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August 10

Rapid spiderling growth

A few weeks I noticed a female Daddy longlegs (mommy longlegs?) with an egg sack in the corner of my bathroom. Now, normally any spider is gross enough to get an eviction, promise of yet more spiders most assuredly included. But this particular spider had only five legs and I figured she'd earned a rest, so I left her alone. About a week ago, the eggs hatched. At first they were so small it was difficult to make out their indivual legs with the naked eye, but just one week later, they have almost tripled in size. And yet, no immediately obvious prey or other source of nourishment. So my question is this: where is all of this mass coming from? Are the babies born with metabolic reserves in a more compact form, which energy they can tap to quickly develope? Or does the mother provide some kind of nourishment? Spider says mothers in some species will regurgitate food for young, but it is unclear if they only do this with recently caught prey; there has been no immediately obvious prey of any size in or below the web, but I can't rule out a quick snack has been missed. Thoughts? 2001:4B98:DC0:47:216:3EFF:FE3D:888C (talk) 12:03, 10 August 2017 (UTC)

Only 2 cents thoughts. The most simple is usually the better: they eat prey according to their size, that you cannot see (including their own bro, maybe), but you probably thought it yourself already. Also, spiders may eat silk, and things (living or not) that got stuck to it, that may be significant food for a small enough spiderling. And, obviously, most new mass will come from water, considering the water proportion in living being. I hope someone will bring some better answer. Gem fr (talk) 12:33, 10 August 2017 (UTC)

Prey as small as that are unlikely to be caught in most Pholcidae webs as they do not have strong adhesive quality; their webs are arranged by filaments suspended at every convenient angle, so as to entangle prey, but prey so small as to be tiny compared to even the young spiders described by the OP are unlikely to be caught by such webs. Some spiders do consume their webs, but rarely do they have much nutritional value; more often they do it in order to adjust their nests. I think the OP's original guess is most likely to be right; these spiderlings are probably just developing from their original high-energy reserves. Consider that they do, afterall, develop from embryo to post-embryo (hatchling) without consumption. Also, often the legs of spiders will develop fastest in the first molts; this results in their appearing to grow faster than they in fact are in the aggregate, because the legs, while not a huge additional amount of mass, lead to a significantly larger leg-span and thus perceived diameter.

All of that said, the OP should be on the look out for these spiders to disperse soon. Spiders are highly famine resistant creatures (they are capable of entering into period of highly prolonged and substantial stillness, thus modulating their metabolic rate), but the one exception is early life, for exactly the reasons the OP is noticing here: A) they are developing and burning through their reserve energies and B) they are relatively helpless to collect prey. They make up for this in part by having large numbers of offspring, some of which will be more fortunate than others in securing those early meals, possibly using their mothers nest (though, to my knowledge, Pholcidae do not share captured prey with anyone, not even family), but more likely after securing their own. Cannibalism is also quite common among the young of many species. The Pholcidae family is also known for their willingness to tresspass into the webs of other spiders to steal their food or even kill the inhabitants and/or eat their eggs, so there's that too. Here's some useful additional reading: [1], [2], [3] Snow ^{let's rap} 13:39, 10 August 2017 (UTC)

Shivering

At what temperature does shivering start at? Assuming wearing light clothes. — Preceding unsigned comment added by 5.200.42.234 (talk) 14:20, 10 August 2017 (UTC)

It is not a set temperature. Some people lose the shiver response due to age or injury and never shiver. Some people shiver when hot (fever chills). Normal shivers are triggered by core body temperature vs skin/spinal temperatures and vary from person to person. 209.149.113.5 (talk) 15:37, 10 August 2017 (UTC)

An HVAC book may have that study where they kept people at various temperatures for hours/temperature and I think the average was around 55°F. Sagittarian Milky Way (talk) 16:05, 10 August 2017 (UTC)

You can train yourself to not shiver and tolerate extreme cold much better, see here, and here, and here. Deep and fast breathing exercises are important if you want to tolerate extreme cold for a long period. In the beginning you'll hyperventilate when doing that, but you then train the body to burn the oxygen and produce more CO2 whenever you start breathing like that, thereby increasing the metabolic rate significantly. This allows you to sit naked in ice cold conditions without shivering, you're breathing faster and burning not the usual 100 Watts but 300 Watts or even more. Count Iblis (talk) 19:47, 10 August 2017 (UTC)

• Shivering can be a response to illness, or to perceived heat-loss through the skin, not just a low core temperature. I have reported before, my father recounts working on a windy day in West Texas in the 1960's. The temperature was 70, and him being 6'2" and weighing 250 lbs, that would have been a comfortable day in the Philadelphia shipyards where he apprenticed. But the humidity was 02% and he started shivering as soon as he got out of the car at the worksite, and had to get a winter coat (to a Philadelphian) to work outdoors. μηδείς (talk) 01:59, 12 August 2017 (UTC)

Is there a phobia of being in a building much narrower than it's tall?

Sagittarian Milky Way (talk) 15:34, 10 August 2017 (UTC)

Nearly every named "phobia" you've ever heard of is a product of folk psychology and is not a recognized mental disorder, as defined by actual psychologists, such as the DSM-5. The only types of phobias widely recognized are social phobia, specific phobia, and agorophobia. There are hundreds of dubious sources that will claim to give faux-Greek names to phobias (like "coulrophobia", fear of clowns) but these are NOT recognized by medical professionals as distinct disorders, instead they are all classified under one of the other phobias. A fear as specific as you name is known as a type of specific phobia. --Jayron32 16:04, 10 August 2017 (UTC)

One of Steven Wright's early jokes was, "I was out walking my dog today... on the ledge. Some people are afraid heights. I'm afraid of widths." ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:37, 10 August 2017 (UTC)

Mother of all arachnophobia

Recently I was reading a funny story about arachnophobia - a woman on a field expedition was climbing a steep hillside and abruptly backpedalled, frantic, finally yelling a distressed cry of "Sp-i-i-i-der!" And yet --- it turned out her fear was entirely justified, because the story occurred in Australia. Unlike in the U.S., where arachnophobia is a joke, almost seen as a psychiatric ailment, everything in Australia is apparently out to kill a person with poison. Which got me to thinking...

I have read that other primates have specific distress calls for poisonous spiders. Obviously any spiders of relevance would have had to be encountered by human ancestors in Africa. So ... is it possible to identify the one and only specific kind of spider, against which all human arachnophobia is directed? Is this thing perhaps more inherently terrifying than any other kind of spider, things that merely resemble it?

Starting with such ahem reliable sources as [4], I am directed in the direction of button spiders. There are images like at the top of this article which suggest that oh my, that is one scary looking spider. But can someone here do better, provide some compelling context that makes it out as the definite culprit, or proposes alternative suspects? Wnt (talk) 20:31, 10 August 2017 (UTC)

Deaths or serious injuries from spider bites are very rare even for mentioned black widow spiders. So, this can not explain arachnophobia. Ruslik_Zero 20:57, 10 August 2017 (UTC)

It still probably hurts like hell right? The level of medical technology for most of this subspecies' existence was something like drill a hole in the skull or add leeches. Spider deaths must've been more common then. Sagittarian Milky Way (talk) 22:41, 10 August 2017 (UTC)

I'm assuming that the evolution (or retention) of such an instinct would occur over millions of years. Homo habilis and Australopithecus spp. were generally shorter than modern humans from Homo ergaster on, less than 4 feet I think. I don't know if overall smaller brains would make them more susceptible to a neurotoxin than other humans with the same body mass but larger brains. I should admit that I am susceptible to a crank variant of the old (discredited) aquatic ape hypothesis, in that I am suspicious that human ancestors developed elongated feet and bipedality and fire use in West Africa, in the Okavango delta or nearby (formerly wet) terrain with regular flooding and wildfires; if this is true, then suggesting a black button spider (Latrodectus indistinctus) with the strongest toxin which lives north into Namibia is acceptable - but otherwise (where the known fossils are in East Africa) there could be a problem with the range. This spider (or our closely related black widow) seem like decent options for being 'instinctively' disturbing, but I'm not sure the black button spider is archetypal. Wnt (talk) 01:22, 11 August 2017 (UTC)

Not necessarily answering, but just linking to signalling theory and aposematism, which are somewhat on topic and interesting. —PaleoNeonate – 00:55, 11 August 2017 (UTC)

I just cannot believe that spiders were ever enough a threat to trigger an evolutionary adaptation, and turn arachnophobia into a competitive advantage. As opposed, for instance, to "mosquitophobia" (red link !), THIS would had been, and still be, a real competitive advantage, but doesn't seem very common (if it ever exist).

fear is known to be triggered, among other things, by startling quick movement of the thing; mice and spiders are both capable of this kind of movement: they just stand still, then they surprisingly dart or even jump (Salticidae) in any direction, including yours, and THIS is indeed threatening (even though you may laugh afterward of fearing such a small thing). On the other hand, when you learn (from experience, not from books), that Pholcidae do not move this scary way, you stop finding them scary.

