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January 28

Why ketone "bodies?"

"Body" might refer to a living or dead human, or to a planet or visible object in space, such as "heavenly body," or "a body of works" or "the body of an aircraft"or" a body of clergymen." It might refer to "a wine with real "body"." Why is there this peculiar usage in combination with "ketone?"See Ketone bodies. OK, they are water soluble molecules. Ketones can be found in chemical laboratories, and they can appear in the human bloodstream as a result of diabetic problems resulting in Ketoacidosis. They are then called "ketone bodies." I would like to know why they are called "ketone bodies" as opposed to simply "ketones?" If ethyl alcohol is consumed as wine, beer, whiskey, etc, then ethanol is in the bloodstream as well. but it is not called "ethanol bodies." If adrenaline, prolactin, testosterone or insulin are released by glands and circulate in the bloodstream, they do not get "bodies" as a descriptor. Edison (talk) 02:23, 28 January 2017 (UTC)

I believe this is simply a historical description that has been continued out of tradition. Refs that say such invariably point out that they arent' evan all ketones (e.g. hydroxbutyric acid) but I'm not sure who first described them as "bodies". - Nunh-huh 02:34, 28 January 2017 (UTC)

Why not say the blood contains "carbon dioxide bodies," " glucose bodies", and "oxygen bodies?" "Ketone bodies" sounds like little creatures or objects getting pumped around in the circulatory system. Are there little globs of ketone, as this term suggests, or is it dispersed evenly throughout the circulatory system? Are they paying homage to some revered scientist with this odd and confusing usage? What is lost if we simply say "ketones" rather that "ketone bodies?" Oh "We've always done it the other and confusing way?" Puh-leeze! Edison (talk) 02:40, 28 January 2017 (UTC)

the "ketone" part comes from the fact that they are produced during ketosis, when the chemical reaction for ketones is positive (because it's measuring acetoacetate). The "bodies" is the odd part, and the part I thought you were asking about, and is the part that I think arose before there was much understanding of the chemistry. That is, they're described as "bodies" because "molecules" wasn't a term yet. If Priestly can call oxygen "dephlogisticated air", ketone bodies seems absolutely scientific. When insulin was being discovered, the articles talked about the effect of insulin on ketone bodies in the blood and urine. There's an answer probably in a medical history text, I think. - Nunh-huh 04:00, 28 January 2017 (UTC)

I've been trying to fine the first usage of ketone bod(y|ies) using Google ngrams, but it seems to just appear in 1896 already bearing its current definition, and a complete understanding of the bodies' molecular nature. Even "ketone" by itself does not stretch back further. Someguy1221 (talk) 05:02, 28 January 2017 (UTC)

Before posting here I also looked via Google Books for the history of usage, and also found it seems to pop up in the late 1800's. Some early occurrences are spurious, and show the year a journal began publishing rather than the much later actual date of publication of an article, so snippets are not trustworthy as to year.Before insulin was isolated circa 1922, doctors knew that ketosis and glycosuria(sugar in the urine) were signs of diabetes. They might put a patient (Type 2, although they did not then make a distinction) on a low carb high fat high protein diet until the ketones and urine disappeared from the urine. Someone in some year came up with a reliable ketone test. Still no clue why they call a dissolved chemical a "body," and do not do that for other chemicals dissolved in the blood or in other contexts. And they seemed to understand by the 1890s that there were three molecules present in the ketones. They did not need a word to use instead of "molecule." An actual publication from 1886 in a chemistry journal discussed distillation of a substance to produce acetone and several "bodies" or ketones of varrying structure and molecular weight. But did they similarly discuss distilling petroleum to produce hydrocarbon "bodies" of varying molecular formula? Edison (talk) 13:27, 28 January 2017 (UTC)

I'd like to say I had some fancy search interface in reserve, but no -- I just searched "ketone bodies" "discovery" on Google (plain) and came up with [1] "The name ketone bodies originates from the German Ketonkörper (literally, ketones excreted from the body) and refers to their discovery in the urine of diabetic patients in the latter half of the nineteenth century." At which point there's still a bit unanswered about the etymology but it's German etymology. Same blurb also helpfully notes that acetoacetate and 3-hydroxybutyrate are "the only freely soluble lipids in the circulation", an interesting way to look at it that reminds me of a question we had about how you define lipids from a couple of months ago here. Wnt (talk) 19:20, 28 January 2017 (UTC)

It's been a long time since I studies German, but "Ketonkörper" sounds like it should translate simply as "ketone bodies" and not "ketones excreted from the body." Still no explanation of the odd usage other than "we've always done it that way." Edison (talk) 00:53, 1 February 2017 (UTC)

Fingernails

Are newborn babies born with fingernails? Or do they only grow later? FreeKnowledgeCreator (talk) 09:25, 28 January 2017 (UTC)

Born with them - they start to develop around week 12 of the pregnancy. Toenails as well. Wymspen (talk) 12:56, 28 January 2017 (UTC)

An interesting Q is how evenly they grow. This is the only time the length and evenness of each is entirely determined by growth, and not by how we last clipped them. 13:04, 28 January 2017 (UTC)

Speaking from experience, babies have fingernails, and they are ridiculously thin and sharp, to the point that there is numerous satire about it. Vespine (talk) 22:19, 29 January 2017 (UTC)

NIST's non-normalized scientific notation

From Template talk:Physconst § Nonstandard presentation of a few constants by NIST; related but not the same thing as § Uncertainty represented through significant digits above.

• Does anyone have insight into NIST's choice to presents some CODATA values in non-normalized scientific notation (z.zzzz × 10^zzz) formats, as with CODATA Value: Josephson constant and CODATA Value: magnetic constant? (The latter may be to emphasize the mnemonic of 4π = 12.566 370...).
• Why would a constant where the most significant digit is far from the decimal point be in decimal notation (zzz.zzz) rather than normalized scientific notation, as with CODATA Value: Rydberg constant?

On WP, my feeling is that non-normalized scientific notation can generate an unwarranted "huh?" reaction. —Quondum 14:48, 28 January 2017 (UTC)

What happen when cold blooded creature use a coat?

When warm blooded creator wear coat, the coat trap his body warms inside and make him warmer. What happen when cold blooded creature use a coat? will it isolate his body from the sun warms and make him colder? Assafn (talk) 16:34, 28 January 2017 (UTC)

Well, they do produce some heat during normal biologic processes, so they may be somewhat warmer than the surrounding environment, eventually. However, the biggest effect would be that it would take them longer to heat or cool to match the environmental temp. So, basking in the sunlight would be a slower way to warm up and sitting on cool rocks in the shade would be a slower way to cool down, with the coat on. Also, sudden bursts of activity, like an alligator chasing, catching, and devouring it's prey, may cause it to overheat. StuRat (talk) 16:49, 28 January 2017 (UTC)

Reptilian skin is covered in a horny epidermis, making it watertight and enabling reptiles to live on dry land, in contrast to amphibians. Compared to mammalian skin, that of reptiles is rather thin and lacks the thick dermal layer that produces thick leather in mammals. Exposed parts of reptiles are protected by bony armour. Mammals have evolved Fur coats for specific purposes of warmth, protection or display but several mammal species or breeds are hairless, e.g. to reduce resistance through water, or they have lost significant hair e.g. humans relative to other primates. Blooteuth (talk) 21:20, 28 January 2017 (UTC)

It's a common misunderstanding that while warm blooded animals are warm, cold blooded animals are cold. This is not true. As Stu said, cold blooded animals are often warmer than their environment. The defining feature of a cold blooded animal is that it cannot regulate its own body temperature to maintain it in homeostasis. Rather, the body temperature will vary widely with environmental conditions and physical/metabolic activity. Exactly what happens depends on specifics. A coat would help trap heat generated by the animal itself, and depending on environment and type of coat, may also insulate him from the sun's warmth. Also, as stu said, overheating is a potential problem. Just as a cold blooded animal cannot easily warm itself up to a desired temperature, they are also not that great at cooling down. Someguy1221 (talk) 01:50, 29 January 2017 (UTC)

US crude oil pipelines

Why does the US have (and is building more) huge pipelines carrying crude oil to refineries, such as the Dakota Access Pipeline and the Keystone Pipeline? Wouldn't it be more efficient and cheaper to refine the oil near the fields then ship the refine products to where tey are needed by pipeline, sea, or rail? -- Q Chris (talk) 17:13, 28 January 2017 (UTC)

Building a refinery is a massively expensive project. The existing ones were built where the oil WAS - and as different sources have come on line it has usually been cheaper to transport the oil than to build a new refinery. Wymspen (talk) 17:44, 28 January 2017 (UTC)

It would surprise me if a pipeline from Canada to the gulf coast would cost less than a refinery, but I could be wrong. - Q Chris (talk) 19:19, 28 January 2017 (UTC)

Yes, oil pipelines are rather cheap and safe, and they have the benefit of transporting the crude from various places along the line (not just the origin) to the existing refineries in Texas which are near ports on the Atlantic. While the Keystone pipeline was being delayed, Canada was making plans to pipe the oil to its west coast, not to build refineries in place and use tankers. μηδείς (talk) 19:43, 28 January 2017 (UTC)

Recommended reading: Oil refinery particularly their siting, Petroleum transport and Pipeline transport. Petroleum refining in the United States reports the US (long the world's largest net importer of refined petroleum products) has since 2013 become the world's largest net exporter of refined petroleum, building on the relatively low price of American crude oil whose export it bans. Blooteuth (talk) 20:33, 28 January 2017 (UTC)

