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If you could suggest a single book for someone who wants to learn about the history of the US and US foreign policy what would it be? | [From Colony to Superpower](_URL_0_) by George Herring is pretty hard to beat for a once over of US Foreign Relations. | [
"Foreign Relations of the United States (FRUS) is a book series published by the Office of the Historian in the United States Department of State. The series presents the official documentary historical record of major U.S. foreign policy decisions and significant diplomatic activity. The series began in 1861 and n... |
how do powerstrips stop electric surges? | First, a power strip doesn't stop an electric surge at all. A surge protector does. A power strip is simply adding extra outlets, a circuit breaker, and possibly more reach depending on the length of the cord.
Second, the reset switch (circuit breaker) on a power strip or surge protector doesn't do anything when there... | [
"A power take-off or power takeoff (PTO) is any of several methods for taking power from a power source, such as a running engine, and transmitting it to an application such as an attached implement or separate machines.\n",
"In addition, if overhead electrical power is fed from a trolley pole, the direction of t... |
how is it legal for a parent to smack their child? | Children are not extended the full rights of adults as a necessity for their parents to protect them. A child might be restricted from leaving the house after a certain time, while for an adult that would be false imprisonment. The dividing line between appropriate physical contact in a child's upbringing is a judgment... | [
"In December 2013, in an interview with \"The Independent\" newspaper, Atkinson made clear her personal view that parental smacking of their children should be made illegal. The response by the government was that they had no wish to criminalise parents for issuing a mild smack, while the NSPCC welcomed the commiss... |
why can a computer load a website in about a second but the same website on cell phone takes much longer to load? | Connected to wi fi? 3g? 4g?
What's the age of the phone and the age of the computer? Is your computer a wired connection? How many applications are open on your phone? | [
"Mobile phone users can access and use the same web sites on their wireless handsets that they visit using personal computers. Full web pages load in seconds due to compression and in-network processing of content by the server.\n",
"The first proposed interval between successive pageloads was 60 seconds. However... |
What was the star sized light I saw moving quickly across the night sky? | The international space station is often as bright as the brightest stars in the night sky. It takes approximately 2 minutes to cross the sky above you, depending on your field of view of course. | [
"Some flashes of lambent light, much like the \"aurora borealis\", were first observed on the northern part of the heavens, which were soon perceived to proceed from a roundish luminous body, whose apparent diameter equaled half that of the moon, and almost stationary in the same point of the heavens [...] This bal... |
why do do people cap their fps? isn't more frames = better? | From a brief google search it would seem there are many factors.
Game stability - stable fps is sometimes better than constant oscillation
Heat and other stresses on video cards
Power consumption
Reducing stuttering and screen tearing without using v sync
> Screen refresh rate x 2 + 1. So your 60hz will need a... | [
"Because both film speeds have been used in 25-fps regions, viewers can face confusion about the true speed of video and audio, and the pitch of voices, sound effects, and musical performances, in television films from those regions. For example, they may wonder whether the Jeremy Brett series of Sherlock Holmes te... |
with the volume of dyed fluids i consume, why is my urine only on the yellow -- > clear spectrum? i know the kidney is our organic filtration system but.... where does all the dye go? my fecal deposits are not tye-dye. | Most likely, the dyes break down in your stomach or upper intestine. Most dyes aren't particularly stable molecules, and your digestive tract is designed to break things down. | [
"Pigments excreted in urine are partially absorbed by urate sediments (\" sedimentum latrerium \"), which consists of cell debris and sedimented urinary components formed when the acidified urine is stored below room temperature. These urate sediments looks reddish or pink due to the presence of a main pigment firs... |
Are there any first hand accounts of the British soldiers' journey back to England after the Revolutionary War? | There are very few accounts written by common British soldiers of the American Revolution, and those few that exist are very brief about the trips across the Atlantic. Most are fairly bland accounts that amount to little more than simply stating that the ocean was crossed. Don Hagist has edited a definitive collection ... | [
"In April 1776, on his way to New York City from Boston after his victory in the Siege of Boston, General George Washington camped in the town of Dudley with the Continental Army along what is now a portion of Route 31 near the Connecticut border. During the trip, it is rumored that a \"large cache\" of captured an... |
why do we have to choose between two presidents? why can't we vote for any president who runs? [us] | You could theoretically vote for any of the various presidential candidates who run. Just that the first past the post voting system used by the US punishes you severely for doing so.
For a good example of this, see the 2000 US presidential election in Florida. Many of the more liberal voters chose to vote for Nader ... | [
"In the United States, the President is \"indirectly\" elected by the Electoral College made up of electors chosen by voters in the presidential election. In most states of the United States, each elector is committed to voting for a specified candidate determined by the popular vote in each state, so that the peop... |
Why did Stalin not fully support Mao in the Chinese Civil War? | It was mostly putting pragmatism above ideological goals. Partly, he didn't think Mao would win, and partly, he valued his relations with Chiang Kai-Shek as a buffer between Russia and Japan more than he valued his ideological "allies" in China. Stalin only decided to help Mao when it became clear he'd win.
This kinda... | [
"Stalin privately underestimated the Chinese Communists and their ability to win a civil war, instead encouraging them to make peace with the KMT. Stalin was worried that Mao would become an independent rival force in world communism, preferring a divided China with Mao subordinate to the KMT.\n",
"Westad says th... |
why doesn't chicken, beef, or any other processed meat go through rigor mortis when being prepared at a factory or even in the days afterwards? | Hate to break it to you, but they do.
Rigor mortis, depending on conditions (animal health, size, temperature, etc) takes 2-24 hours typically. In processed meat, it's already in a package by then. Sometimes, the process is allowed to complete, as it can actually result in more tender meat.
When it comes to big anima... | [
"Rigor mortis is very important in meat technology. The onset of rigor mortis and its resolution partially determine the tenderness of meat. If the post-slaughter meat is immediately chilled to 15 °C (59 °F), a phenomenon known as cold shortening occurs, whereby the muscle sarcomeres shrink to a third of their orig... |
Sound waves have never completely made sense to me. Specifically what makes two different sources playing the same note sound different? | I believe what you're talking about is called timbre. Its the result of varying harmonic resonances. A piano playing one note vs. A violin playing the same note sound different because the second and third order harmonics have different amplitudes bases on materials, structure of instrument, etc. I'm sure there is a mu... | [
"If two sounds of two different frequencies are played at the same time, two separate sounds can often be heard rather than a combination tone. The ability to hear frequencies separately is known as \"frequency resolution\" or \"frequency selectivity\". When signals are perceived as a combination tone, they are sai... |
Looking for information about Carthage and the Punic wars for research into a screenplay. | What would you like to know more about?
