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November 16

Fear of abortion

trolling
The following discussion has been closed. Please do not modify it.

What would the name be, and would it be considered a mental disorder if it incited someone to act violently? -- CensoredScribe (talk · contribs)

The name would be "Fear of abortion". Not every concept needs other words to describe it. Often, the words that already exist are sufficient. --Jayron32 01:03, 16 November 2013 (UTC)[reply]
If what incited someone to act violently? And who's asking? μηδείς (talk) 01:15, 16 November 2013 (UTC)[reply]
It was CensoredScribe. And I suppose it could be "abortionphobia", if there were such a thing. I've never heard of anyone who "feared" abortion. Some favor abortion rights, some oppose, some are neutral. If he's talking about what characters like Eric Rudolph did, that's not abortionphobia - it's just plain terrorism. ←Baseball Bugs What's up, Doc? carrots→ 01:43, 16 November 2013 (UTC)[reply]
Fear of Genocide? We acted pretty violently to stop the Nazis. --DHeyward (talk) 03:07, 16 November 2013 (UTC)[reply]
DH is right. Forced abortion? Induced abortion? Spontaneous abortion? If the OP wants a reasonable answer he should clarify himself. μηδείς (talk) 03:12, 16 November 2013 (UTC)[reply]
"Incited someone to act violently" isn't the deciding factor. Something can be a mental disorder without any violence, and not all the things incite violence are considered mental disorders. There are many things called "fear of…" or "…phobia" are not mental disorders, as our article Phobia mentions. You need to clarify if you mean the clinical or the non-clinical meaning of the term.Sjö (talk) 09:55, 16 November 2013 (UTC)[reply]
Somebody wise said that more evil has been done in the world because of the love of a leader than because of the hatred of an enemy. An anti-abortionist acting violently over that issue is most likely showing an over-the-top love of his Christian god, whose earthly spokesperson told him that abortion was a bad thing that must be prevented (at all costs). HiLo48 (talk) 10:24, 16 November 2013 (UTC)[reply]
Or not. --DHeyward (talk) 10:38, 16 November 2013 (UTC)[reply]
That's a bit of a distorted way of looking at things, most people wouldn't call that genuine love. It'd be like saying that a jealous husband who beats his wife does it out of an over the top love for her. It's not that you can't contort the phrase to make that technically work, but without specifying a bunch of "I mean this by this" 's, it sounds like you're saying something very different than what you are, and which isn't actually accurate.Phoenixia1177 (talk) 11:07, 16 November 2013 (UTC)[reply]
I did say "over the top love". It was meant to describe something irrational. HiLo48 (talk) 11:27, 16 November 2013 (UTC)[reply]
True, I apologize. I've seen a lot of statements like the one you made (on both sides of the fence) used to distort issues, so I'ma bit bitchy about them. Sorry, I honestly didn't intend for that to come off as it did:-).Phoenixia1177 (talk) 11:32, 16 November 2013 (UTC)[reply]
That does not suggest "fear", it's more like "righteous indignation". The idea of "fearing" abortion only makes sense in terms of the embryo or fetus (who doesn't know what's happening anyway); and the mother contemplating an abortion but being fearful of the procedure. Neither of those scenarios suggests consequent murder-and-mayhem by the respective parties. ←Baseball Bugs What's up, Doc? carrots→ 16:25, 16 November 2013 (UTC)[reply]
The prejudiced legal tactic of 'homosexual panic', and subsequently the inept word 'homophobia', has engendered many abuses of the English language, in which ideological hatred and irrational fear are confounded. 'Islamophobia', for example. To continue this sorry trend, one need only look up abortion in Greek (the older the Greek, the better) and attach -o-phobia. Looking up on the web I came up with two of the big ones, then finally went to a decent source: http://www.lexilogos.com/english/greek_ancient_dictionary.htm . This gets stuff like ἄμβλωμα / ἄμβλωσις , ἀπόφθαρμα , ἔμβρημα , ἐξάμβλωμα . A drug to produce abortion is φθορεῖον , and procuring abortion is διαμβλώττω . It would help of course to narrow down the 'phobia' desired - is it the fear of a pregnant woman that someone will hold her down or poison her, or is it (as I suspect) the fear by someone of having it legally practiced in a community? (Or, more specifically, the fear of a husband having his child taken without his consent, contrary to the Code of Assura?) In any case, one need merely transliterate the various roots, which I shall most inexpertly, missing many nuances, do as amblōma / amblōsis , amophtharma, embrema, examblōma; phthoreion, diamblōttō. Searching I didn't find amblosophobia, amblomophobia, amophtharmophobia, embremophobia, examblomophobia, phoreiophobia, or diamblottophiba (also tried -osso-). I could very readily have missed some variation, but my guess is that you have an open field here to pick whichever one you like the best, and in ten years people may be using it to sound 'educated', and in 20 to avoid appearing politically incorrect. Wnt (talk) 17:42, 16 November 2013 (UTC)[reply]
Spot on, Wnt. We've had this same "what do you call the insanity of (insert socially conservative position here)" before, recently in regard to homophobia and islamophobia. Perhaps someone can suggest a term for leftist political trolling at the wikipedia ref desks. μηδείς (talk) 20:00, 16 November 2013 (UTC)[reply]
Leftist? Now, there's a seemingly simple but appallingly misused word! HiLo48 (talk) 20:50, 16 November 2013 (UTC)[reply]
Says the raving Leftist. μηδείς (talk) 21:28, 16 November 2013 (UTC)[reply]
Define raving. HiLo48 (talk) 21:44, 16 November 2013 (UTC) [reply]
Simple, lol. By definition all Leftists are raving. The political trolling per se is the problem though. We just so rarely get things like this it can be monotonous. μηδείς (talk) 03:36, 17 November 2013 (UTC)[reply]
The thing is, though, that while attaching "-phobia" to "homo" and "Islam-o" carries a measure of political bias, there are people who are actually afraid of homosexuals and/or Muslims. When have you ever heard of someone being "afraid" of abortion? ←Baseball Bugs What's up, Doc? carrots→ 23:17, 16 November 2013 (UTC)[reply]
It is hard to believe that there is not a feature horror film, based on some corresponding story of a few pages from H.P. Lovecraft, entitled The Abortionist. "My senses swirled about me as I giddily stumbled into that final chamber, and my unbelieving eyes absorbed the truth of Gosnell's dark rituals. My gaze darted from the minute and carefully preserved faces of the dead to the pulsing entrails of the living, but infinitely more disturbing was the thing -- how dare I speak of it? -- the proud result of all Gosnell's experiments, which looked up from its orgiastic feeding of primordial life-force to behold me with eyes, such eyes, perfect youth and vigor, infinite age and malice! Wnt (talk) 00:54, 17 November 2013 (UTC)[reply]
I don't follow. Who is it, in that quote, who's "fearing" abortion? ←Baseball Bugs What's up, Doc? carrots→ 00:57, 17 November 2013 (UTC)[reply]
A patient at Arkham Asylum, I should suppose. If people are afraid of cemeteries, of houses where people died, why not abortion clinics? :) Wnt (talk) 01:03, 17 November 2013 (UTC)[reply]
The OP asked about fear of abortion, not fear of clinics. It would be nice if he would come back here and explain just what he was trying to ask. ←Baseball Bugs What's up, Doc? carrots→ 01:15, 17 November 2013 (UTC)[reply]
That would be a first. Trolling is even less fun than humor when you have to explain it. μηδείς (talk) 03:40, 17 November 2013 (UTC)[reply]
And Islamophobics are afraid of turbans -- more often than not, the guy they pick out of a crowd to beat up is a Sikh... Wnt (talk) 01:41, 17 November 2013 (UTC)[reply]
Kind of the way acrophobics beat up cliffs and skyscrapers? The term you want is ignorant bigot, Wnt.μηδείς (talk) 03:40, 17 November 2013 (UTC)[reply]
Well, as I suggested above, I don't see these 'phobias' as true phobias. While people can be afraid of any number of things based on prejudice, that fear is based on the prejudice and rational deduction from that premise rather than the other way around. Wnt (talk) 04:26, 17 November 2013 (UTC)[reply]
Whether "true phobia" or not, I would still like to see Censored Scribe define exactly what he means by "fear of abortion". ←Baseball Bugs What's up, Doc? carrots→ 14:09, 17 November 2013 (UTC)[reply]
The OP has posted a number of times to other pages since the post here. I have asked him to explain what "fear of abortion" is supposed to mean. If we don't get an answer by his next post, I recommend the entire thread be boxed or deleted as trolling. ←Baseball Bugs What's up, Doc? carrots→ 14:13, 17 November 2013 (UTC)[reply]
Mental illness is not required for being a phobic - being stupid is often sufficient. ←Baseball Bugs What's up, Doc? carrots→ 03:15, 17 November 2013 (UTC)[reply]

