Wikipedia:Reference desk/Archives/Science/2019 March 23

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March 23

Solar system

A solar Photovoltaic system on a rooftop in Hong Kong

What is solar system — Preceding unsigned comment added by Asad Emar khan (talk • contribs) 12:42, 23 March 2019 (UTC)

See Solar system. ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:47, 23 March 2019 (UTC)

The solar system is as Bugs describes: a solar system is any star surrounded by orbiting planets, both not to be confused with this:

Basil as a channel modulator

Basil is listed among TRP channel modulators. If so, is it safe to eat it moderately? Thanks. 212.180.235.46 (talk) 14:18, 23 March 2019 (UTC)

No. 2A02:C7F:A05:DC00:D08E:5CDE:4794:DABC (talk) 14:21, 23 March 2019 (UTC)

Then why am I able to buy tomato soup flavoured with basil (in the form of visible leaf shreds) in most supermarkets, as well as jars of it from amongst their range of spices? The Wikipedia article linked by the OP describes many culinary uses: I suppose "eat it moderately" is open to interpretation – perhaps the OP can clarify what they have in mind. {The poster formerly known as 87.81.230.195} 90.200.138.194 (talk) 05:02, 24 March 2019 (UTC)

The chemical component found in basil that explains its presence in the above template is eugenol (the concentrations depend on variety and location grown [1], [2] - some types have almost none). Our eugenol article has some information on the toxicity of the pure substance. Mikenorton (talk) 12:18, 24 March 2019 (UTC)

• Note that TRPA and TRPV are receptors associated with sensation of mechanical stress and temperature, so you would expect that their level of activation could be changed (within reason) without much ill effect. (Pepper aficionados would admit there is a limit to that) If you look at the infobox you'll see that the effects of TRPC and the drugs that modulate it both sound more serious -- but that is a different protein, related only by homology. Wnt (talk) 14:18, 24 March 2019 (UTC)

Having eyes like a rabbit.

Where humans have ears, is where rabbits have eyes. If you see the photos directing looking at the front of a rabbit, you can barely see their eyes. So it seems rabbit can barely see directly in front of them, they always have to turn their head. Certain birds like flamingos or so are like this. Is there a word for this phenomenom? Humans have binocular vision, which is where our eyes focus as 1, I think it'd be pretty hard to have our 2 eye look directly in front and separate of each other, thus seeing 2 visions at once. But I am curious, Wikipedia have articles on cat intelligence but not rabbit intelligence, does having 2 eyes on opposite sides of the head can confuse the rabbit? Is it like seeing 2 T.V. screens at once. Must be pretty tough to be born like that and having to figure out how to work the visions with motion. 67.175.224.138 (talk) 15:21, 23 March 2019 (UTC).

The first part of your question is discussed in Binocular vision#Field of view and eye movements. As for the last part, you're approaching it from the wrong way. For animals with vision like that, it's how their whole visual system including brain has evolved, and it's all they know. Nil Einne (talk) 16:45, 23 March 2019 (UTC)

Comparing with humans, our eyes have much more overlap, but there is still some portion we can only see with the right eye or left eye, yet our brains are able to put it all together into a single picture. Same with rabbits, just with less overlap, and therefore less ability to judge distance stereoscopicly. They may rely more on other distance cues, like relative sizes of objects, the focal distance required for a sharp image, etc. Also, there can be a dynamic stereoscopic effect where they move their head (and maybe body as well) comparing the two images. I've used this technique before, when unable to tell if I am seeing a large distance object or one closer and smaller. (If the object doesn't seem to move when I do, then it's large and distant.)

Also note that in general predators have forward facing eyes, for better tracking of prey, while their prey animals have widely set eyes, better to watch for predator's sneaking up on them. An interesting question is why evolution never provided larger animals with more than 2 eyes, such as spiders have, as this would seem to provide better vision to the sides (and maybe back) without sacrificing any depth perception. Presumably the negatives (increased routes of infection, more brainpower needed to stitch it all together, more moisture loss) must outweigh the positives. Or perhaps there just isn't a clear evolutionary path there, as 2.1 eyes are less useful than 2, not more.