Plus, spiders and their webs are also a thing that will surprise you in scary environments, such like caves, dark wood, or darkness of the night, and trigger Startle response (who here didn't startle when feeling a spiderweb on his face in a wood or a cellar?).

So, for my 2 cents, the simplest explanation of arachnophobia do not involve any genetic memory of any spider of the past, but rather natural association of spiders with fears: surprise movement, and fearful environments (darkness, enclosed space,...)

Gem fr (talk) 09:15, 11 August 2017 (UTC)

Interesting! Might this also be the cause of mottaphobia, given that butterflies also tend to make surprise movements, and some (like the Monarch) are also quite large? 2601:646:8E01:7E0B:21B1:8CA4:6F9F:6132 (talk) 08:33, 12 August 2017 (UTC)

We certainly do have "mosquitophobia", though it is more like "Islamophobia" in terms of the specific emotions involved. The whine of mosquitoes is uniquely annoying (well, maybe not uniquely given that flies have also been made annoying, but it is at least distinctively annoying), their bite distressing, the impulse to swat them universal. The number of mosquitoes is a critical factor that forces participants in survival shows to camp one place rather than another, more than access to food and water. But ... swatting spiders may not work like swatting mosquitoes, and unlike mosquitoes, spiders are readily avoided if one has the right emotions. Given that the bite of a button spider is regarded as a medical emergency according to our article (even though Lonely Planet assures folks button spiders are "harmless"...) I continue to think it is plausible they could arouse this reaction. Wnt (talk) 12:26, 11 August 2017 (UTC)

Formula for walking on gradients

If I burn, say, 100 calories by walking a certain distance on a flat road (0% gradient), is there any formula that allows me to calculate how many calories I would've burnt by walking the exact same distance but on a 5% uphill gradient? --90.69.12.160 (talk) 22:20, 10 August 2017 (UTC)

Find a formula for climbing, multiply your walking distance with 0.05 (5%) and use it as climbing distance and then just sum up both results. --Kharon (talk) 23:09, 10 August 2017 (UTC)

This paper looked at that question: http://jap.physiology.org/content/93/3/1039.full the study was conducted on treadmills. The metabolic cost of walking (Cw) in J/(Kg *m) was empirically determined to be 280.5i⁵-58.7i⁴-76.8i³+51.9i²+19.6i+2.5 where i is the incline.208.90.213.186 (talk) 23:14, 10 August 2017 (UTC)

incline in %?

practitioners of hiking in hill/mountains have a rule of thumb: 100 m up is equal to 1 km, as efforts go. Meaning a a 10% uphill gradient doubles the distance, and 5% increase it by 1.5.

note that this rule of thumb is pretty well in agreement with the study mentioned by 208.90.213.186, provided i is indeed in %

Gem fr (talk) 09:30, 11 August 2017 (UTC)

For time required to walk a certain distance factoring-in gradients and terrain, see Naismith's rule. Alansplodge (talk) 12:26, 11 August 2017 (UTC)

August 11

Why do vanilla ice cream manufacturers have to color the vanilla ice cream?

I think vanilla ice cream is supposed to be white. I made vanilla ice cream in chemistry classes, using two methods. One method was to lower the temperature of the ice in the plastic bag with salt by shaking. Another method was to use liquid nitrogen on the cream. The only ingredients used were half and half cream and vanilla extract. The finished result looked white. Why can't ice cream manufacturers just make the ice cream look white? Why do they add annatto for color? 50.4.236.254 (talk) 01:46, 11 August 2017 (UTC)

Because pure white is a very fragile tone, set off by the tiniest portion of a color, like in Aquarelle starting on a clean white paper. In contrast adding very cheap beta-Carotene for color causes an orange tone which is most appealing and a very good disguise especially for tone setoff's naturally caused by aging (Rancidification) which also usually causes an orange tone. --Kharon (talk) 02:46, 11 August 2017 (UTC)

Milk looks white. Ice cream is derived from milk. So, why is it cheaper to add a color than to keep it the way it is? 50.4.236.254 (talk) 03:10, 11 August 2017 (UTC)

Its not cheaper than not adding anything ofcourse but beta-Carotene is very cheap and very little of it is needed to get the orange on top. They simply dont want to sell white ice cream for multiple reasons and add beta-Carotene for multiple reasons. You cant make ice cream more appealing and cheap any other way. --Kharon (talk) 03:34, 11 August 2017 (UTC)

Note: Real vanilla isn't white, but is rarely used in common ice-cream today, to reduce production costs (more than retail cost). Likewise, real cream is only used in the costly brands, but was also traditionally off-white. If the goal was to make the icecream very white, there would be other options like titanium dioxide. —PaleoNeonate – 03:39, 11 August 2017 (UTC)

What do you mean by "costly brands" and "real cream"? In NZ, Tip Top (ice cream) the retail price where I live in Auckland for a 2L tub of ice cream tends to be $4.50-5.50 although occasionally is available for $4. This would be considered by most to be ordinary ice cream, not the real premium or fancy ones which come in smaller containers and tend to be twice as much or more per L. It's also sold as ice cream meaning it I presume meets the legal requirement of [5] "consisting of not less than 100g/kg of milk fat". (Tip Top also has 55% of the market share in NZ [6], not just from their tubs of course.) By comparison, Much Moore (formerly Kiwi) Marvels brand products are generally $3.80-$4.50 for 2L. Some products under their Marvels brand are ice cream, some are frozen dessert (i.e. either don't have any cream, or don't have enough to meet the legal requirement to be called ice cream in NZ/Australia). Some cheaper products which are I believe all frozen dessert are generally $3.29-$3.79. The Much Moore 'premium' range, which is still just sold in a normal 2L tub is generally $4.30-$5 (sometimes, more often than Tip Top $4) and I believe is all ice cream. Other products tend to be similar price ranges and many of them are ice creams. Admittedly not all ice creams use something which may be called cream in their production, e.g. I believe the Much Moore Marvels range uses milk solids but the point remains most or all of the fat is milk fat. In any case, Tip Top ones do say they use cream e.g. [7]. Some may also use thickeners for various reasons. Nil Einne (talk) 07:28, 11 August 2017 (UTC)

Forgot to mention that Tip Top is of course nowadays owned by Fonterra Co-operative Group one of the largest dairy countries in the world (and who by their dairy coop nature are mostly focused in dairy products, unlike say Nestlé which is a general food and beverage company, or likewise Danone) , so it's not particularly surprisingly they generally use cream or otherwise use milk fat. Nil Einne (talk) 15:30, 12 August 2017 (UTC)

• Most of the vanilla ice cream I've seen is cream-colored, which is to say very pale yellow. On occasion I have seen the heavy yellow vanilla, which is associated here with cheap store brands. Is the yellow ice cream you guys get the norm outside the US? Abductive (reasoning) 06:23, 12 August 2017 (UTC)
  • Vanilla is cream-coloured; that is, it's not pure white. I wouldn't refer to it as yellow. Maybe you're confusing it with the unique NZ variety of ice cream called hokey pokey. Akld guy (talk) 09:26, 12 August 2017 (UTC)

Note that French vanilla ice cream adds egg yolks, making it more yellow: [8]. This is considered a premium version, so it's not surprising cheaper vanilla ice creams may be made to imitate it. StuRat (talk) 16:16, 12 August 2017 (UTC)

