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if 4-word passwords are the safest*, then why does password managers like lastpass not do that? | 4-word passwords aren't stronger than a bunch of random characters. The xkcd you linked is comparing 4-words passwords to a specific *type* of password where you take a single dictionary word ("troubadour", in this case), swap some of the letters for similar-looking characters, and add a couple of random characters to the end. *That's not random*. It's an obfuscated dictionary word, and not a bunch of random characters.
The 4-word password mentioned in the comic has 44 bits of entropy. That's equivalent to a truly-random 8-character password that uses upper and lower case letters, numbers, and special characters.
The point that the xkcd comic was making was that people can't easily memorize random passwords, and the "tricks" that people use to make non-random passwords look random don't work. But people can memorize a sequence of words fairly easily, and that's more secure that taking a dictionary word and swapping out some letters in it.
But if you're using a password manager, memorization is no longer a limiting factor, so you should use long passwords with random characters. | [
"But passwords are typically not safe to use as keys for standalone security systems (e.g., encryption systems) that expose data to enable offline password guessing by an attacker. Passphrases are theoretically stronger, and so should make a better choice in these cases. First, they usually are (and always should b... |
Why are smaller animals more resistant to ionising radiation? | As far as I'm aware, we still don't *quite* know.
Compared to humans, we've known for some time that insects are generally more resistant to ionizing radiation, and multiple hypotheses have been proposed to explain this radioresistance.
For a long time it was thought that because actively dividing cells are those most sensitive to radiation, insects would succumb less as, unlike humans with our leagues of constantly dividing cells, insects undergo discontinuous periods of growth (only with every moult). But this whole organism approach to radioresistance was tricky to interpret, as the physiology between us and, say, invertebrates is very different.
At a cellular level however, experiments on cells controlling for proliferative rate have revealed that insect cells are *de facto* more radioresistant than human cells, leading us to believe division rate actually might only have a little to do with it. When you blast human and insect cells with ionising radiation, the DNA within the insect cells itself undergoes much less damage, and what damage is present is more effectively repaired. Likewise, those same insect cells experience lower oxidative stress as a consequence of radiation exposure (radiation triggers the production of rather harmful reactive oxygen species that, amongst other things, trigger cells to commit [apoptotic](_URL_0_) suicide).
So yup, it appears the suite of repair enzymes insects utilise are simply better at dealing with DNA damage, explaining why insects have greater radioresistance. As for the evolutionary reason why they're more efficient, we're still not quite sure.
___
^**Sources:**
[^(Cheng, I.C, Lee, H.J. & Wang, T.C. (2009)^) ^(Multiple factors conferring high radioresistance in insect Sf9 cells. *Mutagenesis* 24 (3)^), ^259-369](_URL_3_)
[^(Bianchi, N.O., Lopez-Larraza, D.M. & Dellarco, V.L. (1991)^) ^(DNA damage and repair induced by bleomycin in mammalian and insect cells. *Environ Mol Mutagen*. 17, 63-68)](_URL_1_) ^((research gate) [^here](_URL_2_)^) | [
"The comparison in the table below is only meant to give approximate indications of radioresistance for different species and should be taken with great caution. There are generally big differences in radioresistance for one species among experiments, due to the way radiation affects living tissues and to different... |
How did India become one country? how did it avoid civil war after independence? | This is a question which can only be fully answered over the pages of several books since the formation of the India Union spans nearly two centuries and the the geopolitics of the subcontinent is equally broad and complex. What ill attempt to do here is provide a summary that goes through various political, social and strategic processes that led to the contemporary situation in the subcontinent. Since I specialise in the history of the Indian Union the summary I give is primarily a history of the same entity. I wont be commenting much on Pakistan, Bangladesh and Srilanka for the same reasons.
At the end of colonial rule, British India was a vast territory that stretched from Afghanistan to Burma. Burma had been made a separate crown colony in 1916. The modern political geography of the current nation states of the Indian subcontinent derive from the British India of the early 20th century. Now British India was culmination of a variety of forms of political control. There were the Presidencies in Bombay, Calcutta, Delhi and Madras and the territories under these presidencies. This was under the direct control of the monarch of England from 1858. Interspersed between this territory were the Princely States which were ruled by local monarchs but were controlled by British Resident or Political Officer. At the time of Indian Independence these Princely States numbered around 556. It is within this political system that Indian nationalism began to emerge and grow. The main political entity in the Indian national movement was the Indian National Congress founded in 1885 but it is not the only anti-colonial entity that was active in creating the Indian identity. There were a variety of regional interests that created their own discourse of nationalism, nativity and anti-colonialism . The transportation, communication and political systems of British colonialism had made it easier for the subjects of British India to interact and share ideas to form a coherent identity. The modern Indian identity is not formed overnight but it took nearly a 100 years worth of poetry, literature and political activism to create the consolidated idea. It is also not a monolithic identity there are several sub-nationalisms that contribute to the larger idea. Its better to understand the Indian identity as aggregation rather than a singularity.
Recommended Reading : [Sumit Sarkar- Modern India](_URL_0_) [Shekar Bandopahyay- From Plassey to Partition](_URL_5_)
In 1947 India gained Independence from colonial rule. As political negotiations to keep India integrated with the same political geography as British India fell apart and the country split into two. Pakistan(which in 1947 was west-Pakistan and east-Pakistan which is present day Bangladesh). Minus this territory most of British India began to form the Indian Union. Now the present day political map of the Indian Union is not what the country looked like in 1947. In fact constant shifts occurred in the territory of India till 1976 (2016 if you count enclaves). In fact contrary to mainstream Indian historiography the Indian Union is the product of a series of negotiations conflicts and insurgencies. Initially several princely states objected to joining the Union. The state of travancore wanted to remain independent but a popular left wing uprising overthrew the monarchy and voted to join the Union. The state of Hyderabad was annexed by the Indian army in 1948, essentially because the state would have been a country within a country with strong ties to Pakistan. The princely state of Junnagad became a site of conflict as to if it would join Pakistan (because of the interests of it muslim monarch) or join India in the interest of its hindu majority(the latter was what happened). The reverse was true of Kashmir which had a Hindu monarch who after a speedy referendum ceded to India. Stating the muslim majority argument Pakistan invaded what is today azad kashmir/Pakistan occupied kashmir. This issue as you may know is still unsettled. There were other political negotiations that the Indian Union had to undergo to tip the balance in the French controlled territories of pondicherry, yanam and mahe. These territories would referendum out of colonial rule and accede into the Union. The Portuguese colony of Goa would also be absorbed into the union in 1961 through strategic military move by the Indian army. The latest change to the map of the Indian union happened in 1976 when the princely state of sikkim was made an Indian state. Sikkim had been an Independent kingdom during British rule. The Indian union had turned sikkim into a protectorate after the Indo-china war of 1962 taking over military and diplomatic affairs of the kingdom. In 1975 a controversial referendum and social strife against the monarchy in sikkim saw it absorption into the Union.
Recommended reading-
[vp menon- The Story of the Integration of the Indian States](_URL_4_) [Smash and Grab- Sunanda Ray](_URL_3_) [Andrew Duff-Requiem for a Himalayan Kingdom](_URL_2_)
As you can see from these examples there is a complexity of factors that created the present day Republic of the Indian Union.
> How did India avoid escalation of conflicts into civil wars?
There is no real answer for this. In fact the Indian union has always contained problems that in other nations would have definitely escalated into civil wars (or in India multiple civil wars). But the fact remains that the republic has always been strong and none of India’s internal conflicts have ever caused a breakdown of the entire system. This could be primarily because of how the Indian Union is designed. Unlike a standard nation state India is not a monolithic governmental entity. One allegory(not comprehensive) is to say India is like the European Union but with a state structure similar to the United States. Like the EU India is made up of several nationalities but like the US its it has a centralised government below which function very strong state governments. These state governments are small nations in themselves but military and economic policy is with the central government. This form of power sharing is significant reason for the sustenance of the Indian Union. Though demographic differences do favour certain cultures and linguistic groups in the union the states still hold significant autonomy. In fact except for a few cases the solution in the Union for conflict is often to co-opt opposing parties and give more self governance. By doing this the Union never escalates a conflict beyond a certain point.
At the same time this system is not without its fractures. A significant number of secessionist conflicts dot the history of contemporary India. Everyone knows about kashmir so I wont delve further into that. Apart from this India has had secessionist movements for several regions. The conflicts in north-eastern india are significant in this regard. Having been mostly outside direct colonial control and not fully linked to the politics of Indian nationalism most states in north-eastern India remained socially, culturally and linguistically different from the mainland. The political entity that was once British Assam further turned into 6 different states in the Union. All of these states have their own secessionist movements. Naga nationalism which still survives today in a few small insurgent groups hoped to create a separate nation ‘Kuknalim’, joining different naga tribes in Myanmar and the Indian states of Nagaland, Manipur, and Arunachal Pradesh. The Garo Liberation army pushed for separate state in Meghalaya and the Mizo National Liberation Front was formed to create a separate Mizo nation. Besides this there are several secessionist movements or movements that seek to form new Indian states like the United Liberation Force of Ahom, Boro Liberation Tiger Force. In the mainland there is a long history of maoist/marxist militias that span central, eastern and southern India. These groups consider the Indian state a semi-colonial, semi-feudal, capitalist entity and have been in conflict with the central government for decades.
All this has led to the Central government developing a series of military divisions that are deployed for a variety of conflicts. Unlike most countries Indian armed forces are of two type. The Indian military (Army/Navy/Airforce) which is controlled by the Defence Ministry and the Reserve Police controlled by the Home ministry. The Reserve Police play a significant role in the regulation of domestic conflict. They are essentially the counter balance. Within the reserve police there are divisions for border patrol, the Border Security Force for the Bangladesh/Pakistan borders, Indo-Tibetan Border Police, Sahastra Seema Bal(nepal-bhutan border), Assam rifles(Myanmar border), and the Coast Guard for the seas. For engaging in domestic often secessionist conflict the central government deploys the Central Reserve Police Force and the Rapid Action Force is a division sent for riot and crowd control. There are also division like the Central Industrial Security Force and the Railway Protection Force which is for infrastructure security. Apart from the co-optation and political/diplomatic negotiation the reserve police are the other side of how India ensures internal integrity. Most internal conflicts in India are fought by reserve police not the army.
Recommend Reading – [Steven Wilkinson- Army and Nation](_URL_1_) | [
"In 1947, India gained independence from the British Empire. The empire was in decline but adapted to these circumstances by creating the British Commonwealth—since 1949 the Commonwealth of Nations—which is a free association of equal states. As India obtained its independence, multiple ethnic conflicts emerged in ... |
How extensive was the system of slavery in Dutch South Africa? | /u/Khosikulu is the best person to address this question. However, I think he is supposed to writing a proposal right now. I'll give a college-try, though if he reads this he might dispute some aspects, or at least recommend some further literature on the matter.
> Did the Dutch enslave the local population, or were they importing slaves from elsewhere, or both? How extensive was the slave population?
In the period of Dutch rule up until 1790s, the majority of the slave population was imported from Mozambique, Madagascar, the Comoros, or else from Indonesia.^1
However, in 1807 the new British administration imposed a ban on overseas imports of slaves to the Cape Colony (as part of an over-all ban on slave trading in all the colonies of the empire). In 1807, the population of the Cape Colony stood at roughly 25,000 white settlers, 1,100 free blacks, and 30,000 slaves.
> Was this a plantation style system, plot-farming, or something else?
Slave labor was involved in all aspects of Cape colony society. Slave labor was used in warehouses and as longshoremen in Capetown, as fishermen, and as farm labor growing wheat and making wine in vineyards.
> How quickly did things change with the takeover by the British?
So, as I said above, the British imposed a ban on overseas slave imports in 1807. Britain had governed the Cape Colony from 1795-1803 before briefly returning control to the Dutch under the Batavian Republic. When Napoleon invaded the Batavian Republic in 1806, the British again took control of the Cape Colony that same year, and imposed their ban on slave trading the next year.
However, that ban on overseas trade could not completely cut off the flow of new slaves into the colony. Raiding across the frontier and capturing captives, or trading with African traders were also a source for slaves. Of course, the inflows of slaves from these sources were much reduced compared to the overseas trade. While there were roughly 30,000 slaves in 1807, slave numbers increased slightly to 32,046 in 1817, and to 32,243 in 1828. Importantly, this period also saw a shift in the geography of slavery. Some slave owners in Capetown were quick to take advantage of spikes in slave prices immediately after 1807, and sold their slaves to rural farmers. Also, since the eastern frontier was the only viable source for new slaves, the five eastern districts are the regions that see the increase of slave populations, reaching ~20% of total slave population in the colony by 1828.^2
The ban on slave imports also forced the Cape Colony to investigate other labor pools. In 1809, the colony introduced the pass system for contract labor, where free Khoikhoi adults in the colony were required to have passes that specified where the person worked and how long the term of service was. This pass system was introduced as a security measure after Khoikhoi uprisings during the Third Xhosa war.
In 1812, the a system of "apprenticeships" was also introduced, where Khoikhoi and San children were incorporated in the rural workforce. These apprentices were technically free, but they were not paid until they reached maturity at age 25. At maturity, they could theoretically seek alternate employment, but in practice there existed substantial barriers to employment mobility.
Prior to the introduction of the apprenticeship system, Khoikhoi had largely avoided systems of unfree labor, and played an important role in providing livestock in trade to the colony.
In 1834, the British decreed that slavery itself was now illegal in British colonies, including the Cape Colony. Slaves were to undergo 4 years of apprenticeship to prepare them for freedom, and were to fully enter the labor economy by 1838.
To quote Paul Lovejoy
> The beginnings of the Great Trek coincided with the emancipation of slaves in the British Empire, and the two were hardly unrelated
> ....
> In the long run, the emancipation of slaves and the further consolidation of the apprentice system [in the Cape Colony] were important steps in the evolution of a migrant labor force, **based on the issuance of passes to control settlement and employment.** the short term, many Boers took their slaves and Khoikhoi apprentices and moved inland to seize land for livestock and agriculture, for the devastation of the *dificane* wars had left the best land for settlement. Beyond the British colony, the apprenticeship system functioned as a thinly disguised form of slavery. The Boers who had left by 1837 took with them perhaps 4,000 apprentices and supposedly former slaves who continued to be treated as servile. the Trekkers also continued to seize children or buy them from the rest of the century; the Nguni at Delagoa Bay became one source of "apprentices" were slaves in the eyes of the Nguni. As late as the 1890s, this modified form of slavery continued in the Transvaal, the Orange Free State, and Natal, although by then free migrant labor was more important as a source of manpower than slavery.^3
Emphasis mine.
I think that quote also helps answer your last question. The control of migrant labor and settlement that the pass laws addressed in 1834 would continue to be an animating issue for South African society throughout the 19th and 20th centuries, and labor passes would continue to be used by the Apartheid state.
On the other hand, if we accept Lovejoy's proposition that the Great Trek was connected to the emancipation decree (in addition to Boer perceptions of Anglo discrimination), then 20th century conflicts over land rights and access can be said to be indirectly related to the end(?) of slavery in 1834.
---
1 _URL_0_
2 *Transformations in Slavery* by Paul Lovejoy, chapter 10 "Slavery in Central, Southern and Eastern Africa in the Nineteenth Century" pp 232.
