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June 8

The pleasure of sneezing

Hardly a day ever goes by when I don't sneeze at least once. It never bothers me; in fact, I like it a lot. Just before the expulsion of breath I experience a feeling that is intensely pleasurable; it's up there with orgasm in terms of pleasure. I'm sure others have this feeling too.

What is the biological purpose of this intensely pleasurable feeling? -- Jack of Oz ^{[pleasantries]} 07:06, 8 June 2017 (UTC)[reply]

Not every biological phenomenon has a 'purpose' (which in itself is an ontologically loaded term); sometimes they are just side effects of some other process, or arise by chance. If they are neutral in terms of survival, they will neither be selected for nor selected against. {The poster formerly known as 87.81.230.195} 2.217.208.38 (talk) 07:19, 8 June 2017 (UTC)[reply]

(ec) Googling "sneeze pleasure" gives a few interesting results, showing that you're not the first to wonder about this, though they seem to be more about what makes sneezing pleasurable rather than "why". And WP:WHAAOE: Sexually induced sneezing. AndrewWTaylor (talk) 07:23, 8 June 2017 (UTC)[reply]

Great. What I need now is a sneezing induced erection. :) -- Jack of Oz ^{[pleasantries]} 08:03, 8 June 2017 (UTC)[reply]

So when someone says you "sneezed hard", it wasn't about the strength of the lung action? DMacks (talk) 08:09, 8 June 2017 (UTC)[reply]

Hmm. Maybe a drug-free cure for erectile dysfunction is in the offing: Sneeze yourself hard. Worth a try. Hand me that pepper shaker, please. -- Jack of Oz ^{[pleasantries]} 09:50, 8 June 2017 (UTC)[reply]

I guess snuff film needs to become a DAB page. DMacks (talk) 13:54, 8 June 2017 (UTC)[reply]

Unknown Antilope

May you please help me identifying this Antilope species?--Erasmus Wolfgang Blivet (talk) 10:18, 8 June 2017 (UTC)[reply]

Unfortunately the park's web site doesn't contain anything like a list of all the species they have. But it does mention that they have elands, and while I'm no expert, I'd say that creature looks a lot like the ones shown in the common eland article. --69.159.63.238 (talk) 10:41, 8 June 2017 (UTC)[reply]

I agree. Definitely a Taurotragus of some sort. Note the dewlap and the distinctive horn spiral. Quite common where I live. 196.213.35.146 (talk) 12:54, 8 June 2017 (UTC)[reply]

War stories

Why does my grandfather constantly talks about the war? He's 94 and for the past 20 or so years, ever since I remember actually, he's been telling WW2 stories to everyone willing to listen.

He always talks about 1941-1945, very rarely about the this life before or after the war.

Its like the granpa Trotter from Only fools and horses.

How come some people always talk about the war even though it's such a small fragment of as opposed to the rest or their lives? Is there a scientific explanation ? — Preceding unsigned comment added by 212.200.247.175 (talk) 16:26, 8 June 2017 (UTC)[reply]

For many of that generation, the war was by far the most extraordinary experience of their lives. Cut him some slack. And maybe record what he says, because you may find it useful once you've grown up. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:40, 8 June 2017 (UTC)[reply]

Agreed; and many of them feel that it's their duty to pass on their experiences to the younger generations. There's not many of them left now. Alansplodge (talk) 22:47, 8 June 2017 (UTC)[reply]

From the perspective of a daughter of a survivor of the worst of World War 2, your grandfather probably had untreated PTSD, for which we now prescribe talk therapies. He is undergoing his own self-treatment of his PTSD, even 70 years later, as it was not treated at the time. You could also think of it this way: there is a proverb "he who does not learn from history is condemned to repeat it". The best way to ensure the mistakes of history are not learned is to ensure that they are forgotten. So from that perspective, your grandfather is anxious that you and your generation don't suffer like he and his generation did. Be gentle, and as others have said, cut him some slack and make notes of what he says. Your future self will thank you for it. --TammyMoet (talk) 16:08, 10 June 2017 (UTC)[reply]

We're not really qualified to make diagnoses. An alternative explanation is that war is obviously interesting; otherwise why are there so many war movies? A religious person might say that God made Nazis for the sole purpose of allowing us to watch them die in entertaining ways. (Then again, maybe not...) It is entirely possible that if he had not been in a war, he would have gotten involved in a World of Warcraft game or a Civil War reenactment or something and bored you to death with stories about that instead. So be thankful (but not too thankful) for our Axis friends. But we don't know scientifically why any one person does what he does, and generally the actions of a crowd are even less logically explicable. Wnt (talk) 16:43, 10 June 2017 (UTC)[reply]

What solvent to rejuvenate a solvent resistant pen?

When I was a kid and a felt tip pen dried out, it could be revived by adding just a couple of drops of water from the back end of the pen. I have a marker pen which is solvent resistant and won't come off with ethanol but will come off with some solvents such as methanol. What can I add a couple of drops of to rejuvenate my pen? (I know I can't do this forever) — Preceding unsigned comment added by 129.215.47.59 (talk) 16:33, 8 June 2017 (UTC)[reply]

I've woken up dried-out VWR lab markers with a histo-grade mixture of xylenes. Wnt (talk) 18:14, 8 June 2017 (UTC)[reply]

carbon monoxide

Is CO heavier or lighter than air? — Preceding unsigned comment added by 2601:601:8600:F1:15D3:932D:A7F8:B18F (talk) 19:41, 8 June 2017 (UTC)[reply]

For most practical applications carbon monoxide is essentially the same as air. Dragons flight (talk) 20:02, 8 June 2017 (UTC)[reply]

You are likely referring to molar mass. Carbon Monoxide is 28.01. Air tends to be around 29. While lighter than average air, the difference is so slight that, as Dragons flight stated, carbon monoxide is essentially the same as air. 209.149.113.5 (talk) 20:24, 8 June 2017 (UTC)[reply]

Our Carbon monoxide#Molecular properties notes, "Carbon monoxide has a molar mass of 28.0, which, according to the ideal gas law, makes it slightly less dense than air, whose average molar mass is 28.8." DMacks (talk) 21:36, 8 June 2017 (UTC)[reply]

Where can I get reliable info about LDL and HDL in quail eggs?

