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February 26

Industrial-strength lamb fat?!

A couple weeks ago, I put a plate of food with a dish containing curry and lamb outside in the cold (my refrigerator was broken, and I know that this was an unsafe practice; I will not be asking for any professional advice based on this fact, just a scientific query about fat residue). Shortly after, the food was exposed to the elements: sun, rain, and a raccoon. Recently, I took the food back inside, dumped all the expired contents, and washed it immediately in hot water and dish soap. Much to my surprise, there was a layer of fat residue on part of the inner side of the plate that would not come off! I tried scrubbing it with different kinds of soap, running it through both hot and cold water again, scrubbing it with my fingers, but to no avail. My fingers merely left print marks on the fat as I was scrubbing it, and when I smelled it, it still had the faint odour of freshly cooked lamb. The fat was white with a yellowish tint, very thick, and may have reduced the friction coefficient on my hands after I washed them (although I'm not entirely sure about this one).

I have two questions:

1) What possibly could have caused the lamb fat to procure an industrial-strength durability?! I do not recall the plate being this hard to wash right after putting the lamb dish in it, if I had tried transferring it to another plate and washing the first one.

2) What chemical or technique can I use to remove the fat from the edge of the plate? Am I better off throwing out the whole plate? (I'm playing it safe here, and assuming that the plate is only safe when all surfaces are disinfected by heat, without residue of any kind that could harbour pathogens -- again, I'm not asking for any professional advice related to this, medical or otherwise).

Thanks. (I live in Canada, where the temperature at night can easily drop below -10C Centigrade).

2607:FEA8:1DDF:FEE1:1C3F:96A8:802D:5407 (talk) 06:48, 26 February 2020 (UTC)[reply]

I don't know about the first question. I could speculate, but I'll leave that for others.

Soap can be used to remove fat because it works as an emulsifier. If that's not good enough, you can try a stronger base, like ammonia solution or even sodium hydroxide solution. Bases act on the fat by breaking it down into glycerol and fatty acids, which tends to be rather effective. But bases have a tendency to dissolve aluminium, so if you're dealing with an aluminium plate, better try something else. PiusImpavidus (talk) 09:25, 26 February 2020 (UTC)[reply]

Did you leave it to soak in soapy water for a while? ←Baseball Bugs ^{What's up, Doc?} carrots→ 11:57, 26 February 2020 (UTC)[reply]

I'd suggest (a) scraping off as much of the fat as possible with a thin knife blade followed by (b) re-heating the plate to liquify the residue before recleaning it with hot water and soap/detergent. You don't mention the composition of the plate, but if it's conventional glazed porcelain without cracks or pores it shouldn't have actually absorbed any of the fat – that's why tableware is made from porcelain. {The poster formerly known as 87.81.230.195} 90.202.162.227 (talk) 13:47, 26 February 2020 (UTC)[reply]

I would suggest NOT to heat a ceramic plate by conventional means, lest the OP wants to explore the wonderful world of thermal shock and fracture mechanics. Same advice for plastic (because of the absolute temperature rather than the gradient though). Maybe microwaving could work in heating the residue rather than the plate, but whether it will be enough to make it come loose is another question. Tigraan^{Click here to contact me} 17:04, 27 February 2020 (UTC)[reply]

If the plate is plastic, I would not rule out some kind of weird chemical reaction between the decomposing fat and plastic itself. --Jayron 32 12:59, 27 February 2020 (UTC)[reply]

I usually wipe fat like that off with a paper towel, it seems to get almost all of it off, then wash in hot water and detergent.49.197.54.240 (talk) 05:51, 28 February 2020 (UTC)[reply]

Books about chemistry

Can anyone recommend me some not too hard to read, Brian Greene type books about chemistry? I was reading Feynman's Lectures on Physics and was intrigued by the description in the introduction of how chemistry uses macroscopic methods (colors of substances etc.) to understand in an "unexpected" way the microscopic structure of a compound, and I'd like to learn a little more about that. Thanks! 95.168.116.25 (talk) 18:39, 26 February 2020 (UTC)[reply]

Our Category:Science communicators sadly isn't disaggregated by branch of science. Category:Popular science books is, but from a cursory glance, has nothing about chemistry. So, for now, and pending a better answer (I feel like this Q deserves one), take a look at this list on GoodReads. Aecho6Ee (talk) 19:14, 29 February 2020 (UTC)[reply]

Thanks, I've borrowed Uncle Tungsten, might not be what I was going for but I'm a big fan of Sacks so it's so far an entertaining read anyway! 93.136.1.34 (talk) 20:47, 2 March 2020 (UTC)[reply]

looking for CPSS or CSS info (UPS-style device) and interlanguage wikilink

hi, please see Talk:Uninterruptible_power_supply#looking_for_CPSS_or_CSS_info

thank you.

