q_id
stringlengths 6
6
| title
stringlengths 3
299
| selftext
stringlengths 0
4.44k
| category
stringclasses 12
values | subreddit
stringclasses 1
value | answers
dict | title_urls
listlengths 1
1
| selftext_urls
listlengths 1
1
|
|---|---|---|---|---|---|---|---|
7g4ir0 | What direct effects does testosterone have on the male mind and body? | How does it effect your daily life? | Biology | explainlikeimfive | {
"a_id": [
"dqgi42o",
"dqgk4bb",
"dqgkgwc",
"dqgltig"
],
"text": [
"This question has two parts to it, depending on how you phrase it. You can ask how testosterone affects the male mind and body during development, and you can also ask how testosterone affects the male mind and body behaviorally. I'm going to answer the 2nd one, but if you're curious I can also do the first. Testosterone has a lot of interesting implications in parental behavior In general, in the first month of fatherhood, men experience a huge decrease in testosterone, and fathers in general also have lower testosterone than non-fathers. Fathers with more testosterone also tend to be less caring than those with less testosterone. That is to say, fathers with higher testosterone tend to touch and look at their babies less, and use less \"motherese\". So one effect of testosterone seems to be that it impairs direct caregiving. However, fathers have sharp testosterone spikes when hearing their infants cry, so testosterone also seems to have a role in protection. Testosterone also seems to play a crucial role in aggression. Male monkeys tend to have more rough and tumble play than female monkeys, and exposing female fetuses in utero to androgens (a class of molecule that testosterone belongs to) increases their rates of rough and tumble play. Blocking androgen receptors in males will decrease their rates of rough and tumble play. During mating season, where males have to fight each other for mates, many monkey species experience a surge in testosterone. Higher testosterone monkeys tend to be more aggressive, and injections of testosterone produce aggression in monkeys. In humans, criminals who commit violent crimes tend to have higher testosterone levels than those who commit non-violent crimes. Another cool thing to consider is the Ultimatum Game. In the ultimatum game, the first player receives X amount of money, and can choose to give any amount they wish to the 2nd player. If the 2nd player accepts the offer, then they both receive the money, but if the 2nd player rejects the offer, then neither get any money. So, for example, if the first player gets 40 dollars and offers the 2nd player 20 dollars, if the 2nd player accepts, both get 20 dollars but if the 2nd player rejects, both get nothing. Now suppose that the first player only offered the 2nd player 10 dollars, or 5 dollars. It's still in the 2nd player's best interest to accept, since they earn a small amount of money instead of no money, but men with higher testosterone tend to reject more. This is another example of how higher testosterone can lead to more aggression. One reason that this could work is because there are androgen receptors in the medial orbital frontal cortex of the human brain, and testosterone inhibits MOFC activity. The MOFC is the emotional regulation centre of the brain. Testosterone also plays a big role in male sexual behavior. Testosterone influences the development of \"male\" characteristics. It makes men have more angular faces, have more forward protruding eyebrow ridges and central faces, and gives them a more pronounced jawline. Removing testes from monkeys will kill male sexual behavior, but injections of testosterone back will restore it. However, In studies with mice, the medial preoptic area of the hypothalamus has a large density of androgen receptors. Lesioning this area of the brain will kill male sexual behavior, and no injections of testosterone will restore it. This implies that one crucial part of male sexual behavior is testosterone binding to the MPOA. Additionally, in humans, when men have higher testosterone, they tend to find more feminine faces more attractive. This is because females with more feminine faces tend to have higher estrogen levels, which is a sign of fertility. Unsurprisingly, higher testosterone levels also signal an increase in fertility. Reading over this its kind of just a bunch of rambling studies, and I'm sorry about that, but tl;dr Sex and Aggression Edit: If you want me to elaborate on any of this I can",
"> daily life every morning i have to scrape a blade across my face to get rid of the hair that grew the day before. when i put my muscles under stress, they grow larger and stronger quickly. when i'm challenged in a social or work environment, i experience the urge to respond with aggression or violence. this has been going on my entire adult life, so it's easy to keep this under control. it's there when i need it, though. when i see a pretty woman, i get a hit of energy and am suddenly more conscious of my posture and bearing. i get the urge to be nice to her and come on to her. this has also been going on my entire adult life, so it's easy to respond appropriately. i enjoy taking risks. it's fun. this, you may have guessed, has been going on my entire adult life, so it's easy to take calculated ones and not stupid ones. i channel this behavioral urge into positive activities like volunteer fire fighting and approaching strangers in my job and social life. overall, i wouldn't trade that particular hormone for anything.",
"I'm probably one of the best people to ask since I've had both low testosterone and relatively high (on hormone replacement). During my adult life with low T, I would give up on things easily. I'd get very frustrated if I couldn't figure stuff out and would throw my tools on the ground and huff and puff. When my sports team would lose, I'd become very distressed; for days! I had difficulty holding relationships with guys and girls due to my emotional instability. Now that my levels are in the normal range I keep going when I have problems, I have the drive to succeed, and I don't hold grudges, when my sports team loses I get over it within an hour and move on, and much more emotionally stable. I have a much bigger desire for competition and winning, which I get into more now. I'm able to speak my mind when something is bothering me, my communication is better. I also am able to look further into my future to plan ahead, which is nice. People talk about \"anger\", but that doesn't really happen until people are at 3x normal testosterone levels, which only happens in r/steroids, but even they don't seem to have this issue as much as it's stigmatised to be. Usually people report that when they're antagonized, it's easier for them to brush it off and not worry about it rather than want to be in a fight. As for body, testosterone plays a crucial role for bone strength, red blood cell count, and of course, sexual wellness.",
"I wonder if this question is related to this recent TIL thread... URL_0"
],
"score": [
132,
15,
14,
5
],
"text_urls": [
[],
[],
[],
[
"https://www.reddit.com/r/todayilearned/comments/7g2cqb/til_when_men_dont_masturbate_for_7_days_their/"
]
]
} | [
"url"
] | [
"url"
] |
7g4kpv | How can you drink water in countries with temperature less than 0°C ? | Chemistry | explainlikeimfive | {
"a_id": [
"dqgevp3"
],
"text": [
"The water pipes are buried below the frost line for the area. The frost line is the depth to which the ground is expected to freeze during winter. Water pipes go below that, so they don't freeze. The frost line can be more than 4 feet deep in some areas. [Here is a map]( URL_0 )."
],
"score": [
15
],
"text_urls": [
[
"http://4.bp.blogspot.com/-pXa_s_tnpL8/UMY24-2daoI/AAAAAAAABJY/Lx47LTFlMjA/s640/frost-usa-map.gif"
]
]
} | [
"url"
] | [
"url"
] |
|
7g4w4a | If your vehicle is titled and licensed in the same state, then why do license plates expire? | Other | explainlikeimfive | {
"a_id": [
"dqghcjx"
],
"text": [
"Depending on the state, the expiration date on license plate is a function of taxes and registration fees for that vehicle. A new expiration date is issued when those fees are paid."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7g55cg | Why do so many lottery winners end up broke? | Other | explainlikeimfive | {
"a_id": [
"dqgjotf",
"dqgjrj3",
"dqgkhe4",
"dqgjuao",
"dqgkaup"
],
"text": [
"Many lottery winners don't understand how to manage large sums of money, and don't realize how little large sounding numbers actually are. A $1 million prize paid over 20 years is just $50k per year, and that's before taxes on it. So they net about $30k a year, which is more like a nice raise at their job than a shift in lifestyle. But people hear $1 MILLION and they think yachts, mansions, fancy cars, and so on. Even at higher prize levels, they don't realize how quickly those expenses add up and how much the carrying costs are on things like boats and large houses -- you don't just buy the item itself, but also the fees to dock, store, fuel and insure a boat; or pay for utilities, pool/lawn care, maintenance, property taxes, etc. on a house. And then there are all the \"friends\" and family who come out of the woodwork wanting you to invest in their restaurant or business, their can't-miss investment they've discovered, and so on. If the lottery winner can't say no to investments that are bad ideas, they're going to lose the money.",
"In a nutshell, it's because they don't invest it. They blow it on crap they want, depreciating assets.",
"Have you ever worked in a grocery store or gas station? You'll quickly realize that folks that regularly buy lottery tickets are bad with money and are possible gambling addicts. Many are on public assistance. Many are alcoholics or drug addicts that turn to the lottery for a glimmer of hope. The lottery *exploits* these people. Then they'll buy things they can't perpetually afford - like a big house with large monthly property taxes. They'll rack-up debt and'll need to sell the very house they bought to make payments. Many literally *gamble* it away. Many simply just don't know or understand the benefits of hiring a lawyer/estate planner/accountant. They wouldn't know to turn to these resources because they never had to in the past. Sometimes they invest all their money in a business. Given the type of person that regularly plays, you can imagine how this goes. Many go public with a televised appearance - either for recognition or because they're legally required to (in some states). That brings out bottomfeeders - friends or relatives who emotionally blackmail the recipient. Winners also tend to take the lump sum rather than the annuity. Unless you're old, this is dumb. The lump sum is far less money than advertised since prized winnings are highly taxed. The annuity generates less taxes - and creates a framework for reasonable spending (it's easier to budget $100,000/year for 10 years rather than $1,000,000 at once) The winners that don't go broke are either seniors, or those office workers you see pool together for some powerballs for fun.",
"Who plays the lottery the most? Generally, it's people without very much money. People who've had no experience managing larger than a few weeks worth of money. All of a sudden, they have what feels like infinite money, and they spend it like it'll never end. Combine that with all of the \"friends\" and \"relatives\" that come out of the woods asking for money or \"investments,\" and it's the perfect storm to spend too much.",
"Simple; they have the money and spending habbits of a rich person but lack the cash flow of a rich person. All those cars, houses, jewelry, lavish spending and showing off to friends/family adds up as the coins from that pot of gold slowly disappears and now they're sinking deeper and deeper into that pot. In this situation, a rich person with a cash flow will simply refill that pot and stay a float, but lottery winners (the ones who aren't finacially responsible) don't have a stable income big enough to refill what goes out (I'd bet that many of them will call their boss the second they found out they won and told their boss to go screw themself). Things like houses and cars have ongoing costs that people don't think about and when you can't afford it, it's gone."
],
"score": [
41,
11,
9,
4,
4
],
"text_urls": [
[],
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7g5ehr | is there a chemical reason we don’t make banana jam or jelly? Or is it just some weird flavour preference that the whole world seems to share? | Other | explainlikeimfive | {
"a_id": [
"dqgprga",
"dqgnsvs",
"dqgm09y",
"dqgm4ir",
"dqgpht0",
"dqgoix1"
],
"text": [
"Home canner here. Yes, there is a chemical reason we don't make all that much banana jam/jelly. Not by itself, anyway. Without getting into too much detail, there are two basic canning methods: water baths and pressure canning. Water baths basically just immerse jars in boiling water for a while, long enough so that the entire contents of the jar reach the boiling point. Pressure canning actually gets the temperature *much* higher, which you can accomplish with pressure vessels but not with regular pots. Problem: water bath canning doesn't work for all kinds of food. It only works with foods that have at least a certain level of acidity. Many fruits (including tomatoes) are high-acid, and so can be canned using a water bath. But pretty much all vegetables, not to mention meat, fish, and poultry, are all low acid. To safely can low-acid foods, you either need to use pressure canning or add something to the food to raise the acidity. Example: the recipe linked by /u/onions_can_be_sweet includes lemon or lime juice. The citric acid in the juice should be enough to do the trick and permit water bath canning. But now it's arguably not just \"banana jam\". It's \"banana-lime jam\" or \"banana-lemon jam\" or whatever. So, why not just pressure can it? Well, two reasons. First, it is highly inadvisable to can *anything* that hasn't been scientifically tested to be safe. And nobody has done the testing to figure out whether and if so under what conditions bananas are safe to pressure can. But second--and I'm going out on a limb a little on this one--it may simply be that bananas don't take to the high temperatures of pressure canning all that well. Not everything does. The trick about the scientific testing is to find a minimum set of standard conditions that produce safe canned food *that people still want to eat*. Stick anything in a pressure canner for two hours and yeah, I can pretty much guarantee it'll be safe to eat. But that doesn't mean it'd be tasty. I have a sneaking suspicion that running bananas through a pressure canner long enough to ensure food safety would simultaneously render them highly distasteful, if not outright inedible. For what it's worth, this is why you don't see much in the way of canned pumpkin or squash. It's possible to do this commercially, but for the home canner, there's no safe way of canning those foods that results in something anyone would want to eat. For those foods it has to do with how thick they are when you mash them. Proper canning depends upon liquid circulating throughout the jar to ensure uniform temperature and eliminating pockets where bacteria might hide. Squash puree is so thick (and squash lumps so solid) that that doesn't happen. But unlike meats, which are perfectly edible even after extended periods of pressure canning (though they do take on a distinct \"canned\" flavor due to basically overcooking them), pumpkin/squash isn't. No one has found any safe and reliable way to can them at home with an acceptable level of quality. Much the same goes for dairy products. Just. Doesn't. Work. All of the above aside, there's probably a more basic, historical reason we don't see more canned bananas: they're a relatively recent grocery item. Until the invention of refrigeration, it wasn't really possible to export bananas from the Caribbean to the US. Not on any kind of commercial scale, anyway. So by the time bananas became staples in American grocery stores, refrigeration technology rendered home canning largely obsolete. It's still done by a relatively small number of people as a hobby, but you don't see large numbers of people depending on home canning as a major food source the way you did a century ago. So the period of time in which home canning was a widespread phenomenon (something like 1830 to 1950) and the period of time in which bananas were readily available in the US (maybe 1930 onward) don't really overlap all that much. Certainly not long enough for a culture to have developed around canned bananas.",
"Jams and jellies didn’t come out of taste preference. They were invented so people could enjoy that fruit year round. Since Bananas are good all year people never preserved them, and therefore, never became a type of jam or jelly.",
"Not sure who \"we\" is. I make a lot of jam, never made banana jam yet but I've found a number of recipes ([here's one from some random mommy blog]( URL_0 )). I will likely make some one day when I'm bored. I agree you don't see a lot of banana jam in stores, at least where I live (Canada). Maybe that's because good bananas are available all year, they don't seem to have a season, and jam making was traditionally a way to preserve fruit so that it doesn't rot and can be enjoyed out-of-season. I can't think of any chemical or culinary reason why you don't see a lot of banana jam.",
"Bananas are, in many places, the very cheapest fruit by weight -- and they ship well and are available all the time. So there's just not much reason to preserve them in a jar.",
"I think it also has something to do with not being able to juice bananas easily. And since there's little to no juice in bananas, you can't really make a jam or jelly with them.",
"Not sure if it is a chemical or culinary reason, but my mom makes strawberry banana jam and we have to eat it before the others because it gets a weird consistency after about a year. It turns a darker color and gets watery. It still tastes the same though, its just the texture that changes."
],
"score": [
344,
67,
14,
9,
4,
4
],
"text_urls": [
[],
[],
[
"https://confessionsofanover-workedmom.com/how-to-make-banana-jam/"
],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7g5gp9 | What is the difference between Visa, MasterCard, Discover, and Amex, | I work at a certain fast food chain and when a customer pays with a credit card, it prints out a kind of credit card (Visa, Mastercard, or Discover. We don’t accept Amex). I have seen debot cards be both Visa and Mastercard. And at one point I thought Mastercard belonged to only certain credit cards. Also Amex and and Discover arent accepted in certain places and I was wondering why? | Other | explainlikeimfive | {
"a_id": [
"dqgm2lg",
"dqgmdg0"
],
"text": [
"The first two are networks in which thousands of banks cooperate. The second two are individual companies running their own systems.",
"amex and discover have higher fees to the merchant. with visa and MC, the bank and the processor take about a total of 2% out of the transaction as fee. discover takes about same, but amex takes 2.5-3.5% out."
