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What is the oldest known human structure? | Before about 10,000 years ago the evidence for human-built structures is very scarce. But that's not because people weren't building things, it's because they were building them exclusively out of fragile organic materials like wood and so, unlike stone, clay or mud brick structures, they aren't going to survive for ar... | [
"The oldest complete human skeleton (renamed \"Amsicora\") was found in 2011 in the territory of Arbus, it dates back to about 9,000 years ago, the period of transition between the Mesolithic and the Neolithic.\n",
"The oldest extant structure is the Jambhala Lhakhang which was originally built under Ralpacan. It... |
how can we use telescopes to see into the far reaches of space, generating massive resolution images, yet we have to send a spacecraft like dawn to see a white spot on ceres? | The things that we can see far away are **very** big and **very** bright.
You can easily see a billion burning candles arranged on a hilltop miles away in a pitch-black night (seeing another galaxy filled with billions of stars), but good luck seeing a discolored spot on a grain of sand 10 feet away by the light of a ... | [
"The space telescopes were to observe in the infrared part of the electromagnetic spectrum. As well as studying extrasolar planets, the telescopes would probably have been useful for general purpose imaging, producing very high resolution (i.e. milliarcsecond) infrared images, allowing detailed study of a variety o... |
Is it possible to observe the process of a star becoming a black hole? | You're most likely to see a regular supernova and that's it. Black holes are not visible so without any special equipment you wouldn't even know it's there when it forms only it's interactions to other objects can be detected. | [
"A black star with a radius slightly greater than the predicted event horizon for an equivalent-mass black hole will appear very dark, because almost all light produced will be drawn back to the star, and any escaping light will be severely gravitationally redshifted. It will appear almost exactly like a black hole... |
what do we know about what goes on inside of other planets in our solar system? | Not a whole lot of direct study. We can make some measurements - for example, we know their mass and size, so we can calculate their density, which tells us something about what they're made of. Saturn, for example, is very light - less dense than water - so it can't have much of a solid core, if it has one at all. Ear... | [
"The image below-left features the \"inner\" planets: their orbits, orbital nodes, and the points of perihelion (green dot) and aphelion (red dot), as seen from above Earth's northern pole and Earth's ecliptic plane, which is coplanar with Earth's orbital plane. From this orientation, the planets are situated outwa... |
- where do "royals" obtain their original claim of "royalty" from? | From stabbing people with swords who disagreed. | [
"With the exceptions of the dukedoms of Cornwall and Rothesay (which can only be held by the eldest son of the Sovereign), royal dukedoms are hereditary, according to the terms of the letters patent that created them, which usually contain the standard remainder to the \"heirs male of his body\". The British monarc... |
How does the monarch butterfly change its lifespan between generations? | Several things to consider here :
* First of all, the genetic information doesn't say "that individual will live this long", it's more like the lifespan depends on many other genetic traits. That means it's not genetic information changing form a generation to another. At most, the phoenotype changes (that the express... | [
"An adult butterfly emerges after about two weeks as a chrysalid, and hangs upside down until its wings are dry. Fluids are pumped into the wings, and they expand and stiffen. The monarch expands and retracts its wings, and once conditions allow, it then flies and feeds on a variety of nectar plants. During the bre... |
The "germ theory of disease" Wikipedia page suggests that germ theory had many antecedents (people talking about "pestifera semina") going back to antiquity. Why was miasma theory popular as of the 19th century? | I've been meaning to write an answer to your question since you posted it, but I didn't get around to actually writing it. Well, I hope that you're still waiting for an answer.
I have a few problems with the history-sections of that Wikipedia page. The most basic would be that it doesn't paint a good picture of the m... | [
"Germ theory's stance that the \"germ\" was the disease's \"necessary and sufficient cause\"—the single factor both required and complete to result in the disease—proved false. Germ theory gradually evolved to include other factors, whereupon germ theory resembled miasmatic theory, which had had to recognize bacter... |
What prevents the intestines from tangling themselves like my headphone cords? | Dentist here. We concentrate on the teeth, but we do study the whole body in pretty gross detail.
The short answer to your question is that the intestines are attached to several different connective tissues, particularly mesentery and omentum. Mesentery is a very stretchy connective tissue that loosely holds the inte... | [
"Intestinal decompression by tube placement in a small stoma can also be used to reduce distension and pressure within the gut. The stoma may be a gastrostomy, jejunostomy, ileostomy or cecostomy, and may also be used to feed, in the case of gastrostomy and jejunostomy, or flush the intestines.\n",
"In human anat... |
antitrust lawsuits | Let's say you have two companies selling apple. Now both companies will sell apples at a good price, let's say that price is $1 an apple. If ether company was to raise their price then they'd sell less apple cause who would want to buy an apple for $1.50 if they could buy an apple for dollar.
One day the head of one c... | [
"Anti-trust law is the body of laws that exist in order to prevent companies from suppressing market competition from other companies. The Sherman Antitrust Act was a landmark piece of federal legislation passed in 1890 and \"intended to prevent all contracts, combinations, and conspiracies which restrain or monopo... |
why can't we recreate dinosaurs just like in jurassic park? | To create clones you need to take the nucleus of a cell of one animal and place it in an egg without a nucleus of the same species. This is then given to the female and is grown in the normal fashion. Blood (in human's certainly) tends not have cell nuclei, hence it wouldn't be possible for humans. Even if you were ... | [
"While \"Jurassic Park\" featured mostly the animatronic dinosaurs built by Stan Winston's team, \"The Lost World\" relied more on the computer-generated imagery of Industrial Light & Magic. This meant the film featured larger shots that offered plenty of space for the digital artists to add the dinosaurs. Although... |
sd cards | You are right the plastics bits and the copper contacts that make up moth of the SD card that you can see have a negligible price. They are not worth much.
The actual flash memory itself inside the card is what makes up most of the price. It consists of stuff like silicone and metals and other stuff that doesn't seem ... | [
"Most SD cards ship preformatted with one or more MBR partitions, where the first or only partition contains a file system. This lets them operate like the hard disk of a personal computer. Per the SD card specification, an SD card is formatted with MBR and the following file system:\n",
"Like other types of flas... |
if a bank goes out of business and i happen to have a mortgage with said bank, what would happen? | They would sell your debt to someone else as a way of paying off their debts, and now you owe your mortgage to some other entity. | [
"The banks thereafter began to issue mortgage loans with CMHC underwriting. If the individual receiving the loan went bankrupt then the bank who gave the loan would not lose money, but instead would be reimbursed by the government. As part of CMHC lending and insurance mechanisms, low-risk borrowers would have to p... |
Are planets exclusively formed after stars from the remaining material, or are there other natural ways we've observed/theorized planet(s) forming? | Technically speaking a planet is defined as an object orbiting a star, though this gets a bit problematic when considering rogue planets that have been ejected from their stars.