--5.170.45.195 (talk) 20:10, 26 February 2020 (UTC)[reply]

Java Sea shape

What kind of geological processes have led to Java Sea's current shape? I've just noticed it seems oddly rectangular. 89.172.8.50 (talk) 23:51, 26 February 2020 (UTC)[reply]

The tectonics of Indonesia is very complex, and the processes that gave rise to this specific shape are probably best described in terms of randomness. (Explain why Italy is a high lady boot kicking a deflated football named Sicily.) Contributing factors are also the desire of hydrographers to assign neat boundaries to somewhat arbitrary partitions, and our bias to seeing patterns and familiar shapes that have no objective existence. When viewing this on a blind map, the alleged rectangularity is not particularly striking. --Lambiam 09:05, 27 February 2020 (UTC)[reply]

Offtopic, but Pareidolia is probably a better link than Reification (Gestalt psychology) here. Tigraan^{Click here to contact me} 16:55, 27 February 2020 (UTC)[reply]

What do tectonics have to do with the Java Sea? It's relatively recent, formed by the submerging of a limestone plateau at the end of the last Ice Age. The shape, and its simplicity, is largely random, but also a combination of some coasts which are lacking in large estaurine features, together with large sea boundaries which are simply drawn as straight lines, and mostly perpendicular to the coasts. Andy Dingley (talk) 19:47, 27 February 2020 (UTC)[reply]

Lambiam is onto it. Our brains tend to try to make sense of random things, and sometimes sees things that just happen to remind us of something. The Man in the Moon is an obvious example. ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:11, 27 February 2020 (UTC)[reply]

Sorry, I should've added the picture. It's more obvious in this picture on the right or the one here: Indonesia#Administrative_divisions. Look at the coasts of Lampung, Banten and West Java province for the best match. The right side of the quadrangle in the Java Sea picture requires drawing two imaginary lines from Celebes but the other three sides seem fairly obvious to me. My first thought was also tectonics, but Borneo, Java and Sumatra are all on the same plate. Amusingly the angle between Banten & Lampung coasts at the Sunda strait matches the angle of the southwest corner of Borneo (my crude measurements [1] give 98.8° and 98.9° for the angles). Altho that one can only be a coincidence considering that the rest of the coast doesn't match. 89.172.8.50 (talk) 21:04, 27 February 2020 (UTC)[reply]

The forces of nature can do most anything. Note the likewise vaguely rectangular shape of the Hawai'ian island called Moloka'i. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:35, 27 February 2020 (UTC)[reply]

Both that example and the one this section is about are primarily created by current sea levels. Ten metres higher or lower and the shapes may well be very different. Perhaps the question should be why the sea level is what it is today. HiLo48 (talk) 21:43, 27 February 2020 (UTC)[reply]

February 27

Location of Fukushima reactor

I've been trying to find information regarding the location of the Fukushima Daiichi Nuclear Power Plant, mainly why it was built in that particular location. Currently, my best guess is that there wasn't strong opposition to the plant in that location and the Sea of Japan provided a suitable cooling source, but it's been a struggle to find any reliable sources. Any ideas?
5225_C (talk) 06:32, 27 February 2020 (UTC)[reply]

On the coast, you mean? Nuclear reactors were often built on coastlines and riverbanks because the designers assumed a catastrophic breach would be more likely to be washed away than could be accomplished from an inland site. While there may be merit to that idea in general, a catastrophic meltdown will still deposit the worst contamination in a literally melted cavern under the reactor core, surrounded by molten steel and concrete, usually without any real chance to wash it into the water. Seawater brine can't be used as a nuclear reactor coolant directly, because it's corrosive and difficult to filter, but it can be used to carry away heat from heat exchangers in cooling ponds, or in Fukushima Daiichi's case, directly on the coastline. This journal article suggests that its siting and hazard studies prior to construction were severely flawed to begin with. This article (in Japanese) covering the court case outcomes, is said to describe the duty of care that TEPCO observed in siting the plant as less stringent than that required of an ordinary automobile driver, because the company, regulators, and their PR agencies had perpetuated a "myth of safety" squelching legitimate questions about risks with an onslaught of misleading claims and attitudes about the likelihood of accidents. EllenCT (talk) 09:42, 27 February 2020 (UTC)[reply]

The primary cooling system used seawater for exchanging heat,[2] so the proximity to the sea must have been a consideration in the selection of the site. The book Fukushima: The Story of a Nuclear Disaster relates how overconfidence played a role: “When construction began on the reactors in the late 1960s, engineers dismissed the likelihood that the plant location might be vulnerable. Based on the worst historical tsunami on record at the Fukushima site—resulting from a 1960 earthquake in Chile—the reactors were designed to withstand a tsunami with a maximum height of about ten feet (3.1 meters). TEPCO was so confident of this data point that the company actually lowered the height of the bluff where the plant was to be built by more than eighty feet (twenty-five meters).” [3] --Lambiam 09:46, 27 February 2020 (UTC)[reply]

The identification of the 869 tsunami - work published in 2001 - gave them ample time to reconsider the design, but ten years later nothing had been done to mitigate this risk. Mikenorton (talk) 05:48, 1 March 2020 (UTC)[reply]

@5225C: also, it's on the Pacific Ocean, not the Sea of Japan, although colloquially of course, "sea of Japan" certainly includes the surrounding oceans. EllenCT (talk) 22:37, 2 March 2020 (UTC)[reply]

Yeah, I noticed that a couple hours after I posted it. My bad, but thanks for clarifying!
5225_C (talk) 23:24, 2 March 2020 (UTC)[reply]

Natural photograph

Is there a process which spontaneously results in a picture of an object being imprinted on something, maybe in the manner of the camera obscura? Is there an instance of this having happened? Regrettably, the closest to this I can think of are shadows created by the atomic bomb in Hiroshima and Nagasaki. 93.142.73.32 (talk) 23:54, 27 February 2020 (UTC)[reply]

