Very Interesting!

Here's an abstract of a paper describing skeletal evidence indicating that dental procedures consisting of the removal of infected tissue and the subsequent use of a mixture of bitumen and organic fibres as fillings were performed as early as 13 kya, with reference to even earlier findings.

While probably not the oldest technique, the use of splints for nonoperative treatment of fractures has remained largely unchanged. There is direct evidence that the ancient Egyptians used splints as they have been found in mummies and hieroglyphics. In fact they used quite intricate lower extremity splints made of bark or wood covered in a softer material and soft upper arm splints utilizing gravity as a form of traction which is similar to how they are used today.

https://pubmed.ncbi.nlm.nih.gov/21874991/

http://europepmc.org/backend/ptpmcrender.fcgi?accid=PMC2436247&blobtype=pdf

Well it would have to be something that would show up in a skeleton to qualify. Trepanning has been regularly done over wide areas of the planet for at least 7000 years so may be in the running. Though its probably not done for the same reasons today, its still an ongoing procedure.

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There are findings that Mesopotamians and Egyptians were pretty acquainted with anatomy and even performed craniotomies and autopsies. If we are talking about medicine as we perceive it, it would probably have to be Hippocrates. (approximately 400 BC) One example is his technique for realigning shoulder dislocations or draining ascites (fluid accumulation in the abdomen)

Three things.

1) To keep things like laces and trouser cuffs away from the gap at the edge of the moving steps where they might get trapped and pulled in.

2) To reduce the amount of dust and debris that makes its way into the mechanism. Some still gets through, though.

2) To help ground static charges that build up in the escalator during operation.

They are there to alert you through friction against your pants or legs that you are close to the edge. That way you can avoid getting pieces of clothing stuck in the crack between the side and the moving part.

They also keep the shoe laces away from this crack.

They most certainly are NOT to clean your shoes. In fact it is a terrible idea to try to clean shoes with it, because you need to take your shoes, laces and pants close to the edge and that defeats the whole purpose of those brushes.

EDIT: Howly caw! I am floored with all the positivity this comment has received. Thanks everyone. I am amused that of all the thoughtful comments I write on reddit, this one received so much traction. I am glad that all those who were using the brushes to clean their shoes now can do so with the knowledge of the risks.

They're to discourage you from standing too close to the sides where you or a piece of clothing could potentially get caught in the escalator.

Ok but for real, if they are to keep people away from the dangerous parts of the escalator, why did they invent them as something extremely fun to touch and jam your shoes into?

The brushes are a warning! Stay far away if you can. You don’t want to get something stuck between the edge or cracks in an elevator, like your shoe laces or long hair or some clothing.

Peanuts contain high levels of several heat-stable proteins, collectively known as Ara h proteins (from the scientific name Arachis hypogaea), that can act as antigens. Some people develop IgE antibodies against these antigens, which causes a peanut allergy. Sources: https://link.springer.com/article/10.1007/s11882-014-0429-5 and https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4451826/

In particular Ara h1 is quite stable, and the IgE-interacting epitopes can survive digestion.

This is why peanut allergies are more common than allergies to other legumes (e.g. peas).

Also as /u/DocWsky mentioned, peanuts are pretty common, so there are many opportunities for exposure.

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What is interesting is that USA and UK, where pediatricians used to be very careful instructing parents not to introduce kids to peanuts before they were much older, have some of the highest peanut allergy rates in the world. Israel has a baby food that is peanut based introduced to babies when first introduced to solid food. Some of the lowest rates of peanut allergy in the world. Not thought to be genetics based. But early exposure prevents allergy formation apparently.

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There’s a huge amount of research on treatments as well as vaccines. There are thousands of things being tested, ranging from drugs repurposed from other conditions (remdesvir, hydroxychloroquine) to traditional approaches (convalescent serum) to new drugs to completely experimental approaches. Clinicaltrials.gov shows over 1500 ongoing treatment trials, including

• Sofosbuvir/Ledipasvir and Nitazoxanide
• photodynamic therapy
• isotretinoin
• Ivermectin and Doxycycine
• Bemiparin
• Carrimycin

And so on and so on. And there are thousands of novel treatments in pre-clinical trial phases.