3 ibid, p232-233 | [
"Although slavery was illegal inside the Netherlands it flourished throughout the Dutch Empire in the Americas, Africa, Ceylon and Indonesia. The Dutch Slave Coast (Dutch: \"Slavenkust\") referred to the trading posts of the Dutch West India Company on the Slave Coast, which lie in contemporary Ghana, Benin, Togo a... |
If the brain can't feel pain, why are aneurysms (sometimes) so painful? | The brain may not feel pain, but the dura mater, a sac that surrounds the brain, does. Any pressure on the dura can affect the trigeminal nerves and upper cervical nerves, causing extreme pain. I have intracranial hypertension, where I produce too much cerebrospinal fluid, so I was given a shunt to drain it. The shunt worked too well and created over drainage, which caused my brain to sink into my brain stem (called Chiari Malformation ). I was in severe pain due to the brains connections to the dura being pulled on, triggering the nerves and basically dropping me to my knees in pain multiple times a day. While not an aneurysm, the symptoms can be similar. I've had pressure headaches from having too much fluid, and headaches from not having enough. Hope that helps. | [
"The brain itself is not sensitive to pain, because it lacks pain receptors. However, several areas of the head and neck do have pain receptors and can thus sense pain. These include the extracranial arteries, middle meningeal artery, large veins, venous sinuses, cranial and spinal nerves, head and neck muscles, th... |
how can i see a movie trailer (suicide squad) that basically looks like the movie is "done" but the release date is more than a year? | Hi, design student here - film is not my main subject but I've done a few storyboards for film productions at my university and could get a bit of insight on the production process.
First of all, what you see in the cinema is only a very small fraction of what has been filmed (recently I read something about Mad Max: Fury Road footage adding up to nearly 500 hours in total). In the cutting room, scenes will be picked and recombined - and the scenes selected for the trailer will go into post-production (color grading, cgi, foley etc.) while the rest of the movie won't be finished necessarily.
The outline of the story and the look & timing of every scene are designed in the screenplay and the storyboard & animatic long before the movie is actually shot, so here important scenes can already be highlighted.
And, of course, there are also marketing reasons - for example, the launch date of the Warcraft movie has been postponed to 2016 because of Star Wars coming out this fall (this was one of the reasons, at least).
Just have a look at Peter Jackson's making-ofs from Lotr/ the Hobbit... this guy and his team were in the studio working on the SFX only minutes before they had to send out the final product.
So, I hope that was helpful and you can understand what I'm trying to say - English is not my first and I'm writing on mobile, being too lazy to proofread :)
Edit: I forgot to add - YES, there is so much to do in post (and pre-) production! Here we have one semester to finish a project (=short film, from 30 seconds up to maybe 10-15 mins). Actual shooting takes a few days, normally, sometimes up to one week - and the rest of the time is taken up by pp. | [
"The movie itself is presented as being a trailer for a 9 hour long movie. It starts with a voice-over, telling the viewer that: \"\"some murders take seconds; some murders take minutes; some murders take hours; this murder... will take years!\"\".\n",
"On December 17, 2018, IGN released an exclusive teaser poste... |
Why do we grip smooth things better than rough things? And grip better when our hands are slightly wet rather than dry or soaked? | I wrote an answer about this earlier [here](_URL_0_). Briefly, the answer is that the friction between your hand and the glass depends most strongly on adhesion (a non-specific attraction between the molecules in your hand and the surface of the glass). Smoother glass results in a larger effective contact area, and hence more friction.
Edit: Oh and in the case of wet vs dry hands, the friction decreases drastically if the hands are wet. The reason is broadly called "water lubrication," which doesn't in itself say much, but it has been attributed to a film of water separating the skin from the glass. | [
"Surface roughness can also affect the adhesive strength. Surfaces with roughness on the scale of 1-2 micrometres can yield better wetting because they have a larger surface area. Thus, more intermolecular interactions at closer distances can arise, yielding stronger attractions and larger adhesive strength. Once t... |
why does driving on an overpass create a higher pitch sound than driving on a surface street? | Sometimes bridges are "paved" with a different material than the rest of the road. It could be concrete/cement instead of tar, it could be a different type or blend of tar.
But you might also be hearing the pavement vibrate more because it is open underneath and the sound has a chance to cause sound waves in the air. When you're on flat road, the sound just soaks into the ground and doesn't get much chance to create sound waves. | [
"Cars significantly contribute to noise pollution. While on common perception the engine is the main cause for noise, at city speeds the noise produced by wheel and asphalt is commonly the dominant factor while at highway speeds air friction noises become a major factor.\n",
"Roadway geometrics and surrounding te... |
why can't doctors replace a failing heart with a mechanical pump system? | Take a look at HeartMate, the market leader in heart pumps. They are typically given to people on the waiting lists for donor hearts though are increasingly used as a 'destination therapy', that is, in patients who do not go on to get a whole new heart.
There are lots of fun distinctions in the devices. There are pulsar (beating like a normal heart) or continuous flow devices; surprisingly, the pulsing action of a natural heart isn't strictly necessary. In fact, there are some advantages in having a continuous flow, particularly in managing blood pressure (fewer large 'spikes'). Typically they are used in conjunction with a weak heartbeat that could use some help... Some people envisage a wholly 'dead' heart just sitting there doing nothing, but that doesn't really happen. It just beats weakly and irregularly.
The real issue with these devices is that you need a drive line from the pump, inside your chest cavity, out through your belly and into battery packs on the outside. You need pretty heavy duty battery packs to keep a heart pump going, so they have to be external. Having a fairly sizable wire coming out of your body creates issues with infection. It's also important to note that most people getting heart pumps are pretty sick already - they often have other medical issues... So mortality in the following years is very high.
All of that said, people with heart pumps have completed marathons. So if your general health is good and you just have a dodgy ticker, it can really improve and extend your life.
| [
"The Artificial Cardiac Pump temporarily takes over the function of breathing and pumping blood for a patient. It has two parts, the pump and the aerator. Cardiac pumps are most often used in heart surgery, so that a patient's heart can be disconnected from the body for longer than the twenty minutes or so it takes... |
in america, why is taking the bus looked down upon, more so than taking the train/subway/taxi? | It's a social status thing.
It isn't necessarily true everywhere, but buses tend to have routes mostly or entirely in the city, not in the areas that upper class people care about. Trains and subways will have stations that travel out of the city to the suburbs, so more wealthy people can travel into the city for work, and back out where they live. Taxis generally aren't cheap so if you can afford them, you're pretty well off. Busses are the cheapest form of public transportation, so they tend to be used most by people in the lower class. | [
"However, this system also creates a noticeable problem with people bunching up near the front of the bus during times when customers pay on exit. People are reluctant to move to the rear of the bus for fear they will have difficulty getting out, as only the front door is used as both entry and exit during these ti... |
Besides the Anabasis, is there actually any other information to corroborate Xenophon's Persian Expedition? | Artaxerxes II had a Greek doctor, Ctesias, who wrote a Persian history that mentions Cyrus the Younger's campaign. It is extremely fragmentary. [Here](_URL_0_) is a translation of the relevant fragmentary. It's preserved in Photius, a Byzantine Patriarch. The fragment notes Cyrus brought Greeks and names Clearchus as the Greek general, and claims Ataxerxes reached an arrangement with the Greeks. No mention of Xenophon in the fragment.
> (63) Cyrus revolted from his brother and assembled an army mixed of Greeks and barbarians
with Clearchus as the general of the Greeks. Ctesias describes how Syennesis entered into an
alliance with both Cyrus and Artaxerxes and how each man advised his own army.
Clearchus, the Spartan who led the Greeks, and Menon the Thessalian, both allies of Cyrus,
were always at odds with each other because Cyrus always deliberated with Clearchus while
he did not rely on Menon at all. Many men deserted from Artaxerxes to Cyrus but no one
deserted from Cyrus to Artaxerxes; consequently, Arbarios intended to join Cyrus but was
betrayed and thrown into the ashes. (64) Cyrus attacked the king's army, won a victory, but
died in the battle when he failed to follow the advice of Clearchus. His body was mutilated
by his brother Artaxerxes, who cut off his head and the hand which he used to wound the
king and paraded around with them. (65) Clearchus the Spartan retreated with his Greek
contingent during the night and occupied one of the cities under Parysatis' dominion.
Finally, the king concluded a peace with the Greeks. | [
"BULLET::::- \"Anabasis\" (also: \"The Persian Expedition\" or \"The March Up Country\" or The \"Expedition of Cyrus\"): Provides an early life biography of Xenophon. \"Anabasis\" was used as a field guide by Alexander the Great during the early phases of his expedition into the Achaemenid Empire.\n",
"Written ye... |
explain this eyeglasses prescription li5 | Each set of 3 numbers are instructions for the lens crafter, telling them how to combine two geometric shapes (a spherical lens and a cylindrical lens) into the final piece of glass or plastic.
It's sort of like if someone gave you a drawing of a square and a drawing of a circle. The two drawings have very precise measurements. It's your job to use some play-doh and make a new shape... a square with rounded corners, using those exact measurements from the drawings.
The rest of this is a bit more technical... five-year-olds, put on your reading glasses!
For the first eye (assuming right), start with a spherical lens with a diopter of -2.00. Next, to adjust for astigmatism, add a cylindrical lens with a diopter of -0.25, rotated 165 degrees counter-clockwise from the horizontal.
Same deal for the second eye (assuming left): spherical -1.75 + cylindrical -0.25 rotated 5 degrees counter-clockwise.
A [diopter](_URL_2_) is a measurement of how curved a lens should be. Negative means concave, positive means convex. The further away from 0.0, the stronger the effect. In your case, this means your right eye needs slightly more correction than your left. The negative diopter means you're near-sighted.
[Astigmatism](_URL_0_ is a common condition where things blur in one direction. The rotated cylindrical lens corrects this. Each eye can have its own astigmatism.
Those 6 numbers are the basics, though there are several other important measurements and other nuances, such as the distance in between your pupils. The Wikipedia article for [eyeglass prescription](_URL_1_) is a good reference if you want more gory details. It has some good illustrations of what a cylindrical lens and various diopters look like (kind of hard to describe in words). | [
"An eyeglass prescription is an order written by an eyewear prescriber, such as an optometrist or ophthalmologist, that specifies the value of all parameters the prescriber has deemed necessary to construct and/or dispense corrective lenses appropriate for a patient. If an examination indicates that corrective lens... |
How is CRISPR/Cas9 delivered to the body? | We don't use CRISPR in human bodies, so the answer to your question is "it isn't".
But in mice, people have done AAV and lentiviral delivery of CRISPR/Cas9. Naked DNA rarely does any good, and DNA in a pill would just get digested. People are working on other delivery vehicles, like liposomes, polymersomes, etc. | [
"CRISPR is a repeated, short sequence of RNA that match with the genetic sequence that the scientists are aiming to modify or engineer. CRISPR works in rhythm with Cas9, an enzyme that splices the DNA. First, the CRISPR/Cas9 complex searches through the cell's DNA until it finds and binds to a sequence that matches... |
why is a ladder more stabile for the person climbing when there is another person standing on the other end? | Because to climb the ladder, you need to lift a foot off it to go up a rung. That places all your weight on the other foot temporarily, meaning that all the weight is now on one side of the ladder, which can cause it to lean.
If you have someone standing on the other side, it adds weight, keeping the ladder from shifting when you lift a foot. | [
"A ladder standoff, or stay, is a device fitted to the top of a ladder to hold it away from the wall. This enables the ladder to clear overhanging obstacles, such as the eaves of a roof, and increases the safe working height for a given length of ladder because of the increased separation distance of the two contac... |
What do we actually sense when we feel that something is wet? | The typical sensation of wetness is related to the coolness of the evaporative effect. When we are wet, either from sweat or an external source, the water is immediately drawing heat from our skin as it evaporates. Hot or warm water splashed on us feels different at first because it's actually adding heat. It feels wet and uncomfortable as soon as its temperature drops below our body temperature.
Mercury does not evaporate. It and other non evaporating liquids may give a sensation of its presence, but won't feel cold like water or alcohol. | [
"The wetness of skin in different areas also affects perceived thermal comfort. Humidity can increase wetness on different areas of the body, leading to a perception of discomfort. This is usually localized in different parts of the body, and local thermal comfort limits for skin wettedness differ by locations of t... |
the process of data encapsulation (networking) | What do you want to know, specifically?
In general, each layer of the OSI model operates independently of the rest. Data encapsulation is how each layer takes the bits from the previous layer and transports them without messing them up.
Analogy: You want to ship a care package across the ocean. YOU and the RECIPIENT only care about the contents of the care package, not how the details of shipping. You pack the contents in a box and send it to Fed Ex. Fed Ex only cares about moving the box, not what's inside it. They pack up a bunch of boxes into a crate and send it to the airstrip. The airplane crew only care about moving the crates safely, not what's inside them. They load a bunch of crates onto a plane. The plane crew only cares about moving the plane safely, not what's in the cargo bay.
The plane lands, so the ground crew unpacks the cargo bay and hands the crates to Fed Ex. Fed Ex unpacks the crates into boxes and hands them to the recipients. The recipients unpacks the boxes and enjoys the contents you originally put inside.
Every time the contents change hands, the new transport layer wraps it into a larger assembly for safe transfer, and they do not care what is inside. | [
"In computer networking, encapsulation is a method of designing modular communication protocols in which logically separate functions in the network are abstracted from their underlying structures by inclusion or information hiding within higher level objects.\n",
"A node stream is a method of transferring large ... |
[META] Medial Advice on AskScience: The Guidelines. | Thank you for typing this up and getting it out there. I try to make sure I reinform others, and report when necessary as this occurs.
I know that some of you guys aren't going to like that we can't allow this, but that doesn't matter. It doesn't matter that you're certain whatever is bothering you is trivial. You could be the 1 in 1,000,000 for whom it's deadly. It just isn't worth it, even with those odds.
Please, go to a doctor or a clinic if you are going to post about yourself here. You only get one body, so by all means, get your monies worth out of the damned thing, but take care of it, and yourselves too. We don't want to lose any of those who make this community great (and really, that's the people who ask questions) to something that could have been prevented. | [
"Brief Answers to the Big Questions is a popular-science book written by physicist Stephen Hawking, and published by Hodder & Stoughton (Hardcover) and Bantam Books (Paperback) on 16 October 2018. The book examines some of the universe greatest mysteries, and promotes the view that science is very important in help... |
Are there any models in which causality breaks down? | There are some models of naked singularities which allow for [time travel and causal loops](_URL_0_).
The problem is that we don't understand gravity well enough to know if naked singularities are even possible, and then we don't know if we're right about how physics would go wonky near them.
As for what this would mean for the Big Bang. I don't think I'm up to trying to explain the general relativity, but at the Big Bang it was a different type of singularity, and I haven't seen anything directly addressing how that singularity would affect causality (although my quick skim on one of the papers suggests that the causality problems only apply to black hole singularities).
Questions about whether or not "causality was created at the Big Bang", or if time even had any meaning before the Big Bang are beyond me. | [
"In TSVF, causality is time-symmetric; that is, the usual chain of causality is not simply reversed. Rather, TSVF combines causality both from the past (forward causation) and the future (backwards causation, or retrocausality).\n",
"In philosophy of science, a causal model (or structural causal model) is a conce... |
what's the point of voting for the president(us)? | The President:
* Is command-in-chief of the Armed Forces. Although he cannot declare war, he can order troops to mobilize and is ultimately in charge of the entire military.
* Sets policy for the federal government. What's not codified in law can be affected by his political leanings, e.g. directing the FBI or Department of Justice to do certain things.
