Wikipedia:Reference desk/Archives/Science/2013 November 19
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November 19
[edit]Tea for sore throat
[edit]How does tea with honey and/or lemon help hoarseness if food and drink descend down the esophagus and hoarseness originates in the larynx? DRosenbach (Talk | Contribs) 02:35, 19 November 2013 (UTC)
- The Mayo clinic confirms that honey and lemon tea are both shown to be effective cough suppressants in clinical trials, but does not present a mechanism for how they work; merely noting that honey is shown to suppress coughs in children as effectively as dextromethorphan. --Jayron32 03:13, 19 November 2013 (UTC)
- The obvious answer is vapors. For clearing my sinuses, I like to make a "tea" by dissolving menthol-eucalyptus cough drops in boiling water. That tea goes down my esophagus, too, but the vapors clear my sinuses right out. StuRat (talk) 03:43, 19 November 2013 (UTC)
- I think every medicine has a "mechanism is unknown" in the PDR references. They can do studies to prove efficacy and limit side-effects but metabolism is so complex that it's generally impossible to have a complete mechanism. Therefore most of it is statistical. Kind of scary if you ask me. (I think they may finally have a complete mechanism for aspirin). Read a PDR on drug mechanism to be completely disheartened. --DHeyward (talk) 07:21, 19 November 2013 (UTC)
- Yes, I just commented on this in another Q, how much of western medicine really is just trial-and-error, without knowing why things do what they do. StuRat (talk) 07:41, 19 November 2013 (UTC)
- Not to mention being in part snake oil, as we see when pharmaceutical companies are forced to re-run clinical trials under more rigorous protocols. —Quondum 13:28, 19 November 2013 (UTC)
- It's not like we know any more about honey and/or lemon. Honey having "anti-bacterial properties" as mentioned below is just as unknown a mechanism as other medications. Neither more understood or better than any other. --DHeyward (talk) 02:38, 20 November 2013 (UTC)
- Not to mention being in part snake oil, as we see when pharmaceutical companies are forced to re-run clinical trials under more rigorous protocols. —Quondum 13:28, 19 November 2013 (UTC)
- Yes, I just commented on this in another Q, how much of western medicine really is just trial-and-error, without knowing why things do what they do. StuRat (talk) 07:41, 19 November 2013 (UTC)
- The heat of the tea will act as a painkiller, while the steam will carry the oils of the lemon into the sinuses. Honey is well known for its antibacterial properties. The larynx and associated soft tissues are close enough to the oesphagus to benefit from the heat of the tea. It's not just the larynx that may be inflamed or infected: the pharynx may be as well, or the tonsils or adenoids or the other fleshy parts. --TammyMoet (talk) 13:23, 19 November 2013 (UTC)
Our article on swallowing mentions that true vocal fold closure is the primary laryngopharyngeal protective mechanism to prevent aspiration during swallowing. The article is lacking in sources but see for example here. The epiglottis will fold over and cover the glottis, the upper esophageal sphincter first relaxes to allow the food or drink to pass into the esophagus and then contracts to reduce backflow into the pharynx. For liquids, this process won't be one hundred percent effective, there will always be some liquid sticking to the mucous tissue which may be redistributed when one swallows the next sip. Honey, with it's greater viscosity and stickiness may be able to reach the vocal cords this way. but that's pure speculation on my part. A youtube video showing the vocal cords and the epiglottis during swallowing here, and one showing radiology of someone swallowing barium here. Ssscienccce (talk) 14:37, 19 November 2013 (UTC)
- "...clear my sinuses right out," and "... carry the oil of lemon into the sinuses", does that mean the nasal sinuses or the nasal conchae. If it is the former I am interested to know how the active agent enters the sinuses, given that access and egress is through a very small, and tight, meatus surrounded by cilia sweeping outwards. Sorry DR, well off topic, but sometimes one has to question stuff that people say. Richard Avery (talk) 15:25, 19 November 2013 (UTC)
- You're quite right to question me Richard, and I'm wary of quoting my sources on here because I've been told off for quoting pseudoscience about aromatherapy before. The essential oil will be vaporised by the heat and carried by the steam into the nasal cavity, and from there into the sinuses at the front of the face, when the steam from the tea is inhaled. --TammyMoet (talk) 20:02, 19 November 2013 (UTC)
- Well, I don't know for certain how it works, only that it works. It's quite possible the vapors are inhaled up the nose while drinking from the cup. StuRat (talk) 23:54, 19 November 2013 (UTC)
- I can't definitively answer the OP's question either but I have a clue. In the UK, our equivalent is 'Simple Linctus.' [1] Something one gets from the drugstore that contains sucrose and citric acid. Many years ago when the these shops where shut for a bank holiday weekend I was given a tumbler of 'grandma’s' family sore throat cure. Ie., Tea with honey and lemon (and some of the zest). I can not rule out the placebo effect totally, because a spoon full of Simple Linctus just goes down the gullet where as a tumbler (about 1/3 of a pint) of warm sweet lemon tea is more enjoyable and may therefore, have put me in a more optimistic frame of mind. However, lets go back to the OP's question and the Larynx. I noticed (and other times since then) that as the hoarseness and soreness faded away, I stated to sound like Paul Robeson [2]. Being a natural baritone I found it delightful to go suddenly reallllly deeeeep. So to address Drosenbach question, I am wonder that if during a viral infection, the epiglottis (through evolutionary fitness) closes to prevent phlegm entering the larynx (and down into the lungs). Thus, causing dryness of the vocal cords. Honey and lemon (and not the proper prescribed tonic, which I now think does B*@@$& all) both soothes and relaxes the epiglottis and allows the vocal cords to become moist once more. Whilst at the same time allowing the odd bit of thick mucous to sometime coat the cords allowing me to sing “ Oh, That Old man river ... that old man river... --Aspro (talk) 22:30, 19 November 2013 (UTC)
Could a dog sense radon or the the effects of radon in a basement?