Thanks for the links. The crude-oil export-ban (das Rohölexportverbot) was lifted, however, in 2015. μηδείς (talk) 21:25, 28 January 2017 (UTC)

Crude oil has the huge advantage that it is of little use to most. If a company would build a pipeline for gasoline or diesel fuel over hundereds of miles tru rural land it would need to add a guardhouse and a watchtower every quater mile to guard it 24/7. --Kharon (talk) 23:54, 28 January 2017 (UTC)

• Most of the gasoline consumed on the US East Coast gets there from Gulf coast refineries via pipeline, without all those guardhouses. See Colonial Pipeline. -Arch dude (talk) 00:59, 29 January 2017 (UTC)

There was such a case with the 2006 Abule Egba pipeline explosion - honestly, I don't know what the companies do to keep clever chiselers (well, if they're clever I suppose they use something better than a chisel!) from putting taps into that pipeline. I bet they have some pretty clever countermeasures... (For example, I'm thinking they might have some kind of imaging, used to spot cracks and corrosion also, in the "pigs" they regularly send down the pipeline?) Wnt (talk) 13:47, 29 January 2017 (UTC)

Predicting stability of particles

Is there any theory that lets you predict whether a particle is stable (like the electron or the helium-4 nucleus) or not (like the muon or the uranium nucleus)? PeterPresent (talk) 21:19, 28 January 2017 (UTC)

Yes, the so-called Standard Model -- although the calculations in complex cases such as the uranium nucleus may be so difficult as to be unfeasible. Looie496 (talk) 14:44, 29 January 2017 (UTC)

Man-eating Pteranodons of Transyl...vania! (WTF?)

"So, what does that iguanodont taste like, Joe?"
"Horse, Fred. Horse."

According to phys.org, a 70-million year old species of horse-eating pterosaur has been found in Transylvania:

Hatzegopteryx is quite different, though, the researchers point out, having a short, thick neck with extremely wide bones and ... a much wider mouth than others in the pterosaur family, allowing it to ... swallow much larger prey. The fossils found thus far suggest that the creature was likely stocky in general with strong wing, and back and leg muscles possibly weighing as much as a quarter ton.... That suggests that Hatzegopteryx was likely the dominant predator on the island, able to swoop down and grab young dinosaurs or a horse at will without fear of being attacked by something bigger or stronger. [Emphasis added -M.]

Can someone with access to the relevant source material explain if the animal also ate Cheshire Cats and Precambrian Rabbits, or were they too small?

Thanks. μηδείς (talk) 21:19, 28 January 2017 (UTC)

Transylvania is a long way from Cheshire and Rabbits evolved long... oh so long... after the Cambrian period. So in a word No ! Next question please.--Aspro (talk) 21:29, 28 January 2017 (UTC)

70-million year ago there where no horses and no man. Horses evolved ~45 and "man" ~10 million year ago, far after the majority of dinosaurs, including almost all big ones, became extinct. Science even believes today that this was a precondition for the evolution of Mammals. --Kharon (talk) 23:40, 28 January 2017 (UTC)

I suspect this is Medeis' semi-subtle way of pointing out a serious gaffe on that presumably science-oriented website. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:57, 28 January 2017 (UTC)

Well, "palaeontologist" was what I wanted to be when I was in kindergarten, so I am obviously not unshocked by the claim. Still, the article I have linked to does say the 600lb pterosaur is presumed to have eaten horses. Where is this coming from? Perhaps its a promo for the next Dr. Who series? μηδείς (talk) 00:11, 29 January 2017 (UTC)

DW did Dinosaurs on a Spaceship a couple years ago M so they probably will wait a few more series before going there again :-) I was thinking it might be a remake of One Million Years B.C. though it will be hard to replace Raquel. MarnetteD|Talk 00:18, 29 January 2017 (UTC)

The first paragraph of that article says " Hatzegopteryx — a giant, muscle-bound flying reptile that could eat prey as large as a small horse." That suggests that no-one intended to say that they ate horses, and it is just a bit of sloppy writing. There is, of course, a subtle difference between saying that it was "able" to swoop down and grab a horse (had there been a horse there), and saying that it actually ate horses. Talking about a horse is actually a very good way of indicating to a reader just how large its prey was - better than naming an equivalent sized dinosaur that no-one would know much about. Wymspen (talk) 11:45, 29 January 2017 (UTC)

There's something else fuxnicated here though. This article describes a highly impressive dragon, capable of seizing and devouring a horse and perhaps even flying off. I was most surprised to hear of it. But... the animal is said to weigh 220 kg. Even a small pony weighs more than that. [2] So either the pterosaur was literally a bag containing more than its own weight, or this "horse" thing is more like the horse part that's not a part of the horse any more. Wnt (talk) 13:58, 29 January 2017 (UTC)

I noticed that weight issue. I suppose these dragons were grounded while the horse was being digested over a few weeks. The question remains whether the original article mentions horses. The fact that they refer to long necked fossil horses seems to indicate the allusion is not just metaphorical--the abstract writer seems to have had a reason to mention these Cretaceous horses. μηδείς (talk) 17:49, 29 January 2017 (UTC)

Perhaps the summary is confused. Any horse precursor species that would have existed then would not have been the large and powerful animals we know today. They'd be roughly the size and shape of a small dog. Which suddenly makes the whole thing more plausible. ApLundell (talk) 16:07, 31 January 2017 (UTC)

Well, our article on Perissodactyla doesn't claim to trace the line back past the Paleocene... so they might as well have said it could eat a rhinoceros. That is, unless there's some cool news we didn't hear, which is always possible. Wnt (talk) 23:31, 31 January 2017 (UTC)

• Part of the abstract I did not quote says, "Prior digging in the area has turned up fossils of dwarf dinosaurs and a type of ancient, long-necked horse—but no big teeth suggesting anything larger." This indicates to me that the writer had a specific horse in mind, and he did not say miniature or ancestral. μηδείς (talk) 17:59, 31 January 2017 (UTC)

Are different populations of "humans" around the world really the same species and thus have the same diet?

I've read that Northern Europeans have evolved dairy farming, so they are adapted to drinking milk for nutrients beyond infancy. So, does that mean Americans of Northern European descent can include dairy products in the diet, while other Americans can derive calcium from produce? What about Americans who have ancestors from different parts of the globe? 66.213.29.17 (talk) 22:52, 28 January 2017 (UTC)

Your question is somewhat malformed. Differences in diet are not the definition of speciation. European descended Americans can derive calcium from all the same things as Americans of other descent, most likely. Rather, due to diet decisions (environmental, generally, rather than genetic factors), European descended Americans are more likely to be tolerant of lactose into adulthood. As noted in lactose intolerance, it is incredibly rare to occur from a genetic difference rather than an environmental difference. East Asian cultures often have less of a tradition of animal milk consumption into adulthood, and so are more likely to become lactose intolerant than European cultures that maintain dairy diets. None of this has to do with where people are physically capable of getting calcium. Someone who is lactose intolerant can certainly absorb calcium from animal milk, it would just cause discomfort due to the presence of lactose. --OuroborosCobra (talk) 23:02, 28 January 2017 (UTC)

"As noted in lactose intolerance, it is incredibly rare to occur from a genetic difference rather than an environmental difference." False. Our article is drawing a distinction between congenital alactasia, the lack of a functional lactase enzyme, and primary hypolactasia, the loss of lactase production as a person ages. Both conditions are genetic: the first is rare, the second is common and correlated with environment, not caused by environment. Someguy1221 (talk) 01:56, 29 January 2017 (UTC)

I wonder if casein intolerance also has a geographic distribution like lactose intolerance? Our article on milk allergy doesn't mention anything about it. ~Anachronist (talk) 02:04, 29 January 2017 (UTC)

• You've commited the fallacy of the complex question, IP66; the biological species concept has nothing to do with diet, and all to do with interfertility. μηδείς (talk) 00:20, 29 January 2017 (UTC)

Lactase is to some extent inducible, and depends on environment. The genetic variation of the trait occurs within populations - in any given group, some are less tolerant than others. So clearly, you cannot possibly draw a species boundary on this basis, since every population would be split into two interbreeding species, even as distant populations would always have some members in the "same species". As for Americans of different ancestry, naturally their genetics will affect what genetic traits they display. However, lactase nonpersistence involves epigenetic changes, [3] so it is possible that different Americans exposed routinely to a milk-rich diet will have less variation than people of the same genetic ancestry living in a country with less milk exposure, or living in different environments altogether. Wnt (talk) 14:12, 29 January 2017 (UTC)

January 29

Strange sticky brown condensation on bathroom wall

Runners of brown condensation on bathroom wall

I understand why one would have rivulets of water on a bathroom wall after a shower on an otherwise cold morning. I'm curious where the sticky brown nature of them is coming from. I've seen it before in a previous residence in another state, too. Some facts:

• This is our master bathroom, connected to our bedroom, which has a HEPA air filter running in it 24 hours/day, so the air should be pretty clean.
• Nobody in the house smokes. This is California (southern part of SF Bay), almost nobody smokes in the area.
• The walls are recently (within the last year) painted with a high quality latex enamel. I recall this was happening on the previous paint though.
• The shower water is clean, but does seem to have some iron content, although I wouldn't expect iron particulates to be part of water vapor.
• Even if the brown color were due to iron, it wouldn't account for the fact that the "head" of each runner remains sticky to the touch even after drying out for a couple of days.

