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November 28

Most viewed health topics on Wikipedia

I recently read in a news article that Wikipedia allows free access to its data on the most frequently searched topics. As I understand it, this information can also be broken down according to language (but not to geographical location).

If this is the case, I would like to know which health topics are most commonly viewed on Wikipedia in both English and Arabic. A list of up to about 2,000 topics in each language would be ideal, but otherwise I would settle for a shorter list!

Alternatively, if it’s not possible to stratify according to health topics specifically, I would also be interested in the same lists in a similar category (e.g. medicine, science, biology, etc). — Preceding unsigned comment added by 14.203.101.110 (talk) 00:39, 28 November 2014 (UTC)[reply]

The main portal for page stats is http://stats.grok.se/ Which will let you look up individual pages or download count files for all requests. There is a top list but it doesn't seem to have been updated in several months and shows some spurious requests (probably due to bots and other automated web processes). The most visited pages on a month to month basis are often typical issues that are being highlighted in the news (e.g. new movies, celebrities, wars, etc.) As far as medicine goes, I suspect that the Ebola related pages have rated very highly in recent months. As far as I know, there are no preexisting subcategorized lists of page views for medicine or any other topic. In principle one could be created though, either by hand, or by selecting a subset of pages that are already labeled with categories associated with medicine. That would presumably take someone with a bit of programming skill however. Dragons flight (talk) 01:24, 28 November 2014 (UTC)[reply]

See Category:Lists of popular pages by WikiProject.

—Wavelength (talk) 03:11, 28 November 2014 (UTC)[reply]

You may also want WP:5000; it only gives results per week, not long-term, but since most health topics generally don't get a ton of spikes from news coverage, you'll be able to make a decent guess on "most popular" by checking a few weeks' entries. If you have a bot or a way to scrape content, you can easily amalgamate statistics by months or years. Nyttend (talk) 03:58, 28 November 2014 (UTC)[reply]

Using Wavelength's link, you can see a list of the 1000 most popular WikiProject Medicine pages at Wikipedia:WikiProject Medicine/Popular pages. John M Baker (talk) 15:35, 28 November 2014 (UTC)[reply]

What's the thickness of a clothing to prevent mosquito bites?

I want to visit South America, and I want to protect myself from mosquito bites. How thick should a clothing be to prevent the piercing of a southern american mosquito? What is the minimum thickness? How deep can southern american mosquitoes pierce into the human skin? 173.33.183.141 (talk) 03:31, 28 November 2014 (UTC)[reply]

I don't think it's primarily a question of thickness, but more of the quality and density of the weave. I've never experienced mosquitos biting through a normal dress shirt, but I'd be less sure about a t-shirt, even if technically thicker. If you want to be sure, use something like DEET or Icaridin on the skin and Permethrin on clothing and mosquito nets. Famous brands here in Germany are NoBite and Autan, but international branding seems to vary a lot. --Stephan Schulz (talk) 03:48, 28 November 2014 (UTC)[reply]

Thanks. Do southern american mosquitos have longer piercing heads than the north american mosquitos? 173.33.183.141 (talk) 21:30, 29 November 2014 (UTC)[reply]

Sublimation and temperature change

Take a quantity of water and evaporate some of it, and the rest cools to an extent. Take a quantity of ice and sublimate some of it; will the rest become colder? Nyttend (talk) 19:25, 28 November 2014 (UTC)[reply]

Yes, the ice becomes colder. It is this same phenomena which is used to cool spacesuits. That is why NASA came to over-look the presence of water on the moon during the Apollo era. The H2O that the NASA scientists found in the moon samples, they concluded was just man-made contamination. However, the Soviets knew but the Americans never read their science papers.--Aspro (talk) 20:18, 28 November 2014 (UTC)[reply]

Function generator design

Function generators are usualy designed with the primary waveform generated being a triangle wave created by charging a capacitor with a constant current. At higher frequencies than about 3-5 MHz, however, the comparator used has to be very fast and the triangle wave distorted to operate the comparator as fast as possible. I was wondering if there were any function generator designs that used a square wave produced by a voltage controlled oscillator as the primary waveform. Triangles can then be produced by integrators and sine by shaping the triangle as usual. Are ther any problems with this approach and are there any manufacturers using this technique especially for fast (20MHz) generators?--86.157.138.192 (talk) 19:32, 28 November 2014 (UTC)[reply]

That might have been true 40 years ago, but any modern function generator will be purely digital, using a DAC to create the waveforms. Apart from the audiophile market (which is more art than engineering), there's very little analog equipment for use at low frequencies available these days. However, I'm sure it would be possible to design an analog function generator along those lines, it just wouldn't be a commercially viable proposition. Tevildo (talk) 21:13, 28 November 2014 (UTC)[reply]

20MHz triangle and sine from a DAC??--86.157.138.192 (talk) 21:22, 28 November 2014 (UTC)[reply]

120 MHz! It's amazing what they can do these days ("these days" starting in about 1995). Tevildo (talk) 21:42, 28 November 2014 (UTC)[reply]

Indeed! Our article is direct digital synthesis. And if you have unlimited budget, you can get direct digital synthesizers deep into microwave bands - arbitrary digital waveform synthesis at tens and hundreds of gigahertz! Such devices are used for satellite communication and microwave RADAR design and test.

But we don't even have to look into wacky aerospace and defense technologies to find such circuitry! Chances are high that you've got one of these K-band digital synthesizers - or one like it - built into your home computer!

Nimur (talk) 00:04, 29 November 2014 (UTC)[reply]

Universe - universe = 0?

If our universe was created from nothing, and we dont seem to have found much antimatter so far, is it possible that an anti universe was created at the same time as the matter universe? --86.157.138.192 (talk) 21:35, 28 November 2014 (UTC)[reply]

But if there was nothing ("0") befor, what created or caused the universe? The theory of an antiuniverse is scientificly as bad (not proven) as the famouse Bigbang theory. Some astrophysists still belive in the theory that this universe has simply always been here. --Kharon (talk) 01:55, 29 November 2014 (UTC)[reply]

Mathematically, that notion doesn't work. ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:03, 29 November 2014 (UTC)[reply]

In fact, the idea that the universe "has always been there", strikes me as the cosmic equivalent of the "Turtles all the way down" story. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:32, 29 November 2014 (UTC)[reply]

Well, as explained in the antimatter article, the idea is apparently not totally dead even that antimatter could exist in large amounts somewhere in our observable universe. It is also possible that the observable universe encompasses a large region that is entirely matter, but that there is a variation on a larger scale even than the entire universe we see, so that other regions may be mixed or entirely antimatter (which isn't far from the OP's suggestion really, except the two were once connected as a single region of space but now "you can't get there from here" due to cosmic inflation). But CP violation in baryogenesis is still the more likely looking answer, since there are observed deviations. Wnt (talk) 04:52, 29 November 2014 (UTC)[reply]

The concept of a zero-energy universe does not depend on equal amounts of matter and antimatter. -- ToE 16:51, 29 November 2014 (UTC)[reply]

Question About the Elimination of Energy

Since energy can be neither created nor destroyed therefore does Einstein’s energy equation equitable with any other forms of energy such as P.E, K.E, Work Done….....?162.157.249.151 (talk) 22:22, 28 November 2014 (UTC)eek[reply]

Yes. However, while Einestein's equation says that the total energy of a system remains constant, it does not say that it cannot be converted into other forms of energy. Potential energy is frequently converted into kinetic energy (dropping objects, burning fuel, electrical discharge, etc.) and vice versa. Is this what you are asking? --T H F S W (T · C · E) 23:27, 28 November 2014 (UTC)[reply]

By equating, I meant eliminate energy E from E=mc^2 and any other equation of energy of any form. Although physicists don’t agree but here is the example if units are interchangeable in dimensional analyses of the following?