Vanilla ice cream is generally yellowish in the UK. Only the very cheap stuff is white. Wall's Ice Cream is probably the market leader here; it lists "Colours (Annatto, Curcumin)" amongst the ingredients, but no actual vanilla. Alansplodge (talk) 17:22, 12 August 2017 (UTC)

Interesting. There seems to be regional variations. Abductive (reasoning) 18:54, 12 August 2017 (UTC)

Metabolism of high-fiber food

I don't understand how dietary fiber affects metabolism and how it affects the stated calories in package labeling in the US.. Consider a bean dish (Gefen Cholent Mix) in which one portion is supposed to provide 70 kilocalories of energy, with 0 fat, 23 grams of carbohydrate, which includes 13 grams of dietary fiber, and 8 grams of protein, per the package's nutritional label. Each gram of carbohydrate should provide 4 kilocalories, as should each gram of protein. The 31 grams of combined carb and protein should provide 124 kilocalories rather than the stated 70 kilocalories. If the 13 grams of fiber (presumably not metabolized by humans) are deducted from the 23 grams of carb, then there would be 18 *4=72 kilocalories of energy per serving., 3% more than the stated amount. Would 23 grams of carbohydrate be converted into glucose in the bloodstream. or would only 10 grams of carbohydrate be converted into glucose? This would seem to be a big deal vis a vis the amount of glucose which enters the bloodstream after such a high fiber meal. Edison (talk) 03:52, 11 August 2017 (UTC)

That's presumably because, as stated in Food energy#Nutrition labels, energy is estimated, and obviously the labeling authorities do not care for few % difference, as they themselves use an official table were, for foodstuff, 4 cal = 17 kJ instead of 16.736 kJ that a physicist would use, that's a 1.5% difference. Add some rounding issues and tolerated variations in content: things will quickly add up to 3% difference you noticed.

Gem fr (talk) 10:05, 11 August 2017 (UTC)

Calories are generally rounded off to the nearest 5 Calories (kcal), which means that for any food greater than 60 Calories (kcal) the 3% would be statistically insignificant, as it would have been rounded off. In the example above, 2 kcal is within the rounding, so it was just rounded off. Statistically speaking 72 and 70 are identical when you're rounding to the nearest 5. --Jayron32 14:50, 11 August 2017 (UTC)

Fiber is metabolized by humans, the USDA gives a value of 2 kcal per gram. Abductive (reasoning) 06:25, 12 August 2017 (UTC)

That depends on if it's soluble fiber or insoluble fiber. StuRat (talk) 16:20, 12 August 2017 (UTC)

Presumably the 2 kcal/g is an average...Abductive (reasoning) 18:52, 12 August 2017 (UTC)

Hmmm, the wiki article says that what matters is whether the fibers are broken down by bacteria and then absorbed by the body, the energy content is then attributed to whatever the body will absorb and metabolize. However, the breakdown of fibers in the gut also releases energy and this is not accounted for at all. Count Iblis (talk) 19:29, 12 August 2017 (UTC)

Eat fewer Calories to lose the weight or eat the same amount or greater Calories to build muscle and thus increase metabolism?

On one hand, people recommend to the general public to eat less. On the other hand, athletes are recommended to eat more to complement the intensive physical activities. Okay, what happens if an overweight person doesn't want to lose weight so he eats the same amount of food (or more, not less) and adds an intensive strength-training and aerobic exercise (such as doing push ups and running) to nourish muscle growth? 140.254.70.33 (talk) 16:32, 11 August 2017 (UTC)

He has better health outcomes. Well, possibly not him, because of individual variability, but if you got some statistically large enough sample of such people, a significant portion of them would have a better quality of life.[9] --Jayron32 17:38, 11 August 2017 (UTC)

You have to note here that being able to burn a significant additional amount of calories compared to the total calorie intake requires being very fit to begin with. E.g. a 60 kg man running fast for an hour will burn roughly 1000 Kcal more due to this exercise. But you won't be able to do this unless you have excellent cardio fitness. Strength training burns only a small amount of energy. That's why body-builders do some cardio training besides the massive amount of strength training. Count Iblis (talk) 17:58, 11 August 2017 (UTC)

A doctor I do research with began his research with an interest in football and studied obese linemen. They are clearly obese, yet they exercise extensively. So, are they healthy? No. Obese NFL players tend to have cardiometabolic syndrome. After retirement, that quickly leads to hypertension, diabetes, and hyperlipidemia, all of which quickly lead to life-ending problems such as congestive heart failure or renal disease. There is a lot (more than you'd think) research on obesity in the NFL, which gets right to the issue of obesity and exercise. Check scholar.google.com. 209.149.113.5 (talk) 19:31, 11 August 2017 (UTC)

I would say that they were not obese when they were athletes, as then the weight was mostly muscle. But, yes, ex-athletes do tend to continue to eat as much, but get less exercise, turning that muscle into fat, at which point they become obese.

As for them being "clearly obese", that sounds like you are only looking at weight, not muscle and fat percentages, although there are some "athletes", like sumo wrestlers, who really are obese. StuRat (talk) 21:55, 11 August 2017 (UTC)

Indeed. Count Iblis (talk) 23:37, 11 August 2017 (UTC)

It is preseason. Watch an NFL game. That flab on the linemen is not muscle. It is fat. They are obese. 71.85.51.150 (talk) 00:40, 12 August 2017 (UTC)

Yes, it is possible that they get "out of shape" between seasons, then "shape up" at the start of the next season. One problem with massive muscles is they take massive exercise just to maintain. Otherwise, they are replaced by fat. StuRat (talk) 01:05, 12 August 2017 (UTC)

As far as I can tell, the 71 IP is not suggesting that linemen have fat not muscle only preseason. I'm not sure why they mentioned preseason but I think they're suggesting perhaps people have forgotten what linemen look like since it's preseason so they should go back to a (non preseason) NFL game. Even if the IP was suggesting that the flab on linemen was fat and not muscle only during pre season, I seem no reason to think that is correct.

I'm under the impression the NFL is a professional sport where atheletes are often paid multimillion dollar salaries. I'm not sure if those salary ranges apply to linemen but at a minimum I'm assuming their positions are still highly competitive. In general, while professional athletes may lose a bit of fitness during the early parts of an offseason, they can't afford to let themselves go as badly as you suggest because they won't be able to recover in time for the season and will find themselves not very popular with the people who can significantly affect their careers like coaches.

According to [10]/[11]/[12]/[13] the average body fat percentage for offensive and defensive linemen was 24.8%. Okay this is for high school and NCAA football players and was during an off-season training season and high school was 26.1% and college was 22.9%. However none of the authors expressed any concerns these players had really let themselves go so they weren't looking at a good sample. (I'd also note that when in the off-season is unspecified. Even if you believe that athletes can get very bad during the first month or so of the off-season, you've surely, I hope, got to realise a month before the season starts athletes need to be close to their peak condition.)

This [14]/[15]/[16] looked at NFL players and suggests offensive line has an average body fat percentage 25.1%. It also says:

The only exception was observed with the offensive line, where values for BMI were higher, accompanied with the classification of ‘‘poor’’ in health estimation, but the %body fat still did not represent extreme values as noted by the BMI.

The extreme here is likely referring to the fact that BMI show them to severely obese category but clearly whether you want to call them obese or not their body fat percentage has reached levels not considered healthy in the general case. Again this was during a summer training camp, prior to the start of the season. I'm not sure how far away the season was, but the authors seem to have similar thoughts to mine:

As such, we felt that each player would be in top condition after an off-season conditioning program and summer minicamps.

Next there's [17] which has results for the 2006 – 2013 NFL Combine testing using Bod Pod and gives 24.6% average body fat for offensive line. Admitedly I'm confused what the source for these figures actually is since that says it's from “Current Assessment of Body Composition in Sport” but I can't find that source. Other places says it's in Sports Med 42(3) but the closests thing there is [18]/[19] "Current Status of Body Composition Assessment in Sport". Anyway I would guess it's just a typo or maybe the title was renamed after pre-release. But more importantly, AFAICT that source doesn't have such figures nor does it have any additional data. And considering it was published in 2012 it would seem weird for it to have 2013 figures. Still the BodPod is definitely used as part of the combine [20] so probably they are somewhere.