Here's some global info for you right now:
**TLDR: The Carthaginians left behind tons of stuff. We don't know where it is. Ancient written records are thankfully available. Small caveat, absolutely none of these people like the Carthaginians. There isn't enough salt in the worl... | [
"The historical study of Carthage is problematic. Because its culture and records were destroyed by the Romans at the end of the Third Punic War, very few Carthaginian primary historical sources survive. While there are a few ancient translations of Punic texts into Greek and Latin, as well as inscriptions on monum... |
The American "Rust Belt" seems to be concentrated in one long strip of territory in and around the Midwest. Why didn't industry and factories spring up in the American south in the same way? | Iron ore from Michigan and Minnesota, coal from Pennsylvania and surrounding states, and limestone from Indiana and the Ohio Valley could all be brought to Great Lakes ports inexpensively. Areas near Chicago, Cleveland, and Detroit thus became the center of supply for steel, the primary component of both automobiles a... | [
"The Rust Belt begins in central New York and traverses west through Pennsylvania, West Virginia, Ohio, Indiana, and the Lower Peninsula of Michigan, ending in northern Illinois, eastern Iowa, and southeastern Wisconsin. New England was also hard hit by industrial decline during the same era. Industry has been decl... |
why home deliveries are so common in the us | > Big things that are shipped on a pallet, like a TV, are delivered to a bigger shipping terminal.
Do you take the bus to pick it up, then?
> While for the US we constantly see package thief videos in /r/videos, with them just being dropped off in front of the door with no expected supervision or signature.
We c... | [
"Today, mail is delivered once a day on-site to most private homes and businesses. The USPS still distinguishes between city delivery (where carriers generally walk and deliver to mailboxes hung on exterior walls or porches, or to commercial reception areas) and rural delivery (where carriers generally drive). With... |
How did allied soldiers get there supplies during the offensive against Germany? | Do you mean after D-Day ?
Immediately after D-Day the allies built two Mulberry Harbours, here is a picture : _URL_0_
The reason that they were needed is that the Allies had realised after the failure at Dieppe in 1942 that taking an already built harbour was too difficult. So, the invasion was based on beaches. This... | [
"A memorandum to the British War Cabinet on 1 January 1917 stated that very few supplies were reaching Germany or its allies either via the North Sea or other areas such as Austria's Adriatic ports (which had been subject to a French blockade since 1914).\n",
"The Australian Red Cross reported dispatching a total... |
What is the most likley future of space travel? | Well the first step is the figure out when space travel will be worth it. In a mostly economic sense, at what point does dumping a very large amount of resources to supply a mission that won't return for at least a generation that has speculative benefits at best make sense? Well either we have developed more efficient... | [
"Features of the postulated future include an Earth governed by a World Federation in which Brazil has become the paramount great power, with Terran space travel monopolized by a Brazilian-dominated agency called the \"Viagens Interplanetarias\" (\"Interplanetary Tours\" in Portuguese). Interstellar travel is limit... |
does your body keep taking in water when you get wounded underwater? | No question is stupid. People who say that a question is stupid are the stupid ones themselves.
Anyway, no, water wouldn't fill into your body. Your heart is constantly pumping blood throughout your body, meaning that it's generating pressure to move all of your blood around (this is referred to as one's blood pressur... | [
"Urgently lifting an injured or incapacitated casualty from the water is a significant problem especially where there are few rescuers, the sea is rough, the boat has high sides or the rescuers on the shore cannot get in or close to the water to help.\n",
"If the diver is still underwater when the laryngospasm re... |
Why weren't 6.5mm cartridges more popular after WW1? | In general, nations retained the same cartridges used in ww1 up until and through ww2. Like with bolt-action rifles rather than semi-automatic ones, this was mostly due to cost during the interwar years, and then the need to maintain production of arms and ammunition during the war.
Several countries realised the limi... | [
"World War II spoiled the commercial introduction and spread of the 6.5×68mm. The cartridge became popular after World War II due to its high performance and flat trajectory, when German hunters were allowed again to own and hunt with full bore rifles. The 6.5×68mm's performance also made it that hunters who had pr... |
why buy an expensive computer monitor if a hdtv of the same size is cheaper and has the same resolution? | Monitors have better response times, more accurate colours and some even have features like USB hubs.
TV's don't have fast response times and therefore have a lot of input lag, which is fine for movies and such, but for applications and games, monitors are better. TV's process the image to try and make it look as goo... | [
"In 2011 Bennie Budler, product manager of IT products at Samsung South Africa, confirmed that monitors capable of 1920×1200 resolutions aren't being manufactured anymore. \"It is all about reducing manufacturing costs. The new 16:9 aspect ratio panels are more cost-effective to manufacture locally than the previou... |
why is it that when i'm laying down i pitch black darkness it randomly feels as if i'm falling or the bed is tipping. | I think I just saw this exact thing explained on reddit earlier. Basically, as you fall asleep, your body fully relaxes. Because your mind is still partially conscious, it tries to justify the sensation to itself. It recreates the closest feeling it's experienced. This often manifests itself as a freefall or spinning m... | [
"\"“I was in bed and about to fall asleep when I had the distinct impression that “I” was at the ceiling level looking down at my body in the bed. I was very startled and frightened; immediately [afterward] I felt that, I was consciously back in the bed again.”\"\n",
"This recollection is brought to an end when h... |
how do phones and computers transfer audio to headphones? | Sound is transmitted as a voltage signal through wires. The voltage changes just like the soundwave, and this goes into tiny magnets in headphones, or speakers, or telephones. The magnets shake the speaker back and forth as the voltage changes, and this movement makes pressure waves on the air. The pressure waves we he... | [
"Headphones (or head-phones in the early days of telephony and radio) traditionally refer to a pair of small loudspeaker drivers worn on or around the head over a user's ears. They are electroacoustic transducers, which convert an electrical signal to a corresponding sound. Headphones let a single user listen to an... |
what happens to deceased pigeons in major cities so that you rearly see their corpses. | Seems like a lot of animals go somewhere secluded to die. There are tons of raccoons, possums, and stray cats and dogs in my city too, but I never see any dead ones unless they've been run over. | [
"There is ample reason for the concerns of pigeons damaging property, due to their size and proximity to people and their dwellings. Pigeons often cause significant pollution with their droppings, though there is little evidence of them driving out other bird species. Pigeons are labeled an invasive species in Nort... |
Can we apply the laws of physics universally no matter which direction or reference of time we are observing? | Not always.
For example the famous law of Conservation of Energy:
If that spacetime is standing completely still, the total energy is constant. But that is not the case, so energy is not totally conserved. Energy conservation becomes tricky when time is bent.
A good example is Redshift of photons. They are losing en... | [
"The equations used in physics to model reality do not treat time in the same way that humans commonly perceive it. The equations of classical mechanics are symmetric with respect to time, and equations of quantum mechanics are typically symmetric if both time and other quantities (such as charge and parity) are re... |
WWI letter found in cupboard in Lübeck, Northern Germany. I need your help and knowledge to figure it out. | I just skimmed through it and couldn't read everything, but here is a short summary:
Old woman (and her husband) cares for her granddaughter but can barely afford it. Her daughter, the child's mother, seems to be dead and now she searches for her son-in-law, who is at war. There seems to be a problem with the relat... | [
"His writings were found by chance in 1993 in the manuscript store of the Berlin State Library. The surviving part covers a range of 25 years between 1625 and 1649. The book was folded from 12 sheets of paper which he bought at the end of the war in 1648 to write a fair copy of his notes. The 192 pages tell of a 22... |
What happened to the land and the debris of war such as weapons and vehicles that were left after long and destructive battles like Verdun or Stalingrad? Basically, who cleaned up the mess and how did they do it? | Note that many areas which have seen prolonged fighting in modern wars *haven't* been completely cleaned up, with some still containing dangers such as live explosives.
