL_0_)"
]
}
|
[] |
[] |
[
[
"https://www.reddit.com/r/AskHistorians/comments/2s6hm8/did_pregnant_women_wear_corsets_in_the_victorian/"
]
] |
||
50nzoe
|
Why do stable compounds react?
|
First of all, correct me if I am wrong. Isn't the initial motive for an element to react with another, to obtain lower energy level/relatively more stable state by staying together so the atomic orbitals overlap (co-valent or ionic bond depending on the electronegativity difference)? So why do stable compounds react and form different - even higher energy compounds?
Fore example substitution reaction mechanism presented like this:
Step 1. R-Cl ----- > R⁺ (carbocation) + Cl⁻ (halogen ion)
Step 2. OH⁻ + R⁺ ----- > R-OH
Why does chlorine leave the alkene when it has satisfied octet rule and obtained stable state in the molecule? Does bringing energy to the system make chlorine vibrate so much that C and Cl's orbitals no more overlap and thus Cl "flies away" with sigma-bonds electrons (Cl⁻)?
First and foremost is that the case with every non-spontanious reaction - bring energy to system to break stable bonds in molecules then in presence of different elements that molecule will make relatively higher energy bonds to satisfy the lack of electrons or attract element/compound with it's extra free electron pair or radical?
|
askscience
|
https://www.reddit.com/r/askscience/comments/50nzoe/why_do_stable_compounds_react/
|
{
"a_id": [
"d76u6vn"
],
"score": [
3
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"text": [
"The key here is that \"stable\" is just a relative term. Thermodynamically, there MUST be an equilibrium between association and dissociation of a bond like R-Cl. Bringing energy to the system amounts to tilting the equilibrium closer towards the dissociated side. But it's still only a small fraction of the total number of molecules.\n\nWhat happens next is why we have a reaction that has a direction and some yield. A given cation R+ floating around at any time could simply encounter a Cl- and go back to R-Cl. Or, if we have a lot of OH- in the flask, it could encounter an OH- anion and form R-OH.\n\nR-OH is also in equilibrium with R+ and OH-! But R-OH is more stable (relative term) than R-Cl. So we've effectively formed a trap: it's much less likely that a molecule of R-OH will dissociate and go back to R-Cl than R-Cl to R-OH. Especially given that we typically add an excess of OH- and we only have a small amount of Cl- at any time."
]
}
|
[] |
[] |
[
[]
] |
|
4gis1q
|
What do antivirus scanners on your PC actually look for in a file?
|
Obviously they search for a virus but what attributes of a file gives away thats its a threat to the system?
|
askscience
|
https://www.reddit.com/r/askscience/comments/4gis1q/what_do_antivirus_scanners_on_your_pc_actually/
|
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21,
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"text": [
"Virusscanners use two approaches: Signature-based scanning and heuristic scanning.\n\n**Signature-based** scanning involves looking for specific elements in a virus program. Some virus authors in the past left messages in their program which could be scanned for. Alternatively, certain filenames were used. Or simply the entire file contents (or a hash value thereof). The idea is that the developer of the virusscanner receives a new virus-program and adds its signature, whatever it is, to the scanner definitions. \n\nThe downside of this is that virusscanners will always be one step behind virus creators, since the scanner can only respond to threats that it has been programmed to recognize. Additionally, some virus developers will incorporate code to change the virus software automatically when it spreads, making signature-based recognition much harder.\n\n**Heuristic** scanning on the other hand looks at the behaviour of a program. It scans the file in order to see which instructions it contains and then matches that with sets of instructions that are considered harmful. For example instructions that exploit a known software bug in order to obtain administrative privileges.\n\nHeuristic scanning can detect new viruses that haven't been identified before. It's also more effective against malware that modifies itself automatically. On the other hand, if the scanner is tuned too aggressively, it could get many false positives. Tune it too passively and viruses that don't behave too badly will slip by it. Heuristic scanners don't need to be updated as often (though they still need updates, because virus behaviour changes over time).\n\nMost scanners use a combination of both techniques. Signature-based scanning is primarily aimed at spotting known threats, while heuristic scanning offers some level of defense against new ones. Some scanners also include features that monitor access to certain system resources (such as the Windows Registry) and will warn the user when a program tries to access a monitored file or system.",
"There is also behavior based protection, which is sort of a grey area. It doesn't target viruses specifically, but can detect patterns that may lead to potential infection.\nIt's common with an IPS to notice things such as port scans, which could be someone looking for a way in to do damage.\nIt's virus protection in a round about sort of way.\n=2c",
"The other comments are a great description of what your antivirus program is probably doing to detect malicious programs.\n\nI also wanted to point out a developing approach from the machine learning community. The way that an email company filters out spam is to look at different features of an email (e.g. individual words, phrases, sender location, time, etc) and learn how these features relate to spam. They learn a classifier and use that to predict if a new email is spam or not. From my understanding, companies have focused on simpler algorithms, e.g. heuristic and signature approaches, because the ML approach requires both good features as well as LOTS of data. If you host emails all day, that's not such a big problem. But for viruses, it wasn't really clear either what the features should be or how to get enough viruses/clean files to learn a model with.\n\nI know of at least one company, [Cylance](_URL_0_), which is using this approach. I believe they just signed a big deal with Dell. With advances in neural networks (deep learning in particular), you can ignore the feature problem by just passing the files' compiled code to the model. Doing that means the individual features are quite dumb, which makes the learning problem harder. Apparently, they've found ways of amassing billions of malicious and non-malicious files to train with. Right now, this approach takes a lot of research and expertise to make work. Eventually I imagine it will become cheap and easy enough that it will replace other general-purpose consumer virus detection. ",
"Anecdote: I was trying to create a loop in one of my basic computer science classes for some test and my anti-virus kept deleting it. I was pissed until I realized it was deleting it because I had a glaring infinite loop written in the code.\n\nThat analysis saved my grade on that assignment."
]
}
|
[] |
[] |
[
[],
[],
[
"HTTP://Cylance.com"
],
[]
] |
|
kilm6
|
- the east vs west hip-hop feud
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/kilm6/eli5_the_east_vs_west_hiphop_feud/
|
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],
"text": [
"This began a while ago, in the early 1990's.\n\nPretend there was a large african desert. In the desert, there are many different animals, but the strongest, and most powerful ones, were the Lions. The desert was kind of split into two, so you had the \"Right side\" and the \"left side\" . Each \"side\" had one very large, powerful lion. Every animal on each side respected both lions. But after a while, the animals on the right side decided that they liked the RIGHT lion the best, and started to say mean things about the left lion. The people on the left did the same thing, they really looked up to their lion, and thought he was better than the lion on the right, so they said mean things about the lion on the right. Eventually the two sides really started to hate eachother, and even though both the lion's knew it was wrong to hate your neighbours . they refused to just lay down and sort the stuff out. Then, one day, the lion from the right side was over in the left side of the desert, doing a dance for all the animals to see. When he was done the show, a big mean poacher came and shot him with a bow and aarow, and then the RIght side lion died. Soon after, the lion on the left was killed too.\n\nIn adult terms:\n\nThe \"lion\" on the right is \"The Notorious B.I.G.\" , AKA \"Biggie\" , a famous hip hop artist from New york. The lion on the left was \" Tupac Shakur\" , an artist from California.\n\nIn the beginning of their careers, Biggie and Tupac were friends. They did shows together, recorded music together, toured together. They worked together, and did amazing things. Then, one night, Tupac was coming over to Biggies house, and when he was in the lobby of the building, some men jumped him and he got hurt badly, and hospitalized. He blamed it on Biggie, and said it was a set up. Biggie denyed the claims, saying he had noithing to do with it. Her tried to visit Pac in the hospital, but the hospital staff would not let him in. When all the hip hop fans from California gor word of this, they all automatically started a feud, hating the east coast , and eventually, these feelings were mutual.Tupac was later on killed. Then, a while later, after doing a show in California, biggie was killed by armed gunmen while driving back to his hotel from the show. The shooter was never discovered.",
"Tupac and Biggie used to be friends. Tupac got shot, and thought it was Biggie partially because of his song \"Who Shot Ya?\" Tupac made the song \"Hit em Up.\" Thus the feud.",
"This began a while ago, in the early 1990's.\n\nPretend there was a large african desert. In the desert, there are many different animals, but the strongest, and most powerful ones, were the Lions. The desert was kind of split into two, so you had the \"Right side\" and the \"left side\" . Each \"side\" had one very large, powerful lion. Every animal on each side respected both lions. But after a while, the animals on the right side decided that they liked the RIGHT lion the best, and started to say mean things about the left lion. The people on the left did the same thing, they really looked up to their lion, and thought he was better than the lion on the right, so they said mean things about the lion on the right. Eventually the two sides really started to hate eachother, and even though both the lion's knew it was wrong to hate your neighbours . they refused to just lay down and sort the stuff out. Then, one day, the lion from the right side was over in the left side of the desert, doing a dance for all the animals to see. When he was done the show, a big mean poacher came and shot him with a bow and aarow, and then the RIght side lion died. Soon after, the lion on the left was killed too.\n\nIn adult terms:\n\nThe \"lion\" on the right is \"The Notorious B.I.G.\" , AKA \"Biggie\" , a famous hip hop artist from New york. The lion on the left was \" Tupac Shakur\" , an artist from California.\n\nIn the beginning of their careers, Biggie and Tupac were friends. They did shows together, recorded music together, toured together. They worked together, and did amazing things. Then, one night, Tupac was coming over to Biggies house, and when he was in the lobby of the building, some men jumped him and he got hurt badly, and hospitalized. He blamed it on Biggie, and said it was a set up. Biggie denyed the claims, saying he had noithing to do with it. Her tried to visit Pac in the hospital, but the hospital staff would not let him in. When all the hip hop fans from California gor word of this, they all automatically started a feud, hating the east coast , and eventually, these feelings were mutual.Tupac was later on killed. Then, a while later, after doing a show in California, biggie was killed by armed gunmen while driving back to his hotel from the show. The shooter was never discovered.",
"Tupac and Biggie used to be friends. Tupac got shot, and thought it was Biggie partially because of his song \"Who Shot Ya?\" Tupac made the song \"Hit em Up.\" Thus the feud."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
2ie51w
|
why do languages vary so widely? is any proven correlation between language and the geography of the native speaker?
|
Why do we have such vastly alternative languages? Does the geography of one's birthplace have any part in the shaping of that person's language?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2ie51w/eli5_why_do_languages_vary_so_widely_is_any/
|
{
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"text": [
"Languages can be made in many, many ways and so people more or less in isolation make really different ones.\n\nOnes that grew around many others tend to make a family where there are far more similarities. The Spanish can more or less understand the Portuguese and vice-versa for example. \n\nThe geography isn't inherently related, but it does matter because obviously you'll speak what your parents spoke. ",
"Because languages naturally change over time, and when groups of people are separated from each other, their languages diverge.\n\nSo, for example, English immigrants went to what is now the USA speaking the same English as people in England. But over time the English spoken in England and that spoken in the USA diverged, so that now American English and British English accents are noticeably different. That change took 300 or 400 years.\n\nNow think of how much change could take place over much greater lengths of time- 800 years, 1000 years, 5000, 10,000, 60,000, 100,000 years. In pre-modern times long-distance travel and communication was much more difficult than it is today. People in distant parts of the world had no contact with each other and their languages grew apart for thousands of years. That's why there are so many different languages in the world today.",
"People who live in the same area will have related languages due to havening a common linguistic ancestry and influencing each other culturally and socially.\n\nExample: \"lift\" vs \"elevator\", \"lorry\" vs \"truck\", etc."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
|
1yzqxb
|
why am i able to remember words to a song i haven't heard in 5 years but i can't remember the name of the person i just met 5 minutes ago?
|
I asked this because the other day a song came on the radio that I haven't heard for years, and I was singing along to the lyrics as if I had just heard it. Then I met someone new, got their name and as they walked away I forgot got it. So I wondered........
As always,
Thanks for your time
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1yzqxb/eli5_why_am_i_able_to_remember_words_to_a_song_i/
|
{
"a_id": [
"cfp6rgi"
],
"score": [
3
],
"text": [
"Repetition is the key here.\n\nWhen you repeat a task or something (such as hearing words to a song you like) over and over again the information gathered tends to move from the short-term memory into the long-term memory, therefore making it stick in your head.\n\nHope this helps."
]
}
|
[] |
[] |
[
[]
] |
|
5q13pm
|
With MRI Magnets being ridiculously strong, Why don't they affect compasses, systems, animals, etc ?
|
I have heard that MRI magnets are something like 60,000 x stronger than the earth's magnetic field. If this is true, with thousands of them in operation world wide. Why aren't compasses, animals who navigate by the earth's north pole, instruments, and even the earth's magnetic poles affected by them ?
|
askscience
|
https://www.reddit.com/r/askscience/comments/5q13pm/with_mri_magnets_being_ridiculously_strong_why/
|
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"text": [
"A colleague recently re-purposed an old medical MRI magnet for use in a detector system. The stray fields from the magnet are a big concern, with modern magnets taking great care to have both shielding and compensation coils so that outside the magnet no strong residual fields exist. The regulations pertaining to such magnets are strict. They still carry warning labels, but the stray fields are much reduced. You also get a rapid decrease of the stray fields with distance from the magnet. \n\nAll of this reduces the effect of MRI magnets on wildlife, compass needles, CRT screens (no longer used), credit card magnetic strips in my pocket (definitely worth protecting) etc.\n\nYou will find [this](_URL_0_) interesting reading, with a list of references to further safety related documents.\n\n",
"Mainly size. The Earth's magnetic field has is poles at opposite ends of the planet so the field covers the entire world. But with a magnet such as one from an MRI the polls are very close together and so the field is pretty tight, and doesn't really extend far beyond the actual magnet. ",
"Here's a graphic that can help illustrate why that happens:\n_URL_0_\nThe number of lines in an area represents how strong the magnetic field is. Magnetic fields must always form a loop. Imagine completing those loops in your head. Even if you have 60,000 lines in the center of the magnet, as you walk further and further away, the lines rapidly become more and more spread out, until they are spread out much more than the earth's magnetic field lines and you no longer notice it.\n\nGreebo mentions shielding: This website has some nice graphics showing how shielding materials force the lines to return to the loop without spreading out into free space.\n_URL_1_\n\nWe have a magnetic that is more than 60,000 stronger than earth's field in our physics laboratory. The field is much less than the earth's field by the time you are in the next room.",
"Magnetic field strength diminishes with distance roughly according to the \"Inverse-Cube.\" that is.\n\nField strength ≈ max field strength / (distance)^3\n\nSo, if the field inside the machine is 2 tesla, then 4 meters away from it, the field will be only about 1/64th as strong, or about 30 milli-tesla. This is much less than the strength of a plastic refrigerator magnet.\n\nThe magnet inside and MRI is basically a cylindrical coil of a superconducting material, most commonly a Niobium-Titanium alloy. When cooled to a few degrees kelvin, this allows much higher currents than could be safely applied to traditional conductors like copper. The super high current allows very strong magnetic fields to be produced. \n\nAs you can see from [this computer simulation](_URL_1_), the field inside the coil can be quite high, but outside the coil, it is about 10-20 times weaker. The field strength quickly drops off with distance, becoming almost zero at about a distance of 10 times the coil's diameter. \n\nFurthermore, most MRI machines are surrounded by magnetic shielding materials such as [mu-metal](_URL_0_) which further work to contain the field, reducing the external field strength. In addition, rooms containing MRI machines are are usually surrounded by steel cladding to magnetically isolate the machine. \n\n\n"
]
}
|
[] |
[] |
[
[
"http://psqh.com/sepoct06/mrisuites.html"
],
[],
[
"http://figures.boundless-cdn.com/17206/raw/vfpt-solenoid-correct2.svg",
"https://www.kjmagnetics.com/blog.asp?p=shielding-materials"
],
[
"https://en.wikipedia.org/wiki/Mu-metal",
"http://www.quickfield.com/advanced/coil_b_magnetic_field.gif"
]
] |
|
21bojk
|
Does air resistance become harder to overcome the faster something goes?
|
Say a person riding a bike uses 80% of the input energy to overcome air resistance. Now the person speeds up. What happens to the percentage?
|
askscience
|
http://www.reddit.com/r/askscience/comments/21bojk/does_air_resistance_become_harder_to_overcome_the/
|
{
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"cgbk8a0",
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],
"score": [
5,
7
],
"text": [
"Yes, the concept involved is known as [parasitic drag](_URL_0_). It means that the energy required to maintain speed against resistance from the air increases at a higher rate than the speed. A rough example as clarification, actual ratios made up: It requires X amount of energy to maintain a speed of Y against air resistance. To maintain a speed of 2Y, it would take 4X amount of energy. ",
"At subsonic speeds, aerodynamic drag is directly proportional to velocity squared. Thus doubling your speed means you quadruple your drag.\n\n"
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Parasitic_drag"
],
[]
] |
|
2j3umo
|
how is it possible in the usa for (former) lobbyists to be elected into chairmen positions of federal commissions, when there is an obvious conflict of interest?
|
Hello as you may know, the Chairman of the Federal Communications Commission is Tom Wheeler, a former lobbyist for the cable and wireless industry. Furthermore the Chairman for Finance Commission of Texas is William J. White, a former executive of Cash America which is Payday-Loan company. Since I’ve heard of their election into those positions, I’ve been wondering how it is possible or even legal for them to hold such offices, albeit the potential business threatening legislations these Commissions are able to give?
Thank you
Links:
[Tom Wheeler](_URL_0_)
[William J. White](_URL_1_)
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2j3umo/eli5_how_is_it_possible_in_the_usa_for_former/
|
{
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"text": [
"Big money runs the US government, so this kind of corruption is expected, and basically *intentional*.",
" > Since I’ve heard of their election into those positions\n\nThat's because they were both appointed. \n\nAs for 'conflict of interest', that generally only refers to those relationships in which the person involved would gain direct financial benefit. In White's case, he was undoubtedly required to divest interest in Cash America when he became chairman. \n\nIn both cases, however, it's not really surprising that the chair of the FCC has experience in the cable and wireless industry, or that the chair of a finance commission has experience in the lending industry. The president is going to nominate someone with experience in that industry to lead the oversight of that industry. You wouldn't expect him to appoint someone who knew **nothing** about finance or communications, would you?"
]
}
|
[] |
[
"http://en.wikipedia.org/wiki/Tom_Wheeler",
"http://www.fc.texas.gov/memberbios/NEWWhiteBio.html"
] |
[
[],
[]
] |
|
env2cb
|
what’s a “war crime”? i hear people throw this word around so much it’s confusing.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/env2cb/eli5_whats_a_war_crime_i_hear_people_throw_this/
|
{
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"text": [
"Basically there are things a country is not allowed to do during a war, like to fire against medical assistance or to civilians.",
"Years and years ago, All the leaders of the country got together and said \"we are civilized people, not cavemen. If war were to break out, we should make a set of rules so that we stay civilized despite us trying to kill each other.\"\n\nThus we got what is called \"rules of war\" or \"international humanitarian law\"\n\nFor example, targeting civilians intentionally instead of the armed enemy. Torturing of any kind ( to include rape or sexual violence). Using a weapon outlawed by said rules such as napalm. A chemical substance that sticks to the skin and burns relentlessly that has driven people mad even after being saved and treated because the pain was too much.",
"Many, many countries signed international agreements that define what is legal and what is not legal during a time of war. For instance, executing a prisoner of war who was not resisting or threatening his captor would be highly illegal. Targeting civilian buildings where a lot of civilians are is also illegal (like hospitals or schools). Killing civilians in general? Illegal. Wearing an enemy uniform or the symbols of an organization like the Red Cross, which is supposed to be a neutral symbol? Illegal. Attacking the Red Cross? Illegal.\n\nIt's pretty straightforward honestly. If you're attacking someone who's given up or who never even participated in the battle, you're probably doing something illegal.",
"We've been fighting wars for a long time. In that time, countries have agreed that, even in a war, some things are Not Okay. Think of things like attacking medics, mistreating captives, using certain weapons like poisonous gases or white phosphorus that were invented, used and found to be too horrible. Deliberately targetting non-military stuff like hospitals or sites of historical importance. Deliberately going for noncombatants. You get the idea\n\nLaws were written up and treaties signed to make these rules official. \n\nIf you break them somehow, that's a war crime. You can be put in front of the International Criminal Court and tried like you would for any other crime.",
"There are various rules supposedly to keep war from getting totally out of hand, these include killing prisoners, targeting hospitals or civilians and other similar actions.",
"There's these international laws called the Geneva Conventions enacted after WWII in response to the atrocities committed by the Nazis. There's many kinds of war crimes, but the most common ones are the destruction of buildings and killing of citizens not involved in the war effort. The use of chemical and biological weapons, the killing of unarmed men, and so on.",
"It is the insane concept that we can have \"rules of war\" and that killing people in the wrong way is bad, but killing people by the rules is perfectly fine.",
"Many good points here about certain conventions that detail what is considered a crime. To add to them, keep in mind the the concept of irredeemable actions in war has been around for some time. Not attacking a ship with a white flag, killing the emissaries of an enemy etc. Basically it's an understanding the war comes to an end, and we still need to live in a world after it. It's a way for the worst of us to think they're not that bad, and a way for the best of us to move on after.",
"To ELI5: You know how somehow you play-wrestle with your friends, or play a game of [British bulldog](_URL_0_) and it's okay to be rough with each other? war crimes are like if one person kept biting or poking other people in the eye to win - nobody wants to play with them and they might get a Stacks-On.",
"Generally, things that cause excessive human suffering, and are not more effective than their alternatives, get banned.\n\nViolating those bans is a war crime.\n\nTorture, including rape. \nTriangular and serrated bayonets. \nPoison gas. \nLandmines. \nNot Taking care of the wounded in combat.\n\nThose things are all war crimes because they cause excessive human suffering that is not acceptable in \"civilized warfare\" between professional armies.",
"Soldiers are one of the most honorable professionals in the world. Even in war there is code. There is an order. Ethics to be held to. Sometimes in the frenzy of a long drawn war or due to lack of discipline or some misguided ideals some soldiers give them up. The rules of engagement is never meant to be taken lightly. But sometimes the decisions are tougher than it may seem. It's a crime when you break laws in civilian life. The same applies in military as well. Except some times only one side gets blamed for atrocities during war. And they get prosecuted for it too. Not too surprising since only the losing side takes the blame. As for some examples of war crimes check out the war crimes of the Nazis, Japs, Pakistanis, Nuremberg tribunals etc.\n\nCheers and Peace"
]
}
|
[] |
[] |
[
[],
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[],
[],
[],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/British_Bulldog_(game)"
],
[],
[]
] |
||
81ug6t
|
Is there any evidence that prehistoric peoples had language?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/81ug6t/is_there_any_evidence_that_prehistoric_peoples/
|
{
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],
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"text": [
"Yes. Prehistoric just means before written records. We know for a fact that language existed before written records did because we've been able to reconstruct things like Old Chinese and Proto-Indo-European. It wasn't until later when PIE split into the many child languages like Ancient Greek and Sanskrit etc that written records were coming into use.\n\nThrough the work that goes into reconstruction we can show demonstrable relationship between related languages and point to some earlier form of that language, the proto-language. This is much of what historical linguists are looking at, these kinds of correspondences that can show relatedness.\n\nNow, we can't put times on a lot of these things. We can't say exactly when, if ever, the reconstructed form of PIE was spoken. It's possible it was never spoken that way at a single time, that the reconstruction actual represents a range of times. Language doesn't change at a steady measurable rate through which we can make predictions going back in time. But it at least shows with clarity that it did exist in some relateable form, and this form predates written records, i.e. is pre-historic.\n\nWhat we can't do is say things like if Neanderthal's had language, or what it would look like. We can speculate based on brain size and what we know of anatomy, but just having the potential for language isn't the same as having language. We are still not in agreement as to where certain language families like IE first originated either. But we can say PIE existed, and at least have a rough estimate at who was speaking it. The same can't be said about Neanderthals because we don't have a bunch of extant child languages upon which to base out analysis.\n\nSo yes, there's not only evidence but certainty that prehistoric peoples had language."
]
}
|
[] |
[] |
[
[]
] |
||
7rcvl6
|
if the world is round and rotates, how do we appear to be standing upright at all times?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7rcvl6/eli5_if_the_world_is_round_and_rotates_how_do_we/
|
{
"a_id": [
"dsvx4qh"
],
"score": [
3
],
"text": [
"Because gravity pulls us toward the center of the planet. Just like if you take a plunger and stick it on a beach ball, it doesn't matter the orientation of the ball, the stick of the plunger sticks away from the center."
