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January 20

Why do heat index values go below the actual temperature?

In extended heat index tables, the feels-like temperature is below the actual temperature for low humidities, as shown by the dotted line in the graph. Would anyone know why this so?

What is then the base humidity where the feels-like and actual temperatures are equal? Why was this value chosen?

Finally, I can't find a table for zero relative humidity. Is it defined?

Thanks,
cmɢʟee⎆τaʟκ 00:24, 20 January 2020 (UTC)[reply]

Humans perceive high relative humidity to be uncomfortable. That is why high temps and high humidities are associated with a higher-than-actual temp. High temps are mitigated by the cooling effect of evaporation of perspiration. At low relative humidities perspiration evaporates rapidly, leading to increased cooling and the perception of a lower-than-actual temp. Dolphin (t) 00:40, 20 January 2020 (UTC)[reply]

Dew point comfort varies by what you are used to: [1]. So, any type of heat index based on what it feels like is subjective. There are objective measures, like wet bulb temperature, but there's no guarantee that those will match human perception.

Zero humidity shouldn't be possible on the surface of the Earth, although it has gotten close: [2]. You could create a zero humidity environment in a lab, but once you put a human in there to determine how uncomfortable it would be, the water vapor sucked out of them would make it a non-zero humidity again. NonmalignedNations (talk) 04:44, 20 January 2020 (UTC)[reply]

I suppose since it's called feels-"like" temperature, it should compare to a realistic and imaginable dry conditions that people can relate to. Zero humidity doesn't exist, so obviously you can't relate to it. I'd also question how comfortable a totally dry environment would be, especially below 30°C. I really doubt I'd enjoy 25°C at a parching 1% humidity more than 25°C at say 70%. 89.172.58.25 (talk) 06:37, 20 January 2020 (UTC)[reply]

The articles Heat index and Wind chill should be read together. DroneB (talk) 13:53, 20 January 2020 (UTC)[reply]

January 21

According to the logic of racist “geneticists”...

The drift of claims that I get from white, male, racist “geneticists” is that 1.) Europeans are smarter than Africans, on average. 2a.) Women might be smarter than men, on average. 2b.) But even whether or not (2a) is true, because men have more genetic variability, the “geneticists“ claim that there are more male supergeniuses than women supergeniuses..... But, since it is also true that Africans have more generic variability than Europeans, shouldnnt these “geneticists” also admit by the same reasoning that whether or not (1) is true, there would be more African supergeniuses than European supergeniuses? In any case, anecdotal data tends to show, at least to me, that African-Americans of extraordinary ability are more common than they are among European-Americans.Rich (talk) 05:32, 21 January 2020 (UTC)[reply]

You're not likely to be able to dissuade a racist from his views using logic and reason. ←Baseball Bugs ^{What's up, Doc?} carrots→ 06:15, 21 January 2020 (UTC)[reply]

" there would be more African supergeniuses than European supergeniuses?". If variability did really mean that, which is not proven, then there would be also more African/women superdumber so the average would not change, would it? 91.1.100.33 (talk) MPB —Preceding undated comment added 15:14, 26 January 2020 (UTC)[reply]

So, you are claiming that intelligence is absolutely controlled by genetics. I feel that your argument (regardless of which side you are on) is based on a weak assumption. 135.84.167.41 (talk) 17:48, 21 January 2020 (UTC)[reply]

I never made any such claim, and I wouldn’t agree with it. The thing that I bet is most correlated with intelligence (negatively) is lead poisoning. In my post above I had tried and I think succeeded in making it clear that I was referencing racist “geneticist” reasoningand beliefs, not my own.Rich (talk) 22:00, 21 January 2020 (UTC)[reply]

The fatal flaws with statistical generalizations include (1) the assumption that it's possible to determine what "superior" genetics are; and (2) that generalities have nothing to do with individuals. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:10, 21 January 2020 (UTC)[reply]

Yes, if one believes that "intelligence" is a purely genetic trait, then obviously one might , as you say, statistically expect more super geniuses from the varied gene pools in Africa. A few things points against this. Firstly, the notion of "intelligence" itself is poorly defined. Secondly, the connection to genetics is weaker than the connection to other factors, like being born rich. Thirdly, the increased genetic variability in Africa is confined to 14 distinct sub Saharan peoples. I do not know how many people they are, and if there are not many of them, that would affect the statistics. Most African populations, say in Nigeria, are of the same genetic pool as Asian, European and Americans. The greater greater variation comes from 14 distinct peoples. Star Lord - 星爵 (talk) 15:41, 25 January 2020 (UTC)[reply]

Cure for cancer and selective pressure

Given the modern progress in cancer treatment, particularly news about new immune cell, is there a concern that any future cure for cancer (or any other disease for that matter) would provoke selective pressure similar to antibiotic resistance, becoming ultimately ineffective (also given its expected sky-high demand after wider availability)? Would restricted usage mitigate/delay that? 212.180.235.46 (talk) 21:51, 21 January 2020 (UTC)[reply]

