The mass of a tree is composed of carbon fixed from CO2, so it doesn’t make any physical sense for a tree to grow at all without absorbing CO2. This is nonsense, trees begin fixing CO2 the moment they start growing.
The “cure” for rabies is to treat it with a vaccine prior to symptoms appearing. The rabbies vaccine is 100% effective and you will not become symptomatic if you treat soon after the bite. The Milwaukee protocol has been tried and it’s a last ditch effort for people who didn’t get the vaccine shortly after the bite and are now showing symptoms. They don’t even know if the Milwaukee Protocol is what prevented death or if the people it worked on were somehow resistant to rabies.
Because unless you’re living and working in a high risk environment, there’s no need for a human to go get a rabies vaccine because they can just avoid mammals that are acting strangely. It’s not like it’s airborne, you have to get a penetrating bite from a symptomatic animal to get it, so when that happens you just go to the doctor. You’d still likely get the vaccine even after a bite even if you had been previously vaccinated.
Vets and people who work in animal shelters often get the rabies vaccines beforehand. But even if you have been vaccinated previously, you still have to get it again if you are bitten.
The efficacy of vaccines usually declines over time after administration. The immune system starts to “forget” how to fight a pathogen it doesn’t encounter. It doesn’t completely forget, but it puts the treatment data way back in the archives. So when it encounters the real deal, it can take quite a while to boot up production of antibodies. It also varies by the type of disease.
This is fine for some slow diseases ( which is why sometimes a single vaccination can suffice ), but can be risky if the disease progresses faster than the immune system can ramp up the defenses.
Administering the vaccine as soon as possible after suspected exposure to deadly or highly contagious diseases simply helps the immune system to get the necessary blueprints to get in the fight quicker.
Administering the vaccine before any exposure at regular, long intervals is done to decrease the baseline risk. Sometimes you don’t know you have been infected. Many diseases are not only transmitted by dramatic, obvious vectors. In those cases, it’s definitely better to have some old defense than none at all.
In addition to what Senshi said, if you have recieved the full course of vaccines (4-5 doses spread over a month), any future bites need only 1-3 doses. Also the time within which you have to take the first dose increases from 24 hours to 2-3 days, which can be quite useful to vets in remote places.
I remember watching a video where they added some liquid visible with UV to the water and flushed, there were droplets everywhere including the tester’s face.
It’s not a study but it’s enough to make me close the lid, especially when my toothbrush is in the same room.
Yes, toothbrushes live uncomfortably close to the loo in my house too.
A friend gave me some light banter about closing the lid = under my wife's thumb but it's absolutely about me attempting to keep the toilet business contained to the toilet!
Someone once tried to argue against it by saying it still got the droplets in the air with the lid closed so there’s no point. My counterargument was that it still contained a lot of the droplets by closing it and that it’s the most minor of inconveniences to close it so you should just do it anyways.
This kind of thinking is just superstition. The earth magnetic field does NOT influence in any way your sleep.
This is just magical thinking distortion.
The bed must be only in a cozy and dark environment, not too warm nor too cold. Also, your bed room must be used only to sleep or sex. Don’t do any exciting or stressful activity on your bedroom.
Do you mean to say that sex isn’t exciting. Or are we only supposed to have boring sex in our bedrooms. Or are you implying that the only exciting sex happens outside the bedroom?
Sex is for procreation only. No fun or excitement allowed. It must be silent, and exclusively in the missionary position. Deviation from these rules is unacceptable.
That’s a strong claim you’ve got there. It seems humans do possess some amount of magnetoreception, there’s even a suggested mechanism. It might be jammed by certain radiofrequencies, although I don’t know if they are still in use. Some other mammals have been shown to sense magnetism too. Personally, when I’m in a bed, especially a new one, I feel my rotation relative to my normal bed. It isn’t very precise and it’s difficult to test, so I can’t be entirely sure, but that’s how it feels. I don’t know about any studies relating magnetism and sleep. I know there historically were people who claimed it matters to them, but I think that unless you already know that it matter to you, it probably doesn’t. I’d say that much more important is darkness. Also, I heard people feel better with feet towards the door, but I don’t know if it’s proven in any way.
I wonder why I’m being downvoted. I very much welcome discussion. If you want to tell me why I’m wrong, like that cryptochromes cannot be used in sensing magnetic field upon closer look etc., I’d be excited. Disagreement without pointing out any mistakes I did brings me nothing.