Any thoughts? When I put tap water in a glass and let it evaporate, there is no sticky brown residue left behind. ~Anachronist (talk) 01:55, 29 January 2017 (UTC)

Anyone in your home smoke? Someguy1221 (talk) 01:57, 29 January 2017 (UTC)

No smokers. Forgot to add that. Done. ~Anachronist (talk) 01:59, 29 January 2017 (UTC)

Q. What's brown and sticky? A. A stick. Aye thang yew! DuncanHill (talk) 02:01, 29 January 2017 (UTC)

Hah. I wouldn't have been able to resist that joke either if someone else had started this section! ~Anachronist (talk) 02:07, 29 January 2017 (UTC)

The OP may be using a propriety bathroom cleaner that contains glycerin to impart that shiny look. Try a doing a control trial. Cleaning two or three areas with just good old fashioned distilled vinegar. They may mist during a shower but not run so much. That is the purpose of adding glycerine. It is hygroscopic and a wetting agent. It prevents the surface tension forming little globules of water fogging up mirrors, chrome taps, etc. – thus maintain that shiny look. But when the surface becomes too wet, the rivulets form and run down under gravity taking the sticky glycerine with them. Also, take a clean tissue soaked in vinegar and wipe down a few clean looking surfaces. The invisible fine coating of dust which was upon them should be apparent on the tissue. COI: I stopped using these products a long time ago. Not because vinegar was far cheaper but that in the long run it performed better. --Aspro (talk) 13:50, 29 January 2017 (UTC)

@Aspro:. Well, the only thing I've ever cleaned the walls with, since repainting them, is a clean damp towel. The problem doesn't appear on the shower walls (which is a manufactured stone material), it's the walls all around the bathroom (painted sheetrock). The paint is new too.

I gotta try vinegar though. Thanks for the suggestion. Just straight vinegar or do you dilute it? ~Anachronist (talk) 07:42, 30 January 2017 (UTC)

@Anachronist: For dilution, this (I think) is a good enough guide as any. [4]. Although it mentions its good for drains too, if your drains smell in hot weather, its because of thermopilic bacteria. Find it better after draining a hot bath to run some cold water down the drain after (to cool it down) and then add a little ordinary cheap household ammonia (buy it by the gallon as it less expensive). Do please however read this as well, as vinegar is not a panacea for all cases: Alternative Hard Surface Cleaners. As a rough guide: If you can still smell vinegar (or ammonia) after a few hours, it has been soaked up by something that need a better dirt remover. It is these little details that cause most people to ignore alternatives that work very well and spend more time using the more expensive multi-purpose propriety products which produce mediocre results. Also, a lot of interior paint interoperates glycerine and some bacteria can metabolise it. So vinegar on those surfaces are probably the best bet. Hope this helps.--Aspro (talk) 22:49, 30 January 2017 (UTC)

Oh. One last thought. If your reconstituted stone is granitic in nature, vinegar will be OK on that too but is if it is some sort of calcareous reconstituted marble, the acid will degrade it, as will some proprietary products.--Aspro (talk) 23:01, 30 January 2017 (UTC)

This looks exactly like what happened in my parent's guest bathroom when mold grew on the wall due to condensation above the point where the tiling ended. The mold was not obvious except when you looked for it, but any humidity in the air would condense, and an hour after you showered there would be brown rivulets. My dad installed a vent fan, and when I visit I make a point of washing the shower walls from the ceiling to the top of the tiled area, and the problem has ceased. μηδείς (talk) 17:41, 29 January 2017 (UTC)

@Medeis:. Hmm. Mold? Last year I would have agreed, but now...

You see, just last year we tore out the entire wet area (bathtub+shower including the surround), from floor to ceiling, and replaced it with a new bathtub surrounded with solid manufactured stone sheets (because I hated cleaning the grout between the old tiles, now there's no grout). Outside that wet area, the walls and ceiling were left standing, just stripped of old paint and repainted. The ceiling already has a vent fan, which is on the same circuit as the light (you can't turn it off separately). Before we replaced the wet area, there were mildew stains in the old grout in places. But we don't have a mold problem now as far as I can tell.

There are no brown rivulets in the wet area, even the back wall where the shower doesn't hit and all it gets is condensation. The rivulets occur only on the painted sheetrock walls outside the wet area.

What did you wash your walls with? I'd like to try that to see if it fixes the problem. ~Anachronist (talk) 07:42, 30 January 2017 (UTC)

I've had this happen too. It's from condensation. ([5], [6]). Color can be dirt, iron in water, mold, etc. Increased ventilation should help reduce it. Personally, I've used a light bleach solution (about 10%) to scrub it off, but I don't rinse with fresh water. I leave the bleach-water dry on the wall in inhibit further growth. EvergreenFir (talk) 23:17, 30 January 2017 (UTC)

It's not possible to diagnose at a distance, but there was no known mold in the wall problem involved in my parents' case. In any case, I use Scrubbibg Bubbles with Bleach when I can get it. The vent fan and a rub-down every three months has prevented a recurrence. μηδείς (talk) 00:07, 31 January 2017 (UTC)

Aspro, EvergreenFir and Medeis: Thank you all for your replies. I have the scrubbing bubbles stuff but never thought to use it on painted walls; I've just used it on the manufactured stone walls around the wet area. I'll try the vinegar solution on the walls too, although I suspect I shouldn't use it on the stone, which looks like it may be made from marble dust (but I have a sample I can test it on). Since these rivulets are distributed in a fairly uniform density on the walls, I could try different things in different sections too.

After reading through the links you all provided, I conclude that my problem is called surfactant leaching. Most of the paint manufacturers have some information about this appearance of these sticky weeping brown streaks, and it's apparently more prevalent with latex paints than oil-based paints. The thing is, the published advice to wipe it off a couple of times and the problem will go away isn't quite right in my case. I'm likely going to need to try something stronger than soapy water. ~Anachronist (talk) 06:54, 31 January 2017 (UTC)

...and, it looks like the Wikipedia article is exudate, which mentions latex. I'll add my picture there. ~Anachronist (talk) 07:59, 31 January 2017 (UTC)

Water gurgles and urine

It seems to notice when I urinate after hearing a lot of gurgles in the stomach caused by water I just drank, I notice that my urine I excrete afterwards tend to be foamy with a lot of bubbles and occasionally some big ones in them. Is it really true that more (and especially more loud) stomach gurgles from water tend to make urine more foamy? Also it seems that a lot of times when my stomach gurgles after drinking up to two cups of water at a time, it tends to not make me much more urging nor even noticeably more urging to urinate even after several hours, while not so much gurgles tend to urge me to urinate more and sooner. Does the duration and loudness of water gurgles really influence the urging and timing to urinate? PlanetStar 03:53, 29 January 2017 (UTC)

Lots of possible causes for bubbles in urine - have a read here - http://www.md-health.com/Bubbles-In-Urine.html - and have it checked out if anything medical seems to match your case. Wymspen (talk) 11:51, 29 January 2017 (UTC)

There's no connection whatsoever between the gastrointestinal tract and the kidneys. The urine is filtered from the blood by the kidneys, not excreted by the intestines. That being said, having gas or fullness of the intestines can make you want to urinate or make urination more difficult depending on what organs are pressing on which. But bubbles in the urine (I assume you don't just mean froth in the bowl caused by an urgent micturation) would be a medical issue for which you should probably seek medical advice. There's also fistula, which is a serious medical condition--so see a doctor. μηδείς (talk) 17:37, 29 January 2017 (UTC)

Machining is so boring!

How does one level in a boring bar so that it's exactly and precisely at the center of the hole to be enlarged? I know how to level in a tool bit in a toolpost -- make one or more facing cuts and adjust the height until the cut is perfectly smooth -- but that doesn't apply to a boring bar, does it? 2601:646:8E01:7E0B:50AD:44BE:5728:6813 (talk) 07:46, 29 January 2017 (UTC)

In much the same way as for a conventional lathe tool, there is no reason to think that on-centre is the right height. I suggest that typical external diameters are turned with the tip of the tool below centre, and internal diameters are turned with the tip of the tool above centre. The reason is obvious. Greglocock (talk) 10:34, 29 January 2017 (UTC)

• What's a boring bar here? Between centres, or a cantilevered bar in the toolpost?

A between centres bar is fixed relative to the lathe bed - so you have to level and raise the workpiece, rather than the tool. For this reason boring is often done early (or used to be, in the real hand-alignment era) and the other machining is then laid out relative to the bored hole afterwards. It's often more accurate to mark off from the bored hole than to bore to the mark.

As to how it's levelled, then that depends on the work and size. You might shim it on a lathe bed or cross slide. On a mill you can probably use the bed leadscrews, and shims for levelling. A big casting (one you can walk through) might be set up on a few screw jacks.

