Wikipedia:Reference desk/Archives/Science/2020 March 5

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March 5

coronavirus immunity

Do people infected with CV and recover from it become immune, like with some other viral illnesses? If this is not known, does it happen with regular flu? I'm wondering if antibodies from immune people can be used to treat infected people, as was apparently done with Ebola. Don't worry I'm not going to try this at home. Thanks. 2602:24A:DE47:B270:A096:24F4:F986:C62A (talk) 01:09, 5 March 2020 (UTC)

It seems to be too early to tell.[1] ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:19, 5 March 2020 (UTC)

Thanks. I wonder how many post-recovery positive tests were people who weren't re-infected, but rather, never became non-infected (they beat back the virus enough to stop having symptoms, but not enough to get rid of it completely, like supposedly can happen if you don't take your full course of antibiotics for bacterial infections). To really detect re-infection we'd need to see a positive test followed by a negative test followed by a positive test, all in the same person. There also appear to be two strains of the virus going around now, so they'd have to distinguish them. 2602:24A:DE47:B270:A096:24F4:F986:C62A (talk) 01:45, 5 March 2020 (UTC)

https://www.dfa.co.za/international-news/japanese-woman-tests-positive-for-the-coronavirus-for-a-second-time-43594564 — Preceding unsigned comment added by 94.198.187.35 (talk) 10:33, 6 March 2020 (UTC)

A recent mutation of the virus may complicate things. Count Iblis (talk) 11:28, 6 March 2020 (UTC)

In general, the only way a body recovers from an infection is by obtaining an immunity to it. As opposed to, for example, poisons, which may or may not have varying tolerance levels. 73.222.115.101 (talk) 19:34, 7 March 2020 (UTC)

Wuhan coronavirus in New Zealand

To what extent is the Wuhan coronavirus a problem in New Zealand? Asking again as the situation is changing rapidly. Freeknowledgecreator (talk) 01:31, 5 March 2020 (UTC)

2020 coronavirus outbreak in New Zealand. 2602:24A:DE47:B270:A096:24F4:F986:C62A (talk) 01:43, 5 March 2020 (UTC)

Excavation methods

Are pneumatic caissons used as an alternative to the standard Piling, use of excavators and temporary retaining structures in large scale excavations? 126.255.11.145 (talk) 04:40, 5 March 2020 (UTC)

Have you seen Caisson (engineering)#Pneumatic? I saw some more detailed information here. If that does not answer your question, can you be more specific, in particular as to what engineering purpose the large scale excavation would serve?  --Lambiam 08:05, 5 March 2020 (UTC)

• Well, they're certainly used and would still be an alternative.

In the modern period, pneumatic caissons are used less than they used to be, in favour of larger open-topped caissons. The availability of powerful cranes means that a large caisson (i.e. large enough to reach the surface) is both more easily installed, and crane access from above is obviously useful. Health and safety aspects also discourage working under pressure. Also working with bulk materials in a pneumatic caisson was infamously difficult, as they mostly relied on manual effort to move and lift things and spoil removal / material supply was awkward through the lock.

If a pneumatic caisson was used to gain access to the bottom, that has largely been replaced. If a pneumatic caisson was used because access to the bottom still needed to be under pressure (i.e. water would flood in otherwise), those are still used.

Furthermore, open water diving has become more sophisticated. Tasks which might once have needed a caisson to work in are now being done underwater. Andy Dingley (talk) 15:07, 5 March 2020 (UTC)