With this in mind, I'd like to ask a follow-up question: which areas have seen prolonged fighting with significant leftover debris/ordnance that *was*... | [
"In the aftermath of a war, large areas of the region of conflict are often strewn with \"war debris\" in the form of abandoned or destroyed hardware and vehicles, mines, unexploded ordnance, bullet casings and other fragments of metal.\n",
"Large portions of the buildings were destroyed after the war. Until 1947... |
Do the planets all orbit the Sun on the same plane as Earth like all the models depict, or do the planets orbit the Sun like how we depict electrons orbiting an atom? | All planets orbit on the same plane (more or less, within a few degrees) as the Earth. Check out [this response from the FAQs for more info](_URL_0_). | [
"Most large objects in orbit around the Sun lie near the plane of Earth's orbit, known as the ecliptic. The planets are very close to the ecliptic, whereas comets and Kuiper belt objects are frequently at significantly greater angles to it. All the planets, and most other objects, orbit the Sun in the same directio... |
how che guevara being a marxist and everything that capitalist america can’t stand for ended up being such a pop culture icon in america? | I am not American, and dont really know but i would say that he was originally adopted by counter-culture because he **was** everything that Capitalist America didnt stand for. Counter-culture then became 'the cool' thing and it sort of just took off from there.
[Here's](_URL_0_) a little overview done by the BBC on h... | [
"Amongst the youth of Latin America, Guevara's memoir \"The Motorcycle Diaries\" has become a cult favorite with college students and young intellectuals. This has allowed Guevara to emerge as \"a romantic and tragic young adventurer, who has as much in common with Jack Kerouac or James Dean as with Fidel Castro.\"... |
How did WWII Navy pilots find the aircraft carrier after a mission? | More input is always welcome; while we wait, you may be interested in [this thread asking the same question](_URL_0_). u/thefourthmaninaboat provides the general overview, while u/DBHT14 provides a specific view at the USN, specifically at Midway. [There's also this prior thread](_URL_1_) with a tick more discussion, a... | [
"An extensive search for the aircraft was organised, which included the Royal Navy ships HMS \"Barhill\" and HMS \"Gambia\" as well as the Maltese civilian salvage vessel \"Sea Salvor\". The search effort involved the pioneering use of underwater TV cameras, developed by a team at the UK Admiralty Research Laborato... |
why is it so difficult to make reflections in video games? | Doing a reflection essentially means drawing the scene twice, once from the camera's point of view and once from "within" the mirror.
Drawing the scene takes a lot of processing power. If the game runs at say 60 fps normally, having to draw the scene twice will make that framerate drop significantly.
That said it sho... | [
"The team wanted to avoid punishing the player for applying everyday logic in \"Maniac Mansion\". Fox noted that one Sierra game features a scene in which the player, without prior warning, may encounter a [[game over]] screen simply by picking up a shard of glass. He characterized such game design as \"sadistic\",... |
About to begin studying History at University. Anything I should know? | Be prepared to change your major simply because the university experience is all about discovery - including what really sets you on fire. It may be history, but it may be something else. Be agile and flexible. If history is the focus of your passion after the dust settles, that's a great place to put one foot, but sin... | [
"The history of the University is usually traced to 1841. It was in that year that five young men who were employed by local industrialist Frederic Schwann, who had been born in Frankfurt, approached their employer for support in establishing a new subscription library and some elementary educational classes, ‘to s... |
What (specifics) do we know about clothing of Northern/Central European men during the late Bronze- / early Iron-age? | (Don't worry about the flair, I removed it - the filter picked up on "sport".)
I'm not entirely sure of what you mean about a culture generally clad in furs and skins, because textile use was most common by 600 BCE, so I'm going to just look at clothing in general from around this time. The best preserved Bronze Age c... | [
"The Iron Age is broadly identified as stretching from the end of the Bronze Age around 1200 BC to 500 AD and the beginning of the Medieval period. Bodies and clothing have been found from this period, preserved by the anaerobic and acidic conditions of peat bogs in northwestern Europe. A Danish recreation of cloth... |
How true is the statement that England abandoned Australia after the Fall of Singapore in WW2? | The British released three divisions of volunteer Australians from the Western Desert to go back to Australia in the spring of 1942. These troops, the 6th, 7th and 9th infantry divisions played a key role in driving the Japanese army out of Papua New Guinea in 1942 and e... | [
"The another major issue brought up around this time was national defence. Following independence, the British were still defending Singapore, but had announced they would be withdrawing by 1971, due to pressures at home and military commitments elsewhere in the world. This caused considerable alarm locally, partic... |
Quick history of astronauts countering Van Allen radiation belts? | I don't have time for a full history, but broadly speaking we've known that space was radioactive since the very early days of the Space Race. Explorer 1 was the first satellite to carry a geiger counter, which went crazy when it entered the radiation belts. This led one of the members of the science team, Ernie Ray, t... | [
"In addition to the charged particles of the Van Allen Belts, the spacecraft were also designed to measure cosmic rays, galactic radio emissions, magnetic fields, radio propagation, and micrometeoroid flux. They were also meant to study artificial radiation belts created by high altitude nuclear tests, but the rati... |
how isaac newton was able to test and prove that an object in motion will stay in motion unless acted upon by another force, when you can never truly have something without other forces acting on it to prove his theory | Isaac Newton did not perform experiments and describe the results. He did make observations, drawing on the work of other authors as well, and then used *reasoning* to formulate general rules according to which he supposed the world worked. An emphasis on reasoning rather than experimentation is one reason that science... | [
"While Newton was able to formulate his law of gravity in his monumental work, he was deeply uncomfortable with the notion of \"action at a distance\" that his equations implied. In 1692, in his third letter to Bentley, he wrote: \"\"That one body may act upon another at a distance through a vacuum without the medi... |
why didn't the usa drop nuclear bombs on tokyo but dropped them where they did? | You can read the deliberations that the US scientists and military men had in May 1945 over the first nuclear targets [here](_URL_0_). The possibility of bombing the Emperor's palace was discussed but dismissed — they didn't want to kill the Emperor and the high command, they wanted to induce them to surrender. They fe... | [
"On 30 June 2007, Japan's defense minister Fumio Kyūma said the dropping of atomic bombs on Japan by the United States during World War II was an inevitable way to end the war. Kyūma said: \"I now have come to accept in my mind that in order to end the war, it could not be helped (shikata ga nai) that an atomic bom... |
Why is brain death final? Like, why can't we restart or reboot a brain that's been dead for only a few hours? | Yes, it is decay (aka mass cellular death).
