Wikipedia:Reference desk/Archives/Science/2015 June 20

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June 20

Ambulances in japan

Can ambulances in Japan provide advanced life support? I heard years ago they could only provide basic life support due to resistance from doctors? Is this still the case? 2001:268:D005:E2EF:3D19:3D93:82D0:6AA5 (talk) 04:36, 20 June 2015 (UTC)

See Japan’s paramedics in a straitjacket from 2006 and the more detailed Trauma Systems in Japan: History, Present Status and Future Perspectives from 2005. I couldn't see anything more recent. Alansplodge (talk) 18:34, 20 June 2015 (UTC)

Which of these foods are Probiotics?

Ok, I'm this is a serious question and would be happy to have it answered by some knowledgeable folks on here.

Which of these short list of foods are considered specifically "probiotics". I guess it would be most helpful if you could classify each food as either: 1: An excellent probiotic food, 2: Somewhat okay source for probiotics, or 3: Not at all a probiotic food.

• Eggs
• Margarine
• Peanut-butter
• Cream cheese
• Soy
• Ramen soup
• Rice
• Lentils
• Ensure liquid nutritional supplement (that specific brand)

I don't know if a raw/cooked state for some would make a significant difference in the amount of probiotics but if so that would also be helpful to know, thanks very much. 184.65.230.52 (talk) 06:08, 20 June 2015 (UTC)

None. Probiotics are microorganisms such as certain bacteria that normally live in a healthy person's intestines. Some foods, such as live culture yoghurt may contain such organisms, but a foodstuff is not a probiotic itself. Roger (Dodger67) (talk) 06:26, 20 June 2015 (UTC)

From our article: "Scientific evidence to date has been insufficient to substantiate any anti-disease claims or health benefits from consuming probiotics". AndyTheGrump (talk) 06:27, 20 June 2015 (UTC)

Outside the context of that article, however, it's worth qualifying that statement to point out that some of the same organisms that feature in probiotics are utilized in some medical treatments. It's just that these treatments do not involve consuming them; instead, intermediary measures are made to promote the development of the healthy microbiota that normally inhabit the gut. But in any event, I agree with the response below that from the looks of the list, it is quite possible the OP has conflated "macrobiotic" with "probiotic". Snow ^{let's rap} 21:59, 20 June 2015 (UTC)

Googling "what foods are probiotics found in" yields a lot of results, so you could start there. ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:15, 20 June 2015 (UTC)

• See also, fecal transplant. μηδείς (talk) 21:34, 20 June 2015 (UTC)

• I suspect the OP may actually be interested in a macrobiotic diet: "Japanese macrobiotics emphasizes locally grown whole grain cereals, pulses (legumes), vegetables, seaweed, fermented soy products and fruit..."

Biological effects of Radon-222 exposure at 100% concentration

A rather morbid hypothetical question concerning the Radon article's concentration scale: If one managed to inhale pure ²²²Rn (an environmentally-impossible situation, I know), just how quickly would one be "pushing up the daisies" as a result? In other words, what would be the immediate biological effects of exposure at 5.54*10¹⁹ Bq/m³? I assume that asphyxiation would be a comparatively minor concern, considering. DWIII (talk) 07:59, 20 June 2015 (UTC)

I would think it would be about as soon as if you were deprived of oxygen by any other means - not long. Inert gas asphyxiation suggests you'd be out cold within about a minute and brain-dead within about 7 minutes. ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:16, 20 June 2015 (UTC)

It's spelt radon.
Sleigh (talk) 09:40, 20 June 2015 (UTC)

My eyes are not the best. Where is it misspelled here? ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:51, 20 June 2015 (UTC)

I think Sleigh is objecting to the capital R. Tevildo (talk) 10:25, 20 June 2015 (UTC)

Then he should change the article, whose title currently is "Radon". ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:17, 20 June 2015 (UTC)

No, just change the link to radon. Dbfirs 07:39, 21 June 2015 (UTC)

If Sleigh is that concerned, he could change it himself. ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:02, 22 June 2015 (UTC)

Asphyxia would get you first - see Acute radiation syndrome and Orders of magnitude (radiation). Harry K. Daghlian received about 500 rads and died in 25 days. Louis Slotin received about 300 rads and died in nine days. An operator at United Nuclear Fuels received about 10000 rads and died in 49 hours (this paper, page 34). But, as Bugs has mentioned, lack of oxygen would kill you in a few minutes. Tevildo (talk) 10:10, 20 June 2015 (UTC)

I suppose then we could assume an 80-20 mix (by volume) of radon and oxygen to mitigate against oxygen-deprivation. Given that, we are talking about a radon concentration trillions of times as much as could be found in nature (i.e., build-up in uranium mines). For an 80 kg human and a decay energy of 5.6 MeV per atom, I'm coming up with an estimated 50,000,000 rads per second(!) (quick calculation; I could be wrong). DWIII (talk) 10:36, 20 June 2015 (UTC)