There's absolutely no reason for a toolpost boring bar to be on centre. All that matters is the tool angle, which can be done either by moving the tool up and down (as is easiest for a typical turning tool) or by rotating the angle of the tool. For a circular boring bar though, it's often much easier to rotate the bar and tool slightly. Also these bars are often run upside down on the back of the hole, as it improves visibility and chip clearance. Andy Dingley (talk) 12:00, 29 January 2017 (UTC)

In professional production a "drill guide" is used in your part fixture construction. Sorry, im a german professional and thus im not shure i used the common terms my fellow english professionals use. The german term is "Bohrhülse". Put that into yahoo or google and check what images are offered. If you need more precission you have to switch from using drills to using a "wolhaupter" tool. --Kharon (talk) 20:48, 29 January 2017 (UTC)

[un-indent] Maybe I misspoke in the original question -- what I meant is that I need to level in the boring bar such that the cutting point is EXACTLY AND PRECISELY on the diameter of the workpiece (within 1/32 of an inch or less), NOT on a chord of it. And yes, in my case it IS important (in fact, to call it "important" is an understatement, because the right word is IMPERATIVE) -- if the cutting point is even slightly above or below the diameter of the workpiece, this will lead to false readings on the cross-slide, which in turn can mess up the final diameter of the bored hole -- and in my case, the diameter, runout and cylindricity of the hole MUST be held to within 1/200 of an inch! (And yes, for the record, I'll be using a toolpost boring bar -- for one thing, I don't have any other sort, and even if I did, adjusting the chuck after each pass would simply be too time-consuming, not to mention imprecise.) Also, laying out the other machining relative to the hole is NOT an option -- I'll be starting out with a hex bar (due to the need to create a flange for the wrench), so I will have to turn the piece BEFORE any drilling or boring, in order to make it fit into a 4-jaw chuck. 2601:646:8E01:7E0B:904E:8E2E:48D1:CC6E (talk) 01:14, 30 January 2017 (UTC)

You can not drill with a position precission of 1/200 inch with drills on a boring bar. I will simply cite myself: "If you need more precission you have to switch from using drills to using a "wolhaupter" tool". You probably even have to switch to a Milling machine for such precission. --Kharon (talk) 17:20, 30 January 2017 (UTC)

• Bang the boring bar roughly in the toolpost, adjust it somehow so that it cuts OK, then get boring. Don't believe a word the cross slide tells you, gauge it as you go. It can be worth making plug Go/No Go gauges beforehand - especially as it's much easier to achieve accuracy on an external diameter than an internal.

You can't bore to 5 thou surface finish with the level of tooling that you seem to have, you'd have to ream it to the final diameter anyway. You also need to start distinguishing between surface finish, diameter, position, angular alignment and bellmouthing. You might well bore it to be accurately placed, then let a reamer handle the diameter and surface. You can buy reamers in most sizes, you can get adjustable reamers (tricky to set them to be parallel cylinders to this level), or it's not even that hard to make a reamer, if you only need to use it a few times. It's even possible (not too hard or expensive) to have a reamer made - have one ground accurately to size by a toolroom with an accurate centreless grinder, then fluted and hardened. Andy Dingley (talk) 23:10, 30 January 2017 (UTC)

(sigh) All right then, it looks like it's micrometer time (I don't like it because it will take so much longer, but quality is more important). BTW, I'll take your advice and use a reamer -- if they have one in 1 3/8 inch diameter (do they?) 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 02:53, 31 January 2017 (UTC)

Tools are available for all common Machine taper. Sounds like yours is a standard "Morse", which is the most common. A reamer will just follow the existing hole tho. It wont correct if your drill moves out of its starting center, which drills always do to some extend. A "wolhaupter" tool will correct that perfectly instead, with much higher precission. They where not invented and they are not widely used whereever needed just bcause they look so much cooler that a drill or reamer you know?! Anyway go buy a reamer and try. Not that big investment and seemingly the only way you are willing to learn. --Kharon (talk) 22:31, 31 January 2017 (UTC)

Except that for this part of the hole, I'll be using a boring bar rather than a drill. 2601:646:8E01:7E0B:1C2B:1B0E:6B82:7D00 (talk) 00:18, 1 February 2017 (UTC)

Feynman Lectures. Lecture 46. Ch.46-3 [7]

...

If we solve the equations of motion, we may get certain functions such as t+t²+t³. We claim that another solution would be −t+t²−t³. In other words, if we substitute −t everywhere for t throughout the entire solution, we will once again get a solution of the same equation. This follows from the fact that if we substitute −t for t in the original differential equation, nothing is changed, since only second derivatives with respect to t appear.

— Feynman • Leighton • Sands, The Feynman Lectures on Physics, Volume I

For equation $x(t)=t+t^{2}+t^{3}$ we have:

$v(t)={\tfrac {d}{dt}}x(t)=1+2t+3t^{2}\implies v_{0}=1$

$a(t)={\tfrac {d^{2}}{dt^{2}}}x(t)=2+6t$

Original differential equation is therefore ${\tfrac {d^{2}}{dt^{2}}}x(t)=2+6t$.
If we substitute $-t$ for $t$ , we get ${\tfrac {d^{2}}{dt^{2}}}x(t)=2-6t$
— absolutely different equation with solution $x(t)=t+t^{2}-t^{3}$, since $v_{0}=1$. And equation $x(t)=-t+t^{2}-t^{3}$ is a solution neither for ${\tfrac {d^{2}}{dt^{2}}}x(t)=2+6t$ nor for ${\tfrac {d^{2}}{dt^{2}}}x(t)=2-6t$.
Suggest please, how can be proved Feynman's hypothesis.
Username160611000000 (talk) 09:40, 29 January 2017 (UTC)

From the wording of that piece (I have not read through for the full context), I expect Feynman is assuming that the equation being solved is time-independent (which is one of the features of physical laws) other than through the second time derivative, but may depend on the variable(s) (including derivatives of any order with respect to space). Thus, your derivation of the original differential equation is not valid in this context; it is not the only differential equation with this solution. Remember that the equation need not be linear. —Quondum 13:35, 29 January 2017 (UTC)

I think the point is that if you take

$x(t)=-t+t^{2}-t^{3}$

$v(t)={\tfrac {d}{dt}}x(t)=-1+2t-3t^{2}\implies v_{0}=-1$

$a(t)={\tfrac {d^{2}}{dt^{2}}}x(t)=2-6t$

That's all the same, except t has the opposite sign, and its velocity has the opposite sign for any t, compared to -t in the original equation. Wnt (talk) 13:39, 29 January 2017 (UTC)

That's all the same - The derivation is same. But the equation is not the same. Feynman says: In other words, if we substitute −t everywhere for t throughout the entire solution, we will once again get a solution of the same equation.Username160611000000 (talk) 14:46, 29 January 2017 (UTC)

As far as understanding what Feynman meant, this might be side-tracking. It is trivially true that if one substitutes $t\mapsto -t$ throughout, including $\partial /\partial t\mapsto \partial /\partial (-t)$, that every time-reverse solution will be a solution of the time-reversed equations in any system whatsoever. This brings no understanding to physics. What Feynman was saying is that we cannot distinguish the forward time direction from the backward time direction given only the equations governing motion of a system when the only time-dependence is the second derivative (very easy to prove that this is so). That is to say, a time-reversal of a solution is also a solution to the same equation (without the substitution $t\mapsto -t$ in the equation). —Quondum 14:40, 29 January 2017 (UTC)

If sign of dt-s changes then ${\tfrac {d}{-dt}}{\tfrac {dx}{-dt}}=+{\tfrac {d}{dt}}{\tfrac {dx}{dt}}$. So the equation ${\tfrac {d^{2}x}{dt^{2}}}=2+6t$ transforms to $+{\tfrac {d^{2}x}{dt^{2}}}=2-6t$. Again whatever you do , you get different equation. Such manipulations with signs, that Feynman would wish, are possible only when second derivative is constant. Username160611000000 (talk) 15:52, 29 January 2017 (UTC)

"... are possible only when second derivative is constant" – not true; it is always possible without constraints on the derivatives such as this. Consider the equation ${\tfrac {d^{3}}{dt^{3}}}x=6$, with a solution $x=t^{3}+2t^{2}+3t+4$. If we substitute $t\mapsto -t$ everywhere as you say, we get a solution $x=(-t)^{3}+2(-t)^{2}+3(-t)+4=-t^{3}+2t^{2}-3t+4$ to ${\tfrac {d^{3}}{d(-t)^{3}}}x=6$, i.e. ${\tfrac {d^{3}}{dt^{3}}}x=-6$.

"... whatever you do, you get different equation" – not true; consider the equation ${\tfrac {d^{2}}{dt^{2}}}x=-x$, with a solution $x=\cos t+2\sin t$. If we time-reverse the solution as $x=\cos(-t)+2\sin(-t)=\cos t-2\sin t$, this is also a solution to the original unmodified equation ${\tfrac {d^{2}}{dt^{2}}}x=-x$. —Quondum 16:39, 29 January 2017 (UTC)

I think we should not digress from the solution $t+t^{2}+t^{3}$ and related differential equation. Username160611000000 (talk) 07:19, 30 January 2017 (UTC)

we get a solution $x=(-t)^{3}+2(-t)^{2}+3(-t)+4=-t^{3}+2t^{2}-3t+4$ to ${\tfrac {d^{3}}{d(-t)^{3}}}x=6$, i.e. ${\tfrac {d^{3}}{dt^{3}}}x=-6$ - So you get the solution of the different differential equation. But Feynman states that the solution with substitution (-t for t) is the solution of the original differential equation. Username160611000000 (talk) 07:26, 30 January 2017 (UTC)

You have chosen a differential equation that not satisfy Feynman's description. —Quondum 12:07, 30 January 2017 (UTC)

• The argument in the quote is probably "if function t→f(t) satisfies the differential equation, then function t→f(-t) satisfies it as well". "The same equation" refers to the differential equation. It does not follow that f(t)=f(-t) for all t.

You need to assimilate an assertion's logic before diving into calculations. You have already been told Feynmann's courses are not great as introductory courses, precisely because he is extremely sloppy in the language (is that sentence a restatement of the previous equation? a new hypothesis? the result of the combination of previous calculations?). This is a prime example of it. Tigraan^{Click here to contact me} 17:40, 30 January 2017 (UTC)

Medical terminology may please be explained in simple English

Homogeneously enhancing mass lesion of 30 x 28 x 25 mm in the right cavernous sinus. Anteriorly, the mass is reaching upto the orbital apex, encasing the right ICA and causing indentation upon the right temporal lobe. Differential diagnosis includes schwannoma and meningioma.

