question stringlengths 3 301 | answer stringlengths 9 26.1k | context list |
|---|---|---|
market capitalization when it comes to purchasing a company. | Often the buying company must pay a premium to the traded price, to acquire the company, but usually this premium is 20-50% of the pre-offer share price.
One thing that isn't in the market cap but is usually part of the purchase price is the assumption of debt. If Kindred owed roughly $3.3 billion to its creditors, the purchase price could be $4.1 billion with only $800 million going to shareholders. The idea being the purchase of two otherwise identical businesses, one financed by mostly equity while another financed by mostly debt should probably have the same purchase price.
I didn't see the deal press release, but did find an article with this:
> Kindred, which had $7 billion in revenues last year, has been weighed down with *$3.2 billion in long-term debt.*
So Humana is paying $800ish million for the equity in Kindred Healthcare, but also will have to repay Kindred's creditors $3.2 billion. It's fairly common to include both of these when reporting the amount spent on a merger.
Whoa, thanks for the gold! | [
"Market capitalization equals the number of a company's shares outstanding multiplied by the market price of the stock. Market capitalization is an indication of the size of a company. Typical ranges of market capitalizations are:\n",
"If a company's stock price (which is a measure of the company's capital market... |
If everyone had a self-driving Google car, would there be a problem with interference between all the radars and lasers? | Probably not. Google “phase-sensitive detection” and you'll see how it's actually quite easy to recover your own signal from a sea of noise. | [
"Other systems similar to radar make use of other parts of the electromagnetic spectrum. One example is LIDAR, which uses predominantly infrared light from lasers rather than radio waves. With the emergence of driverless vehicles, radar is expected to assist the automated platform to monitor its environment, thus p... |
the difference between interpreted and compiled computer languages? | Compiled languages are translated directly into the machine code that the processor can execute. It would be like taking a cookbook written in Greek, and getting it translated to a cookbook written in English. Once you have the translated cookbook, you can then follow the recipes (as can everyone else that reads English).
Interpreted languages are translated on the fly. It would be like having a professional Greek interpreter sitting next to you, and you'd go "ok, what next?" and the Greek guy would be "Add half a cup of broth" and so on. The upside is that you didn't have to wait for him to translate the whole damn book, and if the original author makes changes to the book in Greek, you don't have to go retranslate it. The downside is that now whoever wants to use the recipe book has to have the Greek guy sitting next to them.
Compiled languages are usually faster to run, but they require a "build" step which can be time consuming, and is effectively when the translation to machine code is done.
Interpreted languages don't usually require a 'build' step, but they usually don't run quite as fast, because they need to have the interpreter there, translating everything as the program runs. | [
"The difference in code density between various computer languages is so great that often less memory is needed to hold both a program written in a \"compact\" language (such as a domain-specific programming language, Microsoft P-Code, or threaded code), plus an interpreter for that compact language (written in nat... |
why do manufacturers print "best before: see bottom" instead of the actual date? | It could be a case where the label is printed well before the product actually gets canned/boxed, so you cant put a date on the label as you don't know when it will actually be put on a product. So it directs you to where the date will be put during the final canning/boxing process. | [
"Sometimes the packaging process involves using pre-printed labels, making it impractical to write the \"best before\" date in a clearly visible location. In this case, wording like \"best before see bottom\" or \"best before see lid\" might be printed on the label and the date marked in a different location as ind... |
Have humans/organisms caused an increase on the overall mass of Earth? ie man made objects or birth of organisms? | Since all organisms on earth are created from the earth, (air, water, minerals) it is simply a redistribution of mass. We actually have reduced the mass by sending probes away from earth. Some is replaced by the constant in fall of inter solar dust and meteors but organisms do not add mass. | [
"The spread of the large and increasing population of humans has profoundly affected much of the biosphere and millions of species worldwide. Advantages that explain this evolutionary success include a larger brain with a well-developed neocortex, prefrontal cortex and temporal lobes, which enable advanced abstract... |
why in most us universities do they make you share a room with a roomate? | It's cheaper, and uses less space. I'm getting shafted enough already on rent in this two-person dorm room, I can't imagine what it would cost for everyone to have their own room. | [
"All of the rooms are rectangular double rooms. They do not have stackable or bunkable furniture, therefore if students want to loft their beds, they have to build or rent their own loft. Every room comes equipped with beds, dressers, desks with chairs, and closet space. They also include an Ethernet outlet and a p... |
Possibly the defining characteristic of Julius Caesar's legendary status as a general was the speed with which his army was able to operate- what accounted for this? What was he doing that other Roman generals weren't? Do we know how he was able to pull this off? | This has been asked before:
_URL_0_ | [
"The army of Julius Caesar focused on swift movements, celeritas, over spending time on full preparations. His approach to strategy is known to be one of great daring and risk. He subjected his men to dangerous winter marches and relied heavily on the crafting skill of Romans in quickly building siege weapons and f... |
why is devil's food cake not just called devil's cake? | there's two kinds of cake.
the first one along was called "[angel food cake](_URL_0_)".
then someone added chocolate to it, and made it into "[devils food cake](_URL_1_)".
because the second one was "devilishly good"
| [
"Devil's food cake is a moist, airy, rich chocolate layer cake. It is considered a counterpart to the white or yellow angel food cake. Because of differing recipes and changing ingredient availability over the course of the 20th century, it is difficult to precisely qualify what distinguishes devil's food from the ... |
why does alaska have so many lakes? | Glaciers receded during the ice age and tore up the land. Check out what most of the Canadian landscape looks like vs the lower 48 for a clearer example. Tons of tiny (and not so tiny) lakes everywhere. | [
"Alaska contains abundant natural resources which include ground and surface water. The southwestern part of Alaska is drained by the Yukon River and its tributaries that include the Porcupine, Tanana, and Koyukuk Rivers. The Yukon River is the third longest river and fourth largest drainage basin in North America ... |
Ancient Rome, Marriage, Sex | I'm on my phone so I'm just going to answer your last question here, and come back later for the rest.
In Roman law and morality adultery is defined only as sexuality relations between a married woman and a man who is not her husband. Therefore, a married man can have sex with anyone - male or female - except women married to another man. The punishment for adultery therefore is usually on the married woman, and is traditionally handled by a family council of her parents, grandparents etc headed by her paterfamilias or guardian (although as Richard Saller demonstrated in the 1990s the life expectancy of the Roman man was such that many women would be under the power of a guardian such as a service brother or family friend). Legally and technically the punishment was death, but due to the private nature of the judging body its very unclear how often women were actually executed for sexual crimes. It's probably pretty rare.
This was a pretty brief summary, but I will get back to the rest of your questions later :)
Nb. Qualifications are m.phil and phd in late roman and early christian marriage and sex ideologies :) | [
"Ancient Rome distinguished between two forms of marriage: the \"matrimonium non iustum\" and the \"iustae nuptiae\" (or \"iustum matrimonium\"). The former concerned a relationship between one man and one woman who intended to marry but could not do so in terms of Roman law; the latter dealt with formally recognis... |
Is there any consensus among historians on why Britain, in particular, became the birthplace of the Industrial Revolution? | This is a difficult question and my reasoning could be subjective in many aspects, I will cite my sources to justify my reasoning. For the industrial revolution to occur, people such as land and business owners had to be incentivised to invest in newer technology, otherwise there would be no reason to invent.
**Starting the Revolution:**
That incentive came with the [British Agricultural Revolution](_URL_0_) (Which I will try to summarise), which saw rich people acquire the communal land which peasant farmers often used. The most efficient method of farming until the 1700's was the three year crop rotation plan, which saw a plot of land divided three, two used to grow crops and one given a years rest to revitalise the soil, usually occupied by grazing animals of perhaps another farmer (Grazing animals generally boosted the crop productivity of the plot).
The Second Viscount of Townsend, Charles Townsend served as the British ambassador to the Netherlands from 1709-1711, where he observed Dutch farmers using a four year plan of wheat, turnips, barley and clover, where the turnips would re-nitrate the soil doubling the productivity of the plot, and clover would be used as pasture resulting in high yields for the next few years. When he came back to Britain, he popularised the widespread use of the technique. It's important to note that the technique was used in Britain, just not widely.
[Enclosure](_URL_5_) was essentially the privatisation of the communal land which the farmers used. As an analogy, imagine you and a few other people each control a small plot of land, each of you plant crops by hand because it would not be cost effective to acquire technology to help as your revenues simply aren't high enough and your plot is too small to make it worthwhile. Now a wealthy individual acquires the land which you and a number of others use and merges them into one farm. it would be simply too hard for that individual to seed it all by hand, so they employ the use of technology, specifically the [seed drill, refined by Jethro Tull](_URL_2_) in 1700.
Someone is using technology, food output is dramatically increasing population, and suddenly you and those few other people are out of work, resulting in massive amounts of urbanisation throughout the 1700-1800's, travelling to cities to work in textile (England monopolised cloth into Europe from the 1500s) and steel mills, as well as coal mines for very small wages (pretty much, lots of people are very cheap to hire) - it's no coincidence that some of the most [populous cities in Britain](_URL_1_) are built atop of [coal](_URL_4_) and iron fields and had a large manufacturing sector.
**Sustaining the Revolution:**
Wealth and materials are required for invention;
Imperial preference was employed by the British upon her colonies - free trade within the empire, and tariffs when trading outside the empire. Now I must direct you to historian and politician *Shashi Tharoor's Inglorious Empire,* where he, although not the main point of the book, argues that "Britain's industrialisation was built on India's de-industrialisation." for two thousand years India had been the producer of exquisite cloths, originally produced in Bengal, which sent wealth from Europe and the Middle East to India through trade. With the "colonisation" of India, she could no longer export her manufactured goods favourably (Britain banned the importing of Indian cloth, putting many out of business), and became an exporter of raw materials and an importer of manufactured goods, now including British textiles which soon overwhelmed the Indian markets and sent hundreds of years of wealth in the region back to Britain, as well as endless amounts of raw materials. Wealth and raw materials being siphoned to Britain also applies to her other colonies, but I'd argue that India was the most important, being the populous, industrialised and \[formerly\] wealthy - the Jewel of the Empire. (**Edit:** This said, please read the important points u/ReaperReader has mentioned below)
Britain maintained political and economic stability, her heartland being protected by The Channel from foreign threats such as Napoleon.
**Why not ...?**
Iberia lacked resources. Spain primarily produced goods with high retail value, like sugar, and gold to finance wars in Europe rather than to build economic power. They also suffered political instability following their bankruptcies. While they were an agricultural economy, they really lacked the incentive (slavery, very little industry).
France had a religious intolerance, and many great thinkers were protestants. There was a bit more religious freedom in Britain, in the case of Denis Papin, he left France for Britain and ended up inventing the precursor to the pressure cooker (Originally used to create fertilisers such as bone meals). They also suffered political instability through the 1700s.
It's very well a possibility that the [Dutch](_URL_3_) could've hosted the revolution. The Republic of the Seven United Netherlands were the first to industrialise after Britain, however they had a relatively small population and high wages.
India (Various princes). The fall of the Mughals created regional instability and the East India Company's invasion didn't help the situation financing themselves with Indian plunder.
China had stability wealth and population, but the people were not concerned with increasing economic output, was more concerned with philosophies and culture, nor had the thinkers of the time.
To sum it up, a population boom and high urbanisation made allowed the production of enough goods and made them large enough for businessmen/farmers to invest in inventions, high amounts of wealth, materials and need for better efficiency increased the output of ideas and inventions, as well as the fact that Britain was highly educated and had public libraries. | [
"British economic historian Gregory Clark has controversially claimed, in his book \"A Farewell to Alms\", on the basis of extensive research, that Britain may have been where the Industrial Revolution began because the British people had a head start in \"evolving\"through a combination of cultural and possibly ev... |
what are farm subsidies and how do they work? | Okay, so for years the United States produced more cotton than any other country. So anyone in other countries who wanted cotton would end importing it from the United States.
All was well, and the cotton farmers had a great time, since everyone was paying top dollar for their cotton.
Now, for a number of reasons that I'll explain when you're older, other countries suddenly were able to grow and sell cotton for cheaper than the United States. This was very bad news for American cotton farmers, who couldn't compete with the cheap cotton coming from other countries.
So, the cotton farmers said Help! Please, government, can you do something? Our business is in danger, and as you can see, the United States relies on all the business the cotton trade brings in! Please do something!
So, the government says "Well, you're right, this cotton industry is too big to fail. What we'll do is we'll pay you some money each year so that you can lower the prices of your cotton." This way, people don't start buying Brazilian or Egyptian cotton, the US cotton is cheaper for them.
This is sorta short-sighted though. The government is propping up a business that can't keep itself afloat, and everyone who pays taxes ends up paying a bit of their money each paycheck so that US cotton is cheaper than imported cotton.
Now this has happened in other industries as well. Wheat, corn, oil, and a bunch of other things are all heavily subsidized, so that your bread and gasoline are cheaper and so that you don't have to buy imported goods, keeping the money inside the country, and creating jobs for Americans. This is of course silly and unsustainable.
This causes other weird stuff like for instance if one year everyone grows too many pigs, the price of pork will drop too low, so sometimes the government will come in and pay the farmers to kill their pigs and bury them, so that they don't suddenly flood the market with cheap pork, putting some people out of business.
