Wikipedia:Reference desk/Archives/Science/2013 January 16

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January 16

File:Unknown hairy creature on stump.jpg

Can anyone find the name of this cute beast in latin and edit for rename on commons for me? Thanks in advance.--Canoe1967 (talk) 03:02, 16 January 2013 (UTC)

It's a gibbon or siamang, but there are some 16 species and I don't know which this is. It may be a juvenile given the coloring. Do we usually use images with copyright stamps on them? μηδείς (talk) 03:08, 16 January 2013 (UTC)

Kind of looks like a Yeti, presumably due to lack of clues as to the scale. StuRat (talk) 03:28, 16 January 2013 (UTC)

Gibbons are the smallest of apes. μηδείς (talk) 03:33, 16 January 2013 (UTC)

Images on commons are either copyright or public domain. Copyright ones need a free licence for use though. They can insist on attribution (credit) for every use of the image including derivatives. They can insist on name, company, and website displayed by every image if they wish. If someone wants to use it without credit near the image they may have to pay big bucks though.--Canoe1967 (talk) 03:39, 16 January 2013 (UTC)

I guess my point is that I don't ever remember having seen any image at wikipedia with a copyright watermark. I am wondering if such images are deprecated. μηδείς (talk) 03:50, 16 January 2013 (UTC)

The graphics volunteers remove them if they are really ugly and need to be used in articles. See: http://commons.wikimedia.org/wiki/Category:Images_with_watermarks Close to 3,000 now that have been put in the cats and probably far more that haven't.--Canoe1967 (talk) 04:08, 16 January 2013 (UTC)

Thanks, guess you're one o' them guys? μηδείς (talk) 05:00, 16 January 2013 (UTC)

According to the photographer, the photo was taken in São Paulo Zoo. So I guess the monkey is native to Brazil. Does it look like a female black howler? --PlanetEditor (talk) 04:51, 16 January 2013 (UTC)

No, it's definitely a gibbon, a south-east Asian/Indonesian ape of some sort, not a monkey. μηδείς (talk) 04:55, 16 January 2013 (UTC)

I agree it is a 'lesser ape'. I moved it to a more specific unknown category that I think is correct. It is probably harmless until someone wants a quality image of one with proper name. I see there are many unknown in the primate categories.--Canoe1967 (talk) 05:21, 16 January 2013 (UTC)

How about a White-handed Gibbon, (hylobates lar), which the São Paulo Zoo shows pictures of <re-dacted, site has viruses>. Richard Avery (talk) 08:27, 16 January 2013 (UTC)

Fantastic observation. There external features include black face, a white ring surrounding the face, white hair in hands. So it is likely a white handed gibbon. --PlanetEditor (talk) 08:38, 16 January 2013 (UTC)

Seems some admin over there got trigger happy. It is now called File:Something in latin sitting on a stump over water.jpg. I had prepped the re-name template waiting for a latin name and someone went and activated it. I hope they won't be mad when I ask for another re-name. Are we safe to call it: File:Hylobates lar sitting on a stump over water.jpg then? They like latin names for images over there, I think.--Canoe1967 (talk) 18:20, 16 January 2013 (UTC)

I can't open the link Avery has given; it gets a webkit failure in Safari and crashes Internet Explorer. It does seem likely by process of eliminating the other species by their images that this is Hylobates lar. 19:00, 16 January 2013 (UTC)

I'd go for it Canoe. They like latin names because they work in lots of languages and it avoids local names. Richard Avery (talk) 19:50, 16 January 2013 (UTC)

• 'WARNING!' The above link to the zoo lit up my anit-virus as trojan in it. I am going to redact it above.--Canoe1967 (talk) 20:00, 16 January 2013 (UTC)

Resolved

Thanks all for your help. I think I will ask a primate project if they want the watermark removed for articles.--Canoe1967 (talk) 21:06, 16 January 2013 (UTC)

Mars may get humid and muggy?

I never knew Mars may hit 100 F /38 C. However this source said Mars near equator at summer can hit 90 F. I thought Mars for most of the globe is colder than the coldest place on the Earth. Does mid-latitude ever get above 0 C/32 F or mid-latitude is colder than Antarctica and Greenland even on the summer days. Is the polar regions on Mars always cold. Is 70 F of Mars rare or it gets 70 F quite routinely. Is equator or tropical regions of Mars usually bone-chilly or it often gets 70s and 80sF?--69.228.25.10 (talk) 04:09, 16 January 2013 (UTC)

The very sparse Martian atmosphere has a very low heat capacity so its reaching higher temperatures due to insolation is not that surprising. μηδείς (talk) 04:59, 16 January 2013 (UTC)

Warm it may sometimes get, but "humid and muggy" requires atmospheric moisture, not common on Mars. HiLo48 (talk) 05:14, 16 January 2013 (UTC)

Yes, muggy implies a high humidity relative to human comfort, which you are simply not going to get in a CO2 atmosphere with 1% of the Earth's atmosphere's density. μηδείς (talk) 05:30, 16 January 2013 (UTC)

You have two main factors changing temperature on Mars relative to Earth:

1) The increased distance from the Sun makes it cooler, on average.

2) The thinner atmosphere and lack of oceans doesn't transport the heat as well, making it hotter where the sunlight hits, and cooler elsewhere.

Those two factors work in opposite directions at the equator, resulting in daytime temperatures similar to Earth. However, at the poles, both those factors move Martian poles towards being cooler than Earth, resulting in permafrost in areas permanently in shadow. Other minor factors affecting the temperature on Mars relative to Earth are it's reflectivity (albedo), lack of significant greenhouse effect (also due to the thin atmosphere), and tilt.