* Can sign executive orders which have the full force of law as long as they are not in contradiction with existing laws (they have limits but are still quite powerful)
* Nominates judges and Supreme Courts justices
* Has the power of veto making it very difficult for oppositional parties to pass controversial legislation without a supermajority
Probably a few things I'm forgetting but those are some of the big ones. | [
"The President has a casting vote (in the event of an equality of votes). Like the Speaker, the President continues to attend party meetings, and at general elections stands as a party candidate. On the other hand, the President does not usually take part in debates in the Council and does not speak in public on pa... |
How much mathematics was used in Greek and Roman architecture? | It's difficult to give a general answer, because specific projects would require specific approaches, but I think it's safe to say "not very much".
If you read an ancient architectural treatise like [Vitruvius',](_URL_1_) you'll see lots of references to numbers, proportions, and famous mathematicians, but nothing in the way of formulae for mathematical techniques for deriving constraints on architectural feature, and certainly nothing at all on how to calculate stresses. [Section 3.1](_URL_3_) has a lot of numerological trivia about "perfect numbers", but it's more about superstition than engineering; the [introduction to book 9](_URL_2_) has reports of amazing feats performed by famous mathematicians, but no guidelines for general architectural practices. It seems like architects were encouraged to have an interest in maths, but it was *very* hit and miss.
For further reading, [here's an old discussion](_URL_0_) that touches on this subject pretty closely. and links to some further material. | [
"Greek mathematics was technically advanced and we know for certain that they employed and understood the principles of pulleys, which would have enabled them to build jibs and cranes to lift heavy stonework to the upper parts of buildings. Their surveying skills were exceptional, enabling them to set out the incre... |
How is the focal length of a gravitational lens determined? | [This page](_URL_0_) has some good info and a set of included references. We have to get out to about 550 AU to use the gravitational lens of our star. Apparently that's where the corona doesn't obscure what we can see via the gravitational lens. There is no focal point, there is a focal line that extends great distance out. As I understand it, as long as you are on that line you can use the gravitational lens.
[This StackExchange discussion](_URL_1_) also provides some good information.
[This Technology Review article](_URL_2_) covers some of the same ground as well, but gives some different details.
Hopefully that sets you out on the right track. | [
"The focal length of an optical system is a measure of how strongly the system converges or diverges light. For an optical system in air, it is the distance over which initially collimated rays are brought to a focus. A system with a shorter focal length has greater optical power than one with a long focal length; ... |
what causes the sun to make our skin brown? | Biologist here!
Its a protection method by our body.
As the UV radiation reaches the lower levels of our skin, it tickles melanocytes, cells that basically act like photoreceptors
They detect the radiation and release Melanin, a pigment that browns our skin, making it harder for UV radiation to penetrate into the soft squishy stuff our skin is meant to protect. | [
"Melanin in the skin protects the body by absorbing solar radiation. In general, the more melanin there is in the skin the more solar radiation can be absorbed. Excessive solar radiation causes direct and indirect DNA damage to the skin and the body naturally combats and seeks to repair the damage and protect the s... |
What would the rule of the Dalai Lama have been like? | I've answered this question in depth before. [My first answer](_URL_0_) on r/AskHistorians was actually a variation of this question and it's still the most popularly asked question regarding the history of Tibet.
> 'disgusting how the liberal left embraced the Dalai Lama when he was more or less a theocratic dictator in Tibet,' implying vaguely that perhaps the Chinese annexation of Tibet was a good deed.
This is a good alarm system you have going. Statements like this are usually accompanied with justifications for the Chinese activities from the '50s to today... glossing over the way the People's Republic (often violently, and always forcefully) dismantled the Tibetan society, often by packing the committees and government bodies that actually did any governing with Han Chinese and Party cadres, while placing Tibetans in figurehead positions (they did this with the Dalai Lama himself from roughly '56 on) as evidence that Tibet was a willing partner in their "liberation."
Statements like this imply that the Chinese "liberation" solved all of Tibet's problems and established a modern functioning society without slavery and imperialism (accomplished by Marxist-Maoist ideology which simply states that imperialism and slavery are simply "impossible" under Communism, therefore under a Communist regime, by definition there is no slavery or imperialism...). And then completely ignore the forced collectivization of the '50s and '60s, the involuntary seizure of cultural artifacts, the thousands of tonnes of gold stolen from Tibetan monasteries which was sent to Beijing, melted down into gold bars, (and then mysterious, the PRC paid off all of its debt to the Soviet Union in 1965. Weird timing, huh?).
Even today there is a lot of problems between Tibet and China and any consideration or balance is usually taken as a form of dissent which makes discussion on this topic very difficult. It's easy to see why: both Tibetans and Chinese have faced centuries of discrimination (religious and ethnic) at the hands of outsiders and are defensive about their history. Rightly so. Though Tibet was certainly not a "Shangri-La" that westerners (and Tibetans themselves) often portray it. Nor was Post-Liberation Tibet suddenly a happy place where poor Tibetans were lifted up by Communist brethren (as Chinese propaganda portrays it).
> Would a rule for Tibet under the Dalai Lamas have been 'good?'
This is a fundamentally impossible question to answer. Most Tibetans will answer "yes," and most Chinese will answer "no," for reasons stated above.
Tibet from 1912 - 1950 was in a period of state-building. The Thirteenth Dalai Lama (the current one's predecessor) was trying to build Tibet into a modern, independent state. And that necessarily involved developing the country, modernizing the military, cracking down on the tax code, and then suppressing dissent.
This process isn't unique to Tibet, and is in fact something we can trace through primary source documents in any society and country that has made it from a medieval period ruled by an upperclass religious-based elite, to modern statehood. Even Bhutan has gone through this process, and one of the explanations of the nastiness that happened in the early '60s and the early '90s is a part of the state-building process. India is arguably still going through this process.
State building is, again, arguably, good for many at the expense of the few because it often necessitates modern medicine, modern infrastructure, modern social institutions, and increased civil liberties compared to medieval societies where the concept doesn't exist (though this last point is increasingly being challenged).
> Would the Dalai Lamas' rule have been liberal, focused on education, given opportunities for capitalism and fair and free markets for wealth generation, free migration within the country and free speech (excluding lese majeste I suppose).
Again, this is impossible to answer and it's impossible to speculate about alternate history scenarios (not least of which because it is against the rules of this sub.
BUT, what we can answer definitively is that the young Fourteenth Dalai Lama was very pro-modernity and even pro-Marxist. The Dalai Lama has said quite often that he believes Buddhism is the answer to people's Spiritual Needs while Marxism can be the answer to their Material Needs. He and the Panchen Lama went and visited Mao in Beijing in 1954. When the Dalai Lama returned to Tibet (he would stay there until 1959) he was excited that Mao seemed willing to work with and respect the Tibetan's wishes for a slow transition to socialism as opposed to rapid developments.
The PRC had actually told the Tibetans several times during their "liberation," that they had come to liberate the Tibetans from feudalism and serfdom. And once they were liberated, they would not stay "even if you begged us to." Obviously, that's not how it worked out. And the increasingly heavy hand of Chinese rule eventually convinced the Dalai Lama and those closest to him to fear for his life, so he fled to India. Even in exile, Beijing still believed it was possible to work with the Dalai Lama, who has certainly changed in exile: becoming pro-democracy, pro-education, pro-science, etc. etc. How many of these opinions were formed in Tibet and how many in exile? Hard to say. He has dozens of books out, his autobiography *Freedom in Exile* and the many essays and publications on his website (take careful note of the dates) are good indications of the opinions he held and when.
It actually wasn't until the 1980s and '90s that Beijing formally turned against the Dalai Lama and stopped trying to court the exile administration in Dharamsala. They wanted to try and get His Holiness back to Tibet to legitimate their rule, but after a few short visits of his brothers to Tibet that ended in a publicity disaster (especially for PRC relations with Taiwan) Beijing decided to stop portraying the Dalai Lama as a loyal, but misguided Communist, and start publicly calling him a "splittist" despite the fact that the Dalai Lama has consistently, since 1950, advocated a "Middle Way" approach to union with China: where Tibet was able to manage its own affairs underneath a Chinese government that would manage Tibet's international affairs.
> Is there historical precedence for this?
I would say yes: Bhutan is a good example, and of extreme interest to me, because it's the only example we have of a Tibetic culture zone that has been able to function and develop with minimal outside interference.
One comment you often see, esp. here on Reddit, but in any article about the Dalai Lama or Tibet with comments open, is that the Lamas "want their slaves back." Though (as you can see from my original comment in the link above) "slavery" and "serfdom" aren't the same in English language, and they are very different institutions in Tibetan history as well.
Not only that, but Bhutan banned both practices in the early '50s, and then even allocated royal land to the newly freed Drap and Zap so they could move away from their former masters and not feel awkward about the situation.
It's impossible to note when an independent Tibet would have done something similar and made those institutions illegal, again because that's alternate history and it's impossible to know, but it's important to note that every other country in the world has criminalized slavery and approximately 0 of them have needed the People's Liberation Army to do so.
Sources:
*Tibet: A History* by Sam Van Schaik
*Tibet: A Political History* by W.D. Tsepon Shakapba
*Dragon in the Land of Snows* by Tsering Shakya
*Tibetan Nation* by W. Smith | [
"The Dalai Lama had a strong following as many people from Tibet looked at him as their leader from not just a political point of view but, also from a spiritual perspective. After the Dalai Lama's government fled to Dharamsala, India, during the 1959 Tibetan Rebellion, it established a rival government-in-exile. A... |
why do most products have a "made in (country)" label? | It's a requirement for (most) products imported into the USA.
[Source 1](_URL_0_.)
[Source 2](_URL_1_) | [
"Many companies highlight the fact a product is made in the U.S. with their branding and marketing campaigns, benefitting from the huge marketing potential, often affecting the success of a product. Country of origin is a typical heuristic used when purchasing, playing a significant role in consumer perception and ... |
How has light had time to reach us from distant stellar phenomena? | > More precisely what I mean is, if our universe is only 13-14 billion years old, how has light from objects that are 40 billion light years away reached us.
The objects were much, much closer when they emitted the light. Over time, the distance between us and the light and the distance between us and the object expanded. As a result, the light took 13 billion light-years to reach us, and the object got to be 40+ billion light-years away. | [
"By thinking of photons of light as ants crawling along the rubber rope of space between the galaxy and us, we can see that just as the ant can eventually reach the end of the rope, so light from distant galaxies, even some that appear to be receding at a speed greater than the speed of light, can eventually reach ... |
why are ancient names like those belonged to the pharaohs so different, where do they come from, and what do they mean? | Probably most Ancient Egyptian names would sound alien to us, as they are from a language that evolved over a nearly 2,000 year span which predates most modern languages and which is only now used in very, very limited Coptic religious circles.
In reality, the word "Tutankhamun" is nothing too foreign - it means "Living image of Amun". His birth name was actually Tutankhaten - the living image of Aten.
Lots of Egyptian names were spiritual like this, or sometimes even just adjectives (like "Neferet" means "beautiful woman"). | [
"Pharaoh (, ; \"Pǝrro\") is the common title of the monarchs of ancient Egypt from the First Dynasty (c. 3150 BCE) until the annexation of Egypt by the Roman Empire in 30 BCE, although the actual term \"Pharaoh\" was not used contemporaneously for a ruler until Merneptah, c. 1200 BCE. In the early dynasty, ancient ... |
how can animals like the celiocanth and alligator gar who are considered "living fossils" go millions of years without really evolving all that much. | They're evolving the entire time just like everything else. The difference is that their form is relatively well suited to their environment, and so they don't show a lot of deviation in form. If your form is already well suited, then changes from that are less likely to be more successful. That shouldn't be confused with evolution actually stopping though. | [
"Most fossil sharks from about 300 to 150 million years ago can be assigned to one of two groups. The Xenacanthida was almost exclusive to freshwater environments. By the time this group became extinct about 220 million years ago, they had spread worldwide. The other group, the hybodonts, appeared about 320 million... |
When military commanders in middle ages were making strategies and decisions, would they really consider chivalry as a important thing? | Medieval conceptions of "chivalry" were multifaceted, confusing, and often contested. There were multiple meanings of the term and different ways of understanding it. It is better to think of the concept in terms of "chivalric culture" as opposed to a singular, codified "chivalry." Popular modern understanding of chivalric culture is pretty warped, often driven by 19th century misconceptions, romantic mythology, and stereotypes. However, in the medieval period itself, commanders did not see chivalry and clever military scheme and plots to be in opposition. They launched raids against unprotected enemy holdings, ambushed poorly prepared enemy forces, strove to outflank and outmanuever their opponents, carried out attacks at night, bribed captains to surrender their fortresses, and numerous other "dirty tricks." Many people imagine that there was some kind of knightly antipathy towards the use of missile weaponry, artillery, or combat on foot. Even a cursory examination of the most famous medieval battles reveals that this was not the case. Far from the stereotypes about foppish, arrogant, and ineffectual aristocrats, medieval commanders were often hardened, experienced soldiers with a hard-won understanding of the practical realities of the battlefield. They were quite capable of bending or breaking customs as they saw fit. A famous example of this behavior is the debate surrounding the killing of prisoners at several famous battles. In general, a soldier who had surrendered could expect mercy from his captors, but sometimes a commander might decide that killing their prisoners was necessary. While there is often a clear discomfort with and distate for these actions, they should not be considered "war crimes" in the modern sense. French chronicles might express sorrow when English soldiers killed French captives, but they did not attack such actions as "dishonorable." | [
"Chivalry developed as an early standard of professional ethics for knights, who were relatively affluent horse owners and were expected to provide military services in exchange for landed property. Early notions of chivalry entailed loyalty to one's liege lord and bravery in battle, similar to the values of the He... |
michelin star restaurant ratings | > Why is a tire company the sponsor of such a prestigious rating system?
It started in the era when tire companies wrote a lot of travel guides. The Michelin Star system indicates restaurants that they are very good.
> Is 3 stars the best rating that can be provided?
Yes. Those with 3 stars are specifically noted as being good enough that can be the reason for your trip.
> Who votes?
The method the Inspectors use for determining value is not publicly known.
> Once you get your stars, can they ever be taken away?
Yes. The inspectors re-evaluate periodically, but how often they re-evaluate is not publicly known. When you are re-evaluated you can lose your star, or gain more.
> Where can one get the entire list of rated restaurants?
They are generally listed by country and you can find them easily with a google search. You may need to list the year to get specifics.
| [
"Michelin stars are a rating system used by the blue Michelin Guide to grade restaurants on their quality. The guide was originally developed in 1900 to show French drivers where local amenities such as restaurants and mechanics were. The rating system was first introduced in 1926 as a single star, with the second ... |
If every gasoline car/truck on earth suddenly switched to a Hydrogen Fuel Cell, emitting only water vapor as exhaust, would there be a negative environmental impact? | A lot depends on how the hydrogen gas is produced. Electrolysis of water, for example, takes a very large amount of energy, and if you want a high purity output, you require a high purity input...thus, you're likely looking at distilling water before electrolysis.
