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74fjvh | Why was there so much wealth and excess in the 1920's and 1980's and are we likely to have something similar in the next few decades? | Economics | explainlikeimfive | {
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"Because we look at the past through rose tinted glasses and only remember the good stuff. Growing up poor in the 20s and 80s was just as bad if not worse than it is now. For the 20s you have cases of miners being forced into essentially indentured servitude and then gunned down when the rose up against the situation.",
"The idea that wealth and excess was especially or notably bad in the 20s and 80s is largely thought to be a result of media that supports that idea, things like The Great Gatsby or Wall Street(the movie). However, such extravagant displays of wealth are largely found in the newly rich, while it has been seen the people who grew up with money tend to not be as ostentatious with it. It is thought that such open and glitzy displays of wealth are a desire for the spender to affirm and reinforce his position as someone of wealth in the eyes of others. By that logic, moneyed families know they are wealthy, and know others know they are, so they don't feel as much need of that. As to whether we, as a society are likely to see something similar, I would argue we already have. Look at rappers especially, you hear about them making extravagant purchases, especially in paying for parties. This follows the idea that new money feels compelled to prove their prosperity by making grand displays. For a non musician based example, look no further than Martin Shkreli, pharma bro himself. He paid 2 million dollars for the single copy of the album \"Once upon a Time in Shaolin\"(although to his credit, the sale was initially anonymous). Shkreli made an offer of 10, and later 15 million dollars to get a similar deal with Kanye West's \"The Life of Pablo\".",
"After WW1 factories were retooled to make cheap goods. An abundance of newly tapped oil. Combine that with the casualties from the war causing populations to drop or stay relatively unchanged for a lot of the developed world meant that there was easier access to jobs. Cars and aviation were just starting to shine and technology as a whole just boomed (war is good for this). There is a lot more of course and its worth some in depth study as its all pretty interesting stuff."
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74fpww | If we can't solve the 3-body (n-body) problem, how are we even able to accurately calculate orbits/ paths for space probes like Voyager years in advance? | Physics | explainlikeimfive | {
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"When we say we can not solve the n-body problem we are saying we can not find a nice set of equations that can give a quick and accurate response to where the objects in a system are. However there are other ways to solve a problem. The most commonly used for orbital trajectories is simulation. Given the position, velocity and mass of every objects you can calculate the forces in that exact moment and just assume that the forces are roughly the same for a few more seconds and then you can do the calculations again for the next few seconds. As you do make a few false assumptions your answer will be a bit wrong. However for most cases it is accurate enough and you can just add a bit of safety margin in your mission planning to account for the uncertainty.",
"When people say we \"can't solve\" the 3-body problem, it means that we don't have a closed form solution. We still can approximate it very, very accurately."
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74fy94 | Why does bar soap seem to dry out my skin, but liquid soap doesn't? | I've recently started using bar soap again for the first time in like a decade, and noticed that even while in the shower, it seems to leave a "film" or just a sense of dryness on my skin. But I've never noticed this with liquid soap, or body wash. What is causing this? Are the two types of soaps significantly different? | Chemistry | explainlikeimfive | {
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"Liquid soap isn’t “soap” technically, but actually synthetic detergents dissolved in water. These were invented in the 1950’s when oil was scarce for making soap. While soap and detergent are both technically surfactants, in that they are hydro and lypo philic, soap is usually very alkaline, more so than detergent, and your skin has a slightly acidic oil barrier. When alkaline soap interacts with your acidic oil barrier, it’s very good at breaking it down, removing your skin’s ability to keep water in making it feel dry. Liquid soap most definitely can dry out your skin, but most liquid soap has added humectants like glycerin that help to preserve the acid barrier during cleansing.",
"The bar soap removes the oils from your skin leaving that dry “sticky” feeling. Liquid soaps and body wash tend to give you more oils",
"Liquid soap DOES dry out your skin. Ever washed your face with body wash or liquid soap during the winter? You end up with a dry, flaky face. It may be that your particular liquid contains additional moisturizers."
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74g0as | Why is Urinating in the shower such a common phenomenon? | Biology | explainlikeimfive | {
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"Haha I love that this is tagged biology. It’s probably because all the water goes the same place, ~~pee is sterile,~~ time is short, and you’re not doing anything dangerous or bad by doing so. Edit: my life is a lie.",
"I dont even know why it even is a phenomenon. If you already standing in there naked why not just piss and aim toward the drain? I dont see this as being remotely disgusting. You sit on a toliet seat which multiple asses have touched, but peeing in the shower is such a gross thing?"
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74g0rx | how do airline pilots predict turbulence? | So when I'm flying the pilot often pops the seatbelt button on and advises were gonna have some rough air coming up. How do they know what the air is like before they've flew into it? | Other | explainlikeimfive | {
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"They get reports from other planes in the area, primarily. They also have weather radar that can help them see storms and other disturbances. There are also areas that basically always have it (like coming over the Rockies into Denver)",
"They sometimes gets reports from airplanes ahead of them but mostly it is years of experience. Turbulence can happen in a lot of situations and there are a few things you can look for to recognize patterns that can create turbulence. The easiest and most common form is to look for cumulus clouds. These are clouds formed in a hot day when hot air from the ground rises up in columns. As the air rises the pressure drops which creates condensation and you therefore get a puffy mushroom cloud. These clouds usually have strong turbulence around them as the columns of hot rising air is moving a lot of air around. This type of turbulence is easy to spot as it have a very distinct cloud pattern in it. However there are lots of other types of events that can create turbulence. For example if you are downwind of a mountain range there can be turbulence. If you are closely following another big aircraft there can be turbulence. And lots of other things. Pilots are trained and experienced in recognizing these phenomena and can avoid or prepare themselves for it. Glider pilots are even more familiar with the different types of turbulence as they use them to gain height. A lot of commercial pilots did start out as glider pilots.",
"Air is not stationary. Warm air rises, cool air descends. This causes bodies of air with different temperatures to move. When you're standing on the ground, you experience this as wind. The air is moving along the earth's surface and since you're more or less anchored to that surface, you feel the air move past you. Think of turbulence like this: there are all these bodies of air that have varying temperatures and as a result move in different directions. While you remain in a single column of air, you don't notice much turbulence. Sure the plane might rise a bit if you're in a column of rising air or descend a bit if you're in a column of descending air but the pilot will adjust for it without you realising. But if you move from, say, a column of rising air to a column of descending air, you might get quite a bump. After all, the plane is just trying to move forward and suddenly the surrounding air goes from lifting it up to pushing it down. And if you end up in an area where upwardly and downwardly pockets of air are swirling around each other, you get a pretty bumpy ride. As for how they predict it... since turbulence is caused by columns of air that move in different directions, you look at factors that influence turbulence. For instance, clouds are a good way of visualising air movement. If you see a big fluffy cloud that has towers growing out of it, those towers are cloud vapour rising on warm air currents. Paragliders and sailplane gliders often aim for those hoping to rise higher in the thermals. Ridges in the terrain like hills and mountains can create updrafts where horizontally moving air hits the landscape like a skateboarder going up a ramp. Those often have predictable turbulence. Weather is another good indicator. When warm fronts meet cold fronts the result is predictably a lot of moving air."
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74g43g | Would a fully 1 to 1 life-like virtual reality ever be possible? | Technology | explainlikeimfive | {
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"Hypothetically, yes. Assuming we have no limitations on processing power, it's already quite common for graphics to be realistic enough (just check any trailer for a First Person Shooter to see what I mean). Projecting this in a fully 3d space is hard, but let's stick to the unlimited processing. The next step is AI (to simulate realistic animals and people). This AI doesn't need free will, it just needs to look like it, which can probably be done with enough time. Physical response would also be important for a life-like simulation. You'd probably need a rig that could constantly adjust itself to where ever you are in the simulation, which is probably where a limit is reached. It's just to complicated to create the proper physical touch in as short an amount of time you'd need. However... if you're willing to get some rather invasive surgery, you might be able to get electrodes that would send the signals your brain would receive from touching something artificially. So, to answer the question, if we get powerful enough processors and improve neurology, yes. Just don't expect it tommorow. EDIT: Grammar, Typos, and Clarification"
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74g4rz | How do movies get distributed to theaters? | Other | explainlikeimfive | {
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"Films are shipped on a 3.5\" hard disk drive. Strong encryption is used to ensure playback is only possible on the projector at the destination cinema."
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74g6ay | why do we like 4/4 beats so much | Biology | explainlikeimfive | {
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"If you want to explore different tempos check out Dave Brubeck's 1959 album [Time Out.]( URL_0 ) The best known song is Paul Desmond's [Take Five]( URL_1 ) is written in 5/4. To hold it together Dave Brubeck plays a repeating vamp though out entire song. URL_2",
"\"We\" don't. You just like 4/4 because that's the overwhelming majority of the music you listen to, and so anything else doesn't fit with your musical sensibilities sounds wrong to you, but that doesn't mean it's some all-encompassing thing. 4/4 is used because it's relatively simple and straightforward; thus it's easy to sell to you. Personally, I'm preferential to 7/8 and 7/4.",
"So, obviously there's quite a bit of speculative theory going on here, but let me throw out one approach that I heard at music school and that made sense to me. Beat patterns are usually about 'strong-vs-weak', or 'call-and-respons'. For example, complex meters like 7/8 or 5/4 are usually broken up (for example, into S-w-w-w-S-w-w for 7/8, or S-w-w-S-w for 5/4). Now, 4/4, is actually a simple *fractal* version of this feeling. It can be seen as being two sets (a strong set, followed by a weak set) of two beats (a strong beat, followed by a weak beat). This makes it nicely symmetrical, which we usually associate with stability and comfort (that's why 3/4, 5/4, and 7/8 beats often feel driving, energized, or \"off-kilter\", a little)."
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74g8d0 | Why does moving air feel colder than stationary air, even if I'm not really sweating? | Physics | explainlikeimfive | {
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"Moving air isn't just about sweat and evaporation. It's about heat transfer through the air. You're hotter than the air around you. So you give off body heat and warm up the air around you. Hot air rises, but not very quickly. So you're constantly surrounded by a bubble of warmer air. A fan or wind blows this bubble away, forcing you to feel the actual air temperature rather than your bubble temperature. In technical terms, it changes the situation from [free convection]( URL_0 ) to [forced convection]( URL_1 ).",
"As your body conducts heat into the air, the temperature of that air will increase. However, this also means that less energy will be conducted into the air over time, as heat transfer is a function of the temperature difference between the hot and cold sides of your process. In the case of moving air, you conduct heat into the air, and that air is then carried away from you and replaced with fresh cool air. Thus, the rate of heat transfer into the air stays high for moving air."
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74g9cl | Why do some drivers veer left of right while going over a railroad crossing? | I see this on a regular basis. At least once a month I see someone veer enough that I think they are about to drop a wheel down onto the track. | Other | explainlikeimfive | {
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"It distributes the rebound from the suspension by loading them at different times... so the car docent just hit them square on.",
"i have encountered varying differences in height between rail and road, and my car isn't in great condition, so i usually look for areas of more level crossing height. one rail crossing i used to drive over for work required a full car width veer to the left (so into the other lane almost) but allowed me to drive on road that wasn't worn down by millions of other drivers. basically when the road is built it is all level and smooth (this spot likely was never done too any exacting standard though) but cars wear grooves in the pavement where the tires go. if these grooves lead into rougher road from freeze/thaw damage or a change to another medium (like a concrete patch between tar patches, or a rail crossing with hard angular grooves) you'll usually see drivers try to avoid that to save their car and tires unneeded stress. like going around a puddle in the middle of a well worn foot path by walking on the grass. but your post implies they are purposely driving into the tracks so idk."
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74gfe5 | What prevents video game developers that have digital content get sold by third parties from creating the content themselves and selling it? | Technology | explainlikeimfive | {
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"If you mean officially, why would they conceal it? They could simply sell any skins they wanted through an official store. IF you mean an individual developer, that would be at minimum a breach of their employment contract at at worse a fraud charge."
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74gi8n | Muscle memory and how does it works? | I have been told that some/all muscles "remember" sertain repetitive actions or movements performed for long periods of time. Is it true? How does that mechanism works? | Biology | explainlikeimfive | {
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"It's not the muscle that 'remembers' the action, but actually the neural pathway. Neurons fire in a certain way (swinging a baseball bat for example) when you do an action. The more you do this action, the better/stronger/more used this 'path' becomes so neurons are more likely to fire down this pathway again.",
"It's not your muscles--it's your brain. In a way, it's similar to how memory-memory works. When you study something over and over rehearse it in your brain, changes happen at the cellular level in nerve cells that strengthen the connections between them. These nerve pathways fire more accurately and consistently. When you throw a basketball, your brain has to calculate the position and tension of all the muscles you're using (as well as how relaxed the ones you aren't using are). It has to calculate the appropriate position and velocity of your arms. When to release the ball. How much force to put behind it. etc. There is a complex communication between the frontal lobes of your brain, your cerebellum and your spinal cord which are involved in this process. The more you use it, the better you get at fine-tuning these \"motor programs.\" The same is true whether you're playing a video game, learning to ride a bike or playing a musical instrument."
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74gptz | Why do eggs keep getting rebranded as "good" or "bad" for health | Other | explainlikeimfive | {
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"Media outlets want to grab your attention, so they seize upon very narrowly focused research results that require a great deal of context to interpret, drop the nuance, expand them to common foods, then push headlines about how the common food is now bad/good for you."
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74gq8e | why do your ears ring after loud noise and have been damaged? | Biology | explainlikeimfive | {
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"The cochlea in each of your ears is a spiralling organ that contains a bunch of tiny little \"hairs.\" When sound is transmitted from the air into your cochlea, it travels through the cochlea and depresses hairs corresponding to different frequencies. [The hairs further and further in the spiral]( URL_0 ) correspond to lower-pitched sounds. The hairs right at the entrance correspond to high pitches, and are the most vulnerable as they take the bulk of the \"impact.\" When something super loud hits your cochlea, those hairs are depressed, and they stay that way for a bit. This means that your brain constantly hears a high-pitched ringing noise until the hairs stand back up. When something is loud enough to permanently damage your hearing, those hairs corresponding to high pitches never fully recover and constantly send the signal to your brain that you're hearing a ringing sound. They persist indefinitely in the \"on\" position."
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74h2vc | What is that white stuff on my teeth I scrape off sometimes? | Biology | explainlikeimfive | {
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"Bio film. Bacteria basically create this gooey substance to live in and try to take over the world. They’re comfy there so they can replicate. But when we brush our teeth, were disturbing their colonies and pull them apart. Ideally, you shouldn’t have it on your teeth, it’s a sign of poor oral hygiene."
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74h8xe | How does snoring work? | Also, can i tell if i'm snoring? | Biology | explainlikeimfive | {
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"> Can i tell if i'm snoring? For the most part, no. Even if it suddenly wakes you up, you're unlikely to initially realize that you were woken by the sound of your snoring. > How does snoring work? Snoring is the sound produced when air passes through your pharynx while it's not fully open. In other words the part of your nose/throat that leads to the lungs isn't totally clear, so as air passes through the airway, it's turbulent and causes vibration. It's similar to how a whoopee cushion produces sound as the air passes between two thin layers of rubber and makes them vibrate."
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74hai5 | How is a death ruled by overwork different from a death ruled by sleep psychosis? | Biology | explainlikeimfive | {
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"When you're overworked and die as a result, it's likely because your body has run out of fuel to maintain basic functions. That could be dehydration, low blood sugar, etc. Once you pass out, you're no longer able to meet these needs and can die. You literally can't help yourself, even if your last thought before passing out is that you need food or water. When you haven't slept, your body accumulates adenosine, which has numerous effects on the body. It lowers your heart rate, and dilates your blood vessels, which reduces your blood pressure. Adenosine also accumulates in the brain to toxic effect, which we don't fully understand yet. When you sleep, astrocytes (specialized cells) in your brain degrade the accumulated adenosine. In your typical day, adenosine accumulates in the brain causing \"sleep pressure,\" but never becomes so concentrated that your brain is in danger. There are various studies suggesting the mechanism of sleep deprivation-mediated death, but frankly we haven't nailed it down yet."
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74hf1e | Why do we sometimes skip words without noticing when typing or reading? | Other | explainlikeimfive | {
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"This is a consequence of your brain having a deep understanding of a language and filling in in the gaps, or ignoring things that don't matter. You'll notice in that last sentence, I used a word twice in a row, but your brain may have ignored it. It's similar to how we can finish each other's sentences, because our brain has learned by repetition. When you're not fluent in a language, you're less likely to do this. For example, a novice Spanish speaker is going to notice a missing or duplicated word, because they're still trying to understand sentences word-by-word. Once you're fluent, you're reading/writing for broad comprehension, rather than making sure each word is correct. It's kind of like the tax you pay when you understand a language well enough that it's inconsequential for a word to be duplicated or missing, as it doesn't affect your comprehension."