Also note that the temperature extremes result in migration of moisture towards the poles, in that any moisture at the equator evaporates on the hot days, then blows around until it gets someplace cold enough to precipitate/redeposit as ice. This happens on Earth, too, but here we have countering effects, like glaciers flowing from Antarctica into the ocean, melting, and returning the water to the equator. StuRat (talk) 05:27, 16 January 2013 (UTC)

The greenhouse effect is not at all minor. As our article says, Earth would have an average temperature of -18 degrees if it had no atmosphere, whereas its current temperature is 14 degrees. That's a difference of 33 degrees. --140.180.240.178 (talk) 06:34, 16 January 2013 (UTC)

Which degrees are those? Real Celsius ones, or those tiny American ones? HiLo48 (talk) 08:26, 16 January 2013 (UTC)

Why the Wedgwood scale of course. Who needs those newfangled new-age hippie temperature units anyway? --Guy Macon (talk) 09:01, 16 January 2013 (UTC)

One good thing about Fahrenheit is that you almost never hear it expressed as something-POINT-something (other than maybe 98.6) as it's finely-graded enough to give sufficient information as-is. ←Baseball Bugs ^{What's up, Doc?} carrots→ 14:01, 16 January 2013 (UTC)

That's a great argument. When are you getting the speedometer in your car recalibrated into inches per decade? SteveBaker (talk) 16:45, 16 January 2013 (UTC)

Not a good counter-example, since speedometers don't need to include decimal values in either MPH or KPH. Now, if in either system the top speed of a car was about 2, then we would need decimal values. StuRat (talk) 17:44, 16 January 2013 (UTC)

The better example of the latter is the Tachometer, which is typically divided into gradients. ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:36, 17 January 2013 (UTC)

Rather than just reading the entire source, I just look at Mars as it has seasons because it is tilt at 25.5 degree axis, so its pole will be colder and equator will be hotter because at planetary equator the sun is more direct than at poles. At equator I estimate 70-90 is rare, at 35 degree latitude, same latitude as Los Angeles on Mars I will say above freezing is rare, the further you move poleward on latitude on Mars, it will get colder. Mars doesn't have oceans or greenhouse gas so I know the temperature fluctuates greater than earth will.--69.228.25.10 (talk) 22:36, 16 January 2013 (UTC)

Hamiltonian

Is it an over-simplification to say that the Hamiltonian describes the wave-function; or is that just part of it? Lighthead ^þ 06:03, 16 January 2013 (UTC)

The Schrödinger equation describes the wave function. The Hamiltonian is the most important thing in the equation, but it is not the whole equation. Looie496 (talk) 06:17, 16 January 2013 (UTC)

Thanks a lot. That article is a lot easier to understand, at least from that vantage point. Thanks. Lighthead ^þ 06:28, 16 January 2013 (UTC)

(ec) It's not an over-simplification; it's simply wrong. The Hamiltonian represents the energy of a state, and is not specific to quantum mechanics. In fact, it originated in classical Hamiltonian mechanics, and that's the context under which most physics students know about it. I think it's rather confusing that our article specifically talks about the Hamiltonian in quantum mechanics without ever mentioning that it's the same, conceptually, as the classical Hamiltonian. --140.180.240.178 (talk) 06:30, 16 January 2013 (UTC)

Hmm... that's interesting. Hey! You should have an account on Wikipedia... unless you already do. Thanks. Lighthead ^þ 06:34, 16 January 2013 (UTC)

The Schrödinger equation article does specify, however, that the Hamiltonian is the total energy of the wave function. It doesn't describe it as exclusive to the wave function. Lighthead ^þ 06:42, 16 January 2013 (UTC)

Hamiltonian: This article needs improvement; and YOU can improve it! Lighthead ^þ 07:14, 16 January 2013 (UTC)

What needs improvement, specifically? Have you read our article on the interpretation of the Hamiltonian formulation? The application of these techniques to wave mechanics, or to atomic physics, builds on that prerequisite knowledge. Nimur (talk) 15:48, 16 January 2013 (UTC)

Harmful effect of excessive masturbation - Cortisol production

I came across an interesting piece here. According to the article, excessive masturbation results in increased production of cortisol. (Other sources support this fact) This cortisol in turn increases blood pressure, blood sugar, and results in insulin resistance. The website I cited is an alternative medical source, but their argument seems to be logical. On the other hand, mainstream medicine has always claimed masturbation does not have any negative effect. How does mainstream medicine refute their argument? --PlanetEditor (talk) 08:17, 16 January 2013 (UTC)

I suspect mainstream medicine would ignore their argument. There is no evidence it is based on any properly conducted and peer reviewed research, as medical science must be. Instead, it appears to be a commercial story used to promote the use of a particular herbal product. HiLo48 (talk) 08:24, 16 January 2013 (UTC)

... no doubt some marketing bright spark trying to capitalize on the deep-seated insecurity some people still have about masturbation, considering how strongly it was stigmatized in some Western countries until quite recently. If the argument applies to masturbation, it applies equally well to many other normal, healthy activities such as sex, sport, excitement etc. — Quondum 11:04, 16 January 2013 (UTC)

What a brilliant website. Although failing to define what "excess" means, their research clearly concludes that orgasm results in fatigue. Who'd a-thunk? Sounds kind of like General Ripper's discussion of "loss of essence". ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:43, 16 January 2013 (UTC)

Apparently "Most men limit the activity to three times a week", so maybe more than that is "excessive", making you one of the "others [who] tend to go overboard". AndrewWTaylor (talk) 14:01, 16 January 2013 (UTC)

Notice the weasel-wording there, based on some unsupported "most men" claim. Reminds me of this, from Annie Hall... Doctors: "How often do you have sex?" Annie Hall (Diane Keaton): "All the time. Three times a week." Woody Allen's character: "Almost never. Three times a week." ←Baseball Bugs ^{What's up, Doc?} carrots→ 15:38, 16 January 2013 (UTC)

Yeah - this is junk science at it's worst. There is no consideration whatever of the magnitude of the effect - or of possible beneficial effects from other changes this behavior might bring about (Oxytocin, for example, is produced in orgasm, and it has lots of beneficial effects). Certainly, the herbal remedies suggested there are guaranteed not to have been adequately tested for safety and effectiveness. Junk, junk, junkity-junk. Ignore it. SteveBaker (talk) 14:05, 16 January 2013 (UTC)

They have another article claiming over-masturbation results in increased production of DHT which in turn causes hair loss. Some other source does support this claim.