How the energy that powers the electrolysis has to be taken into consideration. If we're using fossil fuels to power an electrolysis plant, then we're still dumping hydrocarbon pollutants into the atmosphere. If we're using nuclear power for electrolysis, we still have to deal with the waste products.
| [
"As of 2009, motor vehicles used most of the petroleum consumed in the U.S. and produced over 60% of the carbon monoxide emissions and about 20% of greenhouse gas emissions in the United States, however production of hydrogen for hydro cracking used in gasoline production chief amongst its industrial uses was respo... |
To what extent did organised natural disaster relief exist in Europe during the late Middle Ages and Early Modern period? | Since noone answered, perhaps a piece of info from the roman times could prove interesting, even if largely unrelated to your question. A flood destroyed a dam in central Greece. It was the dam that kept lake Copais dry (the previously submerged land was now farms but the flood destroyed the crops and some infrastructure). Locals, who at the time were conquered by Romans (I think the incident took place in 1st century AD) sent an "embassy" to Rome, then Rome decided to give them some funds for rebuilding the dam plus 5 years tax-free status. Sorry for not having the Greek source available now. My point is that if this happened so early, then it is very likely that similar relief actions would have taken place in the period you are interested in.
This lake was dried many times since at least 1200 BC but natural disasters or acts of war (usually by the neighbours) often flooded it again. | [
"The crisis of the Late Middle Ages was a series of events in the fourteenth and fifteenth centuries that brought centuries of European prosperity and growth to a halt. Three major crises led to radical changes in all areas of society: demographic collapse, political instabilities and religious upheavals.\n",
"Th... |
how have we as humans not become immune to the cold virus? | 'The cold virus' is not just one thing, but consists of multiple strains. When you become immune to one, you're not automatically immune to the others. On top of that, viruses mutate, so there's always a freshly mutated version out there that you aren't immune to. | [
"Along with HCoV-229E, a species in the Alphacoronavirus genus, HCoV-OC43 are among the known viruses that cause the common cold. Both viruses can cause severe lower respiratory tract infections, including pneumonia in infants, the elderly, and immunocompromised individuals such as those undergoing chemotherapy and... |
How does human cells replicate to form specific organs, features and continue developing without breaking the pattern? | It's a very complicated process and not every detail is understood but it boils down to signals which change gene expression. Every nucleus contains an organism's entire genome. Depending on which genes are used, a cell can take on different shapes, functions, and locations in the body.
Regulation happens at many levels, only certain parts of DNA may be expressed, or only certain proteins may be retained while others are broken down. Signals (such as cell signalling) can control the process, proteins such as those regulating cell adhesion are important too and can lead to certain cells congregating to form tissues.
Developmental biology is a whole field of study so it is tough to concentrate it in a single post. | [
"Cells in the body function because of DNA. DNA sits within the nucleus of a cell. Here, parts of DNA are copied and sent to the body of the cell via RNA. The RNA is then used to create proteins which form the basis for cells, their activity, and their products. Proteins dictate cell function and gene expression, a... |
Defeated crusaders were often presented with a choice: convert to Islam or die. What happened to the ones that converted to Islam? Did they assimilate into their societies? | > Defeated crusaders were often presented with a choice: convert to Islam or die?
Do you have a source for this assertion? I can’t claim that the crusades are a specialty of mine, but I’m not familiar with this claim.
| [
"For eight days, the Crusaders resisted thirst and a rain of arrows and smoke from the Turks. After, the leader of the Germans offered to surrender and to fight for the Turks. The fort surrendered on September 29, 1096. Some of the Crusaders who converted to Islam became slaves, while others who refused to abandon ... |
why do humans have more problems with teeth compared to other animals? | You are assuming that other animals have fewer problems than us. I have no data about wild animals. However, as some others have said we tend to eat foods which we did not evolve the ability to handle, like large amounts of sugar. Moreover, some of our dental problems arise from the rapid evolution of the human head and jaw. Our jaws have become smaller but we have retained the same number of adult teeth. So, in many people, there are issues with the Wisdom teeth as they have no space where to emerge. This requires surgery. One final point is that we are living longer so problems with teeth and other parts of the body are more likely to become more common. | [
"Because every mammal's teeth are specialised for different functions, many mammal groups have lost teeth not needed in their adaptation. Tooth form has also undergone evolutionary modification as a result of natural selection for specialised feeding or other adaptations. Over time, different mammal groups have evo... |
I've heard a lot about European colonialism and Imperialism on the indigenous people of the Americas but what about Russia's interactions with indigenous people as it spread to the Pacific? | Hey, great question. The period that you'll be most interested in extends from 1558 to 1819 and from the Ural Mountains to what is now British Columbia in North America. During this time, Russia expanded across Siberia to the shores of the Pacific Ocean. Faced with an immense ocean obstacle, the Russians drove themselves onward, crossing that ocean and establishing themselves upon what is now known as Alaska. They drove still further, establishing trading posts in California and Hawaii.
Throughout these 300 years, one thing principally drove Russian expansion: **furs.**
As the Stroganov Chronicle states:
> "Then through God's grace the Muscovites and the cossacks ... became very wealthy from trading in furs, and they lived in joy and happiness, thanking Almighty God for having given the Sovereign such rich land."
It was fur wealth that encouraged the eastward advance. Furs were valued in China, and Chinese goods were valued in Europe. The Treaty of Nerchinsk in 1689 settled the Russian-Chinese boundary to a large degree, and it also created the trading city of Kiakhta, located directly on the Russian/Chinese border in the middle of Siberia. It was here that the Russians carried furs, and from here that they carried Chinese goods on an immense transcontinental journey to Europe.
Enormous amounts of money were made from furs, and this led to overhunting, which in turn led Russians to constantly look eastward and eventually to North America. 1558 is the year that Tsar Ivan Vasilevich granted Grigorii Stroganov financial, judicial and trade privileges along the Kama River to the east of Kazan.
This claim brought the Stroganovs into conflict with Kuchum Khan, a descendant of the Mongol Empire who held a shaky dominion over a large portion of Siberia. In 1581, the Stroganovs funded a band of cossacks led by Ermak Timofeev. Ermak's cossacks crossed the Urals and conquered huge swaths of land, and even though Ermak and most of his party were killed, Stroganov reinforcements held much of the terrain they took and implemented a procedure of conquest and tribute that would extend to North America.
Even today, Siberia is lightly settled. Between 1581 and the end of the 18th century, this was true even more so. Instead of outright control of a particular piece of (otherwise valueless) terrain, Russian authorities set up a system of tribute called the *yasak*.
After the Stroganovs' success (and huge riches earned from tribute), the Russian government authorized other ventures across Asia. These operated much as the Stroganov venture did. A well-armed force would advance and defeat the armed forces of a tribe, khan or region. In turn, that defeated group would swear loyalty to the tsar and agree to pay a tribute to the conquering agency. That tribute might be paid in furs, gold, or other precious, tradable objects. In exchange, the armed force would agree to not kill (pretty much) everyone and restrict itself to petty corruption, extortion and massacre. If the group continued to resist, the Russians would fight them and convince the group's neighbors to pile on by pledging a share of the loot.
A beaten group might be forced to supply *corvee* labor for Imperial projects, or be forbidden to conduct diplomacy. It might be required to trade only with a particular trading company or trader. It would be required to follow the Orthodox church, discard other religions and give Orthodox priests and monks safe passage.
The Russians built a series of small forts *ostrozheks* and large forts *ostrogs* at strategic locations, not unlike what the United States would do in the 19th century. State employees and colonial officials would oversee this forcible tribute traffic and ensure the imperial government got its proper take. The *streltsy* (musketeers) provided firepower to back up the cossacks who did much of the conquering.
These techniques extended across the Pacific Ocean to Alaska during much of the 18th century. There, the prime fur was sea otter, but the Russians' inadequate naval skills meant they had to compete against the British and Americans for the fur trade in North America. Furthermore, the Russians were prohibited from trading at China's Pacific ports, while the other European powers were allowed.
The march of progress and the Enlightenment also put pressure on Russia to reform its practices. Catherine the Great formally forbade the practice of *yasak*, and Tsar Paul granted a monopoly in North America to the Russian-American Company in order to prevent some of the worst competition-driven offenses there.
It was not until the RAC's second charter was issued in 1819, and the company's American operations came under the authority of a naval officer, that the worst parts of the *yasak* came to an end. About the same time, the sea otter trade collapsed under the weight of overhunting, and the Russian government instituted some of the world's first environmental protection measures to allow the continued, sustainable harvest of Alaska fur seals.
The study of the Russian advance got a lot of fuel in the 1970s and 1980s, during a period of *detente* between the Soviet Union and the United States. The Oregon Historical Society in particular deserves a great deal of credit for translating some 3,000 pages' worth of Russian documents into English in the last five years of the 1980s. These documents were published in a three-volume set, and they're an incredible English-language primary source with the subtitle *To Siberia and Russian America*. There are plenty of popular works about the Russian conquest of Siberia, which was completed with the 1858 Treaty of Aigun. | [
"The Russian colonization of Siberia and treatment of the resident indigenous peoples has been compared to European colonization of the Americas, with similar negative impacts on the indigenous Siberians as upon the indigenous peoples of the Americas. One of these commonalities is the appropriation of indigenous pe... |
why do you often lose cellphone signal in stairwells? | Most stairwells are made of brick or cinder block. Often times, the steps themselves are made of cement. Wireless signals do not easily travel through these materials. | [
"In areas where signal reception would normally be strong, other factors can have an effect on reception or may cause complete failure (see RF interference). From inside a building with thick walls or of mostly metal construction (or with dense rebar in concrete), signal attenuation may prevent a mobile phone from ... |
how to blind differentiate different denominations of currency? | Canadian notes feature [braille](_URL_0_) on them to allow people to tell the difference | [
"A study commissioned by the Bank of Canada in 1994 stated that about 8,000 blind Canadians do not benefit from the large numerals or distinct colouration of the banknotes. In 1990, the Bank of Canada, via the Canadian National Institute for the Blind, had begun distributing to these individuals a free electronic d... |
why do people make an "er" sound when thinking? | I've always heard it defined as a 'verbal pause'.
This Wikipedia link may help:
_URL_0_
Here's an excerpt I think will clear it up a bit:
Recent linguistic research has suggested that non-pathological disfluencies may contain a variety of meaning; the frequency of "uh" and "um" in English is often reflective of a speaker's alertness or emotional state. Some have hypothesized that the time of an "uh" or "um" is used for the planning of future words; other researchers have suggested that they are actually to be understood as full-fledged function words rather than accidents, indicating a delay of variable time in which the speaker wishes to pause without voluntarily yielding control of the dialogue. There is some debate as to whether to consider them a form of noise or as a meaning-filled part of language.
Speech disfluencies have also become important in recent years with the advent of speech-to-text programs and other attempts at enabling computers to make sense of human speech. | [
"Eh ( or ) is a spoken interjection in English that is similar in meaning to \"Excuse me?,\" \"Please repeat that\", or \"Huh?\". It is also commonly used as an alternative to the question tag \"right?\", i.e., method for inciting a reply, as in \"It's nice here, eh?\" (instead of \"It's nice here, right?\"). In No... |
Why do we accept differences in intelligence between dog breeds, but not human groups? | because dog breeds are not at all similar to human ethnic groups.
Dog breeds are the result of very intense artificial selection over a very short period of time (most dog breeds came about only in the last few hundred years). The breeds are well defined and distinct from each other for both of these reasons. The intense aritifical selection means that the genetic divergence was maximal for this short period of time, while the short time period means that the genetic lines of the different breeds are still fairly well-controlled and simple (i.e. there are few interbreed crosses within "purebreed society"). Not only that, but because the selection was for (mainly) appearance, temperment, and intelligence, these are obviously the factors in which most breeds differ from one another.
The evolution of human ethnic groups is a different thing entirely; much, much, much weaker selection, on many, many different traits, over a much, much longer time, with many, many "inter-ethnic" breeding events. We group the different ethnic groups based on cosmetic appearance, but because humans were NOT selectively bred in the same way dogs were, there is very little to link the genes that determine appearance with the genes that determine all of other things that vary from person to person.
Comparing dog breeds genetically, we find that within a breed, dogs are very similar to each other, and (fairly) different between breeds. In humans, there is far more genetic diversity *within* an ethnic group than there is between ethnic groups.
| [
"Both humans and dogs are characterized by complex social lives with rich communication systems, but it is also possible that dogs, perhaps because of their reliance on humans for food, have evolved specialized skills for recognizing and interpreting human social-communicative signals. Four basic hypotheses have be... |
how does a particulate mask/gas mask protect against radiation? | Nuclear fallout is radioactive dust returning to the earth after a nuclear blast has occurred. The air isn't radioactive, the particulate matter in the air is. Wearing a particulate mask prevents you from inhaling the radioactive dust. | [
"Airborne toxic materials may be gaseous (for example, sulfur mustard and chlorine gas) or particulates (such as biological agents). Many gas masks include protection from both types. Gas masks are used in construction to protect against welding fumes, in demolition to protect against asbestos or other hazardous pa... |
how could humans distinguish different voices pouring out from output device since it's just waves of compressions and decompressions? | ALL sounds and vibrations in nature are waves. Think about it, an atom cannot move instantaneously from one position to another.
So sound is just waves. But you can add how many waves you want of different pitch, phase, and amplitude, as you want, to create a unique wave. That's how all sounds are formed. | [
"A similar process has been created to aide people who have lost their vocal cords. This experimental device would do away with previously used robotic sounding voice simulators. The transmission of sound would start with a surgery to redirect the nerve that controls the voice and sound production to a muscle in th... |
Did medieval castles really have water filled moats? | Yeah sure! Like [that](_URL_0_) for example. But only when the castle was in the low lands near a river or at least at sea level.
On everything higher was no water. There were just no logistics to get that much water up. | [
"A moat was a defensive ditch with steep sides, and could be either dry or filled with water. Its purpose was twofold; to stop devices such as siege towers from reaching the curtain wall and to prevent the walls from being undermined. Water moats were found in low-lying areas and were usually crossed by a drawbridg... |
do cars use up petrol due to speed or rpms? | RPMS and the motor curve matched with the transmission. Motors are more efficient at certain RPMS. Along with the load on the engine. Steep hill vs flat ground. To check the load vs certain gears and rpms you need exhaust temp. Lower temp is better and more efficient less fuel being blown out. | [
"Engine RPM seemed to be more a function of accelerator pedal position than of actual road speed. \"Flooring\" the accelerator pedal would cause the engine speed to flare (even though there is no automatic downshift and no torque converter lockup to disengage). As the car would accelerate, RPM would further climb, ... |
What was the German language known as before the creation of the modern Germany | I'm not sure what you mean by the creation of modern Germany.
The first unified German state was the German Empire formed in 1871, and before then I don't believe the German language was vastly different from its modern incarnation.
Can you clarify the question, please?
EDIT: Misread. I thought you asked what it was LIKE before the creation of modern Germany. As for what it was called...German. The IDEA of a national German identity and ethnicity existed before there was an actual German state.
You'd probably have to go back quite a while to find it called something other than German, and by then I'm not sure it would be recognizably German, anyway. | [
"Modern German begins with the Early New High German (ENHG) period, which the influential German philologist Wilhelm Scherer dates 1350–1650, terminating with the end of the Thirty Years' War. This period saw the further displacement of Latin by German as the primary language of courtly proceedings and, increasingl... |
I just finished reading Shogun by James Clavell and I have some questions about the historical events that followed the Battle of Sekigahara | Christianity was banned, and people were usually registered to Buddhist temples through the danka system.
Missionaries/Jesuits were absolutely not allowed to stay in Japan, and would be killed if found out, especially if they had an underground church.