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74hkd1 | Why can martial arts experts break bricks with their hands, but when a normal person try, he ends up with a fractured hand? | Biology | explainlikeimfive | {
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"There's a few factors at play here: 1. If you practice enough mashing your bones against hard things, your bones get harder. I know a muay thai expert who says his teacher (master, sensei? I forget) trained in the old days by basically striking tree stumps with his shins for an hour a day, to toughen up his bones. You create little fractures, and when they heal, they calcify and become harder. 2. If you break something, the force of your hand/foot/whatever is overcoming the forces holding the object together, which means that you're getting less resistance out of the object. Think of falling onto concrete versus falling onto foam rubber - the foam rubber deforms and absorbs more of the impact, while the concrete pushes back at you as hard as you're pushing on it. So if you strike a brick and don't break it, it's always going to hurt more than if you *do* break it. 3. A lot (but not all!) of the bricks and wooden panels that martial artists use are designed to be broken. If you know what you're doing and where to apply force, you're going to have a better time than someone just swinging and hoping for the best. All that considered though, this stuff is hard. My wife is a karate sensei and even though her style doesn't usually do breaks, she's worked with other styles with more of a focus on that aspect, so I've seen her and people she trains with break boards and bricks, chop through rocks (like flat, river rocks), and I've seen people kick through Louisville sluggers. It definitely still hurts.",
"Few things at play here but 95% of it is technique. If you're talking about a punch then it's also a little bit of conditioning your body to be ready to take a hit. When you punch correctly it's only supposed to be your first and second knuckles that make contact. The other ones will guarantee broken bones, similarly many people put their thumb in their fist, again broken bones. With that the more you practice punching the more your body can adapt and will actually build up calcium deposits on your knuckles to increase their strength. However most experts still don't like punching bricks because it doesn't feel good. Many will do an open hand strike, called a palm heel or something. In doing so they soften the blow to their bones with the palm of their hand but additionally the don't 'hit the board' they 'hit through the board'. What this means is that when a layperson tries to break something they will actually attempt to have their arm fully extended at the point of contact so not only is the brick pushing back but your arm is also fighting you. An expert will aim to fully extend 3 or so inches beyond the board so you have your momentum still building when you reach the board."
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74hqg8 | Whats the difference/distinction between semi-automatic and automatic weaponry and what are/how do Bump Stocks turn Semi-Autos into Automatic weapons? | Technology | explainlikeimfive | {
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"A semi-automatic firearm fires one bullet each time the trigger is pulled. To fire a second shot the trigger has to be released and pulled again. An automatic will keep firing as long as the trigger is pulled and isn't released. Bump Stocks don't turn semi-auto's into auto's they just cause the trigger to be pulled extremely quickly by 'bumping' the weapon forward so the trigger is pushed into the finger which has the same result as if the finger was moved back to pull the trigger. Bump Stocks enable the trigger to be pulled much faster than if the operator actually was actually moving their finger each time."
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74i7un | Why is it necessary for generator engine size to increase as output voltage increases? Is it possible to run a 50Kw generator with a tiny 1000cc engine? | Technology | explainlikeimfive | {
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"Voltage has nothing to do with generator size, power does It is totally possible to run a 50 kW generator off a 1000 cc engine, 50 kW is only 67 HP. It's a very different story if you want a 50 MW generator, that'd be 67,000 HP so you're going to need a really big and powerful engine",
"The generator can only output as much power as the engine outputs -- otherwise you'd be making energy from nothing, which would be magic. One horsepower is just an old-fashioned term for 746 Watts, so if you have a 10 hp engine, that engine can produce up to 7460 Watts of energy, and can never run a generator to produce any more than that amount."
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74idsl | Why do ants insists on showing off their houses above ground, wouldn't a simple hole work? | Biology | explainlikeimfive | {
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"text": [
"The hill isn't there to show off. When the ants dig out hollow spaces underground, the dirt that used to be there has to be moved somewhere else. The easiest thing to do is to pile it right outside the entrance."
],
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74iley | Why is there an entire discipline of chemistry (organic chemistry) surrounding just one element (carbon)? Why is carbon so important, instead of reactive, abundant elements like hydrogen, etc.? | Chemistry | explainlikeimfive | {
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"Carbon is important because it provides much of the structural foundation for life. So, understanding the chemistry of carbon is critical for us to understanding the chemistry of living systems (such as cells). Why is Carbon the main structural atom behind molecules necessary for life? Well, because of its electron configuration, it's really good at bonding to other Carbon molecules in a large variety of ways. This allows a lot of molecular complexity, which life (as we know it) seems to require. Think of it like a universal Lego connector. Organic chemistry isn't just about carbon, though. It's also about the interactions between carbon and other life-critical atoms like hydrogen, oxygen, nitrogen, sulfur, and many others.",
"Synthetic organic and medicinal chemist here. There's a lot of good answers here, but I'll take a stab: 1) Abundance: Carbon is extraordinarily common. As stars fuse atoms the elements get heavier and heavier. Carbon is pretty early in the chain, so hydrogen burning stars get to it pretty quickly. It's before iron on the periodic table, which means most stars can form it easily (i.e., it doesn't require a super nova). 2) Carbon is almost uniquely comfortable sharing electrons with other elements due to a property called electronegativity. It's neither too electron liking (like chlorine) nor is it too electron disliking (like sodium). It is pretty much dead in the middle of the scale (i.e., just right). That means it tends to share electrons in a type of bond called a covalent bond when it can find partners of of the right size (I'm oversimplifying descriptions about orbitals here) 3) Carbon has lots of similarly sized neighbors like oxygen and nitrogen. Also, The similar size makes it relatively easy for to form covalent bonds. Carbon is so accomodating though that it tries to form covalent bonds with almost anything even metals. 4) Carbon in addition for forming stable bonds, carbon forms up to four of these bonds. This allows for a wealth of structures to be formed. Also, unlike silicon (which can also form four bonds), carbon forms preposterously stable double and triple bonds. This leads to even more structural diversity. 5) Despite the stability of it's bonds, carbon atoms can be activated in very specific ways to favor diverse types of chemical reactions (I'd argue that the chemistry of carbon is the most diverse of any element on the periodic table, but that could be due to the fact that we study it more intensively - tough to say). So in a universe where carbon was abundant and capable of forming diverse structures with other common elements that were stable enough to persist, but not too stable so as to enable interesting chemistry, through random combinations of these molecules eventually some of them started to catalyze their own formation. This led to the accumulation of certain types of molecules, which eventually became life. Because it's the building block of most stable biological structures (due to evolution), we build drugs out of carbon because living systems can readily metabolize and excrete carbon based molecules. Because life on Earth has been building carbon-rich biomolecules for 4 billion years we have coal a crude oil reserves which enable the large scale production of plastics and other petrochemicals. tl;dr: Carbon is abundant, forms stable structures that still participate in interesting reactions, and life is based on it.",
"In some ways it is better to think of organic chemistry as biological chemistry. In earth like conditions, carbon forms complex molecules in a way that other elements do not. These compounds are the foundation of life. About 95% of all known compounds contain carbon, usually was their principle atom. That makes it an important field of study in its own right."
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74imvb | How do online games run? | When you install a video game on your PC or Console, the sounds, textures, models, etc. are saved to the hard drive and the game loads them up when you run it. How do flash games and things like that run? Does it need files? | Technology | explainlikeimfive | {
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"Your computer cannot show you anything from the internet without downloading what it wants to show you from it first. Online games run like every other game. The game logic and all accompanying assets such as sounds, models, textures, sprites, whatnot, are downloaded and executed from your computer. Then the computer runs them as part of the website. Some games are smarter than others and only request the files it needs to be downloaded as it needs them. Instead of downloading all 50 levels it only downloads level 1. Then you finish level 1 and it goes off to the website and asks for the files it needs for level 2, and then 3, and so on. Flash games are much, much smaller than the games you normally play via Steam for instance exactly because they are intended to be played online. Flash games are a few mb large at the most. \"normal\" games are on average several hundred Mb, most a few Gb. Having a flash game be a gigabyte large would be a disaster, nobody would be willing to play something that drain their bandwidth and take several minutes to load on a sub optimal connection."
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74ixt9 | siamese twins criminal | Other | explainlikeimfive | {
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"The proper term is \"Conjoined Twin\" and the answer is no one knows. It has never happened and until does happen there is no need to figure out how to rule on it. In all likelihood they would be let go, in the US at least. The 14th Amendment prohibits the punishment of innocent people, while the 5th amendment guarantees the right to due process. If the innocent twin were sent to jail with the guilty one that would be a violation of both amendments. But they cannot just let them go without a trial, so the twin who committed the crime would be tired, and if found guilty they would have to have their sentence commuted. That would satisfy the 5th and 14th amendments. Forcing the twins to undergo a separation surgery would probably violate the prohibition against cruel and unusual punishment.",
"We don't really know. To my knowledge, there hasn't been a reported case of a Siamese twin being convicted of a crime in recent history. However, we can infer something from the things we already know. First, Siamese twins are legally two different people. Second, Punishing one with jail/prison or capital punishment is impossible without punishing the other. Third, punishing somebody if it is proven that they didn't commit a crime is against the most principal elements of the rule of law. Punishing an innocent person is far worse than letting a guilty person go free. So most likely, the twin(s) would go free. And of course, their relationship would probably sour a bit. If however, the twins committed the crime together, we can easily sentence both of them for the joint crime.",
"In almost any real case they could just charge the twin who didn't commit the crime as an accessory. Where it would get interesting is if there were evidence that one twin actively tried to stop the other from committing the crime, but failed to do so. Then you have serious problems. One work around is to treat the matter as a civil, mental health case. Technically since one twin is committing crimes, you can lock them both up, since it \"isn't really punishment\" to hold someone against their will in a hospital."
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74izk7 | How come humans are the only species that have to brush their teeth? | Other | explainlikeimfive | {
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"Other species would probably benefit from brushing their teeth. It's common for pet owners to give their pets \"dental chews\" to clean their teeth. Humans are pretty long-lived. Our teeth are important to our diet (we eat a lot of stuff that requires chewing for optimal digestion). There have been studies about how human life improved when we started brushing our teeth. Brushing our teeth helps remove bacteria and gross buildups. That makes us less susceptible to illness or infection. If our immune system isn't constantly under attack from our mouth, it is more effective at fighting off other assailants. Also, take a look in an animal's mouth. Google primate teeth. The look disgusting. Humans have just recognized the benefits of brushing. Long story short, we're the only species that has developed teeth-brushing, but other animals' teeth would benefit from some scrubbing.",
"For one thing, the modern human diet is high in sugars, which feed the bacteria in your mouth and cause them to damage your teeth more quickly. For another thing, many other animal species do suffer from tooth decay. However, they usually die before the time it becomes a problem. The age of a deer, for example, can be found by looking at the state of their teeth. If a deer is able to stay alive long enough, its teeth will eventually fall out and it will starve.",
"Many species should brush their teeth, although they lack the capacity and tools to do so. Many problems in animals in the wild in older age stem from decaying teeth. Rotten teeth lead to infection which leads to death. Weak and brittle teeth lead to lack of food intake (inability to eat) which can lead to death. Sore teeth can cause aggression due to irritation as well as reduced diet (inability to eat proper foods in proper quantities) which can lead to poor decision making for the species which can lead to death. If you have the opportunity, examine an older dog or cat's mouth that hasn't had the benefit of human dental practices, and you'll see that their teeth decay in nearly identical ways to human tooth decay. Humans can survive without dental care, but at reduced lifespans and quality of life. Conversely, animal dental care can increase life span and improve quality of life. Now, most animals don't value minty fresh breath like humans do, and so the mating benefits are not pronounced, and thus probably not important to species survival.",
"Humans are the only species that has developed agriculture and industrially processed food supply, meaning sugary foods are far easier to obtain for modern humans than any other species at any point in the earth's history. Eating sugary foods leaves behind sugary residue in saliva and on teeth. Bacteria feast on the residue, excreting acidic waste that erodes tooth enamel, creates cavities, and damages gums."
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74j093 | How do certain animals reach sexual maturity based off of their weight rather than their age? | Biology | explainlikeimfive | {
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"Reproduction is a high risk/high reward function for many organisms. It requires extra energy to gestate offspring, which can be hard to come by. If a potential mother does not have the energy reserves (fat) necessary to fully gestate the next generation, she could die in the endeavor. Without knowing what animals you are talking about, I can't be more specific than to say that body size and weight can affect the likelihood of success of a pregnancy and mechanisms that prevent unsuccessful pregnancies are important for survival."
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74j0il | How do people steal identities? | Other | explainlikeimfive | {
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"There are a lot of different kinds of attacks which fall under the umbrella of identity theft, and even more strategies of how to engage in those attacks, so the answer to the question will vary a bit depending on which specifics you want to look at. The simplest is just physically taking your credit card from you by some means, and then going to a store and using that credit card as if it was their own. Obviously that requires them to be able to remove the card from you in some way, which limits the amount of attacks a person could reasonably do. And you will quickly notice the missing card and report it, thus rendering the card worthless in short time. The more prevalent form of this type of attack is to retrieve the information that is stored on your card (account numbers and other such identifiers), and then copy that information on to a blank card. There are a number of (shady) places online and in physical shops where you can purchase blank credit cards, as well as the machines to program those cards with whatever information you choose. Retrieving the information off an individual's card can be done in lots of ways. Sometimes it's through \"skimmers\", which are physical devices that copy the card's information when scanned. You'll hear stories here and there of people placing these over legitimate card terminals (often gas stations or ATMs), since high quality ones can be quite well concealed. Another commonly reported vector is restaurant waitstaff, since patrons hand their card to the server who takes it over to a terminal, and thus can quickly scan the card with a handheld skimmer out of view. Then there are online attacks to retrieve such card information. Ideally, these types of attacks would be mostly harmless, as that information is supposed to be encrypted at all stages. But of course, that encryption doesn't always happen, so it sometimes can be retrieved by nefarious actors. Important to note that these hacks are not as often targeted at online-only merchants, since the physical card contains more information than what you enter in an online form when you buy something. If an attacker steals your credit card number and CVV, that's really only useful for impersonating your card in online transactions, but not at a physical card terminal. Once an identity thief has your card, they may also wish to supplement that card with other corroborating evidence of the identity. Sometimes that is merely a matter of having multiple cards in the same person's name (even if some of the cards just have dummy account numbers, they help to establish the identity if questioned). From there, they can work to forge additional documents supporting the identity. Driver's licenses or other such government ID cards are a major one, and again the equipment to create these can be purchased at many of those same locations where the blank credit cards were retrieved. Usually these identification cards do not care as much about full accuracy in the personal information, since that is rarely checked against. If the picture is of the attacker, the name matches that of the credit card, and the identification card looks and feels mostly legitimate, that is enough for the majority of their use cases. Other types of identity theft are more focused on obtaining your (supposedly) private information that is used as identifiers, and less focused on a credit card that you already have. These types of attacks will look to retrieve your full name, date of birth, Social Security Number, residence history, work history, etc. Basically any piece of information that might be asked when you're filling out any sort of financial application. Once they have all of that information, a lot can be done with it. The ways to retrieve such information are extremely varied, but of course the easy one at the moment is just login to Equifax with the password of \"admin\" and download it all. When dedicated to a single target, it is actually incredibly easy to gather all of that information. Social media profiles will fill in a lot of it; cracking a password or two can often get in to various accounts that show partially masked versions of that information from which the full information can be deduced; and placing phone calls to various accounts you own pretending to be you can easily get you \"hints\" from the operator. But individual attacks are less common, as they can be time intensive. More often it is collecting a wide swath of public information, and combining it with smaller pieces of hacked information, to easily align large amounts of information to a variety of individuals. And, as is also the case with the credit card information above, such information can be purchased wholesale online at a variety of dark or deep web sites, where someone else has done all the work of collecting and organizing the information. In fact, many attackers operate solely on one side or the other of this equation, so the individual who performs the hacking is often just selling that information off to others who will go out and use it, rather than taking the added risk of attempting to use that identity information themselves. Once an attacker has all of that personal information, there are a number of ways to use it. One of the more recent attack vectors is fraudulent tax filings. Attackers know that most people don't file their tax returns early, so simply filling it out and sending it in before you, but with a different return address, will have your refund sent to them instead of to you. They may also put in fake income or deduction numbers so that \"your\" return is higher than what you should be getting, making it even more of a pain to deal with. Other attacks would be filing for completely new credit accounts that you are unaware of. These would then be legitimate credit cards as far as any of the banks or processors know, making them easier to pass off for fraudulent purchases (and of course, the attacker doesn't make payments on that account, so the balance just gets maxed out and then passed over to you). At the very extreme of identity theft would be fully impersonating another individual for all of an attacker's public dealings. This would start as above by collecting all personal information about an individual, and then receiving legitimate documentation of the identity from all necessary sources. Things like requesting a copy of a birth certificate, going to the DMV and getting an official license, receiving a passport, even working a job under that assumed name, reporting taxes and opening bank accounts and all of that. Usually, this kind of identity theft would not be a \"turn and burn\", as the attacker would use this identity long term, and attempt to not draw unwanted attention to that identity. This type of attack is mostly for individuals who are attempting to hide their own identity as a primary goal, rather than just profiting off of another's identity as with most of the above. For some more reading, check out Kevin Poulsen's book \"Kingpin\" about hacker Max Butler, or \"Ghost in the Wires\" by Kevin Mitnick."