]
}
|
[] |
[] |
[
[]
] |
||
f3o98v
|
when we bend our elbows/knees why don’t our blood vessels flowing, like a hose?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/f3o98v/eli5_when_we_bend_our_elbowsknees_why_dont_our/
|
{
"a_id": [
"fhk0znq"
],
"score": [
7
],
"text": [
"Our arms an legs bend, not fold. When a hose folds it cuts the liquid supply, when it bends the flow is uninterrupted.\n\nThere is too much going on in the limbs with bone, muscle, adamantium, cartilage, etc, to fold."
]
}
|
[] |
[] |
[
[]
] |
|
f8ko2k
|
superdelegates...
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/f8ko2k/eli5_superdelegates/
|
{
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"text": [
"In American politics, a superdelegate is an unpledged delegate to the Democratic National Convention who is seated automatically and chooses for themselves for whom they vote.\n\nBasically, if you’re an important person (Governor/mayor/etc) in the party, you get to have your vote counted independently from the elected ones.",
"Keep in mind that the population as a whole doesn't really vote for the DNC representative directly. Much like the electoral college as the real last step for voting for president, the real candidate selection process involves \"delegates\" who attend the big event where the party selects its nomination. Those delegates are supposed to be representing the will of the people who voted for them to attend.\n\nSuperdelegates are delegates who didn't need to be voted in. They get to vote for the presidential candidate at the big event for free.",
"Are you referring to the superdelegates in the context of the Democratic Party primary process? This is probably better asked in r/AskAnAmerican, but I can give you a quick answer here. The Democratic nominee for president is selected at the Democratic Nation Convention in late summer. They are selected by having the majority of delegates at the convention vote for them. There are 2 types of delegates: pledged delegates and superdelegates. Pledged delegates are the ones the candidate wins in state primaries. For example, if candidate X wins 40% of the vote in a state which awards 100 delegates, candidate X would have 40 pledged delegates who vote for them at the convention (the math isn't that straightforward, it's just an example). Those delegates have to vote for that candidate on the first ballot. Superdelegates are not bound to any candidate. They can vote for whoever they want. Superdelegates are made up of Democrats elected to office (so members of congress, governors...etc) and party officials.",
"In the Democratic Party Primary that is run by the DNC, there are two types of delegates: delegates and superdelegates. There are 4750 delegates total and 775 superdelegates within that group, or roughly 16%.\n\nDelegates are assigned to the nominees based on number of votes by state. So if there are 10 delegates in a state, candidate A gets 60% of the vote, candidate B gets 39% and candidate C gets 1%, A gets 6, B gets 4, and C gets 0 as a non-viable candidate. Those delegates have to vote for their assigned candidate in the first vote at the convention, and they will since they’re generally supporters of the person they were elected for. After that, delegates that support candidates that have no chance of winning can vote for one of the likely winners. This gets weirder if there’s a caucus, but that’s a different topic.\n\nSuperdelegates are major party officials who get a say due to their power within the Democratic Party. Some examples would be Barack Obama, Bill Clinton, Chuck Schumer, Tom Perez etc. The DNC figures that while most should be chosen by the people, the people who have devoted their lives to the party and have succeeded in gaining support of the majority of the party deserve a special vote. \n\nLower level superdelegates typically vote for the nominee who won their state, but in some situations they’ll vote another way. They have never overturned an election, but technically they could, leading to the obvious criticism that Democrats should be voted for democratically, and not by party leaders. The converse argument is that if the people elect a non-democrat to be the party nominee by a small margin, they party (which is a private organization, not a real election) has the right to overturn someone that doesn’t really represent the party. \n\nFull disclosure: Neither of those are my opinion, just stating the common argument."
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
||
80duyl
|
what properties do cooking oils contain that make them beneficial for cooking?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/80duyl/eli5_what_properties_do_cooking_oils_contain_that/
|
{
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"text": [
"They should be cheap to produce in large quantities.\n\nThey need to withstand high temperatures without burning (despite what some other user said).\n\nThey must be non-toxic, not including any carcinogenic compounds they form when they're used.",
"To answer this in general terms, oil is used in cooking because it helps increase the rate of heat transfer, makes things less likely to stick to the cooking vessel, and can add extra flavors to the finished products.\n\nNow, when it comes to cooking a specific dish, there are certain things to look at when trying to pick the right oil to use. \n\nWhat kind of temperature are you going to be cooking at? Different types of oil have different smoke points, so you want to use something appropriate. If you're just sweating some veggies, then extra virgin olive oil is fine to use. If you're searing something on high heat, you will want to use something like peanut or avocado oil. \n\nAnother big concern when picking your oil is flavor. Some cooking fats bring a lot of flavor, while others are much more mild. I know I learned that lesson when I subbed evoo for vegetable oil when making brownies one time. Other things like butter or lard are also used for flavor, but could easily be out of place in the wrong dish. \n"
]
}
|
[] |
[] |
[
[],
[]
] |
||
289mn3
|
Was there any form of public transport in the Roman Empire similar to what we find today in that it had standardised routes and fees?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/289mn3/was_there_any_form_of_public_transport_in_the/
|
{
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"text": [
"I have removed all of the comments below, including a lot of discussion about the History Channel. Please remember the Rules for Ask Historians before posting.\n\nThere is no need to \"fill the void\", if you don't really know the answer and are not ready to back it up. Someone knowledgeable will come along in a little while.\nIt's also [explicitly mentioned in our rules](_URL_0_) lack of previous answers isn't an excuse to not follow the standards. Either someone knowledgeable will answer the question or they won't, your posting a partial answer is unlikely to change that and yes we'd *much* rather have questions stay unanswered rather than be answered with incomplete or misleading information. ",
"The closest thing would be the postal system or *cursus publicus* which had frequent stops where imperial officials could change their horses so that they always had a fresh mount. However, this was hardly public despite the name. You needed a diploma from the emperor himself to use it, but those were given out to all sorts of imperial officers, tax collectors, military officers and powerful families as an honor. The [Wikipedia article](_URL_0_) for this is actually pretty rigorous and includes primary references (the warning at the top is mostly because the author relied on personal research instead of quoting from secondary sources).\n\nAs for regular transportation, it was usually wrapped up in either trade or war. You could travel by booking passage on a ship bound for your destination (there probably weren't any passenger ships *per se*) or join a group traveling by foot out of your city. For example, when the wealthy virgin Melania decided to visit the monks in Egypt and Jerusalem she took a ship from Rome with a whole posse. When she traveled between Jerusalem and Constantinople, her posse hit the road and made the trip in record time probably by using the imperial post (she had connections to the imperial household). \n\nWhat about the people who couldn't afford to pay a posse or hire a ship? There is not much evidence for how these people traveled, but analogy to later periods can help. In early modern England, people met at taverns near the town limits to gather into a group for travel. Basically you would have the tavern for people going north, a tavern for people going south, etc. I imagine that people in ancient Rome did something similar. They met at a common location that was known as a place where you can join a group for traveling and departed together as a means of protection.",
"I've studied ancient Rome for a while and can't think of anything that *completely* fits the bill. Nor would I really expect one. Peasants would probably rarely go far from their home towns, Rome was walkable, and the people who really need to get places would either be taken there by the state if they were soldiers, or would be rich enough to afford travel by horse, cart or sea privately.\n\nA few things do come back to memory though.\n\nThe Romans *did* have a system of horse relays (i.e. swap your tired horse at a special horse swapping station for a fresh one; a really good ancient system of travel) called the *cursus publicus* but it was for agents of state really, carrying military or state messages to where they need to go. So that doesn't qualify, quite. Anyway, if you're interested in it Suetonius says:\n\n > To enable what was going on in each of the provinces to be reported and known more speedily and promptly, he at first stationed young men at short intervals along the military roads, and afterwards post-chaises. The latter has seemed the more convenient arrangement, since the same men who bring the dispatches from any place can, if occasion demands, be questioned as well. (Suetonius, *Aug.* 49.3)\n\nPerhaps slightly better for your purposes is the fact that the Edict of Diocletian's edict on maximum prices included some bits about travel. \n\nThis edict was enacted by Diocletian in 301 AD in an attempt to halt the rampant inflation that was happening at the time (through debased coinage I think). It set the maximum prices people could charge you for things Now, I don't know if you know anything about economics but this is always a terrible idea - forcing people to ask for less money than their goods and services are now worth. It was mostly ignored.\n\nBut it *did* set the maximum price for both sea and land (oxen-drawn) freight, so that probably constitutes 'standardised fees' at least. [source.](_URL_0_)\n\nSorry I couldn't help more. It's a great question!\n\nEDIT: Typos. Also I forgot to mention the name of the horse post system."
]
}
|
[] |
[] |
[
[
"http://www.reddit.com/r/AskHistorians/wiki/rules#wiki_no_partial_answers_or_.22placeholders.22"
],
[
"http://en.wikipedia.org/wiki/Cursus_publicus"
],
[
"https://www.princeton.edu/~pswpc/pdfs/scheidel/041307.pdf"
]
] |
||
2vsisq
|
Why are ice cubes white towards the centre but transparent towards the edges?
|
I've just finished a long work week, got home, and made a gin and tonic, and I'm looking at the ice cubes bobbing in it and noticed something I'd not paid attention to before: the cubes seem to be opaque in their core but more-transparent towards their crust. You can see what I mean in [this photo](_URL_1_).
Now other photos, like [this one](_URL_0_), show that the effect isn't universal (and I'm pretty sure I've seen perfectly clear ice cubes before, too). So... why are mine opaque?
If it helps:
* Mine were made in a conventional food freezer at -20°C
* I'm in a hard water area
* I'm using an ice cube tray which makes "cubes" that are actually trapezoidal prisms
Thanks!
|
askscience
|
http://www.reddit.com/r/askscience/comments/2vsisq/why_are_ice_cubes_white_towards_the_centre_but/
|
{
"a_id": [
"col1sik",
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],
"score": [
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6
],
"text": [
"Check [this](_URL_0_) out: \"Regular ice comes out opaque when gasses dissolved in the water get trapped and forced into tiny bubbles, or when ice freezes in a way that doesn't allow large crystals to form\". Boiling the water before freezing it helps reduce the opacity, and the shape should have little to no effect.",
"The water freezes from the outside edges towards the centre. At the start, there is still enough liquid water present to keep the dissolved gasses in solution so the ice at the edges is clear. At a certain point though, there is no longer enough water to hold the dissolved gasses and since it is now surrounded by ice, the gasses coming out of solution form bubbles in the ice as it continues to form. It is these bubbles that make the ice at the centre of the cube white."
]
}
|
[] |
[
"http://youthopia.in/you/wp-content/uploads/2015/01/three-ice-cubes.jpg",
"https://d2x3wmakafwqf5.cloudfront.net/wordpress/wp-content/blogs.dir/62/files/2014/06/ice-cubes.jpg"
] |
[
[
"http://www.wikihow.com/Make-Clear-Ice"
],
[]
] |
|
jooea
|
the mathematics behind the vanishing point (as best as you can)
|
So this answer could be answered by some math gurus, architects, or maybe some artists hopefully!
What is the mathematics to understanding the vanishing point and perspective? I understand that the vanishing point is the point in which the objects in your prespective get so small that they're too tiny to see but how does the math of this work, and how could there BE math to this? I believe this page explains it but I am not a clever enough ~~man~~ five year old boy.
_URL_0_
Thank you!
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/jooea/eli5_the_mathematics_behind_the_vanishing_point/
|
{
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"text": [
"Objects are typically located in three dimensional space, but when they are displayed, like in a computer game, in two dimensions, you need to do a projection. This is like taking a picture, it takes a three dimensional object and spits out a two dimensional image.\n\nThis image is dependent on where you are located when you take the picture, and where you aim your camera. When a computer tries to figure out what the picture will look like in a game, it can be complex, especially if it also needs to figure out things like lighting and shadows.\n\nWhere math comes in is that these projections are actually examples of something called a *linear transformation*, which is the basic object of study in the field of math called *linear algebra*. This field gives us a lot of tools to study linear transformations, and thus projections. It turns out the locations in 3D can be thought of as a series of numbers called a *vector*, and then a projection can be written as a *matrix* a rectangular array of numbers. You can then perform various operations on vectors using matrices.\n\nPerforming linear algebraic operations is one of the most basic functions of a computer, they need to be able to compute these objects very fast in order to play fancy computer games.",
"Objects are typically located in three dimensional space, but when they are displayed, like in a computer game, in two dimensions, you need to do a projection. This is like taking a picture, it takes a three dimensional object and spits out a two dimensional image.\n\nThis image is dependent on where you are located when you take the picture, and where you aim your camera. When a computer tries to figure out what the picture will look like in a game, it can be complex, especially if it also needs to figure out things like lighting and shadows.\n\nWhere math comes in is that these projections are actually examples of something called a *linear transformation*, which is the basic object of study in the field of math called *linear algebra*. This field gives us a lot of tools to study linear transformations, and thus projections. It turns out the locations in 3D can be thought of as a series of numbers called a *vector*, and then a projection can be written as a *matrix* a rectangular array of numbers. You can then perform various operations on vectors using matrices.\n\nPerforming linear algebraic operations is one of the most basic functions of a computer, they need to be able to compute these objects very fast in order to play fancy computer games."
]
}
|
[] |
[
"http://www.math.utah.edu/~treiberg/Perspect/Perspect.htm"
] |
[
[],
[]
] |
|
bfg6ex
|
how do whales regulate their temperature in the vastly different seas they travel?
|
For example, Blue Whales live everywhere from the tropics to the poles. How do they not overheat or freeze? Are they able to regulate the amount of blubber they have in these different areas?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/bfg6ex/eli5_how_do_whales_regulate_their_temperature_in/
|
{
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"eldjtsi"
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"text": [
"The blood going to vessels in the skin (outside the blubber) is shut off to raise body temperature in the cold, and increased to cool off in the tropics."
]
}
|
[] |
[] |
[
[]
] |
|
9fgszh
|
if everything in universe is made of lots different chemical elements, then how on earth exist things like human cell, flesh, neurotransmitter, heart, nucleus, etc?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9fgszh/eli5_if_everything_in_universe_is_made_of_lots/
|
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" > like, does dna have structure like say N5H3O8, something like that\n\nOf course. After all, DNA stands for deoxyribonucleic acid. [The wikipedia page has good images for the chemicals making it up.](_URL_0_)\n\nThe key is that chemistry is a bit more complex than it would seem at first. Its not as rigid as x chemical is made of y elements. It goes far more complex, for example, DNA is a molecule called a polymer, which is a long chain of smaller identical or similar chemical segments. Each segment in DNA is called a nucleotide, which encodes some kind of information. As it turns out, chemistry is a bit more mushy and not rigid like you probably learned in chemistry class.\n\nDNA is a chemical but much else of what you listed are bigger structures than just chemicals. The nucleus consists of many chemicals including DNA, other proteins, water, fat molecules, ect. The mitochondria as well consists of many chemicals as well.\n\n > isn't it impossible? how on earth can something exist out of rules of chemistry?\n\nWhy not? The rules of chemistry are sufficiently complicated to allow for complicated beings like us. \n\nEverything in the body consists of parts, which consists of other parts, which once again consist of other parts, until you get down to parts small enough we call molecules. ",
"Dna is just a combination of chemicals. DNA is short for Desoxyribonucleinic acid. DNA is just a combination of 4 different \"strands\" of chemicals combined into a double helix form which are repeated millions of times in a random order. The order is which these 4 chemical compounds are placed is what we call the dna sequence.\nKind of like how we place words in order to form a book, the order of these compounds are placed into certain orders to form \"information\".\n\nBut coming back to your original question: yes we are basically all just a bunch of compounds who through sheer luck got into the correct order to form life. Once 1 cell is formed, the hardest part is over, this cell can copy itself into 2 cells and keep splicing to form more. From here on out Evolution takes over.",
"Atoms and molecules are very small. The other things are much bigger, even though they are small. ",
" > Why they don't tell us cell is made of different elements, thus different chemicals? \n\nThe short answer is that it doesn't matter.\n\nIf you were to learn how to paint. You need to learn how to mix colors. But knowing exactly what the paints are made of has no bearing on the subject of painting. Similarly, what you studied is basic biology which aims to teach how things work on a cellular level. Whatever nucleus, dna etc. are made of has no impact on what they're trying to teach. ",
"You need [this](_URL_0_)\n\nThe human body is made up of:\n\n- Water 65% (by weight)\n- Protein 20%\n- Fats 12%\n- Other 3% (things like Hydroxylapatite, Carbohydrates such as glycogen and glucose, DNA, RNA, Dissolved inorganic ions such as sodium, potassium, chloride, bicarbonate, phosphate, gases such as oxygen, carbon dioxide, nitrogen oxide, hydrogen, carbon monoxide, acetaldehyde, formaldehyde, methanethiol, Ethane and pentane, oxygen free radicals, amino acids, fatty acids, nucleobases, nucleosides, nucleotides, vitamins, cofactors and Free radicals such as superoxide, hydroxyl, and hydroperoxyl)\n\nYou can look up each thing to see its chemical formula. But the most common ones:\n\n- Water is H2O\n- Proteins are very complicated incredibly densely folded long chain molecules made up primarily of Carbon, Hydrogen, Amino groups (NH2) and Carboxyl groups (COOH)\n- fats are hydrocarbons (long chains of hydrogen and carbon) ending in a carboxyl group (COOH). Quite a lot of our fat is triglyceride which is a compound of glycerol (C3H8O3) with three fatty acids (unsaturated: CH3(CH2)XCOOH where X is anything between 6 and 24, saturated has a few carbon double bonds in it and so is almost the same but minus a few of the hydrogens)\n- most of our other molecules are also carbon based but we've got salts (NaCl etc..) and all sorts in there too\n\nThe end result of all this is that a human is (by weight):\n\n- Oxygen 65%\n- Carbon - 18%\n- Hydrogen 10%\n- Nitrogen 3%\n- Calcium 1%\n- Phosphorus 1%\n- another 54 elements put together: 2%"
]
}
|
[] |
[] |
[
[
"https://en.wikipedia.org/wiki/DNA"
],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Composition_of_the_human_body"
]
] |
||
2cfvf4
|
how do celebrities get their "premium" usernames on social networks (like @justinbieber, etc...)? and if they pay for these usernames, how much? how does such a purchase usually pass off?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2cfvf4/eli5_how_do_celebrities_get_their_premium/
|
{
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"If the \"premium\" username is not available at time of account creation they usually have to contact whoever made that account name and ask them if they would sell it.\n\nIf it is an inactive or poorly managed account, sometimes they can ask Admins to close the account and give them the account name.",
"Awesome, something that I can answer! \n\nBackground about me: I currently have over 200 unique twitter usernames that I have 'saved' and occasionally sell to others. Lots of 3 character usernames, with a couple 1/2 letter ones as well. Work for a big brand that spends over 500k monthly on Twitter/FB.\n\nIf an account directly impersonates someone or infringes on a brand you can contact support and they will 'release' the username to the rightful owner. (i.e. If someone had the name @Audi and actually pretended to be Audi that gives them the right to claim the username.) \n\nIn terms of 'purchases' they can vary. I have sold a few verified accounts for $2k-$5k. Sold lots of unique handles for a $1k-$10k and 1/2 letters for 25k+. \n\nIf this sort of things interests you, do a quick google search of the twitter account @N and a crazy fiasco where the original owner was being blackmailed to give up access to the account.\n\nCheers!"
]
}
|
[] |
[] |
[
[],
[]
] |
||
fb256t
|
why does it matter that fat cells don't ever go away when losing weight?
|
Apparently fat cells can increase in size and the number of them can go up, but they don't ever go away, even when you lose weight. Why is this a big deal when it comes to losing weight? Sure, the cells may not go away, but don't they still get smaller?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/fb256t/eli5_why_does_it_matter_that_fat_cells_dont_ever/
|
{
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"The number of fat cells likely doesn't play a meaningful role in how easy or hard it is to get fat. Usually to add additional fat cells, one has to gain a lot of weight. \n\nThe type of people who become obese do so because they naturally want to and can eat a lot more than an average healthy person. They also do this while not being very active. If somebody loses weight quickly and doesn't maintain their healthy lifestyle, it will naturally be easy for them to get back to where they were. \n\nAnother factor is that if you lose a lot of fat and don't gain a lot of muscle, your caloric requirements will go down. If you go back to 4k calories a day you will gain weight faster.",
"Nutritionist here.\n\nThink of fat cells like empty water balloons kept in a bucket. If the water balloons are empty, they'll be able to get filled with water more quickly as compared to when they are partially or completely filled. Similarly, more the water in the bucket, more water can enter the balloon. Simple physics, right?\n\nApply this logic to fat cells. These cells never disappear or decrease in number. Their size is what changes during weight loss or gain. So, more fat gets available in the body, the faster these adipocytes get bigger in size.\n\nWhat matters is your energy output. If the output is greater than the input, meaning you're exercising and burning more calories than your consuming, you'll lose weight. If the output equals the input, weight remains constant. And if input is more than the output, you will put on weight by providing more fat to the adipocytes. Smaller the adipocytes, faster will their fat uptake happen."
]
}
|
[] |
[] |
[
[],
[]
] |
|
82cob0
|
why are many english words used in asian culture?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/82cob0/eli5why_are_many_english_words_used_in_asian/
|
{
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"text": [
"Speaking from the Chinese language, its because Chinese is a very old language, and new things are being invented in the West. So when something becomes new to them, and they learn the English name, most of the time they try and make it sound similar in their language."
]
}
|
[] |
[] |
[
[]
] |
||
3sscll
|
why are some atoms able to violate the octet rule in covalent bonding?
|
In the case of phosphorous, it can bond to 5 atoms and have the electron domains to handle it. Wouldn't the S and P orbitals be full? Where does it put the extra electrons?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3sscll/eli5_why_are_some_atoms_able_to_violate_the_octet/
|
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"text": [
"Elements in the third row and below have access to d orbitals in which they can place the extra electrons needed to form more than 4 bonds, breaking the octet rule. There are actually very few elements that obey the octet rule. As they say...rules are meant to be broken. It is still taught because it works for predicting the shape of covalently bonded molecules with smaller non metal atoms.",
"Umm, can someone ELI5 the question? I'm...dumbish.",
"Shouldn't this be something for /r/askscience?",
"Chemist here:\n\nAll answers referring to d orbitals are flat out wrong. The idea that an element can handle only as many bonds as it has valence orbitals is false. Multiple bonds can be made from a single orbital and many valence orbitals don't participate in bonding.\n\nThe main reason that elements below the second row can start to accomodate more bonds is that the orbitals start to get more diffuse and can participate in 3 center 4 electron bonds where you effectively create two \"half bonds\". \n\nI realize this isn't an ELI5 answer but I needed to put a stop to the misinformation. "
]
}
|
[] |
[] |
[
[],
[],
[],
[]
] |
|
15ppt5
|
How did the Japanese start the "kamikaze"/suicide ethos into its people?
|
I've been watching a lot on History/Smithsonian Channels lately on WW2 and I really want to do some more reading into the Pacific Theater during WW2. But what amazes me is the stories about Japan. Everyone learns about Europe and the Nazis, but I've since learned a lot more about Japan. The number of civilian deaths due to suicide are astounding. I've soldiers from Germany and most every other country surrender against almost impossible odds. But Japan seems to stand out in that being captured is the worst possible case. I've heard of thousands of Japanese civilians committing suicide, rather than being captured and everyone knows about the kamikazes. So what drove them to be so much more deadly, in the case of military strategy? How did this ethos get installed in both their soldiers and their people?