You can make an image on a plant leaf using the chemistry of photosynthesis.[4] As described in the article, this is not a spontaneous process and only partly natural. A similar process, based on drying leaves losing their colour, can also be used to produce images, without chemical postprocessing.[5] The opposite effect is that leaves need light to turn green, so an image should eventually also appear on a leaf from being covered by a negative for a long period of time. For this process to result in a spontaneous chlorophyll print, some flattish object should accidentally come stuck on top of a leaf, eventually leaving a yellowish mark in its shape. I bet this happens all the time, but I know of no actual instances. --Lambiam 08:35, 28 February 2020 (UTC)[reply]

Cool, not quite what I was going for but I'll have to try this out next fall! 93.142.73.32 (talk) 22:16, 28 February 2020 (UTC)[reply]

I forgot to say what inspired me was things like Archaeoacoustics#Past_interpretations_controversy, altho it looks like that was disproved later. 89.172.73.94 (talk) 00:09, 29 February 2020 (UTC)(OP)[reply]

Does Permineralization#Pyritization count? Tigraan^{Click here to contact me} 09:28, 28 February 2020 (UTC)[reply]

Does it produce a 2D result? IDK much about fossils, but from what I understood they're more like natural sculptures, not photographs. That's still pretty amazing tho now that I think about it. 93.142.73.32 (talk) 22:16, 28 February 2020 (UTC)[reply]

The most common occurance I've seen has been when there is a thin layer of snow on the ground, and the the sun shines for a half hour before it becomes overcast again. An image of the house's shadow is left imprinted where the snow was not melted due to the house being in the way. It can be quite a detailed and accurate image unless the sun stays out and melts it.Edison (talk) 13:30, 3 March 2020 (UTC)[reply]

February 28

How do cells direct production of specific proteins?

I understand how genes are read and messenger RNA produced, travels to ribosomes and voila, a protein. But how does the other side work? If a cell "knows" it needs a particular protein how does it start the process. How does a particular gene on a particular chromosome get told to start the transcription process? — Preceding unsigned comment added by 60.240.95.248 (talk) 04:00, 28 February 2020 (UTC)[reply]

There is no single mechanism and scientists are still making new discoveries, so the question does not have a simple answer. But you can get an idea by reading Regulation of gene expression and following links to various subtopics. --Lambiam 08:44, 28 February 2020 (UTC)[reply]

February 29

Nitrogen narcosis

Why one still gets nitrogen narcosis if per Breathing gas, "most breathing gases [...] are a mixture of oxygen and one or more inert gases", ie similar or identical to air? The narcosis article says high pressure is involved, but I still don't understand why when the breathing mix is basically air and not a pure nitrogen. 212.180.235.46 (talk) 21:44, 29 February 2020 (UTC)[reply]

I think the main difference is solubility. Nitrogen dissolves in blood at high pressure; helium not so much. So a breathing gas made with helium replacing some or all of the nitrogen reduces the risk of nitrogen narcosis (and also of the bends, a separate issue but also caused by nitrogen). --Trovatore (talk) 21:48, 29 February 2020 (UTC)[reply]

Ok, would this still be an issue if you lower nitrogen percentage in the mixture? Instead of air-like 78% of nitrogen, say 10% nitrogen and 90% oxygen? Or 5%? 212.180.235.46 (talk) 00:01, 1 March 2020 (UTC)[reply]

Not sure of the exact numbers, but at high pressures even oxygen can become toxic. --Khajidha (talk) 00:11, 1 March 2020 (UTC)[reply]

Oxygen is somewhat toxic in higher-than-normal concentrations even at normal atmospheric pressure, as well as a fire hazard. See oxygen toxicity. (The astronauts who died in the Apollo 1 launch-pad fire were breathing pure oxygen at slightly above normal atmospheric pressure, because that was the only way the test they were performing could be done in an Apollo capsule, but were safe from toxicity because at such pressures the damage to the body is slow to develop.) --69.159.8.46 (talk) 03:57, 1 March 2020 (UTC)[reply]

Oxygen by itself is not a fire hazard, it depends on what else is there. ←Baseball Bugs ^{What's up, Doc?} carrots→ 15:37, 1 March 2020 (UTC)[reply]

Yes, where "what else" is "anything that will burn". --69.159.8.46 (talk) 19:31, 2 March 2020 (UTC)[reply]

From skimming the article, it appears that it is the partial pressure of the N₂ that determines whether it has a narcotic effect (and how severe). So yes, decreasing the proportion of N₂ in the air mix will reduce the effect (while going deeper, and therefore increasing the pressure, will increase it). Iapetus (talk) 20:12, 1 March 2020 (UTC)[reply]

"Inert" gas narcosis a function of the gas' narcotic potential and partial pressure, not concentration. It certainly is possible to reduce nitrogen narcosis by replacing nitrogen with something less narcotic although this would typically be helium, not oxygen. 2A01:E34:EF5E:4640:4CB5:BD3F:EC15:C20A (talk) 18:53, 1 March 2020 (UTC)[reply]

The Breathing gas#Oxygen article discusses the risk of oxygen toxicity. The article specifically mentions

The fraction of the oxygen determines the greatest depth at which the mixture can safely be used to avoid oxygen toxicity. This depth is called the maximum operating depth.[1][3][6][9]

and

The maximum safe P_O₂ in a breathing gas depends on exposure time, the level of exercise and the security of the breathing equipment being used. It is typically between 100 kPa (1 bar) and 160 kPa (1.6 bar); for dives of less than three hours it is commonly considered to be 140 kPa (1.4 bar), although the U.S. Navy has been known to authorize dives with a P_O₂ of as much as 180 kPa (1.8 bar).[1][2][3][6][9] At high PO2 or longer exposures, the diver risks oxygen toxicity which may result in a seizure.[1][2] Each breathing gas has a maximum operating depth that is determined by its oxygen content.[1][2][3][6][9]

and

where the oxygen content exceeds atmospheric levels, generally to a level where there is some measurable physiological effect over long term use, and sometimes requiring special procedures for handling due to increased fire hazard. The associated risks are oxygen toxicity at depth and fire, particularly in the breathing apparatus.[citation needed]

Our Gas blending for scuba diving also discusses oxygen toxicity although mostly just says similar stuff.