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74j3uu | What is drawing unemployment? Do you have to pay it back? | Economics | explainlikeimfive | {
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"The laws/rules vary from place to place, but generally, no, you don't have to pay unemployment back. The money comes from taxes or insurance rates paid by your employer. In most places, you become eligible for unemployment after getting terminated or laid off without fault. For example, you'd be eligible if you got laid off due to budgetary reasons, and you wouldn't be eligible if you got fired because you harassed another employee. You're also not eligible if you quit your job voluntarily. Usually, the amount you receive per month as unemployment is related to how much you made at your job, and you're usually required to show that you're actively looking for work to stay eligible. All of this is dependent on what the rules are where you live though."
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74j45m | Some diseases show symptoms at the point of contact, (like Herpes) but why do others show most prominently in one spot? For example, why does Strep Throat affect the throat most obviously when certainly it is not the part of the body that first has contact with Streptococcal? | Edit: Why do diseases "prefer" these areas? | Biology | explainlikeimfive | {
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"Certain diseases prefer to infect particular places, specifically particular *cells*. In oral herpes, for example, the virus infects the cells of a nerve in your cheek. Cold viruses like to infect your nose and throat cells. Strep throat likes to infect throat cells."
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74j4c0 | how do mathematicians know pi is irrational? | The main answer I'm looking for is how they know it doesn't repeat itself. If it goes on and on forever, how can we know that at some point it doesn't just sneakily start over? | Mathematics | explainlikeimfive | {
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"There are ways to prove a number is irrational. For example, [here's]( URL_1 ) a pretty simple proof that the square root of 2 is irrational. Unfortunately, the proof that pi is irrational is probably way to complicated to ELI5. It wasn't proven until the 1700s, which is testament to how complex it is. [Here's]( URL_0 ) a list of proofs. If a number is irrational, that means its decimal expansion never falls into a recursive pattern.",
"Because we know it because it can't be a rational number. (warning, math ahead) A rational number is one that can be represented as a ratio of two integers. For any repeating or terminating decimal out there, you can do a little math to express it as a ratio. With a terminating decimal, it is pretty easy: 0.123 = 123/1000 Repeating decimals require a little algebra: n = 0.123123... 1000n = 123.123123... 1000n - n = 999n = 123 n = 123/999 = 41/333 What does this have to do with pi? It means that either a) pi can be expressed as a ratio of two integers, or b) pi cannot be represented as a terminating or repeating decimal. If we can show there is no way to express pi as a ratio, the only remaining possibility is a nonrepeating decimal. In 1761, this is exactly what Johann Heinrich Lambert did. Unfortunately, his proof, and others like it, require advanced math we'd rather not get into. Lucky for us, the proof that √2 is irrational is pretty straight forward and demonstrates how one might go about this kind fo proof: assume a and b exist, such that a/b = √2, and a and b have no common factors a^2 / b^2 = 2 a^2 = 2 * b^2 therefore a is even, and there exists a k such that a = 2k (2 * k)^2 = 2 * b^2 4 * k^2 = 2 * b^2 2 * k^2 = b^2 therefore b is also even However, we assumed a and b had no common factors, so they cannot both be even. This contradicts our original assumption, which proves it must be false. There are no such number a and b, which means √2 cannot be represented as a repeating decimal, and must be irrational.",
"[Here]( URL_1 ) is a simple proof that pi is irrational. All it requires is basic calculus. The idea is as follows: Assume that pi=A/B is a rational number. Then we can construct a function of the form f(x) = x^(n) (A-Bx)^(n)/n!, where n is any positive integer. To get a feel for what a function like this looks like, see [this]( URL_0 ), where it is done for 22/7, rather than pi, and n=3. In particular, it will pass through x=0, make a bump and then come back down to pass through the x-axis at x=A/B. So if pi=A/B, then this will make a bump between x=0 and x=pi. Another function that does this is sin(x). It passes through x=0 and then makes a bump before passing through x=pi. So if we make the function f(x)sin(x), then it will do this too. The interesting thing about f(x)sin(x) is that the area under the graph from x=0 to x=pi (so under the bump) will always be an integer. Intuitively, this is pretty believable because the area under sin(x) from x=0 to x=pi is 2, and f(x) is a polynomial with nice, rational coefficients which interact nicely (this is explicitly found by applying the Fundamental Theorem of Calculus to evaluate the integral). So we have a function, f(x)sin(x), whose are under its graph between x=0 and x=pi is an integer. But this function passes through the x-axis at x=0 and x=pi and hits its maximum value at x=pi/2, in the middle. Here sin(pi/2)=1 and f(pi/2) = pi^(n)(A-B(A/2B))^(n)/n! = pi^(n)A^(n)/2^(n)n!. This means that the total area under the curve is *less* than pi^(n+1)A^(n)/2^(n)n!. The interesting thing about factorials is that they are, generally, bigger than exponents. This means that, regardless of what A is, we can always choose n to be large enough so that pi^(n+1)A^(n)/2^(n) < n!. But then the area, which is a positive integer, is less than pi^(n+1)A^(n)/2^(n)n! which is less than 1. There are no positive integers less than 1, so we must not be able to make the function f(x), which means that pi cannot be rational."
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74j5jc | using soap too many times a day is bad for our skin? | Chemistry | explainlikeimfive | {
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"Yes, it is. Soap is effective for removing dirt and excess oil, but that oil is also important for keeping your skin moist and hydrated, *plus* it's a protective barrier from bacteria. We use soap so we're not dirty, smelly, and greasy, but your skin still needs some oil to function properly. Most noticeably you're gonna see your skin getting red/dry/flaky with excess soap usage, but it'll also start to exacerbate acne if it's something you already deal with.",
"You already got most of the answer in this thread, but I would like to add on that most people actually don't wash there hands thoroughly enough or effectively enough to be 'cleansing'. I started my study for laboratory science a few years ago and one of the first things we did in Biology was smear our unwashed finger, washed with soap finger and washed with alcohol finger on some bacteria breeding nutrient medium (we call it agar, not sure if that directly translates to English). And basically what we saw with most of the class is that except for obviously the alcohol (which was completely clean), surprisingly the washed with soap part was filled with bacteria. Basically what happens is when you don't wash 'thoroughly' enough, you only 'open the gates' so to speak for the bacteria on your hand. You essentially wash away the barrier but you don't wash away the bacteria. So you will just release a lot of bacteria at once. I thought you might find this interesting and it is kind of on topic, washing your hands isn't necessarily helping you rid of bacteria unless you really wash them well."
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74j7he | why does getting soap up your pee hole feel like Satan himself is setting your Johnson on fire? | Other | explainlikeimfive | {
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"Stuff like your eyes and urethra are kept fairly acidic in order to keep them as sterile as possible. Soap is significantly more basic, so there's a painful reaction when it comes in contact with these surfaces."
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74j8yc | Why do we need peristalsis in the oesophagus when we have gravity? | Biology | explainlikeimfive | {
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"The esophagus isn't a giant, dilated tube that stuff just falls down directly into the stomach due to gravity. It's actually pretty narrow and elastic, so peristalsis helps us push down large volumes of solids, especially closer to the stomach where swallowing isn't helping much. That said, we don't need peristalsis in the esophagus as direly as our four-legged friends. Dogs or other quadrupeds who suffer from esophageal damage/scarring don't fare nearly as well as humans do. They can actually die without peristalsis pushing solids into their stomach.",
"Try this: Stuff some mashed potato into the end of a plastic tube and hold it up and try to let gravity do the work. When it just stays there as just this lump of mashed potato stuck at the top of the tube you'll have your answer."
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74j90i | Why are there ‘name-brand’ pharmaceutical drugs if doctors and pharmacies prescribe and provide mostly,if not always, generics for those same drugs? | For example Norco vs acetaminophen/hydrocodone. | Economics | explainlikeimfive | {
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"The inventor of a drug has exclusive rights to it for 20 years from when the patent is filed. Much of that will be part of the FDA approval process, so effectively they get to sell the drug exclusively for 10-15 years. Only after that do we see generics. By then, the name brand is well known, so doctors and patients will continue to refer to it as Viagra rather than sildenafil. Also, some doctors and patients trust the brand name manufacturer more than the generics and stick with them."
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74jbq9 | Why is it so difficult to stop spam phone calls? | Technology | explainlikeimfive | {
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"text": [
"Because (mostly) they come from countries where they don't have to follow your laws. So they don't, and there's nothing you can do about it."
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74jc4i | Why is it that the more we can't get something, the more we want it? | Biology | explainlikeimfive | {
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"text": [
"This is a case of *confirmation bias* meaning you only notice the cases that fit your theory. Here are some things I can't get and don't want at all: - A rock from 10 miles below Kansas City - An original set of lyrics to all the McDonalds jingles - Ice cream made from lobster liver - A photo of me with your great grand grandfather",
"When you \"get something\" that you want, your brain releases dopamine, which makes you feel good. If it's harder or takes longer to \"get something,\" the potential dopamine release is much greater, and you want it more. This is a super simplified explanation, but it's probably good enough."
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74jn42 | Why do eyes get blood shot? | Biology | explainlikeimfive | {
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"Your body likes to keep the surface of your eyeballs as sterile and free of bacteria/debris as possible. When something irritates your eye, or your eye is infected, the body responds by dilating the blood vessels in your eye to increase blood flow and improve the immune response at the surface of the eye. The response is similar to how you might get redness around a cut on your hand, except that we can see the blood vessels in the eye really clearly because they're not covered by skin."
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74jw3i | How/Why does yawning affect our ears? | Biology | explainlikeimfive | {
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"Your eustachian (pharyngotympanic) tube connects your inner ear to the corners in the upper part of the back of your throat. Its purpose is primarily to drain the contents of your inner ear. When you yawn really big, you fully expose the exit of that tube to the outside world, which lets the pressure of your inner ear equalize with the air around you."
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74k1x3 | If US Supreme Court Justices are suppose to be impartial, why are their personal beliefs and politics talked about so much before being appointed? | Other | explainlikeimfive | {
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"Because the interpretation of laws is not a completely impartial exercise that is undertaken by robots. People can disagree on what complicated words, sometimes written hundreds of years ago, mean, regardless of politics. For example: The 14th amendment guarantees equal protection under the law to all people, regardless of race. The University of Texas creates a policy that gives a slight preference in admission to minority students, in order to rectify past disadvantages (e.g. slavery, Jim Crow) that have influenced these students to this day. They claim that this furthers the goal of equal protection. A white student sues because she was not admitted to the university, despite being more qualified on paper than some students who were admitted. She claims that SHE was denied equal protection under the law. An impartial judge is one who has no allegiance to any party in the case. They didn't work for the University of Texas, and the white student is not their niece. They are called upon to decide whose interpretation of \"equal protection\" is correct, and as we all know, reasonable people can and do believe in very different ways on this issue. So Senators, who are in charge of confirming Justices, ask questions to try to figure out which way the nominee feels on an issue like this. They aren't biased or unfair, they just feel a different way about a law that is open to interpretation. Obviously, Senators would like to confirm someone who views these problems the same way they do, so they ask these questions.",
"There are 3 major historical drivers for it: 1) Roe v Wade - it was such a controversial decision in terms of left/right split, so politicians on both sides decided they needed judges that would fight for it (on the left) or fight to repeal it (on the right). As time has gone on it has become a litmus test for all SCOTUS judges 2)The Robert Bork Nomination - Bork was nominated by Reagan, and was both extremely qualified and extremely Conservative. He was outspoken about wanting to repeal Roe v Wade, and that galvanized the Democratic controlled Senate. The Senate Judiciary committee ultimately voted down his nomination, which was the first time in American history a SCOTUS nominee was rejected on purely ideological grounds. Since then, Republican nominated judges usually evade questions on Roe. Ultimately Reagan nominated Kennedy for the seat, who was more moderate. 3) The David Souter nomination - Souter was nominated by Bush Sr to be another conservative anchor to the court. In the end, he turned out to be one of the most liberal judges on the court, and helped maintain the 4-4+kennedy balance that remains to this day. Since then, Republicans have put a lot more effort into vetting judges for ideological purity, with groups like the Federalist society leading the charge. You could put Merrick Garland in here too, but the failure of his nomination is really an extension of the door opened by Bork and not a new development in itself.",
"There are two views on Supreme Court law, which are the personal views of the Justices themselves. Think of the two sides as a sliding scale, much like liberal mindset and conservative mindset. Strict Constitutionalist < -------- > Living Document Constitutionalist The Strict Constitutionalist law side believes that the United States Constitution is a document set in stone and the only interpretation of the document is exactly how it is written by the Founding Fathers. The Living Document Constitutionalist believes that the United States Constitution is a document that is meant to be interpreted as the spirit of the document to laws that the Founding Fathers could not foresee. The conservative and liberal factions of both the Democrats and Republicans fight over the sides of Constitutional law and the interpretation of the document. TL;DR - Justices are impartial, but interpret Constitutional law differently.",
"The simplest answer to your question is that cases that reach the Supreme Court are cases which either have conflicting laws or no applicable laws that govern the decisions of the court. Often, Supreme Court Justices are drawing from not only the law, but also their personal experiences to help decide what exactly is the best way to handle this and future cases of this type. While judges generally try to see the case objectively, it is impossible for anyone to truly be unbiased, so every judge's affiliations, political or not, can affect their decision, whether they know it or not.",
"The impartial part is not that they are robots. They have their biases and personal view of how a law should be interpreted. The impartiality is based on the fact that once they are appointed, they are on the bench for life or until they choose to retire. That means they do not have to campaign every 4 or 6 years like congressmen or presidents. Essentially, they owe no favors to anyone or any lobbies. They don’t have to worry about earning political points or pandering to public sentiments to keep their job. It is that lack of leverage that makes the impartial relative to other public servants. Congress grills them on political and legal views to understand how they will rule and interpret the law. Remember, once appointed, there is no going back, so you really want to vet them first.",
"There's no clear language that guarantees things like abortion rights (Roe v. Wade). Neither abortion nor privacy appear in the constitution. For 150 years it didn't say that. Then one day it did. The future of it will rest on how \"nine old men\" (now three women) interpret it. If *everything* had to be spelled out, the Constitution would be thousands of pages long. Instead it is written as broad rights (no cruel and unusual punishment) that are left to the court's interpretation. Someday the death penalty might meet that test.",
"Many people have pointed out that “judges aren’t robots,” but most people already get that. What they really seem to have trouble wrapping their heads around is, the law itself is not computer code that specifies with unquestionable precision how individuals and the state ought to behave in every situation. Lawmakers try with varying efficacy to build comprehensive laws, but invariably circumstances arise that no one foresaw any given law applying to. Judges must then try to sort out the resulting confusion when attorneys, each legally and ethically bound to present interpretations of law and fact that best represent their respective clients’ interests, differ on how the law applies to the case at hand. To its very best practitioners, law is a game of language. If you’ve seen *The Matrix* (and it makes me feel ancient that many younger folks these days haven’t) where the characters can get meaning out of staring at a random waterfall of green text, that always struck me as what the best legal minds are like. They just see it all differently from the rest of us, and it can change the way people think. It’s one of the reasons we have juries made up of laypeople. They’re there because they *don’t* have facility with this game of law, but can answer the question “but is this justice” on an “I know it when I see it” basis. On the other end, extreme skill at the game of law is how you get an Antonin Scalia, who was one of the most brilliant jurists to ever sit on the Court, but on the other hand was *so* good he could use his skill to easily and effectively defend positions many people thought were also consistent with being an absolutely horrible person who used the court to advance his own religious and political biases.",
"Impartiality means the \"absence of bias or prejudice in favor of, or against, particular parties or classes of parties, as well as maintenance of an open mind in considering issues that may come before a judge.\" ABA MODEL CODE OF JUDICIAL CONDUCT at 4 (definition of \"impartial\"). However, having an open mind doesn't deny the fact that \"each judge comes to the bench with a unique background and personal philosophy.\" Id. at Rule 2.2, comment 2. Knowing the \"unique background and personal philosophy\" of a judge gives you a good sense of how they are likely to rule, but that doesn't exclude the judge from having an \"open mind.\"",
"The law isn't black and white, nor can every conceivable situation be codified in such a way that there's a clear right and wrong. A computer would interpret the law as Javer did when Jean Valjean stole bread to feed his family - black and white. A computer can't factor things like extenuating circumstances or the application of justice as it relates to the facts of a case. A human being, however, can process and apply nuance and render judgement where the laws and statutes applicable to a situation aren't 100% clear. It's the difference between stealing a truck and stealing a truck to get people to the hospital after the Vegas shooting. Yes, ex marine Taylor Winston stole a truck. But he stole it to save lives. A computer would sentence him for grand theft auto. A human, however, is able to understand WHY he stole a truck and opt to not impose sentence. Justice is the variable... justice is human, whereas application of the law as written is not.",
"\"Supposed\" is the operative word. Justices, like every other human, do not operate in a vacuum of complete impartiality. Therefore their personal beliefs and opinions are germane to how they are likely to rule once confirmed to the court.",
"People have biases and agendas. If they didn't all rulings would be 9-0 (although it would be the same thing if they all had the same biases). There are judges that don't care about the constitution as they have demonstrated in recent history. Example: forcing American people to buy a product or get taxed, is about as unconstitutional as it gets.",
"You've misunderstood the situation. Their personal beliefs and political stances are not discussed. Generally speaking, these things are not widely known. What is discussed is how they have ruled on past cases, and those cases are what people extrapolate out to guess what they think a judge's personal beliefs and political viewpoints are based on how they've ruled. This is an important distinction because every case is different and judges explain their reasoning in their written judgments. So it's never as simple as a judge believing X is good or bad, because you would then expect the judge to rule a certain way on issue X in the future, but in reality the details of each case differ and the legal implications can differ. It's why a judge can surprise you and rule against what you thought he was for (or vice versa)... if you had this simplistic incorrect view of how judges decide cases within the law.",
"Firstly, it's naive to think they won't be impartial. Obviously they should be, but this isn't a fantastical utopia. Therefore, since they're appointed for life, it's important to know what views they have, and thus, try to predict how they will change our laws. edit: More to the spirit of OP's post, politicizing justice is unforgivable, and the sign of an unjust society.",
"“ELI5: If US Supreme Court Justices are suppose to be impartial, why are their personal beliefs and politics talked about so much before being appointed?” Perhaps the question should be: If humans were capable of being impartial, wouldn’t one such judge be enough? Or to put it another way. The chances of a human judge being thoroughly trustworthy and reliable is slim to none. And slim is out of town.",
"None of the answers here really get to the heart of the matter. It's not so much that justices are not \"impartial\" or that they decide things based on political views; it's that there are different and legitimate perspectives on legal and political issues that inform their interpretation of \"the law.\" One justice may view \"the law\" as simply the literal words out down on paper by the legislature. Another may view \"the law\" as a combination of what the legislature wrote plus the known purpose or intent of the law. These are legitimate views that when applied to a certain case might make it come out differently. The issue is that the Supreme Court hears cases that are are hard- that's why they get there. Sometimes they rule 9-0 and are all in agreement. Sometimes it's 5-4.",
"Let's put it this way...if you believed abortion was murder, and wanted it illegal, what would you do? Vote for an anti-abortion governor? Maybe an anti-abortion city councilman? Maybe an anti-abortion US Senator? Roe vs. Wade removed \"voting on abortion\" from the democratic process. It's now a constitutionally protected right, and lawmakers can't infringe upon that right. Ever wonder why the right is so riled up about abortion? It's because they are powerless. Imagine your most important political issue...marriage equality, woman's rights, or gun control...and imagine there being nothing you could do politically to change the situation. And it's been that way since the 70's. There are two exceptions to this. A constitutional amendment where 2/3rds of the legislature change the constitution (never going to happen), or a Supreme Court reversal. That's why the Supreme Court hearing are *SO INTENSELY* political. They are literally the only forum in America to discuss certain political issues."