QUICK EDIT: I meant this to go to AskReddit, but I really want a good answer on this. And book recommendations b/c this is a fascinating topic.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/15ppt5/how_did_the_japanese_start_the_kamikazesuicide/
|
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"text": [
"Hi! I don't feel like I have the knowledge to answer your question appropriately, but since nobody else has responded yet, I hope you don't mind me linking to information from similar topics from awhile back.\n\nIf you read the comments [from this question](_URL_1_), it mentions a few important pieces to help answer your question:\n\n- American propaganda which led to Japanese soldiers believing they would be eradicated instead of captured alive.\n- the idea of suicide instead of capture isn't as unique to kamikaze as it seems. People can be convinced to fight to the death if they feel the cause is important enough.\n- The sense of honor or loyalty to the Emperor. This might also fall under propaganda. The government pushed revived Shinto beliefs onto the nation to increase national pride or loyalty. \n\n[This post](_URL_0_) has some good book recommendations about the people who became kamikaze pilots:\n\n- Kamikaze diaries : reflections of Japanese student soldiers by Emiko Ohnuki-Tierne\n- I Was a Kamikaze by Ryuji Nagatsuka\n\nThere's also some recent speculation that the idea of kamikaze pilots being so eager to end their lives for the sake of the nation is propaganda itself, and that the men/boys who volunteered were not as willing as we are led to believe.\n\nI hope someone with more knowledge than me can help round this out a bit better.",
"The word comes from the great typhoon of 1281. \nKamikaze or 神風 means *spirit wind*. The Kami were a variety of god-spirit that were associated with all sorts of natural and supernatural forces. The typhoons literally saved Japan from the second Mongol invasion, wiping out a huge mongol fleet. \nThe spirit wind was seen as a divine intervention on the side of the Kyushu japanese. We will never know if the mongols would have succeeded, or if they had, whether they could have held the big island for long. My feeling is yes to the former and no to the latter. \nI don't know much about the conversion of the term to suicide attacks.",
"In short, it was because of the extremely successful and pervasive effectiveness of the Japanese Imperial propaganda department. \n\nThey were very persuasive in convincing the Japanese civilians as well as Japanese soldiers that Allied troops were the scum of the Earth and the worst thing that could possibly happen to you and your family was fall into their hands alive. \n\n**They believed that capture would result in a fate worse than death.**\n\nFor a few things, they thought their women, even little girls, would be gang raped until they died or disposed of when they got bored. \n\nThey were told that their children would be tortured for sport and then would be eaten, dead or alive. \n\nThe disabled, elderly or otherwise infirm that could not be put to slave labor would be tied up and used for target or bayonet practice. \n\n**Imperial soldiers were taught to expect no mercy and to in turn give none.** \n\nThis became a sort of self fulfilling prophecy because the grim determination of the Japanese forces encouraged the Allied forces to be extremely liberal in their application of fire power and force. Taking Japanese soldiers alive as prisoners was a risk to their lives rather than a duty of war and soon many gave up trying. \n\nRumors of total annihilation and few to no survivors only fueled the beliefs of Allied and American cruelty. When Japanese soldiers heard of one garrison falling and none of the men making it out, they had no reason to believe that the same would not happen to them. \n\nCivilians were very much the same, and if anything the stories only grew more exaggerated and worse through rumor and hearsay because of the intense censorship meant very little actual news circulated. At least soldiers could know something through information circulating through the military channels. Civilians made due with what little scraps of information they had. \n\nBecause of the horrors of total war, especially once the fire bombings and saturation bombings of cities, factories, and ports began, **people in the homeland soon no longer had to talk in abstracts or point to numbers and reports.** \n\nThey could point down the street to where an entire family, women and children burn to cinders, their brains crushed to bits by falling debris. \n\nThey didn't have to talk about unnamed soldiers dying in a far away land. Here and now, their neighbors were maimed or worse. They feared for their friends, their children, their parents, for themselves. \n\nMany were wholly convinced that the Americans had come for total blood vengeance and would not rest until every last Japanese person was extinct. And it would not be a death that was easy in the coming. No, they believed it would be like hell on Earth until they were allowed to pass into a final peace from unbearable agony. \n\n**The soldiers were desperate in buying as much time for their family and fellow Japanese as possible**, either to secure a surrender or at least let their families and friends escape. They knew what the stakes were and were wholly committed to the cause. It was important for their families, but also for their greater family of the nation, of their fellow Japanese brothers and sisters, and of their Emperor, literal god father of the Japanese people. \n\nOf course serving their nation and the Emperor had something to do with it but it was not blind faith to some super Shinto state religion that drove them where most armies would have broken and scattered. And I doubt a great many truly wished to die. \n\n**It was simply that they saw no other alternative.** \n\nThey believed they were doing what had to be done. No more, no less. "
]
}
|
[] |
[] |
[
[
"http://www.reddit.com/r/AskHistorians/comments/w32fz/what_would_a_kamikaze_pilot_during_wwii/",
"http://www.reddit.com/r/AskHistorians/comments/13uqzh/concerning_kamikaze_attacks_what_fueled_them_and/"
],
[],
[]
] |
|
zyyv9
|
if israel just vanished overnight, would the tensions in the middle east get better? what would happen?
|
Not suggesting that it could, should or would, just interested theoretically in how the world might look if Israel had never existed.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/zyyv9/if_israel_just_vanished_overnight_would_the/
|
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"I'm willing to bet things would be worse world-wide is such an event happened. Mass panic would erupt since a nation, quite literally, disappeared and people would be wondering who would be next. Some would take it as a religious sign, signaling the apocalypse, no doubt leading to chaos and instability. ",
"It would still be the area which has holy sites for Christians, Muslims, and Jews. There would still be conflict. That's if you're talking about political borders. \n\nFrankly, the only thing that would relieve tensions in the Middle-East is if the people there didn't take religion so seriously. There are huge chasms between sects of religion let alone between separate religions.\n\nComing from an ex-Jew.",
"This is more of an opinion questions but I'll go with it:\n\nLet's say that Israel never became a nation in 1948. The Jewish people would most likely be killed off or immigrated somewhere else or go into hiding, pretty much what they did a few years prior during WW2. I don't think it would ease any tension because the new enemy would be anyone who was \"harboring\" the Jews."
]
}
|
[] |
[] |
[
[],
[],
[]
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|
9q1svx
|
what are the differences between the functions of a president, chairman, ceo, cfo, and coo in the corporate structure?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/9q1svx/eli5_what_are_the_differences_between_the/
|
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"It completely depends on the company. \n\nChairman typically refers to someone who represents the interests of the board/investors but doesn't oversee the day to day operation or manage the company.\n\nThe CEO is the head of the company and only answers to the board. Their chief role is to make decisions about long and short term strategy across the company. This is why they're paid so highly, they have the highest impact.\n\nCFO overseas the flow of money. Thing of it as accountant in chief. The actual role depends heavily on the business. \n\nCOO depends on the company and the person who fills the role. \n\nThere are other executives too, but it depends on the business and the industry. Every company is run differently, the titles don't mean a whole lot. You need to look at what individuals in the business actually do. ",
"CFO is the Chief Financial Officer, they oversee anything to do with the company's finance, accounting, and treasury departments. They're also responsible for reporting the company's financial progress to the board and shareholders.\n\nCOO is the Chief Operating Officer, they are responsible for the company's day-to-day operation. The specific departments and areas this covers will depend highly on the company. \n\nCCO or CMO - Chief Commercial Officer or Chief Marketing Officer, they are responsible for marketing, sales, and public relations. Not all companies have these.\n\nCIO - Chief Information Officer, they are responsible for IT, Information Systems, Network Engineering. As you can imagine, the importance of this role can vary greatly depending on the company (i.e., Applebees versus Google).\n\nCEO - Chief Executive Officer, the boss of all those guys I listed above. The CEO answers only to the board and the shareholders, and is responsible for implementing their vision for the company.\n\nChairman and President are a little more complicated, but it goes somewhat like this:\n\nLet's say you own 20% of a large retail chain. As a 20% shareholder for this fictitious company, let's say you get two board seats (and there are ten total). This is just to keep the example simple - but there can be any number of board seats representing any number of ownership interest - including none at all. You sit in one yourself, and put someone else you trust to always vote the same way you do in the second seat - but they may not have any ownership of the company like you. During a board meeting someone suggests the company expand to the midwest. You think that's a good idea, so you vote for it. Six out of ten vote yes, meaning the company will now begin expansion into the midwest. The Chairman of the board then goes to the CEO and says \"We've decided to expand to the midwest. Make it happen\". The CEO then becomes responsible for implementing this strategy in the most cost effective way. The CEO first goes to his COO and asks about adding more stores and a bigger operation. Then the CEO goes to the CFO to figure out how to pay for it. The CEO may also go to the CCO to look at marketing strategies, and then back to the CFO for how to pay for the marketing. After all this back and forth - the CEO selects the best ideas from the rest of his team, determines a direction and strategy, and then brings it to the board. You listen to his strategy, but note that dividends will be on hold for a couple years to help pay for the expansion. You don't like that, and neither does the rest of the board (because most are shareholders and earn money from these dividends). So you tell the CEO to try again, maybe suggest certain parts of the strategy that can be omitted to preserve dividends, and the process starts all over again. \n\nAlso keep in mind that when the CEO goes to the COO or CFO for information, they likely go to their Vice Presidents who then go to their Directors who then go to their Managers who then go to their Analysts or other staff. Then a series of analyses and information works its way back up the chain to the COO. This is why those positions require someone with so much experience and pay so much. You have to know a lot about how every single branch of the company works in order to get the right information.\n\nEdit: Made some changes based on u/DoctorOddFellow's points for better accuracy.",
"The main distinction to be aware of here is the difference between the board of directors and the company employees.\n\nThe board of directors are the people who own the company (because they own lots of shares in it), or people who are elected by the shareholders to sit on the board and represent the shareholders. They are the people who actually own the company, or represent the people who do. As such, their decisions are ultimately the ones that the company follows. For example, Arthur D. Levinson is the Chairman of the Board of Directors for Apple. He represents the interests of Apple's shareholders, and gives directions (hence \"director\") to the company to do stuff.\n\nThe CEO - Chief Executive Officer - is an employee of the company. They may look like they have a lot of power - and they do - but ultimately, they do what the board tells them to do. For example, Tim Cook is the CEO of Apple. His job is to run Apple. He doesn't own Apple (except that he owns 0.02% of the shares). He makes a lot of decisions about how Apple operates day to day, but ultimately, he does what Arthur D. Levinson tells him to do. If the Board decides that Apple is going to start selling electric guitars, then it's Tim Cook's job to build an electric guitar factory, even if he thinks that's dumb.\n\nThe other C\\*O positions are also employees who report to the CEO. They have people reporting to them, and so on down the line.\n\nNow, the names depend on what country you're in, and on the particular culture of the company in question. President is usually roughly equivalent to CEO, and some companies are run by a person titled \"President and Chief Executive Officer\".\n\nOh, and to make things more complicated, sometimes the CEO and the Chairman are the same person. Some people think that's a good thing, some people think that's a bad thing.",
"The CEO is like the captain of a ship. Their job is to manage the running of the ship and its crew, and to navigate the ship where it is supposed to go. \n\nThe Chairman is the head of the Board of Directors, who ultimately are responsible to the shareholders. These people are like the owners of a ship. They are not directly involved in the running of the ship, but as people who have invested their money, they want to know that their ship is in good hands. They don't want a captain who will drive the ship onto the rocks or blunder into a war zone.....\n\nSometimes the ship owners know alot about ships and shipping, and may have even done sailing of their own in the past. So they will have very firm ideas on how they want their ships to be run and where they want them to go, and the captain's job will be to put their wishes into practise. Other times, the ship owners mightn't know much about shipping at all, it's a purely financial investment. So the captain might have a lot of freedom to use their own initiative in running and navigating the ship. \n\nIf it is a big ship, then the captain cannot possibly be expected to manage everything by themselves. So they have senior officers in charge of individual parts of the ship; engine room, deck crew, gunnery, navigation, administration, etc.... These people are in charge of their own departments, but need to report to the captain. The COO, CFO, and other 'C titles' are the equivalent of these senior officers (e.g the COO is like the First Officer who is more \"hands on\" in the day-to-day running of the ship, and the CFO is the Purser who is responsible for finance and administration). ",
"Besides the definitions that others said, the most important part here is that there is a difference between the people who run the company and the people who own the company. \n\nThe board of directors is the organ that represents the shareholders, the ones who own the company. Their main concern therefore is money. They decide on the purpose and vision of the company. The Chairman of the board leads these discussions. \n\nThe CEO, as the name says, is in charge of execution. He is the one in charge of actually running the business, and accomplishing the vision of the board. Therefore he usually also has a seat in the board. \n\nAll other C*O functions are the chiefs of a specific department: finance (CFO), IT (CIO), Technology (CTO), ... and they report to the CEO. \n\nIn new companies, the founders usually occupy many of these positions. They have a majority share in the board, and in case of a Zuckerberg/Musk they remain CEO for a long time. In the long term the visionair CEOs views usually don't align with the board's anymore, and they may be asked to step down. Over time CEOs usually become CEOs accross multiple companies, sometimes in very different branches. ",
"The management of most corporations starts with a Board of Directors. \n\nThe **Board of Directors** represent the interest of the shareholders and investors. In public companies, **Directors** are elected to the Board by the shareholders. In private companies, the Directors may be appointed by the owners/investors. \n\nThe **Chairman** is the person who presides over the Board of Directors. He or she is typically elected by the other members of the Board, although, again, may be appointed in a privately-held company. \n\nThere are technically two types of Chairman: a **Non-Executive Chairman** and an **Executive Chairman**. A Non-Executive Chairman *only* presides over the Board. An Executive Chairman *both* presides over the Board of Directors *and* has an operational role in the company. The Non-Executive Chairman sort is overwhelmingly more common, however you frequently see the Executive Chairman role in start-ups where the founder holds both the Chairman & CEO title or where you have two co-founders -- one might be CEO and the other might be Executive Chairman. \n\nBoards might also elect a **Vice-Chairman** and it's technically possible to be a **Co-Chairman**, i.e. two people sharing the role (although that's fairly rare). \n\nThe purpose of the Board of Directors is to represent the interest of the shareholders by hiring (or firing) the CEO, guiding the overall strategy of the corporation, approving the annual budgets, etc. \n\nThe **Chief Executive Officer (CEO)** is the highest ranking executive in the company. He or she is hired by and reports to the Board of Directors. The CEO is responsible for all aspects of the corporation, and all the other executives report to the CEO. \n\nThe **Chief Financial Officer (CFO)** reports to the CEO and is responsible for the financial operations of the company, including budgeting, financing, accounting, etc. \n\nPretty much only the CEO and CFO are required positions that *every* company has.\n\nThere can be many other **C-level executives** (sometimes also called **C-Suite executives**), depending on the company. Some common ones are:\n\n* A **Chief Operating Officer (COO)** reports to the CEO and is responsible for the day-to-day operations of the company. \n\n* A **Chief Information Officer (CIO)** reports to the CEO and is responsible for the information, network, and data systems of the company. These are usually *internal* facing information, network, and data systems to distinguish them from a CTO (see below).\n\n* A **Chief Technology Officer (CTO)** reports to the CEO and is responsible for the creation and management of technology products the company sells or offers. These are usually *external* facing technologies. I.e. while the CIO might maintain the company's HR system (which it buys from some other company), the CTO is responsible for building the software product that the company sells. \n\n* A **Chief Marketing Officer (CMO)** reports to the CEO and is responsible for marketing across all the company's brands and products. \n\n* A **Chief Revenue Officer (CRO)** reports to the CEO and is responsible for driving revenue for the company, i.e. for sales. \n\n* A **Chief Legal Officer (CLO)** reporst to the CEO and is responsible for all the companies lawyers and legal activity. Frequently paired with the title \"General Counsel.\" \n\nAnd so on and so forth. Besides the CEO and CFO, there's really no limit on the types of C-suite level offices that a company can create. What they all have in common is that they report directly to the CEO of the company. \n\nA **President** is an optional role in most companies' organizational structure. Many times you will see the CEO have this title as well, i.e. \"CEO & President, John Doe.\" \n\nIt's possible, and not uncommon, for a company to have a separate CEO and President. In those cases, the President almost always reports to the CEO and takes over some of the responsibilities that would otherwise normally fall on the CEO. \n\nSome times a corporation may have multiple divisions within the company and *each* will have a President that leads it. For example, a single, large multi-national company could still have a single CEO, but *also* have a President of North America, a President of Asia-Pacific, a President of Europe, etc. In this sort of structure, the Presidents are responsible for the company operations in their region. It doesn't have to be organized regionally, though. For example, a big media company might have a President of Broadcast Programming, a President of Film Production, a President of Interactive Media, etc. It's just another organizational layer. \n\nBelow the C-suite officers and/or President(s), the next layer down is usually one or more layers of **Vice-Presidents**. Depending on the company size there may be multiple layers of Vice-Presidents. When there are multiple layers of VPs they are usually labeled (in descending order) Executive Vice-President, Senior Vice-President, Managing Vice-President, and Vice-President as necessary ... although that layering and naming will vary widely from company to company\n\nBelow Vice-Presidents, you frequently have **Senior Directors** and **Directors** ... though not to be confused with the Directors who sit on the Board of Directors!!! \n\nNote: all of the above is from the perspective of US corporations. Outside of the US, terminology and corporate structure can be very different!\n\n\n\n\n",
"One thing I'd add that most of the other answers didn't mention.\n\n**The CFO is more than just the accountant-in-chief.**\n\nHe or she is responsible for the company's interaction with capital markets. They are responsible for overseeing the operation when the company does an IPO, issues secondary stock offerings, issues bonds or takes on debt financing, performs share buybacks. They have to know the pros and cons of these approaches, which one is best given their company's situation, and be able to handle it smoothly.\n\nThis is why so many large-company CFOs formerly worked at investment banks. It isn't because Goldman Sachs has a top-notch CPA program."
]
}
|
[] |
[] |
[
[],
[],
[],
[],
[],
[],
[]
] |
||
3o3h46
|
why are pencils hexagonal while pencil crayons, pens, and mechanical pencils are round?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3o3h46/eli5_why_are_pencils_hexagonal_while_pencil/
|
{
"a_id": [
"cvtmtq7",
"cvtz7lf"
],
"score": [
8,
2
],
"text": [
"The way they are made. Crayons are basically extruded. They flood molds with colored wax and the crayons are cooled and solidified pushed out and wrapped. Mechanical pencils are melted plastic shoved into molds and then put together.\n\nPencils are made with two sandwiched, half pencil, pieces with lead between them. Then they are cut apart. If they were extruded, they would likely be round.\n\nHope this helps.",
"*First, it is cheaper to make pencils with six sides because more\npencils can be made from the same amount of wood. The wood that could make eight round pencils can be made into nine hexagonal ones.*\n\nSource: Some website.\n\nWith hex pencils, you can simply cut all the wood with a flat blade. Rounding takes a bit more work and has a bit more wasted wood.\n"
]
}
|
[] |
[] |
[
[],
[]
] |
||
1q9xnh
|
Books about Steppe Warriors
|
Good evening Historians, I believe someone here may be able to help me out. Can anyone recommend a book(s) about steppe warriors? Preferably one that is maybe just a broad overview through history. i.e.- covers Scythians, Huns, Turks, Mongols, etc, etc without being too specific to one particular group. Getting my feet wet in this realm of history and a point in the right direction would be much appreciated.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1q9xnh/books_about_steppe_warriors/
|
{
"a_id": [
"cdao2k6"
],
"score": [
6
],
"text": [
"I can't recommend the following books enough:\n\n* *Early Riders: The Beginnings of Mounted Warfare in Asia and Europe* by Robert Drews\n\n* *Nomads of the Eurasian Steppes in the Early Iron Age* by The Kazakh/American Research Project\n\n* *The Horse The Wheel and Language - How Bronze-Age Riders from the Eurasian Steppes Shaped the Modern World* by David W. Anthony\n\n* *Mongols, Turks, and Others - Eurasian Nomads and the Sedentary World* by Brill's Inner Asian Library\n\n* *Cumans and Tatars - Oriental Military in the Pre-Ottoman Balkans, 1185-1365* by Istvan Vasary\n\n* *Polovtsi* by Svetlana Pletnev\n\n* *The Bulgars and the Steppe Empire in the Early Middle Ages - The Problem of the Others* by Tsvetelin Stepanov\n\n* *The Empire of the Steppes - A History of Central Asia* by Rene Grousset\n\n* *The Other Europe in the Middle Ages - Avars, Bulgars, Khazars, and Cumans* by Florin Curta and Roman Kovalev\n\n* *The Seljuks* by V.M. Zaporozhets\n\n* *Warfare, State, and Society on the Black Sea Steppe, 1500-1700* by Brian L. Davies"
]
}
|
[] |
[] |
[
[]
] |
|
2865x3
|
the best soccer leagues, and players and what i should watch.
|
I'm an American (as you can tell by
My use of soccer) and I want to watch some European soccer but I have no idea where to start.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2865x3/eli5_the_best_soccer_leagues_and_players_and_what/
|
{
"a_id": [
"ci7ryr2",
"ci7xcxu"
],
"score": [
4,
3
],
"text": [
"Start watching the English Premier League...The season just ended a few weeks ago with a good finish. Manchester City won the season by only 2 points with Liverpool in 2nd place and Chelsea in 3rd. Its fast paced soccer that is the most popular league in the world. A lot of good players",
"Very difficult to generalize leagues as every team has their own style, but l'll try to loosely sum up the best 4 leagues: \n\nEnglish Premier League: the most well rounded league. This league seems generally more fast paced with a loose play style compared to the other big leagues. They're home to a lot of powerhouse and famous teams, including Manchester City, Manchester United, Chelsea, Liverpool and Arsenal. Some key players: Yaya Toure (Man City), Van Persie (Man U), Gerrard (Liverpool), and Suarez (Liverpool). \n\nLa Liga (Spain): Home of the two best soccer players in the world in Messi and C. Ronaldo, as well as two of the next upcoming phenoms in Neymar and Bale. Very tactical/organized soccer style in this league; minimal mistakes, patience for good opportunities, and beautiful passing. Not as well rounded as the EPL, but their big teams are loaded with the best and most expensive players in the world. Best teams: Atletico Madrid, Barcelona, Real Madrid. Key players: Christiano Ronaldo (Real Madrid), Gareth Bale (Real Madrid), Messi (Barcelona), Neymar (Barcelona), Diego Costa (Atletico Madrid).\n\nSerie A (Italy): Defense, defense, and some more defense (still fun to watch though). The Italian club teams aren't as strong as they used to be, but their best teams are still top notchl. Not the most well rounded league anymore. Key teams: Juventus, AC Milan, Inter Milan, AS Roma, Napoli. Key players: Pirlo (Juventus), Baleotelli (AC Milan), Chellini (Juventus), Totti (Roma), Higuain (Napoli). \n\nBundesliga (Germany): a little difficult to sum up their play style; a little mix of EPL and La Liga. The least well rounded out of the other 4 leagues, but still home to two of the strongest teams in the world. Key teams: Bayern Munich, Bayer Leverkusen, Borussia Dortmund. Key players: Ribery (Bayern), Robben (Bayern), Muller (Dortmund).\n\nNotable club teams not in these leagues: SL Benefica (Portugal), FC Porto (Portugal), Olympique Lyonnais (France), Paris Saint-Germain FC (France). \n\n\n"
]
}
|
[] |
[] |
[
[],
[]
] |
|
f9hnt
|
How/what does an electroencephalogram detect?
|
I work in a lab that uses an EEG to measure neural activity, but have little idea about what the 'raw signal' is and what I can then conclude from it. What I do understand is that firing of neurons or net synaptic activity contribute to volume conductance of ions to the scalp. These are my questions though:
1. In a 3-electrode EEG, what does each sensor do and how do they interact? Two clips go on the ears, for instance, and I'm not sure how that helps to measure neural activity.
2. The other electrode goes on the top of the head, which makes sense, but does it measure just the net electric potential at that point?
3. Is the source of the electric potential the axon firing or the excitatory/inhibitory post-synaptic potentials?
Thanks for any information you guys can supply!
|
askscience
|
http://www.reddit.com/r/askscience/comments/f9hnt/howwhat_does_an_electroencephalogram_detect/
|
{
"a_id": [
"c1eapar",
"c1eb1ri"
],
"score": [
11,
3
],
"text": [
"You are correct in assuming that the EEG is a result of EPSP/IPSP contribution from pyramidal cortical cells. This is due to collective current sinks/sources resulting from these synaptic activities. Here's a simple [illustration](_URL_0_) detailing the phenomenon. \n\nAs for the specifics of cranial electrode placements, it would be unwise for me to comment since I use intracranial implants. The reason being is that scalp EEG has rather poor spatial resolution. This is because the skull can pick up activity from around the brain- and EMG artifacts. Further, it doesn't allow for much information coming from activity below the cortical pyramidals. Of the information they do supply, you cannot adequately detect high-frequency oscillations because of an effect called \"spatial summation\".\n\n",
"I can't speak to knowing this with any certainty, but it seems to me that the electrodes clipping onto the ears might be there to establish a ground or reference baseline that the other electrodes are measured relative to."
]
}
|
[] |
[] |
[
[
"http://www.ccs.fau.edu/~bressler/EDU/CogNeuro/Images/EEG_Generation.JPG"
],
[]
] |
|
doyacq
|
how come cutscenes aren't preloaded in video games? like a 4k hd video?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/doyacq/eli5_how_come_cutscenes_arent_preloaded_in_video/
|
{
"a_id": [
"f5rcck7"
],
"score": [
6
],
"text": [
"It depends on how the cutscene is rendered (how it is drawn in the game).\n\nIf it's a scripted cutscene, then everything is being shown in the actual game itself, which means everything has to be loaded as if you were playing the game even though you probably can't control anything except for the camera if that.\n\nIf it's a \"computer-generated imagery\" (CGI) video, then it can load like a regular video file which cuts down on the amount of time needed to load and play it."