The Japanese era of Sakoku (closed off country) was created in order to banish Christians/barbarians from influencing Japanese religion and politics, and to control Japanese trade by preventing unfair treaty ports from forming across Japan. Japan instead created their own port, Dejima, which they limited to only trade with the Dutch. There was however trade with Korea/China going on at this time.
The borders/international trade with Japan and the rest of the world were opened by Matthew Perry and his black ships, an American. This preceded the Meiji era.
| [
"The 1585 was one of a series of assaults made by Toyotomi Hideyoshi against the Ikkō-ikki religious zealots towards the end of Japan's Sengoku period. This battle followed the siege of Negoro-ji, in which Hideyoshi's forces burnt a temple complex to the ground; a number of the Saiga Ikki zealots escaped to nearby ... |
Is getting 8-9 hours sleep long enough for a quality sleep, or are there other factors that should be taken into consideration? | There are other factors that should be considered when talking about sleep. One of the big ones is pretty obvious: age. The National Heart, Lung, and Blood Institute has the [following chart](_URL_1_) that lists the suggested length of sleep by age group. Sleep is an interesting topic, because we still don't quite know why some people operate really well with less than the recommended 7 to 8 hours of sleep, and why some people need slightly more. Some people think it may be genetic. Others think it may be due to individual differences in our circadian rhythms.
Naps are an interesting part of sleep as well, since they're usually a lot shorter than our standard sleep cycles, and yet they increase our cognition and performance. [Numerous](_URL_2_) [studies](_URL_3_) [have](_URL_0_) looked at the effects of naps and performance. It appears that the act of falling asleep seems to activate certain neural mechanisms, such as memory consolidation, or reverse hormonal imbalances caused by a limited amount of sleep, essentially sort of "resetting" your circadian rhythm.
James Maas from Cornell has done a lot of research on sleep. If you have the time to spare, I highly suggest picking up one of his two books on sleep (Sleep for Success! or Power Sleep). | [
"BULLET::::- Infants (Birth to one year) are recommended to have 14 to 17 hours (for those aged 0-3 months) and 12 to 16 hours (for those aged 4-11 months) of good quality sleep, including naps during the 24 hour period.\n",
"The National Sleep Foundation cites a 1996 paper showing that college/university-aged st... |
Is gravity the same throughout the earth? | Gravity differs all over the planet.
[Here](_URL_0_) is a link to a seafloor gravity anomaly map. The accompanying article explains a lot about why gravity varies (rock densities, and the amount of mass between you and the center of gravity) as well as what such anomalies tell us about geologic structure.
| [
"The gravity of Earth is the acceleration that is imparted to objects due to the distribution of mass within the Earth. Near the Earth's surface, gravitational acceleration is approximately . Local differences in topography, geology, and deeper tectonic structure cause local and broad, regional differences in the E... |
what is the strategy behind football players always running straight into the pack of opposing players, gaining just 2-3 feet? | Football is very much the game of inches. Rushing the ball is slow and takes a lot out of your players, but its consistent. You are going to gain yardage, and as long as you can get first down its progress. Throwing the ball is risky if its an incomplete pass there is no progress, and if your QB gets sacked you lose yardage. This isnt even considering the possibility of getting intercepted, which is an instant turn over. | [
"Players can run with the ball in any direction they want. However they cannot use a teammate to obstruct the opposition. This occurs when they run around or into one of their own players and in the process prevent a defender from tackling them. Defending teams can also run anywhere they want as long as they do not... |
Does electricity slow down as it moves along a wire (or other conductor)? | The main issue with long distance power transmission is that you don't get 100% transmission. A lot of electricity is lost to heat (and other energy) as the electricity moves down the wire.
Our grid isn't very efficient, and this is one of its big problems. | [
"The electrical resistance of a power line causes it to produce more heat as the current it carries increases. If this heat is not sufficiently dissipated, the metal conductor in the line will expand and lengthen, so that it sags between supporting structures. If the line sags too low, a flash over to nearby object... |
How much of pregnancy death in past ages is attributed to the young age of mothers? | A certain amount would have been due to the young age of mothers, a body being physically too small to give birth makes labour far more complicated. However in most instances girls would marry after puberty set in and should be physically prepared for labour.
Many deaths would have been caused by poor hygiene and poor medical knowledge. When Mary I of England was 'pregnant' it was believed that a boy would be born after 9 months and a girl after 10 months. Medical forceps were not invented until 1620, but as there was little knowledge of germs and infection these often did more harm than good; doctors were often reluctant to use them due to the associated risks. Princess Charlotte was left for days before forceps were used and eventually bled to death. Problems with infection, bleeding and pain contributed massively to maternal and infant mortality. | [
"The death rate for women giving birth plummeted in the twentieth century. The historical level of maternal deaths is probably around 1 in 100 births. Mortality rates reached very high levels in maternity institutions in the 1800s, sometimes climbing to 40 percent of patients (see Historical mortality rates of puer... |
order in which the body uses macronutrients or bodyfat as energy. | Overall, in general, the body "prefers" to draw energy from these sources in this order:
Glucose - blood sugar
Glycogen - stored carbohydrates in the liver & muscles
Fat
Protein - This is last not only because it's an inefficient conversion, but also because it's a desperation move, betting that you will find & eat food before your heart & /or diaphragm give out
Those are all being tapped all the time to varying degrees.
Losing fat takes one approach to eating & exercise *(calorie deficit, endurance exercise)*, building muscle requires a different approach *(slightly higher than maintenance calories, heavy on protein, and stressing the muscles)*. People who are out of condition can do a bit of both together at first, but as you get more fit the paths vary. | [
"The macronutrients (excluding fiber and water) provide structural material (amino acids from which proteins are built, and lipids from which cell membranes and some signaling molecules are built), and energy. Some of the structural material can also be used to generate energy internally, and in either case it is m... |
How can brain aneurysm acctually kill you? Isn't just a little blob that can cause some blood to leak? | A bleed from a brain aneurysm is called a "sub arachnoid haemorrhage" (SAH) and is a devastating and often fatal condition. The overall mortality is around 30%, with perhaps 10% of people dying before they reach hospital.
Although the aneurysm itself is just a "little blob", that is to say it is a localised distension or distortion in the artery, and may only be a few mm in diameter, bleeding from it can have catastrophic consequences. These consequences arise from the nature of the bleeding, and its location.
Firstly, bleeding from an artery is nearly always more serious than bleeding from a vein, because the pressure in the artery is much higher. This means there is more blood loss and its harder to control. To give an example, if a neurosurgeon inadvertently damages an artery during surgery, its an emergency; even with the artery exposed and the tools to hand,there may be substantial blood loss.
However, death from SAH does not occur from blood loss per se, but rather from where the blood is. Accumulation of blood in the brain tissue as a result of a bleed from a ruptured aneurysm can have numerous effects. First, there will be direct damage to the brain itself, arising from local pressure of the blood. If in a particularly vital area, like brainstem, this can cause almost instant death.
Second, the blood may rupture into the fluid filled ventricles of the brain. Here, it may clot, and prevent the normal drainage of cerebro spinal fluid. This leads to an accumulation of pressure in the brain, called hydrocephalus, which can itself be fatal.
Thirdly, the presence of blood in the brain tissue can irritate nearby blood vessel and cause them to constrict. This is called vasospasm, and usually occurs a week or so after the actual bleed. Severe vasospasm can lead to strokes, and potentially death.
Lastly, there are other non local effects of SAH that can be potentially fatal. These include heart failure, as well as changes in blood chemistry which if unrecognised can be extremely serious.
| [
"BULLET::::- Subarachnoid haemorrhage occurs when blood leaks out of damaged vessels into the cerebrospinal fluid in the subarachnoid space around the brain. The most common cause of a subarachnoid hemorrhage is an aneurysm rupture due to the weakened blood vessel walls and increased wall stress. The neurologic sym... |
Is it true Hitler was distraught when he watched The Great Dictator because he had always looked up to Charlie Chaplin and saw himself being ridiculed? | It is not true.
Well, it's not true in the sense that we have no unbiased, confirmed source stating that he ever saw it. A TV documentary said Hitler watched it twice, but Albert Speer says Hitler never watched it. No matter whether or not he watched it, there is no recorded reaction to the film. | [
"At an industry party Chaplin causes a minor scandal when he refuses to shake hands with a visiting member of the Nazi party. Fairbanks (with his health in great decline) comments that Chaplin looks a lot like Adolf Hitler, providing Chaplin with inspiration for his next movie in their final encounter before Fairba... |
Proton size problem? | Can you link to a claim that this must require new science?
In [this article](_URL_0_) from members of the CREMA collaboration from 2010, several possible explanations are offered:
> First of all we need to understand the origin of the observed discrepancy. It may be a computational mistake of the energy levels in muonic hydrogen or hydrogen, a fundamental error in bound-state QED, an unknown effect related to the proton or the muon, or a contribution which has been neglected. In addition it may be that the Rydberg constant, the most precise constant in physics, has to be slightly corrected.
| [
"The proton radius puzzle is an unanswered problem in physics relating to the size of the proton. Historically the proton radius was measured via two independent methods, which converged to a value of about 0.877 femtometres (1 fm = 10 m). This value was challenged by a 2010 experiment utilizing a third method, whi... |
if a neutron decays into a proton and electron, how do we know a neutron isn't just a proton and a electron together? | Well, ONE way a neutron can decay is into a proton + electron + anti-neutrino, sure.
But another way it can decay is into an anti-proton + positron + neutrino.
So is it made out of the firsts three, or the last three? It can't be both.
Actually, in this case, we already know a neutron is made out of even smaller particles called quarks. So it definitely can't be a proton + electron. | [
"Inside a nucleus, a proton can transform into a neutron via inverse beta decay, if an energetically allowed quantum state is available for the neutron. This transformation occurs by emission of a positron and an electron neutrino:\n",
"Inside a nucleus, on the other hand, combined protons and neutrons (nucleons)... |
why do older people not use the term "girlfriend" or "boyfriend" when referring to their so? | Because it sounds juvenile. A lot of people want to indicate that the person is their significant other, especially if they're not engaged (or if marriage isn't something they're into) and want the relationship to be taken more seriously than a couple of high schoolers.
I've never heard of two people in a committed relationship refer to one another as "friend", the most common term I hear is "partner" or "significant other." | [
"The term \"girlfriend\" does not necessarily imply a sexual relationship, but is often used to refer to a girl or woman who is dating a person she is not engaged to without indicating whether she is having sex with them. With differing expectations of sexual mores, the term \"dating\" can imply romantic activity w... |
why is it easier carry someone who has a tense body rather than someone who is dead weight? | If they tense their body, they will shift their weight close to you. All the muscles that your body uses to carry your own weight, can then be used to carry this other person.
If the person will just hang onto you, a lot of their weight will be shifted away from your body. It puts you out of balance, which your muscles have to compensate for (thus less strength to carry them). And most of their weight will be hanging lower, thus the largest and strongest muscle in your back (located at the top) won't be of much help. | [
"Carrying someone in this manner has several advantages over other methods of moving another person. The subject's torso is fairly level, which helps prevent further injuries. When the subject's weight is evenly distributed over both shoulders, it is easier to carry them for a longer distance – or more.\n",
"To g... |
Why in some countries people greet each other with kisses in the cheek? Where this tradition comes from? | follow-up question as I'm just returning from Belgium but met with Dutch nationals as well...:
how did the regional variations come about? in Belgium it is one kiss on the cheek. in the Netherlands it is three alternation kisses. secondarily, when - assuming this is a tradition that spread, rather than popped up independently in each place - did these variations manifest as culturally contingent practices? | [
"While cheek kissing is a common greeting in many cultures, each country has a unique way of kissing. In Russia, Poland, Slovenia, Serbia, Macedonia, Montenegro, the Netherlands, Iran and Egypt it is customary to \"kiss three times, on alternate cheeks\", but kiss twice in Bosnia and Herzegovina. Italians, Hungaria... |
why can't i just right click and download videos like i do pictures on the internet? | It depends. If the video is a raw html5 video then you actually can.
In general though what you are probably seeing is actually a flash movie, these play in a plugin and follow different rules.
Lately there has been significant progress in using JavaScript player systems to prevent download as well. You find these in YouTube's html5 player.
This is likely to become even more difficult in the future. With projects, like one I am involved in, using segmented video streams which makes right-click downloads not as simple as a picture.
Additionally, there is work in groups like EME that are working on integrating full DRM into the browser. I am firmly against DRM and think it is a bad idea but finding investors for a system without it is proving difficult.
As a result we may see DRM take over completely simply due to lack of funding for alternatives like mine. If that happens then I am truly sorry. | [
"The internet makes it possible for students to view videos of activities, events and places around the world. Viewing these activities can help English language learners to develop an understanding of new concepts while at the same time building topic related schema (background knowledge).\n",
"Some sites exist ... |
manual transmission and shifting | I can understand your excitement. Manual's are a lot of fun. But please use the search function.
_URL_0_ | [
"A manual transmission, also known as a manual gearbox, a standard transmission or colloquially in some countries (e.g. the United States) as a stick shift, is a type of transmission used in motor vehicle applications. It uses a driver-operated clutch, usually engaged and disengaged by a foot pedal or hand lever, f... |
How did the Royal Navy recruit new sailors in the Napoleonic Wars? | There were volunteers in the royal navy as well - especially skilled craftsmen such as carpenters, barrelmakers and ropemakers could make a decent sum working on a royal navy vessel, and the workload and food was usually better aboard a warship than it was aboard a merchantman. However, much of the crew was indeed pressed into service (ie conscripted).
The law allowed the royal navy to press any sailor between the age of 18 and 45 into service in the royal navy. Press gangs were usually sent aboard merchant vessels and into the harbours and forcibly took sailors (and rarely, non-sailors) to serve aboard royal navy ships.
Having a severe manpower shortage, the royal navy routinely stopped US merchant vessels and searched them for British subjects during the Napoleonic war - and the royal navy often took a very liberal aproach to who was a British subject - if you were born as such, you were such, which meant that most grown US citizens qualified. Thus the royal navy pressed plenty of US citizens into service - which was one of the reasons for the War of 1812. | [
"During the Napoleonic Wars, the Royal Navy expanded to 176 ships of the line and 600 ships overall, requiring 140,000 sailors to man them. The Royal Navy could man its ships with volunteers in peacetime, but it competed in wartime with merchant shipping and privateers for a small pool of experienced sailors, so it... |
why has our culture come to see older things as being more authentic? | The idea is that these things have been validated by being tried for a while and not rejected. Some old things are rejected as silly (think: white polyester disco suits). Those that remain have "passed the test of time" and are now considered accepted and good. | [
"These reproductions and the values of authenticity presented to the public through artifacts in museums provide “truth”. However, authenticity has a way of also being represented in what the public expects in a predictable manner or based on stereotypes within museums. This idea of authenticity also relates to cul... |
What would have been the diet of people who lived in the region of Alexandria, Egypt, in the early to middle third century? | A lot of their food would have recognisable as Egyptian food today. Much would have also been recognisable to Egyptians of Pharaonic times. Dishes such as *ful medames* (stewed broad beans/fava beans) and *molokhiya* (green soup of mallow leaves) are considered national dishes for good reason - they have been eaten in Egypt for many thousands of years.
The foundation of the diet was grain (wheat and barley). This was eaten as bread, both flatbreads and thicker raised oven-baked breads, and in other forms such as bulgur wheat and porridges.