I read the article quail eggs but no information about that. In one place on Google I found that it's without LDL at all, it has HDL ("good cholesterol") only. In another place I found that it has high levels of cholesterol which can damage. So I assume, based on the last site, that it has LDL as well, otherwise it's not dangerous to eat good cholesterol. Isn't it? 93.126.88.30 (talk) 20:23, 8 June 2017 (UTC)[reply]

This looks promising.--Jayron 32 20:27, 8 June 2017 (UTC)[reply]

The USDA doesn't differentiate between types of cholesterol. They list a 9g quail egg as having 76mg of cholesterol [1]. It is less than 1% cholesterol. However, this leads to why you ask. If it is because you believe that consuming cholesterol will raise cholesterol in your blood, please look into where that concept came from and the years of research that has shown the concept to be completely wrong. 209.149.113.5 (talk) 20:30, 8 June 2017 (UTC)[reply]

Low density lipoprotein and high density lipoprotein are not eaten. (Well, alright, alright, I suppose you do eat them in meat and the enclosed blood therein, but in any case, proteins that are eaten get cut up into pieces and don't usually make it into the body intact; they generally have to be rebuilt from scratch according to our blueprints) They are chylomicrons formed by the interaction of ingested fats with apolipoproteins, proteins produced mainly in the liver, to allow their distribution throughout the body. While in theory it would be possible for some food sources to encourage more LDL or HDL production by any number of regulatory means, the fats themselves, including cholesterol, can be found in either. I highly doubt that any one species of bird produces a haloed egg capable of producing only good cholesterol, but this is biology where anything is possible ... I'd have to do an experiment (or find one) to actually know. Wnt (talk) 23:30, 8 June 2017 (UTC)[reply]

Taxonomy confusion

Does a species scientific name encompasses all subspecies.

For example does the scientific name of the species called lion "panthera leo" means at the same time all subspecies it has?

To visualize another example:

Is panthera leo = panthera leo leo, panthera leo spelaea, panthera leo atrox, panthera leo asiatica...

If my question is answered with YES, Are there exceptions to this in taxonomy?

For example does the scientific name Canis lupus refers to all its subspecies including the dingo and the dog?

Gyrkin (talk) 20:29, 8 June 2017 (UTC)[reply]

See subspecies. A subspecies cannot be recognized independently. It is always subordinate to the species. 209.149.113.5 (talk) 20:34, 8 June 2017 (UTC)[reply]

and specifically for Canis familiaris vs. Canis lupus familiaris see Dog#Taxonomy. Dr Dima (talk) 21:06, 8 June 2017 (UTC)[reply]

The basic rule is that all members of a singles species share the same binomial - so all lions are Panthera leo (always use a capital letter for the genus). Sub-species are considered to show variation within the species, but not such as to justify them being labelled as separate species. So for the lions the main differences are in the size and shape of the mane, but many current lions are probably hybrids of different sub-species, and there is uncertainty about just how many different sub-species there really are.

The problems arise with groups like the wolf/dog/dingo. Taxonomists are clear that the dog is a domesticated form of wolf, and the dingo may be too, though that is less certain. What is debated is whether dogs and wolves have now diverged so far that they should be considered as separate species - so is the dog Canis lupus familiaris, or Canis familiaris. If you conclude that they are still the same species, then Canis lupus includes them all. If you conclude otherwise, then they each have their own binomial, sharing only the generic name. That is not an exception to the rule - just a case where there is uncertainty about how the rule should be applied. Wymspen (talk) 21:43, 8 June 2017 (UTC)[reply]

My understanding of the biological species concept is that it works like this: suppose you have two islands, A and B, and you go on a tranquilizer darting spree and come back with 10 animals of each sex from each island, and you let them all loose in an enclosure with a suitable environment. If the animals freely breed with each other, so that in a few generations most are descended from both islands, they would be the same species. If just a few under forced circumstances interbreed, like if you put one male from A and one female from B in a cage, and produce offspring, then they are different species and the offspring are hybrids. Hybrids often work only in one direction (Haldane's rule) but that isn't mandatory for the definition - they might breed both ways, but if they don't do so freely in a natural-like environment where both species are present, then that doesn't make them the same species. If they are the same species, but you can look at one of the 40 original animals and tell which island it came from, then they are different subspecies. But... there are some caveats.

To begin with, there is no guarantee of transitivity: if A will interbreed with B and B will interbreed with C, A may not interbreed with C. See ring species.

The distinction between subspecies and landraces or just races seems poorly drawn and perhaps political. I have the impression that subspecies are said to exist that are distinguished by little more than molecular markers - like any ancestry - for purposes of conservation, though I should disclaim I haven't looked into these issues carefully enough to be sure.

Environmental changes can cause two species to hybridize widely that would not have done so before. (this covers some examples) Under those circumstances the prevalent "species" level can quickly change. Wnt (talk) 01:39, 9 June 2017 (UTC)[reply]

Choosing between 3, 4, or 5 digit long chunks

I got a bunch of 15 digit player ID numbers that I need people to write down for future reference. I want to break down the number into either 3, 4, or 5 digit long chunks so that it's easier to communicate over the phone and in person. In other words, there are three possible formats:

1. XXX-XXX-XXX-XXX-XXX

2. XXXX-XXXX-XXXX-XXX0 (extra 0 for padding)

3. XXXXX-XXXXX-XXXXX

Has there been any scientific research done on which of these formats is faster/easier/more accurate for people to communicate with? Scala Cats (talk) 21:50, 8 June 2017 (UTC)[reply]

Best I could find is THIS. Only deals with phone numbers and lists different formats by country with varying justification. 64.170.21.194 (talk) 23:14, 8 June 2017 (UTC)[reply]

The Magical Number Seven, Plus or Minus Two would be an interesting read.--Jayron 32 00:45, 9 June 2017 (UTC)[reply]

I'm surprised that article doesn't list the criticism. That study was heavily American-centric. The "7" came from Americans being trained to memorize 7-digit phone numbers. When the study was repeated in other countries, the magic number changed. I doubt it pertains to anything anymore since people don't memorize phone numbers. They just just pull up names in a contact list. 209.149.113.5 (talk) 14:55, 9 June 2017 (UTC)[reply]

Just an observation: in France, phone numbers are commonly broken into 2-digit groups. Because of the way numerals in French are formed, this means that a number like "97-16-51-72" is spoken like "4-20-10-7-16-50-and-1-60-12"! It really is a matter of what people are used to. --69.159.63.238 (talk) 20:35, 9 June 2017 (UTC)[reply]

Go with the groups of 3. It divides into 15 nicely and is easy to read. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:11, 9 June 2017 (UTC)[reply]

Most credit/debit card numbers are 15 digits long. They add one extra checksum digit to make it 16 and break it into groups of 4. Why not use a checksum like that? It will help ensure all the digits are correct. — Preceding unsigned comment added by 71.85.51.150 (talk) 01:17, 10 June 2017 (UTC)[reply]

Specifically, they commonly use the Luhn checksum. (Hmm, I had to pipe that link. That should be a redirect. Should be a redirect. Anyone care to add it?) --69.159.63.238 (talk) 05:21, 10 June 2017 (UTC)[reply]

Done, thanks for noting it. Nil Einne (talk) 13:49, 10 June 2017 (UTC)[reply]

Thanks. --76.71.5.114 (talk) 23:17, 10 June 2017 (UTC)[reply]

