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How large was Charlemagne's army? (at the beginning of his reign and his height) | I think this is an interesting question, certainly it is to me, and it's a shame you haven't gotten a good answer yet. So I decided to have a look into it for you in the meantime. I should emphasise that I don't know much about this period and so, until I read a few things on the matter, I knew next to nothing of this issue.
I found a very surprising answer to your question in a journal article. After pointing out the demographic size of Charlemagne's empire was around 20 million people (351-2), the author claims that "In light of the size of the population of Charlemagne's empire, it should not be surprising that those who study Carolingian military demography now see the emperor as being able to put into the field for offensive military operations, intended for the conquest of enemy territory, several armies in any given year, which when taken in the aggregate could reach a total in the neighbourhood of **100,000** effectives" (Bachrach 352-3).
As a student of the Roman military, and understanding as I do the incredible logistical organisation and resources that made the size and reach of Rome's armies so formidable, I find it incredible that a medieval empire, even one was large as Charlemagne's, could field such forces, even if only for a single campaign! Since I personally find this a fascinating claim, I went through Bachrach's footnotes for this number. Bachrach claims that, despite what I thought personally, that the Carolingians could raise very large armies is much the majority position for medieval military specialists. Bachrach cites a single specialist in the field who resists the general rule that the Carolingians could field huge forces, one Timothy Reuter. Reuter apparently sees individual Carolingian armies that could campaign for any extended period as not much bigger than 2000-3000. However, his selective use/misuse of casualty lists to support such low figures is criticised by Bachrach, and the latter's case seems sound. Indeed, going from casualty lists, such a contemporary list giving a number of "5000" for a defeated Viking army in 880 AD, it seems such sources could easily be used to support a view counter to Reuter's.
Charlemagne's status as by far the greatest European power of his time, and wide range of his campaigns (stretching into the Pyrenees, Saxony, Bavaria and Italy: see Bennett 89-91), do make it seem as if large and yet sustainable fighting forces that could be summoned readily would be necessary for such campaigns. With the fall of the Roman government in Europe, and the settlement of most barbarian groups in some place or another, warfare in Europe became a local rather than a state affair, with the corresponding reduction in available resources. According to the Cambridge History of Warfare, it is Charles Martel, Pepin (d. 768) and of course Charlemagne were the first after the fall of Rome to re-develop a centrally controlled military system (Parker 68). The Cambridge History gives details of how this recruiting system works (though the authorities came up with various formulae), which may give us some insight into how such incredible armies could be used for organised offensive campaigns in Europe even after the collapse of the Roman logistical system:
The selection of levies from various territories formed the basis of the Carolingian Army. Apparently rich men with twelve estates or more were required to muster with horse and armour when called. Men with five estates were also liable to being mustered, but with less equipment. Those living close to the field of operations could be called up with three or four manors, and landowners with as little as half an estate were formed into "partnerships" with a total wealth of five estates, and were required to provide and equip a soldier for the levy. Like the Merovingians, the Carolingians required all free men to take oaths of fidelity to the king and be registed on the rolls of their county. This identified those eligible to serve in both local defence forces and the levy, and gave central control over the "many thousands of highly professionalised fighting men who served in the personal armed followings of the lay and secular magnates" (Cambridge History 70).
According to the Cambridge History, Charlemagne controlled an even larger area than the Byzantines, who had lost the battle of Yarmouk and with it nearly half their territory. "Charlemagne...could muster for simultaneous major campaigns perhaps **150,000** men, of whom at least 35,000 were heavily armed mounted troops. Indivdual armies of 35,000 to 40,000, though hardly common, were not unknown" (70). Importantly, it is mentioned that "Charlemagne's grandons ...among whom the empire was divided in 843..tended to deploy smaller armies numbering from 8-10,000 in comparatively restricted theatres of operation."
For purposes of comparison in this period, the Byzantines, who had consolidated their position by the mid-800s, could field a regular army of around 120,000 troops (Cambridge History 75), with a field army of 25,000, supported by a population of eight million. With the breakup of the Carolingian empire, such huge armies disappeared in Europe again: King Harold levied 8000 troops at Hastings, and French leaders in the 10th and 11th centuries fielded relatively large armies of under 10,000 (76). William the Conquerer invaded England with 14,000 troops, including mercenaries. However, the army raised for the First Crusade under the aegis of the Church and led by a Bishop, was about 60,000 men. This was huge for an individual army, "double the order of magnitude of those raised by Charlemagne, and its logistic range was considerably greater..." (77). Of course, even in its debilitated state the Late Roman Empire had a standing army of something like half a million troops, though its field armies were still about the same size as Charlemagne's.
**So there you have it. Charlemagne's armies could easily total 30,000+ men, and he could field several at a time if necessary, for a total of 100,000+ troops. The development of this incredible military capacity began with Charles Martel and peaked under Charlemagne. The numbers I have given were for the Carolingian empire, which existed from AD 800, and Charlemagne died in 814. At the start of Charlemagne's reign, when he had not conquered all the territory that he would later come to rule, his army would have been smaller. But I don't know how much smaller.**
Thank you for asking this question so I had the opportunity to learn so much on the topic!
Sources:
Bachrach, Bernard. "Charlemagne and the Carolingian general staff", The Journal of Military History, 2002, 313-57.
The Cambridge History of Warfare, ed. Geoffrey Parker, 2005.
Bennett, Judith. Medieval Europe, A Short History: Eleventh Edition, 2011.
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"The German historian Martin Lintzel argued that the figure of 4,500 was an exaggeration, partly based on the theory of Hans Delbrück regarding the small size of early medieval armies. On the other hand, Bernard Bachrach argues that the 4,500 captured warriors were but a small fraction of the able-bodied men in the... |
different types of exercises | Different exercises help work different parts of all muscles. It's good to switch up the exercises to keep shocking and tearing up different parts of your muscles. | [
"Exercises include mental and physical conditioning, reasoning, meditation and contemplation. They are designed to regulate and develop the different functional levels of the human system. Many exercises are designed to promote understanding of oneself and of others; and then there are exercises of a more fun natur... |
the bible | Way too broad a question. Nobody can explain the complexities of the bible to a five year old.
At best you can say the old testament is for the Jews and the new testament is for the Christians. The same way the book of Mormon was for the Mormons or the Qur'an was for the Muslims. | [
"The Bible (from Koine Greek τὰ βιβλία, \"tà biblía\", \"the books\") is a collection of sacred texts or scriptures. Varying parts of the Bible are considered to be a product of divine inspiration and a record of the relationship between God and humans by Christians, Jews, Samaritans, and Rastafarians.\n",
"BULLE... |
If hair and fingernails are both made of keratin, why do I lose my hair but not my nails from chemo? | It's less to do with the keratin and more that the follicles have rapidly dividing cells, which are targeted by chemotherapy. Nails are also affected by many chemotherapy drugs. Fingernails can become weak and brittle during chemotherapy. They may fall off after several rounds of treatment, but this is less common. Lines, both horizontal and vertical can form, and can appear lighter or darker than the rest of your nail. Fingernails are affected more than toenails, and usually grow out normally again about 6 months after finishing treatment. [Source.](_URL_0_) | [
"Keratin is a protein which is found in skin, hair, and nails. It is most resistant to the enzymes involved in proteolysis and must be broken down by special keratinolytic microorganisms. This is the reason that hair and nails are commonly found with skeletal remains.\n",
"Keratin () is one of a family of fibrous... |
Was Sun Yat-sen a successful revolutionary leader? | First off, you have to define what makes a revolutionary leader "successful." Did he contribute to the downfall of Qing? Absolutely. Did he unite the country? Far from it. Were his ideas for China revolutionary? Not quite.
Given that much of his "revolutionary" activities were actually done overseas (he spent a lot of his time gathering support from overseas Chinese; Tongmenghui started in Japan, etc.). Indeed, his three principles did get widespread attention, but none of this was new: late Qing and early Republican revolutionaries had already developed extensive ideas that incorporated democracy and modernisation. I am not sure why you mentioned May Fourth either; May Fourth was a separate entity organised by Peking University students which Sun Yat-sen actually criticized for being too radical and corrosive. I believe you meant the [New Life Movement](_URL_0_), which was something else entirely.
Moreover, organisations such as the Tongmenghui were, although influential, far from united and hardly successfully "revolutionary" in the pragmatic sense. Sun was a moderate, whilst many other individuals ranged from Chinese anarchists like Li Shizeng to left-leaning intellectuals such as Cai Yuanpei, who would later serve as the president of Beida (Peking University). As a "revolutionary" in this sense, Sun clearly fell way short.
What made Sun successful however, was his ability to gather support, put himself nationally as a leader of a major party contender, and create a party that would later dominate China's political history. Given the social, political, and economic mess that China was in before and after the collapse of the Qing dynasty, Sun was arguably successful in what he set out to achieve. However, it would be doing a disservice to the myriad other revolutionaries to ascribe a disproportionately grandiose reputation to him as so many scholars have done thus far. | [
"Throughout his lifetime, he was a vocal supporter for Sun Yat-sen and his revolution to overthrow China's Manchu-led Qing dynasty. An example of this was his defence of the 1884 Praya rioters dubiously charged by the colonial administration with the offence of refusing to accept work, the riots being an event Sun ... |
Why did German high command find the 'Final Solution' to be a worthwhile endeavor? | The first thing you have to do is understand the the goal to be Judenrein, clean of Jews, was a central part of Nazi policy. Racial purity was a central concern of the Party, and to be part of it was to believe in working towards the goal of a Germany cleansed of Jews, at least, on paper. It was also to believe in the superiority of the Aryan race, the need for greater lebensraum (living space for Germans and ethnic Germans), the inferiority of Poles, Slavs, Romani, anyone visually not white, the disabled, etc. Hannah Arendt's Eichmann in Jerusalem: A Report on the Banality of Evil might help you understand the mentality.
Beginning in 1933, Nazi policy towards the Jews was to make life as unpleasant as possible so that they would leave. Their anti-Jewish laws were passed under the assumption that the Jews would have someplace to go, or, in other terms, that the international landscape was one open to accepting Jewish refugees. This was not the case. And as Germany made life increasingly unpleasant for the Jews over the course of the 1930s, the Nazis grew frustrated by the relatively small number of Jews who were leaving. Now, there are complex reasons behind this, some having more to do with gender than with anti-Semitic immigration policies, but the crux of the matter is, that, by 1938, not nearly enough Jews were out of the Third Reich. Kristallnacht succeeded in pushing more of them out, but the fact remained that there were extremely few places willing to receive them (I can dig up some stats on this if you'd like). The goal to make the Third Reich Judenrein by way of making life so unpleasant that the Jews would be forced to leave didn't work because there was nowhere for them to go.
The Nazis considered mass deportation as a Final Solution. Madgascar was considered as a potential place where they could move the Third Reich's Jewish population. Siberia was also considered, I believe.
In the first six weeks of Operation Barbarossa, the Nazi Invasion of the USSR beginning in June 22, 1941, German troops would commit mass murders of any Jewish community they came across while making their way through the Western Soviet Union. This, combined with the failure of the Final Solution by way of forced immigration, and by way of forced relocation to territories not yes conquered, led to Hitler's decision to deport the Third Reich's Jews to the occupied East, and achieve the Final Solution by way of mass extermination. This iteration of the Final Solution was put into place on October 15, 1941.
This answer condenses a lot of highly complex issues, so please don't be shy with follow-ups! | [
"The nature and timing of the decisions that led to the Final Solution is an intensely researched and debated aspect of the Holocaust. The program evolved during the first 25 months of war leading to the attempt at \"murdering every last Jew in the German grasp\". Most historians agree, wrote Christopher Browning, ... |
why does my automatic transmission car still have l, 2, and 3 on the gearshift, and when would i use them? | Going down a steep or not quite steep grade to use the engine for braking. | [
"Some automatics, particularly those fitted to larger capacity or high torque engines, either when \"2\" is manually selected, or by engaging a winter mode, will start off in second gear instead of first, and then not shift into a higher gear until returned to \"D.\" Also note that as with most American automatic t... |
if the dna of an organism contains all the building plans for the body, how does a single cell know its location and needed function if all the first cells start the same? | The key here is to recognize that while almost all cells in the body contain the same set of genetic information, not all genes (the segments of DNA that codes for a specific protein) are expressed in all cells. **Regulation of gene expression** is at play here.
Cells can (and regularly do) receive signals that tell it which genes to express. Different cells receive different signals - > different cells express different genes - > different cells make different proteins. Having different sets of proteins allows one cell to function, look, behave, etc. differently from another.
A cool example that I was taught was how our fingers develop. Early in a developing fetus, the limbs don't have fingers/toes (think stumps). At a certain point though, cells at the extremities get the signal to basically commit cell-suicide. The death of these cells leads to the space between our fingers and toes. A failure in this process is how some people have webbed fingers! | [
"Each human cell contains around two metres of DNA, which must be tightly folded to fit inside the cell nucleus. However, in order for the cell to function, proteins must be able to access the sequence information contained within the DNA, in spite of its tightly-packed nature. Hence, the cell has a number of mecha... |
why do we sometimes feel tickled when the tickler is just pointing at our bellies? | If it weren't for the nerves in your belly, you wouldn't feel anything when being tickled. When you're being pointed at your brain knows it's about to be tickled and starts to give the sensation before it happens as a form of anticipation. Same way you might feel pain on your body when you see pain inflicted on the same body part of someone else. | [
"Charles Darwin theorized on the link between tickling and social relations, arguing that tickling provokes laughter through the anticipation of pleasure. If a stranger tickles a child without any preliminaries, catching the child by surprise, the likely result will be not laughter but withdrawal and displeasure. D... |
engine efficiency in the future and the internal combustion engine | You have a lot of things going on in this. A piston is Pushed down by the burning of the compressed Gas. That downward stroke is know as the "power stroke" while forcing it down and driving the car, it also pushes up the next piston.
There are lots of Engine designs out there that push the internal combustion engine into better efficiency numbers, but it comes at a cost, difficult to manufacture, and specialized Maintenance. So there is a lot of RD around making cars more efficient, just not as fast as you would think.
Traveling by Bending Time and or space is a lot more complex and involves a lot of theory that will go way beyond a ELI5 | [
"The efficiency of internal combustion engines depends on several factors, the most important of which is the expansion ratio. For any heat engine the work which can be extracted from it is proportional to the difference between the starting pressure and the ending pressure during the expansion phase. Hence, increa... |
We've always been at war with Eastasia. Why did the conflict start in the first place? | Friend, I think you've gotten things mixed up, we're at peace with Eastasia, we've always been at war with **Eurasia**. I suggest reporting to your nearest Ministry of Truth official to make sure you're remembering the correct account of history. | [
"The emergence of newly independent countries in Africa and Asia that used the borders of the imperial partitions later led to further conflict. In many cases this meant that historically antagonistic ethnic or religious groups now needed to share the same country or that several nations held territorial claims ove... |
light-based computing | Instead of sending an electrical signal down a wire, which is received by a device sensitive to electricity, you'd shine light through optical fiber or across open space, and the receiving device is sensitive to light.
