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March 8

Vinegar and breathalyser 2

Follow up question was hijacked and taken on tangent: what would vinegar do to a breathalyser test result? There is no legal advice being sought. There is a specific chemical process taking place and the question is what would happen if there was significant vinegar consumption 3 big pickles prior to test? Thanks 66.87.80.255 (talk) 02:39, 8 March 2015 (UTC)

It would do nothing. Breathalyzers work by oxidizing ethanol to acetic acid, which is the main ingredient in vinegar. A breathalyzer is basically a pocket galvanic cell that generates a small voltage by a redox reaction. When the ethanol --> acetic acid oxidation causes a reduction of oxygen --> water. Since acetic acid is basically already oxidized ethanol, it can't be further oxidized, and the vinegar on your breath has no effect. --Jayron32 04:57, 8 March 2015 (UTC)

• The question really is how much alcohol is there in vinegar. True diluted acetic acid is generally sold as "imitation vinegar"; the rest is basically spoiled wine or apparently in some cases spoiled beer, etc. There's one site being quoted where the guy claims to have found some paper that found brands of balsamic vinegar with up to 2% alcohol, but I have no idea if that's legit or not; in any case that's an outlier. A lot of it is subjective - when do you open a bottle of wine and say "pee-you, that's vinegar"? The regulatory requirement is vinegar being 4% acetic acid, and to work well for some applications apparently it has to be 5%, which it almost always is; this limits the amount of alcohol present to some degree. Note though that drinking even spoiled wine and failing a breathalyzer might not be a reliable defense! Wnt (talk) 12:59, 8 March 2015 (UTC)

Cosmological distance

When cosmologists are recording distances of certain objects which have been determined are in fact moving away from us due to expansion, can they factor exactly how far the object is at present? If yes, which distance is actually used for the record? Or does it depend on what is being researched?66.87.80.255 (talk) 03:46, 8 March 2015 (UTC)

I don't think so. For one thing, there is no universal "present" time. When they say that it is a certain distance from us, that is based on the light reaching us now. Bubba73 04:10, 8 March 2015 (UTC)

but one of the few facts we know about that object is that it is not now where we are seeing it. So shouldn't we say we know it's specifically not there for the record?66.87.80.255 (talk) 04:23, 8 March 2015 (UTC)

Bubba73 is wrong—distances reported in the popular press are usually comoving distances, which are distances extrapolated to the current cosmological time, assuming current cosmological models are correct. "Official" distances are normally given as redshifts, since that's what's actually measured. See Distance measures (cosmology). -- BenRG (talk) 04:36, 8 March 2015 (UTC)

Thank you for correcting that. Bubba73 04:52, 8 March 2015 (UTC)

Most of the time it is most useful to specify where an object appears to be, since that is the information of greatest utility to people with telescopes. We do however have numerous concepts for kinds of astronomical distances. See for example distance measures (cosmology). The main ones are proper distance, comoving distance, and light travel distance. These are related and generally calculable from one another provided basic information is available, though the main examples all tend to deal with the apparent properties of the object. The implied future of the object is generally of less interest. Given velocity and position one can roughly predict where an object X light years away would presumably be X years in its future, but since we can't observe that future or test those predictions (except for very small time durations), such predictions generally aren't of much direct interest. However, astronomers do know very well that what they observe today reflects the universe as it was rather than as it is. Dragons flight (talk) 04:45, 8 March 2015 (UTC)

so is there an instance where the object is moving toward us faster than others or counteracting the expansion where it would be in that same spot "at present"?66.87.80.255 (talk) 05:00, 8 March 2015 (UTC)

The Andromeda Galaxy is moving towards us. --TammyMoet (talk) 09:53, 8 March 2015 (UTC)

what I meant was 2 objects that are the same current distance away that are moving away due to expansion but are moving away at different speeds.66.87.80.255 (talk) 14:12, 8 March 2015 (UTC)

Different speeds compared with what? The speed that other objects are receding? That's the case all over the place. As I recall, the farther away objects are receding faster than the closer objects (or to put it another way, we are receding faster from those farther objects). ←Baseball Bugs carrots→ 17:50, 8 March 2015 (UTC)

yes but you misread the question i said the same current distance but different speeds.66.87.82.116 (talk) 23:01, 8 March 2015 (UTC)

Building Mars on Earth

During the video embedded in this article, there seems to be a woman who is standing next to a Mars rover on what appears to be a Martian landscape. Have researchers at JPL, or anywhere else, been modeling the Martian landscape at a 1:1 scale? Dismas| 06:38, 8 March 2015 (UTC)

It's probably easier to use Earth deserts that already resemble the Mars landscape. (Sometimes the only way you can tell the difference is if the sky is blue or red.) StuRat (talk) 14:18, 8 March 2015 (UTC)

The atacama desert resembles mars the most. — Preceding unsigned comment added by Joey13952 alternate account (talk • contribs) 17:38, 8 March 2015 (UTC)

Nah, the Atacama is just very very dry. Appearance wise there's this island in Northern Canada, I think that is closest in appearance to Mars and the folks at NASA use it from time to time. Sir William Matthew Flinders Petrie | 17 Adar 5775 17:43, 8 March 2015 (UTC)

You are presumably referring to the Mars Society's Flashline Mars Arctic Research Station on Devon Island, though as Wnt points out, Dismas was asking about a different kind of modeling. -- ToE 23:46, 8 March 2015 (UTC)

That's the one! Sir William Matthew Flinders Petrie | 18 Adar 5775 00:17, 9 March 2015 (UTC)

Acchcch, come on people, at least clicka the link before you answer! The link shows a believable simulation of the Martian surface generated by computer, and gives the strong impression they used real rover images to make it. The simulation may be intrinsically no different than any computer game in 3D, but to get the positions for all the rock faces I don't know if they used parallax between many images at known displacements of the camera or had some kind of nifty laser rangefinding or something available (someone could quickly look that up, I'm just being lazy; I doubt it). I don't know how accurate they're trying to make the simulation either, but again, guessing, I'd guess "pretty damn". Anyway, consider yourselves trouted. Wnt (talk) 21:40, 8 March 2015 (UTC)

So the quick shot of the woman standing next to the rover at roughly 28 seconds in is just green screening or some similar special effect? The shot is too short for me to really tell if there is green screening going on or if she's at some real/physical test location. Dismas| 00:10, 9 March 2015 (UTC)

Nope, that appears to be a mock-up they built in Pasadena. I was going to mention it last night (and answer your question in doing so) after watching the vid but was either too drunk or too tired to post. Probably both. Sir William Matthew Flinders Petrie | 18 Adar 5775 00:17, 9 March 2015 (UTC)

It's clearly a real location; I don't know where it is, but I know that there are artificial lunar/martian landscapes used for rover testing, such as the "roverscape" at Ames Research Center. -- BenRG (talk) 00:32, 9 March 2015 (UTC)

It says Jet Propulsion Laboratory, Pasadena, CA between 0:12 and 0:14 in the vIdeo. I didn't notice the JPL bit the first go around, but that's where it is, whatever it's called. Sir William Matthew Flinders Petrie | 18 Adar 5775 00:42, 9 March 2015 (UTC)

It's the JPL MarsYard III (Google Maps, video panorama). -- BenRG (talk) 05:23, 9 March 2015 (UTC)

Sorry, I missed the shot at :28 because, well, it doesn't really look much like Mars. I mean, I've never seen photos of boulders sitting on top of a smooth surface like that; it just looked like a rover test course to me. Wnt (talk) 12:32, 9 March 2015 (UTC)

The Curiosity rover has a pair of "mast cameras" placed to generate stereo pairs, just like human binocular vision. From those, it's fairly trivial to extract reasonably accurate distance information to everything in the field of view - and as the rover moves around, you can assemble three-dimensional models for everything it's ever seen (and transmitted back to earth) through those cameras. The 3D models would be partial because the back sides of the rocks would never have been seen by the camera - I'd expect NASA to 'fill in' those details with similar-looking synthetic detail - which they probably mark somehow so that the users of the system know what's "ground truth" and what's merely in-fill. Once you have a 3D model, with color, texture, and lighting information, it's not difficult to write software to display that in a head-mounted display - it would be MUCH easier than writing a video-game. This is something that any competent graphics engineer could put together in a month...truly not "rocket science"...and these days, hardly an engineering challenge at all. SteveBaker (talk) 18:40, 9 March 2015 (UTC)

Thank you, all, for your responses! Dismas| 14:11, 12 March 2015 (UTC)

The limits of mind

Did been a limit of the possibilities of mind?--85.140.136.25 (talk) 10:49, 8 March 2015 (UTC)

If the human mind is always been Goodness, so is it an absolute the mind of Lord God?--83.237.216.191 (talk) 11:53, 8 March 2015 (UTC)

please ask scientific questions, and in English. --OuroborosCobra (talk) 12:21, 8 March 2015 (UTC)

The natural nature of mind is it been absolute?--83.237.216.191 (talk) 13:11, 8 March 2015 (UTC)

You appear to be talking through google translate. It is not possible for people to understand what you are asking exactly. Beyond the rather basic fact that the human brain must have limits on its cognitive capacity, maybe you are trying to see if there are limits to what we understand. This may also be asked based on a confusion between limits on a person's own cognition and limits on the body of knowledge in general (the former not limiting the latter because of the nature of specialisation). If you try to read that through google translate, it will not be possible to follow what I am saying. Second Quantization (talk)

Google translate doesn't capitalize the word "Goodness" in the middle of a sentence. Nor is there any term in Russian that would translate as "did is been?" μηδείς (talk) 21:35, 9 March 2015 (UTC)

Is it in applied sense the (physiological) properties of the (neurons) neural net, as also as (physiological) properties of the neuron been absolute?--83.237.204.27 (talk) 14:20, 8 March 2015 (UTC)

For what the atomic (molecular) particle is the mostly similar been neuron?--83.237.204.27 (talk) 14:39, 8 March 2015 (UTC)

I suggest you post here in your native language and then one of us who speaks it can post a more meaningful translation. --TammyMoet (talk) 19:52, 8 March 2015 (UTC)

The storage capacity of the human brain has been estimated in a bunch of different ways - with wildly differing answers given - but there is, undoubtedly, a limit. In our Orders_of_magnitude_(data) article, the number 1.2 terabytes is offered...but this Scientific American article suggests 2.5 petabytes...which is a couple of thousand times greater. So the precise number isn't known. However, it's safe to say that nobody, no matter how smart could possibly memorize more than 7,500,000,000,000 digits of pi (for example). You can buy hard disk drives for your computer that are a couple of terabytes - so our memory capacity is between one and two thousand hard drives worth. So there is one hard limit.

Another hard limit is on processing speeds - we know that a neuron can't fire much faster than around 200 times per second - so even with all 100 billion of them working at once, we can't perform more than 20 trillion basic calculations per second. That's comparable to the graphics chip in a decent modern computer.

Another measure is this - in which they claim that the human brain can recognize an image in about 13 milliseconds - which is a little faster than a computer can (for example) recognize a face using the algorithms developed by FaceBook - but not much faster.

These are all theoretical maximums - the likely number of digits of pi that could be memorized (assuming you didn't memorize anything else!) will for sure be drastically smaller than that...so treat these as upper limits.

What these tell us is that the capacity, speed and general throughput of a human brain is very roughly comparable to a high-end desktop computer. That said, where we win is in the 'software' and general architecture of the brain. We store memories in a very compact way, storing concepts rather than pixels, or sound samples. We're able to dynamically reduce the precision with which old memories are stored and automatically erase the ones we don't need anymore. These are all things that computers can't do yet...and the consequences are that we can do things like rapidly recall all of the important details of a 100 year lifespan...a feat which seems to suggest vastly more storage than we really do have, mostly because we're exceedingly clever at how we store things and when (and how) we forget them. SteveBaker (talk) 18:29, 9 March 2015 (UTC)

So, in what is been the difference between a neuron from electron as an elementary physical-molecular particle?--83.237.217.95 (talk) 11:46, 12 March 2015 (UTC)

Do you actually understand the replies that are given to your questions? Your latest post suggests not, and I can see no point in responding if you are unable to demonstrate that your English comprehension skills are better than your writing. AndyTheGrump (talk) 11:52, 12 March 2015 (UTC)

Sorry for my English. I’m interesting in such as, In what is been the physical difference between a neural impulses from the electronic impulses, and could according to the universal Law of conservation of energy a neural impulse was keeping safed in an electronic impulse?--83.237.217.95 (talk) 12:03, 12 March 2015 (UTC)

I’m thinking, that could been done the flash (neurons) neural memory card as a simple flash memory card (SIMM) of electrons.--83.237.217.95 (talk) 12:11, 12 March 2015 (UTC)

In any case, the total between the neuron and the electron is always been a fact that the neuron as the electron could keep safed an information, so the neuron as the electron was always had a physical memory.--83.237.212.25 (talk) 12:37, 12 March 2015 (UTC)

Of course, a biological processes and physical processes could be irreversible, so that the neurons can degrade or mutate, and electrons can also aging.--83.237.212.25 (talk) 13:00, 12 March 2015 (UTC)

The physical state of an elementary particle or biological cell is their physical memory.--83.237.197.231 (talk) 14:09, 12 March 2015 (UTC)

Why did been necrosis of the brain, is it been because the electrons get older?--83.237.223.29 (talk) 15:30, 12 March 2015 (UTC)

Superconductivity of neural system of the brain is always been formed (determined) by speed of the electrical streams (by the speed of electricity) of neural system.--83.237.206.31 (talk) 18:09, 12 March 2015 (UTC)

From my point of vision in this issue all concludes in the value of the electrical bonding (connecting) in biology, physiology, genetics, biochemistry, and so goes on.--83.237.206.31 (talk) 18:26, 12 March 2015 (UTC)

Biochemistry papers

Why do many biochem papers not show the chemical structure diagrams. Only the formula. — Preceding unsigned comment added by 82.132.214.244 (talk) 16:01, 8 March 2015 (UTC)

Which paper(s) or publications are you reading?