We even have a Maximum operating depth article which mentions

This limit is based on risk of central nervous system oxygen toxicity, and is somewhat arbitrary, and varies depending on the diver training agency or Code of Practice, the level of underwater exertion planned and the planned duration of the dive, but is normally in the range of 1.2 to 1.6 bar.[1]

In case it's unclear from these, Enriched Air Nitrox and Trimix (breathing gas)#Hyperoxic trimix are used in certain circumstances. But obviously just increasing the oxygen concentration does not work for many cases.

BTW, you might also be interested in Trimix (breathing gas)#Advantages of keeping some nitrogen in the mix, High-pressure nervous syndrome, Trimix (breathing gas)#Disadvantages of helium in the mix, Compression arthralgia and Decompression sickness. The effect of using helium on the risk of decompression sickness, is different from what I had understood until now, and I wonder if User:Trovatore may also share some confusion in the area. Likewise, I wasn't aware of the other reasons besides cost why you may not want to just use heliox.

BTW, despite that one citation needed tag, our articles look in decent shape albeit I haven't checked the quality of the references and do not know about the subject. I.E. I'm just assuming from the referencing and writing it's not utter nonsense.

One example, I noticed our article mentions

Helium dissolves into tissues (this is called on-gassing) more rapidly than nitrogen as the ambient pressure is increased. A consequence of the higher loading in some tissues is that many decompression algorithms require deeper decompression stops than a similar decompression dive using air, and helium is more likely to come out of solution and cause decompression sickness following a fast ascent.[9]

Yet I came across [6] which makes me think there may be some dispute over what is necessary and why. But this is also very recent, and I have no idea how well accepted it is.

Nil Einne (talk) 15:50, 2 March 2020 (UTC)[reply]

The classic "decompression accident" is related to off-gassing the gas dissolved in the diver's body and, for this purpose, only inert gases are considered since the oxygen is assumed to have been metabolized.

For "inert" gas narcosis, oxygen is often, but not always, taken into account (narcotic potential is predicted by the meyer-overton law which suggests that oxygen should be more narcotic than nitrogen at the same partial pressure). So, binary mixes like nitrox are sometimes considered either less nacotic than, or identically narcotic to, air (The principal advantage of nitrox is to reduce nitrogen loading but at the cost of an increased oxygen stress).

Binary mixes like triox are preferred at depths between 30m and 40m where the narcotic potential of nitrox may be considered excessive. In principle it would be possible to extend the use of triox to greater depths by using lower and lower oxygen fractions, but the cost of the helium becomes prohibitive so trimix is generally preferred.

There are two forms of oxygen toxicity, the one which concerns divers being related to the integral of oxygen partial pressure with respect to time.

At sufficient depth, a breathing mix with a safe oxygen partial pressure would be dangerously hypoxic (I've used mixes with only 4% oxygen), in which case one or more separate "travel" gases are required for the initial shallow portions of the dive.

37.175.103.191 (talk) 17:34, 2 March 2020 (UTC)[reply]

March 1

Coronavirus concern

The world is in panic about the Coronavirus. Scientifically speaking, why should the world should be very concerned about the Coronavirus epidemic if the fatality rate is about 2% [7] [8]? And especially if young and healthy kids and millennials get it if the fatality rate is not existent for these groups? Other kinds of viruses have higher fatality rates than the Coronavirus. Scientifically speaking, help me understand why the Coronavirus is of grave concern. 2600:1006:B050:FEA4:ACC5:C31D:DCF3:63A3 (talk) 08:26, 1 March 2020 (UTC)[reply]

Spanish flu had a similar mortality rate, and killed around 50 million people (from a substantially smaller global population with much less global traffic). Whether that's of "grave concern" to you personally is up to you, of course, and may depend on your relative evaluation of pensioners and millenials. Henry ^Flower 08:55, 1 March 2020 (UTC)[reply]

Spanish flu had a 8-20% mortality rate based on Wikipedia article. A far cry from 2% or even a fair bit lower if there are many asymptomatic/weakly symptomatic cases which would explain the numerous outbreaks. 89.172.75.199 (talk) 01:11, 2 March 2020 (UTC)[reply]

Which part of the article are you reading? The Mortality section says The World Health Organization estimates that 2–3% of those who were infected died. Henry ^Flower 09:36, 2 March 2020 (UTC)[reply]

The intro says 40-100 million out of 500 million infected. 40-100 million was more than 2-3% of the entire planet's population at that time, let alone the number of infected, so WHO must've been working with different death figures. 93.136.1.34 (talk) 20:35, 2 March 2020 (UTC)[reply]