],
"score": [
9,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
7g5hap | How many color combinations are possible with choosing 4 out of 7 colors if colors can be repeated and which formula is applied in this instance? | Mathematics | explainlikeimfive | {
"a_id": [
"dqgofpx"
],
"text": [
"7^^4 = **2041** of possible combinations Someone correct me if I'm wrong, but this should be it E: Wrong, it's **35**, see below"
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7g5yyw | Why do you not cry from onions while wearing contacts? | Biology | explainlikeimfive | {
"a_id": [
"dqgq3r8"
],
"text": [
"The crying from onions is due to the chemicals released in the cutting process getting mixed with the fluid on your eye and creating an irritating acid your eye attempts to flush out with tears. When wearing contacts, they reduce the exposed surface area that the chemicals can interact with, particularly much of the sensitive cornea."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7g5z29 | Teacher just said that when gravity is the only acting force, an elephant and a feather would fall at the same speed. | This makes no sense, as an elephant has greater mass, and therefore a greater pull towards the earth. | Physics | explainlikeimfive | {
"a_id": [
"dqgqaag",
"dqgq6pf",
"dqgpxwe",
"dqgq5ga",
"dqgqjil",
"dqgsvsd",
"dqgpy6d",
"dqgsv0a"
],
"text": [
"Think of the elephant as a million feathers tied together. A million feathers don't fall faster than one feather, whether they are tied together or not. (If you ignore the effect of the air, which is of course huge.)",
"> ...when gravity is the *only acting force*... If you did this on Earth, gravity wouldn't be the only acting force. Air resistance plays a huge role in how fast something falls, and that is what causes the feather to fall much more slowly. Somewhere with no air, they would fall at the same speed. Not nearly the same; exactly the same. > ...as an elephant has greater mass, and therefore a greater pull towards the earth. You said it right there: the elephant feels a larger force from gravity than the feather, but an elephant is also that much heavier. The result is that they will *accelerate* at the same rate, despite the elephant involving more mass and more force. You can google a fantastic little video of an astronaut on the Moon dropping a feather and a hammer. It's neat to see this actually happen.",
"> This makes no sense, as an elephant has greater mass, and therefore a greater pull towards the earth. But the elephant also has more ~~momentum~~ inertia, a greater resistance to change in its movement. It turns out that having more mass makes it more difficult for objects to move at exactly the same rate as it increases their gravitational attraction, exactly canceling each other out. Edit: Here is another way to think about it. Imagine you just have one atom which is falling into a gravitational field. It will fall at a certain rate. Now imagine that you have a second identical atom next to it, not attached, just by its side. Clearly that atom should also fall at the same rate. Now imagine that you stick those two atoms together. Why should they fall any faster than they did when unattached? Each atom would need to be pulled along by the other but there is no reason for either atom to fall faster! Massive objects are just bigger clumps of individual atoms so now it should be clear why an elephant wouldn't fall any faster than a feather when just considering gravity.",
"The more massive something is, the harder it is to change its velocity. An elephant has more mass than a feather, so it takes more force to move it. More specifically, earth's gravitational force is equal to F=mg, where m is the object's mass and g is earth's gravitational constant. Newton's second law of motion says that F=ma, where F is the sum of forces that act on the object, a is the object's acceleration and m is the object's mass. So in this case, ma=mg, and the mass cancels out, resulting in a=g.",
"Your teacher is (approximately) correct. The speed of a falling object in a free fall is independent of object mass, excluding air resistance. Air resistance is specifically excluded, so we won't have to worry about that, and your teacher is correct, in practice. In theory, the object falling also imparts a gravitational pull towards the Earth, and the gravitational force is dependent on the mass of the pulling object, so the elephant would impart a greater pull on Earth, but due to the minimal size of an elephant in relation to a planet, this difference is practically non-existent. Note that realistically air resistance affects this, but it was specifically excluded. This was first proven (well, proven so that we have record of it) by Galileo Galilei. He dropped balls of same material but different masses from the tower of Pisa and found that they hit the ground at the same time. This can also be observed in space: there was an experiment made on the Moon with a feather and hammer being dropped. Moon has no atmosphere, so there is no air resistance, and they did hit the surface at the same time, proving that Galileo, and your teacher, are correct.",
"In vacuum they would fall at the same speed, but not on Earth due to air resistance. NASA did an experiment on the moon where they droped a feather and a hammer at the same time and they hit the surface of the moon at the same time. Think there's a video om YouTube of it",
"The speed is dictated only by the acceleration, which is the same for both (g). The mass has not effect on speed. In reality the feather falls more slowly because of air friction.",
"The acceleration due to gravity is not dependent on mass. From the same height and from a complete standstill, very object falls at the same rate, if there is no other force acting on them (wind resistance). [You can watch a test on the moon]( URL_0 ) where a feather and hammer are dropped, and without the atmospheric resistance to slow the feather, you can see that they fall at the same speed."
],
"score": [
71,
39,
14,
6,
5,
4,
3,
3
],
"text_urls": [
[],
[],
[],
[],
[],
[],
[],
[
"https://youtu.be/5C5_dOEyAfk"
]
]
} | [
"url"
] | [
"url"
] |
7g60tp | Why does the brain control body functions contralaterally, and is this true of all species? | Biology | explainlikeimfive | {
"a_id": [
"dqhe394"
],
"text": [
"It has to do with our nerves! Our nerves cross on their way from the brain down to the effectors (muscles, glands, etc.). There are actually a few theories as to why the nerves cross (or \"decussate\") to the other side of the body. The one we learned about in my neuroscience class was that basically when we went from 4-legged to 2-legged in an evolutionary sense, some of the components of our nervous system 'twisted' a bit with the change. There are a few other structures in the central nervous system (CNS) that have a twist like this too (although the names of said structures are escaping me at the moment!). This is true for vertebrates but not invertebrates. I'm a master's level health profession student so hopefully I have this correct! If not, I have more studying to do for finals... EDIT: I'm also baked."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7g62hv | How can drinking water stay clean when it is travelling through old pipes? | Other | explainlikeimfive | {
"a_id": [
"dqgrvf8",
"dqgssuv"
],
"text": [
"I would assume that the constant flow of fast water prevents bacteria, fungus, and other life from being able to settle on the walls of the pipes to grow. Probably the same concept as using a pressure washer to clean stuff. Much like stagnant water is bad to drink from, but fast flowing water is more safe to drink from (When backpacking in the wilderness away from cities). I do know that there are chemicals added in safe amounts to help prevent bacteria from growing at the water treatment plants. Not an expert on the subject, but have a feeling this is correct.",
"A 100 yr old pipe and a pipe installed yesterday both will have the same scale buildup inside. The water is not in contact with the actual pipe."
],
"score": [
18,
6
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7g6bky | How do Emulators like Dolphin make old GameCube games look almost like they are in 4K? | Basically what i'm asking is why does Super Mario Sunshine look blurry and terrible on it's native resolution but the water looks Crystal clear and amazing on the highest settings if the game was never intended to be seen that way? | Technology | explainlikeimfive | {
"a_id": [
"dqgu3pe"
],
"text": [
"The output of the gamecube was limited to the displays they knew they were going to use back then. I think the Gamecube's max output was 480p which is basically 640x480, because most TVs couldn't display any more detail than that. An emulator doesn't have those limitations. It has much more power to throw at the problem, and it has much higher output resolution, so it can take the original game code and render the output at greater resolutions, to truly from the ground up, increase the 3D detail. There's no way to improve the textures, but some things will gain a lot of definition by doing it."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7g6btr | If microwaves heat food by vibrating water molecules, then why do some ceramic bowls get 10 times hotter than the food they hold when they have no moisture inside them at all? | Chemistry | explainlikeimfive | {
"a_id": [
"dqgsvvw",
"dqgwynd"
],
"text": [
"microwaves heat food by shooting microwaves at it. Water absorbs those microwaves, vibrates and heats up. Thats not to say nothing else absorbs it, certain ceramics do as well. Its actually part of which products are microwave safe and which aren't (along with usually BPA content).",
"Microwaves, the waves themselves, have a width and oscillate. This causes polar molecules below certain sizes to oscillate with them. Water happens to be a properly sized polar molecule, but it is not the only one which experiences the oscillation. So depending on the composition of you're dish, there may be other molecules affected by the microwaves. Hope this helps."
],
"score": [
12,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7g6fje | I love to take naps but why do you usually feel terrible after one? | Biology | explainlikeimfive | {
"a_id": [
"dqgtoai",
"dqgtun1"
],
"text": [
"I never feel terrible after a nap. You might be sleeping too long. If you nap too long, you can get into a deep sleep cycle. If you’re forced to wake up before you come out of that, say by an alarm or noises in the area in which you are napping, you’re going to feel terrible because you got pulled out of deep sleep. For me, a nap is 30 minutes. Longer than that, and I have to go about 90 so that I have time to get into and back out of a deep sleep.",
"For most people sleeping in either 30 or 90 minute intervals is optimal; 30 minutes is right about when you start to go into deep sleep phases, and 90 minutes should be right after a full REM phase and in a light sleep phase. Hour-long naps will probably end up with you awake in the middle of a deep sleep phase."
],
"score": [
10,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7g6hhl | Why do we need to wear so many layers on our body when it's cold, but only one layer of pants? | Is it because of our organs or something else? | Biology | explainlikeimfive | {
"a_id": [
"dqgwotz"
],
"text": [
"Yes, keeping your \"core\" warm is more efficient in terms of amount of clothing than insulating your extremities. Your body can transfer heat from the torso to legs and feet. However, this only works for people going between heated rooms, like from your house, to your car, to your office. For anyone that needs to in the cold for longer than half an hour, more layers are absolutely necessary. Ask any security guard, construction worker, etc. Not sure about other branches, but in the Army we wore standard tights, beneath thicker tights, under our trousers. That's three layers for our legs and it's only for regular winter climates. It's certainly going to be more layers for colder places like Alaska or New England."
],
"score": [
12
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7g6lg2 | If working out muscles makes them stronger, and your heart is a muscle. Why does caffiene and things that increase heart rate not "work out" your heart and make it stronger? | Biology | explainlikeimfive | {
"a_id": [
"dqgvhnx",
"dqgzzua",
"dqgvmfj"
],
"text": [
"The heart has a unique role among all the muscles of the body. It is the only muscle that works all the time. The heart never stops beating, from birth until death. As a result, the main danger to the heart is over-exertion, rather than a lack of exercise. In the case of the heart, it is literally impossible for it to lack exercise. But it is possible for the heart to suffer excessive stress.",
"Strengthening the heart means pushing more blood per beat aka increasing blood flow. Stimulants don’t do that because there’s no need for this extra blood. It’s like if you have your engine at idle and you rev it vs having a load in it and revving it. When the engine at idle is revved higher than it needs to be, it’s just wasteful.",
"When you work out your muscles, they don't get more powerful unless you're lifting weights heavy enough to push their limits. The heart is much the same way. Imagine the chambers in your heart that contract with each beat. Between beats, blood flows into these chambers and stretches them out. The more stretched the chamber is due to blood, the more force it must use to shove a healthy fraction of that blood out. When you're not exerting yourself, the chambers don't fill up enough for your heart to grow stronger. During exercise, your body's oxygen demands go way up, and blood flow increases quite a bit. This means more filling of the heart, and more force of contraction. Things like caffeine can affect your blood pressure enough to increase filling (what we call \"stroke volume,\") but not to a substantial degree. These substances usually just make the heart beat faster, which means it's actually pumping smaller volumes with each stroke."
],
"score": [
12,
3,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7g6vw0 | How does the Plan B pill work? | I know that it basically is a large amount of a birth control hormone, but what does it physically do in the event that a sperm has made contact with an egg? | Biology | explainlikeimfive | {
"a_id": [
"dqgxsvm"
],
"text": [
"The plan B pill is a very high dose of a hormone similar to progesterone. When you take it, it prevents any eggs from being released, just like for daily birth control pills. Pregnancy causes a large increase in progesterone, and this increase in progesterone stops the menstrual cycle in one spot, meaning no eggs are released for the duration. Increasing progesterone temporarily with plan B works to stop ovulation for long enough that fertilization doesn't happen. This works because the common notion that immediately after ejaculation the sperm all have a race to the egg is not realistic. It really does not work like that. What usually happens is that the egg hasn't been released at the time of sex (family planning by having sex when it is likely to be released is one way of increasing the odds of becoming pregnant). The sperm just sort of hang out inside the uterus along the walls, waiting for the egg to drift by. They can survive like that for a few days, I believe, and if no egg is released in that time, pregnancy will not occur. As far as I know, they are ineffective once the egg has been fertilized. That's a common misconception. Different hormones are used to induce abortions by causing menstruation to happen. [More info]( URL_0 )"
],
"score": [
10
],
"text_urls": [
[
"http://ec.princeton.edu/questions/ecwork.html"
]
]
} | [
"url"
] | [
"url"
] |
7g6x1d | Why is it so hard to count how many zeroes are in the following number "8000000000091" without losing my place | Biology | explainlikeimfive | {
"a_id": [
"dqh86mf"
],
"text": [
"Humans can only really [subitize]( URL_0 ) groups of up to four items at once. This is the maximum number where we are able to immediately look at a group of objects and tell how many there are accurately. The speed, and then also accuracy drops off rapidly with larger groups. Different brain processes are used; with slightly larger groups we tend to have to consciously count and also make more mistakes. This is a big motivation of why we have number separators like the comma and period, and also in the design of the abacus."
],
"score": [
9
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/Subitizing"
]
]
} | [
"url"
] | [
"url"
] |
|
7g6x63 | Why are speakers capable of reaching volumes that can break the speakers? | Technology | explainlikeimfive | {
"a_id": [
"dqgxzp4"
],
"text": [
"That's a bit of an odd question. A speaker is an entirely passive device, it just creates a sound based on the electrical signal that's going into it. If you put more power into it than it's rated for, it's going to go bang. It's like an electric motor. They'll be designed for a certain rate of speed at a certain power level. If you have a power source that can put more power into it, it'll spin faster and faster until it fails. That's not a fault of the motor. Why don't they put protective circuits into these things to stop it happening? If that's what you're asking it's a simple matter of cost. For something most people wouldn't ever need, it'd be an extra expense, so the manufacturers are pragmatic and don't include it. Even if they did though, if you overdid it enough, the devices would still fail."
],
"score": [
10
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7g720z | How does muscle enable us to lift heavier things? | Obviously bigger muscles tend to lead to stronger people able to hold heavier objects. But what about muscles actually enables humans to lift heavier objects? | Biology | explainlikeimfive | {
"a_id": [
"dqgzkcr"
],
"text": [
"Muscles are made of fibres which contract to make a certain action. For example, a bicep curl. The more muscle, the more fibres. The more fibres you have contracting together, the more force you create. More force allows you to lift more."
],
"score": [
17
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7g74bn | what pushes our wisdom teeth to come out so late? | Biology | explainlikeimfive | {
"a_id": [
"dqh2mfr"
],
"text": [
"The wisdom teeth were useful when people chewed on hard food and lost their teeth. They don't come out too soon or else they would disrupt the other teeth (which is what happens now, now that our teeth hygiene is very high) from growing correctly. And they don't come out too late, because you might be dead. Or you would get used to your teeth."
