Wikipedia:Reference desk/Archives/Science/2016 December 27

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December 27

Distance to stars

I was surprised to learn that the distance to stars is not known very accurately. For instance, the distance given for Betelgeuse is +/- 22%. That seems like quite a bit of uncertainty for something so close. Is it errors in measuring the parallax? Bubba73 ^{You talkin' to me?} 05:29, 27 December 2016 (UTC)

The problem is that except for either very close stars, where the parallax can be well-measured, or for certain types of stars like Cepheid variables with unusually uniform brightness characteristics, we have to guess based on an unsure distance and an unsure luminosity. When measuring parallax, we've got at best 15 or so light minutes as a baseline to guess an angle where the other legs of the triangle may be hundreds of light years or more. Betelgeuse's luminosity is highly variable, and its size is also uncertain as the article will explain, so it's a tough case. μηδείς (talk) 05:47, 27 December 2016 (UTC)

Cosmic distance ladder explains how the distances of astronomical objects are determined. The pre-Gaia parallax of something that far is crap. That spacecraft will greatly increase the distance of 1% error, 10% error etc. and measure parallaxes a large fraction of the way across the galaxy except Betelgeuse is far too bright to be measured I think. Sagittarian Milky Way (talk) 06:02, 27 December 2016 (UTC)

That helps a lot. Bubba73 ^{You talkin' to me?} 06:37, 27 December 2016 (UTC)

Resolved

• What does "too bright to be measured" mean? —Tamfang (talk) 01:43, 30 December 2016 (UTC)

The Gaia spacecraft is extremely sensitive and was designed do astrometry on magnitude 20 to 5.7 stars. It's predecessor, Hipparcos, was only designed for magnitude 13 but could measure the brightest star in the sky (magnitude -1.4). But I didn't know this was added to the article: "tests carried out during the commissioning phase indicated that Gaia could autonomously identify stars as bright as magnitude 3. When Gaia entered regular scientific operations in July 2014, it was configured to routinely process stars in the magnitude range 3 – 20. Beyond that limit, special procedures are used to download raw scanning data for the remaining 230 stars brighter than magnitude 3; methods to reduce and analyse these data are being developed; and it is expected that there will be "complete sky coverage at the bright end" with standard errors of "a few dozen µas"." (worse than the normal 6.7 microarcseconds still but better than Hipparcos' hundreds). So Betelgeuse is probably not too bright to be measured after all. Sagittarian Milky Way (talk) 04:19, 30 December 2016 (UTC)

Lithium-ion batteries in smartphones emit more than 100 toxic gases

I have experienced this

http://www.ibtimes.co.uk/lithium-ion-batteries-smartphones-emit-more-100-toxic-gases-say-researchers-1587570

Which smartphones don't emit such toxic gases? 42.110.158.213 (talk) 11:16, 27 December 2016 (UTC)

" the gases emitted when a range of commercial lithium-ion batteries are heated to the point of combustion. "

So don't set fire to your phone battery.

Jie Sun; Jigang Li; Tian Zhou; Kai Yang; Shouping Wei; Na Tang; Nannan Dang; Hong Li; Xinping Qiu; Liquan Chen (2016). "Toxicity, a serious concern of thermal runaway from commercial Li-ion battery". Nano Energy. 27. doi:10.1016/j.nanoen.2016.06.031. Andy Dingley (talk) 11:39, 27 December 2016 (UTC)

• None.

Rant time. That question, which merely reflects the general tone of the article (which itself is the most exaggerated yet true version that the quoted scientists could approve, following the recipe of [1]), is loaded.

Any material of any kind that is present in the universe will contain traces of almost any other physically possible molecule, including a large number of "toxic" components. Most often, it will contain "toxic" components at detectable levels - for instance, tap water regulations allow for arsenic at detectable concentrations, not because the lobby of water distribution is out to poison our children, but because there is a mountain of scientific studies studying the dose–response relationship for arsenic and saying it basically has no effect below this threshold. (Nonetheless, the water lobby or cost-cutting politicians may still come afterwards to make sure regulations aren't properly enforced though.)

