Wikipedia:Reference desk/Archives/Science/2022 September 1

= September 1 =

Inorganic chemistry: crystal field theory and ligand field theory.
Crystal field theory came 1st. Is CFT something that explains a good 40% of something, and the ligand field theory explains another 55%? Is there something that CFT explains that LFT does not? And then, is there a 3rd theory that continues from the 2, or were the 2 considered complete?

There is also, charge-transfer band, at 2 types: ligand-to-metal (LMCT) and metal-to-ligand (MLCT). This is very independent of the above 2, right, as the above 2 were for metal-metal only? D metals. Thanks. 67.165.185.178 (talk) 02:49, 1 September 2022 (UTC).

Pharmacology and foods.
The body has about 4 receptors and 7 neurotransmitters. Are there any drugs that reacts with all 4 receptors and all 7 neurotransmitters? Somewhere out there, there should be data on what the average drug does, like maybe the average drugs only reacts with 2 receptors and 3 neurotransmitters. Can there be drugs that react with receptors, but with 0 transmitters, or react with transmitters, but 0 receptors? Would water be something that reacts with 0 and 0?
 * Well, I've heard that humans have 40 neurotransmitters in use in the nervous system, and that the immune system has those 40 plus 1. And the number of receptors is huge, perhaps 1000? All cells are capable of expressing anything any other cell can do, even though some are specialized to produce more. I've also heard that every cell in the body expresses every gene, even long-dead pseudogenes, at least once per day, presumably by accident.  Abductive  (reasoning) 05:09, 1 September 2022 (UTC)
 * There are already five major groups of receptor molecules (ionotropic receptors, G protein-coupled receptors, tyrosine kinase receptors, enzyme-linked receptors, nuclear receptors), which have many members. From our article Neurotransmitter: "The exact number of unique neurotransmitters in humans is unknown, but more than 100 have been identified." --Lambiam 08:35, 1 September 2022 (UTC)

Also for a food question. Can there be foods A and B, A is healthier than B at low amounts, but not at higher amounts. Sounds like to the extent the answer is yes, is to the extent the food is not 100% food. 67.165.185.178 (talk) 02:53, 1 September 2022 (UTC).
 * Many a vitamin is needed for survival at low concentrations and will kill you at higher concentrations. Abductive  (reasoning) 05:09, 1 September 2022 (UTC)


 * Even drinking too much water (Water intoxication) can be fatal. 2603:6081:1C00:1187:A5DC:BD71:B7B:5DB6 (talk) 06:15, 1 September 2022 (UTC)
 * The healthiness of a food can only be considered in the context of a person's typical diet. For someone who usually only consumes meat and potatoes, Brussels sprouts are very healthy, but for someone who only munches cabbage, an extra serving of Brussels sprouts will hardly be an improvement. --Lambiam 08:00, 1 September 2022 (UTC)
 * The dose makes the poison - Paracelsus. -- Jayron 32 10:44, 1 September 2022 (UTC)
 * You know what for my own question I'ma go with spinach and lettuce. Small amounts of spinach should objectively be healthier than a filler-food like lettuce. But too much spinach can lead to too much iron, nothing much with too much lettuce. 67.165.185.178 (talk) 03:41, 5 September 2022 (UTC).
 * The idea that spinach is a good dietary source of iron is basically a myth. Spinach has a moderate amount of iron, but very little of the iron is absorbed by the body when it eaten. CodeTalker (talk) 07:18, 6 September 2022 (UTC)
 * Something of an accumulation of myths according Iron in Spinach from McGill University. It seems that Popeye never claimed that it is a good source of iron, and the false suposition that it is, didn't come from a decimal point error, as is widely believed. Alansplodge (talk) 10:28, 6 September 2022 (UTC)

Should COVID-19 survivors be careful or better not?
I heard someone on the radio claim that people recently recovered of COVID-19 are better off not being careful. The argument was that they have high immunity and therefore do not get sick from contact with an infected person, but then their immunity gets a boost. I don't know if the speaker was a doctor. Is this a known theory? A doctor at the hospital said she didn't know the theory and didn't know if it was true, but it sounded plausible to her. Thank you. Hevesli (talk) 16:57, 1 September 2022 (UTC)
 * So, there are a million complicating factors to consider. From an individual patient point-of-view, we have no way to assess their potential health outcomes from a second infection without knowing what their first infection was like.  Have they fully recovered?  Which strain was each infection?  How healthy are they otherwise, in terms of immune system, lung function, etc. etc. etc.  To say that any one patient can feel safer or not having been already infected by COVID-19 us impossible; only that patient's doctor knows enough about their particular health situation to answer that, and that one patient should get that information from a doctor that can assess their particular unique health situation.  From a public health point of view, the ultimate goal is to minimize transmission in all forms; that's because the virus reproduces by transmission, the more people get it the more opportunities the virus has to mutate, and the more the virus mutates, the greater chance it could mutate into some new strain which could be more resistant to vaccines and treatments, more transmissible, and more deadly.  The mutation rate is of great concern, and so minimizing re-infections can only help public health in that way. On the balance we expect people to be less likely to catch it a second time, and on the balance we expect reinfections to be generally less severe, but those are not the only consideration here, and regardless of whether or not we are talking about a single individual, whose response to a second infection may or may not go the way that the average person does (getting ill in any form always carries risks!), AND from a public health point of view, looking at an entire population, there is no conceivable way in which more COVID infection is beneficial.  -- Jayron 32 18:14, 1 September 2022 (UTC)
 * So one thing that I will say, which may be being confused here, is that there is a concept called the Hygiene hypothesis, for which there is some evidence, which says that exposure to some kinds of pathogens to people early in life may provide for a stronger overall immune system. It's not really that closely related to what you're talking about here, but I can see how someone could extrapolate some of the tenets of the hygiene hypothesis and overapply it to something like what you heard.  -- Jayron 32 18:19, 1 September 2022 (UTC)
 * As an aside, the Hygiene hypothesis really only applies to autoimmune disorders and likelihoods of allergies, from an immune system looking for challenges, not in the other direction of having a "stronger" immune system that is better at fighting off diseases. This whole notion of a "strong immune system" is rooted in concepts of independence and toughness and is one reason people refuse vaccines. Abductive  (reasoning) 23:52, 1 September 2022 (UTC)
 * Yes, thanks for that clarification. I should have made that point stronger.  -- Jayron 32 14:16, 2 September 2022 (UTC)