],
"score": [
8
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7g78nw | Why does spinning in circles make you sick/nauseous? | Biology | explainlikeimfive | {
"a_id": [
"dqh0jsq",
"dqh0w9h"
],
"text": [
"Your ear contains three tubes filled with liquid and tiny hairs. When you change orientation, this liquid moved around and hits the hairs, signaling your brain. This is your sense of balance. When you spin around the liquid starts whirling and doesn't stop, even when you do, just like when you stir water in a glass. So your brain thinks your body is moving while it obviously isn't, causing a dissonance.",
"The human body has many sensory systems that detect what is going on within us and around us. Several are located in the inner ear, including those that detect angular and linear acceleration. One such system is basically some tubes that are filled with fluid that helps us orient ourselves and aid us in maintaining balance. When you spin around this fluid will start to spin as well, but if you suddenly stop spinning this fluid will continue to spin within the tubes. Now you have two systems that are in conflict with one another. Your eyes (among other systems) tell you that you are standing still, but the fluid-filled tubes tell you that you are still spinning (angular motion). Your brain has to reconcile these incompatible reports, and one such response to assume that you have been \"poisoned\". A safe response to this conclusion is to vomit (nausea is your body warning you that it plans to vomit), as food is the most likely source of poisoning."
],
"score": [
11,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7g7ut9 | how does the texture of things touched by my fingers tips get transmitted to my brain to give me that feeling of the object | Biology | explainlikeimfive | {
"a_id": [
"dqh6zxc"
],
"text": [
"We have receptors on our body, which are proteins embedded on the surface of cells, responsible for the sensations of touch, of which we will focus on mechanical force, heat transferred, and movement When you touch something, you are establishing a few things 1) the shape and smoothness of the object around the point of contact is determined by how many receptors are being activated at once and where on your finger. 2) the amount of force that you're exerting on an object 3) the amount that your fingers have moved after exerting that much force (tells you have pliable or soft the material is) 4) how much heat the object gives off When you put together the signals, your brain interprets it as some sort of texture."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7g83wt | Why is it easier to whistle with wet lips? | Biology | explainlikeimfive | {
"a_id": [
"dqh73so"
],
"text": [
"The layer of water smooths the lips, reducing random turbulence that would interfere with the whistling motion of the air."
],
"score": [
8
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7g8a3o | Can you damage the inside of your body if you constantly eat hot food and drink hot beverages? | Biology | explainlikeimfive | {
"a_id": [
"dqh8im1",
"dqh9r3t"
],
"text": [
"If the temperature of the food is high enough to burn your skin outside the body it will do so inside as well. Otherwise food cooling to body temperature isn't really a strain on the body.",
"Hot as in spicy food can cause distress in your GI tract, due to the chemicals irritating the tissues lining it. Otherwise, you should be fine as long as the food isn't hot enough to cause physical damage. If you experience persistent discomfort when eating certain foods, it might not be temperature that is the issue but some other form of irritation. A doctor would probably be able to assist you better."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7g8aik | Why does our body only release antibodies into our bloodstream after being infected? | Biology | explainlikeimfive | {
"a_id": [
"dqh8vds"
],
"text": [
"You do have low levels of most of the antibodies you are capable of producing at all times, and this helps with immunity. It is true that when a remembered pathogen is recognized, antibody production for it specifically kicks into super high gear. A couple reasons it's not in high gear all the time: * It would take huge amounts of energy to make \"high gear\" levels of antibodies against everything you are immune to * It would also probably cause actual physical issues with your blood being too thick with antibodies and antibody-producing cells * You would feel pretty sick all the time-- a lot of the symptoms of sickness are the immune response, not the bacteria/virus itself * You wouldn't be able to devote as many resources to fighting whatever pathogen is actually there, as they would be taken up by fighting pathogens that aren't there"
],
"score": [
11
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7g8kz0 | Why do your armpits smell bad from B.O. but the rest of your body doesn't stink like that? | Biology | explainlikeimfive | {
"a_id": [
"dqhawcf"
],
"text": [
"Few reasons. 1- The smell is from bacteria breaking your sweat down, not the sweat itself. 2- Your armpits and other parts that typically smell bad have hair, which traps oils and sweat, and allows for all those things to stay easily in place for bacteria to digest. 3- There's a couple different types of sweat glands, the ones at your armpits and such secrete different kinds of sweat which contain different substances. Which may be more easily digested by the bacteria, or liked by them more."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7g8r6r | why does the sun appear brighter when rising in the morning than setting at night when at the same height in the sky? | So just wondering why when I go out in the morning the sun rise is blinding but when the sun sets in the evening it is much less bright and has a kind of warm orange hue to it, even though they're perceivably at the same height in the sky? | Physics | explainlikeimfive | {
"a_id": [
"dqhdxru"
],
"text": [
"When it's dark your pupils dilate to see better in low light conditions. As the sun comes up your eyes are constantly adjusting to the now brighter world, meaning that you experience a brighter sun because you have not yet adjusted, always playing catch up. At night this process is reversed. Your eyes constantly adapting to a darkened world, always playing catch up."
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7g8shk | Why when it’s dark can I sometimes see things better by not looking directly at them? | Biology | explainlikeimfive | {
"a_id": [
"dqhcgit"
],
"text": [
"Your retina has two types of cells for detecting light -- rods and cones. Cones are used to perceive color and fine details, while rods are bad at color and details, yet very sensitive to low levels of light. Those two types of cells aren't evenly distributed in the back of your eye. Since we'd want to have our best HD color vision right where we're looking, that area is packed with tons of cones. All around that are large amounts of rods. This means that when you're trying to see in the dark, it's actually best to not look at things right where the cones are, which is in the middle of your vision."
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7g8t0s | Why don’t things like stickers and tape work when they are submerged in water? | Chemistry | explainlikeimfive | {
"a_id": [
"dqhcgst"
],
"text": [
"The adhesives work by contacting and physically or chemically attaching to the surface. Water molecules obstruct that contact on a microscopic level, and may also chemically interact with the adhesive."
],
"score": [
9
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7g9893 | How do parrots say sounds made by the letters B, F, M, or P without lips? | I thought of this last night and it's really getting to me. You have to have lips to pronounce the first syllable of "Polly want a cracker"... How do they do it? | Biology | explainlikeimfive | {
"a_id": [
"dqhfsqu"
],
"text": [
"You can produce these sounds by pressing your tongue against your upper lip too, you don't *need* a set of lips to approximate it, just a way to modulate the airflow properly. Parrots can come pretty close to most human speech with their tongue, beaks, and weird respiratory system setup, but sometimes they have to use a roundabout method of making specific sounds."
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7g9i0p | Why does having someone else scratch my scalp feel so much better than scratching my own? | Biology | explainlikeimfive | {
"a_id": [
"dqhi71u"
],
"text": [
"When you scratch your own scalp, your attention is divided between the act of scratching, and the perception of being scratched. If someone else scratches your scalp, you can devote your entire attention to the sensation of being scratched. It is also true that in evolutionary terms, primates have groomed each other long before the human race even existed. It is a very well established social ritual."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7g9zxm | Why does US restrain from shooting down N.Korean missiles? | Other | explainlikeimfive | {
"a_id": [
"dqhlv76",
"dqhluul",
"dqhlz7c"
],
"text": [
"You can calculate the trajectory of a ballistic missile shortly after launch, and it's clear that the trajectories for these are not aimed at land. Launching a costly intercept system (and showing our exact intercept capabilities and locations) to pick off an annoying but harmless test launch isn't worth the trouble.",
"because theyre never endangering the US and that would be an active act of war, which we're trying to avoid. Starting a war over a missile test is a bad idea",
"There are a couple different reasons. First, missiles are expensive. We can calculate the trajectory of the NK launch quite quickly and why waste $100,000 shooting it down if it will just go into the ocean. Secondly, secrecy. NK has terrible spy networks and likely doesn't know the precise locations of our missile defense sites. Shooting down their rocket would expose those locations to the whole world. Three, provocation. Any step we take will be seen as hostile and we are trying to avoid a war with NK. We would certainly win, but hundreds of thousands of South Koreans would die in the process thanks to conventional artillery pointed at the capital there."
],
"score": [
5,
4,
4
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7ga2p7 | What is the point in providing First and Last months rent if you are signing a contract anyway? | Economics | explainlikeimfive | {
"a_id": [
"dqhmjwn",
"dqhmjox",
"dqhmm4q",
"dqhn0j9"
],
"text": [
"It's pretty easy for people who give no shits to disappear well enough to make it almost impossible for them to collect the money they want. You might also die, declare bankruptcy, or go to prison. And if you aren't a compliant person about paying what you owe, it can be expensive for the rental company to squeeze the money from you using lawyers and court.",
"> To make sure I don't rent one month then disappear? Is it really that much an issue? yes it is It also is a nice lump sum for the renter, along with showing that you can afford to do 2 months at a time, which probably means you can afford the whole year",
"you still owe the money....on paper. money on paper doesn't mean it's in the landlord's pocket. what happens if you decide that you don't want to live there anymore and just move out without telling the landlord and stop contact? he loses out on a month of rent. another month of finding a new tenant. legal costs of pursuing a lawsuit against you. what happens if you decide you don't want to pay rent anymore and squat? landlord loses month of rent. landlord loses another month of giving eviction notice, going to court to get a judge to sign the eviction order, scheduling with the sheriff to come force you out of the house.",
"There are two main reasons. First, if you *can't* get two months for rent together, you probably aren't financially stable enough to afford the rent to begin with. My brothers and I have been landlords, and a few times let someone with a sob story slide by. Every single time it was a mistake and they turned out to be deadbeats. The other big reasons is being owed money is very different than being able to get money. Sometimes they don't pay and disappear with no forwarding address, sometimes they don't pay and stay, evictions can take months. My brother once had a tenant claim he failed to disclose the house was haunted. Not only did she refuse to pay rent, she sued him for the rent she previously paid, moving and hotel expenses. He won in court and was awarded all of his back rent, and after a year has never seen a dime of it. Having a cushion of a month's rent would have softened the blow, except she was one of the aforementioned mistakes."
],
"score": [
6,
5,
4,
3
],
"text_urls": [
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7ga56b | Why can't we move our eyes individually? | Biology | explainlikeimfive | {
"a_id": [
"dqhn58g",
"dqhnh9e"
],
"text": [
"The visual center of the human brain combines the information that it receives from both eyes to form a picture of what you are seeing. If your eyes are not both looking in the same direction at the same thing, you get a confusing effect like a double-exposed photograph. There do exist some species which move their eyes independently, but they have a different way of interpreting visual information.",
"I can. It's hard, but what I normally do is cross my eyes first. This makes it easier to hold one eye in place. Then, with some difficulty, I can look around the room with the other."
],
"score": [
5,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7ga5dw | Why do joints or bones make a pop or click sound? For example my ankles pop a lot. If I rotate my ankle five times in a row it will pop five times in a row. | Biology | explainlikeimfive | {
"a_id": [
"dqhodhz"
],
"text": [
"that cracking or popping noise is the sound of air between your joints escaping rapidly, letting out a loud sound"
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gamwl | Why is some food "aged" and still edible while others are rotten and tossed out? | Basically the title, why do we age some foods (some cheeses, wine, some meats) and it's still edible or even delicious, but other foods are thrown out when they hit two days old? | Biology | explainlikeimfive | {
"a_id": [
"dqhrfnf",
"dqi31cv",
"dqhu3j9",
"dqhxrb0"
],
"text": [
"Rotten food is an uncontrolled explosion of microorganism activity, which is almost always going to produce toxins or at least make the food entirely unpleasant. Aging food is a more controlled process. Conditions such as temperature, humidity, salinity, etc are tuned to allow some bacteria, yeasts, etc to grow and to inhibit others. Somethings are fermented, because we want yeast to turn sugar into alcohol, or other things are aged to become super dry so nothing can grow on it.",
"I can speak to wine and beer. When things ferment with yeast there is an increase in acidity and an increase in alcohol. Both the acidity and alcohol prevent harmful bacteria (e coli, botulism etc...) from being able to survive and reproduce. There is also a strong lack of food (carbohydrates) since the yeast already consumed most or all of it. The end effect is you have a beer/wine that is a fairly toxic environment for other bacteria to survive. High abv, low levels of nutrients, acidic, and also usually devoid of oxygen and instead filled with carbon dioxide. All of those add up to an environment that is bad for bacteria. You can theoretically age a beer or wine indefinitely. It probably wont taste like it did when it was fresh, nor will it probably taste good at all, but it wont kill you. I've heard of people drinking beers from the 80s (thomas hardy's, some lambics, some belgian stuff) that was cellared properly and tasted wonderful. I have also drank wine from the early 2000s that was not cellared properly and tasted horrible.",
"And then there are some that are rotten but still eaten.. [like this cheese for example..]( URL_0 )",
"Because of \"bacteria\" (which can sometimes be mushroom or whatever) Wine is rotten grape juice, Cheese is rotten milk, same for ... The main difference is that you controll the rotting process so you add the right type of bacteria/yeast to the product (thousands of year of history and tradition taught us the right way to do it). And select the product you use (historically you use what your local crop produce). The \"good bacteria\" will take all the available space, letting only few space available for bad bacterias. And transform sugar into alcohol (for wine) or lactose into (that's a good question). The set of bacteria and original product used will affect the final taste of the product and that's why a wine or cheese taste differently depending where they are produced and from which grape/cows comes the product (It's a little bit less true for industrial products)"
],
"score": [
51,
12,
9,
5
],
"text_urls": [
[],
[],
[
"https://en.wikipedia.org/wiki/Casu_marzu"
],
[]
]
} | [
"url"
] | [
"url"
] |
7ganln | Why is it that when a loud noise goes off near me, my body startles before I even hear the noise or realized what just happened? | Biology | explainlikeimfive | {
"a_id": [
"dqhs72t"
],
"text": [
"Your body is a very complicated machine that has a lot of features to help you stay out of trouble! When avoiding something dangerous coming towards you very quickly, like a predator pouncing on you, every millisecond counts. On the other hand, the average time between you consciously perceiving something and acting on it is about 250ms- a quarter of a second. That's enough for a tiger to land on you and start pawing at your soft bits. So your body recognizes some things as dangerous or worthy of attention. When it detects these things, even before they get to your awareness, it triggers automatic responses that get you out of the way of danger. For example, closing your eyes when something flies towards you quickly, or drawing you hand away from pain. Then your conscious mind \"catches up\". Some tidbits of reading: URL_1 URL_0 URL_2"
],
"score": [
13
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/Looming",
"https://en.wikipedia.org/wiki/Startle_response",
"https://en.wikipedia.org/wiki/Muscular_defense"
]
]
} | [
"url"
] | [
"url"
] |
|
7gaxpp | Why is the sound of chewing so much louder when wearing ear phones? | I'm trying to escape the outside distractions by wearing earphones (specifically ear buds.) Why am I hearing the sound of my teeth crunching on salad so much more while wearing them. | Biology | explainlikeimfive | {
"a_id": [
"dqht4ec"
],
"text": [
"Once you cut out the distraction caused by noises in your environment, the noises that you cause internally, inside your own mouth, will be that much easier to hear. Those noises do not have to reach your inner ear by way of your eardrum which is blocked by earphones. They can travel directly by bone conduction, through your skull."
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7gb28s | if your body thinks its eating sugar does it still produce insulin? | i.e. fake sugars | Biology | explainlikeimfive | {
"a_id": [
"dqhwjy2"
],
"text": [
"No. The pancrease only undergoes the steps to raise insulin levels upon a stimulus response of glucose within your bloodstream. If its not glucose in your bloodstream then insulin stays the same."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7gb31c | Why is Netflix's website so fast and slick. I mean the actual site not the streaming videos. The site takes ~2-3 seconds to load 100+ of images, a streaming video and more with almost never a delay. | Technology | explainlikeimfive | {
"a_id": [
"dqhu5c6",
"dqhu763",
"dqhu1po"
],
"text": [
"Quote from a former employee at Netflix: \"Variable data streams, multiple CDNs, buffering, metric-gathering, and because we've been doing this arguably longer than anyone else and have the experience to support a large number of devices and connection speeds.\" (Yan Biao Boey) I guess he's right bc Netflix was founded in 1997",
"There's another factor as well. Advertising supported sites often have the ads \"bid\" for which ad gets shown. To allow time for this to happen, the page load is sometimes delayed as a second or third request needs to be made to another server before the page is displayed. Netflix, on the other hand, hosts all it's stuff itself, so it doesn't need to ask anyone else, thus reducing the delay for a page load.",
"Someone correct me if I'm wrong but, Amazon Cloud Servers hosts Netflix servers. And they are decentralized meaning areas like Houston, Texas or Columbus, Ohio may have its own server farm. This helps in reducing routing between you and them. ELI5- Picture you local postal server if it was 50 miles away your mail would take longer to deliver, but move it within 10 miles and add 5 mail servers to cover that 50 mile radius and it becomes efficient."