Now, it gets even weirder. Since sugar is so hard to produce in America, and it's so easy to grow in the tropics, instead of subsidizing American sugar, we put tariffs on imported sugar. That means, there's an extra tax on sugar that you get from other countries. That combined with the fact that corn is subsidized by the government means that people who make sweet foods have switched away from using real sugar, and instead use high fructose corn syrup. All kinds of weird things like that happen when the government artificially interferes with the prices of goods.
Now, to make things *even* weirder, back to the example of cotton.. All of the sudden Brazil, who we trade with a lot, says "Hey, you guys are subsidizing your cotton so it's too cheap, so we are unable to sell our Brazilian cotton. Do something about that or we won't trade coffee (for example) with you!"
The sane thing to do might be to lower the subsidies given to US farmers, but those are written into contracts that couldn't be broken at the time, so what they did instead is subsidize Brazilian farmers! That's right, the some of the tax dollars that US citizens pay off of every check goes to Brazilian cotton farmers so that they can lower the prices of their cotton, so they can compete with the unfairly low prices of US cotton! Imagine that!
| [
"An agricultural subsidy is a governmental subsidy paid to farmers and agribusinesses to manage the agricultural industry as one part of the various methods a government uses in a mixed economy. The conditions for payment and the reasons for the individual specific subsidies varies with farm product, size of farm, ... |
Do we know anything about siege weapons and siege warfare in Native American societies? | While waiting for further comments, check out [this earlier thread](_URL_0_) on warfare and sieges in the New World. | [
"In the 1990s and early 2000s an influential group of archaeologists, led by Steven A. LeBlanc of Harvard, popularized the notion that warfare was endemic among all prehistoric peoples. Koblitz analyzed the writings of this group, compared them to other sources, and concluded that the claim of pervasive warfare amo... |
How long would it take for Earth's orbit to be affected if the sun were to suddenly blink out? | The effect of gravity does travel at the speed of light, so the earth would cease to orbit, and travel in a straight line after 8 minutes 20 seconds. | [
"In December 2012, a research team in China announced that it had produced measurements of the phase lag of Earth tides during full and new moons which seem to prove that the speed of gravity is equal to the speed of light. This means that if the Sun suddenly disappeared, the Earth would keep orbiting it normally f... |
What is the biochemical mechanism by which smoking reduces bone density? | From the national institute of health, "Analyzing the impact of cigarette smoking on bone health is complicated. It is hard to determine whether a decrease in bone density is due to smoking itself or to other risk factors common among smokers. For example, in many cases smokers are thinner than nonsmokers, tend to drink more alcohol, may be less physically active, and have poor diets."
Or in other words no one knows for sure. | [
"BULLET::::- Tobacco smoking: Many studies have associated smoking with decreased bone health, but the mechanisms are unclear. Tobacco smoking has been proposed to inhibit the activity of osteoblasts, and is an independent risk factor for osteoporosis. Smoking also results in increased breakdown of exogenous estrog... |
Do human skeletons retain their death pose? | Rigor mortis would likely change the position, and as tendons dry up they would pull the skeletal structure into different positions; you've almost certainly seen this in fossil imprints where a creature's head is bent backwards. Consider [this](_URL_0_) image.
| [
"Animated human skeletons have been used as a personification of death in Western culture since the Middle Ages, a personification perhaps influenced by the valley of the dry bones in the Book of Ezekiel. The Grim Reaper is often depicted as a hooded skeleton holding a scythe (and occasionally an hourglass), which ... |
why do media organizations ask for user permission before sharing submitted content from twitter but not reddit? | If you submit a link to Reddit, it's from an external source/site. Just because you shared it doesn't mean it's yours so there is no reason to ask permission from anyone on Reddit. You'd ask the owner of the original source of the link.
Text posts and comments are easier to use under fair use - especially since you can paraphrase the original post. You can't paraphrase a video or photo of an important event, so they explicitly ask permission for things like that.
Either way, I commonly see Reddit and Reddit usernames referenced in online news/articles as sources. | [
"This campaign’s goal is to urge Internet users to join organizations by signing a petition in regards to Internet surveillance and censorship. OpenMedia claims that individuals should have their rights to embrace anything online.\n",
"BULLET::::- Twitter: The Twitter Terms of Service state: \"We reserve the righ... |
A good source for causes WWI? | Definitely make sure to check out the /r/AskHistorians Booklist, [which has an extensive section on this!](_URL_0_) If you find yourself better suited to listening, many of those books should be available as Audiobooks. | [
"Sidney Bradshaw Fay (13 April 1876 in Washington, D.C. – 29 August 1967 in Lexington, Massachusetts) was an American historian, whose examination of the causes of World War I, \"The Origins of the World War \" (1928; revised edition 1930) remains a classic study. In this book, which won him the 1928 George Louis B... |
How did the vacation practices of Western Europeans differ from Eastern Europeans during the Cold War? | Not sure about the rest of Eastern Europe, but in the Soviet Union, you couldn't easily travel abroad without a special permission or a work assignment. Especially to non-communist countries. However the USSR was a large enough country that there were still plenty of places to vacation within the country. The Black Sea coast was known for its summer resorts, as well as the Baltic. One could take a cruise up and down the Volga river to see historic central Russia. The Caucasus Mountains and Central Asia were good places to hike.
More locally, it was popular to go a nearby forest and collect berries, mushrooms, etc, usually as a day trip on a weekend. Some of the better off people had "dachas", or summertime shacks in the countryside. A dacha would usually have a small plot of land attached to it where one could do some gardening. So during the summer people who had them would be at their dacha on weekends. Children would often spend their summers at a summer camp. | [
"Varna became a popular resort for Eastern Europeans, who were barred from travelling to the west until 1989. One of them, the veteran German Communist Otto Braun died while on a vacation in Varna in 1974.\n",
"During the post-World War I period ski-lifts were built in Swiss and Austrian towns to accommodate wint... |
the difference between gaelic, welsh, breton, and manx | Since you are five, let's pretend that English, [Gibberish the language game](_URL_1_), and Pig Latin were all languages you knew. They are all pretty closely related, but you can pretty much immediately understand Pig Latin and English since there really isn't much difference. Gibberish on the otherhand is still based on English but there are many more syllables so it's much harder to understand. Now you speak Pig Latin. Your neighbors on the other hand speak Gibberish but never learned English. You can probably listen and catch onto some of the words but if you don't know the bits of grammar it probably won't make sense to you. The same would be true of all the languages you listed. In that they all came from a common source, however, they are different based on the area where the developed. In this case, it was your house and your neighbors house.
[Here's an example of someone speaking Gibberish if you are interested.](_URL_0_)
More like you are fifteen: there are two branches of Gaelic, Brythonic and Goidelic Gaelic. They would have all come from a Proto-Celtic language. I'm assuming when you say plain old Gaelic that you are referring to Irish Gaelic which is of the Goidelic branch. Breton and Welsh are the only two languages of the Brythonic branch of Gaelic. There were other Gaelic family languages that are no longer spoken.
The big difference between the two is that Brythonic languages generally were spoken in Southern Great Britain as well as small enclaves on mainland Europe, whereas, Goidelic languages tended to be spoken in northern Great Britain and Ireland. That is other than the obvious bit about the vocabulary being different. Since you are five, Goidelic languages will share more common words and vocabulary with each other. Whereas Brythonic languages will have the same. However, Goidelic and Brythonic langauges will have much less in common with each other.
Back to the geography based differences. Those that speak the Brythonic languages are Celts but they are not Gaels. Those that speak Goidelic languages are both Gaels and Celts. | [
"Although Irish and Manx are often referred to as Irish Gaelic and Manx Gaelic (as they are Goidelic or Gaelic languages), the use of the word \"Gaelic\" is unnecessary because the terms Irish and Manx, to refer to language (as in, \"to speak Irish\"), always refer to these languages, but Scots has come to refer to... |
Why do pigeons walk the way they do? | [The head bob allows them to hold their head still (relative to their surroundings\) for as much time as possible](_URL_0_). This probably makes them better able to observe their surroundings. | [
"Pigeons are meek and gentle with soft feathers which follow humans well. They symbolize the peace and security of mankind, and they mean to desire the unification of the Korean Peninsula and the well-being of citizens.\n",
"Other research indicates that homing pigeons also navigate through visual landmarks by fo... |
how come native americans never built empires like cultures on other continents? | Near St Louis is Cahokia. There are Mounds several stories high that were built by a large civilization. Several thousand Indians thrived there.
_URL_0_
More information : apparently it was one of the largest civilizations between 600-1400AD | [
"Each colonial power has certain bonuses that make them unique and different from each other. Aside from European colonial powers, the NPC powers include eight Native American tribes, in four main categories. Each Native American settlement can convert one regular colonist into a specialist. More advanced tribes (I... |
In evolution, why do certain traits develop that seem helpful but not essential to survival? | It can sometimes be deeper than this.
For example Cystic Fibrosis is a genetic disorder that shortens life span significantly. Why then do 1 in 25 people in Britain carry the recessive allele? Surely evolution would have killed it off?
The answer is that Not so long ago (in the evolutionary time scale) Britain was ravaged by the Black Death. If you are a CF carrier you have a significantly thicker layer of mucus than people with no CF gene. This made the virus that caused the Black Death was less likely to make it into the body. This meant that actually if you were just a carrier you were more likely to survive this deadly disease. And because this disease killed so many people in Britain the results of nature's selection for it (even though it shortens life spans when there is no respiratory disease) is still observable.
I know that CF isn't in the category of things you are asking for but I am just saying sometimes it takes a deeper look into the subject. | [
"The dictionary definition of Evolution is any process of formation, growth or development. In biological evolution the main principle behind this development is survival, we evolved to become stronger and quicker, we also evolved to become intelligent. But as we became intelligent biological evolution subsided to ... |
When the brain receives a nerve signal from the skin, how does it differentiate between a heat signal, a cold signal, a pain signal, a pressure signal etc? | Different neurons in the skin are used to detect different sensations, and the frequency of the signals they send determines the intensity of the sensation. Different parts of the brain take in different signals so we can distinguish different sensations from each other | [
"The auditory nerve carries the signal generated by the hair cells away from the inner ear and towards the auditory receiving area in the cortex. The signal then travels through fibers to several subcortical structures and then to the primary auditory receiving area in the temporal lobe\n",
"These neurons have se... |
Skim, 1%, 2%, whole milk? Soy milk? Almond milk? Coconut milk? Nutritionally speaking, what's the best kind of milk to drink? | In relation to Calcium I can tell you that you require 1500-2000 mg (1.5-2 grams) a day, making Calcium the highest requirement micronutrient/mineral required. All types of milk generally have the same amount of Calcium in them.
However, this is due to the addition of Calcium in Soy/Almond/Rice/Coconut milk, as non-dairy milk has very little to no Calcium in it already. Soy milk being the exception, it does actually have a significant amount of Calcium (but still up to 5-6 times less than dairy milk).
Milk often has Vitamin D added to it, as Calcium uptake has been shown to be enhanced by Vitamin D (When consumed at near the same time. This is has been shown with Iron and Vitamin C as well).
Other nutrients are generally a wash. (I.e. B12 is marginally higher soy, omega-3's are about the same usually. Note that Omega 3's from fish are healthier than those from flax/milk. [1]) My studies didn't me far beyond Calcium, but Phosphorous was mentioned (~25-30% DV in Dairy milk to 0-10% in Non-Dairy milk), the K / Ca element balance is important to your body (although they are found in ion form in your body, in case anyone cares).
Some proponents of soy milk argue that it is not a wash, and soy milk has significantly more micronutrients than milk. I haven't much research on this, besides looking at 2-3 comparisons, none of which seemed very conclusive. (I.e. It didn't pertain to my area of research, so pubmed/JSTOR were left untouched). A more full answer might be found if you kept this in mind =)
In terms of fat, for a NA diet, Skim Milk wins out by a long shot. In almost all households you will already be eating enough, if not too much, fat. I am simplifying the concept of "fat" here because I have to leave for lab work =(
As a side note, what napmeijer said is unfortunately **wrong**. Antibiotics are used on many dairy cows to destroy their resident bacterial flora, this causes none of their intake of food to be feeding bacteria, and thus is more efficient feeding. In the U.S. up to 50% by weight of all antibiotics are fed to farm animals. It has very little to do with disease. It should be noted that while Europe has better antibiotic regulations than NA has, by far, no cutting edge antibiotics are used, and very little health concerns have risen from antibiotic use in animals
so far, although the potential danger is there.
On the whole skim milk is "healthier" in that on an already balanced diet, it is preferred to drink skim milk. However, if your diet is lacking in fats, then milk with more fats can supplement it nicely.
TL;DR: Milk choices should be personalized, but skim is "healthiest".
Followed by soy.
[1] You can research Alpha-Linoleic Acid if you wish =) | [
"Coconut milk is a rich source (20% or more of the Daily Value, DV) of manganese (44% DV) and an adequate source (10–19% DV) of phosphorus, iron, and magnesium, with no other nutrients in significant content (see table).\n",
"In 2016 in the United States, the Food and Drug Administration (FDA) amended food additi... |
Is the lack of snow in North America an effect of Global Warming? | Two things.
1) The lack of snow, if anything, would be a symptom of global warming not a cause. AKA more heat = less snow.