[edit]I know that radon is odorless, at least to us, but i wonder if a dog could smell it, or otherwise detect ionization from the radioactivity or smell the lead byproduct or or other byproducts. thanks!67.177.40.9 (talk) 15:07, 19 November 2013 (UTC)
- No, I don't think so.
- Radon itself is a "noble gas" - it doesn't react chemically with anything - which means (I believe) that it truly is odorless and tasteless, even to dogs.
- The radiation also has no "smell" because the sense of smell operates by detecting molecules using chemical reactions.
- I could easily believe that a dog could be trained to pick up some kinds of by-products. Radon changes to Polonium with a half-life of 3.8 days - which over a few minutes turns into lead. I doubt that enough polonium stays around for long enough for a dog to pick it up. But training a dog to sniff out minute quantities of lead ought to be possible.
- But there is a horrible snag. The problem is that the dog would need to detect very small quantities of lead - which I'm sure it could do - but there is almost certainly going to be lead from other sources in the area where you're trying to do the measurement. If you want the dog to sniff out radon by-products in someones' basement for example - then if it's sniffing for lead, it's going to find it in the solder joints of copper household piping, in the solder joints of any electronics, in pottery glazes...all over the place!
- Since the dog can't tell the difference between lead-from-radon and other sources, it can't detect the byproducts of Radon.
- So this hinges on whether it could smell the truly tiny number of short-lived polonium atoms in the few minutes between the radioactive decay of a radon atom and the polonium atom turning into lead. But polonium is almost as unreactive as radon - and also, polonium is found in places that might fool the dog - smoke detectors, for example, contain small amounts of the stuff - but in quantities that would dwarf the amount in the air of a radon-infested basement.
- I couldn't find a reference for any of this - but I'm pretty sure the reasoning is sound.
- A good undergrad-level chemistry question is "given the half-life of the relevant Rn isotope and the amount of radiation detected, what is the concentration of Rn in the air?" Helps focus attention on orders of magnitude...what can a radiation detector or (bio)chemical sensor detect and also sensitive instruments such as mass spectrometry (all the "immediate detection" methods vs requiring long-term collection/concentration steps). DMacks (talk) 17:27, 19 November 2013 (UTC)
- Another point to consider is the difference between the sensitivity of a detector and its accuracy. A dog's nose is very sensitive, so dogs are very good at detecting whether something (drugs, explosives, cancer cells) is present in a sample, but the important thing we need to know is how much radon is in the basement, which dogs aren't particularly good at communicating. Tevildo (talk) 18:42, 19 November 2013 (UTC)
- Physically, we know it is possible for some devices (Geiger counter) to detect the radon radioactivity. Therefore, there is no physical law that prevents the dog from detecting it with some similar function. It may seem far-fetched, yet it has been suggested at times that people living in areas with high background radiation have some ability to acclimate (radiation hormesis). That is a controversial idea itself, but clearly, if something can acclimate, if its biology is literally reacting to the radiation somehow, then in theory it could sense that and react to it by behavior also. At this point, the only biological answer possible is to do the experiment and see what happens. Wnt (talk) 18:44, 19 November 2013 (UTC)
- That's one hell of a stretch. Mainly though - even if by some as yet unknown mechanism, it were possible for a higher animal to detect radiation like that, why would you assume a dog could do it any better than a human or an aardvark? Sure there is a physical mechanism by which humans can detect high levels of radon gas - by breathing it for 30 years and dropping dead from lung cancer if radon gas is present. The problem here is not that there might or might not be some physically plausible way to measure it - the specific question is whether a dog can do it using it's superior sense of smell...and the answer is an almost-certain "No". Let's try not pretend to be clever by mudding the water and thereby confusing the people asking the questions here. SteveBaker (talk) 21:59, 19 November 2013 (UTC)