Computers use TINY "switches" (transistors, in a normal electrical computer), they also run them VERY fast to move/manipulate information very quickly.
The problem with electricity is it can affect nearby circuits through capacitance (where voltage changes "leak" onto whatever is nearby) and inductance, where changes in current flow cause magnetic fields which affect electrical flow in whatever is nearby. Again, computers are small and the signals are very fast. We'd like to make them even smaller and the signals even faster. These electrical properties become limitations.
Light doesn't exhibit those particular behaviors. It can also travel faster than electrical charge in some materials.
The problem is making devices respond to light more quickly and efficiently than our current electrical transistors. Even small delays, errors, or larger devices would prevent us from building a smaller/faster computer than what we use now... and again, that would be the whole point.
So there are theoretical benefits. Practical? Not yet, and I'm not sure we *know* whether this will ever work in the real world to the extent we'd like to see. | [
"Specialty areas of optics research include the study of how light interacts with specific materials as in crystal optics and metamaterials. Other research focuses on the phenomenology of electromagnetic waves as in singular optics, non-imaging optics, non-linear optics, statistical optics, and radiometry. Addition... |
Does light refract in clouds as it does in water? | Yes. The refraction of light in water drops creates a rainbow. This only happens if you, the water drops, and the light source are at just the right geometry. | [
"Water attenuates light due to absorption which varies as a function of frequency. In other words, as light passes through a greater distance of water color is selectively absorbed by the water. Color absorption is also affected by turbidity of the water and dissolved material.\n",
"Another form of atmospheric di... |
Were there German spies that were found, captured, and executed in the United States during World War 2? | I have not seen that documentary, but did it mention Operation Magpie: Gimpel and Colepaugh?
William Colepaugh was a disgruntled MIT grad who eventually fled to Germany and volunteered to come back to the US as a spy. Of course they problem with assets with that kind of motivation is that they tend to be very erratic, so they paired with with a professional operator and clandestine radioman, Erich Gimpel. Gimpel understood that his task was to keep this flake on track.
Colepaugh convinced the SS that he could infiltrate the Manhattan Project, but needed a suitcase of small USD today worth a half million and 99 diamonds for when the US economy collapsed and the USD was no longer accepted. He justified this by overstating the cost of living the US by almost an order of magnitude. The Germans having typically never seen life beyond East Coat high society, believed him.
So on November 29, 1944 the two men successfully landed in rural Maine... adorned in German Naval Officer uniforms stripped of insignia. Surprisingly, the insertion and initial cover story actually worked. They claimed to be travellers whose car broke down and they hailed taxi's and trains all the way through Boston and into Manhattan. They successfully rented an apartment in Times Square.
They settled in Manhattan, but the Christmas festivities may have taken their toll on Colepaugh. Having already argued with Gimpel about wanting time to watch New Yorkers ice skate and go carolling, Colepaugh went to Grand Central Station on December 21, 1945 and boarded a train to visit an old college buddy.
On December 23, 1944 he confessed to his friend, who promptly turned him into the FBI. Colepaugh told the FBI everything and they rolled up Gimpel. (Interestingly enough, Colepaugh already had a record with the FBI back to 1940 when he was first caught making contact with the Germans while in the US Naval Reserve.) Operation Magpie fell apart after less than a month on ground.
As spies, both were sentenced to be hanged on Valentine's Day, 1945. However, both their executions were stalled by the death of FDR, as it was tradition not to perform executions during a time of mourning. By the time the state of mourning was over, VE day had happened, and Truman decided life in prison was a more appropriate sentence, and they both were sent to Alcatraz.
Gimpel would obtain a full parole in 1955, and returned to West Germany. Colepaugh was paroled in 1960, and resettled in PA, where he opened an office furniture shop, based on the carpentry he learned in prison.
Both men were still alive until fairly recently. Colepaugh became a pillar of the community in a small town in PA until his death from Alzheimers in 2005. Gimpel wrote several books about his work as a German spy and eventually resettled with the German ex-pat community in Sao Paulo, Brazil. After 9/11, there was a new found interest in spies and traitors, so some of his work has been republished fairly recently. He also did an episode of "War Stories with Oliver North" in 2003, "Agent 146: Spying for the Third Reich." Gimpel died in 2010.
The FBI declassifed much of the casework on Colepaugh. "Counterintelligence in World War II" did almost an entire chapter on him:
_URL_1_
If you're looking for a bit lighter read, America in WWII also did an article:
_URL_0_ | [
"During World War II, German spies Erich Gimpel and William Colepaugh landed by submarine in Hancock, then traveled to New York City. These spies would eventually be captured, tried, and sentenced to death before their sentences were commuted and they were eventually released.\n",
"Ernst Peter Burger (September 1... |
can someone explain the wars in afghanistan and iraq like i'm a five year old? | As simply as i know, without theory. Afghanistan-We invaded Afghanistan to catch Osama Bin Laden and remove the Taliban government that was supporting him. Iraq-We invaded because according to intelligence, Sadam Huessien (sp?) Had access to weaopons of mass destruction (WMD's) that threatened the US's national security. Again that is as basic as i believe it to be. A lot of it after these years has become speculation and conspiracy, but those were the original official reasons. | [
"The Afghanistan conflict (, ) is a series of wars that has been fought in Afghanistan since 1978. Starting with the Saur Revolution military coup, an almost continuous series of armed conflicts has dominated and afflicted Afghanistan. The wars include:\n",
"Subsequent chapters on Iraq and Afghanistan document cl... |
what is the difference between toilets where you press a button and it flushes automatically, and toilets that draw water only as long as you keep the button pressed? | Usually, the flapper has a void area that traps air so that it stays afloat by buoyancy until the weight of the incoming water used to fill the tank overcomes the buoyancy of the flapper.
[_URL_1_](_URL_1_)
Usually, the "non-automatic" flappers do not have this feature.
[_URL_0_](_URL_2_) | [
"Toilets without cisterns are often flushed through a simple flush valve or \"Flushometer\" connected directly to the water supply. These are designed to rapidly discharge a limited volume of water when the lever or button is pressed then released.\n",
"Because it is a development of the traditional Australian fl... |
AskScience, what part of Earth has the smallest average temperature range? What part has the most hospitable temperature range? | I'm not going to try and answer the part about 'most hospitable' -- humans live all over the planet, and people express preferences for tropics, mid latitudes, or snowy climes.
Average temperature range, though, I can do. Using the NOAA land temp [data](_URL_0_), I made a map of the areas of the globe with the most temperature variability in monthly means from 1948 to 2011. It's [here](_URL_1_).
You can see that the tropics are the most stable region and the arctic has large fluctuations. The scale is standard deviation in degrees Celsius. | [
"The mesopause is the point of minimum temperature at the boundary between the mesosphere and the thermosphere atmospheric regions. Due to the lack of solar heating and very strong radiative cooling from carbon dioxide, the mesosphere is the coldest region on Earth with temperatures as low as -100 °C (-148 °F or 17... |
X and Y Chromosome-carrying sperm | There is no evidence to support a difference in swimming speed. However, the difference in the mass of X and Y chromosomes _is_ used in many artificial sex selection methods. | [
"In humans, a normal ovum can carry only an X chromosome (of the X and Y chromosomes), whereas a sperm may carry either an X or a Y (a non-normal ovum can end up carrying two or no X chromosomes, as a result of an irregularity at either of the two stages of meiosis, while a non-normal sperm cell can end up carrying... |
How does fuel consumption and potential nuclear weapon enriching work in nuclear power plants? | National soverignty is a big issue. Signers of the NPT have a right to nuclear power, including domestic production of all aspects. This is as long as they allow the IAEA to inspect. This includes the ability to not only enrich uranium, but make fuel and even reprocess. Japan does all of these and is not a nuclear weapon state. In the case of Iran, they want to have the full cycle available to them because it is in their rights. The US, rightfully so, doesn't see the point of Iran having enriching capabilities. Iran counters saying they have a research reactor, and research reactors typically use highly enriched uranium or medium enriched (around 20%).
The problem is going from natural uranium to HEU (greater than 20%) is long costly. Going from 20% to weapons grade (80%) is easy and pretty cheap.
There is not a 1-1 ratio from nuclear facilities. Reactor fuel is typically 3-5% U-235. It goes in and after a few years will be removed. Now the IAEA can keep track of it. However, reactors produce a lot of Pu-239. That can also be used in weapons and needs to be tracked. People don't realize that a lot of the power produced in nuclear reactors comes from plutonium fission and not uranium. That is due to the Pu build up. If there are proper safeguards in place, no one worries about fuel diversion. However, if Iran builds a reactor with online refueling, that can be a big issue.
One way to prevent the material from being weapons usable is to make sure the fuel is in there for long periods of time. That causes a buildup of other Pu isotopes that can predetonate weapons. However, even then one can use enrichment processes to overcome that. In reality, the only true method to prevent proliferation is to make sure only a few countries enrich and reprocess fuel. | [
"Many stages of the [[nuclear fuel chain]] — mining, milling, transport, fuel fabrication, enrichment, reactor construction, decommissioning and waste management — use fossil fuels, or involve changes to land use, and hence emit carbon dioxide and conventional pollutants. \n",
"The most common fissile nuclear fue... |
how does a linear induction motor work? | Alright, the only word in there you gotta worry about is 'induction'. 'Motor' just means it moves stuff, and 'linear' just means it moves stuff in a straight line (or close to it).
As for 'induction': When you've got electricity moving, it can create a magnetic field (i.e. what magnets make). That magnetic field can move stuff like you could with a magnet if you work the electric current just right. How do you work it just right? Well you basically line up a row of electromagnets (i.e. magnets you can turn off and on, or those pink things in figure 23 in that pdf) ~~and turn them on/off as they move along the iron stator (basically a chunk of iron that's attracted to magnets) so that the magnets are always getting pulled forward.~~
This kind of motor has two main advantages. One is that since nothing needs to be touching, you reduce friction, so things can go faster. The other is that the motor doesn't need much in the way of moving parts since it's all electricity, so things don't wear out as fast.
Does that help?
EDIT: See later post. Read a few things wrong in my first read of the pdf. | [
"A linear induction motor (LIM) is an alternating current (AC), asynchronous linear motor that works by the same general principles as other induction motors but is typically designed to directly produce motion in a straight line. Characteristically, linear induction motors have a finite primary or secondary length... |
How accurate is bill wurtz's "history of japan"? | You might want to check out this previous post on this question.
_URL_0_ | [
"A reviewer at the \"Internet Bookwatch\" said the book is not just \"a dry historical record\", but is \"aptly presented\", well researched and \"a worthy addition to World War II history shelves\". \"Kirkus Reviews\" called the book \"A gripping recreation of the last ten days in the life of HIJMS \"Yamato\"\". I... |
Is there a clear neurological distinction between addiction and just really wanting something, or are they on the same spectrum? | Drugs can "hijack" the hedonic system of the brain, or the "reward" system in such a way that drugs become a priority equal to or greater than basic survival like food and water.
This has been demonstrated on rats and mice using both drugs like cocaine and also by directly activating their reward pathways through electrical stimulation, i.e. electrodes were attached and when the mouse pushed a lever, it activated the reward system. The mouse went as far as to completely ignore food and water and repeatedly push the lever. I don't have access but maybe someone else can find this study.
How that translates to humans we are still figuring out, but as of now we assume it works more or less the same way. Cravings for drugs can overpower those for food and water, they are much different than just "craving a cheeseburger" (for a normal individual without any addictions).
Now I'm not saying drug addicts will starve themselves to death but when given the choice between food and drugs, most will spend their money on the drugs and "worry about food later" which leads to the typical addict lifestyle and health complications. | [
"Addiction is defined by scholars as “a reliance on a substance or behavior that the individual has little power to resist.” Substance-based addictions are those based upon the release of dopamine in the brain, upon which the range of sensations produced by the euphoric event in the brain changes the brain’s immedi... |
why is jackie robinson such a big deal in baseball, while we don't ever talk about the first black football, basketball , hockey, etc... players? | It's less that he played baseball, and more that he was the first black athlete to play in a white team period.
He's up there with Rosa Parks for "firsts for African Americans" in the civil rights movement. | [
"Jackie was a college educated man who had been an officer in the service and who played at the Triple-A level. Jackie was brought in by Branch Rickey specifically to be the first black player in major league baseball. Larry Doby came up as a second baseman who didn't have time to get his full college education, an... |
What kind of mutations would cause bacteria to be immune to antibiotics? | There are a ton of ways bacteria combat antibiotics and they're all just a little bit different depending on the bacteria and the antibiotic used to kill them. However, it always boils down to the bacteria doing one of three things:
1. **They can destroy the antibiotic.** This can be done either outside of the cell in the case of Gram + bacteria or in a sort of in-between space called the periplasm in the case of Gram - bacteria. Basically the bacteria make an enzyme, such as beta-lactamases, that act on the antibiotic, rendering it useless. In the case of beta-lactamases, it's clipping the beta-lactam bond.
2. **They can restrict the access of the antibiotic to the target.** There are several ways to do this. In Gram - bacteria, the antibiotic enters the cell first through "holes" in the outer membrane called "porins". The bacteria can reduce the number of these porins and therefore reduce the amount of antibiotic that enters the cell. In Gram + bacteria, they can increase the thickness of the glycoprotein layer so antibiotics get caught in that. This is the mechanism by which vancomycin, previously effective in pretty much every Gram + bacteria, is inhibited.
3. **The bacteria can make changes to the target of antibiotics.** Antibiotics rely on a specific binding site in bacteria to act upon in order to inhibit whatever it is that it's meant to do. If a bacteria changes the way its ribosomes look, the antibiotic doesn't recognize it and the bacteria can go right along making proteins as usual.
All of these things cost the bacteria a great deal of energy and/or efficiency. It's not normally better to have these traits but if the bacteria are put through a stress like the presence of antibiotics you end up with dead bacteria and less efficient bacteria.
Now that the I have to background out of the way, we can get to how the bacteria acquire the genes to pull this off. Bacteria are different from our cells in the sense that they have two separate sources of DNA. The first is chromosomal DNA which it picks up from a few sources.
1. It is passed down from its "parents". They simply get the genes from the ancestors. This doesn't really explain how bacteria "acquire" mutations, but it helps explain why they hang around.
2. It is dropped off by viruses that pick it up from another source that may or may not be bacteria. There are viruses that encode their genes into the genome of their host, which can sometimes be beneficial for the host.