Correction: That calculation is assuming direct contact with an entire cubic meter. Normal breathing (at half a liter per 2 seconds, say) still implies approximately 10,000 rads per second within one's lungs. DWIII (talk) 10:47, 20 June 2015 (UTC)

You can't calculate like that. Rn-222 is almost pure alpha, with only a single gamma emission at 0.51 MeV with a yield of 7.6e-4 (ICRP-07). As for the original question, I'd say the burns would get you first, since for 9.73 kg (1 m³ at standard temperature and pressure) of Rn-222 we're dealing with ~50 MW of decay heat... :-) Kolbasz (talk) 11:41, 20 June 2015 (UTC)

Spot reduction with topical substance

According to the article linked above, local spot reduction (trying to reduce your belly targeting it with specific exercises) is not possible or barely significant, at best.

However, is it possible to reduce a concrete spot with topical gels, creams or lotions? There are many products which claim to reduce fat selectively. Couldn't a substance exist that sends the signal to adipose cells to get rid of fat?--Yppieyei (talk) 14:58, 20 June 2015 (UTC)

Theoretically possible, but it doesn't exist, as far as I know. How would it work, exactly ? Cause the fat cells to die ? Cause them to leak out fat ? Cause them to convert fat into something else ? StuRat (talk) 23:01, 20 June 2015 (UTC)

Density of Graviton?

Hi,
Let intensity of a gravitational field be the amount of gravitational force that a mass creates.
Is there any correlations between Gravitons' density in specific place and the intensity of a gravitational field?
Exx8 (talk) — Preceding undated comment added 15:21, 20 June 2015 (UTC)

The "density" here meaning the number of theoretical gravitons in a given volume ? StuRat (talk) 23:06, 20 June 2015 (UTC)

Someone else here who better understands the subject should arrive to address this question shortly, but in the meantime I will direct you to our Static forces and virtual-particle exchange article for some background on the subject. -- ToE 00:36, 21 June 2015 (UTC)

Perhaps as a lead-in to the graviton question, we can see if there is any similar question which can be properly asked regarding the density (of some sort) of virtual photons mediating a particular electrostatic field. At Stack Exchange, What is the density of virtual photons around a unit charge? received the answer that the density would be infinite due to infrared divergence (which, unlike ultraviolet divergence, does not require renormalization to save the day since measurable quantities remain finite due to the falling energies at longer wavelengths). The reformulated What is the spectral energy density of virtual photons around a unit charge at rest? appears to have been blown off with the equivalent of you can't count virtual particles because they're not real, you silly goose! and a link to Virtual Particles: What are they?. (Our article: Virtual particle.) I'm still trying to digest it all, and hope that one of our subject matter experts will make a timely appearance.

If we can answer (or even figure out how to ask) the parallel electrostatic question, then perhaps we can see what can be answered about the more hypothetical graviton. -- ToE 13:09, 21 June 2015 (UTC)

For real photons or gravitons, i.e., electromagnetic/gravitational waves, the number of particles is proportional to the energy of the wave. For virtual particles, i.e., the fields of objects, it's not clear that there's any way to count the particles, as ToE said. Still, I think it's fair to answer yes to the question, because basically the field energy is proportional to the particle count.

But if a wave (or other field configuration) is spread out over space, then the particles are spread out too. They aren't pieces of the wave like sand grains are pieces of a dune. So talking about the density of particles in some smaller region of space may not make sense. -- BenRG (talk) 18:18, 21 June 2015 (UTC)

Need an introductory and generalist engineering book

One that I found is kind of too basic (Engineering Fundamentals: An Introduction to Engineering - Saeed Moaveni ). Others are specialized in one particular discipline. Which would be an Engineering 101 text book? --YX-1000A (talk) 22:36, 20 June 2015 (UTC)

I don't know of one. The only useful engineering book i ever read that wasn't a text was Structures by JE Gordon. Greglocock (talk) 02:56, 21 June 2015 (UTC)

Some of the books that prepare for U.S. Professional Engineering license are pretty good especially for practical understanding use. General engineering across multiple disciplines used to be in the Engineer In Training national exam (Engineers pass two exams along with requisite professional work). I learned more about different engineering fields from the exam prep than school as the topics covered in the exam were not all required in University. NCEES is the parent and controlling organization that sets standards and the books that help are related to those exams. Note that they are broad and practical but lack detail often necessary to meet engineering practice standards that only come from experience. It will demonstrate, for example the engineering and physics of a turbine engine but it's not going to make you competent enough to be a turbine engine design engineer. --DHeyward (talk) 07:02, 21 June 2015 (UTC)

Something like that is exactly that I was searching for. It is clear that it will be necessarily just an overview for the whole field, and not a way of solving real-life engineering problems.--YX-1000A (talk) 13:29, 21 June 2015 (UTC)