But in general, it’s much better to prevent than to treat. Vaccines can eliminate the virus from whole regions, they have much lower risks than most treatments, and they’re much better understood in terms of how to get from an unknown pathogen to a functional, effective vaccine, whereas treatments for viruses are hard to make, typically have lots of side effects, are often thousands of time more expensive, and don’t get used until the disease has started - so there’s more disease risk.

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It is much harder to treat somebody who is sick than to prevent infection. Imagine saying that instead of speed limits, safe road design, seat belts, air bags, and stop signs we would just find better ways to treat people injured in car accidents. Once your body has sustained enough damage it is hard to bring it back to normal.

A vaccine would protect those most at risk: immunocompromised, respiratory and cardiac history, elderly, etc. If we can keep people from getting sick in the first place, why wouldn't we? Especially with a virus that we don't know a ton about, we don't know how long some effects last (many people continue to have respiratory struggles). It would also help the economy a LOT. People wouldn't be missing work, insurance wouldnt be raising premiums to pay for hospital visits, everyone can get back to their normal lives. A big point is keeping people out of hospitals, which in some areas are not easily available, equipped, or affordable.

Prevention is much more cost-effective, and it also better preserves the quality of life for the patient.

Consider the following scenarios.

Effective treatment and no vaccine

1. You get infected on day 0.
2. You show no symptoms for 2 days. In the meanwhile, you spread the disease to 3 other people.
3. You start showing symptoms on day 3, and you dismiss it as a common cold. You walk around without a mask because it is the ultimate expression of freedom. You spread the disease to 30 other people.
4. You become really ill, and breathing gets difficult. You waited in line for hours at the crowded testing center. You infect 2 other people. You go home, and now you are bedridden for 7 days. This test costed your government or insurance company $200.
5. Your symptoms worsen. You need hospitalization. Your test result finally comes back positive. You are too fatigued to roll your eyes.
6. You are one of the lucky ones, and you recover in a month without having to be intubated. So, you conquered COVID-19. You pound your chest, and quickly regretted this gesture. Over the next few months, you have moderate breathing discomfort. Your treatment costed your government or insurance company at least $30,000. You paid $5,000 out of pocket.
7. In the meanwhile, there are now 35 other infected individuals, they go on to infect other people, and the cycle continues. About 20% of infected individuals will be hospitalized.

Total cost to you:
With 20% probability, you are hospitalized, and you suffer $5,000 and a month of lost wages (say, $4,000), totaling $9,000.
With 80% probability, you not hospitalized, so you suffer $0 (roughly speaking).

Total expected cost to you:
$9,000 x 0.20 + $0 x 0.80 = $1,800

Total expected cost to society per infected individual:
$34,000 x 35 x 0.20 + $0 x 0.80 + $200 x 35 = $245,000
(20% require hospitalization. 80% don't require hospitalization. Everyone does testing.)

Death toll: With new effective treatments, 0.8% of patients die. (See below for case fatality rate under current treatments.)

Effective vaccine and no effective treatment

1. You get vaccinated. This costed your government $20. You pay nothing.
2. In the next 6 months to a year, your chance of getting infected is reduced by (at least) 50%.
3. If you are infected, you go through the same process as in the above scenario.

Total expected cost to you:
$0 x 0.50 + $1,800 x 0.50 = $900
(As in the scenario above, you came too close to an infected anti-masker. You have 50% protection because you were vaccinated.)

Total expected cost to society per infected/protected individual:
$0 x 0.50 + $217,000 x 0.50 x 0.50 + $20 = $61,270
(We multiply by 0.5 twice, because we assume 50% protection for the people you meet; effectively, you would infect half as many people.)

Death toll: With no new effective treatment, 1% of patients die (current case fatality rate when hospitals are not overwhelmed), but infection rate is reduced by 50%, so the adjusted death rate is 0.5%. (This is a very conservative adjustment, as the pandemic would also end sooner, which would reduce the death toll further.)

Of course, with half of the population immune to the virus (at least temporarily), the pandemic also subsides. (Yes, there are anti-vaxxers out there, but let's hope most come to their senses at some point.)

​

Bottom line

With an effective vaccine, it costs you less, it costs society less, you suffer less, fewer people die, the pandemic ends earlier, and we return to normalcy earlier.

The mobile gaming market is sort of a wild west at the moment. Companies will pop up with some cheap garbage game that steals assets from more popular games, run misleading ads to attract as many gullible users as possible, then fold in a year or two only to form again under a different name and repeat the cycle.