1- Energy, E= mc^2 ----- Eq. (A)

2- E = mv^2 --------Eq. (B) as if “Joule is equal to the energy transferred (or work done) when applying a force of one newton through a distance of one meter (1 newton meter or N·m:)” - [ Wikipedia]. Since, joule = N.m = [(Kg.m)/sec^2].m = Kg.m^2/sec^2 therefore this means Energy; E = mv^2 as L/T is the unit of velocity. We get mv^2 = mc^2 after eliminating “E” from Eq. (A) and (B) and hence v=c unless unit of energy is defined differently in relativity and classical physics

Since you mentioned conversion therefore would the energy released from the burning of 1kg mass (nearly =1lit) of gasoline be = mc^2162.157.249.151 (talk) 04:39, 30 November 2014 (UTC)eek[reply]

The answer to your last sentence is "no", because only a very small portion of the mass of gasoline is converted to energy. The combustion products also have mass, which is almost identical to the original mass of the gasoline and oxygen. In nuclear reactions, a much larger portion of the mass is converted to energy, and the decay products have lower mass than the parent product, but even complete radioactive decay of a kilogram of plutonium, for example, will yield much less than 9*10^16J of energy.--Wikimedes (talk) 11:04, 30 November 2014 (UTC)[reply]

Ok thankx, I thought E would be different upon changing the mass in e=mc^2. 162.157.249.151 (talk) 16:05, 30 November 2014 (UTC)eek[reply]

E=mc^2 can be used to calculate the energy released when mass is converted to energy. In the case of burning gasoline, most of the mass is instead converted to another form of mass (water and carbon dioxide), so the energy released is more easily calculated directly from calorimetry. (A freshman or high school chemistry book might be more useful for understanding basic calorimetry of combustion than the Wikipedia article). E=mc^2 is used to calculate energy released in nuclear reactions, but the mass entered into the equation is not the starting mass, but the difference between the starting and ending mass. In a matter-antimatter reaction, all the mass can be converted to energy, and the use of E=mc^2 is more easily applied.--Wikimedes (talk) 01:58, 1 December 2014 (UTC)[reply]

NMR basic problem

I have a relatively basic NMR question, but I am having trouble figuring it out. The chemical formula is C5H10O. The chemical shifts are 1.3 (singlet, integration 2 cm), 1.9 (singlet, integration .3 cm), 5.0 (doublet, .2 cm), 5.2 (doublet, .2 cm), 6.0 (doublet of doublets, .2 cm). The problem also says the peak at 1.9 ppm is solvent and concentration dependent. Does this mean it is -OH? I know there is a C=O. The spin spin splitting is throwing me off. — Preceding unsigned comment added by Pinterc (talk • contribs) 22:34, 28 November 2014 (UTC)[reply]

Do you know if that's the molecular formula, or the empirical formula? That is, do you know if the molecular weight is ~86, or could the compound be something like C₁₀H₂₀O₂ or C₁₅H₃₀O₃? (Getting mass spectroscopy results greatly helps NMR determination.) You may want to also double-check your integrations. As written, they sum to 2.9, meaning that each proton should account for ~0.3 (assuming 10 protons) - which means you're getting something like a 6:1:1:1:1 ratio, and a fair amount of error on integration amounts. (Although if you're using an empirical formula, you might be running 30 protons, with possibly more like a 20:2:4:2:2 or 21:2:3:2:2 ratio.) But if the "2 cm" is a typo for "0.2 cm", then you're summing to 1.1, and getting more of a 2:2:2:2:2 ratio. All this, of course, is complicated by the solvent and concentration dependance of the 1.9ppm peak. You may want to figure out what about the peak is concentration/solvent dependent: is it just chemical shift, just integration, or both? You're pretty saturated, though, so that's going to limit you. Do work it out yourself, but I think the carbonyl requirement is going to take up your unsaturation allotment. The splitting pattern itself isn't too hard to accommodate. (You have to remember that if a proton is split, it's going to be splitting another proton in turn, so that constrains how the doublet of doublets and the two doublets are related to each other. Do you have the J values for the coupling constants? In this example it's probably going to be uninteresting, but matching the J values of the coupling constants can be used to figure out which proton is splitting which other proton.) The concern I might have about the split peaks is their shift - ca. 5 ppm and a general lack of unsaturation in the molecule implies some sort of relationship to the oxygen(s). You also have quite a small number of peaks in comparison to the number of protons (especially for larger multiples of an empirical formula) - that usually (but not always) implies a high degree of symmetry in your molecule. -- One suggestion I would make is to break the problem into parts: list a bunch of different molecular fragments which can account for different portions of the data at hand. Then see if you can come up with a way to merging those fragments together to account for all the data. -- 160.129.138.186 (talk) 00:03, 29 November 2014 (UTC)[reply]

There's already some confusing idea if C5H10O is the actual molecular formula: the proposed C=O is the oxygen atom, so there's no other oxygen left to be the OH oxygen. DMacks (talk) 05:10, 29 November 2014 (UTC)[reply]

Per NMR spectroscopy, "Coupling to additional spins will lead to further splittings of each component of the multiplet e.g. coupling to two different spin ½ nuclei with significantly different coupling constants will lead to a doublet of doublets." This alone implies a CH - CHR - CH structure. I don't see a good table at chemical shift; we should have something like [1]. I fooled around with this for a bit and couldn't think of any ideas; [2] is a useful link but I'm stumped. Someone ought to be able to recommend some searchable NMR database that might come through here. Wnt (talk) 01:47, 29 November 2014 (UTC)[reply]

Chemical shift is the general idea, not specifically 1H. For information specific to that, see Proton NMR. But the table there is confusing as hell...seems entirely focused on "what else is attached to the C with the H", making it hard to identify the aldehyde structure as such and except for that case omitting all other H that are not on sp³ C (no vinyl or aryl or OH or NH themselves, just the C_α to it). DMacks (talk) 05:18, 29 November 2014 (UTC)[reply]

You've also got 5 peaks, which implies 5 unique carbons. What are the splitting constants? You can sometimes match neighboring bits by matching splitting constants... --Jayron32 13:32, 29 November 2014 (UTC)[reply]

Hmmm, I'd hoped someone would clarify the issues with the problem ... the last I looked at this my closest guess was CC1=CC(O)C=C1, which on the prediction site above gives the right doublet of doublets and two doublets and a peak at 1.9 from the methyl... the problem was, it has one doublet too high and the peak at 5.2 is a doublet of doublets and the 1.3 peak is absent, not to mention it's missing two hydrogens. Wnt (talk) 17:29, 1 December 2014 (UTC)[reply]

There can only be one degree of unsaturation, because C5H10 is only 2 hydrogens short of the saturated alkane (C5H12, or pentane). That means you can't have 2 double bonds. --Jayron32 19:09, 1 December 2014 (UTC)[reply]

Yes, but try to come up with a model that involves only singlets, doublets, and doublets of doublets... Wnt (talk) 03:05, 2 December 2014 (UTC)[reply]

November 29

What are the chances of getting hpv from oral sex?

What are the chances of catching the hpv virus for men performing oral sex on women. And, once you do get exposed, what's the risk of getting oral cancer?Whereismylunch (talk) 04:28, 29 November 2014 (UTC) ″[reply]

Fairly sure the answer will depend on factors like whether any form of barrier protection was used, the sex of the recepient, and whether you're referring to the risk to the receiving or giving/performing partner. Also the presence or absence of open sores or wounds on the mouth of the performing partner, the number of times and whether the people involved have HPV or at high risk of it (e.g. sex workers). The difficulty of seperating these means some figures will be averages of them (for example, I don't think anyone is going to try to come up with a figures for a person who's received oral sex 1x, 2x, 3x, 4x.... during their lives), but I don't think anyone is going to come up with a random single figure for the risk of getting HPV from oral sex. Nil Einne (talk) 13:36, 29 November 2014 (UTC)[reply]

But on wikipedia they have a random single figure for aids from anal sex.Whereismylunch (talk) 18:11, 29 November 2014 (UTC)[reply]

The question is not from receiving, but from giving oral sex, and I think we can just assume average numbers, not specific risk factors. Basically, the OP seems to be asking, of those who get oral cancer, how many can attribute it to a sexually transmitted HPV infection, not "what are my odds of getting oral cancer if I service a guy wearing a condom", which we wouldn't answer anyway. That being said, my understanding is the risk is measurable, but I have no Idea where I read that, so I am not about to venture a guess. I suspect I read it somewhere that was advocating that not only girls get the HPV vaccine. μηδείς (talk) 03:23, 30 November 2014 (UTC)[reply]

Where was it stated it was from receiving not giving oral sex? It wasn't even stated the sex of the receiving partner. And so average numbers for what? I don't get the relevance of most of your later stuff. The point is that the OP hasn't sufficiently defined what they're asking for this to be answered in any meaningful way. (Note also as stated below there are multiple subtypes of HPV and I'm not sure these are always considered together.) In terms of your middle point, this [3] easily found from a simple search says "every year, over 9,000 men are affected by cancers caused by HPV". This includes those affecting "the anus, mouth/throat (oropharyngeal cancer), and penis". I'm sure you could come up with a value for those only affecting the mouth/throat. However it would be silly to assume the HPV always came from sexual contact, and even more flawed to assume that the sexual contact was from giving oral sex. Nil Einne (talk) 04:05, 30 November 2014 (UTC)[reply]

I mistook this thread for the almost identical one that had just archived. μηδείς (talk) 22:14, 1 December 2014 (UTC)[reply]

Your question is not specific enough. It is better to ask, what are the chances of acquiring a HPV infection of subtype N by the person giving oral sex from the person receiving oral sex provided that the latter person has an active HPV infection with subtype N? The chances are probably high—in the range of tens of percent. However the vast majority of such infection are asymptomatic and will resolve on their own in a few months. Only a very small fraction will become chronic and potentially cancerogenic and only of subtype 16. Ruslik_Zero 03:40, 30 November 2014 (UTC)[reply]

If I WP:AGF you are correct, then that should be fixed ASAP. It makes zero sense for any article on wikipedia to say that. For starters, while many people with HIV will eventually get AIDS, it's complicated and can take a while. For this reason, it's far better to talk about the chance of getting HIV not the chance of getting AIDS and few, if any, will talk about the chance of getting AIDS.