The same process that leads to star formation--collapse of cloud of gas in a nebula--can sometimes fail to collect the critical mass necessar... | [
"It is not known with certainty how planets are formed. The prevailing theory is that they are formed during the collapse of a nebula into a thin disk of gas and dust. A protostar forms at the core, surrounded by a rotating protoplanetary disk. Through accretion (a process of sticky collision) dust particles in the... |
Resources for Medieval Church/Choir Music | The answer sort of depends on exactly what you're looking for. Most of the music used in video games and movies is composed recently, it's not authentic medieval music. They get the same sound by using a lot of open fourths and fifths, but real medieval music would sound horribly boring in a modern video game. If yo... | [
"The Digital Image Archive of Medieval Music (DIAMM) is a non-profit academic service provider. It is the only complete listing of all medieval and early modern manuscripts of European polyphonic music. It is founded on a digital archive of images of European medieval and early modern polyphonic music ranging from ... |
What did the people of the Spanish peninsula look like before the Moors arrived? | Hi there! So if we're talking about what they "looked like" I'm assuming you meant in terms of their actual physical appearance. The short version is that there was an array of people and cultures in Iberia and their appearances varied accordingly. The racialist myth of "the white iberians before the moors turned up!" ... | [
"The Moors ruled southern and eastern Spain until the 11th century \"reconquista\" (reconquest). Alicante was finally taken in 1246 by the Castilian king Alfonso X, but it passed soon and definitely to the Kingdom of Valencia in 1298 with the Catalan King James II of Aragon. It gained the status of Royal Village (\... |
the difference between poisonous and toxic things | The term poison refers to any substance that is harmful to your body if consumed. Toxin is a specific branch of poison, defining naturally created poisons. For example, many household cleaning substances are poisonous, but are artificially made and are not toxins.
Here is the Article my information came from: _URL_0_ | [
"Some poisons are also toxins, which is any poison produced by animals, vegetables or bacteria, such as the bacterial proteins that cause tetanus and botulism. A distinction between the two terms is not always observed, even among scientists. The derivative forms \"toxic\" and \"poisonous\" are synonymous. Animal p... |
If there was no oxygen and paper was heated to a super high temperature, would it melt not burn? | Yes. There couldn't be any chemical reactions, and if you reach the necessary temperature it will break down into its parts. That would happen around 250° celsius temperature. You would be left with charcoal and hydrogen gas. | [
"Because of its cryogenic nature, liquid oxygen can cause the materials it touches to become extremely brittle. Liquid oxygen is also a very powerful oxidizing agent: organic materials will burn rapidly and energetically in liquid oxygen. Further, if soaked in liquid oxygen, some materials such as coal briquettes, ... |
If I continuously shot charged particles into a black hole, what would happen over time with the buildup of charge? | Assume a nonrotating black hole.
Now start pissing electrons into it. First, it'll gain mass as the electrons cross the event horizon, with the radius of the event horizon now steadily increasing. The electrons end up smooshed together at the singularity- the crushing forces inside the black hole are irresistible. The... | [
"The maximum amount of energy gain possible for a single particle via this process is 20.7%. The process obeys the laws of black hole mechanics. A consequence of these laws is that if the process is performed repeatedly, the black hole can eventually lose all of its angular momentum, becoming non-rotating, i.e. a S... |
how did futurama win 6 emmys but got canceled twice? | Being a good show doesnt mean a lot of people like it. A show may have great acting, amazing plot, good dialogue, etc., but the genre/premise/etc. may just not interest people. My father doesn't take animation seriously, he would never watch Futurama, no matter how much he would like it if he did.
There are a lot ... | [
"\"Futurama\" executive producer David X. Cohen referred to this episode as \"Futurama\"'s lost episode due to the delays in its initial broadcast. Fox Network decided the episode was not appropriate for its 7 p.m. time slot (due to the one use of strong language and scenes of violence, though, according to the DVD... |
why is the letter the 47 republican senators sent to iran today such a big deal? | Essentially the Republicans are telling Iran that any nuclear agreement made with the Obama administration will be deemed null and void after the next US election (presumably if the Republicans win a majority).
What is so serious is that The Republicans are trying to undermine the government in the most flagrant and n... | [
"Three times elected a delegate to the Republican National Convention, Simmons gave the second to the nomination of Herbert Hoover as candidate for the President of the United States at the 1932 convention. According to a report in the \"Pittsburgh Courier\" the day after the nomination, \"his exit from the platfor... |
how do companies like gm and apple quickly pivot to making new products like masks and ventilators? | I think it’s not so much that they switch to manufacturing masks and ventilators, they just have them already and are donating them. At least for apple and other big tech companies, their factories are big clean rooms, so they have plenty of masks already. | [
"An artificial lung (AL) is a prosthetic device that provides oxygenation of blood and removal of carbon dioxide from the blood. The AL is intended to take over some of the functionality of biological lungs. It is different from a heart-lung machine in that it is external and designed to take over the functions of ... |
what would happen in the usa if someone tore a ligament (such as acl) and didn't have health insurance? | You would have to pay out of pocket. Usually if you don't have insurance, you may be able to negotiate the costs with hospital to lower the amount due.
Generally, hospitals will charge more for procedures and hospital stays if a patient's insurance company is being billed. Hospitals will never receive the full amount... | [
"The Anterior Cruciate Ligament is the ligament that keeps the knee stable. Anterior Cruciate Ligament damage is a very common injury, especially among athletes. Anterior Cruciate Ligament Reconstruction (ACL) surgery is a common intervention. 1 in every 3,000 American suffers from a ruptured ACL and between 100,00... |
why do people who have sex in movies/shows smoke after it? | It's TV trope, but based on reality. Back when I was a smoker the most enjoyable cigarettes were after sex, after a good meal, and when drinking. | [
"Using pornography has also been associated with frequent sexting. Young people may view sexting as a means of verbal or emotional communication amongst each other, rather than a means of sharing sexually exposing images of themselves to others. Young people, particularly young girls, may feel pressured to send int... |
What is happening in a black hole? Do we have fusion of heavy elements? Could they eventually super nova? | To answer your last question first: no, a black hole cannot supernova. Once matter is inside its event horizon, it's in there for good. It appears, by using quantum physics to study black hole event horizons, that they can emit radiation (called Hawking radiation) which, over time—a very, very long time—can eventually ... | [
"Steinhardt, Spergel and Jason Pollack have proposed that a small fraction of dark matter could have ultra-strong self-interactions, which would cause the particles to coalesce rapidly and collapse into seeds for early supermassive black holes.\n",
"Not all supernovae are triggered by runaway nuclear fusion. Type... |
please explain fetal alcohol syndrome (many more-specific questions herein) | Wow. Four months ago. Still, I think I can add a bit to this, and hope you will see it.
My mother has grown up with FAS. I don't expect anyone in her family would admit it, but she has the classical facial features (you are probably acquainted with these now, but if not, google fetal alcohol syndrome features or signs ... | [
"Fetal alcohol spectrum disorders (FASD) is a term that constitutes the set of conditions that can occur in a person whose mother drank alcohol during the course of pregnancy. These effects can include physical and cognitive problems. FASD patient usually has a combination of these problems. Extent of effect depend... |
what is nsa doing with my information? | Most likely, absolutely nothing. Your information is sitting on a server somewhere, and will not even be read before it gets deleted, due to there being too much to store.