True. Looking at the talk page, there's been a bit of discussion about the discrepancy, going back at least ten years. I'm not reading all that, but the upshot seems to be that nobody was really counting at the time, so guesses vary wildly. Henry ^Flower 22:10, 2 March 2020 (UTC)[reply]

The Guardian did a recent piece entitled Yes, it is worse than the flu: busting the coronavirus myths. I don't know how accurate the points in at are, but at least it's a reasonably reliable source. AndrewWTaylor (talk) 09:38, 1 March 2020 (UTC)[reply]

If the viral load is relatively high, then the virus may kill even young persons, that's why Li Wenliang, for example, died at just 33 years. But, perhaps more importantly, infected persons may spread the virus to people with weak immune systems, including elder persons (potentially someone's grandparents, etc). And that's not good. These projected scenarios may be of interest. Brandmeister^talk 09:42, 1 March 2020 (UTC)[reply]

If nothing is done to slow down the spreading, health and sanitation systems will be overwhelmed and dead bodies will be lying in the streets of major cities, like happened with the 1918 influenza pandemic and earlier this year in Wuhan. Not only is the death rate of infected people maybe 20 times that of seasonal influenza, but the World's population has virtually no immunity of any kind against the novel coronavirus – unlike for most kinds of influenza viruses. The pro capita mortality would therefore be much higher. On the other hand, only drastic or even draconic measures will cause a significant slow-down, but these also have a dramatic effect on the economic productivity. --Lambiam 14:00, 1 March 2020 (UTC)[reply]

Citation needed on "dead bodies will be lying in the streets of major cities, like happened with the 1918 influenza pandemic and earlier this year in Wuhan": Corpses of Wuhan Coronavirus Patients Dumped on Roads? Fake Alert 93.136.1.34 (talk) 20:35, 2 March 2020 (UTC)[reply]

The OP's "only" 2 percent sounds like General Turgidson: "I'm not saying we won't get our hair mussed..." ←Baseball Bugs ^{What's up, Doc?} carrots→ 15:34, 1 March 2020 (UTC)[reply]

I asked because I saw the stats, but I don’t know much about the Coronavirus. 2600:1006:B050:FEA4:ACC5:C31D:DCF3:63A3 (talk) 18:24, 1 March 2020 (UTC)[reply]

Nor does hardly anyone else, and that feeds the "panic". The flu is bad, but it's a known quantity. This thing still has too many question marks. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:46, 1 March 2020 (UTC)[reply]

"if young and healthy kids and millennials get it if the fatality rate is not existent for these groups". Large numbers of people are not "young and healthy kids and millennials". I'm not sure why so many people seem to think that a disease that kills people who are already ill, and the elderly/middle-aged, is no big deal. And in a worst case scenario of 100% contagion, that means killing off 2% of the Silent Generation, Boomers, Gen X, and unhealthy millenials and kids, which is a huge number of deaths, with every family losing people. Iapetus (talk) 20:34, 1 March 2020 (UTC)[reply]

It's not that it's not a big deal, it's that many things have a disproportionate mortality on those groups, including the flu, other coronaviruses, and other respiratory illnesses. Although deaths in those groups are a tragedy, they're not unexpected, even without some specific trigger. Deaths to otherwise healthy young adults is a) unexpected b) a greater burden on the economy and c) a greater burden on the healthcare system, both because higher numbers of people need treatment and because more of the staff will be directly affected. Matt Deres (talk) 15:15, 2 March 2020 (UTC)[reply]

As pointed out here::

"The danger posed to society from this disease doesn't come from the mortality rate, rather from the potential to make large fraction of the population ill. Unlike the flu virus, this virus is a new virus to which we have no immunity.

About 10% of the infected people requires hospital treatment, which is a lot higher than in case of flu. The death rate of the order of 1% is achieved thanks to excellent hospital treatment. With a far larger fraction of the population infected with this virus compared to the flu and a far larger fraction of the infected people requiring hospital treatment compared to flu, the available hospital capacity to give everyone the treatment they need can be easily exhausted. The death rate due to the virus will then increase.

Also, people who need treatment for other reasons can then also fail to get prompt medical attention. People suffering a heart attack who would have survived under normal circumstances thanks to getting prompt medical attention, may now end up dying too." Count Iblis (talk) 01:38, 2 March 2020 (UTC)[reply]

If you back up a bit and look at media representation, you get a different view. Why is the coronovirus all over world media? Because it gets attentiona and that attention sells advertising. If you present it just right, you can get a lot of play out of the coronovirus. Include pictures of land sharks with rabies and I bet you can get more play out of it. This doesn't mean that the coronovirus is not a threat. It means that the threat of it and the media coverage of it are not necessarily related to one another. Terrible things have gone uncovered. Benign things have been covered ad nauseam. 135.84.167.41 (talk) 12:51, 2 March 2020 (UTC)[reply]

The coronavirus is not "benign". And it's too early to say with certainty how big of a threat it is or what its mortality rate will turn out to be. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:29, 2 March 2020 (UTC)[reply]

It's in the media because it currently has a 2000% higher kill rate than the flu, (COVID-19 has about a 20 per 1000 kill rate, where as the flu has about a 1 per 1000 kill rate) and the flu already kills a lot of people. --Jayron 32 18:05, 2 March 2020 (UTC)[reply]