Secondly, nearly every single source will differentiate between the receiving or receptive partner and performing or insertive partner when it comes to the risk, as these can vary quite significantly.

Thirdly, the sex of the receiving receiving partner probably may not have a significant effect on the risk for anal sex in the generalised case. In the real world it may have an effect because the person may have a different risk profile and other factors. But actually this would apply to the giving partner in the oral sex case which I didn't mention because I was going to mention the later issues. (In "anal sex" practices where the insertive/giving partner is female like pegging, these normally aren't considered when it comes to anal sex. And female/male here refers to the sexual organs of simple cases. For intersex and other individuals where the partner may have a penis despite being female, I didn't mention that complexity.) In the oral sex case, it's quite important that we differentiate between fellatio and cunnilingus, both are which quite correctly and commonly described as oral sex yet are likely to have difference risk profiles, hence why I said the sex of the receiving partner is significant. (To be fair, anilingus]] may also be included which would include both sexes and isn't something I really mentioned.)

Since I can't find what you referred to (may be it's already been removed), I'll give a current example. Our HIV/AIDS#Sexual has risks. But it does differentiate between receptive and insertive partner. (And receptive is quite a large range.) It also assumes no barrier protection (condoms) were used. It's also referring to an average per act risk, and exposure to an infected source. And if you read the text, it gives further complications such as whether it's a low or high income country, and the presence of other STIs, and whether commercial sex work including prostitution is involved. This is an example of the complexity involved and why the article you referred to which gave a single figure probably should be changed. Note our article also mentions a value for oral sex (again differentating between receptive and insertive) but makes it clear it's referring to cases where the insertive partner is male. (The high/low income thing is interesting and not something I was aware of although I guess not surprising. Since we're talking about cases where condoms weren't used and the partner has HIV, these obviously aren't the reason. I would guess it's because of how well the HIV is controlled, the relative health of both partners, the number of conurrent STIs, perhaps also stuff like the usage of and type of lubrication and a bunch of other factors.)

Nil Einne (talk) 04:05, 30 November 2014 (UTC)[reply]

I will re formulate my question and make it clearer. Just forget what I asked. What are the chances of catching the hpv virus from giving oral sex for men to someone who is infected? I already googled it yesterday and it said in one study it was less than 10 per 1000 person months for healthy men. — Preceding unsigned comment added by Whereismylunch (talk • contribs) 22:00, 30 November 2014 (UTC) Men giving it to women, not men giving it to men.Whereismylunch (talk) 22:07, 30 November 2014 (UTC)[reply]

Hydrogen roasting

Molybdenum and tungsten is produced by roasting the oxides under hydrogen gas. What makes the ore of one metal better qualified over the ore of another? Which ores were this technique first applied to, for the purpose of refining the metals? Plasmic Physics (talk) 09:13, 29 November 2014 (UTC)[reply]

Metals are smelted from ore using the chemical process of reduction. The material used as a reducing agent depends on the electronegativity of the metal. Some metals (like the ones in your example) have very low electronegativity and require extreme conditions to accomplish ore extraction, such as protecting the entire process within a reducing atmosphere. Mihaister (talk) 07:19, 30 November 2014 (UTC)[reply]

Metals are normally smelted, but not always. In hydrogen roasting, hydrogen plays the role of the primary reducing agent, not just the reducing atmosphere. The key difference between smelting and roasting, is that smelting involves a molten phase at some point in the process, whereas roasting does not. An example would be the hydrogen roasting of chalcocite:

Cu
₂S + H
₂ → Cu + H
₂S

Plasmic Physics (talk) 07:42, 30 November 2014 (UTC)[reply]

I stand corrected. Mihaister (talk) 07:51, 1 December 2014 (UTC)[reply]

If you mean What makes the ore of one metal better qualified over the ore of another – for roasting as opposed to smelting. It would be the melting point of the metal (and to some extent I suppose, the ticklish problem of removing unwanted other elements that occur in the ore, if refining was attempted in the molten state). After all, what would one line the crucible with to stop the crucible from melting? Even ZrO2 Ceramic Properties only go up to 2400°C!!! --Aspro (talk) 02:23, 1 December 2014 (UTC)[reply]

OK, thanks. How was the process historically applied? I'm after some light trivia to write into an article where this process is somewhat important in explaining the main topic. Plasmic Physics (talk) 02:32, 1 December 2014 (UTC)[reply]

In that case you have come to the right place - I specialize in trivia - whatever its mass happens to be. Have a read of [4] Chapter One, page 1 & [5] page 143. As I vaguely recalled, it appears that the ore needs to be chemically purified before roasting. --Aspro (talk) 06:43, 1 December 2014 (UTC)[reply]

Red Bull Stratos

The person might have been burned during re-entry. But he did not. But spacecrafts get fire during re-entry. Please explain why? --IEditEncyclopedia (talk) 10:39, 29 November 2014 (UTC)[reply]

See Aerodynamic heating. The guy probably got warm from the friction, but he wasn't going fast enough to cause combustion. The typical "shooting star" comes into the atmosphere at a very high speed and burns quickly. Speed seems to be the key issue. ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:27, 29 November 2014 (UTC)[reply]

Also, try this: Rub your hands together very fast... Do they get warm? That's why things get hot on re-entry. Friction causes objects to heat up, the faster something is "rubbing" against something else, the more heat is generated. An object such as a meteor or a space craft is moving very fast indeed, and as such, generates a lot of friction with the air of the earth's atmosphere. --Jayron32 13:28, 29 November 2014 (UTC)[reply]

Friction is too much of an over simplification when it comes to de-orbiting craft and lumps of comic rock. At these velocities the air stops moving before it gets to the leading surface (called something like the stagnation point). So low flow, low friction! The bulk of the heating comes from compression in this case. The temperature of this air at this point (when it has been turned to plasma) is enough to vaporize all known materials. Fortunately it is not in direct contact with the heat shield (because there is no flow) and so most of the thermal energy radiates away. At lower speeds, the air conducts away much of the heat caused by friction alone, because it is in contact and thus convention is the main method of heat transport. --Aspro (talk) 14:53, 29 November 2014 (UTC)[reply]

An important point (not mentioned yet) is that the intrepid Mr Baumgartner only _fell_ to Earth, he was never in orbit. A spacecraft in orbit will be moving much more quickly on re-entry than one which has just been launched straight up, so there's much more energy to dissipate in atmospheric heating on reentry. Tevildo (talk) 15:17, 29 November 2014 (UTC)[reply]

Absolutely! That's the huge difference between the two examples. For skydiving from orbit (via an emergency, one man, inflatable reentry device), see MOOSE.-- ToE 16:46, 29 November 2014 (UTC)[reply]

I agree. The free fall from a high altitude balloon is much slower than typical orbital speeds. For a somewhat analogous situation see also space elevator. Mihaister (talk) 23:22, 29 November 2014 (UTC)[reply]

It's not about the height you fall from - it's about the speed you were travelling when you started to fall.

When you start off at zero speed, you accelerate until you reach "terminal velocity", at which point the force due to the pressure of the air equals the force of gravity, and you stop going any faster. As the air gets progressively denser, your terminal velocity gradually decreases, and at no point are you going fast enough to produce significant problems. That's also why SpaceShipOne was able to get back to Earth without the need to heat-resistant tiles or an ablative heat shield. In the Baumgartner jump, the fastest speed he ever reached was around 850 mph.

When you start off in low-earth-orbit, you're initially moving at between 15,000 and 18,000 mile per hour...when you reach the atmosphere, you're already moving vastly faster than terminal velocity...and you are going so fast that you're reaching the denser air before you've shed enough speed.

Looked at another way, the amount of kinetic energy you have to burn off to reach the ground at a safe speed from orbit is phenomenal. Kinetic energy is proportional to the SQUARE of the speed...so not only is an orbital craft moving twenty times faster than Felix Baumgartner did - but the amount of energy needing to be shed (per kilogram of mass) was 400 times greater.