- "Common sense" is not very reliable in biology. For example, people have been studying cancer in mice for a century. Then one day someone happens to ask whether the risk of cancer depends on the temperature of the room. [3][4] And guess what? It's been throwing off the results. Before something very similar came out about common formulations for mouse chow. It's very important to keep in mind the difference between what you think is the answer and whether you know the answer in this field. There's no reason for dogs to have evolved to sense radiation unless somebody finds out they do it, at which point it will take a researcher or commentator all of five or ten minutes to come up with some just-so story to explain why they did. Wnt (talk) 12:26, 20 November 2013 (UTC)
- That's one hell of a stretch. Mainly though - even if by some as yet unknown mechanism, it were possible for a higher animal to detect radiation like that, why would you assume a dog could do it any better than a human or an aardvark? Sure there is a physical mechanism by which humans can detect high levels of radon gas - by breathing it for 30 years and dropping dead from lung cancer if radon gas is present. The problem here is not that there might or might not be some physically plausible way to measure it - the specific question is whether a dog can do it using it's superior sense of smell...and the answer is an almost-certain "No". Let's try not pretend to be clever by mudding the water and thereby confusing the people asking the questions here. SteveBaker (talk) 21:59, 19 November 2013 (UTC)
- Neither the shape theory of olfaction nor the vibration theory of olfaction would rule out smelling a non-polar substance. If the ability doesn't exist, it might be more of a case of (the lack of) selection for the relevant genes. μηδείς (talk) 22:23, 19 November 2013 (UTC)
- Xenon is a "noble gas" but does produce strange phenomena like anaesthesia. Shyamal (talk) 13:13, 21 November 2013 (UTC)
- But that is not a result of its chemical properties, right? Double sharp (talk) 14:33, 21 November 2013 (UTC)
- Xenon is a "noble gas" but does produce strange phenomena like anaesthesia. Shyamal (talk) 13:13, 21 November 2013 (UTC)
- To give some idea of the quantities involved: 1000 Bq/m3 would be considered a very high concentration for a house. One Bq is one atom decaying per second. Radon has a half-life of 3.8 days, reversing the calculation of Becquerel#Calculation_of_radioactivity gives us about half a billion particles (per cubic meter); that's about 8 x 10-16 of a mole, and with a cubic meter of air containing about 45 moles, the concentration in the air is about 1 particle in 5x1016. Dogs can detect explosives in concentrations of 1 ppb, and some dogs have been shown to detect some chemicals at concentrations down to 1 ppt. But even 1 ppt is 50,000 times higher than the radon concentration at 1000 Bq/m3. Considering the fact that a dogs nose will likely be much less (if at all) sensitive to radon and its progenies, the only way to detect radon would be if the concentrations were millions times higher than normal... Ssscienccce (talk) 16:09, 21 November 2013 (UTC)
- Thanks a lot to alot of people here, you have thought it thru carefully and taught me alot. But, aren't you neglecting the possibility of ionized radioactive byproducts? Aren't they rather reactive and couldn't that lead to ozone or ozone-like odors?67.177.40.9 (talk) 03:44, 22 November 2013 (UTC)
- Is radon normally found in the presence of other gases ? If so, do any of those other gases have odors the dog could detect ? StuRat (talk) 07:39, 22 November 2013 (UTC)
"Cyclone Cleopatra"
[edit]This storm recently killed a number of people in Sardinia. But do cyclones occur in the Mediterranean? Our cyclone article makes no mention of that area. Which type of storm is it? Who is the official name giving body for this storm? Or is this like The Weather Channel naming U.S. winter storms? Rmhermen (talk) 17:05, 19 November 2013 (UTC)
- Sort of quasi-cyclones -- see Medicane. Looie496 (talk) 17:28, 19 November 2013 (UTC)
- What's a medicane -- is it like our Witch of November? I presume it's not the brand name of a walking stick, or of a medicated candy cane ;-) 24.23.196.85 (talk) 21:30, 19 November 2013 (UTC)
- I couldn't find any reference to this kind of thing happening over the Mediterranean - Europe in general seems pretty much devoid of that kind of activity. One exception (which I recall well because I was living right in the middle of it at the time!) is the Great Storm of 1987 - which hit France and southern England - but not the Mediterranean.