],
"score": [
14,
7,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7gb7mv | People claim doctors get kickbacks for prescribing certain brand meds to patients. How can this be true, if patient information is kept confidential? | Other | explainlikeimfive | {
"a_id": [
"dqhzeek",
"dqhvc83"
],
"text": [
"Every time the pharmacy tech puts prescription information into the computer, certain information is automatically added to a database. No patient information is listed, just doctors, prescription names, dates and pill counts. Pharmaceutical companies have access to this database, and thus can tell which doctors are prescribing how much of which medications without violating HIPPA. URL_0",
"Doctors are sometimes bribed or paid large amounts of money from large companies, who make medicine, to sell their particular brand of medicine. Even if many other companies make the same medicine without charging as much to the patient. The big company that sells the medicine doesn't have to know anything about the patient, but they do know which particular doctor is selling more of their brand. Thus, the doctor makes more money, and so does the large company."
],
"score": [
8,
4
],
"text_urls": [
[
"https://youtu.be/YQZ2UeOTO3I"
],
[]
]
} | [
"url"
] | [
"url"
] |
|
7gb82y | What is that lump that forms in the throat when someone is about to cry? Why does it happen just before crying? | Biology | explainlikeimfive | {
"a_id": [
"dqhv360",
"dqhxasz"
],
"text": [
"Explanation The lump-like thing we feel when overcome by emotion has to do with how the nervous system deals with stress. The part of the nervous system that handles stress is called the autonomic nervous system. It controls bodily functions that we do not consciously control, such as digesting food and pumping blood through the heart. However, the autonomic nervous system is also important in dealing with emotional states. When an animal encounters a stressful situation, its autonomic nervous system kicks in to allow it to either fight or run away. It does this by increasing the flow of blood and oxygen to the necessary muscles. The same applies to humans. Even when we experience emotions such as grief or sorrow, the autonomic nervous system responds as it would to anger or fear by increasing the flow of oxygen through the body. Oxygen Intake To increase oxygen intake, the autonomic nervous system makes us breath faster, and expands the glottis, the opening in the throat that allows air to flow from the larynx to the lungs. The expansion of the glottis in and of itself does not create a lumpy feeling, until we try to swallow. Since swallowing involves closing the glottis, this works against the muscles that open the glottis in response to crying. We experience the resulting muscle tension as a lump in the throat. Cheers",
"Yer not alone in askin', and kind strangers have explained: 1. [ELI5: Why do we get a \"lump\" in the throat when we get really emotional? ]( URL_3 ) 1. [ELI5: Why do we feel a lump in our throat when we hear upsetting news? ]( URL_7 ) 1. [ELI5: When you hold back tears, why does your throat hurt? ]( URL_1 ) 1. [ELI5: Why Do We Get a Lump in Our Throats Before We Cry? ]( URL_4 ) 1. [ELI5: Why do I get a lump in my throat when I'm about to cry? ]( URL_5 ) 1. [ELI5: What is the lump in your throat feeling you get when you are sad or mad? ]( URL_0 ) 1. [ELI5: Why do our throats choke up when we feel sad or emotional about something? ]( URL_6 ) 1. [What actually happens when you get a lump in your throat? ]( URL_8 ) 1. [ELI5: Lump in your throat ]( URL_2 )"
],
"score": [
57,
7
],
"text_urls": [
[],
[
"https://www.reddit.com/r/explainlikeimfive/comments/16lpy7/eli5_what_is_the_lump_in_your_throat_feeling_you/",
"https://www.reddit.com/r/explainlikeimfive/comments/22ilon/eli5_when_you_hold_back_tears_why_does_your/",
"https://www.reddit.com/r/explainlikeimfive/comments/3ca1un/eli5_lump_in_your_throat/",
"https://www.reddit.com/r/explainlikeimfive/comments/264yks/eli5_why_do_we_get_a_lump_in_the_throat_when_we/",
"https://www.reddit.com/r/explainlikeimfive/comments/5nbcup/eli5_why_do_we_get_a_lump_in_our_throats_before/",
"https://www.reddit.com/r/explainlikeimfive/comments/1pq1te/eli5_why_do_i_get_a_lump_in_my_throat_when_im/",
"https://www.reddit.com/r/explainlikeimfive/comments/4kgbts/eli5_why_do_our_throats_choke_up_when_we_feel_sad/",
"https://www.reddit.com/r/explainlikeimfive/comments/5rdp0j/eli5_why_do_we_feel_a_lump_in_our_throat_when_we/",
"https://www.reddit.com/r/NoStupidQuestions/comments/6mbams/what_actually_happens_when_you_get_a_lump_in_your/"
]
]
} | [
"url"
] | [
"url"
] |
|
7gb97z | How do people die from a broken heart? | What is the condition exactly, or is it solely emotional? | Biology | explainlikeimfive | {
"a_id": [
"dqhv7el"
],
"text": [
"\"Broken Heart syndrome\" is often a poetic description of a number of different clinical ailments that can result from emotional stress. You're heart does not literally \"break\" due to physical or emotional trauma. That said, over the course of time your heart can undergo much traumatic damage from emotional sources like PTSD, Clinical Depression, Or Psychological trauma to some degree. These diseases can put stress on your cardiovascular system over time, that can contribute to heart health degradation, and eventual failure."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7gbjqn | Why is it when you drive past objects fast with your window down you hear a “whoosh” noise after each object? | When you drive past stationary objects like other parked cars, trees, fire hydrants you head a “whoosh” noise. The fast you go the louder the noise, the slower you go the quieter the noise. But the object isn’t actually making a “noise,” because it’s just there normally. | Physics | explainlikeimfive | {
"a_id": [
"dqhx27c"
],
"text": [
"It's the reverse effect of why you, when stationary, hear a whoosh when something zips by you! The whoosh sound is made from displaced air, the faster the displacement the greater the sound. Sound is caused by motion, after all. Ever heard of a sonic boom? When you break the speed of sound, things get... Loud... At any rate, the whoosh you hear while in motion is the sound bouncing off of the object and coming back to your ears sooner than the rebounding sound wave hitting objects further way and returning to your ear. Basically, this is the easiest way to explain sonar!"
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7gbk9e | What determines penile size? Genetics? Diet? Lifestyle? | Biology | explainlikeimfive | {
"a_id": [
"dqhx4mv"
],
"text": [
"It's mostly genetics, plus some environmental effects. Genetics lays the framework for the \"range\" that your penis size can be. During pregnancy, depending on androgen (testosterone,etc) levels, that can affect the level of final \"masculinity\" of a child. If the baby has a lot of androgen receptors, then when androgen binds, it'll create a larger effect and increases final penis size. So at birth, essentially your \"final penis size is determined\" just not reached. During puberty, your penis enlargens until it reaches the final size determined by genetics and during pregnancy. We can tell its determined mostly at birth, because people with partial androgen insensitivity syndrome can have smaller than normal penis size, or female appearing genitalia. Diet and lifestyle doesn't do anything. Otherwise penis enlargement pills might actually sell instead of being a massive scam. That said, your maximum erect girth can decrease if you've had a recent ejaculation, or something like low testosterone."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gblzf | Why do you only see with one eye when one is closed, why can’t we see the black from the closed eye | Biology | explainlikeimfive | {
"a_id": [
"dqhx5cd",
"dqhx69q"
],
"text": [
"You can, your brain is just really good at ignoring it, just like your nose is always in your vision but it never bothers you because your mind is used to it and doesn't see it as important information.",
"Your brain deletes the useless information in order to construct the most useful visual image it can. Same reason you don't see your nose most of the time. Same reason you don't see the room jumping around when your eye makes hundreds of tiny motions."
],
"score": [
7,
4
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7gbo9p | How can it be sunny but cold and cloudy but warm? | Physics | explainlikeimfive | {
"a_id": [
"dqhzzhv"
],
"text": [
"This is generally because of the weather at night. At night the ground radiates heat in the form of infra red light. Clouds are largely reflective of infra red, so if it's cloudy the heat gets trapped and its warmer the following day. If it's not cloudy the heat is lost and the next day is colder."
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gboa6 | Why do humans have such revolting reactions to gore and death while animals don't seem to care and happily eat each others cadavers? | Biology | explainlikeimfive | {
"a_id": [
"dqhzogu",
"dqhypd4",
"dqhxwiz",
"dqhzlfk"
],
"text": [
"Because most humans are raised in a world where they do not require direct exposure to gore and death to survive. There are lots of cases where humans in specific situations have resorted to cannibalism when the choice is either that or die,and occasionally societies of \"headhunters\" make it a specific point. But for most of us living conditions no longer require us to do it as a standard that we're exposed to since the day we're born, so we don't.",
"Familiarity, or lack thereof, has a lot to do with it. There are people who work in abattoirs, butchering mammals to feed other mammals. Medical students have to dissect other people as part of their studies. They either get used to it or have to change job.",
"What animals are you thinking of that “happily” eat cadavers of their own species?",
"a lot of it is due to the evolutionary benefits of our feelings of disgust. We are usually disgusted by things that pose a threat to our health - corpses, rotting meat, shit, piss. As stereoroid says, we can train away that feeling of disgust, but it is hardwired into us"
],
"score": [
7,
6,
3,
3
],
"text_urls": [
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7gbs26 | Why is snoring louder when I’m drunk ? | Biology | explainlikeimfive | {
"a_id": [
"dqhzo0m"
],
"text": [
"Alcohol relaxes the muscles in your body, so if you fall asleep drunk, (sleeping already relaxes the muscles somewhat even when you're sober), the muscles in your neck and throat aren't suporting your airway as much, which means you have to breath longer or harder to get the same amount of air. More forceful breaths means more vibrations of the tissue in your throat and palate that cause louder snoring, or snoring if you don't normally do so."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gbwef | How do archaeologist find hidden cities and evidence? How did some get buried and lost in the first place? | Other | explainlikeimfive | {
"a_id": [
"dqhz6lb"
],
"text": [
"Probably no one in history ever said: let's abandon this city and bury it under sand so no one will ever find it again. What happens instead is a slow 'natural' process. It still happens today. Mayor causes are catastrophes (vulcano, earthquake, flooding, you name it), environmental destruction (pollution, deforestation etc.), climate change (flooding of coastal areas in various periods of human history, growth of a desert, exploitation of water resources by overpopulation etc.), economical or political reasons (migration, urbanisation, war). However, a village or city looses it's population, mostly not from one day to the other, but over decades. Then the nature slowly takes back the human built structures. It is overgrown by plants, and rotting plants become soil, slowly covering the decaying ruins. A rather recent example of this is basically what happened to the ukrainian city of Prypjat (Chernobyl). [here is an image]( URL_0 ) How to find evidence? Well there often is literature mentioning a city in a certain location (that is for example how the ancient city of Troy got re-discovered). Also nowadays you can use aerial photography that sometimes uncovers still visible structures when seen from far above. Other methods are scanning the ground from above using ground-penetrating radars to find underground structures. Also sometimes metal detectors can be useful, and random findings of nearby living citizens such as farmers who dig up the ground lead to the discovery of a city or ancient structure. Also cities are often built on older cities because the location is great (near a river or trade route), so in some european cities (and most likely elsewhere too) they find stuff literally every time someone wants to build a new house."
],
"score": [
9
],
"text_urls": [
[
"https://www.bund.net/fileadmin/user_upload_bund/bilder/atomkraft/Tschernobyl/tschernobyl_freizeitpark.jpg"
]
]
} | [
"url"
] | [
"url"
] |
|
7gbxzw | Why is asphalt black? Would Concrete or another material not work better? | Does the asphalt not make the surrounding area hotter? I have always wondered why we don't use concrete or change the color of asphalt or something else. | Chemistry | explainlikeimfive | {
"a_id": [
"dqhzj1k",
"dqhzaan",
"dqi6t3r"
],
"text": [
"The tradeoff between asphalt and concrete is complicated, and there are lots of reasons to choose one or the other: * Asphalt is a lot quicker to build. This particularly matters when resurfacing existing roads (as opposed to surfacing newly-built roads), because minimizing the amount of time the road is shut is very important to drivers. * Asphalt is a much cheaper material, which is obviously attractive. * Concrete has a much longer lifetime than asphalt. It generally will last 40-50 years before replacement, whereas you have to replace asphalt every 10 years or so, and it doesn't require regular patching. * Concrete deals with extreme heat and other adverse weather better. * Asphalt is easier to repair when minor problems occur. If a chunk of concrete breaks, you need to replace the entire section of road, whereas you can patch small pieces of asphalt. * Concrete gives drivers better gas mileage, because it doesn't warp as easily and so cars ride more smoothly on it. * Asphalt is safer in adverse weather, because rain and snow can partially seep into the surface, so they don't form a low-traction layer on top as easily. * Concrete is made from more environmentally friendly materials (mostly just limestone), whereas asphalt is mostly made from oil. * Asphalt is more easily recyclable into more asphalt, since you can melt it down, but it's hard to recycle concrete. Those considerations are much more important than whether or not the road surface gets a bit hotter due to asphalt being darker than concrete.",
"Asphalt and concrete are completely different substances. This goes well beyond the color. Concrete is cement + aggregate (rocks). Asphalt is petroleum tar + rocks. They have different costs, difficulty of working with & durability. Asphalt is much cheaper & easier to lay down.",
"Only new asphalt is really black, in a while the gravel inside gets exposed and dust settles on the black tar, so it's almost as grey as concrete. The heat absorption is not a very relevant factor. You can't lay concrete instead of asphalt on most roads because there is to solid foundation, so the concrete would crack as the land changes. You could lay it down in shorter blocks, essentially deciding to have cracks in it already, but it's annoying as hell to drive on and constantly hearing/feeling dunk, dunk, dunk, dunk..."
],
"score": [
30,
4,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7gd1ai | Why does both warming and icing some injuries have beneficial effects? | When I get ankle sprains or bruises for example, I stick them on ice to reduce swelling and speed up recovery. But if I have an aching back I'll try and heat it up a bit to soothe the pain. Is that just wrong? | Biology | explainlikeimfive | {
"a_id": [
"dqi4syd",
"dqi4uob",
"dqi7xdx"
],
"text": [
"Warming relaxes muscles, and brings blood into tissue (which speeds healing). Icing helps prevent/reduce inflammation.",
"It isn't futile, changing temperature does affect the body. Coldness makes blood vessels contact, reducing blood flow. That is why it's effective with swelling. Warming does the reverse, and increases blood flow. Not sure how it helps with pain though. Maybe it helps the area recover faster.",
"In cases where swelling is a concern (too much blood/fluid in an area) icing helps reduce the flow of blood/fluid to that spot and thus reduce the pain associated with swelling of the tissue. In cases were there isn't enough blood flow, or there is no swelling at all but still some pain/discomfort, warming helps to promote blood flow which can speed up the healing process by speeding up the process by which the tissues receive the nutrients they need to rebuild. Heat also helps muscles relax as the colder/cooler an area of your body is, the more tense those muscles are going to be."