In terms of how that energy gets turned into heat, it's a bit complicated because some of the energy goes into heating up the object itself, and some into heating the air around it...and playing with the shape of the craft, the angle of re-entry, the nature of it's surfaces, makes it possible to dissipate most of the energy into the air rather than into the craft itself...but regardless of that, it's clear that there is so much more energy to get rid of when you fall from orbital speeds than if you fell from the same height but without being in orbit.

SteveBaker (talk) 14:54, 2 December 2014 (UTC)[reply]

Snow-resistant buildings

How can buildings be constructed to be able to support four meters of snow without being damaged?

New York's Cuomo warns snow-hit Buffalo of risk to roofs—Reuters (November 24, 2014)

—Wavelength (talk) 17:32, 29 November 2014 (UTC) and 19:10, 29 November 2014 (UTC)[reply]

Use a steeper roof pitch. Plasmic Physics (talk) 21:36, 29 November 2014 (UTC)[reply]

How steep would it have to be to avoid all snow accumulation ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:30, 29 November 2014 (UTC)[reply]

Houses built in Northern latitudes typically have steep roofs for this exact purpose. This image is from the main article on roofs. Mihaister (talk) 23:30, 29 November 2014 (UTC)[reply]

Perhaps the section heading is misleading. My question is about buildings actually supporting an accumulation of four meters of snow on their roofs, and not about techniques for deliberately avoiding snow accumulation.
—Wavelength (talk) 00:28, 30 November 2014 (UTC)[reply]

In snow-bound areas, the solution to building damage from snow accumulation is to build structures where snow does not accumulate. If the snow crushes your roof in, the more sensible problem is to build a roof to allow the snow to slide off, rather than to accumulate. Does that mean that sometimes people in such areas sometimes build structures in an unintelligent way, so that the snow builds up and then caves in the roof? Yes, they do. But the best solution is to avoid letting snow accumulate in the first place. You can build structures to support the weight of the snow, After all, if you can build a bridge to support multi-ton trucks rumbling across them all day, you can apply the same principles to support multiple tons of anything, including snow. Any structure that will support the weight will support the weight. The question is whether such structures are economically sensible, or whether it just makes more sense to pitch your roof so snow doesn't gather. --Jayron32 01:49, 30 November 2014 (UTC)[reply]

Just add extra dead load of the said snow while designing the slab thickness if the structure is RCC.162.157.249.151 (talk) 03:54, 30 November 2014 (UTC)EEK[reply]

Some of those roofs in the picture don't look very snow resistant. Specifically, the ones that are attached to their neighbours. The snow would accumulate in the valleys and cause a leak problem at thaw time. Richard Avery (talk) 07:50, 30 November 2014 (UTC)[reply]

I don't think your concerns are really a problem. Those valleys are supported by load bearing walls and there are clearly visible drainspouts to handle the meltwater. The picture shows a good design for adjoining buildings to handle heavy snow.

I can't really speak for houses, but warehouses and other buildings with large roof areas may simply opt for large support structures that can take the weight. When I toured a DC facility in Owen Sound, for example, there were these thick steel support structures, much larger than anything I'd seen elsewhere for the size of the roof they supported. They weren't visible from the outside, but inside they gave the place something of the appearance of an enormous ribcage. They're not much different than normal columns and OWSJ, just much more robust. Matt Deres (talk) 13:22, 30 November 2014 (UTC)[reply]

The method we use here in Finland is that the occupant buys a shovel. 88.112.50.121 (talk) 16:28, 30 November 2014 (UTC)[reply]

Yes, that works well when there are upwards of five feet of snow on the roof. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:59, 30 November 2014 (UTC)[reply]

It does work, although one would usually not let it get that thick, especially if it is older packed heavy snow. Shoveling a roof is easier than shoveling a similar amount from a driveway, as gravity helps a lot. 88.112.50.121 (talk) 17:20, 30 November 2014 (UTC)[reply]

When you get several feet in the space of a few hours, as with Buffalo recently, it's pretty hard to avoid the problem. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:58, 30 November 2014 (UTC)[reply]

New snow is pretty light and fluffy, I've never seen a real world problem with it. People have lived here in Finland for 10,000 winters, and the best technology we have for snow on the roof is a shovel. If you come up with a better solution, please do tell. Maybe we can share patent income! Basing all architecture on highly sloped roofs -- thanks but no thanks. 88.112.50.121 (talk) 20:49, 30 November 2014 (UTC)[reply]

Read what happened in Buffalo recently. And by the way, there is such a thing as a roof shovel, i.e. a scraper with a very long handle. But the citizens of Buffalo were overwhelmed by it all, and there many reports of collapsed roofs. That's probably what triggered the question here. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:51, 30 November 2014 (UTC)[reply]

Just reporting how people who deal with the issue every year handle it, sir. 88.112.50.121 (talk) 00:03, 1 December 2014 (UTC)[reply]

Helsinki gets 72 cm of snow a year - Buffalo gets 240 cm on average but in this storm got nearby Cowlesville got 223 cm in 3 days. Rmhermen (talk) 03:49, 1 December 2014 (UTC)[reply]

So I suggest getting a shovel and getting busy with it. The alternative of suddenly re-architechting all your buildings to have steep pointy roofs is ...yeah, well, good luck with that.

It is funny to see people struggling with a simple perfectly natural thing. Like someone who discovers he needs to mow his grass, or that dead leaves need to be raked. Memo to all: you got to shovel your snow! 88.112.50.121 (talk) 05:36, 1 December 2014 (UTC)[reply]

It seems that it isn't unheard of to have snow guards/snow barriers (and it's a legal requirement in some cases) on roofs in Finland to protect people under the roof from excessive falling snow & make sure the snow accumulates in a safe fashion with respect to the load bearing structures [6] [7] [8] and perhaps also to keep a minimum level of snow for insulation (per our article).

Not from Finland but as an alternative to shoveling [9]. (Although I'm not denying that shoveling is the most common method, albeit sometimes with assitance particularly for commercial buildings File:Snow removed from roof Keljo.jpg File:Snow removed from roof Keljo closeup.jpg & Commons:Category:Snow removal from roofs.)

That said, I think Rmhermen, BB et al do have a point that it's flawed to automatically assume there's something wrong just because people and structures are able to deal with something in one area when it causes greater problems in another area, particularly without considering how similar the situation actually is, the frequency of such events or how out of the ordinary it is, and the reasons such differences in the way things are dealt with might exist. In particular, most places have problems dealing with extremely rare events, I doubt Finland is any different.

Also e.g. [10] [11] (many of the articles relate to snow on roofs) or even our article snow removal has some info on snow on roofs.

It's not like roofs have never collapsed in Finland [12] or there isn't such concern [13]. In fact [14] is designed to provide warnings for when shovelling is necessary and appears to have been developed in Finland [15]. (Although more limited similar ideas may exist [16] [17].)

And there are other risks besides the roof collapsing, as the presence of snow guards illustrate [18] [19] [20]. The shovelling itself obviously caries some risks [21] [22] (the video is from Estonia but the uploader appears to be from Finland). This Finnish person [23] seems to understand that albeit in relation to a different case.

Nil Einne (talk) 13:02, 1 December 2014 (UTC)[reply]

Another factor to remember is insulating the ceiling or roof. If the roof gets warm, the snow sticks to it more, and ice forms more. If the roof stays cold, the snow slides off more easily.122.108.177.30 (talk) 07:15, 1 December 2014 (UTC)[reply]

Actually, it's the opposite. If the snow disappears from the roof sooner than it does for your neighbors with similar roof styles, it means your house is improperly insulated - too much heat is escaping through the roof. ←Baseball Bugs ^{What's up, Doc?} carrots→ 14:13, 1 December 2014 (UTC)[reply]

Can you mix ants of the same species but of different ant colonies?

If you pick ants from one ant colony and place them in a totally distinct (but of the same species) ant colony, would they come well along? --Senteni (talk) 19:15, 29 November 2014 (UTC)[reply]

There has been considerable research on this topic. A Google Scholar search for 'ant colony recognition' will provide a starting point. [24] Ants communicate via scent (notably pheromones), and it seems that each colony (or possibly supercolony [25]) has a distinct scent. AndyTheGrump (talk) 20:30, 29 November 2014 (UTC)[reply]

Indeed, but the tolerances and differentiation vary amongst species and this may be a factor in which species form supercolonies and the degree of genetic uniformity within and between separate colonies. Further, there are some parasitic species who will intrude upon a closely-related colony and exist as a distinct genetic population within it without producing their own workers, and in these cases the parasitic species seems to be exploiting the fact that the pheromones employed are (apparently) innately known and universally recognized by the host species. But still other parasitic species will exploit the fact that some species have colonies that establish a scent that falls within certain constraints but varies from population to population, a scent that individuals are fine-tuned to recognize in development and which is therefore in a sense "learned" by the resulting superorganism; parasitic species in this context will sometimes attempt to install their own queen before the first broods are born, in order to either cohabitate with the, to completely leverage their work for themselves, or to simply leave the host colony disorganized until the physical burrows can be captured by a working population developed from their own offspring.