Yes, it is a known thing. They already use combination treatments, etc, similar to antibiotics. "Cancer drug resistance" brings a lot of search hits. 67.164.113.165 (talk) 23:08, 21 January 2020 (UTC)[reply]

Except of course that unlike with bacteria, Cancer is not infectious, i.e. a person with cancer cells in their system cannot give another, otherwise healthy person cancer. This means that any resistance developed by cancer cells in subject 1 would be unable to spread or otherwise influence the cancer cells of subject 2. Presumably subjects who are genetically predisposed to be resistant to whatever the miracle cure is for cancer, would expire quicker and would be therefore unable to transfer their genetic code to offspring. Restricted the population it is available to would not impact how quickly an individual becomes resistant to said treatment. Bacterial cells can pass resistance conferring plasmids horizontally to other bacterial cells, vastly speeding up the process of conferred immunity, in comparison to us lowly eukaryotes. — Preceding unsigned comment added by Couldbeanything (talk • contribs) 16:12, 22 January 2020 (UTC)[reply]

Fascinating. Any sources for those claims? ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:36, 22 January 2020 (UTC)[reply]

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2711443/ the only currently known way of transmission is placental — Preceding unsigned comment added by Couldbeanything (talk • contribs) 18:45, 22 January 2020 (UTC)[reply]

January 22

Insomnia and sexual frustration

Is there evidence of a connection between insomnia and sexual frustration? Freeknowledgecreator (talk) 03:50, 22 January 2020 (UTC)[reply]

Certainly. I'm not sure about formal studies, but it would be very easy for the questioner to test the hypothesis at home. Temerarius (talk) 04:28, 22 January 2020 (UTC)[reply]

I wasn't asking for funny or would-be-clever responses. Per "We don't answer (and may remove) questions that require medical diagnosis or legal advice", you should not have responded that way (your comment resembles an attempt to provide diagnosis or advice, which you have no business doing here, and which in any case I was not asking for). I was asking a serious question, looking for a non-wiseacre response. Freeknowledgecreator (talk) 06:53, 22 January 2020 (UTC)[reply]

You get what you pay for. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:34, 22 January 2020 (UTC)[reply]

This is where I would start your research. --Jayron 32 12:59, 22 January 2020 (UTC)[reply]

Potato salad and health

Is potato salad considered a healthy food? Freeknowledgecreator (talk) 06:56, 22 January 2020 (UTC)[reply]

According to Wikipedia, "potato salad is a dish made from boiled potatoes and a variety of other ingredients". Potatoes are widely considered healthy. Beyond that, you would need to identify the other ingredients. The mayo alone could be healthy or not depending on what it's made from.--Shantavira|^{feed me} 09:21, 22 January 2020 (UTC)[reply]

You mean, potatoes are widely considered to be unhealthy. Abductive (reasoning) 10:44, 22 January 2020 (UTC)[reply]

Potatoes on their own are generally a healthy food. What people add to them is always the problem. HiLo48 (talk) 10:51, 22 January 2020 (UTC)[reply]

Getting a balance of nutrients from a wide variety of foods is considered healthy. Getting an excess of a single food is bad. Depending on the preparation and amount of potatoes, as well as the specific variety of potatoes, potatoes vary in their healthiness. It is simplistic to say "eating potatoes is bad" or "eating potatoes is good". Potatoes can be part of a healthy, diverse diet, but could also be eaten to excess, given that they eating them to the exclusion of other foods could lead to an overabundance of some nutrients (like starches and other carbohydrates) and also to missing nutrients that you could be getting from other foods that you aren't because you're eating potatoes instead of those foods.[3], [4]. To answer the OP is not possible in the simple terms. Potato salad could contain any number of ingredients, but given that the bulk of it is potato, a reasonable amount of it as part of a balanced diet would not be the least healthy thing you could eat. --Jayron 32 12:57, 22 January 2020 (UTC)[reply]

This would seem to be the same kind of question as whether coffee is fattening. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:32, 22 January 2020 (UTC)[reply]

Your point being? Freeknowledgecreator (talk) 02:25, 23 January 2020 (UTC)[reply]

That, as with the coffee question, there are too many missing facts in the question. ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:59, 23 January 2020 (UTC)[reply]

How many bones are in a dolphin?

Do any of you know? — Preceding unsigned comment added by 65.51.140.46 (talk) 14:36, 22 January 2020 (UTC)[reply]

All of them. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:30, 22 January 2020 (UTC)[reply]

Googling "number of bones in a dolphin" does not immediately yield an answer, though it would seem to be fewer than the 206 in humans, owing to a lack of real bones in the flukes. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:58, 22 January 2020 (UTC)[reply]

A description and a picture of a dolphin skeleton. DroneB (talk) 19:10, 22 January 2020 (UTC)[reply]

UK rail electrification in passenger-kilometre terms

Hi all,

I hope this is the right reference desk, looking through the archives most related questions have been posted here...

