Recent comments in /f/askscience

EarthSolar t1_jbz5gqh wrote

Reply to Is the percentage of mass in the parent star, comparable between different systems? by bizzehdee

We do not have data for the lower end, but we do have some clue of where the higher end may be. We already have discovered a few systems where the mass fraction is very different from the Solar System’s (where planets take up ~0.134% of all system mass). Going by Wiki numbers, Gliese 876’s mass fraction within known planets is almost 1%, while Titawin and HR 8799 both have that number at almost 2%.

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ChromaticDragon t1_jbz47a9 wrote

Reply to comment by Oheligud in As they still have a neutral charge, can antineutrons replace neutrons in a regular atom? by Oheligud

To give you some meat to chew on regarding the descriptions others have already provided you, check out this paper, specifically section 5.5:

>Annihilation on neutrons
>Antiproton–neutron or antineutron–proton interactions at rest offer additional opportunities to study annihilation dynamics.

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Darryl_Lict t1_jbz3nva wrote

Reply to comment by KahlessAndMolor in There are certain species of mushrooms that can't be cultivated artificially and only found naturally in the wild, are there also any plants that are unable to be grown artificially? by PianoTrumpetMax

I assumed that wasabi would get a mention. I think I've had real wasabi at a fancy schmancy sushi restaurant, but I'm perfectly OK with green dyed horseradish because that's what I was weaned on. In the past few years, farmers have developed agricultural practices to successfully grow wasabi. The one I remember specifically was using greenhouses and water sprayers and not growing in an environment specifically mimicking the free flowing fresh water streams where wasabi grows in the wild.

https://s3.wp.wsu.edu/uploads/sites/2709/2021/06/PNW605.pdf

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danby t1_jbz36wk wrote

Reply to comment by slashdave in What exactly is going on when a protein (or other molecule) binds with a receptor? by Eat-A-Torus

> The intermediate states are irrelevant

Irrelevant to what? They seem pretty relevant if we're studying protein dynamics.

> It is only the free-energy difference of the two states (bound and unbound) that matter.

It's the only information that matters to what? If we're studying protein dynamics can you predict if a protein undergoes a change in structure form the change in free energy alone?

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off_the_cuff_mandate t1_jbz3296 wrote

Reply to comment by KahlessAndMolor in There are certain species of mushrooms that can't be cultivated artificially and only found naturally in the wild, are there also any plants that are unable to be grown artificially? by PianoTrumpetMax

Real wasabi looses its flavor in about a half hour after being prepared and intact rhizomes must be stored very carefully and even then will only last a few months. Which means wasabi can't be shipped.

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danby t1_jbz2kzo wrote

Reply to comment by slashdave in What exactly is going on when a protein (or other molecule) binds with a receptor? by Eat-A-Torus

Why on earth would we be only interested in simple cases?

MD is fine in many cases (very, very good in some) but it is absolutely not sufficient to fully model and understand the dynamics of proteins. We know the forcefields we have are lossy and not great for many applications when it comes to proteins. Simulations of long time spans or large protein rearrangements are generally very poor.

> You could say we are limited with what kind of computing power we can apply in complex systems.

Well yeah we limited there.

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robot_egg t1_jbyywyg wrote

Reply to comment by loci_existentiae in How do the physical properties of the isotope Iron-54 differ from the more common Iron-56? by Colonel__Kernel

I'm an organic chemist, not a metallurgist. I believe that conductivity and magnetism would be the same, but it's a little outside my wheelhouse.

You're not going to find pure Fe-54 or -56 in nature. They'll be mixed in more or less the natural abundance ratio anywhere you find iron. It's certainly possible to separate them; much easier than enriching uranium.

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KahlessAndMolor t1_jbyweza wrote

Reply to There are certain species of mushrooms that can't be cultivated artificially and only found naturally in the wild, are there also any plants that are unable to be grown artificially? by PianoTrumpetMax

Not an exact analog, but "real" wasabi is exceptionally difficult to grow because it needs a stream with moving water, and a specific set of nutrients in the soil near the stream, and it is tough to fertilize them because the water needs to be moving. And if you don't get the nutrients right, the roots are too small/craggy to use, because you have to cut off so much of the skin of the root, so it needs to be fat to use. So most wasabi paste you buy in the store is regular horseradish with some added color and flavor.

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Also, in the animal kingdom, it is considered generally impossible to milk a pig, even though they do produce a significant amount of milk. You can buy cow milk, goat milk, even llama milk, but not pig milk. The basic reason is that mama pigs are very aggressive and large animals and nobody has been able to develop a process to consistently get them to cooperate enough.

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