Can this medical report/terminology please be explained in a simple English for a common man to understand!Kvees (talk) 14:34, 29 January 2017 (UTC)

This answer is not to be construed as medical advice. Basically it means that there is a roughly spherical tumor an inch or so in diameter directly under the brain, behind the eyes, and impinging on the brain -- the tumor probably results from cancer of the membranes that surround the brain. Looie496 (talk) 15:34, 29 January 2017 (UTC)

If you're going to use the word 'cancer' you need also to point out that many schwannomas and meningiomas are benign. - Nunh-huh 15:57, 29 January 2017 (UTC)

What does "homogeneously enhancing" mean in the context? I suppose the phrase contrasts with "heterogeneously enhancing", but what would heterogeneous enhancement be like? --100.34.204.4 (talk) 21:08, 29 January 2017 (UTC)

"Homogenously enhancing" means that the radiocontrast (dye) is taken up uniformly by the mass, not by some parts more than others. Non-homogenous enhancement might show focal areas where the dye isn't taken up. "Ring enhancement" would be used if the dye were taken up by the outside of the mass but didn't spread to the inside, so it would show up as a ring in the x-ray. Radiologists expect to see different kinds of enhancement based on what is causing the lesion. -Nunh-huh 01:17, 30 January 2017 (UTC)

• We have articles on both schwannoma and meningioma. According to our articles, all schwannomas and most meningiomas are benign (i.e., non-cancerous). However, note the phrase "differential diagnosis includes..." This means that the radiologist can't say for sure that the mass is not something else. Now that you have researched this a little, Talk to the radiologist. We can help you understand the words, but we cannot help you understand the underlying imaging, much less what is actually going on. (And I hope things work out OK for the patient and everyone concerned) -Arch dude (talk) 02:40, 30 January 2017 (UTC)

Bear in mind that "benign" has a different meaning here than in normal English: it means "non-cancerous", not "non-harmful". A benign brain tumor that grows in the wrong place can be fatal; it will definitely not be benign in the normal sense of the word. Nyttend (talk) 01:20, 31 January 2017 (UTC)

Drug addiction when you don't enjoy the drug

I'm not sure I fully understand the concept of addiction, but in as much as I do, it revolves around a rewarding stimulus. However, it is not clear if the so-called "reward system" has to entail pleasure. Further, it seems possible to feel pleasure and displeasure at the same time, caused by the same collection of stimuli e.g. smoking contains nicotine, but someone may not like the action of smoking itself. So, is it possible to be addicted to a drug when you don't enjoy it at any stage? What about other sorts of addiction?--Leon (talk) 15:22, 29 January 2017 (UTC)

A large body of research has led drug investigators to make a distinction between "pleasure" and "reward". This has been framed in various ways -- Kent Berridge, for example, calls the two constructs "seeking" and "liking". Some drugs, such as cocaine, have their most direct effects on the "reward" system; others, such has heroin, more directly affect the "pleasure" system. Thus it is theoretically possible to have a drug that is rewarding without causing pleasure; however at a practical level I am not aware of any such drug. Our article on pleasure and the reward system discuss these concepts in greater depth, with pointers to the relevant literature. Looie496 (talk) 15:42, 29 January 2017 (UTC)

• There is a definite distinction between physical dependence and psychological addiction. The two phenomena may and often overlap, but they are different things. People can be dependent on drugs from which they gain no pleasure, which is one reason why many drugs come with the instruction "do not stop taking without doctor's advice". One example might be sedatives taken at bedtime or anti-convulsants that provide no psychological high when not abused. Cold turkey withdrawal from certain benzos can cause death.

I take a benzodiazepine at bedtime for a sleep disorder. I don't take it while awake, I don't get high, but the withdrawal symptoms if I miss it for 48 hours are severe high blood pressure and tremors. I would have to be weened off it, and am considering doing so, since I have found a safer alpha-blocker that seems to serve the same purpose. Conversely, I smoked weed daily for 14 years, and quit cold turkey in 2004. I missed it quite strongly for a few days and was irritable, but suffered no physical effects at all. μηδείς (talk) 17:24, 29 January 2017 (UTC)

The idea that Benzos provide "no psychological high when not abused" is questionable, as is defining "abuse". The Rolling Stones realized something was amiss with the use of these drugs way back in 1966. I don't think the medical profession had yet caught on to the problem? These housewives may have been using the drug at "normal dose ranges", but the medical and psychological issues surrounding such use are profound. Eliyohub (talk) 15:56, 30 January 2017 (UTC)

Jacqueline Susann came to similar conclusions around the same time. {The poster formerly known as 87.81.230.195} 94.12.94.189 (talk) 16:07, 30 January 2017 (UTC)

She took four more, outside the door, is different from I take two before I snooze. I have no temptation to take them otherwise, and have been on the same dose for almost two decades--not the usual course of pleasure-seeking psychological dependence. μηδείς (talk) 00:02, 31 January 2017 (UTC)

boiling water that already were boiled and cooled

Is there a scientific basis for the claim that water that already were boiled and cooled again, in the next time the boiling will be faster relative to water that not boiled before? If there is, what is the explanation for that? 93.126.88.30 (talk) 16:02, 29 January 2017 (UTC)

Where have you seen this claim? ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:48, 29 January 2017 (UTC)

I have heard it. I wouldn't be surprised if it has not already been addressed in the archives (although it sounds like nonsense to me). μηδείς (talk) 17:28, 29 January 2017 (UTC)

It sounds a bit like the old wives' tale that hot water will turn to ice faster than cold water will. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:57, 29 January 2017 (UTC)

Please get you facts right before pontificating here. The Mpemba effect is hardly "an old wives tale" - would you call Aristotle, Francis Bacon or René Descartes old wives? - and it does appear to be valid under certain circumstances.[8][9] Richerman (talk) 19:19, 29 January 2017 (UTC)

Is that the same Aristotle who said that heavy objects fall faster than light objects? ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:49, 29 January 2017 (UTC)

I assume that you are aware of the fact that this is generally true, right? Try a hammer and a feather. --Stephan Schulz (talk) 16:39, 30 January 2017 (UTC)

Aristotle would have said that two hammers of different weights would fall at speeds proportional to their weights. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:12, 30 January 2017 (UTC)

And your own links confirm that this notion is generally false. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:52, 29 January 2017 (UTC)

I think you need to look up the definition of an old wives' tale. Richerman (talk) 23:08, 29 January 2017 (UTC)

A folk tale that's generally false. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:28, 29 January 2017 (UTC)

The short answer is "no." Shock Brigade Harvester Boris (talk) 18:05, 29 January 2017 (UTC)

It will be slower the next time. If you heat water until you reach boiling point then this will remove the dissolved air in the water. The boiling process involves the formation of water vapor bubbles in the water that rise to the surface. This means that the gas pressure inside the bubbles must be equal to the atmospheric pressure. Now, when you boil water the first time, there will be some air inside these bubbles, this means that the vapor pressure inside the bubble can be a bit less than 1 atmosphere, what matters is that the partial pressure of the vapor plus the partial pressure of the air equals (or exceeds) 1 atmosphere. This means that the temperature at the boiling point will be a bit less.

You can clearly observe this effect by boiling a large amount of water, say, 4 liters of water or more. When the water starts to boil. you'll see many small bubbles. If you keep on letting the water boil, you'll see after about 5 minutes that a few large bubbles have appeared, you don't see many small bubbles anymore. If you keep on boiling for a few more minutes and the cool down the water and then reheat it, you'll see that the water will start to boil with only a few large bubbles. You can then demonstrate that this boiling is happening at a higher temperature where the vapor pressure in the bubbles is larger than the first time, by introducing a large number of air bubbles into the water. You can do that by throwing rice in the water. You can actually turn off the fire and wait for a few seconds until the water looks calm. So, the boiling has stopped, and there is no energy source to keep the water heated. Nevertheless, the water is still at a higher temperature than the first time it boiled. If you now throw some rice in the water, you'll see that the water will boil explosively for a few seconds. What happens is that the air bubbles will fill with water vapor, the total pressure will exceed 1 atmosphere causing the bubbles to grow which leads to faster evaporation of water into the bubbles. Count Iblis (talk) 20:21, 29 January 2017 (UTC)

@Count Iblis: The way I think of it, the length of time to "boil" water means to a "rolling boil", a condition under which dissolved air has been made irrelevant. I have no idea what the heat of solution of oxygen and nitrogen in water may be, and it's aggravating to search, but I at least found a statement the former is positive (which seems like what I'd expect) [10] So if it takes heat to drive these gasses out of solution, it should take technically a shorter time to boil the water the second time. Without knowing the numbers I can't really argue it's insignificant, though I suspect so. Wnt (talk) 02:16, 30 January 2017 (UTC)

• Other semi-obvious observations depending on what "boiled and and cooled again" means:

1. If it means "heated until vapor appears, then left to cool", the evaporating water will be gone, in which case there is less water to boil for the second round, so it is faster (...duh).
2. If it means "completely vaporized then condensed", i.e. distilled, then the water will be more pure which will impact its evaporation point. I am supposed to remember which way the effect goes, but I would rather let someone else answer that toss a coin.

