Recent comments in /f/askscience

Patsastus t1_j946f5s wrote

Reply to comment by Reliv3 in Was reading something related to Rock Salt mining. In places like the Himalayas where rock salt mining is done in cold temperatures, a lot of miners report burns. Why is it so that salt burns in a colder surroundings? Would it be the same reason why the salt ice challenge was so dangerous? by vvdmoneymuttornot

It's more that "molten" is an extra descriptor used for the liquid state of something that's usually solid. So molten ice sounds fine, molten water sounds weird and tautological, because of the assumption that you mean liquid water the majority of the time you say "water"

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seanbrockest t1_j945b43 wrote

Reply to comment by PyroDesu in Was reading something related to Rock Salt mining. In places like the Himalayas where rock salt mining is done in cold temperatures, a lot of miners report burns. Why is it so that salt burns in a colder surroundings? Would it be the same reason why the salt ice challenge was so dangerous? by vvdmoneymuttornot

Mostly true, but there are wet mines. My company used to have one on the East Coast of Canada that literally went out underneath the Atlantic Ocean. They were under the ocean!

The rock was very cool, so all humidity coming in on the fresh air formed as condensation on the walls, creating a wet mine.

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PyroDesu t1_j943lbx wrote

Reply to comment by seanbrockest in Was reading something related to Rock Salt mining. In places like the Himalayas where rock salt mining is done in cold temperatures, a lot of miners report burns. Why is it so that salt burns in a colder surroundings? Would it be the same reason why the salt ice challenge was so dangerous? by vvdmoneymuttornot

Most salt mines are dry, because salt is hygroscopic.

Apparently it makes ones which are no longer actively being mined very useful for preserving things like film, books, etc.

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aphasic t1_j943j0f wrote

Reply to comment by Interesting-Month-56 in Why are fevers cyclical? by Key-Marionberry-9854

It's also worth mentioning that the human immune system is an insane rube goldberg machine where almost every pathway has multiple mechanisms of negative feedback regulation. It's almost universal that when your cells sense a cytokine produced by a viral infection, like interferon gamma, they respond to it (inflammation, fever, antiviral gene transcription, etc), but they also up-regulate genes that serve to dampen the cell's response to interferon. If you put a cell in a steady state amount of cytokine, it will usually have a strong initial response, followed by a damping of the signal. There are a lot of mechanisms by which this happens (down-regulating the receptor, up-regulating the inhibitors of the receptor, etc.)

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Gradus83 t1_j943ikk wrote

Reply to Are the flu strains we vaccinate against more or less the same world-wide? by heyheyhey27

Recommendations for vaccines are made globally for each flu season, but it’s important to note that there are actually two “flu seasons” in a year, the northern hemisphere and the southern (corresponding to winter in each). The recommendations are made every 6 months, so other parts of the world may have a different vaccine in the same calendar year.

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WAGUSTIN t1_j942f2t wrote

Reply to Why are fevers cyclical? by Key-Marionberry-9854

In many instances, pathogens display antigenic variation. Your immune system makes antibodies in response to pathogenic antigens, but some pathogens display a survival technique wherein they swap out their antigens so that the antibodies your body just made don’t work anymore. Sometimes this is a built-in mechanism, such as in relapsing fever. The pathogens in this instance are some species of Borrelia, where it can rearrange its DNA to dodge your immune system. Plasmodium, the family of protozoa responsible for malaria, also displays this strategy, and also has a characteristic presentation of cycling fever (which is two or three days depending on the specific species). In other cases it can simply be random mutations that result in cycles of fever due to selective pressure, wherein your immune system kills off pathogens with one antigen, leaving the pathogens with other antigens to proliferate. The Hepatitis C virus is good example, which even has an RNA polymerase that can't proofread gene copies, effectively encouraging mutations. Your body therefore goes through periods where it makes antibodies against a certain antigen (which can take a few days), kills off pathogens with that antigen, leading to reduced symptoms, but then leaves a few that switched antigens. The survivors proliferate and force your immune system to have to make different antibodies, repeating the process.

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seanbrockest t1_j940qb8 wrote

Reply to Was reading something related to Rock Salt mining. In places like the Himalayas where rock salt mining is done in cold temperatures, a lot of miners report burns. Why is it so that salt burns in a colder surroundings? Would it be the same reason why the salt ice challenge was so dangerous? by vvdmoneymuttornot

Canadian Potash (potassium chloride instead of sodium chloride) mine here. Our mine is roughly 76% NaCl and 22% KCl. What we mine is then refined. Our mine is dry, so I've never experienced salt burns, but if you have other questions I'd be happy to answer them.

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LivingDegree t1_j93yrje wrote

Reply to If a human being is bleeding internally say in their mouth or stomach would they still have a risk of anemia? by Robbeee

Yes! This is actually how you can pick up on chronic internal bleeding within the digestive tract (along with constitutional systems like black tarry stools/dark stools); it’s called anemia of chronic disease. You see this occur in your inflammatory bowel diseases. On routine labs you can see an anemia and it clues you into a long term inflammatory process if you can rule out diet deficiency or other hematological pathologies.

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