To answer the OP's question more directly and succinctly: in rare instances, yes -- one could integrate a migrant ant -- but not in most cases.Snow talk 02:16, 30 November 2014 (UTC)[reply]

Two examples: I was told by an entomology professor that an individual worker pharoah ant could be flown from NYC to LA (or Tokyo, etc) and could rejoin a colony there. Also the Argentine ant is thought to be so invasive in the USA because of a founder effect, wherein all invasions are related because they came from the same few queens. So, in their natural range they have small colonies that fight eachother, while in their introduced range different colonies aren't sensed as rivals, and giant supercolonies form. It all really depends on the specific species and how they sense kin/colony relationships. SemanticMantis (talk) 15:44, 30 November 2014 (UTC)[reply]

That is a fascinating aspect of the Argentine ant that I actually had forgotten about, but which perfectly demonstrates how divergent genetic variation and population size can be for the same species in different ecological niches. The Argentine ant proved so successful as an invasive species on several continents that one particular closely-interrelated (if massive) genetic population grew to encompass huge range of territory consisting of vast numbers of genetically similar individuals and colonies, while it stayed (relatively) constrained in it's orignal and more localized South American habitat, where it co-existed with other more closely-related and similarly capable subspecies and species, and other competitors/constraining species that it had co-evolved with. In other words, it might just as easily have been another similar population with most of the same traits but whom would be sharing their own unique phenotype for pheromones and leveraging their vast numbers to out-compete both the native species and any other Argentine subspecies/close relatives who might otherwise migrate. Snow talk 14:30, 1 December 2014 (UTC)[reply]

Ants also detect colony mates via signatures of hydrocarbons on the cuticle (which are different from pheremones). Some species will attack a con-colonial worker if she is washed off by humans. SemanticMantis (talk) 16:09, 30 November 2014 (UTC)[reply]

I had meant to mention as well that there are other types of chemoreceptors utilized by ants for communication and navigation. Although at the same time, ants are amongst the the very few organisms in which the role of pheromones is not overstated in popular science reporting; most all species of ant rely on them to some varying (but generally very significant) degree that is often well-documented; whereas the pheromones used, or purported to be used, in countless other species (vertebrate and invertebrate) are often overstated and/or not particularly well understood. Snow talk 14:30, 1 December 2014 (UTC)[reply]

November 30

Human/Animal Crossbreeds

So, you can cross a horse and a donkey to make an ass or a mule, and a lion and tiger to make a liger, or a dolphin and a false killer whale to make a wolphin. Could humans theoretically mate with orangutans or chimpanzees and produce offspring? Would the offspring be viable? Horatio Snickers (talk) 20:31, 30 November 2014 (UTC)[reply]

For starters, we do have some info in our article on humanzee. ---Sluzzelin talk 20:36, 30 November 2014 (UTC)[reply]

Here are various facts and theories about how our very great-grandparents may or may not have bred with Neanderthals, Denisovans and their ilk. So there's a glimmer of hope for a chimpboy, but if it were already possible, we'd already have at least enough for a case study in a medical journal somewhere. Humans have been getting halfway there for a long time. InedibleHulk (talk) 23:17, November 30, 2014 (UTC)

Reminds me of when AIDS was first gaining major publicity and it was alleged to have originated in apes. Frank Zappa said, "Why I want to know is, who's screwing those monkeys?" ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:27, 30 November 2014 (UTC)[reply]

If this subject disturbs you, do not swim with seals or dolphins. In any case, most reports of humanzees are just the unfortunate sufferers of Gandler-Kreukheim Syndrome. μηδείς (talk) 03:08, 1 December 2014 (UTC)[reply]

As we have an article on Next (novel) perhaps this malady is eligible to be added to List of fictional diseases.--Aspro (talk) 03:35, 1 December 2014 (UTC)[reply]

It should almost certainly be possible to produce a chimera (honestly, I'd thought that by now some interpersonal squabble at an in vitro fertilization clinic would have gotten out of control and led to this...). I don't expect the hybridization to be easy or else we would know about it; what being hard means is that one guy trying it in 1919 is not proof it could never work. In theory, of course, with enough effort (a gene by gene germline replacement trial, conducted over countless generations) someone could surely make it work, but there's a vast chasm between the preposterous amount of resources that implies and the reality that so few people even attempt it. Wnt (talk) 09:43, 2 December 2014 (UTC)[reply]

A chimera is not a hybrid. It is basically a random blend of cells that can look like a note sent by a serial killer with letters cut out of random publications. Look at this chimera between two different genera of mice, and note the assymmetry of the eyes, to say the least. In a civilized society you'd be looking at ostracism, defrocking, and all sorts of civil and criminal abuse charges if you did such a thing. μηδείς (talk) 17:55, 2 December 2014 (UTC)[reply]

Orgasm Weapon (serious)

A few years ago I was looking at weapons or brain waves or electromagnetic radiation articles (something of that nature) and I found an article stating that a potential item exists that could cause females to orgasm from a distance. I am familiar with search operators and advanced search techniques but I can't seem to find the article. Please help. Thanks. Judasschwarz (talk) 22:45, 30 November 2014 (UTC)[reply]

Sounds like the plot line of Flesh Gordon. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:47, 30 November 2014 (UTC)[reply]

Is this the only response I'll get? — Preceding unsigned comment added by Judasschwarz (talk • contribs) 22:53, 30 November 2014 (UTC)[reply]

What have you found in Google so far? ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:01, 30 November 2014 (UTC)[reply]

A lot of stuff related to porn and a movie title "Orgasmo". I've also used Google to search Wikipedia articles containing terms weapons, electromagnetic, sonic, microwave, directed, energy, orgasm, non-lethal along with the - parameter to remove useless links. I wish I could use "intext" exclusively so that pages with a term in the title (orgasm in this instance) wouldn't come up. I don't know if that's possible or how to do that though.Judasschwarz (talk) 23:09, 30 November 2014 (UTC) edit- combined those search terms in various combinations.[reply]

You can do a "-intitle:orgasm" (no quotes). You'll need a separate one for the plural. InedibleHulk (talk) 23:20, November 30, 2014 (UTC)

Thanks I'm looking now with that parameter. I've also considered using The Wayback Machine. I have some experience using it but haven't used it to perform this sort of advanced searching. — Preceding unsigned comment added by Judasschwarz (talk • contribs) 23:54, 30 November 2014 (UTC)[reply]

It was the key plot point in Orgazmo. That alone doesn't necessarily mean it's also not real, but it makes it feel that way. InedibleHulk (talk) 23:04, November 30, 2014 (UTC)

A quick Google search on "neurological orgasm weapon" brings up (a) lots of pages (mainly written in primary colours on a black background in ALL CAPS) by people who claim to be victims of them, and (b) references to this 2008 paper (see, for example, this article from the Guardian). The name Robert Galbraith Heath is also a common feature. Make of this what you will. Tevildo (talk) 00:05, 1 December 2014 (UTC)[reply]

Thanks. — Preceding unsigned comment added by Judasschwarz (talk • contribs) 00:13, 1 December 2014 (UTC)[reply]

Also is this: "(mainly written in primary colours on a black background in ALL CAPS)" a clue to something? I don't understand what that statement was added for. — Preceding unsigned comment added by Judasschwarz (talk • contribs) 00:17, 1 December 2014 (UTC)[reply]

Well, that sort of website design is very common among people with unorthodox views of the world. I was just noting that people who believe they have been attacked by the CIA with "neurological weapons" - an unorthodox view by most standards - seem to follow this pattern. Tevildo (talk) 00:55, 1 December 2014 (UTC)[reply]

It is a tale told by an idiot, full of sound and fury signifying nothing. At least that's what I grabbed from the hint. Using all-caps is GENERALLY CONSIDERED SHOUTING LIKE A MADMAN!!! And colourful text can uncomfortably distracting. If someone showed up on your doorstep, like a Mormon dressed in a silly pink and white costume with a purportedly true message about orgasms, it's natural to feel skeptical. Same applies to the web. Wikipedia is where it is because we dress the part. (That link was merely at the top for "black white blue suit". Any similarity to Jimmy Wales is a purely eerie coincidence.) InedibleHulk (talk) 01:00, December 1, 2014 (UTC)