Anyway assuming we can trust in-thinair.com to accurately report the figures, wherever they were published, I presume this means the NFL Scouting Combine so technically this is off season too. But considering what the NFL Scouting Combine is for....

Either the athletes go 'you know what, the combine is coming up but I don't have to be in peak condition because it's offseason so let's not worry that this moment could make or break my life and if I was only able to keep it I'll be much more impressive since after all at least the next dude will have the same attitude as me so while I may not be better than them even though I could be, I won't be worse'. And the coaches, scouts etc say 'hey that guy is fat, but I'm sure he just let himself go in the offseason and will regain it over the next few months, let's not worry about our experience or the whole purpose of this combine; you know as that person on the RDS said, it's normal for people to let themselves go so badly out of season.'

Or these people are in top condition for assessment during the combine. (Of course it's possible that being fat is seen as impressive by observers during the combine, but is actually bad while playing but this seems to make further weird assumptions.)

Nil Einne (talk) 06:30, 12 August 2017 (UTC)

BTW, I noticed [21] in my research but it doesn't directly relate to the body fat percentage issue although I just noticed it does mention an absolute weight limit at college level which may affect the earlier figures. Looking a bit more it seems that the size of linemen is a concern in both American [22] and Canadian [23] football. I'd note that the middle source claims as those the earlier links, as well as the middle source just now both claim the linemen size has significant increased over the past few decades. Although interesting [24] it could be going down again, for reasons unrelated to health concerns. Also about Bod Pod and similar measurements, I should mention that one thing the Sports Med source does say backed by an RS is is that such devices tend to underestimate body fat for college football players (I assume this is American, or maybe Canadian since I don't think anywhere else would refer to college football players) by an average of 2%. So assuming the above figures are unadjusted, they may be a little on the low side. Although an average of 2% needs to be taken with caution if we're talking about people with fairly different body types depending on their precise position, which the differing body fat percentages suggest is the case. 07:05, 12 August 2017 (UTC)

Maintaining that level of muscle mass during the off-season would require that they exercise just as much as they do during the regular season, which is basically a full-time job. So, it's not exactly being lazy to not keep up. Do you do the same amount of work when on vacation as when at work ? StuRat (talk) 16:26, 12 August 2017 (UTC)

I mentioned that it was the preseason to indicate that it is very easy to find a video or even a photo of an NFL lineman right now. Look at Dontari Poe. There is a photo of him, during the season, when he is "in shape" right on the page. Look at his lower abdomen. That is not muscle bulging out. That is fat. Yes, he does have a lot of muscle. He also has a lot of abdominal fat. That is the norm for linemen. They have a lot of abdominal fat. You have to be very stubbornly ignorant to look at the photo of Dontari Poe and think that his spare tire is all made of muscle. I would like to have more examples right here on Wikipedia, but I've noticed that there is a distinct lack of uniform photos for linemen. I checked Albert Haynesworth, Jerome Bettis, Dan Wilkinson, etc... I didn't even go after other positions, such as Jared Lorenzen, who I believe is the most obese quarterback ever signed in the NFL. I feel that only someone who has never watched an NFL game can claim that linemen are not obese. However you want to measure obesity, when your belly is hanging inches over your belt, that is fat, not muscle. I'm not saying it to fat shame. I am trying to point out that those players are exercising daily. They are athletic. They have a lot of muscle. But, they are still obese and they still have obesity-related diseases. 71.85.51.150 (talk) 18:41, 12 August 2017 (UTC)

They exercise, but not like this. Count Iblis (talk) 18:50, 12 August 2017 (UTC)

• See an endocrinologist who specializes in weight loss/body mass index. There are various metabolic disorders as 209 noted that you cannot self diagnose, and we certainly cannot diagnose. He can recommend a nutritionist and medication. Then folow his advice on exercise, under a licensed trainer. Don't ask for medical advice here. μηδείς (talk) 21:47, 11 August 2017 (UTC)

Is any new research still done with optical microscopes?

If not, what was the last time it was? Sagittarian Milky Way (talk) 17:26, 11 August 2017 (UTC)

This very day, I'm quite sure my wife used one. She's a forensic scientist who does microscopy as a daily part of her job. She uses a regular old, binocular optical microscope fitted with a camera to record what she sees for evidence. The McCrone Research Institute is probably one of the major players in microscopy in the U.S., and still does work with all sorts of work with light microscopy. So the last time they did active research in the field is quite likely right now. --Jayron32 17:35, 11 August 2017 (UTC)

Probably 95% or research in medicine, biology. geology, etc is done with optical microscopes. --AboutFace 22 (talk) 19:19, 11 August 2017 (UTC)

They certainly are important, but that number is too high for medicine. Don't forget about the vast amounts of work done with molecular biology techniques, and things like Western blots, flow cytometry etc etc. I know a fair few people in neuroscience who never get near a microscope. They are a minority, for sure, but they are more than 5%. Even I, a regular microscope user in neuroscience, don't do 95% of my research on them, I do too many qPCRs for that! Fgf10 (talk) 23:46, 11 August 2017 (UTC)

We used light microscopes daily in my old lab, for everything from insect ID to counting pollen. I think maybe you are undervaluing how useful it is to see little things across many, many fields of inquiry. Nobody in my old lab ever published new research specifically about a new thing that they found with a light microscope, but they certainly published new research that could not have been done without a microscope.

If you want an example of new things recently discovered with a light microscope, check out this [25] coverage of a 2013 Science paper about naturally occurring gearing mechanisms. Sure, the press photo is from an electron scope, but that's just because it is easier to see, looks cool and they had the money to do it. These features are visible under relatively low power, as shown by the video at that link, which is just a normal light scope. This is top-notch, ground-breaking research that basically amounts to "We looked at this small thing with a light microscope and found something really cool that we think all scientists should know about."

TL;DR: yes, lots of research is done every day with light microscopes, probably thousands of people are doing it as I type.SemanticMantis (talk) 19:41, 11 August 2017 (UTC)

I think you meant to link here : [26]

Very cool. ApLundell (talk) 22:55, 11 August 2017 (UTC)

You are mistaken if you think that the light microscopy is some old and stagnant technology that has not changed for a long time. On the contrary new optical methods are actively being developed. Moreover some of them like the fluorescent microscopy earned their creators a Nobel prize. Ruslik_Zero 20:00, 11 August 2017 (UTC)

• You'll have to specify which optical microscope. In my neuroscience research, I use both phase contrast and epifluorescent optical microscopes essentially every day. I frequently use dissection microscopes, and pretty regularly use a confocal fluorescent microscope or two-photon microscope. Conventional bright field microscopy is not used much in my field, but certainly is in others. Take away my optical microscopes and 90% of my research is gone. Fgf10 (talk) 23:43, 11 August 2017 (UTC)

No one has mentioned that many a biological sample would be destroyed or ruined if they were prepared and placed in the vacuum of an electron microscope. Also, did Nikolaus Pevsner have to examine every brick? One uses the right tools for the job. Aspro (talk) 01:00, 13 August 2017 (UTC)

August 12

Finding out the Map Projection

Which map projection is used at this map of the European Inland Waterway Network?