]
}
|
[] |
[] |
[
[]
] |
||
3298do
|
i don't really "feel" like a male. how come people experiencing gender dysphoria "feel" like the other gender?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/3298do/eli5_i_dont_really_feel_like_a_male_how_come/
|
{
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"cq920ux",
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"cq97bgr"
],
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5,
18,
2
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"text": [
"Look at yourself in the mirror. Look at your dick. Does that body part look and feel like something that is a part of you? Does it feel normal for it to be there? Because if you experience gender dysphoria you cannot answer yes to those questions. Your genitals will feel as wrong as having a second head on your chest. ",
"The way I try to imagine it is if I woke up tomorrow as a man (not my original gender). Nothing wrong with being a man so no offense, but I'd be horrified. This is not who I am. I'd spend every waking minute of my life from then on trying to change my body into a girl's, because that's what feels right. Of course this analogy has its limitations because transgender people don't just wake up one day as the opposite gender, but this is as close as I can get to imagining it. I definitely feel my femaleness after imagining that",
"What I wonder is when someone says they feel like the opposite gender, how do they know what the other gender feels like? You can feel as if you like things that you and others associate with the other gender, but if you are not able to do the Vulcan Mind Meld, you would not really know for sure."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
5ztinc
|
if earth had rings like saturn, how would that affect sending satellites into orbit?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5ztinc/eli5_if_earth_had_rings_like_saturn_how_would/
|
{
"a_id": [
"df1112e"
],
"score": [
5
],
"text": [
"Short answer: life would be very difficult trying to orbit satellites in the presence of rings.\n\nRings exist in circular orbits in a very flat plane exactly above the equator (the equatorial plane). Satellites would need to avoid passing through this plane at the same altitude as the rings or they're likely to hit a ring particle and be vaporised. While there are gaps in rings and they have a limited extent, the boundaries are not sharply defined; there's just a smaller but non-zero chance of encountering ring material away from the rings.\n\nEvery orbit is going to pass through the equatorial plane twice per orbit, except an exactly equatorial orbit which is on the plane all the time. The safest orbit for a satellite would be for it to pretend to be a ring particle and have a circular, equatorial orbit and be a part of the rings. Getting into that orbit in the first place would be tricky but not impossible. It might require a few risky plane crossings between launch and final orbit but the level of risk would depend on the exact nature of the rings.\n\nOur large, close moon means that we can't have rings like Saturn, or at least not for very long. The moon doesn't orbit exactly in the equatorial plane so its gravity is going to move the ring particles out of the plane and out of circular orbits so that they start to collide with each other. Any realistic ring scenario for earth is going to involve changes to the moon."
]
}
|
[] |
[] |
[
[]
] |
|
7bo2fh
|
if conjoined twins share a stomach, do they both feel full or hungry at the same time?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7bo2fh/eli5_if_conjoined_twins_share_a_stomach_do_they/
|
{
"a_id": [
"dpjhsg2"
],
"score": [
10
],
"text": [
"It's hard to make general statement about conjoined twins because literally every case is different, but the feeling of hunger is regulated by hormones, most importantly Leptin and Ghrelin, which circulate in the blood. So if the conjoined twins share their circulatory system (which they *have to* if they share a stomach), then these hormones will always affect them at the same time. However, there might still be a different reaction in the brain to the hormones."
]
}
|
[] |
[] |
[
[]
] |
||
20q2wz
|
if everyone says california is so expensive, how do people afford to live there?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/20q2wz/eli5_if_everyone_says_california_is_so_expensive/
|
{
"a_id": [
"cg5ntzz",
"cg5ouuz",
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6,
2,
2
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"text": [
"Some make so much money it doesn't matter -- if you make $200k/yr, it's not a big deal. \n\nOthers request and accept cost of living adjustments from their employers. -- in Kansas, a position might be worth $60k/yr. In SF, it might be $90k/yr\n\nOthers just live in small places, drive small cars, and enjoy the sun.",
"Relativity.\n\nIf you make $10 an hour, and it costs you $9 an hour to survive, it's the same as making $20 and costing $18 to survive.",
"Multiple income families. If your job isn't one that you get a real nice salary/decent salary from your employer who already adjusts the salary/wage to accommodate California standards of living. You live in the cheapest place you can afford, and you either drive if you can afford the insurance - can be triple if not more for insurance there than everywhere else - or you bus/bike/carpool/commute. \n\nNot married? It's not uncommon to find families still living in the same house no matter the size. I had not one single friend that didn't share a house/apartment with a sibling or their whole family. Because houses are //not// cheap. A friend bought a house just before I left, cost her just shy of 500k. I bought a house here where I live now, just less in size by about 200 square feet and it cost me a third of what she paid. \n\nYou adjust. Then you re-adjust. The demand to live there is great because you have temperate climes, there is a //lot// to do there. There's beaches, skiing, camping, shopping, see plays with the actors that you see on TV, bumming around small theatres and doing plays. \n\nIn my first week living there? I saw Jack Black filming a video. The opportunities there are //endless//. The //food//. Fruit is available all year round, not shipped in from far away destinations. Well, they still are in winter, but for about 7/8ths of the year, it's all california grown. Milk is cheaper there than here in Iowa which surprised us. Produce is cheaper there. Gas is more expensive but because of the strict demands for a better fuel and a special blend that California requires because the smog is //terrible// from all the cars. Car insurance is //three// times higher there, than where we are now because they accommodate for uninsured drivers and the sheer amount of other vehicles on the road. \n\nThe state itself is //broke// and desperate for money! Bleeding money. Expect to be audited every single year, as they scrounge for money. The tax rate the more money you make, is ridiculous. We got nailed //regularly// for about 35-30 percent taken off our bonuses and end of year and we were the middle to upper middle of \"middle class\" \n\nBut it's a great place to live. Ridiculous amount of stuff to do. You had the beach! Drive an hour away you have skiing! Want to see a limited engagement movie? You popped up to hollywood proper and you could see a sneak peek for free - yes, free - or a limited run - Hello Shame! I was friends with someone from the cast of Nurse Jackie, and learned of the The Blank Theatre who puts on the Young Playwrights Festival and you could go and see big name actors putting on the plays of teenage playwrights that were //really// good. Jerry O'Connell? He is //tall//. You had Knott's Berry, Disneyland, go another hour away to San Diego and you had Legoland. There's //always// something to do, and it's not all expensive to do. Well, Disney is expensive. It's 90 bucks a person no matter what. You find ways to live there. You either grew up there and your life adjusted, or you moved in and you have a job/s with an adjusted salary. \n\ntl:dr Multiple incomes, multiple individuals in an abode, employer adjusted salary. Take advantage of free stuff to do, enjoy the beach and fresh produce.\n\nI do miss the beach :( I loved the seals."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
7j6yyh
|
why does the visible light spectrum appear cyclic to the human eye if the spectrum is based on specific linear wavelengths of light?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7j6yyh/eli5_why_does_the_visible_light_spectrum_appear/
|
{
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"text": [
"It doesn't appear cyclic to the human eye. It appears cyclic to the human *brain*. \n\nOur eyes can detect 3 \"regions\" of color: red, green, and blue. If we detect some combinations of those, we typically perceive that as an \"in-between\" color. For example, orange light stimulates both the red and green sensing cells in our eyes. So stimulating the red and green cells is what we perceive as \"orange\". And, interestingly, if we just use red and green light (no orange light), we can stimulate those cells exactly the same as orange light, and so we still see orange. In fact, that's the basis for how computer and phone displays work: They only emit red, green, and blue light, and our brains perceive combinations of those as other colors.\n\nBut here comes the strangeness! What happens when you stimulate the red and blue cells in the eye with red and blue light? Well, your first guess is that we should perceive the color that is \"in between\" red and blue on the spectrum. But that color is green, and we're specifically *not* stimulating the green-detecting cells in our eyes. However, your brain isn't really capable of seeing it as two different colors (red and blue) simultaneously, so it invents a new color! Purple!\n\nThat's right, purple, the color that allows our sense of the spectrum to be cyclical, *isn't a real color*. There is no such thing as a purple photon of light. Purple can *only* be perceived by the human brain as a side effect of the limitations of our visual system.",
"Just to add something extra to the excellent explanation already provided...\n\nOur color vision is usually a matter of our vision system interpolating between the colors detected by our three flavours of cones in our retina. Think of it like a triangle, with red, green and blue in the corners and all the other colors somewhere in the middle.\n\nBut then consider that a small percentage of human females are \"tetrachromats\". For them, there are 4 types of color receptors in their retina. For them, the perceived color is interpolated between 4 different points. You have to imagine this in 3d now, like a 3 sided pyramid with 4 point of detected color, and some interpreted color point somewhere in the 3d space of the pyramid.\n\nTetrachromats may be able to distinguish 100 million colors ...\n\n_URL_0_\n",
"ELI5: what does OPs question mean?",
"Could you also explain the question like I'm 5?",
"Pink/ magenta bridges the gap between red and blue. Usually there would be no specific wavelength to represent pink, however our brains made up a colour to find the average wavelength of red and blue . It couldn't be green, since this new colour should be the opposite of green. There's a great explanation by minute physics on the topic.\n\n_URL_0_"
]
}
|
[] |
[] |
[
[],
[
"https://en.m.wikipedia.org/wiki/Tetrachromacy#Humans"
],
[],
[],
[
"https://youtu.be/S9dqJRyk0YM"
]
] |
||
4buf29
|
Do we have evidence to prove that the Pyramids in Bosnia were constructed 10,000 years ago to even 24,000 years ago?
|
[deleted]
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/4buf29/do_we_have_evidence_to_prove_that_the_pyramids_in/
|
{
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10
],
"text": [
"Hi, there are a few archaeologists here, but it might be worth x-posting to a sub with more eg /r/AskScience, /r/Archaeology or /r/AskAnthropology ",
"They *are* just ordinary mountains. A few cranks (most definitely not archaeologists) have been trying to convince people they're pyramids for years now, and unfortunately had some success within Bosnia, but there is zero support for the theory amongst actual archaeologists and never has been. There are no chambers or cut stones. The pyramidal shape is the result of a well known, natural geological process and there is no evidence of any sort that they have been artificially shaped. It's pure, unadulterated pseudoscience and unfortunately in their quest to \"prove\" their theory (by digging ridiculously deep holes every year and misinterpreting natural fissures in the bedrock as \"cut stone\") the pyramidists have damaged genuine archaeology on the mountains. So if your dad is interested in Bosnia's heritage you'd do well to warn him against supporting these people."
]
}
|
[] |
[] |
[
[],
[]
] |
|
6fx1g4
|
since a normal human can run 8-10 mph but top athletes can run over 20 mph, if a cheetah "trained", could it potentially sprint much faster?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/6fx1g4/eli5_since_a_normal_human_can_run_810_mph_but_top/
|
{
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"text": [
"Almost all cheetahs are clones of each other. Theoretically every cheetah is already a top athlete since they are all pretty much identical. \n\n[source](_URL_0_) ",
"not really... cheetahs are genetically born to run this fast. \ntheir whole life is already dedicated to running and they are born with the right genetics for speed , same as athletes. \n\nthere might be faster and slower cheetahs, but the variance is not as great as with humans, so you wont be able to train a cheetah to run 50% faster, maybe 10-20%",
"No. They're all constantly training to catch their food. The average human doesn't need to run 20mph to survive on a day to day basis, but you had better believe that if they did then all the humans on earth would be running like that. Cheetahs do need to run fast to live, so you won't find any cheetah that isn't in top shape.",
"I mean considering wild cheetahs run to eat and ensure survival, I'm pretty sure they are the equivalent of 'trained'. Maybe 9 to 5 office cheetahs who do paperwork for a living could improve speeds though."
]
}
|
[] |
[] |
[
[
"http://www.smithsonianmag.com/science-nature/rare-breed-20811232/"
],
[],
[],
[]
] |
||
a07mgz
|
why do you feel hot when you have a blanket on, cold when you take the blanket off but if you leave one leg out of the blanket, it’s perfect?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/a07mgz/eli5_why_do_you_feel_hot_when_you_have_a_blanket/
|
{
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"eaf7omg",
"eaf8mgo"
],
"score": [
10,
4
],
"text": [
"When the blanket is on there is too much insulation so your body warms up. With the blanket off there is too little. So you need something in between. Having a leg out allows heat to leave your body. Therefore, you’ve achieved that in between that you needed.",
"You suffer from hot leg syndrome.\n\nOne leg is very much hotter than the other and ambient cooling is a logical response.\n\nUnfortunately this condition is terminal, often in the timeframe of 40-60 years."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1yczgt
|
if source code is readable, and executable programs are not, what happens to cause that?
|
I don't understand the barrier between readable source code and executable/compiled programs. If the system knows what to do with the program (aka how to add/subract/ work with variables) why can't all code be decompiled?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1yczgt/if_source_code_is_readable_and_executable/
|
{
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"cfjdeat",
"cfjeqqn"
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"text": [
"what is lost is variable names, method names that make the program human readable. \n\nwhile you can probably figure out what mystring.left(5) does just by looking at it, you probably won't be able to tell what \"on the object at memory location 0x12343, invoke method in library 0x342424 at location 0x242425\" \n",
"If you know about programming you know about \"syntax\" and \"semantics\". The semantics of the your compiled program and source code are the same, but syntactically they are very different. \n\n1. Program 1: \"1+2+3+N=4\"\n2. Program 2: \"1+5+N=4\"\n3. Program 3: \"6+N=4\"\n\nIf I'm a smart compiler all of these are identical AND I don't need to keep track of the particular \"syntax\" that was utilized to write these three different programs. So...getting back from the compiler which of these three (and the infinite number of other) possible syntaxes that could have created the same logic is impossible.\n\nTake that example and extrapolate!\n"
]
}
|
[] |
[] |
[
[],
[]
] |
|
5h9kri
|
Prior to the US Civil War, was it common practice to euthanize slaves who were too old or sick to work?
|
I understand that older slaves were used in house labor and other tasks less physically demanding than the field labor. But once the person was too old to do even that, or perhaps contracted a communicable disease that could cause other slaves to die, was it common practice to "put the slave down" like we do with old house pets today? What about slaves born with birth defects or severe intellectual disabilities?
Not sure if this would have been documented, so it may not be answerable.
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5h9kri/prior_to_the_us_civil_war_was_it_common_practice/
|
{
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"daz0n4l",
"dazsfvy"
],
"score": [
3,
3
],
"text": [
"If I can expand - what about sterilizing slaves to control population? Or abortion?",
"I don't know about euthanizing slaves but it wasn't unheard of for older slaves to be manumitted (legally freed) so owners didn't have to continue their upkeep. States usually had laws on the books that required a freed slave be able to provide for themselves to hinder this practice, but by the mid 19th century manumission had become legally very difficult anyway. "
]
}
|
[] |
[] |
[
[],
[]
] |
|
nnpxd
|
Is there a psychological reason why people with NO attraction to their own family members, find incest so arousing?
|
I was reading this thread: [IAMA Man who had a sexual relationship with his mother. (Probably NSFW)](_URL_0_) and started becoming extremely aroused. I've noticed this in the past when reading about incest or viewing incest-related material. By material, I mean incest-themed anime or stories, not *actual* incest pornography.
Mentally, I know two things:
1. I have zero attraction to my own mother or any other family members. And, like any young man that's read Oedipus Rex, I've thought about the possibility of having an attraction.
2. Most incest is realistically sexual abuse rather than consensual sex. And, even if it resembled the latter, there would bound to be negative psychological effects for at least one of the participants.
So, is this all related to the Oedipus Complex? Why is there such a strong attraction to incest even though a lot of us do not have those urges (directed at our own family members), and know that incest is fundamentally wrong?
|
askscience
|
http://www.reddit.com/r/askscience/comments/nnpxd/is_there_a_psychological_reason_why_people_with/
|
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"FWIW, saying taboo words has been found to alleviate pain. _URL_0_ \n\nHumans often use the word \"naughty\" as a positive descriptor of sexuality. This suggests that perhaps it's the actual 'forbidden' quality of profanity or taboo sexuality that some people find positive. \n\nIt's a little speculative, but less speculative than the alternative explanation-- 'projected' sexual feelings towards your own family members that your 'conscious' mind rejects. \n\nLastly, to throw out a question-- perhaps there is some 'quality' to incest-themed pornography that is generally lacking in most porn. For example, maybe you like extremely \"loving and nurturing\" sexuality that theme is played up in the kind of work you enjoy? Or something like that-- some unique quality that appeals to you-- forbiddenness or something else. ",
"There is a psychological effect known as the Westermarck effect which basically prevents us from having sexual attraction to our siblings. We are conditioned throughout our lives to seek sexual partners outside our immediate kin groups. One of the ways this manifests is in the dampening down of feelings of attraction to our siblings and parents.\n\nAs to why we are aroused by incest? I can't say for certain, but one hypothesis regarding the formation of sexual attraction put forward by Daryl Bem suggests that exotic stimuli become erotic stimuli. At the level of the nervous system, arousal is arousal, no matter what the source. This effect has been demonstrated with crossover between fear and sexual excitation, as well as physiological exertion and sexual excitation. When something excites us because it is taboo, because it is strange and exotic, we can mistake this excitement for eroticism. If this sort of mistake happens at the right stage of psychological development, it can become fixed as a sexual proclivity.\n\nTL;DR: We have developed a mechanism to stop us having three-eyed babies, but weird shit still makes us hot.",
" > Why is there such a strong attraction to incest even though a lot of us do not have those urges (directed at our own family members), and know that incest is fundamentally wrong?\n\nHow is it wrong if you're not impregnating?",
"I suspect that the simplest answer as to why you find incest arousing would be that you've (presumably unintentionally) conditioned yourself to find it arousing. If the previous incest-themed material you viewed also included *sexual* themes, then you may have begun to associate incest with sexual arousal.\n\nThat's a pretty speculative answer, to be honest, because as far as I'm aware there hasn't been much experimental research done on sexual fetishism. ",
"I think it's more to do with how much people find the whole \"want something that you can't have\" story. For many people, incest seems to be a form of almost childhood friend type relationship, that person that you seemed to know forever. But it also has the taboo attached to it that says you cannot or should not have it. \n\nSo now you have a relationship between two people who know everything about each other and are as close as humanly possible being forced apart by social norms. The fact that they cross those boundaries and finally get what they both wanted seems to excite people, or at least fulfill fantasies of that one forbidden love they could never have (similar to how impossible it is for most people to have sex with famous celebrities they can't have)",
"There seems to be a relationship between arousal and taboo or shame or something of that nature, perhaps just novelty. I know that exchange relations have a lot to do with why incest is taboo in the first place, which is adaptive because it encourages a collection of new traits and ideas over generations. It could be that we're wired to find the exotic attractive, so an idea that's completely outside one's normal ideas about sexuality may be a turn-on where the manifestation of that idea would not be because you then would no longer be dealing with something exotic (the idea) but with something familiar (the individuals). ",
"Normally its the fact of \"forbidden love\" that arouses people",
"FWIW, saying taboo words has been found to alleviate pain. _URL_0_ \n\nHumans often use the word \"naughty\" as a positive descriptor of sexuality. This suggests that perhaps it's the actual 'forbidden' quality of profanity or taboo sexuality that some people find positive. \n\nIt's a little speculative, but less speculative than the alternative explanation-- 'projected' sexual feelings towards your own family members that your 'conscious' mind rejects. \n\nLastly, to throw out a question-- perhaps there is some 'quality' to incest-themed pornography that is generally lacking in most porn. For example, maybe you like extremely \"loving and nurturing\" sexuality that theme is played up in the kind of work you enjoy? Or something like that-- some unique quality that appeals to you-- forbiddenness or something else. ",
"There is a psychological effect known as the Westermarck effect which basically prevents us from having sexual attraction to our siblings. We are conditioned throughout our lives to seek sexual partners outside our immediate kin groups. One of the ways this manifests is in the dampening down of feelings of attraction to our siblings and parents.\n\nAs to why we are aroused by incest? I can't say for certain, but one hypothesis regarding the formation of sexual attraction put forward by Daryl Bem suggests that exotic stimuli become erotic stimuli. At the level of the nervous system, arousal is arousal, no matter what the source. This effect has been demonstrated with crossover between fear and sexual excitation, as well as physiological exertion and sexual excitation. When something excites us because it is taboo, because it is strange and exotic, we can mistake this excitement for eroticism. If this sort of mistake happens at the right stage of psychological development, it can become fixed as a sexual proclivity.\n\nTL;DR: We have developed a mechanism to stop us having three-eyed babies, but weird shit still makes us hot.",
" > Why is there such a strong attraction to incest even though a lot of us do not have those urges (directed at our own family members), and know that incest is fundamentally wrong?\n\nHow is it wrong if you're not impregnating?",
"I suspect that the simplest answer as to why you find incest arousing would be that you've (presumably unintentionally) conditioned yourself to find it arousing. If the previous incest-themed material you viewed also included *sexual* themes, then you may have begun to associate incest with sexual arousal.\n\nThat's a pretty speculative answer, to be honest, because as far as I'm aware there hasn't been much experimental research done on sexual fetishism. ",
"I think it's more to do with how much people find the whole \"want something that you can't have\" story. For many people, incest seems to be a form of almost childhood friend type relationship, that person that you seemed to know forever. But it also has the taboo attached to it that says you cannot or should not have it. \n\nSo now you have a relationship between two people who know everything about each other and are as close as humanly possible being forced apart by social norms. The fact that they cross those boundaries and finally get what they both wanted seems to excite people, or at least fulfill fantasies of that one forbidden love they could never have (similar to how impossible it is for most people to have sex with famous celebrities they can't have)",
"There seems to be a relationship between arousal and taboo or shame or something of that nature, perhaps just novelty. I know that exchange relations have a lot to do with why incest is taboo in the first place, which is adaptive because it encourages a collection of new traits and ideas over generations. It could be that we're wired to find the exotic attractive, so an idea that's completely outside one's normal ideas about sexuality may be a turn-on where the manifestation of that idea would not be because you then would no longer be dealing with something exotic (the idea) but with something familiar (the individuals). "
]
}
|
[] |
[
"http://www.reddit.com/r/IAmA/comments/nmmjr/iama_man_who_had_a_sexual_relationship_with_his/"
] |
[
[
"http://veggierevolution.blogspot.com/2009/09/swearing-relieves-pain-new-neurological.html"
],
[],
[],
[],
[],
[],
[],
[
"http://veggierevolution.blogspot.com/2009/09/swearing-relieves-pain-new-neurological.html"
],
[],
[],
[],
[],
[]
] |
|
czekbm
|
what happens to all the water after a hurricane/flood? does it just recede back into a body of water?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/czekbm/eli5_what_happens_to_all_the_water_after_a/
|
{
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"Not en expert but I know that some of the water gets infiltrated into the water table which can cause salt water intrusion which is bad",
"Basically, yes. A good portion is absorbed into the ground and into the ground water system. In the case of a flood, there's simply more water flowing into a body of water than is flowing out. Hurricanes are a bit different because their winds effectively make a massive ocean tide that can reach miles inland if the land is flat like Florida tends to be, or below sea level like in certain parts of Louisiana.",
"Civil engineering major here with background in water resources and hydrology. In urban and suburban areas, eventually the majority of the water will go into the wastewater system to either be reclaimed (cleaned for use) or the excess will be directed through the appropriate channels to points that can accommodate the influx. The remainder will seep into the ground or slowly evaporate, and some will follow naturally formed channels into tributaries and eventually rivers and other large bodies of water. In rural areas with less hydrologic infrastructure, natural channels will take away a good portion of the water, and the rest will seep into the ground (farmland has a higher water capacity than urban areas), although due to lack of proper drainage, some water will sit in large puddles until manually removed or until sufficient time has passed that it seeps down or flushes out."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
2ctk7p
|
Why does buoyant force only work for fluids?
|
If I put some packing peanuts in the bottom of a bucket of extremely finely ground sand what happens on the molecular level that keeps them from floating to the top as if I put them in a bucket of water?
|
askscience
|
http://www.reddit.com/r/askscience/comments/2ctk7p/why_does_buoyant_force_only_work_for_fluids/
|
{
"a_id": [
"cjiuyaa"
],
"score": [
16
],
"text": [
"There is no mechanism preventing it. In fact, if you gently shake the container, the larger pieces _will_ rise to the top. This is known as the [Brazil nut effect](_URL_0_).\n\nBuoyancy exists in fluids because they are free to flow and fill a container, which is what allows them to \"push out\" a buoyant object. Likewise, if you choose a very viscous fluid and submerge a buoyant object, it might take a while before it floats up."