Biochemistry (journal), a publication of the American Chemical Society, provides author guidelines with instructions on how to submit chemical structure diagrams, and further stipulates that details for complicated biological macromolecules must be uploaded in digital form to computerized chemical databases operated by partner organizations of the publisher.

Other publications may have different guidelines suitable for a different reading audience.

Nimur (talk) 16:12, 8 March 2015 (UTC)

Biomaterials. — Preceding unsigned comment added by 82.132.214.244 (talk) 16:39, 8 March 2015 (UTC)

If you mean Biomaterials (journal), a publication of Elsevier, here are the author guidelines. There are no guidelines or rules respecting chemical structure diagrams, formulae, or digital database formats for molecular structure. There is, however, a handy buzzkeyword list provided to authors. I could insert a snide commentary about journal quality and the role that economics plays in consolidating scientific writing into the hands of a very small number of private-sector, non-science publishing houses... but I think the guidelines speak for themselves. My advice, though, is pretty simple, and it comes from several years as a professional editor of research publications: read papers that are good, not papers that are published in "respected" journals. After you read a lot of papers, you will learn which journals (and which editorial staffs) have earned your respect. Nimur (talk) 20:59, 8 March 2015 (UTC)

Apparently it's assumed that the reader will know the structure from just the chemical formula or be able to look it up easily. — Preceding unsigned comment added by 82.132.214.244 (talk) 17:00, 8 March 2015 (UTC)

IUPAC rules are supposed to make chemical formulae readily communicable in words. Formulae are often included for new (or newly isolated) compounds, however, because of the possibility of error or misunderstanding. Wnt (talk) 21:43, 8 March 2015 (UTC)

Wind

You are in a field and it is windy. You have two possibilities. 1st: stay in the open, 2nd, enter a tube, which is straight and not perpendicular to the wind. What would be warmer?--Llaanngg (talk) 20:01, 8 March 2015 (UTC)

Is it cloudy in this hypothetical scenario? What is the wind speed? What is the outside air temperature? Is it day or night?

In all seriousness, we don't have enough information to answer the question definitively. Temperatures - and heat loss, which is actually a distinct phenomenon - are affected by many parameters beyond linear airflow. Why do you want to know, and how technical do you wish your answer(s) to be? Nimur (talk) 20:11, 8 March 2015 (UTC)

Just curiosity, to understand it. We could use a wind speed of 5m/s, which is a common air speed in many places, and 15 degrees C, and 45 degrees angle, for the tube. And why does being cloudy/day or night affects the experiment? --Llaanngg (talk) 20:28, 8 March 2015 (UTC)

The sun is a source of heat! A tube will shade you from sunlight. Heat loss through radiation into space is non-negligible! On a clear night, the interior of the tube may lose less heat (to radiation) than an exposed area.

Start by reading about heat conduction, convection, and heat radiation. These are the primary ways that heat flows. Wind is generally described best by convection (though there is thermal conduction by direct contact with the air mass, too). Ultimately, your tube experiment can be reduced to a more generic question: under what conditions does airflow cause so much more heat transfer that we can neglect all other forms of heat loss? The answer can be paraphrased: when the heat lost to flowing air is much greater than heat gained or lost by radiative or conductive transfer. Nimur (talk) 20:39, 8 March 2015 (UTC)

How big a tube? If I'm able to position myself to block much of its area and it's got a substantial length between me and the upwind end, I could probably prevent having much air move in front and behind me. But "much of" and "substantial" are pretty hard to model quantitatively without knowing a lot of specific details of the surfaces, etc. DMacks (talk) 20:37, 8 March 2015 (UTC)

And what is the tube made of? Is it nylon, cloth, concrete, metal, earthwork...? Is it in direct contact with the ground? Under ground? ... A half-buried concrete drainpipe and a metal drainpipe of equal size will transfer heat very differently. If both are exposed to the same conditions - say, a warm sunny day - a metal pipe can become scalding hot, while a concrete pipe can stay very cold. The air temperature in both tubes might be nearly the same.

Using more technical language: what is the thermal coefficient of the tube's material (how quickly does it transfer heat)? And what is its thermal mass (its heat capacity), or how much heat can it store? What is its albedo, or how efficiently does it reflect solar heat?

Nimur (talk) 20:43, 8 March 2015 (UTC)

The wind would be reduced if the pipe is at a 45 degree angle. However, a thick concrete pipe has a significant thermal lag, so that it will get hot later in the day than the air outside, and stay hotter as the air starts to cool. The color of the outside of the pipe also matters, as a black pipe will heat up a lot more than a white one, in sunlight. StuRat (talk) 05:41, 9 March 2015 (UTC)

Scarring

Why is it that most infections don't cause lasting damage and once fully recovered the person is just as healthy as before? Surely an infection anywhere, whether it's the stomach, lungs etc causes scarring and subsequently permanent damage. — Preceding unsigned comment added by 194.66.246.25 (talk) 22:14, 8 March 2015 (UTC)

Why would you think it would? You have evidence that it doesn't, based on all human history. There's little reason to suspect that it would. --Jayron32 00:09, 9 March 2015 (UTC)

Minor injuries, whether caused by injury or disease, can be repaired by replacing the damaged cells. This process happens all the time, when cells naturally die. It's only when too large of an area is damaged at once to use this method that scars are formed to quickly seal the damaged area. Unfortunately, we don't seem to have evolved a way to replace scar tissue with healthy cells later on.

To compare to a scratch on a car, if only the polish is damaged, then just repolishing it repairs it completely. But, if the damage was a tear in the sheet metal, then you might need to patch it with some Bondo, which is never quite as good as it was. StuRat (talk) 05:29, 9 March 2015 (UTC)

• The question is valid. Certain types of tissue, like epithelial tissue regenerate rapidly, while things like cartilage barely regenerate at all. Scarring is caused when the regenerative underlying layers of tissue themselves are damaged. But certain things like the skin and gut are designed to regenerate when not too badly damaged. Some minor scarring can fade over time. Cells are normally inhibited from reproduction when they bound upon other tissue (cancer occurs when this inhibition is lost). If the scar tissue slowly degrades, normal cells bordering it can reproduce and fill in the previously scarred area. That will depend on the age of the person and the size of the scar. μηδείς (talk) 16:14, 9 March 2015 (UTC)

Because evolution have left us with an immune system where most maladies are a trifle. Add to that, good wholesome chlorinated potable water, a balanced diet and a sanitation system to take all the wast products away, we are pretty well bullet proof. Rare (today) infections like Scarlet fever benefit from (our point of view, not the bacteria's ) antibiotic's because that can scare heart-valves and leave lasting psychological damage. --Aspro (talk) 02:00, 10 March 2015 (UTC)

March 9

Does height matter when it comes to air pollution?

Does height matter when it comes to air pollution? I'm wondering whether living and/or working on the top floors of rise buildings would mitigate the effects of air pollution somewhat for polluted areas. If so, how high would it have to be to make a difference? WinterWall (talk) 03:40, 9 March 2015 (UTC)

Removal of pollutants by the building's HVAC system would be far more important. Short Brigade Harvester Boris (talk) 03:42, 9 March 2015 (UTC)

There's no central HVAC system at all, so there's no filtering at all. Just individual per-room AC units (that doesn't filter air at all, just re-circulates indoor air). WinterWall (talk) 05:47, 9 March 2015 (UTC)

It's hard to believe that a high rise would lack a ventilation system entirely. Without one, the air would soon become unbreathable. StuRat (talk) 05:54, 9 March 2015 (UTC)

As hard as it is to believe, central HVAC is an unaffordable luxury for much of the world, much like clean, breathable air. WinterWall (talk) 06:05, 9 March 2015 (UTC)

Yes, but that portion of the world lacks high rise buildings. I can't imagine a society that can afford to build them, but not to ventilate them. BTW, note that I am only talking about the V in HVAC. I can believe that it wouldn't be cost efficient to fully air condition a high rise at certain times of the day or year, when ambient temperatures are high and occupancy rates are low. As for central heating, it may not be necessary in all places. StuRat (talk) 16:44, 9 March 2015 (UTC)

It depends on which pollutants you mean. Some are heavier than air, or are produced at the surface (like horse manure fumes in the olden days), while others are lighter than air (perhaps because they are hot) and/or vented in high smokestacks. StuRat (talk) 05:22, 9 March 2015 (UTC)

I'm concerned about PM2.5 particulates mostly, but PM10 as well. For my purposes, we can ignore the stuff like CO, NOx and greenhouse gases.WinterWall (talk) 05:46, 9 March 2015 (UTC)

Regional air pollution is generally assumed to be well-mixed through the planetary boundary layer, roughly the lowest 200 to 2000 meters of air depending on local conditions. So, in that case being in a high rise wouldn't matter much unless the building were exceptionally tall. The exception would be if the local area around the building were a significant source of air pollution, e.g. heavy industry, freeways, etc. In that case the local pollutants which haven't yet mixed through the air column might make the low levels worse, though in most areas this is not a large effect. Dragons flight (talk) 18:01, 9 March 2015 (UTC)

How were comic books mass produced at the beginning of the 20th century?

I know with the printing press which of course long preceded the beginning of the 20th century, textual pages could be mass produced by setting metal type into a press, but panels of originally hand-drawn color artistry with hand-written dialogue in bubbles, when Jerry Siegel and Joe Schuster made one story, I'm sure they didn't redraw however many hundred or thousand (I don't know what scale "mass production" was at in their days, but I suppose it was more than a handful), how exactly was the load to be sold made? An army of lower-paid re-drawers? If technology, what were they using at that time? 75.75.42.89 (talk) 05:39, 9 March 2015 (UTC)

History of printing has a timeline which shows which printing methods were available in 1900. I'm not sure which were used for comics, though. StuRat (talk) 05:52, 9 March 2015 (UTC)

Easy. Four-color press. In 1896, the New York World was the first newspaper to use a four-color press, the result being the first color supplement and the first color comic, The Yellow Kid. --jpgordon 06:08, 9 March 2015 (UTC)

Mass produced comic books did not become popular until the 1930s, and by then, four color printing was 35 years old, and was sophisticated and highly automated. Cullen Let's discuss it 06:16, 9 March 2015 (UTC)

See our article Comics artist - there is generally a penciller, an inker, a colorist and a letterer. I suspect it was the same then, although some would probably have been done by less people. Richerman (talk) 07:35, 9 March 2015 (UTC)

I'm not sure any of the above completely answers the question. As I understand is, the core of the question is how the printing plates, i.e. the negatives from which the actual paper copy is produced, were made. Offset printing is one answer, becoming available in the early 20th century. Before that, I suspect that artists had to manually prepare the printing plates, either via etching or engraving. --13:01, 9 March 2015 (UTC)

For information on the team of artists see Superman#Publication. For information on the process used see . Richerman (talk) 17:07, 9 March 2015 (UTC)

None of which describes what process was used in the real early days, before the advent of offset printing (in 1904). Indeed, how were the color seps created in the 1890s? --jpgordon 18:16, 9 March 2015 (UTC)

Experimental report evaluations

Why do some experimental report writing guidelines advise against mentioning some types of human error such as reading off scales wrong or breaking fragile equipment or samples. Is this because it erodes the readers confidence in the results? 194.66.246.24 (talk) 10:59, 9 March 2015 (UTC)

If those sorts of errors were involved in the collection of that particular dataset, it should have been repeated from the start, not reported at all. 131.251.254.154 (talk) 13:16, 9 March 2015 (UTC)

Beginners often have a tendency to err on the side of giving too much information. Unless the specific nature of an error is necessary to allow a reader to evaluate the paper or to be able to repeat the study, is is often sufficient to say that an error occurred causing data to be lost. Unnecessary detail makes a manuscript hard to read and understand: readers assume that if a piece of information is included, then it must be important, and they end up wasting time trying to figure out why it is important. Looie496 (talk) 16:11, 9 March 2015 (UTC)

Thrust Reversal - do the "thrust Reversal" doors take a force equal to the braking force on the aircraft?

On watching bucket-type Thrust reversal doors when in a plane during landing I noticed that the doors appear to be hinged on a quite small bolt. This made me wonder whether the doors, and hence the bolt, need to take a force equivalent to the braking force from the reverse thrust on the airoplane. My physics is probably at a bit more than high-school level, so fluid dynamics calculations are beyond me, so I was thinking in analogies with other mechanisms which reverse the direction of a force, such as levers and pulleys which obviously to lift a kilogram must support the weight of a kilogram.

Also - what would happen if a bolt did break and the doors flew off - would the plane come off the runway or is it something the pilot could correct for? -- Q Chris (talk) 11:16, 9 March 2015 (UTC)

The reverse thrust on each engine is applied to the buckets. However, there are two buckets on each engine so each bucket experiences only half the reverse thrust applied to its engine. The buckets are hinged about a pair of bolts, but there is also at least two other structural members that open and close each bucket, so the force on each bucket is divided between the bolts and the other two structural members. Finally, the reverse thrust developed by a jet engine is no more than about 60% of the forward thrust that can be developed by that engine.