--Baltimax (talk) 01:09, 12 August 2017 (UTC)

Albers projection. Barely visible Latitude lines are round instead of the straight ones resulting in Mercator projections.--Kharon (talk) 03:19, 12 August 2017 (UTC)

How are you so sure it's Albers? Hundreds of projections have round or at least curved lines of latitude (and many other than Mercator have straight lines). 78.234.66.210 (talk) 17:49, 12 August 2017 (UTC)

Yes, see Map projection#Conic. But I don't think it's any conic projection as defined on that page. If you zoom in, particularly on the right-hand side where the longitude lines are farthest from vertical, and look carefully, you can see that when they cross the latitude lines they aren't exactly perpendicular. Really the best way to get a reliable answer would be to contact the UNECE office that issued the map and ask them. --69.159.60.147 (talk) 19:58, 12 August 2017 (UTC)

Language loss

How fast can one lose a language? Back when I was in high school, I learned that Native Americans were forced to assimilate into White-American society. The teacher said that if one can't practice one's own language, then one can lose it in a few months. I personally started learning Spanish in 7th grade and moved all the way up to 12th grade and took two courses in college to fulfill a general education requirement. After the two classes, I hardly practiced Spanish, and somehow I still can remember Spanish words and the Spanish songs stuck in my head. SpanishDict may have a random word of the day, and somehow I'd know them. How is this possible? 50.4.236.254 (talk) 04:16, 12 August 2017 (UTC)

"A few months" is absurdly quick. You might get "rusty", but after returning to people speaking that language you would recall it quickly. However, the age of the person does matter. If you cut very young children off from their native language before it "sets", then they might indeed forget it. StuRat (talk) 04:19, 12 August 2017 (UTC)

Agree with Stu. It is more a case of falling out of the 'habit' of using ones native tongue. There are plenty of anecdotal occurrences of people who fled as refugees to America during War II who thought they had forgotten their mother's tongue only to find during a visit to their homeland (after the fall of the Soviet Union and the reunification of Germany when travel there became easier) it took only two weeks to be talking fluently once more in the language they thought they had long forgotten. The mind is quite plastic at taking off line any memory banks that are currently not required and bring them back online again when circumstances change. Entheogenist find one of the characteristics of drugs like LSD and Ketamine is that they appear to bring all memory banks online -all at once. Yet, after daily doses, the mind adapts (is plastic) and takes them off line again and further dosses have no longer any psychedelic effect. This goes for physical skills as well. One may have not played a piano for many decades but with a little practice it all come back again. Even on those instruments that don't require depressing a key to hit a felt hammer onto strings stretched on a iron frame, in a wooden enclosure , which is all we had before MIDI. And we could still play them during a brownout or complete cut ! Aspro (talk) 10:44, 12 August 2017 (UTC)

Or the classic case of riding a bicycle, which comes back to you after years of not riding. StuRat (talk) 12:55, 12 August 2017 (UTC)

To echo Aspro, I spoke Spanish to age four, along with my native English, since my parents both got by in it and we lived in Puerto Rico where I had a monolingual Spanish-speaking nanny and Texas, where my best friend was Mexican. When I was four-and-a-half, we moved to a town in NJ where the population were all third generation or more Europeans (mostly Irish and Italian) and I got odd looks and no response when I spoke Spanish to people, which led to a few teary incidents. I subsequently "lost" it.

When I was 18, I worked in a kitchen with Filipinos and Mexicans as I went to college. I told them to address me only in Spanish. With the help of 201 Spanish Verbs and my HS French I was basically fluent again in non-literary level Spanish within a few months, to the point of dreaming in it, and finding myself at a loss for an English word on a few occasions. μηδείς (talk) 16:52, 12 August 2017 (UTC)

That's interesting. My first language was Chinese, I spoke it till I was four and since then have only spoken English. I don't even remember ever having spoken Chinese, it would be interesting to try and learn it again. Dmcq (talk) 17:11, 12 August 2017 (UTC)

So it appear that the OP's teacher was just over simplifying things. Was interesting that μηδείς found herself lost for words at times. Think this was not so much 'words' as phrases. The ancient Greek's had a lovely phase that translates into English simply as potter against potter which referred to arguments that arise between two experts who both insist they are right – there is no English equivalent to express that. Also some of the French double negatives such as Je t'aime... moi non plus defeats my ability to translate in real-time. @ User talk:Dmcq. The big problem foreigners have, with learning Chines, is to developer an ear to for the tonal syllables in order to differentiate meaning. If you also have some musical training then getting up-to-speed again in Chines may be even an easier endeavour. Don't expect results over night but if that tonal pattern is still there in your brain’s neural network, then it will be easer to relearn. Aspro (talk) 18:22, 12 August 2017 (UTC)

Just googled this about Chinese: Mandarin Chinese is a tonal language. Also, children who have a tonal language are also better at being pitch perfect when they become musicians like Vanessa-Mae. Aspro (talk) 19:23, 12 August 2017 (UTC)

Well I still have people wondering what my accent is and where I come from so perhaps the ear is still there too :) Dmcq (talk) 21:50, 12 August 2017 (UTC)

I wonder if people who are tone deaf have difficulty speaking Chinese. StuRat (talk) 18:54, 12 August 2017 (UTC)

Good question. They might be viewed upon in the same way that dislektiks dieslettics dyslolectics dyslexic's are treated in the west. We need an academic of tonal languages to comment on this. Even dyslexic's who have trouble with the written words have trouble sometimes with pronouncing words write right. Yet, mother nature appears to endows them with other gifts. Albert Einstein was a rotten speller in both German and English and history is littered with dyslexics who became very influential. With tonal languages it can get even funnier. Example: truck driver arrives to deliver his load. It can come out sounding “I am about to give birth”. Aspro (talk) 20:08, 12 August 2017 (UTC)

Ah yes, the Wide Berth of a Nation. :-) StuRat (talk) 20:37, 12 August 2017 (UTC)

What's called tone in tonal languages is not the same as the musical pitch of notes on a tuned instrument; it's about contour. We have this in English, but use it on a sentencial level, with normal declarations having a falling intonation, questions a rising intonation: "The book he wants is _here.." (fact) vs. "The book he wants is ^here?" (question). The word "really" Can have many different intonations:

Really? Really.

Really?!?! (doubt). Really! (exasperation) Really... (sarcasm).

These are all a matter of contour, not pitch. And notice that we do not mistake a woman's statement for a man's question just because her voice is higher pitched. μηδείς (talk) 20:44, 12 August 2017 (UTC)

That reminds me of the time when I was studying Russian at university. One day during a tutorial, the tutor was asking us to translate English sentences into Russian, viva voce. The sentence I was given was "One day I would like to marry and have a couple of children". I said whatever rubbish I said, and both the tutor and a fellow student who was a native Ukrainian speaker and understood far more Russian than I, suddenly erupted into gales of laughter. They explained that I had said the Russian for "One day I would like to give birth to twins". :) But seriously, that was 3 years of pretty intensive Russian study in the late 1970s-early 80s, followed by only very sporadic use of the language thereafter (including having never been to Russia; although I did marry into a Russian-speaking family). To this day my Russian pronunciation is still fine, but I have lost a lot of vocabulary, and I never really did get verbs of motion (mainly because we were warned before we started learning them that they were difficult and some learners never understand them, so as a dutiful student I complied, which is a pity because in most ways I rebel and do the thing I am not expected to do). -- Jack of Oz ^{[pleasantries]} 20:36, 12 August 2017 (UTC)

@ Jack of Oz. As you spent so much time in learning this language why waist all that that effort. You might not know it but that there is a web-site called Википедия whom might welcome your input and thus you can improve your vocabulary. But be warned and take it from me, this is part of a org that insists that one follows unfathomable policies about what images and references one can use. No idea how this world wide international organization still exists (they don't pay their contributors anything). Yet, give it a try ;¬ ) Aspro (talk) 22:49, 12 August 2017 (UTC)

Ну, спасибо ... я думаю ...  :) -- Jack of Oz ^{[pleasantries]}

спасибо Aspro (talk) 01:55, 13 August 2017 (UTC)

Dmcq may find Mango Languages, a service available at my public library and may be available in his/hers, and HelloTalk, a chat app for Apple products, to learn new languages. Mango Languages may not be very useful, because it has preset sentences that require memorization and repetition. But HelloTalk may be more useful, because it is designed as a language-learning social app. The app will ask Dmcq to create a profile and set up a native language and learning language. If he/she wishes to learn Chinese, then s/he may speak with a person from China who is trying to learn English. 50.4.236.254 (talk) 22:10, 12 August 2017 (UTC)

I once worked with someone from a European country who was stationed in the US for a year. As the end of the year approached, he said he was "starting to" forget some of his native language. It all came back once he went back home and was re-immersed in it. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:14, 12 August 2017 (UTC)

• @Dmcq: I found the Spanish returned with immersion. I wasn't "back in the home country", but I was working two or three shifts a week with back-of-the-house bi- or tri-lingual Spanish-speakers who were using Spanish as a lingua franca, and I told them to treat me as an equal and include me in their non-anglosphere. I also befriended several Mexican families, was proposed a marriage of convenience, and lived with Mexicans for about 6 months which was when the dreaming in Spanish and hesitating in English began. If you want to recover the Chinese, get a basic primer and some roommates who speak your previous dialect, or at least socialize with them heavily, and exclude English entirely from dialog. Any using English will cripple your attempt. μηδείς (talk) 20:22, 12 August 2017 (UTC)

What do you mean by "crippling your attempt"? I learned Spanish in an Anglophone environment, and I could read, write, speak, and listen at the elementary level in Spanish. Also, it seems unrealistic that English would be forbidden. If Chinese is only used with the roommates, then the Chinese-speaking roommates may start feeling worried that their own English is not improving. I don't think living with roommates is a good option. Living in China may be better, but Dmcq may need a job to pay the bills and feed himself/herself. 50.4.236.254 (talk) 20:41, 12 August 2017 (UTC)

Non speako trollo. If you can bear to hear the truth you’ve spoken

Twisted by knaves to make a trap for fools....