2) The local weather is influenced far more by local meteorological trends (highs, lows, fronts, etc.) than by global warming. It's like dipping a cup into the ocean trying to find a specific fish, you're just looking at too small of a sample to find it. So no, the lack of snow in the US would be better explained by other phenomena than by global warming. | [
"Shorter winters and longer growing seasons may appear to be a benefit to society from global warming, but the effects of advanced phenophases may also have serious consequences for human populations. Modeling of snowmelt predicted that warming of 3 to 5 °C in the Western United States could cause snowmelt-driven r... |
How big is the area of sky we look at during the day? | **It depends on your height and how far into the sky you are looking.** I assume you mean "Due to the atmosphere we can only look so far", this I'll not be able to clarify for you. Part of your question can be answered with math though.
If we assume you are at sea (the most uniform horizon) and your elevation is 0, then you'd be able to see 180 degrees of sky because your line of sight is tangent to the bending of the earth. However, the earth is not 2D, it's 3D, so if we draw a line through the centre of the earth, through you and up into the sky, we can establish the 2D environment by saying you look at 90 degrees at a time, times 360 degrees all around you. (if we say it's 180 and then all around you, we'd be counting the same space twice), so it's 90*360 degrees of space.
The moment you stand up things get a bit more complicated, because you'd be able to see further into the horizon, thus, more of the sky. Luckily, the angle at the horizon is 90 degrees to the centre of the earth, so it's super simple to calculate. [Nicely illustrated by the drawing in this article (beware, his calculations are very approximate and based on false information)](_URL_4_).
[I use this calculator](_URL_2_) and [This article shows the average distance to the centre of the earth](_URL_1_) at 6371km [(same as wiki says)](_URL_3_)
If you are in a boat standing up, let's say your elevation is 2m
then you'd be able to see the horizon 5.05km away. I plot in 6371 as side b, and 6371.002 as side c (and angle C at 90 degrees). Your angle of sight between the centre of the earth and the horizon is then what's here called "Angle 3", (which is actually angle B). At two decimals it's 89.95 degrees. Now imagine the line going straight up from the centre of the earth and into the sky above you and you are looking due east. There is 180 degrees between these lines going through you but 89,95 of those are earth, so the remaining 90.05 is sky. Now take this and spin a circle, you get the additional 360 degrees. The higher you get the closer the angle between the centre of the earth and the horizon get's to 0, without ever reaching it. So the higher you are up, the more of the sky you'll be able to see. (+ maybe you can see further into the atmosphere).
Edit: Athhmosphere..
Edit 2: [Here is a calculator for sphere surface area.](_URL_0_). you can clearly see an airplane which I believe fly at a height of approximately 10km. If you plot in 10000m as your radius, the surface area is 1256640000m^2. If we assume your elevation is 0 you just divide it by 2 and get the surface area of the sky, which is 628320000m^2 which is 628320km^2 so well over half a million square kilometers. Note: I believe you're able to see much further. | [
"The location of α Andromedae in the sky is shown on the left. It can be seen by the naked eye and is theoretically visible at all latitudes north of 60° S. During evening from August to October, it will be high in the sky as seen from the northern midlatitudes.\n",
"It is planned to survey the entire accessible ... |
If humans can see ants at our current sizes, would we be able to see germs, cells, etc. if we were ant size? | When we say we "see" something, we mean that we can "[resolve](_URL_0_)" the object, i.e., we can clearly identify the object as being at that position with that brightness etc. If the object is not resolved, then depending on how poor our resolution is compared to the object's size, it will range anywhere from appearing blurry to looking like nothing against the background.
So to see smaller and smaller objects, we need to be able to resolve these small objects. A fundamental limit imposed by physics is that the resolution of any system (eye, camera, telescope) is limited by the size of the "aperture", or collecting area for the light. So the larger the aperture, the better your resolution, and you will be able to see smaller and smaller things
**To finally get to your question:** If we shrunk down to the size of an ant, our eyes would also shrink, so our resolution would get comparitively poorer. So it's unlikely we will be able to see things an order of magnitude smaller than us like cells, or organelles in a cell or whatever. The best way to do that is to get a larger aperture. So use a microscope, or grow a larger eye. | [
"\"Myrmecia\" ants are easily noticeable, due to their large mandibles, and large compound eyes that provide excellent vision, and a powerful sting that they use to kill prey. Each of their eyes contains 3,000 facets, making them the second largest in the ant world. Size varies widely, ranging from in length. The l... |
why is it illegal to use milk crates for other things aside milk? | I didnt know that. At my job we go into the dairy cooler and grab milk crates for other purposes every day. | [
"It was held that (1) the ban on plastic nonreturnable milk containers was rationally related to the achievement of legitimate state purposes and thus did not violate the equal protection or due process clauses of the Fourteenth Amendment, since the state legislature could rationally have decided that its ban on pl... |
What is the evolutionary advantage of the poppy plant to produce morphine? | Alkaloids like morphine, nicotine, caffeine, and many more act as [insecticides](_URL_0_) for the plant in nature. Their effects on us are a bit of a natural accident. | [
"The opium poppy was cultivated in lower Mesopotamia as long ago as 3400 BC. The chemical analysis of opium in the 19th century revealed that most of its activity could be ascribed to the alkaloids codeine and morphine.\n",
"Today, morphine and codeine are common alkaloids found in several poppy varieties, and ar... |
why do companies pay ceo's so much money? | 1) CEOs spend a lot of time working, so they need to be compensated. They are held responsible for the company, so 24/7 they are on the hook and often answer calls in the middle of the night, skip weddings and kid's soccer games, and don't have meaningful time off.
2) There are only so many experienced CEOs. There are millions you could hire to fry chicken at KFC, but only a handful of individuals who have experience running multinational corporations that employee tens of thousands of people. A small pool means more negotiating power for those in it. | [
"Economist Krugman argues that while in theory differences in quality of a CEO can be worth millions of dollars to a company and therefore justify millions in dollars of pay, in practice it is very hard to set pay according to performance because of:\n",
"Management's desire to be paid more and to influence pay c... |
Could a diamond be considered a massive molecule? | I's technically not considered a massive molecule, as it doesn't have an identifyable shape or size. They tend to be better described by how other crystalline structures form: in "cells" that are repeating patterns of with the same structure that can be joined together and repeated.
It does depend on your definition of a molecule though, if you're taking the meaning as a number of atoms with intra-molecular bonds then you could consider it a molecule. | [
"Diamonds may exist in carbon-rich stars, particularly white dwarfs. One theory for the origin of carbonado, the toughest form of diamond, is that it originated in a white dwarf or supernova. Diamonds formed in stars may have been the first minerals.\n",
"Although diamonds on Earth are rare, extraterrestrial diam... |
so what exactly is the connection between nazism and the composer richard wagner? | Wagner wasn’t a Nazi, because he died in 1883, before Hitler was even born. But in his time, Wagner was a virulent anti-Semite.
Hitler and the Nazi Party loved Wagner, however, and the composer and his beliefs conflated with Nazism and anti-Semitism.
[BBC source ](_URL_0_) | [
"The German composer Richard Wagner was a controversial figure during his lifetime, and has continued to be so after his death. Even today he is associated in the minds of many with Nazism and his operas are often thought to extol the virtues of German nationalism. The writer and Wagner scholar Bryan Magee has writ... |
Do we know exactly what would've been hit had the cold war gone hot? | Not exactly. First of all, the targets, strategies, and capabilities varied by time period. So the answer for 1962 is not going to be the same for 1983, for example. Second, the exact targets have tended to be classified. Occasionally there are ways to glance at that information, e.g., a list of possible targets in the USSR used for weapon requisition purposes [was released by the US recently that gives some impression of what kinds of things they considered a target](_URL_0_). But it did not indicate priorities, how many weapons would be assigned to each target, the type or size of the weapons, the method of delivery, etc.
We do have a pretty good guess as to what the US thought the USSR would target if the USSR was using US targeting strategies, though. Note this is several leaps from knowing what the Soviets would do. But the US assumed the USSR would target all nuclear facilities (counterforce), any airfields that could be converted to military use (almost all of them), large power plants, sites of heavy industry, and so on. So that's a pretty big list in and of itself.
We do have some indications about some of the historical war plans for the US. Generally not to the detail of specific targets but bulk information about how many targets, how many megatons assigned, whether you could choose not to target China or not (in the early plans, you could not), and so on.
It's necessarily a speculative game in any case — war is chaotic and contextual. We can see the rough outlines of what it might look like. | [
"BULLET::::- 1947–89 – Cold War, an era of high tension and hostility—but no major \"hot\" war—between the US and its allies (Western Europe, Canada, Japan, etc.) and the Soviet Union and its satellite states.\n",
"Cold War — An examination of the strategic conflict between the United States and the USSR in the s... |
why does certain bacteria cause food poisoning that makes you expel basically everything in your digestive system? | Some bacteria, as a byproduct of their metabolism, produce a toxin. This toxin and its source, when detected by our bodies is *gotten rid of* as quickly as possible via explosive bowel movements. | [
"In the foregoing, there was mention of bacteria contaminating foods that cause infection in or from the digestive tract. Other food-borne bacteria can cause disease by producing toxins. It is no longer about infection, but toxication. Among these bacteria, some synthesize a toxin only when their concentration in t... |
Where would you have to be standing on Earth such that you were furthest away from the Earths centre? | The summit of [Chimborazo](_URL_0_), Ecuador. | [
"On a completely flat Earth with no visual interference (such as trees, hills, or atmospheric haze) the ground itself would never obscure distant objects; one would be able to see all the way to the edge of the surface. A spherical surface has a horizon which is closer when viewed from a lower altitude. In theory, ... |
why is identifying as another gender ok but identifying as another race crazy? | _URL_0_
_URL_1_
_URL_3_
_URL_2_
| [
"Some researchers believe that the difference in scores for both race and gender is closely related to psychological phenomenon known as stereotype threat. Stereotype threat happens when an individual who identifies themselves within a subgroup of people, is taking a test and comes across a stereotype (usually of A... |
What force balances gravity when I spin a belt/cord/rope above my head in a circular motion? | Good question. This is a problem often addressed in a first year mechanics class. It is the tension in the string which balances the force of gravity, and that tension is determined by the string's weight and how fast the string is spinning - spinning faster means more tension, according to the centripetal force law. For low tension (spinning slowly) the centripetal force is small compared to the weight of the string, so the string is close to parallel to the direction of the gravitational force (perpendicular to the floor). For high tension (spinning fast) the centripetal force is large compared to the weight of the string, so for the component of tension in the opposite direction to gravity to balance out gravity, the string needs to be spinning close to, but not quite, perpendicular to the gravitational force. Try it for yourself - spinning the string faster and faster (in a safe way!) will cause it to become closer and closer to horizontal. | [
"Precession can be demonstrated by placing a spinning top with its axis horizontal and supported loosely (frictionless toward precession) at one end. Instead of falling, as might be expected, the top appears to defy gravity by remaining with its axis horizontal, when the other end of the axis is left unsupported an... |
why objects smaller than the wavelength of visible light can't be seen by a regular microscope | Imagine that you are tasked with building a realistic statue of a man. The only materials allowed are Legos. Done well, the statue will look fairly realistic. Now, build the same statue with concrete blocks. Can it even resemble a man? No, the pieces are too big. It's the same with light. If you are trying to resolve an image of something, what you are using must be smaller than the object being imaged. The closer the imaging medium's size approaches the size of the object, the resolution diminishes and disappears entirely when the sizes match. Electrons have a smaller wavelength than visible light, and therefore electron microscopes can resolve smaller objects. | [
"Optical microscopes can focus on objects the size of a wavelength or larger, giving restrictions still to advancement in discoveries with objects smaller than the wavelengths of visible light. Later in the 1920s, the electron microscope was developed, making it possible to view objects that are smaller than optica... |
how do they count all those bees when news headlines say 37 billion dead bees? | They send people out to count them all
Just playing, Basically, they (whoever released the information) judge how many bees died by what they know about bees, and what they can observe. Bees act a certain way, weigh around a certain amount, etc. They would most likely find the rough area of where the bees died, and how close to each other they are on the ground. this would give you a rough amount, say, 37 billion. The headlines are estimates, and generally are exaggerated. I don't have many facts to back up my information, its mainly speculation based on the scientific method. I hope I made sense. | [
"According to the European Food Safety Authority (EFSA), in 2007, the United Kingdom had 274,000 hives, Italy had 1,091,630, and France 1,283,810. In 2008, the British Beekeepers Association reported the bee population in the United Kingdom dropped by around 30% between 2007 and 2008, and an EFSA study revealed tha... |
Do magnetic and/or electric field have any influence on time and space? | As other people have pointed out, the answer is yes, but there’s something in the way you phrased the question I want to focus on. You said that gravity curves spacetime, and wondered if other forces do as well.
It’s much more accurate to think of matter and energy as curving spacetime, and this effect is *itself* gravity. Gravity *is* spacetime curvature. So in that sense it’s on a different footing than the other forces.
All of the forces are carried by fields - for example, the electric and magnetic forces are carried by the electromagnetic field - and fields have energy, so they do curve spacetime, which is to say, they gravitate.
EDIT: I should add this effect is absolutely tiny unless the strength of the electric or magnetic field is absolutely enormous.