Also, the bacteria have something called "plasmids" which are basically small packets of DNA that float around in the cytoplasm. These have their own DNA and activating conditions and have functions from antibiotic resistance to the ability to make proteins that digest lactose. Either way, they can be shared among bacteria in several ways. It doesn't even have to be the same species of bacteria! So say there is a bacteria that is resistant to a drug by way of a plasmid. If that bacteria dies or gives it to another bacteria by other means, now we have two bacteria that are both resistant to antibiotics that didn't necessarily descend from one another. This can explain how bacteria that had never seen a certain antibiotic could develop resistance in a few years. Say a bacteria lives in the same environment with a mold that makes penicillin for thousands of years. This bacteria may not necessarily fare well in humans, but it does have a plasmid for resistance to penicillin that it can pass on to a bacteria that does.
Which brings me to my last point, that true natural mutation is extremely unlikely to bring about antibiotic resistance, especially in the timeframes that we're talking about. It does happen but for the most part it can be explained otherwise.
If bacteria become unaffected by today antibiotics, which might seem nigh, then we'd have a bacteria that is extremely inefficient. Keep in mind that on top of killing everything we throw at it, it has to fend off our immune system and other environmental stresses, so if it grows too slowly it will be beaten by other means. There are a lot of different antibiotics and antibiotic combinations that pretty much guarantee that we can treat it somehow. I don't see an antibiotic being resistant to EVERYTHING, but I do see one that would be hard enough to treat that our patient would die before we figure out what it responds to.
As for the diseases, it could really be anything. Unless the bacteria makes some sort of toxin, it would probably be just generic major infection symptoms. (Septicemia, toxic shock syndrome, meningitis, etc.)
I'm hesitant to answer the last question because I'm bordering speculation, but I'd imagine we'd contain it just like any other outbreak, although it might be treated more like a virus because that's the closest example I can think of that we don't really have an answer for. Think of Ebola. It's this awful disease that pops up in small pockets every once and a while but is mostly contained with quarantine, education, and vigilance.
So to answer your question shortly:
Time. Anything. Similarly to viruses.
If I'm wrong on anything feel free to PM me and I'll change it.
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"Some bacteria are naturally resistant to certain antibiotics; for example, gram-negative bacteria are resistant to most β-lactam antibiotics due to the presence of β-lactamase. Antibiotic resistance can also be acquired as a result of either genetic mutation or horizontal gene transfer. Although mutations are rare... |
why do we have telescopes that are able to see the far reaches of the galaxy, but we can't use this technology to zoom into the moon and see hq images of the apollo landing site? | The hubble space telescope (which is one of the best) has a resolution of 70 yards (something like 65 meters), which is not enough to see the landing site (everything left on the moon is about 10 meters).
In the 2009 NASA launched the Lunar Reconnaissance Orbiter (LRO) to study the moon surface, and of course, a mission to the apollo 11 landing site has been programmed ([this](_URL_1_) is one of the image LRO took: the Apollo 11 is the white dot with a very long shadow in the middle) (You can find [here](_URL_0_) all the other image of the landing sites). In the photo of the Apollo 14 you can even see the tracks made by the astronauts.
Some times ago, 2002 I think, European astronomers said that the Very Large Telescope (VLT) could be used to get HD images of the landing site. The resolution of this telescope is very high: you could see the distance between the headlights of a car. However, these images have not been released yet. | [
"The space telescopes were to observe in the infrared part of the electromagnetic spectrum. As well as studying extrasolar planets, the telescopes would probably have been useful for general purpose imaging, producing very high resolution (i.e. milliarcsecond) infrared images, allowing detailed study of a variety o... |
Partially deflated helium balloon.
Why does it float where it floats? | Also, as it deflates it has less lift upwards. Totally Made up numbers: (The helium initially can lift 1lbs, 1/2 deflated it can lift .5lbs) As it settles some of the string of the balloon settles on the ground reducing the weight of the balloon + string that must be lifted by the balloon. It will settle at an equilibrium point where the weight left is equal to the weight the helium can lift.
| [
"A common helium-filled toy balloon is something familiar to many. When such a balloon is fully filled with helium, it has buoyancy—a force that opposes gravity. When a toy balloon becomes partially deflated, it often becomes neutrally buoyant and can float about the house a meter or two off the floor. In such a st... |
would what Plato spoke be at all recognisable/intelligible to a modern Greek (like how medieval English is confusing but still very recognisably English) or would it just sound like a totally foreign language at this point? | Modern Greek speakers can read aloud from ancient texts easily and can recognize many of the words. Some words will require a dictionary or extensive previous study to understand. Modern Greek also has a much less inflected grammar (similar to "church" Latin vs. classical Latin) that sometimes causes confusion for modern Greek speakers trying to parse old texts, especially in poetry where accident Greek grammar is exploited hugely for illustrative effect at the cost of intelligibility (for modern day students and possibly uneducated ancient Greeks). Greek has also undergone tons of pronunciation changes since ancient times and to the ear Plato would sound at least as bizarre to a modern Greek speaker as Chaucer would to us.
Source is my Greek classes and a modern Greek speaker who happened to be in the class. Many modern Greeks are loathe to admit to this and assume that they would be able to effortlessly communicate with the ancients, but it isn't true. A modern Greek speaker would instantly recognize that an ancient speaker was using the same language if he were paying attention but it would take a ton of effort and a little luck to get any actual communication done. | [
"The following is a list of the speakers found in the dialogues traditionally ascribed to Plato, including extensively quoted, indirect and conjured speakers. Dialogues, as well as Platonic \"Epistles\" and \"Epigrams\", in which these individuals appear dramatically but do not speak are listed separately.\n",
"S... |
How exactly does Naegleria fowleri attack the brain / nervous system and why is it so difficult to fight against? | It's nearly always fatal, but it's very rarely contracted (~3 cases per year in the US). There are many other diseases that kill many more people, and would be better candidates to spend effort and money on finding treatments for. | [
"Although the net effect of the proinflammatory mediators is to kill infectious organisms and infected cells as well as to stimulate the production of molecules that amplify the mounting response to damage, it is also evident that in a nonregenerating organ such as the brain, a dysregulated innate immune response w... |
Neglecting temperature and "space suits", could waves on Titan be surfed? | One problem would be that the oceans consist of liquid hydrocarbons like ethane and methane and those have a much lower [viscosity](_URL_0_) than water (factor 10 orso). Density is also about 50% lower, which would make it hard to stay afloat. Furthermore I assume the surface tension would be significantly lower, although I don't know if and how that affects surfing.
All these problems aside, I don't see a particular reason surfing there would be impossible, but it would be quite a different experience. | [
"Any waves on the lake are also far smaller than those that would be on a sizable body of liquid water on Earth; their estimated maximum height was less than 3 mm during observations of a radar specular reflection during \"Cassini\"'s T49 flyover of July 2009. On Titan, waves can be generated at lower wind speeds t... |
how was the iss assembled? and how are repairs and maintenance performed in the event of a collision with space debris? | The ISS was assembled by flying it to space in pieces and assembling it later with robot arms. The solar Panels were just unfolded like a piece of paper by motors. Repairs are done by performing a spacewalk if necessary. Some maintenance can be done from the inside. In some cases the damage to parts is accounted for in beforehand so you only need maintenance very rarely. | [
"On 12 March 2009, a piece of debris from the upper stage of a Delta II rocket used to launch a GPS satellite in 1993, passed close to the ISS. The Expedition 18 crew prepared to evacuate the ISS by closing hatches between modules, and boarding the Soyuz spacecraft that was docked to provide emergency crew escape. ... |
if uv light is outside the visible spectrum, how come we see the light emitted off a black light? | Blacklights work via a filter that specifically filters out visible light and allows UV radiation to pass through.
But they're not perfect, so some visible light gets through the filter and provides that purplish color you see (Because the filters are purple) | [
"UV filters are used to block invisible ultraviolet light, to which most photographic sensors and film are at least slightly sensitive. The UV is typically recorded as if it were blue light, so this non-human UV sensitivity can result in an unwanted exaggeration of the bluish tint of atmospheric haze or, even more ... |
Do flamethrowers from WW2 explode when shot? | Flamethrower operators didn't face a fiery, explosive death if their weapon was hit as depicted in films like *Saving Private Ryan* or *Hacksaw Ridge*, but could be easily injured or killed by other means.
The U.S [M2-2 flamethrower](_URL_0_), was a common model in use by mid-1944. It incorporated technological improvements over the preceding M1, introduced in winter 1942 and spring 1943, and the M1A1, introduced in the spring and summer of 1943. It consisted of several parts;
* Two long, cylindrical fuel tanks, mounted side by side, holding a total of four gallons of fuel. The M2-2, when compared to the M1, was capable of firing a normal fuel (such as gasoline or light fuel oil) or fuel mixed with a standardized thickener. The stream of un-thickened fuel as it left the gun was a wide spray. The stream of thickened fuel was much narrower, and could be "bounced" off walls, apertures, and such to get it into pillboxes, and had a habit of "sticking" to what it hit.
* A smaller, pressurized tank holding non-flammable nitrogen gas or air mounted on top of the two fuel tanks. The M2-2 improved the connection methods and quickened the changing procedure of the three tanks over the M1 and M1A1, limiting leakage.
* A valve, which was opened to release the gas stored in the pressurized tank. On the M1 and M1A1 flamethrowers, the valve needed to be opened by the flamethrower operator's assistant, while on the M2-2, the operator could do it himself as it was made to be within his reach. The valve made a loud hissing sound as it released nitrogen or air, and it was advised to not open it until within shooting range of the enemy, if possible.
* A hose, which connected the pressurized tank to the fuel tanks and allowed the pressurized nitrogen or air to enter them when the operator was ready to fire.
* Another hose, which connected the three tanks to a gun assembly held by the operator
* A gun assembly, which, when its trigger was pulled, allowed the pressurized fuel-air mixture to exit, ignited it, and directed it towards the target. The gun contained five small incendiary charges in its muzzle which were ignited and burned vigorously for a time when the trigger was pulled; the heat of the charge ignited the pressurized fuel-air mixture as it passed it. There were five charges carried in the muzzle of the gun; when they ran out, they needed to be replaced before the flamethrower could fire again.
The entire assembly of tanks, hoses, and valves was mounted to a padded packboard-like structure with shoulder straps and a belt which allowed the flamethrower to be carried on the operator's back. The M2-2 was capable of firing bursts of flame that lasted for a total of eight to nine seconds before the pressurized tank ran out of nitrogen or air and needed to be recharged. The M2-2, in comparison to the M1 and M1A1, had an increased range (twenty to forty yards, versus fifteen yards). As noted above, the new M2-2 fixed many issued that plagued the M1 and M1A1, but it still had issues of its own. if the filled pressurized tanks were left in direct sunlight, the pressure could increase and the safety discs would blow out. Heat was generated when the pressurized tank was filled, and purposefully cooling it could lead to a marked decrease (200 psi) in the pressure of the contents. Stocks of the M2-2 were also not sufficient to replace the M1 and M1A1 completely by the end of the war.
The flamethrower operator was not usually in any real danger if his weapon was hit. The fuel-air mixture did not have a surefire method of ignition unless the trigger was pulled and the mixture reached the ignition charge at the muzzle of the gun. Nitrogen and air are basically not flammable when hit by normal bullets. If the tank was hit, the filling would just hiss out harmlessly. The only danger the operator would face if his pressurized tank was compromised would be if it somehow burst like when an aerosol can is heated or punctured; he could be hit and injured or even killed by pieces of shrapnel from the exploding tank. If the fuel cylinders were hit by a normal bullet, the mixture would just harmlessly leak out; incendiary bullets posed a bit more danger. In either case, the weapon would be disabled, and would need to be returned to the Chemical Warfare Service (CWS) for refurbishment or scrapping if damaged badly enough.
Flamethrower operators often faced a unique danger in that they proved a tempting target, and were often specially tagged for quick elimination by the enemy, who feared a fiery death. The flamethrower had a very short range when compared to small-arms fire, and this necessitated that the operator get uncomfortably close to the enemy in order to eliminate him.
Flamethrowers first saw wide use in the Pacific Theater. In December 1942, small numbers of the experimental E1 and E1R1 flamethrowers were used in the southwest Pacific area, on New Guinea. The experimental models performed poorly, and improved models were not used again in the area until December 1943, on New Britain and the Admiralty Islands. The flamethrower proved itself, and was used often in campaigns until the end of the war.
The flamethrower was initially more effective and used more widely by troops in the central Pacific area. In October 1943, 12 flamethrowers were allocated to each Army infantry regiment (36 total for the division). This was soon after increased to 60, but this temporarily disrupted the supply and it took a while to achieve this level. After lessons learned in the Gilbert and Marshall Islands campaign of late 1943 and early 1944, 192 flamethrowers were authorized per division. As this was realized by the Army to be too many for one division to effectively use, the allotment was reduced to 141 before the Mariana and Palau Islands campaign of summer 1944. The E-series table of organization and equipment for a Marine division used from April 1943 to May 1944 only had 24 flamethrowers. For the Gilbert and Marshall Islands campaign, this allotment was temporarily increased to 72, and then to 81. The F-series TO & E, implemented in May 1944, fixed that problem permanently, with 243 man-portable flamethrowers allotted to the division, along with 24 E4-5 flamethrowers designed to be mounted in the bow machine gun sockets of the division's organic medium tanks! The G-series TO & E introduced in early 1945 reduced the number of man-portable flamethrowers to 108.
In comparison to the Pacific, flamethrower use was uncommon in the European and Mediterranean theaters. Flamethrowers were brought ashore in North Africa in 1942, but they were not used. They were used once on Sicily, where the 1st Infantry Division used a flamethrower to burn a field where German soldiers were hiding. The 85th Infantry Division used flamethrowers when attacking German positions around the Gustav Line in May 1944. Out of 150 flamethrowers issued by the CWS for D-Day, many were simply dumped due to their extreme weight, and about 100 were collected after the beach landing; there is not one recorded instance of them being used in action on June 6. For normal campaigning in Europe, the Army recommended that each division have 24 flamethrowers.
The flamethrower proved less effective in the ETO and MTO due to the use of open stone or brick buildings as fortifications most of the time instead of flammable wooden buildings or confined caves (which exploited the flamethrower's ability to asphyxiate enemies when the flames consumed all the oxygen in an area), and the tendency of the German, when compared to the Japanese, to surrender when outmatched or cornered instead of fighting to the death. The U.S. V Corps considered the flamethrower ineffective in the hedgerow country of the Normandy campaign. It was used successfully at Brest on a couple (the 8th Infantry Division used them three times, the 2nd twice, and the 29th at least once) occasions;
> On one occasion the 1st Battalion, 121st Infantry, 8th Division, was held up...by a series of three concrete positions....Although artillery had failed to reduce the strongpoint, it had left many large shell holes in the vicinity. Using the cover afforded...two flame thrower operators, covered by the small arms fire of ten men, were able to crawl within thirty yards of the fortifications. A short burst of flame...resulted in the hasty surrender of the occupants.