--Rudyard Crippling

μηδείς (talk) 21:04, 12 August 2017 (UTC)

@ User talk:50.4.236.254) Think what μηδείς was alluding to, was that by not talking in one's mother language at all, it removes the temptation to translate what one has heard into ones mother's tongue of what has been said and then have to converts ones reply back into the language one is attempting to learn. Fluency is quicker to come, by the processes of total immersion. Aspro (talk) 21:36, 12 August 2017 (UTC)

I specifically addressed Dmcq's wondering whether he could "recall" the Chinese of his youth, not learn a new language de novo by taking classes. Fitty's response was simple contrarianism. I did not learn Spanish by taking classes, although I did buy the book on verbs (to better master the spoken preterite), did have an explicit knowledge of French, and did buy a dictionary. That lead to some laughs when I used highfalutin terms like vecindario for neighborhood when barrio was the informal standard. I asked the super of a building I wanted to move into in a Dominican area about the "vecindario", with the answer that "We cannot afford the luxury of vecindarios around here, we have only barrios. Perhaps your mercy should consider a skyscraper downtown?" (This was said jokingly, and I never used the term in speech again.) μηδείς (talk) 22:08, 12 August 2017 (UTC)

Yes, I know immersion helps with language fluency. Speaking like a native is a different matter. But Medeis also suggested that one could get roommates and only speak the roommates' language. I don't think this is a practical suggestion, because the roommates in an Anglophone environment may want to practice more English. One way is to tutor each other. The Chinese native speaker teaches conversational Chinese, and the English speaker teaches English. 50.4.236.254 (talk) 21:58, 12 August 2017 (UTC)

@Aspro: Yes, the OP's teacher's comment seems overblown, but I doubt I was actively using any Spanish at five after six months of pure English. Of course, my parents spoke English at home, not the language that was to be "lost". I know that I also lost my strong Southern accent very fast at that time, because I did not get picked on for it at school.

I wish I could remember some of the terms I hesitated with in English at this time. I 'remember' that they were nouns, but this was three decades ago, and it may very well have been idiomatic expressions. I also had more difficulty when the French and Spanish conflicted, such as the lack of a spoken preterite in French, while Spanish makes huge use of the preterite/imperfect contrast, such as the past forms supe/sabia que (preterite/imperfect) which mean "I knew", but specifically I discovered that vs. I was aware that. I also often "made up" pseudospanish, like asking Donde esta la fontana? (which was understood, but responded to with Hay una fuente aqui) by assuming that French fontaine had a direct cognate, but Spanish uses fuente from Latin fons with no additional suffix. μηδείς (talk) 20:22, 12 August 2017 (UTC)

Uhmm. Now having some hours to think about it, I did have problems with nouns when they applied to parts of the human body and bodily functions to a greater extent than with verbs and adjectives etc. which described those functions. Some words where OK in the school-yard but not OK at home.... and beyond. Which was a problem, since in one language some were OK yet, in other they where considered not OK which lead to adults to sometimes ask has the cat got your tongue? when I was not sure of the polite explanation in that language. But I can't remember any problems with very common nouns. You can bet though, I made up for that deficiency when I became a teenager and was never lost for something to say. Even, if I had to concatenate Latin, Greek and French into something that sounded impressive because I couldn’t think of anything better. Which might be the same reason μηδείς resorted to pseudospanish. The most important thing is to be able to communicate rather than be grammatically perfect – like wot I is now! Anyway the OP seems to have his question answered now. Aspro (talk) 00:16, 13 August 2017 (UTC)

@OP, while personal anecdotes may be interesting, they are no substitute for scientific study. This phenomenon has been studied and there are plenty of references available. The Psycholinguistics pioneer Wallace Lambert devoted his entire career to topics such as this. He called it "subtractive bilingualism" and if I recall correctly, "Bilingualism and language acquisition" is a good read. The book First Language Attrition (Seliger & Vago, editors) is also a good read and contains chapters that deal directly with your question. I can recommend others if you are interested in reading for yourself what the experts have to say.--William Thweatt ^TalkContribs 22:57, 12 August 2017 (UTC)

You're the only person who has answered the actual question instead of commenting on the personal anecdote in the OP with more personal anecdotes. This makes me happy. 50.4.236.254 (talk) 23:09, 12 August 2017 (UTC)

Welcome back, User:Russell.mo. Thanks for the smiley. I remembered the Dublin IP address, but the "makes me happy meme" is strong with you. Here's a discussion of your antics a while back. μηδείς (talk) 04:29, 13 August 2017 (UTC)

Sorry, but I don't know who in the world is User: Russell.mo. Next time, please ask for a CheckUser report. Also, I have read your discussions on the Reference Desk Talk Pages, and you repeatedly misidentify editors. 50.4.236.254 (talk) 04:37, 13 August 2017 (UTC)

Well since you now have had your question answered, perhaps you could tell us how fast one can lose a language? Dmcq (talk) 09:40, 13 August 2017 (UTC)

I was referring to the sources. William Thweatt provides me the sources, which seem interesting and may lead me to the answer, 50.4.236.254 (talk) 11:05, 13 August 2017 (UTC)

Well since you don't actually have an answer yet, how about expanding on the question. Why do you want to know this or what will it do for you? Dmcq (talk) 12:25, 13 August 2017 (UTC)

Because learning new stuff is cool. Knowing the right terminology to search for is helpful. 50.4.236.254 (talk) 16:45, 13 August 2017 (UTC)

That's a bit of a non-answer. This would just be another random fact rather than anything cool. I don't see it entitles you to any extent whatsoever to start complaining about people not giving you a reference to a scholarly work. If you had some decent reason it would enable people to tailor an answer, for instance a question about what isthe height of all the trees in a field with a reason, oh it's cool to know doesn't exactly excite. A reason like I want to know if any could fall on the house would give an entirely different answer. Another saying one is a botanist and are seeing how high beech trees grow would give another again. Dmcq (talk) 20:18, 13 August 2017 (UTC)

In Britain, amongst younger speakers, there is frequently rising intonation at the end of a sentence even when a question is not being asked. I believe this spread from the United States. 82.14.24.95 (talk) 14:53, 13 August 2017 (UTC)

You must be referring to high rising terminal. The article says British people blame the youngsters' habit on watching too much Australian TV. 50.4.236.254 (talk) 16:45, 13 August 2017 (UTC)

High rising terminal is also a feature of Canadians' and New Zealanders' speech. Akld guy (talk) 21:56, 13 August 2017 (UTC)

I saw a horrible scene in the US. A Caucasian man was the adoptive father of a Chinese girl of perhaps 5 years. In a store, she was pointing to things like newspapers and umbrellas and saying what seemed to be the Chinese words for them. He scolded her for daring to speak Chinese. Some adoptive parents take the other view and take their adopted Asian children to weekly classes in the culture and language of their birth nation. Edison (talk) 02:54, 14 August 2017 (UTC)