Lol, understood. — Preceding unsigned comment added by Judasschwarz (talk • contribs) 01:04, 1 December 2014 (UTC)[reply]

The concept exists in science fiction, certainly—in Larry Niven's Known Space books, such a device is called a tasp. (Niven's books also present a wired, non-remote version called a droud.) Direct electrical stimulation of the pleasure centers of the brain is portrayed as potently habit-forming; addicts are sometimes called wireheads. The latter article, interestingly, provides some real-life examples of such stimulation (under controlled conditions); it seems to be just as attractive as science fiction suspected. As far as I know, there is no extant technology for carrying out such stimulation remotely and noninvasively. TenOfAllTrades(talk) 01:19, 1 December 2014 (UTC)[reply]

No fair, I was just going to say Tasp. Niven also invented flash crowds. μηδείς (talk) 01:40, 1 December 2014 (UTC)[reply]

And one of those stories contains the phrase "a stack of TVs, big ones almost an inch thick." —Tamfang (talk) 08:07, 1 December 2014 (UTC)[reply]

That reminds me, it was also in at least one softcore space porn. Can't remember if it was Femalien, Emmanuelle in Space, Andromina: The Pleasure Planet, Veronica 2030 or Femalien II. Pretty sure it wasn't Sex Files: Alien Erotica, but might have been Alien Sex Files 3: Aliens Gone Wild. I'd had enough of the genre by the time that one came out. InedibleHulk (talk) 03:04, December 1, 2014 (UTC)

Are you think of that whore-er movie Barbarella in the Ogasmatron? Whilst on the subject. A beam of photons shone through crystalline carbon can have a funny effect on some people from quite a distance. Just a five carat stone in a jewellers window with a sign announcing Sale Now On is effective along a whole boulevard if the sun shines upon it.--Aspro (talk) 04:02, 1 December 2014 (UTC)[reply]

No, it wasn't that. Definitely later 90s, during the Baby Blue Movies res-erection (absolutely no pun intended) or Fridays Without Borders. Almost certain it was Emmanuelle in Space, but which one? Haven't seen Handful of Diamonds, but the pub scene sounds gripping. InedibleHulk (talk) 12:29, December 2, 2014 (UTC)

I'd be immensely surprised if any amount of searching turns up even a hint of serious research in terms of a device that could trigger an orgasm at a distance. For one thing, the mechanisms necessary for inducing the neurochemical changes implicit in such a feat would have to be so complex and so specifically targeted that, aside from being well beyond our current understanding, by the time you developed this technology you'd almost certainly already have the capability to incapacitate someone through means that would certainly be more practical for a weapon (by causing them to go unconscious, driving them into an agitated state, inducing intense pain or disrupting their senses or their ability to think clearly, all of which would be much easier to achieve -- and all of which, come to think of it, have been studied in recent times as possible avenues for a weapon that acts upon the brain at a distance). The only possible "advantage" a weapon that specifically induced and orgasm might offer over these approaches as a weapon would be a (reprehensibly) psychological one, in much the same way rape is sometimes employed in war to demoralize and humiliate.

Putting aside that piece of science-fiction, utilizing chemical aphrodisiacs is a tactic that has been considered by modern states a number of times, as several vague concepts or plans were hatched (but to the best of my knowledge never pursued very far) in which a laced water supply or aerosol would be employed, with an assault to coincide with the resulting love-in. It's just as well -- I mean, it might seem like the most horrific example, but would still almost certainly qualify as a chemical attack forbidden by modern international law and indeed one that could lead to significant health concerns for those involved, be it from physical reactions to the chemical itself, STD's, psychological impact and the possibility of resulting rape (again, the factor of a "love" weapon that goes under-considered).

To add yet another Sci-fi reference to those noted by others above, the last two books written by Frank Herbert for his Dune saga include a sexual weapon that comes in the form of women who are capable of enslaving huge populations of men with their wiles. For me it was one of the very few places in those otherwise absolutely genius books where I felt like the kind of social/psychological weapons that are common to the work jumped the shark just a bit. And of course a man ultimately defeats their capabilities by being even more of a sexual dynamo... Snow talk 23:16, 1 December 2014 (UTC)[reply]

Niven came up with the chemical aphrodisiacs as well, in his Ringworld series, especially the vampire people. μηδείς (talk) 02:13, 2 December 2014 (UTC)[reply]

I did add a tad of detail to "orgasmatron" non-fiction usage in 2008, but that certainly isn't ranged. Still, it invites a theoretical suggestion that some very strong electromagnetic stimulation might have related effect. Also, some artists I wouldn't want within a hundred miles of me claim to have done it with infrasound.^[26] Still, biology is variable ... I'm sure that if you survey enough women you'll find one who can achieve genuine orgasm purely by watching a Taylor Kitsch movie. :) Wnt (talk) 09:22, 2 December 2014 (UTC)[reply]

During the cold war, Wright Laboratory produced a series of short papers on highly unconventional weapons. One of those (to pick an example close to this one) was the infamous Gay bomb which was supposed to cause (male) enemy troops to suddenly turn gay and start hitting on each other after being sprayed with female pheremones from a chemical weapon of some kind - the idea being that they'd be effectively incapacitated and unable to fight! These (often horribly politically incorrect) ideas were almost never carried beyond those very short paper studies - and they seem to be wildly unlikely to work. However, some of them did get funded, experimentally (consider Project MKUltra that attempted to use LSD as a mind-control drug - or the Convair NB-36H nuclear-powered aircraft that actually flew over Fort Worth, Texas with an unshielded nuclear reactor aboard!). So if it ever existed (and I could find no evidence of that), it's highly likely that your idea was amongst those cold-war concept weapons. Lots of crazy things were dreamed up during the cold war - the research laboratories had more or less unlimited funding and minimal government oversight - so they tended to fund small think-tanks to put up ideas like this. In light of how recently that kind of "crazy" blue-sky thinking had revolutionized warfare by producing the atom bomb - you can see what it wasn't a bad idea to do that. So they'd have a bunch of smart people meet in a conference room once in a while and be instructed to list whatever comes to mind without constraints of any kind (practical, moral, financial, scientific or otherwise). The cost to do that is utterly negligible - and the potential reward could be something as ground-breaking at the Manhatten Project. However, when they turned those meetings into brief summary documents - and those are eventually declassified - you get a document that appears to be saying that the US government did research into making men turn gay...which couldn't be further from the truth. SteveBaker (talk) 14:31, 2 December 2014 (UTC)[reply]

December 1

How scientific is economics?

I recently asked an economics question here, and it was moved to the humanities desk. I thought that was odd. I can't see how economics could tell us anything useful if it doesn't follow the scientific method. Is economics a science?--79.97.222.210 (talk) 01:42, 1 December 2014 (UTC)[reply]

It depends on who you ask. Our article, definitions of economics, cites several famous historians and economists who use "science" in the definition of economics. The article also cites several textbooks and reviews that categorize economics among other sciences. The very same article lists many more reputable sources who do not use "science" in the definition.

Most accredited universities do not administer the department of economics alongside physical sciences. Some universities administer economics departments alongside the mathematics department. Many universities jointly administer their departments of art and science, blurring the distinction. So, at least among academic circles, there is room for debate about how things should be categorized.

Economics can be approached using the scientific method. This approach is applied less universally to economics than, say, to physics or chemistry.

For the purposes of the Wikipedia:Reference desk, our present categorization places economics within the scope of WP:RDH. This is consistent with the Dewey Decimal System and the Library of Congress Classification: both systems place Economics between Law and Politics, and quite distant from the "Science" category.