However, this isn't defending the NSA's actions. Let's say a nice middle eastern man moves into the apartment next to you. The NSA has decided to ... | [
"The Washington Post also reported that the NSA makes use of location data and advertising tracking files generated through normal internet browsing i.e. tools that enable Internet advertisers to track consumers from Google and others to get information on potential targets, to pinpoint targets for government hacki... |
How prevalent was looting by US troops during WWII? | Looting by the US military during World War II fell into several categories, which can broadly be grouped as the 'legal' and 'illegal', even if lines might have blurred at times. First and foremost it can be said that the War Department maintained an official policy, laid out and periodically refined by a series of Cir... | [
"BULLET::::- During World War II, Nazi Germany engaged in looting, particularly by Nazi military units known as the Kunstschutz (\"Art Protection\"). The Soviet Army also operated official trophy brigades to loot Germany and the Eastern European countries occupied by Germany (such as Poland). In Asia, the Empire of... |
how and why we feel the emotion, "boredom" whenever we aren't doing anything? | Well I dunno about you but if I'm not on ADHD meds I feel bored damn near constantly. Like painful, unbearable boredom.
So... in light of that, I'm going to go out on a limb and say when you're sitting around doing nothing your brain is most likely not got a lot of dopamine action going on? And since most brains aren'... | [
"In conventional usage, boredom is an emotional and occasionally psychological state experienced when an individual is left without anything in particular to do, is not interested in his or her surroundings, or feels that a day or period is dull or tedious. It is also understood by scholars as a modern phenomenon w... |
What is the value of Monte Carlo method? Doesn't it just return the expected set of results and variance? | The point is using it to calculate something you don't know.
Say you throw an dart at a random point within a square. Inside the square you've inscribed a circle. 'Hits' are counted within the circle, misses outside it. Geometrically, the ratio of hits to throws will approach π.
So you can determine pi that way. Yo... | [
"Monte Carlo methods provide a way out of this exponential increase in computation time. As long as the function in question is reasonably well-behaved, it can be estimated by randomly selecting points in 100-dimensional space, and taking some kind of average of the function values at these points. By the central l... |
the differences and processes of rom and ram | Rom - read only memory. The chip is programmed once, usually by using a writing voltage that is high enough to “burn” the bits in.
Ram - random access memory. You can read and write to it. Writing doesn’t burn bits in, each bit is just basically a capacitor that temporarily stores a charge. | [
"Since ROM (at least in hard-wired mask form) cannot be modified, it is really only suitable for storing data which is not expected to need modification for the life of the device. To that end, ROM has been used in many computers to store look-up tables for the evaluation of mathematical and logical functions (for ... |
why do car commercial disclaimers at the end always play so fast that you can't even understand what they're saying? | Because the company is legally obliged to include the message but doesn't want to spend ad time that they pay for on legal requirement that doesn't help woth the sales. So they keep it as fast and short as possible. | [
"Some TV and radio commercials are concluded with \"fast talking\", which is barely audible or comprehensible to most. While it is this very message that states all necessary disclaimers and exceptions to the advertisement, it is often stated too fast for the viewer or listener to comprehend. This is often coupled ... |
Historical use of a "gun-blade"? | In 1838, the US Navy commissioned 150 [Elgin "Cutlass" Pistols](_URL_0_) for the South Sea Expedition. More info [here](_URL_1_)
If your uncle had 2 of those, they would be quite valuable. | [
"BULLET::::- Knife pistols with folding blades were popular in England during the mid Victorian era. These were made by Unwin and Rodgers, used black powder and were available in various small calibers. Like the modern Swiss Army knife they contained a variety of tools, from blades to corkscrews, and were often use... |
Why are some pharmaceuticals bounded to an hydrochloride and some to an hydrobromide? | There is a difference in how well the crystals form. Larger ions like larger counter-ions, typically, to make stable crystals. When making the drug you want stable crystals to recover the most product cleanly at the end of the manufacturing process. | [
"In chemistry, a hydrobromide is an acid salt resulting, or regarded as resulting, from the reaction of hydrobromic acid with an organic base (e.g. an amine). The compounds are similar to hydrochlorides.\n",
"Hydrobromic acid is mainly used for the production of inorganic bromides, especially the bromides of zinc... |
During the Medieval period, how often were nobility/knights/etc captured in battle? | Not op, follow.up questions:
How are the nobles/knights/etc generally treated when they were captured? | [
"The rest of the captured knights and soldiers were sold into slavery, and one was reportedly bought in Damascus in exchange for some sandals. The high ranking Frankish barons captured were held for ransom.\n",
"It was often claimed that the nobles faced greater risks than the ordinary soldiers as there was littl... |
radio waves allegedly detected coming from another galaxy. how long ago are they likely to be from? | Radio astronomer checking in:
Yes, radio waves travel at the speed of light (radio waves ARE light, just lower energy than visible light), so the travel time is equal to the distance in light-years. Radio waves from a galaxy 10 million lightyears away will take 10 million years to get to us, or conversely we are now o... | [
"In 1932, American physicist and radio engineer Karl Jansky detected radio waves coming from an unknown source in the center of our galaxy. Jansky was studying the origins of radio frequency interference for Bell Laboratories. He found \"...a steady hiss type static of unknown origin\", which eventually he conclude... |
marginal cost | There are some business costs that don't depend on how productive you are. Even if you produce absolutely nothing this year, you still have to pay for building space and air conditioning and stuff.
But there are some costs that *do* depend on how productive you are. For instance, if you're building shovels, you need a... | [
"In economics, marginal cost is the change in the total cost that arises when the quantity produced is incremented by one unit; that is, it is the cost of producing one more unit of a good. Intuitively, marginal cost at each level of production includes the cost of any additional inputs required to produce the next... |
How do we know for certain that we have found every single naturally occurring element? | Each element is identified by the number of protons in its nucleus. As protons don't occur in fractions you can determine that you have found all the elements in a series by looking for gaps. Since we have a fairly long continuous list of elements from 1 out to around 118 we know we have found all of those elements, ... | [
"The discovery of the 118 chemical elements known to exist as of 2019 is presented in chronological order. The elements are listed generally in the order in which each was first defined as the pure element, as the exact date of discovery of most elements cannot be accurately determined. There are plans to synthesis... |
Did the big bang occur in all directions? I often hear that we can only see 13.?? billion light years before we can't see anymore, but isn't there technically another 13.?? billion light years worth of material beyond the initial bang, just in the other direction? | The misunderstanding here comes from your idea of the "center" if the universe.
There isn't one. Every point in the universe appears to be moving away from every other at the same rate.