You are comparing the death rate for those diagnosed in a medical facility with COVID19 to the death rate of all people estimated to get a flu infection - including those who show little to no symptoms. If you increase the COVID19 denominator to all those infected who show little to no symptoms, the death rate will be far lower - and sell less advertising if you were producing a media segment. 135.84.167.41 (talk) 18:23, 2 March 2020 (UTC)[reply]

You have fun living in your little world where diseases don't matter and bury your head in the sand. Have fun with that. Me, I'm going to wash my hands and try to stay away from people actively sneezing on me. --Jayron 32 18:54, 2 March 2020 (UTC)[reply]

March 2

modern processors

out of curiosity, what is the minimum amount of external circuitry needed to make a modern PC processor work? it doesn't have to work well or fast, just do something minimally useful like say fetching instructions from a (static, parallel) RAM and executing them. I'm thinking of things like PIC and AVR (that are µC), that need only a supply voltage and an optional clock, with not very high requirements (wrt stability etc) for either. I think things like the Z80 didn't need much external logic either. To put it bluntly, is all of that stuff on the MB really needed? This is simply to appreciate, on an intuitive, hobbyist level (I've played with µCs), what goes into a modern PC. Aecho6Ee (talk) 17:16, 2 March 2020 (UTC)[reply]

Aecho6Ee, This might be more suitable for the computing reference desk, but i'll answer never-the-less:

A *modern* CPU needs an insane amount of circuitry to function, which is why the chipset exists. The CPU is incapable of function without that chipset to guide it, and it needs the BIOS to perform setup before it can even do anything useful (as without any setup, the fan is off, and the CPU would be viable to overheat on the spot)

For an old, CPU, however.. Well that's harder to answer, but I'd say go back in time a good bit, to, say, the MC14500B, and look around. —moonythedwarf (Braden N.) 17:36, 2 March 2020 (UTC)[reply]

That's not entirely accurate. There's a wide range, even today. See system on a chip, which would contain most of what you are saying on the CPU chip itself. --OuroborosCobra (talk) 17:58, 2 March 2020 (UTC)[reply]

Well, now we're going to be mincing words: a "CPU" is a different thing than a "chip". The CPU itself is usually a pretty small part of a system-on-chip; and even though everything is very small and fits inside one very nice square-shaped piece of plastic-resin packaging, there are many digital logic circuits other than the CPU inside that little rectangular black box. A few articles might help: electronic packaging; system on chip; multi-chip module; and so on. Nimur (talk) 15:00, 3 March 2020 (UTC)[reply]

If we are going to mince words that way, then what is a CPU? We've been sticking on-die cache for decades. For the last decade, it has not been uncommon for entire GPUs to be on die with the CPU, and we still just call it something like an "Intel Core i5," and not "Core i5 + GPU." Is the math coprocessor part of the CPU? Memory management? --OuroborosCobra (talk) 18:20, 3 March 2020 (UTC)[reply]

OuroborosCobra, I will note that the user asked about PC processors. For SoCs, yes, very little external hardware is needed. —moonythedwarf (Braden N.) 15:02, 3 March 2020 (UTC)[reply]

That's a pretty arbitrary distinction, isn't it? For example, Intel's 10th Generation U-Series gets built into things that look like laptop computers, but the "chipset" is on-package. Meanwhile, you can still buy certain mobile phones that are built using discrete components... If you draw a distinction between "PC"-class and "SoC"-class CPUs, you're not really describing the state-of-the-art or the state-of-the-marketplace. It would be more appropriate to talk about classifying CPUs at different power- or performance- or price- points. Nimur (talk) 16:33, 3 March 2020 (UTC)[reply]

Moonythedwarf, SoCs are used in PCs. There's a section in the SoC article about it. They are common in Chromebooks and smaller laptops, and even some of the Surface line. That's why I brought them up. They aren't just for embedded or specialized applications, but also used in many PCs. --OuroborosCobra (talk) 18:20, 3 March 2020 (UTC)[reply]

OuroborosCobra, Fair point. I always seem to forget about mobile processors. My bad. —moonythedwarf (Braden N.) 20:38, 3 March 2020 (UTC)[reply]

IMO however you spin it, the distinction is going to be arbitrary. Is an Intel Compute Stick, a PC [9]? It may be intended for media centre applications but you can still use it like one even if it's fairly weak hardware. I'm currently typing this with a 46 inch TV as my monitor with a wireless keyboard and mouse. I'm not using an Intel Compute Stick, and frankly given the hardware I wouldn't want to, but I could be. Am I using a PC? Earlier today I was making some changes to a simple PowerShell script I wrote (historically but mostly or completely on this set-up). Last week I was doing a fair bit of Excel work. I couldn't play Red Dead Redemption 2 or probably even Two Point Hospital. But I could likely play the Windows versions of Minecraft Bedrock edition (there doesn't seem to be any hardware requirements unlike with the Java edition although I suspect the Jave edition would still work and definitely older versions should), Stardew Valley or most or all Wadjet Eye Games and I think all Infamous Quests and I think even most Phoenix Online Studios games. So am I using a PC?

If the TV is a distrction, well I also have a 24 inch monitor with HDMI input. They're rarer but not non existent. (And it is and was sold as a monitor. While only Samsung marketing and designers can tell, I'm not sure if the design goal was simply for for Chromecast type devices since they were still relatively new in NZ at the time. I think part of the reason for HDMI is they wanted to have headphone output and DisplayPort was also still only beginning to take over from DVI. To be fair this no longer applies but I'm fairly sure you can still find monitors with HDMI input.)