If it’s just disbelief, I would’ve preferred being asked for sources. Even wikipedia mentions some of what I wrote (en.m.wikipedia.org/wiki/Magnetoreception) and while I admit my source isn’t primary literature, it is a monography about senses and I would’ve made an effort to track down at least some of the original papers.
It’s toxic, but a useful reference point: tungsten hexafluoride is one of the densest known gases in existence. At a density of 13kg/m^3 at standard temperature and pressure, it is nearly two orders of magnitude shy of being dense enough to bring a human (~1000kg/m^3) to neutral buoyancy.
Compressing a gas to nearly 100x it’s natural density is going to dramatically increase it’s temperature. In simplified mechanics, you can basically think of it like all the energy that makes it the temperature it is naturally will still be there when it is 1% of it’s original size. So all that energy is “overlapping” and adding together to make it’s new temperature based on there being 100x as much energy in each place now. Even if it started at 10 degrees Kelvin, assuming a linear gain, it would be 1000 degrees Kelvin after compressing.
Of course all of that is super simplified and not the “real” math or mechanics in all their complexity. But it should help illustrate why it would not be possible or a good time.
And that is only the temperature half of it. Compressing an area to 100 atmospheres, which I’m presuming would be the level of pressure necessary to get that gas (or a safer slightly less dense one) to the needed density range, would also be pretty dangerous if not immediately fatal to the human. Again that level of pressure is assuming a linear gain, I don’t know for sure if it would be linear.
So even if you manage to find something you could breathe, you wouldn’t be able to at that level of pressure. You would need to be wearing a suit that can be pressurized and breathing from something that isn’t feeling that pressure. Which completely defeats the whole point of choosing a medium to be immersed in that doesn’t require a suit or tank like being in water does.
It is however, theoretically possible to breathe liquids. Just incredibly uncomfortable for humans. There are humans that have survived it in experiments. After an initial adjustment period where your brain is certain you are drowning for a few minutes, eventually you are able to over ride that when you don’t die. Then you can hang out for a bit not dying despite it seeming like you should be… and then when you are done breathing liquid, the terrible part starts, you have to get the remaining liquid out of your lungs so there is room to put air in them again. As much as the rest is not great, transitioning back to air was universally considered the worst part of the experiment.
You’re talking about adiabatic heating, which is where temperature changes due to change in pressure, without heat transfer. If we thermally isolate the gas as we compress it, the temperature will rise.
We don’t have to insulate it. We can allow the heat to transfer out of the gas as we compress it. Heatsinks on the pressure vessel will pass the heat from the pressurized gas into the ambient air until their temperatures equalize.
Since we can add or remove heat from the gas after it is compressed, the temperature of that gas is only relevant if it falls below the boiling or freezing curves, allowing the gas to condense into a liquid or solid.
You could likely fly using human power on Titan. It has a 50% denser atmosphere than earth as well as only 14% of the gravity. While that’s not neutrally buoyant, it is enough that if you had some big wings attached to your arms you could generate enough lift to fly by flapping. Comic by XKCD about this topic.
Of course, Titan is also insanely cold, so you’d need a pressure suit, which might throw off the calculation.
This also reminds me of a scene in Arthur C Clarke’s 3001: The Final Odyssey, a relatively less well known sequel to 2001. In this scene there are enormous space elevator towers that house humanity, and in the upper floors where there is low gravity they have a pressurized flight room just for the fun of it.
We have pressurized areas in microgravity today (space stations), which would obviously give you neutral buoyancy. Not a whole lot of room to maneuver around though!
Capitalism. Anything that isn’t bought fresh in the US is LOADED with sugar because food manufacturers figured out that sugar is extremely addictive, and they also buy a lot of politicians so that nothing can be done about it.
Don’t forget corn subsidies that make corn syrup and corn products artificially dirt cheap. Other crops get subsidies as well but you better believe fresh fruit and veg aren’t on that list. It’s the same reason meat is so cheap in the US.
Something else that I have noticed, that I believe is related to capitalism as well, is the portion size at restaurants and take out. They have conditioned us to think that a 1200 calorie meal is a normal size and if it’s smaller we are not getting a good deal. Cheesecake for example sells the skinnylicious meals that are about 550 calories, which I consider a normal dinner size, as if it’s diet food. It’s almost impossible to eat out and stay within a reasonable calorie range.