Nimur (talk) 02:54, 1 December 2014 (UTC)[reply]

I tend to think of economics as a bit of both. In a closed system where currency is based on the value of bullion and there is no borrowings or interest, then it is simple mathematics. As soon as Kings (and later) politicians started to debase the coinage (inflation) and invented new financial tools such as credit/debt, etc., and used these tools to buy popularity, wage war, stimulate the fishing industry to ensure a ready supply of seafarers for the navy to recruit in time of crisis (referring here to Queen Elisabeth I ) things got more complicated and less reality based. Now, Economists (with a capital E) just make it up as they go. Then they try and find reasons why they think they are right and why they think everybody else is wrong. So, today it has become an open dynamic system that is too complicated to model with any certainty. Since as soon as the model gets updated and refined, it is already out of date.--Aspro (talk) 02:57, 1 December 2014 (UTC)[reply]

Economics is a social science. Social sciences indeed are sciences, since they employ the scientific method, but when topics are classified (classification = when you put each thing in one basket, and it can't go in more than one) for practical purposes, the social sciences are generally put with the humanities and not with the sciences. This is apparently because of what the social sciences and the humanities study — they're not the same of course, but in general, they're a lot closer to each other than either one is to the hard sciences. If you have different baskets for English literature and chemistry and you're trying to decide which basket gets economics, you'll probably put it with English literature simply because the subjects are a lot more similar: they deal with different aspects of the human experience (neither one would be around without humans), while chemistry is independent of humans, and human biology (being just the human branch of zoology) would be about the same if we didn't have enough intelligence to study human biology. There are still some difficulties (psychology deals with human behavior and the biology of the brain, so where does it go; archaeology is a kind of anthropology, a social science, but it relies heavily on geology and other hard sciences; and is history in the social sciences or the humanities), which you can see reflected in how JSTOR divides its journals by subject, so sometimes we simply have to be a little arbitrary. Nyttend (talk) 04:29, 1 December 2014 (UTC)[reply]

Social sciences in general (and economics in particular) is generally characterized by the extreme difficulty in creating and running controlled, reproducible experiments. Economics may make a prediction (factor X will produce economic result Y under conditions Z), but then how does one run a controlled experiment which produces reliable results? You can't create carefully controlled human experiments which can be run over and over and which can reliably produce identical results. That's part of the problem with classifying economics as a science, and why "social sciences" in general get classified with humanities and not other hard sciences. If I want to run an experiment on, say, the way a spring reacts to forces, I can run the experiment as much as I want, get scrupulously reliable results, and then use those results to make predictions about other springs which I can have faith will work as predicted based on past results. Social sciences isn't able to do that. At best we can make rough predictions based on historical results, but conditions are NEVER identical, and forecasts for that reason are quite fuzzy, and only marginally better than dumb luck. --Jayron32 12:25, 1 December 2014 (UTC)[reply]

Hmmm, I find I'm often the one usually calling the assertions particular social sciences (or particular research in the social sciences) as speculative and not supported by altogether rigorous empirical practice, rather than defending them as I'm about to, but I do feel you've gone to a bit of an extreme in how you've described them here. There are in fact many, many spheres of the social sciences that are quite to respectable side of "hard" science, with perfectly reproducible methods, such as the cognitive sciences (though granted they are based as much in physical/biological phenomena as social), psychology, and certain areas of linguistics, to mention just the three of the areas that most stand out to me. Not that reproducibility is even considered an absolute feature of all good work done in the "hard" sciences, much of which relies on modelling and other theoretical work that cannot be immediately tested or wherein a large margin of variation with current testing methodology and technology is initially expected; failure to understand the role of such modelling can sometimes lead to very poor understanding of the modern application of the scientific method with regards to modelling, with sometimes problematic consequences. Furthermore, not even the most rigorous physical science exists in a state of absolute reproducibility, and most all experimental science inhabits various areas on the spectrum of statistical inference. Consider also that human beings often vary as much in their "purely" biological make-up as they do with regards to psychological responses, but I've never seen epidemiology called out as "soft" science for it's reliance on data which covers huge variances amongst individuals.

As someone who comes both from a background of the hard (biological) sciences and one involving those fields which neatly straddle physical and social phenomena (cognitive science, linguistics, and sensory perception studies), and who firmly believes that the latter have, through the cleverness and insight of good researchers in their approach to methodology, attained basically the same level of empirical integrity as the former, I will say that in my experience, most academics and researchers inhabiting this middle area have an a pretty robust respect for economics as one of those fields in the social sciences which has made some fairly strong predictions on behaviour that seem to have been born out consistently by evidence. There are a few reasons for this, but three stand out as particularly relevant in making results stable and predictable. First, at least as regards macroeconomics, the population sizes and datasets can be quite massive, which is obviously always quite desirable when attempting to control for variation and confounding factors. Second, behaviours in economics, as indeed with all kinds of psychological phenomena, are not perfectly random amongst humans; point in fact, modern understanding of the human mind continues to show us again and again how hard-wired the brain can be to approaching certain problems and how universally (or near universally) individuals respond to certain situations, sometimes even when logical analysis shows that universal trait to be a behaviour which, intuitively at least, is quite irrational and problematic (see Game theory and Decision theory, for example). And third, economists favour approaches to prediction which are based largely on mathematical models suggested by the data rather than making sweeping assumptions about the state of mind of the participants, which is often an area they speculate on only after their statistical analysis of that which was known absolutely to have happened -- or which they wisely avoid altogether. This is a very, very different approach from such social sciences as sociology and cultural anthropology, which often do form complex (and dare I say it, convoluted, speculative, and impressionistic) theories which either make empirically questionable assumptions or else don't really provide a lot of concrete information in terms of clear and scientifically valid mechanisms that increase our knowledge of the phenomena studied in a significant way.

In short, and as regards which fields and which particular areas of research exist where on the spectrum of hard to soft science, the social sciences are not nearly all created equal and suggesting as much betrays a significant misconception of how some of these fields operate and present their evidence. Indeed, some of them have more rigorous standards of proof than many theoretical areas of the physical sciences that most would not dream of calling soft. Neither A) the statement that social sciences are altogether lacking in reproducibility or firm, clearly delineated and testable assumptions, nor B) the assertion that reproducibility is an absolute feature of all insightful science take into account the complexities of modern research in these areas. I certainly understand the kind of soft (or as you put it, "fuzzy") research you were trying to reference -- I often find myself rolling my eyes at work at the extremely soft ends of these fields too; as much of my undergrad work was in linguistics, I had to take many a sociology course which I'd just as soon avoided and by the end I think I would have pulled my hair out by the roots if I'd had to read one more "theory" that utilized the overly-wrought idiolect that predominates in that field to try to hide the fact that the author wasn't actually making any kind of insight but rather using convoluted prose to imply some kind of significant new way of looking at an issue without actually genuinely informing on it any significantly empirical way. But all of that said, you way, way overstated the argument and threw into the same bag massive bodies of good science and huge traditions of empirically valid research, in a way which I do not feel is remotely factually representative of those fields. Beware of over-generalization with regard to subjects of such massively far-reaching implications; it's not very scientific. :P And certainly as regards economics in particular, at least as concerns researchers utilizing quantifiable data it is absolutely a science of applied mathematics and statistics -- I don't even know what other broad handle for human endeavors you could reasonable use to describe it, if not calling it a science. It's only where this avenue of inquiry intersects with politics, ideology and policy-making that the term refers to a less empirical pursuit, and that's honestly true of any number of other fields. In other words, this can be described as a philosophy of economics and this is clearly an application of economics as a science (regardless of how accurate you view the findings of either). Snow talk 21:44, 1 December 2014 (UTC)[reply]

It is getting more scientific and can produce reasonable results. However a lot of the people involved have political ideas that override any scientific detachment or don't understand about motives except for greed and poverty. I think there is still quite a bit of truth in the old joke about the difference between philosophy and economics. In one they ask a different question each year and expect the same answer, for the other they ask the same question each year and expect a different answer. ;-) Dmcq (talk) 13:05, 1 December 2014 (UTC)[reply]

The hard science use of Wikipedia

What is the use of Wikipedia as a whole in the context of hard science?

I don't understand the justification of time spent here by intelligent people whom are desperately needed in our society in so many other areas.

I see no logic in purpose as an open and accurate knowledge database of humanity, as noble as founding intent may have been. While much open history of discussion exists and is quite telling for the individual with the time and drive to search through it, there remains a power structure and ability to delete certain data, which always invites corruption and bias at some level.