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74k60w | Why does it seem like pediatricians (and well, all general practitioners, really) rarely get sick, even though they're constantly exposed to lots of messy and contagious illnesses? | Biology | explainlikeimfive | {
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"Two possible reasons: 1. You likely do not see your pediatrician on a regular basis (meaning weekly or monthly) to see her when she does get sick. So it could be that you don’t see it happening. 2. Doctors are trained on hygiene as part of being incredibly cautious with their patients. They do not want to give a disease from a patient at 8:00 AM to the next patient at 8:30 AM. They’ll constantly wash their hands, use gloves, wear surgical masks if examining a patient with a cough or similar disease, etc.",
"* being exposed to a lot of diseases help built up a general immunity * doctors are typically good at disease preventing hygiene * if you are a doctor and get sick all the time, that might lead you to take a career path that doesn't expose you a lot of infectious diseases...research, neurology, or orthopedics rather say, dermatology * you see a doctor infrequently enough it is unlikely you'd notice if they got sick sometimes...if your doctor was sick two weeks out of the year, that's only a 4% of your appointment being canceled",
"They get sick about as often as everyone else. Although they are exposed to a lot of sick people, most of the things they treat aren't infectious and they know to take precautions if they see one. Their workplaces are also generally more aware of hygiene to reduce risk to the doctors, other staff and other patients, especially in hospitals. You're probably more at risk if you work as a teacher than as a doctor. Schools are dirty, and children are filthy creatures!"
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74kfp8 | why can modern wall adapters be plugged in either way? | most wall outlet plugs only fit one way here in the US due to one being wider than the other, however all of my USB to wall adapters are reversible. when did this happen and how does it work? | Technology | explainlikeimfive | {
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"UL rules are if you can prove neither prong can accidently electrify anything outside the charger you don't need a polarized plug (a plug that fits one way). Generally that would be devices with an entirely plastic case (so a lose wire can't electrify anything) and full isolation between the wall and the power (basically, prove that the USB side isn't connected to either of the prongs with a conductive path). If you can't do that, you need polarized plugs (which are used because only the \"hot\" wire is suppose to have voltage, so the neutral should be safe to touch), a polarized plug makes sure it's in the right direction. Practically everything is designed to not need a polarized plug because it's safer. Things that need a polarized plugs (like stuff with a metal case, or an air conditioner, etc) generally require a three prong plug (because neutral is only suppose to be safe to touch, ground actually is considered safe to touch, and ground is suppose to be connected to things you touch)"
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74kkkl | How do we get vitamins from the sun? | Biology | explainlikeimfive | {
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"Vitamin D you get in food is in an inactive form. Gets eaten, circulates around blood vessels including those on your skin. The sunshine's UV rays makes it change to another form, which then goes to the liver, gets changed to another form, finally in the kidneys to the active form that works doing things like getting calcium and phosphate absorption ."
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74kow5 | DNA test results | I just had a DNA test performed that showed some of the different areas that my ancestors have come from. What I don't understand is that I have a 100% match for Europe; some English, German, Iberian, Irish, Scandinavian and so forth but my Dad is a mixed race Papua New Guinean, like 50%, and I have no Melanesian ethnicity showing. Can someone please help explain? | Biology | explainlikeimfive | {
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"I would take the tests with a grain of salt. From what i know, these tests look for specific patterns of DNA that could point to ethnicity, definitely not always accurate. I think it would be interesting to take another DNA test from a different company and see how they compare.",
"A test like this can't *determine* your ancestry. What the test does is look for markers in the DNA that are more common in some populations than others, and these are clues. If you have a lot of \"European markers\", it's *likely* your ancestry is European. But because no markers are *exclusive* to a large population, you can't rule out other options. Take your father as an example: being his child doesn't mean you'll have 25% Melanesian markers. (The markers tested for are not necessarily related to outward appearance.) By chance, you might have inherited only European markers and no Melanesian ones. If you actually had the DNA of your presumed ancestors on both sides, such as your parents, you could see if your own genes are consistent with being their descendant. Obviously you can't do that with a whole population, so there's always some uncertainty."
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74ktkw | If you need the highest level of security clearance to access one compartment of information who sorts the information into compartments? | If there is a reason to let people only know information in one compartment someone has to be above that level of access to make that decision | Other | explainlikeimfive | {
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"The people who gather/create the data send to their supervisor, and the supervisor sends it on to whoever needs to see it from there. This prevents the consolidation of varying forms of information, while simultaneously keeping that information out of the eyes of people who aren't authorized to view it. It isn't about access or being superior in clearance, it's about keeping the chains of information very short.",
"The other thing is, classified information is handled strictly on a need-to-know basis. Regardless of your security clearance, if you don't absolutely have an immediate and pressing need to know that information in order to do your job, you don't get to know it. When I was in the Navy, I had a secret clearance for my job (not a big deal--roughly a third of the fleet has a secret or higher clearance). Despite having that clearance, any secret info not directly related to my job was off-limits to me.",
"Organizations have classification guides that outlines what classification a piece of information should be and has a classifying authority to make formal decisions about classification."
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74kvwg | Why do we need to use polygons in video games? What causes us to need flat polygons rather than simply having rounded shapes? | Mathematics | explainlikeimfive | {
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"EDIT: For the actual 5 year olds, feel free to ignore anything written between the (parenthesis) - this is extra stuff for people to Google-search for if interested. --- I program 3D graphics engines. To calculate a triangle, you just need 3 points and then you fill the space between them. This simple nature allows for some optimisation; we know that only the pixels between these 3 points will be modified when rastered. We can use this knowledge to simplify how the triangle is shaded, so simple texture mapping is just a case of interpolating texture co-ordinates between these points (keeping depth in mind for perspective correctness). There's more optimisations to be had here that will take a lot of explaining (our GPUs have evolved to be very good at dealing with space between 3 points). To calculate a rounded surface, you need an equation for the 3D curve, as well as the limits of the surface. Interpolating texture co-ordinates here would involve re-using that equation over and over again, quite the expensive operation. That equation may also \"push\" the pixels of the surface out into unexpected directions, so optimisations related to the flatness of a simple triangle are going to be much more difficult (they'd need the 3D curve equation to be used again - clipping would definitely be more complex). As a result, early graphics hardware evolved to be very efficient with triangles and all the research and development has been spent there, resulting in real-time graphics to be as amazing as it is right now in its current state. To go back and make a new way of rendering would involve a new class of graphics acceleration hardware that doesn't have all the years of development of the triangle-based hardware we have, that's not a good trade-off. The graphics hardware we have now is also great at sending additional information along with the XYZ positions of a triangle vertex, so we can send texture UV, XYZ normal, reflectivity, roughness, and more as additional numbers tied to triangle vertices and these get interpolated between the triangle points too, very handy. As GPUs get more and more generalised as compute-oriented machines, rather than triangle-rastering-oriented machines, we may see new types of rendering (real-time ray-tracing is possible now, as is voxel based rendering) but these almost always will be slower than using current hardware to render a triangle, so we see these techniques getting used in parallel to triangle-based rendering to achieve effects that aren't as efficient with a triangle-based world (voxels are fast for real-time global illumination, ray-marching [limited ray-tracing] is faster for limited reflections in scenes limited by the amount of triangles displayed). Perhaps one day we'll gain a \"curve\" shader where we can use a curve equation to do a perfectly smooth surface between the points of a triangle (I expect the nature of current raster hardware will allow for some cheats here, interpolating between fragments come to mind), but for the time being that's slower than just having lots of triangles to better estimate the curve with current hardware.",
"There are methods for making \"true\" round volumes and geometry objects in 3D software. Its called Parametric modelling (or it's cousin NURBS) and it's often used by drafters, engineers and architects because it's great at dimensions, simulations and converting models into coordinates machines can use to make real world objects. However parametrics have no way to be distorted or textured. At least, not in software meant to run real-time like in video games. Polygons trade off real object detail for the ability to easily squish together points in 3D space (vertices: the corners of polygons). This enables Animation. Vertices can also have their XYZ 3D coordinates collapsed into 2D coordinates (called UVs) and this allows textures. It's easier for computers to handle lots of polygons than it is for it to calculate the presence of surfaces and objects from mathematical functions, which change every time the object moves. This wouldn't be a big deal for something mechanically shaped like a gun, but it would be a horrible nightmare for something shaped like a person or a creature.",
"Straight lines and flat planes are FAR simpler and faster to calculate, i.e. render, in real time. When processor time and computer memory were more expensive, this mattered a lot. Memory dictates how many shapes you can have at any one time (Ever see a tree come out of nowhere in the distance as you walk across a map? Somewhere behind you another one disappeared, freeing that memory space.) and the processor speed tells you how fast you can change their location in 3D space. Memory is a lot cheaper now, and processors are stupid fast, so you can have way more polygons and they render very quickly, which results in you clearly seeing the bad guy jump out and get you. Remember how cinematic sequences a few years ago were far better quality graphics than the game graphics? The cinematic is a stored video file that gets pulled from memory one chunk at a time and that chunk is processed into colors that are sent to the screen pixels. Video file processing is cheap, timewise, and easy to do because the file data never changes. The processor doesn't have to \"think.\" It plays beginning to end every time, so the quality can be much higher. Game graphics constantly change with player input, so the quality wasn't as good, but good enough to keep you playing.",
"Graphics are defined using math. The equation for a triangle (the basic shape for drawing) is much simpler than the equation for a circle or sphere or other round shape. That means that implementing drawing based on triangles is cheaper and faster.",
"There are a lot of things that go into this, but at the most basic there is a lot less math involved when dealing with polygons than with circles. The processors and code for rendering graphics were designed at a time when processing time was expensive; the hardware simply wasn’t fast enough to draw at the speeds needed for games. Now there is no economical reason to change. The code and standards that are in place work",
"Have you ever seen those animations or drawings where you start with a triangle and they add another side to become a square, and another to become a pentagon, and so on to hexagon, and on and on until you get a circle? Triangles, rectangles, etc, are all polygons and all polygons cane be broken down into triangles. Triangles are the simplest polygon we have. And that circle you're finally getting, if done on a computer, can be seen as a bunch of triangular shaped wedges all neatly placed to look like a shape curved at the edges. Almost like as if a pizza were made up of a thousand triangular slices instead of 8 pieces that actually do have one curved side. It turns out that any curved shape can be replicated on a screen, to greater and greater detail and smoothness, just by using smaller and smaller triangles. And triangles are really easy for computers to calculate and fill with color. The problem is that the more detail and smoothness you want, the more triangles you need. And that can really add up when you want things to look like they aren't made up of a bunch of triangles. We got started doing it this way because of the fact that visual images on a screen are made of pixels: individual points of light in a rectangular grid. So by the very nature of screen technology itself all images on a screen are geometric approximations of curves and shapes. And triangles fill the gap quite nicely between curved surfaces and the straight lines forced on us by pixel technology..",
"Graphics are made of triangles. The advantage triangles have that no-one has mentioned so far is that they are guaranteed to be a 2D plane. If you use 4 points you can make a 3D shape. Having a 2D shape to fill in makes it much, much easier to fill in a texture and apply lighting, but then you can use as many triangles as you like to make a complex object.",
"Drawing speed. By definition, straight lines are faster to draw than curved ones and I can make a very good approximation of a curved line using straight line segments.",
"Maths is the reason. Flat surfaces are simple and fast to calculate, rounded surfaces are not. So, you can choose between a game that flows well and looks good enough, and a game that's looks extremely good but is a slow slideshow.",
"there are also games ( or at least i know there was 1 game but i forgot the name ) that is entirely made out of perfect spheres. When you want realistic light effects you can use a different technique called 'raytracing' and in the world of raytracing, its faster to draw perfect spheres than polygons. With this technique you try to simulate the lightrays bouncing of walls (or spheres). this is also how real life works, so it can become really realistic But in general it is still slower than drawing polygons using the traditional technique (rasterization). its all about performance. If you can fake a good sphere with polygons, and it looks good, why not. This techinique looks more like drawing. you dont simulate lightrays bouncing off walls, but you draw the walls with a pencil basically. just draw the polygon lines in the correct way and fill it with some color. much less calculations needed and so performance increase 100 fold",
"Graphics hardware can break the polygons into individual triangles which can be batched to as many shader cores as you have. You can't really do that with parametric models.",
"Because the maths is so much quicker than any of the alternatives. A triangle in an imagined 3D world maps directly to a triangle on the computer screen. So to render that triangle, you just need to calculate what's going on at the corners, and then use linear interpolation to fill in the rest. Linear interpolation is really, really fast. (Polygons with more sides are usually just broken up into triangles.) Sometimes, linear interpolation doesn't give the best results, but that's okay. Just throw more polygons at the problem. By and large, your GPU cycles give better results with lots of cheaply rendered polygons than with fewer, more carefully rendered ones. When you start working with curved surfaces, many of your linear interpolation tricks go out of the window. It's possible that, somewhere, someone's written a paper showing how a clever compromise is possible, but if they exist, those algorithms have a long way to go before they turn up in your graphics card."
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74kxnn | why does mouthwash burn? | Chemistry | explainlikeimfive | {
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"The same reason alcohol burns when you put it on a cut. Most mouthwashes are astringents. All of the pores in your mouth react violently in contact with them. Basically, they cause the skin in your mouth to contract very quickly, overwhelming the nerves."
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74kxzk | What is bureaucracy and how does it work? | Other | explainlikeimfive | {
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"Bureaucracy is making policies and rules that govern a large group of people. In government, the bureaucrats are non-elected people that manage the population in day to day affairs that require government intervention. Since it would be impossible to manage people on a case by case basis, bureaucrats seek to standardize elements of society so that the procedures and rules apply to all people. Things that require government intervention includes: driver's licenses, marriage licenses, property management, taxes, etc. The main purpose of bureaucracy is to simplify government interactions. If everything is standard, the government doesn't need to spend too much time and money to make individual judgement on all elements of society. However, bureaucracy is often criticized because it often gets too complicated and ignores the unique characteristics of each case. Let's say you want to build a house. Instead of having a government official personally review your request and research all elements of it, the government creates a step by step process that you allows to build a house. This include permits, application forms, etc. You fill in forms A1, B2, C3, and get permit D4. These forms contain all the info the government needs and organizes it in a way that it is easy for them to process. One person can go through hundreds of these forms a day, instead of taking a week or so to individually go through all the elements. The process is easy... if all goes well. As life is full of surprises, nothing is as easy as it seems. For example, let's say you run a website from your computer that will be located in your new house. According to the government, you need permit E5 to own a property that earns income. You need to fill in form F6 to get permit E5, but doing so requires a G7 application. Don't forget, each of these forms must be handed in by person to different people and the lineup is about 3 hours for each and they each cost $100. As you can see, you are falling down a rabbit hole of requirements. If you were able to explain that your income is web based and is not dependent on the property, you would be approved with any extra headache. Unfortunately, since this is a variation the forms did not anticipate, you are shit out of luck."