I imagine the need for a checksum depends on the application - I mean, if there is nothing wrong with the person just looking up the number and trying again, why bother making him learn it? Given latitude, I'm thinking the nicest way to code the number might be to use some dictionary (this is the most common 10,000 words according to Google...). (You might have to trim this list and add a few to avoid collisions, or else capitalize first letters or require spaces - TherapistISandy) For example, "97-16-51-72" mentioned above would be "scoop flexibility". But a company would hate this lest it say something "politically incorrect"... and bullying always trumps efficiency and reliability. Wnt (talk) 16:31, 10 June 2017 (UTC)[reply]

My first thought was also using a dictionary, but unfortunately my player base is international and there's no good trans-lingual dictionary scheme out there (or at least I couldn't find one). Scala Cats (talk) 17:55, 10 June 2017 (UTC)[reply]

They wouldn't have to be the same words, would they? You could have a player choice at the time the number is given between English, French, Dutch, whatever, and so long as you could find unencumbered or licensable dictionaries for each, you could translate the same numbers into code phrases with entirely different meanings in each language. (For bilingual players they might flip back and forth and see which phrase is easier to remember!) Wnt (talk) 18:28, 10 June 2017 (UTC)[reply]

June 9

If there are more Na+ ions in the extracellular space, then will raw red meat taste salty?

Disregard the possibility of catching a foodborne illness. Will raw red meat taste salty? 50.4.236.254 (talk) 03:44, 9 June 2017 (UTC)[reply]

meat has lots of sodium to begin with apparently? 01 64.170.21.194 (talk) 04:49, 9 June 2017 (UTC)[reply]

Ever tasted blood? Abductive (reasoning) 05:51, 9 June 2017 (UTC)[reply]

Raw beef isn't bloody. It's myoglobin from the muscle tissue itself. --Jayron 32 05:53, 9 June 2017 (UTC)[reply]

"specifically in the red blood cells. In humans, myoglobin is only found in the bloodstream after muscle injury. It is an abnormal finding, and can be diagnostically relevant when found in blood".... right.. no blood... 64.170.21.194 (talk) 22:29, 9 June 2017 (UTC)[reply]

You guys are confounding myoglobin with electrolytes. It is the electrolytes that are perceived as salty. And there nearly the same levels of electrolytes everywhere in the body. Abductive (reasoning) 17:53, 11 June 2017 (UTC)[reply]

CG and crosswinds

How does a forward CG affect crosswind takeoffs and landings in a taildragger (not necessarily just the Electra 10-E, but any taildragger like for example a DC-3 or a Ju-52)? 2601:646:8E01:7E0B:4F8:7AED:9CA5:90AA (talk) 06:22, 9 June 2017 (UTC)[reply]

Anyone? Come on, I'm sure there's at least one pilot on here who knows this stuff! 2601:646:8E01:7E0B:E957:E363:9DD1:1743 (talk) 02:51, 12 June 2017 (UTC)[reply]

Is there a term for functional groups that are displaced during electrophilic substitution reactions?

I think the term leaving groups is reserved for functional groups that are displaced during nucleophilic substitution. OrganoMetallurgy (talk) 18:00, 9 June 2017 (UTC)[reply]

Electrofuge. DMacks (talk) 19:17, 9 June 2017 (UTC)[reply]

Electrofuges are a kind of leaving group; I've added IUPAC references to that effect in that article. Wnt (talk) 16:19, 10 June 2017 (UTC)[reply]

Thanks. I've been terribly confused about that. OrganoMetallurgy (talk) 18:02, 10 June 2017 (UTC)[reply]

I have the vague sense that a leaving group is simply a group that is "happy" with the structure and charge it ends up with, whatever the charge (or lack thereof) may be. So H+ and Cl- are good leaving groups - H- and Cl+, not so much (though I think the first does happen, and I'd be afraid to say the second is impossible...). Wnt (talk) 18:31, 10 June 2017 (UTC)[reply]

A hyride leaving group is common in several sorts of reactions, but the only ones I can think of involve it transferring directly as a nucleophile onto some other substrate rather than merely becoming solvated (Cannizzaro reaction and some biological dihydroquinone oxidations, or even less distinctly Oppenauer oxidation). I wonder what the mechanism is for the formation of the I⁺ (-like reactive intermediate) in the "I₂+HIO₃" electrophilic halogenation protocol? DMacks (talk) 20:29, 10 June 2017 (UTC)[reply]

Thanks for cleaning up the defs! DMacks (talk) 20:29, 10 June 2017 (UTC)[reply]

June 10

Feynman Lectures. Exercises PDF. Exercises 7-1...7-11

I have a general question. Feynman at the end of Section 7-4 describes the mechanism of tides. He says that centrifugal force balances gravitation force of the moon at the center of the earth. I assume we can prove that for moon free fall acceleration (at the distance 384 400 km) and centrifugal acceleration we can replace the earth by one point:
* for the centrifugal force:
we can divide the earth into 1 kg bricks and sum up the forces applied;
the centrifugal acceleration ω²R is linearly dependent from R , its x-projection is same for each section of the earth , its y-projections cancel each other png
during summation we see that lowering the centrifugal force on near side of the earth is just compensated by the growth at the far side of the earth. So the sum will not change if we replace all the forces by the mean force -- the force at the center.
* for the gravitation force:
for large distance from the moon (384 400 km) and for relatively small earth diameter (12 800 km) the change in the moon field (moon free fall acceleration) is almost linear (3.4×10^-5 m/sec² on near side of the earth , 3.3×10^-5 at the earth center, 3.2×10^-5 at the far side )png . Neglecting moon's field direction, the same analysis permits to change all the forces by the mean force and collect all mass of the earth in a single point.

But from such reasoning I still can't see why do the mean forces balance each other. Is it because the Earth would otherwise have come down from the orbit (no more equilibrium in rotating reference frame)? Is such reasoning correct? Username160611000000 (talk) 12:54, 10 June 2017 (UTC).[reply]

I might be misunderstanding, but I think you want the shell theorem. The idea is that a spherical shell of Earth of uniform density will orbit and attract like a point mass at its center. Note that since the Earth is not a perfect sphere or perfectly uniform in density at a given depth, your premise should not be perfectly true. Wnt (talk) 16:33, 10 June 2017 (UTC)[reply]

Feynman explains "shell theorem" later [2] . According to him a spherical body and a point with equal mass generate identical fields. But nothing is said about objects affected by that field. In this problem the moon can be thought as a point. But this does not change either the formulas or the drawings. If Feynman gives this problem in Lecture 7, then we need not "shell theorem" to explain the phenomenon. Actually the tidal effect itself shows that earth cannot be considered as a point (it can be considered as point approximately and only for collecting the force, but not for further explanation ).
So no, "shell theorem" is out of place. Username160611000000 (talk) 17:25, 10 June 2017 (UTC)[reply]