Neurons have *huge* metabolic needs. If you cut off their oxygen supply, neurons lose their ability to maintain their ionic gradients fairly quickly. This results in depolarization, excitotoxicity, and eventual cellular death. Once they're dead, they're dead, no bringin... | [
"Brain death may result in legal death, but still with the heart beating and with mechanical ventilation, keeping all other vital organs alive and functional for a certain period of time. Given long enough, patients who do not fully die in the complete biological sense, but who are declared brain dead, will usually... |
Why don't we just point Hubble at Pluto instead of waiting a decade for a satellite to take pictures of it? | We did. You can find some two sample images [here](_URL_0_), but you should direct your view to the top left of each half, which show the actual Hubble images. Each pixel is over 100 miles across, so we don't really see much. Pluto is just really far away, and our telescopes don't really have the resolving power, and e... | [
"On February 12, 2015, NASA released new images of Pluto (taken from January 25 to 31) from the approaching probe. \"New Horizons\" was more than away from Pluto when it began taking the photos, which showed Pluto and its largest moon, Charon. The exposure time was too short to see Pluto's smaller, much fainter, mo... |
A question about Human cell regeneration. | **Neurogenesis**, which is the generation of new neurons, only occurs in certain parts of the adult brain. Many of the neurons you are born with are, in fact, the ones you're stuck with until they or you die. However, even "permanent", non-replicating cells need to be replenished; over the course of 5 or so years, ever... | [
"One of the most promising sources of heart regeneration is the use of stem cells. It was demonstrated in mice that there is a resident population of stem cells or cardiac progenitors in the adult heart – this population of stem cells was shown to be reprogrammed to differentiate into cardiomyocytes that replaced t... |
how do integrated circuits/electronics work | There are a handful of basic building blocks for any circuit: resistors, capacitors, inductors, and transistors.
An integrated circuit as you'd have seen it in the 1970s would consist of 10 to 30 transistors, and less than 5 each resistors and capacitors.
Today due to advances in technology, the number of transistor... | [
"An integrated circuit is a miniaturized electronic circuit that has been manufactured in the surface of a thin substrate of semiconductor material. Integrated circuits are used in almost all electronic equipment in use today and have revolutionized the world of electronics. The integration of large numbers of tiny... |
what is the line between the first amendment and hate crimes? | Ahoy, matey! Yer not alone in askin', and kind strangers have explained:
1. [ELI5: The line between freedom of speech and breaking the law. Eg racism ](_URL_4_) ^(_13 comments_)
1. [ELI5 how can we prosecute hate speech if the First Amendment says we can't abridge the freedom of speech. ](_URL_1_) ^(_15 comments_)
1. ... | [
"The Matthew Shepard Act expanded the federal hate crime laws to include gender, gender identity, and sexual orientation. In order to qualify as a federal hate crime in the United States, the crime must include successful or attempted bodily injury due to the use of firearm, explosives, weapons, fire, or incendiary... |
why is hemp so much better than trees for making stuff? | The real value in using Hemp over traditional forest wood for cellulose based products is the way the two are cultivated. Even a small grove of trees takes years for the wood to mature and be usable, where as Hemp has a standard growth rate of only a few weeks. It is also a very good replacement for other production so... | [
"Hemp is considered by a 1998 study in \"Environmental Economics\" to be environmentally friendly due to a decrease of land use and other environmental impacts, indicating a possible decrease of ecological footprint in a US context compared to typical benchmarks. A 2010 study, however, that compared the production ... |
Why do I see RGB when I look away from a projector light? | This is because the DLP projector is rapidly alternating between projection of the red, green, and blue component images. This is called the 'rainbow effect.'
[Wikipedia has an entry on it](_URL_0_) | [
"RGB (Red, Green, Blue) describes what kind of \"light\" needs to be \"emitted\" to produce a given color. Light is added together to create form from darkness. RGB stores individual values for red, green and blue. RGB is not a color space, it is a color model. There are many different RGB color spaces derived from... |
How much of a presence did the Inca Empire have in the rainforests east of the Andes? What did they call the natives of the Amazon region? | Actually, not as much as you might expect. [Tawantinsuyu](_URL_0_) reached across the whole of western South America, yet its most glaring geographical boundary is not the Pacific, but the Amazon Basin. Groups in the Amazon were known to an extent by Andeans and coastal dwellers, but it is a dialogue archaeologists are... | [
"In 2017, the 5,972,606 indigenous people formed about 25.7% of the total population of Peru. At the time of the Spanish invasion, the indigenous peoples of the rain forest of the Amazon basin to the east of the Andes were mostly semi-nomadic tribes; they subsisted on hunting, fishing, gathering and migrant agricul... |
What plants have gone extinct along with animals over the years? | Well, I'm not a scientist, but Wikipedia's [entry](_URL_1_) on paleobotany seems fairly thorough, and it links to a list of [extinct plants](_URL_0_). | [
"The plant was long thought to be extinct but a small population was discovered in 1998 by Stedson Stroud. As of 2011, it was considered \"effectively extinct in the wild\" by experts at Kew Botanical Garden because there were no longer any flowering plants left in the wild. Only one adult plant was left by 2010, a... |
How powerful can placebo's be and could they be a legitimate replacement for expensive and complicated medication? | 30% of the time they work, so if you have a really expensive medicine that works 35% of the time, placebo can be an alternate. | [
"A systematic review concluded that \"tricyclic antidepressants and traditional anticonvulsants are better for short term pain relief than newer generation anticonvulsants.\" A further analysis of previous studies showed that the agents carbamazepine, venlafaxine, duloxetine, and amitriptyline were more effective t... |
How old might the oldest conceivable DNA sample on Earth be? | Digging a little deeper I found this study where [DNA was amplified and sequenced from a 120-135-million-year-old weevil](_URL_0_) which is cool and all, but the answer I'm really looking for would come from a biophysics study I think. I'm finding it hard to belive that nobody has done an experiment where they have st... | [
"In 2013, a German team reconstructed the mitochondrial genome of an \"Ursus deningeri\" more than 300,000 years old, proving that authentic ancient DNA can be preserved for hundreds of thousand years outside of permafrost.\n",
"In 2013, a German team reconstructed the mitochondrial genome of an \"Ursus deningeri... |
_URL_0_ can draw my family tree back to e.g. Charlemagne, Constantine the Great and Philip II of Macedon. Is this actually a reliable tool? | I don’t know that this is strictly a history question. You may want to ask it over at r/genealogy. However, as an avid genealogist I can tell you that you are absolutely right to be skeptical.