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74l1qd | What is the advantage of having "custom silicon" on your hardware products (like that popular smartphone does)? | Technology | explainlikeimfive | {
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"text": [
"Custom silicon is smaller, better, and more power efficient than building electronics out of more generic building blocks. Just like injection molded plastic is superior to building your product out of LEGO. The only reason we don't build everything out of custom silicon is that there is a huge up front cost (called \"NRE\"). So the first custom chip costs $250,000.15. The rest cost $0.15."
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74l25n | Does Moore's law protect us from the singularity? I understand both a little, but not enough to know the answer. | Technology | explainlikeimfive | {
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"text": [
"Moore's law is hardly a \"law\". He essentially saw a historical trend for the number of transistors on a processor and made a statement about what he thought was going to happen in the future. Generally speaking though, it's not a sound argument to extrapolate from historical data because you're moving out of the space that you obtained your data from. The guy himself said that his law was going to die in the next few years. URL_0",
"not sure what connection there would be, but moore's law was pretty much a gimmick, it was a self fulfilling prophecy, and it hasn't held true for the past few generations."
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74lcux | Why does sitting with correct posture feel less comfortable | Biology | explainlikeimfive | {
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"text": [
"Having bad posture is due to weak or imbalanced muscles, assuming that your skeletal structure is not deformed or bent due to any abnormal traumas or growth issues. When you force yourself to sit with correct posture, what you are really doing is make your muscles do extra work - more work than they are used to doing. You have: 1. Back muscles (Upper, middle, lower) 2. Chest muscles (pectoralis major and minor) 3. Abdominal muscles 4. Obliques (side muscles) 5. Shoulders 3 and 4 are part of what is commonly referred to as your \"core\". Ideally, your back and chest muscles counteract each other's force and keep your shoulders straight and upright. If your back is stronger than your chest you may look like you are puffing your chest out all the time. If your chest is much more developed, you may look like you are hunched a little because your back muscles aren't able to counteract your chest. A similar situation exists with your lower back and abs, and with your obliques. Your body's posture is a state of equilibrium established by the opposing forces of your muscle groups while gravity pulls down upon all of them. If a set of muscles is significantly weaker than others, forcing yourself to be in a correct, upright posture means forcing THAT WEAKER MUSCLE to do extra work beyond it's usual capacity to counteract your stronger muscle groups that are pulling your body into the position they are responsible for pulling into. This will cause that weaker muscle (or muscle groups) to fatigue and feel tired - leading to your discomfort.",
"Because your bodies not used to it, over time correcting your posture re-aligns everything so it is comfortable. It's like stretching out a muscle, if you try touch your toes it can be uncomfortable, but doing it over and over until you can touch your toes makes it something easy to do and not uncomfortable.",
"I think it's also worth mentioning that it's not natural to be in ANY one position for a prolonged period of time, even if it's more physiological than other learned alternatives."
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74ldlx | Why Is It Called a "Blow" Job When The Chick Is Actually Sucking? | Other | explainlikeimfive | {
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"Because it's orgasm focused. Now, that's a bit of an oversimplification. I don't think there's a definitive answer, but if you look at sources like [this]( URL_1 ) or [this]( URL_0 ) they mention that before there was a \"blow job,\" blow meant orgasm. It's not hard (heh) to see where that connection might come from, and if you start from there, it's even easier to get to the idea of a quick and dirty bit of oral sex being called a \"blow\" job, especially in the older use of job to mean just a quick bit of business. This has always seemed the most reasonable explanation. It's not about \"blowing\" on something, it's about making someone \"blow.\""
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"https://www.grammarphobia.com/blog/2011/07/blow.html"
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74lv8w | Why do some people float on water easily when others a similar size can't? | Biology | explainlikeimfive | {
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"We're mostly water, so it doesn't take much either way to make us dense enough to sink, or a little more buoyant to float. I found out when I was little that I was almost neutral, and could float if I filled up my lungs, but would sink if I emptied them, scaring the lifeguards at the pool, so it's a pretty close balance. Women tend to be more buoyant than men because they have a bit more body fat, percentage-wise, than men, and fat is less dense than water. Fat is likely most of the difference generally because other tissues don't vary in amount and density all that much, unless you're looking at bodybuilders, who probably don't float very well.",
"It has to do with percent of body fat, as others have said. But it's also skill. A person with full lungs will tend to float, and empty lungs will tend to sink. While it may seem we're filling and emptying lungs every breath, we're not really doing so. A person who keeps their lungs more full by taking deep breaths and/or always keeping a reserve of air in their lungs will be more buoyant than a person who doesn't fully inflate their lungs with each breath. This can be used to keep yourself more buoyant. You can test this by laying back in the water and exhaling as much as you can--you'll definitely sink lower in the water than you were with full lungs. Now take a long, slow, deep breath, filling your lungs completely. You'll float better. Plus you can become more skilled at laying still and keeping yourself more afloat by making minor adjustments to your movement and arms and legs."
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74m0my | What makes chips/cookies/cereal go stale? | Chemistry | explainlikeimfive | {
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"text": [
"humidity. Their typical water content is below air humidity levels, so they'll absorb water if left in the open air, which makes them less crispy. Fresh bread on the other hand loses water to the air over time, but at the end it's that middle state with some water content, that makes it stale. Put the stale bread in the over to get rid or the last water and it gets crispy instead!"
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74m14p | how do telescopic sight or scope in sniper rifle work? The scope is few inches higher than the bullet line so how are the bullet hit the mark in the scope? | Just like the title. And super sorry for my english. my Third language | Technology | explainlikeimfive | {
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"text": [
"[Here is a helpful diagram]( URL_0 ), that shows an exaggerated view of what's going on. Bullets don't travel in a straight line, despite what it might look like. They travel up and then down in an arc, called a ballistic arc or path, just like throwing a football. Light on the other hand, for all intents and purposes, does travel in a straight line, which brings about your question. To make sure your bullet hits what you see through the scope you \"zero\" or \"sight in\" the scope or optic. This is where you pick a certain range, say 25m, where the bullet will be passing through that point where it looks like it is in the scope. It will then again pass through another point that is in line with the scope on its way down, say 300m. A shooter can pick different ranges to zero his scope, and each one will have a point where it intersects with the straight line path of the sight or scope on its way up the arc, and again on the way down. Different bullets, different barrel lengths, different calibers, etc all change what these paths are, so a good shooter will make a table or chart for a specific rifle, scope, bullet weight, amount of gunpowder, etc and calculate where the bullet will be for that particular setup at any given range."
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74m2m1 | I just can't wrap my head around Saussure's sign, signifier, and signified theory. What are they? | Other | explainlikeimfive | {
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"text": [
"Saussere said that humans just enjoy creating signs. A sign is a combination of a signifier and a signified. A signifier is something we use to represent a concept. Let's say the word \"apple.\" We all agree that that word means a specific fruit. The word is the signifier, the fruit is the signified. Lets take another example - a hat. We agree that means a piece of clothing used as a head covering. So the word hat is a signifier, and the concept of clothing as a head covering is the signified. It's possible to have words that have no signified (concepts) - or to have concepts there are no signifiers (words) for."
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74m5ai | How do spicy foods like wasabi kill bacteria? | Chemistry | explainlikeimfive | {
"a_id": [
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"text": [
"The active ingredient is [Allyl isothiocyanate]( URL_0 ) which is mainly to deter animals - caterpillars etc. and larger animals like grazers - from eating the plant. It harms bacteria too by damaging their cell membranes, which are the outer containers holding all the machinery inside their cells. When this membrane is damaged, they start leaking, stop working properly and die. The exact way it damages them isn't fully understood yet."
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74mb24 | Why is it that nail polish stays liquid in the bottle, but dries in minutes after it’s applied to the nail? | Chemistry | explainlikeimfive | {
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"Nail polish is a pigment - the color - dissolved or suspended in a liquid - the solvent. It dries out when the solvent evaporates - boils off - leaving the pigment behind. When it's in the bottle there's not much of a surface for the solvent to evaporate from, because most of it is well under the surface. And if some does try to evaporate, it's stopped by pressure building up from other solvent that already evaporated into the closed bottle, pushing down on it. When you put it on your nail, there's a thin film of liquid+pigment and it's all exposed closely to the air, with nothing to stop it from evaporating, so the solvent does evaporate quickly leaving the pigment behind, and it's dry."
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74mcch | How do doctors detect Down Syndrome in pregnancy? | Biology | explainlikeimfive | {
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"It's a two-way process. There are two markers in blood plus the measurement of the thickness of the neck in a given week of the pregnancy. The doctor checks then in a look-up table the risk of Down Syndrome given the age of the mother, the blood test results, and the ultrasound measurements. If the risk is very high, the only way to know for sure is an amniocentesis, but in that case there is a risk of losing the pregnancy, so it's not routine. There have been some advances in research that have proven that the baby's blood mixes with the blood of the mother, and the trisomy could be detected in a blood sample from the mother, but this is still under research.",
"One way would be amniocentesis. Fetal cells can be sampled by sticking a needle into the amniotic sac and sucking up some fluid. These cells are then karyotyped, which allows the chromosomes to be counted. Down syndrome is caused by an extra copy of chromosome 21, which is why it is also called trisomy 21. Blood tests and ultrasound can apparently be used to screen for symptoms, but definitive diagnosis requires fetal cells.",
"The NIPT test is the newest method for this, much more accurate than markers and much less risky than an amino. The mother’s blood contains a small number of expired cells from the placenta. If the baby has downs, it is reflected in the placenta as well. After blood is drawn from the mother, it is analyzed and they are able to actually identify and count the chromosomes for both the mother and for the baby (from the expired placenta cells). Since there is a pair of each chromosome, the expectation is that there is a relatively similar number of each chromosome. If there is a disproportionate count of chromosome # 23 then the risk is very high and an amino is usually ordered. If not, it is considered to be only a 1:10,000 risk. As a bonus, they count the X and Y chromosomes and 100% accurately determine the sex of the baby. Source: my partner had the NIPT after having a scare with the markers testing showing a 1:15 risk. The geneticist explained the test thoroughly. We were relieved that the result was that there was no down’s detected and that we were having a girl."
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74mf7f | What do people find uniquely rewarding about listening to live music that they don't get from recorded music? What is cognitively or emotionally different about the experience? | Other | explainlikeimfive | {
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"It's being produced live, *right now*, by the musicians. You're close enough to see them doing it. Nobody else can experience that exact sensation ever again. Plus there's a lot of other people enjoying that same sensation with you, and it's fun to enjoy it with them.",
"Being there live, you get to experience the energy of the crowd. That alone changes everything.",
"It's hard to bring *emotions* into a studio recording. It's so slick, has to be redone hundreds of times and is sampled together. Life/Live isn't perfect and that's what makes it interesting. That's just my thoughts on the matter.",
"You are part of an atmosphere and a social setting of people enjoying similar things to you, both of these are more intimate but mainly... the lead singer of the Black Dahlia Murder (favourite band) dripped sweat into my eye - this eye will never blink. So, memories too I guess."
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74modf | How does the police choose what cars to use as patrol cars? | Other | explainlikeimfive | {
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"I asked my father in law who was a retired lieutenant in a good sized department. 1. Safety. Car accidents are the #1 cause of death for officers 2. Space, they have a lot of gear and need seats big enough to get in and out with their vest and belt on, also a rear seat big enough to carry anybody that needs a ride. 3. Speed/handling popular police cars (almost all American) have \"police packages\" from the factory. They may have more horsepower, stiffer suspension, a pushbar front bumper. The only time I remember departments going with foreign made vehicles was BMW motorcycles and that was because BMW covered maintenance.",
"At least in Spain, usually the city council launches like a public contest (just really don't know the exact word) where they announce the requirements all the contestants need to meet, how much money will they spend, number of cars needed, in how much time will they need them, etc. They launch this for like 2 months for example. In those 2 months different car makers appeal with their different models in which they can meet all the requirements. When it finishes, the city council decides and chooses the one that meets all the requirements and is cheaper.",
"It's a bit interesting for the police because they want both: Cheap cars to drive around in neighborhoods without looking like they're trying to intimidate anyone, and powerful cars that can get places quickly and chase criminals. They usually pick rather \"generic\" looking cars and just fit bigger, more powerful engines for the latter role.",
"First off, there are only a handful of models that car makers have created specific police versions for... currently, Ford makes versions of the Taurus and Explorer for police use. Chevy has a fleet-only Caprice model and also a version of the Tahoe. Dodge offer a Charger. These models are all able to offer what police are looking for -- they generally want a larger sedan or SUV with upgraded engines, suspensions, space for gear, wiring for the additional electronics/communications, room to install a safety barrier between front and back seats, easy and cheap to repair. Typically, the forces would put out requests for bids, specifying what they are looking for a getting bid to provide that... ie. they want 10 cars a year for next 5 years, with X, Y, Z features. In the case of Chicago, our city specifically went with the Ford models during the last contract because those models are made here in Chicago so it's supporting local jobs/workers.",
"Usually the same as how any other large business makes expensive purchases. The determine what they need, they put it out for tender. Companies reply with offers, they accept the most appealing offer. The company delivers the product.",
"We’re not lucky enough this side of the pond to have Police spec cars for our normal run of the mill cars. We’ll normally have something like a Ford Focus, Vauxhall Astra, or a generic family size hatchback with an engine less than 2.0. We are now going over to BMW 2 series however. A lot of the time it is due to cost. However, sometimes it is due to the public perceptions and having existing contracts. For instance, we were offered a BMW fleet for a very good price. However, we would have had to change our maintenance contract as BMW would have wanted the servicing, and because they were concerned what he public would think if we were all driving around in BMWs. Hence we ended up with Hyundai i30s for a while, which are dreadful cars and completely unsuited. Specialised units will have more specialised cars, with traffic having big Volvos or BMW estates because of the kit they carry, with armed Response having BMW X5s, again because of the weight of kit. Also, we have completely different roads over here. As much as I’d want one, a Crown Vic isn’t suitable for a lot of our towns and cities."
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74mofu | If the eustachian tube is conected to the pharynx why cant we breath through our ears? | Biology | explainlikeimfive | {
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"The eardrum is normally airtight, so while the eustachian tube can open to allow air to flow between the pharynx and the middle ear, there's no direct pathway from the middle ear to the outside of your body. That's why your ears get \"plugged\" when the atmosphere pressure changes, such as when you take off in an airplane—the two sides of the eardrum are under different amounts of pressure and there's no direct pathway for air to flow in order to equalize them.",
"In addition to the ear drum, the eustachian tube is much smaller than the pharynx. Even if you could push air through (some people can because of missing ear drum) you won't get enough air to survive long.",
"Because the eardrum itself is sealed. If the eardrum wasn't sealed, so you could pull air in through your ear, through your eardrum, and through your eustachian tubes into your nasal cavity, then the eustachian tubes would serve no purpose. The whole point is that air can't get past the eardrum, so there needs to be some method to connect the back of the eardrum to the outside so the pressure behind it can equalize. That's what those tubes are for. If you had a ruptured eardrum, you could take air in and out through that hole, but it probably wouldn't be enough for you to breathe."
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74mprl | If font 'points' are a fixed size (1/72"), why does one font at 10 pt (e.g. Calibri) look appreciably smaller than another (e.g. Verdana) at the same point size? | [This is what I mean]( URL_0 ). | Technology | explainlikeimfive | {
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"The point size is the overall height of the space where the letters are drawn. The letters don't actually need to completely fill that height (some letters can be shorter than others and they might not even fill the space). [This is what I mean]( URL_0 ) Honestly the more annoying thing is that different fonts can have different baselines - the distance between the 'top' of the letter box and where the letter 'sits' on an invisible line. This means that if you take writing in 2 different fonts you potentially have to expand the height of the line so that they both share the same baseline position. So if you've been laying out a line of text in one font and want to use another you might have to lower the line you just made because the new font has a lower baseline despite being the same overall point size. If you don't the new font might overlap with letters from the line above.",
"Originally the point size of a font specified the height of the metal pieces on which the letter shapes were cast. That meant the total height of the letters was more or less physically constrained to fit within this dimension. But there's no rule that says fonts can't be shorter than that. (At least in the old Calson and Garamond fonts the italic faces are noticeably shorter than the roman.) With digital fonts there's no reason letters can't be taller that the font size either. There's no set-in-stone standard about how to measure the point size of a font. There's so much variability in font design that it would be very difficult to come up with a standard that matched human perception of the comparative sizes of fonts. Also, points are a fixed size now in digital typography, thanks to Adobe. There have been many other slightly different standards over the years.",
"The size being specified is the vertical height of the letters. What you're noticing is that some fonts have thinner characters and some have wider ones. Verdana has wider characters than Calibri does (particularly notable in letters like capital T, lowercase H, and lowercase P), so it takes up more horizontal space at the same point size."
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74n2ii | do people who sleep deeply get more quality rest than a "light" sleeper | Biology | explainlikeimfive | {
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"Well, the implication of being a light sleeper is that you wake up a lot. If that's the case, then obviously you get less quality sleep. Other than that, as long as you sleep for long enough and get enough REM cycles, you're fine. The thing is, different people need different amounts of sleep, so it's hard to do a 1:1 comparison without a lot more facts.",
"It’s really difficult to qualify without a Polysomnographic sleep study. If light sleep means sleep fragmentation, it can absolutely leave you feeling less refreshed. The sneakiest thing is that short arousals generally won’t be remembered in the morning. It takes a good few seconds (I’ve seen different research estimate anywhere from 8-12) to make a memory when you’re asleep. So arousals of shorter duration will impact your sleepiness the next day, without you even knowing that they happened. Sleep Apnoea is especially nasty in this regard. A diagnosis of moderate OSA can often mean that the patient is waking up every few minutes all through the night."