When a pilot selects reverse thrust on all engines there is always the risk that it won't operate on one engine, leading to asymmetric reverse thrust. The authority of applying full rudder at touch-down speed must be sufficient that the pilot can manage this level of asymmetric thrust. Similarly, if reverse thrust operates normally after touch-down but later fails on one engine, the pilot must be able to manage the resulting asymmetric thrust using the rudder and asymmetric wheel braking. If the pilot feels the aircraft is at risk of drifting excessively off the runway center-line, for any reason, the pilot can cancel the reverse thrust at any time, as well as using asymmetric wheel braking. Dolphin (t) 12:26, 9 March 2015 (UTC)

If the thrust reversal mechanism broke off, it would be a "flight control malfunction" per 49 C.F.R. §830.5(a)(1) (and probably several line-items in paragraph (a)(7) as well). What does this mean to mere mortals? It means that for legal purposes, a thrust reversal failure as you described is considered (by the NTSB) to be equal in magnitude to the wings falling off and the airplane exploding. It doesn't get any worse, as far as the NTSB is concerned. The operator must immediately notify the NTSB and a full Federal investigation will ensue. The occurrence and its investigation report will enter the public record for all to see.

So, airline operators and aircraft designers work really hard to ensure that won't happen. The thrust reversal mechanism is designed to be sturdy enough to operate within the limitations of the aircraft. Airline pilots who fly such aircraft know how to safely use the system without breaking it. The very elaborate maintenance and accountability-chain works to prevent mechanical malfunction before it ever happens.

Even still, accidents happen; but you can bet that the aeronautical engineers who design these systems work hard to prevent it. Nimur (talk) 14:41, 9 March 2015 (UTC)

Also: The Airplane Flying Handbook has an overview chapter (15-14) on thrust reversers, giving a very high-level overview of the topic and the aerodynamic principles. The AFH directly refers you to the approved flight manual for each aircraft - all your safety and emergency/recovery procedures would be in the aircraft's manual. You can buy manuals for small airplanes on the web or at your local airport - but be advised that air transport category aircraft (like jets that have thrust reversal) are very expensive. If the jet costs a few thousand dollars per hour to operate, expect to pay a few hundred dollars for its operation manual. You can find lots of PDFs of, say, the Boeing 737-200, on the web - but most of these are "flight sim" game manuals and don't accurately reflect real emergency procedures. If you want the real deal, you need to get in touch with the manufacturer's sales representative. Nimur (talk) 15:08, 9 March 2015 (UTC)

Thanks everyone - there was a lot of interesting information -- Q Chris (talk)

Naturally occurring cloud chambers?

Is it at least theoretically possible for certain meteorological conditions - saturated vapour in the air, warmer above, cooler below - to lead to a naturally occurring cloud chamber? - would be fun to see the ghost trails of muons flipping through the air as you walk through the countryside... My understanding is of the lay type, by the way - for a start, I don't understand why it has to be alcohol vapour and not water vapour in the chamber - is it just because it's more volatile?

Adambrowne666 (talk) 12:11, 9 March 2015 (UTC)

Yes, alcohol is typically used because it has a higher vapor pressure at moderate temperatures, and so it is easier to produce the (very) supersaturated vapor required for the cloud chamber effect.

While I haven't found any references to beautiful and striking condensation trails in the air - finding natural situations with appropriate ambient light, sufficiently-supersaturated water vapor, and sufficiently calm air seems difficult - I have found a couple of reports of ionization-induced cloud and droplet formation.

In 1962, Bernard Vonnegut reported on his visit to Yellowstone National Park, where he engaged in some experiments above and beyond those normally carried out by the typical tourist. In a letter to the Journal of Atmospheric Sciences, Vonnegut described how the necessary conditions for supersaturated water vapor formed above geothermally-heated springs and pools in the park, where near-boiling surface water sat just below sub-freezing winter air: . (This is an inversion of the geometry of a typical manufactured cloud chamber, which places a cold surface below the vapor.) He carefully extended a 500 microcurie polonium source(!) over the surface of the hot spring, and observed "...a small but distinct little cloud of fog could be seen beneath it, which indicated that condensation was probably occurring on the fast ions produced by this source." (Go ahead, just try to get permission from the National Parks Service to try the experiment again today.)

Much more recently (2014), the Journal of Aerosol Science published a report from Jan Hovorka et al., describing the curious case of a cistern (a well for water) in an abbey in the Czech Republic: . Even on clear and sunny days when no rain falls from the sky, drops of water can be observed falling on the surface of the water deep in the well (about 19 m below ground level). The paper's authors argue that the temperature gradient from ground level to the bottom of the well, combined with the humid conditions and various other factors, are sufficient to produce a layer of supersaturated water vapor in the well. Ionization events occurring within this supersaturated layer are enough to trigger condensation and drop formation, leading to the sunny-day 'raindrops'. TenOfAllTrades(talk) 12:59, 9 March 2015 (UTC)

02:35, 10 March 2015 (UTC)Lovely answer, thank you, Ten - all the better that it references Kurt V's meteorologist brother Adambrowne666 (talk) 02:35, 10 March 2015 (UTC)

Faecal transplants treatment but between species

Copied from WP:RDM. Nyttend (talk) 17:36, 8 March 2015 (UTC)

OK, I didn't know whether to ask this on the relevant wiki or here so forgive me if I'm barking up the wrong tree. Basically, I'm wondering what the consequences of a faecal transplant between two difference species would be, or any references towards this. Let's say, a human having a transplant with a dog. Or a horse. Or even a primate. What about the opposite? — Preceding unsigned comment added by 89.151.151.176 (talk) 10:10, 8 March 2015 (UTC)

Can we assume you mean facial transplant, not faecal? Ghmyrtle (talk) 10:38, 8 March 2015 (UTC)

Nono, see http://en.wikipedia.org/Fecal_bacteriotherapy — Preceding unsigned comment added by 89.151.151.176 (talk) 10:42, 8 March 2015 (UTC)

No answer, but: There is some information in our article on gut flora on faecal / fecal transplants. There is no specific reference to inter species transplants, though one of the references may have data. --Cookatoo.ergo.ZooM (talk) 10:54, 8 March 2015 (UTC)

I doubt it is possible. Human to human transplantation is predictable, we know what infections to look for, and there is plenty of shit in the world. Why take the risk and perform an animal to human transplantation?--Llaanngg (talk) 20:23, 8 March 2015 (UTC)

Well it's almost certainly possible. But I agree with you that it probably isn't a good idea, or an effective therapy. OP can find more related info at our articles microbiome and human microbiome. SemanticMantis (talk) 16:10, 9 March 2015 (UTC)

"not possible" was probably the wrong word here. It's more like impractical, not feasible, or something in this direction. I also don't know whether some animal has the type of bacteria we want to transmit through this treatment.--Llaanngg (talk) 18:47, 9 March 2015 (UTC)

Yes, the whole point of fecal transplants is to help restore a human's gut flora to a state more normal for humans - and it is unlikely that inoculating a human with non-human feces would help accomplish that. SemanticMantis (talk) 20:41, 10 March 2015 (UTC)

Soul and neuron action potentials

Soul#Neuroscience_and_the_soul doesn't seem to give a conclusive answer, but still I wonder whether the origin of an action potential could be a valid inference for the existence of soul. Specifically, science explains the origin of an action potential in chemical terms, but doesn't seem to explain what ultimate cause triggers such a potential, and as such the origin of free will and thought. According to this, for instance, artificial cardiac pacemakers require a pulse generator typically powered by a lithium iodide battery to work. A natural human cardiac pacemaker doesn't require a battery. That said, if you had a real person and completely identical biological doll (with natural heart, natural neurons, natural nervous system, etc.), the doll still wouldn't start to generate cardiac pacemaker impulses by itself (to start the heart and subsequent vital processes, specifically to eat and drink to provide energy for neural action potentials) and would require some kind of battery, as in artificial pacemakers (unlike humans). Is such inference actually valid in scientific terms? Brandmeister 15:42, 9 March 2015 (UTC)

That's an outdated view. We have known for quite a while that many parts of the brain and body are spontaneous oscillators -- particularly the heart. If the heart is healthy, it doesn't need any external signal to start, it will just start automatically. The function of a pacemaker is not to keep the heart going, it is to control the timing of the beats. Even during a heart attack the heart doesn't stop beating for a long time -- what happens is that different parts of the heart lose synchrony with each other, and the muscle contractions become disorganized, resulting in a failure to pump blood properly. (The idea that you're suggesting here, by the way, goes back to the ancient Greeks. Aristotle argued that the difference between living and nonliving things is that living things move themselves whereas nonliving things require something external to start them moving.) Looie496 (talk) 16:02, 9 March 2015 (UTC)

• Humans don't develop from unliving dolls like Frankenstein's Monster needing a jolt of electricity. The life in your body is continuos with that of all life on earth, human eggs or the germ line being no different in essence from single-celled organisms. Some cells die, but all cells come from prior life. That being said, the ability to produce an action potential just depends on a cell's expressing its genes to create various ion pumps and gates which work spontaneously or when triggered. There's never any dead state from which these cells need to be aroused by ensoulment.
  • Yes, but an action potential is not necessarily a response to an external stimulus, it may spark arbitrarily (for instance, in humans to simply walk back and forth without any physiological need). In other words, a neural action potential doesn't seem to be generated by an organism itself. And of course, there are many other examples, where action potentials are not triggered simply to sustain biological functions, such as creative work (arts), etc. Consider, for instance, holding one's breath. The related action potential would not be triggered by an organism itself because it's obviously detrimental to it and after some time your will would be overridden by involuntary inhalation. That's why a person wanting to commit suicide can't kill oneself simply by holding his/her breath and choking by hands, which (in my view) indicates the presence of an independent incorporeal agent within body. I wonder whether this may be regarded as prima facie evidence for soul. Brandmeister 16:26, 9 March 2015 (UTC)

Arguing this in detail is possible - but tedious in the face of someone who clearly doesn't want to believe it. However, I'd like to point out how simple it is to program a computer to do all of these things - and (presumably) you'd deny that my cellphone has a soul. SteveBaker (talk) 18:07, 9 March 2015 (UTC)

• Brandmeister, you appear to be proposing just another twist to the old Dualist position, with somehow (?) action potentials acting as a missing link between the body and soul. A useful review of the history of such ideas, and their current (discredited) status, can be found in the writings of, say, Patricia Churchland (Brain-wise and Neurophilosophy) or Daniel Dennett (Consciousness explained). Read them if you are interested in learning more. Abecedare (talk) 19:06, 9 March 2015 (UTC)

• (Personal comment, perhaps rambling, sorry:) Action potentials occur in the isolated neurons of sea slugs, in cardiac myocytes differentiated on a tissue culture dish, indeed, in isolated pieces of cell membrane in a patch clamp procedure. They are a poor choice for finding the soul. Understand that one can suppose a sufficiently advanced robot acts in a way that perfectly duplicates the actions of someone with a soul; you cannot tell by looking whether it is present or absent; it has no direct physical consequence. Therefore, a soul is a paranormal phenomenon, and one should look for a paranormal explanation: specifically, I'd say one should look for methods by which causality violation can be induced, then think on how new boundary conditions of the cosmos can exist in the present space and time, and what they mean. Wnt (talk) 19:16, 9 March 2015 (UTC)
  • I still see a missing link in the scientific approach. While the said pacemaker impulse, for example, originates in genetic instructions during gestation, where does the action potential for holding one's breath ultimately come from? Brandmeister 20:02, 9 March 2015 (UTC)

For the sake of argument, let's propose that you are right and the soul somehow influences neuron action potentials. How is that different from the hypothesis that action potentials are simply an entirely natural manifestation of physical and biological processes? Under what circumstance would the soul hypothesis predict different results than the biological hypothesis? Are there experiments we can do in a laboratory with cultured neurons? Or maybe in animals, do they have souls that influence their behavior? If only humans are posited to have souls, then how do we see that difference in our own brains? If there is no situation where the influence of a soul can be observed and distinguished from a purely biological process, then invoking a soul as an explanation is at best a non-scientific idea. Many people have faith in non-scientific ideas, and such ideas often give them comfort, but it isn't generally rational to take non-scientific ideas and expect to find scientific justifications for them. Dragons flight (talk) 20:41, 9 March 2015 (UTC)

It's fairly well known that basically there are two kinds of action potentials: those controlling involuntary actions such as heart beating and those mediating control over voluntary actions, like the said voluntary control of respiration. In other words, there's a clear distinction between what an organism can control by itself and what it cannot control by itself. Also, during disorders of autonomic nervous system, which controls involuntary processes, people can sense that something is not normal by themselves, i.e. during urinary incontinence, erectile dysfunction, etc. Now, per action potential, the voltage-gated ion channel generate a potential when they rapidly begin to open if the membrane potential increases to a precisely defined threshold value. What causes the membrane potential to increase to a precisely defined threshold value when holding breath, for example? That still evades me, unless soul is invoked. Brandmeister 21:36, 9 March 2015 (UTC)

The sum of all your prior observations, preferences and decisions produce that action potential. You smell smoke, you don't like the smell, you figure you can cross the area quickly enough that you won't need to breathe. All this depends on prior action potentials and neural connections, your development since conception. It's action potentials all the way down. To paraphrase Christopher Hitchens in his last book, You don't have a body, you are your body. μηδείς (talk) 01:15, 10 March 2015 (UTC)

If you are interested in breathing specifically, you might be interested in control of ventilation which discusses some of the underlying physical processes. The beating of a heart is fully automatic. Moving my arm is voluntary. Breathing is really in a third category, automatic processes that can be voluntarily modified. In general, breathing is an automatic process most of the time. We don't have to actively think about it, and it continues if a person is asleep, unconscious, or loses higher brain function. However, we are also able to consciously intervene and hold our breath (in principle until one passes out, though I don't recommend trying that). Animals also can hold their breath, most notably when swimming, but also in other situations. Aside from being in the middle ground between automatic functions and voluntary ones, I'm not sure why you feel breathing is special, or what role in breathing you are assigning to a soul. In your view, is the soul what keeps us breathing or what allows us to hold our breaths or what? Conscious choice (or the illusion of choice) is still a fairly mysterious thing, but that extends to all voluntary behavior. I'm not sure why holding one's breath is special in that regard. Dragons flight (talk) 01:41, 10 March 2015 (UTC)