Mottaphobia

(Inspired by the arachnophobia question above) A few questions about mottaphobia, to help me shed some light on this condition: (1) Does it tend to run in families? (2) Does it usually occur as a generalized phobia (fear of all butterflies and moths), or as a fear of 1 or more particular species thereof -- and if the latter, which species are the most likely to trigger this response? (Speaking for me personally, I'm perfectly OK with most butterfly species, but swallowtail butterflies totally creep me out!) And (3): How much comorbidity is there with other anxiety disorders (particularly with other animal phobias)? 2601:646:8E01:7E0B:21B1:8CA4:6F9F:6132 (talk) 08:41, 12 August 2017 (UTC)

I wonder of the trailing wing parts of a swallowtail butterfly such as a Protographium marcellus remind you of the trailing legs of a wasp in flight: [27]. That might cause the reaction, especially if you've been stung. StuRat (talk) 13:03, 12 August 2017 (UTC)

I think it has to do with their large size (up to 8 inches or more!) more than anything else (although their shape and coloration does play a reinforcing role) -- their juveniles don't scare me as long as they're less than 4 inches or so in size. So, should I take this as evidence that swallowtails are more likely to cause this reaction than most other species? 2601:646:8E01:7E0B:21B1:8CA4:6F9F:6132 (talk) 05:05, 13 August 2017 (UTC)

You do realize that a juvenile butterfly is a caterpillar? The butterfly is the last instar of the organism, it does not molt or grow after appearing from the chrysalis: there are no little butterflies growing into bigger butterflies; it is an impossibility. μηδείς (talk) 15:32, 13 August 2017 (UTC)

No, I didn't know that! So what explains the wide variation in size, from 3-4 inches to 8 or more? 2601:646:8E01:7E0B:21B1:8CA4:6F9F:6132 (talk) 04:51, 14 August 2017 (UTC)

Different species, different sizes. Size variation within the same species would depend on how well the catterpillar ate. Roger (Dodger67) (talk) 09:11, 14 August 2017 (UTC)

Eye color and light absorption

Eye_color#Brown says that due to high melanin concentration in the iris this color absorbs both shorter and longer wavelengths. Does it mean that brown and dark brown eyes are less protected against direct sunlight, compared to other eye colors, similar to sun glasses and UV filter? I read that in case of hair color the black absorps absorbs more heat than blonde so that the former becomes warmer after 5 minutes of direct sunlight. Brandmeister^talk 21:43, 12 August 2017 (UTC)

No, not if you mean light hitting the retina, because the eye color is not in the path of light that hits the cornea. That's a bit like saying the paint color on your car affects how much light makes it through the windshield (although in that case at least some light is reflected off the paint into the windows, unlike with eyes).

Now, if you are asking if the pigment itself is more likely to be damaged by UV light, that's possible. I don't know the answer to that. StuRat (talk) 21:45, 12 August 2017 (UTC)

• You have the reasoning backwards. Like pale skin, blue eyes are more sensitive to sunlight. The dark iris protects the sensitive retina by keeping out more light. μηδείς (talk) 02:29, 13 August 2017 (UTC)
  • Yep, that makes sense. But I also wonder whether due to absorption of both shorter and longer wavelengths dark eyes have somewhat better vision than other colors? Brandmeister^talk 07:39, 13 August 2017 (UTC)
• Does a significant amount of light reach the retina after passing through the iris? It's the light passing through the pupil that focuses on the retina. Dbfirs 06:14, 13 August 2017 (UTC)

That's the whole reason the iris is pigmented; to allow a variable aperture, the closure of which blocks more light. The pigment does the blocking. If brown irises were to let only 1% of light to pass, while blue irises allowed 2% (I'm making those numbers up) then people with blue irises would still be getting twice the amount of extra light. Studies vary in their conclusions, but the overall picture is that blue-eyed people get much more UV damage overall. Unexpectedly, one Y2K study did show brown-eyed people got more cataracts, but the explanations offered for this are speculative. μηδείς (talk) 15:55, 13 August 2017 (UTC)

And just to clarify, it is the lens, not the iris which does the focusing. The purpose of the iris is to regulate light incidence on the retina, not to focus it. μηδείς (talk) 01:22, 14 August 2017 (UTC)

August 13

Nicotine addiction

request for medical advice, user wishes to take a drug and wants to know how it will affect him
The following discussion has been closed. Please do not modify it.
I'm curious what nicotine addiction feels like so I plan on doing e-cigarette's. I'm fine with the crash I'll experience for a few weeks after quitting but I'm wondering if it'll be like low-level craving it for years/rest of my life? I don't want to wake up everyday forever thinking damn I wish I had some nicotine. 2.102.184.47 (talk) 03:44, 13 August 2017 (UTC) Please read the instructions at the top of the page, we cannot make medical predictions or speculate on the future. μηδείς (talk) 04:05, 13 August 2017 (UTC) I think dismissing this is an unjustifiable cop-out. Nicotine is not a prescribed medication, and sources on the rapid onset of addiction are available: [28] [29] [30] Note these sources all agree that one can become addicted within two days, though it may not happen that fast. As in Charlottesville, there is more harm to be done by suppressing discussion than by permitting it. Wnt (talk) 12:05, 13 August 2017 (UTC) The FDA has regulated all nicotine products since August 2016 https://www.fda.gov/tobaccoproducts/labeling/rulesregulationsguidance/ucm394909.htm. This is a request for personal advice on how the use of a drug will affect the individual, a classic no-no. μηδείς (talk) 15:24, 13 August 2017 (UTC) I tried smoking as a youth, but it just made my heart pound, so I could not achieve the habit. Alcohol and caffeine worked better. It might be genetics. Edison (talk) 02:44, 14 August 2017 (UTC)

identify an insect

Triangular shaped bug about 5-7 millimetres long. I think it is initially translucent, then green and finally brown (not sure though). Dozens of this insect are present on the stalks of a bean plant. It is not feeding on the leaves, but probably on the stalk. Not found on nearby plants until the bean stack was cut down / pruned. Ants seem to interacting with it a lot (I think). Google reverse image search wasn't helpful.

unknown insect about 5-7 mm long found on bean plant.

— Preceding unsigned comment added by Cplusplusboy (talk • contribs) 07:04, 13 August 2017 (UTC)

These look like larvae of some species of Cicadellidae or leafhoppers, sap sucking insects that probably produce honeydew which accounts for the opportunistic (or farming) ants. There are very many species and some specialist sources will probably be required to establish the exact indentification. Compare with this image http://www.ozanimals.com/Insect/Leafhopper-larvae/Cicadllidae%20family/spp2.html. Richard Avery (talk) 10:18, 13 August 2017 (UTC)

The thorn shape reminds me of a treehopper - for example, [31] reviews that this shape is pretty representative, and involves a much modified pronotum... the setae do make it seem more like a nymph, though early treehopper stages apparently don't have the thorn shape. this photo of Acanthuchus trispinifer looks similar but not identical to me. Our resources, including Wikispecies, seem almost entirely deficient on any kind of Terentiini other than this species. Wnt (talk) 11:56, 13 August 2017 (UTC)

The pictures in the landcareresearch.co.nz link are the ones (unless this shape and colour are commonly found in other species). The green photos with the pyramid shaped head and curved tail I posted are nymphs and the brown ones not posted here is the adult tri-horned treehopper as per the website. Thanks Cplusplusboy (talk) 16:37, 13 August 2017 (UTC)

Do the ants actively protect these from predators? I want to know whether I can get these pests to get eaten by predators if I get rid of the ants. The ants seem to have made a colony under the soil very close to the plant on which these insects were found Cplusplusboy (talk) 16:46, 13 August 2017 (UTC)

Pressure during gravitational collapse

How much pressure approximately (say, in GPa) is generated by gravitational compression during gravitational collapse of a star (also in cases of black holes)? Thanks.--212.180.235.46 (talk) 14:46, 13 August 2017 (UTC)

• I don't know, but add it to Orders of magnitude (pressure) when you find out. Abductive (reasoning) 19:50, 13 August 2017 (UTC)

If I haven't lost a decimal place, I believe the sun's core is roughly 34 million GPa, which should give a representative idea of the pressures involved. Dragons flight (talk) 10:44, 14 August 2017 (UTC)

Fat

What is the maximum dietary fat intake per day and over what time period to cause rabbit starvation? Does the type of fat make any difference (animal vs plant)? The article is vague on the specifics. Thanks — Preceding unsigned comment added by 134.213.208.187 (talk) 18:56, 13 August 2017 (UTC)