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74n5co | Why can’t/don’t ATMs give you money in denominations smaller than $20 these days? | Technology | explainlikeimfive | {
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"text": [
"It's how they are setup . Every ATM has canisters in them filled with cash and only so much can fit in them so the people who own the ATMs decide to put only 20s in there so they can fit more money in there. The ATM at my old job had one that only gave 20s and 1s for the vending machines. It's also easier for independent ATM owner just to fill it with only 1 denomination.",
"There's a PNC Bank by my house and the attached outdoor ATM dispenses anything from $1 bills - $20 bills.",
"Back in the '90s a handful of ATMs also used to dispense $10 bills. I think Citi was one. There are probably some out there that still do."
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74na6u | What is the difference between cosmology, astrophysics and astronomy? | I've been watching too many Neil deGrasse Tyson videos that are making me feel stupid. I feel like I should definitely have a better understanding of these terms. Are there any other terms similar to these that I should have a better understanding of? I'm interested in looking for a book that easily explains and covers all of these. Thanks for any help! | Physics | explainlikeimfive | {
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"text": [
"Astronomy is about observations, what can we detect. Astrophysics is abot the processes that might lead to what we see and explain why it changes in the way it appears to in our observations. Cosmology is about why the Universe behaves as it does. Today, that often includes things like dark matter and dark energy that we don't yet have means to observe.",
"Aerospace engineer here, I'll do what I can to help. Astronomy - The science of space, celestial objects (planets, stars, moons, nebulas...), and the physical universe. This is very broad and would include cosmology & astrophysics within it. Cosmology - the science of the origin and development of the universe. This also involves the general structure of the universe. Astrophysics - the part of astronomy that focuses on the physical nature of all the celestial bodies and it applies the laws and theories of physics to them Astrology - Because of the 'Astro' in the word, many people confuse this with the other terms. This takes the study of the movement and relative positions (relative meaning how we see them from Earth) and it tries to connect this to humans and their emotions and personalities. This is where horoscopes come in and this is NOT based on science. Someone can probably explain it better soon, but this is the basics."
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74nyj5 | When you're about to fall or spill something what is that feeling in your belly? | I just reached for my pint of water without properly looking and knocked it a little but managed to grab it before it fell, I got this sudden warm feeling in my belly and then the rest of my body. I used to get this when I would swing on my chair in school and nearly fall, is it adrenaline? Thanks, | Biology | explainlikeimfive | {
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"It does have to do with adrenaline! When you become anxious or afraid, your body's stress hormones (including adrenaline) move blood from one place to another. Your digestive system needs blood to make it work. But if you're in danger, you don't need your digestive system to work as hard any more. The blood is sent to your brain, your nerves, and your muscles so that you can act faster. The warmth you feel comes from this movement of blood. When you're done dealing with the stressful situation, the blood goes back to where it belongs. Sometimes, people who stay stressed will lose weight because their body forgets to digest food and keeps blood flowing to other places for too long."
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74o7r2 | If spiders' webs are the strongest fiber in the world. Why are not used as a material to build or create artifacts? | Technology | explainlikeimfive | {
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"It is really stretchy, like insanely stretchy, it may stop a bullet, but it will be behind you after passing through you. Spider silk is an amazing material, but it is insanely hard to get hold of, it took four years to get enough for a cloth smaller than a single sheet in 2009. Currently we cannot synthesise it very well ourselves, so maybe one day we will be able to use it.",
"Spiders are hard to work with. It's *possible* to collect spider silk and use it for fabrics but it's difficult and expensive- you can't mass produce the spiders. Spider silk is stronger than steel for the same weight, which isn't that much of a feat when you consider the almost negligible weight. A steel wire that thin would be easy to snap, BUT steel is easier to scale up, easier to mass produce, etc. We have other research into other fibers, taking what we've learned about *why* spider silk is string, without relying on an animal source for production.",
"Unlike silkworms, spiders will eat each other, so they're very hard to farm. They have instead made transgenic goats that produce the spider silk protein in their milk, but they haven't figured out how to spin it into a fiber yet"
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74og04 | How can we get money out of politics when all the people in charge of the rules are swayed by money? | Other | explainlikeimfive | {
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"Here is an honest but bleak answer. As long as politics is influencing money, money will influence politics. You cannot expect politicians to make laws that are going to affect taxes, regulations (that can cost/save money), government contracts, international trade, ect without the people and businesses that these things affect (see everyone) trying to influence the process. There is simply no way for politicians to influence money and the economy, with money and the economy influencing politics.",
"The easy answer is don't vote for either major party, or any established politicians. \"Politician\" as a job is a fairly recent invention; it used to be that it was viewed as a public service to go into politics, setting aside your regular job for a while, almost like jury duty. You'd spend your time as a senator or congressman or President, then come home to your own business. The problem with trying to fix it is that literally everyone thinks that voting for a third party is a waste of time. But that's true because everyone thinks it. If we all agreed on a third party and voted for them, they'd win elections. The *other* problem is that no third party is universally agreed upon."
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74ohw6 | Asvab scores and what they mean. How do they affect desirability for recruitment? | Other | explainlikeimfive | {
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"It's pretty simple. They score you on your assorted abilities and aptitude toward certain tasks that you would be doing in your military career. High scores = high aptitude. Recruiters have quotas to meet so if they find someone with a high asvab score, they're going to press that person to join up because they're much less likely to be disqualified down the road. I've been told that the recruiters get \"points\" based on where their recruitee goes in the career. Like they'd get 1 point for an 11B ground pounder and 10 points for nuclear power candidate. Anecdote: I scored the highest score out of my entire high school class when I took the asvab senior year. I had every branch except the Marines practically pounding down my door. Army wanted me in the Signal Corps. Navy wanted me in nuclear power school. Air Force wanted me in their electronics & communication corps (I forget the name). The look of utter disappointment on the recruiter's face when they asked if I had any medical conditions and I said \"Yep, asthma\" was so very sad."
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74ok7e | How are blood cells formed inside the bone marrow? | Please help me! I'm desperate and am about to have a mental breakdown. I looked at so many websites but all they told me was WHERE they're made, not how. I know that they are stem cells at first, but I need to know HOW they are made. Thank you | Biology | explainlikeimfive | {
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"The stem cells in the bone marrow, differentiate into the cells that make up blood. If you google hematopoiesis there should be charts on the differentiation pathway.",
"Not sure what you mean by 'How'. But I'll have a go at it. One can visualise the process of hematopoiesis as a potter making a pot. The blob of clay is like a stem cell, infinite in potential to be moulded in a shape the potter finds useful. As the pottery wheel spins he progressively makes changes to the lump of clay. As the clay moulds, it gradually becomes destined for a particular shape, either deep or shallow; round or oval etc. Accordingly the function of the formed object is decided. Similarly the stem cells start out as potentially capable of assuming any one line either the red cells, the white or the platelets. They become committed to forming a cell line under the direction of certain factors. These factors (signal proteins) initiate a series of changes. These changes include (but are not limited to) 1)decrease in size, (in some cases) 2)formation of special proteins for function (Hb, WBC granules, etc), 3) Changes in the nucleus eg loss of nucleus in RBC, folding of the lobes in neutrophils 4) Changes in DNA eg in WBC, TCR and Ig gene rearrangements to identify as many foreign antigens as possible 5) Changes in shape eg. Biconcave disc RBC, fragmented shrapnel like irregular shape of a platelet etc. The bone marrow is a huge repository/bank of stem cells. This is where all the 'clay' (see analogy above) is stored. Hence the process of hematopoiesis takes place here. The cells formed then exit into the circulation to perform specific functions."
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74onvb | How do Hawaiian fire dancers grab/eat fire? | Biology | explainlikeimfive | {
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"Fire eating isn't actually all that hard to learn - the trick is to get your mouth around the fire (and don't come in contact with it if possible), and close your lips around the shaft of the torch. This cuts off the oxygen, which smothers the fire. If done right, the fire will only be in your mouth for a second and you won't have had any direct contact. Of course, the bigger the fire, the more likely it's going to hurt a bit. Fire eaters have gotten used to little burns on the lips, tongue, and roofs of their mouths, but the lighter fluid most of them uses burns at a fairly low temperature and won't do any serious damage if the trick is done right. There's a couple of guys I've seen at the Renaissance Faire who do a cooler variation - they put some lighter fluid on their tongues, light a torch, then transfer the fire from the torch to one guy's tongue, from their to the other guy's tongue, and from his tongue to an unlit torch. So by the end of the trick they have two lit torches and they both act a little grossed out by what they've done. Really impressive when they nail it.",
"Its the fuel used... usually a white gas like paraffin oil. The fire is actually pretty cool, like shoving your hand in a tiki torch. As long as you do it right, all you feel is a little warmth.. still gotta be careful since fire is still fire but all in all it's not too hard."
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74oru6 | SMB vs FTP | What's the difference between SMB and FTP? We're doing this in class and we just finished doing both protocols but I still can't wrap my head around these 2 subjects. Thank you in advance! | Technology | explainlikeimfive | {
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"This isn't *exactly* what ELI5 is for, as you probably want something a bit technical. The ELI5 is that FTP is meant for plain old transferring files. SMB is more robust than that, and while you *can* transfer files you can also use it as a remote filesystem and do a bunch of other things with it. Please note: \"robust\" doesn't mean it's not a terrible protocol.",
"SMB and FTP have in common that they're used for remote access to files. They share this with SFTP (not to be confused with FTPS, which is FTP over SSL, SFTP is a different protocol built on SSH), NFS, WebDAV, and the largely-defunct AFP, among others. Where they differ is almost everything else. FTP is designed to have clients connect, download or upload whole files at a time, and go away again. That's great for distributing things that don't need changing, but not great for anything else. SMB is a *whole lot more* than that. Quite apart from files, SMB also handles access to printers (and a bunch of other stuff too, like sharing of serial ports, interprocess communication, and more - but barely anyone uses it for more than files and printers). Even narrowing the focus to files, it has a *completely different* model to that of FTP. Where FTP treats the files it serves as a sort of library, operating on whole files at a time, SMB acts as a remote *filesystem*. You can edit files in place with SMB, whereas the best you can manage with FTP is to have a client feature that fakes it (by reuploading every time you save a new version, and hoping nobody else is doing the same thing). Like local filesystems, with SMB you can place *locks* on files (which is particularly useful when altering them in-place, as mentioned before). SMB also has support for comparatively complex authentication schemes built in, whereas it has to be \"tacked on\" to the outside of FTP. That allows more complex, fine-grained access control, as well. Ultimately, they serve different purposes. If you want a rudimentary equivalent of Dropbox (albeit probably without automatic synchronisation), FTP does the job (though you should really use FTPS, or better yet SFTP). That's especially good if it needs to face the net at large. If, on the other hand, you want to share a proper filesystem between multiple users on the same local network, SMB is a far better option, especially if you need to muck around with shared peripherals as well."
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74ovhf | If plants can convert Carbon Dioxide into Oxygen, why can't we create machines to do the same thing to control the amount of CO2 in the environment? | Chemistry | explainlikeimfive | {
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"That's called carbon sequestration, and it is a thing we can do. There would need to be an ENORMOUS amount of it to counter how much we're putting into the atmosphere. It's easier to reduce the carbon output. It would be like trying to justify expensive desalination plants to make fresh water because of our huge demand for waterslide parks.",
"We can, but we shouldn't. The technology is undeveloped, but even if it were extensively developed it would be bad to implement it. We convert oxygen and hydrocarbons to CO2 and water to make energy. ie burning wood, charcoal, coal, natural gas, and liquid oil products. Forgetting about the issue of scale-able technology, reversing this process is going to require more energy than we got from the process to begin with. So if we built such a device, and then powered it using fossil fuels of some sort, we'd be net adding CO2 to the atmosphere. We'd add more than we could suck out. Until we're no longer burning hydrocarbons for energy, its detrimental to actually try to run such a machine. It's always more efficient to just stop a hydrocarbon power source from operating. So we need to focus on making that a reality first. There are more practical limitations as well - CO2 concentration in the atmosphere is only around 400 parts per million. It's very diffuse, so it's had to collect it in large quantities. Now, there is a more middle ground - it may make sense to run such CO2 sequester machines while still burning fossil fuels if our grid energy is made CO2-free. If we run our cars and boats and planes on fossil fuels, and then make those fossil fuels from carbon collected at these plants, we'd have a stable carbon-cycle. But we need to get a CO2-free grid first. Though once we're there, the Earth's natural carbon-sequestering processes could probably handle the load anyway. The Navy is experimenting with a small version of this - if they can extract CO2 from ocean water and make jet fuel from it, then the wouldn't need large fuel ships constantly running fuel to the carrier battle groups. Aircraft carriers could make fuel directly for their planes using their nuclear reactors - and fuel ships could be replaced with nuclear reactor ships that make the fuel as they go, instead of constantly running off to nearby ports in unsavory areas to get more fuel. They don't know yet if they can make this efficient enough to be practical, but it is a goal. And along those same practical lines, the grid would likely have to be nuclear. Wind and Solar just don't have enough energy scale-ability. Consider that to capture the CO2 released by burning a gallon of gas, you'd need to spend more than a gallon of gas worth of energy. If we want to drop CO2 levels by 100 parts per million, it's going to require *more* energy than we got from burning all the coal and oil it took to add 100ppm of CO2 to the atmosphere (minus the work the natural environment does - which is significant). The US grid runs on 450-500GW of power. Once you made that energy all 'green,' you'd have to add on top of that probably 100GW or 200GW more of energy production devoted entirely to powering sequester machines to make a significant dent in CO2 reduction. If you wanted to actually reverse the CO2 levels and not just stop them from increasing. 100GW would take 50 nuclear power plants, or about 60,000+ wind turbines.",
"Actually, the trees convert CO2 into trees. Trees, like most living things, are called carbon based life for a reason. Look at the size and mass of a tree. The majority of its mass is from carbon atoms. The carbon atoms came from the air. So, a tree, which can weigh many tons, will contain many tons of carbon. That carbon was taken from the atmosphere and used to make a tree. It takes energy to do that, and it was almost all solar energy. So, to replicate that, we'd have to make machines that use solar energy to take the carbon out of the atmosphere and use that carbon to build something solid so the carbon doesn't return to the atmosphere. But we already have machines that do that. They're called trees. A tree is a wonderful machine that takes tons of atmospheric carbon and turns it into more tree. To return that carbon to the atmosphere...burn the tree. Most of that stored carbon goes back into the air. [Edit] about 50% of the entire mass of a tree is from carbon. At the extreme end, the General Sherman giant Sequoia tree weigh about 1,910 tons, which means it is holding 805 tons of carbon that it pulled out of the atmosphere.",
"Trees, grasses, and seaweed are cheaper and don't require electricity to run. Keep in mind the scale of these operations. But [we are now building machines]( URL_0 ) that do exactly what you are suggesting.",
"We can. It just takes energy - a *lot* of energy. Right now, we have a situation where: * Producing X amount of energy emits Y amount of carbon * Recapturing Y amount of carbon takes more than X amount of energy. So in order for these machines to be useful, we need to either * Make producing X energy emit much less than Y carbon (such as by moving our energy mixture to include more renewable and/or nuclear energy and less carbon-emitting energy) * Come up with new technologies to make recapturing Y amount of carbon take much less than X amount of energy. In the long run, we probably need to do both, on large numbers. But hey, you could sort-of do it right now with existing technology and plants both, if you had enough money to throw at the problem! You could grow a lot of biomass (say, fast and dense-growing plants on land not currently being used for critical food supplies) and then convert it to biochar (and syngas, don't forget syngas...) using only renewable power to cook the stuff. The problem is, while biochar is both useful and a way to store carbon, it's pretty unlikely anyone wants to buy *enough* biochar to make a serious dent in the elevated levels of atmospheric carbon. So you'd just have to shovel the rest of it down a hole - benefiting the world, maybe, but not you personally - and so, who would pay for that? (Note: this is not an unanswerable question. Pretty good solutions involving cap-and-trade or a carbon tax combined with carbon credit and a well-audited international program of project certification have already been mostly hammered out.)"