He seems to be asking what is the prior cause of the action potential that overrides the normal breathing process and causes the breath to be held. Again, it's simply a sum of prior action potentials signaling the presence of smoke, fear or dislike of it, and prior experiences over the years which have caused certain neural pathways to develop leading up to this point. Holding you breath as you drive past a pig farm is not something that suddenly happens just then, it required two decades of physical development from an egg, and all the experiences and decisions that have been made over the years to set up your brain so that it is capable of making this choice at this time. There is no special intervention at any point. Nor is there really any such thing as an instant--that's a complex abstract idea that we have that allows us to imagine that at one instant "we" as opposed to "our bodies" made a decision. There is no such instant, just a constant flow, and just as we are our bodies, we are also our individual pasts. A choice is not an instant without a physical cause, it's just a hugely complex event that is a result of your entire history. μηδείς (talk) 04:52, 10 March 2015 (UTC)

Yes, again, just to clarify, I'm specifically asking about an action potential originating without prior stimulus at any given time, like the said respiration control at any given time without external stimulus (no unpleasant smell, smoking, etc) or simply moving one's hand or leg arbitrarily, or whatever body part we stupidly wish. Btw, while unconscious normal breathing is controlled by brainstem, the action potentials to hold one's breath come from another source, cerebral cortex. Brandmeister 09:13, 10 March 2015 (UTC)

There's no such thing. There may be some cause internal to the cell that makes it fire "spontaneously" from an outside perspective when some threshold is met inside the cell. At no point is there anything that doesn't happen as a result of the arrangement of the chemical parts of the cell, which is a result of prior causes, prior external stimuli and the expression of certain genes within the cell. If you are going to continue asserting there are certain action potentials that have no physical cause at all you are going to have to prove it. μηδείς (talk) 21:52, 10 March 2015 (UTC)

Power needed for a 4-inch fan

How much power is needed to run a 4-inch fan?. The fan is to be used for venting air from a small bathroom, and has only one speed. Bh12 (talk) 15:50, 9 March 2015 (UTC)

Turning the fan requires torque (i.e. a twisting force). The article on Torque describes the relationship between torque, power, and energy, as well as different ways to calculate torque. Note that power is work done over a certain amount of time: you'll need to determine what time period you're interested in; if (as I suspect) the fan is powered by electricity, then Kilowatt_hour is a commonly used unit. OldTimeNESter (talk) 16:30, 9 March 2015 (UTC)

Hopefully the device either has a wattage rating or amperage rating written on/engraved in it. If they gave you the amps, just multiply that by your voltage (usually either 110-120V or 220-240V) to get the watts, then multiply by the time used, in hours per day, to get the kilowatt hours used per day. Here's a calculator that accepts common units: . If the device is labelled with units not mentioned there, lets us know, and we can help with the conversion. If the device lacks any specs whatsoever, you may need to get a Kill-A-Watt meter or equivalent, which will tell you the wattage directly. However, if the fan is hard-wired in the wall, that won't work. In that case, try looking up similar fans online to get their wattage ratings. StuRat (talk) 16:56, 9 March 2015 (UTC)

Let me be a bit clearer: Stores sell 4-inch fans for the purpose I described above - what would be a typical power rating for such a fan? 1 watt? 10 watts? Wattever? (please pardon the pun...)Bh12 (talk) 17:19, 9 March 2015 (UTC)

This one is 3 watts: . (Be careful when searching, because I found many larger fans which squeeze the air into a 4 inch duct.)

I'm also shocked at the price. Why should a 3 watt, 4 inch, 1 speed fan, made in China, cost almost $300, when I get a 100 watt, 17 inch, 3 speed box fan, also made in China, for $15 ? At that price I suspect the purchase price of the fan will be far more than the energy usage cost, over the lifetime of the product. StuRat (talk) 17:37, 9 March 2015 (UTC)

Thank you!

Global warming experiments.

I can prove gravity by dropping a ball. I can prove Einsteins theory's by taking a photo of the misplaced stars during an eclipse. I can weigh the earth using a Cavendish torsion balance. I can prove the rotation of the earth with a Foucault pendulum.

I can prove global warming by.... — Preceding unsigned comment added by 86.177.220.245 (talk) 19:03, 9 March 2015 (UTC)

By dressing like this in the summer. Count Iblis (talk) 20:14, 9 March 2015 (UTC)

Lots of ways!

• Launch a satellite that uses radar to measure it's average height above the oceans, collect this data over a decade or so and plot a graph showing sea level as a function of time. If you do that, you'll see it going steadily upwards indicating that the water is expanding due to it's increased temperature.

• Distribute a few hundred thermometers around the globe and take readings from them about once a month for several decades and plot graphs of what they read. Note that the average of their readings is going steadily upwards.

• Photograph glaciers and ice at the poles every year for several decades and plot graphs of the area of snow and ice over time.

...well, I think you get the idea. The problem is that we're looking at a long term trend - and to expect a single experiment, performed over a day or two, to demonstrate this is entirely unreasonable. So unless you have the funding, the skills, and the patience, to undertake these very long term, rather costly, experiments - it's hard to distinguish the subtle long-term climatic changes from the day to day effects of random weather.

That said, there are tests you can make with ice-cores cut in the antarctic that demonstrate year-on-year pollen grain deposition and ice accretion thicknesses that could be done and analysed fairly quickly...but still, it's not something that exactly easy.

You're probably going to argue that you don't trust the people who have done all of those experiments - yet, for some bizarre reason, you DO trust that the ball moves downwards when you release it because of "gravity" - when you could equally suspect that the earth is growing in diameter at an extraordinary rate and that you're feeling that acceleration. There are people (nut jobs, admittedly) who believe that (http://www.circlon.com/living-universe/015-cause-of-gravity.html for example) - and when you try to disprove it, they simply refuse to accept the evidence provided by more indirect means. If you're hell bent on disbelieving a scientific theory and if you're perfectly happy to discard all of the mountains of evidence produced by large-scale experiments for whatever half-assed reason - then I don't think you should accept either gravity, relativity or the weight of the earth since all of the 'experiments' you described are built on previous work, which you ought to doubt if you doubt the experiments that confirm climate change.

What's most significant about all this is that all of the independent ways to determine that the planet is warming up faster than anything other than man-made intervention could produce...all of those experiments agree with each other to a remarkable degree. If we were just seeing glaciers retreat - then maybe we could find other explanations - but the fact that they are vanishing, and sea levels are rising and our weather is getting wilder and the number of tornadoes is going up and we have historic levels of drought in some parts of the world and...yadda yadda...means that we have to dismiss all of those studies - and over the last 20 years, the evidence has just been piling up, higher and higher - to the point where disbelieving it is an act of willful ignorance - self-deceit - wishful thinking.

If you truly need a single, simple experiment - then go find a glacier - take a photo - come back a few years later and take another photo...compare the two...it's not a perfect proof - but then neither is watching an apple fall from a tree proof of gravitation.

SteveBaker (talk) 20:34, 9 March 2015 (UTC)

and if you did that in New Zealand you'd find glaciers are growing, not shrinking. Greglocock (talk) 22:56, 9 March 2015 (UTC)

That's odd I looked at http://en.wikipedia.org/Envisat and http://en.wikipedia.org/Jason-1 and there seems to be a discrepancy in the measurements for sea level rise. I suppose that means that I am insane for questioning it or something.. — Preceding unsigned comment added by 86.177.220.245 (talk) 22:43, 9 March 2015 (UTC)

Unfortunately sea levels are increasing in some places and decreasing in others (be careful of datums) . There may be a global tendency to rise, but then you'd need to account for a lot of other variables before you can be sure. None the less, I think there is good evidence that the earth is growing warmer on some timescale, since we are coming out of an Ice Age. On the other hand as Greenland's ice retreats it reveals farming communities from ~1000 years ago, indicating that perhaps the effects aren't quite as simple as the worry warts would have it. Of course most of the fuss is about whether CO2 is a significant contributor to global warming, which seems to rely on computer models of spectactular complexity and ineptitude.Greglocock (talk) 22:56, 9 March 2015 (UTC)

I gather you're falling for the good old "Greenland used to be green" story. Sounds good but not true. According to the sagas Eirik the Red gave the colony its name not because the land was green, but because he thought an attractive name would induce people to go there -- in other words advertising hype, 985 AD. Can you give any examples of Norse farms that have emerged from the ice? There's Garden under Sandet, but that was buried under alluvial sand (hence the name) rather than ice. Short Brigade Harvester Boris (talk) 04:13, 10 March 2015 (UTC)

Cherrypicking data gives you any result you want to hear, or promote. Such as glaciers in NZ are growing. if you pick one of the 10% that are growing, sure, while ignoring the 90% that are shrinking. That's similar to the percentage of scientists who support most of the findings of the IPCC. Such a unilateral consensus in science is actually rare, I wonder what "insight" someone like Greglocock has that he can so easily and flippantly dismiss 90% of the scientists on earth? Ignoring that 2014 was globally the hottest year on record; that we've had 38 consecutive years of above average temperatures; ignoring even the temperature trend in New Zealand. Vespine (talk) 05:22, 10 March 2015 (UTC)

See also Retreat of glaciers since 1850#Oceania and . There's also these rather famous examples . What makes both Fox Glacier and Franz Josef Glacier particularly funny is as per the various articles including ours, I'm fairly sure both was used as a key examples of NZ's growing glaciers. Whoops. (And if I'm getting the dates right, that's from after they started shrinking again. Double whoops.) I would however agree that these examples show why it's unwise to cherry pick data or choose only a specific example. Nil Einne (talk) 05:41, 10 March 2015 (UTC)

Shrugs, Jared diamond : http://www.newyorker.com/magazine/2005/01/03/the-vanishing-2 - these settlements were obvioulsy farmable/if not sustainably/ at the time, and have recently been uncovered (I think). Anyway, sorry for spooking the hive-mind, I'm quite sure your computer models will continue to reassure you. I am fully aware most glaciers are shrinking, and I agree, the earth is generally warming as we emerge from an Ice Age, My point was that single point experiments aren't much use in isolation. Greglocock (talk) 10:22, 10 March 2015 (UTC)

Have you read the article you linked to? There is nothing about "recently uncovered" (by ice) there. Sites like Brattahlíð have never been covered by glaciers since the time of the vikings, and we have known about them since the time of the sagas. Gladwell's exposition of Diamond explains the downfall of the Norse settlements in Greenland (and the reduced greening) not by any change in climate, but by over-harvesting of wood, overgrazing of meadows, and the resulting soil erosion, which destroyed the foundation of local agriculture. There probably was some temporary shift in local climate as well, but that's not in your source, it's over, and it was much less dramatic than you seem to suggest. --Stephan Schulz (talk) 10:49, 10 March 2015 (UTC)

On 'None the less, I think there is good evidence that the earth is growing warmer on some timescale, since we are coming out of an Ice Age', actually we should probably already be entering another ice age given the pattern in the last couple of million years. There's dispute over that like anything to do with climate but the last ice age ended about 10,000 BC and as far as I can see the evidence leans towards that it should have started getting cooler but human activity has reversed that. Dmcq (talk) 17:39, 10 March 2015 (UTC)

The point here is that this is a long-term, global climate change. Every one of those words are important. You can't measure the temperature on Feb 20th in Milwaukee on four consecutive years and decide that we've had a bunch of bad winters in a row, so the world is cooling. You need to measure over the entire planet ("global") and over decades ("long-term") - and you're looking at climatic changes (very broad effects) and not local weather differences. One or two glaciers may well be growing - but if most of them are shrinking, and have been doing so for a decade then the global answer is that "glaciers are shrinking" - and that's what we care about. A few bad winters or crazy hot summers in a few places in the world would be no surprise and probably no cause for alarm. But a world-wide (average) change that's sustained (statistically) over decades is decidedly terrifying.

This point is underscored by these 'polar vortices' that are hitting North America repeatedly this year and the last. If you happen to live there, it looks a lot like the world is cooling - but that's because the normally stable airflow around the arctic is being disrupted by a global pattern of temperature increase - causing that "polar vortex" to start to spin out of control. Locally "weird" weather is perhaps another symptom - but measuring it that way doesn't work. You need global measurements over decades to see this unmistakable trend.

SteveBaker (talk) 17:43, 10 March 2015 (UTC)

If you want one experiment respecting global anthropogenic climate change, then the most famous individual experiment is probably the NOAA measurements of monthly mean atmospheric carbon dioxide at Mauna Loa Observatory, Hawaii. This is a famous, decades-long measure of carbon dioxide concentration (not temperature). In isolation, it is not sufficient to prove very much at all. But, it is the most famous experiment because the data product is easy to visualize; because the signal-to-noise ratio is very high; because the quality and integrity of the measurements are excellent. This experiment is often cited in other literature. The data is correlated to temperature. A causal hypothesis exists and can be tested against the data.

If you're going to nitpick the data, or even if you are going to extoll the virtues of the science, it is a good idea to familiarize yourself with the most famous experiments. Another excellent source of reading-material is the IPCC Climate Change Report 2015, which reviews almost all present scientific efforts related to this area.