A rather narrow question, as I'm trying to dredge up a figure and can't find it. Possibly I'm just addled from a long day of research across many rail topics lol, but I figured there may be people here with such figures closer to hand than I do.

I'm trying to establish the proportion of passenger-kilometres travelled on the GB rail network powered by electric versus diesel traction. I've seen that only 38 percent of the network is electrified, but in passenger-kilometre or even passenger-journey terms electric rail usage must be far, far higher than that, given that most electrified routes are commuter routes and major intercity routes, but I can't find an exact figure. I feel sure such a figure must exist, or at least a data source from which it can be inferred.

(PS passenger-journey rather than passenger-kilometre terms would be fine, provided the contrast was still sufficient to make the point. I also don't care if the figure is GB or UK, though I strongly suspect the GB figure is more readily obtained.)

Thanks a lot! Dan Hartas (talk) 15:50, 22 January 2020 (UTC)[reply]

Be careful with this, as no-one knows and it's in massive flux. The South Wales main line is supposed to be being electrified (London to Swansea) but chunks of this have been abandoned (beyond Cardiff to Swansea), some just isn't working (Severn Tunnel has water problems), everything around Bath and Bristol was much later than planned, and because the 800 stock has been runing quite happily bi-mode as diesels, the pressure to use it electrically is perhaps less than it would have been otherwise. So in South Wales (AIUI, last time I looked) the power's on, but still not much is running on electric power as yet (short-formation HSTs on local services and 800s with the pantographs down). Andy Dingley (talk) 17:38, 22 January 2020 (UTC)[reply]
- I somewhat doubt 'no-one knows' except perhaps in the form no one has compiled the data yet. I know that UK rail is complicated with a number of different operators. Still, I find it fairly unlikely in this modern age that each operator doesn't have a very good idea of their traction energy share on both a passenger-kilometre and passenger-journey basis. Bi-mode obviously complicates things but it's not like passengers are jumping on and off in random places, or bi-mode trains are like plug-in hybrids in the way they switch so it's hard to keep track. I mean nearly all of them were able to say how much diesel and how much electricity they used [5] and while that just requires raw input which they're paying for; keeping track of how many kilometres your trains are traveling, how many passengers are on them, and what power they were using seems to be the kind of data a company will keep track of not least because it affects maintenance etc. And there is a fair amount of data [6] [7] on the different operators, lines, ticket types etc, unfortunately not this that I could find. Someone was able to come up with figures for 2006-2007 based on data provided by ATOC (I think) [8] (Jstor [9], preprint [10]) which showed 17.9 billion passenger-km for diesel and 28.93 billion passenger-km for electric. And our article Railway electrification in Great Britain has an even older figure of 60% of journeys being by electric traction. (Eurostat has "Train-movements, by type of vehicle and source of power" [11], unfortunately no data for the UK.) Nil Einne (talk) 09:44, 23 January 2020 (UTC)[reply]
  - I found [12] which seems to confirm there's probably no official figure since 2006-2007 "The emission factors were calculated based on the relative passenger km proportions of diesel and electric rail provided by DfT for 2006-2007 (since no newer datasets are available from DfT)". Also I maybe should mention the International Energy Agency has estimates unfortunately only for Europe as a region. [13] / [14] Nil Einne (talk) 09:59, 23 January 2020 (UTC)[reply]
    - Thanks for this! The 2007 figures give a proportion of 61.8% electric then, which I suppose is a lower bound, as there has been some electrification work done since then. Between this [15], which I found this morning, and Andy Dingley's comment, I guess I can establish 75% as an upper bound as well, which is close enough that I can probably make it work. It does seem the sort of thing that there ought to be a figure for, and I have found a few sources that talk like they know this but don't give it. It seems one of those annoying medium-depth pieces of information that is too specific for beginner summaries and too obvious to be included in sources that assume expertise. Obviously if anyone can find it, that would still be welcome, but for now, thanks all! Dan Hartas (talk) 10:06, 23 January 2020 (UTC)[reply]

"No-one knows" means two things here: nothing is published (the rail industry just can't get its act together to commnicate some of this stuff) and secondly really no-one does know what will be happening in a month. Even the operators do not know what power source they'll be using in a month's time on some lines, because work on them is continually being delayed unpredictably.

The main problem isn't the number of operators (they have relatively little overlap), it's the split between Network Rail who have the fixed infrastructure and the group of operators (rollng stock and operation of trains). It doesn't matter what an operator wants to do, and what their trains are capable of, if NR don't have the power turned on over a stretch of it.

We also have some operators who have performed so poorly recently that they're likely to have their franchises either not renewed or even terminated in mid contract. We had this in the past where one was effectively nationalised (and then ran very well). But with today's government as a single-party state aspiring to become a full-blown kleptocracy, those franchises will just be handed out again to some other friends from school, who will be no better. Sadly we've even had European operators operating in the UK and although they did a good job to start with, they've mostly been dragged down to the awful standard of the other operators (inadequate stock, unreliable service and price gouging) because a market where such things are standard will tend to force all operators within it to meet the same low standards.