],
"score": [
11,
5,
4
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7gd8ce | How do we disable or disregard most sensory inputs when we’re asleep? | Biology | explainlikeimfive | {
"a_id": [
"dqjd6pk"
],
"text": [
"Keeping it simple the brain cuts down on not needed processes. However it's on 'standby' this is why hearing your name called will wake you. The brain can hear your name and realise you are needed and wake you up.. Ever been in a loud place and someone called your name? Same idea. You cut out unnecessary information and sift out what's needed.."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gdc10 | Why dont any highways/private tolls have speed limits above 85MPH? Why has no road in America ever attempted no-speed limit zones? | Other | explainlikeimfive | {
"a_id": [
"dqi6pqp"
],
"text": [
"The interstates in Montana used to have daytime speed limits of \"reasonable and prudent\". It was eventually changed because the courts decided that was too ambiguous, it did not define what was legal and what was not."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7ge14s | What does overclocking do to my processor? | Technology | explainlikeimfive | {
"a_id": [
"dqicsm0",
"dqic493",
"dqicmfi"
],
"text": [
"You know how in the old times ships used to have a bunch of people with oars, and [a guy with a drum]( URL_0 ) to set the rhythm? Some people are weaker, some are stronger, so if you let everyone do what they want, you wouldn't go anywhere. If you want to go straight, the people on both sides of the boat have to row at the same rate, or the ship will start turning. So you have a guy with a drum setting a beat, so that everyone pushes at the same rate. There's also going to be some speed at which all the rowers can go forward comfortably. That's what the CPU clock does. Overclocking is just banging on the drum faster. CPUs are also like that. They have a bunch of components, some of which are faster and some of which are slower. The clock synchronizes everything. Usually there's a bit of margin, so if you run the clock faster, you get better performance. But if you overdo it, some parts of the CPU won't get their stuff done in time, and the synchronization will fall apart. Just like different ship crews are going to have different qualities, fabrication is imperfect. Some CPUs will have better made internals than others, and will have a higher maximum speed at which they can operate correctly.",
"You put a little more voltage into it, the CPU \"cycles\" through its operations at a slightly faster rate of 3.5Ghz instead of 3.2Ghz giving you a marginal increase in performance. But as you're putting more voltage into it, more heat is generated as a result.",
"Overclocking runs the processor chip at a rate faster than the rate the manufacturer guaranteed it would work at. The manufacturer tests chips and provides a few speed ratings as appropriate. However, every part if different. The manufacturer wants to minimize the number of parts returned for not meeting the specs, so it is very conservative in marking. If you want to get the most performance out of the chip, and you are okay with occasional failures, then you can overclock it."
],
"score": [
6,
3,
3
],
"text_urls": [
[
"https://www.youtube.com/watch?v=WXh1tW16V-8"
],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7ge1e2 | Why is hand sanitizer not effective against c-diff bacteria? | Biology | explainlikeimfive | {
"a_id": [
"dqicnww",
"dqjbre9"
],
"text": [
"Some types of bacteria, like *C. difficile*, are able to go into a state of suspended animation by [forming spores]( URL_0 ). These are different from fungus spores, but we call them that anyway. While in spore form, the bacteria aren't doing anything. They can't eat or reproduce. The upside is that they are pretty much unkillable, and can wake back up when they encounter the right conditions.",
"Use strongcide from URL_0 : its an clinical grade over the counter anti microbial that is the only FDA approved product that kills C-diff, MRSA, staph, impetigo, and ALL other superbugs on contact. Essentially it’s the hand sanitizers that kills the .01% that hand sanitizer doesn’t- which is actually all the harmful bacteria"
],
"score": [
12,
5
],
"text_urls": [
[
"https://micro.cornell.edu/research/epulopiscium/bacterial-endospores"
],
[
"www.strongholdtechnologies.com"
]
]
} | [
"url"
] | [
"url"
] |
|
7ge1tg | If I'm eating a lot of salty food one day, can I drink extra water that day to partly counteract it? | Biology | explainlikeimfive | {
"a_id": [
"dqiip6v",
"dqihbvm"
],
"text": [
"Wouldn't keeping the sodium/potassium balance in check be more important?",
"He obviously means how water dilutes your bloods content of salt and although his question is technically right, eating excessive amounts of salty food isn’t a great idea, drinking tonnes of water with it will just help mitigate the concentration of salt and the effect on his body"
],
"score": [
3,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7ge1zl | If I sell stock, who buys it? | Economics | explainlikeimfive | {
"a_id": [
"dqicnjc",
"dqical0"
],
"text": [
"The stock market matches buyers and sellers in real time. You own shares in XYZ Corp you want to sell. So you put in a sell order. At the same time, the exchange is taking buy orders from investors wanting to buy the stock. It matches the buys and sell orders. If there are more buyers than sellers, the price will go up. If there are more sellers than buyers it'll go down. Until there is a balance in shares demanded by buyers and sellers.",
"Whoever wants to buy it. If nobody wants to buy X stock, you can't sell it. There's just so many transactions going on constantly, unless you're trying to sell a large quantity of a stock (especially not a popular one), you'll never run into a situation where you don't have a buyer."
],
"score": [
5,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7gedwm | Why do some things only taste good after a few tries? | Biology | explainlikeimfive | {
"a_id": [
"dqiez41"
],
"text": [
"Your body automatically rejects new bitter flavors, as many poisons are bitter. But once you have tasted them several times and suffered zero ill effects, your nervous system (basically your brain) starts to adjust."
],
"score": [
9
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gem2p | How did the enigma machine work, and why was it so hard to crack the code? | Technology | explainlikeimfive | {
"a_id": [
"dqii130"
],
"text": [
"You know a letter replacement code that kids use? A very simple one is every letter is shifted 13 spaces, so if your message has an A it becomes an N, B becomes an O etc. Those are easy to break because some letters are used more frequently than others and your encoded message preserves the frequency of the letters. As an example, shifting each letter 13 places, \"This is my secret message\" becomes \"Guvf vf zl frperg zrffntr\". Someone might notice there are a lot of letters R, G and F in my code, and suspect those letters might be E, A, T, I, or O (the 5 most common letters in English), and pretty quickly be able to guess secret or message, then figure out the whole thing. To make codes harder to break, you can change your cipher for each letter, so if the first letter if shifted 13 spaces, the second might be shifted 2 and the third might be shifted 24 spaces. Using a system like that a message like AAA would now be NCW, that's a lot less obvious than an encoded NNN. This type of code is much harder to break by hand, even if the sequence is pretty simple. The enigma machines shifted each letter by different amounts, using lettered wheels that rotated and made different connections with each other (changing the shift for each letter pressed), and further changed things by using plugs that didn't just rotate letters, they substituted them in a non-rotated way (sort of like manually converting all your As into Qs and Bs into Es then applying the shift to each letter in the message). It was readable because an encoded message put into the same machine would be decoded, if the settings started at the same position (the tricky part then becomes getting the set up information transmitted to the users so they were using the right settings each day). It was hard to crack because with all the shifting and converting, there were 158,962,555,217,826,360,000 different starting set ups that could be encoded, and to crack the code you had to figure out how the machine worked, and then which setting was used for an encoded message."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gfc6w | Hemorrhagic stroke vs. brain aneurysm | What's the difference? The mechanism/causes? Treatment? Prognosis? | Biology | explainlikeimfive | {
"a_id": [
"dqitb3x",
"dqivq5p"
],
"text": [
"Hemorrhagic stroke is a vague term which can mean several very different things. An ischemic stroke (an obstructed artery which results in the death or damage to a part of the brain, due to lack of oxygen/blood flow) where the damaged brain tissue starts bleeding as the damage progresses. This is more precisely termed \"hemorrhagic transformation\". A collection of blood within the brain tissue, caused by damage to a small blood vessel. This causes a bubble of blood to collect within the brain tissue, putting pressure on the surrounding brain tissue, and causing it to be damaged (due to pressure from being squashed). This type of stroke is more precisely caused \"intracerebral hemorrhage\". Bleeding into the fluid space around the brain tissue. The brain (and spinal cord) are surrounded by a small space filled with clear watery fluid called cerebrospinal fluid. A membrane called the \"arachnoid membrane\" forms the outer boundary to this space. The arteries to the brain run in this space. If one bursts, then blood can mix with the fluid filling the space underneath the \"arachnoid\". This type of stroke is more precisely caused a \"subarachnoid hemorrhage\". Most strokes (about 85%) are ischemic strokes, meaning about 15% are hemorrhagic strokes. Technically, hemorrhagic transformation is not a hemorrhagic stroke, but the terms are confusing, and doctors sometimes get them confused. Intracerebral hemorrhage has a variety of causes. The commonest is high blood pressure, which can burst the small arteries in the brain tissue. However, there are other causes, drugs like cocaine, amphetamine, meth, etc. all spike the blood pressure and also cause inflammation of the small arteries weakening them. A less common cause is an abnormality of the blood vessels, where abnormal vessels grow to connect an artery and vein (called an arteriovenous malformation, with a slightly different variant called an arteriovenous fistula). A vessel disease called cerebral amyloid angiopathy is also a potential cause. Subarachnoid hemorrhage is caused by bursting of a blood vessel, not within the brain, but in the space around the brain. Subarachnoid hemorrhage is very rare, but is usually caused when an aneurysm of an artery around the brain bursts. An aneurysm is a section of artery which has blown up like a balloon, from the blood pressure, because of some sort of weakness in the wall. Aneurysms are not guaranteed to burst, and most probably never do. Less commonly, subarachnoid hemorrhage can be caused by bleeding from a vein, or due to an unknown cause, or because of a vascular abnormality like the arteriovenous fistula described above, or cerebral amyloid angiopathy. The treatment of intracerebral hemorrhage is surgery to remove the blood clot if it is causing serious brain compression. If the brain compression is not life threatening, then the treatment is diagnose and treat the cause, then rehab to retrain function. For subarachnoid hemorrhage, diagnosis of the cause is important. If it is due to a burst aneurysm, then this is very serious, because if an aneurysm has already burst, it is likely very weak, and there is probably just a small blood clot holding it together. The treatment of aneurysms depends on blocking up the aneurysm in some way so that it doesn't fill with blood, or any blood that is left forms a solid clot. Previously, this used to be done by surgery to put a spring loaded clip (like a paper clip) over the aneurysm, in line with the normal artery, so that the aneurysm is sealed off from the artery, by pressure from the clip. The blood in the aneurysm clots solid, and eventually, turns into a lump of scar tissue. These days, aneurysms are usually treated from inside the artery. The usual technique is to insert some type of implant into the aneurysm via a very fine tube inserted into the artery (usually threaded up from a large artery in the groin). These implants have are usually small springy coils of platinum wire. They are pushed out into the aneurysm, and using memory metal technology, they reform into tangled coils. These then lodge in the aneurysm, and the network of tangled metal wires blocks the blood flow. Any remaining blood in the tiny spaces between the wires, will then stagnate and clot.",
"Aneurysm refers to the structure of the blood vessel. Aneurysm means all three layers of a blood vessel are weak so the blood vessel pouches out like a balloon instead of being like a straight pipe. This usually happens due to genetics but bad diet, smoking and high blood pressure can also cause this by damaging the walls of your arteries/blood vessels. A haemmorhagic stroke is a diagnosis. Stroke means infarction (lack of blood) to the brain. Haemmorhagic classification means the cause is a broken blood vessel causing bleeding. This is opposed to an ischaemic stroke where a blood vessel gets blocked so blood doesnt flow to a part of the brain. This is an important distinction as it determines treatment. Ischaemic strokes you want to burst the clot either via medications or by clot retrieval. In haemmorhagic strokes you need neurosurgery to drain the blood. Depending on where the haemmorhage occurs you get different labels ie intercerebral, subarachnoid, subdural, extradural etc. The mechanism of a haemorhagic stroke includes high blood pressure, trauma, a vessel malformation or an aneurysm. If an aneurysm is identified in imaging you can clip and coil it with neurosurgeons to minimise the chances of that aneurysm bursting and turning into a haemorhage. TLDR; aneurysm = vessel is damaged + misshapen, haemmorhage = vessel has burst. An aneurysm can haemorhage and turn into a stroke but you can coil/clip it before that happens if you find it. Sorry for spelling errors, typing on phone whilst pooping"
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
7gfg7z | Why does chewing more prevent weight gain? | Biology | explainlikeimfive | {
"a_id": [
"dqindt9"
],
"text": [
"Food takes time to reach the stomach, and you'll notice if you eat and then wait you'll be less hungry. Chewing more simply takes more time to do, and so you get full with less food"
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gfitv | How do those sexual harassment accusations work? | Can I just go to the press and say that 5 years ago I was harrased by my boss who might be a public person? Asking for a friend. In other words how do they know that I am not lying? | Other | explainlikeimfive | {
"a_id": [
"dqiokfs",
"dqj3w2s"
],
"text": [
"They do their research and ask you for your evidence. They get sued pretty hard for defamation (and so do you) if you publicly say something aggressively negative about someone else. Anyone who is in a position to sue for wrongful defamation is. I understand why a lot of people doubt the allegations, but anyone who has had a negative career impact and is innocent should have taken legal action, and only some of them have.",
"They don't. Everybody may be accused of something they allegedly did 20 years ago and they have no way of defending themselves. None of those allegations will end up in convictions. Libel laws are set up so that THEY need to have a proof that you are the liar. If you were with a person in a room with no witnesses there is no way for them to prove that YOU are the liar. There is no way to prove that you are telling the truth, either, so it's a wash in the court. However, public opinion doesn't care about evidence and the feminist-dominated media takes all allegations as true, no matter how flimsy. By the way, the standard of \"sexual assault\" is set so low that every man and every woman qualifies. Asking a woman out on a date is considered harassment, nowadays, depending on the mood of the girl and the attractiveness of the man."
],
"score": [
14,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
7gfiwq | Why do slow drivers still drive in the left lane ? | Other | explainlikeimfive | {
"a_id": [
"dqio18l"
],
"text": [
"More often than not, it's likely due to one of two things - lack of awareness (they just don't know they're slowing down traffic/care that anyone else is out there), or laziness (they're not exiting anytime soon, so get all the way over). Neither is particularly safe behavior, which suggests they're likely bad drivers. Maybe some are trying to police everyone else - \"I'm going the speed limit, that's fast enough!\" Why people do anything is a mystery, though, really, unless you ask them, right?"
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gfjqa | Why is it hard to swallow when you’re on the verge of tears/crying? | Every time I start crying, I get a lump in my throat which makes it hard to swallow. What is that? | Biology | explainlikeimfive | {
"a_id": [
"dqj4ef8"
],
"text": [
"When you are crying, your body translates that as stress. As any stressful situation, the body will try to prepare itself by pumping more sugar and oxygen into the muscles. To pump more oxygen, the lungs need more air to be filtered, and so it be, breathing more rapidly. The body also expands the reflex muscle in the throat that opens your airway called \"glottis\" as much as it can. When you try to swallow, the glottis needs to close the airway, and your swallowing muscles \"fight\" the swollen glottis, resulting in the unpleasant feel you are so familiar with. That \"lump\" in your throat."
],
"score": [
28
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7gfpy3 | Why does sexual cannibalism exist? How is it beneficial for a specie? | Biology | explainlikeimfive | {
"a_id": [
"dqivurn",
"dqipyex"
],
"text": [
"Nobody else has mentioned: it's a free meal for the mother. You've got goodness knows how many eggs to lay, the extra nutrients won't hurt.",
"It only works biologically if you have a huge number of eggs/children per single sexual encounter. That way you keep the territorial male away from your children and prevent any other females from getting the genes you determined to be important. Its more for biological competition within a species"
],
"score": [
5,
5
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7gfydq | Why are there such virus inducing ads on nearly every site? And who lets them stay there? | Other | explainlikeimfive | {
"a_id": [
"dqit57j",
"dqirkfp"
],
"text": [
"Sites that are less popular but that want to get more money will frequently accept advertising deals from shadier ad networks that offer higher rates. Those ad networks offer higher rates because the ads they serve are disreputable, and most sites don't want to work with them so they have to raise their payout rates to get placements. You'll rarely get those kind of nasty ads on the very popular sites (NYT, google, reddit) but you'll get them on more marginal sites with hosts that are trying to monetize more than their traffic allows.",
"why do you? I recommend using an adblocker such as Adblock or Ublock. They exist because on most sites only the space is sold on where the add is displayed, and this place then is shared by companies displaying adds. These companies again get money from companies or basically everyone to display their add. Its so many adds some of these companies don't even know which ones they are displaying in the end."
