Recent comments in /f/askscience

Bax_Cadarn t1_jatgzop wrote

Reply to If cancer is caused by mutations in genes that regulate normal cell development/division, how does killing cancer cells prevent it from coming back? by [deleted]

You seem to misunderstand what a mutation means. A mutation is a random change in a gene. That happens millions of times in millions of cells in our body. Many of those mutations cause the cell to die, some don't change anything, some may make it get better at something, like not dying - putting it on the path to cancer.

If cell#74729194 mutates and becomes cancerous, it divides, divides and divides. If chemo poisons it and all its descendants, You should be cancer-free.

In reality, the more a cell's DNA is altered, the less stable it becomes, which makes every next generation of cancer different from the previous ones. That in turn makes it so all the cells are different, which can cause say 70% of the cells to respond to chemo while the rest won't.

The other problem You touched upon is what is considered a remission - yes, if we don't find a trace of it, we will consider it a remission - but we can't deconstruct a human to check every cell if there aren't 3 metastatic ones in that person's brain, one in the little left toe, and some next to where the tumor was. Best we can do is find a new small tumor, or some activity suggesting a metastasis, which can look similar to say an infection (and inflammation).

It is complicated, I think the first 2 paragraphs show what You wanted, and the rest is more corrections. Hopefully they are clear.

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Kaipakta t1_jatf1se wrote

Reply to comment by PlaidBastard in Mercury has a very elliptical orbit, but does it influence its temperature? by legendsplayminecraft

Yes!

To say, the difference in temperature relative to different points on its elliptical orbit on the side facing the sun range from: instantly overcook your pizza to... instantly overcook your pizza.

That being said- much like the nuclear explosion description, there is a spot on mercury's penumbra where the temperature is *perfect* for baking.

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Dominik_1102 t1_jatc19j wrote

Reply to What exactly does Spaghettification mean? by mark0136

imagine the front of ur car accelerates stronger than the back. eg. at some point the front is already moving whit 100mph ur back is still only moving 5mph. 1sec later ur front has accelerated to 200 while the back only got to 10mph.

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Dyanpanda t1_jatbngr wrote

Reply to Does being sick impair the body’s ability to form memories during that time? by Temporary_turbulance

The way memory works in the brain is heavily state dependent. That means that your recall and recognition of past ideas/events is based on how you feel, what you are wearing, mental state, drunkenness, drugged/not, sleepiness, and pretty much any other state of being you can think of. The closer you are to the state that you were when you learned or experienced something, the easier it will be to recall.

This doesn't un-do the depreciation in memory you get from drinking, or anything else. Getting black out drunk wont help you get your blackout memories back, you'll just forget what you were trying to do.

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Hot_Flan1220 t1_jatbncl wrote

Reply to What exactly does Spaghettification mean? by mark0136

Wouldn't it be like a Roche limit for non-gravitational structures?

With a biological structure orbiting a black hole, eventually the part closest will be moving so fast that it'll be ripped away/apart at the macro level, then cellular, then molecular, etc etc until total annihilation.

Like pressing a finger against the ultimate rotary sander.

(Uneducated but curious, so my terminology is probably inaccurate, please be gentle.)

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mschuster91 t1_jat12ky wrote

Reply to comment by heresacorrection in Does being sick impair the body’s ability to form memories during that time? by Temporary_turbulance

Covid has been linked to severe memory degradation (https://www.ox.ac.uk/news/2022-01-19-attention-and-memory-deficits-persist-months-after-recovery-mild-covid).

Anecdata: was out sick for two weeks, can barely remember anything from that time. Friend was out sick for months and struggled with massive memory issues for even longer.

We barely have an idea how viral infections affect the human body, and we're only now after covid beginning to take the significant toll that post-viral infections can have seriously. The ME/CFS / EBV link goes into a similar direction and I would not be surprised if recent research linking Alzheimer, Parkinson and ALS to viral infections (https://www.science.org/content/article/study-links-viral-infections-alzheimer-s-parkinson-s-many-caveats) gets onto a more significant foundation as well.

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babar90 t1_jaswwin wrote

Reply to Mercury has a very elliptical orbit, but does it influence its temperature? by legendsplayminecraft

Obliquity is very low. The irradiance is proportional to the squared distance, that means that the irradiance oscillates between x and 0.43 x depending on the season.

This is roughly equivalent to the seasonal irradiance oscillation that you'll have on earth at 45° latitude north.

But as PlaidBastard said this computation is meaningless, as the very slow rotation on Mercury makes the day vs night dominate the seasons.

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