UK rail is a mess, but then it's no worse than we deserve having voted for it to be so bad. Andy Dingley (talk) 12:15, 23 January 2020 (UTC)[reply]

January 23

Dieting to lose belly fat

What is the best diet to use if you want to get rid of belly fat? Freeknowledgecreator (talk) 00:56, 23 January 2020 (UTC)[reply]

Running 10 kilometres every day. If you do that, you will get a flat tummy, and your body will tell you what to eat. HiLo48 (talk) 01:10, 23 January 2020 (UTC)[reply]

"Running 10 kilometres every day" is exercise, not a diet. I was asking a question about dieting. Freeknowledgecreator (talk) 01:23, 23 January 2020 (UTC)[reply]

The best diet is to exercise.

You're asking for either specific medical advice for one specific person (whom we've not seen, and we can't do medical advice anyway) or else you're asking a very general question. In which case, assuming that your diet is only averagely bad to start with, the best advice is to exercise.

But really, this is a pointless question. We know nothing about either you, or your current diet. Andy Dingley (talk) 01:38, 23 January 2020 (UTC)[reply]

It is a general question. I do not ask for medical or other advice here. Freeknowledgecreator (talk) 01:45, 23 January 2020 (UTC)[reply]

You criticised one sentence of my two sentence response. Clearly the two were meant to be read and comprehended together, and the second (effectively) mentioned diet. It was a serious response, one that worked for me. Very few people lose weight long term without changing their exercise regime. HiLo48 (talk) 01:49, 23 January 2020 (UTC)[reply]

Talk to your doctor. ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:56, 23 January 2020 (UTC)[reply]

One's body fat depends more heavily on their diet than their exercise routine. It's not possible to do away with fat in one specific place on one's body; you can only reduce it overall. Temerarius (talk) 04:48, 23 January 2020 (UTC)[reply]

As everyone says, you can't do it by dieting alone, you need exercise too. Selectively modifying the shape of your body through a combination of diet and exercise is the sport of bodybuilding. Assuming you're not talking about a level of obesity that calls for medical attention, you can get individualized help by going to a gym and working with a personal trainer. The basic exercise for dealing with belly fat is the abdominal crunch. 2601:648:8202:96B0:0:0:0:4FFF (talk) 00:50, 24 January 2020 (UTC)[reply]

This is a common misconception. Your body does not burn the fat deposits that happen to be nearer to the muscles getting exercised. It burns fat from all over, evenly. Abductive (reasoning) 02:25, 25 January 2020 (UTC)[reply]

True, but abdominal crunches will give the best muscle development in that area. To burn fat, you need whatever sort of aerobic exercise you enjoy enough to keep doing it. I like cycling as it's otherwise pretty low impact, some prefer swimming for much the same reason, people with functional knees might try running. Andy Dingley (talk) 01:32, 26 January 2020 (UTC)[reply]

There is no evidence that crunches are anything but dangerous. Abductive (reasoning) 01:45, 26 January 2020 (UTC)[reply]

Coronavirus mortality rate

Have just read that the Coronavirus now has a 3.6% mortality rate (17 deaths) so far, is that unusually high for infectious disease? Ecolchester (talk) 04:16, 23 January 2020 (UTC)[reply]

Data on the number infected is likely a little less reliable than data on the number killed. I'm not suggesting a cover-up saying that, either. When dealing with a newly discovered illness, we are going to have early patients that were treated without realizing this was the infection, for example. As for mortality rate being high, that really depends on the infection. The average mortality rate from ebola is about 50%, and ranges from 25% to 90% depending on the outbreak strain. The 2009 Swine Flu had a mortality rate potentially as high as 0.08%, but probably lower (that's calculated based on the lowest estimated number infected and the highest estimated number killed). Another variation of the flu, the H5N1 bird flu, has an estimated mortality rate of about 60%. SARS had an estimated mortality rate of about 15%. These also differ greatly among different effected groups and age ranges. In SARS, for example, those under 24 years old had a mortality rate of about 1%, 6% for those 25 to 44 years old, 15% for those 45 to 64 years old, and a whopping 50% for those 65 years old or older. --OuroborosCobra (talk) 16:28, 23 January 2020 (UTC)[reply]

A good overview. It's an interesting side note that the so-called Spanish flu had a different mortality age graph than you'd normally expect from a respiratory disease (including this new one, where the deaths are mostly older males with previous health issues, as is the usual case with flus). This is detailed here and should serve as a reminder that questions about expected mortality are always subject to harsh realities. At this early stage, claims for whether this new strain will be more or less lethal than SARS are up in the air. Here is a pessemistic one from the Toronto Globe & Mail and here is a more measured one from the CBC. Matt Deres (talk) 18:55, 23 January 2020 (UTC)[reply]