I remember once I masturbated more than 15 times in a single day after which I had headache, muscle weakness, fatigue and other symptoms of postorgasmic illness syndrome. --PlanetEditor (talk) 19:52, 16 January 2013 (UTC)

Use less strong porn the next time you masturbate for the first time in your life. I started with old women and only masturbated 10 times in single day.

• Do we have an article someone can link to about this masturbation? I have never heard of it before. μηδείς (talk) 23:11, 16 January 2013 (UTC)

• • You could start your investigation by locating a copy of Portnoy's Complaint. ←Baseball Bugs ^{What's up, Doc?} carrots→ 08:14, 17 January 2013 (UTC)

I don't think we give medical advice. Don't risk it. --DHeyward (talk) 04:28, 17 January 2013 (UTC)

Please help (weight of air)

I am a student. How do we take out the weight of air an object, say of 100 cm^2, is carrying? 115.253.44.234 (talk) 10:24, 16 January 2013 (UTC)

The weight of the air in the column above an object is equal to the atmospheric pressure multiplied by the cross-sectional area of the column. If this were 100 cm², this would be roughly 1000 newtons. If you want to know the net effect on the weight of an object due to atmospheric pressure, you need to take into account the upwards pressure underneath the object, which closely balances that from above. The overall effect is a slight reduction in weight equal to the bouyancy of the object in air, which comes to roughly 12 N/m³, which is the specific weight (weight density) of air. In most instances, this is so small compared to the specific weight of normal objects (roughly 1/800 of that of water) that it can be neglected in everyday contexts. — Quondum 10:51, 16 January 2013 (UTC)

If a box were a rectangular solid with the area of the face as the OP stated, and it were evacuated, would the pressure tending to crush it be only a function of the 100 sq cm of the top, or would the area of the sides matter? It seems like a hollow evacuated metal can 1 meter tall would need thicker walls than one 1 cm tall, both with 100 sq cm tops, to withstand atmospheric pressure. Being crushed is one "net effect" of atmospheric pressure, as is bouyancy. Edison (talk) 21:57, 16 January 2013 (UTC)

Crushing is a very complicated process, which depends on many things such as the geometry, internal structure, construction techniques, and so on. To a spherical cow approximation, crushing from pressure can be modeled as acting independently on each surface of the box. --Carnildo (talk) 02:46, 18 January 2013 (UTC)

Weight or mass? 1 mole of gas takes up 22.4 litres at Standard temperature and pressure. You would need to know the atomic mass of air and then figure out how many moles are contained in 100 cm^2. I think you need to compensate for the diatomic elements as well at 2x mass per mole.--Canoe1967 (talk) 23:32, 16 January 2013 (UTC)

Nitrogen is the main gas in air. Its article states density at 1.251 grams per liter.--Canoe1967 (talk) 01:54, 17 January 2013 (UTC)

I changed title to make it useful. StuRat (talk) 02:01, 17 January 2013 (UTC)

Yes there is a diffusive force the gas would exert on all sides of an evacuated vessel. The diffusive force is a function of the relative density inside the vessel and outside. This in turn is related to gravity and temperature of the gas. The force becomes a function of the surface area of the vessel but the "weight" of air is really just a function of the mass of molecules in a gravitational field. You can actually take a vessel, evacuate it, weight it at empty and then begin pressurizing it to 1 atmosphre pressure, 2 atmospheres, 3 atmospheres, etc while weighing it and you will see the "weight" of the air. As an aside, diffusive forces are also prominent in cell biology and creates osmotic pressure. It is also important in semiconductors and is a primary physical property on P/N junctions. --DHeyward (talk) 04:43, 17 January 2013 (UTC)

Vitamin K2 in ((Vitamins)) nav-box

Hi all,
At present, the vitamin K2 link in the nav-box points to Menatetrenone, which would appear to me to be a proprietary synthetic version of the naturally-occurring forms of K₂. I'm usually WP:BOLD, but in this case don't want to be WP:ALLTHEWRONGKINDOFBOLD.
Your thoughts and help as always sincerely appreciated. --Shirt58 (talk) 10:58, 16 January 2013 (UTC)

I'm not an expert, but the article does not seem to substantiate your conclusion about what the name Menatetrenone means (although the juxtaposition of the first two sentences in the lead of Menatetrenone is bad and they should be separated). The link pointing to a specific K₂-vitamin rather than to the general article does seem wrong (and misleading). It should evidently be changed to Vitamin K2, with the associated visible name changed from Menatetrenone to Menaquinones. — Quondum 11:46, 16 January 2013 (UTC)

Agreed, the link is wrong. Your reasoning is correct. Fgf10 (talk) 13:03, 16 January 2013 (UTC)

Okay, I did the deed. — Quondum 16:16, 16 January 2013 (UTC)

Thank you!--Shirt58 (talk) 10:23, 17 January 2013 (UTC)

Animal behaviour

Are humans the only animal who seek long term relationships for love and not just for reproducing? — Preceding unsigned comment added by 176.250.205.226 (talk) 11:24, 16 January 2013 (UTC)

'Love' is a product of human culture and society. I'm not sure we'd be able to recognise it in other animals. But bonobos and dolphins are well known to have non-reproductive sexual contact. AlexTiefling (talk) 11:30, 16 January 2013 (UTC)

Love is a product of biology caused by hormones and maybe influence a little by culture and society. I'm still incredulous that kissing was invented by the Romans. Doesn't it just happen when your faces get very close? Sagittarian Milky Way (talk) 22:28, 16 January 2013 (UTC)

There's also the common phrase about Swans mating for life and dying of depression if their partners are killed. The Swan article on Wikipedia confirms some truth to the mating part of it. Thanks ツ Jenova20 ^(email) 11:33, 16 January 2013 (UTC)

You could rephrase it a little to make it a question that can be answered with less speculation: Are there any examples of animals (except humans) where a male and a female form a pair and continue as a pair even when the female isn't fertile anymore? Sjö (talk) 12:50, 16 January 2013 (UTC)

There is considerable evidence that human females may be unique (or nearly so) in losing fertility before death. This paper suggests the possibility of non-human primates undergoing menopause (the end of female fertility) - but perhaps only in captive animals with enhanced lifespans compared to the same species in the wild. I was unable to find any studies that show menopause in other mammals or any other kinds of animal for that matter. Male fertility is even less likely to spontaneously end - even in humans, most men are fertile for their entire lives. So this question could only reasonably pertain to animals who lose fertility due to injury or disease. Under such circumstances, it would be hard to know whether that individuals' mate actually understands that fertility has been lost. Without modern medical advances, even a human would probably not know for sure except in very obvious cases.