Statistically, every person of Western European descent is a descendant of Charlemagne. In genealogy what matters is whether o... | [
"The tree is largely based on the late 9th-century \"Anglo-Saxon Chronicle\", the West Saxon Genealogical Regnal List (reproduced in several forms, including as a preface to the [B] manuscript of the Chronicle), and Asser's \"Life of King Alfred\". These sources are all closely related and were compiled at a simila... |
why aren't car insurance companies legally restrained from only offering exorbitant rates? | There is no clear factual answer to this question, but the bottom line is that various state legislatures have declined to impose such requirements. This could be because of corporate influence, it could be because of a belief that free market competition will guarantee good service. Regardless of the reason, legislato... | [
"Most insurers around the world have introduced some form of merit-rating in automobile third party liability insurance. Such systems penalize at-fault accidents by premium surcharges and reward claim-free years by discounts, commonly known as a \"no-claims discount\".\n",
"High risk drivers are often undesirable... |
why do artificially made things cost less than natural things? | It comes down to economies of scale. It’s cheaper to make a thousand gallons of apple- scented sugar water than it is to find enough good apples, transport them to a juicing facility, process them into juice, transport the juice to the point of sale, and also have to clean up the juicer machinery and deal with the det... | [
"However, artificiality does not necessarily have a negative connotation, as it may also reflect the ability of humans to replicate forms or functions arising in nature, as with an artificial heart or artificial intelligence. Political scientist and artificial intelligence expert Herbert A. Simon observes that \"so... |
What would cause a pint glass to spontaneously combust? | That didn't spontaneously combust, it just shattered. Glass does that when it is heated or cooled unevenly. If you wanted to, you could repeat it by gently heating another pint glass to the boiling temprature of water, then dipping one end of it in ice water. The cold end shrinks, creating internal stress, because t... | [
"The irregular glass wafers, called \"fractures\", are prepared from very hot, colored molten glass, gathered at the end of a blowpipe. A large bubble is forcefully blown until the walls of the bubble rapidly stretch, cool and harden. The resulting glass bubble has paper-thin walls and is immediately shattered into... |
if the earth "wobbles" as it spins and orbits the sun, what prevents it from spinning out of control? | INTERESTINGLY, Hyperion, due its unusual shape and geology; its resonance with Titan; and dynamical flattening effects from many objects in the Saturn system, DOES spin out of control. Wooooooo | [
"In graphical terms, the Earth behaves like a spinning top, and tops tend to wobble as they spin. The spin of the Earth is its daily (diurnal) rotation. The spinning Earth slowly wobbles over a period slightly less than 26,000 years. From our perspective on Earth, the stars are ever so slightly 'moving' from west t... |
Why was flanking a larger force (such as during the Battle of Cannae) so effective? Wouldn't the smaller force be worn out by the larger one even if they did encircle them? | In ancient battles, on the whole, the heavy infantry of the main battle line was very much focused on the fight in front of them. The anticipation of having to engage in close combat was mortifying, and the business at hand required their complete attention. In addition, given the minimal technological means of conveyi... | [
"As the two phalanxes closed for battle, both shifted to the right. (This was a common occurrence in hoplite battles—hoplites carried their shield on their left arm, so men would shift to the right to gain the protection of their neighbor's shield as well as their own.) This shift meant that, by the time the armies... |
How can one locate the records of a deceased Red Army soldier in WWII? | There's online database "Memorial" of all USSR citizens, who served in Soviet Army and who were killed or missed in action during WWII.
It is in russian and you would need to enter your grandpa names in russian in order to search.
Several caveats:
* some russian and ukranian frequent first/last name combination m... | [
"In the post-war era the military search service Deutsche Dienststelle (WASt) has been responsible for providing information for the families of those military personnel who were killed or went missing in the war. They maintain the files of over 18 million men who served in the war. By the end of 1954, they had ide... |
How much do we actually know about the seafloor | We have very detailed [bathymetric](_URL_3_) maps of a lot of the ocean (e.g. _URL_0_). But that's only like having a topographic map of land - it doesn't tell you what's on it, but is fairly easy to do via remote sensing (e.g. sonar, etc).
We have actually explored the sea floor fairly well. Remote submersibles can b... | [
"These data suggest human occupation when the sea level was lower than present, and that submerged archaeological sites could occur along the paleocoastline beyond the current shorelines of Haida Gwaii (Fedje & Christensen, 1999) and Southeast Alaska.\n",
"Apart from sediments the expedition looked at biology. Th... |
what is a delegate (presidential race)? | You are correct delegates are points, but they are people. In June / July all the delegates will assemble at the party conventions and formally cast their votes for presidential nominee. The primaries and caucuses say how many of a states delegates will vote for you on first ballot. Win 50% + 1 delegate votes and you... | [
"In the modern U.S. presidential election process, voters participating in the presidential primaries are actually helping to select many of the delegates to these conventions, who then in turn are pledged to help a specific presidential candidate get nominated. Other delegates to these conventions include politica... |
why aren't there massive lakes of water floating around in space? | There are, but they are giant balls of ice | [
"Because of its high salt concentration, the lake water is unusually dense, and most people can float more easily than in other bodies of water, particularly in Gunnison Bay, the saltier north arm of the lake.\n",
"BULLET::::2. The Water Water is described as being exterior to the sphere of the Earth and interior... |
let’s say i wake up before my alarm 10 minutes early, and i decide to sneak in extra sleep. i either go back to sleep which feels like an hour when in reality only 5 minutes has passed or i sleep which feels like 5 mins when actually an hour has passed. why does this occur? | There are different stages of sleep: stage 1, 2, 3, 4, and REM. If you wake up during REM (the dreaming stage basically), your body releases a chemical that prevents you from moving, and it might not have been fully removed yet.
If you don’t fully wake up i.e. hit snooze and immediately close your eyes again, you can ... | [
"A common false awakening is a \"late for work\" scenario. A person may \"wake up\" in a typical room, with most things looking normal, and realize he or she overslept and missed the start time at work or school. Clocks, if found in the dream, will show time indicating that fact. The resulting panic is often strong... |
what is an arduino micro controller? ive seen a lot of posts about people doing awesome stuff with them. but i haven't been able to get a straight answer for just what it actually is | It's basically a circuit board and small CPU. I don't /think/ it has a proper operating system, but it does have a programming language attached. Connect some other electronic parts to it and come up with the program, and you have an arbitrary electronics device.
IE; attach it, a microphone, a small motor, and some ... | [
"The micro-controller simulation in Proteus works by applying either a hex file or a debug file to the microcontroller part on the schematic. It is then co-simulated along with any analog and digital electronics connected to it. This enables its use in a broad spectrum of project prototyping in areas such as motor ... |
Who first thought of stairs? | hi! if you don't get answers here, this question might be worth x-posting to an archaeology sub, or /r/AskAnthropology | [
"It is believed the stairs were built some time before the rule of Tiberius (14–37), as they were not mentioned by name in any ancient texts that predate this period. Their first use as a place of execution is primarily associated with the paranoid excesses of Tiberius' later reign.\n",
"The staircase design had ... |
Why do we see meteor showers some specific days only? | There are various asteroid "clouds" in our neighbourhood, but their orbit around the sun only intersects with our orbit around the sun every now and then. When the orbit of an asteroid cloud intersects that of the Earth, we can see a meteor shower. On other days, there are simply little to no meteors of sufficient size... | [
"The shower is visible from mid-July each year, with the peak in activity between 9 and 14 August, depending on the particular location of the stream. During the peak, the rate of meteors reaches 60 or more per hour. They can be seen all across the sky; however, because of the shower's radiant in the constellation ... |
assassins creed story arc with the apple and pieces of eden. | A guy over on /r/assassinscreed recently posted a couple of excellent synopses for all of the games. Warning: they do contain NSFW language - or language not suitable for 5 year olds!