],
"score": [
8,
7
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7gg62j | how do batteries (phone, laptop) get charged? And why does it take an lengthy amount of time? | Technology | explainlikeimfive | {
"a_id": [
"dqix7uu"
],
"text": [
"Batteries employ reduction/oxidation reactions, also known as electrochemical reactions. Two compounds are contained in the battery, one is an oxidiser and the other a reductor. When you use the battery, the reductor lets go of some of its electrons, which flow out of the negative terminal of the battery, through your equipment (providing electrical energy to it), and back into the battery, via the positive terminal to the oxidiser, which takes up the electrons. These chemical reactions are reversible. A charger pushes the electrons the other way around, reversing the chemical transformation of the oxidiser and the reductor that occur when they exchange electrons. One important reason that you cannot charge the battery very quickly is that the process of charging/discharging generates heat. This must be dissipated, which takes times. Also, sometimes compounds must migrate towards electrodes in the battery. This also takes time."
],
"score": [
5
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7ggb97 | Why are objects in the rearview mirror closer than they appear? | Physics | explainlikeimfive | {
"a_id": [
"dqiue7h"
],
"text": [
"In order for it to be effective, the passenger side mirror is parabolic. This means the surface of the mirror is curved, allowing for a wider range of visibility. However, curving the mirror also effects the accuracy of its magnification, which is why things in the passenger side mirror appear to be further than they actually are."
],
"score": [
15
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7ggc25 | Why do the list prices/MSRPs of online retail items [e.g. Amazon] change while the sale prices stays the same? | Economics | explainlikeimfive | {
"a_id": [
"dqiuocb"
],
"text": [
"It really depends on the item. If, for instance, the item in question is the Dildtronic Vibromaster 5000 and it has an MSRP of $100, but Amazon has some for $60, but then Dildtronic puts out the Vibromaster 6900 with new Turbo-buzz action, and *that* one is selling for $100, then the MSRP of the Vibromaster 5000 might fall to keep up sales of both models."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7ggdxs | How does chapstick work? | Chemistry | explainlikeimfive | {
"a_id": [
"dqj0gfz",
"dqjklo1",
"dqjiyfq"
],
"text": [
"Chapped lips are due to them losing moisture. Chapstick simply leaves a protective layer over them so that moisture does not evaporate from them as quickly",
"Most lip balms (Chapstick is actually a specific brand name) have two or three functions. The first and main function is to create a hydrophobic (waterproof) barrier on your lips to prevent evaporative loss of water from the exposed cells. Usually petrolatum or beeswax is used. That water loss kills cells while changing their shape and size which creates the hardening, cracking, bleeding, and pain of chapped lips. All lip balms will provide some UV light protection and many modern brands can provide very significant protection (SPF 50+). This simply helps keep those exposed cells healthy and stops what could be a secondary danger to those cells. Some lip balms which are usually labeled as \"medicated\" contain mild analgesics. These can be effective in reducing the pain of chapped lips but some physicians and researchers are concerned that preventing the pain may cause people to not notice when damage is increasing. Also, the analgesic effect will run out well before your lips heal leading to a simple \"dependence\" on constant reapplication to avoid pain. It may be wise to avoid these balms unless your chapped lips have reached the point where pain is affecting your life. Bonus trivia: lip balms are not compatible with latex condoms. Take care when the two may come in contact.",
"Water is a polar molecule. Lipids (fats) in chapsticks are non-polar. Polar and non-polar don’t mix so applying a non-polar layer on top of the cells in your lips prevents water from leaving your cells. This keeps your lips from drying out and becomming chapped. Source: Biology freshman year of highschool Edit: Change “Lipids (fats)” to “Petrolatum”"
],
"score": [
1391,
192,
29
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7ggicc | How can a coat check say they are not responsible for damage or loss to my coat? | Other | explainlikeimfive | {
"a_id": [
"dqiwen2"
],
"text": [
"Because it doesn't really mean anything legally. Statements like this, signs in parking lots, and written liability waivers are largely for show. Were you to ignore the waiver, and sue for the cost of your lost jacket, the judge would not stop you because of their claim. They could still absolutely be liable for replacing the lost jacket. So why even bother having waivers in the first place? Because it makes customers think that they have no legal recourse, so they don't push the issue after an item is stollen or someone gets hurt. It also shows the potential judge that the customer was warned of the potential danger before participating, which can be a helpful defense in some personal injury cases."
],
"score": [
12
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7ggpjy | If water is transparent, how does it still cast a shadow? | Physics | explainlikeimfive | {
"a_id": [
"dqixr61",
"dqixspe"
],
"text": [
"It's not completely transparent. It has a slight blue color, reflects some light, refracts some light.",
"its not fully transparent and some light gets reflected at it's surface. it's dark in deep waters."
],
"score": [
8,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7ggpr0 | BCAA's, Fish Oil, Creatine, Protein and other workout supplements, what is their purpose? | I would just like to get more knowledge of the science behind each one and the function. | Biology | explainlikeimfive | {
"a_id": [
"dqiykyq"
],
"text": [
"Creatine is part of your body's energy system. Your body will use stored ATP within the first second and then creatine for the next 3-4 seconds. If you're a bodybuilder, taking creatine may increase your anaerobic capacity (both are anaerobic sources). There's science that indicates supplementing increases your pool slightly, but you excrete the rest so it has high diminishing returns. Bodybuilding requires anaerobic activity, because aerobic takes much longer to get up and running. It has more significant effects for sprinters, bodybuilders, powerlifters, etc but not that big a deal for marathon runners, cyclists, etc. It can cause you to gain weight from retaining water though. Fish oil or omega 3 is used in the biosynthesis pathway for anti-inflammatory molecules. It can balance out omega-6 in your diet which usually creates inflammatory molecules. Inflammation is a necessary requirement for your body to heal, but excessive amounts just causes unnecessary pain. It can reduce excessive swelling and pain, and can help reduce the time to recovery. Muscle is made of protein. You need to eat protein for your body to build muscle and give other cells protein. You use it for essential amino acids that you can't make yourself to build proteins in your body. BCAAs (Branched Chain Amino Acids) are very new. People say it stimulates muscle growth, but research suggests the opposite. It actually slows down both growth and loss. Instead, its used when people stop eating as much protein to slow down muscle loss and it also has some effects to improve healing. I couldn't tell you about \"other\" because it really depends. A lot of stuff is junk though, but omega-3 PUFAs, creatine and protein are basically essential building blocks your body needs and giving more helps when you're getting big. BCAAs have mixed evidence though, and are not necessarily effective."
],
"score": [
11
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
7ggrwi | Can organs that had been donated be reused/passed on? | Biology | explainlikeimfive | {
"a_id": [
"dqiztns"
],
"text": [
"Yes. There are a few cases of organs going through multiple transplants. This is rare because death can damage an organ. It means an organ must survive the first death, transplant, and the death of the second patient and make it to the third. This usually happens when the 2nd patient suffers severe cranial trauma or stroke, but is otherwise healthy. The transplant process itself scars the organ around the cuts, so that scar tissue must be removed during each transplant, so indefinite transplanting cannot occur."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gh1ju | If blood circulates around the body in a circuit how does cutting off a limb not break the circuit and stop the flow? | Biology | explainlikeimfive | {
"a_id": [
"dqj0kfi",
"dqj1sa1"
],
"text": [
"Because blood doesn't circulate in a circuit. It branches out and the converges back together.",
"Blood doesn't go around the body, like a lazy river, it doesn't make one big loop stopping at a lot of places. Instead you have like a bunch of 2 lane highways going to every part of your body. Blood goes out from the heart to that spot, then take a similar route back via the veins. The blood that goes to your right big toe and back never went anywhere near your left foot or arms or head on that trip. URL_0"
],
"score": [
17,
10
],
"text_urls": [
[],
[
"http://78.media.tumblr.com/tumblr_luzphsb9JM1qf8cm7o1_r1_1280"
]
]
} | [
"url"
] | [
"url"
] |
|
7ghizn | How do motion detectors detect motion in the dark? | Technology | explainlikeimfive | {
"a_id": [
"dqj5be1",
"dqjgmo7"
],
"text": [
"You have two common types of motion sensors - passive infrared(PIR) and Ultrasonic. The most common type is PIR which sees IR which is emitted by hot objects. There is a special lens in front of the sensor so a warm object moving through its field of view creates sudden transitions that are easy to detect. Since it is relying on heat emissions it works fine with or without light. Ultrasonics send out a sonar burst and effectively echo locate like a bat. They check the sound they get back after each one and compare it to the last one, if it changed significantly then something in the space moved and they trigger",
"While I can't speak to the newer tech I've seen discussed here, older motion detectors *do not* work in the dark. I've fooled them many times. Older detectors use a [cadmium sulfide cell]( URL_0 ) in front of a fresnel lens. The sensor is a resistor that passes electricity depending on the amount of light hitting it. Passing that light through a [fresnel]( URL_1 ) lens scatters it. Now you have a sensor that trips according to light variations it \"sees\" over time and because of the scattering the sensor \"sees\" a nice, wide, blurry area. Stand still, let all the light and shadows remain static, and nothing happens. Move through the lenses ( < -sp?) eye and the resistance on the circuit changes, tripping the alarm. Move *really* slow and the sensor doesn't trip because the incoming light doesn't change fast enough. Not sure how the timing works but you don't want your alarm to trip because the sun moved a shadow a bit."
],
"score": [
36,
3
],
"text_urls": [
[],
[
"https://cdn.shopify.com/s/files/1/1490/5112/products/02761657_01_cc57aee7-c3ff-4fc2-8201-fb46bcf45d42_grande.jpg?v=1478049888",
"http://partsolutions.com/wp-content/uploads/2014/09/fresnel-lens-1.jpg"
]
]
} | [
"url"
] | [
"url"
] |
|
7ghka4 | How does red dot sights work? | you know, the red point to aim in games with guns. and in real life too. if normally with a gun you need two separate points to know the gun is aiming the correct way (one bump near the trigger and another at the end of the cannon) how does only one red point in a glass works for aiming?? | Technology | explainlikeimfive | {
"a_id": [
"dqj523j",
"dqjc6r4",
"dqjl88v"
],
"text": [
"The dot in a red or green dot sight is not actually a coloured point that's hovering in a fix spot in the air like an iron sight does. Instead, the red dot you see is a reflection of a little red lamp that falls onto a spherical mirror which filters out only the red (or green) spectrum. This mirror is installed in a way that no matter what angle *you* look on it, the Red dot will always point towards the spot the bullet will hit. EDIT: That way the Red dot itself is virtual and basically only exists in your eyes, two people looking through the same sight at the same time from different angles would see the spots in different 3-dimensional places, but still pointed towards the target.",
"a red dot sight (also known as a reflex sight or a reflector sight) bounces a laser off of a reflector that is curved so that the angle the dot reflects off of it changes where it appears to reflect off of the reflector. The reflector itself is actually transparent, and that's what you are looking through when you look through the sight. The curve of the reflector is tuned so that the image of the laser that is reflected appears to stay in one position relative to the target that you might be looking at through the sight, with it ideally being kept in the center of the reflector. you could think of it as sort of the opposite effect of using a curved mirror to focus light to a point, where the image of the reticule is at the point, and your eye being able to see it from anywhere within a certain cone of vision. if you;re curious about the specific internal workings, there are some good diagrams on the [Wikipedia article]( URL_0 )",
"The other posters are correct in how the device functions. However, I think you are asking, \"Why is it an effective way to aim something even if it only has one point?\" The simple answer is it is built to have the dot lie on a parallel line to the gun barrel. It is worth noting that reflex sights are not for long range or precision shooting. They are more for close-medium range combat situation, i.e. getting all shots in a bad guy shaped target. To get the best accuracy out of a reflex sight, you should mount it as close to the barrel as possible so that the point of aim and point of impact are as close together as possible. This principal also applies to scopes as a perfect scope(mounted perfectly on a perfect gun) at 0 windage and yardage should only be off by the same distance it is away from the center line of the barrel."
],
"score": [
34,
7,
3
],
"text_urls": [
[],
[
"https://en.wikipedia.org/wiki/Reflector_sight"
],
[]
]
} | [
"url"
] | [
"url"
] |
7gi8m3 | Why aren't corporations reluctant to hire men with the wage gap? Wouldn't it be cheaper to fire the men and replace them with women? | Economics | explainlikeimfive | {
"a_id": [
"dqj9wbz",
"dqja4g1",
"dqjb8b0"
],
"text": [
"No. Because the wage gap doesn't actually exist. It's based off of a average of many different jobs. Most of the jobs that women have are just paid less than men's jobs. It isn't that they are getting paid less in the actually job",
"That's not how the wage gap works (at least in most cases). Two workers, one man and one woman, performing the same job function are typically paid the about the same. The average earnings of women tends to be lower due corporate environments that promote men more often than women or hire men more often for higher-paying positions than women.",
"As others have said, it's not that they can literally pay a woman less than a man. The wage gap is a statistic comparing the average earning of men vs. women, and represents a trend for men to be employed in higher paying jobs. For instance, you might have a man and woman who are similarly educated where the man is in an upper management position, and the woman is in a middle management position thanks to company culture or promotion biases etc.. You might have a man who chose to major in engineering, and a woman who decided to major in cosmetology, so the man works at Boeing, and the woman works as a makeup artist. Or you might have a man who works 9 to 5, 5 days a week, every week, all year, and a woman who has to take maternity leave because she chose to have children and needs to take time to raise them (while the husband often cannot take unpaid time off and expect to have his job waiting for him when he returns). TL;DR: women are paid the same as men in the same job, they just tend to end up in jobs that pay less, and spend fewer hours working in those jobs per year than men on average."
],
"score": [
79,
20,
5
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7gifhv | why can't horses vomit? | Biology | explainlikeimfive | {
"a_id": [
"dqjbs3o"
],
"text": [
"I am fairly certain giraffes can’t vomit because of the sheer amount of force/muscle/effort required to push their stomach contents that distance against the force of gravity. I would have to assume (if your information is accurate) that the same reasoning applies to horses (Never knew horses can’t vomit)"
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gifqa | How did drinking beer help out during the time of the bubonic plague pandemics? | I heard something about the plague not being transmitted through the beer for some reason. | Biology | explainlikeimfive | {
"a_id": [
"dqjcrie",
"dqjgzw3",
"dqjbk6g",
"dqjgvwz"
],
"text": [
"Bubonic plague is carried by fleas and rats (which have the fleas), so clean water isn't so much the issue for that particular disease. However, diseases that *do* spread through contaminated water, like cholera, aren't transmitted through beer because brewing beer involves boiling everything. This kills bacteria in it. Additionally, the alcohol in it will also kill the infectious bacteria. Alcohol sterilizes things.",
"Not necessarily beer, but a variety of alcohol and vinegar based liquids. The plague was spread by flea infested rodents but at the time, this wasn't understood. What was understood though, was that wine and beer tended to withstand taint by disease. They didn't rot or turn sour easily, and objects treated with them tended not to cause infections. A kind of hazy understanding of antibiotics but without understanding why it worked or what it attacked. There was [a . that became infected with the plague long after it had been wiped out in Europe. I think it was someone going into storage and opening a rug which had live plague fleas still in it. In any case the plague hit the town but the people were responsible and knew that it could start the plague all over again so they did something altruistic, and cut themselves off from the rest of the world until the plague had run it's course. In order to feed themselves, they communicated to other towns and people in the area and got them to purchase supplies which would be left just outside of town. In order to pay for them, they would leave coins, but they had to be certain that the coins wouldn't infect anybody, and so they chose a rock at the edge of town that had holes in it, and they filled the holes with vinegar, and placed the coins inside of them. The plague was contained.",
"The fermentation process involves sterilization. So beer is sterilized, making it safer to drink than unprocessed water.",
"I was plague doctor for Halloween so i have some notes. Originally diseases were believed to spread by gas or odor called miasma by the poor and the wicked. Thats why during bubonic plague plague doctors wore bird masks and filled the beeks with flowers and spices to fulter the bad smell so they wouldnt become sick. In england i belive there was a nobleman named John snow who determened that the common thing about plague hotspots was lack of clean water. I think he also noticed that people who drank beer in taverns rather than water were getting sick more rarely than others. I cant recall but i quess someone can fill the rest."