The *observable* universe " on the other hand is spherical centered on the earth, because light has only had the age of the universe... | [
"Observations made by Edwin Hubble during the 1920s–1950s found that galaxies appeared to be moving away from each other, leading to the currently accepted Big Bang theory. This suggests that the universe began – very small and very dense – about 13.8 billion years ago, and it has expanded and (on average) become l... |
What is the history of the Smith-Mundt act? Why did congress pass a law banning domestic audiences from hearing material intended for foreign audiences? | If you are at an institution with free access to legal databases, you can get greater depth from the legislative records cited below, but here is what I could dig up from free sources:
The initial 1948 law provides that:
> [USIA publications] shall not be disseminated within the United States, its territories, or pos... | [
"Saia v. New York, 334 U.S. 558 (1948), was a case in which the Supreme Court of the United States held that an ordinance which prohibited the use of sound amplification devices except with permission of the Chief of Police was unconstitutional on its face because it established a prior restraint on the right of fr... |
What is the status of Fredrick Jackson Turner's Frontier Thesis among historians today? Is it still used as an explanation of broader aspects of US historical trends, or closer to something that illuminates how Americans in the early 20th century thought about their own past? | After ninety-five years (or so) of two camps - the Turnerians and the anti-Turnerians - bashing one another, there was something of a collective sigh of relief when the controversy around the Turner Thesis was set aside. Even though it was largely unresolved. The situation was so desperate that one didn't even write th... | [
"Slatta (2001) maintains that the widespread popularization of Turner's frontier thesis influenced popular histories, motion pictures, and novels, which characterize the West in terms of individualism, frontier violence, and rough justice. Disneyland's Frontierland of the late 20th century reflected the myth of rug... |
What was the casualty rate for battles between hoplites in ancient Greece? | Back in the 80s, Peter Krentz gathered all known casualty figures from Classical Greek sources in order to establish a rough average.^1 He concluded that in battles of Greek against Greek, the winner suffered about 5% casualties, the loser about 14%. These numbers are very frequently cited in scholarship. They seem per... | [
"The battle went on for some time and if Diodorus's brief account is accurate, took a high cost on both side before reaching a resolution. In the end the hoplites failed to break through the superior Iapygians which destroyed the combined Tarentine/Rhegian force who fled in different directions, in what Herodotus d... |
- why does water bead up where i wrote on a dirty car, and why does it take so long to disappear? | Oil from your skin and the fact that dust is abrasive when you write with your finger on dust it scratches the paint/ clear coat. | [
"Mud can pose problems for motor traffic when moisture is present, because every vehicle function that changes direction or speed relies on friction between the tires and the road surface, so a layer of mud on the surface of the road or tires can cause the vehicle to hydroplane.\n",
"Puddles commonly form during ... |
why does produce from farmer’s markets cost more than organic produce from a grocery store if the middlemen are removed? | In countries like the USA (where labor is costly), farmer's market stands are not cost-efficient. You have a whole person or two, putting in 4-6 hours of work, just to sell a couple of hundred dollars worth of produce. | [
"Additionally, organic local food tends to be more costly so this is not an appealing option to consumers who are shopping on a budget. Small-scale farmers do not receive government subsidies and are not able to support their business on prices comparable to those of industrial-scale food production, so they must s... |
As previously stated, Soldiers from ancient times were lean and fit, what were gladiators like? | I'm working on finding the source at the moment but, as far as I remember, gladiators were actually kind of flabby.
[Edit]
The Archaeological Institute of America has an article [here](_URL_0_) that covers the research from the Austrian Archaeological Institute's study of gladiator remains.
> Compared to the averag... | [
"There were many different types of gladiators in ancient Rome. Some of the first gladiators had been prisoners-of-war, and so some of the earliest types of gladiators were experienced fighters; Gauls, Samnites, and \"Thraeces\" (Thracians) used their native weapons and armor. Different gladiator types specialized ... |
How did early humans switch from hunter-gatherer to agriculture? | I actually studied this quite a bit in undergrad. The first thing to remember is that it varies by region. There are many independent origins of agriculture around the world and not all of them happened the same way. However, there are many common themes, and a major one is that it's typically not very deliberate.
... | [
"Hunter gatherer culture developed among the early prehistoric era. Evidence traces them as far back as 2 million years ago. As primarily nomadic groups, they valued the idea of kinship; moreover, these kinship focused groups recognized status via age as they viewed their elders as the wise ones from the group. Con... |
whаt nutrіеnts dоеs саrtіlаgе nееd? | The non-essential amino acids proline and glycine are building blocks for cartilage. Your body can synthesize them, but dietary intake from gelatinous meats will likely aid in your body's ability to heal. A study was done which used radioactive dye on gelatin, which was then fed to rats with damaged connective tissue... | [
"An esophageal stent is a stent (tube) placed in the esophagus to keep a blocked area open so the patient can swallow soft food and liquids. Esophageal stents may be self-expandable metallic stents, or made of plastic, or silicone, and may be used in the treatment of esophageal cancer.\n",
"\"trans\",\"cis\"-2,6-... |
if orangutans share approximately 97% dna with humans, why do they look so different than humans? | The other 3%.
And really, they don't look all that different from us. Sure, if you had 100 humans and one orangutan in a room, the orangutan would stand out; but if you had 1000 animals of all types, the orangutan and the human would look practically identical. Squid, cockroaches, snakes, and hummingbirds are all much... | [
"In other words, the considerable observable differences between humans and chimps may be due as much or more to genome level variation in the number, function and expression of genes rather than DNA sequence changes in shared genes. Indeed, even within humans, there has been found to be a previously unappreciated ... |
How different was the culture and language of the Scottish Highlands from that of the Lowlands? | When?
Scotti is the Latin name for the Irish, (or, alternatively, northern Irish) who frequently raided Britain. (Gael comes from Welsh Gwydel which is raider, iirc, akin to Viking meaning pirate or something along those lines)
The Gaels of the north of Ireland set up a kingdom that spread across Antrim and the west ... | [
"Thus, from the end of the 14th century, and certainly by the end of the 15th century, Scotland began to show a split into two cultural areasthe mainly English or Scots Lowlands, and the mainly Gaelic-speaking Highlands (which then could be thought to include Galloway and Carrick; see Galwegian Gaelic). This caused... |
$ vs. ¢ | To avoid ambiguity, although it isn't always the case that the main currency symbol goes in front. In many languages, it goes at the end regardless.
Having it in front is useful for two purposes, however. Firstly, it helps prevent people from adding digits to the front of the number (for example, turning 23.50$ into... | [
"When written in English, the cent sign (¢ or c) follows the amount (with no space between), in contrast with a larger currency symbol, which is placed before the amount. For example, 2¢ and $0.02, or 2c and €0.02.\n",
"The cent may be represented by the \"cent sign\", a minuscule letter \"c\" crossed by a diagon... |
[Astronomy] Is there a correlation between galaxy age and the amount of dark matter in it? | the part of the galaxy that contains dark matter is called the "dark matter halo" and contains the majority of the mass in a standard galaxy. it is really hard to accurately weigh a galaxy and determine the amount of dark matter in it, although for the ones we have weighed, it seems like there is usually more dark matt... | [
"The time following the emission of the cosmic microwave background—and before the observation of the first stars—is semi-humorously referred to by cosmologists as the Dark Age, and is a period which is under intense study by astronomers (see 21 centimeter radiation).\n",
"A later study purports to show that the ... |
what should i be looking for when i'm reading nutrition facts? | The most important fact you need to know: **Serving size**
And also the "Number of Servings" | [
"This is a list of nutrition guides. A nutrition guide is a reference that provides nutrition advice for general health, typically by dividing foods into food groups and recommending servings of each group. Nutrition guides can be presented in written or visual form, and are commonly published by government agencie... |
Is there a correlation between exposure to cold weather and getting viral/bacterial infections? | Also, the search bar on the right-hand side of the screen.