]
}
|
[] |
[] |
[
[
"http://en.wikipedia.org/wiki/Brazil_nut_effect"
]
] |
|
19xrhw
|
How closely (i.e. distance from the surface) can something orbit the Earth?
|
So to put it plainly (as I understand it), how far above the surface of the planet would something have to be to achieve a stable orbit? Is there a minimum distance/altitude/mass/velocity required for a stable orbit? If so, why do they put communication satellites, probes, telescopes and space stations at the altitude they do when in orbit?
|
askscience
|
http://www.reddit.com/r/askscience/comments/19xrhw/how_closely_ie_distance_from_the_surface_can/
|
{
"a_id": [
"c8sbhpn"
],
"score": [
3
],
"text": [
"Below about 200 km (120 miles), orbits decay rapidly due to atmospheric friction. On the moon, where there is no atmosphere, there is really no minimum orbital altitude, though you couldn't really put something in orbit a foot off the ground since the ground isn't perfectly flat. Almost all satellites are in Low Earth Orbit, which starts at this minimum distance and extends to about 2000 km. There's no reason to spend extra fuel (and money) to put something in orbit farther away unless there's a good reason to do so."
]
}
|
[] |
[] |
[
[]
] |
|
2s5du3
|
Around 400 before christ, when Greece became a democracy. What was the tasks of the king?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2s5du3/around_400_before_christ_when_greece_became_a/
|
{
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"text": [
"I think you have the wrong view of how Greece worked in those days.\n\nGreece was divided into a multitude of city states, some of the allied in Legues, but not all. These city states were spread from the Crimea to Iberia, with Sicily and southern Italy (Magna Graecia, or larger Greece) as prominent places.\n\nSome of these city states were oligarchies, were a few powerful families ruled. Some were tyrannies (which simply meant a single ruler back then) and a scant few others were democracies. A few others were monarchies.\n\nThose that were democracies did not have a King and thus no tasks for him. Athens, the most prominent democracy, would probably be considered a failing democracy under today's standard - citizens could vote other citizens out of their citizenship and voting rights (which happened on a massive scale on at least one occasion).\n\nThe two Kings of Sparta were not Kings in the meaning we give the name now - they were more like military commanders, and they were appointed by the Spartan assembly, which included all Spartan citizens (who were a very small minority of Spartan society), so Sparta can probably be called more of an oligarchy than a monarchy or democracy.\n\nMacedon was a Monarchy, but was not a city state and was during the classical era considered only semi-Greek by the other Greeks.\n\nArgos, Thebes and Corinth all developed from oligachies into monarchies during the era though.\n\nBut to answer your question - there were no democracies in the Greek world that also had a monarch.",
"As /u/vonadler says, there was no unified \"Greece\" with a singular government, but there are still some common processes that the Greek city states went through in their political development. These often had different results in different areas, but they can often be seen as responses to a similar set of social circumstances.\n\nPinning down kingship in Greek history is somewhat complicated because by the time real written sources begin the institution had either disappeared or been completely changed throughout the Greek world. It left a powerful memory on Greek mythology and literature, but by the sixth and fifth century \"kings\" as such can only really be found on the margins, such as in Macedon or Epirus. To find it in the core areas of Greece requires leaping back to the Bronze Age, in which two relevant institutions appear in the Linear B tablets: the *wanax*, which most closely corresponds to a conception of \"king\" as found in the Near East, and a *basileus*, which seems to have been a sort of subordinate chief. The word *wanax* remained in the Greek language as an intentional archaism when referring to kingship, but the institution itself seems to have disappeared with the Mycenaean palace complex in the turmoil of the so-called \"bronze Age Collapse\"--or at the very least evidence for it disappears with the loss of the practice of Linear B writing and the disruption in the artefactual record. The term *basileus*, however, survived, and became the common word for king used in, for example, the Homeric epics. It is possible that the *basilei* were local leaders under the supra-regional *wanaces*, and with the destruction of the palace society they were able to solidify their autonomous authority, but this is speculative.\n\nThe problem with this theory is that we don't actually have direct evidence for the *basilei*. They dominate the landscape of Greek mythology, but we simply cannot take the dramatic scene of the *Antigone* or *Agamemnon* as an accurate depiction of the politics of an ancient Greek city, as that was neither within the intention or capability of the playwrights. Homer is sometimes taken as a source, but the society of Homer is deliberately archaic, he was not portraying the society of his own day but of a remote and idealized past. It is possible that the *basilei* held on for a few centuries after the destruction of Mycenaean palace society, leaving a heavy ideological footprint on the oligarchic societies that followed, but we simply don't know. Unlike the Romans, the Greeks did not really maintain much in the way of a concrete memory of a transition from a regal to non regal political order.\n\nThe society described in the early literary record can be broadly described as oligarchic, with elite families competing for influence among themselves. The social processes of the Archaic, particularly colonization, economic and demographic expansion, and the development of the classical polis society, had different results in different areas. In Athens, democratic forces \"won\", and a society emerged that carefully curtailed the competition of elites (for example, through the practice of ostracism, in which prominent citizens who got too big for their britches would be kicked out of the city for a decade). In Sparta, the oligarchic forces closed ranks, created a heavily regimented society carefully delineated along class boundaries. However, neither the basileus nor, and I find this crucial, the fear of a basileus survived. The Greeks expressed political angst through a fear of a *tyrannos*, which was monarchical but explicitly not *basilei*, as by definition they come to power through \"illegitimate\" means.\n\nIn short, in order to find \"kings\" as such one needs to go back to the Mycenaean period, and by the time the classical literary record kicks in they were long dissapeared and their memory filtered through many layers of literary artifice. Unlike the Romans who explicitly described a process of the loss of kingship, the Greeks (or at least the Athenians) did not retain a memory of throwing off the institution.\n\nI think this is given a very good description in Pomeroy's *Ancient Greece*."
]
}
|
[] |
[] |
[
[],
[]
] |
||
5ddqz3
|
what forces, on a molecular level, hold together a solid object and how are those affected when the object breaks in separate pieces?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5ddqz3/eli5_what_forces_on_a_molecular_level_hold/
|
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"It kind of depends on what sort of material you are talking about. I'll give you one example in (a bit of) detail, and then I will just name a couple of other forces that also could (not should per se) play a role. Here it goes:\n\nBasically every molecule has an interaction with it's neigboring molecule, that interaction is either attractive or repulsive. We call all these interactions Van der Waals (VDW) interactions/forces . Named after the Dutch scientist Van der Waals. We are only going to look at the attractive part of the VDW forces, since this is what you want to know. I always look at them as if they are the 'gravity' between two molecules. Meaning the VDW forces are stronger between two molecules that have a higher mass than between two with a lower mass. What happens when we break the material apart? When we break something we are pulling the two molecules far from eachother (we say: we broke the VDW bond), this cost energy (either heat, or mechanical like a scissor). \n\nNow, as I mentioned earlier there are possibilities to break other bonds as well, most notably the hydrogen bond. Here, like with the VDW force, we just move two molecules far from eachother and nothing really happens with the molecules themselves. One of the other things that could happen (in some cases, certainly not all) is we actually break a bond inside of a molecule (a covalent, or atomic bond). This will actually cause the molecule to break up in multiple pieces. There are some others and some technicalities that I'm not going to get into right now aswell. If you want to break something, what you are doing is breaking the weakest force available, whichever one that is. Most of the time it will be the VDW bond, but not necessarily.\n\nHope this helped!\n\n"
]
}
|
[] |
[] |
[
[]
] |
||
nepgx
|
Does the age at which someone begins puberty affect anything for the person's life later on down the line?
|
askscience
|
http://www.reddit.com/r/askscience/comments/nepgx/does_the_age_at_which_someone_begins_puberty/
|
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"This is just something I remember from a report I did on adolescent psychology but one of the most affected areas is self-esteem. Girls who hit puberty early are more likely to get male attention, negative and positive. It is usually from boys that are older than she is. The more negative attention, the lower the self-esteem. The attention that was seen as positive when she was younger can backfire and affect her negatively later in life, too. Boys who hit puberty late are often made fun of more by their classmates who may have hit puberty sooner. ",
"This is just something I remember from a report I did on adolescent psychology but one of the most affected areas is self-esteem. Girls who hit puberty early are more likely to get male attention, negative and positive. It is usually from boys that are older than she is. The more negative attention, the lower the self-esteem. The attention that was seen as positive when she was younger can backfire and affect her negatively later in life, too. Boys who hit puberty late are often made fun of more by their classmates who may have hit puberty sooner. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
28d19y
|
Why is the derivative of the volume of a sphere equal to its surface area?
|
I noticed that when you differentiate the equation for a volume of a sphere, you get the equation for it's surface area. Is this a coincidence? If not, would someone mind explaining the relationship?
V=(4/3)*pi*r^3
dV/dr=4*pi*r^2
dV/dr=Surface area
Please try to keep the answer *quite* simple if possible, I have not done maths at university or anything. :P
|
askscience
|
http://www.reddit.com/r/askscience/comments/28d19y/why_is_the_derivative_of_the_volume_of_a_sphere/
|
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"This is not a coincidence! Try deriving for yourself the volume of a sphere by integration. You can start with a surface of a sphere with zero radius, and integrate that out to the radius of your sphere. Think of that as having a a series of infinitesimally thin concentric shells from the center of the sphere out to the full radius of the sphere. That operation will \"sweep\" through all the volume of the sphere, accumulating the total volume of the sphere. That being an integration of the surface area through a radius, it's not a coincidence that a derivative of the volume of a sphere with respect to its radius is equal to the surface area.\n\n[Illustration.](_URL_0_)\n\n",
"Because integrals (the opposite of derivatives) are essentially infinite sums, and to get the volume of a sphere you can think of it by summing up each infinitesimal surface area from r=0 to r=R. The same relationship applies throughout geometry, for example the area of a circle (pi * r ^ 2) is the integral of the circumference (2 * pi * r).",
"Consider a sphere of radius r, where you want to increase the volume very slightly. You can do this by adding a layer of paint, covering the entire surface area, with a tiny thickness dr. The volume of paint you've added to the sphere is dV=(area)\\*dr.\n\nIntegrate both sides, which acts like adding infinitely many tiny layers. Start from radius 0 until you've built up a sphere of the desired size. The result is the volume formula, which you used as the starting point of your calculation.\n\nYou can do exactly the same thing for the area of a circle: consider a circle, of radius r and circumference 2pi\\*r. Paint such a thin circular ring, of thickness dr. Repeat this process (integration), until you've made a (filled) disk of the desired radius. The area will be the integral of 2pi\\*r: pi\\*r^(2).\n\n*Obligatory thanks-for-the-gold edit:* I'm glad that so many people have found my explanation useful. This gives me a bit of hope that I won't be a completely crappy teacher when I get that far in my career.",
"Suppose you painted your sphere. The amount of paint you need is equal to the surface area. But if you do this, the sphere gets a tiny bit bigger. Imagine the whole sphere is made of paint. Every time you paint it, you increase its volume by an amount equal to the area of the surface (the amount of paint) times the thickness of the paint (dr).\n\nedit: oops Overunderrated had already written a similar comment, which I didn't see. Glad to see it's now at the top ",
"The integral is always whats 'under' the 'curve'.\n\nWhat under the surface of a sphere, is the volume of the sphere.\n\nWhats under a line with a slope of 1, is the area of a triangle.\n\nWhats under the surface of a cube, the volume of a cube.\n",
"As it turns out, differentiating the volume of some 3 dimensional shape gives you the boundaries of that shape in 2 dimensions (ie- its surface area). This is true for surface area of a 2 dimensional shape (which is differentiated to 1 dimensions, a line) and a 1 dimensional line (which is differentiated to 0 dimensions, a point). Interestingly, this is also true for the volume of *4 dimensional objects*, which can be differentiated to 3 dimensional objects. \n\nThis means that 4 dimensional objects have 3 dimensional boundaries.\n\nEDIT: This is generally true only when 'volume' is understood as an integral equation describing area between boundaries of some n-dimensional shape. Differentiating that integral will, [according to the fundamental theorem of calculus](_URL_0_) return an equation describing the boundaries of that n-dimensional shape, which turns out to always be *n-1 dimensional* (though curved in n dimensions). Importantly, the result does not return an equation describing the surface area of the object (unless the object is a n-dimensional sphere or n-dimensional cube) but an equation describing the *surface* of the object.",
"The derivative is the rate at which something is changing.\n\nIf you took an existing sphere with a volume of V and you painted a new layer on it then the volume would grow by the volume of the layer of paint. As the thickness of the paint tends to 0 then you are looking at something more like the surface area of the sphere.\n\nThus you are changing the volume of the sphere at a rate equal to the surface area and the derivative reflects this.\n",
"derivative of **x** is the **change in x** right? So what happens when you get a very small change in the volume? So small that it was pretty much just a fraction of a layer on the sphere? You get the surface area (because the slice you added on was so thin).",
"This is a GREAT question, and the top answer by /u/listens_to_galaxies is very good. However, I'd like to make a PSA regarding the fact that many of the answers given here are overly simplified. (Yes, I know OP asked for a a simple answer.) They go vaguely like this: The region inside of a sphere is made of spheres of smaller radii, and therefore the volume must be the integral of the areas of those smaller spheres. The same reasoning is used in single-variable calculus classes when computing volumes of revolutions or volume by cross-section. (The resulting volume can be thought of as being made up of \"washers\" or \"cylindrical shells.\")\n\nBut this reasoning, *by itself*, is just wrong (as illustrated by /u/imtoooldforreddit 's example, which was only sort of explained away by /u/dpitch40). In order for the reasoning to be correct, we have to know that the variable we integrate over (which in this case is the radius r) has the property that its gradient is equal to the unit normal of the family of surfaces (which in this case is the family of spheres of different radii).\n\nIn the layman's terms used by /u/listens_to_galaxies, it means that the layer of paint that is added to the ball of radius r to obtain the ball of radius r+dr has uniform thickness dr. (This is why the trick doesn't immediately work for *diameter* a. The thickness of the paint to get from diameter a to diameter a+da in that case is only da/2.)\n\nThings get more complicated when the paint doesn't even have uniform thickness. Or more precisely, when the gradient of the variable you want to integrate over does not have constant length. When that happens, you get a more complicated formula known as the [coarea formula](_URL_0_). The reason why I bring this up is that is a VERY common mistake for students who are fairly well-versed in calculus to think that you can find the volume of a 3-dimensional region by just integrating the areas of a family of 2-dimensional surfaces that make up the 3-dimensional region, not realizing the importance of exactly how those 2-dimensional surfaces fit together. This is because in all of the examples that students see in calculus class, they happen to fit together nicely.\n\n",
"Here's a different take on the question. You can see why the formula (dV = S.A. dr) works for some cases and not others fairly easily. It's due to the formulas being expressed (or not) in the appropriate scale.\n\nFor instance this fails for the cube: V = s^3 and A = 6s^2. But dV = 3s^2 ds != A ds. Let's seek the scale that makes the formula work.\n\nLet s = m t and rewrite the equations to find the appropriate scaling factor m.\n\nV = (mt)^3 and A = 6(mt)^2. Then dV = 3 (mt) t^2 dt. Now we want to force the formula dV = A dt to hold. So set \n3m(mt)^2 = 6(mt)^2. Or m = 2. \n\nSo then rewriting the equations with the appropriate scale, we have:\n\nV = (2t)^3 = 8t^3 and A = 6(2t)^2 = 24t^2 which satisfy the relationship. Geometrically these correspond to thinking of t as a semi-side instead of a side. That is you place the center of the cube at the origin just like you do a sphere. \n\nYou can do this for general volume and area formulae (that is these formula work for cubes, spheres, whatever): V = k s^3 and A = c s^2. Then you find that the scaling factor is m = c/3k. Note that the 3 is this formula is related to the 3 dimension of space the sphere takes up. (You can do the same thing for area:perimeter formula and you'll get a \"2\" in the scaling factor) \n\nSo for instance with the sphere V = (4/3)pi r^3 and S = 4 pi r^2, you have m = 4 / (3 * 4/3) = 1. Which is to say that for that pair of formulae the scaling factor is *already* correct to get you the proper relationship. Or verifying the cube m = 6/3*1 = 2. \n\nYou can show with a bit more algebra that in general m = d V/A where m is the characteristic length , d is the dimension, and V/A is the volume to surface area.\n\nSome geometric intuition:\n\nWhen you write the differential of volume as dV = S.A. dr you're implicitly saying that you're \"painting\" (multiplying) the entire surface area with a coat of paint dr thick. If you're measuring your cube by its edge, (think of a cube in a corner) you're only painting 3 surfaces. If you put the origin in the center of the cube then you're painting all 6. This is where the 2x scale factor comes from. The analysis above basically tells you to find a scale factor that paints all 6 sides of the cube. \n\n\n",
"Simple answer, without going into the math so much:\n\nA derivative is a rate of change. When a sphere increases in size, what happens? It expands outward, adding more mass to the surface. When you roll a snowball to make it bigger, the snow packs on the surface, so the increase in volume is directly related to the surface area. ",
"To understand it qualitatively, reverse the question. \"Why is the integral of surface area volume?\" An integral is the summation of all iterations across a range, and is also an opposite of a derivative. If you add up the surface area of a sphere for every possible radius, you will have the full volume of that sphere of specified radius."
]
}
|
[] |
[] |
[
[
"http://rlv.zcache.com/the_formula_for_the_volume_of_a_sphere_post_card-rd4b30d5de3df49a7ba0f5c67058b71ac_vgbaq_8byvr_512.jpg"
],
[],
[],
[],
[],
[
"http://www.mathmistakes.info/facts/CalculusFacts/learn/doi/doi.html"
],
[],
[],
[
"http://en.wikipedia.org/wiki/Smooth_coarea_formula"
],
[],
[],
[]
] |
|
1tx8v1
|
why do i max out at around 3.2mbps wired and 2.5mbps wireless download speed when i pay for 30mbps?
|
Bonus Question: On a scale of 1-7 how much do you want to burn your cable company's headquarters to the ground?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1tx8v1/eli5_why_do_i_max_out_at_around_32mbps_wired_and/
|
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"text": [
"I'm pretty sure you know this already, but what they sell you is in mega bits per second, and when downloading it is displayed in mega bytes per second. \n\nEvery 8 bits is 1 byte, so a 30mbps connection is a 3.75 MB per second. \n\nIf you are downloading at 3.2 MB per second and not mbps like you say in the title then they aren't screwing you :) ",
"MB=/=Mb \n\nMegabits are used when it comes to Internet and connection stuff, Megabytes are for storage generally"
]
}
|
[] |
[] |
[
[],
[]
] |
|
2wp6sc
|
which is better for the environment on the small scale: using a plastic fork once to save water on cleaning silverware, or washing and reusing a stainless steel fork so a plastic fork won't end up in a landfill?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/2wp6sc/eli5_which_is_better_for_the_environment_on_the/
|
{
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"text": [
"Reusable cutlery is better for the environment. ",
"Considering the resources that go into extracting, refining, and machining the material in the steel fork, you'd have to use the SS fork hundreds if not thousands of times before you came out ahead from an energy expenditure standpoint.\n\nThere was a study done with ceramic vs. styrofoam coffee cups asking basically the same question. I'll try and find it.\n\nedit: [okay, so it wasn't a single study but it was an analysis that cited several studies](_URL_0_)."
]
}
|
[] |
[] |
[
[],
[
"http://www.slate.com/articles/health_and_science/the_green_lantern/2008/09/grande_americano_extra_green.html"
]
] |
||
5qr0sx
|
How Historically accurate is "Hellstorm-Death of Nazi Germany, 1944-1947" by Thomas Goodrich. It backs up all its claims with large amounts of detailed proofs, citations, sources on each and every page. However a lot of people call it Neo Nazi propoganda to gain sympathy for Nazi. What is the truth
|
[Link to the book in question] (_URL_0_)
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/5qr0sx/how_historically_accurate_is_hellstormdeath_of/
|
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"[This review](_URL_1_) should answer your question? Some of his sources are more than suspect, and it seems that where his facts are fine, his conclusions from them are not. [Ugh, it seems that he uses the IHR](_URL_0_) (Institute of Historical Review) and other hate groups for many of his sources. That alone should tell you this is not good history. If you are unaware, the IHR is one of the main Holocaust denial groups. Using Bacque and IHR? Just no.",
"Look through the neo nazi/holocaust denial mega-thead [here](_URL_0_). It won't answer your question directly, but give you the tools needed to make up an informed opinion on the book yourself. It's a great thread, worth every second of reading. I read it throughout the day a few months ago, and since, I've spotted so much holocaust denial (intended or not) that would just slip right beneath my eyes otherwise. ",
"It is a piece of Nazi propaganda, plain and simple.\n\nThe problems with this book start right in the text describing it: It talks about the millions who perished in the greatest mass migration known to men, meaning the flight and forcible expulsion of Germans from the Red army and from Eastern Europe, the \"post-war death camps\" and \"torture chambers\", and calls these all \"dark secrets\".\n\nFrom this short description alone, several things can be gleaned:\n\n* The book plays hard and lose with facts and interpretations: It mixes flight and forcible expulsion of German populations from Eastern Europe and claims it was \"the biggest mass migration known to man\", when in fact the extend of both phenomena, which are distinctly different (one being voluntary flight, one being forcible expulsion of a population by a state) affected the same number of people the Nazi forced labor program did, about 12 million people. Coupled with the German policy of ethnic expulsion and forcible resettlement in Eastern Europe, whose victims also number in the millions, this moniker Goodrich is trying to impose here shows in which direction he is heading with his book.\n\n* In the same vein and reinforcing this direction is the use of the term \"post-war death camp\". Nazi death camps such as Treblinka, Sobibor, Belzec, and Chelmno were camps designed to kill hundreds of thousands of people in little through gassings and shootings. In Treblinka alone 900.000 people were killed. Equating this with the – at times very unpleasant conditions – in Allied POW and war-criminal camps does not capture the historical reality of the latter (where due to initial problems with supplying food and water in April and May 1945 and the food shortage imposed supply of 1200 to 1500 calories per day – Nazi concentration camp prisoners receiving 700-900 calories per day – resulted in the death of 3000 to 5000 German POWs in 1945).\n\n* Calling the above \"dark secrets\" is like almost any book claiming to write the \"dark\" or \"secret\" history of something implying a huge revelation. This is not the case with Goodrich's book and tells us something about his very political intentions. Both the expulsion and flight of Germans from Eastern Europe as well as the death rate in Allied POW camps are facts that have been known for a long time. From the political power lobby organizations of those who fled and were forced out of their homes in 1945 developed in West-Germany to the report of the Maschke Committe on Allied camps in Germany in 1972, there is no \"dark\" or \"secret\" history to uncover here.\n\nRather, what is happening here is typical for Neo-Nazis and holocaust deniers: Citing incomplete facts and narratives or refusing to contextualize them, they seek to either negate the historical record or impose a new narrative. Goodrich is trying very hard in his book to create a moral equivalent between Allied policies and events from post-war history and the Holocaust, essentially arguing that the latter wasn't that bad in light of what the others did.\n\nFurthermore, Goodrich has no real interest in the explaining or even showing the full extent of the history he portrays in his book. While ostensibly adhering to the standards of the profession by supplying citations, he purposefully leaves things out in order to fit his narrative of the Germans being the real victims of WWII because of Allied policies.\n\nLet's take a look how he does this:\n\nThe book starts out in the prologue with building up Erich Koch, former head of the civil administration of occupied Byalistok and Reichskommissar of Ukraine and responsible for – among other things – killing thousands of Poles and Jews. He is built up as heroically mounting a last line of defense in Eastern Prussia against an \"onslaught of hostile Slavs\" in 1944. Though he justifies Koch's harsh measures in his defense, which included shooting civilians trying to flee the advancing front line, he also claims they were not necessary because – paraphrasing – Prussians laughed in the face of the dangers of the advancing Red Army.\n\nEnter Nemmersdorf: Goodrich describes with glee what happened in the first village beyond the border of the then Reich. He cites extensively from documents describing the alleged horrors inflicted by the Red Army upon the villagers of Nemmersdorf, including how the Soviets allegedly nailed women and children to barn doors. Now, Nemmersdorf is not just an obscure example: It is well known among historians for what happened there and especially for the controversy that ensued from it, and for what people like Goodrich like to use this example.\n\nWhat we know is that in Nemmersdorf on October 21, 1944, between 23-30 German civilians were killed. At least 13 of them were shot by a Soviet unit after having been discovered in a German bunker. For the other 10 to 17, the cause of their deaths remain unclear as do the motives of the Soviet troops who shot the 13 civilians in the bunker.\n\nWhen the Soviets had to retreat from the place shortly after and it was taken back by the Germans, Goebbels ministry of propagnda manufactured evidence of Russian atrocities and enhanced the death toll greatly. As we know now through extensive research conducted in the early 1990s, the sources Goodrich cites in his book about Russians nailing Germans to barn doors were made-up by the Nazi newspaper Völkischer Beobachter in order to motivate the German populace to resist more fiercely. They neither match the recollection of survivors of Nemmersdorf nor the official and initial Wehrmacht and NSDAP reports from Nemmersdorf in 1944.\n\nLong used as a symbol for Soviet atrocities, the history of the massacre in Nemmersdorf has since been greatly revised and re-interpretated though the exact reason for shooting 13 civilians still remain unclear.\n\nBut Goodrich isn't interested in that and despite having had access to all this research when he wrote his book, neglects to mention any of it. Rather, he is trying to built a politicized narrative of \"tu quoque\", which portrays the Allies in a negative light in order to rehabilitate the Nazis.\n\nGoodrich isn't really interested in the story behind the Nemmersdorf massacre or in painting a historically accurate picture of it, the expulsion of Germans, or the conditions in Allied POW camps. All the people he cites describing bad conditions, their experience of sexual violence on the hands of the Soviets or their expulsion from their homes are just arguments to build his narrative of a victimization of Germans with the intention of relativizing the Holocaust and German war-crimes and thus rehabilitate Nazism.\n\nThrough purposely omitting and changing facts, sources and interpretations, he shows that his real interest lies not in these stories and unraveling them historically by contextualizing them but in writing his version of a fantasy history that takes suffering from the people forced from their homes and subjected to violence to portray Nazism as a positive thing.\n\nRather than treating history with the seriousness and professionalism it deserves, he just peddles Nazi propaganda, going so far as alleging (also in the prologue), an Allied intention driven by Jews to commit genocide against the Germans. Again, taking stuff out of context or citing it not in full, he twists and turns history to fit his ends and blame Jews. He essentially makes demonstrably false Nazi propaganda his main source.\n\nThis is a typical endeavor of Holocaust deniers and neo-nazis and goes to show that just because a book cites something, it is necessarily true or has the meaning it assigns to it."