],
"score": [
98,
37,
8,
5
],
"text_urls": [
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7gih9w | why canned food last much longer than other packed food? | Why does storing food by canning it make it last so much longer than any other method? | Biology | explainlikeimfive | {
"a_id": [
"dqjhbkf",
"dqjgb24",
"dqjm8u8",
"dqjhcor",
"dqjgswz",
"dqjf4bq",
"dqjlqtv",
"dqjdwkl",
"dqjqzkj",
"dqjwb6i",
"dqjryl0",
"dqjk3lv",
"dqkk6zd",
"dqk2v3y"
],
"text": [
"Food spoilage is mostly caused by bacteria and fungi in the environment. There are a lot of them naturally present, and generally don't harm the plant or animal that they're living on. But when that organism dies, it literally becomes the Hunger Games. The microbes start ripping apart the nutrients present in the dead organism, and creating environments that kill as many of their competitors as possible. Some of that competition is good for humans: pickles, vinegar, cheese, bread, and plenty of other foods are basically just us picking the winner in those Hunger Games. We give the microbes we like (L. Plantarum, etc) a nudge that helps them kill their competitors that we don't like (C. Botulinum, etc). But, what does that have to do with canning? Canning is the \"kill everything\" strategy. The food is completely sterilized and all microbes are killed. Good guys, bad guys, it doesn't matter. Kill everything with fire (literally with fire, if you're using gas heat). With everything dead, there's no Hunger Games, and the food doesn't get digested by them -- it stays fresh forever. ... if it's sterile. If the strategy is to kill everything, you have to make sure that not one single microbe survives. That's hard to do. C. Botulinum in particular is a tough little bastard, can kill you, and you've killed all the L. Mesenteroides and other \"good guys\" who might have fought against it. For that reason most commercial canned foods include some additional preservatives -- the \"chemicals\" -- that people complain about. But those chemicals are important for the reasons I described. Canning tries to kill every last living thing in the food product, and if there's a single survivor you'll die eating it -- a little chemical help makes sure that there are no survivors. (Edit: Corrected some typos that people have pointed out. Thanks for all the positive comments! And, I'll stand by my use of \"literally\" here, so don't bother complaining more about it.)",
"So there is bacteria everywhere right? This bacteria causes food to spoil. Once you put food in a can and create a hermetic seal (fancy term for saying nothing gets in or out, not even air), you have to cook the can. It is cooked in a giant pressure cooker with steam until all of the dangerous bacteria is killed off. The food will last as long as the seal. For a canned good, the seam is made of 5 layers of metal. When stored at room temperature, if the coating on the can is good, canned goods should last indefinitely, however there will be a small drop in quality after 2 to 3 years. Highly acidic products can eat through the can coating after a while, and have shorter shelf life as a result.",
"There's 3 main ways of preserving food, all of which can be very effective. The first, canning, focuses on killing all the bacteria in a product, then sealing it so no new bacteria can get in. Irradiation is another form of the same concept. The second is altering the environment such that the bacteria there can't grow. That can be by removing water, adding sugar or salt in large amounts, or otherwise making it inhospitable. The final way is fermentation. The goal here is to stack the deck such that desirable organisms can outcompete the bad guys and prevent them from taking hold. Also, things like lactic acid (pickles) and alcohol (beer and wine) can help create an environment where other stuff can't grow. The very best ways of preserving things would likely be a combination of all three. For example, beer is boiled (type 1) with hops, which has some antimicrobial properties (type 2) fermented (type 3) then carefully sealed (type 1). A beer recovered from a shipwreck proved drinkable after 200 years.",
"Though canning (whether in cans or jars) can preserve some foods for a long while because canning typically sterilizes food, dehydration or other methods can be even more effective (consider the case of canned spaghetti). As an aside, \"best by\" and \"use by\" dates often have nothing to do with how quickly the food will go bad. Instead, they're often defined by how long the *packaging* can be expected to remain intact. This is why bottled water has an expiration date, for example, and why you can eat long-expired food so long as the packaging is still sealed.",
"The food is sealed in air tight then they blast the cans with heat that usually kills bacteria.",
"It won't, not necessarily. Vacuum sealing dried goods will preserve them for an incredibly long period of time, even longer if you put oxygen-absorbing and silica-gel packets in the sealed bag. Part of the deal with canning is that you start by sterilizing the contents with heat and steam. Killing most of the bacteria, and then putting it in an airless chamber, significantly impedes the growth of the remaining bacteria. You could theoretically sterilize a steak with radiation, and then vacuum seal it in heavy mylar bags, and have it be preserved in much the same way as it would if you'd canned it.",
"Food spoils because bacteria eat it. Canning stops that in three ways. First, it uses heat to kill everything off during the canning process. Second, it usually stores the food in a brine solution that destroys any tiny amounts of bacteria that might have survived somehow. Third, it makes it impossible for other bacteria to get in. Freezing also does these things, but it destroys the cell structure in the food too. Salting and smoking also does these things, but alters the taste and texture. Drying works very well and can in theory last decades, but requires careful storage. Honey never goes bad, all on its own. Early European explorers in Egypt ate 3,000 year old honey from the tombs of ancient pharaohs.",
"The food it heated so that the bacteria that cause food to rot are killed and then it is sealed so that oxygen can not spoil the food or allow more bacteria to grow.",
"Canning really isn't that great of a method, if your goal is to keep food for as long as possible, freeze drying or dehydrating food is absolutely the method to go with. There are dehydrated meals prepared for the war in Vietnam that you can add water to, cook, and eat today without any issues. The canned portion of these meals is usually compromised. Type of food helps as well, a guy on youtube has eaten a cracker from the American Civil War.",
"The canning industry is one of the most heavily researched and technologically advanced I have ever seen. There are thousands of different linings and processes fine tuned for each individual product they contain. Check out the details online, its really quite fascinating",
"Does anyone know if heating the metal causes chemicals go trickle into the food (and cause any side effects)?",
"The canning process involves sealing food in a non-permeable container, then heating it to a temperature hot enough to kill any microbes inside. This essentially creates a sterile environment inside the container that should be maintained until the seal is broken.",
"because you are cooking food long enough to kill every possible living thing in there with addition of removing air in the process.",
"A bit more ELI5 because I don't think y'all realize that a 5YO would need this part explained: We don't cook food and then seal it in cans. We put uncooked food into cans, then seal the can, then cook the food inside the sealed can. So for instance, canned tuna was actually raw when they put it in the can. [ Then all of y'alls other explanations about bacteria and fungus and sterilization, which are completely correct. ]"
],
"score": [
2218,
353,
60,
57,
17,
13,
13,
6,
6,
5,
4,
4,
3,
3
],
"text_urls": [
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7giovz | If tobacco, nicotine, no cigarette smoke are so harmful to the human body, why does the FDA allow them to be sold? | Biology | explainlikeimfive | {
"a_id": [
"dqjdhyx",
"dqjdeg3",
"dqjds9k",
"dqjdm3v"
],
"text": [
"Exhibit A - [The 18th Amendment of the US Constitution which established prohibition]( URL_0 ) Exhibit B - [The 21st Amendment of the US Constitution which was ratified just 13 years later and repealed the *wildly* unsuccessful and unpopular 18th Amendment and ended prohibition]( URL_1 ) Prohibition doesn't work. Banning cigarettes would have almost no impact on them, it would just lead to a large and abrupt black market and likely *increase* their usage as they reclaim their *cool* status. If you ban something people already have and like you just create a black market for it. It is far better to regulate it heavily and tax the crap out of it, at least then you still have a say in the production and distribution",
"1. The people would riot. Any political party that just out banned cigarettes would vote them out and vote in new people to undo the ban. 2. The taxes on cigarettes generates non-trivial revenue for the government.",
"The government is not in place to be a nanny for American adults. They already place heavy restrictions regarding age, where it can be sold, the big Surgeon General's warning on it, special taxes, etc. People want cigarettes. If you make them impossible to purchase legally, people buy them *illegally* from dealers. It would make organized criminals billions richer and much more powerful, just like what happened with alcohol prohibition.",
"Money -- it literally all has to do with money. Tobacco has been protected for a while - it is heavily ingrained in American history and there is a lot of legislative history that suggests the gov't of the US would never allow ciggys[tobacco] to be prohibited."
],
"score": [
48,
31,
9,
7
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/Eighteenth_Amendment_to_the_United_States_Constitution",
"https://en.wikipedia.org/wiki/Twenty-first_Amendment_to_the_United_States_Constitution"
],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7girxx | Why does using a cheap charger sometimes cause ghost-touches on my phone? | Technology | explainlikeimfive | {
"a_id": [
"dqjf2a0"
],
"text": [
"Generally what the cheaper chargers are cheaper because they have been made to a lower price point - often by removing parts that are not required for it to work, but required to reduce electrical noise on the output - and radiated from the charger itself. These parts are often the input filter, some parts of the output filter, and shielding that is there to prevent the power supply radiating electrical noise and interfering with other products. This noise which is normally attenuated to prevent it posing a problem can be picked up by the more sensitive parts of a phone, or a laptop, specifically touchscreens and touch pads, that work by detecting very tiny changes in capacitance, using very small signals. If you have noticed that some laptop chargers have a heavy 'lump' in the middle of the cable? That is a ferrite ring, also called a 'choke' used to made it harder for current to change rapidly in the cable, therefore suppressing high frequency 'noise' generated by the power supply."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gislg | Why does a car's windshield fog up in cold weather? | Chemistry | explainlikeimfive | {
"a_id": [
"dqje6lr",
"dqkq6xh"
],
"text": [
"As the water vapor in the air cools it condenses on the glass into tiny droplets. It is the same reason a cold glass will \"sweat\" and why rain happens.",
"It's caused by condensation. Condensation is the opposite of evaporation. It's a gas reverting to a liquid state. H2O carries a bit of a magnetic charge, and is almost always in our air. It will always be in a car when we're in it, as it's actually something we exhale. When it touches a cool surface, I.E. a cold windshield, the molecules slow down and get closer together (the condense of condensation), and will turn back into a liquid. Water vapor is stored much more condensed when it's hot out. But requires a cool or cold surface to bond to. And when the inside of a car windshield fogs up, it's due to the water vapor we produce bonding to the cold windshield. This is why cracking your windshield, or having a defroster that warms up your window will dissipate the fog. Hope this explains everything."
],
"score": [
11,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7giwtj | the difference in time signatures, including the more complex (to me) ones used in jazz, like 6/8, 7/4, etc. | i have yet to find an explanation that can change the only example i’ve ever known which is 4/4. is it just how many notes can fit into a bar? why can’t the bars just be made longer? don’t all notes and bars have to eventually come back to an even number, like in 4/4? 12 is all i can thing about... | Other | explainlikeimfive | {
"a_id": [
"dqjffw0",
"dqjjju2",
"dqjg266",
"dqjkb9u",
"dqjgb4m",
"dqjif1r",
"dqjflyq",
"dqjmdl1"
],
"text": [
"The bottom number indicates which type of note is a *beat*. Quarter notes (4), eighth notes (8), etc. The top number indicates how many beats per measure. So 6/8 says that eighth notes are a beat and there will be 6 beats per measure. 7/4 says that quarter notes are a beat and there will be 7 beats per measure.",
"The top number gives the number of beats in a measure, the bottom one designates the kind of note that gets one beat. So 4/4 is 4 beats to the measure, and a quarter note gets one beat. The time signature does not tell you where the emphasis is in the measure, though there are usual standards. 4/4 can have a primary accent (an emphasized beat) on the first beat, and optionally a secondary accent on the third beat. So it could be counted ONE-two-three-four or ONE-two-*three*-four. The measures repeat -- so for the portion of the music that has that time signature, all the measures follow that pattern. Some music keeps the same time signature for the entire piece, some change often. The overall rhythm of the song is mostly determined by its time signature. So, a different time signature can have a different speed -- time signatures based on 8th notes are usually faster, for instance. And time signatures can have a different number of beats in the measure, which changes the overall beat of the song. I'll give some examples. The most famous jazz piece of the 60s was \"Take Five\" by Dave Brubeck; it actually became a popular hit, i.e., known to the general radio-listening public, not just to people who knew jazz. It has 5 beats to the measure, quarter note gets one beat. The measure is organized as ONE-two-*three*-four-five. I recommend you look up Brubeck's quartet studio recording of Take Five, and just sit and listen to it at first. Once you're comfortable with that, I recommend another piece of his called \"Unsquare Dance\", in 7/4. The seven beats are organized as ONE-two-*three*-four-*five*-six-seven. Trying to tap your foot to this one can end up tying your ankle in a knot. It's mostly a drum solo, but pay attention to the last chorus; at the very end is a guffaw of surprise from the drummer at getting through that last chorus (if you're listening to his studio recording, that is) (according to the liner notes) (everyone know what liner notes are/were?). I suppose one more of Brubeck's might help you understand why there are time signatures: \"Blue Rondo a la Turk\", in 9/8, where he organizes it as 3 measures of ONE-two-*three*-four-*five*-six-*seven*-eight-nine, then a measure of ONE-two-three-*four*-five-six-*seven*-eight-nine. The band switches back to a 4/4 stomping blues in the middle, and alternates a bar (4 measures, I think) of one with a bar of the other before finishing up. I guess the short answer to your question is that the different time signatures change the rhythm of the music and generally indicate speed, though of course that's variable. All of the above are available on the \"Dave Brubeck's Greatest Hits\" album.",
"Adding to what /u/drafterman said: 4/4 is common time, along with 2/4 and 3/4. The bigger the number, the faster the beat. So sixteenth notes are noticeably faster than quarter notes. This is because it is being subdivided. Think of a pizza slice. It's cut in half multiple times. Also, 6/8 and 7/4 can be subdivided different ways. For 6/8 you can have 3 + 3 = 6, or 4 + 2 = 6, or 1 + 5 = 6. The same for other odd time signatures.",
"Fuck it, I'll give it a try. Music is an arrangement of sounds in time. Much like objects are arranged in a space. For you to know where things and places are, you must adhere to a certain measurement, like meters, miles, bananas, etc.... You know that the table is about 4 feet from the wall and 6 feet from the door in the first room to your right as soon as you come in through the garage. When sending your friend in to put groceries on the table, you tell him this and expect to find your groceries on the table. In the same way, we know that a certain note is played at a certain beat in a measure. EX. In two 4/4 measures: | G - G - G - G | G - G - G - A | You tell your grocery carrying friend that you play 2 bars of G with an A on the 4 of the second measure. Then you expect to find that A on the 4th beat of measure 2, much like your groceries. But not all places are alike, and not all measurements the same. When giving directions to your house you don't use feet, or distance from walls etc. you use larger measurements like Miles, kilometers, blocks, parks. Like in Savannah Ga they have little parks called squares every few blocks throughout the city. When giving directions there, you say. \"Start at the toilet paper roll (a real landmark) going towards the river it's the second house on the right, on the second block after the second square.\" Just like Savannah, some melodies don't naturally adhere to the 4/4 meter. Maybe they have some middle eastern influence, maybe the were written under the influence. But these require a different measure (signature) So in this song you have a certain note at a certain point in time: EX. Two measures in 5/4 time | G - G - G -G - G | G - G - G - G - A | You tell your Savannah wanderer friend that we are in 5. And you play two bars of G with an A in the 5th beat of measure 2. When you play you expect that note in that specific place in time, much like your friend visiting you in Savannah. Most western modern music has evolved to use mostly 4 beats per bar. But not all music naturally has this time signature. When you see a group of good musicians on stage you can assume they are all counting in their head in some form or fashion. They are all counting the number of beats in the bar in order to stay together. A snippet of my train of thought when performing, for example: \"Ok dude, don't fuck it up... here we go... 1234 G 234 F 234 A2G4 slide 234 stop 234 1234 1234 BOOM 234 soft 234 A234 GFDB C234 ... \" In case of a song in 5 I'd be counting to 5 etc... there is even music that has 13 and 15 beat measures like the Xoro in Bulgaria. It's folk music and PEOPLE DANCE TO IT!!!",
"It tells you how many beats there are in a measure and what note determines the beat. We typically think that a quarter note is one beat, but in a time like 6/8, it is actually two beats. This is because the top number 6 is how many beats there are, and the 8, or \"eighth note\" determines the beat, and a quarter note is two eighth notes. And no, not all notes have to eventually come back to an even number. Dotted notes exist, which makes a note 1.5 times as long, so a dotted quarter is actually 1 quarter and 1 eighth note. These are not to be confused with staccato marks, which appear on top of the note and denote how the note should be articulated. The reason why we use these formats instead of writing everything down in 4/4 is that certain rhythms and styles are more easily interpreted when written as such. For instance, 6/8 is typically counted in twos. This can create a bouncy feel and creates a folk sounding tune. Other times, it's because a musical phrase is that long. (I believe the Doctor Who theme has a 7 beat phrase). In this case, the bars are just made longer. There are also many other forms of time signatures like cut time, which is written as 2/2, which from what has been explained before means that there are 2 beats in a measure and the half note (1/2, or 2) determines the beat.",
"Try reading this explanation on prog metal time signatures. It's broken down in a simple to digest format. URL_0 Edit: Music is really just chopping up time with different pitches and sounds into a pleasant pattern.",
"The bottom number of a key signature is usually which kind of note gets the macro (or \"big\") beat. 4 is quarter note, 8 is 8th note, 16 is 16th note, and 2 is half note. The top number is how many of those notes you can expect in a measure, or the subdivision. 4/4 is four quarter notes in a measure. 6/8 would be 6 eighth notes in a measure. 5/16 would be 5 16th notes per measure. The grouping or feeling of those beats would depend on the piece of music itself. (For example, 5/16 could be 2 of 16th notes felt as a macro beat, then 3 groups of 16th notes or vice versa) 7/4, by this logic, would be 7 quarter note per measure. Hope this helps!",
"It's really about the easiest way to divide up the feel of the music into notation for the sake of writing and reading and working together. Anything in 4/4 can also be written in 2/2 or 8/4. The proper terminology is that the top number designates how many beats are in each measure, and the bottom number designates which kind of note counts as one beat. 4/4 time means each measure is made up of 4 quarter notes. If you take music written in 4/4 and just change the time signature to 2/2, it would be played exactly the same. The only difference would be the conductor would then waive their arms around only half as fast as before. Something like 7/8 is simply counting measures consisting of 7 8th notes. It can be difficult to get the feel of playing at first, but once you get the hang of it, can be really fun."