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_URL_6_
| [
"The most common infectious causes are viral followed by bacterial. The viral infection may occur along with other symptoms of a common cold. Both viral and bacterial cases are easily spread between people. Allergies to pollen or animal hair are also a common cause. Diagnosis is often based on signs and symptoms. O... |
why/how does the gas released by freshly cut onions clear the nose and sinuses when ill? | This "gas" (actually a volatile liquid) is called syn-propanethial-S-oxide. It is an irritant that affects the mucous membranes and tear glands to secrete a lot of liquid. This liquid washes out any hardened snot that might be stuck to your mucous membranes. | [
"Eye irritation can be avoided by cutting onions under running water or submerged in a basin of water. Leaving the root end intact also reduces irritation as the onion base has a higher concentration of sulphur compounds than the rest of the bulb. Refrigerating the onions before use reduces the enzyme reaction rate... |
Does alpha decay lead to an ion being made as the atom has lost two protons and so now has two more electrons than protons? | Yes conservation of charge means that the resulting atom will be in a -2 charge state. Generally this state is not stable and the atom will interact quickly with local chemistry in some way to lose that charge. Some smaller atoms may even emit one of the electrons directly without requiring a reaction with local compou... | [
"Alpha decay typically occurs in the heaviest nuclides. Theoretically, it can occur only in nuclei somewhat heavier than nickel (element 28), where the overall binding energy per nucleon is no longer a minimum and the nuclides are therefore unstable toward spontaneous fission-type processes. In practice, this mode ... |
Are there any examples of slavery supporters in the American South who changed their mind and rejected slavery (either before or after the Civil War)? | I have no doubt there will be a great deal of examples that people more familiar with american politics then myself can state but one example would be Rebecca Fleton a georgian feminist who is mostly known for being the first female senator (albeit only for one day as a publicity stunt when she filled her late husband'... | [
"As slavery disputes intensified in the 19th century, there emerged two doctrines within the Methodist Church. Churches in the South were primarily proslavery, while northern churches started antislavery movements. The apologia of the Southern churches was largely based in Old Testament scriptures, which often repr... |
Has a submarine ever sunk another submarine, in any war, ever? | More than a few times. In the Pacific theater, USN submarines sank the Japanese Ro-45 (although this claim is disputed), I-28, I-29, I-73, I-168, and I-183 as well as the *Monsun-Gruppe*'s [U-537](_URL_5_) and [U-183](_URL_8_). _URL_6_ 's [Sensuikan! page](_URL_4_) has the tabular record of movement (TROM) for each of ... | [
"Another eight submarines went missing while on patrol and are presumed to have been sunk by Japanese mines, as there were no recorded Japanese anti-submarine attacks in their patrol areas. The other thirty-three lost submarines are known to have been sunk by the Japanese.\n",
"BULLET::::- On 2 May 1982 the Royal... |
If graphene is a single layer of carbon atoms, how would it conduct electricity? | It’s graphene’s structure that makes it conducive. A given carbon atom shares sigma-bonds with 3 other carbon atoms in the same layer, and pi-bonds with the adjacent layers. This pi-bond (actually pi-band) enables free electron movement, and hence electronic properties (namely conductivity).
When you get down to a si... | [
"Graphite conducts electricity, due to delocalization of the pi bond electrons above and below the planes of the carbon atoms. These electrons are free to move, so are able to conduct electricity. However, the electricity is only conducted along the plane of the layers. In diamond, all four outer electrons of each ... |
can anyone recommend me some eli5-like books on finance/money? | The dummies books are great, they have them on financing and all of those topics you talked about and they'll walk you through how to do those things.
Source: success in several investments from reading those books | [
"His intellectual legacy consists of a trio of highly influential books: Money and Its Uses in Medieval Europe (1988), a groundbreaking study of the role of coined money and credit in the working of the medieval economy; the Handbook of Medieval Exchange (1986), a reference work gathering up all of the then-known d... |
If deleted data can be retrieved, why can't we have our things in deleted state and keep much more space on hard drive disks ? | I think the thing that is confusing you is *what does it mean to be deleted*. When you delete most files on your computer, the OS simply marks those locations as "deleted". This means that future writes to disk might write to those locations. If you manage to "undelete" the content before one of these writes occurs the... | [
"When data is deleted from storage devices, the references to the data are removed from the directory structure. The space can then be used, or overwritten, with data from other files or computer functions. The deleted data itself is not immediately removed from the physical drive and often exists as a number of di... |
Each 10m underwater adds roughly 1atm in pressure. Does that change with liquids other than water? Would it be different in planets other than Earth? | Yes, that is specific to the density of water (d), the strength of gravity on the Earth (g). The pressure is g times d time the height of the column h, so if the density is twice that of water, only 5 meters would be required, and if the gravity were half as strong then 20 meters would be required. | [
"The average value of surface pressure on Earth is 985 hPa. This is in contrast to mean sea-level pressure, which involves the extrapolation of pressure to sea-level for locations above or below sea-level. The average pressure at mean sea-level (MSL) in the International Standard Atmosphere (ISA) is 1013.25 hPa, or... |
when i'm on a cell phone, and i can hear the other person crystal clear, but they say the quality is so bad on their end that they can hardly understand me, what's going on? | Cell towers have more power than a phone, so "tower to phone" is more reliable than "phone to tower". For example, if you are close to your tower and the other person is far away from their tower, they can hear you fine, but their return signal may have trouble reaching the tower. | [
"Some audio quality enhancing features, such as Voice over LTE and HD Voice have appeared and are often available on newer smartphones. Sound quality can remain a problem due to the design of the phone, the quality of the cellular network and compression algorithms used in long distance calls. Audio quality can be ... |
Did the UK ever come close to any serious food shortages in WWII? | Not really.
The Germans had a target of sinking ~300,000 tons of shipping each month in order to starve Britain, and overwhelm British/Allied ship production.
In the first 27 months of the war, Germany only hit that target 4 times. After that, when America joined the war and added their own production to the mix, the... | [
"Before the war Britain imported 70% of its food. Home agricultural production increased 35% during the war. In terms of calories, domestic output nearly doubled. Together with imports and rationing, this meant the British were well fed—they ate less meat (down 36% by 1943) and more wheat (up 81%) and potatoes (up ... |
what does the chipset on a motherboard do and how does it work? | It lets the "brain" of the motherboard - the central processing unit or CPU - talk to all the other components of the motherboard like the memory, peripherals (disk, monitor, keyboard) etc.