Nimur (talk) 17:57, 10 March 2015 (UTC)

I'm well aware of the Mauno Loa observations, but would you really call it an "experiment"? Certainly not a controlled experiment, as we only have one Earth... perhaps OP is a little confused, and is looking for a way to establish global warming via a rigorously controlled experiment -- and that is not available. "Natural experiment" is sometimes used for this sort of thing, e.g. the industrial revolution didn't set out to test the notion that pumping CO2 into the atmosphere would warm the planet, but our observations indicate that is indeed the case. OP may also be interested in the distinction between anthropogenic climate change vs. a general warming trend. The latter is easier to establish, but even the form has overwhelming evidence, we just have to be a little more careful how we structure the arguments. SemanticMantis (talk) 19:34, 10 March 2015 (UTC)

Indeed. NOAA's webpage does not actually call this series of observations an "experiment." They call it a "data set." Nimur (talk) 19:56, 10 March 2015 (UTC)

There are plenty of sciences where experiments in the classic sense are impossible...cosmology, astronomy - for example. Take the Einstein 'experiment' of testing relativity by looking how the sun bends sunlight during an eclipse. The "experiment" was to wait for an eclipse and measure how much the light was bent. But if there had been a bunch of high resolution photographs of the stars close to the sun from previous eclipses ("data") - then it would have been equally valid to go back and look at that historical record to see if light bending was demonstrated in those photos. SteveBaker (talk) 04:33, 11 March 2015 (UTC)

Question to the OP: if you already know the answer, why are you asking us? Asking a question implies some willingness to accept the answer, or at the very least, some attitude other than condescending arrogance. If your only purpose is to be polemical, this isn't the place for you. --Bowlhover (talk) 18:27, 10 March 2015 (UTC)

To be honest , I was simply asking a question (Like Feynman, I like to ask simple questions to which I don't know the answer for). There seems to be an EMOTIONAL quality to peoples responses to this issue . The first thing I picked up was a discrepancy from the satellite data for the sea level rise. Jason-1 says 3mm a year and ENVISAT 0.5mm a year. This is a fact that should be looked into instead of being shouted down as irrelevant. I want a green planet like everyone else..who doesn't? I am genuinely interested in the science but hate been called a DENIER as soon as I ask a skeptical question. — Preceding unsigned comment added by 86.177.220.245 (talk) 18:05, 11 March 2015 (UTC)

I didn't see very much emotional about the answers above, you are the only one using capital letters for instance and no-one said you were a denier so I would say you are the most emotional and are simply projecting your feelings on others. As to sea levels there can be local variation, for instance the average sea level for the last couple of years on the east coast of America was higher than the average global rise due to climate change, this is due to a change in currents in the Atlantic which happens every so often . Dmcq (talk) 19:58, 11 March 2015 (UTC)

The thing is that you can find small discrepancies in any very large data set - but that doesn't allow you to disregard the whole thing. Sure, if those two sea level studies come out with 3mm and 5mm as their answers, then you don't know what the actual rise is - but you can say with fairly high confidence that the sea level is rising and not staying the same or falling. Add that to the other studies about sea level change - and that adds further weight - then look into ocean temperature studies, and those are showing an upward trend too...and on, and on, and on. Since few (if any) of the significant studies show a trend in the opposite direction - it is an overwhelmingly clear that we must say "The planet is warming and mankind is the cause". Now, when you come to ask whether some specific city is going to be overwhelmed by the ocean on some particular future date - then the issue of whether the ocean rise is 3mm or 5mm starts to become of paramount importance. Just how long will it be before New York needs a flood barrier like the one London has? The degree of uncertainty in the numbers makes that prediction difficult - and doubly so because we have to include the (increasingly remote) possibility that everyone will come to their senses and start working to fix the problem. So make no mistake, there is certainly doubt and controversy about the magnitude and imminence of the problem - but there is really zero doubt that it's happening.

Another thing to be concerned about is the risk involved here. The utterly disasterous consequences of assuming that climate change is not occurring, despite all of the experimental data, are pretty extreme. We might lose the planet - we could definitely see the end of civil society and great civilizations - and we'll most definitely cause ungodly amounts of environmental damage. On the other hand, if we assume that climate change is real - and against all odds, it's not - then we'll have spent perhaps 10% of GDP on fixing a bunch of things that needed fixing anyway. The potential loss we assume that climate change is happening is absolutely humungous compared to the loss if we assume that it's not happening, when in fact it is. So if there were any shadow of doubt whatever about the answer here - either way - then we should still mobilize humanity to fix it.

As for the emotion...you must understand that people here on this science reference desk are overwhelmingly interested in the answer that science provides - which is that climate change is real. We very often get people coming here seeking to push the skeptical position - and it's unsurprising that we're going to be a bit on-edge when that happens. I know that I won't live long enough to be terribly inconvenienced by climate change - but I also know that my son most certainly will feel the effect - and our four grandchildren may well find themselves in a terrible, irrecoverable disaster that will utterly ruin their lives. That degree of importance makes me want to take each one of these (frankly, idiotic) deniers firmly by the throat and beat the freaking obvious facts into their dumb-assed skulls until they understand the importance of what we now know.

In your case, it's tough to understand your interest in a single, simple, fundamental experiment that would undeniably show that there is or isn't a problem. I've heard very many of the nut-job deniers (eg members of the US Republican party) use exactly this argument ("There is no experiment anyone can do to prove climate change") as a way to carry on the way we are. It's an absolutely stupid argument, because (as I've tried to point out), this is not a problem that can be investigated in that way. The very nature of a slow effect that produces only an average change when you examine the entire planet means that such a single, simple experiment is impossible...but that in no way means that we don't know the answer...we certainly do.

It's worth pointing out, again, that not one of the experiments you described as being of the simple, easy, conclusive kind are actually anything of the sort. Every one of them relies on a huge mountain of knowledge that had to be acquired before the conclusion could be arrived at. For example, the bending of light by the sun, demonstrating the truth of Einsteins theory of relativity...I might (as a skeptic) suggest that the sun's atmosphere might extend out far enough to cause refraction of the light through it. OK...so tell me again how your experiment proves relativity? It only does so because we know about the sun's atmosphere and about how light is refracted by it. And your complaint about those two satellites showing differences in the sea level rise is precisely mirrored in the different angles calculated for the light bending by the two teams who set out to measure it. They could only say that the amount of light bending was NOT INCONSISTENT with Einsteins finding - and too much to be explained by the previous prevailing theories. Same deal with the ocean rise. The two increases noted are NOT INCONSISTENT with global climate change - and are too much to be explained by "situation normal" variations. Science rarely proceeds with absolute, perfect experimental results - yet, by collecting statistically valid spreads of results, we've been able to put together all of the astounding amounts of technology that allows you to read this post. Science works....it truly does...even when there isn't a single, clear result but only a gigantic mountain of slightly fuzzy results that all point in the exact same general direction. SteveBaker (talk) 20:38, 11 March 2015 (UTC)

Envisat shows 0.5mm rise , not 5mm rise. — Preceding unsigned comment added by 86.177.220.245 (talk) 22:19, 11 March 2015 (UTC)

¿Que? Short Brigade Harvester Boris (talk) 12:18, 12 March 2015 (UTC)

If you want to quibble over such a detail - and it's fine if you do ... plenty of us here love quibbling over technicalities! We're volunteering our time to read and discuss long boring scientific reports! - at the very least, please cite a source! Who showed this data? What exact result did they present? When did they show it? Where did they publish their findings? Why did you feel like you could post a specific scientific fact without a reliable source to back it up?

Here is Envisat's webpage from the ESA. As you can see from the photographs, Envisat is an observation satellite, and as such, it is an inanimate object incapable of actively demonstrating any scientific premise. Furthermore, it has been missing in action (or at least AWOL) since 2012. Perhaps you are misattributing the work of some human scientist to this satellite. The complicated process of analyzing archived satellite data is not commonly performed by inanimate scientific equipment. Nimur (talk) 13:50, 12 March 2015 (UTC)

http://en.wikipedia.org/Envisat#RA-2 — Preceding unsigned comment added by 86.177.220.245 (talk) 22:33, 12 March 2015 (UTC)

Spec/Glass

Hello,

Has anyone seen the eyes of the mask in the Movie: The Amazing Spiderman? It’s from a spec I forgot the name of. I wrote many rubbish in the google and unable to find even an image of it.

Description: The spec does not have a glass in its glass holder frame, it has a plastic kind of thing with many little holes in it.

Does anyone know the name of the spec/glass?

(SuperGirlsVibrator (talk) 21:52, 9 March 2015 (UTC))

I'm not sure that I understand your question, and I haven't seen the movie; but are you referring to something like pinhole glasses? Deor (talk) 23:48, 9 March 2015 (UTC)

Yep! I've looking for this for few years! Thank you! -- (SuperGirlsVibrator (talk) 07:26, 10 March 2015 (UTC))

March 10

Can it be an isotope with less neutrons than the number of its atom?

149.78.32.22 (talk) 03:27, 10 March 2015 (UTC)

Hydrogen is an isotope with zero neutrons, and therefore less than the number of its atom, so yes. --OuroborosCobra (talk) 03:32, 10 March 2015 (UTC)

Anything with n < Z at Table of nuclides (complete). PrimeHunter (talk) 03:40, 10 March 2015 (UTC)

So, is there only one isotope with less neutrons comparing to the number of its atom? (hydrogen)? 149.78.32.22 (talk) 03:48, 10 March 2015 (UTC)

No, there are many. You can do your own research by clicking any of the elements in the table below, and searching for ones with less neutrons than protons. --Jayron32 04:01, 10 March 2015 (UTC)

Hydrogen 1 is the only "dominant" isotope.

Helium 3 is the most famous; it's an excellent fusion fuel with few hazardous byproducts (for example no neutrons, duh). H and He are the only stable ones.

Be, C, C, N, O, O, F each have half-life of minutes or more. - ¡Ouch! ( / _{more pain}) 10:15, 10 March 2015 (UTC)

v t e Isotopes of the chemical elements
Group 1 2   3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Period Hydrogen and alkali metals Alkaline earth metals Pnicto­gens Chal­co­gens Halo­gens Noble gases ① Isotopes § ListH1 Isotopes § ListHe2 ② Isotopes § ListLi3 Isotopes § ListBe4 Isotopes § ListB5 Isotopes § ListC6 Isotopes § ListN7 Isotopes § ListO8 Isotopes § ListF9 Isotopes § ListNe10 ③ Isotopes § ListNa11 Isotopes § ListMg12 Isotopes § ListAl13 Isotopes § ListSi14 Isotopes § ListP15 Isotopes § ListS16 Isotopes § ListCl17 Isotopes § ListAr18 ④ Isotopes § ListK19 Isotopes § ListCa20 Isotopes § ListSc21 Isotopes § ListTi22 Isotopes § ListV23 Isotopes § ListCr24 Isotopes § ListMn25 Isotopes § ListFe26 Isotopes § ListCo27 Isotopes § ListNi28 Isotopes § ListCu29 Isotopes § ListZn30 Isotopes § ListGa31 Isotopes § ListGe32 Isotopes § ListAs33 Isotopes § ListSe34 Isotopes § ListBr35 Isotopes § ListKr36 ⑤ Isotopes § ListRb37 Isotopes § ListSr38 Isotopes § ListY39 Isotopes § ListZr40 Isotopes § ListNb41 Isotopes § ListMo42 Isotopes § ListTc43 Isotopes § ListRu44 Isotopes § ListRh45 Isotopes § ListPd46 Isotopes § ListAg47 Isotopes § ListCd48 Isotopes § ListIn49 Isotopes § ListSn50 Isotopes § ListSb51 Isotopes § ListTe52 Isotopes § ListI53 Isotopes § ListXe54 ⑥ Isotopes § ListCs55 Isotopes § ListBa56 Isotopes § ListLu71 Isotopes § ListHf72 Isotopes § ListTa73 Isotopes § ListW74 Isotopes § ListRe75 Isotopes § ListOs76 Isotopes § ListIr77 Isotopes § ListPt78 Isotopes § ListAu79 Isotopes § ListHg80 Isotopes § ListTl81 Isotopes § ListPb82 Isotopes § ListBi83 Isotopes § ListPo84 Isotopes § ListAt85 Isotopes § ListRn86 ⑦ Isotopes § ListFr87 Isotopes § ListRa88 Isotopes § ListLr103 Isotopes § ListRf104 Isotopes § ListDb105 Isotopes § ListSg106 Isotopes § ListBh107 Isotopes § ListHs108 Isotopes § ListMt109 Isotopes § ListDs110 Isotopes § ListRg111 Isotopes § ListCn112 Isotopes § ListNh113 Isotopes § ListFl114 Isotopes § ListMc115 Isotopes § ListLv116 Isotopes § ListTs117 Isotopes § ListOg118 ⑧ Isotopes § ListUue119 Isotopes § ListUbn120 Isotopes § ListLa57 Isotopes § ListCe58 Isotopes § ListPr59 Isotopes § ListNd60 Isotopes § ListPm61 Isotopes § ListSm62 Isotopes § ListEu63 Isotopes § ListGd64 Isotopes § ListTb65 Isotopes § ListDy66 Isotopes § ListHo67 Isotopes § ListEr68 Isotopes § ListTm69 Isotopes § ListYb70   Isotopes § ListAc89 Isotopes § ListTh90 Isotopes § ListPa91 Isotopes § ListU92 Isotopes § ListNp93 Isotopes § ListPu94 Isotopes § ListAm95 Isotopes § ListCm96 Isotopes § ListBk97 Isotopes § ListCf98 Isotopes § ListEs99 Isotopes § ListFm100 Isotopes § ListMd101 Isotopes § ListNo102
Table of nuclides Categories: Isotopes Tables of nuclides Metastable isotopes Isotopes by element