[Assassin's Creed 1](_URL_0_)
[Assassin's Creed 2](_URL_2_)
[Assassin's Creed: Brotherhood](_URL_1_)
[Assassin's Creed: Revelations]... | [
"To drive the story, the team had to come up with some goal that both the Assassins and Templars were searching for. Philippe Morin had suggested using the apple of Eden, which the team initially thought to be a humorous aspect for everyone fighting over an apple. However, as they researched into the game more, the... |
What does stingray venom do? | > Stingrays have a spine at the base of their tail that contains a venom gland. The spine, including the venom gland, may be broken off in the attack and may remain in the wound. The venom has vasoconstrictive properties that can lead to cyanosis and necrosis, with poor wound healing and infection. Symptoms include im... | [
"The venom of the stingray has been relatively unstudied due to the mixture of venomous tissue secretions cells and mucous membrane cell products that occurs upon secretion from the spinal blade. Stingrays can have anywhere between one and three blades. The spine is covered with the epidermal skin layer. During sec... |
Why is it that some nations within the Soviet Union (Ukraine, Georgia, etc.) received the status of SSR while others (Karelia, Chechen, etc.) were only ASSRs? | It was a perilous issue in the early years of the USSR, and mainly had to do with population and territorial size as well as loyalty to the regime (though in the case of the Baltics, Stalin made each an SSR to characterize themselves as liberators to the rest of the world). Making Chechnya a full-fledged Republic would... | [
"All of the former Republics of the Union are now independent countries, with ten of them (all except the Baltic states, Georgia and Ukraine) being very loosely organized under the heading of the Commonwealth of Independent States. However, most of the international community did not consider the Baltic countries (... |
what is the difference between shaving using a trimming machine , a razor or waxing besides the physical method and why is one preferred over the other | A trimmer leaves the hair partially there and is merely cutting it down to a certain length. You use this when you want to keep your beard but groom it, and trimmers are often used when doing normal haircuts for the areas that are going to be relatively short.
A razor cuts much closer, shaving off almost all of the ex... | [
"The shaving process is a finishing operation where a small amount of metal is sheared away from an already blanked part. Its main purpose is to obtain better dimensional accuracy, but secondary purposes include squaring the edge and smoothing the edge. Blanked parts can be shaved to an accuracy of up to 0.025 mm (... |
Did the Kingdom of Saxony intend to conquer some or all of Austrian Silesia prior to the annexation of the latter by the Kingdom of Prussia? | There wasn't a kingdom of Saxony before the annexation of Silesia by the Kingdom of Prussia. | [
"In 1813 the Kingdom of Prussia occupied large amounts of Saxony's territory in the Battle of Leipzig, including the Electoral Circle (which had been renamed the \"Wittenberg Circle\" in 1807); in May 1815 a treaty was signed in which Saxony ceded this territory to Prussia. In June 1815 they all became part of the ... |
advances in (metal) armor thourgh the centuries | This is an important question in the history of armour. In fact, this is a huge question, and there's a lot to say about it.
I will start off with some historiography. The early historiography of armour is saw medieval armour's development as being like that of early 20th century battleships, or 20th century tanks - m... | [
"Armour has been used throughout recorded history. It has been made from a variety of materials, beginning with the use of leathers or fabrics as protection and evolving through mail and metal plate into today's modern composites. For much of military history the manufacture of metal personal armour has dominated t... |
How do we simultaneously know how far away a stellar object is *and* its chemical makeup? | each element has a unique set of spectral lines it leaves. We look at all the spectral lines of the star and are able to determine its makeup. Redshifting merely shifts all of these values uniformly toward the red end of the spectrum. But the spacing between the lines remains the same.
edit: analogy. Imagine I have a... | [
"In addition to being far away, many stars of such extreme mass are surrounded by clouds of outflowing gas created by powerful stellar winds; the surrounding gas interferes with the already difficult-to-obtain measurements of stellar temperatures and brightnesses and greatly complicates the issue of estimating inte... |
Does the body prevent inhalation of the lungs when a person is knocked out and under water? | In lifesaving you learn that the body keeps breathing and so an unconscious submerged person will drown choking on water - though I'm not sure they keep inhaling after the that initial gulp of water.
An interesting aside, the difference between a Personal Flotation Device or PFD (vest type) and a true Lifejacket is t... | [
"If the breathing gas in a diver's lungs cannot freely escape during an ascent, the lungs may be expanded beyond their compliance, and the lung tissues may rupture, causing pulmonary barotrauma (PBT). The gas may then enter the arterial circulation producing arterial gas embolism (AGE), with effects similar to seve... |
If Black Holes have supposedly infinite density and gravity has infinite range why is the entire universe not pulled into it? | Infinite density does not mean infinite mass, so as your mass is still some finite value, it behaves similarly to a gravitational point source.
For example, if the Sun turned into a blackhole right now, I would only notice 8 minutes later when it suddenly looked like someone decided to turn off daylight, otherwise we... | [
"Gravitational collapse requires great density. In the current epoch of the universe these high densities are only found in stars, but in the early universe shortly after the Big Bang densities were much greater, possibly allowing for the creation of black holes. High density alone is not enough to allow black hole... |
How can a body accept an organ from a different person if they have different DNA? | Immune recognition of self vs non-self is a pretty complicated thing. Different organs and different protocols require different degrees of matching. For solid organs, you can get by with matching by the major blood ground antigen. For bone marrow, you need more.
Invariably, left untreated (barring autotransplantation... | [
"Organ transplantation is a medical procedure in which an organ is removed from one body and placed in the body of a recipient, to replace a damaged or missing organ. The donor and recipient may be at the same location, or organs may be transported from a donor site to another location. Organs and/or tissues that a... |
why is eating too much after a long period of starvation dangerous? | This is an extremely difficult to answer question in a manner for a 5 year old to understand because it requires a basic biochemistry background to understand but here it goes:
In starvation mode your body is conserving energy. It takes a little energy to digest food and get things going. To make this energy your nee... | [
"Victims of starvation are often too weak to sense thirst, and therefore become dehydrated. All movements become painful due to muscle atrophy and dry, cracked skin that is caused by severe dehydration. With a weakened body, diseases are commonplace. Fungi, for example, often grow under the esophagus, making swallo... |
why do audience members at a sitcom filming laugh at everything? | A) If you're at the taping of a show, chances are you're already a fan of it, which means you'll be more likely to laugh. The excitement of actually being there probably plays into this as well. I know I'd be pretty giddy if I got to go to a Seinfeld taping or some such.
B) People are much more likely to laugh when i... | [
"Audience reactions were live, thus creating a far more authentic laugh than the canned laughter used on most filmed sitcoms of the time. Regular audience members were sometimes heard from episode to episode, and Arnaz's distinctive laugh could be heard in the background during scenes in which he did not perform, a... |
Were swords/bows/etc.. controlled from general masses in any given periods? | FYI, you'll find a few examples in the FAQ to get you started
* [Gun (and other weapons) control](_URL_0_) | [
"In the 19th century, simple cross-hilt small swords were also produced, largely as ceremonial weapons that were evocative of more ancient types of weapons. An example is the Model 1840 Army Noncommissioned Officers' Sword, which is still used by the United States Army on ceremonial occasions. As the wearing of swo... |
Would someone be able to make a flashlight like device that used light out of the visible spectrum? | Were you describing an [active infrared night vision system](_URL_0_)? | [
"A variety of light sources can be used, ranging from simple flashlights to dedicated devices like the Hosemaster, which uses a fiber optic light pen. Other sources of light including candles, matches, fireworks, lighter flints, steel wool, glowsticks, and poi are also popular.\n",
"An electric eye is a photodete... |
Is it possible for junk foods to make your body gain more weight than the actual weight of the food itself? If so, how does this happen? | So you're getting two different sets of answers based on two different readings of your questions.
First, conservation of mass is a thing. Re-arranging molecules won't let you get a higher mass. Even fixing gasses probably won't get you there, because you are expending energy in the process of re-arrangement.