If someone has a clue, or "theory", please let me know.2601:8:8F00:CA:55CA:998D:E18C:7BC0 (talk) 03:29, 1 December 2014 (UTC)[reply]

Are you asking if it's a good use of effort to be maintaining coverage of hard-science topics here? Many of our science experts are professional scientists who edit here in their spare time; if they want to relax by writing about their professional specialties, more power to them. It's the same in other fields, both scientific and not; Doc James is a doctor who writes a lot about medicine (see his biographical article for information relevant to your answer), Arthur Rubin is a mathematician who has written a good deal about mathematical topics (again, see his biography), and Acroterion (there's no article about him) is an architect who writes a lot about architecture. Nyttend (talk) 04:18, 1 December 2014 (UTC)[reply]

Err. How do think we the intelligent people (your words not mine) got to be so, if it wasn't for the previous generation of intelligent people taking time out from other worthy pursuits to pass their knowledge and wisdom on to us. Education and access to knowledge is now an essential part of 'our' societal needs. Is that rational not justification enough. Don't you think progress of human-kind would stagnate, if new advancements in technology (like papyrus then paper for writing, printing presses, correspondence courses which took advantage of a reliable postal system, etc., etc.) were ignored? As for a power structure and ability to delete certain data. This has always been the case. Even back when knowledge was passed on by oral tradition only, individuals probable edited out and added stuff to satisfy their on whims and fancies.--Aspro (talk) 04:23, 1 December 2014 (UTC)[reply]

Access to information is a key required for development. Yes Wikipedia is not perfect but it is 1) the best we have for a freely accessible general overview 2) is very extensively read Doc James (talk · contribs · email) 04:25, 1 December 2014 (UTC)[reply]

Hm. Perhaps Theory X and Theory Y might be an interesting article for you. Lots of people like to be useful. Dmcq (talk) 12:54, 1 December 2014 (UTC)[reply]

Meaning of endorse and endorsement in psychiatry

What is the meaning of endorse and endorsement in the following context: "Significance of Endorsement of Psychotic Symptoms by US Latinos. In US regional studies, Latinos frequently endorse psychotic symptoms associated with impairment and mental health service use, yet do not meet criteria for psychotic disorder." I did check endorsement but it didn't help much... Thank you! Lova Falk talk 13:29, 1 December 2014 (UTC)[reply]

From a "Handbook of Psychology" - 'report or endorse symptoms' [27]. Here is another fairly random article from a psychiatry journal that uses "endorse" to basically mean "report" [28]. The first link is the best I've come up with for a ref that defines the usage, but it does seem very common, search "endorse symptom" on google or google scholar for many similar examples. This is not the definition given by this (not terribly high quality) medical dictionary: [29]. SemanticMantis (talk) 15:10, 1 December 2014 (UTC)[reply]

December 2

why is it cold at the north and south poles of the earth?

why is it cold at the north and south poles of the earth?Whereismylunch (talk) 00:36, 2 December 2014 (UTC)[reply]

Because the sun doesn't shine as strongly there as it does at the equator. See our article on seasons for some detail. If the north pole faced the sun, it would be much hotter than the equator, and the south pole would be even colder because it would never see sunshine. Dbfirs 00:41, 2 December 2014 (UTC)[reply]

I think you mean rather to say that if the Earth's rotational axis was directly parallel to the plane upon which its orbit lays, such that if the North Pole pointed directly towards the sun, then it would result in the situation you describe. Point in fact, the North Pole does face the sun sometimes and gets just as much average sunlight, adjusting for cloud cover and other climatological factors, as any other point. In fact, during half the year it gets more sunlight than the equator. The differences in temperature have more to do with the timing and consistency of this radiation and the way temperature is dispersed along the Earth's surface, and with the fact that snow reflects a good deal of that radiation, than it does with the amount of light that actually falls on a particular patch over the course of the year. Snow talk 01:20, 2 December 2014 (UTC)[reply]

It actually never gets more sunlight (in terms of total energy) than the equator. It gets more hours of sunlight for a good portion of the year, but the light it gets is dimmer because the light always strikes at an oblique angle. Sit in a dark room and aim a flashlight directly at the table. You see a bright circle. At the same distance, if you tip the light at an angle, you find that the brightness of the circle dims considerably. The light from the sun strikes the poles at an angle, even at the solstice the angle is pretty pronounced, so even when the north pole is leaning towards the sun, it is still receiving less total light than the equator is on any given day. It's the angle the light strikes at, more than anything else, which determines the average temperatures of the various latitudes. --Jayron32 01:37, 2 December 2014 (UTC)[reply]

You're part right. Averaged over a year, the poles receive about half as much total energy as the equator. That difference is the main reason the poles are much colder than the equator. However, there are days (such as the solstices) when the poles actually receive more total energy per day than the equator. [30] Dragons flight (talk) 01:57, 2 December 2014 (UTC)[reply]

Thanks for that link. I stand corrected. --Jayron32 02:03, 2 December 2014 (UTC)[reply]

Yes, good caveat -- absolutely, obliquity influences the overall amount of photons that strike a given surface point on the Earth, or any body in relation to a light source. For the starting purposes of the OP I was most interested that he first receive a correct and proper visualization as to the relative alignment of the astral bodies in question, which is what I meant to be correcting there. But I suppose I should have said that any given point gets an even given surface point of the Earth gets a roughly equal amount of exposure to the sun, as opposed to an identical amount of sunlight. Of course, even that isn't exactly perfectly accurate, owing to variations in surface topography. Snow talk 02:22, 2 December 2014 (UTC)[reply]

I should have said averaged over the year, the poles get less than half the total amount of sunshine (insolation) that the equator gets. The sun is never as strong (rate of transfer of heat) at the poles as it is at the equator. Dbfirs 08:14, 2 December 2014 (UTC)[reply]

I once read somewhere or other (I have heaps of sources just as reliable!) that if the axial tilt were more than 54° then the poles would be warmer than the equator. I never got around to trying the math on that one. —Tamfang (talk) 09:28, 2 December 2014 (UTC)[reply]

There are some good illustrations and relevant info at insolation. SemanticMantis (talk) 17:34, 2 December 2014 (UTC)[reply]

Yes, there's a formula that should prove Tamfang's claim, but the problem with applying just the formula is that a change in axial tilt would dramatically and unpredictably change the airflow and cloud cover, so a much more complex model would be needed to make accurate predictions about polar temperatures. Dbfirs 19:05, 2 December 2014 (UTC)[reply]

Phenylketonuria and Obesity

Because PEA is made via Decarboxilation of L-Phenyalaline, I guess that PKU Patients have somewhat lower levels of Phenylethylamine... Now, because this Neuromodulator is associated with some forms of Appetite regulation (especially "Emotional appetite"), do you find it logical to assume that PKU subjects will have a slightly bigger chance for being overweight? thanks. Ben-Natan (talk) 02:56, 2 December 2014 (UTC)[reply]

Note, I ask the question after encountering some articles that have seem to contradict one eacherother. Ben-Natan (talk) 03:02, 2 December 2014 (UTC)[reply]

Well, what you're asking for is more in the realm of speculation on our part than sources (which you already have), which puts the request a bit outside the realm of what we are meant to be supplying here; but even putting the Ref Desks' specific guidelines out of the picture for the moment, this strikes me as the type of question that just about any neurophysiologist would decline to speculate on under most contexts, unless they had foreknowledge of, or access to, clinical findings exploring that very question. Neuromodulation of any sort is a fantastically complex process and just because one modulator has been associated with a given metabolic, behavioural, or cognitive/perceptual process does not necessarily mean one could predict an observable effect to the pathway in question as a result of a specific threshold of availability, especially not a prediction that runs cleanly and consistently in one-direction. Would you mind providing the conflicting sources in question? I for one feel more on solid ground assessing sources on the matter, and possibly supplying new clarifying sources, than I do speculating on a matter that would involve a massive chain of assumptions, any of which could be erroneous. Snow talk 04:19, 2 December 2014 (UTC)[reply]

For example: 1, 2, 3, 4. Ben-Natan (talk) 15:01, 2 December 2014 (UTC)[reply]

What is the reason that the covalent bonds are least specific?

I read the following sentence and I would like to get some help to understand it: "Drugs fit receptors using the lock and key model. Covalent bonds are the strongest and the least specific.". What is the reason that the covalent bonds are least specific? 149.78.231.106 (talk) 06:14, 2 December 2014 (UTC)[reply]

This wouldn't be a general statement, but just within the world of pharmaceuticals. Most drugs don't form covalent bonds with their targets, instead relying on things like van der Waals interactions. In order for a drug to form a covalent bond with the target, it needs to be more chemically reactive than most drugs. I think that is what is meant here, as they are more chemically reactive, they will be more likely to bind to non-target proteins. Fgf10 (talk) 07:51, 2 December 2014 (UTC)[reply]

It looks like this is a quiz generality. [31] The thing about generalities is that biology doesn't know theory, so they will always be wrong sometimes. Something like puromycin or carbon monoxide can be pretty specific to a particular process; you can argue that these reactions only proceed specifically because of the compounds' initial noncovalent interactions but that's a sort of No true Scotsman argument because any compound that interacts covalently with another will always have a certain degree of "noncovalent" interaction with the other reactants as part of the model for whatever reaction takes place. I suppose Fgf10's explanation is likely the reason, but I don't like the generalization. Wnt (talk) 09:34, 2 December 2014 (UTC)[reply]

Why is keratin not as conductive as the skin on your finger?

My iPhone does not react at all when I use the tip of my nail. But when I use the fleshy part of my finger, the iPhone reacts. 166.137.12.31 (talk) 19:16, 2 December 2014 (UTC)[reply]