Recent comments in /f/askscience

PerpetuallyLurking t1_j5uv6pk wrote

Yeah, the fact that no one dies OF herpes has a lot to do with the impetus to find a vaccine vs everyone who gets rabies dies. And even then HPV is related to herpes, can lead to cancer, and now has a vaccine. So…wait patiently, probably. They’re working on the deadly ones first, not the annoying ones that do have a reasonably easy treatment.

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KnoWanUKnow2 t1_j5uutzb wrote

Only the pregnant female polar bears dens. Technically they don't hibernate, as their body temp does not fall and her heart rate does not drop. But she will stay in the den from around October until around May, not eating and not leaving, while she gives birth to her cubs and feeds them for the first few months.

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Rule_32 t1_j5ut7dr wrote

>sun loses mass leaving Earth beyond its grasp

This is incorrect. The Suns expansion does not equate to mass loss. Cosmologically its mass will have not decreased that much (which is what will determine where Earths orbit is) but it'll be fusing helium into carbon which is a hotter more energetic process and so the outer layers of the star will get pushed out and the star expands. Earths orbit won't change much however the Suns radius will expand to near or fully envelop Earth.

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MrWrock t1_j5usklc wrote

Temperature definitely changes but food source changes probably have more of an effect. Black bears on BC's Vancouver Island don't hibernate due to tear round food sources.

In fact, no bears truly hibernate. They wake up, stir around, stretch, and go out for food when the weather is nice. What they do is called torpor

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prohotpead t1_j5usiaa wrote

It's called having a healthy diet and exercising regularly. People who eat mainly a Mediterranean diet live longer than people with other less healthy diets. There is already a big difference in people who are unhealthy and uncomfortable in their own body by their 60s and people who regularly practice moderate exercise and eat healthy diets who can live comfortable adventurous lives into their 80s and 90s.

Sometimes the world is cruel and someone does everything the can to be healthy and fit into old age but they are robbed of that experience by tragic events and/or disease. Life's not fair.

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FellowConspirator t1_j5urcxn wrote

To make a vaccine, the thing that you are making a vaccine against (typically a virus) needs to have a prominent protein on it's surface. The vaccine can be inactive virus, or parts, it doesn't matter, you just need to provide the foreign protein to the immune system so that it can learn to recognize it so when a virus tries to infect, the body is prepared to stop it.

Viruses mutate over time, and if the protein on the outside tends to change a lot, it can be difficult to make a vaccine against. It turns out that small changes in the protein can really change the shape, and it's the shape that the immune system recognizes. The other thing that can make it tricky is that some viruses tend to carry a bubble of fat around them that hides the protein so the immune system can't see it.

HIV is difficult because it has another trick up it's sleeve: it attacks the immune system itself, meaning that if it gets a foothold, a vaccine would be useless because your immune system can't fight back. AIDS, the disease caused by HIV, happens with the immune system pretty much fails because the virus has disabled it. The person starts getting all sorts of infections and cancers that they wouldn't normally get, and that's what makes it deadly.

COVID-19 was simple, for a few reasons: we're already familiar with this type of virus (we've known about coronaviruses for over 60 years, how they work, the genes in them, etc.) and they have whopping big proteins on the surface that don't change a whole lot with time. We also know have molecular biology technology developed in the past few years that makes it possible to rapidly sequence RNA, synthesize RNA, and deliver RNA to cells to express it. So, it took about 3 days to sequence the virus, and a few weeks, to synthesize the RNA message that could teach cells to produce the surface protein of the virus and teach the immune system to recognize it. The whole process could technically be done in a week -- the parts that slow it down are: scaling up production, setting up quality control to make sure it's consistent without contamination, and all the safety testing and process to review safety data, get permission to proceed, etc.

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FelisCantabrigiensis t1_j5uq5rq wrote

I haven't kept up with the exact differences, but I will say that rabies is 100% deadly and herpes is 0% deadly, which may affect the amount of effort put into this.

Rabies also does not hide out in nerves. It travels along nerves to the brain, but it doesn't hide there in a mostly-inactive state for a long time. It vigorously infects nerves and travels along them, which makes it more vulnerable to immune cells and also triggers more response from immune cells.

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HighlandHiker t1_j5up3ja wrote

Quick add-on: Test specificity is how good it is at a positive result being a true positive result (not false positive). Sensitivity is the same for negative results (true negative, not false negative). A test with good specificity and/or sensitivity can be useful as a tool. Worse sensitivity and specificity make it less useful.

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Erlian t1_j5uodaz wrote

I find it hard to believe - as far as I know this viewpoint is not mainstream. Maybe cherry picked, but more likely the study isn't a very representative or large enough sample. It could also be that these policies in theory should help the labor side, but in practice there are some confounding variables - ex. "well we would pay you more except for this pesky law preventing us, sorry" being used as an excuse, or general disdain for the idea of raising everyone's wages vs. stagnating most employees' wages save a few favorite employees / new hires.

Could also be that a requirement to post salary ranges gives companies better information on what the lowest wage is that prospective employees would truly accept.

I also find it suspect that the article is lumping together a study that focused on pay transparency and university professors, with a different study on a pay disparity law and saying their results suggest similar conclusions. They are different policies, different samples, and different effects - tricky comparison to make.

Was having trouble finding other studies, but here's a good place to dig around: https://scholar.google.com/scholar?hl=en&as_sdt=0%2C38&q=effects+of+pay+transparency+on+wages&btnG=

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