If the CPU is the brain of the computer then the chipset is the rest of the central nervous system. | [
"An important component of a motherboard is the microprocessor's supporting chipset, which provides the supporting interfaces between the CPU and the various buses and external components. This chipset determines, to an extent, the features and capabilities of the motherboard.\n",
"The motherboard is the main com... |
do animals feel growth pain? | [They do](_URL_0_), if they have rapid enough growth like larger dogs. Since most of our pets don't have such rapid growth (cat, birds, fish), presumably they don't feel any pain. | [
"According to the U.S. National Research Council Committee on Recognition and Alleviation of Pain in Laboratory Animals, pain is experienced by many animal species, including mammals and possibly all vertebrates.\n",
"Many animals also exhibit more complex behavioural and physiological changes indicative of the a... |
Why didn't Jordan tried to invade Israel in the 1973 war? | It was, at least in part, because the Jordanians had cooperated greatly with the Israelis under Hussein around this time.
Jordan had always been hesitant to attack Israel. In fact, during the 1967 War, the Israelis believed that the fire coming from Jordan initially was just meant to show solidarity; not to inspire fu... | [
"Jordan had entered into a defense pact with Egypt a week before the war began; the agreement envisaged that in the event of war Jordan would not take an offensive role but would attempt to tie down Israeli forces to prevent them making territorial gains. About an hour after the Israeli air attack, the Egyptian com... |
How visually accurate are deep space telescopic images? | I want to begin by saying that that image is most definitely not a real image. It's an artist's conception.
To the naked eye, nebulae look gray. You might seen hints of faint color here and there, but it's mostly just gray. Telescopes use long exposure times and various filters to get their pictures. The light may or ... | [
"The problem becomes less ill-posed when binocular vision allows actual determination of relative depth by stereoscopy, but its linkage to the evaluation of distance in the other two dimensions is uncertain (see: stereoscopic depth rendition). Hence, the uncomplicated three-dimensional visual space of every-day exp... |
What is a soviet? How were they selected? | The soviets themselves were Councils, think of them as political units. You can find a brief essay by Soviet Historian Lewis Siegelbaum on them here: _URL_2_
(It's an excellent site for Soviet History in general, as a side note)
First it is important to remember that there were two Revolutions in 1917. In February,... | [
"Soviets (singular: soviet; , , literally \"council\" in English) were political organizations and governmental bodies of the late Russian Empire, primarily associated with the Russian Revolution, which gave the name to the latter states of the Soviet Russia and the Soviet Union. \n",
"\"Soviet\" is derived from ... |
can you increase the speed of sound by using different gasses? | The speed of sound is increased if the density of the gas is lower. For example, in helium, the speed of sound is 1007m/s at atmospheric pressure and 20°C, almost three times as much as in air. In a heavy gas like xenon, it's only 178 m/s.
That is because the less dense gas is easier to push, while the force created b... | [
"Whenever a gas is forced through a tube, the gaseous molecules are deflected by the tube’s walls. If the speed of the gas is much less than the speed of sound, the gas density will remain constant and the velocity of the flow will increase. However, as the speed of the flow approximates the speed of sound, compres... |
If someone jumped off a cliff as high as the golden gate bridge into a large lake that had a surfactant (soap I guess) poured onto it, would they survive? | Hi, grad student in physics here, I have no experience with surfactants or fluids or how they interact, but i think an elementary analysis using newton's laws will work here.
Consider the moment right before you actually hit the water, you're going at some presumably really fast speed. Then, you hit the water. Now, tw... | [
"Candlewood Lake is home to \"Chicken Rock\", a large rock from which people jump into the water. There is also a rope swing that allows people to swing out over the water. The 25-foot high rock, which projects into the lake from the shore on the Sherman side of the New Fairfield-Sherman border, is the site of freq... |
Can someone explain how those giant single celled organisms on the seafloor are possible? | The membranes are folded and the protozoa are thin, so the cross sectional of the cell would not contain a large amount of fluid. Plus, the entire structure is multi-nucleated.
That solves a number of problems right there.
I would also imagine the membrane contains a different composition of lipids than a normal pla... | [
"Amongst many other living organisms, some gigantic single-celled amoebas with a size of more than , belonging to the class of xenophyophores were observed. Xenophyophores are noteworthy for their size, their extreme abundance on the seafloor and their role as hosts for a variety of organisms.\n",
"Cavalier-Smith... |
According to wikipedia "Current generations of nuclear submarines never need to be refueled throughout their 25-year lifespans" | Naval nuclear reactors use uranium that is enriched to much greater levels than what civilian commercial reactors or research reactors use. U235 levels typically vary between 20% and +95% (weapons-grade, for some subs). This greatly increases energy density of the fuel rods and allows a full lifetime without refueling,... | [
"Current generations of nuclear submarines never need to be refueled throughout their 25-year lifespans. Conversely, the limited power stored in electric batteries means that even the most advanced conventional submarine can only remain submerged for a few days at slow speed, and only a few hours at top speed, thou... |
why progress bars always hang on 99/100% | Progress bar values are basically made up by the developer. For some things they work pretty good. If you are downloading a 100MB file and have finished downloading 70MB then saying you are 70% done is pretty easy. For things like installing a game, where you have a huge number of files of different sizes it gets a ... | [
"The original formula from his book multiple the % with 100 instead of -100. Maybe he has another book/magazine printed it incorrectly and spread out. Nowadays, many software already implemented it as -100.\n",
"The term 80/20 is only a shorthand for the general principle at work. In individual cases, the distrib... |
Why didn't Italy find Oil in Libya while it was an Italian colony. | There were some isolated discoveries during the 1920s that hinted at the possibility of oil deposits in the colony. Wells sometimes produced commercially-negligable amounts of petroleum and natural gas. An Italian geological expedition led by the explorer and geologist Ardito Desio did discover oil in the late 1930s. D... | [
"In 1911, Italy declared war on the Ottoman Empire and invaded Tripolitania, Fezzan and Cyrenaica. These provinces together formed what became known as Libya. The war ended only one year later, but the occupation resulted in acts of discrimination against Libyans such as the forced deportation of Libyans to the Tre... |
About how far away are we from self-powered electronic devices that have batteries that don't need to be recharged? | A battery, by definition, converts chemical energy to electrical energy. This means that, unless chemicals are replaced, or energy is put back into the system, a battery _will_ run out.