spaceship water shielding

I just watched the film Europa Report, which I had heard was remarkably scientifically accurate (for being a science fiction movie). During one scene, a crew member ejects what they call "water shielding". It's never shown what it is, but it apparently was very heavy. Is this a real thing, or a sci-fi invention? --209.203.125.162 (talk) 01:51, 16 November 2013 (UTC)[reply]

Neutron can be very dangerous.
You need water. There must be a water storage on a spaceship. A water molecule is one oxygen plus two hydrogen atoms (one neutron + one electron). Hydrogen is really good at stopping neutron. A water shield is a water tank made to shield astronauts from dangerous cosmic radiation. I think it's also a good idea to use food (contains water), fuel (especially liquid hydrogen) and anything that can be used to protect astronauts to create a wall between a spaceman and the space. -- Toytoy (talk) 02:33, 16 November 2013 (UTC)[reply]
Ummmm, what? That hydrogen thing. Uhhh, no. Just no. --03:10, 16 November 2013 (UTC)
These all mention water shields: [1], [2], [3], and [4]. The idea is as above, using water to shield the crew from radiation.Phoenixia1177 (talk) 07:36, 16 November 2013 (UTC)[reply]
Our article on Radiation protection mentions the use of water as shielding a couple of times. Someguy1221 (talk) 08:05, 16 November 2013 (UTC)[reply]
If they could go to Europa then robots could easily have got ice from comets for shielding, and anyway I'd hope they'd use robots on Europa before sending people!. Until then though I'm a bit sorry they just destroy satellites at the end of their life rather than moving them all together into a single mass in a higher orbit to use as shielding or as raw materials for future missions. Dmcq (talk) 10:58, 16 November 2013 (UTC)[reply]
On a space trip, water can be used for shielding a human crew from radiation during solar flares. Water as such is not a magic substance that is particularly good for a shield; any substantial mass of matter will do. In scenarios such as going to Mars water and food are often mentioned as radiation shields because you'll have those things for drinking and eating anyway. You could bring along a big block of lead but that doesn't have the dual use that a tank of water has. I'm not sure why you'd eject the water though because after you use it for radiation shielding it's still good for drinking, bathing, growing plants, flushing your toilet, etc. 88.112.41.6 (talk) 20:57, 16 November 2013 (UTC)[reply]
Europa Report#Plot says: "The crew agrees to leave in order to bring their discovery back to Earth, but the engines malfunction. As the ship hurtles back to Europa's surface, Xu unbuckles from his seat to remove water shielding to reduce the impact speed." So the plan was presumably to keep the water for the home trip. PrimeHunter (talk) 11:35, 17 November 2013 (UTC)[reply]
If neutrons are what you're shielding against, then wouldn't something like beryllium, boron or cadmium make a better shield than water? 24.23.196.85 (talk) 02:22, 17 November 2013 (UTC)[reply]

In a nuclear war, you need water to shield you from neutron.

Now I think you may need to shield yourself from gamma ray in deep space. -- Toytoy (talk) 10:36, 17 November 2013 (UTC)[reply]

I had a look once at a radioactive pile in a deep pool of water. It had a pretty blue glow all around it. I'd probably be dead now if the water wasn't there. Dmcq (talk) 11:32, 17 November 2013 (UTC)[reply]
In the case of radioactive waste storage, the water is there not just to absorb the radiation -- even more importantly, it's there to absorb the heat generated by the radiation, which would otherwise melt or ignite the radioactive waste and disperse radioactive smoke all over the place (as happened at Chernobyl, although in that disaster, the initial dispersion was due to an explosion). And yes, gamma rays are a serious danger in space. 24.23.196.85 (talk) 01:57, 18 November 2013 (UTC)[reply]

Heavy water is probably a better candidate for radiation shielding. — Preceding unsigned comment added by 168.178.74.25 (talk) 22:34, 18 November 2013 (UTC)[reply]

No, ordinary water is better for neutron shielding -- it absorbs neutrons better (which is why they have to slightly enrich the uranium for light-water PWR and BWR type reactors, but not for the heavy-water CANDU type). As for shielding against gamma rays, both kinds of water are equally ineffective -- gamma-ray shielding requires lead, concrete or heavy armor plate (or a combination of the three). 24.23.196.85 (talk) 07:39, 19 November 2013 (UTC)[reply]
It's just you need a much smaller thickness of lead, it depends more on the total mass and lead is much denser than water. A deep pool is quite effective against gamma rays. Dmcq (talk) 12:55, 19 November 2013 (UTC)[reply]
If you're concerned at all about weight (as would be the case in any aerospace application), then lead or armor plate would be the best choice. 24.23.196.85 (talk) 21:44, 19 November 2013 (UTC)[reply]