Vegetarianism and weight loss

Does a vegetarian diet help a person to lose weight? Freeknowledgecreator (talk) 05:55, 23 January 2020 (UTC)[reply]

Not automatically. The first vegetarian I knew well was a somewhat plump lady who ate an awful lot of nuts. HiLo48 (talk) 06:08, 23 January 2020 (UTC)[reply]

All right, let me revise the question - what sort of a vegetarian diet would be suitable for a person who wants to loose weight? Freeknowledgecreator (talk) 06:13, 23 January 2020 (UTC)[reply]

A diet is often used to lose weight by eating differently. Since the habits that cause the excess weight don't change the weight loss is only temporary, lasting while the diet lasts. As mentioned in the previous section on food, changing these habits (e.g. more exercise, less fast food) is more effective for changing your weight.

What you are asking for is difficult to answer since we aren't dieticians and we don't know your situation. One thing that would work in general is eating the same ingredients/meals as you eat now but reduce the amount (assuming your food is otherwise normal, that should be safe). Vegetarian cuisine would be a good place to start for background info and you could check the internet for some cookbooks (e.g. this list). Rmvandijk (talk) 07:52, 23 January 2020 (UTC)[reply]

You should be asking your doctors these questions. ←Baseball Bugs ^{What's up, Doc?} carrots→ 08:40, 23 January 2020 (UTC)[reply]

Depends how many vegetarians you eat. I've been a vegetarian for decades. Generally healthy, but I'm overweight and my cholesterol is higher than I'd like, because of cheese (there's just nothing else I eat which would do this). Also because I ignored the advice given to your previous thread and I don't get enough exercise.

I do not "know many skinny vegetarians". If anything, they're all pretty hefty. Skinny vegans aplenty though. The factors controlling all that are clearly more social than simply dietary.

Is a vegetarian diet a good idea? Of course! (but I would say that, wouldn't I) Advantages all round, for you and the planet (and the cows). But it's not a panacea for everything, and there are still good and bad aspects possible within it.

Really, no-one here can help you in detail, because we've no idea who you are and what your particular issues are. But you probably know them yourself, so yes, you're going to have to address them. Diet of processed food and take-aways? Stop ordering and cook more. No exercise? Do exercise. Simply too much of a good thing? Eat less of a good thing. Andy Dingley (talk) 12:04, 23 January 2020 (UTC)[reply]

To be perfectly clear about it, I am not asking for medical advice or help specifically in relation to my health. I am aware that such questions are inappropriate. I am asking general questions only. Freeknowledgecreator (talk) 19:27, 23 January 2020 (UTC)[reply]

In which case, it all depends on how much of that vegetarian diet you eat, in relation to the amount you exercise. Although having some clear health benefits (mostly from the reduction in some types of meats, a diet which includes fish or some low-fat white meats would have nearly as much benefit), vegetarianism is no guarantee of weight loss by itself. Quantity still matters. Andy Dingley (talk) 23:37, 23 January 2020 (UTC)[reply]

Losing weight by dieting comes down to caloric restriction. A vegetarian diet doesn't seem likely to help with that. It will tend to have less concentrated energy sources than meat-containing diets, so you end up eating more often unless you're careful. I know plenty of overweight vegetarians. I realize your questions aren't medical but I think refdesk isn't in a good position to advise you, since everyone's requirements will be quite individualized. If you're seriously obese, talk to a medical person; otherwise, see a nutritionist. I do know people who have lost considerable amounts of weight and their basic strategies were similar: 1) eat small portions; 2) deal with between-meal hunger by snacking on low-calorie stuff like carrot sticks or celery; 3) avoid sugary drinks, fruit juices, or large amounts of fruit, since those are all full of sugar that has ridiculous amounts of calories. People often overlook that last one. 2601:648:8202:96B0:0:0:0:4FFF (talk) 07:36, 24 January 2020 (UTC)[reply]

January 24

How healthy are fruit juices?

How healthy are commercially available fruit juices, especially orange juice? Are they fattening? Freeknowledgecreator (talk) 09:08, 24 January 2020 (UTC)[reply]

Are you writing a book on nutrition, one question at a time? ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:09, 24 January 2020 (UTC)[reply]

No as a matter of fact I am not. Once again I am asking a serious question, looking for a serious answer. It is a general question, not a question about my personal health. Freeknowledgecreator (talk) 09:10, 24 January 2020 (UTC)[reply]

That's not what I asked. ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:21, 24 January 2020 (UTC)[reply]

OK. I'm not interested in some kind of confused argument/head-butting thing. I am asking a serious question about how healthy fruit juices are. Someone please answer it. Freeknowledgecreator (talk) 09:23, 24 January 2020 (UTC)[reply]