You'll find that there are [some designs](_URL_0_) out there that already take advantage of the natural body movement to recharge the... | [
"These batteries could allow electric cars to travel 500 miles before recharging. Replacing the liquid electrodes could only take a few minutes while recharging batteries takes much longer. These batteries don't have the problems of short circuits and overheating. The downsides are that nanoparticles degrade quickl... |
Looking for quotes on American Revolution! Can't quite remember | Try /r/tipofmytongue also | [
"Invoking the American Revolution (it names several prominent revolutionary patriots and quotes the preamble of the Declaration of Independence), and the freeing of the slaves in the American Civil War (there is a brief lyrical and musical quotation of the spiritual \"Go Down Moses\"), as well as Lewis and Clark, t... |
Are sunsets local or global? | Sunrises and Sunsets do vary by where you are on the globe. To start off we can look into why sunsets and sunrises can be red. The blue sky is due to a phenomenon called Rayleigh Scattering. This is were light from the sun is scattered by gases in the atmosphere. These gases preferentially scatter blue light, which... | [
"Sunset is a census-designated place (CDP) and affluent neighborhood in Miami-Dade County, Florida, United States. The population was 16,389 at the 2010 census. The zip-codes serving Sunset are 33173, 33183, and 33193.\n",
"Leek's \"Double Sunset\" on and around the summer solstice also attracts many tourists. Th... |
why don't we have solar powered phones? | Solar panels don't generate nearly enough power. Solar powered calculators only take a tiny amount of power compared to a phone. | [
"BULLET::::- Solar Powered: the advantage of some solar powered units is that they have much more power over their lifetime than battery powered units. This gives them the advantage of reporting their position and status much more often than battery units which need to conserve energy to extend their life. Some wir... |
How different were languages between different Native American tribes? If you could bring together an East coast and West coast tribe, would they be able to mostly understand one another? | The short answer is no.
There are dozens of major language families throughout the Americas. [Algic](_URL_0_) is the only one found on both the east and west coast of North America, and even the handful of small Algic languages in the west have been isolated from their east coast counterparts for thousands of years an... | [
"Most linguists concerned with the native languages of the Americas classify them into 150 to 180 independent language families. Some believe that two language families, Eskimo–Aleut and Na-Dené, were distinct, perhaps the results of later migrations into the New World.\n",
"As the Nisenan (like many of the Nativ... |
why do we use implants for breast enlargement instead of something biological like stomache fat? | Fat is a living tissue. Transplants of living tissue are more expensive and have higher risk of complications. Implants are biologically inert and relatively easy to implant. | [
"A breast implant is a prosthesis used to change the size, shape, and contour of a person's breast. In reconstructive plastic surgery, breast implants can be placed to restore a natural looking breast mound for post–mastectomy breast reconstruction patients or to correct congenital defects and deformities of the ch... |
i want to understand important nutrient information. | Carbohydrates are sweet and starchy things, examples are: sugar, flour, bread, rice, corn, etc.
Fats are oils and greases. If it makes your fingers a little greasy when you touch it, it's probably got a LOT of fat in it.
For weight loss, it's pretty simple. All you want to do is emphasize green vegetables and lean ... | [
"Calculations for nutrient intake can be estimated via computerized software programs that multiply the reported frequency of each food by the amount of nutrient in a serving of that food. References databases commonly used for this purpose are listed below. Note that to estimate total nutrient intake, it is necess... |
how did the uk nhs system work, what did the recent reform bill do to the system and what are the reasons for it? | Okay. Lots of questions and I think I can answer them all relatively simply, at least I'll have a crack and see how I do. If I'm not clear, please ask me again.
> How did the UK NHS system work?
Just to be clear, the bill hasn't come in yet, so I'll answer this for right now. Right now the government gives £105 bill... | [
"The NHS Modernisation Agency was an executive agency of the Department of Health in the United Kingdom. It was established in April 2001 to support the National Health Service in England, and its partner organisations, in the task of modernising services and improving experiences and outcomes for patients. Its fun... |
how do physicists "solve" equations? | It depends on the equation. Note that it is also important to *derive* an equation, that is to come up with one that accurately models or predicts something. The equation you posted is trivial to solve. Take a mass value and multiply it by the speed of light twice. But deriving it, coming up with it, was more diffi... | [
"Solving a simple equation illustrates the basic structure of a structured derivation. The start of the solution is indicated by a bullet (formula_1) followed by the task we are to solve (in this case the equation formula_2).\n",
"The methods for solving equations generally depend on the type of equation, both th... |
Sound of a Baroque Era Classical Pieces sound then then versus now? | It's not that simple.
See, there was [no consensus on a pitch reference](_URL_1_) to the level of precision we discuss these days. There was [eight foot pitch](_URL_0_) and people used whistles and so on to have pitch references, but there was no standard. We start to see that kind of thing in the second half (last de... | [
"The Baroque era was relatively tolerant of bright or extroverted tonal quality, as the surviving pipe organs of the time attest. Thus the Baroque theorist Marin Mersenne described the sound of the cornett as \"a ray of sunshine piercing the shadows\". Yet there is also evidence that the cornett was sometimes badly... |
why do nuclear explosions take the form of a shroom? | It's because of the air rise up. The center of the explosion is really hot, so the air expanses and it become lighter than the cold air above, so it starts rising. Then it drags the cold air around the explosion inside.
When the hot air gets higher, it starts to get cold, it stops rising and spread out like a mushroo... | [
"There are two main considerations for the location of an explosion: height and surface composition. A nuclear weapon detonated in the air, called an air burst, produces less fallout than a comparable explosion near the ground. A nuclear explosion in which the fireball touches the ground pulls soil and other materi... |
Historically, why did England dominate Ireland and not the other way around? | I'm in a History of Ireland course right now, and we've already gone over a lot of the answer for this. England started "dominating" Ireland with the Norman Invasion. The problem with calling it a domination is that an Irish king, MacMurrough, appealed to Henry II for help with problems he was having in Ireland. He ... | [
"It was not until the end of the 17th centuries that the Crown of England gained full control of Ireland by means of a series of military campaigns in the period 1534–1691. During this period, the island was progressively colonised by English and Scottish Protestant settlers. Most of the Irish remained Roman Cathol... |
difference between several types of transistors? | > What is the difference between MOSFET; PMOS, NMOS and BJT's?
FET transistors operate on electrical field, which because you're 5 we're going to just say is the same thing as voltage. Basically, with a MOSFET, it's the *voltage* between "gate" and "drain" that allows (in the case of N-channel) or chokes off (P-chan... | [
"Single transistors are also available in several different surface mount packages, and a number of manufacturers market surface mount packages that incorporate several 2N2222-type transistors in one package as an array of transistors. The general specifications of the various variants are similar, with the biggest... |
Was there a central minting authority responsible for standardization of Roman currency? | There were several dozen mints located around the Empire in various cities, the first and most important of these was in Rome at the temple of Juno Moneta, she was an aspect of the Goddess Juno who was credited with looking after the funds of the city and its populace. The very words 'mint' and 'money' are believed to ... | [
"The original Roman mint network was reorganized and centralized by Emperor Diocletian () at the end of the 3rd century, parallel to the restructuring of the Roman Empire's provincial and fiscal administration. The mints were limited to one per diocese (except for a few exceptions) and placed under the dual control... |
why do we have two lungs instead of one large lung? | Redundancy.
It's an evolutionary advantage to be able to lose one lung, one hand, one kidney, one teste and still function. The energy needed to run two smaller v one large is basically the same.