I think that the Intel STK2MV64CC [10] and is probably better in most respects than the computer I was using 10 years ago which most would call a PC (Opteron 165 mildly overclocked, Nvidia 8500GT 256 MB, I think 4GB RAM but could have been 8GB RAM, HD as storage). The main question mark is the RAM, and storage. (Definitely size, even if you add a 512GB microSD although possibly 1TB will be enough. And although flash, eMMC and SD can be fairly crap although they probably still have better random read and write performance.) See e.g. [11] vs [12] and [13] vs [14] and [15] vs [16] although note that these are intended only for a very quick guide as many of these benchmarks may depends on other hardware, user and when they were done. Especially for the Intel, it's going to depend a lot on the hardware design TDP. Definitely it's better than what I was using 15 years ago. I actually wonder whether in some cases the Compute Stick outperforms my current computer which only has a AMD A10 5800K, although definitely my 32GB RAM and 512GB SSD, and for gaming my 280X means not in most cases.

And the STK2MV64CC is fairly old now. Despite the problems Intel has faced, I think you could design one with Kaby Lake, you'd get something even better although I'm not sure if there's anything beyond Kaby Lake you can use. (I think they haven't bothered to make a new Compute Stick because it didn't have much success.)

Then there's also the famous Raspberry Pis. These can be used for lots of things, but PCs is one common suggestion. Our article even says "The Raspberry Pi Foundation announces that they had sold eight million devices (for all models combined), making it the best-selling UK personal computer, ahead of the Amstrad PCW."

And in case it isn't obvious, I chose these examples because both are relatively small with limited components. Although still very complicated, some Raspberry Pi use a 6 layer PCB [17] and I think most will be like that. Frankly the Pi isn't a great example since they often have GPIO pins and other stuff for the various markets they are in part targeted at which you don't need for a simple PC. But they are also well known and have a fairly open design goal [18] meaning I'm fairly sure you can find a fair bit about the other stuff even if the SoC is still a bit of a black box. The Pis are also passive unlike the tiny fan in the Compute Stick.

As for Nimur's point, I mostly agree with OuroborosCobra. What do you mean mean by 'other components'? This seems to be a Intel Core M7-6Y75 [19]. You can see 2 dies on one side, and a large number of solder balls for the FC-BGA on the other. The 2 die bit is mostly irrelevant. I'm fairly they could make a monolithic one if they tried, it's just not an effective way to make them. (As AMD are showing, maybe even monolithic CPUs are not the best.) Undoubtedly what's on the die is very complicated with a lot of stuff which could be called components.

But although I used CPU earlier, the distinction between which part is the 'CPU' and which part isn't is not that clear cut. I still remember, and I think I may still have in the garage a motherboard with separate L3 cache. I think it may be under 25 years old. Yet many would find it weird to suggest the L3 cache on many modern CPUs is not part of the CPU.

P.S. I chose small size since it's likely to mean minimising components. From a general design standpoint, small sizes does have other tradeoffs. While some have designed Intel based compute sticks without fans [20] it is more difficult. However you can get some fairly fancy passively cooled Next Unit of Computing/mini PC type computers e.g. www.aliexpress.com/item/32766530325.html www.aliexpress.com/item/4000183153450.html . Admittedly I'm not sure how well designed these are or whether they have significant overheating and throttling, but still, they exist. Even with a dinky fan, you're not doing the same thing from a compute stick type design.

Nil Einne (talk) 07:38, 4 March 2020 (UTC)[reply]

Modern CPUs perform bit operations. You need to feed in the values to set the registers. You need a clock pulse to tell the CPU to step through the operations. You can then read what is in the registers. That is the minimal hardware required. You don't need memory. You can set the incoming bits with switches. You don't need BIOS. The CPU runs whatever instruction you set in the registers. You don't need any form of display. You don't even need a CPU fan. If you have a slow clock pulse, it won't heat up. So, you really just need power, a pulse, and some way to feed in some binary numbers and a way to read out some binary numbers. In the end, that is all the CPU does. You set the registers, clock-clock-clock and then read the registers. Modern CPUs do have special connections. You can have direct memory access, bypassing a memory controller. You can have direct video card access, bypassing a bus controller. Of course, you can ignore that stuff and simply not connect it. For example, if you have a fancy CPU with a special direct connection to a high-end video card, but you don't have the video card to connect to, the CPU still works. You just can't play your games with the super high-end graphics. 135.84.167.41 (talk) 12:34, 3 March 2020 (UTC)[reply]

Quite correct. I think, if we're trying to boil this down to a hobbyist/amateur's level of detail, the right way to describe it is that your (main) CPU provides a surprisingly small part of the overall experience of a modern computer. For all the things you expect - like a graphical user interface, multimedia, video, audio, external keyboard, mouse, storage, networking ... and so much more - your main CPU doesn't actually do all of those things. Perhaps it could do those things - hypothetically speaking - but in today's system designs, the main CPU does not actually do any of that stuff by itself. The main CPU needs all the other "stuff." If we were to go over all the stuff, one by one, in sequence, it would literally take thousands of years just to describe it - because modern computers literally contain many billions of parts - for example, see our article on transistor count. It's not practical to list every part: instead, we depend on large numbers of teams - each with their own even-larger numbers of individual engineers - to manage all that "stuff." At the end of it all, we have a hugely complicated machine that does all the stuff that a regular user expects from a computer built in this century. It does a lot more than just "computing" numbers.