This lecture is simply applying Newtons' law of action-reaction by balancing two forces, the reactive centrifugal force (which is not to be confused with fictitious centrifugal forces that are due to rotating reference frames) and the gravitational force that are said to be acting on the masses. That is all. This is not the modern view, but it is a traditional treatment of the problem. BTW, when I was introduced to the term "centrifugal force" I understood it in the sense of the reactive centrifugal force that acts on a string (or the other mass as the case here). Strings, flywheels and spinners are always under tension due to it. To make things even more interesting, the last section of the reactive centrifugal force article points out that with the gravitational two-body case (such as that is being considered here), the reaction to the centripetal force is also a centripetal force. So there you go. I hope that helps. --Modocc (talk) 19:51, 10 June 2017 (UTC)[reply]

@Modocc: BTW, when I was introduced to the term "centrifugal force" I understood it in the sense of the reactive centrifugal force that acts on a string (or the other mass as the case here).
First, it doesn't explain then why do both forces balance in the center of the earth, and not somewhere else (according to the rules we can move a vector along an axis). Second, these forces (gravitational attraction from the moon on the earth and reactive force from the earth on the source) are applied to the different objects. Yes, we can add forces on one axis, but I'm not sure that in this case it is possible.
Username160611000000 (talk • contribs) 04:30, 11 June 2017 (UTC)[reply]

OK. Reading further, I see he says "What do we mean by “balanced”? What balances? If the moon pulls the whole earth toward it, why doesn’t the earth fall right “up” to the moon? Because the earth does the same trick as the moon, it goes in a circle around a point which is inside the earth but not at its center." So he means any system's mass center. The common mass center between the Earth's water and the rest of it is its center in this case. Both of these masses are held in place by gravity as they rotate around the Earth's center. This also means that both masses pretty much happen to trace the same orbit around the Earth-Moon barycenter, more or less. --Modocc (talk) 04:57, 11 June 2017 (UTC)[reply]

My original questions were:
1 Are the forces balanced at the center of the earth and how it could be explained?
2 If the forces are balanced at the center, then can it reason the tidal effect as consequence?
Using very accurate plotting I've found that the total effect of both forces gave a lifting acceleration over the earth intersection by the moon orbit plane PNG. The lifting acceleration is a bit smaller on the Y-axis . Image can answer question 2 ( doubtful as it seems must be not 2 high tides , but one ecliptic tide instead). But I'm still in suspense about question 1. Are my arguments at the beginning correct?
Username160611000000 (talk) 07:56, 11 June 2017 (UTC).[reply]

I had an additional question. According to [3] the typical tidal range in the open ocean = 0.6 metres. According to assumption that water pressure must be equal
ρg_lowh₀=ρg_high(h₀+0.6)
∴ g_low / g_high = 1 + 0.6/h₀.
Putting average ocean depth 3000 m we have g_low / g_high =1.0002. But according image at earth equator g_low / g_high = (9.8 - 3.4×10^-5) / (9.8 - 4.3×10^-5) = 1.000001.
Username160611000000 (talk) 11:06, 11 June 2017 (UTC)[reply]

I think you're way off track there. You seem to be assuming that water will compress in proportion to the gravity on it, but it won't. And I think you're assuming the water only gets higher and lower based on this compression or expansion from the bottom of the ocean. But this isn't how tides work - the point with tides is that the ocean surface gets tilted ever so slightly from horizontal - relative to the combined Earth-Moon gravity field, that is - and the water pours downhill. Now earth tides may indeed work that way, but that is based on compression of thousands of km of rock rather than just the ocean, and the rock can't flow much ... or can it? I just realized I have no idea how much rock can wiggle if you wiggle it ever, ever so slightly. Stuff like Young's modulus is linear.... hmmm... actually the earth tide article seems to suggest the Earth does flow on that scale, but then why so little...? Wnt (talk) 13:02, 11 June 2017 (UTC)[reply]

I'm still confused why you don't think the shell theorem is relevant. At the beginning you said that the y-components (which I assume are perpendicular to the Earth-Moon axis) cancel, and that the near and far sides "almost" average out. Well, as far as I know, the near and far sides do average out if you look at a spherical shell, taking into account that there is more of the sphere far away than close to a given point. So you're looking for it but I don't think your math will work out very easily unless you actually split up your bricks in spherical shells. Wnt (talk) 12:53, 11 June 2017 (UTC)[reply]

What do people mean by "reversing diabetes/CVD"?

Does it mean that the patient no longer has to depend on medications or be hospitalized or live with some kind of physical ailments (blindness, brain damage)? Or does it mean that the person no longer has to be restricted to diabetes-friendly food? By the way, what happens if a normal healthy person eats food made for diabetics? Is diabetic food safe for the non-diabetic? 50.4.236.254 (talk) 17:41, 10 June 2017 (UTC)[reply]

Diabetic foods are generally safe for everyone. (Caveat: some varieties may be sweetened with weird sugar substitutes that cause some digestive unpleasantness, but if so, the diabetics feel the same)

Putting type II diabetes into remission by weight loss and other therapies does happen; it's largely a matter of reversing insulin resistance. It's important to note though that diabetes is a common condition and many people, even those who don't have it, live close to the edge of it with standard Western diets. There is some evidence to suggest that even prediabetes thought not to be so bad ... is so bad. For example, prediabetics tend to prefer diet soda by taste, presumably having to do with higher blood sugar, and this study found a correlation between that and other serious problems that was not accounted for by diagnosed diabetes. Unless one goes for what seem like overblown theories about aspartame, anyway... Wnt (talk) 18:37, 10 June 2017 (UTC)[reply]

Has anybody done research on the eating habits of African, Asian, South American, and Eastern European immigrants in a Western country and whether they have the same obesity prevalence as Westerners? With obesity on the rise and so many people trying new things, just how common/prevalent is the Standard Western Diet? 50.4.236.254 (talk) 19:16, 10 June 2017 (UTC)[reply]

Not quite what you were asking but the rate among Inuit and First Nations in Canada is growing after the adoption of a western diet. See First Nations and diabetes, Inuit Type 2 diabetes gap worsens and Diabetes - First Nations & Inuit Health. CambridgeBayWeather, Uqaqtuq (talk), Sunasuttuq 00:09, 11 June 2017 (UTC)[reply]

Grey hair

I've noticed numerous, isolated white hairs on people with otherwise dark brown or even black hair. Is the presence of such hairs, in any sense, distinct from greying, where, I believe, many more hairs have lost pigmentation, but only partially, and as such are grey rather than white?--Leon (talk) 17:53, 10 June 2017 (UTC)[reply]

“

Each individuals hair colour is determined by the particular pigment they produce (called melanin - the same stuff in your skin that makes you tan).