The real question, in a context of health and safety, is whether the emanations from the cell phone cause measurable health trouble under various realistic scenarii. If you have access to the original article to which AD linked above, you could see the concentrations they measure and compare with epidemiological studies - my guess is that the toxic gases will be well below the threshold at which a health effect is demonstrated - if it wasn't, it would have made headlines in the scientific press. Tigraan^{Click here to contact me} 21:01, 27 December 2016 (UTC)

Meanwhile, until we are sure that emanations are below any danger limit, it would be wise not to sleep with your mobile phone right under your nose, especially if you are fast-charging it at the time, and it would be unwise to put your mobile phone on the fire, or in a hot oven, especially if you also have your head in it at the time. To answer the original question: ones which have had their batteries removed. Dbfirs 21:25, 27 December 2016 (UTC)

Rather the opposite in fact. The emanations they measure are seriously unpleasant and at high concentrations. However they're not released in normal service. A valid paper is wholly misrepresented by the IBT article - which is fairly typical for the IBT. Andy Dingley (talk) 21:49, 27 December 2016 (UTC)

Yeah I'm not sure why Tigraan doubts that a combusting battery may release gases in concentrations sufficient to be harmful since plenty of products will do so. Nil Einne (talk) 23:35, 27 December 2016 (UTC)

I somehow missed the bit about setting the batteries on fire in the article's abstract. But even then, my main point stands - it's a game of numbers. Either you can go through the paywall and start discussing the values that lie behind, or you are bound to speculate one way or the other. Sure, I will grant you that it is more than plausible that fumes from a burning battery are toxic, but to prove it you need the numbers. Tigraan^{Click here to contact me} 16:48, 28 December 2016 (UTC)

Read the article, via the doi link above. It's not paywalled (or else I've bulk-paid Elsevier somehow and didn't notice). Andy Dingley (talk) 20:35, 28 December 2016 (UTC)

Yeah it's not behind a paywall so I'm not sure why this was brought up. Also I'm not sure what's this fixation with the numbers. Of the four compounds quantified the authors specially noted the levels of CO were a concern. There was no commentary on the other 3. Sure it's always useful to look at they numbers yourself, but ultimately if you don't trust the authors to correctly note the risk you should question if you can even trust their measurements. Either way it isn't speculation to note the authors consider the level of CO a concern. In any case even if the main point has some limited truth too it it's largely missing the forest from the trees. The reason why you don't have to so concerned about this and it didn't make waves in the scientific press is because the results are not surprising and only a concern in a limited set of circumstances and definitely not to ordinary usage of the products. Even without these results you should be concerned if your battery combusts and not just because of what may be emitted. And yes it is silly to "guess is that the toxic gases will be well below the threshold at which a health effect is demonstrated". There's a very good chance the levels of something will be a concern if in a sufficiently closed and small space when you're combusting something as complex as a lithium ion battery and enough of them (well total capacity is a decent measure). It may still be a guess without the paper, but Tigran was the first person to make a guess even after the non paywalled paper was presented and so the obvious question is it a good guess, and the answer seems to be a clear cut no assuming a basic reading of even the flawed IBT article or the title of the paper or just what was noted here before the reply which Tigran was aware of (IE the recognition we are talking about combusting batteries) . Nil Einne (talk) 21:44, 28 December 2016 (UTC)

Traditional and Western medicines

My Chinese friend says that some Western medicines are based on TCM herbs and some Western people go to poor countries, ask the local people about local herb medicines, then steal the info to make Western medicines. Is that correct and if yes, more info and examples? --Curious Cat On Her Last Life (talk) 23:38, 27 December 2016 (UTC)

Err... yes and no. Many 'old wife’s' remedies are ridiculous. Yet not all. The Indian Government set up this site for the very reason that western pharmaceutical companies were attempting to demand royalties on traditional treatments. Will leave it to it to a quack, to explain how, that when one has a patent they go out of their way to ban the original. Willow Bark or an Aspro anyone? Oh! What a coincidence. --Aspro (talk) 00:01, 28 December 2016 (UTC)

Do you mean a quack or a shyster? —Tamfang (talk) 01:44, 30 December 2016 (UTC)

On the topic of TCM. Artemisia annua is a very effective anti malarial, yet the ( very expensive) patented synthetic equivalent based on this herb is less so. Make your own minds up. Should one venture into a an area of 'black water fever' your quack can only prescribe a less effective treatment by the law laid down by the FDA, who purpose is to protect the healthy profits of the pharmaceutical companies. --Aspro (talk) 00:28, 28 December 2016 (UTC)

@Aspro: peddling Big Pharma conspiracy theory and your anti FDA rhetoric has no place on the ref desk. The ACT treatments are expensive because they cost more to produce (than the very cheap old Chloroquine based drugs which no longer work very well), and the FDA has nothing to do with companies in Europe selling drugs in Africa. The truth is a LOT more complicated. Many of the drugs in Artemisnin combination therapy are not patented and have generic versions, such as Artemether and Artesunate, they are just more expensive to produce. Do a bit of research and cite some relevant articles, maybe you should keep your opinions to forums like prison planet or abovetopsecret. Vespine (talk) 00:44, 29 December 2016 (UTC)