You might also be interested in the chameleon vision, since, as both predators and prey, they evolved a complex visual system to deal with both situations. SinisterLefty (talk) 19:27, 23 March 2019 (UTC)

The problem isn't whether a fraction of an eye would be useful (it probably would be), but where the other eyes come from. Evolutionary change is constrained by what it has to work with. No matter how "useful" something would be, it won't develop from nothing. Body parts and body processes that already exist get co-opted for other uses and develop to fulfill those uses better. Think of the "panda's thumb". A real thumb would have been more useful for the panda, but that digit was already modified for something else. Random variation in the wrist bones led some ancestral pandas to have a larger radial sesamoid that was then adapted for use as a makeshift thumb.--Khajidha (talk) 21:44, 23 March 2019 (UTC)

Assuming that it's pertinent, the pineal gland is kind of a heavily derived third eye and is still functional in some vertebrates. Jo-Jo Eumerus (talk, contributions) 22:14, 23 March 2019 (UTC)

Okay, now I don't suspect we know what it's like to have the rabbit visions. Suppose we looked at 2 microscopes, 1 for the left eye and 1 for the right eye at the same time. And each microscope was like to a dark movie theater with a different screen image. We would most likely not see them as images next to each other, right, but kind of both images overlapped at the same time? Which I think would feel initially dizzy with. I'm guessing when a rabbit sees predator coming on 1 side, they must have some ability to pay attention to 1 eye more than the other? 67.175.224.138 (talk) 07:37, 24 March 2019 (UTC).

Yes, that must be the case, the rabbits brain synthesises both images into a single picture, but the pertinent detail comes from whichever eye can see the point of interest. For humans who can use both eyes for a single object, we have ocular dominance so that most of us are really seeing with one eye only, the non-dominant eye just provides back-up information. Alansplodge (talk) 10:36, 24 March 2019 (UTC)

I'm pretty sure you can see dimmer stars without an eyepatch than with. At least if your eyes are similar enough quality. It probably needs at least a few seconds of arc parallax before the brain throws out the binocular part of the non-dominant eye feed. Sagittarian Milky Way (talk) 15:53, 24 March 2019 (UTC)

Which is apparently called binocular summation (though brighter images is not the only kind) Sagittarian Milky Way (talk) 00:04, 25 March 2019 (UTC)

It's possible that they simply have one combined visual field. But without looking at the research, I wouldn't be sure. Intrinsically it also seems possible that the way their brain works is it's much closer to simply having 2 visual fields. As I said above, while it may be difficult for the OP to imagine how this will work, if that's how they evolved, it's simply how things work for them. Nil Einne (talk) 04:00, 27 March 2019 (UTC)

Note that humans also have the ability to only pay attention to one item at a time, say if one object is moving in an otherwise still field. So, it's not surprising that other animals would share this ability, especially since it's quite vital for survival. SinisterLefty (talk) 18:39, 25 March 2019 (UTC)

This is actually a very old natural determination. Rabbids and many other "prey" have their eyes on the side to manage a nearly 360° sight that prevent most sneaking up attempts of Predators. The Predators have their eyes in the front because that "stereoscopic way" helps to aim and measure distances very exact. --Kharon (talk) 23:46, 25 March 2019 (UTC)

Btw. with a VR-Headset and a VR-Camera it should not be a problem to implement your rabbit-view for just around 1000 $ in realtime. --Kharon (talk) 23:58, 25 March 2019 (UTC)

I've often thought that the reason predators look attractive is because they "look like us", i.e. they have binocular vision as we do. Going back to the OP's premise, if a rodent could talk, they might very well ask us, "How do you manage to survive when you can only see 50 percent of your environment at a given moment?" ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:52, 27 March 2019 (UTC)

Chondroplasty

Only one bibliographical reference from 1938 (!) is given there ... Is this still state of the art? (By the way, I came across that lemma while seeking a proper article to link to for the term "laser septochondroplasty" linked here. With regard to the latter issue, does anybody have an idea how to proceed (e. g. change the wording, or link only the words "laser" and "chondroplasty"?))--Hildeoc (talk) 17:29, 23 March 2019 (UTC)

Considering that the ref is to a medical dictionary, and word definitions don't change all that frequently, a 1938 entry may well still apply. More recent refs describing actual techniques would be beneficial, however. SinisterLefty (talk) 19:32, 23 March 2019 (UTC)

The word chondroplasty is cited in medical dictionaries from 2003, 2007, 2009 and 2012. Here is an abstract of an article about laser-assisted chondoplasty. DroneB (talk) 20:40, 23 March 2019 (UTC)

See wikt:chondroplasty. The word is literally cartilage + shaping, so any technical change shouldn't require a new general term. Obviously the article needs much expansion with links like DroneB's to avoid being just a dictionary definition. Wnt (talk) 00:29, 24 March 2019 (UTC)

agree w/ Wnt--Ozzie10aaaa (talk) 11:47, 26 March 2019 (UTC)