As the body ages this pigment (produced by the melanonocytes - cells that reside in the hair follicle) is produced less and less, until the hair is no longer coloured, and appears grey. This is unique to each individual because it is a genetic (and therefore highly heritable) trait. Because it is in no way linked to mortality there is no selection pressure against greying hair. The reason that the pigment is not longer produced is the gradual depletion of the stem-cell pool with age. This is common to many tissues, hair follicles being just one. As the 'pool' of stem cells is depleted, the melanocytes are no longer replaced as frequently, and thus less pigment is produced as we age.

”

— Luke, Biology Stack Exchange

50.4.236.254 (talk) 18:16, 10 June 2017 (UTC)[reply]

I take issue with the statement "Because it is in no way linked to mortality there is no selection pressure against greying hair". A trait does not need to be linked to mortality to be subject to selection. For instance, it is quite plausible that grey hair has a negative effect on sexual attractiveness, and in that way is selected against. But one can also think of possible advantages: older looking individuals are seen as less of a threat or their opinions are more respected; this might benefit the grey haired individual directly or benefit their family members. Note that in our close relative the gorilla, the grey hair of silverbacks is clearly an adaptation concerned with signalling maturity and dominance. Note also that greying in old age seems to be a trait shared with other mammals, such as dogs. The loss of pigment in older humans might indeed just be an incidental side effect of no selective value, but my own hunches would be that it is not selectively neutral, and that it has some unrecognised positive selective value in signalling age.

Some recent discoveries about the genetics of grey hair may be of relevance to the original question: http://www.ucl.ac.uk/news/news-articles/0316/010316-first-grey-hair-gene-discovered . Jmchutchinson (talk) 19:08, 10 June 2017 (UTC)[reply]

Most humans become grey-haired only after they have reproduced, thus selective pressure against greying is minimal. Roger (Dodger67) (talk) 09:27, 11 June 2017 (UTC)[reply]

Sperm production does decline with age but not enough to make most men infertile at the age at which they would have grey hair (http://www.reproduction-online.org/content/70/1/211.long). The extent to which grey-haired men have the opportunity to mate with younger (i.e. fertile) women no doubt varies between cultures. Another important point is that the traits of post-reproductive individuals of both sexes are still subject to natural selection through their effect on the ability to care for grandchildren and other relatives (see Kin selection). Jmchutchinson (talk) 10:31, 11 June 2017 (UTC)[reply]

Star trooper man, I question your assumption that "grey hair" is due to individual hairs partially losing pigmentation with age. The article sections Human hair color#Gray and white hair and Human hair color#Aging or achromotrichia appear to corroborate my own experience (being 60) that individual hairs (ignoring bleaching by sunlight or chemicals) switch from growing with natural colour to growing white/colourless fairly quickly: the "greying" of the overall head of hair is due to an increasing proportion of white/colourless hairs amongst the still-pigmented.

In my own case, which I assume to be typical, a very few individual hairs have with age started to grow markedly darker, but so few that they do not effect the overall appearance. Up to now, I have not encountered any explanation for this latter phenomenon. {The poster formerly known as 87.81.230.195} 2.217.208.38 (talk) 09:48, 11 June 2017 (UTC)[reply]

My assumption was actually that what I described doesn't happen, that is, the person who claimed (to me) that the processes were distinct—implying that the latter process exists—was wrong. I have not observed this in people's hair.--Leon (talk) 17:53, 11 June 2017 (UTC)[reply]

Is Zaus gland considered as a lacrimal gland?

Is Zeis' gland considered as lacrimal gland? Based on this picture it seems that it is, but I'm not sure how authorized or correct it is. 93.126.88.30 (talk) 22:52, 10 June 2017 (UTC)[reply]

Judging by this abstract ( [4] ) I think not. I didn't check Sci-Hub for it, but it probably explains further. I think Zeis' gland secretes lipid while lacrimal gland secretes mostly saline solution, but I haven't looked into it enough to be sure. Tear film for the eye is really sophisticated technology at the biological level and shouldn't be underestimated. Wnt (talk) 00:28, 11 June 2017 (UTC)[reply]

Yellow mercuric oxide

When I were a lad, minor eyelid infections (styes) were treated with an ointment of "yellow mercuric oxide" (presumably mercury(II) oxide, HgO), which was sold over-the-counter. But the last time there was a need, I couldn't find the stuff. There was an ointment called Stye (trade name; we don't seem to have an article), which if memory serves used to have YMO, but it seemed to have been reduced to a lubricant with no antibacterial component.

Searching around, I find a paper that recommends it for a very particular condition, phthiriasis palpebrarum, not for styes in the usual sense. It doesn't seem to be available for pharmaceutical sale in the United States.

Presumably it was banned at some point, at least for over-the-counter sales? I didn't see anything specifically saying that, but it seems like the natural guess. When did that happen? Or was it something else, maybe product-liability concerns? --Trovatore (talk) 23:08, 10 June 2017 (UTC)[reply]

Hum. Wonder if you're so old that your birth certificate is in Latin. Banned a long time ago. See your ~~quack~~ Doctor. If he thinks it needs treating it will be with an antibiotic. Aspro (talk) 23:18, 10 June 2017 (UTC)[reply]

Oh, I don't have a need at the moment. I was reminded of it when clicking around in reaction to the question above, about "lacrimal glands". Do you have details on the banning, with particular attention to the United States? --Trovatore (talk) 23:23, 10 June 2017 (UTC)[reply]

Apparently this is Pagenstecher's ointment. [5] A 1990 study called it safe and effective for treatment of bacterial blepharitis of the eyelid. Apparently in 1983 the FDA published a Tentative Final Monograph banning it from over the counter use on the basis that patients might have a more serious infection, therefore must be sent to see a doctor to find out if it is only trivial. [6] As always, medicine is a racket; it's only about the money. That said, this is true for both sides, and many sorts of blepharitis often respond nicely to warm wet compresses... [7] ... the risks of mercury are probably exaggerated, but still, of various drugs unjustly banned and restricted, this one seems less indispensable than some. Wnt (talk) 00:50, 11 June 2017 (UTC)[reply]

Well, there's no longer any need for it -- antibiotics work just as well, and are safer (no need to worry about chronic toxicity). 2601:646:8E01:7E0B:E957:E363:9DD1:1743 (talk) 06:38, 11 June 2017 (UTC)[reply]

I used the original "Golden Eye Ointment" for many years after it went off the market in the UK, and found it more effective than its modern (1992) replacement and other modern OTC ointments containing dibromopropamidine isethionate, with only one or two applications needed for minor infections (though I don't doubt that a properly prescribed appropriate stronger antibiotic might be more effective, but wastes a lot of time in obtaining). I wish I hadn't thrown it out, even though it was many years out of date. There's probably more mercury poisoning risk from eating fish! Dbfirs 08:01, 11 June 2017 (UTC)[reply]

Yeah, my memory is that it worked really well. If you've ever had one of these things, you know you want it gone pronto. The reason the FDA gave, per Wnt, is unbelievably insulting. If that's the only reason, we should lobby to get it back in the stores ASAP. --Trovatore (talk) 08:42, 11 June 2017 (UTC)[reply]

Unfortunately, I don't think we'd get anywhere with the US or UK authorities. The words "contains mercury" set off warning bells for an automatic refusal these days (almost as alarming as "contains asbestos"). ~~Is the ointment available elsewhere in the world? Can we import it? Can we make it?~~ Sorry, don't answer that. It was not intended as a request for medical advice. Dbfirs 11:59, 11 June 2017 (UTC)[reply]

RfC Announce: Wikimedia referrer policy

In February of 2016 the Wikimedia foundation started sending information to all of the websites we link to that allow the owner of the website (or someone who hacks the website, or law enforcement with a search warrant / subpoena) to figure out what Wikipedia page the user was reading when they clicked on the external link.