Vegetables included onions and leeks, a variety of greens (e.g., mallow, lettuce, radish/turnip greens), okra, cucumbers, a radishes. Legumes were very important in the diet, with broad/fava beans, lentils, and chickpeas all being important (black-eyed beans/peas are common today, but I don't know when these reached the area (they were domesticated in West Africa)). A variety of fruits were available, including dates, grapes, pomegranates, figs, peaches, quinces, and citrons and possibly lemons. And, of course, the olive. Nuts included walnuts, pistachios, pine nuts,
Dairy products such as cheese and butter were eaten. Other animal products in the diet included eggs, a variety of seafood, and meat.
Oils included butter, and sesame, olive, linseed, and rapeseed (as a general term for *Brassica* oils) oils.
Flavourings/spices/herbs included garlic, cumin, coriander seeds, coriander leaves (cilantro), parsley, and that great ancient Mediterranean favourite, fish sauce (garum etc.).
Alcoholic drinks included beer and wine.
Key differences between their diet and modern food were the widespread use of fish sauce, lower average meat consumption, no rice yet (rice would arrive a few centuries later), and no Columbian Exchange foods from the New World (the chilli and tomato being prominent today, and absent then). Sweeteners were honey and sweet fruits such as dates and raisins; sugar wasn't yet grown in the area (Egypt was a sugar pioneer in the region in the 8th century, and a major producer in the next few centuries). Cooking oil was relatively more expensive, so less deep-frying. And, of course, there were no modern processed pre-packed snack foods. | [
"The cuisine of ancient Egypt covers a span of over three thousand years, but still retained many consistent traits until well into Greco-Roman times. The staples of both poor and wealthy Egyptians were bread and beer, often accompanied by green-shooted onions, other vegetables, and to a lesser extent meat, game an... |
I assume the common ancestor of birds and man must have been sexual, yet we encode sex genetically in entirely different ways. How is this possible? | The common ancestor of birds and mammals would have been reptile-like. Most reptiles have [Temperature Dependent Sex Determination](_URL_0_).
It is thought that two modes of chromosomal sex determination (ZW in birds and XY in mammals) evolved separately.
[Here's an interesting article](_URL_1_) about the evolution of sex chromosomes, which has happened many times independently across the tree of life (in plants too!). It seems that there are similar patterns in any organisms adopting chromosomal sex determination-- for example, one chromosome always degrades over time (Y in mammals). | [
"Sex-linked traits are a little bit more complex because these recessive traits are carried on the genetic information which determines the gender of a bird. These genes are usually referred to in simplified terms as X and Y genes. In mammals, it is the male that determines the sex of their offspring, in that mamma... |
Possibly a dumb question but here we go; There have been multiple female absolute monarchs in history who had total power over the laws, why didn’t they just make total gender equality laws and then enforce them? | **Short answer:**
Not a dumb question-- it's one whose answer gets to the heart of medieval and early modern ideas about political power. Don't assume that "people then" thought like "people now", or that power was ever really absolute.
**Discussion:**
Variations of this question have been asked before. You make an assumption
> "**There have been multiple female absolute monarchs in history who had total power over the laws"**
. . . that’s too strong as regards your example Elizabeth I-- and it's not easy to think of many queens with the power you suggest. Mary certainly does have an authoritarian inclination-- but that's with the support of a large Catholic constituency; she could do some things she wanted to do, but not "anything she wanted". Her "bloody" impulses were part of the Wars of Religion-- not something she thought up on her own as a whim.
Queen Elizabeth I was not "absolute monarch" and did not have "total power over the laws". She was a Queen with a Parliament and a hardly supine nobility-- they could and did push her to do all sorts of things she didn't want to do, and there were clearly things she might have wanted to do, but couldn't do. This particularly affects her personal life, where she seems to have had her desires for partners, but was pressed to consider marriage to people she wasn't interested in by others.
One can find female monarchs with power in history -- but its hard to find "multiple female absolute monarchs" with the "total power" you suggest. It is unusual to find any monarch who vastly liberalizes a social order by decree-- Alexander II freeing the serfs comes to mind, but there aren't that many examples, and it's not clear that monarchs possessed the power to change social custom against prevailing values. The most dramatic liberal reordering of a society by a monarchy might be the Meiji Restoration, but this was only nominally at the "Emperor's command" -- and they had to fight a war to accomplish it. \[Edit: I should have mentioned Peter the Great here, an even more dramatic example, but the Tsar's power is quite different from what you see in Western Europe-- and his reforms did produce a rebellion, the Streltsy Uprising of 1698, good evidence that there were bounds to the power of even the most powerful monarchs\]
Moreover, you assume that Elizabeth's view of a woman's place would naturally conform to contemporary notions of equality-- there's no reason to think that. In the celebrated Tilbury speech -- accepted by most as authentic, though there are some skeptics among scholars- Elizabeth was reported to say
> I know I have the body of a weak and feeble woman; but I have the heart and stomach of a king, and of a king of England too, and think foul scorn that Parma or Spain, or any prince of Europe, should dare to invade the borders of my realm: to which rather than any dishonour shall grow by me, I myself will take up arms, I myself will be your general, judge, and rewarder of every one of your virtues in the field.
Elizabeth's idea of gender and her idea of her own royal status live in quite separate compartments; she is a king who happens to be a woman; she is not a modern feminist-- we've no sense that her ideas about women were much different from her contemporaries.
For more on this topic see answers to previously asked questions
[Was Queen Victoria reacting to a specific group when she said that "feminists ought to get a good whipping"? Why did she have so much hatred for feminists?](_URL_0_) \- where u/sunagainstgold has the very nice discussion of the complexities of women on the throne.
and
[Considering their history of prominent female monarchs, how did the British justify denying women the vote?](_URL_1_)
\-- where I discuss Elizabeth and have a bit about Ernst Kantorowicz and ideas about the nature of a King or Queen. | [
"Some countries however accepted female rulers early on, so that if the monarch had no sons, the throne would pass to the eldest daughter. For example, Queen Christina of Sweden succeeded to the throne after the death of her father, King Gustav II Adolf.\n",
"Some countries, however, accepted female rulers early ... |
Did the King of France actually control Avignon during the Avignon Papacy? | Avignon was formally part of the Kingdom of Arles when the various popes lived there. Arles was independent from France and remained formally a part of the Holy Roman Empire. It was culturally distinct from the north in many ways. However, despite the formal distinction of the region, it was basically settled that the King of France controlled the region, even if not legally. The last pope to try to claim power over the King of France by excommunicating him (Pope Boniface VIII) wound up getting beaten in his home by French and Italian troops that the king had sent, which eventually led to his death. The next pope decided to absolve the King of France, and after him, the next pope (and the first pope to reside in Avignon) was a personal friend of the king. The reason Avignon was chosen over Rome was due to a similar conflict between the church and the Holy Roman Emperor, both of whom were vying for secular and temporal control. Avignon was seen as a safer area for the church, particularly due to the positive relationship with the King of France. The area surrounding Avignon was already owned by the church, and in 1348, the church purchased Avignon and united the two areas. | [
"The Avignon Papacy was the period from 1309 to 1376 during which seven successive popes resided in Avignon (then in the Kingdom of Arles, part of the Holy Roman Empire, now in France) rather than in Rome. The situation arose from the conflict between the papacy and the French crown, culminating in the death of Pop... |
is it possible through a birth defect for someone to be born with a super power? | What is your definition of a super power?
[Natasha Demkina](_URL_1_) claims to have x-ray vision.
[Al Herpin] (_URL_0_) says he hasn't slept in 10 years.
And [Veronica Seider] (_URL_2_) is said to have 20 times better vision than an average human.
If being able to do something that most others can't is a super power, then I'd say yes. | [
"If the mother is a carrier, and therefore one of her two X chromosomes has a DMD mutation, a 50% chance exists that a female child will inherit that mutation as one of her two X chromosomes, and be a carrier. If that carrier has a male child, there is a 50% chance that he will inherit the X chromosome with the mut... |
Why don't we use maglev launchers for spacecraft? | The advantage of maglev is that it's low-friction. You can reach top speed because very little slows you down.
They're not really remarkable to any degree besides that. Air still slows you down and air is the thing that space shuttles have trouble with. Sure, they'd make you use slightly less fuel at the very beginning, but that's not worth the cost of designing, funding, and building one for a small number of select missions. | [
"The Soyuz vehicles are used as the launcher for the crewed Soyuz spacecraft as part of the Soyuz program, as well as to launch uncrewed Progress supply spacecraft to the International Space Station and for commercial launches marketed and operated by Starsem and Arianespace. All Soyuz rockets use RP-1 and liquid o... |
what is a dead pixel and how would i get/notice one? | A dead pixel is one very very tiny dot on your screen that's either stuck black, or stuck one color. If you opened a giant white page and saw a black dot that wouldn't go away, or if you opened a giant black page and saw a red/green/blue dot that won't go away, that's a dead pixel.
Your monitor has millions of pixels in it, and it's really hard to manufacture that many tiny things without at least one being broken. So most monitor manufacturers have a policy about how many dead pixels are acceptable, above which they'll let you return it. Most of the time they catch this stuff on the factory line though, so if you see any they probably are below the threshold where they'll let you return it.
There are some techniques you can use to try to "fix" them, but i've not had much luck. Gently rubbing on the area, or displaying a rapidly flashing image under the dead pixel can, in theory, fix it.
Google image examples of a [dead pixel](_URL_0_) so you can see what they look like. | [
"Stuck pixels are often incorrectly referred to as \"dead pixels\", which have a similar appearance. In a dead pixel, all three sub-pixels are permanently off, producing a pixel which is permanently black. Dead pixels can result from similar manufacturing anomalies as stuck pixels, but may also occur from a non-fun... |
Why does osmosis not result in perpetual motion? | Wow, thanks for a thought-provoking question.... You got me to puzzle over this for a while. [Here's](_URL_0_) the best explanation I found online. (Make sure you read the "Why it won't work" part at the bottom.) There's a bunch of other websites too - people have been kicking around this idea at least since 1971.
A couple of things I learned: (1) the system cools down very slightly as the water column height originally rises. So you lose some heat energy right away. So even if there were no other issues, eventually the water would freeze. (2) hydraulics play a major role - there is no way to "wick" the water off the membrane at the high side without disrupting the weight of the high column so that it drops below the level that you need (see link above).
EDIT: had a wrong theory about an osmotic concentration, never mind!
It occurs to me that maybe this is why biology labs never demonstrate osmosis with a semipermeable membrane stretched across an entire beaker; instead they always do the demo with closed tubes that are not in contact with each other at the top end. | [
"As \"perpetual motion\" can exist only in isolated systems, and true isolated systems do not exist, there are not any real \"perpetual motion\" devices. However, there are concepts and technical drafts that propose \"perpetual motion\", but on closer analysis it is revealed that they actually \"consume\" some sort... |
During the Napoleonic wars did any high ranking officers serve with their men in the frontlines? | /u/BritainOpPlsNerf handled the notable cases but I'll handle the average day to day with exclusive respect to the French.
The most basic (ie: smallest) tactical body in the French military was the battalion. As in, the battalion of 840 men composed of a *voltiguer* (skirmisher) company, a grenadier (which I go over in some depth [here](_URL_0_) for what made them so special) company and 4 *fusilier* (ie: line) company's.
Each company post 1808 would have a total of 140 men separated into two "sections". These sections would be 3 rows deep and have a corporal on each of the 4 corners; a lieutenant would be in charge of each section and placed dead center in the rear. A Company Captain would be placed at the right of the 1st section (traditionally also to the right of the 2nd) and would lead from there.
With 6 companies creating a Battalion however there needed to be more officers above the rank of Captain to maintain the force. In this you would have two *Guide
Général*'s on either side of the line or positioned at the front and back of the column to, as is clear in the name, guide the battalion and keep it from breaking apart. There would also be an *adjutant* and a *sous-adjutant*, equivalent to a Major. One would control 2 *fusilier* Company's and the *voltiguers* and the other the other 2 *fusilier* Company's and the Grenadiers (traditionally). In the case of column formation one *adjutant* would be placed at the front and one at the rear. The leader of the Battalion, the *Chef de Bataillon* would remain on horseback between the two *adjutants*. His rank can be loosely compared to that of a Colonel in our English system. It should also be noted that these rank titles, *adjutant* and *Chef de Bataillon*, are used in the French military to this day.
Now it's easy to say that the *Chef de Bataillon*, or the "Colonel", just sat back as his men walked in and did all the fighting; you could not be further from the truth in this regard. The base of the French model of fighting was the column attack; it was the foundation on which Napoleon built his tactics behind. Through combined arms the infantry organized in line would hold the enemy infantry in place, the cavalry would threaten the flanks and force the enemy to commit his reserves, and then the French reserves would strike the weakest point with their full weight along with the *Grande Batterie*. By the very nature of a column attack the entire Battalion is at direct risk as it is an inherently aggressive maneuver that puts everyone there rushing into enemy fire and eventually into meeting them in a melee. So in that regard if you were in the Battalion and were in a column attack you were in direct danger and could never 'loaf about' as the rest of the men did the fighting.
So I'd say for certain the highest ranking man on the 'front line' would be a rough equivalent to a Colonel, the *Chef de Bataillon*, ie: the Battalion commander. If you mean the *literal* frontline that would be the Company Captain who was literally on the first rank of the front line leading the men.
-----
John Elting, *Swords Around a Throne: Napoleon's Grande Armée* | [
"Pierre Belon Lapisse, Baron de Sainte-Hélène (25 November 1762 – 30 July 1809) commanded an infantry division in Napoleon's armies and was fatally wounded fighting against the British in the Peninsular War. He enlisted in the French Army during the reign of Louis XVI and fought in the American Revolutionary War. A... |
what is the cancer rate for livestock, and what happens when we consume cancerous cells via eating meat? | The vast majority of cancers aren't transmissible by consumption. Your digestion breaks down the material anyway.
Also, cancer is something that tends to affect life forms that age longer. Animals that are raised for human consumption don't live very long. | [
"A 2016 literature review found that for the each additional 50g per day of processed meat (e.g., bacon, ham, hot dogs, sausages) consumed, the risk increased 4% for total prostate cancer, 8% for cancer mortality, 9% for breast cancer, 18% for colorectal cancer, 19% for pancreatic cancer, 13% for stroke, 24% for ca... |
Did any other countries in the 20th century with significant ethnic minority populations implement an equivalent of the "separated but equal" policy? | Poland had something a little like this for a bit. Jews were segregated in many areas, but still had legal rights. As in the US, they weren't actually equal, but the inequality wasn't as severe as in the Jim Crow era. | [
"In the 20th century, a few states passed, or attempted to pass, nationality laws, through efforts that share certain similarities. All took place in countries with at least one national minority that sought full equality in the state or in a territory that had become part of the state and in which it had lived for... |
How is meth different from ADHD meds? | Methamphetamine is actually prescribed sometimes for ADHD. Its drug name is Dexosyn. See: _URL_0_
The only difference between Dexosyn and street meth is purity and formulation (although to be fair, formulation is pretty important for determining the effects of a drug, and as u/CanaryBean pointed out the route of administration is also important). | [
"In both adults and children, ADHD has a high rate of comorbidity with other mental health disorders such as learning disability, conduct disorder, anxiety disorder, major depressive disorder, bipolar disorder, and substance use disorders.\n",
"ADHD is a neurodevelopmental disorder which is most pronounced in chi... |
What happens to rain/hail in and around a lightning bolt? | Interesting question. Rain water is basically distilled water (there are very minor impurities in it from particles in the air) and afaik does not conduct the electricity anymore than the air around it.