Just pointing out, that once a pharmaceutical company has been awarded the patents it can sell it products for 600% or more of its manufacturing costs Ie. A lot more than its natural derivative! Sometimes even more: Pfizer hit with record fine after hiking price of NHS epilepsy drug by 2,600pc - costing taxpayer millions Further, they concentrate on isolating and marketing the pure (?) active ingredient that mosquitoes etc. can quickly adapt too rather than including other synergistic compounds in the natural source that also contribute towards protection. This profit motivated science has led to the development of antimalarials that cause psychosis and other side effects The risk of severe depression, psychosis or panic attacks with prophylactic antimalarials. Better to end up all screwed up than dead, the pharmaceutical companies might say, and go on to make a further killing by offering more of drugs to treat the the side effects. It is a win-win for them and their share holders wouldn’t you say? Would 'not' you say?!
“That is partly because of a glut in agricultural artemisinin. For the past two years, the naturally derived chemical has sold for less than $250 per kilogram — below Sanofi’s ‘no profit–no loss’ margin of around $350–400 per kilogram.” [2] . So that knocks your argument out of the window that (your quote) : “they are just more expensive to produce”. The pharmaceutical companies are just like any other industry – they seek to make as much profit as possible. Pharmaceutical conglomerates have seen to it that your doctors is now restricted -by law (via the FDA) , to being able to prescribe their products only . So reject and object to your uniformed and un-researched naïve comments that supports profit making; before effective inexpensive, affordable treatments and prophylactics. --Aspro (talk) 14:45, 29 December 2016 (UTC)

"uniformed and un-researched, naive" Oh please, you are so full of shit. So that knocks your argument out of the window that (your quote) : “they are just more expensive to produce”. No it doesn't, the synthetic artemisinin is more expensive to produce, that's exactly what the article says, the synthetic version "missed the market" because the agricultural one dropped in price, due to increased produciton. Do you have a comprehension issue? The conclusion section of the pubmed paper you yourself linked says CONCLUSION: The absolute risk of developing psychosis or panic attack appears low with all the antimalarials tested. No evidence was found in this large observational study that mefloquine use increased the risk of first-time diagnosis of depression when compared with the use of other antimalarials investigated in this study. Is that the complete opposite of the point you were trying to make? "uninformed" indeed. Also i never said i support profit making over cheap and effective therapies, that's you "pigeon holing" me into whatever big bad pharma shill you think I am, but no one is arguing that "cheap and effective" therapies of the past are no longer effective. I've argued with people like you quite a bit and i know it's a complete waste of time, you link articles you don't even read, you somehow draw the opposite conclusions from articles that seem quite clear. Global incidence of malaria is down 60%. That's not thanks to TCM, that's thanks to Artemisinin-based combination therapies developed mostly by those greedy bastard pharma companies with thanks in no small part to funding by the bill and melinda gates foundation. Not sure what planet you live on but on earth that doesn't happen for free. Vespine (talk) 05:12, 30 December 2016 (UTC)

If alternative medicine (e.g. TCM) works it becomes medicine. (((The Quixotic Potato))) (talk) 06:17, 28 December 2016 (UTC)

In an ideal world, where no oxen are gored. —Tamfang (talk) 01:45, 30 December 2016 (UTC)

We don't seem to have an article about this phenomenon, but yes, it exists. One case is Hoodia, a plant known to the Bushmen (San) people of southern Africa as an appetite suppressor. The pharmaceutical industry found out about this potential treatment for obesity, and a generation later, the plant is under threat of extinction, the Bushmen are as poor as ever, and the isolated component is apparently too toxic to be usable. You may find other examples with better outcomes by browsing Category:Medicinal plants by tradition. Carbon Caryatid (talk) 11:24, 28 December 2016 (UTC)

Nota bene: "the genus became internationally known and threatened by collectors, after a marketing campaign falsely claiming that it was an appetite suppressant for weight loss". And of course the San people are not Chinese. At least 99% of TCM is BS. (((The Quixotic Potato))) (talk) 11:27, 28 December 2016 (UTC)

Indeed. I was responding to the query about "some Western people go[ing] to poor countries". I understand that 99% of drug candidates are found not to be usable, for one reason or another. Carbon Caryatid (talk) 11:54, 28 December 2016 (UTC)