EDIT EDIT: Probably the most famous (theoretical) example of this effect is a charged black hole. The spacetime curvature around such a black hole is different than for an uncharged one. That is to say, charged and uncharged black holes gravitate differently. This is *in addition to* the electromagnetic force that charged black holes have. | [
"According to Maxwell's equations, a spatially varying electric field is always associated with a magnetic field that changes over time. Likewise, a spatially varying magnetic field is associated with specific changes over time in the electric field. In an electromagnetic wave, the changes in the electric field are... |
Can rocks evaporate? | Sulfur does. In thermal vents around volcanoes, you can find deposits of sulfur that has sublimed from below and been deposited in the cooler upper regions of the vent.
Here's a [picture](_URL_0_) of it. | [
"BULLET::::- Evaporite sedimentary rocks are composed of minerals formed from the evaporation of water. The most common evaporite minerals are carbonates (calcite and others based on ), chlorides (halite and others built on ), and sulfates (gypsum and others built on ). Evaporite rocks commonly include abundant hal... |
Is there significant risk of infection from fecal
bacteria if there is an open cut on the anus? | While this isn't the exact area of my research, I searched around on pubmed to see if this appears to be a well studied problem, and I found very little information, suggesting that infection with fecal bacteria of these kinds of wounds is not a common concern, or it is understudied or possibly irrelevant to treatment. On wikipedia I did find one [statement](_URL_3_) suggesting that infection with bacteria from the gut could occur and cause problems such as ulcers that will not heal. While I didn't find an articles specifically backing the wikipedia statement up, in general as your skin is your body's first line of defense against infection, any cut in it would place you at a higher risk. Still, it may be interesting to note that even if they are not infected, these sorts of injuries can continue to progress for months and worsen over time requiring increasingly specialized care ([source, NSFW](_URL_0_)).
While I didn't find much suggesting anal fissures could become infected, I did find quite a few sources that suggested bacteria and viruses could cause fissures and absesses (see previous source). Some of the bacteria included among those that could cause infection were E. coli and Bacteriodes, organisms commonly found in the gut which usually are not pathogenic. This seemed to me to suggest that there may be a possibility that some wounds could become infected with these organisms after they occur, though again, there was not specific source for this. Other causes of anal fissures include stds such as Treponema pallidum (causes syphillus) and organisms that typically infect other areas of the body such as [Mycobacterium tuberculosis](_URL_1_).
It is also interesting to note that even without breaks in the skin, gut microbiota can cause disease. While rare, in some instances, bacteria can [translocate](_URL_2_) across the intestinal mucosal barrier. More commonly, bacteria, especially E. coli, from your intestines can enter your urethra causing a urinary tract infection.
| [
"Abscesses are caused by a high-density infection of (usually) common bacteria which collect in one place or another for any variety of reasons. Anal abscesses, without treatment, are likely to spread and affect other parts of the body, particularly the groin and rectal lumen. All abscesses can progress to serious ... |
Did dinosaurs, like reptiles of today, molt or shed their skin? | It depends on the dominant integument (body covering) of the dinosaur in question.
**Feathers:** There is good evidence to indicate that feathered theropods with pennaceous (vaned) feathers molted as they grew, much in the same way that birds do today. Although hatchlings of the oviraptorosaur *Similicaudipteryx* bore pennaceous tail feathers at birth ([Xu et al., 2010](_URL_4_)), immature specimens have a peculiar "ribbon-like" feather morphology that drastically differs from the feathers of adults. These represent molting feather germs undergoing development, and look identical to the same kind of feathers in modern birds ([Prum, 2010](_URL_2_)).
**Scales:** The ancestral state of dinosaurian scales probably would have been relatively close to crocodilian integument in molecular composition (i.e. the specific alpha- and beta-keratin structure that they were composed of). See the work of Greenwold and Sawyer (e.g. [Greenwold & Sawyer, 2013](_URL_1_)). Crocodiles do not molt in the same way that squamates do, where the entire integument is replaced at once. Thus, it would be reasonable to assume that the same held true for early dinosaurs.
**Secondarily-derived scales:** Some molecular ([Dhouailly, 2009](_URL_0_)) evidence indicates that the reticulate and scutellate scales on the feet of birds, non-avian theropods, and possibly ornithischians ([Cuesta et al., 2015](_URL_3_)) may have been secondarily derived from feathers (or protofeathers). If this was indeed the case, and applied more generally to scalation across the entire body - a highly speculative assumption - it may be possible for some molting (incl. replacement of filaments with filament-derived scalation) to have occurred.
| [
"The dinosaurs were constructed out of 2 inch (5.08 centimeters) black iron pipe, with a wire mesh frame and a concrete skin. Originally they were gray in color, but by the 1950s the statues were painted bright green with white undersides. Being constructed in the 1930s, the dinosaurs reflect the thinking of the ti... |
Ants and bees have queens that are physically very different and serve very different roles than the rest of their group...how genetically different are they? | Queens are genetically identical to their sister workers. I am not entirely sure about ants but bees are fed a special substance called royal jelly which causes them to develop the way they do.
The trick is that while they are genetically identical they are *epigenetically* very different. Epigenetics strictly speaking means anything that changes an organisms phenotype (appearance, behavior etc) without changing its genotype. More recently it has come to mean chemical modifications to chromatin - the DNA/protein complex that packages the genome inside the cell. Some epigenetic modifications cause the chromatin, and therefore the genes contained therein, to be compacted and shut down, while others cause it to open up and allow for gene expression. Royal jelly contains epigenetic modulators that cause the developing queen larvae to have a different gene expression pattern from worker larvae.
The other important part of royal jelly is growth factors - small signaling proteins that encourage growth and development. During embryonic development they are produced by the organism itself, and left to their own devices bee larvae will grow into a normal bee using their own growth factors. The royal jelly is enriched for extra growth factors and allow the larvae to develop into a much larger animal.
There is a japanese scientist who published a paper in Nature about a year ago about the active components of royal jelly which effect the development of queen morphology. Its a remarkable paper partly because its just good research and partly because its a single author paper. He did it all by himself. No one does that any more. Here's the link to the paper, which you won't be able to read unless you can get journal access, but you might be able to get the gist of it if you google the author's name and look at his lab website.
_URL_0_ | [
"Queens look similar to workers, but several morphological features distinguish the two castes from each other. The queen's body is usually larger. Ocelli are highly developed, but the eyes on the queen are not enlarged. The structure of the pterothorax (the wing-bearing area of the thorax) is consistent with other... |
how do countries divide payments for sending mail by post? | They are not, as the countries themself have little to do with it (unless we are dealing with state-postal-service - but they usually are still another entity).
Lets stay within your canada- > australia example.
You buy stamps from the Canada Post Corporation. put them on your evenlope to australia and give it one way or another to Canada Post.
In case of "Canada post" - > "Australia post" both have an explicit long term contract within the [international post corporaton](_URL_0_) and Australia post keeps record of how much mail (or packages) they delilvered for Canada post. How often they demand the money i dont know.
While Australia post would not (paper)stamp your letter again, they will add their ink stamp for tracking.
How the mail gets there is differnt from contract to contract (UPS flies to the country and to the nearest/cheapest hub of the other company if they for example are not allowed to deliver letter-mail in that country, and DHL and La Poste have a joint-venture exchange point AFAIK)
Other postal companies will have diferent contract-constellations to make it work. (DHL with itself in case of Germany- > USA for example)
source: Grandfather was in Deutsche Post (which became DHL), Father was in german division of UPS | [
"In many developed countries, direct mail represents such a significant amount of the total volume of mail that special rate classes have been established. In the United States and United Kingdom, for example, there are bulk mail rates that enable marketers to send mail at rates that are substantially lower than re... |
why do cucumbers taste so mild while you're eating them, but taste so strongly when you burp afterward? | It's the cucurbitacin in them. It's a chemical that they have to help prevent certain animals from eating them (too much and there wouldn't be any to make more-hey nature!)
It's mostly in the stem end so if you don't eat that part it will cut down on it too. Also can deseed them and they will help prevent excess gas from coming up. Also the "American" slicing cucumbers have more in it and the Asian/English types have less. | [
"Depending on variety, cucumbers may have a mild melon aroma and flavor, in part resulting from unsaturated aldehydes, such as , and the \"cis\"- and \"trans\"- isomers of 2-nonenal. The slightly bitter taste of cucumber rind results from cucurbitacins.\n",
"Burpless cucumbers are sweeter and have a thinner skin ... |
how do password hashes work? | > Also, what's to stop someone from essential 'brute-forcing' hashes by starting with a and going through all the alpha-numerical symbols for 12 characters or so, and then have a just compare any given password to the compiled list of hashes?
This is called a [rainbow table](_URL_1_). And if you just did something simple like one pass of md5 to make a hash, you could easily find out what the password is from a hash just by [googling it](_URL_2_). This is why you don't just do md5 once. You would use a hashing algorithm (like md5 or better yet SHA256) hundreds of times on the same password.
You would also use random [salt](_URL_3_) and store it with the hash. A salt is not an encryption key, and having the salt won't allow you to decrypt the hash. It is just some random text you append or prepend (or both) to the original password to make the result more unique.
What the uniqueness of the salt and multiple passes of the hashing algorithm add are more time to generate all the combinations. This also prevents one rainbow table from being used for every password in your database. You would need to generate the table for each password which takes time. You want to add as much time as possible, such that the time it takes to brute force one password would take years (preferably centuries).
The number of alpha-numerical combinations of 12 length is ~3,226,266,760,000,000,000,000 ((26 + 26 + 10)^12 ). And a even rainbow table that size with just basic one pass md5 and a computer that could calculate a billion md5s a second would take a 100,000+ years to generate the whole table.
So, lets say you have a password. What you do is run it through your hashing algorithm, 1,000,000 times with a random salt appended each time. This process takes a half second to complete on your server. The user doesn't notice since the compute time isn't that long. You store the result, along with the randomly generated salt in your DB. Then the next time the user comes to log in, you take the new password they entered to check and run it though the same process. First you grab the salt from the DB though and use it as the same salt to run the 1,000,000 passes of your hash. If the resulting hash matches, the entered password is correct.
What this has accomplished is two things. First, it slows down the server side validation of a password. A person trying to brute force their way into your server by sending random passwords to be validated would have to wait a half second each time to get an answer. Second, if your database and code was compromised and someone wanted to brute force their on their own super fast machine, they would know your hashing method (1,000,000 sha256 with random salt) and resulting hash, but that would get them nothing really. They'd still need to generate all possible combinations until they matched the password. Most importantly, they'd need to through the whole table out for each password they wanted to crack. As in, if they generated all 8 length combinations to guess the first password, they couldn't use all those generated hashes for the second.
This whole process will take them a really long to even crack one 8 character length password. Lets say they're machine can do the hashing of one guess in 0.00001 seconds (50,000 times faster than your server). It would take them ~70 years for one password.
The best thing to do if you are planning to generate your own client login system is to use an already built library for generating and validating hashes. For php, there is the (poorly named) [phPass](_URL_0_).
So is it one-way then? Well, the hash is. But using a hash on a password is not really one-way. Since passwords generally have an upper bound on length (say < =12 characters for reasonable password use) it makes it such that the space that a hash is mapping probably one have any collisions. Meaning, a generated hash for a password probably won't match another different password (i.e. the hash is unique to the password). But hashing algorithms aren't specifically designed for use in password encoding.
They are generally designed for checking data integrity and can take any length string. md5 for example can take a whole harddrive (say 1TB in size) and spit out a 32 length hexadecimal string. It can take an infinite length string and boil it down to a 32 length hexadecimal string. In that scenario, you couldn't take the md5 hash and run through some magic and get the harddrive image. There are millions of strings that would match that hash that are less then a TB is size. So in that sense, the hashing algorithm is "one-way".
| [
"Hash functions can be used to verify digital signatures, so that when signing documents via the Internet, the signature is applied to one particular individual. Much like a hand-written signature, these signatures are verified by assigning their exact hash code to a person. Furthermore, hashing is applied to passw... |
In WWII were there any reports of either military or civilian injuries or deaths caused by anti-aircraft weaponry, or any type of air based weaponry, missing a target and falling back to the ground? | hi! there's always room for more input on this, but you'll be interested in several previous posts on the impacts of anti-aircraft weapons and dogfights...
Anti-aircraft
* [What happened to all the stray bullets fired in the skies during WWII? (Or any war for that matter)](_URL_4_) - featuring /u/defrost
* [Are there any statistics regarding WW2 flak as a source of friendly fire (civilian or otherwise)?](_URL_0_) - featuring /u/astrogator
* [How dangerous was WW2 anti-aircraft Fire to people on the ground below it.](_URL_1_) - featuring /u/the_alaskan (post also links back to the above post)
* [Did any shell fragments from flak cannon defense ever cause injury or damage for people on the ground?](_URL_5_) - featuring /u/when_ducks_attack
* [Did anti-aircraft guns cause more damage to the city they were trying to protect?](_URL_3_)
dogfights
* [I imagine dogfighting between two planes would create a huge ammount of stray bullets travelling a good distance. Are there recorded cases of civilians or soldiers dying because of them?](_URL_2_) - contains links to several more posts
Most/all of these posts are locked now, so if you have follow-up questions, ask them here & post the relevant user by including their username | [
"There were other casualties after the war, mostly due to land mines. During the war, the alliance reported the loss of the first US stealth aeroplane (an F-117 Nighthawk) ever shot down by enemy fire. Furthermore, an F-16 fighter was lost near Šabac and 32 unmanned aerial vehicles (UAVs) from different nations wer... |
airport economics | Couple things:
- Retail space. Airports generate a ton of money from retail. Renting space to specific stores/shops, selling products directly, etc. I would not be shocked to learn that franchise set ups inside airports are also owned by the airport directly (like burger king and mcdonalds)
- Flowage fees for fuel placed into the aircraft
- Usage fees from airlines for access to gates, the number of passengers they move through the airport, usage of terminals, etc.