See also Neutron-proton ratio. Simply eyeballing the adjoining graph, it would seem that every element with atomic number <47 has at least one known isotope with fewer neutrons than protons. (Recommend that you double check that with the source database directly, if you intend to cite this as a fact anywhere.) Abecedare (talk) 04:48, 11 March 2015 (UTC)

ICT 100 invented by Feriz Delkic

Hi My name is Almira P. I recently met person by the name Feriz Delkic who 25 yrs ago invented ceramic coating ICT 100. Used by Nasa and USA Navy . When ceramic coating is applied can endure high temperatures over 1800 F He lives in Ponte Vedra beach FL. I came on your web to find out more about this man and I was surprised not to find anything ??? — Preceding unsigned comment added by 2602:306:3054:45D0:A11E:58FD:7835:DA5C (talk) 08:18, 10 March 2015 (UTC)

Hi Almira P. As I understand it, Misplaced Pages is missing a lot of articles it might have. In this case, the problem may well be that no newspapers/books/TV shows/etc have written about Feriz Delkic. Misplaced Pages's rule is to wait until this happens, then report on what the journalists said. 184.147.127.2 (talk) 15:00, 10 March 2015 (UTC)

If you google his name the only information that comes up about him is that he is the President of Delkich International Technical Ceramics Inc. Unfortunately that's not enough information for an article, for which we need information from wp:reliable sources to establish that he is notable enough for an article (see: wp:notability). Richerman (talk) 15:33, 10 March 2015 (UTC)

Their website is here, and the product in question is ITC100-HT. WP:CORP is our relevant notability guideline. See Ceramic engineering for our article on the subject. Tevildo (talk) 00:39, 11 March 2015 (UTC)

Our standards for notability often seem rather harsh - but we need to produce evidence for everything we say about someone. If we were to create an article about this guy - the only things we'd be able to say are things that are published out there for people to refer to. In this case, it seems that there simply isn't enough written about him to support a reasonable article. We can't work from anecdotes from people who knew him or other hearsay information. Worse still, we have even stricter rules about biographies of living people (enshrined in WP:BLP) - because mistakes in articles like that can be very damaging and potentially result in well-justified law suits. I suppose it's unfortunate that a lot of very worthy, useful, clever people never get written about...but that's life. I was one of the team of four guys who made the first CD-ROM - do you see me mentioned anywhere in conjunction with that? Nope - and (at least in part) that's because we worked for a big multinational corporation who didn't go around trumpeting the names of their workers in print. Layered on top of that are our notability criteria. We can't possibly have articles about every human being who ever lived - so we have to have a cut-off beyond which someone simply isn't sufficiently notable to be worth writing about. SteveBaker (talk) 15:07, 11 March 2015 (UTC)

dinosaur

What is the last discovered dinosaur genus?--213.26.205.146 (talk) 12:22, 10 March 2015 (UTC)

Hard to say for certain. I used Misplaced Pages's category system to try to figure this out, and came across Category:Fossil taxa described in 2015. According to that category, only one dinosaur is listed (the rest come from other branches of the Tree of Life). That dinosaur is Qijianglong, which is described as a genus. The first specimens were discovered in the 1990s, though the genus was only classified just this year. This is understandable, as it takes quite a long time for fossils to be identified reliably enough for taxonomists to be willing to identify them down to the genus level, which is a pretty specific taxa, comparatively speaking. --Jayron32 13:11, 10 March 2015 (UTC)

You might find more recent ones among the living dinosaurs. {The poster formerly known as 87.81.230.195} 212.95.237.92 (talk) 14:20, 10 March 2015 (UTC)

Systematics of birds is indeed an active area of research, but usually the debates/advances come through changing of higher order clades, not shuffling genera. See e.g. Bird#Classification_of_modern_bird_orders. It's very rare to discover a "new" genus of birds, and it is also pretty rare for bird generas to be changed/reorganized. All the recent action seems to be in ascertaining the relationships among the *formes orders. SemanticMantis (talk) 20:37, 10 March 2015 (UTC)

pH balanced soap and skin health

Some soaps manufacturers claim to produce soaps with pH of 5.5, and to be healthier than other soaps, with higher pHs. Is there any scientific base to this, or, is it just marketing gimmick? Would a pH 5.5 soap on a pH 5.5 skin have any effect? Isn't it the idea, to have a different pH?--Llaanngg (talk) 15:50, 10 March 2015 (UTC)

You can read a scientific study on this exact topic here. --Jayron32 15:58, 10 March 2015 (UTC)

There's a dead layer of skin on the outside of the epidermis, and a chemical peel is sometimes used to burn through it and remove some of it, giving the skin a more pink (for a Caucasian) appearance. Of course, it takes a seriously imbalanced pH to do that. With a moderate imbalance the effect would be minimal. However, if while washing your face you get some in your eyes, they are considerably more sensitive, so an argument could be made to use a balanced pH for that case. StuRat (talk) 15:59, 10 March 2015 (UTC)

So when the authors of the article linked above say "Each cleansing agent, even normal tap water, influences the skin surface. The increase of the skin pH irritates the physiological protective 'acid mantle', changes the composition of the cutaneous bacterial flora and the activity of enzymes in the upper epidermis, which have an acid pH optimum. The dissolution of fat from the skin surface may influence the hydration status leading to a dry and squamous skin" they're just talking nonsense are they? Richerman (talk) 16:58, 10 March 2015 (UTC)

Soap can definitely have a drying effect on the skin, by removing the normal oils. The solution is simple, though, just use some moisturizer to replace the oils. StuRat (talk) 22:44, 10 March 2015 (UTC)

Does a sports scientist or someone with a BSAT have to take the Hippocratic Oath?

Also, if someone (who isn't a nurse) isn't allowed to dispense medicine or be called a "Doctor" but still treats patients for health issues, does that person have to take the Hippocratic Oath?

175.156.96.153 (talk) 18:39, 10 March 2015 (UTC)

Nobody has to take the hippocratic oath. Not physicians, not surgeons, not internists, etc. And even if they do take the oath, breaking it (in and of itself) carries no penalty in any legal jurisdiction (though of course medical malpractice carries legal penalties in many places, and many times an incidence of malpractice may also constitute a breaking of the oath). See this NYT piece , or perhaps this bit from NOVA for further info.

So the answer to all of your questions is a simple "no" - but of course many physicians do take the oath, and perhaps even some nurses, etc. Actually, you or I could take the oath right now, nobody is stopping us ;) SemanticMantis (talk) 19:28, 10 March 2015 (UTC)

It definitely inspires consumer confidence, in any service industry. If there are two decent restaurants on a block, similarly priced, and one advertises a promise to not harm you, it's safe to bet the competition will follow suit, rather than risk the implication. Of course, there are exceptions, but people tend to take their health more seriously after they're ill. So a Hippocratic Oath means more than a five star safety rating, even if it's less formal.

If a restaurant advertised a promise not to harm me, I'd be wondering why they thought it was necessary to do so.Iapetus (talk) 16:11, 11 March 2015 (UTC)

Unless the oathtaker is a liar, of course. InedibleHulk (talk) 22:56, March 10, 2015 (UTC)

Is there a single entity agreed upon as a universal "Hippocratic Oath"? I mean, the original involves swearing not to do kidney stone surgery or abortions, and I get the feeling it's been reworked considerably. But if it's not a single entity, then what it means to say someone took it or didn't becomes more nuanced. Wnt (talk) 01:06, 11 March 2015 (UTC)

See Hippocratic Oath#Modern use and relevance. As SemanticMantis has mentioned, there's no single form of the oath although some are more popular (such as the Declaration of Geneva) than others, and not everyone even takes any form, depending on university, country and other factors (including what you count as a form of the oath). Some universities give students the option of what oath they want to take, others let them right their own, so even within a certain year of university there's no guarantee it will be the same. And even if there is a single form normally taken, I'm guessing many would allow someone to take an alternative form if they can give reasons they are uncomfortable with the prescribed form. Nil Einne (talk) 01:33, 11 March 2015 (UTC)

Is there a state in the body that for one is health and for the other is pathological?

149.78.30.191 (talk) 20:38, 10 March 2015 (UTC)

Growing a beard on a woman or baldness for a lady could be counted pathological. Hair changing to blond for a dark haired person would be pathological, but the normal state for others. Graeme Bartlett (talk) 21:03, 10 March 2015 (UTC)

Men growing breasts (gynecomastia) — LongHairedFop (talk) 21:10, 10 March 2015 (UTC)

A good and extreme example is Sickle-Cell disease:. There is no such thing as bad genes in the right ecosystem. --Aspro (talk) 21:28, 10 March 2015 (UTC)

I thought he meant something like California. μηδείς (talk) 21:42, 10 March 2015 (UTC)

Yep. Supposes one could say that Californians are in a right State. Especially if there're committing "Californication". No effective medication for that malady other than frequent doses of Red Hot Chili Peppers (ter die sumendum) per orem et auribus (forgive the grammar, as its all greek to me).--Aspro (talk) 22:03, 10 March 2015 (UTC)

My Dad had blocked arteries and claimed that he needed to have what for others was high blood pressure, just to get the blood to move properly. Of course, I wouldn't exactly call that "healthy", but it was healthier for him than if he had a typical "normal" blood pressure. StuRat (talk) 22:40, 10 March 2015 (UTC)

Large Hadron Collider upgrade

IIRC, before the Large Hadron Collider opened the first time, they were already saying that they were going to upgrade it. So they opened it, ran it for a year or so and then shut it down for two years for the upgrade (if I estimate the times about right). Wouldn't it have been better to just proceed with the upgraded version to begin with? Bubba73 22:42, 10 March 2015 (UTC)

they knew it could be better and they needed baseline performance results. Classic process progression. Idea > creation > performance > feedback > areas of improvement > repeat. 66.87.83.115 (talk) 22:48, 10 March 2015 (UTC)

They knew it would be better - is it important to know how much better? It seems like the improved version would have gotten online and started producing results a lot sooner if they had done it directly. Bubba73 22:57, 10 March 2015 (UTC)

Better in what sense? They already could do good science with the original layout. Also, the LHC is very much at the cutting edge of everything, so gaining experience with the less energetic version may well have helped to identify any snafus. The energy in the beam is quite significant - you don't want several TeV to go awry. Also see Perfect is the enemy of good. --Stephan Schulz (talk) 23:13, 10 March 2015 (UTC)

But then it was shut down for a long time for the upgrade. I think better in two senses (1) it must be less expensive to go directly to the upgraded version, and (2) we would be getting results from the upgraded version a lot sooner. Bubba73 23:17, 10 March 2015 (UTC)

and those results could have been: we forgot to tighten the bolt that is allllllll the way inside there and now we have to take everything apart to get to it . Jus sayin66.87.83.115 (talk) 23:23, 10 March 2015 (UTC)

What they did, in my opinion, is kind of like: I need to put a new roof on my house, so I'm putting on one that will last 10 years, but before I do that, I'm already planning to take it off in 1 year and replace it with one that will last 20 years. Bubba73 23:57, 10 March 2015 (UTC)

that assumes that you already know that a "roof" works correctly to block rain snow and elements.66.87.83.115 (talk) 00:07, 11 March 2015 (UTC)

To put it a different way, there's no guarantee it will be cheaper. If you're not sure how to do something, you could easily spend more because you make mistakes you wouldn't have otherwise if you had known before hand. In fact, for the same reason you can't even be sure you'll get results faster. Perhaps more importantly, even if you do get results faster, your results still may not have been as good as if you'd done a better job because you had all the information needed, including that you'd gain from the initial period. BTW, talking about "replace it" is also probably missing another point. I'm not sure how much of the upgrade is actually replacing anything, as opposed to adding new stuff. To use the IPs modification of your example, if you lack sufficient information on how to build your roof, building one with the plan to make modifications after you've learned what you need to know is not a bad bet. And the data already collected isn't useless, I don't know how it plays out in percentage terms but while some of the scientist involved in CERN may be partly helping with the upgrades, and some may be doing other stuff, others are surely working on all the data already collected. BTW, one year seems inaccurate. According to , or if you calculate from the figures in our Large Hadron Collider it was 3 years. I know there were some delays due to the quench incident (although actually I think if you include the time before it's been for longer than 3 years). And of course it likely depended on how quickly they learnt what they need to know, the quicker they could have upgrade. But I have doubts it was ever planned to run for only a year. Nil Einne (talk) 01:10, 11 March 2015 (UTC)

Apologies for any confusion caused by the above post. I should have just waited for others who knew more about this to respond. It does seem the gist of it is largely correct, except for the bit about the replacing vs upgrades (I was somewhat confused by the ref I provided), and also I was unclear on the timeline (the upgrades/replacement only coming after and mostly the result if the quench incident.) Nil Einne (talk) 00:39, 12 March 2015 (UTC)

The original design target was 7 TeV for each beam. However, it was found that not all the superconducting interconnects for the magnets were capable of carrying enough current to run at such a high energy; when one of them failed in 2008, it was a pretty catastrophic event, with large numbers of magnets quenching, loss of vacuum, and six tons of liquid helium boiled off in a flash . The LHC leadership could have gone back to square 1 at this point and replaced everything. Instead, they made a strategic decision to perform an initial run at lower energy, which would be unlikely to trigger a similar failure, and hopefully discover the Higgs boson. As it turned out, this was a well placed wager. The upgrade largely involved replacing and testing interconnects to ensure they would be able to handle the full current needed to achieve the initial design energy. When you say "before the LHC opened the first time," I think you're actually referring to the period of time before the first successful run, but already after the 2008 quench incident. So this was already a fallback plan . That kind of setback is not unusual for such a huge undertaking, with many individual components that have never been attempted before. --Amble (talk) 01:31, 11 March 2015 (UTC)