As for what happens to the precipitation around the lightning bolt, it gets vaporized into steam due to the intense heat.
I hope this answers your question.
EDIT: /u/just1nw A little ways down in the comments has done some more research into this, I recommend checking his comment out: _URL_0_ | [
"A typical cloud-to-ground lightning flash culminates in the formation of an electrically conducting plasma channel through the air in excess of tall, from within the cloud to the ground's surface. The actual discharge is the final stage of a very complex process. At its peak, a typical thunderstorm produces three ... |
why line breeding animals is considered okay, when most other forms of inbreeding aren't. | it's not considered okay to people who don't hold a double standard
inbreeding of dogs is famous for creating problem dogs, complete with medical issues
people keep "purebred" lines, but it's just them rationalizing shitty behavior | [
"Inbred strains (also called inbred lines, or rarely for animals linear animals) are individuals of a particular species which are nearly identical to each other in genotype due to long inbreeding. A strain is inbred when it has undergone at least 20 generations of brother x sister or offspring x parent mating, at ... |
curse_of_kintave's bestof'd comment explaining hipsters | Oddly enough, _URL_0_ of all places has the answer you're looking for: _URL_1_ | [
"Mark Greif, a founder of \"n+1\" and an Assistant Professor at The New School, in a \"New York Times\" editorial, states that \"hipster\" is often used by youth from disparate economic backgrounds to jockey for social position. He questions the contradictory nature of the label, and the way that no one thinks of t... |
how are stereotypes formed? | Human brains are basically always trying to predict things, and one of our major sources of data for predictions are the opinions of others. Unfortunately, other people aren't pure sources of information, rather their opinions are colored by the desire to believe their tribe or group is better than others. So they might make jokes or comments, based on no particular truth, that "feel good" because they lift the in-group and denigrate the out-group.
This information is taken as predictive data, and thus, prejudices form.
| [
"Stereotypes say about a fixed form or convention and also about something missing in individuality or originality. Human brain proceed the informations and then stores them in the memory, but there is a huge amount of informations it collects, that it is inavoidably to sort and then categorize them. Stereotypes ar... |
If we could travel at 99.9% the speed of light, it would take 4 years to get to Alpha Centauri. Would the people on the spaceship feel like they were stuck on board for 4 years or would it feel shorter for them? | Nope, time dilation is a cool part of special relativity. At 99.9% the speed of light the trip would be 0.17 ish years to the occupants of the spaceship. The closer you get to 100%, ie. add more 9’s to the end of your percentage, the faster the trip would feel to the occupants. Here’s a cool calculator site you can play with to see these effects. _URL_0_
-edit This seems to be a frequent question and it’s a good one. How would you age? The traveler would age relative to the time they experience. So on this trip while everyone on earth experienced 4 years, you’d only age a few months! Take a long enough trip and you might just outlive your own grandchildren!
-edit2 Time dilation has been proven experimentally using very precise measurements. Here's a link to an article for some further reading. _URL_1_
Also, as some have pointed out, it would take a long time to accelerate to these speeds at 1g and would require a HUGE amount of energy to do so. Definitely not practical with current propulsion technologies. I have heard that large solar sails might be able to accelerate small probes to high speeds 20-30% c which would be a cool thing to see.
-edit3 For those curious about the solar sail probe, if you google StarShot you’ll find a lot of info about it. _URL_3_
-edit4 As many have pointed out, time dilation is a direct result of the length contraction observed by the traveling body. Also, thanks for for the gifts kind strangers.
-edit5 Another fun link thanks to /u/konstantinua00 talking about relativistic effects on mission duration _URL_2_ | [
"The journey to Alpha Centauri B orbit would take about 100 years, at an average velocity of approximately 13,411 km/s (about 4.5% the speed of light) and another 4.39 years would be necessary for the data to reach Earth.\n",
"The fastest outward-bound spacecraft yet sent, Voyager 1, has covered 1/600 of a light-... |
Did the Soviets have anything similar to the U2 or SR-71? And did they fly over the US in the way the US did over the USSR. | [The question was asked and answered here.](_URL_0_)
> Yes and no.
They did have a U2 like plane in the M-55.
However Russia had issues spying on the US via planes. Problems the US did not have. That issue was the Atlantic and Pacific Ocean.
You have to understand the the Russia is a huge country that UNLIKE the US is bordered by a vast amount of land not all of which is friendly. The US is ocean locked on the east and the west while they have an ally and interconnected military with their northern neighbor Canada.
The US was able to send spy planes not just over Russia but would send planes that flew on the BORDER of Russia. They could do this because UNLIKE Russia the US had basses all along their border. In Turkey, Germany, Japan, and throughout the pacific. This made spying runs easy and more importantly not as fuel costly since you just took off and in no time bam your on the border ready to snoop. So spy planes where able to spy on the Russia with ease not ever entering foreign airspace.
On the other hand Russia would have to fly across the pacific, past all the detection rings in the pacific and somehow gets some pics before the jets arrived. The only other way was to go through Alaska and Canada which again good luck detection posts in Alaska as well as joint military bases in Canada will get ya.
Russia focused on Live intelligence gathering due to the openness of US culture while the US focused on physical intelligence due to its ease and the difficulty of penetrating a closed nation like the USSR. | [
"The Skunk Works had predicted that the U-2 would have a limited operational life over the Soviet Union. The CIA agreed. In late 1959, the Skunk Works received a contract to build five A-12 aircraft at a cost of $96 million. Building a Mach 3.0+ aircraft out of titanium posed enormous difficulties, and the first fl... |
Did the United States know of Russia's presence in the Americas before the Lewis and Clark expedition? | **Yes,** the expedition did know of Russia's presence, and so did the wider world. While the explorations of Russian pioneers like Chirikov and Bering were known among select audiences in Europe as early as the late 1740s, knowledge of Russian explorations was not initially disseminated widely due to the language gap and the generally lower level of discourse between Russia and other European nations. Russia and Spain, as the only two nations with firm presences in the Pacific Northwest until the 1770s, also had an interest in not widely publicizing their work. The British, as the insurgent power, had no such compunctions.
It wasn't until the accounts of James Cook's third voyage were published that knowledge of Russian possessions in the Americas became widespread, particularly in the English-speaking world. By the 1780s, and particularly after the Nootka Sound controversy of 1790, the English-speaking world was well-informed about circumstances in the Pacific Northwest.
In the 1780s, before even the Louisiana Purchase, and while he was serving in Paris as the American minister to France, Thomas Jefferson had extensive conversations with John Ledyard, a Connecticut man who served on Cook's third voyage.
Ledyard was the first American to circumnavigate the world (Cook's voyage began shortly after the Declaration of Independence, but Ledyard had not yet learned of it before the voyage began), and he was a strong advocate of the notion that the United States should explore the Pacific Coast because, as many Americans believed at the time, the United States was destined to span the entirety of North America and possibly South America as well.
"I wish to be on the coast before them (the British)," Ledyard wrote in 1785, "for they are the worst people in the world to follow in commerce or colonization among an uncivilized people."
Ledyard was foiled in his attempts to charter a ship for a mission from France to the Northwest, but in early 1786, [Jefferson suggested an alternative plan](_URL_0_): "I suggested to him the enterprise of exploring the Western part of our continent by passing thro St. Petersburg to Kamschatka, and procuring a passage thence in some of the Russian vessels to Nootka sound, whence he might make his way across the Continent to America."
Ledyard took up that idea, and he traveled across all of Eurasia, reaching Okhotsk, Russia's principal Pacific port, in 1787. During his travels, however, Russian officials became suspicious and believed that Ledyard was a spy. With the approval of Catherine the Great, Ledyard was arrested, declared *persona non grata* and deported from Russia via Poland. By 1789, he was exploring the Nile and drafting plans to explore North America from the east (via Kentucky) when he died of a disease caught in Egypt.
James Zug's ~~*American Traveler: The First Bicoastal American*~~ *American Traveler: The Life and Adventures of John Ledyard, the Man Who Dreamed of Walking The World* is the fourth and most recent biography of Ledyard, and I'd encourage you to pick it up if you get a chance. It's a fun read, as Ledyard led an incredibly fascinating life. I've used some of it to write this reply.
Despite Ledyard's struggles, American interest in the Pacific Northwest continued. The Cook missions had proved that there was enormous money to be made in the sea otter pelt trade with China, and in 1787, John Kendrick's *Columbia Rediviva* and Robert Gray's *Lady Washington* left Boston for the Pacific Northwest to participate in that trade. Both ships and both captains became involved in the Nootka Sound controversy, but both also became marked in history for their accomplishments on the voyage. Kendrick returned to Boston in 1790, having completed the first American-flagged circumnavigation of the Earth. Robert Gray, meanwhile, made the first confirmed discovery of the Columbia River, giving the United States a firm territorial claim on the Pacific Northwest by right of discovery.
At the same time the two were in the Pacific Northwest, the U.S. War Department attempted to coordinate exploration parties to the West, but these fell apart for various reasons. In 1790, a mission coordinated by a Lt. John Armstrong fell apart because of the difficulty of the challenge, and a subsequent mission led by a French naturalist was discontinued because the naturalist fell afoul of Federalist reaction to the French Revolution.
From 1795 to 1797, James Mackay and John Thomas Evans explored up the Missouri River, drafting maps and documents that would later be used by Lewis and Clark on their own expedition. I suggest Wood's *Prologue to Lewis and Clark: The Mackay and Evans Expedition* if you're interested in this "Lewis and Clark prehistory." At the same time, Alexander Mackenzie was traversing North America from Montreal, reaching the Pacific Ocean in 1793. His journals were published in 1801, and they provided another incentive for the United States to conduct an expedition.
When Jefferson was elected president and approved the Louisiana Purchase, he then had the means, motive and interest to put together an expedition that would have both the strength and the resources to travel across North America, then return. That expedition did not travel without predecessors, and it did not travel into a vacuum.
| [
"In 1788 the Spanish made contact with the Russians in Alaska for the first time. An expedition by Esteban José Martínez and Gonzalo López de Haro visited several Russian settlements. Their westernmost visit was to Unalaska. On August 5, 1788, they claimed Unalaska for Spain, calling it \"Puerto de Dona Marie Luisa... |
why are bi-racial, partially black people considered black? is it just racism? | The traditional rule is the "one drop" rule. That is, if you have one drop of "black" blood then you have been "contaminated" and are now non-white and thus lesser.
Obviously we have largely moved away from that sort of thinking. And I am in no way advocating it! But the memory of it is still alive and well.
Part of that means that it's going to be a lived experience for folks who are bi-racial. That's part of how the memories and experiences are kept alive and well. | [
"A way of classifying someone by looking at their physical appearances, like skin color, nose shape, lip size, etc. and choosing their race based on what they look like. Doyle and Kao (2007) said biracial individuals (black/white) felt more keen to identify as black because of the process of physiognomy, in compari... |
What are the risks associated with microwaving plastics? | I have had a thousand arguments with biologists on AskScience on this issue, and I'm tired of engaging in this argument, so I will limit the scope of my claims to this: My understanding of the topic is that there are some biological studies which claim the leaking of certain small molecules, like bis-phenol A from polycarbonate, which may be toxic (I'm not a biologist, I can't comment on toxicity). [Given the very very slow diffusion of small molecules inside polymers](_URL_0_), my back of the envelope calculations indicate that at high temperatures, and therefore also for room temperatures, it would take at least several hundred years for you to drink a lethal dose of (say) bisphenol-a from your Nalgene bottle assuming that the bottle is 99% polycarbonate and 1% BPA (mass percents, would be a horribly, horribly inefficient polymerization and the material would probably also have terrible properties and be thrown away) and that you drink 3 full bottles a day, assuming 100% solubility of BPA in water and that BPA 100% bioaccumulates.
Therefore my claim is this: Biologists seem to be claiming that potentially toxic small molecules are leaking out of plastics. If this is true, I would be concerned, but no one has yet explained to me how its possible that these small molecules are actually getting out of the plastic and into the water.
FWIW, I'm qualified to speak to the polymer dynamics of this issue as polymers are one of the most visible examples of glassy materials. | [
"There is ongoing concern as to the use of plastics in consumer food packaging solutions, environmental impact of the disposal of these products, as well as concerns regarding consumer safety. Karin Michaels, Associate Professor at Harvard Medical School, suggests that toxins leaching from plastics might be related... |
how is congress legally allowed to hold committee to pass legislation in a closed manner? | So, I'll answer each question in succession:
(1) How is this legal?
It's important to bear in mind that what the conference committee does is, essentially, compare the House and Senate versions of a bill, hammer out the differences, and create a new piece of legislation which *then* has to be passed in both the House and Senate again. Basically, even after passing the same *basic* bill, they have to pass the same *exact* bill for it to become law. The conference committee does not *itself* pass legislation.
So, it's legal because it's not actually passing legislation, it's just a bunch of Congressmen and Senators sitting down and saying "what should the combination of these bills look like". They *cannot* do the final vote on the final bill in secret.
(2) Has this ever happened before?
All the time. Most of the time it happens in open-door sessions because no one gives enough of a damn to pay attention, but as the entire practice is a creature of the rules of the House and Senate, it (a) has happened before, and (b) could be done with every bill.
(3) Do the American people have any recourse?
Well, first, recourse from what? We'll all be able to read the final bill before it goes back to the House or Senate, and be able to voice our objections to the final language.
Second, no. As a general rule, the American people do not have standing to bring any kind of suit against Congress or the Senate for procedural issues. Our recourse is in the ballot box. | [
"In the House of Representatives of the US Congress, motions to suspend the rules are in order on Mondays, Tuesdays, Wednesdays, and during the last six days of a session. The Committee on Rules normally releases a list of bills and resolutions to be suspended for the week as were requested by the various committee... |
Relative to the Earth's environment, how bright would Pluto's landscape appear if you were standing on the sunny side? | Pluto receives about 1/1000th the sunlight that Earth does. So, it would appear pretty dark. However, it would be significantly brighter than it would be on Earth at night during a full moon. | [
"During its 2012 close approach to Earth, had a brightest apparent magnitude of about 13.9, making it about as bright as the dwarf planet Pluto. By 25 February 2012, it had dimmed to magnitude 30. During its close approach of on 28 January 2014, it will only reach a magnitude of about 23. has been observed in more ... |
When an electron orbits a nucleus is it something similar to how a satellite orbits the Earth, or is there some other mechanism propelling it? | It is extremely difficult to visualize the orbit of an electron. It can't be thought of in the classical sense (i.e., an object orbiting another object). Instead, you have to describe it's motion using quantum mechanics.
QM tells us that the electron will occupy a "cloud". We don't know where the electron is, but it is likely somewhere in this cloud.
The reason it doesn't fall into the nucleus is because electrons can only occupy certain energy states (Neils Bohr showed this). There will be ground state, which is sort of like the lowest possible orbit that the electron can exist in. The electron can't loose anymore energy in this state, and therefore, won't go crashing into the nucleus. | [
"Only orbits that begin and end at the nucleus are important in closed-orbit theory. Physically, these are associated with the outgoing waves that are generated when a tightly bound electron is excited to a high-lying state. For Rydberg atoms and molecules, every orbit which is closed at the nucleus is also a perio... |
I'm currently listening to the Cast Recording for the musical 'Hamilton'. What historical liberties does it take that I should be aware of? | At the risk of submitting a less-than-in-depth reply, I'll highlight two major inaccuracies in the hopes that someone more knowledgeable about Hamilton (though perhaps not the musical) can expand upon them -
1) *The Farmer Refuted*. In the musical, this is depicted as a debate in the street, with the original author reciting from a manuscript while Alexander Hamilton repeatedly interrupts. In actuality, this was a written rather than verbal disagreement, and Hamilton's responses were published anonymously as two essays - "The Farmer Refuted" and later "A Full Vindication of the Measures of Congress".