- Land leases to places like rental car companies and retail space outside of the airport but may still be on airport property
- Landing fees
They can also generate revenue through federal funding to infrastructure and such.
| [
"The airport city model considers the idea that an airport can do more than perform its traditional aeronautical services, evolving new non-aeronautical commercial facilities, services and revenue streams. Airports are now routinely targeting non-aeronautical revenue streams amounting to 40–60% of their total reven... |
the falcon9 landing. why is it cool? what does it get us closer to doing? | As you can probably imagine, one of the most expensive aspects of space travel is building a rocket to get there. SpaceX has been working to make re-usable rocket technology at an unprecedented scale, and the Falcon 9 landing tests are part of that goal.
If SpaceX are able to land their rocket boosters for safe retrieval, they can save a *lot* of money and resources.
We can already get to space. This would mainly make it easier and cheaper to do so, which might open up other opportunities that otherwise wouldn't be feasible. | [
"BULLET::::- SpaceX successfully lands the first stage of its Falcon 9 rocket on a platform at sea, the fourth time it has made such a landing. The landing, made aboard a platform in the Atlantic Ocean off the coast of Florida after launching a communications satellite into orbit, is particularly challenging becaus... |
why do some noises produce a physical reaction in people? | Well, your body reacts to sounds by using your brain to resurface earlier instincts. For example, sudden high pitched sounds (such as writing on a chalkboard) will make you feel stressful and "wriggly" because your primal brain tells you to run from the nonexistent predator or natural danger that is suddenly screeching near or at you. Interesting fact- us humans are so horrible, that clanging, metallic sounds resemble war, and can cause legitimate, unexplainable (by them) fear in some people. | [
"For example, those who suffer from misophonia often report that specific human sounds, including those made by eating, breathing, whispering, or repetitive tapping noises, can precipitate feelings of anger and disgust, in the absence of any previously learned associations that might otherwise explain those reactio... |
how does putting food in hot oil fry it (like, how does the actual frying process happen)? also, what are those bubbles, is it water that leaves the food due to the high temperature or something else? | Oil is active as a heat stabilizer and heat transfer fluid. As the oil heats various components begin to break down or evaporate (boiling does this rapidly). This takes energy and holds the temperature relatively even as the oil evaporates or smokes. This means that your food is cooked at a relatively stable high temperature evenly across the entire surface, which is what gives it the "fried" consistency (coupled with the residual oil).
The bubbles are steam. Usually. | [
"If performed properly, deep-frying does not make food excessively greasy, because the moisture in the food repels the oil. The hot oil heats the water within the food, steaming it from the inside out; oil cannot go against the direction of this powerful flow because (due to its high temperature) the water vapor pu... |
Was lacrosse really used to settle national disputes? Are there other examples of sports settling national disputes? | There are a lot of lacrosse-related metaphors regarding warfare, and warfare-related metaphors regarding lacrosse. Many of the preparations undertaken by ball players have close or identical analogues among wartime preparations. The association between the two has deep roots and grew increasingly stronger in the late-1700s and early 1800s. At that time, actual warfare became less common in the Eastern Woodlands and men required a new venue for acquiring prestige formerly associated with military service.
This relatively recent shift in metaphoric emphasis has obscured other aspects of the game. At the time of Contact and for quite some time after, it was employed as a medicine game. More importantly for your question, though, a game between two villages was a huge social event and the subject of considerable gambling, with all manner of prizes up for grabs. Though the sum total of exchanges could be staggering, they usual involved many small personal wagers. However, the leaders of villages or nations might wager for higher stakes on behalf of their constituents.
A famous example of this is recorded in Horatio Cushman's [History of the Choctaw, Chickasaw and Natchez Indians](_URL_1_). The incident was related to Cushman from the well-respected Creek-by-birth, Choctaw-by-adoption elder Stonie Hadjo, through an intermediary and concerns an 18th Century disagreement between the Creeks and the Choctaw over a particularly lucrative hunting ground. The Creeks claimed it because they had been the ones to discover that a large population of beavers had established themselves in the area, while the Choctaw claimed it because it was within their general territorial claim. To settle the dispute, a ballgame was held. Thousands of people of each nation gathered to observe the game.
The Creeks won the game, but during the celebration, a Choctaw player and a Creek player exchanged insults which escalated into a brawl and into an all out fight that lasted the rest of the evening and picked up briefly the following morning. The leaders of the respective sides got a hold of the situation and quickly entered into peace negotiations. They matter was laid to rest then, and the Choctaw granted ownership of the disputed lands (which turned out not to be as lucrative as everyone thought anyhow). Hadjo regarded the post-game fight as worse than any actual war fought between the Choctaw and the Creek before; five-hundred people allegedly died during the fighting, the majority of whom Hadjo considered to be the most promising young men of their generation. They were buried near the ball field while the peace talks were on-going, and in 1832 their graves were looted for the silver that had been buried with them.
For more information about lacrosse, its social context, and some other famous lacrosse games, see [American Indian Lacrosse](_URL_0_) by Thomas Vennum. | [
"Lacrosse traditionally had many different purposes. Some games were played to settle inter-tribal disputes. This function was essential to keeping the Six Nations of the Iroquois together. Lacrosse was also played to toughen young warriors for combat, for recreation, as part of festivals, and for the bets involved... |
Why do we only look for radio waves in SETI research? | We assume that life is like us, because we have to. We're aware that life could take any form we can or can't imagine, but we don't know how to look for life we can't imagine, and while we might be able to look for life we can imagine but is very different from us, it's smarter to look for life like us. Why? Because we know that life like us is possible and has appeared at least once in the universe. We have no evidence that any other kind of life is possible or present. We're looking for what is the most likely, given the data available to us.
| [
"BULLET::::- Cognitive radio techniques: each radio measures the spectrum in use and communicates that information to other cooperating radios, so that transmitters can avoid mutual interference by selecting unused frequencies. Alternatively, each radio connects to a geolocation database to obtain information about... |
How did the Mexica (aka Aztecs) deal with the umbilical cord after birth? Was there any cultural significance attached to it or was it merely disposed of? | Aztec births were a highly ritualized affair involving spirituality and midwifery. When the umbilical cord was removed it was preserved and when a son reached adulthood he would bring his to a battle field and bury it. A daughter would bury hers next to the family's hearth. There is an illustrated book called the Florentine Codex, I believe, that describes most (if not all) practices in regards to birth and raising children.
[Edited for link] (_URL_0_) | [
"In placental mammals, the umbilical cord (also called the navel string, birth cord or funiculus umbilicalis) is a conduit between the developing embryo or fetus and the placenta. During prenatal development, the umbilical cord is physiologically and genetically part of the fetus and (in humans) normally contains t... |
Interested in the Three Kingdoms | I would suggest you read (assuming your an English speaker) the book itself! There are many translations available, the one I read was the translation by [Robert Moss](_URL_0_). Also there is the actual historical text that the novel was based on, Records of the Three Kingdoms by Chen Shou, for that I would recommend checking out any university libraries in your area.
And also I'll ping /u/cthulhushrugged for a better answer. | [
"The Legend of Three Kingdoms () is a video game series originally developed by OdinSoft, later by UserJoy Technology. The series includes seven PC-based single-player titles and three online and one mobile titles, which haven been released in China, Japan, South Korea, Russia, the United States, and South Asia. It... |
What were preparations like in the dsys/hours/minutes before an attack on a castle or city back in medieval times? | It's useful, I think, to first differentiate fortifications into three basic types. These are the fortified town, the baronial castle, and the ducal/royal castle. The three really only have in common the fact that they are fortified places of strategic importance; the way in which they are constructed, manned, and function in peace and war differ dramatically. I want to make this very clear: everything I speak about below applies to 11th-13th century England and France, and should not be taken as definitive in regards to any other area or period.
The fortified town is just that - a town which has been reinforced with walls of some variety. These could be permanent fortifications, ranging from masonry walls reinforced with towers and gatehouses at the high end of the scale, to simple timber palisades at the low end. The penultimate fortified town of medieval Europe was probably Constantintople, which was defended by some twelve miles of walls, four on the land face, and eight on the sea face. Some had no permanent walls, but in times of crisis were hurriedly encircled with jury-rigged ramparts of earth, timber, and stone, sometimes in as little as two weeks. Regardless of their scale and sophistication, fortified towns suffered from the same problem: they were not purpose-built military installations, but population centers around which defenses had been thrown up. Generally, this meant a weaker geographical position, many entrances which must be defended, and a long circuit of walls. The longer the stretch of walls, the more men are needed to defend them. Though it may seem counter-intuitive, a city with a garrison of 500 men may well be weaker than a castle with 50, because those 500 are less concentrated. A small or unimportant town might be forced to rely wholly on a local militia of artisans and merchants; a more important city, like Rouen or Paris or Poitiers, might have the benefit of a permanent royal, ducal, or comital garrison.
The second fortification we will talk about is the baronial castle, though that term is unfortunately imprecise. These are fortifications of local, rather than regional, importance, belonging to mid-level aristocrats referred to variously as castellans, barons, vavasours, and lords; the regionally, but not nationally powerful men. The majority of castles were of this type, and they could be very numerous, with eight, ten, or more in a given county or shire, spaced every few miles, this being the area which a small mounted garrison could exert control over. This is a dedicated military fortification, generally sited on a site of strong natural strength - most commonly, a ridge, hill, or man-made mound called a motte. It varied with time and military technology, but could range from a simple wooden hall surrounded by one or more timber palisades, to a stone keep (a very large tower) surrounded by palisades or stone curtain walls, to, in the most lavish cases, a series of two or three interconnected stone courtyards, with towers and gatehouses. But it was also an aristocrat's court, where a lord and his household of knights and servants lived (though it was not uncommon for a magnate to have two or even three such castles, in which case those not resided in would be more purely military structures). In event of siege, it would be defended by the aforementioned household, supplemented by landed knights owing service to the lord and the free peasants of the nearby area. These castles, owing to their small size, inadequate garrisons, and lack of stockpiled provisions, tended to fall very quickly to determined besiegers.
The third variety is the royal or ducal castle. This is more what people think of when the term castle is mentioned. Besides being generally larger and more modern than the typical baronial castle, it is a fort, not a home, and almost always defended by a permanent, often quite large, garrison under a commander appointed by and answerable to the king or duke. It was very frequently constructed at great expense and with great care, almost always to defend a strategic point, such as a river crossing, an imposing height, or a threatened frontier. Thus we can say that these castles, rather than being locally important, were very often regionally important; their possession or loss determined the possession or loss of the wider region. With the funds of the crown to back them, these generally were kept very prepared for siege, with huge stocks of food; Chateau Gaillard survived 7 months of siege before being forced to surrender, not by lack of food, but by the compromising of its last remaining defensive wall.
The immediate defensive measures were quite similar among them all. Get in as much food and drink as possible; reinforce any weaknesses in the walls, often with wooden hoardings; get every able-bodied freeman available under arms. Then get ready to wait for as long as it takes a relieving army to arrive, the food to run out, or the defenses to be breached and surrender compelled. | [
"The most common practice of siege warfare was to lay siege and just wait for the surrender of the enemies inside or, quite commonly, to coerce someone inside to betray the fortification. During the medieval period, negotiations would frequently take place during the early part of the siege. An attacker – aware of ... |
How did Rome get buried? | I didn't know /r/askhistorians did guides (I'd definitely hire some of the mods for private tours!)
It's definitely not a stupid question, how indeed does a city fall to ruin and get buried under the ground when people still occupy it?
This isn't exactly asnwering about Rome but /u/Pachacamac answers why ruins happen and get buried in cities with people living nearby.
_URL_1_
/u/gpodolec answers more specifically why rome gradually went to ruin
_URL_0_ | [
"The Etruscans, who at the time occupied what is now Rome, had placed their dead in early dug-outs, such as the Tomb of the Capitals, and less complex tumuli. The early Roman custom had been cremation, in which burnt remains are placed in a pot, urn, or ash-chest, and then often kept in a columbarium. Around the 2n... |
what does it mean when a drug (cocaine, heroin) is cut? | It means it's been cut *with* something in order to stretch the supply. Kind of like if you have half a can of soda, and you fill it up with water. You now have a full can, but it's much weaker soda. And if you sell it like that, whoever bought it might be pissed.
With drugs, it's not unusual to have them cut with something that's even *less* healthy than the drugs. | [
"Heroin, also known as diamorphine among other names, is an opioid most commonly used as a recreational drug for its euphoric effects. It is used medically in several countries to relieve pain or in opioid replacement therapy. It is typically injected, usually into a vein, but it can also be smoked, snorted, or inh... |
Do castrated people lose their libido? | Yes. Your testicles are a driving force in testosterone production, which is key to having any sort of sex drive for males. Steroid users often use faux testosterone to get bigger, causing their body to stop making its own. So when they get off a cycle the have to block estrogen production and wait for natural testosterone to return. And hope they're T levels are in check with their estrogen levels. Thus normal libido.
| [
"Castrations after the onset of puberty will typically reduce the sex drive somewhat or even eliminate it altogether. Castrated people are automatically sterile, because the testes (for males) and ovaries (for females) produce sex cells needed for sexual reproduction. Once removed, the subject is infertile. The voi... |
When will earth lose the moon? | We will not lose the Moon. It will recede as it exchanges energy with the Earth by slowing our rotation. Eventually the recession will stop when the Earth becomes tidally locked to the Moon and one side of the Earth will always face the Moon.