]
}
|
[] |
[
"https://www.amazon.com/Hellstorm-Death-Nazi-Germany-1944-1947/dp/1494775069"
] |
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[
"https://www.amazon.com/gp/customer-reviews/R2XBRODYKJSYKY/ref=cm_cr_getr_d_rvw_ttl?ie=UTF8&ASIN=1494775069",
"https://www.amazon.com/gp/customer-reviews/R12GU0UUJGVF44/ref=cm_cr_arp_d_rvw_ttl?ie=UTF8&ASIN=1494775069"
],
[
"https://www.reddit.com/r/AskHistorians/comments/57w1hh/monday_methods_holocaust_denial_and_how_to_combat/?ref=search_posts"
],
[]
] |
|
3094em
|
If written to once and then left turned off (no power, in a dry temperature-regulated environment), how long would flash memory last until you can no longer read it?
|
So you get some brand new high-quality (for the consumer market) flash memory.
You write a large file to it once, and then power it down and store it in a dry, dust-protected, temperature regulated environment, and never use it again.
How long could that data be stored there until it could no longer be read from again?
20 years? 50? 100? 1000? 10000?
The only thing I can find on this assumes that the flash memory is *in regular use*, wherein they come up with around 15 years.
But I'm interested in flash memory as a solution for *long term* storage. Anyone know?
|
askscience
|
http://www.reddit.com/r/askscience/comments/3094em/if_written_to_once_and_then_left_turned_off_no/
|
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"There is no one answer. Each manufacturer makes different claims about the shelf life of their flash memory products. A common estimates is [around 10 years](_URL_0_). A product sheet (from a company I won't mention) that I have next to me claims \"_25 years of daily usage_\", with daily usage clarified later in the sheet as \"_one read, write, erase cycle per day_\". You can see those claims can vary and be quite vague as well, as they are marketing material.\n\nAt this time, I'm not aware of any peer-reviewed study on flash memory longevity experiments to cite."
]
}
|
[] |
[] |
[
[
"http://www.verbatim-europe.co.uk/en_1/page_are-hard-disks-and-usb-sticks-an-alternative-for-storage-or-are-they-threatened-_2_1.html"
]
] |
|
7xj6nk
|
why does water evaporate faster outdoors than indoors?
|
[deleted]
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7xj6nk/eli5_why_does_water_evaporate_faster_outdoors/
|
{
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"text": [
"Yes, temperature. But also other factors, such as humidity and wind.\n\n_URL_0_\n\nThere are definitely less wind indoor, so that's a big factor.\n\nIf you have a puddle in a small room, as the puddle evaporate, the room gets more humid, thus slowing slowing down the evaporation. In the outdoors, the humidity quickly disperses.\n\nMore importantly is surface area. A puddle and water in a glass, of the same volume, the puddle with evaporate faster, even when both are outdoors, or both are indoors.e"
]
}
|
[] |
[] |
[
[
"https://sciencing.com/humidity-wind-speed-affect-evaporation-12017079.html"
]
] |
|
aw7r6c
|
why do pharmacists complete 4 years of post-grad schooling learning about drugs but physicians actually pick the drugs to use.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/aw7r6c/eli5_why_do_pharmacists_complete_4_years_of/
|
{
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"text": [
"Pharmacists are the last line of defense against a patient taking a drug or combination of drug that may be harmful, especially if that patient is taking over the counter drugs/supplements or filling prescriptions from multiple doctors. \n\nBecause of this, knowledge of the function of many drugs and potential drug interactions can be critical here."
]
}
|
[] |
[] |
[
[]
] |
||
5t33d1
|
why is the president immune from the ethics laws, when the ethics in government act of 1978 expressly states otherwise?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5t33d1/eli5_why_is_the_president_immune_from_the_ethics/
|
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"Standard disclaimer: political, keeping bias to a minimum.\n\nThe current President is immune to ethics laws because the majority party at the moment (the Republicans) aren't holding him to those ethics laws.\n\nSimply put: right now, they're a police officer who's blatantly looking the other way as someone's getting mugged.",
"When Congress made these laws, they likely wanted to avoid direct conflict between the branches and the Constitutional problems it might create -- you can imagine an unscrupulous Congress using conflict of interest rules to launch baseless attacks against the president. It never really was an issue, because every president before Trump has acted as if the rules applied to them, both to avoid political problems and because people who run for president generally have an inherent belief in the country and its institutions. By leaving the president and vice president out, you avoid having to answer some tricky questions about separation of powers that might tie up the law in court.\n\nBut now we're in an unusual situation where the president seems indifferent to ethics norms, and there aren't really any mechanisms to constrain him if Congress abdicates is responsibility as a coequal branch of government. Buckle your seat belts.",
"If politicians weren't immune from the same laws that government regular citizens, then these laws could be used to game the system. For example, if the police were allowed to detain politicians for question, then they would simply stop their political opponents, delaying them long enough to ensure they missed their chance to vote.\n\nSo it's the same with ethics laws. If you allow people to challenge someone for everything they do as an ethics violation, then he will be tied up in court all day answering to these charges and unable to perform his duties. \n\nI mean that's what we're talking about here after all. You're asking how there might be a way to stymie Trump for the next four years by tying him up in court 24/7. Now you might think you're being clever, but you have to remember that when the shoe is on the other foot, your opponents will do the same exact thing to you. \n\nThink of it in the context of executive orders. You hate these things so much when Trump uses, but you never gave a second thought to them before when Obama was doing them. So in this same way, be careful what you wish for, because you might just get it. ",
"The President and Vice President, Congress and federal judges. are specifically exempted from having to follow the same ethics laws as employees. Congress sets their own ethics rules. Following is the relevant part of the law where they are all exempted:\n\n“Except as otherwise provided in such sections, the terms ‘officer’ and ’employee’ in sections 203, 205, 207 through 209, and 218 of this title shall not include the President, the Vice President, a Member of Congress, or a Federal judge.”",
"No one is actually stating what should be obvious, our current president is **not** in violation of the Ethics in Government Act. There are only two reasons you would think he would be in violation: you think the act has some generally ethical clause in it, or you think Trump has not disclosed his financial reports.\n\n*Option 1: you think the act has some generally ethical clause in it.* The Ethics in Government Act covers the disclosure of financial reports, a few other technical things, and establishes oversight of this process. That's it. It in no ways says things like \"The president must be ethical\". This act is solely about financial disclosure, nothing else. Speaking of that...\n\n*Option 2: you think Trump has not disclosed his financial reports.* Well guess what, he has. [Here](_URL_0_) it is, go read it yourself.\n\nYou may have heard that Trump has been refusing to release his tax returns. That is correct, he has refused to do that even though most other Presidents have. *But* that is not legally required. Trump has done everything he legally had to do to disclose his finances, thus he is not in violation of the Ethics in Government act.\n\nHopefully that makes sense to you. ",
"Many of the checks and balances that were created to prevent corruption have become rubber stamps and in many cases actively work against what they were inteded to do like the electoral college and its electors... essentially most of our checks and balances are now used as tool to exercise control by the party in majority so they can stay in power",
"The simple answer is that the only real limit on any President's powers and actions is a united Congress' willingness to impeach him. Laws mean nothing if no one is willing to enforce them...",
"Separation of powers is how. (Dont believe the hype)\n\nCongress cant pass a law that limits the constitutional enumerated power of the executive branch (they need an amendment to do that) and since the Constitution states quite plainly that power of the executive is vested with the president. Meaning that all of the powers of the executive branch are contained solely with the president, congresses only redress with the president is to impeach him. Since impeachment usually requires high crimes and misdemeanors, and as a practical matter requires overwhelming support, any other \"ethics\" sanctions are impossible to levy on the president.\n\n",
"The ethics in government law is fairly limited in what it does. \n\nAlso, in a fight between the president and Congress, the constitution is the controlling document. That has supremacy in how things get handled. The Constitution allows impeachment for \"high crimes and misdemeanors\" and it also allows for significant Congressional oversight - if they choose to exercise it. \n\nThey are not choosing to exercise it. Congress has the power. It's just not using it. "
]
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x0fib
|
What are some lesser known Genocides in World History?
|
I'm taking a class about the Holocaust right now. We've also discussed the Armenian and Cambodian Genocides a bit. Any other big ones?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/x0fib/what_are_some_lesser_known_genocides_in_world/
|
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"The definition of Genocide is VERY slippery and controversial, but if we can at least agree that it involves intentionally attempting to wholly eradicate a specific ethnic group, then I would mention the Zunghar Genocide perpetrated by the Qing Dynasty as one of the lesser known tragedies in world history.\n\nThe Zunghars were an Oirat Mongol people who ruled a state in modern day Xinjiang in the 17th and 18th centuries. In 1757 the Qianlong Emperor and the Qing Dynasty defeated the Zunghars and conquered Xinjiang in the name of ending the nomadic threat. Initially Qianlong attempted to divide the region into six or more vassal states, but the Zunghar chieftan Amursana rebelled and attempted to unite the region under his own rule. Qianlong was enraged by this betrayal (Amursana had fought with the Qing in the previous campaigns).\n\nAfter the onset of Amursana’s rebellion, Qianlong ordered the wholesale massacre of the Zunghar people. The Emperor’s commanders resisted the order, but Qianlong was adamant. “Show no mercy at all to these rebels,” he wrote his generals, “Only the old and the weak should be saved. Our previous campaigns were too lenient.” In no uncertain terms, Qianlong stressed that it was necessary to “completely exterminate them.” All able bodied men were to be executed, while old men, women, and children were to be forced into slavery and stripped of their Zunghar identity. Qing forces hunted down rebel bands and slaughtered them by the thousands. Deliberate starvation tactics were used to kill tens of thousands more.\n\nAll told, of the roughly 600,000 Zunghars before the massacre, 40% died of smallpox, 30% were killed by Qing forces, 20% fled to neighboring Russia, and the remaining 10% were enslaved and stripped of their identity. Xinjiang was dramatically depopulated, and the Zunghars ceased to exist as a people. \n\nPeter C. Perdue, a professor at Yale university and the main source for this post, was the first to label this event as a Genocide in his 2005 work *China Marches West*. His claim is supported by Central Asian and Xinjiang Historian James Millward, a professor at Georgetown, in his own 2007 publication *Eurasian Crossroads*.\n\nSources:\n\nMillward, James. *Eurasian Crossroads*, 2007, 94-96.\n\nPerdue, Peter C. *China Marches West*, 2005, 282-287.\n",
"[The Herero-Genocide](_URL_0_) is in my eyes a very important part in understanding the Holocaust. It's the first Genocide of the 20th century and it already has characteristics that also make the Holocaust so horrible - the inhumane barbarism and technical efficiency. \n\nNot enough people know about it.",
"One that I was particularly shocked by was what happened in [Congo](_URL_0_) under Leopold II. Leopold II took complete control over Congo as an absolute monarch under the guise of being a humanitarian, and exploited its people so much that he caused millions to die. The death toll is uncertain and varies from 15% to 75% depending on who you ask. (between 4,5 and 22 million)\n\nThe reason why this shocked me so much was because this man still has statues of him standing here in Belgium.\n\n > There has been a \"Great Forgetting\", as Adam Hochschild describes in his book King Leopold's Ghost: \"The Congo offer a striking example of the politics of forgetting. Leopold and the Belgian colonial officials who followed him went to extraordinary lengths to try to erase potentially incriminating evidence from the historical records.\"\n\n > Remarkably **the colonial Royal Museum for Central Africa (Tervuren Museum) does not mention anything at all about the atrocities** committed in the Congo Free State. The Tervuren Museum has a large collection of colonial objects but of the largest injustice in Congo, Hochschild wrote: \"there is no sign whatsoever.\" Another example is to be found on the sea walk of Blankenberge, a popular coastal resort, where **a monument shows a colonialist with a black child at his feet (supposedly bringing him \"civilization\")** without any comment.",
"I would say the Genocides that occured in the Americas during European colonization. It was estimated that between 2.1 and 18.1 million native Americans were killed in now a days United States, not counting South and the rest of North America \n\n[Source](_URL_0_)",
"_URL_0_\n\nThe Albigensian / Cathars Crusade",
"To this day,some historians and politicians claim the [War in Vendée](_URL_0_) during the French revolution was a genocide. It sure is a very loose use of the term *genocide*, and most consider this event as a case of civil war, but this debate pops up now and then among historians."
]
}
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[] |
[] |
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[],
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[
"http://en.wikipedia.org/wiki/Genocides_in_history#Americas"
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"http://en.wikipedia.org/wiki/Albigensian_Crusade"
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] |
|
c3jenz
|
why, with all our advancements in telecommunications and phone technology, has phone call audio quality stayed virtually the same as ten or twenty years ago?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/c3jenz/eli5_why_with_all_our_advancements_in/
|
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"If you talk about landlines or anything that is talking to landlines: That is a dead technology, don't expect anything there.\n\nIf you talk about VoIP: That is much better than years ago, with a better sampling rate and wider spectrum they capture.\n\nHowever, that is part of the problem, the biggest problem is the transfer of the voice of the speaker to the microphone: Some microphones are crap (cheap headset), or not at the right place (laptop, or not close by the mouth) or interference with the environment (wind, background noise).\n\nThere is only so much technology can fix :-/\n\nYou won't get movie quality because that's rerecorded in the studio.",
"Of all the things that cell phones do better than land lines, the sound quality was so much better.",
"In simplest terms; because the telephone system is an internetwork of individual links, it is limited by the least capable link in the system. Think of having a road between two cities that starts out as a five-lane Interstate highway, drops to a dirt road, then goes back to a five-lane highway and then arrives at the destination - the traffic is limited to the capacity of the stretch of dirt road in the middle.\n\nIn standard telecoms that limitation is the enduring use of [G.711 encoding](_URL_3_) to convert analog sounds from the two ends of the call into digital information that will be carried over digital [trunk circuits](_URL_5_) in the middle. Those circuits, at least in North America, are built around the [T-carrier architecture](_URL_0_) (with the ulaw variant of G.711), which has a hard limit of 64kbps of information per circuit which, skipping over a whole bunch of technical stuff, translates into only carrying sounds between [300 and 3400Hz](_URL_4_) \\- everything else within the typical range of hearing of 20–20,000Hz is simply discarded.\n\nVarious methods of delivering [wideband audio](_URL_1_) over conventional digital telephone networks do exist (eg. [G.722](_URL_6_)), but if the call will eventually terminate on a conventional analog telephone (or cellphone) then the extra effort to capture and transmit that extra audio information just goes to waste as the signal must be [transcoded](_URL_2_) to meet the capability of the lowest common denominator in the end-to-end circuit.\n\nOn the other hand with pure VOIP calling, for example with Skype-to-Skype calls, most of the internetworking issues are eliminated as the sound is transmitted entirely as a stream of data which is controlled exclusively by the two ends of the call, and so the system can transmit as much audio spectrum as the designers wish.\n\n & #x200B;\n\nedit: goodness, gilding? I'm flattered!",
"Cell phone audio quality used to be remarkably clear. As good as landline communication. But that was when it was analog and a full three watts.\n\nModern cell phones (the last 15 years or so) use digital, low power signals. And the quality is pathetic.\n\nProbably one of the really big reasons people don't like to talk on the phone in modern times is because the quality is so horrible.",
"The audio quality of a mobile phones is based on following aspects: note this applies to both devices, originating and terminate end.\n- bandwidth assigned to the voice channel\n- vocoder technology used\n- microphone quality of mobile phone\n- speaker of device\n\nNow, the best technology to measure Voice quality is based on a set of standards, which for VoIP technology, is PESQ (google it). PESQ measures the variance of signal and creates a score using various large database that has relative voice metrics to what it listens to. It scores it based on a 1-5 score. 1 means not understandable and 5 being it sounds perfect (original audio from originating device)\n\nSince the 1990s, the quality has improved by 1 point. In 2G and 3G technologies, it was 3-3.5. In 4G, it has been improved towards 4.2-4.5. Note this is log scoring, so as you get closer to 5 it’s a huge incremental improvement. \n\nOne commenter brought up a good technical specs on the G.711.",
"Landlines haven't improved much, unless it's two VOIP lines through good handsets. If they're older and/or cheap home phones, then quality wouldn't improve much. \n\nNow, newer cellphones on the other hand is a different story. With VoLTE/HD voice(depending on branding, it can be called a couple things but it's the same principle) quality is vastly improved. Voice over LTE can have sampling rates up to 16Khz, which is what is typically used for normal video streaming. Old standard cell calls were a rather abysmal 3.5Khz range, which is what causes the muffled quality. \n\n Now, of course there's going to be some quality loss as it's just small cheap mics in cell phones, and earpiece speakers aren't particularly high fidelity, but it's leagues better than 10 years ago.",
"That's patently untrue. HD Voice / VoLTE has vastly superior audio compared to anything else prior. I do miss the old landlines, where you could hear yourself talking in the earpiece tho.",
"phone network operators are today internet service providers (simplified a little) - millions of calls go through their data network every sec. so they want to keep costs down and that means limiting the per-call bandwidth as much as possible - that in turn entails high compression of the audio which leads to poor audio quality.\n\nbasically the operators want the audio quality to be just good enough - anything more than that is a waste of their money.\n\nTL;DR\n\nit's from the same reason we don't go to the moon anymore (at least not manned missions) even though we could do it - economy. the operators are trying to max profits, not audio quality.",
"Fantastic explanations here! My attempt to simplify it further: \n\nPhones may not have super high quality right now, but it's usually good enough to understand people talking, and that's all you really need for phones, so it isn't worth spending money to improve.",
"TL;DR you’re limited by the lowest common denominator. To get the amazing call quality you can get over 4G, you need everything between you and the person you’re calling to be capable of handling the high quality calls. If even one link in the chain isn’t capable, you’re going to be limited to the capability of that link",
"Lol, you clearly weren’t making many phone calls 20 years ago. \n\nQuality has undeniably improved.",
"Audio quality on smartphones (especially iphone) is great. The noise cancelling is incredible too, but people don't even realize that it's doing it but these phones have lots of microphones for that purpose.\n\n & #x200B;\n\nThe limitation is the speaker quality on the tiny phones",
"I dunno what phone you use but phone call quality has increased a ton for me in the last decade. Lots of the calls I have now are the HD audio calls.",
"Because it has been studied which frequencies are necessary to make speech understandable and only those frequencies are being transmitted to save bandwidth. We could easily switch to higher quality but there is no need. I suspect higher quality audio will be a thing when VoIP becomes easier with the new 5G networks.\n\nI am bewildered by some of the answers here claiming that the reason the quality is limited is the infrastructure. No, that is not true. The infrastructure has been *designed this way* based on the needed frequencies. We have created these limitations on purpose to save the cost.",
"Using Oculus VR, my gf and I both hear as if we were in a recording studio. Unbelievable sound quality.",
"It hasn't stayed the same it is actually worse now than it was 20 years ago when I was a telecommunications tech.\n\nThe main reason is VOIP (Voice Over IP). Compression algorithms used for VOIP concentrate very heavily on the audio frequencies mostly used in speech.\n\nTherefore anything outside of those frequencies suffers serious degradation. Take for example music on hold. These days most music on hold is simply painful to hear. Also children's voices and higher pitched persons voices.\n\nSo than your local telecoms trying to squeeze as many voice channels as they can over existing paths.",
"Am I wrong, that I feel that it actually has gotten worse with smartphones? When I had my dumbphones, I never had to ask the person to repeat him/herself. With smartphones it's regularly an issue. The person sounds real quit (yes, volume is wat up), distant, or there is just loads of interference or interruptions.",
"because it hasnt. compare a voice quality from old school landlines/early cellphones to the hd voice quality of today. OP you are clearly ignorant to the fact the voice quality has indeed changed over the decades.",
"50% of the answer is, and always has been, \"because it's good enough\". They've done a hundred studies on the minimum viable level needed to carry on a conversation and often it makes little sense economically or environmentally to overbuild beyond what's actually needed.\n\nThe other 50% of the explanation changes as the trends in handsets changes. In 2019 the desire to have your slim phone fit neatly in your pocket is actually hurting the quality of your phone calls quite a bit. It's the ear piece more so than the mic that's letting you down. There are some inescapable physics there that require the ear piece to either be larger than it currently is (picture a good pair of headphones) or more directly sealed to your ear (picture a good set of ear buds).",
"We have VoIP now. And wifi calling. And other such things. But they only work if both people in the call have it. My work phone has ViOP calling. But my private does not."
]
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"https://en.wikipedia.org/wiki/T-carrier",
"https://en.wikipedia.org/wiki/Wideband_audio",
"https://en.wikipedia.org/wiki/Transcoding",
"https://en.wikipedia.org/wiki/G.711",
"https://en.wikipedia.org/wiki/Voice_frequency",
"https://en.wikipedia.org/wiki/Trunking",
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2q82bn
|
How fictitious is the current modern perception of the samurai?
|
Ask asked above, the modern perception of the samurai is often of a noble warrior who holds honor and integrity above all. However, I have often heard that the bushido code and things of the sort were all blatant lies of propaganda to make Japan's history look better than it actually was.