Flamethrower use was relatively sparse for the rest of the campaigns. The 1st, 4th, 9th, 30th, and 100th Infantry Divisions used them in a very limited fashion during their assaults on the Siegfried and Maginot Lines during the fall of 1944 and winter of 1945. Out of the 8 infantry divisions assigned to the U.S. Seventh Army in February 1945, 2 divisions had no flamethrowers, 1 division had 4, 3 divisions had 6, and 2 other divisions had totals of 12 and 34. Unlike in the Pacific, flamethrowers were not readily provided to infantry divisions, and division chemical officers had to purposefully seek them out, consulting engineer combat battalions (who were more likely to get them) or going to the CWS directly. A persistent problem was training; many units lacked the time or motivation to train flamethrower operators. In the U.S. Seventh Army, 80 percent of received flamethrowers were unusable in October 1944 because of a lack of batteries and ignition assemblies!
**Sources:**
* Kleber, Brooks E., Dale Birdsell. *The United States Army in World War II, The Technical Services; The Chemical Warfare Service: Chemicals in Combat*. Washington; United States Army Center of Military History, 1990.
* United States. War Department. *War Department Technical Manual 3-376A Portable Flame Thrower M2-2*. Washington; War Department, 1944.
* Zaloga, Steven J. *U.S. Flamethrower Tanks of World War II*. Oxford; Osprey Publishing, 2013. | [
"In fighting a fire at a directly vertical spewing wellhead, high explosives, such as dynamite were used to create a blast wave that pushes the burning fuel and local atmospheric oxygen away from the well. (This is a similar principle to blowing out a candle.) The flame is removed and the fuel can continue to spill... |
What was General Franco's policy towards ethnic minorities? | Franco's policy towards ethnic minorities was heavy suppression of regional identity in favor of national Castilian("Spanish") culture and language. Basque, Catalan, and Galician language and culture all faced discrimination. There were definitely attempts to hispanicize the nation, which was only natural considering Franco was far right wing with fascist ties.
Interestingly, Franco was from Galicia, a minority region in northwestern Spain, and knew the Galician(close to Portuguese) language.
_URL_1_
_URL_0_
| [
"With Franco's victory imminent, a National Council of Defense was established to negotiate a peace settlement with the Nationalists. By this point, Franco effectively had military control of the whole country.\n",
"Franco's initial coalition included monarchists, conservative Republicans, Falange Española member... |
why do i transpose words while speaking? | Language production is very complicated, and because the brain *evolved* rather than being designed by an engineer, there isn't a single "language centre" in the brain. Instead, different parts of the brain have to work together to produce speech, so one part might be retrieving the nouns you need, another part is taking care of adding other parts of speech and arranging them into sentences, and so on. Then all that information has to passed to all the different parts of the brain controlling the vocal cords, the tongue, the jaw, the lips, the epiglottis and the lungs, and the whole business timed to split-second accuracy.
It doesn't always work perfectly. All things considered, it's pretty amazing it works at all. You're just experiencing slight glitches in how your brain assembles sentences -- in the two examples you provide, the grammar is actually faultless, it just doesn't say what you mean it to say. Some people have a more serious problem, and can't effectively communicate at all: this is aphasia, and is often caused by brain damage. Depending on exactly where the problem is, there are different kinds of aphasia.
You may remember the case of Serene Branson, the [reporter who started talking gibberish](_URL_0_). That was actually a temporary form of aphasia caused by the onset of a migraine; although she knew what she wanted to say, and although all the sounds she was making were normal sounds in American English speech, the part of the brain that would normally have selected the correct sounds for the words she wanted to say wasn't working properly. Everything else, though, was: she knew what she wanted to say, and she could understand what people were saying to her.
That just illustrates how difficult and complex language production is. Just a change in the way blood flows through the brain can cause a person to lose the power of communication completely. You can be thankful that your problem is very mild, happens only occasionally and causes no more harm than some slight embarrassment. | [
"BULLET::::1. Speech is planned in advance: speech errors like substitution and exchanges show that one does not plan his/her entire sentence before s/he speaks. Rather, their language faculty is constantly tapped during the speech production process. This is accounted for by the limitation of the working memory. I... |
how/why does a show like futurama with such an avid and wide fan base get [repeatedly] canceled? what is the logic behind it from a network standpoint? | There's two categories of shows, to be broad.
You either have shows with broad appeal and a wide audience, or a show with niche appeal, and a *guaranteed* audience. Unless you run a small cable channel or a youtube channel, you're usually aiming for broad appeal even if it typically stems from shows that are dilute tripe.
Futurama is a show with niche appeal, which means in general terms that it's audience is small. It's kind of weird, the characters aren't exactly accessible- a vulgar, alcoholic, smoking, gambling robot? Oh, that isn't going to sit well with parents- and the humor can fly over the average drooling idiot's head. So you're not going to grab every last possible viewer that wasn't already invested in show X.
This being relative to, say, The Simpsons, which featured humor that typically aimed a bit lower, more easily accessible characters, and didn't really have the weird factor once you accepted that everyone's head was shaped like a pill and yellow was a skin color.
This is also why it was Adult Swim that revived Futurama. Adult swim is the lifeblood for niche appeal animated productions, along with stoner fuel. | [
"It was announced on 2 May 2009 that the series was being cancelled after only one year on air. The reasons given by TVNZ for the cancellation were lower ratings than the previous season, decreased advertising revenue and the high cost of producing the show. Lower ratings may have resulted after reformatting of the... |
What would the ramifications have been had Tsar Bomba been an underground test? | It would have heated some rock. If close to the surface it would have released some radioactive material, if buried deeper it would have stayed contained. Things don't "penetrate[] all the way through the crust"
> What would life look like on the planet had they done this, whether with the 50 or the 100 megaton model?
It wouldn't have had any effect on life apart from seismic waves close to the explosion site and potentially a little bit of radioactive material making it to the surface there. | [
"Footage from a Soviet documentary about the Tsar Bomba is featured in \"Trinity and Beyond\", where it is referred to as the \"Russian monster bomb\". The movie states that the Tsar Bomba project broke the voluntary moratorium on nuclear tests. In fact, Soviets restarted their tests and broke the unilateral volunt... |
can some please explain differentiation to me like
i'm 5? | So you have a ball and you throw it at a tree. You might notice that instead of flying in a straight line it goes up some and then goes down some before hitting the tree, flying in a curve instead of a straight line.
Now if you slow it down a whole lot you can see that for part of it the ball is headed down and for part of it it is headed up, and the direction that the ball is pointed is changing very fast.
If you wanted to figure out exactly which way it was pointed at any moment before it hit the tree you could use a math thing called differentiation. That finds something called the derivative of the function of the curve. Big words, just call it the derivative.
Pretty much you're figuring out what it is doing in a very very short period of time.
If you draw the path that the ball went it will be a curve. You mark one point where you want to figure out what direction it is going and another one anywhere else along the curve. Then you draw a line between the two points you marked. You'll notice that the line cuts under the curve for the way the ball actually went. Move the second dot closer and closer to the first one along the curve until the line formed by the two doesn't touch the curve anywhere else. The closer you put the two points together the more accurate this will be but you can never use the exact same point twice.
On paper there is a method to figure out what it would be when you make these points infinitely close together without them ever being the same point, using techniques that a five year old shouldn't try to understand.
But for five year old level scientific research, you now have a line that is the derivative of the curve at that point.
| [
"BULLET::::- 5S – 5S is the name of a workplace organizational method that uses a list of five Japanese words which, when translated into English, start with the letter S—Sort, Set in Order, Shine, Standardize, and Sustain.\n",
"Definition 7 defines what it means for one ratio to be less than or greater than anot... |
Historians Travel | I'm a medievalist, and travel is very important for my research because it's the only way I can access some of the things I study, and the only way I can talk with others in my field.
My project focuses on archaeology in sixth century England, and (as you can imagine) almost all the artifacts on which I base my work are in British museums. There's often a lot published on the objects, and much (though not all) of this material can be gotten by my amazing interlibrary loan librarians. But some things simply don't exist outside of the UK, and I have to go there to read / study / examine them.
My project is unusual in that so much of my data is already published in some form (mostly, archaeological site reports). Some historians are lucky (or unlucky) enough to work entirely from texts that have been well edited and published (if you study, for example, Tacitus' portrayal of the Germanic barbarians, you can get most of your primary sources from any good library). But most historians rely on primary sources that aren't published - archived collections of letters, legal records, or old government documents, medieval manuscripts that have never been digitized, inscriptions that haven't been catalogued and are in some museum's basement, etc. One of my colleagues is going to be visiting several hospitals in a few months to look at 100-year-old records of some of their patients. These kinds of archival sources are basically impossible to gather without traveling, and as a consequence archival research is one of the most important parts of most historians' research processes.
Paying for this research can be tough. I spend a lot of my time writing grants. I'm a grad student, so some of this funding is from my grad school, some is from organizations (like the Medieval academy of America) that fund exciting projects by medievalist grad students. Some is from big national grants like the SSRC IDRF, the CLIR Mellon, or Fulbright. Grant writing is exhausting, is very competitive (everyone wants free money), takes a ton of time, but - when successful - makes it possible to string together enough money to get to the archives and make a project happen. I'm going to England soon for the second time for my doctoral project, and will be visiting a number of tiny archives and collections and taking many frantic notes and photos before my funding runs out and I have to come back to my teaching job in the fall. Rinse and repeat, that's the dream if you can get the institutional and financial support to make it work.
The other advantage of travel, beyond tracking down your primary sources, is networking. Most of us don't live next to the other experts in our field, and while email makes it a lot easier to stay in touch with the wider community, the best way to make contacts and stay on top of the current conversation in whatever thing you study is to travel to conferences, meet other scholars, and chat over coffee or a few beers. I can read all about Anglo-Saxon England in journals until my eyes fall out, but the articles I'm reading are already a year old by the time I get them (at best). To know what's really going on, I have to go to conferences and visit universities where my fellow scholars are working to be part of the leading edge of the conversation. This means a lot of travel (and expense), and again means lots of time spent applying for travel funding and submitting pieces of my own ongoing research so I can co tribute to the ongoing conversation.
If you land one of those elusive tenure track jobs, you get more institutional support to travel, and you qualify to apply for bigger grants that allow you to undertake further archival research, or to travel to libraries larger than that of your home institution for a semester or year of research. My supervisor just returned from a year long fellowship; it was a competitive application, and -- project was judged to be one of the more exciting to throw money at. This process of attempting to convince funding bodies to send you to libraries or archives never ends.
So, how much is travel a part of the life of a professional historian? In terms of actual time, I usually only go to one conference per semester; occasionally two and rarely more (I can't abandon my students much more than that during the semester!). I'll have spent at least five months in the UK before I've finished what will be a *minimum* of six years in grad school (more than five months, if I get lucky and win a big grant - but that's a long shot). That's not a lot in terms of days away from home. But it's more than many jobs, and more importantly it's absolutely crucial for my research and participation in the larger scholarly community. So yes, travel is a big part of the job. | [
"BULLET::::- Travel Writing: The text of most of the best known historical British travel writers, including James Boswell, William Camden, William Cobbett, Daniel Defoe, Celia Fiennes, Charles Wesley and Arthur Young. The earliest source included in the GB Historical GIS is a survey of Wales written by Giraldus Ca... |
why did all the spices of the old world come from far away? were there not spices native to western europe? | There are plenty of native European seasonings; think of oregano, basil, marjoram, thyme, rosemary, sage, garlic, lavender, parsley, carroway, cumin, anise, bay laurel, dill, horseradish, juniper, mint, mustard, saffron, tarragon.
Anyway, as to your plan, you can't make money selling something that anyone can grow in their garden. Exotic spices are profitable because they're scarce and hard to obtain. | [
"Spices were all imported from plantations in Asia and Africa, which made them expensive. From the 8th until the 15th century, the Republic of Venice had the monopoly on spice trade with the Middle East, and along with it the neighboring Italian maritime republics and city-states. The trade made the region rich. It... |
how does google photos recognize my baby pictures? | The same way it can distinguish your friends from you. Or your dog from your baby. It scans the photo and compares it to a large large pool of already identified images and decided what its most likely to be.
Big brother is watching and it’s very smart 👀 | [
"Google Photos gives users free, unlimited storage for photos up to 16 megapixels and videos up to 1080p resolution. The service automatically analyzes photos, identifying various visual features and subjects. Users can search for anything in photos, with the service returning results from three major categories: P... |
what's the difference between neutron stars, pulsars, and quasars? | Neutron stars are older stars that have collapsed in on themselves, and now the only thing keeping them from turning into a black hole is the [pressure that neutrons exert](_URL_0_) because they don't like to be squashed into the same place.
Pulsars are a type of neutron star spinning very fast in which a beam of radiation is emitted from its magnetic poles. If the magnetic pole is off from the geographic pole (the axis of rotation) it will cause the star to appear to pulsate from certain angles (Imagine a giant laser coming from the north geomagnetic pole in Canada, it would appear to aliens far away that earth was emitting laser late at 24 hour intervals).
A further subtype of pulsar are [magnetars](_URL_1_) which are likely very young pulsars, and are named for their ridiculously strong magnetic fields, strong enough to rip the iron from your blood at a million miles away.
Quasars are a different creature altogether. They are supermassive black holes that existed in the early Universe. We can only see them now because some of them are so far away that their light has only just reached us. They tore through a literally unimaginable amount of material every second, so quickly and with such force that the gas and plasma around it glowed trillions of times brighter than our Sun. | [
"A pulsar (from \"pulse\" and \"-ar\" as in quasar) is a highly magnetized rotating neutron star or white dwarf that emits a beam of electromagnetic radiation. This radiation can be observed only when the beam of emission is pointing toward Earth (much like the way a lighthouse can be seen only when the light is po... |
why do cats ears twitch after being slightly touched? | Dog's ears do this too, and I think it's a reflex meant to protect the ears. In nature, if something touches your ears, it means one of two things:
1. It's harmless. It doesn't matter what you do.
2. The thing that just touched your ear is about to rip it off your skull.
Since losing the ear is a huge cost and the reflex has almost no cost at all, having the reflex makes perfect sense. | [
"Cats can change the position of their ears very quickly, in a continuum from erect when the cat is alert and focused, slightly relaxed when the cat is calm, and flattened against the head when extremely defensive or aggressive.\n",
"Purring or a soft buzz, can mean that the cat is content or possibly that they a... |
Are there any good sources that an average person could use to learn about Celtic and Gallic religions prior to Christianization? | \- *The Celtic Gauls: Gods, Rites and Sanctuaries*; Jean-Louis Brunaux; 1988.
This a study of Gaulish religious features, in their public and ritual aspects, but also how they might have conceived their spiritual universe and their Gods; but also the relation religion had with society, particularly warfare and druidism (taken the author as not as much a religion than a mix of philosophy and theology).