Part of the reason why this happens is because of microtransactions and speed. The companies appear and disappear faster than legal action can be taken against them; a straightforward intellectual property suit might take a few years to resolve and by that time they have already gone out of business. Microtransactions mean that their misled customers are likely only out a couple of dollars at most so the authorities don't have much motivation to crack down on them very hard.

Ultimately they are doing it because they can get away with it.

You probably don't actually want to play the falsely advertized game. I looked up one of them where you move the pins to solve the puzzle. It's a real game, and you can download and play it. The problem is that all of the levels have to be hand-made, and they're not super difficult, so people just blow through them in a minute or two. As a result, the game devs FLOODED the game with ads. Like, you have to watch an ad multiple times per level. It's like, move a pin, watch an ad. Move another pin. People in the reviews talk about the game as being almost aggressively trying to make you stop playing the game in frustration, and they kind of are, because if you just played the content you'd clear the entire game in like 10 minutes.

EDIT: If you want to sit through the ads, the game is called Hero Rescue.

This was explored in a episode of.the Reply All podcast. Here: https://gimletmedia.com/shows/reply-all/rnhw23

Btw: These are the kind of ads I'm referring to.

Anybody miss paying for an app up front rather than this freemium BS? Also, I've reported them to Google and nothing ever happened. Google is a humongous and profitable company. If they wanted to nip this in the bud, they could. But as long as they get money out of it, it will continue to be a problem.

Fun fact: oxygen is so reactive with other elements that Scientists believe that without photosynthesizing organisms, free oxygen will not exist in any atmosphere for very long. One of the means we have considered analyzing exo-planets for signs of life is to spectroscopically look for free oxygen in their atmospheres. If a planet has a significant oxygen content in its atmosphere, it has something unusual going on chemically there that could indicate life.

Oxygen is unstable and reactive. If photosynthesising plants didn't keep replenishing it, we'd pretty quickly lose our oxygen to fires, aerobic respiration and so on. Our current equilibrium is around 21%, whereas back in the carboniferous the abundance of green plants and warmer temperatures would've lifted that balancing point to 35%.

A place to start is with the recognition that there is a reasonable level of disagreement with regards to the exact concentration of oxygen in the atmosphere through time and specifically the behavior of oxygen levels around the Carboniferous-Permian-Triassic interval. Specifically, Berner et al, 2000 used isotopic proxies and mass balance calculations to suggest that there was relatively rapid spike in oxygen levels up to ~35% during the Carboninerous and then a relatively quick drop down <20%, where as Lenton, 2001 suggests that it likely maxed out ~24% in the Carboniferous, and Glasspool & Scott, 2010 argue for concentrations ~30% for much of the late Paleozoic and into the Mesozoic but with more frequent oscillations in values. All of this is just to make sure we are all starting out with the right level of scrutiny of the numbers.

Most sources (those above, and others) agree that the rise in oxygen levels leading up to the Carboniferous is likely related to the large scale establishment of land plants. The controls on the decrease of oxygen (or even more generally, the relative roles of different biogeochemical processes on regulating oxygen concentrations in the atmosphere) are less clear. Processes that appear to be important in removing oxygen from the atmosphere are (1) oxidation of formerly buried organic matter, (2) reactions following thermal breakdown of buried organic matter, (3) the oxidation of pyrite (and other sulfur compounds) during weathering (see Berner et al, 2003 for a summary) and (4) a whole littany of other cycles that get more and more nuanced (e.g. Lenton, 2001 goes into these with a focus on the role of phosphorous cycling and Berer et al, 2003 runs through several as well). Generally, many of these appear to act as negative feedbacks, i.e. increasing oxygen concentrations drive some of these mechanisms to become more efficient at removing oxygen from the atmosphere, thus as far as I can tell from my reading, there is no single cause, but that generally a variety of biogeochemical processes (which are always active) would serve to bring oxygen levels back down after a spike. I'll happily be corrected by someone with more experience in these matters and who hopefully has some non contradictory sources.

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While there are several factors related to it, there are a few things to consider.