This rather gives the impression Japan has been focused on isolating that 1%. A lot of the pharmacies I've seen here in China can be pretty frightening, though. Then again, regulation and testing makes a hell of a lot of difference. The Barefoot doctor's Manual (if not censored by New Age "alternative" medicine companies) labels the traditional medicine with 'only do this if you have absolutely nothing else to work with and even that has failed.' Ian.thomson (talk) 11:05, 30 December 2016 (UTC)

By the way, the general field is called ethnobotany, which our article defines as "the study of a region's plants and their practical uses through the traditional knowledge of a local culture and people <snip> including, but not limited to, plants as medicines, foods, and clothing. ".Carbon Caryatid (talk) 11:58, 28 December 2016 (UTC)

The specific allegation is "biopiracy", but that is a very broad political term applied to benefit very specific people. The 'fix' generally involves privatizing the public domain, but they say it's for a good cause. (The Hoodia article cited above is a good example: someone claims a patent on something well known for centuries, and the fix is to share the profits with the tribe!) Ahem. I think that capitalism has become more of a religion than a workable scheme for organizing an economy at this point, and this is one example of that. There are a great many TCM treatments that are effective - most notably, the Chinese take flack for raising bile bears whose gall contains ursodeoxycholic acid (which now can be synthesized), while in the West they are more happy to simply take out your gallbladder and leave you with digestive problems instead. "Ethics" is just another word for profit. Wnt (talk) 16:29, 28 December 2016 (UTC)

References

Did you seriously just allude that having your gall bladder removed by western medicine, is less "ethical" than how bile is farmed from bile bears in china? And that the former is profit but the latter isn't?? Did you also know that the main reason rhinos and elephants are still being poached to this day is because of the growing market in TCM? Which as far as I know NONE of the Chinese "medicines" derived from African animals do ANYTHING medical whatever, it's pure "magic potions", do you think ANYTHING other than profit drives those poachers? Some people think it's all "black and white", it either works or it doesn't, it's either ethical or it isn't, but the truth is always far more complicated, medicine is always about cost vs benefit and risk vs reward. Of course there are risk associated with having your gall bladder removed, but to suggest for a second that in every single case the alternatives are not weighed up is ridiculous. You honestly think surgeons are removing gallbladders for fun? Vespine (talk) 09:40, 30 December 2016 (UTC)

"there is no evidence that bear bile has any medicinal effect" and "Raw bile can sell for as much as US$24,000 per kg, about half the price of gold." So... how's that for focusing on people instead of profits? Ian.thomson (talk) 11:15, 30 December 2016 (UTC)

It's really a curious argument that alt-med fanatics use, "big pharma only cares about profits." Probably true. I mean, I'm sure many of the individual employees are actually interested in curing disease, and perhaps some of the smaller biotechs are idealistic, but the investors are probably mostly into profit, as in any other industry. The alt-med industry, on the other hand, is happy to sell anything with no good trials for safety or efficacy, just like big pharma did before the industrialized nations started requiring it by law. Somehow that's seen as less selfish. I'll never get it. Someguy1221 (talk) 11:53, 30 December 2016 (UTC)

@Vespine: What I seriously alluded to is that whenever you have a health problem, wherever you are, there will be a long line of schoolyard bullies standing between you and the cure looking to take every cent you have on the way, and it doesn't really matter what philosophy it is. Obviously I'd like to see people avoid gall bladder removal whenever possible using gentle treatments like ursodeoxycholic acid, while avoiding the ridiculously elaborate and rather gruesome antiquated scheme some use to get it. And yes, I think that unnecessary surgery is a standard practice when it makes a reliable profit, recent-past examples being hysterectomy and tonsillectomy. Wnt (talk) 12:39, 30 December 2016 (UTC)

Biopiracy, thank you, I had forgotten the term. I see that they take hoodia as a key example. Carbon Caryatid (talk) 17:33, 28 December 2016 (UTC)

Thanks for the answers! The links to biopiracy and the Indian website and ethobotany are very useful. Can see have two sides to this. Aspro and Carbon and Wnt on one side, Vespine and Quixotic and Ian on other side. Here I live Western medicines are very expansive and have some charitys have free TCM clinics to help poor people. The TCM doctors learn local languages even better than the Western doctors here. Also want to say that I ask not only about TCM, also other traditional medicines. If the traditional medicines can add to Western medicines is good but must be fair to non Western people (not steal). --Curious Cat On Her Last Life (talk) 12:31, 30 December 2016 (UTC)