Wikipedia:Reference desk/Archives/Science/2022 March 3

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March 3

Medical term for multiple diagnoses

What is the term when a hospital patient has multiple diagnoses or ailments, I have heard it before it is not "multi" or anything like that. I am having a brain hiccup here. Thanks in advance!2600:1702:690:F7A0:E8C4:93D8:8565:9D61 (talk) 03:49, 3 March 2022 (UTC)

Comorbid.  Card Zero  (talk) 03:52, 3 March 2022 (UTC)

A thousand thanks! It is strange what the brain just won't remember, much appreciation!2600:1702:690:F7A0:E8C4:93D8:8565:9D61 (talk) 05:05, 3 March 2022 (UTC)

And the corresponding noun is comorbidity, on which we have an article.  --Lambiam 09:55, 3 March 2022 (UTC)

Sand shortage

In future, there will be no sand for construction?

https://www.dw.com/en/sand-crisis-shortage-supply-mafia/a-56714226

https://www.bbc.com/future/article/20191108-why-the-world-is-running-out-of-sand --Knight Skywalker (talk) 07:23, 3 March 2022 (UTC)

To a certain extent, sand that is usable as construction aggregate is a renewable resource, but it appears to be used up faster than it is being replenished. Much use of sand, in particular in making concrete, can be replaced by crushed stone, but (depending on the local circumstances) this may be more expensive. As sand gets scarcer and more expensive, the relative share of other forms of construction aggregate (including recycled aggregate from demolition and such, now often treated as waste) will increase. Also, more use can be made of wood and bricks in constructing buildings. So this does not have to be a yes-or-no thing.  --Lambiam 09:50, 3 March 2022 (UTC)

Recycled sands are an environmentally friendly, cost effective alternative to natural dug sand. Sourced from crushed concrete, crushed glass or re-used sand, recycled sands are sustainable products that reduce waste to land-fill. [1] Alansplodge (talk) 18:07, 3 March 2022 (UTC)

How analog video signal converted to raster scan?

I understand this is how structure of analog video signal look like.

But how this structure converted to Raster scan? Rizosome (talk) 20:06, 3 March 2022 (UTC)

@Rizosome: Appropriate discriminator circuits are able to detect parts of the signal as synchronization for vertical and horizontal scan. Those trigger/synchronize the deflection signal generators and ...that's it.
For more details you may see Cathode-ray tube, especially the #Deflection section. --CiaPan (talk) 20:34, 3 March 2022 (UTC)

I got the answer from this line: Appropriate discriminator circuits are able to detect parts of the signal as synchronization for vertical and horizontal scan. Rizosome (talk) 11:58, 4 March 2022 (UTC)

Resolved

I highly recommend the YouTube channel Technology Connections. He's got a very good series on video technology, and goes into excellent detail. He's easy to understand, and has an absolutely biting sense of humor. --Jayron32 12:07, 4 March 2022 (UTC)

Localized rain around trees

Hello! So recently, in the town I live in (i'm not going to say what town I live in cause that's personal info) it just started raining, however it only seemed to be raining around the trees. I could tell that it wasn't just because the trees got wet because there hadn't been any rain that day. What's causing this strange phenomenon and why is it only raining around the trees? ― Blaze Wolf^Talk_{Blaze Wolf#6545} 22:22, 3 March 2022 (UTC)

Fair enough if you live in a small town to keep it hidden, but it would help to have some idea. Hot or cold? Maritime or continental? Which continent? Maybe even the approximate latitude? All we know for certain is that you are not in Antarctica since they don't have trees there. Martin of Sheffield (talk) 22:27, 3 March 2022 (UTC)

I'm in the United States. Hot or cold... well it depends on the season. Usually in Winter it's cold (although towards the end of Winter it does start warming up a bit). ― Blaze Wolf^Talk_{Blaze Wolf#6545} 22:31, 3 March 2022 (UTC)

When you say "around" the trees, do you mean it's only wet outside the tree's canopy? Or it's only wet under the tree's canopy? --←Baseball Bugs ^{What's up, Doc?} carrots→ 22:41, 3 March 2022 (UTC)

Under the tree's canopy (which is just branches cause it's Winter). Apologies for my vagueness there. ― Blaze Wolf^Talk_{Blaze Wolf#6545} 22:44, 3 March 2022 (UTC)

Possibly Honeydew (secretion)? But I'm not sure if an aphid infestation is likely in Winter.  Card Zero  (talk) 00:04, 4 March 2022 (UTC)

I highly doubt it would be that. There were visible rain drops. I'm unsure of what type of tree it is though. To my knowledge it doesn't produce any sort of seeds or fruit or anything. ― Blaze Wolf^Talk_{Blaze Wolf#6545} 00:09, 4 March 2022 (UTC)

I've had that happen too. I suspect condensation. Since we are warm-blooded, we can't have condensation occur on us, meanwhile ambient-temperature objects are having dew condense on them all around us. Trees have a lot of surface area, and then, with a little bit of wind, sprinkles. Abductive (reasoning) 06:29, 4 March 2022 (UTC)

Caution! WP:OR !

I live in a big city in the central Poland in the central Europe, and have seen - and experienced - this phenomenon multiple times. When it is quite warm and a cold and humid night comes, the fog forms and then condensates on trees' leaves. When you walk under a tree you can actually experience a 'rain' - well, single droplets - falling from the tree. The roads and pavements look dry, as the humidity does not condense on their relatively warm surface, but the areas under trees become dark, wet from droplets. If it was really cold, below 0°C, there would be no tree-rain, instead trees would dress in a spectacular frost. --CiaPan (talk) 08:04, 4 March 2022 (UTC)

It sounds like you are observing dewfall. The tree's temperature will approach ambient towards the end of the night (it can take quite a while to cool, wood is an insulator). If you have had a cold night and then the temperature rises as the day starts, and the air is moist, then the air immediately adjacent to the branches may become supersaturated and water will condense out. The moisture will run down hill until such a time as it gathers into large enough drops to fall. If you've ever observed the cistern of a toilet in a steamy room, such as a bathroom, you'll see the same effect. Martin of Sheffield (talk) 09:21, 4 March 2022 (UTC)

That's probably what happened! IT was super warm the previous day (~70*F) and then the next it cooled off drastically. There was also some fog that stuck around for a while earlier that day. ― Blaze Wolf^Talk_{Blaze Wolf#6545} 20:35, 4 March 2022 (UTC)

Aha! Fog indicates that the air was saturated. On a colder surface it would become super-saturated and condense. Martin of Sheffield (talk) 23:05, 4 March 2022 (UTC)

Cool! Glad to finally have an explanation. ― Blaze Wolf^Talk_{Blaze Wolf#6545} 23:14, 4 March 2022 (UTC)