There were millions of trees during the carboniferous period that produced O2 from CO2, and used the carbon to make lignin, which is a very complex organic molecule that is a major component in wood, and is what makes it rigid and durable. At this point, there were no organisms capable of breaking down lignin, so when trees died they just piled up, sometimes sinking in swamps, and eventually formed coal deposits. This took the carbon out of the cycle but the oxygen built up in the atmosphere. After a while though, fungi developed enzymes that could break down lignin and use the carbon for their own biomass growth (most fungi use oxygen for respiration, like animals, and release CO2). The fungi released the CO2 back into the atmosphere and the food chain, and because there was such a large amount of lignin lying around as a useful food source, they had plenty of food to get through. Eventually because no more carbon was getting permanently locked up in coal (until humans started to burn it lol), an equilibrium was reached. It is important to remember that oxygen is also a component of CO2 and lignin, so oxygen was also going to those sources. Also when talking about the percentage composition of the atmosphere, it is relative to the other components. So oxygen levels of 30% vs 21% do not necessarily mean that 9% of oxygen was lost, it could just be that other components increased, making the relative amount of oxygen lower.

If you're in the second or third runner you'll have two transition points where you have to pass the baton. You aren't at 100% for both the start and the end of your 100m sprint. But if you're the first or last runner you only have one transition.

This translates to a longer segment of the race being ran at 100% for the first and last runners.

A team with their best runners running with less transitions will be faster because those faster runners can be utilized to their strength - running fast.

The first leg is run entirely in lanes and for most of this lap the runners will be separated by the stagger so there aren't interactions between athletes. The second leg runs 100m in lanes then breaks for the inside - this means there's an advantage to being clear of the other athletes at 100m into leg 2, which is mostly a factor of whatever leg 1 did. Otherwise it's possible for a faster runner to get boxed in and end up having to expend energy getting around other runners, while a slower runner will force others to go around. The next important point is at 200m in leg 2 - the order here is the order that the leg 3 runners line up on the track. Again, this is mostly a factor of the first runner's performance (they did 400m, leg 2 has only done 200m). There's an advantage to being in front at the exchange because it's easier just to run straight down the inside of the track than to look out for someone standing in the middle of the finish line. Sometimes runners miss the exchange or have to go out of their way.

By leg 4, the field has usually stretched out so overtaking isn't as hard and you're unlikely to be boxed in. Psychologically, it's easier to have a faster runner chasing down the others and/or able to extend the lead at this point. If you put the fastest runner on leg 3 and they're in the lead, they won't have the same target to aim for - they could finish that leg first, but you never know if they'd have found something else if they'd been up against the other faster runners in the last leg.

Extra energy is required overtaking people as you have to get in an outer lane which means you run further so it is best to get a lead and hang on to it. However 400m is also an endurance race and people under pressure can start off too quickly so a fast runner at the end can pick off those who are faltering towards the finish.

I always thought it was 1 of 2 reasons and depends who your against. If you put your fastest runner for the first leg the idea is to give the rest of the team that headstart so to speak with that fastest runner getting to the second leg runner fastest. But also you can have your fastest runner on the last leg to finish the race quicker to catch up or see off the last opponents in that final leg.

If you have your fastest runner as the anchor (last) runner, your 3rd runner may be more motivated to push themself when behind another team's 3rd runner, because of the belief that the anchor is fast enough to win the relay if not too far behind.

On the negative side, it is probably most demoralizing to have the lead for your last runner, but then lose the race, so to prevent that from happening you definitely don't have your slowest be the anchor.

Most of these answers are begging the question (repeating the question as if it is an answer).

Basically, people are just saying, "we form bonds with our pets because we form bonds with our pets" by saying "because they are cute and bring us joy!"

The actual answer is that most domesticated animals trigger our innate responses to tiny humans. The biological mechanisms in our brains that evolved to encourage us to protect and take care of babies and toddlers are triggered in the presence of certain cues, and over time we have selectively bred some animals to exhibit those cues for their entire lifetimes, and even moreso when they are a few weeks to a few months old.

Domestication is, in essense, breeding animals to remain in their infantile state.

SOURCE: https://blogs.scientificamerican.com/guest-blog/mans-new-best-friend-a-forgotten-russian-experiment-in-fox-domestication/

We've been breeding our go-to pet species for thousands of years. Over time, pets that seemed cuter to us were bred more often, creating cuter and cuter generations of pets (amongst other, more useful characteristics)

After, let's say, fifty thousand years of breeding, you can imagine there are some pretty cute pets.

Couple that with the breeding of animals in the last 800 years or so with the exclusive goal of creating the cutest breeds possible, these days you're basically helpless against the powers of cuteness that some pets have over you. They're basically genetically engineered to be adorable.