So looking for species of animal that stay paired even after fertility has ended due to age or injury doesn't offer an answer here.

Perhaps a better answer is Homosexual behavior in animals - if such behavior produces pair-bonding between same-sex animals where reproduction is clearly impossible from the outset - then perhaps we can use this to form a reasonable answer.

So to pick just one example from Homosexual behavior in animals: "An estimated one-quarter of all black swans pairings are of homosexual males"...and from Black swan: "...the Black Swan is largely monogamous, pairing for life...". So if "pairing" is "love" then there are black swans who "love" despite no possibility of reproduction - then answer to our OP's question is "YesNo". But it's hard to attribute emotion to animals - especially non-primates - so whether pairing is "love" will probably never be known...it may not even be a meaningful question. Even humans are sometimes uncertain about whether what they feel is "love" or "lust".

On balance, I'd have to say that the answer is "YesNo" - but it's not a simple question. SteveBaker (talk) 13:31, 16 January 2013 (UTC)

Elephants, some whales and a few other animals seem to have a menopause, see menopause#In other animals. Dmcq (talk) 14:14, 16 January 2013 (UTC)

Yeah, there are a few - but many of them are in dispute (eg because the effect has only been seen in animals in captivity who live longer than they would in the wild) - and in any case, I didn't see that in species that exhibit long-term pair-bonding. SteveBaker (talk) 14:42, 16 January 2013 (UTC)

It's not just animals in captivity that have their lifespan "artificially" extended by having no predators, a steady supply of food, and by medical attention. All of those apply to humans as well. Our paleolithic ancestors living "in the wild" usually didn't live long enough to experience menopause either. --Guy Macon (talk) 18:14, 16 January 2013 (UTC)

Animals don't necessarily live longer in captivity, it fact it has been hard to ensure some live a normal lifespan. And it's quite likely our paleolithic ancestors lived much longer than people in poor places nowadays once they got past childhood - they often were nowhere near so poor. The article Life expectancy indicates they on average they lived long enough to have a menopause if they got past childhood. Dmcq (talk) 22:43, 16 January 2013 (UTC)

Exactly. It's a common idea that people died very young back then because the average life expectancy in the paleolithic was just 33 years. But averages are deceptive. There were a hell of a lot of deaths in childhood - which pulls the average life expectancy way down. According to our life expectancy article, anyone who managed to survive past the age of 15 had a life expectancy of 54 years - which is plenty enough to pass menopause (which in modern women typically happens between 42 and 58 years). By far the majority of adult females would have lived well past menopause even in the paleolithic. SteveBaker (talk) 16:28, 17 January 2013 (UTC)

The revised question is well-answered. It can however not be considered to be "rephrase[d] it a little": it is a very different question, with a very different answer. The answer to to the first, I think, is an unequivocal "no" (many species form long term pairing), though I realize some might object that we can't prove that any other animals feel "love" or that this is the basis for the pairing, to which I'd say a strong case should be possible that several do. — Quondum 14:36, 16 January 2013 (UTC)

From the lede of our article on Love: " "Love" may refer specifically to the passionate desire and intimacy of romantic love, to the sexual love of eros, to the emotional closeness of familial love, to the platonic love that defines friendship,[4] or to the profound oneness or devotion of religious love,[5] or to a concept of love that encompasses all of those feelings. This diversity of uses and meanings, combined with the complexity of the feelings involved, makes love unusually difficult to consistently define, compared to other emotional states."...it's clear that we cannot say whether any or all of those things are present in any non-human animals. Heck, we can't reliably show whether a human is honestly or consistently exhibiting this emotion according to that definition.

Our article Biological basis of love describes a whole slew of chemical signatures of human "love" - we could ask whether those chemical signatures are present in pair-bonded animals. Oxytocin is a major signature indicating long-term love - but it has other roles in the body. Our article says: "Virtually all vertebrates have an oxytocin-like nonapeptide hormone that supports reproductive functions". You can follow the same papertrail for vasopressin (another "long-term-love" hormone in humans) and arrive at the same conclusion. So that suggests that other vertebrates might also feel the emotion...but perhaps not invertebrates.

Biological basis of love also says that the Limbic system (a structure in the brain) is heavily involved in the emotion - and that system was present in the common ancestor of mammals and reptiles - so perhaps vertebrates who lack a limbic system might not qualify as passionate lovers.

SteveBaker (talk) 14:57, 16 January 2013 (UTC)

I posted the other day on WikiProject Biology asking if anyone could improve our article pair bond. No answers there yet, would be good to get some attention tithe article Itsmejudith (talk) 22:15, 16 January 2013 (UTC)

• Without reading the whole discussion, I think bald eagles mate for life if that is any help.--Canoe1967 (talk) 23:36, 16 January 2013 (UTC)

Hmmm. Mushroom spores produce primary mycelium; these primary mycelia fuse and form secondary mycelium in which the two individuals join as one to go about their lives (See Plasmogamy). One might argue this is a more profound relationship toward certain religious notions of marriage merely aspire. Of course, you can say "is that love?" because mushrooms don't think the way humans do; and you ask that of any animal. For now, lacking a proper theory of consciousness, it is a matter of semantics/definitions, I suppose. Wnt (talk) 00:10, 17 January 2013 (UTC)

Here is a link about animals that mate for life. On the other hand, this paper claims humans are genetically polygamous. --PlanetEditor (talk) 02:02, 17 January 2013 (UTC)

More specifically, the claim is that humans are more polygynous than polyandrous in terms of reproductive success, or at least that they have been (though I suspect that nothing has changed in this regard). — Quondum 13:34, 17 January 2013 (UTC)

There is no argument whatever that many other species pair-bond for life. Finding more examples of that doesn't advance our answer here...it's a given...similarly, it's pointless to ask whether humans are genetically polygamous or not...it's known that a significant majority of us do in fact pair-bond for life and that most will experience the emotion that we label as "love". It's also known that the majority of us continue to pair-bond beyond female menopause. There is really no debate about those things.