The opposite process has already happened and the same side of the Moon faces the Earth. When this happens to the Earth, one day will take several "now" months, that is how slow we will rotate. This process is very slow due to our greater mass, the Sun will be long dead before this happens. | [
"Currently, the Moon is moving away from Earth at a rate of 4 cm (1.5 inches) per year. In 50 billion years, if the Earth and Moon are not engulfed by the Sun, they will become tidelocked into a larger, stable orbit, with each showing only one face to the other. Thereafter, the tidal action of the Sun will extract ... |
why do so many older people who are otherwise competent struggle to use computer technology (such as copying and pasting or attaching a file to an email)? | Biggest obstacle is they tend to use the computer very rarely. It's just not part of their mindset. They get news and entertainment from the television. Communication is through telephone, postal mail, or a walk down the street.
This lack of skill makes them nervous about breaking it. They grew up with announcements all the time about how your car, dryer, hot water heater, and the like could break down or even kill you if they weren't used and cared for properly. Elderly people also tend to be embarrassed/ashamed about their lack of skill so avoid facing that as much as possible.
If you happen to be in the position of helping an elderly relative in using their PC here are some tricks I've learned:
* DO NOT TOUCH THE MOUSE OR KEYBOARD. Tell them how to do something, and only take control if they ask you to. It's **very** tempting to just do it yourself to speed things along, but they learn better if they actually do it themselves rather than just hear it.
* Remind them (and yourself) that they're not incompetent, ignorant, a failure, whatever just because they don't know how to use a computer. They've accomplished a lot in their lifetime, and lots of people are uncomfortable with computers.
* Reassure them that it's very hard to break a computer, and (usually) very easy to fix one.
* let them move at their own pace
* finally, don't touch the controls. Even if an error message or something comes up. They need to have the confidence that they can handle little hiccups like that.
| [
"Because many of the people in the older generation are less likely to have skills on the computer, their technological inabilities also hold them back from being hired. As the years have passed, many companies have begun to focus on using the internet and other programs on the computer, making it more likely they ... |
why do companies doing an ipo need to "secure $x billion from y investors" and need z investment companies to "sponsor" them? | They are sponsors in that they have committed to pay at least some amount of money to buy shares of the company. If there was no secured funding, the private owners of the company might have no bidders at all. The secured funding also sets a floor on the price so that they don't get unlucky and sell the whole company for peanuts.
In addition, there are many rules in place for IPOs so that ordinary investors don't get defrauded by the current owners of the company or other bidders. If they weren't in place, the first bidders might pay 1 cent per share while everyone else paid much more. | [
"Due to the current economic climate, IPOs have become a rarer occurrence recently, causing venture capital firms to look towards mergers and acquisitions. This is a more realistic scenario, especially when startup companies do not look to function independently. Acquisition financing uses investment funds to acqui... |
why do some electronics not turn on while charging? | Simply put, those things don't have a circuit that diverts power to the device as well as the battery.
Batteries can't charge and discharge at the same time. When you plug something like your phone in, it has a circuit which directs the required power to the phone and the rest to the battery to charge. Some devices are simpler and the power can only go to the battery. | [
"Due to the electromagnet in the contactor, if power to the machine should fail the contactor will automatically disengage. Unlike machines with an ordinary latching switch (such as a common light switch), when the power is resumed the machine will not operate until being turned on again. As a result, magnetic star... |
Why do things like glue, sticky notes and other adhesives like that become "unsticky" when it's cold? | Most glues conform to the shape of whatever they are bonding to. If there are microscopic ridges on a surface the glue would fill them This increases surface area for chemical bonding and attraction which is the primary way the glue sticks.
When its cold the glue can contract and it may not conform to the surface anymore if it contracts at a different rate than the material its bonded to. Also the glue will harden and may not be able yield when the material its bonded to puts a stress on it or vice versa. | [
"The adhesive is largely affected by the temperature as polymeric adhesives are commonly used today. Polymeric materials used today are viscoelastic materials, which enables easy application and quick adherence to the substrate. Adhesive degradation in the bulk is largely due to temperature effects, which reduce ad... |
why are sodas made with such strong acids? | As far as I understand it, the do it to equalize the sweet taste of sugar. Now, you asked why they even add as much sugar in the first place.. sugar sells. Your body reacts to sugar well comparable to how it reacts to heroin, although significantly less drastic. You have the feeling of happiness and being energized. If they didnt add that sugar, coke would sell a lot less. If your body notices a lack of sugar or wants more of the energy/happiness, it usually forces you to drink coke or eat something sweet.
Compare it to salt/umami tastes in chips. The umami is really beneficial for your body, it would normally carry lots of nutritients and minerals. The bad thing is, that umami in chips is usually just the pure taste without the extracts that you would have in natural umami taste.
Well I drifted off-topic here, but in general, sugar makes you lets you more likely grab a coke than water/another soda, acid is used to equalize the sweetness. | [
"Caustic soda is limited to smaller combustion units because it is more expensive than lime, but it has the advantage that it forms a solution rather than a slurry. This makes it easier to operate. It produces a \"spent caustic\" solution of sodium sulfite/bisulfite (depending on the pH), or sodium sulfate that mus... |
Besides Allied interception of Japanese plans throughout the Pacific theatre, what caused the demise of the Imperial Japanese Navy and its forces? | Allied codebreaking and other SIGINT ultimately had relatively minor impact compared to the sheer quantitative, qualitative, and technological advantages that the US Navy had over the Japanese one.
The authors of Shattered Sword have a [certain webpage](_URL_0_) in reference to just how massive the Allied advantage was in the Pacific. Simply put, by 1945, the US would have been able to deploy something along the lines of 30 modern CVs, 9 modern CVLs, and over 120 CVEs, against 14 Japanese CVs (of which 1 was arguably even close to the quality level of the US ones), resulting in anywhere from a 2.5 to 3 to 1 disparity in aircraft capability. In addition, the US aircraft were far superior to anything the Japanese could put into the air, and the US could replace their plane and pilot losses, which Japan simply could not due to a combination of poor logistics and a strict naval aviation training regime that made pilot training extremely difficult.
That was just carriers. The US Navy was larger than the rest of the worlds navies, combined. And the US models were the best in the world. In the Battle off Samar, 7 destroyers and a handful of escort carriers, which didn't even have torpedoes for their aircraft, bloodily repulsed a sortie by the main battleline of the Japanese navy, including almost all of their battleships and remaining heavy cruisers.
I talk more about this [here](_URL_2_), [here](_URL_1_), [here](_URL_3_) and [here](_URL_4_). | [
"By 1944, the German Navy no longer presented a major threat and the Royal Navy was able to transfer major units to the Far East. This would fulfil a British wish to become involved in the Pacific War. First, however, experience was required of large-scale naval air operations and of United States procedures. To th... |
how does one secure venture capital funding? | Hype might not be the right word- but there is a significant preference to high-growth companies (usually young ones, since the maturity phase is relatively unlikely to lead to a high (risky) ROI-1). A mere business plan is usually not good enough unless you've discovered an untapped market or |the market is monopolistic * (low barriers to entry-2, basically). Competition often makes it too unpredictable for funders to just accept a business plan- initial results are greatly valued. After that, get someone with connection or approach companies yourself (your business career is truly aided by years of solid networking)- have a good presentation where you not only show some passion / strategy, but also give them some cold hard numbers and be the prize. (their initial offer will usually be near the minimum of what they're willing to give)
Furthermore I suppose it's probably also important whether you want to give them equity (stock) or just have them be a glorified bank (debt).
-1ROI = Return on investment, e.g. if they're going to invest 25.000, and their analysts say you've got only a 50% survival rate and no real assets to lay claim on if you do perish, they're going to want a lot more than a 25.000 return.
-2barriers to entry = how easy it is for a new player to enter a market, compare a farmer's market (near perfect-competition, easy as shit) to e.g. the PC market (oligopoly, hard as shit). The uncertanties of competition will be very dominant in oligopolies.
It's a little late, so I might've been a bit incoherent, but these are some of the basics.
*edit: Perfect competition, not monopoly. Dayum. Edit #2 Why the fuck would a venture capitalist fund a business in perfect competition? This is stupid, I apologise. (Made this post at like 04:00, wasn't thinking too straight.) | [
"Venture capital (VC) is a type of private equity, a form of financing that is provided by firms or funds to small, early-stage, emerging firms that are deemed to have high growth potential, or which have demonstrated high growth (in terms of number of employees, annual revenue, or both). Venture capital firms or f... |
how can companies like amazon afford to price things at such low margins? | Amazon's margin is ~15%, it's not low. Really what you're seeing is that many manufacturers place their MSRP high enough that the moderate traffic mom and pop shop in a major city can sell it at MSRP and still make rent, and they can afford to mark it down for various sales. [Thus most industries have 30-40% gross profit margins](_URL_0_).
Amazon however has worked out awesome shipping rates (due to volume), and has no sales people, and always operates from warehouses, usually located in the sketchy part of town, not main st. Their costs are much lower than most stores, and instead of marking things down on sales, they really just take the actual cost, add their ~15%, and sell it as is, which for many industries is a very large percent off MSRP. | [
"Businesses that want to price competitively will monitor their competitors’ prices and adjust accordingly. Amazon is a market leader in retail that changes prices often, which encourages other retailers to alter their prices to stay competitive. Competitor-based dynamic pricing can increase sales, especially if th... |
why can't we use waste gas to create more energy? | The 'gas' emitted from power stations is the bi product of combustion of their fuel, which could be gas, coal, whatever. A hefty amount of that is water vapour.
For a gas to be able to turn a turbine then it has to be expelled under pressure, which is of course how power stations work, usually by steam turbines. But the emissions from the plants are not usually under any significant pressure, not enough to turn a turbine anyway, so to attempt to put a turbine on the top of the chimneys would be pointless. | [
"Using waste as fuel can offer important environmental benefits. It can provide a safe and cost-effective option for wastes that would normally have to be dealt with through disposal. It can help reduce carbon dioxide emissions by diverting energy use from fossil fuels, while also generating energy and using waste ... |
why are smartphones vertically oriented screens by default and design, yet all other forms of screens and displays are all designed horizontal? | Have you ever tried holding your phone horizontally with one hand to use it? | [
"Because of the building-block nature of the system, the configuration of the overall screen area and shape is flexible, leading to simple traditional rectangular displays, and more complex non-standard shapes.\n",
"To promote consistency between device classes, Android tablets now use an expanded version of the ... |
Do Religious Scholars Take the Gospel of Judas Seriously? | The Gospel of Judas gets a good deal of action in academic circles devoted to the study of ancient Christianity, as /u/anoldhope mentions. (Take a look around [JSTOR](_URL_2_) or [Google Scholar](_URL_3_), for instance.) In fact, it gets just as much scholarly attention as any of the many [other ancient, non-canonical gospels](_URL_6_).
As for GosJudas' lack of "impact" in modern religious practice, that depends on several factors. (**N.B.:** I am a Christianity scholar, so I will limit my discussion to modern Christianity.)
In Christianity, the focus has historically been placed on the canonical New Testament, and any books outside that canon were treated with scorn and condemnation.
Many modern Christians (specifically those from conservative traditions) maintain the same scorn towards these other Christian texts. Other modern Christians (usually, those who are more progressive) do not actually feel any animosity towards ancient, non-canonical Christian literature, but still neglect it, because of the longstanding focus on the canonical NT. Finally, a somewhat smaller portion of modern Christianity actively embraces non-canonical literature (as exemplified by the *[New New Testament](_URL_1_)*.)
**Further reading:**
-On the varieties of ancient Christianity, see Bart Ehrman's books *[Lost Christianities](_URL_0_)* and *[Lost Scriptures](_URL_5_)*.
-For a conservative Christian reaction to the Gospel of Judas, which typifies the tradition's views on non-canonical gospels in general, see Albert Mohler's blog post, ["From Traitor to Hero? Responding to 'The Gospel of Judas.'"](_URL_4_)
EDIT: Fixed a typo. | [
"The Gospel of Judas is another controversial and ancient text that purports to tell the story of the gospel from the perspective of Judas, the disciple who is usually said to have betrayed Jesus. It paints an unusual picture of the relationship between Jesus and Judas, in that it appears to interpret Judas's act n... |
the difference between pressure and compression? | > As I understand it fluid can't be compressed
And that is where you went wrong, any fluid can be compressed. Any material at all can be compressed of course.
Fluids are often said to be incompressible because they take a lot of force to compress even a little bit, but it is a simplification which isn't strictly accurate. Many engineers new and old take such simplifications to heart and don't understand which are approximations to make calculations easier under normal conditions. | [
"In mechanics, compression is the application of balanced inward (\"pushing\") forces to different points on a material or structure, that is, forces with no net sum or torque directed so as to reduce its size in one or more directions. It is contrasted with tension or traction, the application of balanced outward ... |
Did ancient people really get captured by marauding bands of slavers? | Yes, certainly. If you want a good real-life version of the Gladiator scene we have Julius Caesar's capture by pirates. These pirates would capture people and sell them as slaves, often to rich Romans.