Secon... | [
"When junk food is consumed very often, the excess fat, simple carbohydrates, and processed sugar found in junk food contributes to an increased risk of obesity, cardiovascular disease, and many other chronic health conditions. A case study on consumption of fast foods in Ghana suggested a direct correlation betwee... |
how come that when you go to bed at 11pm you have a hard time to leave your bed at 7am, but when you go to bed at 3am you dont have any problems waking up at 11am while you had the same hours of sleep? | Might be a number of things.
1) You aren't used to waking up early, so your body isn't ready for it. If you don't usually wake up at 7am and then suddenly do, it'll be hard.
2) It's often colder in the morning, especially in the winter. Getting out of bed in the cold is hard.
3) It's much brighter at 11am than 7a... | [
"Affected people often report that while they do not get to sleep until the early morning, they do fall asleep around the same time every day. Unless they have another sleep disorder such as sleep apnea in addition to DSPD, patients can sleep well and have a normal need for sleep. However, they find it very difficu... |
What’s in the direct center of a black hole? When light and other various things get sucked into the black hole what happens to them? Are they crushed? What happens when something goes into a black hole? | Any particle that crosses the event horizon must move toward the singularity. We cannot predict what happens to the particle beyond that; our current theory does not have that capability. (Indeed, this is what it means for there to be a singularity.) | [
"The defining feature of a black hole is the appearance of an event horizon—a boundary in spacetime through which matter and light can only pass inward towards the mass of the black hole. Nothing, not even light, can escape from inside the event horizon. The event horizon is referred to as such because if an event ... |
why do different languages each have their own version of the same names? | Names begin as a single name in a parent language like Latin and will be spread throughout the geographical area where that language is spoken (in the case of Latin, most of Western Europe.) However, languages change gradually over time, with speakers slowly but surely changing the pronunciation rules of individual let... | [
"Number names are rendered in the language of the country, but are similar everywhere due to shared etymology. Some languages, particularly in East Asia and South Asia, have large number naming systems that are different from both the long and short scales, for example the Indian numbering system.\n",
"Dual namin... |
How many individual bacteria/viruses does it take to infect you with a disease? | Each virus and bacterium has a different design, so some are more infectious than others. For example, the number of vibrio cholerae (which causes cholera) that you need to ingest to become infected is between 1,000 and 100,000,000, but the number of EHEC (a really wicked E. coli strain) that you need is closer to 10. ... | [
"Typically, the infection enters the body through a break in the skin such as a cut or burn. Risk factors include poor immune function such as from diabetes or cancer, obesity, alcoholism, intravenous drug use, and peripheral artery disease. It is not typically spread between people. The disease is classified into ... |
How long would it have taken for a civilian to travel from New York City to Madrid circa 1914? | From the 1870s to 1900 the White Star Line had a policy of seeing how fast they could do their Liverpool-New York line. The last record holder was the steam ship SS Teutonic in 1890, who reached New York harbour in 5 days, 16 hours and 31 minutes. In the 1900s White Star changed their policy to comfort over speed, so i... | [
"BULLET::::- 1939 24 May, owner Francisco Sarabia set a new record for a non-stop flight from Mexico City to New York City in 10 hours and 47 minutes. He also set records for flights between Los Angeles to Mexico City, Mexico to Chetumal, Mexico to Mérida and Mexico to Guatemala.\n",
"In 1939, a passenger traveli... |
Is sulphuric acid is stronger than hydrofluoric, why can HF acid dissolve glass? | The "strength" of an acid can be a bit of a misnomer, depending on what you are talking about.
"Strong," when discussing acids, is a measure of how completely that acid will be ionized in aqueous solution. In other words, a strong acid, like sulfuric acid (H*_2_*SO*_4_*) will "completely" dissociate in water:
H*_2_*... | [
"Hydrofluoric acid and its anhydrous form, hydrogen fluoride, is also used in the production of fluorocarbons. Hydrofluoric acid has a variety of specialized applications, including its ability to dissolve glass.\n",
"Hydrofluoric acid is a solution of hydrogen fluoride (HF) in water. It is a precursor to almost ... |
How much of the universe's matter is in interstellar gases? | You mean ordinary matter? Because we still have no proper theory of quantifying dark matter. Excluding dark matter and energy, only one-tenth of ordinary matter is believed to be found in stars..so that means 9/10th of ordinary matter is dispersed in the interstellar medium.
EDIT: What I gave you above was a rough es... | [
"Interstellar matter, considered dense in an astronomical context, is at high vacuum by laboratory standards. Physicists showed in the 1920s that in gas at extremely low density, electrons can populate excited metastable energy levels in atoms and ions, which at higher densities are rapidly de-excited by collisions... |
If a humming bird is flying inside an airplane is the airplane heavier by the weight of the humming bird? | Yes. On a technical level, The hummingbird flies by accelerating air downwards, to produce an upwards force. This momentum will, even if it dissipates through all the air in the cabin, create a *slightly* higher pressure on the bottom of the cabin than the top. The difference on pressure, integrated over the inside ... | [
"Hummingbirds have many skeletal and flight muscle adaptations which allow great agility in flight. Muscles make up 25–30% of their body weight, and they have long, blade-like wings that, unlike the wings of other birds, connect to the body only from the shoulder joint. This adaptation allows the wing to rotate alm... |
The primary cause of global warming is greenhouse gasses--but what about all of our waste heat? | Waste heat does have a local effect, but it is believed to account for only about 1% of anthropogenic forcing globally. Global forcing from waste heat was 0.028 W/m2 in 2005, while total anthropogenic forcing was about 2.9 W/m2 and net anthropogenic forcing was around 1.6 W/m2.
_URL_1_
_URL_0_ | [
"\"Global warming has been a great concern of many environmental scientists. Scientists believe that the greenhouse effect is responsible for global warming. Greatly increased amounts of heat-trapping gases have been generated since the Industrial Revolution. These gases, such as CO, CFC, and methane, accumulate in... |
how do sports leagues coordinate scheduling so many games without running into any conflicts? | a professor of mine in graduate school (he was an Operations Research guy), scheduled MLB games. Long story short, he ran a huge optimization program with constraints given to him by the league and the teams (i.e., need to be home these dates..no more than X consecutive games on the road, etc.). | [
"The schedule can also be used for \"asynchronous\" round-robin tournaments where all games take place at different times (for example, because there is only one venue). The games are played from left to right in each round, and from the first round to the last. When the number of competitors is even, this schedule... |
Did the culture of Carthage differ significantly from the culture of the older Phoenician city-states in the Levant? | According to Richard Miles' *Carthage Must Be Destroyed*, *Qart Hadasht*, or "New City" was mainly ~~Tyrrhenian~~ Tyrian in origin; this follows both the foundation myth of the city and the preeminence of Melqart and Estarte, the chief city gods of Tyre, in Carthage. Tyre was conquered by Hammurabi of Babylon in 572 B... | [
"Carthage was one of a number of Phoenician settlements in the western Mediterranean that were created to facilitate trade from the cities of Sidon, Tyre and others from Phoenicia, which was situated in the coast of what is now Lebanon. In the 10th century BC, the eastern Mediterranean shore was inhabited by variou... |
why do symptoms of the common cold change as your body gets over them? | Basically the beginning is the foreign bodies attacking your cells and vice versa, damaging the near by tissue (pain). The ending is the left over waste products remaining inside your body from the fight and your body finding methods to move them from essential functioning areas or just expelling them. | [
"The common cold, also known simply as a cold, is a viral infectious disease of the upper respiratory tract that primarily affects the nose. The throat, sinuses, and larynx may also be affected. Signs and symptoms may appear less than two days after exposure to the virus. These may include coughing, sore throat, ru... |
why are "pretty" plants and flowers much less resistant than weeds and ugly small wild flowers? | Pretty garden plants are often a long way from home, so they're exposed to a variety of pests and diseases they wouldn't have much resistance to.