The two difficult parts of the problem are:

1. Can pair-bonding in non-human animals be equated with the human emotion called "love"?
2. Do any non-human, pair-bonding species lose fertility as they age?

The first is ridiculously difficult to answer - the definition of "love" is very broad and the question of "do members of species X love each other" is unfalsifiable - in fact "does anyone other than me exhibit this emotion" is unfalsifiable too! We have to guess that the chemical signatures of human pair-bonding (which generally includes feelings of love) are a close match for those found in other vertebrates - and the brain structures involved are present in at least mammals and reptiles. If that's enough to satisfy the conditions of the OP's question - then we have some sort of an answer - but "love" is a very vague term and a rock-solid answer is impossible, even in principle.

The second seems to be almost always "no" - but there are a few exceptions (elephants, whales) - but even those have patchy evidence, may only apply to animals in captivity who outlive their natural lifespans. We currently have no examples of animals that are thought to lose fertility as they age that are also known for pair-bonding - which means that this question of whether "love" ends at menopause in other pair-bonding species is meaningless because they never have menopause.

I was able to show that there are several species where same-sex pair-bonding is common...and in that case, "love" (if we accept #1) is occurring where there is no chance of producing offspring...but that's not the same thing as "losing fertility with age"...so I'm not sure it counts.

On balance, we should say that humans are indeed the only species who do this...but not because we're the only ones who'd care about their mates after fertility has ended - it's because fertility simply doesn't end in most other species, so the question of what would happen if it did is moot.

SteveBaker (talk) 16:19, 17 January 2013 (UTC)

Sudden blindness

can sudden blindness occur even when you get frequent follow up eye exam or would the exam reveal progression of nerve damage to the eye retina — Preceding unsigned comment added by 69.141.51.81 (talk) 14:11, 16 January 2013 (UTC)

alternative (natural means)for treating eye pressure without eye drop medication — Preceding unsigned comment added by 69.141.51.81 (talk) 14:13, 16 January 2013 (UTC)

WARNING: We're not allowed to give medical advice here. That said, Blindness#Causes suggests that some causes of blindness (eg methanol poisoning) might be too sudden to show up with frequent eye exams...where others (eg cataracts) should be detectable long before they cause significant vision loss, so frequent eye exams might discover the cause before significant blindness results from it. So the answer to your first question depends on the cause of blindness.

For your second question: Our article Ocular hypertension suggests that acetazolamide is a common treatment for excessive "eye pressure" that does not require eye drops - but, again, it all depends on the cause of the eye pressure. Some causes might require drops.

These are complicated and difficult matters - and nobody can know what's right for a particular individual without a careful medical examination. SteveBaker (talk) 14:39, 16 January 2013 (UTC)

Regular eye examinations are only going to show the progress of degenerative conditions. Oddly the article on blindness and specifically the section on causes does not mention retinal thrombosis which can, without warning, cause complete loss of sight in the affected eye within hours. Richard Avery (talk) 16:19, 16 January 2013 (UTC)

(You should probably dive in and fix the article! Finding and fixing such errors is a part of the function of the reference desk.) SteveBaker (talk) 16:41, 16 January 2013 (UTC)

• Is it coincidence that that section is just below a section on harmful effects of excessive masturbation?--Canoe1967 (talk) 23:42, 16 January 2013 (UTC)

The second question may be addressed by Glaucoma#Research ("Natural compounds"). Marijuana has had longstanding use for the condition, occasionally even being preferred by some patients who say that it is more effective than other medications. Of course, on an individual case basis a person would need a clear medical diagnosis of the exact type, and discuss drug options (though I suspect the physician's recommendation natural vs. non would often be less a matter of individual diagnosis than which drugs he is permitted to push in his state...) Seriously though - if your interest is more than academic, you need more help than random Wikipedians responding to a vaguely worded sentence. Wnt (talk) 23:51, 16 January 2013 (UTC)

ImageJ macro for batch merge of images

I have image files named in the format:

Exp.SS.4.4.170 - DF1 - MSTN HDR donor candidate 1 - 2 ul Lipofectamine 2000 - 15x - Field 1 - Brightfield - 2012-12-16.tif

Exp.SS.4.4.170 - DF1 - MSTN HDR donor candidate 1 - 2 ul Lipofectamine 2000 - 15x - Field 1 - UV red - 2012-12-16.tif

Exp.SS.4.4.170 - DF1 - MSTN HDR donor candidate 1 - 2 ul Lipofectamine 2000 - 15x - Field 2 - Brightfield - 2012-12-16.tif

Exp.SS.4.4.170 - DF1 - MSTN HDR donor candidate 1 - 2 ul Lipofectamine 2000 - 15x - Field 2 - UV red - 2012-12-16.tif

etc

I would like to merge each "Brightfield" image with its associated "UV red" image using ImageJ. Can anyone help me put together a macro to do this?

I tried using the built-in macro recorder but it doesn't pay attention to how much I increased the contrast of the red images and it also uses specfic file names which is useless when each file is named differently (obviously; you can't have two files with the exact same path!) 129.215.47.59 (talk) 14:23, 11 January 2013 (UTC)

Maybe better to ask this at the Computing Desk. - Lindert (talk) 14:39, 11 January 2013 (UTC)

Computing people probably don't deal with ImageJ. ImageJ is an NIH application. 72.229.155.79 (talk) 19:21, 11 January 2013 (UTC)

One can always try, and most people here on the science desk don't work for the NIH either (if there are any at all). Also ImageJ is open-source and has many useful functions, so maybe some 'computing people' have used it. Anyway, if you still think this is the best place, just forget I said anything. I'm afraid I can't be of much help, but good luck finding an answer. - Lindert (talk) 20:38, 11 January 2013 (UTC)

It would help if you could upload the actual images. What exactly would this merge do ? Are you talking about combining the red from one image with the blue and green from another ? Are the images of the same size and already properly aligned ? StuRat (talk) 23:16, 11 January 2013 (UTC)

Hi. The images look like this.