You are saying that regular water is better than the heavy water, then how about the Norwegian hydroelectric plant in WWII that produced heavy water for the Nazis? Why did people risk their lives to destroy it and deprive them of this vital material for a nuclear bomb? — Preceding unsigned comment added by 168.178.74.104 (talk) 16:57, 19 November 2013 (UTC)[reply]

No, no, no, you got it all bassackwards -- the Nazis used heavy water as the MODERATOR for their reactor, not as SHIELDING! The role of the neutron moderator is not to shield the operator from neutrons -- it's specifically to slow the neutrons down INSIDE the reactor so they have time to react with the uranium (or plutonium) instead of flying out like they would do at the speeds at which they normally fly! And since the moderator's purpose is to help the neutrons react with the uranium, the best moderator is one that would slow the neutrons down effectively WITHOUT absorbing them -- which is what heavy water does, which is why it's better than ordinary water AS A MODERATOR! Whereas if you want SHIELDING, you want to ABSORB neutrons or REFLECT them rather than just slow them down -- which is why ordinary water would be better FOR SHIELDING than heavy water. 24.23.196.85 (talk) 21:44, 19 November 2013 (UTC)[reply]

Lecithin

The article says it lowers cholesterol. Is the source good? Thanks. 67.243.4.94 (talk) 02:08, 16 November 2013 (UTC)[reply]

If you're concerned about yourself or someone else with high cholestoral, you should follow your doctor's orders on the matter. ←Baseball Bugs What's up, Doc? carrots→ 02:22, 16 November 2013 (UTC)[reply]
Since lecithin is a nutritional supplement, not a medicine, advice on when to take it is not medical advice. StuRat (talk) 02:40, 16 November 2013 (UTC)[reply]
Is that some sort of legal situation in the USA? It seems to match the bit of text in the article that says "Lecithin is marketed as a dietary supplement. As such, no claims may be made as to its usefulness in treating or preventing a disease or condition." HiLo48 (talk) 02:49, 16 November 2013 (UTC)[reply]
Yes, as "nutritional supplements" are exempt from regulation by the FDA. StuRat (talk) 03:42, 16 November 2013 (UTC)[reply]
I don't think that's exactly correct. It's a "food" instead of a "drug" and so must comply with food labeling and marketing including special rules for Dietary supplements that's enforced by the FDA (F=Food). Claims about what the food can do is regulated as well but obviously a food group is different than a medication. It cannot claim that it fights disease as that would run afoul of the labeling rules but "cholesterol" is not a disease, rather it's correlated to one. Lowering cholesterol through lecithin, for example, has no known health benefit and another section links lecithin to an increase in TMAO which is also not a disease but linked to one. --DHeyward (talk) 07:24, 16 November 2013 (UTC)[reply]
The OP asks "Is the source good?" I'm particularly keen on the source that says "...the expansion of the soybean crushing and soy oil refining industries in Europe after 1908 led to a problem disposing the increasing amounts of fermenting, foul-smelling sludge. German companies then decided to vacuum dry the sludge, patent the process and sell it as "soybean lecithin." Scientists hired to find some use for the substance cooked up more than a thousand new uses by 1939" I think one must always be cautious about an allegedly good-for-you product derived from someone else's waste product. HiLo48 (talk) 02:47, 16 November 2013 (UTC)[reply]
This sounds similar to the situation with peanuts, which weren't of much value until George Washington Carver experimented with different uses for them, coming up with peanut butter, peanut oil, and a few other products. StuRat (talk) 03:46, 16 November 2013 (UTC)[reply]
Depends on your definition of value - something that goes so well with a beer is of value to me! Equisetum (talk | contributions) 23:03, 18 November 2013 (UTC)[reply]

Hot water improving cleaning ability

It seems that the warmer the water, the better cleaning ability it has -- especially when used in conjunction with soaps and detergents. How/why does water temperature affect cleaning ability? --209.203.125.162 (talk) 19:29, 16 November 2013 (UTC)[reply]

Both the mechanical agitation caused by increasing the heat of the water molecules and any increased rate of reaction of any chemical reactions would improve cleaning and bleaching speeds. μηδείς (talk) 19:48, 16 November 2013 (UTC)[reply]
Solubility of oils, fats etc in water generally increases with temperature. AndyTheGrump (talk) 20:00, 16 November 2013 (UTC)[reply]
Agreed, and edible fats, in particular, tend to be solid at cold water temperatures and liquid at hot water temperatures. Think of the liquid bacon grease poured off from the frying pan, which then solidifies as it cools. Detergents tend to be far more effective in dissolving liquid fats than solid fats (technically emulsifying the fats in water). StuRat (talk) 20:59, 16 November 2013 (UTC)[reply]
How many items of clothing a year do you launder due to their accumulated bacon grease? μηδείς (talk) 21:27, 16 November 2013 (UTC)[reply]
That comment makes me guess that you incorrectly refer to liquid dishwashing detergents as "dish soap" and only think detergents are used for laundry. StuRat (talk) 22:09, 16 November 2013 (UTC) [reply]
Well, no, but I was only thinking about cleaning cloth, not dishes. μηδείς (talk) 03:31, 17 November 2013 (UTC)[reply]
Do you not reckon that you need to wash clothing because of the accumulated sebum arising from skin secretions then? --TammyMoet (talk) 09:38, 17 November 2013 (UTC)[reply]
Not primarily, although I can't speak for others. In any case, sebum is not bacon grease, or at least it doesn't taste like it. μηδείς (talk) 18:44, 17 November 2013 (UTC)[reply]
A Bib (garment) or an Apron might be made of cloth and might to a degree be impregnated with bacon grease. Such items might require washing though understandably they might not be considered "garments". Bus stop (talk) 18:53, 17 November 2013 (UTC)[reply]
So, Stu, you wear a bib regularly? :) 00:43, 18 November 2013 (UTC)

Can I equate "m" from the following two equations?

We get "E/ c^2 = F/ a" after eliminating m from the following two equations.