The WMF is not bound by Wikipedia RfCs, but we can use an advisory-only RfC to decide what information, if any, we want to send to websites we link to and then put in a request to the WMF. I have posted such an advisory-only RfC, which may be found here:

Wikipedia:Village pump (policy)#RfC: Wikimedia referrer policy

Please comment so that we can determine the consensus of the Wikipedia community on this matter. --Guy Macon (talk) 23:28, 10 June 2017 (UTC)[reply]

June 11

Could a dog be trained ...

Could a (police/military) dog be trained to pick out an awake person from a group of asleep people or vice versa?Naraht (talk) 03:39, 11 June 2017 (UTC)[reply]

Not reliably -- people don't smell any different when they're awake than when they're asleep, and the one thing on which dogs beat people hands-down is perceiving smells which are undetectable to humans. So if someone is really good at pretending he/she is asleep (like me -- I have very long eyelashes, so I can pretend to have my eyes closed when in fact they're slightly open), then he/she can fool a dog just as easily as a human. 2601:646:8E01:7E0B:E957:E363:9DD1:1743 (talk) 06:36, 11 June 2017 (UTC)[reply]

How do you know? ←Baseball Bugs ^{What's up, Doc?} carrots→ 07:07, 11 June 2017 (UTC)[reply]

How do you know if people smell different when they're asleep? 2601:646:8E01:7E0B:E957:E363:9DD1:1743 (talk) 07:57, 11 June 2017 (UTC)[reply]

I don't. And neither do you. But a dog might be able to tell. Dogs have a much better sense of smell than humans do. ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:35, 11 June 2017 (UTC)[reply]

The above response both assume the person is trying to pretend to be asleep. That's not how I read the Q. Say you want a dog to go into a house, and get the attention of whoever is awake in there, meaning eyes open and maybe even up and about, and bring them out. They should be able to be trained for that, yes. Why would we do that ? Say we have a camera installed in a house where a hostage is being held, and see that the hostage taker has fallen asleep (presumably after a prolonged siege), but see that the hostage is awake. They might be scared to attempt escape on their own, but if we could send in a police dog to pull them out, that might resolve the situation peacefully. StuRat (talk) 08:53, 11 June 2017 (UTC)[reply]

OP, could you elaborate on what you mean? If you mean, could a dog tell the difference between someone really asleep and someone only pretending to be asleep, I would think it's possible, but it would probably depend on how well the dog knew the people involved. Your heart rate and breathing patterns would be different, probably other stuff like circulation and other processes, at least some of which would be detectable by a trained dog. The idea that a dog can detect cancer has received a lot more publicity than verifiable research (we have it grouped with other pseudoscientific beliefs), but there's no denying that dogs can be very observant and trained to detect quite minute changes. Matt Deres (talk) 14:38, 11 June 2017 (UTC)[reply]

OP here. To make the question more clear, you have 12 people lying on cots, 11 asleep and 1 awake but faking asleep or conversely. 1 asleep or 11 awake but faking asleep.Naraht (talk) 18:41, 11 June 2017 (UTC)[reply]

Using numbers to make something more believable

I often see big headings that say, "Researchers say..." or "Scientists say..." or mention some kind of percentage or statistical information without really providing any source. It seems to me that the popular impression of science is that science is the ultimate source for knowledge, and nothing beats the scientific knowledge, so if anyone makes a claim appear like a formal scientific finding, then the claim is readily believed. Similarly, in résumé-building workshops, it is advised that the résumé should always use numbers to make the résumé stand out from the rest. Is there any support for the use of numbers as a rhetorical strategy? 50.4.236.254 (talk) 03:54, 11 June 2017 (UTC)[reply]

You may find this of interest. ←Baseball Bugs ^{What's up, Doc?} carrots→ 07:06, 11 June 2017 (UTC)[reply]

In statistics, there are ways to tell if a poll is accurate. You would need to see the actual Q's asked, to make sure they are unbiased, so "Who will you vote for, candidate X or Y ?" vs "Will you vote for the liberal spend-o-crat or the true patriot ?". Where the Q is asked is also important, so no opinion websites, for example, but rather someplace neutral. And the number of people polled is critical, with 1100 being a good minimum to get accurate results. Also, the percentage of people asked who respond is important. If only 1% respond, you may get highly inaccurate results. And to get a high response rate you probably need to pay people (not much, just enough to make it worth their time). StuRat (talk) 08:47, 11 June 2017 (UTC)[reply]

In lying, use of numbers is also important, as being able to produce and repeat what appears to be a reasonable number makes it seem as if it's a fact. On the other hand, if the number constantly changes, such as the infamous number for the "list of foreign agents who have infiltrated the US government", that Joseph McCarthy always claimed to have, but could never produce, then the lie isn't so believable. Big, round numbers, such as Trump's claim that 5 million voters voted fraudulently in the US Presidential, are also suspect, as are one-sided numbers, here being his claims that all the fraudulent votes were for Hillary, and none for him. Had he claimed to have proof that 932 fraudulent votes were cast for Hillary and 127 for him, with 13 to other candidates, it certainly would have been a more believable lie. StuRat (talk) 09:14, 11 June 2017 (UTC)[reply]

Lies, damned lies, and statistics is a phrase describing the persuasive power of numbers, particularly the use of statistics to bolster weak arguments. The cited article discusses the source of the phrase. Blooteuth (talk) 12:18, 11 June 2017 (UTC)[reply]

One of my favorite books of all time is Huff's How to Lie with Statistics. It's a bit old, but is now more applicable than ever. Shock Brigade Harvester Boris (talk) 15:29, 11 June 2017 (UTC)[reply]

Nuclear reactor

Is it possible to disable an operating nuclear reactor (not like Osirak, which was destroyed before it could be put into operation) without causing a Chernobyl-scale radioactive spill? For example, say that we needed to put Iranian or North Korean reactors out of action -- how could that be done? 2601:646:8E01:7E0B:E957:E363:9DD1:1743 (talk) 06:44, 11 June 2017 (UTC)[reply]

See here for a method to disable nuclear weapons. Count Iblis (talk) 08:24, 11 June 2017 (UTC)[reply]