Bright field

UV red

Merged

Precedure to merge one pair of images

Open brightfield image. Image>Type>8-bit

Open UV/red image. Image>Adjust>Brightness/Contrast and increase contrast five clicks

Image>Type>8-bit

Merge channels - set C1 (red) as UV/red image and set C4 (gray) as brightfield image.

Save new image with name: Exp.SS.4.4.170 - DF1 - MSTN HDR donor candidate 1 - 2 ul Lipofectamine 2000 - 15x - Field 1 - Merged - 2012-12-16.tif

Macro as recorded by ImageJ during above procedure

open("B:\\Sean Smith\\M\\DF1\\Ex.SS.4.4.170 - 2012-12-13\\Exp.SS.4.4.170 - DF1 - MSTN HDR donor candidate 1 - 4 ul Lipofectamine 2000 - 15x - Field 1 - Brightfield - 2012-12-13.tif");

run("8-bit");

open("B:\\Sean Smith\\M\\DF1\\Ex.SS.4.4.170 - 2012-12-13\\Exp.SS.4.4.170 - DF1 - MSTN HDR donor candidate 1 - 4 ul Lipofectamine 2000 - 15x - Field 1 - UV red - 2012-12-13.tif");

//run("Brightness/Contrast...");

//run("Brightness/Contrast...");

run("8-bit");

run("Merge Channels...", "c1=[Exp.SS.4.4.170 - DF1 - MSTN HDR donor candidate 1 - 4 ul Lipofectamine 2000 - 15x - Field 1 - UV red - 2012-12-13.tif] c4=[Exp.SS.4.4.170 - DF1 - MSTN HDR donor candidate 1 - 4 ul Lipofectamine 2000 - 15x - Field 1 - Brightfield - 2012-12-13.tif]");

saveAs("Tiff", ""B:\\Sean Smith\\M\\DF1\\Ex.SS.4.4.170 - 2012-12-13\\Exp.SS.4.4.170 - DF1 - MSTN HDR donor candidate 1 - 4 ul Lipofectamine 2000 - 15x - Field 1 - Merged - 2012-12-13.tif");

129.215.47.59 (talk) 14:42, 14 January 2013 (UTC) — Preceding unsigned comment added by 78.144.207.252 (talk)

I can't help, but you could also try asking at a forum specifically for imageJ. This one [1] seems to have some good answers. SemanticMantis (talk) 15:39, 16 January 2013 (UTC)

The only general advice I can give for this sort of thing is to use entirely keyboard shortcuts or command line commands when recording a macro. Often the mouse-y bits get lost, but the other methods will successfully record. SemanticMantis (talk) 15:40, 16 January 2013 (UTC)

effect of touch

how does a touch such as a pat on the back make you feel good? what happens in the brain to register this as a pleasurable sensation? thank you.24.27.44.43 (talk) 23:12, 16 January 2013 (UTC)

Being touched is not universally something that "makes you feel good". Humans and animals both will respond positively or negatively to being touched, depending on whether they are "used to it" and whether they trust the one doing the touching. ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:29, 17 January 2013 (UTC)

i understand that and am interested whether positive or negative. i would like to know where in the brain, what neurotransmitters, etc. i have not been able to find much information on the science of touch.24.27.44.43 (talk) 00:52, 17 January 2013 (UTC)

Two sources. --PlanetEditor (talk) 02:12, 17 January 2013 (UTC)

The article Physical intimacy says "A hug or touch can result in the release of oxytocin, dopamine, and serotonin, and in a reduction in stress hormones." These are all linked to positive perceptions. — Quondum 07:45, 17 January 2013 (UTC)

Certainly oxytocin is produced during prolonged hugging - and that definitely makes you feel good. I don't know that a pat on the back would also have that effect though. It's more likely that there is a psychological feeling that the other person appreciates you or something. I wonder if there are cultures in the world where back-patting isn't a gesture of support or appreciation? SteveBaker (talk) 15:56, 17 January 2013 (UTC)

How hot?

How hot would the air get if you put a car in the center of a house (some disassembly may be required), found an alternative source of air, and then ran the engine till everything reached thermal equilibrium?

Of course it would depend on a number of factors, like where on the scale from F1 car to Corolla, idling or full throttle, your insulation, outside temperature, whether you're measuring outside the vehicle or inside with doors and windows closed, and whether it's is in neutral or running on rollers. Would it even run that long before something breaks? Maybe coolants and lubricants not reccomended by the manual could let it last longer, possibly at the expense of extensive damage? Sagittarian Milky Way (talk) 23:28, 16 January 2013 (UTC)

I have reformatted this and closed it. Anyone who has sources can give them outside the hat. μηδείς (talk) 23:33, 16 January 2013 (UTC)

I've reopened this question because although the exact temperature obtained depends only on fuel consumption, the amount of space heated and heat loss to the outdoors, precision isn't needed to answer this question, only accuracy. --Modocc (talk) 01:10, 17 January 2013 (UTC)

This can't be estimated with R-values of walls, horsepower, and the 25-30% efficiency of internal combustion engines? Sagittarian Milky Way (talk) 23:37, 16 January 2013 (UTC)

Hmmm. In brief an internal combustion engine is not a steam engine - there's no fundamental reason that I know of why it can't work without cooling. Yet I can't think of one that really does work without a radiator (engine cooling) functioning. So I'm not sure if the limit here is something that can be worked out from first principles or if it's a matter of engineering. Also there are some aspects of the question left unspecified, i.e. whether there is free input of cool outside air, what happens to the exhaust and so forth. The simplest version is that if you put a very good insulated enclosure around a car engine (but preserve normal engine cooling functions!) then you'll have the enclosure at the same temperature as the engine. You might want to take a step back and think if there's a simpler way to express what you're actually wondering about. Wnt (talk) 23:59, 16 January 2013 (UTC)