F = ma & E = mc^2

Which mean F, E, a and c are independent of mass. So is this true if "E/ c^2 = F/ a" is valid equation?162.157.235.1 (talk) 21:45, 16 November 2013 (UTC)EEC[reply]

I'd say normally no, since the m in F = ma is just the mass, while the m in E = mc2 is the mass converted to energy. I suppose there could be some special cases, though, like if a known force applied to an anti-matter particle achieved a measured acceleration, then this was used to determine the particle's mass, which was then converted to energy by ramming it into normal matter (although this would then double the mass converted to energy, so the formula would need to reflect this). StuRat (talk) 21:48, 16 November 2013 (UTC)[reply]
Sure it's valid. Not very interesting, though, since it just says that the ratio of force to acceleration is the object's energy (perhaps rest energy, but the equations are slightly ambiguous; see relativistic mass) divided by the speed of light squared. That's of course just two different statements of mass, so of course they're equal. --Tardis (talk) 00:06, 17 November 2013 (UTC)[reply]
See Relativistic mechanics#Force for the mathematics. To over-simplify a little, F = ma only applies if the mass is constant (which it may not be even in a classical system), and, in a relativistic system, the mass (the "m" in E = mc2) will vary with the velocity, so "m" in the two equations isn't the same. Tevildo (talk) 23:20, 16 November 2013 (UTC)[reply]
No, the "m" in both cases varies, and is the same. As the mass increases at relativistic speeds, the acceleration reduces (as seen by an observer left behind). So the OP's suggested equation is correct, but one must just keep in mind that E is the relativistic energy (rest-mass energy plus kinetic energy). —Quondum 05:02, 17 November 2013 (UTC)[reply]
Yes they are correct, but you are misinterpreting what they mean. E=m (c^2 is a constant) is an identity. They are interchangeable. The total energy (and mass) of an object is the sum of it's rest mass and kinetic energy. Even "massless" particles like photons exhibit gravitational forces equivalent to the E=m identity (energy/mass of a photon is proportional to frequency). As you approach relativistic speeds, the energy division between mass and velocity is observer dependent but the overall energy and gravitational force is not because that does not matter whether it's observed as mass or kinetic energy and the identity will always hold true. The interesting thing is that this applies to everything so a baseball that is thrown has a slightly larger mass when you impart kinetic energy to it. It's tiny but you can use E=mc^2 to find it. --DHeyward (talk) 07:25, 17 November 2013 (UTC)[reply]
Careful — I believe that you end up off by a factor of 2 if you try to use a photon's relativistic mass and Newtonian gravity, even in the weak-field approximation. --Tardis (talk) 00:10, 18 November 2013 (UTC)[reply]
Yes, one has to be a little careful when one starts speaking of the gravitational effects on and by a system: these are not determined solely by the mass of the system. The gravitational influence of a system is determined by the stress–energy tensor, so the pressure contributes. In the case of photons, this additional effect is on the same scale as the effect of the mass. But the gravitational effect does not form part of this question. —Quondum 00:34, 18 November 2013 (UTC)[reply]
First let me point out that even if it made sense to eliminate m from the two equations, that doesn't mean that E, F, and a "independent of mass". The original equations are still valid showing how those things relate to mass. Second point: F=ma isn't a relativistically correct equation. It is a non-relativistic approximation.

Third point: Within that approximation, m stands for rest mass and the E taken from E=mc^2 will be the rest energy. The equation is than correct but is also boring because it adds nothing to the theory and doesn't help solve any problems.


November 17

Biting your tongue

If you bite your tongue or cheek with force, you get a painful area that feels "hard", as if the area swells or something like that. What generally causes this phenomenon (i.e. is it swelling, or something else?), and (if such a term exists) what's the official anatomical/physiological term for an area that's experiencing this phenomenon? Nyttend (talk) 03:23, 17 November 2013 (UTC)[reply]

When most parts of the body are subject to trauma (e.g. biting of the tongue, banging the head, trapping a finger) it is normal for two things to happen. Firstly the body has a reaction which involves extra blood being channeled to the injured area, this assists in bringing materials required to repair the area and the removal of any unwanted products of trauma. The other thing that occurs is bleeding within the soft tissue that is damaged. This causes discoloration, swelling and pain in variable amounts dependent on what and how badly the tissue is damaged. These two processes will cause the swelling you feel, the medical term for hardening of the tissue is induration. Richard Avery (talk) 07:49, 17 November 2013 (UTC)[reply]

Novel electric unicycle design

Does there exist a design for an electric unicycle, where the rider is positioned at the centre of a wheel, rather than atop it; the engine contains no moving parts; and the unicycle is steered by shifting the centre of mass along the axis of rotation? Plasmic Physics (talk) 03:59, 17 November 2013 (UTC)[reply]

I believe you have a monowheel in mind. However, note that there must be moving parts: in your proposed design, even though the center of mass is kept steadily ahead to move it forward, it has to be moving in a circle relative to the outer wheel (as is the rider). (speculation:) Using a weight in this way depends on it being massive in relation to the rider; I suspect it works out to be inefficient to push a weight to where it will move the wheel by force of gravity rather than simply pushing the wheel with the same motor mechanism. Wnt (talk) 04:22, 17 November 2013 (UTC)[reply]
Yes, it is a monowheel I'm thinking of. Plasmic Physics (talk) 05:39, 17 November 2013 (UTC)[reply]
I suppose you could set up a mag-lev connection between the wheel and the compartment where the rider sits. They would still move relative to each other, but there would be no friction (other than air resistance), since the moving parts are not in contact with each other. The rider could then lean forward to move forward or lean backward to move backward. Leaning to the sides should help to steer. StuRat (talk) 05:15, 17 November 2013 (UTC)[reply]
Yes, it is a monowheel that functions on the principle of the linear motor. To ensure that the wheel spins instead of the rider, it could be solved by increasing the difference in the moment of inertia between the wheel and "hub". Plasmic Physics (talk) 05:39, 17 November 2013 (UTC)[reply]
I meant that last sentence as a question, not as statement. Plasmic Physics (talk) 07:52, 17 November 2013 (UTC)[reply]
Yes, the moment of inertia should effect which rotates faster. I also imagine that the battery, motor, etc., would be under the driver's seat, to bring the center of gravity down. This would help prevent him from turning upside down. At high acceleration, though, it might still be a problem. Driver rotation might also occur when braking or if the vehicle hits something. StuRat (talk) 08:41, 18 November 2013 (UTC)[reply]
What if the entire vehicle was structured as a gyroscope? Plasmic Physics (talk) 12:08, 18 November 2013 (UTC)[reply]

Dynamo lights become ever brighter with increasing speed?

I made this circuit to light a couple of LEDs (in series) on my bike. The power comes from a bottle dynamo which I think is rated at 6 V and 3 W. My question is: does the light get ever brighter the faster I cycle or does something limit the output of the dynamo? The LEDs can actually handle at least an amp but I'm a pretty lazy cyclist so I'll never even approach that; I just wondered. If the rating is 3W, that must mean the limit for the dynamo is 500 mA; is that a point at which something inside the dynamo could start to melt? --78.148.107.181 (talk) 16:03, 17 November 2013 (UTC)[reply]