And if we want a modern system, we really have no option except to trust the final-result of all the accumulated years effort put in by all of those thousands of individuals, encapsulated inside one or more physical objects that we call the "components" of the whole computer system.

Now, where do e finally put all that "stuff" - all the individual components? Well, that depends on a lot of factors. Digital circuitry can actually be made really incredibly microscopically small - so small that it is absolutely invisible to you. Modern digital circuits can be made so small that the laws of physics tell us that you could not see it using visible light - no matter how powerful your microscope! So why are there still all these separate big bulky square-shaped rectangle things?

In some cases, we can use very large scale integration technology to put every single digital system inside one piece of plastic. But sometimes those super-highly-integrated all-in-one circuits are expensive; sometimes they need big, huge, massive incredibly talented engineering teams to design them; and sometimes even if you put that circuit, it could overheat - and so there are lots of factors that explain why any specific computer is designed to have all those "chips" and other components.

A lot of modern computer system design is a race between keeping up with all the new stuff that people want - and putting all that complexity in one place without breaking anything. You can basically look at the final shape of a computer as some kind of dynamic equilibrium - new stuff gets added, and customers won't buy a computer without it - but collectively, we haven't figured out a way to make that thing fit on to one single tiny little integrated circuit yet. A few years later, we figure that component out - and ... customers have some new thing that they must have, and system designers have to put in another discrete component ...

Nimur (talk) 16:53, 3 March 2020 (UTC)[reply]

Using spontaneous combustion in a power plant

Would artificially induced spontaneous combustion (through rapid oxidation or bacterial fermentation) be a cheaper and less complicated way to generate heat at a power plant, particularly when compared to fossil-fuel and nuclear power plants? The usage of haypiles and compost for that purpose also looks like a better option than non-renewable coal. 212.180.235.46 (talk) 17:50, 2 March 2020 (UTC)[reply]

No. Spontaneous combustion is just an ignition method, once something is already on fire, it doesn't care how it got ignited. Biomass power sources already exist, there's not a whole lot to be gained by creating some exotic ignition method. --Jayron 32 17:52, 2 March 2020 (UTC)[reply]

Fossil fuel power stations also use some kind of ignition method, so this comes down to comparison of ignition methods. To generate heat a fossil fuel power plant uses mainly either a furnace or gas burning, with complex process of coal preparation and ignition to generate steam and ultimately spin the turbines. So, instead of all that machinery why not to use spontaneous combustion that would surely produce the same water steam for spinning turbines and electricity? Brandmeister^talk 20:10, 2 March 2020 (UTC)[reply]

So instead use a more complex, energy intensive, and time consuming process of preparing the coal for the correct conditions for proper and yet predictable spontaneous combustion? I mean, some engine systems rely on it (Diesel engines for example), but I'm not sure that scales for coal power plants. --Jayron 32 12:53, 3 March 2020 (UTC)[reply]

Spontaneous means not artificially induced, but ignition systems for a variety of combustion applications use both the latent heat of a surrounding system, usually as sustained combustion as in jet engines, and timed fuses. EllenCT (talk) 22:44, 2 March 2020 (UTC)[reply]

All that said, it might be viable to utilize the waste heat from already-existing industrial-scale composting (as performed by many local authorities in the UK using municipally-collected collected garden and food waste) either directly or to generate useful amounts of electricity from thermoelectric generators. {The poster formerly known as 87.81.230.195} 90.200.142.153 (talk) —Preceding undated comment added 23:29, 2 March 2020 (UTC)[reply]

Waste heat recovery is an important part of chemical engineering. EllenCT (talk) 00:16, 3 March 2020 (UTC)[reply]

It sounds like a bad idea to me.

Spontaneous combustion of a pile of hay takes some time. Our article says usually 4 to 5 weeks. When you decide to switch on your power station, you want it on the grid within a day.
When there's a good air supply to your compost pile, the air will act as a coolant and prevent ignition. So, you need poor air supply. After ignition the air supply will still be poor, leading to slow burning, a cool flame, dirty smoke and poor efficiency.
What about using it only for ignition? After a few weeks waiting you've got a burning pile of hay, which you then use to ignite your natural gas. Is that really simpler than an electric spark?

Of course you can utilise waste heat. If you have some industrial process that produces waste heat that you can't use otherwise or only need at a lower temperature than your source, it may be a good idea to extract some work from it. The efficiency may be low, but it's better than not using the heat at all (if maintenance of your heat engine isn't too expensive).

Biomass is used to generate electricity, usually by burning it in a way similar to how coal is burned (and usually mixed with coal). It's potentially green energy, but somewhat controversial. The biomass is usually burned together with coal, which is definitely not green, and it's hard to guarantee that the biomass comes from sustainable sources. PiusImpavidus (talk) 10:40, 3 March 2020 (UTC)[reply]

March 4

How much meat do parrots eat in the wild?

Anyone know? Have seen pet Amazon parrots stripping meat and marrow from chicken bones. Judging by the happy trilling noises and eye flaring, they really love it. Supposed to be good for them on an occasional basis.

@@ Line 208: / Line 208: @@
 = March 4 =
+== How much meat do parrots eat in the wild? ==
+Anyone know? Have seen pet Amazon parrots stripping meat and marrow from chicken bones. Judging by the happy trilling noises and eye flaring, they really love it. Supposed to be good for them on an occasional basis.