If you try to run an internal combustion engine without cooling, the oil breaks down, and combined with the expansion of metal parts this causes the cylinders to seize, which causes the engine to come apart. Looie496 (talk) 00:16, 17 January 2013 (UTC)

Practically speaking, it would be basically just an overly complicated gasoline furnace, unless you have some mechanical work for the engine to perform, because the moving parts are unnecessary (these parts will store a fairly small amount of kinetic energy as long as these are in motion). [Note that gasoline is not generally used for heating purposes though due to its high volatility]. In addition, carbon monoxide from the exhaust is a danger and must be vented to the outdoors. This is best done with a heat exchanger that brings in fresh air which gets heated (these heat exchangers can be over ninety percent efficient). If vented properly, the space would get just as hot as with a regular gasoline furnace consuming the same amount of fuel. For a fictional version of a machine that was morphed into a furnace, see Mike Mulligan and His Steam Shovel. -Modocc (talk) 01:00, 17 January 2013 (UTC)

If the question is serious, the OP should ask at the mathematics desk for an equation that would address all the relevant variables. As it stands the question is fatally ill-formed (what's the heat capacity of the house, for example) and the answers more like random wall spaghetti than links to references that will actually answer what's asked. μηδείς (talk) 01:16, 17 January 2013 (UTC)

Meh, I disagree that this belongs elsewhere. Its an applied science or engineering problem. Perhaps I'm being presumptive, but the question seems to be more along the lines of how practical it is to use a car engine for heating, as in can it heat a given space (maintaining an equilibrium). There does exist resources for various furnace capacities and recommendations for such purpose. -Modocc (talk) 01:32, 17 January 2013 (UTC)

We've still got not question and no referenced answers, but we do have a single-purpose account reopenning trolling by another single-purpose account. Discuss this at talk before reopenning. μηδείς (talk) 02:24, 17 January 2013 (UTC)

It seems like a fine thought experiment. —Steve Summit (talk) 03:28, 17 January 2013 (UTC)

Due to gasoline's high volatility, it is not generally used in space heaters (or furnaces for that matter) here in the USA (but gasoline can be used in outdoor camping gear and it seems I recently read about it being used for space heating elsewhere, furthermore it was at one time used in cars and aircraft, see the article on gasoline heaters). Kerosine heaters used to be somewhat common (its similar to gasoline, but is considerably less volatile). Because of this, gasoline should not be used in a home. In any case, that said, power for space heaters and furnaces are rated in BTUs per hour. For homes, recommended furnace BTUs start at 60,000 BTU/hr: [2]. Gasoline engines that are running at idle speed, consume roughly between .4 and 1.2 gallons per hour: [3]. At one gallon per hour, according to Onlineconversion.com, converting the energy content of a gallon of gasoline to kilocalories, this yields 31,470 kilocalories/hr or 124,883 BTU/hr which is more than enough heat. I'm sometimes prone to dumb errors though, so someone should double check my figures. -Modocc (talk) 06:27, 17 January 2013 (UTC)

Looking into the energy content of these fuels a bit more, I found a useful tabulation of gasoline gallon equivalents. The GGE of kerosine, which would be safer to use, is 0.9000, thus it has more energy per gallon than gasoline. -Modocc (talk) 08:35, 17 January 2013 (UTC)

There have been various proposals and even some working engines that are adiabatic -- engines made out of ceramic that require no cooling. So far nobody has solved the lubrication/wear problem to make one last as long as a conventional engine. Now of course any IC engine loses heat from the fact that exhaust is hotter than the intake, and with the adiabatic engine the incoming air is really quite cold compared to the engine, while the exhaust is still very hot. the thermodynamics of IC engines are such that whatever energy from the burning fuel that doesn't result in power output needs to be removed somehow or the temperature will increase without limit. --Guy Macon (talk) 06:53, 17 January 2013 (UTC)

There are indeed some modern home heating units that use a Stirling engine to produce electricity that is fed into the grid, and only use the "waste heat" for heating. That seems like a very good concept, at least in principle. --Stephan Schulz (talk) 13:21, 17 January 2013 (UTC)

Oh come on Ref.Deskers...we can do better than that! Obviously our OP isn't looking for a precise answer - this is a highly "back-of-envelope" calculation with lots of assumptions built into it to get a rough idea of what would happen.

It seems to me that once equilibrium has been attained, 100% of the energy in the gasoline either turns up as heat (one way or another) or as heat and unburned gasses in the exhaust. For now, let's assume that the pipe that takes the exhaust outside is long enough to act as an efficient heat exchanger - and we'll ignore unburned fuel in the exhaust and assume that that the car is just a complicated way of turning the energy in the gasoline into heat. We'll assume that nobody is revving the engine here. A google search reveals that a typical modern 4 cylinder engine burns about a quarter of a US gallon of gas per hour at idle (infinite miles-per-gallon!). The energy density of gasoline is 36.6 kWh/USgal - so the car is at best a 10kW heater...probably worse because we're ingoring fuel/heat coming out of the tailpipe - which is significant at idle.

A "typical" 2000 sq.ft US home (not in Alaska or Nevada) needs a 40kW heater to keep the place comfortable through the year - so right off the bat, we know that this car is a pretty poor heater. If that's your only source of heat then the house is going to be pretty cold in winter! The effect of adding a car into your heating system would have a similar effect to cranking up your thermostat until it increases your heater's energy consumption by about 10kW - which is about 25%. Well, the common advice on saving energy is that you add 1% and 3% to your heating bill for every degF you crank up the thermostat...so the car would likely increase the temperature within the house by between 8 and 25 degF.

How big are the "error bars" on this calculation? Huge, obviously. We don't know the kind of car, whether it's being revved, how big the house is, how well insulated it is, what the outside temperature is, what the exhaust losses are. But what we can ascertain from "typical" numbers is that your house would get quite a bit hotter - but the car alone couldn't replace your heating system.