A bicycle dynamo is not, in fact, a dynamo, but a magneto (generator). However, although we have plenty of articles on magnetos, we don't have one which explains how they work. This paper describes the operation of an ignition magneto - a bicycle dynamo doesn't have the contact breaker or secondary winding, but it's more or less the same otherwise, and the Continental paper does imply that the output increases with speed. That being said, I assume that there will be a point where the rotor is continuously saturated and increasing the speed only increases the frequency. The best thing to do is probably just try it, and put in a voltage regulator if the output looks like it's getting too high. Tevildo (talk) 19:50, 17 November 2013 (UTC)[reply]
As speed is increased from zero, the generator voltage will increase proportionately, up to a certain point where the load (the lamps or LEDs) draws a current near the rated output. Beyond that point, two effects come into play that limit the current: a) magnetic saturation of the stator core (Tevildo was on the right track here, but it is the magnets that rotate on the shaft, the windings are on a stator - this avoids needing slip-rings) and, b) pole reluctance. Pole reluctance arises because at high currents the magnetic filed in the stator poles created by the load current opposes the magnet field as the rotor magnet poles rotate into mesh with the stator poles. This effectively lengthens the air gap between the rotor and stator, weakening the generated voltage. The limiting is not a hard or staright line limit - further increase in load or speed will increase the current to a certrain extent. 120.145.133.195 (talk) 00:45, 18 November 2013 (UTC)[reply]
So would it then be approaching an asymptotic limit? 24.23.196.85 (talk) 02:00, 18 November 2013 (UTC)[reply]
The electricity-producing thing on my old bike was called an 'alternator' when I bought it, so presumably it produces alternating current. To drive LEDs, I would consider adding add a rectifier chip and a capacitor to smooth the ripple, and would tip the bike and spin it to make sure it could not overdrive the LEDs and burn them out. Edison (talk) 01:28, 18 November 2013 (UTC)[reply]

Blood glucose result discrepancy

All my fasting glucose tests taken at a medical lab (vein blood) show above 100 mg/dL. However home test (finger prick) results are always ~80 mg/dL, no fasting, before and 1.5 hours after a big meal. How can this be explained? Gil_mo (talk) 16:16, 17 November 2013 (UTC)[reply]

I'm afraid that because this bears on your personal medical issues, an answer would constitute medical advice, which we are not permitted to give. Looie496 (talk) 16:53, 17 November 2013 (UTC)[reply]
I'm asking this on a general note. Let me rephrase: what could be the explanation for such a discrepancy should it occur for anyone doing the test?Gil_mo (talk) 07:10, 18 November 2013 (UTC)[reply]
See Glucose meter, home tests measure whole blood glucose level, lab tests measure plasma glucose level which is generally 10% to 15% higher than the equivalent whole blood value. All the glucose is in the plasma, if you remove the blood cells, the volume decreases but the amount of glucose stays the same, so the amount of glucose per unit of volume rises. Ssscienccce (talk) 11:28, 18 November 2013 (UTC)[reply]
Obvious question, are the home testing strips expired? Have they been stored in an airtight container? Have they been stored in excess heat (like a hot car)? I know these can affect the accuracy. Also, many home testing units contain a little bottle of control solution (with a known glucose concentration) that you can test your strips against. --209.203.125.162 (talk) 18:55, 19 November 2013 (UTC)[reply]

science (magnification in parallel and series circuits)

magnification is independent in series or parallel circuit.true or false? — Preceding unsigned comment added by Mintoooo (talk • contribs) 17:51, 17 November 2013 (UTC)[reply]

The word "magnification" has no meaning for an electrical circuit. If you are going to ask "true or false", you need to use correct terminology. In this case, I can't even figure out what you are trying to ask. Looie496 (talk) 17:57, 17 November 2013 (UTC)[reply]
To paraphrase Chico Marx, then, the correct answer to the question is, "No." ←Baseball Bugs What's up, Doc? carrots→ 18:52, 17 November 2013 (UTC)[reply]
banned editor and off-topic discussion
The following discussion has been closed. Please do not modify it.


It would be nice if people would answer questions only if the question is within their competence. Magnification certainly does have meaning in electical circuits containing inductance (L) and capacitance (C), and is of fundamental importance to radio. It is the basis of tuning. Magnification occurs in parallel L and C circuits - at or near the resonance fequency, the current circulating in the L-C circit may be many times greater that the externally supplied current. This phenomena is referred to as magnification. In a series L-C circuit, the voltage across either L or C at and near resonance may be many times greater than the externally applied voltage - this is also referred to as magnification. The degree of magnification depends on the Quality of the inductor and capacitor. Quality here essentially is degree to which resistance is kept out of the inductor and capacitor. For this reason, various companies in Britain, before British industry lost its way, used to sell instruments known as Circuit Magnification Meters. Marconi being the most well known in the industry (Model TF1245A). In the USA, the various manufacturers (eg Hewlett Packard) called them Q-Meters - this name is easier to say and has become the dominant term world-wide. However the correct term for what happens in resonant circuits is still magnification.
To answer the OP question, magnification is independent in magnitude regardless of the circuit being series or parallel - however what gets magnified, voltage or current, depends on whther the circuit is series or parallel.
Magnification can also occur in circuits containing only resistors and capacitors, and in circuits containing only inductors and resistors. Magnification of either voltage OR current, but not both at the same time, can be arranged by combining current OR voltage in suitable phases. However such circuits are not simple series or parallel arrangements. It can be done becasue the arithmetic sum of voltages in a series RC circuit is greater than the applied voltage, due to differing phase.
120.145.133.195 (talk) 01:00, 18 November 2013 (UTC)[reply]
Ah Wickwack, it's always such a pleasure to have you around. Looie496 (talk) 05:13, 18 November 2013 (UTC)[reply]
Unfortunately, he shouldn't have answered, as this is an obvious homework question with the student making no attempt to solve it on their own. StuRat (talk) 05:19, 18 November 2013 (UTC)[reply]
I am the previous poster 120.145.133.195. It had occurred to me that it might be homework, but it doesn't smell like it. The OP wrote it in quite poor grammar. A question written in a textbook or set by a teacher could well use the term "magnification", but they would not (or should not) word a question as "Magnification independent in series or parallel circuits..." Independent OF what? Independent IN one case and not IN the other?? Quite possibly the OP is a beginning electronics hobbyist or amateur. If so, it was very bad of Looie496 to say that the word magnification had no meaning in electric circuits - rather than helping such a person, it would set them back. That was my reason for posting - to prevent a beginning amatuer from being misled. In any case it's ok to just not answer a homework question, but it is never ok to mislead, intentionally or accidentally. And I am not Wickwack. 58.170.182.209 (talk) 13:38, 18 November 2013 (UTC)[reply]
Ah, then it's an amazing coincidence that you geolocate to Perth and write in the same style as Wickwack, with the same mannerisms. (I do make mistakes sometimes and am willing to acknowledge them, but it is always hard when they are pointed out in such an unpleasant way -- the typical Wickwack style.) Looie496 (talk) 16:17, 18 November 2013 (UTC)[reply]
Probably best to let this lie, but there may indeed be more than one cranky old electrical engineer in the Perth area. I'd imagine their styles and tones could come across rather similarly in this medium ;) SemanticMantis (talk) 18:10, 18 November 2013 (UTC)[reply]
Wickwack and aliases are more known for criticizing other responders for being wrong, regardless of whether he, or the person he criticized, are correct or not. Looie, sorry your pride was hurt. I suggest using this method: "I've never heard of 'magnification' with regard to an electric circuit". This leaves you an out, in case it turns out to be real. And even an expert may not be aware of some obscure terminology used by a small group on the other side of the globe. StuRat (talk) 18:56, 18 November 2013 (UTC)[reply]
I added a useful title. StuRat (talk) 06:03, 18 November 2013 (UTC) [reply]
We have some scant coverage at LC_circuit#Applications, which uses the "magnification" terminology, and mentions the tuning discussed above. SemanticMantis (talk) 18:10, 18 November 2013 (UTC)[reply]
Most likely because the term is most likely and commonly called resonance and specifically electrical resonance. --DHeyward (talk) 05:30, 19 November 2013 (UTC)[reply]
banned editor and focused reply
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Actually, both terms are in use - there is an important difference in meaning. Resonance is what allows magnification to occur. Resonance also causes other phenomena to occur - for instance when a parallel L-C circuit is brought into resonance, a dip (reduction) in the current drawn from the external voltage source occurs, and the phase of the current drawn from the supply is brought into alignment with the supply voltage phase. An analogy is cooking food. Applying heat typically causes several changes - reduction in moisture content, browning, reduction in vitamin content, denaturing of protein, etc. Just as one does not use the term "heating" or "cooking" when one wants to discuss "browning", an electrical engineer does not use the term resonance when he/she means magnification, any more then he/she would say "brought into phase" if he/she meant magnification or resonance. Magnification can be quantified - one can say such-and-such a circuit has a magnification of (say) 96 times. Saying the resonance is 96 times is a nonsence - you can only say things like "off resonance", "near resonant", "resonant" and the like. Further, as I said before, magnification can occur in L-R or C-R circuits, but in these cases there is no resonance in the sense that electrical engineers use the term. 120.145.154.249 (talk) 06:45, 19 November 2013 (UTC)[reply]
Never heard "magnification" used in engineering. "peaking", "resonance", "Q", "Q factor", "FWHM", "magnitude", etc. Never heard of "magnification." Some passive filters can peak, but I've never heard it called magnification. It would be an odd term as I believe the maximum is always referenced as 0db. --DHeyward (talk) 07:12, 19 November 2013 (UTC)[reply]