Weeds are generally local, or of they're incomers they're successful ones which have already shown they can cope with the local ecosystem.
The other thing is that garden pl... | [
"Some of the species, notably \"Calystegia sepium\" and \"C. silvatica\", are problematic weeds, which can swamp other more valuable plants by climbing over them, but some are also deliberately grown for their attractive flowers.\n",
"Roses (\"Rosa\" species) are susceptible to a number of pests, diseases and dis... |
I need help identifying this disorder. | There are many things that could cause stunted growth. If you have more information that might be helpful, but I'm not confident that an accurate call can be made here. | [
"This is a list of major and frequently observed neurological disorders (e.g., Alzheimer's disease), symptoms (e.g., back pain), signs (e.g., aphasia) and syndromes (e.g., Aicardi syndrome). There is disagreement over the definitions and criteria used to delineate various disorders and whether some of these conditi... |
Do ticks or other blood sucking bugs (mosquitoes, etc) show preference to certain people? | Yes.
Both ticks and mosquitoes tend to target people by detecting the CO2 they release from their bodies, so perhaps your metabolic rate is higher than average and produces more carbon dioxide. Blood type O is preferred over A and B for them as well. Additionally, it could be that you were walking in front of them and ... | [
"Some species are blood suckers rather than predators, and they are accordingly far less welcome to humans. \"Triatoma\" species and other members of the subfamily Triatominae, such as \"Rhodnius\" species, \"Panstrongylus megistus\", and \"Paratriatoma hirsuta\", are known as kissing bugs, because they tend to bit... |
Why didn't the straight-pull bolt catch on in military service? | I can speak as to the difficulties encountered with the Ross Rifle, which was a Canadian, straight-pull bolt action rifle used at the start of WWI by the CEF:
The Ross was an incredibly accurate rifle, and was a fantastic hunting weapon, but the realities of trench warfare meant that the unreliability of the action be... | [
"The operating principle of the straight pull bolt action comprises a bolt \"sleeve\" to which the bolt lever or handle is attached. The sleeve is hollow and has spiral grooves or \"teeth\" cut into its inner surface in which slide corresponding projections or \"teeth\" on the outside of the bolt head or \"body\". ... |
How does photon-photon interaction not misconstrue the paths of other photon-photon interactions throughout space? | The short answer is that to a very good approximation photons simply don't interact with each other. To frame it a bit more technically, we would say that the [photon-photon scattering cross-section](_URL_3_) is extremely, extremely small. In other words, the photons of two crossing laser beams will quite literally jus... | [
"An intrinsic problem in using photons as information carriers is that photons hardly interact with each other. This potentially causes a scalability problem for LOQC, since nonlinear operations are hard to implement, which can increase the complexity of operators and hence can increase the resources required to re... |
How much oxygen does a candle use in a closed room? | Well first air is constantly diffusing in and out of the average room (via air ducts, cracks in doors/windows etc) so O2 is readily replaced. But for hilarity's sake lets assume we are in a perfectly sealed room or one where the air diffuses in more slowly than the candle would burn.
Its 1:30am here so please excuse ... | [
"A \"chlorate candle\", or an \"oxygen candle\", is a cylindrical chemical oxygen generator that contains a mix of sodium chlorate and iron powder, which when ignited smolders at about , producing sodium chloride, iron oxide, and at a fixed rate about 6.5 man-hours of oxygen per kilogram of the mixture. The mixture... |
How many senses do we have, I have heard there is more than the five children get taught | Humans have more than five senses. Although definitions vary, the actual number ranges from 9 to more than 20. In addition to sight, smell, taste, touch, and hearing, which were the senses identified by Aristotle, humans can sense balance and acceleration (equilibrioception), pain (nociception), body and limb position ... | [
"Children are often taught five basic senses: seeing (i.e., vision), hearing (i.e., audition), tasting (i.e., gustation), smelling (i.e., olfaction), and touching. However, there are actually many more senses including vestibular sense, kinesthetic sense, sense of thirst, sense of hunger, and cutaneous sense.\n",
... |
We know that matter is transformed in energy inside stars. Is there anything else on the universe that does the opposite, where energy is converted to matter ? | There are a few possible answers to this. For instance, depending on how you define matter (note that there is no strict definition of what matter is), a black hole could be an example. Light that enters the event horizon contributes to the rest mass of the black hole, so energy becomes "matter".
But if you want to fi... | [
"In cosmology and astronomy the phenomena of stars, nova, supernova, quasars and gamma-ray bursts are the universe's highest-output energy transformations of matter. All stellar phenomena (including solar activity) are driven by various kinds of energy transformations. Energy in such transformations is either from ... |
gold mines and supernovas | Most of the time is spent as dust in a cloud in the galaxy. It may form into bigger asteroids and small planets that may be ripped apart by a number of things. Eventually it arrives at the Earth. The reason gold is fond together in vanes is because similar materials with similar densities and other properties behave si... | [
"Goldbug was next hired by the Maggia to steal some gold from an Empire State University laboratory. He did so, not realizing that the gold had been exposed to radiation during experiments at the university, and that he had thereby contracted radiation poisoning. He battled Spider-Man, but when Spider-Man revealed ... |
what happens to throwaway accounts? | I think many don't actually throw their account away, since their only reason for creating one is to keep their main account free of the association with what they're posting/saying on their throwaway account. Most aren't ducking the authorities or any real investigation.
To my knowledge, there's no "throwaway" flag t... | [
"Another online method of cheating is \"multiaccounting\", where a player will register several accounts to his name (or, perhaps more commonly, to non-poker-playing friends and family members). This might be done to help enable the collusion previously mentioned, or perhaps to simply enable a well-known player to ... |
Least Expensive Firearms of the American Civil War? | For guns purchased in big numbers, rifled muskets were definitely cheaper, cheaper to supply with ammunition and more easy to service than breech loading guns ( which maybe is what you mean by "exotic"). According to the Ordnance Dept's statement of purchases from 1861-1866, certainly the few million mostly Austrian r... | [
"In 1869, the War Department purchased far fewer weapons of all kinds than it had in the Civil War. Only three Frank Wesson carbines were purchased during the year, for $20 each. At the same time, it purchased, or had modified 13,098 Sharps carbines (listed as 'Sharps carbines, altered'), at approximately $4 each.\... |
Why can humans control an involuntary action (breathing) but not choose to control your heart rate? | To my understanding you have skeletal muscle that can control your breathing, but smooth and cardiac muscles (which control heart rate) are involuntary. Although, controlling your breathing can actually indirectly control heart rate as well.
If you’re asking why specifically smooth and cardiac muscle can’t be controll... | [
"It is impossible for someone to commit suicide by simply holding their breath, as the level of oxygen in the blood becomes too low, the brain sends an involuntary reflex, and the person breathes in as the respiratory muscles contract. Even if one is able to overcome this response to the point of becoming unconscio... |
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