SteveBaker (talk) 15:50, 17 January 2013 (UTC)

Very good, except for the last part. If you do indeed rev up the engine, you can easily get up to 10 times the fuel consumption (based on 10 l/100 km just to spite the imperialists ;-). So you can turn it into a 100 kW heater. Also, the result very much depends on the quality of the isolation. In Germany, we now have so-called passive houses which are so well isolated that they normally need no extra heating. For very cold situations, the have a 2 kW heater integrated into the controlled ventilation system. So there is another order of magnitude ;-).--Stephan Schulz (talk) 16:11, 17 January 2013 (UTC)

Yes - I agree. As I said, the error bars are huge. But for a "typical" idling US car, US house, US insulation, mid-US winter day - I'd stand by the 8 to 25 degF temperature rise. If you did the experiment with a Toyota Prius, you'd get almost no heating at all (the tiny gasoline engine shuts off automatically when the car is stationary, so it runs on batteries until the digital clock runs them down enough for the engine to kick in and recharge them - that probably takes a hundred years to happen!). If you did it with a hard-revved Ferrari 612 Scaglietti (which has probably the worst fuel economy of any production car) in a "passive house" during a heat-wave - then you're going to get really hot, really fast! We don't have enough information to answer the question in general - but I believe that in the spirit of how it was asked (a back-of-envelope thought experiment) - the answer is as I've suggested. SteveBaker (talk) 16:43, 17 January 2013 (UTC)

I will trade you a top-of-the-line home heating/cooling system for that Ferrari Scaglietti you have there. No need to thank me. :) --Guy Macon (talk) 16:49, 17 January 2013 (UTC)

Sadly, the '06 Scaglietti has a clutch sensor that malfunctions in excessive heat and Ferrari say that it "may render the vehicle inoperable and possibly result in a crash" - I'm sure you wouldn't want it crashing while it's parked in the middle of your basement with all of those heating ducts wrapped around it. :-) SteveBaker (talk) 17:51, 17 January 2013 (UTC)

I've mentioned this before, but I've devised a machine which can put a stop to our reliance on fuels altogether and with any luck, I've every intention on completing it soon too. The idle speed fuel consumption data I linked to is old, from the early 70s, but is still important, for it shows that sufficient fuel can be burned to produce enough heat for a small home within a moderate climate without over-revving many engines, especially the larger and older ones. Even newer engines could be put under a load such as an electric generator to crank out more heat at fewer RPMs. I just spoke with my friend whose grandfather sold Model-Ts and he tells me their engines (which could run on petrol, kerosene or ethanol) were more efficient than later engines because of a cleaner burn (I haven't found any data to support that though), but today's fuel injected cars are even more efficient and I do not think waste huge amounts of unburnt or incompletely burnt fuel to the exhaust. So other than matching the engine or engines (lets say two of them if needed) with the space and loads, there is no reason these cannot be used to provide heat (as with the OP's thought experiment) and electric power. I'll add that where I live, heat pumps are better, but it would be nice to have an electric generator installed too. -Modocc (talk) 18:32, 17 January 2013 (UTC)

"I've devised a machine which can put a stop to our reliance on fuels altogether" - So what does it run on? AlexTiefling (talk) 22:37, 17 January 2013 (UTC)

Modocc has previously claimed to have found a loophole in the 2nd law of thermodynamics - and hence is presumably building an over-unity perpetual motion machine of the second kind (a machine that can reverse the direction of entropy or some such). So...um...well. What does one say to that and remain within the bounds of WP:AGF? Er..."Good luck"? SteveBaker (talk) 23:52, 17 January 2013 (UTC)

That almost sums up my position, but "over-unity" is incorrect because that would be a violation of the perfection of the first law or the conservation of energy. Of course, the second law is very useful and seemingly ubiquitous, but, yes, I've figured out a way to completely defeat it. Modocc (talk) 00:28, 18 January 2013 (UTC)

Well, you better patent it before you talk about it too much here, then. Especially now that the US uses (the idiotic) first to file rule. --Trovatore (talk) 00:47, 18 January 2013 (UTC)

[4] As per the previous discussion Modocc needs to build a working model first since the idiotic US now uses the idiotic 'need a working model if it violates basic physics' rule. Well you can submit a working model later possibly but as with all applications you're SOL if your patent application is incomplete, the idiotic US has more idiotic rules limiting people from adding stuff they forgot or 'forgot'. Unfortunately their physical limitations make building a working model of this ground breaking work difficult. P.S. As per the article you linked to, ignoring the idiotic constitutional issues, the idiotic US does not actually currently use idiotic first to file rule but instead uses the idiotic first to invent rule so the OP still has time. Nil Einne (talk) 02:54, 18 January 2013 (UTC)

Given that the US patent office probably rejects any kind of perpetual motion patents, he's probably got all the time in the world. Vaguely related: I wonder where the patent office stores all those working models? Maybe in the Smithsonian? ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:06, 18 January 2013 (UTC)

The rule on perpetual motion machines is that there has to be a working model. That's not true of most other patents. Where would the patent office store all of these fully-working perpetual motion machines? Well, I guess they'll cross that bridge when they come to it. :-) SteveBaker (talk) 16:11, 18 January 2013 (UTC)

If the only models they require are for perpetual motion machines, then they probably store them in Shangri-La. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:18, 18 January 2013 (UTC)

They get sent to The Museum of Unworkable Devices. They have a secret cellar where they stow away all devices that actually work. It's all part of the same cover-up, you see.

Now, in a more serious tone. Modocc, nobody will believe you until you have a workable device. And then you will have to get it tested by independent teams. --Enric Naval (talk) 22:48, 19 January 2013 (UTC)

Perhaps, because believability would certainly be an issue if I were to choose to make it public before I complete it. I'm not infallible of course, but unlike the nonsense of cranks that you might be more familiar with, my invention is not difficult to comprehend or to implement. Yet because of strong prejudices and the possibility of missteps in any publication, I am working on simply building the device. -Modocc (talk) 02:08, 20 January 2013 (UTC)