How were samurai truly perceived back in the earlier days of the Meiji era, etc.?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2q82bn/how_fictitious_is_the_current_modern_perception/
|
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"Early days of the Meiji era? The 廃刀令 (Order to restrict carrying of sword) was issued in Meiji 9, 1876, with the earliest discussion to going all the way back in Meiji 3, 1870.\n\nThe order restricted carrying to sword to soldiers and police.\n\nOn top of that, the Meiji restoration had a important policy that is to strip the power of the local lords (and samurais by extension), that was policy that long stood since Meiji 4.\n\nI think you might want to revise the era in the question, and I think someone else should be able to answer the question. But your question is definitely not applicable in the vast majority of the Meiji era. Seeing that most of them were stripped their powers pretty early. I unfortunately lack in-depth knowledge in anything pre-Meiji.",
"I'm talking about during the Sengoku Jidai and the Tokugawa periods.\n\nBushido was more a question than an answer to many samurai and many were practitioners of Zen Buddhism.\n\nBut much like European chivalry there was a common idea of Bushido that ran through the warrior class and was adhered to to greater and lesser degrees by various samurai.\n\n\nDuring the Sengoku Jidai (literally the Age of the Country at War), when Japan was unifying under one Shogun, samurai were mostly soldiers (bushi), and most saw action as the country underwent a series of wars and battles as multiple different Daimyo tried to seize power all across Japan.\n\nAfter Tokugawa took power his reforms were designed to limit power of the Daimyo so while he demanded Daimyo to retain certain levels of samurai bushi he also taxed them more in various ways and slowly strangled them with expenses like maintaining certain levels of samurai who weren't allowed to go to war unless the Shogun decided to war, which was rare as war during the Tokugawa era was very rare compared to the Sengoku Jidai.\n\nThus, samurai ended up less soldiers and more retainers, although fighting schools became more common as did duels and duelists like the great Musashi. Bushido remained popular amongst some and the famous real life 47 Ronin did actually commit ritual suicide to protest th unfair death of their former master after they sought revenge on the man they held responsible for their master's demise.\n\nThe famous book Hagakure, the Book of Leaves (or hidden leaves), was written in the early 1700's and outlines bushido as a series of short stories used as teaching examples from conversations between two samurai, a young man, the author, and an older master. It talks about the change in society from a country in constant war to a more peaceful one and seems to be searching for how a samurai should live with Bushido during a peaceful time like during the Tokugawa Shogunate.\n\nIt's also important to note that right after Tokugawa Iieyasu unified Japan that there were hundreds of thousands, if not a million ronin, or disposed warriors, from the losing Western Daimyo, roaming the countryside. Many samurai believed that if your master died and you had no one to serve you should commit seppuku. And obviously, thousands did not, and thus failed to follow the most hardcore tenants of the code.\n\nIt's clear from books like Hagakure, numerous examples of death poems and records of ritual suicide, and many examples of those who did not do such things, that samurai varied from person to person and while some took Bushido very seriously others did not, just like many codes and beliefs in human life. :-)"
]
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|
[] |
[] |
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[],
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|
5sf2td
|
why can soup (with meat) be stored at room temperature?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5sf2td/eli5_why_can_soup_with_meat_be_stored_at_room/
|
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"If it is in a sealed can, it is safe because the cans were superheated to kill all bacteria they might have had in them and since then have had no way to get outside bacteria in.\n\nThe issue with keeping food warm too long is that it allows bacteria to thrive. But if there are no bacteria to begin with and no way for any to get in, it is safe.",
"Pasteurization. The food is sealed in the cans and then heated, killing anything living inside that would have otherwise caused the food to spoil. As long as the can remains sealed the contents remain sterile. ",
"Because it is canned.\n\nThe canning process involves boiling the cans or placing them in a pressure canner. Sometimes preservatives or acids (like lemon juice) are added. The can is airtight, so the bacteria that make food rot are unable to grow. \n\nOnce the can is punctured, the food is no longer sealed and the food will begin to spoil."
]
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|
[] |
[] |
[
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||
b7urog
|
why do gas giants have such strong gravities?
|
Like Jupiter for instance or Saturn. They're gas giants that are huge I'll grant, but why so much gravity? Given that they're mainly gas, wouldn't their density be very low? And if their density is low, how do they have so much gravity?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/b7urog/eli5_why_do_gas_giants_have_such_strong_gravities/
|
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"Their density might be low, but they are still massive. The \"force\" of an object's gravitational field depends not on density of an object but on raw mass. For example, if you crushed the earth down to a black hole maybe a few meters across the orbit of the moon and any other satellites would stay the same as they are today. ",
"Their density is lower, but they're also vastly bigger than earth or similar planets. The increase in volume means that they still have a lot more mass than smaller, denser planets, and that's what dictates their gravitational pull. ",
"Gravity is determined by mass, not density. Jupiter is 318 times more massive than Earth. Saturn is 95 times more massive than Earth. Thus, despite being far less dense, they nonetheless have far stronger gravity. "
]
}
|
[] |
[] |
[
[],
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|
flpi85
|
How does a respiratory infection spread from cell to cell inside of a host?
|
I understand how the virus binds to a specific cell, invades and then replicates itself many times over.
What I'm asking is how the virus spreads beyond that cell. Do influenza and corona viruses spread only to neighboring cells in direct contact with the initially infected cell, progressing out in a uniform manner?
Or do infected cells burst in all directions, infecting neighboring cells but also injecting progeny virions into the periciliary and mucous layers where the infection can spread more widely?
|
askscience
|
https://www.reddit.com/r/askscience/comments/flpi85/how_does_a_respiratory_infection_spread_from_cell/
|
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"You almost had it in the first section. After the cell produces many copies of the virus, the new virus particles head toward the membrane of the cell and push out, taking part of the membrane with them to provide a protective layer. Those new virus particles then all go out and infect new cells and the cycle continues on and on until either the immune system catches up or the host dies."
]
}
|
[] |
[] |
[
[]
] |
|
5h1u0f
|
why is the bell pepper so big, while it's mostly empty on the inside?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/5h1u0f/eli5_why_is_the_bell_pepper_so_big_while_its/
|
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"text": [
"It's the skin and outer flesh of the pepper that you use to cook with. People are more likely to buy larger peppers because it gives them most flesh to cook with, even though it's just empty space inside. Bell peppers are cultivated by humans, they were bred to be as plump and big looking as possible like chihuahuas were bred to be small. The inside doesn't matter, you scoop it out and throw it in the trash.",
"The plants and animals that we use for food have nearly all been domesticated and bred to fit human needs and desires. They are much different than the wild ancestors which were much smaller and denser.\n\n_URL_0_\n ",
"I've always wondered is it air inside there, or vacuum or what? Is the skin permeable to air?",
"I'm curious now when corn was changed to the more modern variety.\n\nThe 3rd grader image of the \"traditional thanksgiving\" in my head with native Americans and big bowls of corn is now cluttered with thoughts of little weeds. "
]
}
|
[] |
[] |
[
[],
[
"http://www.sciencealert.com/here-s-what-fruits-and-vegetables-looked-like-before-we-domesticated-them"
],
[],
[]
] |
||
2gm99i
|
What was the plan for Nunavik (northern Quebec region governed by the Inuit) if Quebec had gained independence in the 1980 referendum? Did the separatists say what they would do about the JBNQA (the 1975 agreement giving the Inuit control over the northern third of the province)?
|
I specified the 1980 referendum to not run afoul of the 20 year rule.
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/2gm99i/what_was_the_plan_for_nunavik_northern_quebec/
|
{
"a_id": [
"ckktyb0"
],
"score": [
6
],
"text": [
"The question is a bit vague, inasmuch as it does not specify who was doing the planning.\n\nOn the side of the PQ, the notion of Québec partition was simply deemed untenable, and that international law was a sufficient garantee against it ([source](_URL_4_)).\n\nHowever, at the federal level, the opposite was at least considered. For instance the PM at the time was quoted as stating that if Canada was partitionable, it followed that it must also be the case for Québec (Charron, Claude G., La partition du Québec: De Lord Durham a Stéphane Dion. (Montreal: vlb éditeur), 1996, p. 167.)\n\nMeanwhile, the Inuit themselves wanted nothing to do with a sovereign Québec, and said so through some of their chief negociators, such as Zebedee Nungak and Charlie Watts. For one thing, they worried about losing their ties with the Federal government and with other Inuit in the rest of the canadian arctic ([source](_URL_3_)). Furthermore, the Inuit had long-lived concerns that the Federal responsibility to consult them as aboriginal people was steadily eroding, as witnessed by the fact that they had not been consulted when Nunavik was transferred to Québec in 1912 ([source](_URL_1_)). The also saw the prospect of being excluded from their (relatively) new Canadian identity into yet another new country through a referendum where their voices would not matter (through sheer demographic weight) as going against their own aspirations to self-determination (ibid.). As witnessed from political cartoons of the time (see: From Eskimo to Inuit in 40 Years, 2011, published by Inuit Tapiriit Kanatami, p.78), passage to a sovereign Québec was also seen as fraught with the risk of forced cultural assimilation. One such image, for instance, shows a lone Inuk facing René Lévesque backed by marching ranks of language police bearing the “bill 101” standard.\n\nAlthough OP did not ask about other aboriginal nations, the Cree (for instance) were also very vocally opposed to remaining within a sovering Québec and would have sought partition as well, using arguments similar to those voiced by Pierre Trudeau (see p. 50 [source](_URL_0_.) \"Coon Come souligne que le Québec revendique le droit historique de déterminer son avenir sur la base d'une langue, d'une histoire et d'une culture distinctes. Comment, demande-t-il alors, le Québec peut-il affirmer que ce droit ne s'applique pas aux Cris? Les Cris n'ont-ils pas de langue, d'histoire et de culture distinctes?\")\n\nHow does it all add up? As far as can be inferred from existing sources, a newly independent Québec would have had to defend its territorial integrity to a refractory Canadian Government backed by a local population which felt more attachment to its Canadian identity and wished to preserve its territorial integrity while pushing for its own self-determination. Can any of this be called a plan though? A recent book on the 1995 referendum [recent book on the 1995 referendum]( _URL_2_) showed that neither the yes side nor the no side had a coherent and well thought out strategy for dealing with “Day 1” after a “Yes” vote (I hope I'm not violating the 20 year rule by referring to such recent work). One may perhaps surmise that such was also the case in 1980, and that a “Yes” would have been followed by unforeseen chaos and partisan infighting.\n\nEDIT: Also worth mentionning that the James Bay Agreement does not simply \"give the Inuit control over the northern third of the province\" as OP suggests. It gives them ownership of some lands (Cat 1), and codifies their right over hunting and fishing in Cat 2 and Cat 3 lands. It also sets the basis for the regional political and administrative structures. We are a far cry here from Inuit governmental autonomy."
]
}
|
[] |
[] |
[
[
"http://www.archipel.uqam.ca/3364/1/M11459.pdf",
"http://www.queensu.ca/iigr/pub/archive/aboriginalpapers/positionpapers/PositionPaperCompletingCanada.pdf",
"http://www.editions-homme.com/confessions-post-referendaires/chantal-hebert/livre/9782761940924",
"http://www.global-economics.ca/dth.chap7.htm",
"http://en.wikipedia.org/wiki/Partition_of_Quebec#Arguments_against_partition"
]
] |
|
4dwuxg
|
why is ancestry from spain important to the u.s. census (hispanic) but ancestry from other latin cultures like italy or portugal isn't?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/4dwuxg/eli5why_is_ancestry_from_spain_important_to_the/
|
{
"a_id": [
"d1v045x",
"d1v1bne",
"d1v7t2t"
],
"score": [
25,
5,
3
],
"text": [
"With regard to the U.S. Census, Hispanic doesn't mean from Spain -- it means people from Mexico and Latin America, ie. Spanish speakers. Hispanics make up about 17% of the U.S. population currently.",
"The significant portion of the population that would be considered Hispanic are not ancestrally from Spain. They only inherited the Spanish language from their Spanish conquerors.",
"The US Census' definition of Hispanic is \"a person of Cuban, Mexican, Puerto Rican, South or Central American, or other Spanish culture or origin regardless of race\". Mexico/South America/Central America populations derived from the Spanish.\n\n\"White\" is a catch-all: \"A person having origins in any of the original peoples of Europe, the Middle East, or North Africa\"\n\nAlthough there is the \"two or more races\" option, so it gets a but muddled."
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
12g3zr
|
why do i need glasses if i've got irises?
|
The iris of my eye is supposed to focus the light coming into my eye through the pupil onto the retina. There's still plenty of room left for my pupils to expand and contract more than they do, so why do I need glasses?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/12g3zr/elif_why_do_i_need_glasses_if_ive_got_irises/
|
{
"a_id": [
"c6uqo5d",
"c6uv3s1"
],
"score": [
15,
3
],
"text": [
"The Iris doesn't focus, it controls how much light enters your pupil. The lens focuses by changing shape with tiny little muscles. You need glasses because the lens is too rigid and the muscles are too weak.",
"To answer your question, I'm going to need a lot of pictures, so get your RES ready.\n\n[Diagram](_URL_1_)\n\nLets pretend that the light coming into the eye is running parallel, (in straight lines) towards the eye. Now, all of the things that you see have to have light that gets to the back of the eye, on the [retina](_URL_3_). This light has to go through some cool tools to get there first.\n\nWhen light hits the eye, it goes through the outer lens of the eye (called the [cornea](_URL_6_)) . This acts as the first impact of the light. Now, this bends light a little bit so that it is more focused on the next part, and serves as a light collector, so the light is still mostly parallel.\n\nAfter the outer lens, Then the light coming in has to go through the iris. Now, you might think that the function of the iris is to focus light, when in fact *the purpose is to change the amount of light allowed into the eye itself*. When the iris is narrowed, less light can come through, because if the light is parallel, less light makes it through the gap and more hits the colored iris. This is why irises get small when you stare at a light (less light needed), or get very large when you are in a dark space for a long time (more light needed)\n\nNow, the action happens at the lens, which is behind the iris. Now, the lens can change shape to change the way the light bends as you can see [in this image](_URL_0_). [Source](_URL_2_). When something is closer, it has to bend the light more to get it into focus on a small point, so the lens gets thicker, and when something is farther away, it doesn't have to bend as much, so it gets thinner. Pretty cool, huh?\n\nNow, to answer your question about glasses. Glasses are needed when the lens cannot bend light correctly, because the lens or cornea is misshapened, or the eye is not the shape that the lens is built for (called axial myopia if someone is nearsighted). In myopia, the image is actually focused *in front* of the retina, as seen in the [top half of this image](_URL_5_). Glasses are shown on the bottom half, and they alter the incoming light to change the focal distance of the image. By adding an artificial lens in front of the eye, it becomes possible to see correctly by changing the distance from the Lens that the image is focused. [Source](_URL_4_)\n\nI hope that answered your question."
]
}
|
[] |
[] |
[
[],
[
"http://upload.wikimedia.org/wikipedia/commons/thumb/8/81/Focus_in_an_eye.svg/250px-Focus_in_an_eye.svg.png",
"http://upload.wikimedia.org/wikipedia/commons/9/9a/Anatomy_and_physiology_of_animals_How_light_travels_from_the_object_to_the_retina_of_the_eye.jpg",
"https://en.wikipedia.org/wiki/Lens_(anatomy\\)",
"http://en.wikipedia.org/wiki/Retina",
"http://en.wikipedia.org/wiki/Myopia",
"http://upload.wikimedia.org/wikipedia/commons/thumb/3/30/Myopia.svg/220px-Myopia.svg.png",
"https://en.wikipedia.org/wiki/Cornea"
]
] |
|
1bu8t9
|
how google stores caches of so many websites
|
It seems like an immense amount of data. One cannot simply download an internet.
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1bu8t9/eli5_how_google_stores_caches_of_so_many_websites/
|
{
"a_id": [
"c9a4vd7"
],
"score": [
2
],
"text": [
"There are a few methods that Google uses.\n\nThe primary one is that Google spends plenty on continually adding more servers, server space, and improving their ability to manage that ever-growing space.\n\nAlso, copies of crawled websites compress better than many types of data. Google once released that they're able to compress crawled websites to an average of 11% of their uncompressed size.\n\n[There's also this theory of where they get all that server space.](_URL_0_) ;)"
]
}
|
[] |
[] |
[
[
"http://www.joyoftech.com/joyoftech/joyarchives/301_999/669.html"
]
] |
|
44w34j
|
if alcohol helps kill bacteria and fights bad breathe (like mouthwash), why does your breathe smell like death after a night of drinking ?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/44w34j/eli5_if_alcohol_helps_kill_bacteria_and_fights/
|
{
"a_id": [
"cztb5k9",
"cztbmt0",
"czte2w4"
],
"score": [
13,
2,
3
],
"text": [
"Because the alcohol doesn't kill ALL of the bacteria in there and those little greebly bastards reproduce right quickly. \n\nThen there's good odds that you didn't brush your teeth before passing out into a drunken stupor. That means there's all sorts of dilute sugar solution from the beer or wine that you drank (the alcohol would have evaporated away), coupled with oily residues and starches from the full bag of Doritos and breaded chicken wings that you ate earlier in the evening. This is wondrous foodstuff for the bastards and they go right to town, producing all sorts of atrocious-smelling byproducts as they digest them.",
"Because the alcohol you drank the night before still lingers in your body, as your liver fights to process it. Lingering alcohol molecules from your blood pass through your lung walls and are exhaled. This stale, boozy breath might be what people experience.",
"the_original_Retro and tminus7700 have dealt with the fundamentals of this issue (alcoholic concentration, other ingredients in the alcohol), but there is another relevant issue.\n\nYour saliva takes care of all the anti-bacterial activity in your mouth. After a night of drinking, your body is dehydrated and therefore produces less saliva, which allows the bacteria in your mouth to grow unabated, which leads directly to bad breath.\n\nThis can be tested by checking the breath of a person who sleeps with their mouth open, as that allows their mouth to dry out and their breath will therefore smell worse in the morning than someone who sleeps with it closed. "
]
}
|
[] |
[] |
[
[],
[],
[]
] |
||
hhjeo
|
How do water-powered batteries like this work? Are they pretty much useless?
|
[Here's](_URL_0_) an example.
It says it can only be charged 5 times, which is the only downside I see. I've never used one though. I guess if they're cheaper than regular batteries **and last almost the same amount of time** then they're definitely worth it.
Would it be possible to improve that technology to make it so they can be recharged many more times?
|
askscience
|
http://www.reddit.com/r/askscience/comments/hhjeo/how_do_waterpowered_batteries_like_this_work_are/
|
{
"a_id": [
"c1vgf1d",
"c1vghtw"
],
"score": [
5,
3
],
"text": [
"take a look at [this](_URL_0_) - it's not powered by the water, that's just the electrolyte. the power comes from the dissimilar metals which make up the anode & cathode, at least one of which will be consumed by the reaction. they're not useless, but yeah, there are more efficient ways of making a battery.",
"It's not water-powered, it's a [water-activated battery](_URL_0_). In this case magnesium is providing the electrons. As the battery soaks with water, ions make the water electrolytic, and current can flow. Refilling with water doesn't recharge it, it just allows whatever magnesium is left to be oxidized. These have a very low power output, which limits their use. And they're apparently $58 for 6 batteries, so buy heavy metal batteries and invest the rest in alternative energy."
]
}
|
[] |
[
"http://www.japantrendshop.com/nopopo-eco-waterpowered-aa-batteries-p-546.html"
] |
[
[
"http://en.wikipedia.org/wiki/Lemon_battery"
],
[
"http://en.wikipedia.org/wiki/Water-activated_battery"
]
] |
|
cqy2cw
|
how did “hello” become the default greeting when you answer the phone?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/cqy2cw/eli5_how_did_hello_become_the_default_greeting/
|
{
"a_id": [
"ex0gqna",
"ex0h5iz"
],
"score": [
17,
4
],
"text": [
"Nobody liked 'Ahoy!' which is what the creator of the telephone wanted the standard greeting to be.",
" > The use of hello as a telephone greeting has been credited to Thomas Edison; according to one source, he expressed his surprise with a misheard Hullo.[11] Alexander Graham Bell initially used Ahoy (as used on ships) as a telephone greeting.[12][13] However, in 1877, Edison wrote to T. B. A. David, president of the Central District and Printing Telegraph Company of Pittsburgh:\n\n > Friend David, I do not think we shall need a call bell as Hello! can be heard 10 to 20 feet away.\n\n > What you think? Edison - P.S. first cost of sender & receiver to manufacture is only $7.00.[14]\n\n > By 1889, central telephone exchange operators were known as 'hello-girls' because of the association between the greeting and the telephone.\n\nAs /u/ChoadyWalker says, this was in contrast to Bell's desire that the greeting be \"Ahoy-Hoy\"."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1p8yyx
|
What are some salient points about the West Coast Salish peoples and associated cultures that should be more well known?
|
As a Washington resident, I feel like I should know more about the local native culture. What do you historians feel were their most notable accomplishments? How did they compare to European civilizations at a similar level of economic and technical development, or with the native cultures around them?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1p8yyx/what_are_some_salient_points_about_the_west_coast/
|
{
"a_id": [
"cd0f68o"
],
"score": [
2
],
"text": [
"What really differentiated the people of the PNW (Kwakiutle, Haida, Coast Salish, Squamish, ect. ect.) from many of the other tribes around North America was how settled they were, compared to even the most agriculturally based Aboriginal societies such as the Iriqouis in the east. \n\nBecause they (and we) live in a region that is so abundant with food, their survival didn't depend on depend on following migratory buffalo like the Plains tribes or the Eastern agricultural tribes, who still had to migrate settlements from time to time due to soil degradation. As a result of this relative settlement, camps in the PNW became much larger, and social structures became more complex, with tradesmen and artisans, as opposed to simply just hunters. What also developed was a social hierarchy, including slavery (for comparison with European civilization at the time). \n\n "
]
}
|
[] |
[] |
[
[]
] |
|
7mh1k1
|
i'm told that my daughter (14 months) shouldn't have red meat, because it's hard for her body to process. why is red meat harder to digest than other meats?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/7mh1k1/eli5_im_told_that_my_daughter_14_months_shouldnt/
|
{
"a_id": [
"drtvx6l"
],
"score": [
2
],
"text": [
"A well respected pediatrician at my medical school taught me that all types of meat were appropriate early foods (or beikost) as they tend to be rich in nutrients that complement breast milk, especially iron. She recommended meat puree in particular."
]
}
|
[] |
[] |
[
[]
] |
||
10brzr
|
Why didn't the French just give Winston Churchill their Navy, instead of forcing his hand to destroy it?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/10brzr/why_didnt_the_french_just_give_winston_churchill/
|
{
"a_id": [
"c6c3o6k",
"c6cjjft"
],
"score": [
12,
2
],
"text": [
"By the terms of the armistice France signed with Germany the French Fleet was supposed to be demiliterized in a French port. Admiral Darlan scattered the French navy to French ports in Africa that were loyal to the Vichy French. The incomplete Jean Bart went to Casablanca, the Richellieu went to Dakar. The main striking force of the French navy was at Mels el Keber in Algeria. Admiral Somerville could not get the local French admiral to comply with his wishes, after six hours of negotiations. The Vichy French government feared reprisals from the Nazi occupiers, if the French just gave their navy to the British. \n \n ",
"Would *you*?\n\n\nThe French government was misled about how long the war would last. In June-July of 1940, they basically assumed that the war would be over in a matter of months. It looked like Nazi Germany was steam rolling over Europe, and it seemed particularly imprudent to go in their way. \n\n\nFurthermore, the French were ticked off at the British for what they saw as the abandonment of French troops at Dunkirk. Franco-British relations were not exactly at their height. \n\n\nTheir point of view: they signed an armistice treaty. How could Britain expect them to break it? After that--Vichy used the deaths of French sailors at Mers El-Kébir in Algeria as some of their best anti-British propaganda *for years*."
]
}
|
[] |
[] |
[
[],
[]
] |
||
1ygmfg
|
what does it mean that the eu is "imposing sanctions" on ukrainian official?
|
What do sanctions do? How will this affect the protests and violence? Will it solve any problems?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/1ygmfg/what_does_it_mean_that_the_eu_is_imposing/
|
{
"a_id": [
"cfkck14"
],
"score": [
2
],
"text": [
"**What do sanctions do?**\n\nThe sanctions are:\n\n* Ukrainian officials are not allowed to enter Europe anymore.\n* Assets of Ukranian officials are frozen at the moment. They can't access their European bank account any more, they can't sell European stock anymore, ...\n\nThe basic message from Europe to the current officials. Fix the issues peacefully if you want be welcome in Europe territory or you want to access your bank account.\n\nYou have to note two things\n* This sanctions are aimed only at officials, and not at the Ukrainian state in general.\n\n* This kind of sanctions are quite fierce. You wouldn't freeze Janoekovytsj assets if you plan to keep him as a friend. I would view this as a bet on a change of regime.\n\n**How will this affect the protests and violence?**\n\nThe protesters will probably not change their behavior. But Ukrainian officials might think twice before they would command to shoot at civilians. (But this is purely hypothetical).\n\n**Will it solve any problems?**\n\nIt would be naive to think that you can solve all the problems so simply. Eventually the Ukrainian people and officials will need to resolve the conflict themselves. But Janoekovytsj could become a bit more tended to concessions during the negotiations."