They are less healthy than people think. They're loaded with sugar, and you don't get any of the nutritional benefits of actually eating the fruit, such as digesting fiber. Really though, you are in the wrong place. Better to read some books on these topics. As for fattening, yes, go by the calorie content. 2601:648:8202:96B0:0:0:0:4FFF (talk) 11:22, 24 January 2020 (UTC)[reply]

I subscribe to this view: eating fruits is healthy, the main reason is because fruits are low-calories. Fruit juices aren't fruits. Orange juice has the same amount of sugar as Coca Cola. Tgeorgescu (talk) 12:11, 24 January 2020 (UTC)[reply]

Coca-Cola Zero Sugar has no sugar. Freeknowledgecreator (talk) 06:39, 26 January 2020 (UTC)[reply]

There's a free internet based service called "Google" that you can use to research the answers to these questions. Your questions are of the type and format that if you type them into the search bar at this service, you get results that are more useful than asking here and waiting around for someone to give you an answer. For just one example, I used your question title here "How healthy are fruit juices? and got a plethora of reliable sources you could use to answer your own questions, and on a time frame which is much faster than waiting for someone here to do it. On the very first page of that search, I found this article from the BBC which itself cites and links to numerous studies and reliable sources which can answer your question. --Jayron 32 12:16, 24 January 2020 (UTC)[reply]

Healthy in what way? There is one big question these days, especially in the US, on health issues around the widespread use of high fructose corn syrup(HFCS). Now fruit juice might avoid that, or it might be a faked "fruit" juice made from HFCS dyed orange. Fruit juice itself contains fructose, and there are concerns over that too (if you're going to eat sugar, don't eat fructose as that sugar).

Then the issue of the sugars in fruit juice. If you're in the West, easy over-abundance of sugars is perhaps our worst dietary problem - even more so than fats. So why drink something like this which is so heavy in them? Historically, fruit juice was seen as "healthy" in the mid 20th century, because it was scarce and it was a source of vitamin C (unless you have a terrible diet, or you're an ancient mariner, you're unlikely to be short on vitamin C). This led to decades of misunderstanding since, still buoyed up by marketing, that "fruit juice is healthy" when in fact it isn't. At the most, it might be better than non-fruit-based, high sugar or carbonated drinks.

Then there's dentistry. Fruit juice is terrible there. Sugary and acidic. The only things worse are carbonated drinks (even soda water is bad for your teeth, just because carbonation makes it acidic). If you do drink fruit juice, don't drink it before bedtime and don't (don't!) clean your teeth for an hour after drinking it (i.e. if you need to clean your teeth, don't drink fruit juice beforehand). Andy Dingley (talk) 12:59, 24 January 2020 (UTC)[reply]

The advice of the UK National Health Service is to "limit the amount of fruit juice, vegetable juice or smoothie you have to no more than a combined total of 150ml a day (1 small glass)", but that this can count as one of your 5 A Day, so it's not all bad. [16] Alansplodge (talk) 17:56, 24 January 2020 (UTC)[reply]

After Man Continental Drift.

A 5-second animation showing 250 million years of continental drift. Geologist author Dougal Dixon's speculations in "After Man" would occupy a further second. DroneB (talk) 23:49, 24 January 2020 (UTC)[reply]

The book, After Man is set 50 million years in the future. Five of the most significant moves of the Continents by the time of the book are as follows.

Africa has completely collided with Europe and raised mountains where the Mediterranean is
East Africa has split completely off of Africa
Australia has run into the East Indies and pushed them north and raised significant mountains
North America and Asia are now connected (closing of the Bering Straight) without significant change apparent change in sea level (supposedly due to the widening of the Atlantic)
South and Central America are no longer connected.

The first three seem expected from what I've seen on continental drift. I'm unsure whether the last two would be expected with current science in the field.Naraht (talk) 18:09, 24 January 2020 (UTC)[reply]

Our article Future of Earth has a little bit on this and some useful citations. Chris Scotese in his PaleoMap Project provides a map at 50 million years in the future. In that construction, this first and third point are predicted but the second one isn't. As to the fourth point, he shows that Baja California has slipped all the way up to Alaska - note that North America and northeastern Asia are actually on the same plate - the Bering Strait is not a plate boundary. In this construction, North and South America remain connected - they are currently slowly converging, so the fifth prediction seems unlikely on that basis. Mikenorton (talk) 17:08, 25 January 2020 (UTC)[reply]

You can read some more of the detail here. The breaking up along the East African Rift appears to be stopped by the continuing collision between the Arabian Plate and the Eurasian Plate causing the closing of the Red Sea and the Gulf of Aden. Mikenorton (talk) 17:27, 25 January 2020 (UTC)[reply]

January 25

hazard classification of hexafluorosilicic acid

I recently saw this image: file:NFPA 704 label of hydrofluosilicic acid.jpg which describes a chemical with a health hazard level of '1', no flammability hazard, a reactivity level of '1', and a special note that it is corrosive. The chemical is labelled 'hydrofluosilicic acid', which as far as I can tell from casual web searching is the same as hexafluorosilicic acid (modulo hydrated/anhydrous preparations); however, that article does not give a hazard description of 1-0-1-COR, but rather 3-0-0-COR. Either I falsely conflated two different chemicals, or one or the other source for the hazards is incorrect (I'd tend to believe the article's sources over the sign creators), or I suppose some other explanation I have not anticipated. Which is it? Arlo James Barnes 00:45, 25 January 2020 (UTC)[reply]

Each manufacturer arrives at their own numbers, so they don't have to match.