References: New Approach to the Digital Measurement of Magnification Factor

Marconi TF 1245 circuit magnification Q meter, the instrument identified by the first correct responder

(image) 84.209.89.214 (talk) 22:37, 19 November 2013 (UTC)[reply]

Why “g = GM/d^2” prevail over the higher derivatives of position w.r.t time?

Although higher derivatives of the position are not discussed by the Newton while formulating “F = GMm/d^2” (where reduction in “d” is lopsided for the falling of small objects on earth) but verily the subtle nuances of such spawning can easily be perceived through arcane reasoning if imagined two identical planets of mammoth masses “M” separated by conspicuous on-center distance “d”. Since both masses "M" are under the influence of gravitational force "F" therefore reduction in “d” would be equal but abrupt on either side of point “c” lucidly if “c” is the mid point of “d" as both F = GM^2/d^2 and "g =GM/d^2" are time varying.

The simultaneous abruptness of such motion starts equally on either side of "c" right at the inception of "g" of each M which sent the aforementioned masses “M” swiftly into different higher types of motion such as gravitational jerk, jounce, crackle, pop, lock, drop etc. This means two objects that fall towards each other are under the influence of higher types of gravitational motion/ higher derivatives of position w.r.t time - Theoretically.162.157.235.1 (talk) 23:24, 17 November 2013 (UTC)EEK[reply]

Under Newtonian gravity, there are no higher derivatives of position due to gravity. The acceleration really is a=GM/d^2, and the third, fourth, fifth, etc. derivatives of position are all zero. --Bowlhover (talk) 02:16, 18 November 2013 (UTC)[reply]
Not correct in general. If d is not constant then a is not constant either, so higher derovatives of position such as da/dt are not zero. Only exception I can think of is a circular orbit when the magnitudes of d and a are constant (although even then they are not constant when considered as vectors). Gandalf61 (talk) 10:05, 18 November 2013 (UTC)[reply]

But this hold true only when the difference in two masses is extremely gigantic. For example it is said that both earth and the Newton's apple (smaller objects) accelerate toward each other gravitationally but apple looks a lot to the earth due to its greater acceleration as compared to the earth toward an apple which is so minuscule to be distinguished. Here in this case the on-center distance “d” reduces totally on one side of the mid point of “d” as earth remains at its position (almost) therefore a=GM/d^2 is noticeable but the picture is totally different according to the equation “F = GM^2/d^2” if both the masses are mammoth as illustrated where on-center distance “d” reduces equally on both sides of the mid point of “d” therefore aren’t the said two objects under the influence of type of gravitational motion which is greater than “a=g=GM/d^2”162.157.235.1 (talk) 04:45, 18 November 2013 (UTC)EEK[reply]

The force acting on each object is F=GM^2/d^2. Therefore, by F=Ma (the definition of force), a=GM^2/Md^2 = GM/d^2. Since the acceleration varies with position (and position with time), there will be higher derivatives w.r.t. time, but these just describe how the acceleration changes, it's not correct to say that jerk "prevails over" accelration, instead, each of jerk, acceleration, velocity etc are used to describe how the position of the masses changes. Acceleration just tends to be the most used representation, since higher derivatives tend to be less mathematically useful. Also, in the graviational case, aceleration can always be expressed purely as a function of position, with no initial condition needed for velocity, but higher deivatives will require at least such conditions to be calculated accurately. (da/dt = da/dx . dx/dt = v.da/dx = -2vGM/d^3 in the case where the velocity is parallel to the acceleration). 91.208.124.126 (talk) 09:38, 18 November 2013 (UTC)[reply]

Wouldn't the said both identical masses in scenario collided each other earlier than expected in acceleration?74.200.19.65 (talk) 11:20, 19 November 2013 (UTC)EEK[reply]

November 18

Climate of Korea

My mental image of the Korean War is that of soldiers spending months and months in snow-filled trenches, freezing off half their extremities as they wait for the weather to get warm enough for combat. The climate section of Geography of South Korea would seem to back up my idea, talking about "Winters are usually long, cold, and dry", but the specific data in Climate of Seoul sounds far warmer and more hospitable than my mental image or the picture created by the first article's climate section. What's going on? What's the true situation? Nyttend (talk) 02:35, 18 November 2013 (UTC)[reply]