@Count Iblis: Great reference! Man, I've been speculating about blowing up nuclear bombs with "neutrino lasers" for a long time, but I never imagined there was actually a paper. That said, well ... the paper is about blowing them up - though perhaps only at 3% fizzle yield - which is not what the OP asked for. (While I'm at it, you wouldn't happen to have seen anything suggesting that there might be vastly more compact and efficient neutrino detectors than is publicly known, allowing real-time mapping of all nuclear weapons...?) Wnt (talk) 13:15, 11 June 2017 (UTC)[reply]

Nuclear reactors come in many flavors. Draining the water would safely shut down many U.S. reactor as in some designs, the water is needed to increase the probability of neutron collisions with atoms. The question is why? Nuclear reactors can supply material for a bomb but isn't a bomb itself. Centrifuges create the concentrations necessary for a bomb. The best bet is to prevent the reactors that create bombs material from coming online. In the 1980's Israel bombed Saddam Hussein's nuclear reactor site in Iraq (see Operation Opera - Iran had previously attempted to bomb the same potential breeder site.) Pre-emptive military or diplomatic intervention that prevent them from being active is likely the only successful means of stopping proliferation. --DHeyward (talk) 08:31, 11 June 2017 (UTC)[reply]

Note that you have two very different Q's there. If we leave out the last sentence, the answer is yes, an emergency shut-down can be used to disable the reactor. There should be no immediate release of radiation, if done correctly, but there is the need to remove the fuel from the reactor core and store it somewhere safer, eventually. This process is called decommissioning. See [8].

However, when you add in those examples, it's clear you are talking about doing so to an enemy nuclear reactor, of a rogue nation, during a war (or at least a military action). That may well make it impossible to do so without the release of radiation. The nation under attack may even intentionally release radiation, much as Iraq set oil wells on fire when it was under attack, if the winds will then carry the radioactivity into enemy nations. StuRat (talk) 08:38, 11 June 2017 (UTC)[reply]

Most reactors are now LWR. It would be very unwise to drain the water from them! Fission may cease but the decay products are still producing heat and lead to a melt down. This is what happened at Fukushima where all three cores of the fueled reactors melted. If the attack also puts the gantry used for de-fueling out of action and rupture the cooling ponds... well I suppose you can guess the rest. Best time to attack a reactor is to wait until it has been completed but not yet fueled. The British did this in WWII. They waited until the massive U-Boat pens had been finished before finishing them off with a just few of Sir Barns Wallace's earthquake bombs. Another option is to inject a worm into their computer control system. That might provide a breathing space for negotiations – Jaw, jaw is better than War, war. Aspro (talk) 15:19, 11 June 2017 (UTC)[reply]

Barnes Wallis is the correct spelling of his name. Akld guy (talk) 19:35, 11 June 2017 (UTC)[reply]

Suppose, though, that we missed the chance to take out the reactors before they were fueled, due to the incompetence or outright connivance with the enemy of past presidents (as is indeed the case in reality) -- are you saying that it is no longer possible to take them out without causing a second Chernobyl? (BTW, I'm not talking about LWR reactors -- these are not well-suited for making plutonium for bombs, so the reactors in question would be either of the heavy-water, graphite-moderated or fast-breeder type.) 2601:646:8E01:7E0B:E957:E363:9DD1:1743 (talk) 00:43, 12 June 2017 (UTC)[reply]

Anxiety as "the great imitator"

Why is it that anxiety is known as "the great imitator" and often misdiagnosed by clinicians for more serious medical conditions such as heart attacks, anaphylaxis etc. 82.132.237.181 (talk) 08:59, 11 June 2017 (UTC)[reply]

Symptoms such as increased pulse rate and blood pressure certainly are shared with a number of other medical conditions. Also, many medical conditions can produce anxiety, so it's not always clear if the anxiety is the cause or just a symptom. StuRat (talk) 09:20, 11 June 2017 (UTC)[reply]

I would have thought clinicians would be able to tell the difference by running tests though? Or do they simply assume the worst case scenario to be risk averse? 2A02:C7D:B916:4200:30E9:C9CB:A755:FD5 (talk) 11:08, 11 June 2017 (UTC)[reply]

Many diseases lack a simple, definitive test. StuRat (talk) 15:21, 11 June 2017 (UTC)[reply]

Only patients themselves misdiagnose anxiety as heart conditions. Clinicians never do this. --AboutFace 22 (talk) 18:14, 11 June 2017 (UTC)[reply]

I was hospitalized about 15 years ago for a significant period, and reported to the nurse I thought I was having a heart attack. They gave me a shot of valium in my IV and it went away. I told the nurse I didn't feel worried, but she said one doesn't need to have a belief to have a panic attack, and that they are much more common than one might think. μηδείς (talk) 01:00, 12 June 2017 (UTC)[reply]

Tongue-in-cheek scientific studies

Wikipedia has a page on comparing apples to oranges and mentions two "tongue-in-cheek" scientific studies. First of all, what makes a study tongue-in-cheek? What if the authors were really serious about the experiment but the situation is so trivial that it is ludicrous? Is laughter or the expectation of laughter in empathetic individuals the real reason why something is perceived to be tongue-in-cheek? Second of all, are there more studies that are like this? Third, how does a professional scientist find the time to do studies like this when grant-funding relies on how relevant or important the study is? Is such work primarily done in one's spare time on the side, just using the organization's resources or personal resources, or is such work done by a tenured professor who is very secure about his livelihood? 50.4.236.254 (talk) 11:19, 11 June 2017 (UTC) I added a wikilink to the subject page. Blooteuth (talk) 12:43, 11 June 2017 (UTC)[reply]

The first was published in the Annals of Improbable Research (not to be confused with the Journal of Irreproducible Results), in other words, a comedic forum. The other ... well, it also seems to be in some sort of comic section, but it's a bit more mysterious to me: [9] British Medical Journal is ordinarily serious, and while British journals tend to print remarkable things on April Fools' Day, I don't know why this would come out then. But you can see the next article is no more serious in tone.