]
}
|
[] |
[] |
[
[]
] |
|
21j0p6
|
do dogs have a sense of right or wrong?
|
I see a lot of pics on reddit of dogs hiding after destroying something. Do they know what they did was wrong? Why do they do it if they know they will be punished?
|
explainlikeimfive
|
http://www.reddit.com/r/explainlikeimfive/comments/21j0p6/eli5_do_dogs_have_a_sense_of_right_or_wrong/
|
{
"a_id": [
"cgdhtrr"
],
"score": [
3
],
"text": [
"They don't have a sense of guilt like we might sometimes think they do. Rather, they know something they did was bad because they know that will be punished (because it's happened before... same way they know how to sit on command). They do it for the same reason any human misbehaves - they either don't think of the consequences beforehand or they'll willing to accept them (however regretfully)"
]
}
|
[] |
[] |
[
[]
] |
|
3igkl5
|
how can a seemingly small amount of poison or venom be so eefective. 100 mg of venom from a black mamba snake is enough to kill a 100kg adult human. how is this possible?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/3igkl5/eli5_how_can_a_seemingly_small_amount_of_poison/
|
{
"a_id": [
"cug8vr6",
"cug93j2"
],
"score": [
2,
3
],
"text": [
"The biggest reason why black mamba venom is so effective is because, compared to other venom, the molecules in black mamba venom are very light allowing it to spread through the body quickly. Before your body has a chance to react and heal damaged cells there are too many cells being effected and you die.\n\nAlso the toxins are very efficient. One single molecule can destroy a cell. And they can pack a lot of molecules in a single drop.",
"I believe that poison works by interfering with your nerve cells. Many others work this way. If that is the case the molecules bind to the receptors at the very end of nerve cells that they use to communicate with the next one down the line. Nerve cells are long and skinny, so you're disabling a fairly large cell by messing with only a small part of it. Add to this that nerves make up a small amount of your body mass in the first place. You're only dealing with a small amount of poison but it's targeting a *very* small part of your body. \n\nAnd because it sticks to nerve cells, it doesn't need to be highly concentrated in your bloodstream. It will eventually stick to those receptors and build up only in those critical locations, rather than staying spread out through your blood. This is different from alcohol which also effects nerve cells (in a different way) but doesn't stick to them. It remains spread out through your body even though it only effects a small portion of your body. This is why blood alcohol concentration is a good measure of how much is in somebody's system and an OK way of figuring out how drunk they are. Testing for snake venom in the blood doesn't tell you about how much damage has already taken place, or how bad things might get before the effect starts to fade. "
]
}
|
[] |
[] |
[
[],
[]
] |
||
35g6aq
|
How is glass made?
|
I understand that glass is made from sand, but that's about all I know.
|
askscience
|
http://www.reddit.com/r/askscience/comments/35g6aq/how_is_glass_made/
|
{
"a_id": [
"cr49tsu"
],
"score": [
17
],
"text": [
"There are many different compositions of glass. In scientific terms, a glass is a solid that lacks any well-defined crystal structure. \n\nBy far the most common is Soda-lime glass. The raw ingredients for which are silica sand (silicon dioxide, SiO2), sodium oxide, and calcium oxide. Small amounts of many other chemicals may be added to affect the glass's properties. For example, small amounts of cobalt oxide give a beautiful blue stained glass.\n\nSoda lime glass is the type used for windows and mirrors, as well as most household glassware and glass bottles.\n\nAnother common type is borosilicate glass, which is made of silica sand, sodium borate (aka borax) and sodium oxide. This has the unusual property of having near zero thermal expansion. So it can endure repeated heating and cooling without danger of cracking. It's used for laboratory glassware for chemists and biologists for this reason. It was also commonly used for glass baking dishes in the past, but because of it's expense has tended to be replaced with certain types of soda lime glass in recent years. \n\nA third type is lead oxide glass, aka lead crystal. This is made with silica, lead dioxide, potassium oxide (aka potash) and small amounts of soda and zinc oxide. Because of it's high light refractive index and color dispersion it's popular for glass artists and optic lenses. It sparkles like cut gemstones with rainbow patterns, if cut in certain ways. \n\nA fourth type is germanium oxide glass. This is created with ultra high purity silicon dioxide and germanium oxide, this gives it extreme optical clarity. These are used for fiber-optic cables used to carry information. Without this kind of glass the internet simply wouldn't be possible and you wouldn't be asking this question.\n\nA fifth type is aluminosilicate glass, which is a complex mixture of silica, aluminum oxide, calcium oxide, barium oxide, and sodium borate. This is used for high strength fiberglass cloth, for composite materials such as boats, aircraft, bicycle frames, and car body parts. It has an extremely high strength-to-weight ratio. being both stronger and lighter than steel.\n\nOther types exist. Although silica is the base ingredient of the vast majority of glasses, glasses that don't contain silica can be made. For example, glasses made with phosphate compounds. These are useful in LASER systems. Another example are glasses made from heavy metal fluorides. Some metal alloys can even form a glassy non-crystalline structure when they're cooled rapidly in thin ribbons. These are useful for making the magnetic cores of power transformers. "
]
}
|
[] |
[] |
[
[]
] |
|
1klspf
|
When did Bank Heists become a thing?
|
When did Bank Heists become a popular way to get money for criminals? Are there any ancient "bank robbers"? How are actual bank heists different (if they are at all) compared to how they are portrayed in media?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1klspf/when_did_bank_heists_become_a_thing/
|
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"I'll let the experts elaborate but simple answer is \"when banks were invented\" ... \n\nWhile that might an exaggeration, highway-robbery and highwaymen are certainly a very old \"tradition\" and a driving force behind banks - ie not carrying money/valuables around\n\nSeems by 1880's in USA bank robberies were fairly common ... the whole Wild West thing ... with the first verified one in 1866.\n\nEDIT: For example, Bank of Australia was established in 1826 and robbed by 1828 - it was our 2nd bank after Bank of NSW in 1817. So at least one country was fairly quick and I'd imagine most followed."
]
}
|
[] |
[] |
[
[]
] |
|
1n3vwo
|
Do holocaust deniers have any valid points?
|
Obviously the holocaust is pretty much universally thought of as historical fact. So is there anything the deniers say which is at all true? If the evidence is so overwhelming why do they still exist? (I'm guessing stubbornness and anti-semitism) Just came across [this](_URL_0_). The main argument the person has is this:
> 1. No German plans were ever found mentioning any plans to exterminate Jews.
>
> 2. No mass graves were ever found.
>
> 3. No piles of human ashes were ever found.
>
> What proof exists that the Nazis killed six million Jews? None. All we have is postwar testimony, mostly of individual "survivors." This testimony is contradictory, and very few claim to have actually witnessed any "gassing." There are no contemporaneous documents or hard evidence: no mounds of ashes, no crematories capable of disposing of millions of corpses, no "human soap," no lamp shades made of human skin, and no credible demographic statistics.
>
> What evidence exists that six million Jews were not killed by the Nazis? Extensive forensic, demographic, analytical and comparative evidence demonstrates the impossibility of such a figure. The widely repeated "six million" figure is an irresponsible exaggeration.
Not the first time I've come across holocaust denial on the internet. Do this guy, or any other holocaust deniers, actually have any valid points? How easily refuted are they?
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/1n3vwo/do_holocaust_deniers_have_any_valid_points/
|
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"There is a hell of a lot of evidence that it happened. There are photos of the camps, and the graves there are testimonials from all sides involved confirming what happened. The Allies made damn sure everything was recorded and brought up at the Nuremberg trials because it was so horrendous. I really don't know where the deniers get all this from, it isn't hard to find the evidence at all.",
"Every time this subject comes up I link to [this](_URL_0_) thread. But honestly you can sort of read between the cracks of what you posted to see that whomever was claiming that obviously has an agenda.\n\nFor example: \n\n > No German plans were ever found mentioning any plans to exterminate Jews.\n\nSo that book about Jews being the bane of civilization just happened to be written by the guy later blamed for killing Jews? Besides, it's a well known fact among historians that Hitler's commands weren't always given as a signed letter, but manifested by underlings aiming for \"the will of the Fuhrer\"\n\n > No mass graves were ever found, No piles of human ashes were ever found.\n\nThis is just blatantly false.\n\n > All we have is postwar testimony, mostly of individual \"survivors.\" \n\nNotice how a single sentence devalues the extensive archives of personal testimonies given by thousand of survivors (no \"\"s needed). Of course they would be contradictory, you're dealing with people who were under immense pressure or children at the time. This is just the sort of thing you would see in a holocause denial argument - it doesn't matter that there is proof because any valid proof can be dismissed.\n\n > no mounds of ashes, no crematories capable of disposing of millions of corpses\n\nThis is strawmanning. Of course millions of people weren't burnt. Some were shot, others starved, some died from illness, overwork or the forced marches. The six million were not gassed, only some of them, and for them, the existing facilities were more than enough. \n\n\nWe can go on, but the truth is, when people put agenda before facts, no amount of evidence would satisfy them.",
"I believe that Gen. Eisenhower, aghast at what he saw, ordered Army Photographers to document the camps.",
"Not really. Matching reports from survivors, perpetrators, witnesses along with photographs, large amounts of human remains found at the mass murder factories constructed in plain site, etc. People still alive to this day with serial numbers tattooed on them. The list goes on.",
"The only generally valid point they have is that it is a sensitive topic and if you seem too contrary about it you will be tarred and feathered and kicked out of serious discussions before anyone bothers listening to your argument very much. That doesn't mean your argument is correct, it just means that people generally see Holocaust denial as just a form of pseudo-history and racism, and are generally unwilling to engage with it. Whether such things should be engaged with is a topic of some dispute. (I happen to think it generally not worth the time, because the motivations of those demanding engagement are usually pretty obvious.)",
"Regarding your first question: \"Is there anything the deniers say which is at all true?\" - I think there are times when historians who question the classic \"6 million\" Jews killed, and present research that shows perhaps less than 6 million were killed. Historians who question that number are sometime referred to as Holocaust deniers, even though their research might be as sound as studies that illustrate the 6 million. \n\nI guess my point is the term \"Holocaust denier\" isn't always applied to the more extreme cases, but sometimes (I hope less often) given to historians who want to investigate the details and reach different conclusions.",
"I'm not an expert on this, but I can actually explain in terms of historical context why it is that there are no signed documents or orders mentioning plans to exterminate the Jews.\n\nHitler ruled a party system which in turn ruled a country. Very few of the orders that went down through the system can be traced directly to any one person, and it was planned that way on purpose after the public backlash against the T-4 program. Hitler signed a document authorizing the administration of euthanasia for the disabled and those who would be obviously physically or mentally unable to participate in German society. Note, this didn't just include the mentally disabled and the physically handicapped the way we understand it now~~; the DSM-IV was a much more inclusive document back then~~; you could be killed for the \"mental disabilities\" of homosexuality, alcoholism, adultery, or any of a number of things like that.\n\nA prominent Catholic priest did speak out against the T-4 program in the late 30s and there actually was a meaningful public backlash because people feared that under those guidelines it was entirely possible that the list of people who \"don't fit into German society\" could one day be extended to include combat veterans. What group of people, after all, is more likely to be plagued by physical handicaps and mental damages? Thereafter the T-4 program was publicly denounced, but continued in secret, and authorization for it came through indirect, intentionally non-written channels.\n\nThe Holocaust is a separate event, but it's worth noting that many of those who would later participate in the Holocaust were originally employed in the T-4 program. Note, they did a really terrible job of keeping the T-4 program a secret from the general populace, but the point is at the administrative level they did ensure that it left no paper trail. Note also, the area in Poland in which most of the Holocaust actually took place was not in Germany proper; the territory was not incorporated at any point and actions taken there would have formally been under the jurisdiction of the \"General Government\" of occupied Poland, or some branch of the Military or Secret Police.\n\nIf we really want to figure out where the direct orders came from it would be best to peruse the personal correspondence between army officers in Poland and party officials in Berlin. This last part is just speculation, but if anyone has access to that kind of resource that would be interesting to look at.\n\nMain source: A series of lectures from a 20th Century German History class at OSU. I have a book that documents some of this stuff too, I'll look through that too when I get home and see what I can find in that and see if I can't get you some citations that are more specific than \"Some lectures\"\n\nEDIT: It's been pointed out to me that the DSM-IV didn't exist back then. My point had little to do with the DSM-IV and revolved around the fact that \"mental illness\" was not as narrowly defined then, but still; good point, I should use a different figure of speech.\n\nAlso, about those sources. I found two noteworthy sources here after looking around my room;\n\n1) John Toland. \"Adolf Hitler\". 1976. \n\nThis one is a bit dated, and it isn't published by a University Press. But I read it and it was an excellent account that to my knowledge hasn't disagreed with anything I've read or been taught in classes since then, and it is undeniably exhaustively researched. To list all the information regarding the Holocaust in a 1300 page book about Hitler would be a monumental undertaking, but I will throw a few things out there;\n\n\"In a secret conversation on June 19, 1943, the Führer instructed Himmler to proceed with the deportation of Jews to the East 'regardless of any unrest it might cause during the next three or four months.' It must be carried out, he added, 'in an all-embracing way'\" (Adolf Hitler, 1039)\n\n2) Fulbrook, Mary. \"The Divided Nation: A History of Germany, 1918-1990\". Oxford University Press. 1992.\n\nMore recent, this one is also more direct and actually does directly address the fact that there are no orders on paper, stating that regarding the physical extermination of the Jews which began in 1941, \"No written order has been found as yet, and in any case such an order from Hitler would be more likely to have been given orally, making known to associates what was 'The Führer's Wish'.\" (Divided Nation, 109) On the next page, the link between the T-4 camps and the Holocaust is drawn, \"The euthanasia program had been formally terminated in response to public outcry... But the techniques learnt on the euthanasia program of 1939-1941 were transported to the death camps in the east.\" (Divided Nation, 109-110) Later the question of paper trails is revisited, \"At the empirical level, historians by and large agree that the search for a written Hitler order to resolve the issue is probably a waste of time, since it is in any case unlikely - given both Hitler's work habits, and his known desire to camouflage the Final Solution, even linguistically - that such an order would have ever been issued in written form.\" (Divided Nation, 117)\n\n",
"As a side note tot he question - it is not so much a question of historical evidence. If you are going to deny the holocaust, you'd have to throw so much evidence to the side that you'd basically be saying \"no evidence can ever prove any point\". The sheer amount of holocaust evidence would mean that logically speaking, if you deny the holocaust, you could start denying that the Roman Empire didn't exist, that WWII never happened or that the War on Terror is a hoax.",
"From what I've read on some websites I think many Holocaust deniers don't believe that it didn't happen,just that some facts where misinterpreted for the benefit of the Jews. Looking at what the population on Reddit thinks this seems like a valid point. \n_URL_0_ \n\"Of the 11 million people killed during the Holocaust, six million were Polish citizens. Three million were Polish Jews and another three million were Polish Christians. Most of the remaining victims were from other countries including Hungary, Czechoslovakia, Ukraine, Russia, Holland, France and even Germany.\" \nBasically about half of the people killed where not Jewish yet people never talk about it,it isn't in the public consciousness because (some argue) the jews \"in charge\" have manipulated the media for their on benefit. \nI do not know if this is true or verifiable but it sure shows a bias of the population towards certain topics.What is forgotten and what is remembered(an how) seems like under the influence of the people in charge,and it's obvious they have interests displaying a certain narrative. \n",
"This isn't ultimate proof or something that's capable of making holocaust deniers shut up, but whenever this topic comes up I link to this image:\n\n_URL_0_\n\nIt's a bill by the company Degesch for Zyklon B. By law it was demanded that harmful gas like Zyklon B had a warning substance added, a distinctive smell, so that a leak in one of the containers wouldn't kill those handling it.\n\nNow, this bill has a last line, underlined, that reads:\n\n** Vorsicht, ohne Warnstoff! *\n\nWhich translates to: \"Caution! No warning substance!\"\n\nIf Holocaust deniers were right in that Zyklon B was only used to kill lice in the clothes of the KZ inmates, why should they specifically ask for gas without the smell?",
"1: This is false. It's well documented that Hitler rounded up his leadership to reach a \"final solution\" for the Jews.\n\n\n2: This is false. It *is* well documented that a number of mass graves *were* moved though.\n\n\n3: This is also false. In all reality most of the Jews and other minorities who died in the Holocaust weren't necessarily cremated.\n\n\nThe human soap / lampshade thing was well established as allied propaganda a *while* ago. No one's trying to argue that American women who left lights on at home were sleeping with Hitler in secret either. \n\n\n\nIt *sort of* scrapes against the one valid point they have- the death camps as presented in popular media are a *bit* overblown. There were very few purpose built *death* camps in Nazi Germany. Most were labor camps, which happened to run thin for supplies as the war progressed. But you weren't expecting Hollywood to give you an accurate portrayal of any historic events, were you? Live action acting is often a cartoon in itself because they rely on *over* dramatizing events to drive home some *weight* to the events. ",
" > No mass graves were ever found.\nNo piles of human ashes were ever found.\n\n\ni have seen both of these things with my own eyes... ",
"I have a question, my friends grandfather was a child when this occurred. He was a young young boy in France. Not even sure if he was old enough for schooling yet. But he had told my friend that during this time (the occupation of France) the SS would enter schools. Make the young boys pull down their pants. And see if they were circumcised. Now did this occur or is this wrong? My friend didn't say whether or not the SS would do anything like shoot on site or execute the boys. Just that they'd do this.",
"I see a problem. I contend that many answers here are way below the normal standard allowed in /r/askhistorians and while I am by no means a holocaust denier, one can see why getting answers like this may actually fuel the disbelief. Also (not that many of these were particularly emotional) the emotional and dismissive responses - sometimes just personal attacks even - that are common in this subject are never going to satisfy those with questions, whether the questions are honest or not. \n\nI myself am not a holocaust denier but am a skeptic by nature, so I wouldn't be surprised if common perception of the event has some significant inaccuracies (which may be innocuous). When searching for \"what do we know for sure\" you get tons of .org responses, tons of \"people who question it are quacks\" -- answers that do not fully satisfy. I say askhistorians should be the opposite, per the usual outstanding standard of this sub. Many of these high level posts should have been deleted. ",
"As has been stated earlier, most \"deniers\" aren't saying no one died or that concentration camps did not exist, but by claiming that somewhat less than 6,000,000 Jews died or that there was no organized, systematic attempt to exterminate the Jews, I think they show their biases by attempting to pick at secondary facts and ignore the tragedy as a whole. Even a a Jew, I disagree with the term THE Holocaust. There have been so many: The Africans killed while being transported as slaves, Stalin's purges, Mao's various revolutions, Pol Pot's massacre of millions in Cambodia...I could go on and on. All were holocausts, most with more casualties than the Nazi holocaust, but that does not diminish any of them. So I don't understand the attempt of these people to diminish the Nazi holocaust by picking at numbers, motivations or tactics."
]
}
|
[] |
[
"http://www.reddit.com/r/Documentaries/comments/19gw8n/one_third_of_the_holocaust_explains_how_treblinka/c8okyjs"
] |
[
[],
[
"http://www.reddit.com/r/AskHistorians/comments/z9ywa/how_to_deal_with_holocaust_denial/"
],
[],
[],
[],
[],
[],
[],
[
"http://www.jewishvirtuallibrary.org/jsource/Holocaust/NonJewishVictims.html"
],
[
"http://i.imgur.com/N4SBq6W.jpg"
],
[],
[],
[],
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] |
|
96ct12
|
Where were the marines during the Wild West time period?
|
In most U. S. western movies they depict army infantry as the government authority in those times. Were the marines only utilized for amphibious warfare alongside the navy?
|
AskHistorians
|
https://www.reddit.com/r/AskHistorians/comments/96ct12/where_were_the_marines_during_the_wild_west_time/
|
{
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"text": [
"In short, yes, the Marines were utilized for amphibious landings. \n\nIn a bit more length, the Marine Corps was declining. The U.S. Civil War, shortly before the Wild West time period (1865-1895) delegated the Marine Corps to blockade duty. They were poorly, if ever, utilized in battle for the Northern States. \n\nSoon after the Civil War ended, the Navy (upon which the Marine Corps was attached), moved from sail boats to steam powered ships. This left Marines without a duty. Marine marksman were left without a place from which to shoot, as all the masts were replaced with smoke stacks.\n\nMuch of this time was spent in introspection on part of the Marine Brass (higher ups). The traditions of the Corps were defined in this era, and its duties were slightly broadened.\n\nThe Marine Corps had a few chances to use their skills abroad, rather than at home, during those years. First, in response to a native uprising in Taiwan (1867) that killed off the crew of an American ship. The Marines actually lost that one. One Marine died, and zero natives. \n\nThey made up for that loss in Korea (1871) when after a disastrous attempt at diplomatic overtures, Korea fired upon US ships. With no apology coming, the Marines took part in an attack that took over five forts, and left 243 Korean soldiers dead, and only 3 from US forces.\n\nMarines were also involved in the fighting in the Samoan Civil War, though in no great numbers. Their value was proven by the 3 medals of honor earned there. \n\nThere were many smaller landings during that time, Japan, China, Egypt, Panama, Mexico. \n\nBut the only other one of historical note is the coup that overthrew the Queen of Hawaii. The conspirators used the possible danger to American citizens as an excuse to have the Marines sent in. The Marine Corps landed, and patrolled the streets, but were not required to fire any shots, or take over any buildings. Their mere presence was enough to force the royalists in capitulation. \n\nThe Marines wouldn't really come into their \"fighting force\" until the Spanish-American War (1898), at which point the \"Wild West\" had been tamed. \n\nIt may be of note, that in those years, the Marine motto *Semper Fidelis* (Always Faithful) was created, as was the Marine Corps Hymn, and the Eagle, Globe, and Anchor emblem they wear today.\n\nI hope this has answered your question. ",
"Wow thank you for a such an outstanding and well written answer!"
]
}
|
[] |
[] |
[
[],
[]
] |
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65pztk
|
what's the difference between amd and nvidia gpus?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/65pztk/eli5whats_the_difference_between_amd_and_nvidia/
|
{
"a_id": [
"dgcacov"
],
"score": [
9
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"text": [
"Ford and Chrysler both make cars. The cars have four tires, steering wheel and a horn!\n\nBoth Ford and Chrysler vehicles get you from point A to point B.\n\nVideo cards all share a primary goal. Deliver video information to a display port."
]
}
|
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[
[]
] |
||
52olvl
|
why, when we are being put under anesthesia, does it give you a burning sensation up your arm, or from the point in which the anesthesia was administered.
|
Everything the title suggests my friends.
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/52olvl/eli5_why_when_we_are_being_put_under_anesthesia/
|
{
"a_id": [
"d7m0cip"
],
"score": [
2
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"text": [
"If you're talking about getting it through an IV it's actually the cool temperature of the fluid going through your veins. Even lukewarm water can give that sensation since we have such a high body temp"
]
}
|
[] |
[] |
[
[]
] |
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33z5pz
|
For all those b & w photos of construction workers at death-defying heights, how often did we actually lose workers on the job?
|
I always see black and white photos of construction workers perched on steel beams way up in the air during bridge or skyscraper construction. They don't seem to be wearing any safety cables or harnesses.
Just how dangerous was that work? Did we lose a lot of workers that way? And was there compensation for the families
Edit: should have clarified, I mean in the US
|
AskHistorians
|
http://www.reddit.com/r/AskHistorians/comments/33z5pz/for_all_those_bw_photos_of_construction_workers/
|
{
"a_id": [
"cqpshbr",
"cqpvd20"
],
"score": [
10,
12
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"text": [
" > Did *we* lose a lot of workers\n\ncould you confirm: are you asking for info/stats from the USA? thx!",
"Fatalities certainly did occur. During the five years of construction of Hoover Dam for example there were [96 fatalities directly related to construction](_URL_0_). And a good number of these were falls."
]
}
|
[] |
[] |
[
[],
[
"http://www.usbr.gov/lc/hooverdam/History/essays/fatal.html"
]
] |
|
78e5tk
|
how come glass breaks when it hits the ground, but marbles bounce and hardly take damage?
|
explainlikeimfive
|
https://www.reddit.com/r/explainlikeimfive/comments/78e5tk/eli5_how_come_glass_breaks_when_it_hits_the/
|
{
"a_id": [
"dot4wwr",
"dot6hft"
],
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13,
6
],
"text": [
"Spheres.\n\nSpheres distribute the shock of hitting the ground very evenly. A marble can still break, but it's less likely to than a cube, prism, or sheet.\n\n",
"The shape of the marble helps, but it is less significant than the material properties. The manufacturing process of glass marbles creates beneficial compressive residual stresses on the outside of the sphere- this effectively \"prestresses\" the outside. Thus when you drop a marble on the ground, the forces are not enough to overcome the residual stresses, thus never allowing for tensile forces to initiate cracking. This is similar to what you see in tempered glass (the stuff the side windows of a car might be made of, which are harder to break than you might think). \n\n\nThere is a youtube video floating around where a marble is crushed in a hydraulic press - it literally explodes, with all of the internal residual stresses being released instaneuously."
]
}
|
[] |
[] |
[
[],
[]
] |
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