Well, Seoul is close to the Yellow Sea, and being near a large body of water will tend to warm and moisten things up in winter, if the prevailing wind direction comes in off the water (unless the water freezes over, and I don't think it's far enough north for ocean water to freeze solid there). So, that's my guess as to why it might be warmer than the interior, in winter.
Also, during a war people (both soldiers and refugees) tend to be far more exposed to the environment. So, a temperature which is just fine if you are in a house becomes unbearably cold if you are in a flooded foxhole. StuRat (talk) 04:58, 18 November 2013 (UTC)[reply]
Finally, the cold weather was a major factor in the Battle of Chosin Reservoir, which may have been the images that you were thinking of. Not only is this in the far north of North Korea, close to the border with Manchuria, but the reservoir itself is over 1,200 metres (4,000 feet) above sea level and much of the fighting was on higher peaks and passes. The Environmentallapse rate allows you to calculate a reduction in ambient temperature of 6.49 °C per 1,000 metres of altitude, plus whatever windchill you get in a high mountain pass. Alansplodge (talk) 09:24, 18 November 2013 (UTC)[reply]
BTW, the figures in the climate table that you linked are certainly cold for a climate described as Humid subtropical. The average winter temperatures are lower than Copenhagen for instance. Alansplodge (talk) 11:43, 18 November 2013 (UTC)[reply]
Also, don't forget that the early '50s were at the very end of a short-term global colding trend (which started in the mid-'30s and was at its peak in 1944 -- that was the coldest year of the 20th century), so temperatures worldwide were lower than average. 24.23.196.85 (talk) 07:34, 19 November 2013 (UTC)[reply]

Naming Be
6N
4, additively

Following 2005 inorganic IUPAC additive nomenclature, is the following a correct name for [Be]=N[Be]N([Be]N=[Be])[Be]N=[Be]?

μ3-nitrido-1:1':1"κ3N-tris(μ-nitrido-diberyllium)

Plasmic Physics (talk) 02:41, 18 November 2013 (UTC)[reply]

Wow. This is not my expertise, but there's some coverage of this at [5] but this is... remarkable. So you have a single nitrido (N) bridging three Be-N-Be units (the μ-nitrido-diberyllium). The κ3 indicates the N is linked three times from N (where else?). I suppose the 1:1':1" is a specification of where it links to. But I don't know if the IUPAC rules really require or allow that kind of precision about where a nitrogen is linked from when there's one atom, or so much detail about the three units it links to when it's just tris()... it all seems so absurd. Wnt (talk) 08:46, 18 November 2013 (UTC)[reply]
I'm also using the 2005 Red Book, but I was using IR 9.5.2.1, specifically comments surrounding example 8. Plasmic Physics (talk) 12:00, 18 November 2013 (UTC)[reply]

Please help, Heat transfer coefficient of the external fluid flowing steadily over a horizontal plate

I have read the article "Heat transfer coefficient", only found fluid flowing over horizontal plates (not a plate). Can someone give me an equation on the case of one plate. Many thanks :) SongJie@NTU (talk) 14:23, 18 November 2013 (UTC)[reply]

If you're referring to Heat transfer coefficient#External flow, Horizontal plates, the equations seem to describe a single plate (in four different scenarios), in spite of the section title. If that doesn't meet your needs, could you be clearer about what your needs are? Looie496 (talk) 16:04, 18 November 2013 (UTC)[reply]

How to make adult stem cells totipotent?

Is there a way to make adult stem cells totipotent and therefore provide an alternative non-controversial method of making totipotent stem cells? 164.107.102.191 (talk) 16:48, 18 November 2013 (UTC)[reply]

See our article Induced pluripotent stem cell, and these science articles in Science [6] and Nature [7]. It is not entirely clear to me how these are limited from being "totipotent" (e.g. is there some target cell type that they cannot become?), but maybe someone else can help clear that up. SemanticMantis (talk) 18:02, 18 November 2013 (UTC)[reply]
At least as concerns mammals, pluripotent cells can differentiate to form any cell lineage of the body, whereas totipotent cells can additionally form placental tissues [8]. For most biomedical research applications I would imagine there would be little difference (i.e. if you don't want to study placental tissue it doesn't matter), and in any case human stem cells generated "traditionally" (i.e. human embryonic stem cells) are pluripotent rather than totipotent. Equisetum (talk | contributions) 22:56, 18 November 2013 (UTC)[reply]
Also keep in mind it can just be a matter of evidence. In order to show the cells are truly totipotent you need to actually show them becoming every tissue type; but even making a chimera out of them can leave open a crack of doubt (since the natural cells might take over some fate they fail to adopt). Wnt (talk) 12:32, 20 November 2013 (UTC)[reply]

physics gravittation

In the derivation for gravitational potential energy, we consider the work done by agent in bringing a particle from infinity is a constant for small displacement dx. but once the particle is in the gravitational field, the gravitational force done by an agent will reverse direction. in that case the work done by the agent is first positive and then becomes negative. do we really consider both the positive as well as the negative work? — Preceding unsigned comment added by 120.62.184.196 (talk) 16:56, 18 November 2013 (UTC)[reply]

I don't fully understand your scenario, but if you bring a point into a gravity well close to a planet, you'll get negative work out of it that you can use for kinetic energy, annihilating settlements from space, whatever you'd like. Now if you take it away again, out of the well, do you keep that energy, or do you have to give it back? If you don't count both positive and negative work, does that mean you have a plot of the energy you've extracted/put in that abruptly turns into a flat line at some point? Nature doesn't much like flat lines with sharp corners. So my assumption is that you need to count positive and negative, but depending on exactly what you want to calculate, you might end up defining your number differently. Wnt (talk) 17:14, 18 November 2013 (UTC)[reply]

direction of Jupiter spot rotation

which direction does Jupiter spot rotate?--Akbarmohammadzade (talk) 17:32, 18 November 2013 (UTC)[reply]

Our article is at Great Red Spot, and says "The GRS rotates anticlockwise, with a period of about six Earth days." SemanticMantis (talk) 18:04, 18 November 2013 (UTC)[reply]

Enforced neoteny

As many animals become unsuitable as pets once they reach adolescence, and at the very least need to be castrated/spayed to make them manageable, is there any way to keep them young via drugs ? (Even if such drugs are prohibitively expensive when used for people, they might be offered more cheaply for animals, as many are.) StuRat (talk) 19:45, 18 November 2013 (UTC)[reply]