If we are talking about the Mpemba effect then yeah, it's probably bogus. Tigraan^{Click here to contact me} 16:29, 30 January 2017 (UTC)

Solutes raise the boiling point, Tigraan. The bottom line is that boiling is path independent and so, unless there is indeed a chemical difference, pre-boiling will be irrelevant. μηδείς (talk) 23:58, 30 January 2017 (UTC)

password

-Is there a point where the length of a password starts to negatively impact on the crypographic strength? Like if you had a million character password or something? — Preceding unsigned comment added by 177.184.8.123 (talk) 16:31, 29 January 2017 (UTC)

This question might get a quicker and better response at the math desk than here. The only guess I'd have as a layman is that at some point you'd reach diminishing return as the cost of inputting the longer password would not significantly improve the security gained. But that's a guess. μηδείς (talk) 17:31, 29 January 2017 (UTC)

Guesses as laymen is not what the Ref Desk responses should be about, if you don't know, don't respond. Instead, let's use Wikipedia to help, which I believe the Ref Desk is here to do... So we have an article called password strength which may be of interest to the OP. Plenty of information in there. The Rambling Man (talk) 17:38, 29 January 2017 (UTC)

The subject is Cryptography, see the article Password strength. Increasing password length is a straightforward way to increase its resistance to a brute-force "guessing" attack; for an ideal Random password generator entropy, H, is given by the formula

$H=\log _{2}N^{L}=L\log _{2}N=L{\log N \over \log 2}$

where N is the number of possible symbols and L is the number of symbols in the password. H is measured in bits. However people are poor random generators, cryptographic systems are subject to other lines of attack than guessing, and systems that accept arbitrary size passwords generally do so by converting them by a Cryptographic hash function. A secure hash of a million-character password is neither harder nor easier to guess than the hash of a two-character password. There is therefore little point in constructing a very long password to achieve an entropy much higher than is required for the situation (256-bits or 64 hexadecimal digits or 32 character bytes is regarded as secure against casual attacks), the system will never have greater security than is given by the length of its hash function, and use of very long passwords may introduce other weaknesses such as difficulties and delays in remembering, storing, updating and legitimately conveying the password, and will bloat of the message bandwidth. Blooteuth (talk) 17:42, 29 January 2017 (UTC)

I remember a funny conversation at [11] where I noticed that Kaspersky's password checker could tell me that a password was super secure, then change its mind as I typed more characters. A reason was that a longer password might be one of the 10,000 most common passwords while a truncated one didn't come up on that list. In any case, password strength is sort of a black art, not really a science, since it's predicting behavior. I bet the NSA really does check to see if you used the entire preamble to the Declaration of Independence as your passphrase... Wnt (talk) 02:22, 30 January 2017 (UTC)

Just out of curiousity, did the less-secure-but-longer password form an English word? Simple English words are generally held to be less secure (or perhaps more guessable), so it could be that a nonsense part word 'likin' might be more secure than an English word 'liking', despite being shorter. Matt Deres (talk) 12:10, 30 January 2017 (UTC)

@Matt Deres: I copied the file to Wikipedia:Most common passwords/10000. It contains some real headscratchers: 123qweasdzxc and 8J4yE3Uz for example. More common are entries like PUSSY and knockers ... anything remotely related to sex is one of the most common passwords. Wnt (talk) 23:19, 30 January 2017 (UTC)

@Wnt: Interesting. I'm not surprised 123qweasdzxc is on there; I've used a shorter version of that before on some low-priority passwords, but I'm lost on 8J4yE3Uz. Maybe it's an easy-type password on some other keyboard type I'm not thinking of. Matt Deres (talk) 02:58, 31 January 2017 (UTC)

For a farcical example of the most lax of all password security, see the bizarre success of Gary McKinnon's most primitive of tactics. To quote from our article: In an interview televised on the BBC's Click programme, McKinnon stated that he was able to get into the military's networks simply by using a Perl script that searched for blank passwords; in other words his report suggests that there were computers on these networks with the default passwords active. The MILITARY doesn't think of this problem??? Can anyone explain how this is possible?. Any half-smart system would never allow the use of a "default password". What exactly went wrong here? Has anyone provided any half-credible explanation?

Whatever the explanation, the phenomenon has been widespread and persistent. As described in his autobiographical Surely You're Joking, Mr. Feynman!, Richard Feynman repeatedly demonstrated that he could access military computers (as well as open safes and other combination-protected devices), and was able to do so because he had learned the factory default settings and knew that the majority of military users didn't understand the need to change them.

Historically, miltary handling of computer systems often fell foul of the mismatch between military mindset and civilian nerdthink – my father was involved in the introduction of computers to the then Royal Army Pay Corps, and at one point, after a mixed-rank group had completed a training course provided by the suppliers, the other ranks were all assigned to be programmers and the officers as systems analysts, regardless of their demonstrated suitabilities. {The poster formerly known as 87.81.230.195} 94.12.94.189 (talk) 16:27, 30 January 2017 (UTC)

The obvious problem is that "civilian nerdthink" is generally where the real expertise is. Rare is the soldier who can thwart a FBI Ten Most Wanted Fugitives former member Kevin Mitnick. NASA, from I've heard, has an army of "civilian nerds", who, I would presume, are perfectly capable of going toe-to-toe with a Gary McKinnon. Mckinnon's tricks working against a pentagon computer, your explanation fits. But he claims he got into NASA, which would be far harder, ironically, given the nature of their techie staff. Has the American government ever detailed their allegations against him, and whether NASA was in fact hit? Eliyohub (talk) 17:31, 30 January 2017 (UTC)

A bit like not encypting military drone video feeds, allowing anyone with a radio antenna and some downladable shareware software to view the feed in real time Eliyohub (talk) 12:21, 30 January 2017 (UTC)

A lot of internet's first protocols date back from a golden age where a few bearded researchers shared data files across a network and none really thought about security. Fast forward today, high towers have been built on shaky foundations and none really wants to evacuate the tower for renovations.

Take for instance BGP hijacking. The way routing works is that everyone in the network knows in how much time they can pass a message to their neighbours, and announce it loudly. From the annoucements of your neighbours you can guess how much time you would need to reach your neighbour's neighbour, etc. If A tries to send B a message over the network, A will look among her neighbours which one advertises the shortest time to B, and each successive handler of the packet should do the same until the packet reaches its destination. The problem is that M could falsely claim that he is very very close to B, in order to force the packet go through him (either to eavesdrop the connection, or to censor it).

If a routing protocol was built from scratch this attack would be trivial to eliminate. For instance, everyone signs who is their neighbour and how much time they need to reach any destination, the whole thing is published, and unless there are too many liars it is pretty obvious to spot who tried to hijack traffic (the "second solution" of Byzantine_fault_tolerance#Early_solutions even claims there is no such thing as "too many" if crypto is available). I just made that strategy up, so there probably are easier/faster/better ways to do it. The point is that from basic cryptography your can eliminate the attack, but none thought it would even be necessary when the protocols were designed. Tigraan^{Click here to contact me} 13:20, 30 January 2017 (UTC)

Is there a term for the continents excluding Antarctica?

Is there a word to describe the continents with the exclusion of Antarctica? I came across the phrase "every inhabitable continent" but Antarctica has 135 permanent residents. "Every non-polar continent" sounds better, though Antarctica is only partially within the Antarctic Circle. Any ideas? - Reidgreg (talk) 17:28, 29 January 2017 (UTC)

What's wrong with "the continents excluding Antarctica"? ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:55, 29 January 2017 (UTC)

Antarctica does not have any permanent residents, all research station personnel are seasonal, nobody stays for more than a year. Roger (Dodger67) (talk) 18:00, 29 January 2017 (UTC)

Our Antarctica article does claim 135 permanent residents, but provides no source, and the Population section and separate Demographics article provide no support for the claim. The figure is found on various other websites, but from a cursory look, none that might not have copied it from here.

As for the actual question, I'd go with habitable continents. Antarctica is only habitable in the same sense that space is. Henry^Flower 20:41, 29 January 2017 (UTC)

p.s.: looking at the talk page for the article, it seems that the claim was added last year, by an editor with an idiosyncratic interpretation of "permanent resident". Henry^Flower 20:47, 29 January 2017 (UTC)

Disagree. Antarctica is habitable in the same sense as, say, New York City is--you've got to wear warm clothes and have heating. Loraof (talk) 20:45, 29 January 2017 (UTC)

Only in winter. Henry has it right. Antarctica is no more habitable than the Moon. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:03, 29 January 2017 (UTC)

If New York is inhabitable all year round, then so is Antarctica. And you can breathe the air in Antarctica but not on the Moon. Loraof (talk) 21:21, 29 January 2017 (UTC)

The area we now call New York was inhabited by aboriginal peoples for thousands of years prior to the development of modern conveniences. How many aboriginals inhabited Antarctica? ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:30, 29 January 2017 (UTC)

That's a red herring. As far as we know, the place was only first visited by humans in the 19th century. But had Inuits somehow found their way there, they probably wouldn't have had too many problems. -- Jack of Oz ^{[pleasantries]} 21:42, 29 January 2017 (UTC)

Then what is the basis of the OP's question? ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:27, 29 January 2017 (UTC)

People can stay more than a year. In US-based stations, employee contract are seasonal (usually divided into winter and summer blocks), but there is no prohibition on stringing together longer stays. Of course, most people choose not to do that, and the winter work force is much smaller than the summer, but there are a few people that have strung together multiple years on the ice. Dragons flight (talk) 21:17, 29 January 2017 (UTC)

Can they bring their family? Personal ad: Likes long walks on the ice cap, snowboarding, snowshoeing, snowmobiling, being able to do it almost anywhere.. Sagittarian Milky Way (talk) 00:05, 30 January 2017 (UTC)

Demographics of Antarctica lists the names of those actually born in Antarctica (as part of Argentine and Chilean attempts to strengthen claims), and indicates a winter population of about 200. Wymspen (talk) 10:51, 30 January 2017 (UTC)