However, if they happened to catch an important person, such as Caesar, they ransomed them instead of forcing them to work as some agricultural slave (or being forced to fight in the arena!). These important captives were much more valuable being ransomed than simply being sold as a slave. Poor people had no such luck.
[Here](_URL_0_) you can read Plutarch's version of the incident. | [
"Africans were captured in wars, as retribution for crimes committed or by abduction and marched to the coast in \"coffles\" with their necks yoked to each other. The most common means of enslaving an African was through abduction. They were placed in trading posts or forts to await the horrifying six- to twelve-we... |
how do other countries come to know if a nation has conducted a missile test? | In the case of North Korea, the US probably has a satellite pointed at the country 24/7 to detect missile launches. Maybe some other detection equipment based in Japan and South Korea too | [
"The purpose of the first tests was to determine the feasibility of dropping the 10Kh missile from an aircraft in flight and ignite the pulse jet about below the mother-ship, but only six out of 22 missiles did so correctly. The second, more successful series of tests, achieved a success rate of 12 out of the 22 la... |
Are there any examples of positive cooperation between the Soviet Union and the USA during the Cold War? | There was the Apollo-Soyuz Test Project that led to a joint US-Soviet space mission in 1975. ASTP's value in terms of scientific or engineering progress was extremely questionable, but it certainly qualifies as a "positive, cooperative moment." One could argue that that first instance of working with the Russians in space helped lay the groundwork for the International Space Station. | [
"During the Cold War (1947–1991), when the Soviet Union and the United States were engaged in an arms race, the Soviet Union promoted its foreign policy through the World Peace Council and other front organizations. Some writers have claimed that it also influenced non-aligned peace groups in the West, although the... |
Is it known who shot down the plane that triggered the Rwandan genocide? | I asked a similar question a week ago! If I may ask a follow up question, why was it that so much of the world almost seemingly refused to get involved and even turned blind eye to the Rwandan Genocide?
Why did countries like the U.S. And Europe and even local surrounding countries abstain from trying to stop the violence occurring? | [
"A 2006 French inquiry with the International Criminal Tribunal for Rwanda accused Nyamwasa, Kagame and four other officials of organizing the shooting down the plane of then Rwandan president Juvénal Habyarimana. The event is cited as the catalyst for the Rwandan genocide. Nyamwasa has also been accused by Spain o... |
What were ancient Roman parties like? Describe the most opulent/crazy one. | You should read the feast of Trimalchio. It's not about orgies and is more satire and mocking of the extravagance of Roman elites.
In this case it is mocking the faux sophistication of Trimalchio (a former slave who has now become quite wealthy) as he hosts a dinner party but repeatedly commits mistakes which actual educated cultured Romans would notice but of which Trimalchio is oblivious of.
| [
"The youth of Rome had several forms of athletic play and exercise, such as jumping, wrestling, boxing, and racing. In the countryside, pastimes for the wealthy also included fishing and hunting. The Romans also had several forms of ball playing, including one resembling handball. Dice games, board games, and gambl... |
how do thermal optics pick up heat signatures from such large distances away? | if i understand this correctly, its basically just shifting the infra red spectrum so it can be seen. (electronically, with a sensor and a screen)
_URL_0_
its always there, we just are not equipped to see it.
life would be weird if we could see somewhere up to fm frequencies.
_URL_1_
suprisingly eli 5 | [
"The brightness of the image produced by a thermal imager depends on the objects emissivity and temperature. Every material has an infrared signature that aids the identification of the object. These signatures are less pronounced in hyperspectral systems, which work similarly to multispectral but use more bands, ... |
What were the attitudes of Orthodox Russian rulers towards the Crusades and the Crusaders? | As a follow-up, how Christianized was late 11th century Russia? Was Orthodox Christianity the religion of the majority of people west of the Urals? | [
"The Teutonic Order's failed attempts to conquer Orthodox Russia (particularly the Republics of Pskov and Novgorod), an enterprise endorsed by Pope Gregory IX, can also be considered as a part of the Northern Crusades. One of the major blows for the idea of the conquest of Russia was the Battle of the Ice in 1242. ... |
why do i feel depressed at random times for no reason? | You have no history under this name. Are you male, female, have a family history of depression, etc? I don't think any one can say much about you specifically without more info. That and you should see a doctor as "medical"advice really shouldn't be given on redit. | [
"Nearly every day, the person may be indecisive or have trouble thinking or concentrating. These issues cause significant difficulty in functioning for those involved in intellectually demanding activities, such as school and work, especially in difficult fields. Depressed people often describe a slowing of thought... |
why u.s. conservatives are so against abortion but generally the first to gripe about families with multiple children on welfare. | Because they are honoring a set of principles:
1. the fetus deserves protection as a living thing.
2. it's not fair to others to create economic advantage for some without the hard work put in by the rest of us.
You too have principles that result in "tension" - where upholding one leads to pushing against another. For example, I believe as an entrepreneur that I ought to be able to create a company like I want to and hire people that I want to hire and pay them what I want to. I also believe we need to have an organized system of immigration - these things are total odds. I also believe that we need to protect rights of those who have been historically screwed and that I shouldn't be allowed to only hire white men like myself beyond some point. Tension. Part of political life.
You're asking of those you disagree with to meet a bar of consistency based entirely on your framing of the issues. These are independent considerations based on primary principles to one audience, and thinking of it as "stupidity" doesn't further our ability to find common ground.
| [
"The Christian right opposes abortion, believing that life begins at conception and that abortion is murder. Therefore, those in the movement have worked toward the overturning of \"Roe v. Wade\", and have also supported incremental steps to make abortion less available. Such efforts include bans on late-term abort... |
why do certain bugs and glitches appear on seemingly random occations in some programs? | The dont appear at random, but after a series of events / when the game is brought inr a certain state that triggers the bug.
Games and programs are made so complex these days, that its nearly impossible to test each and every permutation / state the game can be in | [
"Errors in computer programs are called \"bugs\". They may be benign and not affect the usefulness of the program, or have only subtle effects. But in some cases, they may cause the program or the entire system to \"hang\", becoming unresponsive to input such as mouse clicks or keystrokes, to completely fail, or to... |
Was the Isthar gate and it's surrounding walls ever used in defence under a siege? | It depends on which Isthar gate you mean. Babylon had eight main gates, that were named after the closest temple to that gate. Babylon also fell to the Kassite and Assyrians after the time of Hammurabi, but before the rise of the Neo-Babylonian Empire. These attacks on Babylon are not well documented so it is uncertain if these attacks focused on the Isthar gate or not. However, it is the most likely axis of advance for an Assyrian army that was attacing Babylon.
The Isthar gate that most people remember is the glazed brick Isthar gate that Robert Koldway excavated in the early 20th century. The glazed bricks from the lowest courses were well preserved and formed the basis for the rebuilt Isthar gate in the Pergamon Museum in Berlin. That gate was built during the reign of Nebuchadrezzar, circa 600 BC. That gate was at the northern end of the Processional Way inside Babylon. Nebuchadrezzar also had a large fortress built around the north side (outside) of that gate. So the artistacly famous Isthar gate was no longer part of the outer wall of Babylon. Also, when Nabonidus was the ruler of the Neo-Babylonian empire, he was less powerful than Nebuchadrezzer. Nabonidus' religious reforms were not that popular, the Persian king Cyrus was able to undermine Nabonidus' authority with a long term and successful propaganda campaign, and in 539 BC, when the Persians overran Babylon, they did so without a major fight. The Babylonians greeted Cyrus as a liberator, at least in the Persian sources on the fall of Babylon. So, the Isthar Gate at the Pergamon museum almost certainly did not withstand a siege.
Source: John Oates "Babylon" | [
"These are gates in the walls of the Upper City of the Belgrade Fortress. Gates that are connected to each other are not exactly aligned. This was done to prevent use of siege engines on the inner gate, if the outer gate would be breached.\n",
"The fortifications remained in active use until the 1850s, when the g... |
why is a drone strike considered invariably worse than an f-16 pilot dropping a 500lb jdam? | When the crossbow was first invented, it allowed a grubby peasant to kill a noble knight. For a while people, mostly those who relied on knights, labeled crossbows as "dishonorable", and try to discourage their use. Eventually, warfare adapted and moved on.
That is kind of where we are with drones. People are more comfortable with a standard air strike, because a pilot is at risk and there is some sense of "fairness". But because drones are new and spooky, complaints against them get more airtime. | [
"With an elevation angle of up to 60 degrees and 12 propellant loads to choose from, the B-4 virtually met all the expectations it was given, capable of crushing its targets via an optimal projectile trajectory.\n",
"This weapon enabled the German pilots to attack their bomber targets from a safer distance of ove... |
What is the Banach-Tarski paradox? | Of course there exists a bijective function from the set of one sphere to the set of two spheres. That is, we can break up a sphere into uncountably many points, and rearrange the points into two sphere. So we're essentially forgetting everything about the first sphere, except how many points it has, and then artificially creating two new spheres because these have the same number of points. That's not super interesting. You can take a line segment and stretch it to get a line segment with double the length. While we're not breaking the line down into it's base points, we are distorting and skewing it. So that's not super interesting either. Both of these kinds of operations allow us to create volume, so it's not surprising when we get larger volumes.
Banach-Tarski says that you can take a sphere, cut it up into five pieces, then using only rotations and translations (ie without stretching or skewing any of the pieces) we can put them back together in such a way that results in two spheres identical to the first in every way, doubling the volume. All of the geometry is preserved, yet we double what we started with. None of the operations that we use allow us to create new volume, we're just rotating and translating these pieces, yet we do create new volume. This *is* interesting.
It's a paradox because it *shouldn't* happen. It's even a surprise to people who know all the exact mathematical definitions. Rotations and translations do absolutely nothing to volume, yet Banach-Tarski proves that we can use rotations and translations to double volume. There's something nontrivial and paradoxical going on.
The issue is the existence of "[Non-Measureable Sets](_URL_0_)". These are sets that do not have a volume. Their volume isn't zero, they have no volume in the sense it doesn't even make sense to *talk* about their volume. They break the idea of "volume". We cannot write these sets out or construct them in any meaningful way, their existence is just guaranteed by of the [Axiom of Choice](_URL_1_). It should be noted that the existence of these kinds of sets is not a trivial result.
What is happening is that we take the sphere and break it up into five non-measureable sets. While the geometry of the sphere is preserved in this, points in each piece do not move relative to each other, the instant that we break it into non-measureable sets we end up losing the information about the volume of the sphere. Using rotations and translations will then just preserve the non-measurableness of the sets. We then reassemble the pieces in a way that creates two spheres identical to the first. No rules were broken because the rotations and translations had no volume to preserve, and the five non-measureable pieces do not even remember their original volume so we are free to reassemble them in a way that gives us more volume than when we started with.
Banach-Tarski is not just about sizes of infinity. That stuff is simple. Banach-Tarski is a nontrivial mixture of Measure Theory (which tells us what volume actually means), the Axiom of Choice (which is guarantees that we can choose elements in a specific way) and some nontrivial things in Group Theory (which tells us how to use rotations and translations). | [
"The Banach–Tarski paradox is a theorem in set-theoretic geometry, which states the following: Given a solid ball in 3‑dimensional space, there exists a decomposition of the ball into a finite number of disjoint subsets, which can then be put back together in a different way to yield two identical copies of the ori... |
Why did clock and watch makers decide on only 12 hours instead of 24? How did a 12 hour clock face become standard? | It has to do with the cost of building clocks and clock towers. 12 hour clocks are cheaper.
I explained it in some detail in this previous thread [here](_URL_0_). | [
"The use of clock faces was part of the European technology received in Japan, and a number of arrangements were made to display Japanese hours on clock faces. Some had movable hours around the rim of a 24-hour clock dial. Others had multiple clock faces that could be changed with the seasons. To make a striking cl... |
To what extent did the Hittites make use of iron? | Iron is first attested in Anatolia in the third millennium BCE. An iron dagger with trace amounts of nickel was found in the "royal" tombs of Alaça Höyük (ca. 2300 BCE). Iron is better known, however, from Old Assyrian texts (2000-1750 BCE). During this time period, Assyrian merchants regularly traveled to Anatolia to trade textiles and other Mesopotamian products in exchange for precious metals. Iron was about forty times as valuable as silver in the Old Assyrian period.
In the Old Hittite period (1600-1450 BCE), iron was used especially for spears and sceptres during religious ceremonies, which served as symbols of the king's power. By the Middle Hittite period (ca. 1450-1350 BCE), the Hittites were also using iron for ceremonial axes, the king's lituus (a curved staff), and jewelry. An excerpt from the KI.LAM festival:
> Then the palace spear-man takes the iron spear from the king and gives it to the palace official.
> The first of the palace officials takes an iron axe from the last of the palace spear-men and gives it to the supervisor of the palace officials. The supervisor of the palace officials gives it to the king. The place on the axe where the engraving of the Storm God is, he turns that side toward the king...
Attestations of iron in Hittite texts really take off in the Hittite empire period (1350-1180 BCE), however. By this time iron was also used for cult idols, knives, daggers, and swords. Its use for jewelry declined, suggesting the metal was not quite as rare and impressive as it had been. That it was now measured by the mina like copper rather than by the shekel like gold and silver (as it had been previously) supports this conclusion.