Seriously this. I lived in the US for most of my life until 2020 when I moved to Norway. If Americans paid what we pay here for the portion sizes given, they would absolutely riot. It’s so expensive to eat out here and the portion sizes are like, a third of what you’d get in any US restaurant. And that’s okay because…
I lost like 60lbs the first year we were here by simply eating a sensible portion size and not having a shitload of ready to eat mindless consumption snacks in the house. (also walked everywhere. Everywhere.)
Now I can tell who is a tourist just by size alone like 80% of the time (I live in a very touristy city). Brand new sneakers and look to be over 300lbs? Almost always walk by me speaking American English. It’s honestly quite surprising to see a very obese person here and then hear them speaking fluent Norwegian.
Sugar is only part of it. Corn and wheat based products are just as bad.
The truth has to do with food availability as well, not just what it’s made of.
Food availability has increased in the US over the past 50+ years, to where we have over 4000 calories per person a day now. Easy access to unhealthy food is a major contributor to our obesity. People don’t even understand what a healthy diet looks like and have a very poor grasp on how much to eat. We just eat until we’re stuffed and then wonder why we’re fat.
It’s especially tough as people age. I’ve been tracking my diet for 180+ days, eating under 1800 calories a day, and I still struggle with losing weight. Without a lot of effort towards eating the right amount and the right foods, people get fat.
A better question would be, “when does hair know when to fall off?”
Hair never stops growing.
Edit: when I say “hair,” I mean one single strand of hair. That single strand of hair will eventually fall off. The thing is that not all strands fall off at the same time. So hair, the full head of hair, seems to be of the same length (especially if we keep getting haircuts.) But it’s not like all hairs grow and then all of them collectively say “ok, everyone, let’s stop growing!” and stop. No, each single strand of hair falls off, but at different times.
What’s „unhelpfully pedantic“ about a correct answer that explains OPs misconception? 🤡
The person above said hair doesn’t stop growing. That’s wrong. It does. It grows, then it stops growing, then the dead hair falls out. Why does it know when to fall out? Because it’s dead, Jim.
OPs question was why the hair on their head grows longer. Answer: because it’s growing cycles are longer.
I’d say you’re unhelpfully pedantic telling other people giving helpful and correct explanations they’re „unhelpfully pedantic“.
I’d say you’re extremely unhelpful because you give an „explanation“ that’s just complete bullshit and doesn’t explain anything.
Metal ions can perform interesting chemical reactions that organic molecules cannot. A positively charge metal ion can also naturally bind to negatively charged proteins. So the organisms that more successfully took advantage of these chemical reactions reproduced more effectively than the organisms that didn’t.
Ignaz Semmelweis tried to convince the medical establishment that washing hand stop’the spread of disease in hospitals. His colleagues responded that doctors are gentlemen and gentlempdo not have dirty hands. Semmelweis was committed to a mental institution soon after and died from an infection as a result of a beoti’he received from institution workers. A few decades later the four humors school of medicine was replaced with diseases caused by microorganisms.
Imagine living at a time when the germ theory of disease wasn’t widely accepted. You might even need to convince people that microbes exist. If they already know about microbes, they might believe that microbes spawn out of thin air through abiogenesis. Previously that word was used when talking about microbes spoiling food whereas nowadays it’s applied to the early stages of the earth.
Many herbivores have a part of the digestive tract devoted to fermentation (or other microbe based processes) to break down cellulose. This involves a community of microorganisms that live in that part of the gut, and it is those microorganisms that break down the plant matter, producing nutrition for the animal via the products of their digestion, or by the animal breaking down the microorganisms themselves. Ruminants in particular like cows with their specialized multi-compartment stomach devote a lot of space to culturing this microbe colony, but rabbits and horses are hind gut fermenters so they have cecum for that. Rabbits also are coprophagic (eat poop), they digest some of their plant matter once, then eat the poop pellet and send it through again so it can be broken down even more.
But basically, with the microbes doing the work of digestion, it is more about what they can extract, and the herbivores just host them. We have a different community of microorganisms than them, and our digestive tract wouldn’t be able to support large numbers of those species.