If I had a wife I certainly wouldn't volunteer to spend multiple years there without her. Sagittarian Milky Way (talk) 11:22, 31 January 2017 (UTC)

• A lot of things that we can conceptualize, like "bleached-blond gay campus lecturers" could have a single word, but you have to consider epistemological economy. Having a word for everything is simply too much of a cognitive burden when phrases will do. If you were writing a book comparing Antarctica to the rest of the world you might coin an acronym, like EAC's for extra-Antarctic continents for convenience's sake. Ayn Rand's Introduction to Objectivist Epistemology has a chapter addressing this issue. μηδείς (talk) 21:06, 29 January 2017 (UTC)

Nothing to see here. Collapsed by TigraanClick here to contact me 10:24, 31 January 2017 (UTC)

I think you had everyone until the last sentence. --Jayron32 11:53, 30 January 2017 (UTC) You need to grow up, Jayron; develop a thick skin and the ability to separate your emotions from your critical thought processes. Criticizing a valid answer that sites a perfectly relevant source because you don't like the politics of the source (who's making an entirely non-political argument) is something out of Cultural Marxism or the Middle Ages. Read the book, and then get back to us. My undergrad philosophy major advisor told me it was the best philosophy book he had read in 10 years, and he had no idea who Rand was. μηδείς (talk) 17:04, 30 January 2017 (UTC) Oh, Lord, I tried to read Ayn Rand once, back when I was far more sympathetic to her politics. OMFG I could have emptied a revolver into her book and no bullet would have made it even a third of the way through! Wnt (talk) 23:36, 30 January 2017 (UTC) Neither of you has read the book I have referenced, it is well under two hundred pages (the second edition has large appendices). This really should be hatted as off-topic ad hominem totally irrelevant to the question at hand. μηδείς (talk) 23:54, 30 January 2017 (UTC) As it was you than brought up A R why don't you hat it all?--Aspro (talk) 00:19, 31 January 2017 (UTC)

January 30

Toulouse botanical gardens

Jardin des Plantes, Toulouse and Jardin botanique Henri Gaussen are distinct botanical gardens, aren't they? --Djadjko (talk) 02:47, 30 January 2017 (UTC)

Actually, I'm looking at Google Maps and it shows them as one and the same. (Jardin Royal is a separate botanical garden, though, being on the other side of the street.) 2601:646:8E01:7E0B:904E:8E2E:48D1:CC6E (talk) 03:12, 30 January 2017 (UTC)

Nevertheless, it appears they are different; but they are adjacent, with the Henri Gaussen garden located along the northwest side of the Jardin des Plantes. Admission to the Jardin des Plantes is free, as you can also confirm from its open-style entrances. Admission to the Henri Gaussen garden, however, is included when you pay to see the Toulouse Museum: see here (bottom of page, under "billetterie") or here (right side of page 2, bottom of box). The coordinates in Wikipedia for the two places confirm their relative positions. I think the articles about both gardens (in both English and French) should clarify the relationship between them. --76.71.6.254 (talk) 09:31, 30 January 2017 (UTC)

Are wind patterns guaranteed not to change

Imagine you are considering an investment on a wind farm in a particular location (say, West Texas). Is it possible that global wind pattern changes make the wind farm obsolete before the turbines become obsolete? Thanks! Brusegadi (talk) 05:58, 30 January 2017 (UTC)

Where weather is concerned, nothing is guaranteed. But weather data can suggest trends. ←Baseball Bugs ^{What's up, Doc?} carrots→ 06:18, 30 January 2017 (UTC)

You might check the global warming article to see if that is predicted to change global wind patterns. Loraof (talk) 16:47, 30 January 2017 (UTC)

No, there is no guarantee of wind patterns persisting, yes, it is possible that wind patterns may shift significantly at some locations. From the IPCC report (2007)[12] "Mid-latitude westerly winds have strengthened in both hemispheres since the 1960s." Also "Changes in sea surface temperatures (SST), wind patterns, and decreased snowpack and snow cover have also been linked to droughts."

"Discernible human influences now extend to other aspects of climate, including ocean warming, continental-average temperatures,temperature extremes and wind patterns".

Recent research suggests " The tropical easterly trade winds are expected to weaken" [13].

Fine detail of specific local effects of climate change remains a challenging field of research, and I do not know of any research suggesting they can predict small-scale changes in wind patterns. SemanticMantis (talk) 19:49, 30 January 2017 (UTC)

I think I'd start by researching the effect of climate on the Hadley cell, which itself is subject to debate. But if the boundary of the Hadley cell moves north, then the position and intensity of the trade winds might change. How this affects a wind farm... hard to say. But maybe someone can... Wnt (talk) 23:27, 30 January 2017 (UTC)

Winds in west Texas will be tied to changes in the Great Plains low-level jet. There was an article on predicted 21st century changes to the Great Plains LLJ a few years ago. (here). Shock Brigade Harvester Boris (talk) 00:47, 31 January 2017 (UTC)

Thanks everyone! This was something I had never thought about and wanted to see what was out there - but my search skills were not up to par to find something definitive. A slightly different question... do you think that in certain areas its almost certain there will always be wind? For example, the shore? Thanks! Brusegadi (talk) 05:37, 31 January 2017 (UTC)

• Yes, sea breeze is guaranteed to happen once (one back-and-forth) per day when a large enough body of water is close to a large enough body of land.

It does not mean, however, that a wind farm near the cost is a surefire investment. Instantaneous wind power scales as the cube of wind speed, so from a pure efficiency point of view it can be better to have strong gusts of wind now and then than a steady wind (see e.g. [14]). (BTW, I think this is the reason wind farms are often stopped when you look at them: they are designed to work for a specific range of speeds because of the weight/friction vs. mechanical resistance tradeoff, and you can sacrifice a lot of the low-speed range to extend the high-speed range because of that cubic factor.) Tigraan^{Click here to contact me} 10:36, 31 January 2017 (UTC)

Actually, the opposite is true. Often wind farms are stopped because the wind is too strong, so they've engaged their brakes. (You can find spectacular videos on YouTube of turbines whose brakes have failed on a windy day.) They do this, because as you say, power is the cube of wind speed, so making the turbines capable of withstanding those high speeds would be very expensive, and it would be a waste of resources if the local weather only occasionally reaches those speeds.

This is discussed very briefly in the Wind turbine design article, but I wish it went into it more. ApLundell (talk) 14:20, 31 January 2017 (UTC)

They used to build huge windmills to grind flour everywhere. These where huge investments back then noone had done if wind patterns would change in a way that could make these windmills obsolete. So in general wind doesnt change more then the weather. So as its also always possible that it will not rain somewhere for some time, it wont stop raining forever unless you pick a very bad spot (like at the edge of a desert). --Kharon (talk) 22:53, 31 January 2017 (UTC)

Non-dairy creamer is not sweet

Little plastic container

Why isn't non-dairy creamer when it contains lots of corn syrup. I see in some brands, corn syrup is a main ingredient or the main ingredient. Some baby formula seems to be the same: lots of sugar but not sweet. Anna Frodesiak (talk) 12:43, 30 January 2017 (UTC)

They're at least mildly sweet to me. Maybe it's cause the slow dissolving spreads out the taste over more seconds than if the non-sugar parts weren't there. Sagittarian Milky Way (talk) 13:16, 30 January 2017 (UTC)

• De gustibus non est disputandum. It tastes sweet to me. --Jayron32 13:23, 30 January 2017 (UTC)

Yes, opinions/tastes vary. I wonder what brand you are thinking of? Aren't you in China? If so, I'd suspect the regular non-dairy creamer might be a little different than what we commonly see in the states vs. AU or EU (just like we have slightly different teas and colas etc.). Also corn syrup comes in various concentrations of sugar. High fructose corn syrup has attracted a lot of criticism recently, but that's not necessarily what is in your non-dairy creamer. SemanticMantis (talk) 16:05, 30 January 2017 (UTC)

Maybe it's my taste buds (The Taste Buds would be a good name for an all-male swing band). I find coffee mate, generic brands of the same (whether here in China or elsewhere), and those teeny plastic containers not sweet at all. Maybe it's just me. Anna Frodesiak (talk) 23:09, 30 January 2017 (UTC)

The article says it can vary. Traditionally coffee was sweetened with "cream and sugar". The creamer technically duplicates the cream only, but cream e.g. whipped cream is often sweetened (technically "cream" by itself should be no sweeter than the milk it was skimmed off of!) And people like convenience, and sweet stuff. It all leads to sweetened creamer, I suppose. Wnt (talk) 23:33, 30 January 2017 (UTC)

"Sugar" is a broad category of substances with differing levels of sweetness when consumed. Plain corn syrup is mostly glucose, which (as you can see from the table in sweetness) doesn't taste as sweet as fructose or sucrose (a.k.a. "table sugar"). This might be the reason, though to be certain we'd have to see the ingredient list of the sweetener in question. (Anyway coffee isn't worth drinking if it's not black as night. ) --47.138.163.230 (talk) 10:55, 31 January 2017 (UTC)

Sugar is sometimes added to foods to counteract bitterness. I know some milk proteins are very bitter, but I can't quickly figure out exactly which proteins go into non-dairy creamers.