Abductive (reasoning) 02:22, 25 January 2020 (UTC)[reply]

I see, thank you. I must admit that I only now read the NFPA 704 article (instead relying on my memory of a hazcom crash course I took, which is a mistake as my memory is patently unreliable), which does not discuss how manufacturers arrive at the numbers* or if there are consequences for them publishing wildly incorrect numbers. Perhaps it should? I note that talk:NFPA 704 is full of these sorts of discrepancies, and wonder if this poses a sourcing challenge for Wikipedia. Are there no canonical testing laboratories? (*Well, the descriptions of the hazard categories imply that they might expose them to rising heat or shock, and presumably reference case literature for the other quadrants?)

Arlo James Barnes 06:34, 25 January 2020 (UTC)[reply]

I have changed to GHS for the hazards info for the article. Note that the LD-50 for rats is 430 mg/kg. This is not actually very low, and for example sodium fluoride is about 10 times more toxic (Rats oral 32.0 mg/kg). Common salt is about 7 times less toxic (LD50 Rat oral 3000 mg/kg). So it may not he as hazardous as we think it should be. Though here:[17] it supports the health rating of 3. Note that the product sold will be a water solution. Graeme Bartlett (talk) 11:32, 25 January 2020 (UTC)[reply]

People with influenza drinking tea

If a person contracts influenza, is it considered safe or medically desirable for him or her to drink tea? Freeknowledgecreator (talk) 07:40, 25 January 2020 (UTC)[reply]

Why not? Ruslik_Zero 08:38, 25 January 2020 (UTC)[reply]

I'm looking for serious answers only. Freeknowledgecreator (talk) 09:14, 25 January 2020 (UTC)[reply]

Why not? Andy Dingley (talk) 11:12, 25 January 2020 (UTC)[reply]

[18] only prescribes water. Bazza (talk) 11:50, 25 January 2020 (UTC)[reply]

The doctors will always say water, because it is the safest option. However I have never heard that tea is contraindicated in case of influenza. Ruslik_Zero 15:03, 25 January 2020 (UTC)[reply]

I wouldn't go as far to say it's contraindicated but some sources recommend against it because of the caffeine [19], either over concerns of the Diuretic effect [20] [21] or the stimulant effect on body temperatures [22] That said, since any effect it relatively small [23] and drinking tea (or even coffee, energy and colas) will rehydrate [24] provided you don't limit your fluid intakes, I don't think this advice is particularly strong. (It may be stronger for the other beverages for other reasons.) Especially in a case where a person's fluid intakes are too low on water but they are will consume adequate amounts if given tea, I doubt anyone who isn't crazy is going to recommend against it. And to be clear, such concerns don't arise with decaffeinated teas, or herbal teas without significant caffeine. Note that as with everything, you should ensure you don't go overboard with your fluid intake anyway [25] [26] (neither of these were about influenza but the general idea that you can take things too far almost definitely still applies). Also as the first source says, if your dehydration is severe enough, it needs to be treated with the assistance of medical personnel, not at home. Nil Einne (talk) 03:26, 26 January 2020 (UTC)[reply]

If tea doesn't help, there is always gin.[27] 2601:648:8202:96B0:0:0:0:4FFF (talk) 02:07, 26 January 2020 (UTC)[reply]

Is it safe? Yes. Is it medically desirable? Yes, it is important to maintain a high level of hydration. Is it medically desirable to drink nothing but tea? No, there is nothing medically beneficial about the flavouring we call tea. A little vitamin C each day will be beneficial. Dolphin (t) 03:03, 26 January 2020 (UTC)[reply]

Please do not forget that legal or medical advice is prohibited at the Wikipedia reference desk. --Lambiam 03:55, 26 January 2020 (UTC)[reply]

To be perfectly clear about it, I was not and am not asking for legal or medical advice. Freeknowledgecreator (talk) 05:42, 26 January 2020 (UTC)[reply]

The claim about vitamin C appares to be medical advice, though, and dubious at that. --142.112.159.101 (talk) 07:54, 26 January 2020 (UTC)[reply]

January 26

gallbladder removal

[28]"His gallbladder had been removed, an unnecessary operation that caused permanent complications."