Fair criticism, and in regards to minerals especially, I totally failed to mention the need for herbivores to have access to literal rocks and dirt rich in different minerals that aren’t readily available in plant. In captivity, this takes the form of mineral blocks of course.
The fact they spin and the bits interact gravitationally makes them symmetric. There are almost certainly some asymmetric galaxies as we know galaxies collide and they will be asymmetric for a bit afterwards, but the spinning and fiction of gravity will make them symmetric again fairly quickly on galactic time scales.
Not exactly a scientific debate, but among the general public there was strong opposition to the idea that rocket engines would work in space, where there’s “nothing to push against.” Famously, the New York Times editorial board mocked Robert Goddard (the rocket scientist that now has a NASA space flight center named after him) in a 1920 article:
“That Professor Goddard, with his ‘chair’ in Clark College and the countenancing of the Smithsonian Institution, does not know the relation of action to reaction, and of the need to have something better than a vacuum against which to react — to say that would be absurd. Of course he only seems to lack the knowledge ladled out daily in high schools.”
The New York Times eventually formally retracted that op ed, on July 17th, 1969 - while the Apollo 11 crew was already en route to the moon. The retraction is pretty funny:
Further investigation and experimentation have confirmed the findings of Isaac Newton in the 17th century and it is now definitely established that a rocket can function in a vacuum as well as in an atmosphere. The Times regrets the error.
Goddard wasn't just another rocket scientist, he was the inventor of the liquid fuel rocket! And he also made a ton of other key discoveries about rocket design that formed the groundwork for rocketry as we know it today.
The Milwaukee Protocol is a treatment plan that is essentially a more advanced version of what you’re asking. The patient is put in a medically induced coma and then given antivirals and IV fluids, which avoids the issue of hydrophobia.
and didnt they use it on that girl that survived cause she didnt report the bite until it was too late, so it was either try something dangerously crazy like Mulwaukee Protocol, or just die miserably?
I guess whether this protocol should be abandoned, rather than iterated on to improve its chances of success, to me, depends on the effect the coma has on the patient's quality of life while the protocol is attempted. It's arguably more humane to put someone in a medically induced coma while they're still sane. If the protocol fails, the patient is at least not conscious while their brain is deteriorating.
Standard gravity is 9.80665 m/s2. That the number defined by the metric people who set all the world’s units. In schools in the united states of america, we used 9.8. I don’t recal using any more precision than that. Gravity at the surface does vary, but you don’t need more presision than that for most academic purposes.
Is that so? I wonder what the story behind that is. Maybe it’s a surface average?
Most people would probably guess this, but meters and seconds are defined independently of Earth’s gravity, so it doesn’t have a true value, just apparently a standard nominal one.
Standard gravity was adopted as a standard in 1901. That was at the 3rd meeting of the General Conference on Weights and Measures. They redefined a litre as 1 kilogram of water, but the volume of water depends on the pressure, and the pressure depends on the local gravity, so they had to come up with standard values for both standard atmosphere and standard gravity. You also need a standard value for gravity to define a standard for weight measurements which was also done.
Standard gravity is the acceleration at sea level at 45 degrees latitude. The official number was based on measurements made by Gilbert Étienne Defforges in 1888. I can’t find details about his methodology without going to a library or something, and that’s not worth the effort for an internet comment.
No, it’s not worth it. Honestly that’s great all on it’s own. I guess they never had a reason to update it, then, since anybody that needs a more accurate value would just measure it themselves.
It looks like they went back to the original litre definition a few decades later. I’m not sure why they thought defining volume by mass rather than geometry was better in 1901, anyway. Some fun facts about the kilogram itself, since I never get to talk about this stuff:
Since 2019 the kilogram has been based on a “Kibble balance”, which is a contraption that precisely measures the force produced by electromagnetism. The necessary electricity is provided by circuit with a material that has quantised resistance near absolute zero, and a superconducting junction which produces oscillation exactly tied to the current flowing through, which is itself timed by atomic clock. This allows you to measure it out using just the new fixed value of Plank’s constant.
Before 2019 there was just a chunk of metal the was the kilogram, which is hilariously low-tech.
I think when people say it’s only predicting the next word, it’s a bit of an oversimplification to explain that the AI is not actually intelligent. It’s more or less stringing words together in a way that seems plausible.
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