The comparison with Mediterranean peoples and especially ancient Greeks provides with an interesting perspective of the author, who stresses a Mediterranean aspect of Gaulish civilization. The author wrote more books about religion and philosophy in Gaul, which are benefiting from linguistic and archaeologic data from the last decades, but they are in French.
(Eventually, being able to read French, as recent secondary sources on the topic of Gaulish religion in particular can be left untranslated more often than not, might be useful)
\- *Gods of the Celts*; Miranda Green; 1986 (reed. 2016)
It's definitively a different, and arguably opposite, perspective on Celtic religion there : religion being untouched by Mediterranean influences, Celtic gods being only partly romanized after the conquest. Developments on animism and especially the consideration of Celtic religious and spiritual aspects outside Gaul (especially in Roman Britain and medieval Welsh and Irish sources) does interestingly covers a more broad "panCeltic" vision with Druids as priests. | [
"Literary evidence for Celtic religion also comes from sources written in Ireland and Wales during the Middle Ages, a period when traditional Celtic religious practices had become extinct and had long been replaced by Christianity. The evidence from Ireland has been recognised as better than that from Wales, being ... |
life on earth has existed for millions of years, growing and adapting. so why do small amounts of exposure to the sun still harm its organisms? | Your premise is false. Small amounts of exposure to the sun usually do *not* harm organisms.
The exceptions are organisms that have evolved to live in non-sunny locations. | [
"In billion-year timescales, it is predicted that plant, and therefore animal, life on land will die off altogether, since by that time most of the remaining carbon in the atmosphere will be sequestered underground, and natural releases of by radioactivity-driven tectonic activity will have continued to slow down. ... |
Has there ever been controversy arize from the translation of Holy books into different Vernacular Languages? | There are many, many disputes over this sort of thing, and that's why you find so many different translations of the Bible in English alone. Every version of the Bible pretty much exists because someone didn't like a translation which already existed. The act of translation is itself an act of interpretation, and that is a simple fact which cannot be avoided. This is all in addition to the fact that the translations themselves come from a manuscript tradition and manuscripts never agree 100%, so even if you could read the original Greek or Hebrew text, there is still the need for an editorial process to come to a single text, though the best versions will at least provide the other popular possibilities in footnotes.
As for specific examples, there is a movement which holds that the King James Bible is the only [valid bible](_URL_0_). | [
"There have been various debates concerning the proper family of biblical manuscripts and translation techniques that should be used to translate the Bible into other languages. Biblical translation has been employed since the first translations were made from the Hebrew Bible (Biblical Hebrew and Biblical Aramaic)... |
why do capacitors in crt tvs from 50 years ago still work, but every lcd i've had blew a capacitor in less than 5 years? | people like to parrot *planned obsolescence* but there is a much simpler explanation that does not require the assumption of any malice on the part of manufacturers.
it is just cheaper to make and more profitable to sell a product which works exactly as long as it is warrantied for and not much longer. the buyer is promised a certain expectation and the seller meets it. if the product exceeds the specified life, it is over engineered and the next round of cost cutting in the manufacturing process will identify and eliminate the expensive step (I.e. capacitors , or any other part for that matter, will be iterated down the quality hierarchy until the product fails minimum lifetime requirements). over years and decades of design and engineering the build quality settles to the minimum demanded by the market. in is an art that separates the small players from the industry juggernauts.
that's right. it takes two hands to clap. TVs don't last 20 years because no one is willing to pay for one that does. besides, they are going to upgrade in a few yrs time anyway and the old one is going to the landfill so it better be cheap. people want the latest tech bells and whistles which come along every 1-2 yrs (any electronic devices come to mind?) at an affordable price . incidentally, that's how long things tend to last. because neither buyer nor seller really needs it to last. | [
"Once the capacitors will become unavailable, or the current stocks become too old to be used due to deterioration, alternatives will have to be found. The Black Gate was very affordable when comparing it to some other similar-performing capacitors, and was easily available.\n",
"From 2001 to 2004, Nichicon produ... |
how do dogs always manage to shed when it's getting warmer? | They are responding to the change in the length of the day associated with the passing seasons.
EDIT: Because climate change does not affect the length of the day, it will not affect this. | [
"Dogs are even more susceptible than humans to heat stroke in cars, as they cannot produce whole-body sweat to cool themselves. Leaving the dog at home with plenty of water on hot days is recommended instead, or, if a dog must be brought along, it can be tied up in the shade outside the destination and provided wit... |
When you fart, the gas released is lighter than the surrounding air, indicating bouancy. Does this mean that we weigh nominally more after farting since we no longer have a gas inside our body that is slightly lighter than air? | Sadly, I have calculated this before. Here are my results.You do in fact gain weight when you fart, and here is the math to prove it!
Average mass of a fart: .0371 g
Average volume of fart: 35-90 ml
Ambient temperature: 20 degrees
Colon temperature: 40 degrees
Air density at 20 degrees: 8.273lb/ft3
Air density at 40 degrees: 7.942lb/ft3
Conversion factors:
1 ft3 = 28316.8 ml
1g = .00220462 lb
**Weight reduction due to Air Density change:**
(8.723-7.942)/28316.8*35
= 4.091 e-4 lb
**Weight reduction due to mass lass:**
.0371 * .0022062 = 8.179 e-5 lb
Since the air temp provides more lift while inside your colon than the mass expelled when you fart, you do in fact **gain 3.273 e-4 lb** on average when you fart.
**edit:** Someone mentioned higher pressure inside colon so here is result with that taken into account. I just found that a value for pressure in the intestine that would cause extreme discomfort is about 860 Torr or 1.13157895 atm which mean we get a slightly lower buoyancy of 3.615e-4. Turns out even taking pressure into account you still gain weight of **2.797e-4 lb or .127g**. | [
"Since a collection of gas molecules may be moving at a wide range of velocities, there will always be some fast enough to produce a slow leakage of gas into space. Lighter molecules move faster than heavier ones with the same thermal kinetic energy, and so gases of low molecular weight are lost more rapidly than t... |
just say.. we had the technology to lasso mars and bring it to same position earth is to the sun, would mars eventually be habitable like earth is today? | No. In fact, it probably would make Mars *less* habitable. The lower gravity of Mars, combined with its lack of a magnetosphere means that any atmosphere is doomed to be blown away by solar winds. Bringing Mars closer to the Sun would simply subject it to higher intensity winds, stripping away the atmosphere at an increased rate.
There is more to habitability than distance from the sun. | [
"Sagan also visualized making Mars habitable for human life in \"Planetary Engineering on Mars\" (1973), an article published in the journal \"Icarus\". Three years later, NASA addressed the issue of planetary engineering officially in a study, but used the term \"planetary ecosynthesis\" instead. The study conclud... |
Does alcohol affect insects the same as humans? | Surprisingly, yes! Ethanol vapour tested on *Drosophila* showed that they behave in an [inebriated](_URL_0_) fashion, and they have noted the activity of a gene that codes for a neuropeptide that is involved in a cAMP pathway that has an effect on various brain functions. Whether this method of ethanol inebriation affects other insects is not well researched, however. | [
"The behavior of honey bees intoxicated by ethanol is being studied by scientists at The Ohio State University, Oklahoma State University, University of Ljubljana in Slovenia, and other sites as a potential model of the effects of alcohol on humans. At the Oklahoma State University, for example, Abramson's research... |
What causes pruney fingers? | Two portions of your skin, the epidermis and dermis, are tied down to one another in certain areas. As you spend a lot of time in the pool, your skin absorbs water and expands. However, since the two layers are connected, your skin has nowhere to go, so it wrinkles. Once you're out of the pool, the water in your skin eventually evaporates and it returns to normal. | [
"Sometimes a callus occurs where there is no rubbing or pressure. These hyperkeratoses can have a variety of causes. Some toxic materials, such as arsenic, can cause thick palms and soles. Some diseases, such as syphilis, can cause thickening of the palms and soles as well as pinpoint hyperkeratoses. There is a ben... |
how does a galaxy s4 cellphone cost $450 when a decent laptop costs $300? | It's for the same reason a decent laptop costs $300 and a desktop with those same specs costs $200. Miniaturization is *expensive*. You not only have to figure out how to cram all of those same components in a smaller space, but you now also have to deal with heat dissipation. And in the case of a phone, you can't really have a cooling fan so you need to find a way to use less energy while also having both cellular and wifi transmitter/receivers. Additionally, phones have touchscreens, which are a fairly expensive component as well. | [
"The S4 sold 4 million in 4 days and 10 million in 27 days making it the then fastest selling smartphone in Samsung's history (this has been eclipsed by the Galaxy S5). The Galaxy S III sold 4 million units in 21 days, the Galaxy S II took 55 days and the Galaxy S took 85 days.\n",
"The Samsung N130 is a subnoteb... |
why isn't japan popular for esports? | I just did an essay on this exact topic actually.
There are a few reasons.
1. As others have stated, PC gaming is not popular in Japan, for various reasons. They tend to lean towards smartphones and consoles (if you call them that) such as the Nintendo DS. Often this is because of the structure of esports games, for League of Legends for example, when you press play, you have to sit there and play for 40 minutes, until the game ends, and usually you wouldn't just play 1 game in one sitting, maybe you would play 3 or 4. This is a damn long time, considering it takes many games to actually achieve a decent level of skill at the game. People in Japan prefer to play games on the train, after finishing homework, and so on. You have to remember that the typical Japanese child and Japanese businessman typically has less free time than their Western counterparts. Afterschool classes are common. Japanese businessmen are often expected to go out to dinner or drinking with their workmates after work. As a result of this, a game that you would usually sit down and play for maybe 3 or 4 hours simply doesn't fit well into their lifestyle.
2. Japanese gamers prefer to play games that are made in Japan, and their video game industry is extremely good at keeping the Japanese video game market this way. The highest selling games in Japan are games like Mario, Pokemon, Final Fantasy, Monster Hunter etc etc. Apart from a few notable exceptions, these games tend to follow a certain format. Either a) there is a famous, lead character (Mario) or b) you collect monsters and battle / trade with them (Pokemon, Monster Hunter). But the best selling games in America? GTA, Call of Duty, Assassins Creed etc. You can clearly see a difference in the style of game that is popular among gamers in both societies. Popular Western games tend to have a more "mature" theme.
3. The way Japanese society is set up, taking a year (or 2 or 3) off of study to be a professional gamer is often a massive risk. Good universities are competitive, and things such as gap years are uncommon among students. On top of this, they don't have the esports structure that Korea has.
One thing that is important to note about Korea and China, the reason they have big esports scenes is because they heavily imported video gaming from the West. Japanese video game imports were banned, so their video game scene, without a strong basis for their own industry, was heavily influenced by the West. When video games first started becoming popular, the two biggest markets were America and Japan. Japan has stayed quite reclusive, America has branched into esports, and together with Korea and China (well the strength of China and Korea in esports is another topic) has made it into a huge industry. | [
"Leaders in Japan are becoming involved to help bring esports to the 2020 Summer Olympics and beyond, given the country's reputation as a major video game industry center. Esports in Japan had not flourished due to the country's anti-gambling laws that also prevent paid professional gaming tournaments, but there we... |
What happens to a mosquito when it sucks a diabetics blood? | *Arbovirologist here.
It wouldn't matter very much at all. Both male and female mosquitoes eat sugar from any source they can find (eg: rotten fruit, nectar, etc...), but only the females take blood meals. The protein in the blood is required to produce eggs, and would still be present in large amounts even if a person was hypoglycemic. I suppose the only thing that could possibly happen is that the mosquito would have to find another sugar meal more quickly than if there were an abundance of glucose in the blood. | [
"Prior to and during blood feeding, blood-sucking mosquitoes inject saliva into the bodies of their source(s) of blood. This saliva serves as an anticoagulant; without it the female mosquito's proboscis might become clogged with blood clots. The saliva also is the main route by which mosquito physiology offers pass... |
Historical post-modernism/ post-structuralism? | Postmodernism *is* kind of vague and unspecified unfortunately. Postmodernism, or, The Cultural Logic of Late Capitalism by Frederick Jameson is kind of long and disjointed, I came out of it with a pretty good understanding of postmodernism, but there is still no solid, easy definition.
It's important to understand the world that postmodernism came from (which it seems like you do, but for the sake of this answer I'm just going to reiterate). Modernism was defined by a sort of overarching sense of optimism that came from all of the innovation going on in the early 20th century-- Socialism promised a brighter future and celebrated the power of the everyman, advances in technology were making the impossible now possible, overall things were seeming pretty new and exciting. What happened around mid-century is that people realized that some of these things weren't so great, that socialism had bred dictatorships, that the miracles of industry were destroying the environment, that modernism had no answer for repressed minorities. This disillusionment was the spark that ignited postmodernism, but from there it went many, many different directions. Here are some of the more easily defined points that Jameson makes:
• Modernism looked at newness as a movement, postmodernism looks at newness in the events, breaks, shifts, variations
• Postmodernism either expresses or represses some kind of historical urge, in a world that is deaf to history.
• Postmodernism seizes uncertainty and the disappearance of master narratives.
• Postmodernism is not a style but a cultural dominant, which allows for conflicting ideas and definitions.
• Basically all features of postmodernism can be found in modernism.
• Although it was made to scandalize, postmodernism no longer shocks us so it can be argued that it's just like modernism now.
This probably brings about more questions than answers, but maybe it kind of gives you a starting point towards understanding postmodernism. He goes into some other stuff about how economics and government systems have influenced the development of postmodernism as well, but I wouldn't feel competent to condense that argument. I've read a few essays on postmodernism and tend to like this one best because it plays in the ambiguity and allows understanding to form out of it. The Liz Wells postmodernism piece is shorter but I feel like it tries to look too closely at examples and it's hard to find the overarching movement. | [
"Modernism is the European cultural trend that marks the end of the 19th and the early 20th century. It includes all the arts and, at the same time, represents a way of life. Combining the great Catalan building tradition with sculpture, fine crafts and applied arts, in addition to using iron as a new structural el... |
why do people still believe in god? | > Don't post to argue a point of view.
This post has been removed. You want /r/changemyview. Or you want to survey people in which case you want a sub that allows that. | [
"I cannot understand why we idle discussing religion. If we are honest—and scientists have to be—we must admit that religion is a jumble of false assertions, with no basis in reality. The very idea of God is a product of the human imagination. It is quite understandable why primitive people, who were so much more e... |
Does the earth have other satellites other than the moon? | Sort of. I believe there are four known natural bodies other than the moon (none of the names of which I can remember off the top of my head, sorry) which are gravitationally bound to the Earth, but they move in complex heliocentric orbits that are quite different from what you're probably thinking of.
I think they're all in unstable resonance configurations, though, so whether you call them "satellites" or not is really a matter of personal taste … and probably also the bureaucratic whim of some standards body or something.