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74owxj | Why does everyone say to drink lots of fluid when you have a cold? | I have a cold and everyone says drink lots of fluid. What does this actually do if I drink lots of fluid as opposed to not drinking fluid while having a cold? | Biology | explainlikeimfive | {
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"Your immune response to a viral infection is more demanding on your body than if you weren't actively fighting an infection. Simply put, you need more fluids and electrolytes to build the things to fight the injection. It's also easier to not want to eat or drink while you're sick adding to the lack of proper hydration. Fever, chills, hell even just the increased mucus production are draining your fluids quicker than normal. Edit: TIL you can't mention electrolytes on reddit without at least a handful of idiocracy references being thrown at you. Nice. Edit again: \"Fight the Injection\" is my new band name. Don't hate. And thanks for gold ? Not sure what it does but thanks",
"Honestly, not many of the top comments here make sense based on physiology. Generally, drinking fluids and electrolytes (ideally something like dilute gatorade) is good when you are sick with something that is making you lose fluids, such as a diarrheal or vomiting illness. When you have watery diarrhea, the bug making you sick is tricking your intestines into secreting lots of electrolytes into the lumen of the intestines, and water follows salt. So you end up losing large volumes of water and electrolytes, which may lead to dehydration and electrolyte imbalance (which can be life threatening). In order to replace those, you want to give your body water, electrolytes, and glucose to power the electrolyte-absorbing pumps in your gut... in other words dilute gatorade. For upper respiratory colds, water or soup may be helpful for relieving the uncomfortable symptoms of dry throat and thick mucousy cough, but physiologically it won't make much difference. Source: medical student studying for boards Edit: Didnt realize this blew up. I encourage everyone to read the comment replies, as several physicians have responded with further explanation. Additional fluids are necessary to compensate for the increased metabolic demand, as well as losses through mucous, sweating, etc.",
"I'm a physician completing my residency in internal medicine. The answers here miss the mark in that infections kill you from hypotension (low blood pressure) because of fluid loss and shift. The components of this process are: -poor intake: people lose their appetite while sick -gastrointestinal losses: vomiting, diarrhea -insensible losses: sweating which is typical in febrile illnesses But the primary reason infections kills you is septic shock: dysregulation of your immune system leading to inappropriate dilation of your arteries/veins, thereby dropping blood pressure. Additionally, your vessels become 'leaky' and you get distribution of fluid from your intravascular spaces (i.e. in the arteries and veins) into your extravascular spaces which include interstitial tissue that make up your organs. So when you come to hospital with a serious infection, the most important components of what we do are 1) intravenous fluid, typically 30ml/kg right off the bat intravenously and 2) antibiotics, in that order. The sicker someone is, the more important that order is because what'll kill you is the low blood pressure. In most cases, you'll be fine, but influenza kills something like 30k people in the US every year. Malaria has killed more people than anything in human history. So drink up.",
"These comments about how dehydration and low blood pressure will kill you and everything are right, but for a normal healthy person that's not the concern. I recommend drinking lots of water for respiratory sickness because it can help you get healthy faster and with less complications. When you're sick you have mucous and nasty gunk pouring out of your nose and draining all day long. When this mucous is thick it will sit in your nose and slowly drain into your throat or lungs. Thick mucous is harder to cough up, which causes more irritation and stress to your lungs. The longer your lungs have this mucous in them, the more likely an infection in the lungs will occur, which is more serious and will cause you to be sick for much longer. Staying really hydrated caused the mucous that is secreted to be more watery and thinner. Thinner mucous is easier to cough up and you're more likely to get better without further complications or infections. But it also makes you pee every half hour so it's totally up to you.",
"Because you can lose a lot of fluids when sick. It can also be easy to forget to drink when sick, especially if your throat hurts badly.",
"True ELI5: More fluid = more fluid dragging germs through your lymphatic system (which kills bacteria/viruses) = more killed = you get better faster. Yay. Source: ER Doc",
"Colds tend to cause mucus in the belly, making you feel full and nauseated. There's no room for food, and more water makes your stomach spew one way or the other. You can lose fluids by urination, blowing mucus, breathing out your mouth all day, sweating under a blanket with chills, pooping water instead of solids, and vomiting. All the while, you're not taking any in. Small children are 3/4 water by weight. So a 40lb child is around 30lb (or pints) of water. A 40lb child can easily vomit and poop 2 pints of fluid in seconds; an adult, a whole gallon (8 pints or more). You needed that water to make blood, fight infection, move food around, and cool yourself with sweating. Now it's gone, and it's uncomfortable to drink more. That's why it's important to drink any time you can when you're sick.",
"To put it simply, you need fluids to maintain proper hydration. Especially water or teas. No caffeine. Colds tend to dehydrate your body thus you need to replenish your fluids that the \"cold\" is taking away from your body. Plus fluids help in loosing up congestion in your affected body parts.",
"Think of your body as a star craft map and you're immune system is playing Terran. A cold in the form of a MASSIVE zerg rush is attacking and your defenses won't last forever. You need a bunch of minerals to build units to counter the zerg (cold). In this case, fluids are the minerals used to pump out immune system units to dunk on the zerg cold.",
"let's say you're really really sick - diarrhea and vomiting. you're losing fluids alarmingly fast if it's this bad. drinking lots of fluids can help prevent dehydration and help flush your kidneys. Also when sick i tend to sweat a lot and don't realize how badly i need more water sometimes. often the illness can make me not want food/water for days and without an effort to consume the fluids at least i could be in bad shape.",
"Not seeing any top response that answers it, so here is my bit. Drinking fluids when youre sick doesnt actually do anything to \"boost\" your immune system, it is more something to remind people, \"hey, you need to drink water to live.\" When people are sick with a cold (which is usually caused by a virus), its important to keep your body working as best as possible to deal with the infection, and that means you need to make sure you arent dehydrated. Dehydration in general is a bad thing to have as it impacts your whole body and, for simplicity sake, creates more problems your body has to deal with so that it can get back to dealing with the cold. When people are sick, they tend to eat and drink less, either because they cant handle eating/drinking anything or they just have a reduced desire to do so (BTW, people also get water from foods they eat, not just drinks--remember when people say cucumbers are like 90% water?). On top of this, sick people tend to sweat more (from fever), vomit, and potentially have diarrhea. Putting together the fact that a sick person is taking in less water and putting out more water, it is possible to see that a sick person runs the risk of becoming dehydrated, and therefore at risk of becoming even worse off. TL;DR: You should drink fluids to make sure you dont get dehydrated, especially when sick.",
"Also provides hydration to secretions that occur and eases their elimination. Consolidation, particularly in the lungs, can be problematic.",
"To add on to some of the advice, drinking a lot of filtered water actually reduces electrolytes in your body, because all the natural minerals have been taken out. The filtered water will flush the electrolyes out that you have consumed through food. The best thing to drink is some hot bone broth or even chicken stock because of the sodium and collagen. Even spring water with minerals would be okay.",
"There is no evidence it helps ([Citation]( URL_0 )), but it seems like a bland \"couldn't hurt\" kind of advice. It's the same reason doctors recommend peeing after sex for UTIs. There's no evidence for it, but meh, gotta say something.",
"Water is the key ingredient for life on earth, it is necessary for all basic bodily functions. Your body is 70% water and when this percentage gets too low all sorts of problems start happening. Increased production of mucus and phlegm deplete the body of water when someone is sick, so the body needs more water intake during that time. It also keeps the mouth and sinuses moisturized, which helps a person maintain a level of comfort when that area is inflamed.",
"I'm an IM physician(PGY-1). Drinking water helps with many things, namely hydration. You need to stay hydrated when you are immunocompromised since you might be experiencing fluid loss via, diarrhoea, vomiting, perspiration, and simply having no appetite. Further, you need electrolytes for many pumps to work in your body and normally with the presence of the above-mentioned things we experience electrolytic imbalance.",
"A lot of illnesses dehydrate you, and that makes it way harder to recover. When I had mono I probably took an extra month to recover just because I wasn't drinking much and my body was burning through whatever I took in.",
"Water is used by the body to make mucus. When you have a cold your body makes a lot of mucus to fight the get rid of the cold. If you don't drink enough water you will get dehydrated because your immune system will use up all the water in your body to fight the cold. When you drink enough water your nose will run and your lungs will start coughing up mucus. This will help your body fight off the cold. Stay warm rest sleep drink plenty of water. Works for hangovers too",
"When you are sick you tend to sweat more and/or make a lot of mucus which are both mostly water. The more hydrated you stay, the better your body can defend itself. Also, there are lots of bacteria or virus in your system, drinking water helps a little to flush it out of you, or flush out the dead bacteria/virus that your body has killed. My friend's family had a rule when you are sick - drink 2 glasses of water in the morning. Whenever you go pee, drink a glass of water right after.",
"The biggest reason is the benefits it has for your immune system. Extra water can help your body get rid of harmful substances quicker which lets the body focus on the sickness.",
"More fluids = more stuff moving around more efficiently. Your body goes into defense mode by cranking up the heat burning up your fluids faster. Water cools the body temperature while maintaining it defense efficiency speed.",
"When you have a cold, your nose runs, you might sweat more, and you might puke. That means you're losing water a lot faster than normal. Plus, it can reduce appetite, so you're getting less water from food. This means it's easier to get dehydrated. Water isn't necessarily the best fluid to drink. When you lose water, you're also losing salts (electrolytes). Drinking a non-caffeinated sports drink replenishes those electrolytes. Or you can get oral rehydration powder (such as Pedialyte), which is a mixture of electrolytes that you add to water, to rehydrate you most effectively."
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74pb6i | Where do you find the number for pay phones? Like in movies a boss would call the exact phone you’re walking by on the street. | Other | explainlikeimfive | {
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"At one point in time, pay phones had a little strip above the keypad which had its phone number. That’s just my memory of them from childhood. I don’t know that I’ve touched one as an adult. As for someone just magically knowing the number of the phone you’re walking by; probably the same way they know where you are, movie magic."
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74pm38 | why does ice crack when it's put in drinks?? | Physics | explainlikeimfive | {
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"text": [
"Thermal stress. The liquid is relatively warm compared to the ice. When you put the ice in, the outer layer of ice quickly warms and expands. This puts stress on the ice as the inner core is still cold while the outer layer is expanding, resulting in the ice cracking. Note that this can also happen to plates and bowls. For example, putting cold ice cream in a warm bowl can lead to a similar result depending on the material and integrity of the bowl."
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74py7b | How do programmers incentivize AIs | I often see it stated with little explanation in articles about AI research that programmers use incentives to get Artificial Intelligences to do certain tasks. They never say what the incentive is or how it works. How exactly does one go about giving an AI an incentive and what would that incentive be? | Technology | explainlikeimfive | {
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"do07wtu",
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"Incentive is a misleading word. It's just a weight. Let's say it can do action A, or action B 50/50. If it picks right, you up the score +5, if wrong, -5. So if an answer should be A, and the AI picks A, it becomes 55/45, with a stronger weight towards A being the way to do things. It's not an actual consciousness, so it's not incentivizing like a person. it's just math that reweighs things if it gives the correct output. Here's some previous posts on the topic: URL_0",
"Incentives are basically what the AI wants. It’s usually expressed as a number and the AI is just finding ways to maximize(or minimize) that number. Let’s say you are making an AI to play Super Mario Brothers. The incentive would be the level count. You can also have several incentives that have different weights. So after maximizing the level count, you might want to maximize the score, or remaining lives, or how far to the right you got on a certain level. Level count is the most important, so moving to the next level might be worth 100 points, and the other things are worth 10 or 20, but that’s the idea. One of the complex parts of AI is figuring out how to set these incentives so that the AI does exactly what you want."
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74q2kq | What led to the creation of the Knights Templar and what was their MO? | Why did they even exist after the church regained power? | Other | explainlikeimfive | {
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"do0c8u8"
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"text": [
"During the Crusades, the Church controlled Jerusalem for a time, and this attracted pilgrimages to go see the holy land. The trip from Western Europe to the Levant was rough and dangerous. The Knights Templar were formed as a monastic order charged with securing the safety of pilgrims. Besides safety, they also served as a basic form of banking for pilgrims. Before you left, you'd deposit your valuables at a local Templar place, get a certificate of deposit, and afterwards you could either withdraw once you returned, or get an equivalent in treasure when you were in Jerusalem. This financial dealing made them relatively powerful. Despite the myths around them, their utility and purpose waned as the Muslims recaptured Jerusalem and the surroundings. Due to their power and ongoing feuds with the Knights Hospitaller, the French king eventually ordered them all arrested, and pressured the Pope to do the same. Some were killed, but most were given pensions and allowed to leave, or became absorbed into other monastic orders."
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74qb1p | Why do our imaginations die when we grow up? | Other | explainlikeimfive | {
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"do0bzvk"
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"text": [
"They don't. We just have other stuff stuck in our minds that keep people from daydreaming. Some people, however, keep on daydreaming and having vivid imagination. It's not that people lose imagination as they grow up, but that we have less time to imagine things. Also, being exposed to classes, logical thinking, scientific method, etc. prevents us from coming up with mystical explanations for every dat stuff, like imagining the earth is round, or that god is peeing when it rains."
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74qdot | Why do Catholics have confession, but not Protestants? Could a Protestant confess to a Catholic priest? | Other | explainlikeimfive | {
"a_id": [
"do0b4f5",
"do0weq9"
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"text": [
"The whole basis for the Protestant Reformation was that man does not need an intercessor between the individual and God. Protestants do not believe that you need to confess your sins to a priest who replies on God's behalf. A Protestant believes that man can directly confess to God.",
"In Catholicism, mortal, or very serious and deliberate sins, have to be confessed to a priest to obtain absolution. Priests are regarded as \"other christs\" who stand in the shoes of Jesus Christ to absolve mortal sins. If a Confirmed Catholic dies with any unconfessed mortal sins, they are at risk of damnation. Some Protestants, like Lutherans and Episcopalians have confession, but it differs from Catholicism in some ways. The first is that confession to a minister is not necessary to obtain salvation. The second is that it is not a sacrament (although some Episcopalians in recent years claim it is). Confession is part of the Sacrament of Reconciliation or Penance in Catholicism. Protestants have an understanding of \"the priesthood of all believers\" that effectively cuts out the need for priests in the Catholic understanding. The Protestant minister, called in some denominations a \"teaching elder\" is basically a Christian who specializes in their religion and went to a seminary to study in depth the Bible, theology, how to give sermons, how to manage church buildings, how to council people considering marriage or struggling in marriage, how to council the sick and dying, and other responsibilities. They may also ordain the minister to be stewards of the sacraments (usually the Lord's Supper and Baptism) and administer them appropriately. Unless a Protestant was confirmed in the Catholic church, they are not expected to confess to a priest. I'm sure they could if they wanted to, as confession is not closed in the same way communion is."
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74qdza | If houseflies only live for a few days, how do they survive winter in colder areas? | Biology | explainlikeimfive | {
"a_id": [
"do0nyex"
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"text": [
"Houseflies actually live for several months, not a few days. Considering *house*flies tend to live indoors and reproduce indoors, it's possible for them to just continue reproducing through the winter indoors. You also have to consider that many places, like dumpsters, or trash heaps, always have flies, because the decomposition keeps them warm."
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74qgtb | Instability of dimensions higher than the 10th/11th | Physics | explainlikeimfive | {
"a_id": [
"do0oogi"
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"text": [
"The theory that there are X dimensions total derived from the mathematics behind string theory, specifically a variant called M theory. The total number varies slightly depending on what maths you follow. Unfortunately I don’t think you could ELI5 the mathematics to a person without advanced physics/math education. Dimensions beyond the fourth have never been observed or experimentally proved. Searching for evidence of higher dimensions is one goal of particle accelerator research. According to string theory, the higher dimensions (5+) are “compacted” around the smallest subatomic particles (possibly quarks) and are too fine to detect or change with our current technology. The sci-fi novel Three Body has probably the best explanation of how the higher dimensions would relate to reality as we experience it and the kinds of things a civilization could do if it were able to manipulate higher dimensions."
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74qsz7 | Hydroplaning | I remember learning about it in driver's ed, but I haven't heard or seen anything since. What is it and how does it work? | Physics | explainlikeimfive | {
"a_id": [
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"text": [
"Water is an uncompressable fluid. When you drive through a puddle iin your car, the tread on an all season radial generally squirts the water out the side, keeping the rubber of the tire on the road where it has traction. However, if the water is deep enough, the tread worn enough, or the car going fast enough, the tire doesn't have time to move all that water sideways before it spins. The result is that the tire skims over the surface of the water instead of sinking down to the road surface and gaining traction. In a modern car with anti-slip technology, minor hydroplaning can be felt while driving as a kind of a rumble as you go through wet patches of the road. If you attempt to turn while planing, you'll just keep going in the same direction you were going before, until the front tires hit asphalt again and then turn the car in the direction they're pointed. Note that the results of hydroplaning will differ depending on front/rear wheel drive, center of mass of the vehicle, and how many of the tires are up on a plane instead of touching the road. When the front tires are skiing over the water surface, try to keep the car pointed in the forward direction if possible -- because when you eventually hit the road, you'll go whatever direction the tires are pointed, and you don't want that to be into oncoming traffic or off the road."