],
"score": [
11,
8,
7,
6,
5,
3,
3,
3
],
"text_urls": [
[],
[],
[],
[],
[],
[
"https://www.ultimate-guitar.com/lessons/songwriting__lyrics/how_to_write_progressive_metal_-_parts_8-9_odd_time_signatures_and_polymeters.html"
],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7gjble | why can't the big companies like google deny service to non neutral ISPs | Technology | explainlikeimfive | {
"a_id": [
"dqjie9b"
],
"text": [
"> wouldn't the customers go to other isps Oh sweet summer child. Much of the problem lies in the fact that people don't have other ISPs serving their area."
],
"score": [
9
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gjcap | How can an infant go from breast milk to formula with no problem | Biology | explainlikeimfive | {
"a_id": [
"dqjihym"
],
"text": [
"you know formula is called formula because it is specifically formulated to imitate breast milk right?"
],
"score": [
3
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gjckf | How do wholesale power companies know at what time you use electricity? | Other | explainlikeimfive | {
"a_id": [
"dqjjh3s",
"dqjltfm"
],
"text": [
"Older electricity meters can't tell - but they've all been replaced, in most cases by wi-fi or cellular meters that keep a full log of times and amounts used. If you ever see a guy driving a truck or car slowly through your neighborhood (or your neighborhood HOA freaks out about one) there's a good chance he's from the electric company and is driving around wirelessly collecting everyone's monthly bill info. So the answer is that it's trivial to keep a time log in any electric meter installed in the last 30 years.",
"Ask your power company, or local utilities regulatory agency what features are enabled in the \"smart\" meter and if you have one installed at your residence."
],
"score": [
4,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7gjft0 | Why is there turkey bacon but no chicken bacon? | Other | explainlikeimfive | {
"a_id": [
"dqjk9bx"
],
"text": [
"Bacon is, by definition, strips of cured meat from the belly of a pig. Turkeys aren't pigs, so there's actually no such thing as turkey bacon. Turkey bacon is pseudo-bacon. It is an abomination."
],
"score": [
17
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gjkk2 | How are games like Fallout: New Vegas only 5.5 GB and games that are way less content like Call of Duty take ~70 GB? | Technology | explainlikeimfive | {
"a_id": [
"dqjl29c",
"dqjlaeu",
"dqjl35w"
],
"text": [
"Because one is an AAA game with lots of unique full motion video (which your computer couldn't render on it's own) and the other is made by an almost-indie company with hordes of repeatable low-poly models that all use the same hundred textures. It really doesn't take much CPU or hard disk space to render a giant landscape with a few textures. It's much more expensive to render it on a supercomputer(literally) to make it as pretty as possible then store the video on your computer. TL;dr AAA games use videos which take up lots of disk space, smaller games don't",
"Call of Duty often uses stuff once then never uses it again. Fallout takes something it used before and uses over and over again in different circumstances. So the total amount of stuff *in* CoD is more, while the each thing in Fallout is used more. Also the things used in FO:NV are smaller than each thing in the new CoD. Less details means less space.",
"It's mostly graphics that take up the majority of storage space in games nowadays, and Call of Duty is a game that banks heavily on graphics whereas Fallout: New Vegas is not so much."
],
"score": [
6,
5,
3
],
"text_urls": [
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7gjtt7 | In developing countries, everyone (including visitors) uses dishes washed with non-potable water and washes their hands/showers in non-potable water with seemingly no ill effects. If they drink it, however, they nearly always get sick. What explains this paradox? | Biology | explainlikeimfive | {
"a_id": [
"dqjmu5k"
],
"text": [
"Even in developed countries, tap water will have some pathogens in it. Treated municipal water or even bottled water is not sterile, it's sanitized to a safe level. The goal is to treat the water down to a level where the harmful bacteria, viruses, protozoa, etc are at a concentration where your body's immune system can handle it. In theory, a dish washed, hand washing, bathing, tooth brushing all exposes you to a small amount of pathogens, a level at which your body can most likely fend it off with out issue. Someone with a compromised immune system might get sick. Drinking that same non-potable water significantly increases the odds because of the volume of potential pathogens ingested. Finally, hopefully the washed dishes are at least air dried, so any water borne pathogens will have died before food is placed on it."
],
"score": [
4
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gjv8o | Why are B vitamins clubbed together ? | Biology | explainlikeimfive | {
"a_id": [
"dqjmod4"
],
"text": [
"Yer not alone in askin', and kind strangers have explained: 1. [ELI5: why are there so many B vitamins and not others? ]( URL_0 ) 1. [ELI5: Why are there so many B vitamins? ]( URL_4 ) 1. [ELI5: Why are there so many different \"B-vitamins\" ]( URL_3 ) 1. [ELI5: What makes a B Vitamin a B Vitamin? ]( URL_1 ) 1. [ELI5: vitamin letters and numbers like B6 B12. ]( URL_2 ) 1. [ELI5 why the vitamins are named like they are. Why do we have 12 Vitamin B's but no Vitamin J? Is there a Vitamin B9? ]( URL_5 )"
],
"score": [
5
],
"text_urls": [
[
"https://www.reddit.com/r/explainlikeimfive/comments/5kedrn/eli5_why_are_there_so_many_b_vitamins_and_not/",
"https://www.reddit.com/r/explainlikeimfive/comments/3s6wku/eli5_what_makes_a_b_vitamin_a_b_vitamin/",
"https://www.reddit.com/r/explainlikeimfive/comments/1mmsw0/eli5_vitamin_letters_and_numbers_like_b6_b12/",
"https://www.reddit.com/r/explainlikeimfive/comments/2glirs/eli5_why_are_there_so_many_different_bvitamins/",
"https://www.reddit.com/r/explainlikeimfive/comments/4oaulc/eli5_why_are_there_so_many_b_vitamins/",
"https://www.reddit.com/r/explainlikeimfive/comments/qeuc7/eli5_why_the_vitamins_are_named_like_they_are_why/"
]
]
} | [
"url"
] | [
"url"
] |
|
7gjz3n | Why does rain not hurt when it hits you, even though it falls from an average height of 2 kilometers (around 6500 feet)? | I was wondering why rain doesn't hurt when it falls on you from such a large height. I was thinking if I were to drop other objects of equal size from this same distance it would definitely hurt. Thank you! | Physics | explainlikeimfive | {
"a_id": [
"dqjnhjf",
"dqjnhtp",
"dqkcnm1",
"dqk5ke2",
"dqjp6a1",
"dqjpjlw"
],
"text": [
"every object falling through the air has a terminal velocity based upon air density, object density, and frictional forces. A drop of water weighs so little, and falls through the air at relatively low speeds, that it hardly has any force behind it at all.",
"The increasing drag from air resistance keeps the small drops from gaining speed once they reach a certain speed, known as their *terminal velocity.* For raindrops this is about 10 m/s or about 20 mph.",
"Holy shit imagine how humanity would live if rain fucking hurt. We'd be fucking mole people. In all the infinite universes, there's probably one without terminal velocity. All cities underground, probably no war because cultures with harsh environments are usually more peaceful. Huh. I love thinking about weird shit. Thanks for this one, reddit lol",
"Interestingly enough, rain stings like little needle pricks while riding my motorcycle without a helmet, at low speeds. ( < 35mph).",
"If you drop a cotton ball off a building it still won't hurt anyone. A drop of water has very little mass and very little surface tension so it just disintegrates",
"Short Answer: Terminal velocity, rain droplets are very light so it dose not take a lot of drag to slow them down to a soft speed. The Complex Answer: Drag is calculated using this formula: D = Cd * A * .5 * r * V^2 Notice that V^2 that's velocity squared, or Velocity x Velocity, so drag increases rather quickly the faster you move. The rest of the formula is: Drag is Equal to the Coefficient of drag (shape of the object) x Cross sectional area x One half the Density of air times Velocity Squared. As the droplet falls, that drag increases and hits a point where it is equal to the pull of gravity, so they cancel each-other out at a velocity known as \"Terminal Velocity\". That speed is a function of Three values, Coefficient of drag, Cross sectional area, Mass of the object. Since water droplets are round they have a high drag coefficient, also water is rather light. All things calculated out it's speeds are not that high. Note: Technically density is the factor we care about regarding mass and objects of equal shape but it's a bit more straight forward when you think about it as mass."
],
"score": [
47,
5,
5,
3,
3,
3
],
"text_urls": [
[],
[],
[],
[],
[],
[]
]
} | [
"url"
] | [
"url"
] |
7gk1o3 | Why are standard "homemade" water filters made of gravel, soil, and charcoal as opposed to just charcoal. What does the gravel and soil do that the charcoal doesn't? | Chemistry | explainlikeimfive | {
"a_id": [
"dqjo2zf",
"dqjo1ic",
"dqjp6gn"
],
"text": [
"Even municipal water treatment facilities frequently use sand or gravel as part of their filtration process. Sand/gravel is used to filter suspended stuff in the water, like mud, leaves, etc. Charcoal filters are used to filter smaller particles that may change the taste of the water. Think of the sand as a pre-filter. URL_0",
"Filters out larger contaminants before the charcoal. Sure the charcoal could be okay, but there is a lot of bigger crap in natural/outdoor water, the rocks and soil help filter those things. Otherwise your charcoal will get clogged really really fast.",
"Because sand and gravel do a good job of filtering things. I mean as something passes through sand, lots of things that aren't water don't survive that process. You aren't going to get the microbes out, but you can get lots of tiny bits of things that don't belong in water. Or well things that belong in water, but that you don't want to drink."
],
"score": [
10,
5,
4
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/Slow_sand_filter"
],
[],
[]
]
} | [
"url"
] | [
"url"
] |
|
7gkfqk | Why does the color of an object fade after being exposed to sunlight for a long period of time? | Chemistry | explainlikeimfive | {
"a_id": [
"dqjqsov"
],
"text": [
"Ultraviolet radiation can have a damaging effect over time; breaking down the pigments and dyes used to color materials."
],
"score": [
9
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gkw3b | How do salted roads help prevent slipping? | Chemistry | explainlikeimfive | {
"a_id": [
"dqjtafe"
],
"text": [
"Salt melts ice by mixing with the water on the ice surface, which creates a brine. This slightly lowers the freezing point of the water, which causes the ice below to melt (as long as the ambient air temperature is above about -10C/15F). It can also provide traction on icy surfaces by increasing friction."
],
"score": [
6
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gl3w6 | Why do wheels sometimes look like they're spinning in the wrong direction? | Physics | explainlikeimfive | {
"a_id": [
"dqjuq0y"
],
"text": [
"Much like film, human eyes see in 'flashes' as parts on the inside of the eye are struck by light, send the still image to your brain, and then reset for the next image. This happens many times each second, but it means that your brain is still just getting a bunch of still images from your eyes. Your brain puts them together as best it can, as quickly as it can, and fills in the gaps to make it seem like you're getting a constant stream of visual input. However, for fast moving things like hubcaps, and especially propellers, the images your eyes send can make it look like they're moving slowly, or backward, or even not at all, depending on their speed of rotation."
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
|
7gl3y7 | How does sanding and polishing things makes them shiny? | Hey, so I was just watching some carpentry videos, and have sanded and polished things in the past, but dont think I ever knew why is this process making the objects more clear/shiny. ELI5 :) | Physics | explainlikeimfive | {
"a_id": [
"dqjv8zb"
],
"text": [
"This is neatly illustrated by grabbing a piece of aluminum foil. At first, the aluminum foil is 'polished'. It's smooth and has a very even surface, allowing you to see stuff reflected in it. But crumple it up, then straighten it out again, and you're not going to see diddly-squat in it anymore. Polishing does quite the opposite. Most 'randomly generated' (by nature, or biological growth, etc) surfaces will typically be quite rough and bumpy on a microscopic scale. Every surface reflects light to some degree, or you wouldn't be able to see it at all. But most surfaces will typically throw the image of something that comes at it all over the place, because every one of those microscopical bumps will cause the light to be reflected in another direction, depending on its angle to the incoming light. By polishing something, you smooth it out - you remove those tiny hills, bumps and uneven bits across its surface, smoothing it out. This way, much more of the light coming from something will be reflected evenly in the same direction, and you'll have a much more visible and discernible reflection, and thus, make it more shiny."
],
"score": [
11
],
"text_urls": [
[]
]
} | [
"url"
] | [
"url"
] |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.