Also note that James E. Barrone, the author of the second study, is listed as surgeon in chief of a hospital and presented something similar at a surgical meeting. You know how bosses love their "icebreakers"; whatever Brahmins do is good and proper by definition. But also notice the date - 2000, which was a whole different era, one where people felt confident and free and didn't think that their existence was a sin against the capitalist order, meant to be remedied by their replacement by a machine, reduction to impoverishment, and eventual self-sacrifice on the altar of Huitzlopochtli, because there can be no remission without blood. There were actually people back then who thought that bullying was not the supreme essence of the social order, and who viewed it as some kind of aberration! Wnt (talk) 13:29, 11 June 2017 (UTC)[reply]

Great answer, thanks. Maybe could use a bit less WP:OR about Brahmins etc. Not that I think you're wrong per se, just that it's a bit off-topic. OP may also be interested in how explaining a joke kills it and perhaps our article on tongue-in-cheek (hint: it's the expectation and intention of humor that counts). Part of the idea is that humor is subjective, and it is indeed possible that I might think you are making a tongue-in-cheek joke when you may in fact think you are explaining something very important. Miscommunication happens, certainly much/all of the research linked at NCBI ROFL [10] is both fairly serious to some but fairly silly to others. It's not always clear to the general public what use and function a research program may have, and on what grounds it is justified. E.g. the famous treadmill for a shrimp [11] was commonly mocked by Fox News et al. but it's also good science and important work. See also this NPR piece on the politics of "silly" science [12] SemanticMantis (talk) 20:19, 11 June 2017 (UTC)[reply]

I will just leave this here... --Guy Macon (talk) 20:25, 11 June 2017 (UTC)[reply]

Heat

If Miami is south of Huntington and both are in the Northern Hemisphere, then why is Huntington getting hotter weather than Miami? 32ieww (talk) 17:48, 11 June 2017 (UTC)[reply]

Wind, cool ocean nearby, and solar inputs. Abductive (reasoning) 17:57, 11 June 2017 (UTC)[reply]

Huntington where? Sagittarian Milky Way (talk) 20:33, 11 June 2017 (UTC)[reply]

Read Köppen climate classification. In short some landscapes have the ability to level out day and night temperature differences and other weather condition differences, some landscapes make weather conditions even worse. Arctic landscapes for example simply reflects huge parts of the sunlight while a Rain forest converts and even preserves it. --Kharon (talk) 23:09, 11 June 2017 (UTC)[reply]

Miami, being near the terminal end of a long peninsula, very much takes on the weather from the Atlantic Ocean and possibly from the Gulf of Mexico, when winds blow the weather across Florida towards Miami. Water temperatures rarely exceed 80 degrees F by much, since, when they do, hurricanes spawn which suck down cold air from the stratosphere to cool the water down. So, wind blowing over water below that temperature produces humid, but not terribly hot, air, which then blows across Miami. Of course, there is some solar heating of air directly over Florida, so on days with little wind, the temperature can rise considerably above 80°F, with the record being 100°F. The temperature is also limited on the low end, for the same reason, with the record being 27°F. This type of climate is common to both tropical and subtropical ocean islands, as well, but not arctic and antarctic islands, where the water can freeze in winter, and no longer warm the water that blows over it. StuRat (talk) 00:59, 12 June 2017 (UTC)[reply]

Diffusion potentials are created by the diffusion of 'very few ions'? meaning

I was reading that: "Diffusion potentials are created by the diffusion of very few ions and, therefore, do not result in changes in concentration of the diffusing ions.". What does it mean by "very few ions"? it means to denote the quantity or the types of the ions? 93.126.88.30 (talk) 17:52, 11 June 2017 (UTC)[reply]

If the context is the 70 mV membrane potential in human nerve and muscle cells, they mean relatively few ions. In other words, the ions that are being pumped or diffused represent a tiny, almost immeasurable fraction of the total ions present. Abductive (reasoning) 17:59, 11 June 2017 (UTC)[reply]

Thank you. Then it refers to the quantity. 93.126.88.30 (talk) 00:57, 12 June 2017 (UTC)[reply]

Please help identify my pine tree from photos. It looks like a White pine

Please help identify my pine tree from photos. It looks like a White pine. At other web sites, the male cones match my specimen, but on the Wkikipedia White Pine page the male cones are much smaller. Tree shape, needles, bark, female cones, and tree shape all appear to match.

18:10, 11 June 2017 (UTC)Miriamkilmer (talk) This is supposed to be a question, but the question link leads me here.

The British tree-spotters bible, Field Guide to the Trees of Britain and Northern Europe by Alan Mitchell, says for Pinus strobus:

Flowers and cone: Male flowers small 6mm ovoids, whitish, tipped bright cerise, on basal 3 cm of new shoot.

Foliage: Leaves in fives, 8-12 cm staying close together in bundles.

It looks to me as though it fits the bill, but its not a tree I'm really familiar with. Alansplodge (talk) 18:27, 11 June 2017 (UTC)[reply]

What's the difference between an ant colony, bee colony, and a human society?

From a newbie's perspective, they look the same. But are they? Or is that impossible to find out because everything is written from a human perspective, and it's just a matter of humans finding empathy in nonhuman things? 50.4.236.254 (talk) 21:08, 11 June 2017 (UTC)[reply]

Well, ants, bees and wasps are all members of the order Hymenoptera and are quite similar behaviorly. For example, the fact that male Hymenopterans are produced by unfertilized eggs has a profound effect on the social structure of nests/hives. Abductive (reasoning) 21:24, 11 June 2017 (UTC)[reply]

We have articles on ant colony, beehive, and human society. The OP may find our article at Eusociality helpful. Matt Deres (talk) 23:27, 11 June 2017 (UTC)[reply]

Many philosophers and economists tried and still try to argue Division of labour as an "natural ant colony" like concept adapted by humanity. Some even claim this to be a science. See Taylorism as example. These are simplifications ofcourse that in some cases greatly support an "ant colony" impression but every individal knows how far away he really is from being a drone, bee or ant, and thus how wrong these simplifications are. Such concepts are apriori far away from any empathy and therefor they can hardly promote empathy for ants, bees or other nonhuman beings. --Kharon (talk) 23:45, 11 June 2017 (UTC)[reply]

What's a "snow fruit"?

This page about Pitcairn Island [13] mentions a "snow fruit". What is that, botanically speaking? Equinox ◑ 23:04, 11 June 2017 (UTC)[reply]

Confirm from a 1951 L.A. Times article this was grown on the island and was an export at the time, as well as much later obviously in your photo. Alas, I'm not finding the phrase in www.pfaf.org , nor the most obvious sections of www.ncbi.nlm.nih.gov (they claim lots of hits everywhere, but always "quoted phrase not found" when I go to PubMed, Books, Gene etc. I'll admit I didn't try them all. Wnt (talk) 00:07, 12 June 2017 (UTC)[reply]

June 12

Why does water not have calories?

I'm trying to understand why water doesn't have calories and we can drink as much as we want without to be afraid of obesity. Would it be true if I'll say that just fats, carbs or proteins can have calories and all the rest substances don't hvae? 93.126.88.30 (talk) 01:00, 12 June 2017 (UTC)[reply]

Add alcohol to the list of things we consume with calories. Digestion produces energy by a type of slow combustion, so only substances which are flammable (once the water is removed) give us energy. Of course, we can't digest all flammable substances, so don't drink diesel fuel. StuRat (talk) 01:05, 12 June 2017 (UTC)[reply]

The calorie is a unit of energy. This energy is produced by oxidation (what StuRat calls "a type of slow combustion"). Since water cannot be oxidized (at least, not in this context), it has no calories. Shock Brigade Harvester Boris (talk) 01:13, 12 June 2017 (UTC)[reply]