Pluto is so a planet. Shut up. | [
"Earth's Moon is an astronomical body that orbits the planet and acts as its only permanent natural satellite. It is the fifth-largest satellite in the Solar System, and the largest among planetary satellites relative to the size of the planet that it orbits (its primary). The Moon is, after Jupiter's satellite Io,... |
Can you point me towards some good introductory reading on Norman culture and history? | Not really my field so I can't recommend more than this, but I thought David Crouch's *The Normans: The History of a Dynasty* was a very good political history. | [
"Written in the Norman language, it consists of 14,866 lines. It was intended for a Norman audience interested in the legends and history of the new territories of the Anglo-Norman realm, covering the story of King Arthur and taking the history of Britain all the way back to the mythical Brutus of Troy.\n",
"Norm... |
why do deli meats like turkey and roast beef taste so much different when thickly sliced vs. thinly sliced? | The more surface area to mass, the more air hits it. The more air "mixed" with the product, the better the taste. Hence the slurping when tasting wine "properly".
Edit: Clarification
Correction: *more* surface area to mass | [
"It is considered a more flavorful cut than other steaks, such as the fillet, due to the muscle being exercised by the animal during its life. Its marbling of fat makes this suitable for slow roasting or grilling cooked to different degrees of doneness. Marbling also increases tenderness, which plays a key role in ... |
why does us congress block the creation of a searchable gun registry? | Many think they guard their freedom by having a secret weapons cache. If TSHTF they will have an arsenal to restore democracy, or set up their own little gang turf.
If their weapons cache was public knowledge they would be targeted by, (criminals looking for guns, the communist invaders, sort of outdated now, the IRS looking for the wealth they wasted on weapons, How did they earn it? Did they report the earnings?, ) A data base is a search. We are protected against unreasonable searches. | [
"A gun registry is a government list of firearms and their owners. Currently, in the U.S., there is no national gun registry, but some states, such as Hawaii, have provided the federal government with information on gun owners. At the federal level, legislation has been introduced to criminalize creation of a gun r... |
Are we just as capable of eating raw meats today as we were thousands of years ago? | Yes, as you mentioned, the main concern with eating raw meats is disease and infection.
Our digestive system is perfectly able to digest raw meat, it just takes a bit longer to break it down. | [
"BULLET::::- – meat is animal flesh that is eaten as food. Humans are omnivorous, and have hunted and killed animals for meat since prehistoric times. The advent of civilization allowed the domestication of animals such as chickens, sheep, pigs and cattle, and eventually their use in meat production on an industria... |
why can't i feel the digestion? | The primary purpose of perceiving stimuli is for you to respond to it in some way. There really is no point in "feeling" your digestive process, so there is no reason your brain would process that as at feeling for you to perceive. We do this for our other senses to. For example, right now your nose is in your field of vision, you are tasting your mouth, and you are probably smelling a number of things. But you don't actively perceive these things (unless you are deliberately doing so) because they're basically just background "noise." There is no utility in always being conscious of your nose, the taste of your mouth, etc.
That said, when there is something for you to respond to, your body makes that abundantly clear: for example, indigestion, heartburn, gas, or anything else out of the ordinary. | [
"The digestive system can respond to external stimuli, such as the sight or smell of food, and cause physiological changes before the food ever enters the body. This reflex is known as the cephalic phase of digestion. The sight and smell of food are strong enough stimuli to cause salivation, gastric and pancreatic ... |
why bipartisanship has seemed to disappear in american politics | Since about the 80s, the Republican party has been shifting to the far right, the loon right. That really began in earnest in the 90s, when the neocons started to grab power, and that was about the last time there was any amount of compromise in politics. Before then, Republicans and Democrats might spend all day impugning each other's ancestry on the floor of Congress, but after hours, they'd get together over drinks and horse trade, and things got done.
The "election" of Dubya was a turning point. The neocons were now firmly in charge, and began to tear down the scaffolding of compromise in favor of "our way or nothing." It is traditional for a newly-elected President to give a speech saying "the time for politics is over and now we must all work together, blah blah," but Dubya changed that. He said he was happy to work with anyone *who supported his policies.* He was publicly announcing that he was ONLY the President of those who had voted for him, and everyone else could go screw themselves.
All during the Bush administration, the Republicans shifted further and further to the right. Eventually, the Koch brothers created the Tea Party as a berserker for the Republicans, a group that could go around and smash shit up, but still leave the Republican party with plausible deniability. Of course, it got out of their control, and eventually muscled aside the neocons.
By the time Obama was elected, non-cooperation was the official party policy. Republican leaders said things publicly like their MAIN priority was to ensure Obama was a one-term president. If they had to drag the country down in flames to accomplish that, so be it.
When they shut the government down the first time, there was still enough of the old power structure in place to fix it. Nobody much cared when the shutdown was only hurting the common rabble, but when the deadline for government loan default approached, the old school stepped in and the shutdown evaporated overnight. Rich people invest in government bonds, and so a government default would inconvenience them, and we CAN'T have that, now can we? Whether there is still enough of the old guard in power now to prevent a default in a new shutdown remains to be seen. They might just drive the country right off a cliff.
And now, John Boehner has been forced out of office for being *too willing to compromise.* This is fairly horrifying, since he was pretty much the face of the Republican "our way or nothing" policy for the last several years. The notion that we might soon be looking fondly back on him as "the voice of conservative reason" should send a cold chill down your spine.
| [
"There have been periods of bipartisanship in American politics, such as when the Republicans supported legislation by Democratic President Johnson in the early 1960s, and when Democrats worked with Republican President Reagan in the 1980s. It is claimed that the non-partisanship in foreign policy was a precursor t... |
What are the different characteristics and cultural differences in the usage of the bow and arrow? | Here is an interesting article describing the concurrent use of the atlatl and the bow and arrow by Aleut peoples. Essentially, they were hunting sea mammals with atlatls and using bow and arrows for warfare/intergroup conflict.
The advantage of atlatls for hunting was that they could launch them with one hand from a kayak.
_URL_0_ | [
"BULLET::::- Bows and arrows were used by most cultures around the world at some point or another and are at least 8,000 years old. The arrow is created, similarly to a spear, from a small blade (arrow tip) attached to the one end of a wooden shaft. Attached to the other end are feathers that help stabilize the arr... |
Does early stage Prostate Cancer have any effect on one's sex drive? | Not in early stages - it's asymptomatic. Obviously when it spreads it can have effects up to death.
However, treatment often has large effects including impotence due to damage to the nerves attached to the exterior of the gland, and incontinence due to excision of a sphincter along with the gland.
After my prostatectomy at age 58 I had pretty good function, but it feels different because you don't get that glandular ache at ejac-time when the seminal fluid is produced. Now that I'm almost 74 I have difficulty maintaining an erection, but the drive (mental) is still active. | [
"In 2003, an Australian research team led by Graham Giles of The Cancer Council Australia found that males masturbating frequently had a lower probability to develop prostate cancer. Men who averaged five or more ejaculations weekly in their 20s had significantly lower risk. However they could not show a direct cau... |
why is it when we are at school the majority of tests are memory based when in the real world we can look formulas and definitions up? | First, being able to easily call to mind a particular formula or fact or whatever can be of great use. Say you're looking at a particular formula that you've come across for one thing, and it sparks your mind that it looks a lot like another formula that you've committed to memory for some related topic - that recollection could be very useful or revealing, and it certainly wouldn't have happened unless you had committed it to memory. Having these concepts at the tips of your fingers makes it much easier and faster to quickly deploy them practically in the real world. It makes it barely even conscious eventually.
A second and important consideration is that non-memory based tests are very hard to write. Often they're far too easy or far too hard. Normally tests contain a mixture of 'recall' questions that people can pick up marks on, and then stretch questions that require application of knowledge to new areas. Stretch questions are often much harder to write in a balanced way. | [
"Accuracy of memory is an important factor when studying memory in children as it has been demonstrated that children’s memory more susceptible to suggesting and implanting of false memories than adults. In a study on preschoolers, using a questionnaire method in a yes/no and multiple choice format, the result of f... |
On average, how many times a year does a regular, healthy person get sick? | You're asking a question that will become a statistical nightmare. Epidemiologists track a lot of things, but they do their best to track specifics rather than generalities, and you're asking about generalities. For example, they may track the incidence of doctor visits related to specific strains of Influenza A between October and March. They then attempt to extrapolate and guess how many people *had* Influenza A but didn't go to the doctor. They may also track doctor visits for Influenza-Like-Illnesses (ILI). But what you're asking is tracking statistics on both that take into account frequency of doctor visits, with a mess of extrapolation and assumptions that one would have to make. I just don't think it's possible to answer with any real degree of certainty. That said, I'm not an epidemiologist.
With regards to susceptibility:
* Sleep, diet, stress, exercise, etc, etc, etc. | [
"In the United States, as of 2004 nearly one in two Americans (133 million) has at least one chronic medical condition, with most subjects (58%) between the ages of 18 and 64. The number is projected to increase by more than one percent per year by 2030, resulting in an estimated chronically ill population of 171 m... |
why do calories in food not translate to fullness from eating? | Each food has a different amount of calories per volume. Your stomach volume defines when you feel full. You can fill your stomach with small high calorie food, or large low calorie food, and about 10 minutes after you fill your stomach(or get very close to full) is when you actually feel full. | [
"The 'empty calories' argument is that a diet high in added sugar will reduce consumption of foods that contain essential nutrients. One review reported that for increases in consumption of added sugars, nutrients at most risk for inadequacy were vitamins E, A, C, and magnesium. For these, nutrient intake was less ... |
Why do some metals glow red hot at their melting point (i.e. Iron, nickel, etc) while others (i.e. Aluminum) are silver when molten? | Different melting points.
At roughly around 700°C (=1292°F) the human eye notices a faint dark red glow.
Aluminum is already molten at this temperature wheras iron needs a lot more heat and is already glowing bright yellow (around 1550°C (=2822°F)) | [
"Iron or steel, when heated to above 900 °F (460 °C), glows with a red color. The color of any heated object changes predictably (due to black-body radiation) from dull red through orange and yellow to white, and can be a useful indicator of its temperature. Good quality iron or steel at and above this temperature ... |
Why didn't LBJ get sued for sexual harassment? | Ironically, sexual harassment law in the United States might not exist in its present form without LBJ. Federal sexual harassment law grew out of Title VII of the Civil Rights Act of 1964, a law that LBJ was instrumental in passing. The actual reasons for sex discrimination being included within the law are complex, but suffice to say that the law was intended to combat racial discrimination and sex discrimination was included at the last minute. Some Senators backed the sex discrimination amendment because they thought it would kill the legislation and some legitimately believed in ending sex discrimination, but enforcement powers in the area were (and are) limited. The EEOC, the primary federal power behind that section of the law, doesn't have regulatory power (they can issue advisory opinions and join lawsuits). The first sexual discrimination case (Barnes v. Train) was still a decade after the passage of that law, and sexual discrimination as we know it today didn't really develop until the 1980s.
So, no one sued him because there was no grounds for a sexual harassment suit. But the lack of a lawsuit doesn't mean that his behavior didn't come back to haunt him. LBJ's major legislative accomplishments happened in his first two years as president, and by the end of his presidency he was battered by Vietnam, civil unrest, and scandal. Caro's books on Johnson make clear that many elected officials were bothered by Johnson's personal behavior but stuck with him because of his popularity and political power; once the popularity and power were gone, he lost the support of congressional powerbrokers. | [
"On July 6, 2016, former Fox News anchor Gretchen Carlson filed a sexual harassment lawsuit against Ailes. Carlson alleged that she had been fired for rebuffing Ailes' advances. Ailes, through his attorney, Susan Estrich, denied the charges. Three days later, Gabriel Sherman reported accounts from six women (two pu... |
why does heat melt some things, but harden or cure others? | Well, everything is made of tiny molecules and these molecules are always moving around, and go faster and faster as they get hotter. When they get really fast they turn into a liquid and when they get even faster they shoot off away from the rest of the molecules and turn into a gas. Solid, liquid, and gas are the three main stages of matter, and for most material how hot they are determines what stage they are in.
The trick comes when you realize that these three phases come at different temperatures depending on the material. So clay has phyllosilicates and water, phyllosilicates are like a kind of rock, and when you have it mixed with water it's kinda like really good oatmeal, and it's like both a liquid and a solid. You can shape it around when it's like that and make whatever you want. When you heat it up the water, which is already a liquid, turns into a gas and flies away, leaving the rock in whatever form you shaped it into. The rock only turns into liquid when it gets crazy-super-hot, and the oven doesn't go up that high, so only the water evaporates and the clay is left hard. | [
"For a solid to melt, heat is required to raise its temperature to the melting point. However, further heat needs to be supplied for the melting to take place: this is called the heat of fusion, and is an example of latent heat.\n",
"This strengthening occurs because of dislocation movements and dislocation gener... |
Why doesn't neutron scattering cause fission/neutron capture? | If a neutron scatters, then by definition, it’s not participating in a reaction channel.
If you bombard a target with neutrons, there will in general be many possible channels: elastic scattering, inelastic scattering, capture, fission, (n,2n), (n,p), etc. | [
"Neutrons can elastically scatter off nuclei, causing the struck nucleus to recoil. Kinematically, a neutron can transfer more energy to a light nucleus such as hydrogen or helium than to a heavier nucleus. Detectors relying on elastic scattering are called fast neutron detectors. Recoiling nuclei can ionize and ex... |
does led burn out faster similar to how light bulb burn out faster from 'strobe lighting' them? | No. LEDs generate light differently from incandescent bulbs. They don't get nearly as hot and so they don't suffer from the damage that comes with rapid heat/cool cycles. | [
"Light-emitting diodes (LEDs) are increasingly used in automotive lamps. They offer very long service life, extreme vibration resistance, and can permit considerably shallower packaging compared to most bulb-type assemblies. LEDs also offer a potential safety benefit when employed in stop lights, because when power... |
for people that have been exposed to high level of radiation, after the initial bouts of symptoms why does it look like they seem to be in recovery but in reality are not. the next stage with the symptoms coming back worst and eventually dying? | It depends on the dose. At high enough doses, there is no latency period because your cells have been completely destroyed. At lower doses that are still fatal, what's happening is that the radiation has destroyed the DNA of cells, making them unable to replicate. These cells will continue to live for some time, but once they start dying, there's nothing to replace them. This becomes apparent as rapidly diving cells begin to die. For example, damaged bone marrow is unable to make new blood cells, which results in profound anemia, low white cell count, and low platelet count as new cells are not made to replace ones that have died. This can lead to rapid onset of major infections and uncontrollable bleeding as there are no white cells to fight infections and no platelets to clot wounds.