The Hittites sometimes referred to "black iron" (AN.BAR GE6), which is possibly meteoric iron. A ritual for the construction of a palace refers specifically to the use of meteoric iron.
> They have laid foundations of silver and gold. The gold they brought from Birunduma. The silver they brought from Kazza. The lapis they brought from Mount Takniyara. The marble they brought from Kanisha. The jasper they brought from the land of Elam. The diorite they brought from the earth. The black iron of heaven they brought from heaven. Copper and bronze they brought from Mount Taggata in Alašiya.
Iron was worked by smiths (LÚ.SIMUG). The first step was to sort the raw material and purify it. The metal was then cast (*lahuwai*, "to pour") into ingots. Three types of iron are known - iron (AN.BAR), iron "from the furnace" (AN.BAR *ŠA* _URL_0_), and "excellent" iron (AN.BAR SIG5).
Iron does not seem to have been a significant metal for commerce and taxes. Andreas Müller-Karpe calculated the frequencies of metals in Hittite economic texts ("Anatolische Bronzeschwerter und Sudosteurop" in *Festschrift fur Otto-Hermann Frey zum 65. Geburtstag*, pp. 74-78). He found that 25% of taxes were paid in metal; of these taxes, 60%, 13%, and 8% were paid in copper, silver, and tin, respectively. Gold and iron had only one attestation apiece.
**Further reading**
Muhly, J.D. 1980. *The Coming of the Iron Age*.
Waldbaum, Jane. 1978. *From Bronze to Iron. The Transition from the Bronze Age to the Iron Age in the Eastern Mediterranean*.
Yalçın, Ünsal. 1999. "Early Iron Metallurgy in Anatolia." *Anatolian Studies* 49: 177-87.
| [
"The Hittites were also famous for their skill in building and using chariots, as the Battle of Kadesh demonstrates. The Hittites were pioneers of the Iron Age, manufacturing iron artifacts from as early as the 14th century BC, making them possibly even the first to do so. The Hittites passed much knowledge and lor... |
How are mineral seedbeds created? | A mineral seedbed is a growth medium that lacks significant amounts of organic matter.
Wildfire can create seedbeds like this by combusting all of the organic material out of topsoil, leaving behind a "sterile" mineral based layer for things to grow in. Areas with high erosion, desert climates, or limited existing vegetation can also have mineral seedbeds.
Some plants thrive in this medium because they are readily available to use inorganic materials for growth. These plants have little competition in the seedbed until the ecosystem builds up organic material. | [
"The purpose of a mineralizer is to facilitate the transport of insoluble “nutrient” to a seed crystal by means of a reversible chemical reaction. Over time, the seed crystal accumulates the material that was once in the nutrient and grows. Mineralizers are additives that aid the solubilization of the nutrient soli... |
who benefits from sending computer viruses out into the world? | Depends on what it does.
Some malware is designed to make the creator money. This includes things like the "scareware" programs that pop up, tell you that you have a virus and need to pay them $30 to clean it up. There are also viruses that try to steal your credit card information when you shop online, so they can sell that on the black market.
Other malware is a "just because" type thing. Someone has found a flaw in the way the computer is programmed and wants to show it off. There's an immense personal satisfaction in creating something from nothing, and I'm sure the creators of malware that made the news like the Blaster worm are quite proud of their 15 minutes of fame, even if they personally were never identified.
Then there's the espionage malware- stuff like Stuxnet that was designed specifically to infect Iran's nuclear reactors that was likely motivated by patriotism, and possibly sanctioned by one or more governments. | [
"Developments in mail systems, such as Microsoft Outlook, without sufficient thought for security implications, made viruses that indeed propagate themselves via email possible. Notable examples include the Melissa worm, the ILOVEYOU virus, and the Anna Kournikova virus. In some cases, a user must open a document o... |
why does the milk at the grocery store expire in 1-2 weeks but the milk at fast food places are good for over one month? | It's a different type of milk. You can get UHT milk/long life milk. It lasts longer and is fine for coffee etc but doesn't have the same taste as fresh milk. | [
"Due to the short shelf life of normal milk, it used to be delivered to households daily in many countries; however, improved refrigeration at home, changing food shopping patterns because of supermarkets, and the higher cost of home delivery mean that daily deliveries by a milkman are no longer available in most c... |
i've deeply cut my finger, what is my body's immediate response to this and what exactly is my skin, muscle and other tissues doing during the healing process? | Well, your immediate response is pain. The All severed blood vessels will constrict as much as possible to stop blood loss while other vessels proximal to the cut will expand, somewhat bypassing the affected area.
During the healing process, as long as everything is bandaged up tightly and in the right place, your body will just repair/regrow new cells to replace the damaged ones and reconnect everything. I'm pretty sure you run into problems if a muscle is mostly/completely severed though. You'll get scarring, which is basically super-fast growing tissue your body makes to close up the hole in you so it can make repairs without (even more) risk of infection. | [
"Although nerves tend to lie deep under the skin except in a few places such as the ulnar nerve near the elbow joint, they are still relatively exposed to physical damage, which can cause pain, loss of sensation, or loss of muscle control. Damage to nerves can also be caused by swelling or bruises at places where a... |
why is having netanyahu speak in washington so controversial? | I say this with a neutral point of view, not to make a point:
The Israel/Palestine conflict has led to a number of human rights issues and accusations of war crimes on both sides. Many people are opposed to the state of Israel's existence at all. The majority of foreign leaders who speak in Washington come from states that are universally recognized, and who are not openly associated with many of the terrible happenings in the Israel/Palestine conflict. | [
"Netanyahu's \"Bar-Ilan speech\" provoked mixed reaction from the international community. The Palestinian National Authority rejected the conditions on a Palestinian State given by Netanyahu. Senior official Saeb Erekat said, \"Netanyahu's speech closed the door to permanent status negotiations\". Hamas spokesman ... |
What sort of influence did the arrival of European settlers have on the style of warfare practiced in the Natal? What did Zulu military technique look like prior to contact? | To answer your first question:
Guns were present in Natal from the time Shaka Zulu created the Zulu Empire - Shaka even hired/conscripted very small numbers of Europeans with muskets to fight for him, although never in decisive or significant numbers.
The primary Zulu weapons from the time of Shaka Zulu until the Anglo-Zulu War in 1879 were a throwing spear, the short assegai stabbing spear, and the heavy knobkerry club. The spears would be thrown when the Zulu charge was about 20-30 yards away from the enemy - then the warriors would drive the charge home to use their assegai and clubs.
The European transition away from flintlock and caplock firearms around 1850-1870 lead to a glut of surplus muskets flooding the world market. A large number of these ended up in Southern Africa by way of traders in Natal and Mozambique. The most common firearm in Zululand by 1879 was the trusty old Brown Bess flintlock musket - by thenb it was so cheap, it could be bought by a Zulu warrior for about the price of a sheep.
The Zulus did some skirmishing - the "chest" of the bull formation would sometimes be preceded by shooters who'd throw down generally inaccurate harassing fire. Other warriors with guns used theirs as a kind of replacement for the throwing spear - they'd fire their guns at short range and then charge in to use their assegai.
I've written more about the subject of guns and Zulu tactics here:
_URL_0_ | [
"The Zulu are a significant case in African military innovation and change. Their system of war transformed large portions of the continent and their methods spanned both the pre-gunpowder and gunpowder eras. Several innovations appeared as part of the existing indigenous cultural mix, and their adaptation by burge... |
why do older phones (like sony ericsson) not start up without sim-card? | Older phones' main functions were provided over the cellular network. They used the SIM to make and receive calls and send and receive text messages. Older phones did not have the concept of WiFi or Apps used for something other than communicating. Hence there wasn't a point of the phone unless it had a valid SIM.
Current phones can be used for a plethora of activities like movie editing, recording, playing games, etc. and work over WiFi. So they can be used without a SIM. But at the same time, you cannot send messages or make calls while there's no SIM. | [
"\"SIM cards\" in developed countries today are usually UICCs containing at least a SIM application and a USIM application. This configuration is necessary because older GSM only handsets are solely compatible with the SIM application and some UMTS security enhancements rely on the USIM application.\n",
"Due to t... |
Why is it that there is a (approximately?) 50/50 chance of an offspring being male/female? | [Fisher's principle](_URL_0_):
Imagine there exists a population in which the majority of individuals born are female. In this case, it's in a female's long term reproductive advantage to produce male offspring, because it's easy for males to find females to mate with, but hard for females to find males. The result is that any genetic mechanism that allows for females to produce more males than her sisters will tend to spread, and vice versa if males are common, leading to a balance at 50%.
This balance can be upset, however, if the reproductive value of the two sexes is not equal, i.e. if offspring of one particular sex are *a priori* more likely to have reproductive success even with an even sex ratio (in which case genetic elements that favored an increased frequency of that sex would tend to spread).
Another thing that can upset this are selfish genetic elements, or "meiotic drivers". These genes distort the process of meiosis so that they make it into greater than 50% of the gametes, and thus tend to rise in frequency in the population. They can arise either on autosomes or sex chromosomes, but when they arise on the sex chromosomes, they can impact the sex ratio of the population, even to the detriment of the population's long term well-being.
More broadly, the fact that an individual genetical element can gain a massive reproductive advantage from cheating during meiosis has led many to speculate whether much of the complicated machinery of genetic recombination is actually partially a defense mechanism to keep these kind of selfish genetic elements from exploiting meiosis. (good sources: citations 4, 12, 13, 15, 16, 19, and 25 in [this preprint](_URL_1_) written by some folks in my lab) | [
"The ratio of the sex of newborns is improbably 50/50 male/female, according to the frequentist test. Yet 50/50 is a better approximation than most, but not \"all\", other ratios. The hypothesis formula_64 would have fit the observation much better than almost all other ratios, including formula_65.\n",
"Genetica... |
Why did Roosevelt issue so many more executive orders in comparison to other presidents? | First, Roosevelt was in office for 12 years, so the orange bars (number per year) is a more useful measure. And before FDR, executive orders weren't always tracked that carefully.
Second, a lot of the government regulatory agencies that we now take for granted were *invented* as part of the New Deal. A number of FDR's orders were to set industry output and market shares in the desperate hope that central economic planning could help the nation recover from the Depression.
Third, the exigencies of fighting a world war led to various military and home-front decrees. It's also useful to remember that Roosevelt spent five years before Pearl Harbor maneuvering the US into position to fight the war he could see was inevitable, preparations that isolationists resisted. A lot of those defense preparations and pre-1941 behind-the-scenes aid to Great Britain necessitated executive orders.
[This opinion piece includes some useful historic background.](_URL_0_) | [
"Most Americans opposed giving the president any more power, as a Gallup poll found in April 1938. Nevertheless, after winning the approval of Congress, Roosevelt signed the Reorganization Act of 1939. Roosevelt then established the Executive Office of the President, which increased the president's control over the... |
Late medieval/early modern urban geography (?) - how was the population spread in a country in the 1500s? | RenlyWHW:
There are a lot of questions here, but here are a few notes that might help.
First, England's population distribution from 1550-1700 was somewhat unusual for Europe, given that London vastly outstripped every other city in size (it became what demographers call a 'primate city,' a city that vastly larger than the next city in a region/country). Spain, the Netherlands, and France, by contrast, had several large urban areas that were more balanced rather than a single sprawling metropolis and a bunch of small merchant towns, as in England.
If you are interested in population spread across counties, you might look at [this project being conducted at Cambridge] (_URL_0_), where they are figuring out population density at the ancient county level and, even smaller, at the parish level for a variety of dates including 1670. That will give you a sense of population density per square mile at a fairly granular level in different parts of the country.
One final note: not a lot of land in England by the seventeenth century was truly unoccupied (remember, the whole modern UK is only the size of Oregon; England alone is slightly more than half that). A combination of the expansion of sheep farming in the sixteenth century and the sale and destruction of the great royal forests in the seventeenth century meant that the areas that had been untouched were slowly eroded by farming and forestry.
Hope this is helpful! | [
"\" also led to a rapid population growth throughout East Central Europe. During the 12th and 13th centuries, the population density in persons per square kilometre increased, for example, from two to 20–25 in the area of present-day Saxony, from 6 to 14 in Bohemia, and from 5 to 8.5 in Poland (30 in the Cracow reg... |
why are computer not used in sports games? for balls/strikes/safe/outofbounds etc... | It's mostly tradition, umpires don't want to be out of a job, and people in general don't like change. But there can also be a deeper meaning.
Take racewalking as an example, an olympic event where one must move as fast as possible without running, aka without ever having both feet off the ground at the same time. Race officials watch the racers at all times, and if anyone makes 3 mistakes in the run, they're disqualified.
Using high speed cameras, you can see that professional racewalkers actually do have both feet off the ground on most steps, but it's not detectable by human senses. If the human officials were replaced by robots, the entire sport would be completely changed.
And after all, all sports are made of arbitrarily created rules, if you change the rules you can destroy the entire sport (although not many people would miss racewalking). | [
"Expert players are able to win against any computer player without giving a point away, since the AI isn't very well developed (and there are no difficulty options) and it's hard to miss a ball. The most usual tactic is to lure the opponent into the net (by making low shots), and then expect he bounces against a m... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.