 * There are two ways to understand the assertion/question.
 * One is whether it is beneficial to deliberately expose oneself to further infection, ceteris paribus. This could be scientifically tested (randomize a group of patients, spray the control group with water and the intervention group with covid-laced water, see if the latter group lives longer/better). The procedure and choice of follow-up period etc. might be simple (by the standards of a clinical trial), but it is likely that getting approval from the relevant ethics committee would be somewhat difficult. While Jayron32 presented informed speculation that it could be beneficial under certain hypotheses it might be beneficial for some individuals under some special circumstances, my speculaguesstimate is that on average and probably in almost all cases it is not: [probability of reinfection by the spraying] times [negative effects of reinfection] is probably higher than [probability the spraying avoids another later infection] times [negative effects of that avoided infection].
 * Another interpretation is that certain actions aimed at avoiding covid infection are on the whole detrimental (at least for some patients). For instance, if you don’t move from your home at all, you might not get covid, but you might get thrombosis. That can also be studied - take a cohort of patients, ask them before and after a study period about their habits, score them on a one-dimensional "covid carefulness" scale, correlate that with healthiness (including covid and non-covid problems). Ethics approval will be easy (the patients just have to fill out a questionnaire), but making a proper protocol and eliminating cofounding variables will be tricky. People who do motorsports / take drugs / do [insert any dangerous activity here] are more likely to have a non-covid health problem than the general population (because of that activity), and also more likely to score low on covid avoidance (because they generally do not worry much about their health). The setting of the study might push people to lie on the questionnaire in a non-uniform manner: for instance, smokers might get into the habit of lying to their physicians about how much they smoke, and that causes some people with a highly-significant medical characteristic (smoking habits) to score fictitiously high on the covid carefulness scale.
 * I think it is unlikely that either interpretation has been studied with enough care about the protocol and statistics to produce a result I would trust, and a quick look at Google Scholar turned up nothing. In the absence of any such study, I am not trusting what you heard at the radio, irrespective of who said it. Tigraan Click here for my talk page ("private" contact) 15:24, 2 September 2022 (UTC)
 * Note, "While Jayron32 presented informed speculation that it could be beneficial" is 180 degrees opposite of what I said. What I said was "regardless of whether or not we are talking about a single individual, whose response to a second infection may or may not go the way that the average person does (getting ill in any form always carries risks!), AND from a public health point of view, looking at an entire population, there is no conceivable way in which more COVID infection is beneficial."  (bold added to quote for clarification).  I'm not sure how you went from my saying there was "no conceivable way in which more COVID infection is beneficial" to me claiming it was.  -- Jayron 32 15:29, 2 September 2022 (UTC)
 * Sorry, I certainly did not meant that you advocated for the infection policy, and I do not think anything you wrote was unreasonable (otherwise I would have said so). I have struck that part and put something in my own words.  Tigraan Click here for my talk page ("private" contact) 15:43, 2 September 2022 (UTC)
 * It's all good man. Yeah, individual health outcomes are, well, individual, and to say that zero people would benefit from reinfection is different from saying that, as a matter of either public health policy or medical best practice, intentional reinfection should be recommended.  Could we find at least one person on the planet who had a better health outcome because they were so reinfected?  I have no doubts we could.  Does that mean policies should be changed to advocate for that?  Hell-to-the-effing-no, because there are far more important considerations than any potential benefits to a single person.  -- Jayron 32 15:57, 2 September 2022 (UTC)
 * @Tigraan and others... instead of spraying one group with covid-laced water, supposedly to give them more antibodies, why not give them (another) booster vaccine? It seems that's what the original question is trying to get at... 71.228.112.175 (talk) 01:29, 7 September 2022 (UTC)
 * Actually, the OP asked specifically about "not being careful" and intentionally being in "contact with an infected person" (their words). That's not a booster shot.  Those of us that responded provided answers to the questions actually asked.  Your question involving booster shots is a different question.  -- Jayron 32 14:39, 7 September 2022 (UTC)

Time between successive COVID-19 illnesses
A related question. After recovering from COVID-19, the healed patient can fall ill again, but not immediately. How much time is left between at least? Thank you. Hevesli (talk) 16:59, 1 September 2022 (UTC)
 * As far as I know, there is no guaranteed minimum time limit between reinfections with COVID-19, indeed if we are dealing with substantially different strains, a person can be reinfected in fairly short order; or even be infected by multiple strains simultaneously, see here. -- Jayron <b style="color:#090">32</b> 18:07, 1 September 2022 (UTC)


 * Coronavirus (COVID-19) Infection Survey, characteristics of people testing positive for COVID-19, UK: 20 July 2022 notes that reinfection with the Omicron variant was five times more likely than with previous variants (in the UK). Alansplodge (talk) 12:52, 2 September 2022 (UTC)