2) *The years of activities leading up Hamilton writing The Reynolds Pamphlet*. Here is probably where Miranda takes the most liberties with the historical record, for what I think are very good dramatic reasons. In the play, Jefferson, Madison, and Burr confront Hamilton in person about his financial improprieties. Hamilton shows them all the letters, clears his name, and then decides to author the pamphlet based on his distrust of the three men.
In actuality, Hamilton provided the letters and information regarding his affair and subsequent extortion to James Monroe and Frederick Muhlenberg, who'd been tasked with investigating his improprieties under the Monroe Commission. Monroe then sent copies of the letters to Jefferson. (Another Democratic Republican, John Beckley, is also speculated to have copied the letters.) In a 1796 essay (whose name escapes me) Hamilton made thinly-veiled references to Jefferson's own infidelities, and was rebuked a year later with references to the Reynolds allegations published in James Callender’s *The History of the United States for 1796*. It was a mixture of truths and falsehoods that put Hamilton in a rough spot - he had to rebuke the charges of embezzlement and treason, but couldn't rebuke all the charges of financial impropriety. So he wrote the pamphlet, which was widely disseminated by his enemies (represented in the play by Jefferson and the other Democratic Republicans showering the stage with the pamphlets, like dollar bills in a music video's strip club scene).
Ron Chernow has made some reference to this particular change in a [New Yorker article](_URL_1_) published earlier this year. Miranda and Chernow maintain that the active parties were changed and the amount of confrontations and back-and-forth condensed to a single meeting to avoid introducing too many unnecessary characters and to streamline the story. The second act takes actions of various Democratic Republicans and ascribes them to different members of the party (and/or Aaron Burr, when dramatically useful) in order to keep a focused narrative.
The rest of the changes are fairly standard stuff - years of correspondence condensed, several ongoing cabinet meetings condensed into one, etc.
Slightly off-topic but worth mentioning is the way the play handles historiography and cases in which there is missing evidence or conflicting narratives, such as the deal to move the capital ("The Room Where it Happens") or Burr's insistence just before the duel that Hamilton intended to shoot to kill (because he was wearing his spectacles). The author, Lin-Manuel Miranda, is both a fan and a friend of the author Stephen Sondheim, who's written several historical musicals, among them a piece called [*Pacific Overtures*](_URL_0_) (I've linked here to a production taped for Japanese television). The technique of having an entire song highlighting different accounts of the historical narrative, and making a point of saying "nobody knows the full account", can be traced to the Act One finale of *Pacific Overtures*, a number called "Someone in a Tree" that's considered in the musical theatre community to be of Stephen Sondheim's crowning songwriting achievements. Both musicals (Hamilton and Pacific Overtures) are concerned with not just the *story* of what happened, but about who tells that story, how we arrived at that story, what the historical record says, and how our perspectives and the perspectives of the people telling the story shape that history. In a sense, both musicals can be described as not just *historical retellings*, but *plays about the study and reconstruction of history itself*.
There's also another Sondheim musical that does this, *Assassins*, about various successful and unsuccessful assassins of U.S. presidents. The play is narrated by an all-American, midwestern balladeer who sings commonly-accepted descriptions of the assassins and their motivations (typically dismissing them as crazy and against the grain of American culture), while the actual depictions of the assassins show them as quintessentially American and of their time - they are not un-American, but toxic exaggerations of America.
All three musicals are excellent depictions of history as it's made, in contrast to historical musicals like *1776*, which tend to depict events and characters through a narrow focus, showing clear heroes and villains and glossing over inaccuracies, gaps, and conflicting narratives.
Source: Ron Chernow's biography of Hamilton, and also Meryl Secrest's hit-or-miss biography of Stephen Sondheim. | [
"The original Broadway cast recording for \"Hamilton\" was made available to listeners by NPR on September 21, 2015. It was released by Atlantic Records digitally on September 25, 2015, and physical copies were released on October 16, 2015. The cast album has also been released on vinyl. The album debuted at number... |
why was digital tv mandated through law in many countries? what is the real reason for the analog to digital tv conversion? | My guess is so that we could open up the old spectrums and take up less space because digital is easier to compress | [
"BULLET::::- 26 May – As part of a government trial to test the feasibility of switching the UK to digital television, Ferryside and Llansteffan, two towns in Carmarthenshire, have been chosen to become the first places in the UK to have their analogue signal switched off. Residents who do not currently have access... |
Why was the Soviet army able to win against the Kwantung Army in 1938-39, but was incompetent in the Winter War 1 year later? | Other factors helped the Soviets in the Far East.
First, the terrain: compared to heavily forested Finland with many lakes and rocky outcroppings breaking the terrain further, Manchuria was more or less open plain, perfectly suited for the Soviet mechanized combat technique and penalizing the Japanese, who had far fewer tanks. Had Finland's terrain resembled Manchuria's, it alone would probably have all but guaranteed a relatively swift Soviet victory.
Second, Japanese hesitation to escalate the conflict: apparently, the Japanese did not want an all-out war and refused to plan operations elsewhere along the Japanese-Soviet border. This allowed the Soviets to concentrate their best units at Khalkhin Gol, where the actual battle was taking place, without fear of Japanese counterattack elsewhere.
Third, leadership: even though the Soviet army was still reeling from the purges, the mastermind of Khalkhin Gol two-pincer envelopment attack (which trapped the Japanese 23rd Division and ultimately brought about a ceasefire) was Georgy Zhukov, later known as the defender of Stalingrad and a Marshal of the Soviet Union.
Nevertheless, it should be noted that the Soviets weren't happy with the performance of the Red Army: other battles than the final, decisive one had been more or less stalemates. Despite having very large advantages in technology, numbers, and firepower, the Red Army suffered huge losses, largely because of poor leadership. Therefore, the Soviet success was at best a qualified one.
However, this lesson came too late to have much influence in the conduct of the Winter War, yet alongside lessons from the Winter War, were likely very important for the Soviet military reforms that followed. | [
"As the Kwantung Army's fighting power diminished, it had to amend its operational plans against the Soviets accordingly. While the strategy for 1942 was the same as it had been in 1941, by 1943 this had been abandoned in favor of only one attack – either on the Eastern Front against Primorye or in the north agains... |
why are you sometimes able to eat a lot of candy or something sweet even though you cannot eat anymore of something fatty or savory, as if you have a second stomach for sweet foods? | I think it has something to do with the following - which is something I was reading about on a study into obesity awhile back:
Hard to believe, but from the study they realised the body ‘knows’ when you’ve ate too much fat and too much sugar, the brain just tells you you’ve had enough of each by making you feel sick or full.
The dangerous thing is when you eat foods that combine the both of then (a mixture of both fat and sugar). Mostly deserts. e.g Ice Cream and Cakes.
When you eat both with the recipe ingredients added as 50/50, the brain is unable to tell when you’ve had too much; they sort hinder the brains ability to work out if it’s full or not. That’s why you can keep eating and eating ice cream ( which usually is 50/50 ) and not really get too sick.
When the brain is hindered in this way, it’s quite a dangerous thing as it’s been making us ‘fat people’.
Edit: just found someone asking the same thing as you and they’ve also refereed to the same study. Might give you further reading:
_URL_0_ | [
"Even in a culture that eats sweets frequently, candy is not a significant source of nutrition or food energy for most people. The average American eats about 1.1 kg (2.5 pounds) of sugar or similar sweeteners each week, but almost 95% of that sugar—all but about 70 grams (2.5 ounces)—comes from non-candy sources, ... |
Why months, weeks, hours, minutes & seconds? | Circles are measured in units of 360(ish) degrees since the ancient times because
* 360 is an extremely convenient number, mathematically speaking — it's evenly divisible by every number from 2 to 10 except 7, and
* a year (which is an important agricultural cycle) has close to 360 days (which are an important human cycle)
Months are as long as they are because that's approximately the lunar cycle, which is closely related to tides (and therefore important in fishing and other maritime industries) as well as visibility of stars at night (and therefore important in navigation).
And because these natural cycles come in divisions of approximately 1:12 (year:month), 1:30 (month:day) and 1:360 (year:day), other time units were chosen historically to follow a similar pattern.
Early clocks (sundials) were based on movement of the sun in the sky, and therefore they were generally circular in shape, so they were also subdivided into 12s, 60s, and 360s.
Weeks similarly arose from approximate subdivisions of the lunar cycle, but since 7 is a very inconvenient number, that's the only place where it appears in calendars.
The fact that all these subdivisions are only approximations of cosmological cycles crops up in weird calendaring arrangements all the time — leap days, non-leap century years, and, perhaps the most hilarious of all, [September 1752](_URL_0_).
The reason why months alternate between 30 and 31 is that, well, all 30s doesn't work, and neither does all 31s, so we alternate. Year used to start on first of March (in Roman empire), which is why leap days are added to February — they used to be added as needed to the last month of the year.
This is also why *Sept*ember has in its name the latin root for *seven*, *Oct*ober for *eight*, *Nov*ember for *nine*, and *Dec*ember for *ten*.
So, months used to start in March, and go 31-30-31-30-31-30-31-30-31-30-31-28/29. Then, in Roman times, July and August were renamed from their previous names to their current names, in honor of Julius Caesar and Augustus, two roman emperors. And it was deemed totally uncool to have one of the emperor months be longer than the other, so August was lengthened to 31, and the pattern changed to 31-30-31-30-31-31-30-31-30-31-31-28/29.
(Separately, the beginning of the calendar then shifted to January, giving today's pattern of 31-28/29-31-30-31-30-31-31-30-31-30-31.)
Edit: added tangent about naming of months and pattern of month lengths; typos. | [
"What might loosely be called \"weeks\" are the divisions of days 1–7, 8–14, 15–22, and 23–30 of each month – two weeks of seven days followed by two weeks of eight. The Gatha days at the end of the year do not belong to any such week.\n",
"Time is measured in \"ọgán\" (seconds), \"ìṣẹ́jú\" (minutes), \"wákàtí\" ... |
when someone has a stroke, why do they lose movement, and why only on one side of their body? | My undertanding is that a stroke is generally caused by a blockage in a single blood vessel to or in the brain. The result if often brain damage but only on one side because the brain is split into two hemispheres that receive bloodflow seperately. Each half of your brain is in turn responsible for motor control of half your body. So damage on one side of your brain can result in loss of motor control on just one side of your body.
Another interesting example is something called "Alien Hand Syndrome" that can occur in people with the two hemispheres of their brain seperated. Surgery to do this intentionally is occasionally done as a last resort in some severe cases of epilepsy. The two halves of the brain can no longer communicate. A side effect of this can sometimes be one hand of the patient moving on its own without their conscious decision. | [
"A stroke is a decrease in blood supply to an area of the brain causing cell death and brain injury. This can lead to a wide range of symptoms, including the \"FAST\" symptoms of facial droop, arm weakness, and speech difficulties (including with speaking and finding words or forming sentences). Symptoms relate to ... |
how are music videos with multiple settings put together to make all the singing sync up together, or are they lip synced? | They record the song first and when they're filming the video they play the song in the background so the artists can lipsync over it, they'll do this various different times in different scenes and cut them all together for the final edit | [
"The music video uses \"duality\", as in \"light and shadow\" and \"virtual images and real images\" as the theme. Unlike previously released music videos, the scenes of them appear together are only a few and mostly are solo shots.\n",
"Throughout the video, various bright-colored animations and shots are shown,... |
Why do Kings go by just their first name, whereas modern heads of state tend to go by their last name? | Hi, the reason is that monarchs often didn't/don't have surnames. There's room for more contributions on this topic, but for now, there are a few responses in this old thread
* [What was the surname of English monarchs?](_URL_0_) | [
"It is not uncommon for monarchs to have a double first name. In some countries, only the first of the two names are counted when giving the ordinal, like in Sweden where the present king is called Carl XVI Gustaf, while in others the double name is counted as one name, like in Austria-Hungary (Franz Josef I was no... |
How helpful is mold? | It would be more human-friendly in that we would be free of the allergic, respiratory, and mycotoxin-related problems associated with mold.
However, as you mentioned, fungus is a necessary part of the decay process. Without it, dead plant and animal matter would continue to build up. Something similar to this happened during the Carboniferous period, when plants evolved to make wood and fungus hadn't yet adapted to decay wood. | [
"Buildings are another source of mycotoxins and people living or working in areas with mold increase their chances of adverse health effects. Molds growing in buildings can be divided into three groups — primary, secondary, and tertiary colonizers. Each group is categorized by the ability to grow at a certain water... |
why would the us gov have allowed or engineered the attacks on 9/11? | Individuals within the government. Unlike many other countries US politicians are allowed to own shares and the like and are given huge sums of money from businesses.
If you go to war certain businesses will make more money, such as those that make military goods. If you're in their pocket, have shares in them, etc you can make a lot of money.
So the conspiracy is that 911 was either engineered, or allowed to happen, by various individuals in the US government because they then could make a lot of money from it by spending tax payer money on the military, and companies that make military goods, and then they personally would end up with vast sums of that tax payer money in their bank account through shares, campaign contributions, and when they leave politics through being given jobs by these companies as a reward. | [
"The President, Federal Bureau of Investigation (FBI), Department of Homeland Security (DHS), and the National Counterterrorism Center (NCTC) are the most relevant elements of the U.S. government to the threat of American Islamic extremism and each has taken steps to address and counter the issue. Since 9/11 the go... |
why does it feel good drinking water after eating? | you are fulfilling the hypothalamus' (brain region) stimulation of thirst, so it feels good. your body just took in salt and other solutes, so in order to avoid osmotic shrinking of your cells, water must be taken in as well. | [
"The weight loss effects of water have been little studied, but it is plausible that consuming water with meals may reduce total energy intake and aid weight loss, particularly if water is taken instead of calorific drinks.\n",
"Drinking is the act of ingesting water or other liquids into the body through the mou... |
On a molecular level, how does a mirrors reflect light. (x/post from ELI5) | "A mirror is essentially a plate of glass coated with a thin film of metal, such as silver. At the atomic scale, metals are a crystal network of atoms whose outermost electrons dissociate and wander with high mobility through the network. These mobile “conduction” electrons are the source of electrical conductivity in metals, and when light attempts to penetrate a metal, they “vibrate in such a way” that an opposing electrical field is created, canceling the electric field of light and prohibiting any of its colors from entering beyond a few atomic layers. When that occurs, the light has been effectively reflected from the surface of the metal." [Source](_URL_0_) | [
"A mirror provides the most common model for specular light reflection, and typically consists of a glass sheet with a metallic coating where the significant reflection occurs. Reflection is enhanced in metals by suppression of wave propagation beyond their skin depths. Reflection also occurs at the surface of tran... |
why does a car battery quickly become dead if left directly on concrete? | Absolutely not an urban legend. I've seen it first hand | [
"BULLET::::- Automotive batteries stored on a concrete floor do not discharge any faster than they would on other surfaces, in spite of worry among Americans that concrete harms batteries. Early batteries might have been susceptible to moisture from floors due to leaky, porous cases, but for many years lead–acid ca... |
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