Edit: I'll add that in modern times I believe our propensity to think animals as cute has probably increased, due to less pests and threats from other animals. So we may think a lion is cute because we're not very likely to be killed by one, or have it eat our cattle. But many farmers in Africa absolutely hate lions and frequently poison them. So we're likely conditioned to see more animals as cute if they're not a nuisance or threat to us.

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Harley = loud on purpose. Engine is even built to be louder at the expense of efficiency and power. Others aren’t as loud

A lot of it is just for show, although many people argue that "loud pipes save lives" meaning it alerts people in cars and trucks to the fact that there is a motorcycle nearby.

There are many Japanese and German motorcycle manufacturers who make extremely powerful bikes that are very quiet.

Personally I ride a KLR650 which has a throaty thumping sound (single cylinder - they call them thumpers), but it's not really noticeable from more than maybe 100 feet away.

Both. Some people put louder exhaust pipes on their motorcycle on purpose. They believe it’s cool or they believe the extra volume will help alert drivers of their presence so they don’t accidentally run them over. But design also plays a role. Motorcycles are designed to be lightweight whereas the average car is designed for comfort. Cars are much heavier, so if you add a really nice muffler on it, it doesn’t have a profound impact on the overall weight of the car. A motorcycle might sacrifice sound dampening in order to reduce mass. Also a car’s engine is surrounded by the body of the car, dampening the sound further. Motorcycle engines are more exposed. Lastly, motorcycle engines rev faster than typical car engines.

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Every egg can become a queen (in most bee species). When a hive needs a new queen, a larvae is selected (sometimes more than one and they'll slug it out later) and fed nothing but "royal jelly." Royal jelly is made by workers (it's secreted by some gland on their heads), and while all larvae start on a diet of royal jelly, queens get nothing but that, while all other bees are fed "bee bread" after a few days of royal jelly (a mixture of nectar and pollen).

They just pick any of the cells that has an egg in it and then proceed to feed it royal jelly instead of the food the drones and workers get. If they are re-queening the hive they will usually do this to several cells so that they have several queens growing at once. Then, the first queen to emerge goes around and kills the other potential queens to establish her as the heir to the throne. Quite interesting process actually.

There are three kinds of bees in the hive.There is the Queen bee She is if course a female there is only one Queen in the hive her job is to lay eggs. She is the only female with developed ovaries. Queens are created by feeding the larva from a fertilized egg a diet of Royal Jelly. This will cause it's ovaries to develope. It will emerge as a fully developed queen bee. If the old queen is still healthy and virial she will leave the hive and a swarm of a significant % of the hives will leave with her to develope a new hive. The Virgin queen will depart the hive on her mating flight of which there maybe from 1 to 4 flights. If the old queen has used up all the sperm from her mating flight(s) 3 or 4 years previous she will be laying unfertilized eggs which will all be drones. The workers will raise a new quern when it hatches it will seek out the old queen (which will not swarm) . The new queen will kill the old queen. Then will proceed with her mating flight(s).

Worker bees. This is the type of bee that makes up the main population. Worker bees are all females. However worker bees ovaries are not developed. They are fed a diet of Royal Jelly for the first 3 days after hatching from a fetilized egg and then the diet is switched to honey and pollen for the rest of its larval period.

Drones. These are the male bees. There only purpose is to find a virgin queen to mate with They do not mate with a queen from thier own hive. Drones are incapable of stinging. They do not have a stinger. Drones do no work in the hive. They do not even have the ability to feed themselves. Drones are the result of an unfertilized egg.

When the hive wants to swarm or if it needs a new queen it will feed a fertile egg a diet of Royal Jelly.

Mating. Drones depart the hive daily at about noon. They just go out and fly about . When a virgin queen goes on a mating flight it also departs at about high noon. But when it does it flys away staying very close to the ground. This is to avoid mating with any drones (her brothers) from its own hive . When she has gone about a km or more from the hive she will fly up higher and higher. As she does any drone in the area will detect her smell (pheromone) and try to catch her. She will continue to fly higher and higher followed by a number of drones only the strongest will get to the queen and mate. When that occurs his genitailia will be ripped from his body with an audible pop. The queen will return to the hive while the drones gear continues to inseminate her. Workers will remove his kit and toss it away.

Queen bees are just regular larvae but they are fed a special royal jelly that causes them to mature into queens.

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