Politics often trumps science. As it happened, the lower energy runs produced results - hooray! everyone is a hero - and when they ask for more money, it becomes available because they've proven that they know their stuff and can produce big headline news. If they'd shut down until the upgrade was done, it would have been "This LHC is a money pit - we keep throwing more cash at it, and they never produce any results". This was the right way to do it...but that had little to do with science or logic. SteveBaker (talk) 04:20, 11 March 2015 (UTC)

Steve, please stick to topics you know something about. The LHC was already years behind schedule when the disaster hit. High-energy physicists were desperate for data. There were PhD students who needed LHC data for their theses. The LHC's lower-energy runs produced more raw data than the Tevatron did over its entire lifetime, and at a higher energy. It was a huge step forward. Analyzing the data takes years; without the lower-energy runs the experimentalists would have had nothing to do while the LHC was repaired. -- BenRG (talk) 06:36, 11 March 2015 (UTC)

Eh? What I said is in agreement with what you just said...they needed to pause the upgrades of the machine to produce some results to avoid criticism of being years behind schedule. SteveBaker (talk) 14:50, 11 March 2015 (UTC)

You appeared to claim the decision to go ahead at the lower energy levels was little to do with logic or science. BenRG appears to be suggesting it was actually the logical decision and good for science because it still produced a whole lot of data that people are looking at right now (or have already looked at). And in some cases the lack of such data would likely have negatively affected careers not because of criticism of their involvement edit: in the long delayed LHC (realisticly it's hard to blame PhD students for lengthy delays), but because they lacked data they'd been expecting. And so proceeding with the full upgrades/fixes early ony rather than running for those 3 years at lower energy levels was actually the poorer idea from a scientific standpoint, regardless of any possible cost savings, or producing higher energy level results sooner. Or to put it a different way, they primarily didn't pause the upgrades to avoid criticism, the paused because it was the far better choice for science and other reasons (such as being more sure the upgrades were sufficient). The fact that they may have reduced criticism was just an added bonus. Nil Einne (talk) 00:35, 12 March 2015 (UTC)

User:BenRG's answer is the correct one, but it brings up a question in my mind: is a lower-power run a control experiment for a higher-power run? In other words, if I think I found a 0.6-zilliEv particle in the results from a 1-zilliEv accelerator, do I have to run it just as long at half a zilliEv or less in order to show I don't get those results from the lower energy runs? Wnt (talk) 00:42, 12 March 2015 (UTC)

Here's an article from physics.org (a publication of the Institute of Physics): What does the 5 sigma mean? It provides an overview of the way that particle physics experiments validate statistical significance, and it is written at a technical level suitable for the enthusiast up to the intermediate-to-advanced physics student (and beyond). Nimur (talk) 01:01, 12 March 2015 (UTC)

Well, that talks about what five sigma is; I'm just wondering if lower-energy experiments are needed so that they know how many photons, etc. to expect by chance in the first place. Wnt (talk) 13:45, 12 March 2015 (UTC)

I don't think we can answer that in the general case: each specific type of predicted behavior needs its own unique null hypothesis. The process of peer review exists to ensure that experts check the validity of the hypothesis, in addition to verifying details of the statistics and the arithmetic.

Here's a better way to construct your mental picture of the situation. Few reputable physics presenters will publish a result that says something to the effect of "a new particle exists." Rather, that is the domain of the popular press. An actual paper published in Physics Review Letters will take a form more like: Evidence for the spin-0 nature of the Higgs boson using ATLAS data or Study of the Mass and Spin-Parity of the Higgs Boson Candidate via Its Decays to Z Boson Pairs. So, a very specific piece of observational data is studied, and its presence or absence can be checked against an easily-constructed null hypothesis that is appropriate to that exact data point. This may require different settings for the lab equipment, or perhaps not.

My goal here is not to couch an answer in a lot of technobabble; but it's to demonstrate that the hypotheses being tested are actually very specific, even if the popular press reduces the entire experiment to "run at high energy, see new particle." Nimur (talk) 14:11, 12 March 2015 (UTC)

March 11

basic atomic particles

Of the basic atomic particles, the one that would be attracted to a negatively charged metallic plate is the positive particle proton? 00:53, 11 March 2015 (UTC) — Preceding unsigned comment added by 149.78.30.191 (talk)

Can you explain that a little further? The proton would be attracted but that's too obvious. So what prompted you to ask this question. Is there something else on your mind, that you as yet, can not put into words?--Aspro (talk) 01:08, 11 March 2015 (UTC)

In the beginning it seemed to me a difficult, now it's clear, thanks. 149.78.30.191 (talk) 01:14, 11 March 2015 (UTC)

Note that, in this context, a proton would be called a hydrogen ion. StuRat (talk) 16:00, 11 March 2015 (UTC)

What is the reason that the neutron found in the nucleus?

What is the reason that the neutron is found in the nucleus if it's neutral? (all the attraction is between the proton and electron) 149.78.30.191 (talk) 01:10, 11 March 2015 (UTC)

Electromagnetism is not the only force. Atomic nuclei are held together by the creatively named strong force or nuclear force, which has short range, but is much stronger than the electromagnetic force. --Stephan Schulz (talk) 01:18, 11 March 2015 (UTC)

Early information feels more trustworthy. Why?

Let's say on Monday someone tells me that cats are attracted to blue light because mice look blue to them. The very next day, someone else says that they are indeed attracted to certain colors, and indeed it's because of mice, but it's not blue but red. My Monday expert has it all wrong, he says. Both people tell the same story, both have exactly the same credibility, etc. The Tuesday expert might even have more credibility because research has advanced a day.

I've tried to construct an example that has nothing to do with politics or religion, avoiding high horses etc. And even in this case, without a doubt I'd ask if he's really sure about "red", because I'm quite sure I learned it was "blue". I might even start looking for arguments to backup the "blue hypothesis", and would certainly not start looking for arguments to backup the red one. If the Monday expert shows up later that evening, I'd still be on his side and ask for more arguments, while the Tuesday expert is frantically Googling for more proof.

So: is "believing earlier sources more that later ones" a real phenomenon (I think it is but can't find it), and if it is, why? Changing views slowly leads to a more stable life? Humans are bad at changing views because the same berries were poisonous during our entire lifetime 50,000 years ago, and nobody at the time told us you could actually eat them when cooked so we never learned that someone with an opposing view might actually help us? Joepnl (talk) 01:27, 11 March 2015 (UTC)

Sounds like cognitive dissonance. The first thing someone hears and believes in, is easier to cling onto.--Aspro (talk) 01:46, 11 March 2015 (UTC)

Possibly related to availability heuristic? When you learn about it the 2nd time, you already had an opinion formed which is recalled and therefore reinforced? Vespine (talk) 02:48, 11 March 2015 (UTC)

See also confirmation bias. This is where people tend to accept evidence that supports their current position/understand more readily, as opposed to evidence that contradicts it. LongHairedFop (talk) 16:34, 11 March 2015 (UTC)

Possibly anchoring. Definitely not cognitive dissonance. -- BenRG (talk) 02:52, 11 March 2015 (UTC)

• Maybe related to the primacy effect? Not exactly the same thing, but certainly in the same family. --Jayron32 03:09, 11 March 2015 (UTC)

• Law of primacy in persuasion seems to be directly on point. Note though that findings are mixed as to whether the first- (primacy effect), or the last-heard (recency effect) argument dominates, and the result may depend upon the exact set-up (see also this summary). Abecedare (talk) 08:21, 11 March 2015 (UTC)

That is exactly what I meant, thanks! I don't think that the Serial position effect (like the recency effect you and the article link to) really has that much to do with it. From pure introspection, it's only logical that you remember first and last items in a list but recalling items (or ideas) is different from almost stubbornly believing them. I find it strange that the article is almost a stub, based on just two studies. For instance, one effect could be the obvious correlation between a persons religion and that of his parents. For whole societies, Conventional wisdom seems to be researched more, but I wish more research was done to explain why it exists on a personal level as well. Joepnl (talk) 18:41, 11 March 2015 (UTC)

Note that the more time passes, the more distorted the version that gets to you might be, through multiple retellings. So, that's a reason to go with the earliest version. StuRat (talk) 15:56, 11 March 2015 (UTC)

Early psychologist William James discussed "perceptual old-fogeyism." It is the "tyranny of the established." Edison (talk) 20:24, 12 March 2015 (UTC)

Impedance Related Query

Why is complex notation used for impedance and phasors and so great importance in AC cicuit analysis.There is no specific answer to this question in the web save mathematical convenience in solving differential equation.What is explanation fro m physical point of view what is the physical significance and ramifications.111.93.163.126 (talk) 15:01, 11 March 2015 (UTC)

That mathematical convenience is useful, it allows you to exploit certain symmetries that greatly simplify the problems. It's not just the elementary notation using the exponential functions like exp(i omega t), but you can also calculate the response using Laplace transforms and then use methods of complex analysis to relate the dominant asmptotic behavior to the pole closest to the imaginary axis in the complex s-plane. Count Iblis (talk) 17:58, 11 March 2015 (UTC)

See Electrical impedance for our article, which isn't particularly heavy on the maths. To summarize - using complex notation makes it easy to describe the phase and amplitude of a signal independently, and the real component of a signal is a measure of the (physical) work it can do. Tevildo (talk) 22:15, 11 March 2015 (UTC)

Are humans included in "animal research"?

Yes, I am aware that humans can participate in research as test subjects, as long as they fill out an informed consent form. I am just wondering if this process is actually included under "animal research", because humans are animals that can be experimented upon. — Preceding unsigned comment added by 140.254.226.189 (talk) 15:18, 11 March 2015 (UTC)

In this context, I'm pretty sure that "animal research" is understood to mean "non-human animal research". That's something that's hard to prove - but there would be little point in doing a non-human animal study if humans were available as ethically reasonable test subjects. SteveBaker (talk) 15:27, 11 March 2015 (UTC)

The first sentence of Animal testing supports Steve. ―Mandruss ☎ 15:31, 11 March 2015 (UTC)

which doesn't mean that information obtaining from human research cannot be extrapolated to animals, in the same way we extrapolate from rats to humans.Senteni (talk) 16:47, 11 March 2015 (UTC)

Steve is right. "Animal research" means specifically research that uses non-human animals as subjects. Looie496 (talk) 17:08, 11 March 2015 (UTC)

Reliable information from reliable sources

People assume that information is reliable, when it comes from a reliable source. And we assume that a reliable source is reliable because it provides reliable information. That seems to be the case of librarians, wikipedia, and people in general. How can you escape the circularity, without performing all experiments from scratch? That would be difficult in some cases. Do you just have to have faith and go with the herd? 16:44, 11 March 2015 (UTC) — Preceding unsigned comment added by Senteni (talk • contribs)

You develop trust in sources when the information you get from them accords with the information you get from other sources, most importantly your own direct observations. Looie496 (talk) 17:06, 11 March 2015 (UTC)

I would add "other independent sources", to exclude cases where unreliable sources copy each other extensively. Many sources copy Misplaced Pages, for example, but that doesn't make the Misplaced Pages articles they copied any more reliable. StuRat (talk) 06:29, 12 March 2015 (UTC)

In science we only consider things to be a fact if it has been shown in experiments that have been repeated many times by independent research groups. The reuslts will have been rigorously reviewed. The interpetation of the meaning of the results may depend on theories that will have their own experimental foundations that will have undergone similar rigorous tests. You can then always trace back some fact you read about in the literature via the given references all the way to the original experiments or observations, but this will in practice involve a huge number of different experiments. Count Iblis (talk) 17:37, 11 March 2015 (UTC)

One approach I've seen people advocate is to look at a sources reliability on topics for which you do have detailed knowledge of, and on which you can assess accuracy. The reliability of that information is then taken as a proxy for the reliability of the source on other topics which you don't have good information on. Effectively, you're doing a (non-random) subsample over the set of information, and using the sample reliability as an estimator for the population reliability. Another way to do it is to use consistency. If most of the sources are saying the dress is blue, and there's only a few which are saying it's white, then it's more probable that the dress is blue than if it's white. That can also be applied to consistency over time: sources which started out saying it's blue are likely (but not necessarily) more reliable than those which started out saying white and then changed to blue. If you want to get fancy, you can employ Bayesian statistics to exactly quantify how much more - Bayesian statistics works on probabilities as a statement of belief, e.g. belief on how reliable a source is. Bayesian statistics also bring in "prior probabilities" where you can bias sources based on past performance. Generally speaking, you can start off with minimal information about the state of reliability of sources (an "unbiased prior"), and then use a large number of small pieces of information (like consistency of reporting) to establish a (non-uniform) reliability metric for sources. -- 160.129.138.186 (talk) 18:10, 11 March 2015 (UTC)

You can't escape such circularity. It's called solipsism which just means that ultimately, all knowledge rests on trust and faith, and not evidence. At some point, you have to just accept some things, and then make extensions of your knowledge from those unproven axioms. Evidence comes into play in extending knowledge from the unproven stuff. But until you can prove to yourself that you can trust even your senses (which you cannot, see brain in a vat) then you just have to work out for yourself what you're willing to accept as "evidence" and "reliable". --Jayron32 20:41, 11 March 2015 (UTC)

I have found that I could NOT consistently determine a "reliable source" from a "poor source" until I became interested in critical thinking, the scientific method in general and scientific skepticism specifically! The problem is that life and the internet are FULL of experts, experts on UFO abductions, experts on free energy, experts on alternative medicine, experts on religion, etc... And lots of these experts are NOT just "loons" or charlatans, a lot of them are extremely smart and well educated people, sometimes even very charismatic (Dr Oz springs to mind), to most people who do not know how to tell the difference between a reliable source and an unreliable one, these people can be extremely convincing. Vespine (talk) 22:19, 11 March 2015 (UTC)

It also helps to have a healthy understanding of scientific consensus: where it does and where it does not exist; how informed people behave when there are legitimate disagreements about facts and theories; and how to disentangle "wrong" information from "uncertain" information. Informed people who disagree about facts and theories tend to present their case very differently from uninformed people who disagree about the very same details. Nimur (talk) 22:47, 11 March 2015 (UTC)

With all due respect, just about everything Jayron has said is the opposite of reality. What he has described is Idealism (philosophy) of a mystical and skeptical type, along the lines of Kant or Plato, which assumes you cannot know for sure even what simple words refer to in the real world, but you can be absolutely sure of doubt based on the certain knowledge (where did it come from?) of what a "brain in a vat" is. Children do not begin with faith and axioms, they learn simple concrete things, first nouns and verbs for what is available on the percptual level. Then they learn adjectives and adverbs modifying those concepts. Read the works of Piaget.