You hear about people with a collapsed lung living. You don't hear about people with two collapsed lungs living. | [
"Humans have two lungs, a right lung and a left lung. They are situated within the thoracic cavity of the chest. The right lung is bigger than the left, which shares space in the chest with the heart. The lungs together weigh approximately , and the right is heavier. The lungs are part of the lower respiratory trac... |
joint cracking | While still debateded, but we do know that carbon dioxide bubbles form in the joint cavity fluid, which then as you move your joint, would sometimes collapse.
When the bubbles pop, you hear that distinctive pop noise. And bubbles don't form at a moment's notice, it takes time for the bubble to form which is why you ca... | [
"A joint is a break (fracture) of natural origin in the continuity of either a layer or body of rock that lacks any visible or measurable movement parallel to the surface (plane) of the fracture. Although they can occur singly, they most frequently occur as joint sets and systems. A \"joint set\" is a family of par... |
Hi there, could anybody help identify this WWI revolver? | I am afraid that this is going to be a very difficult one to identify, unless there are some markings on it which do not show in any of your photographs. This appears to be a double-action only revolver, with several strange aspects to it. Generally, it appears relatively crudely made, with poor finish work. This, a... | [
"BULLET::::- \"The Voice of the Guns\" (1917) – meant initially to honour British artillery in World War I (hence the name), later it became widely adopted by the British army as a whole. Not to be confused with the poem of the same name by Gilbert Frankau (1916). Featured prominently in the film \"Lawrence of Arab... |
how does augmented reality work? looking for more of the technical aspect. | By sampling a 3D space in the real world using an array of sampling technologies it simply places digital assets within a virtualized space of matching proportions in a convincing manner creating the illusion the object is physically present.
It's just showing the user a digital copy of the environment with assets pla... | [
"Augmented reality is used to enhance natural environments or situations and offer perceptually enriched experiences. With the help of advanced AR technologies (e.g. adding computer vision, incorporating AR cameras into smartphone applications and object recognition) the information about the surrounding real world... |
What was Mexico and Canada's reaction to the American civil war? Were there any foreign volunteers or mercanaires? | **Yes, and in staggering numbers.**
You ask about mercenaries, and let me be clear: Neither the United States nor Confederate States went out to hire foreign mercenaries to fight in the American Civil War on a large scale. There are, however, ample instances in which both the U.S. and C.S. hired foreign soldiers and s... | [
"In May 1942, Mexico declared war on the Axis Powers during World War II, thus officially entering on the side of the Allies. As a result of this, diplomatic relations between Mexico and the UK were re-established. Mexico was one of only two Latin-American countries to send soldiers abroad to fight in World War II ... |
why do elevators decide to wait at the floors they do? | The simplest solution is to have elevators wait whereever they were called last.
Some controllers are smart enough that they can be configured to move empty elevators around to prevent having multiple elevators waiting on one floor, and to minimize the wait time on high-demand origin floors. The exact algorithm var... | [
"Elevators have a car top inspection station that allows the car to be operated by a mechanic in order to move it through the hoistway. Generally, there are three buttons: UP, RUN, and DOWN. Both the RUN and a direction button must be held to move the car in that direction, and the elevator will stop moving as soon... |
how do we not notice rubber on the roads if tires slowly wear down on them? | The tiny grains of rubber leave the road in two ways.
1. They are washed away by rainwater, ending up wherever the drains or ditches near the road lead.
2. They are carried away by the wind. Buildings right near very major roads often end up with a fine layer of rubber and dirt on them. | [
"Off-road tires used in mud or dirt feature individual knob patterns to allow the tire to bite into the surface and lever the sides of the tread to get a better grip. Given the smaller contact patch, these tires tend to wear quickly when used on asphalt (depending on type of rubber).\n",
"It is common amongst dri... |
in every crime show it's a different profession investigating and solving crimes. who actually does it in real life? | When crimes are investigated there are different professions involved.
There are your standard beat cop who is the first to respond. Then there are specialist cops called detectives who are assigned depending on the type of crime. These would be the division that deals with homicides, or in the case of SVU deal with ... | [
"The show takes a \"whodunit\" approach, making each case a mystery that needs to be solved. Every half-hour episode follows one case from its initial investigation until the suspect(s) conviction, acquittal, or some other legal resolution. Pathologists, medical examiners, police officers, detectives, prosecutors, ... |
How did people make coffee in the days before electricity? | Turkish coffee is made by heating a pot of water, coffee, and usually some sugar and spices until it boils and then quickly removing it from the heat source after it's begun to boil. [Here's a video.](_URL_1_)
There's also 'cowboy coffee' which is just throwing the grounds into a pot of water and boiling it together, ... | [
"The history of coffee dates back to the 15th century, and possibly earlier with a number of reports and legends surrounding its first use. The native (undomesticated) origin of coffee is thought to have been Ethiopia.The earliest substantiated evidence of either coffee drinking or knowledge of the coffee tree is f... |
When astronomers say something will happen in x amount if time, to something very far away, do they mean when it will actually happen or just when the light it emits gets to us? | Usually, when talking about future events, astronomers talk about when we will observe that event. So, in your example, in our reference frame, we will observe the star's death 1,000 years from now. However, in the star's reference frame, the event happened 1,000 years ago, and for an observe who is right in the middle... | [
"When one looks out into the night sky, distances also correspond to time into the past. A galaxy measured at ten billion light years in distance appears to us as it was ten billion years ago, because the light has taken that long to travel to the observer. If one were to look at a galaxy ten billion light years aw... |
Mechanics: Mathematically, what is the thought process behind moment of inertia and why is it used in mechanics of materials? | The "moment of inertia" is like mass, but for rotation: it describes how difficult it is to create angular acceleration by applying torque. In this case the result depends on the axis of rotation and direction of the push, not only on intrinsic features of the object as mass does.
Simplest case: if you have a heavy po... | [
"Mechanics, in the most general sense, is the study of forces and their effects on matter. Typically, engineering mechanics is used to analyze and predict the acceleration and deformation (both elastic and plastic) of objects under known forces (also called loads) or stresses. Subdisciplines of mechanics include:\n... |
why is stagnant water unsafe to swim in? | Bad things grow in stagnant water like bacteria and parasites. If you get into the water, there’s a good chance they’ll get into you... | [
"Stagnant water can be dangerous for drinking because it provides a better incubator than running water for many kinds of bacteria and parasites. Stagnant water is often contaminated with human and animal feces, particularly in deserts or other areas of low rain.\n",
"The main criticism of Drownproofing is that, ... |
how do politions who aren't in power get paid? | They are paid for public appearances, become paid lobbyists, do work like writing books or editorials in papers, work for political organizations, etc etc. There are a lot of positions in politics that don't necessarily involve public office.
Edit: In the US at least. | [
"Typically, the payer (an individual, business, or organization) makes campaign contributions to public officials, party officials, or parties themselves, and receives political or pecuniary benefit such as no-bid government contracts, influence over legislation, political appointments or nominations, special acces... |
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