- According to Hurricane#Naming, hurricanes are named either by the World Meteorological Organization according to a fixed rota of alphabetically consecutive names - or sometimes by national weather offices. Tornadoes are generally named after the place they touch-down - but it's all a bit informal. We have an entire article about Tropical cyclone naming.
- That same article says "Tropical cyclone formation is rare within the Mediterranean sea...and as a result there are no official naming lists for these areas.". Evidence, again, the Great Storm of 1987 - which had no 'official' name but is universally known in the UK just as "The Great Storm" and the Burns' Day storm which is named for the birthday of Robert Burns (a Scottish Poet).
- European windstorms (which are really "extratropical cyclones" tend to go north of the Mediterranean - mostly missing Europe completely. There is a section in that article that explains the naming system...but it's not a well-organized, or recognized system - and different countries frequently give the same exact storm different names.
- SteveBaker (talk) 17:31, 19 November 2013 (UTC)
- Well, European windstorms mostly miss continental Europe, but they frequently hit Scandinavia. In the British Isles, they frequently hit Scotland but rarely make it down to England. If they hit England they can do a lot of damage, but in Scotland, as somebody said, they usually just knock the cows over. Looie496 (talk) 17:57, 19 November 2013 (UTC)
- With global warming, I bet hurricanes in the Mediterranean Sea will become more common, so perhaps they need to set up a system to name them now. StuRat (talk) 07:43, 22 November 2013 (UTC)
3D printed stainless steel?
[edit]I saw an advertisement for an artsy bottle opener that said it was "3D printed stainless steel". This seems a little beyond 3D printing technology as I know it. How would this be possible? --209.203.125.162 (talk) 18:48, 19 November 2013 (UTC)
- If you Google "3D printed stainless steel" or similar, you'll find lots of services that provide exactly that. Shapeways has a 3D printed stainless steel Klein bottle-shaped bottle opener that shows up on their main page. TenOfAllTrades(talk) 19:34, 19 November 2013 (UTC)
- (ec) Doing it properly involves Selective laser melting - alternatively, according to this website, "3D printers deposit small drops of glue onto layers of stainless steel powder, one layer at a time, until the print is complete.... The models then go through an infusion process that replaces the glue with bronze, creating a full metal product." Your bottle opener is probably made by the latter method, but it can be done. Tevildo (talk) 19:35, 19 November 2013 (UTC)
Tank duel revisited
[edit]In a tank duel between our Sherman tank and the Russian T-34, which side is more likely to win? And what factors (if any) would help one side or the other? 24.23.196.85 (talk) 22:02, 19 November 2013 (UTC)
- We don't do speculation here. SteveBaker (talk) 00:15, 20 November 2013 (UTC)
- Our article discusses this for late models of each tank. See Sherman tank#Post–World War II. Rmhermen (talk) 01:10, 20 November 2013 (UTC)
- Thanks! So, slight advantage for the Sherman because of better optics and a higher-velocity main gun, just like I suspected? 24.23.196.85 (talk) 03:32, 20 November 2013 (UTC)
- Not necessarily. That section seems rather incomplete. See Sherman versus T-34 for more pros and cons. I'm no expert, so I can't voice an opinion of its accuracy, but it doesn't contradict what little I've read. Clarityfiend (talk) 06:22, 20 November 2013 (UTC)
- Our article on the T-34 mentions that the Germans operated a number of captured T-34s. I wonder if any of these were used on the western front, which may have given us an actual example of T-34 vs. Sherman combat. Someguy1221 (talk) 06:27, 20 November 2013 (UTC)
- According to this forum, no. It really wouldn't make much sense to ship them across Europe. A better scenario is one of the 4102 Soviet Lend-Lease Sherman tanks vs a captured T-34 on the Eastern front, but I'm sure somebody would have brought it up long before if it had happened. Clarityfiend (talk) 04:33, 21 November 2013 (UTC)
- Our article on the T-34 mentions that the Germans operated a number of captured T-34s. I wonder if any of these were used on the western front, which may have given us an actual example of T-34 vs. Sherman combat. Someguy1221 (talk) 06:27, 20 November 2013 (UTC)
- Not necessarily. That section seems rather incomplete. See Sherman versus T-34 for more pros and cons. I'm no expert, so I can't voice an opinion of its accuracy, but it doesn't contradict what little I've read. Clarityfiend (talk) 06:22, 20 November 2013 (UTC)
- Thanks! So, slight advantage for the Sherman because of better optics and a higher-velocity main gun, just like I suspected? 24.23.196.85 (talk) 03:32, 20 November 2013 (UTC)
- Our article discusses this for late models of each tank. See Sherman tank#Post–World War II. Rmhermen (talk) 01:10, 20 November 2013 (UTC)