Cells of the gastrointestinal system also divide rapidly, so gastrointestinal symptoms are usually early and severe. As the cells that line the digestive tract die, they slough off and are expelled as vomit and diarrhea. The body is then unable to absorb any nutrients as the digestive system is essentially dead. This also allows the bacteria that live in our digestive tracts to enter our bloodstream and cause sepsis.
Essentially, it's that at certain doses, the radiation exposure isn't enough to kill cells right away but is enough to make them unable to replicate. Once they die, which can take days or weeks, the latent phase ends and profound illness begins. | [
"The amount of time between exposure to radiation and the onset of the initial symptoms may be an indicator of how much radiation was absorbed. Symptoms appear sooner with higher doses of exposure. The symptoms of radiation sickness become more serious (and the chance of survival decreases) as the dosage of radiati... |
Given the recent uptick in Jihad versus Crusade comparisons, i've seen this image a lot, what does it ACTUALLY show? | There are many problems with this comparison. Just from the top of my head, the picture is flawed for these reasons:
* The pictured compared two very different time-frames, the "Muslim" Conquest extended from 632 to the Ottoman conquests of the 17th Century, whilst the Crusades picture only covered the famous crusades to the Holy Land, not the Fourth Crusade (which conquered Constantinople and other Christian territories), the Reconquista in Spain, and the Baltic Crusades. Not exactly a fair comparison is it?
* What is the definition of a battle? We have no idea about where most of the early battles of the Arab Conquests took place, let alone their size, so the creator of this image definitely just put some random dots in likely places. Visigothic Spain for instance fell in the eighth century seemingly after just one major battle - all those battles in Spain on that map must therefore be the result of later conflicts, which cannot be just characterised as battles between Christians and Muslims, since Al-Andalus was known for its tolerance and internal divisions (though of course this is a generalisation as well).
* Likewise for Crusades map - there were way more than 13 battles, both Tunisia and Egypt were for instance attacked by Louis IX of France. There must have also been many many raids led by crusaders - if we are counting Muslim raids into France, why not the crusaders'?
* The causes of battles between Muslims and Christians were complex. The armies during the rise of Islam for instance definitely included Arab Christians and Jews in their ranks, whilst many Muslims allied with Christian powers during the later Crusades as well. Muslims and Christians did co-exist and we should never see the past as being entirely made up of conflicts or peace - it was mostly a mixture of both.
This comparison is blatantly made to make a political point, not to represent the historical reality. A look through any modern scholarship on the Arab Conquests would for instance reveal that the Conquests, as far as conquests go, were fairly mild. Sieges and massacres were rare and toleration was the norm rather than pogroms or expulsions. I know a lot less about the Crusades, but I know enough to say that they were very complex as well - reducing history to misleading pictures like this is very dangerous and ought to be refuted at every possible opportunity. | [
"Secular critics of the crusades has paralleled the Crusades with the Islamic concept of \"jihad\" as comparable approaches to a religious justification of war. The opposing position emphasizes the offensive nature of Islamic jihad as opposed to the intrinsically defensive nature of the Crusades as a project to re-... |
why can't you reuse needles on yourself? | It may not look like it but the tip gets significantly blunted the first time it penetrates the skin, and successive use of the same needle can cause scarring and damage to your veins.
Also, proteins in blood form clots when exposed to air. If you pull a needle out, any blood on/in it will coagulate. If you reuse the needle you risk injecting a small blood clot into your circulatory system which could in theory kill you if it blocks off the right blood vessel in the right spot. | [
"Proper needle technique and hygiene is important to avoid skin irritation and injection-site infections. A new, sterile needle should be used each time, as needles get duller and more damaged with each use and reusing needles increases risk of infection. Needles should not be shared between people, as this increas... |
What was the significance of the Big 3( Zeus, Posiden and Hades) in ancient Greece? | Followup question: is the term "Big Three" actually used by ancient Greeks or modern historians, or is it simply popularized by fiction writers? | [
"The Stoa of Zeus (\"Eleutherios\") at Athens, was a two-aisled stoa located in the northwest corner of the Ancient Agora of Athens. It was built c. 425 BC–410 BC for religious purposes in dedication to Zeus by the \"Eleutherios\" (\"pertaining to freedom\"): a cult founded after the Persian War. It is different fr... |
When we look exoplanets, aren't we missing the 99% of planets that don't pass directly between us and their star? | Yes. Detecting exoplanets is very difficult. With the "wobble" technique they don't have to be passing directly in front of the star; as long as the orbit isn't totally perpendicular to our line of view then we have a chance of detecting them that way. There are also some that can be [directly imaged](_URL_0_). | [
"It has 3 transiting planets seen by the \"Kepler\" space observatory in their K2 survey. As of October 2017, it is the closest star discovered to have transiting exoplanets found by either the Kepler or K2 missions. The planets (b, c, d) have radii of 1.62, 1.27, and 2.09 times that of the Earth, and periods of 1.... |
What was the Russian Empires response to the American Revolution? | I will provide you books after I come home. Russia was the first member of League of Armed Neutrality - international organization which aim was securing arms trade with American rebels. It didn't achieve anything, except the British declaration of war to Netherlands. Also, Russia recognized US in beginning of XIXth century, however I will provide exact date when I am at home
Sources:
Jack P. Greene, J. R. Pole, A Companion to the American Revolution.
Dean Burns, Frederik Logevall, Louise B. Ketz, Encyclopedia of American Foreign Policy
Harold E. Selesky, Encyclopedia of the American Revolution, under "Armed Neutrality". | [
"The Russian Empire's role in the American Revolutionary War was part of a global conflict of colonial supremacy between the Thirteen Colonies and the Kingdom of Great Britain. Prior to the onset of the war, the Russian Empire had already begun exploration along North America's west coast; and, the year following t... |
Was thick, bulletproof metal armor, like Ned Kelly used in the Glenrowan shootout in 1880, ever produced or considered by anyone before then? Why didn't it catch on? | I'm afraid I can't speak to the sixteenth and seventeenth centuries, but I can speak to the eighteenth and nineteenth.
Breastplates were worn through the eighteenth century by some nobles or leaders in situations where they could be exposed to gunfire. The famous American Revolutionary War naval hero John Paul Jones wore a breast and backplate beneath his coat as protection against small arms fire from opposing vessels (I believe it is in the collection of the Metropolitan Museum of Art in New York, but *The Collector's Illustrated Encyclopedia of the American Revolution* has a few photos). It's worth noting that few officers in the field of the same period wore breastplates. John Paul Jones was most likely to be exposed to direct fire from the enemy, as well as splintering and shrapnel, than your average field officer, and as he commanded from a fairly constrained space (a quarterdeck), he did not require the mobility that soldiers in the field would.
For the eighteenth century, the reasoning behind lack of armor was twofold: range and thickness. The furthest a standard smoothbore musket could fire with lethal force was about 100 yards, and at that extreme range weapons were very inaccurate. Most fighting took place fairly close, and required a good deal of mobility. To stop a bullet within the lethal range of smoothbore flintlock muskets required a thick and heavy metal, which was not conducive to the mobility required to maneuver in the line. At that, such armor would have been prohibitively expensive to equip for an entire army.
The same is largely true of the nineteenth century. Many editions of *Harper's Weekly* during the American Civil War carry advertisements for a "Bullet Proof Vest." These had much the same issues as those in the nineteenth century: too heavy, lack of mobility, and largely uncomfortable. At that, the penetrative strength of firearms of the period had increased dramatically. To quote a [Smithsonian blog post](_URL_0_) on the subject:
> With no oversight to ensure the reliability of manufacturers' claims, it was the soldier's prerogative as to whether or not to accept assurances that the vests had been "repeatedly and thoroughly tested." While some soldiers wore the vests into battle, others opted to first test the effectiveness of the garments themselves. Colonel Johnson, for instance, sat down one morning in May 1862 to write a letter to his wife, telling her that he and his fellow field officers were just about to test their newly arrived bullet proof vests with muskets, rifles, and pistols. He resumed his letter a few hours later, reporting that they had "just returned with the great, mighty, powerful 'bullit proof' vest and the result is that a common musket put a ball clear through it at 50 yards, through yes, and carried some four or five inches of the stuff with it." The metal and cloth fragments carried by the bullet into a man's body, he surmised, "would have killed the devil himself if it all had entered his body" (Pelka, 112-113).
In short, these were heavy, expensive, and by the nineteenth century, very ineffective pieces. | [
"In 1879, Australian bushranger and outlaw Ned Kelly devised a plan to create bulletproof armour and wear it during shootouts with the police. He and other members of the Kelly gang—Joe Byrne, Steve Hart, and brother Dan Kelly—had their own armour suits and helmets crafted from plough mouldboards, either donated by... |
how do animals in the wild know what’s safe to eat? | Some level of smell/taste (bitter for humans, for example, tends to be toxic) is in play, and probably some instinct, however many, say, dogs do occasionally eat very toxic organisms that either kill them or seriously make them ill. How much that happens in the wild is difficult to measure, but there are plenty of cases of pet dogs eating toxic mushrooms/plants. | [
"Improved conditions to minimize rodent contact with humans are the best preventive measures. Animal handlers, laboratory workers, and sanitation and sewer workers must take special precautions against exposure. Wild rodents, dead or alive, should not be touched and pets must not be allowed to ingest rodents.\n",
... |
What causes the darker and lighter portions of the moon that you can see when you look up at it? | There are 2 types of terrain on the Moon:
the lighter areas are "highlands"; they are older and consist mostly of anorthosite.
The darker areas are "maria", they are somewhat younger and consist of basalts and gabbro which flooded large impact craters after major impacts punched throught the anorthosite crust. | [
"As the phase angle of an object lit by the Sun decreases, the object's brightness rapidly increases. This is mainly due to the increased area lit, but is also partly due to the intrinsic brightness of the part that is sunlit. This is affected by such factors as the angle at which light reflected from the object is... |
what is social security, how does it work in the u.s, and why is it deemed unsustainable? | Social Security was instituted during the Great Depression to do two things. First, it was to give retired people who had lost everything in the crash income to survive. Second, it was in incentive to get many old people to retire to open jobs up for unemployed youth. So they come up with a plan to take a little bit out of everyone's paycheck, and give it to retirees so they can survive.
Fast forward 20 years and we get the Baby Boom. Now with a good economy and a TON of workers Social Security is making more money than they're paying out. So we decide to invest it like any other financially savvy person. In a rare case of actually getting out AHEAD of the problem, we realized we're going to need this money when all these Baby Boomers RETIRE. Well what do we invest it in? Has to be low risk! Low risk = US Government Debt.
Fast forward to present day, the Boomers are starting to reach Social Security age and the US Government owes Social Security an IMPERIAL SHITLOAD of money it doesn't have. So Social Security will be needing this money over the coming decades and the federal government is broke. Due to changes in birth rate and advances in medicine that couldn't have been forseen in the 1930s, there are very fewer workers now per retiree. Nobody knows where the money is going to come from to handle all the payments. | [
"Social security is \"any government system that provides monetary assistance to people with an inadequate or no income\". In the United States, this is usually called welfare or a social safety net, especially when talking about Canada and European countries.\n",
"In the United States, Social Security is the com... |
How do blind people conceptualize mathematics? (Not trying to be rude) | It is an interesting question and I would imagine you are right in thinking about using touch instead of sight. The problem with asking this question on Reddit is that I would imagine there is a very small population of blind people using a website that they can't read. You would be better asking someone who is blind.
Again if you do ask someone who is blind, "how do you conceptualise a triangle?" for example... They would probably just say something along the lines of a triangle is a triangle...
The more I think on this the more complicated it seems....
How do people that CAN see conceptualise shapes? I mean, we live in a 3 Dimensional world, how can we understand a 2 Dimensional shape? They are essentially just numbers.
Wow.... I am confused | [
"Sometimes called dyscalculia, a math disability involves difficulties such as learning math concepts (such as quantity, place value, and time), difficulty memorizing math facts, difficulty organizing numbers, and understanding how problems are organized on the page. Dyscalculics are often referred to as having poo... |
Evolution of color vision | Here is a pretty good paper on the evolution of vertebrate visual pigments
_URL_0_
The wavelengths that each cone are sensitive to are determined by the photopigments they express. Mutations in the photopigment genes can alter the sensitivities, for example a single mutation that substitutes a phenylalanine for a leucine in the 'blue' opsin gene shifts the sensitivity into the uv spectrum. The colors we see are not only a result of the genes we retained from our ancestors but the genes we have gained as well through mutation and duplication events so it isn't simply a matter of looking for the remnants. Our ancient primate ancestors only have pigments sensitive to the blue and red spectrum, however in old world monkeys a duplication event in which the red gene was copied and mutations accumulated resulted in a green sensitive (530nm) pigment giving us trichromatic color vision, but the mechanism for trichromacy in new world monkeys is different- the different pigments are just different alleles and since these genes are on the x chromosome only females heterozygous for the 2 alleles have trichromatic vision. It gets even crazier in us humans because the similarity of the red and green genes and the fact that they are present on the chromosome in a head to tail fashion means there is very regularly unequal crossover and hybrid genes formed, and depending on where the crossover occurs the sensitivities could change dramatically. I work in color vision research and have sequenced hundreds of people's opsin genes and the variation is remarkable! This and the fact that 1 in 12 men is colorblind is a great example of mutation pressure. All this crossover doesn't occur because it is advantageous- it is just a function of the structure of the gene array. Most people even have many copies of each gene! There is a ton of good information on the different types of color vision and how they evolved in pubmed. | [
"The evolution of trichromatic color vision in primates occurred as the ancestors of modern monkeys, apes, and humans switched to diurnal (daytime) activity and began consuming fruits and leaves from flowering plants.\n",
"The evolution of trichromatic color vision in primates occurred as the ancestors of modern ... |
if special relativity allows one observer to observe event a as occurring before event b and another to oberve event b as occurring before event a, how casuality can be preserved if event a caused event b? | Because *if* A caused B, then A will occur before B in all reference frames. | [
"However, in the relativistic description the \"observability of events\" is absolute: the movements of the observer do not influence whether an event passes the \"light cone\" of the observer. Notice that with the change from a Newtonian to a relativistic description, the concept of \"absolute time\" is no longer ... |
is there any way to reverse what humans have done to the earth since the industrial revolution? | Carbon moves around between various reservoirs (e.g. CO2 in the atmosphere) in what is called [the carbon cycle](_URL_0_). Humans have increased the rate at which CO2 is going into the atmosphere and decreased the rate at which it leaves, causing more to build up in the atmosphere over time.
In the absence of further human meddling the processes underlying the carbon cycle will slowly (by human standards) adjust and likely begin to bring down the amount of carbon locked up in the atmosphere/dissolved in the oceans.