What kind of complications result from this? Postcholecystectomy syndrome? I had thought this operation was pretty routine. I know some people who had it (years ago) and did fine. Thanks. 2601:648:8202:96B0:0:0:0:4FFF (talk) 02:01, 26 January 2020 (UTC)[reply]

As well as postcholecystectomy syndrome "Complications of cholecystectomy include bile duct injury, wound infection, bleeding, retained gallstones, abscess formation and stenosis (narrowing) of the bile duct" This is covered in more detail in our article on cholecystectomy.--Shantavira|^{feed me} 09:31, 26 January 2020 (UTC)[reply]

Health effects of drinking human blood

If a person were to drink human blood, would that be fattening? Freeknowledgecreator (talk) 06:33, 26 January 2020 (UTC)[reply]

At this point I am getting a thirst for drinking troll blood. 67.164.113.165 (talk) 09:34, 26 January 2020 (UTC)[reply]

It is a serious, matter of fact question. I am looking for a serious, matter of fact answer. If you find a question offensive for some reason, you obviously do not have to respond to it. Indeed, it is probably better to make no response in such situations. Freeknowledgecreator (talk) 09:40, 26 January 2020 (UTC)[reply]

Please try google before asking further stupid questions here. Example. 67.164.113.165 (talk) 09:51, 26 January 2020 (UTC)[reply]

Insulting me really serves no purpose. If you don't like the question, don't respond. That should be simple enough, shouldn't it? As for those Google hits, none of them, at a quick look, address the specific question of whether drinking human blood would be fattening. Freeknowledgecreator (talk) 09:54, 26 January 2020 (UTC)[reply]

See Black pudding#Nutrition. Not about drinking it, but eating it. Seems like it depends on the recipe. HiLo48 (talk) 10:05, 26 January 2020 (UTC)[reply]

You Australians have some crazy black pudding recipes. Most other places use pork blood for their black pudding although some may use sheep or cow blood. Various other blood sausages exist but human blood sausages is a new one to me. (Discounting vampire fiction.) Nil Einne (talk) 10:41, 26 January 2020 (UTC)[reply]

Are we sure Mrs. Lovett never made sausages instead of pies? HiLo48 (talk) 10:50, 26 January 2020 (UTC)[reply]

As I have previously responded the level to which any food is fattening depends on how much you consume compared with the amount of effort used to burn the consumed calories (this is only part ot the complex problem of obesity) See Blood as food. Where would you propose to obtain the human blood, or is this a hypothetical question? Richard Avery (talk) 15:36, 26 January 2020 (UTC)[reply]

The question is, of course, entirely hypothetical. Freeknowledgecreator (talk) 23:30, 26 January 2020 (UTC)[reply]

(Singing) Use HiLo48, if you must watch your weight! Gråbergs Gråa Sång (talk) 17:08, 26 January 2020 (UTC)[reply]

(e/c) These questions are pointless, not because any one of them are "stupid" but because you don't seem to be getting the gist of the answer: NOTHING in and of itself can just be called fattening or healthful or thinning or good for reducing belly fat or any of the other tiresome variations you've raised. The dose makes the poison and no one eating event is going to change your body's fat content appreciably. You need to consider the entire diet, the body of the consumer, their level of exercise, their general fitness and metabolism, and other things. Matt Deres (talk) 15:45, 26 January 2020 (UTC)[reply]

You have a point, but it still serves some purpose to ask whether a given food or substance would be fattening. If necessary, interpret the question, "is x fattening?" to mean, "If a person consumes x on a regular basis, would that be fattening?" Freeknowledgecreator (talk) 23:04, 26 January 2020 (UTC)[reply]

What would be an average serving size? Bus stop (talk) 23:52, 26 January 2020 (UTC)[reply]

Irrelevant. I am simply noting that even if there is no food or substance that is automatically fattening in every situation, it is still legitimate to speak of a given food or substance as having a tendency to be fattening, hence the point of the questions I've been asking. Freeknowledgecreator (talk) 00:13, 27 January 2020 (UTC)[reply]

That's a valid point. My guess would be human blood would be similar to blood of some of the other creatures we eat. One exception might be Horseshoe crabs, which use Hemocyanin to carry oxygen instead of Hemoglobin, as used by humans. Would this be cooked or uncooked human blood? We also have to be concerned with blood-borne disease—"Since it is difficult to determine what pathogens any given sample of blood contains, and some bloodborne diseases are lethal, standard medical practice regards all blood (and any body fluid) as potentially infectious." Bus stop (talk) 00:22, 27 January 2020 (UTC)[reply]

You appear to be obsessed with this general subject. ←Baseball Bugs ^{What's up, Doc?} carrots→ 08:12, 27 January 2020 (UTC)[reply]

January 27

Bransden and Joachain, Introduction to QM

Does anyone know this book? Do you recommend it as an introductory QM text for someone with a reasonable math background but not much physics beyond elementary mechanics? Thanks. 173.228.123.190 (talk) 09:46, 27 January 2020 (UTC)[reply]

Oxford Electric Bell

How is the Oxford Electric Bell not a perpetual motion machine? Thanks. Anton 81.131.40.58 (talk) 11:29, 27 January 2020 (UTC)[reply]