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74qzj4 | How do certain medications evoke a physical change in the body such as reducing inflammation? | Biology | explainlikeimfive | {
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"text": [
"I can explain the mechanism of let's say Aspirin (or Ibuprofen or paracetamol, there's not much difference). If you take aspirin, it gets in your bloodstream and inhibits an enzyme (which acts like a simple converter; it converts useless substance A to useful substance B, without being affected by the chemical reaction itself). When this specific enzyme, which is called \"cyclooxygenase\" is inhibited, it produces less prostaglandines. Prostaglandines are inflammatoric transmitters, which flow around in your blood and tell certain cells to do stuff. This happens like a lock and key, the prostaglandine is the key and the cell has different locks on its surface. For example there could be a lock (=receptor) for \"get larger\", \"more activity\" or \"shut down completely\". So when a prostaglandine docks on one specific receptor on the inner layer of a blood vessel, this cell lets more water though. When this barrier gets less tight for water, the water will flow into the muscle which is on the outside of said blood vessel, and the muscle will swell. This is one symptom of inflammation, which is caused by one sort of prostaglandine. The other symptoms are being red, being warm, pain and not functioning properly. Each symptom is transmitted by one sort of prostaglandine. So when there's aspirin present, less prostaglandines are produced and therefore there is less inflammation. This doesn't affect the cause of the inflammation, like trauma or infection, so bacteria can continue to grow. I hope I have explained it well since English isn't my first language, feel free to ask any questions :)"
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74rdmn | Why people can spell a word for years then all of a sudden go "Did I spell that word right?" even though it's correct? | Other | explainlikeimfive | {
"a_id": [
"do0m7kz"
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"text": [
"Well, I teach in a multigrade classroom and when you're grading spelling tests and see a word you definitely know how to spell, spelled wrong enough times it's hard to remember the correct spelling. I'm sure you've seen most words misspelled especially in messaging or on Reddit, Facebook, etc. If you're looking toward past experiences your background knowledge could be a bit cloudy."
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74ri1b | Why do some people shake their legs when sitting down? What are the benefits? | Biology | explainlikeimfive | {
"a_id": [
"do0q7tv",
"do0nmf4",
"do1178e"
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"text": [
"People's muscles 'twitch' constantly to keep toned. Lack of twitching leads to loss of tone over the entire body. Some people's 'tone twitching' is at a lower frequency but higher strength than others. So they are shaking their legs to maintain toned muscles - they just shake them more but less frequently than most people do. In fact most people 'twitch' in such a fashion that it's undetectable and they don't really know they are doing it. Same reason behind fidigting. The only benefit of being a 'slow twitcher' or fidigter is burning slightly more calories a day. So they tend to be thinner.",
"Interestingly, there was a study I recall from many years ago that compared people's BMI and whether they had this kind of nervous impulse to move or not, and found thinner people were twitchier (TLDR version of course), or something close to that.",
"I've seen it here explained before as blood pooling in your lower legs is not moving around as much as your heart would like it to, and instead of stressing the heart further, the brain just sends some signals to the leg instead to get things moving."
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74rqgc | Why does our saliva “change” before we are about to vomit. Whether it be a rapid build up of saliva or saliva getting runny. | Biology | explainlikeimfive | {
"a_id": [
"do0m7wy",
"do0m8pe"
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"text": [
"The acid in our stomach is harmful to unprotected tissue such as within the mouth, so more saliva is produced to help protect the mouth and dilute the acid.",
"saliva can help protect against the damage of stomach acid that comes up with vomit. coating your mouth in as much saliva as it can is a way to defend it"
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74rqjg | Does having a random alpha+numeric+symbol password reduce exposure in compromised email data breaches? | Just received notice from haveibeenpwned that my email is part of multiple data breaches. when email info is compromised, what are the capabilities? I assume the hackers gained access to the salted hash password file. does having a random string strong password reduce exposure of brute forcing via rainbow? does a password that's 10 character random gen password like "jD02j-#2Ao" make it less likely to be flagged as a positive password match as opposed to what has been toughted as more secure "1quickbrownfoxjumpsover1lazydog" | Technology | explainlikeimfive | {
"a_id": [
"do0svks",
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"text": [
"Brute forcing isn't the only way hacker try to guess passwords massively. One of the most common ways is through \"dictionary attacks\", and could be refined through word association. In your example, the password \"jD02j-#2Ao\" has 10 characters, and you would need to include all letters, numbers and a lot of symbols in a brute force attack in order to guess it. Let's say there's a set of 100 characters to pick, so that password is one of 10^100 possible combinations. On the other hand, the password \"1quickbrownfoxjumpsover1lazydog\" has nine words, and most of them are pretty common (in [this]( URL_0 ) list of the 3000 most common words, only \"fox\" and \"lazy\" aren't on the list). Let's suppose all of them are on the 5000 most common words list, so it's one of 5000^9 possible combinations (~2x10^33 ). But there's two notes on this: first, using \"1\" instead of \"one\" is a common substitution, and hackers tend to take them into account (also 1337 or SMS language). Second, that specific combination of words is a common phrase, and even if the hacker doesn't know it, it could be created from scratch if the algorithm can forms sentences using word function (so, \"adjective+noun+verb\", and combinations). It's difficult to calculate how much this fact lowers that 5000^9 , but it surely lowers it.",
"> I assume the hackers gained access to the salted hash password file. This is the best case. If hackers breached the site's security to get the password, we have already established that the site does have its security flaws. Whether or not they salted, or even hashed your password (or if they just stored it in plain-text) is uncertain. > does having a random string strong password reduce exposure of brute forcing via rainbow? Depending on your meaning of strong. If you mean a variety of characters, intended to thwart dictionary attacks and the like, then no, that will have no effect on a rainbow table. If you mean the length of the password itself, then yes, that could help. If the rainbow table was designed for passwords of lengths shorter than your own, then they won't be able to find your password in the 'table'. Also, if the website did salt your password, then this will render their rainbow tables completely useless even if your password was something simple like \"pa$$word\". Rainbow tables are effectively compact, but slightly slower lookup tables computed of the 'standard', non-salted hash function. However, I should address that having a stronger password will help thwart regular brute force attacks (just trying every single password to see if its hash matches) and definitely helps against dictionary attacks (trying passwords composed of typical English words + a few added symbols / digits, and often l33t t3xt). > does a password that's 10 character random gen password like \"jD02j-#2Ao\" make it less likely to be flagged as a positive password match as opposed to what has been toughted as more secure \"1quickbrownfoxjumpsover1lazydog\" Usually yes. Enough added characters in the longpasswordofjoinedwords will make it harder to crack than a more complex shorter one, but only for enough characters. Looking at it in a simplified case, lets say we want to calculate how many passwords there are of each type (with specific length and character set). If you have a password 12 characters long but all lowercase, that would be 26^12 = 9.5e16 possible passwords since there are 26 possible characters and we choose 12 (possibly duplicates, otherwise we'd have 26! / (26-12)! ). For the complex password, lets say its 6 characters long, but can be uppercase, lowercase, digits, and any of 8 specific symbols (!@#$%^ & *). That means we have (26+26+10+8)^6 = 1.2e11 possible passwords. However, the actual number of possible 16-lowercase-letter 'passphrases' (as they call them) would be lower, since not ever combination of letters makes a word. So a hacker may just pull words from an English dictionary, and try combinations of those instead. There's about 9k 5-letter (commonly used) words in the English language, and 18k 6-letter words. It'd take about 3 of these words to produce a 16-letter passphrase, so if we just computed all pairs of 3 as an upper bound, we'd have (9,000+18,000)^3 = 2e13, which is 3 orders of magnitude lower than our previous estimate. Of course this is a very rough estimate, and of course has its flaws, but I think you see the point I'm making. Anyways, in regards to your breached accounts- as always its a good idea to change your passwords on everything that used that same password, its even a good idea to have a different password for each website/app. Passphrases (as shown in my example) are stronger than complex passwords, and are easier to remember. If you do this, your main concern should then be what other personal info got leaked. Any phone numbers, full names, birth dates, that stuff. Getting your email address leaked can be a pain since you'll likely get lots of ads (due to them selling it to advertisers), but isn't as bad as potential identity theft. If any important info like that got leaked, definitely ask around (right away) and figure out how to handle that. I have no clue where to start on something like that, but I'm sure you could find someone who knows."
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74rzn0 | How does satellite communications constantly work since it's not always lined up with your location and could be on the other side of the earth? | Other | explainlikeimfive | {
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"text": [
"Satellites used for communication are generally in Geostationary orbit, that means that they're always over the same spot on the Earth so you're always talking to the same satellite. That satellite has line of sight to either a ground station or another satellite which has line of sight to either a ground station or yet another satellite until at least one of them can see the ground station. This technique ensures that there is always a satellite lined up with your location, and that your message can always get to its destination Some groups are starting to use low orbit satellites which means they move relative to you, but they're putting significantly more in orbit so you're always able to see at least one"
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74s1dy | Why do different types of alcohol cause different drunk feelings/behaviors? | Biology | explainlikeimfive | {
"a_id": [
"do0r3ko"
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"text": [
"It's all just ethanol. Changes in the way you feel are caused by what's with the ethanol (more sugar, less sugar) and your own personal expectations and psychology."
],
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5
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74s59n | Why is the average height so much greater in certain parts of the world? Why aren't people in general about the same height? | Biology | explainlikeimfive | {
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"do0puzg",
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"text": [
"Genetically, almost all have similar potential. But nutrition plays a big part. Nutrition in them, their parents and even grandparents affects height. Ever notice that second and third generation immigrants to Western countries are usually a lot taller than their first generation grandparents?",
"The big thing is genetics. While yea, everyone has the ability to be the same height, over time humans have moved away from each other and carried with them those particular genes which allow them to be best suited for that area. That combined with the fact people don't generally move outside their biome and little piece of earth, communities stay rather stagnant, and things a selected genetically. Add in the cultural aspects (in some cultures, taller people are preferred over shorter) and environmental (darker skinned people are less likely to get cancer in the sunnier areas like Africa) and certain regions begin having certain specific qualities in humans.",
"I find the Netherlands an interesting example with the tallest of both sexes in Europe. It is a tiny country bordering Germany and Belgium who are not. The people are not genetically that different from one side of the border to the other. One factor is that the Dutch have a programme where babies are measured and weighed. Those who are not growing fast enough receive extra food (usually milk based) from the state."
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74s6s9 | Why is Yellowcake uranium a sulfur yellow color when normal uranium is lead colored? | Chemistry | explainlikeimfive | {
"a_id": [
"do0q8v7"
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"text": [
"Yellowcake uranium isn't pure uranium, it's uranium oxide. Just like iron turns orange when it oxidizes, uranium turns yellow. The act of bonding to oxygen changes the electronic structure of both atoms, and changes the way they interact with light."
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74spp6 | Why do no carb and all fat diets work? Shouldn't they become fat from eating fat? | Biology | explainlikeimfive | {
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"text": [
"Lets break this down a bit because the main problem is duplicate names Fats in foods are lipids, fats on you are adipose tissue. Everything you eat gets broken down into its basic blocks which get used for energy(calories). If you're consuming more calories than you burn then your body will pack some away in adipose tissue for the future. It doesn't matter if those calories come from lipids or carbs or sugars, your body packs them away the same What matters is calories in versus calories out",
"Fat does not make you fat. Excess carbohydrates becomes fat. The 1980s anti-fat messaging was wrong. If you have heart disease or numerous other conditions you should watch what you eat.",
"Calories in vs calories out is an overly-simplified and incorrect model of human weight gain. What we want to know is what causes people to store fat and how can we change how that happens. There are a lot of factors to weight gain, but the main mechanism is the absorption of fatty acids by fat cells. This is mainly stimulated by the presence of the hormone insulin in the blood stream. So what stimulates the release of insulin? Simple carbs, especially sugars. This is why no carb diets work. By not having carbs during a meal, blood insulin stays low and fat cells do not absorb fatty acids (or at least they absorb much less). If you're interested, here's an [hour long lecture by Gary Taubes]( URL_0 ) about why the calorie balance model is wrong and how hormones regulate weight gain.",
"It's all nutritional science, so take it with a light grain of salt. But a big name in this field is Tim Noakes. Supposedly fat by far isn't as problematic as it was made out to be - lots of money by the powers that be in sugar-land skewed research back in the 1980s to take attention away from sugars as a big culprit. Adding to mmmmmBacon's explanation about lipids vs. adipose tissue, from what I've understood, the idea is that if you eat carbohydrates a lot, sugar will go into your blood, you get these sugar spikes which get turned into body fat, which is problematic. By avoiding carbohydrates and focussing only on lipids in food, your body will learn to process those into the energy it leads, making for a much more even flow of energy leading to less getting permanently stored on your body."
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74tl15 | Why are tuning forks...fork shaped? | There are lots of objects you can hit and produce a tone with. And many of those objects can have their size/shape changed to produce a different sound. Why is a two pronged forked the preferred shape? | Physics | explainlikeimfive | {
"a_id": [
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"text": [
"I'm not sure I can ELI5, but the TL;DR is: \"The main reason for using the fork shape is that, unlike many other types of resonators, it produces a very pure tone, with most of the vibrational energy at the fundamental frequency. \" Credit to the [Wikipedia Article] ( URL_0 ) on tuning forks.",
"*\"The reason is in the acoustic properties of the shape - a U-shaped fork produces a much purer tone than other shaped resonators.* *Secondarily, when struck, the fundamental frequency of vibration has the two sides of the fork move alternately towards and away from each other.* *This motion cancels out in the lateral direction at the fork which means holding onto the handle doesn't cause its energy to be transmitted to your hand (which would quickly dampen the vibrations).\"* - [Yuan Gao, Engineer]( URL_0 )"
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74tqr2 | Oftentimes my grandma will tell me eating certain specific combinations of fruits and other foods will enhance sourness or sweetness. Has my grandmother developed a supreme mastery of flavors over the years or is there a trick to this? | Biology | explainlikeimfive | {
"a_id": [
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"text": [
"Good chefs do this. Basically balancing flavors together so it's not all sweet or salty or sour or umami but a mixture of them. But it would still work if they were separate foods. This is the basis for wine pairing. A good BBQ sauce is tangy and sweet and spicy and savory. As an example."
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74ts8s | How do the food industry determine the expiration date on their products? | Other | explainlikeimfive | {
"a_id": [
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"text": [
"Through extensive testing. Second only to clean water, access to a varied and nutritional diet is the number one global priority for health, so it's no wonder that there are thousands of companies devoted to checking, regulating and enforcing health regulations with food. The Canadian Food Inspect Agency has this to say: > Expiration dates are required only on certain foods that have strict compositional and nutritional specifications which might not be met after the expiration date. These dates are calculated after lab testing. They investigate the specific nutritional values in different scenarios (unopened, opened, left in different temperatures, etc) and determine when food crosses a treshold where these values are too low. This is still a rough estimate, but a very precise one that should never be off by a few hours. Food also does not always have an \"expiration\" date, but rather a \"best-by\" date or \"sell by\". These are broader guidelines; these products are not bought for their 'strict compositional and nutritional specifications', but do have loss of quality after this date. Think of potato chips that lose their crunch, but their salt and starch remains the same.",
"Not in the food processing industry, but I'm a cook. Truth is we can never exactly tell, it's just the estimated time when bacteria and other nasty stuff start to grow past a point past acceptance. When received in a commercial kitchen, we just write the date it was received, and then 7 days after opening is when you throw it out, as per Servsafe requirements."
],
"score": [
22,
6
],
"text_urls": [
[],
[]
]
} | [
"url"
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"url"
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|
74tugn | How do Doctors keep up to date with new information/techniques? | Biology | explainlikeimfive | {
"a_id": [
"do12k0k"
],
"text": [
"They are required to recertify every now and then, as well as being mandated to attend seminars and conferences about the latest of medical science in their fields. Also, a doctor in a specific field is likely to want to learn about improvements in their field. They're clearly interested in whatever field they spent so much time studying."
],
"score": [
8
],
"text_urls": [
[]
]
} | [
"url"
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"url"
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|
74u6x8 | Could I get a cold in a sterile environment? | Biology | explainlikeimfive | {
"a_id": [
"do167e9",
"do16dlk"
],
"text": [
"If the virus is not present, no you can't. The virus would have to be in there first, or you would have to bring it in with you. Getting a cold has absolutely nothing to do with the temperature you are in, that's a myth. Also a cold is caused by a virus, not bacteria.",
"No for a \"cold\"; yes, for other health conditions. First, colds. A cold is caused by something called a rhinovirus (and ONLY a rhinovirus, not just 'getting cold') , that infects you until your body figures out how to make itself fight back, and then you can never be affected by that specific rhinovirus again. But wait, you get more colds right? So how is that correct? It's because cold-causing rhinovirii (much like influenza or flu) mutate every so often so your body doesn't recognize it any more. It's a DIFFERENT rhinovirus. So in an otherwise sterile environment, there's four scenarios here. You had a cold in the past but you're \"immune\" to any remaining rhinovirus from it. You picked up a rhinovirus just before you entered the box. You'll get a cold, but you wouldn't pick it up after living in the box for a few weeks so it'll be the last one you get. You have a cold now. You catch a cold from a new rhinovirus that mutated in your body from an old one left over from your last cold. And this MIGHT be possible but the odds of this happening are so very very small that let's consider it impossible. ---- All this, and you can still get sick. How? Well, being cold all the time is stressful on you and your body has to devote its resources to fighting it rather than keeping all the OTHER bacteria and virii at bay that are normally in your body. And you're probably not sleeping well either, which makes it worse. You won't get a cold, but you might develop heart or other problems or a cut on your skin might become infected more easily from the reduced immune system effects of the constant stress on your body."
],
"score": [
18,
4
],
"text_urls": [
[],
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} | [
"url"
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"url"
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|
74u7vh | how can you determine if a potentially valuable signature is authentic? | Other | explainlikeimfive | {
"a_id": [
"do14ijr"
],
"text": [
"I'm not able to do this personally, but on TV when I see people do it they check out the ink to confirm it's not written in sharpie if the person lived in the 1800s lol then they just look at other signatures they have on file or online and compare the 2."
],
"score": [
3
],
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} | [
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