On any timescale relevant to humans, though, that CO2 is there to stay. | [
"Michael Bess sees the world increasingly permeated by potent technologies in a process he calls “artificialization” which has been accelerating since the 1700s, but at a greatly accelerated rate after 1945. Over the next fifty years, this transformative process stands a good chance of turning our physical world, a... |
if a closed room has a 100w fan running inside, is the room being heated by 100w? | The answer to this depends very much on if you are asking an engineer or a physicist.
There are many types of electrical motors, efficiency varies from about 85% - 95%. Let's say 90% on average. Most of the 10% loss will be lost as heat due to electrical resistance, some other weird stuff, friction and the rest will be noise.
If you are an engineer, a closed room means closing the door on a bedroom in a real world building. In this case the heat is approximately equal to the 10% loss, except for noise, so say around 8%. So for a 100W motor that is 8W of heat.
If you are a physicist, the closed room is a perfectly sealed and perfectly insulated space. In this case the noise also becomes heat due to molecules banging into each other. But also the work of the fan eventually becomes heat too in the same way. The fan is just moving air molecules, which collide with each other and the fan blades and the wall, producing heat. So in this case a 100W fan is converting 100% of the energy into 100W of heat.
tl;dr - yes and no, depending on how spherical cows are in your universe. | [
"Some convective heaters use a fan to help circulate warm air throughout a room. Their heating elements are metal or ceramic and are in direct contact with room air, allowing fan heaters to warm a room quickly.\n",
"A fan heater, also called a forced convection heater, is a kind of convection heater that includes... |
how were medieval guilds different from labor unions? | matgopack misses one very crucial difference. A guild is run by owners of the businesses, the shops, factories, tanyards, etc. A labor union is composed of people who work at the shops, factories, tanyards, etc.
The guilds were a cooperative effort by owners to restrict competition, to keep, say, 20 cutlers from working in a town that had enough trade for 5. They demanded qualifications for the workers in those businesses: on the face of it, to keep up the quality of the goods made, but in practice to allow the favored apprentices and workers to advance in the trade and the un-favored to stay put. Fairness to workers was not the priority. To gain entry into the guild of watch makers in Geneva in the 18th., for example, an apprentice's family had to pay a master for an apprenticeship, as well as bonding their son for several years as an unpaid worker. The guilds made it impossible for someone to set up a business without first having the permission of the guild.They also were social organizations: guilds had banquets, ceremonial meetings, kept records. (Some guilds, like the Long String Bow Makers in England, had ceased to be anything but a social fraternal organization by the 18th c.) If guilds resemble anything, perhaps it's the late 19th c. business "trusts" who managed to keep tariffs high and cooperatively set prices.
A craft union in some ways also wants to restrict the market; it wants to set wage and working conditions requirements for the businesses that employ its members. But it doesn't include the businesses as members. | [
"Guilds, associations of artisans and merchants, oversee the production and distribution of a particular good. Guilds have their roots in the Roman Empire as \"collegia\" (singular: \"collegium\") Membership in these early guilds was voluntary. The Roman \"collegia\" did not survive the fall of Rome. In the early m... |
What happens to impurities in drugs when they are injected intravenously? | A piece of foreign matter in the circulatory system is called an embolus.
Emboli can arise from natural materials already within the circulation, such as blood clots, or can be introduced by injection.
What happens to an embolus is mostly determined by its size and where it arises from. Assuming it is not something that will break down or dissolve, an embolus injected into a vein will be carried by the blood flow into the right side of the heart, and then into the pulmonary artery, and into the lung. A small embolus will then impact in one of the lung capillaries and may cause minimal damage, but a large one can lodge in a larger vessel blocking off the blood flow to a substantial segment of the lung, causing a pulmonary embolus. Large pulmonary emboli can be fatal.
There are a few special situations. An air embolus occurs when a large amount of air (usually > 10mls) is injected into a vein. This can become trapped in the right ventricle of the heart, preventing the heart from effectively pumping out blood. Again, potentially fatal.
A paradoxical embolus occurs when there is an abnormal connection between the left and right sides of the heart. Instead of travelling into the lung, the embolus passes through into the left side of the heart and is pumped out into the main circulation. It can lodge in any organ, but often its the brain, where it can cause a stroke.
An amniotic fluid embolus is an extremely dangerous (and rare) complication of childbirth where fluids from around the fetus pass through the placenta into the mothers circulation during childbirth causing severe reactions. | [
"BULLET::::- Chelation: The presence of di- or trivalent cations can cause the chelation of certain drugs, making them harder to absorb. This interaction frequently occurs between drugs such as tetracycline or the fluoroquinolones and dairy products (due to the presence of Ca).\n",
"Impurities are either naturall... |
how long was a true solar day 200,000 years ago? | The day is getting slightly slower as the Earth ages, mainly due to the dissipation of tides the moon raises in the Earth's oceans. The rate at which the Earth's rotation is slowing can be modeled through the following formula, which does a good job of fitting the results of lunar range finding experiments as well as some historical data:
ΔP / Δt = 1.7 ms / day.
Assuming that the acceleration was constant (and it probably isn't), this corresponds to an average decrease of only 3.4 seconds over 200,000 years.
Edit: sorry, I meant milliseconds per century! Sorry for the confusion... | [
"The Hindu cosmological time cycles explained in the \"Surya Siddhanta\", give the average length of the sidereal year (the length of the Earth's revolution around the Sun) as 365.2563627 days, which is only 1.4 seconds longer than the modern value of 365.256363004 days. This remains the most accurate estimate for ... |
why do crabs have to be boiled alive? why can't they be killed before boiling? | [The standard method for cooking crab is to kill them first](_URL_0_). You might be thinking of Lobster, which is another thing entirely. Lobsters aren't particularly clean, and they need to be cooked immediately after death, before bacteria colonies can grow. | [
"The LLF consider boiling lobsters alive (the traditional method for cooking them) unacceptable and use direct action to prevent it. As lobsters possess a rudimentary nervous system, the LLF believe they feel pain and thus boiling them is unnecessarily cruel. This was challenged by a Norwegian study released in 200... |
How far would the moon have to be from the earth before it starts to rotate around the sun instead of the earth? | The Earth's "[hill sphere](_URL_0_)" describes its sphere of influence -- if a gravitating body is outside of this sphere, then it would orbit the Sun instead.
For the Earth, this would be 0.01 AU from the Earth, or 1.5 million km. | [
"The Moon orbits Earth in the prograde direction and completes one revolution relative to the stars in about 27.32 days (a sidereal month) and one revolution relative to the Sun in about 29.53 days (a synodic month). Earth and the Moon orbit about their barycenter (common center of mass), which lies about from Eart... |
Are the mechanisms that cause cancer mutations the same mechanisms that cause the appearance of new traits that we've evolve into? | Cancer is caused by defects in certain genes that produce tumor suppressing proteins. So when these proteins are not present, cells grow indefinitely, eventually you get cancer. Curing cancer will not have do anything to stop evolution. | [
"Several hereditary factors can increase the chance of cancer-causing mutations, including the activation of oncogenes or the inhibition of tumor suppressor genes. The functions of various onco- and tumor suppressor genes can be disrupted at different stages of tumor progression. Mutations in such genes can be used... |
in the lord of the rings, a series of large fires are used to communicate a call for urgent aid over a mountain range. is there any mention of anything like this being used throughout history? or would it have been too hard to man/ supply? | Here's a [great answer](_URL_0_) from /u/BRIStoneman that addresses your question! | [
"Operation \"Mountain Storm\" () was a military operation carried out on 7 November 2007 by special police forces of the Republic of Macedonia against an armed ethnic Albanian group in the Tetovo region with ties to Albanian paramilitary of the conflicts in Kosovo (1998–1999), Preševo Valley (2000–2001) and Macedon... |
When was the Roman title "princeps" replaced by "emperor"? | Remember that 'emperor' is an English title, which is not directly analogous to the Latin *imperator*. When we say that Augustus became the first 'emperor', we are analysing a unique, and irreversible, combination of both political offices and personal status/influence that coalesced in a single figure, who simply could not be matched within the sphere of Republican Rome.
The title *imperator* is more specifically one associated with military power, and the concept of *imperium*, the right to put to use the power of the state, primarily through the army.
In the Greek East *autokrator* was used as a translation for *imperator*, but it does not have quite the same idea.
It's fairly common to refer to the period Augustus through to Domitian as the *Principate* because Augustus preserved the title *princeps* and maintained many of the trappings of Republicanism, as did his immediate successors. While Domitian did away with a lot of them, and the increasing 'easternness' of the Empire saw adoption of stylings more familiar to the Hellenic and even Persian world - which had less hang-ups about (divine) Monarchs.
In the east emperors tended to be referred to in Greek as *basileus*, which originally meant 'king', but in the imperial period tends to only refer to the Roman emperor(s); ironically, they took the Latin word *rex* (also 'king') into Greek to refer to kings.
So, really, I am saying that there wasn't really a 'word' for 'emperor', in Latin/Greek, there was a range of titles and terms, none of which exactly overlays our 'emperor'. | [
"The Emperor Diocletian (284–305), the father of the Tetrarchy, was the first to stop referring to himself as \"princeps\" altogether, calling himself \"dominus\" (lord, master), thus dropping the pretense that emperor was not truly a monarchical office. The period when the emperors that called themselves princeps ... |
Why are some elements referred to as synthetic or artificial? | It's not necessarily impossible for these elements to be created naturally, it's just we have no indication that it's happened. Odds are, some supernova somewhere did create elements heavier than Californium, but all the synthetic elements are unstable enough that we almost certainly wouldn't be able to detect them before they decayed. | [
"A synthetic element is one of 24 chemical elements that do not occur naturally on Earth: they have been created by human manipulation of fundamental particles in a nuclear reactor or particle accelerator, or detonation of an atomic bomb; and thus are called \"synthetic\", \"artificial\", or \"man-made\". The synth... |
Wehrmacht vs SS | One thing that clouds the issue here is the “Myth of the Clean Wehrmacht” – the notion that the Wehrmacht was just fighting a war, whereas the Government and the SS were responsible for all of the war crimes. The myth was developed as a deliberate attempt to rehabilitate the Wehrmacht in order to legitimise the establishment of the Bundeswehr in the 1950s. The development of the Cold War led politicians to decide that West Germany needed armed forces to defend itself, but the establishment of these forces needed to get over the obstacle of public opinion. In 1950 the Himmelrod Memorandum was issued suggesting that the German Chancellor adopt the following policies:
1. German soldiers convicted as war criminals should be released.
2. Defamation of the German soldiers would have to cease.
3. Domestic and foreign public opinion of the German military would need to change.
This approach spread to the Western powers and President Eisenhower declared “a real difference between the German soldier and Hitler and his criminal gang.” It worked and the Bundeswehr was established.
This was a cover up. As the military arm of the Nazi state, the Wehrmacht was complicit in crimes against humanity, actively supported the Final Solution and committed war crimes on a vast scale. Ahead of the invasion of Russia the Wehrmacht was given carte blanche to abuse Russian soldiers and civilians without fear of prosecution and the military was instructed to carry out summary justice for Russian civilians. The infamous “Commissar order” issued by the army high command instructed soldiers to execute Russian political officers on sight. Prisoners of War were routinely executed or left to die through neglect. The war against Russia was declared to be a war of annihilation and so the Wehrmacht considered crimes against humanity to be a military method of achieving the political aim of exterminating Slavs and “Judeo-Bolshevism”.
Even before the invasion of Russia, the Wehrmacht had committed a number of atrocities against civilians in Poland and throughout the occupation of Eastern, Southern and Western Europe its domestic security role meant that it was entwined in the criminal affairs of the state. It helped to implement the “Night and Fog” decree, which allowed for the disappearance of suspected partisans leading to extrajudicial torture and execution; it implemented policies of discrimination and persecution against “undesirables”; and it took part in reprisals against civilians including summary executions, torture and rape. The Wehrmacht also maintained a network of military brothels in which local women were forced to work.
These were not isolated cases and nor were commanders or soldiers “just following orders”. For example General von Manstein issued an order to his soldiers in November 1941 including this:
> Jewry is the middleman between the enemy at our rear and the still fighting remnants of the Red Army and the Red leadership; more than in Europe, it occupies all key posts of the political leadership and administration, of trade and crafts and forms the nucleus for all disquiet and possible revolts. The Jewish-Bolshevist system must be exterminated once and for all.
Analysis of letters sent by German soldiers shows that this fervor spread throughout the ranks, with soldiers reporting that they were happy to execute partisans. They routinely took photographs of atrocities and consistently used Nazi language to describe their opponents and the civilian population as sub-human.
Intriguingly the Wehrmacht was not declared a criminal organisation at the Nuremburg trials because it was too disorganised to pass the legal test to be defined as an organisation.
If you’d like to read more then I highly recommend Wette’s *The Wehrmacht: History, Myth, Reality* and for an appraisal of the American view of the Wehrmacht, Smelser and Davies’ *The Myth of the Eastern Front*. | [
"The combined \"Wehrmacht\" military forces of Nazi Germany consisted of the \"Heer\" (army), the \"Kriegsmarine\" (navy), and the \"Luftwaffe\" (air force). While not technically part of the Wehrmacht, the \"Waffen-SS\" (\"Armed-SS\") tactically operated as such and was considered part of Germany's armed forces du... |
how large should a cult be to be considered a religion? | Those 2 terms aren't really mutually exclussive.
One man's terrorist is another man's freedom fighter.
Being a cult, isn't about size though. It's about how you behave:
+ Messianic leader.
+ Require members to cut off contact with "outsiders"
+ Strict enforcing of morals
+ etc...
I mean JW and scientology are huge, and they are still cults. And they will be forever. Unless you are one of them of course, then it's your religion. | [
"In the sociological classifications of religious movements, a cult is a social group with socially deviant or novel beliefs and practices, although this is often unclear. Other researchers present a less-organized picture of cults, saying that they arise spontaneously around novel beliefs and practices. Groups sai... |
why can we "develop a taste" for things we originally dislike, such as beer or certain foods? | My first reddit contribution, here goes nothin!
The human brain changes the way it perceives certain flavors as a survival mechanism. For instance, we develop a tolerance for the spiciness of peppers after the brain becomes aware of the good nutrients they contain.
Another example is a dude lost on a raft at sea for months but has a steady supply of fish he can easily catch. He just eats the meat at first, but after a time he gets cravings for the parts he originally found repulsive-organs and eyes- which contained vitamins he had become deficient in. His brain's innate ability to adjust his flavor perception kept him in good health by making him want to eat nasty stuff.
Source: _URL_0_
Edit: thanks to Roscoj for the vid link. Putting it here at the top. Skip to 8:10ish for the part relevant to this topic. | [
"An acquired taste is an appreciation for something unlikely to be enjoyed by a person who has not had substantial exposure to it. In the case of food and drink, this may be due to a strong odor (such as certain types of cheese, durian, hákarl, black salt, nattō, asafoetida, surströmming, or stinky tofu), taste (al... |
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