That might yield a clue, though. Figure out exactly what ingredients go into the creamer you're interested in, and see if any of them are known for being very bitter. If so, that would explain the presence of sugar you can barely taste. ApLundell (talk) 14:10, 31 January 2017 (UTC)

Just to clarify when you say "I see in some brands, corn syrup is a main ingredient or the main ingredient", you're referring to the products you're actually tasting, not the ingredients of other brands or ingredient lists from the same brand in other markets? Nil Einne (talk) 14:23, 31 January 2017 (UTC)

Hi Nil Einne. I'm referring to products I'm tasting. All those liquid or powder creamers/whiteners don't taste sweet to me, nor does baby formula with sugar as a main ingredient. Anna Frodesiak (talk) 20:12, 31 January 2017 (UTC)

• Also relevent to the "De gustibus..." comment that I made above is the notion of the supertaster. To go along with the things people note above about "bitterness", is that some people have a much higher sensitivity to bitterness; so that the overall "taste profile" of something for those people can be very different than for people without such bitterness sensitivities. In other words, where such bitter notes overtake the overall taste, the impression can be less sweet. Also, since taste is a type of qualia, rather than being a quantifiable, repeatable phenomenon, there really is no way to make reliable comparisons. We can speak in trends, as to how many people in a population may or may not experience tastes, but ultimately, the sensation of taste is a personal issue, and your tastes can not necessarily be compared to another person's in such a was as to reliably associate specific tastes with specific chemical make up. In other words, you cannot rely on your own tastes to judge exactly how the entirety of humanity will also taste the same thing. --Jayron32 15:20, 31 January 2017 (UTC)

Hi Jayron32. I guess you have a pretty good point with "De gustibus..." It seems like most others find the stuff sweet. I find Marmite quite disgusting, but I imagine others find it only slightly disgusting. Anna Frodesiak (talk) 20:12, 31 January 2017 (UTC)

Oh, come off it. I doubt anybody really likes Marmite; they just pretend to as a way of pointing out how cultured they must be on account of not being American. Any product whose history involves the sentence "a scientist discovered ... could be eaten" is not actually as good as people say. :) Wnt (talk) 23:39, 31 January 2017 (UTC)

Thank you all for the thoughtful replies. It is much appreciated. Anna Frodesiak (talk) 20:12, 31 January 2017 (UTC)

January 31

Which parts of one's brain can trick one into thinking that one is thirsty and/or fatigued/exhausted even though one isn't?

Which parts of one's brain can trick one into thinking that one is thirsty and/or fatigued/exhausted even though one isn't actually thirsty/fatigued? Futurist110 (talk) 04:54, 31 January 2017 (UTC)

The question isn't worded very well, because if "thirsty" means "desiring fluids" and fatigued means "desiring rest" then no trickery is possible -- thinking you are thirsty means that you desire fluids and therefore actually are thirsty. So let's refine the question into something more meaningful: which parts of the brain can give rise to a desire to drink when the body does not actually need fluids, or a desire for rest when the body does not actually need rest? The first answer is the cerebral cortex, because that is where complex cognitive interpretation of sensory inputs takes place, and errors in interpretation can give rise to dysfunctional desires. (As a concrete example, there have been cases of marathon runners dying from drinking too much water. They were actually salt-deprived and started feeling bad because of it. They interpreted the malaise as thirst and responded by drinking water, causing them to be even more salt-deprived, therefore felt even worse, therefore drank more water, etc.) It is also possible for disorders in subcortical structures to give rise to dysfunctional desires, but the structures in question are specific to the type of desire. (For example dysfunctions in parts of the hypothalamus can give rise to a desire for food in people whose bodies don't really need any.) Looie496 (talk) 16:30, 31 January 2017 (UTC)

Great answer, and I happen to know that you're an expert in neuroscience, so I believe you. But if we wanted to read more on the topic, where should we go? I found this [15] article that discusses "dysfunction of the thirst regulatory mechanism", but it's not exactly easy reading for the general public, and it's also behind a paywall. So if you or anyone else has more suitable accessible references, I'd appreciate it! SemanticMantis (talk) 17:15, 31 January 2017 (UTC)

I learned the Parasympathetic_nervous_system is responsible for all that and more. Im far away from real medical profession and knownledge tho. --Kharon (talk) 22:39, 31 January 2017 (UTC)

Use of definite article "the" before names of biological features

In Secretin#Discovery, it is written as "It was known that the pancreas secreted digestive juices in response to the passage of food (chyme) through the pyloric sphincter into the duodenum."

Notice use of "the" before pancreas, pyloric sphincter and duodenum. Notice omission of use of "the" before digestive juices.

In Human_digestive_system#Salivary_glands, it is written that "The largest of these are the parotid glands – their secretion is mainly serous. The next pair are underneath the jaw, the submandibular glands, these produce both serous fluid and mucus. The serous fluid is produced by serous glands in these salivary glands which also produce lingual lipase. They produce about 70% of the oral cavity saliva. The third pair are the sublingual glands located underneath the tongue and their secretion is mainly mucous with a small percentage of saliva."

Notice use of "the" before parotid glands in the first sentences, and before sublingual glands and tongue in the fifth sentence. Notice omission of "the" before serous in first sentence, serous fluid and mucus in second sentence, serous glands and lingual lipase in third sentence.

This kind of arbitrary use of definite article is confusing. Is there any rule on this? --IEditEncyclopedia (talk) 05:15, 31 January 2017 (UTC)

This is more of a linguistic question than a scientific one, but it is standard to refer to an anatomical feature in terms of an ideal one in a perfect, theoretical body. That it what the use of the definite article implies. —Μετάknowledge^{discuss/deeds} 06:35, 31 January 2017 (UTC)

The use of "the" when speaking of a substance like saliva or blood tend to suggest all of it. Consider the difference between "I drank water" and "I drank the water" - the second one suggests that you didn't leave any for the next person. So you say "the pancreas" because it is a single organ, but not "the digestive juices" as the pancreas does not secrete all of them, just some of them. Also, bear in mind that "serous" and "mucous" (rather than "mucus") are adjectives, not nouns. Wymspen (talk) 09:36, 31 January 2017 (UTC)

Definite articles can also be used to indicate specificity; I drank water does not specify which water. I drank the water specifies which water has been drunk, specifically some specific water that was previously established by context. The distinction here, however, is the difference between a discrete object and an uncountable substance. Mass nouns don't take the definite article unless one is trying to make some specific statement about it. Discrete objects do. So "I put gasoline in the car" is the analogy here "I put gasoline in car" is poor grammar regardless, and "I put the gasoline in the car" means you are clarifying the word "gasoline" to indicate amount or specificity. It's the same with "saliva" and "the pancreas" here. --Jayron32 16:30, 31 January 2017 (UTC)

Medicine school duration in French is indeed 9 years?

I saw this information but it doesn't make sense for me, especially according to what I've read on the article medical school on Wikipedia. In addition it's totally different from most other countries of Europe that they have 6 year program93.126.88.30 (talk) 21:02, 31 January 2017 (UTC)

Speculation here, but I'm guessing that the 9 years includes what we in the US would call a combined undergraduate and medical degree program. Your link says that in the first two years the students study humanities, social sciences, law, foreign languages, and computer science in addition to medical things. Loraof (talk) 22:00, 31 January 2017 (UTC)

The content at the link provided (which needs some copy-editing, and probably should be taken with a grain of salt in case something was lost in translation) breaks down the program into three "cycles".

• Cycle one (two years) appears to correspond roughly to a two-year undergraduate program tailored to subsequent medical study.
• Cycle two (four years) looks a lot like a typical four-year M.D. program.
• Cycle three (three years or more, depending on specialization) appears to be the usual sort of residency program.

If I had to guess, I'd suggest that the confusion about the duration of the program arises because this site is counting the time spent in residency in its total. TenOfAllTrades(talk) 00:47, 1 February 2017 (UTC)

If you think about it, to become a doctor in medicine, 9 years is not very different from a French doctorate, which is 8 years (4 years for "Maitrise", 1 year for the "DEA" (research preparation year), then 3 years for a PhD). --Lgriot (talk) 10:56, 1 February 2017 (UTC)

February 1

Human Respiratory system

Hi I want to ask you about that

The wall of left ventricle of a human heart is thicker than that of the right ventricle.Why?Give reason

Thanks Sawongam (talk) 06:15, 1 February 2017 (UTC)

Sorry, we don't do your homework for you. 2601:646:8E01:7E0B:1C2B:1B0E:6B82:7D00 (talk) 06:19, 1 February 2017 (UTC)

First of all please note a heart is not a part of a respiratory system but rather of a circulatory system. --CiaPan (talk) 07:35, 1 February 2017 (UTC)

Name for length of time that data is recorded for

(I'm not sure if this is a science, maths of language question, so apologies if this is the wrong place to ask this). I'm writing a report and want to say something to the effect of "the instrument recorded good data for two periods, A and B, plus a third period C where the values were incorrect". However, I don't want to use the word "period", because that could cause confusion with both the logging interval, and the periodic variation of the data. (Especially as part of the problem with the bad data is that the periodicity doesn't match reality). What would be a good alternative term to use? Iapetus (talk) 10:29, 1 February 2017 (UTC)

• (edit conflict)I think "acquisition" is the best with a workaround here: Three acquisitions were made: A and B (where data was good) and C (where values were incorrect). After all, you are not really talking about duration but rather about the set of time (not sure if that's clear; if you can speak German, that's the same distinction as hour = Stunde/Uhr). In a more general context, "acquisition time" usually refer to the length of time of one experimental recording. Tigraan^{Click here to contact me} 10:39, 1 February 2017 (UTC)

Your wording would strongly risk implying there were only 3 recordings of data, not two time periods were acquisition of data was good and one time period where it was incorrect. Nil Einne (talk) 13:08, 1 February 2017 (UTC)

Would replacing "for two periods, A and B" with "during two periods, A and B" make the meaning clearer for your purpose? --100.34.204.4 (talk) 13:46, 1 February 2017 (UTC)