Do you mean freeze the aging process, or do you mean keep the pets small? 140.254.229.160 (talk) 21:15, 18 November 2013 (UTC)[reply]
You'd be looking at pituitary and genital surgery to remove the source of growth and sex hormones that cause puberty and increase in size. μηδείς (talk) 22:03, 18 November 2013 (UTC)[reply]
That may keep the pets small and infantile, but the pet itself may still age regardless in terms of how the other organs will wear out. 140.254.229.160 (talk) 22:10, 18 November 2013 (UTC)[reply]
I very much doubt Stu is asking about how to keep them young as in not old. Rather, the obvious issue is immature versus mature. Immature primates make good pets. Not so much so after puberty, and the same for most other wild animals. μηδείς (talk) 22:17, 18 November 2013 (UTC)[reply]
Ideally they would stop aging entirely, but I don't believe that's possible. What might be possible, though, is to prevent them from developing adult traits as they age. Yes, neutering them is one method, but I was asking if any drugs are available which can do this, as well. One option might be to prolong their juvenile state, but eventually stop the drugs and allow them to mature naturally. StuRat (talk) 03:48, 19 November 2013 (UTC)[reply]
Failure to develop in size and maturity naturally is caused by the lack of a hormone or a receptor for it. We can then possibly supply the missing hormone (not a missing receptor). But we don't usually give a drug to compete with or block a hormone. Such a thing is entirely possible, but were not at the stage where we can target such drugs to knock out certain types of development without possibly incurring serious, if not lethal side effects. At this point, physical removal of the relevant organs is the only practical option. For example, when my grandfather had terminal stage prostate cancer, they castrated him and put him on estrogen, which competes in some effect with testosterone, but would not entirely have masked it. I suggest looking at treatments for this and breast cancer and testicular cancer as well as acromegaly to see if any chemical treatments have the effect you want. μηδείς (talk) 18:10, 19 November 2013 (UTC)[reply]
Well, we've enforced neoteny through selective breeding of most out our domestic animals. See e.g. Neoteny#Domestication, Origin_of_the_domestic_dog#Neoteny_in_the_rapid_evolution_of_diverse_dog_breeds, Cat#Sociability, and even Self-domestication#Foxes. If there were currently any reliable way to push this trend further via drugs, rest assured that we would be inundated with advertisements for permanent kittens ;) SemanticMantis (talk) 22:32, 18 November 2013 (UTC)[reply]
A boy across the street from me in the 70's was famous for making permanent kittens. Until they stopped buying him replacements. μηδείς (talk) 02:15, 19 November 2013 (UTC)[reply]
Castrati used to be common. Had interesting side effects. Different than eunuch --DHeyward (talk) 07:25, 19 November 2013 (UTC)[reply]

From Chambers 20th Century Dictionary: Eunuch - means a castrated (ie testicles removed) male, especially one castrated before hormonal development; Castrati - means a male castrated before hormonal development and trained to sing. So no difference except that a castrati can sing, but a eunuch wasn't necessarily, and typically was not, trained to sing. So no real difference. 120.145.154.249 (talk) 15:39, 19 November 2013 (UTC) [reply]
OK, I know that this is not the language desk, but please, there is no such thing as "a castrati". --Trovatore (talk) 09:01, 20 November 2013 (UTC)[reply]
There must be, it's in the aforementioned dictionary. 60.228.253.116 (talk) 12:38, 20 November 2013 (UTC)[reply]
What you want is an axolotl, the Peter Pan of the pet world, but not so cuddly. Richard Avery (talk) 15:30, 19 November 2013 (UTC)[reply]
Axolotls can apparently be made to metamorphose into adults by giving them iodine, which is sort of the opposite of what Stu is asking for here ... maybe he'd like a functionally immortal pet Turritopsis_dohrnii ? SemanticMantis (talk) 16:34, 19 November 2013 (UTC)[reply]

November 19

Tea for sore throat

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)[reply]

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)[reply]
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)[reply]
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)[reply]
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) [reply]
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)[reply]
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) [reply]
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)[reply]

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)[reply]

"...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)[reply]
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)[reply]
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)[reply]
I can't definitively answer the OP's question either but I have a clue. In the UK, our equivalent is 'Simple Linctus.' [9] 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 [10]. 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)[reply]

Could a dog sense radon or the the effects of radon in a basement?

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)[reply]

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.
SteveBaker (talk) 16:31, 19 November 2013 (UTC)[reply]
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)[reply]
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)[reply]
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)[reply]
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)[reply]
"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. [11][12] 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)[reply]

&*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)[reply]

"Cyclone Cleopatra"

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)[reply]

Sort of quasi-cyclones -- see Medicane. Looie496 (talk) 17:28, 19 November 2013 (UTC)[reply]
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)[reply]
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)[reply]
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)[reply]

3D printed stainless steel?

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)[reply]

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)[reply]
(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)[reply]

Tank duel revisited

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)[reply]

We don't do speculation here. SteveBaker (talk) 00:15, 20 November 2013 (UTC)[reply]
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)[reply]
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)[reply]
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)[reply]
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)[reply]

November 20

Unsure how to calculate a percentage of power to create a solution

Note: I have blanked this thread, as it is clearly a request for medical advice. We do not answer such questions. Seek such advice from a qualified medical professional. AndyTheGrump (talk) 03:40, 20 November 2013 (UTC)[reply]
This blanking is being discussed on the RD talk-page. Please leave it blanked pending that discussion. Many of you are beyond 3RR and WP:CIVIL and will be blocked if this behavior continues. DMacks (talk) 04:47, 20 November 2013 (UTC)[reply]

halting global warming?

I've looked and I can't find the answer to this question (two parts):

  1. If all (or essentially all) of the electricity was produced by means that don't burn fossil fuels, would that be enough to halt global warming?
  2. If not, what if all (or essentially all) automobiles didn't burn fossil fuel - would that be enough? Bubba73 You talkin' to me? 06:20, 20 November 2013 (UTC)[reply]
There are also other sources of atmospheric greenhouse gases, like slash-and-burn agriculture. And things like solar panels may not be a solution at all, if it takes more energy to produce them than you get out of them over their lifetime, and this energy comes from burning fossil fuels. StuRat (talk) 07:24, 20 November 2013 (UTC)[reply]

Effects of masturbation on sperm count.

What effect does masturbation have on sperm count and the ability to have children? 94.124.154.253 (talk) 07:47, 20 November 2013 (UTC)[reply]

According to Masturbation#Evolutionary utility, masturbation can increase the ability to have children, by flushing stale sperm with low motility out of the male's genital tract, making way for fresher sperm with higher motility. Red Act (talk) 08:15, 20 November 2013 (UTC)[reply]
Cool! Thanks for that! This non-signed-in user can continue his self-pleasuring habit, safe in the knowledge that it is all in the interests of protecting his progeny. 94.124.154.253 (talk) 08:29, 20 November 2013 (UTC)[reply]

Why doesn't water vapor always condense in water droplets?

Water will evaporate because the energy is distributed evenly in the water, and as a result some water molecules near the surface will have enough energy to escape the liquid. The water vapor that forms will eventually be at room temperature though. So if the water vapor is below its boiling point, why doesn't the vapor condense into water droplets? Why does it take a certain concentration of water vapor for droplets to form? 74.15.137.253 (talk) 13:08, 20 November 2013 (UTC)[reply]

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