Even before he can speak, a child learns by exploration what a ball is. Only after he learns to name such objects does he go on to differentiate their properties such as a "red ball". (Color words are always learned after words for simple nouns.) Then he learns how to describe the colors; "bright" red ball. Maybe around five he'll learn through the sum of all his prior experience, and without any faith, to make a certain assertion that, "This is not a very bright red ball."

It is only when he learns that things may not be as we assume from appearances (The moon doesn't follow you, it is far away; the stick in the water isn't bent, that's the way it appears through the surface) and that adults can deceive and be ignorant, does he ever learn what doubt and fallibility are. But he learns that there are reasons for these phenomena, quirks of physics and human psychology. This is still long before he ever acquires an "axiom", but long after he has a vocabulary of thousands of words he understands and uses correctly and with certainty in reality.

Later the child goes to school and learns to read and do simple math. Eventually, if he doesn't live under a cult, he can read on his own, and find out what people besides his elders tell him. He learns more difficult math, and basic science, all of this building on all the evidence he has acquired and induction he has done over his lifetime. He is introduced to things like the fossil record, which he can verify exist on field trips. He learns in chemistry class with the use of his own hands and senses that certain substances he knows of are the basic elements, and that they can react. He learns that a mouse will suffocate in a jar and a plant die under a cardboard box. Unless he's been abused and beaten about the head with nonsense, at no stage has he ever had to accept something on faith, or to derive anything from an axiom. Everything he has learned so far has been based on perception, and the ability to test the truth of things he has been told by experiment.

Finally he learns certain things are not yet known fully (particle physics) or cannot be determined due to distance in time or space. Only at the highschool level has he become prepared by experience to deal with mathematical and logical axioms and proofs. He learns principles like cui bono and Ockham's razor and that "travel broadens the mind." He is taught the comparative method, the scientific method, statistics, probability, how to use a card catalog, and what sort of people to mistrust when they offer him a free lunch (but not until he buys a time share).

None of this is solipsism, the untenable belief that other people don't have minds like your own. The solipsist doesn't try to convince other minds when he doesn't think they exist to be convinced. The person who doubts his senses doesn't know what he's typing on his keyboard. Ultimately the responsibility for judgment does rely on everyone, including you, to think for yourself, as an individual. That's not called solipsism or faith; it's called reasoning. Other people can give you the "answers" but it's up to you to check the math. The only people who demand faith or speak of it are those who demand obedience or want you to accept a lie; a cult leader, an abusive parent, a con-man, or a would-be-dictator. Empiricism, Foundationalism, and Coherentism are all true. Knowledge has structure, the truth coheres, nihil in intellectu nisi prius in sensu. μηδείς (talk) 03:24, 12 March 2015 (UTC)

Solipsism is not untenable, merely unpopular. Looie496 (talk) 14:53, 12 March 2015 (UTC)

Lol! μηδείς (talk) 16:52, 12 March 2015 (UTC)

For the purposes of Misplaced Pages it is not expected to determine what is true, only what is worth considering. Sources that employ rigorous processes, and whose results tend to agree with other sources that use rigorous processes are more worthy of consideration. It is the quality of the process, rather than the result, that determines reliability. Rhoark (talk) 19:45, 12 March 2015 (UTC)

Are diseases/disorders/dysfunctions merely evolutionarily maladaptive phenotypic variations?

Take phenylketonuria, for instance. A phenylketonuric can't break down phenylalanine. In a culture where there are lots of sugary drinks that may have asparatame added, the individual will have an evolutionary disadvantage, unless he adapts to a more restrictive diet and preserves his own life, keeping himself in the gene pool. Will phenylketonuria still be considered a "disorder" if the culture does not consume much of the amino acid in the first place and so the individual's phenotype will never express itself as a problem? 140.254.226.182 (talk) 23:50, 11 March 2015 (UTC)

Some are, sure. Lactose intolerance doesn't much matter in places where they don't drink milk, for instance. But many more are not. The BRCA1 and BRCA2 gene variants that cause breast cancer, for example. StuRat (talk) 23:58, 11 March 2015 (UTC)

Hmmm, phenylketonuria looks like a complicated example. Reading over briefly I see mention of alleles in Polynesians which predate their split from Caucasians, and other alleles dating back to the 5th millennium BC. Such alleles clearly are not rapidly removed by evolution, and have to be considered as adaptive, if only for the heterozygous advantage of ochratoxin resistance. On the other hand, more severe alleles may be more rapidly removed - though if there was mention of the rate of sporadic mutation of the locus in OMIM, I missed it. I don't think that the most severe alleles can be counted as adaptive but I can't say that with authority. As a rule, the "younger" the mutant alleles for a given condition, the less that can be said in their defense. Wnt (talk) 00:28, 12 March 2015 (UTC)

As Stu alludes to above, you can't lump all diseases/disorders/dysfunctions into a neat little group to fit your definition. In fact and some can be viewed as the opposite i.e. "evolutionarily adaptive (or, at least, advantageous) phenotypic variations". See Heterozygote advantage. For example, the same genes that cause the blood disorder Thalassemia also confer resistance to malaria, which then results in that trait being found most commonly in areas where malaria is prevalent. The evolutionary benefits, or "selective survival advantage", of being resistant to malaria outweigh the negative consequences of having (or, more precisely, being a carrier of) Thalassemia.--William Thweatt 00:36, 12 March 2015 (UTC)

March 12

Color-blindness problem

Are any of you familiar with the problem:

Look at this image. Most people should see a 74, but color-blind people should see a 21.

Do you think it is valid for a similar problem to occur with any two 2-digit numbers, with the only requirement is that each digit of the general number must be different from the corresponding digit of the color-blind number?? For example, 74-21, but nor 74-71 or 74-24. Georgia guy (talk) 01:36, 12 March 2015 (UTC)

There are many variations of the test - for example, with pictures for little kids who are too young to understand the numbers. (See tests G and H in this series) I don't see why other number choices wouldn't work. The critical part is the size, tones and shades of the dots. SteveBaker (talk) 01:56, 12 March 2015 (UTC)

Mine must be really bad as I don't even see an image :/ --DHeyward (talk) 06:35, 12 March 2015 (UTC)

I had to zoom in to see it. G is a primitive sailboat, and H is a square and a circle. The rest of them are numbers. ←Baseball Bugs carrots→ 13:54, 12 March 2015 (UTC)

Is it possible to see solar flares during a total eclipse ?

...without any form of magnification ? StuRat (talk) 08:06, 12 March 2015 (UTC)

Original research here. I watched the August 1999 total eclipse in a part of France where there were two layers of broken clouds. I hoped to see the eclipse through a gap in both layers, but couldn't maneuver myself under one in time and ended up in a position where a thin layer of cloud was in front of the sun. Looking at the eclipsed sun with unaided eyes, I saw a ring of white light with several red spots, and was surprised to realize that the corona was bright enough to see right through the cloud layer—nothing I'd ever read had mentioned that that was possible. I then looked through my binoculars and easily confirmed that I was seeing the corona, and that the red spots were prominences. If a prominence can be seen in that way, even through a bit of cloud, it makes sense that the brightness of a flare could be also. --65.94.48.86 (talk) 13:39, 12 March 2015 (UTC)

The phenomenon of visible solar flare appears when charged particles accelerated in the corona hit the lower denser atmosphere of the Sun (lower chromosphere/photosphere). However during a full eclipse these lower layers are shielded by Moon. So, the answer is probably no. Ruslik_Zero 20:37, 12 March 2015 (UTC)

I have seen a sunspot with my naked eyes. We had a bunch of wildfires near where i live and it cretaed a thick haze which was very uniform and it acted like a ND filter, i could look at the sun without any discomfort, (I still only did it for a few seconds because I am aware that invisible radiation might still get through and not cause "discomfort" but still damage my retina). However when I looked at the sun I could see a very distinct black spot, so I jumped on SOHO when I got to work and sure enough, there was a big balck sunspot there. Vespine (talk) 21:28, 12 March 2015 (UTC)

Does alcohol affect appetite?

What it says on the tin, really. Does alcohol intake affect appetite? GoldenRing (talk) 10:28, 12 March 2015 (UTC)

You be the judge: Apéritif_and_digestif 196.213.35.146 (talk) 10:33, 12 March 2015 (UTC)

Chronic alcoholics often show greatly reduced appetite, but alcohol at moderate doses seems to increase both appetite and food intake -- see PMID 15059684 and PMID 11714490. There are however some complications; for a literture review see PMID 18471931. Looie496 (talk) 14:45, 12 March 2015 (UTC)

Note that alcohol itself provides calories, lessening the desire for calories from other sources. However, alcohol, of course, lacks many of the nutrients you need to survive. (I wonder if an alcoholic drink could be made which contains all the nutrients a human needs. Eggnog might be a good start.) StuRat (talk) 17:17, 12 March 2015 (UTC)

Is it possible to purify water from drinking alcohol?

In a situation where an individual has nothing but alcoholic beverages and the individual cannot detoxify aldehydes, is it possible to purify water from drinking alcohol rather than merely diluting alcohol in order to lower the alcoholic content in the water supply? Is 0.01% of alcohol/99.99% water still considered an alcoholic beverage? My first impulse is that the water supply must be distilled. The distillate is separated from the water vapor by differing boiling points, but the water vapor is kept. However, how can a container be made in order to hermetically seal the container collecting the pure water? 140.254.136.157 (talk) 14:41, 12 March 2015 (UTC)

You would lose some of the water in the process. Just leaving it out as the alcohol evaporates and drinking it before most of the water evaporates would be one method, but beware that when the alcohol level drops more bacteria can then survive in the water. Heating it would speed up the process, but beware the alcohol fumes could ignite if you heat it with an open flame.

As for what counts as an alcoholic beverage, see near beer for some legal defs. StuRat (talk) 17:14, 12 March 2015 (UTC)

You can't completely separate the ethanol from the water by simple distillation. Water and ethanol form an azeotrope. There are methods for completely separating azeotropes, though, you can read about them in the Misplaced Pages article. --Jayron32 19:49, 12 March 2015 (UTC)

Hottest natural Lake (without vulkanism/hot springs)

E.G. Lake Natron gets up to 40°C - but hot springs are feeding the lake. Where can conditions be found (maybe salt lake, maybe high humidity in warm climate) where water naturally can reach temperatures above 30(?)°C ? GEEZER 14:48, 12 March 2015 (UTC)

The hottest lake is the aptly named Frying Pan Lake. The lake is also a hot spring. A place without a lake would be likely a hot and dry desert, like the Sahara Desert, which was once an ocean. 140.254.136.157 (talk) 15:08, 12 March 2015 (UTC)

Misplaced Pages has a hot spring article. However, that may not be very useful to you, as it seems to focus on averages of "hot springs", "warm springs", and regular "springs". There are significant overlaps with "hot springs" and "warm springs", so the linguistic distinction is not very useful. Perhaps, a rule of thumb may be looking for a body of water that is at most at 20 degrees Celsius, since that number seems to be a good cut-off point. At that point, it's pretty much saying "water at room temperature". 140.254.136.157 (talk) 15:27, 12 March 2015 (UTC)

Some more reading on hot spring suggests that cold springs just link directly to Spring (hydrology), which may hint that a body of water at 20 degrees Celsius is considered "a cold spring", and you want to find the warmest cold spring? 140.254.136.157 (talk) 15:31, 12 March 2015 (UTC)

One type might be a shallow lake which gets lots of direct sunlight, with dark water to absorb that sunlight. This could occur due to lots of tannins, for example, from decomposing leaves. However, cooling from the surface limits the max temp.

Lakes with a salinity gradient, with cool, fresh water on top and hot, salty water at depth, can theoretically reach up to boiling (100°C) in the lower level: (that article is on man-made solar ponds, but they also occur naturally). StuRat (talk) 15:45, 12 March 2015 (UTC)

Phosphate buffered saline role

Am I correct in assuming that when phosphate buffered saline is added to Trypsin or other enzymes, it dilutes the enzyme and also acts as a cleaning agent? So it has a double role when added to a cell culture flask? 194.66.246.87 (talk) 20:03, 12 March 2015 (UTC)

Are high-speed trains easier to drive?

In comparison to cargo trains, is it easy to drive a high-speed train running on a dedicated track? --Fend 83 (talk) 21:55, 12 March 2015 (UTC)

Cargo trains also drive along a dedicated track, as all trains do. That's what trains do. I'm sure that if you go to your local station and ask, they can give you some information on how to get a license to drive one. KägeTorä - (_虎) (Chin Wag) 22:20, 12 March 2015 (UTC)

I am pretty sure you could do such jokes at another place, like yahoo answers. It's obvious that I was asking about a dedicated high-speed railway line. Fend 83 (talk) 22:41, 12 March 2015 (UTC)

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