Rabbit starvation occurs when there is excessive protein and too little fat in the body.[32] This study suggests that there is no difference between lentil-based protein and animal-based protein on nitrogen absorption and thus hints that the lentil-based protein can be used to feed moderately malnourished children.[33] Dr. Michael Greger reports that eating a high-fat, high-protein animal-based diet faces a much higher mortality rate than eating a high-fat, high-protein vegetable-based diet here and the Standard American Diet. SSS (talk) 19:35, 13 August 2017 (UTC)

Looking at Vegetarian nutrition, I see no problems with plant-based fats (...Yummmm. Avocados...). Vegitarians and vegans have to take some extra care to avoid nutrient deficiencies, but millions and millions of people do it and live healthy lives without eating animals. Note: I am not a vegetarian; I am just reporting what the science says. --Guy Macon (talk) 21:36, 13 August 2017 (UTC)

Presently the US government suggests that a person who needs 2000 kcal per day consume no more than 65 grams of fat a day and of those that no more than 20 grams be saturated fat. If the total energy need is 2500 kcal then the corresponding numbers are 80 g fat and 25 g saturated fat. See also [34]. The nanny state worries about us consuming saturated fat, sugar, and caffeine.Edison (talk) 02:40, 14 August 2017 (UTC)

Tunnel, sea

Are tunnels crossing the sea, like the euro tunnel, a tube over the sea bed or are they dig under the ground like a subway? — Preceding unsigned comment added by 31.4.149.201 (talk) 22:22, 13 August 2017 (UTC)

The Channel Tunnel was dug through the sea bed.. You can see a cross-sectional diagram at that article. Rojomoke (talk) 23:28, 13 August 2017 (UTC)

I think in general, laying a tube over the sea bed but deep under water has the problematic aspect that a rupture would make immense quantities of water enter at once. A tube beneath the sea bed can be dug like any tunnel beneath the water table (including tunnels on "land") - to be sure, it is immersed, but the permeability of the rock determines how rapidly water can enter. Wnt (talk) 23:44, 13 August 2017 (UTC)

Both techniques are possible. As noted, the Channel Tunnel (or Eurotunnel) was bored below the seabed, but on the other hand, the Transbay Tube is indeed "a tube over the sea bed". However, note that while both are under arms of the sea, the English Channel is a good deal deeper than San Francisco Bay.

By the way, note that subways are not always "dug under the ground". Another common technique is to dug them into the ground as open trenches which are then then covered over. See Tunnel#Cut-and-cover. --69.159.60.147 (talk) 06:19, 14 August 2017 (UTC)

That article links to Undersea tunnel but it doesn't really discuss construction methods that much. However it does link to our article on the Immersed tube tunnel. From there, you'll find a link to the article on the theoretical Submerged floating tunnel. Nil Einne (talk) 07:20, 14 August 2017 (UTC)

BTW those articles claim without sources that Marmaray is the deepest immersed tube tunnel in the world, and per our article its deepest point is around 60m. Busan–Geoje Fixed Link is said to be the deepest road immersed tube tunnel and our article suggests it could be the second deepest, being 48m at its deepest point. By comparison, our article says the Channel Tunnel is 115m below the sea level at its deepest point although it's also 75m below the sea bed. Going back to the earlier articles, we find Eiksund Tunnel which is said to be the deepest overall and is 287m at its deepest point. However it seems Rogfast is probably going to be 390m at its deepest point. Nil Einne (talk) 07:32, 14 August 2017 (UTC)

• Øresund Bridge is another to look at. 3.5km of buried tube tunnel. Andy Dingley (talk) 09:29, 14 August 2017 (UTC)

DIY crappy chokes for VGA cables?

The VGA cables I have don't have chokes on and I think there is some interference between them or them and something else. Is there something I can use to make a choke that I can apply to the cable? I have a few ferrite toroids but I can't get them around the cable without cutting the cable first (not doing that, obviously). I have some strips of thin steel I could wrap around and maybe magnetise first if that would make a difference. --145.255.246.8 (talk) 23:26, 13 August 2017 (UTC)

A ferrite choke, scored with a file, snappped in half and then superglued back together is still a reasonably efficient choke. There are also ferrite rings made in two pieces, ground smooth on the mating surfaces, and held in a snap-lock plastic housing. You can often find these on old cables: monitor or keyboard. I habitually recycle these when scrapping old keyboards, they're often useful for ad hoc suppression tasks. Andy Dingley (talk) 09:26, 14 August 2017 (UTC)

https://www.amazon.com/dp/B01MRIKIJX/ref=asc_df_B01MRIKIJX5121726 Also see: http://palomar-engineers.com/ferrite-products/snap-on-split-beads --Guy Macon (talk) 09:31, 14 August 2017 (UTC)

Industrial uses of seawater

Here in the non-coastal US, we always have enough water for drinking and other non-agricultural uses (the only significant effect of droughts is that farmers who can't irrigate may lose their crops), and when non-potable water is needed for ordinary industrial purposes (firefighting, power-washing, dust suppression, etc.), we routinely use water from the mains or from a river if it's available. Can seawater generally be used for similar purposes? Geography of Singapore notes that their freshwater needs surpass what they get from rainfall, and I'm left wondering if they're able to use seawater in such contexts (i.e. if they couldn't, they'd have to import far more water than they do now), or if for some reason it's impossible and they have to import water for industrial purposes as well. Nyttend (talk) 23:47, 13 August 2017 (UTC)

PS, I'm familiar with fireboats; I'm wondering if it's practical to set up water mains for seawater for the sake of firefighting that's not near the shoreline. Given Singapore's numerous high-rises, I doubt they'd want to rely on tanker engines, and obviously they can't use long fire-hoses to pump water for non-shoreline fires. Nyttend (talk) 23:50, 13 August 2017 (UTC)

Bad idea, contaminating all the waste water with salt (if you recycle waste water for drinking etc). Also, what proportion of the ciy's water usage is fire fighting - not much i'd guess rather negating my first point. Greglocock (talk) 01:57, 14 August 2017 (UTC)

It suggested to use seawater for cooling in Singapore [35]. I suspect it happens in practice but am lazy to search for sure but it definitely happens elsewhere although this does require careful consideration of the cooling system design, and also leads to concerns over the local marine environmental effects of tie discharge [36] [37] [38] [39]. A particularly common user is power plants but again there's a lot of controversy over the effects of such practices on the local marine enviroment, especially with once through systems [40] [41] [42] [43]. Nil Einne (talk) 07:14, 14 August 2017 (UTC)

[44] discusses using sea water in mining operations but although it does mention the possibility of using it straight, all the examples cited seem to involve some desalination. Nil Einne (talk) 07:35, 14 August 2017 (UTC)

Salt water is not very gentle on whatever you put it into (pipes, etc.). Also, in some of the example applications you gave, the water will then evaporate and leave the salt behind, which is usually undesirable. Reclaimed water systems are what is generally used to produce non-potable water and reduce water usage. --47.138.161.183 (talk) 08:10, 14 August 2017 (UTC)

Salt doesn't tend to come out of solution until the seawater is quite concentrated. At high temperatures, the bigger problem is sulphates, as these form a hard scale that's hard to shift. Provided that brine isn't concentrated more than three times, and doesn't exceed 60ºC, it's not a big problem (see Evaporator). Andy Dingley (talk) 09:44, 14 August 2017 (UTC)

August 14

Trying to find a video footage of Albert Einstein

A few years ago, in some TV scientific program, a short & rare footage was shown, with Einstein. The impression made by it is immense - 'looking' at you, surveying you from top to bottom, as if you were completely transparent. Chilling. Unforgetable. I'll be very glad to hear about this movie and how to get it. I need it also for psychophysical research. בנצי (talk) 08:08, 14 August 2017 (UTC)

Is this real?

https://www.youtube.com/watch?v=-Cto1DXXHAc for something as easy to test as this, I'm sure professional labcoats have done it 1,000,000,000 times already. Is it real? I've never even heard of any alien looking life form. Money is tight (talk) 11:09, 14 August 2017 (UTC)