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July 25

Line of cooling, line of heating

Is there any map of the USA which shows a line to the north of which you do not require air conditioning in the summer, and to the south you do? And similarly is there a map with a line to the south of which you do not require winter heating? 2.101.4.222 (talk) 09:05, 25 July 2011 (UTC)

What temperatures would "require" air conditioning or heating? I have no air conditioning while the guy I work with has it. If I had to guess, I'd say more people around me don't have air conditioning than do. So, would this requirement line be north of me or south? I would suspect that if you were to draw a vertical line on a map and then poll the households along that line, there would be a gradient for both heating and cooling that is more or less a smooth decline or accumulation depending on which way you go up or down that line. You will at some point reach 0% of homes that has either heating or cooling. So would this be your line of requirement? 0%? Dismas|^(talk) 09:31, 25 July 2011 (UTC)

50% of households would be an appropriate line. 2.101.4.222 (talk) 09:44, 25 July 2011 (UTC)

That's an iffy way to try to collect that data. While air conditioning is very pleasant to have in warm climates, it's not essential for most individuals the way that home heating is. (In the sense of 'your water pipes will freeze solid, then you will die of hypothermia'.) The "50% air conditioned" line will be skewed very heavily by demographics—regions with lower household incomes will be less air-conditioned than higher-income regions. You'll probably also see significant rural-suburban-urban splits. (Dismas' suggestion to look for a 0% air-conditioner penetrance is interesting, but would probably rule out the entire United States. As of 2002, something like 30% of households in Canada had an air conditioner, and that number was steadily trending upwards.)

What you're probably looking for is something like a map of heating degree days (and cooling degree days). That article has both maps for the United States, and a pretty good explanation of what the numbers represent. TenOfAllTrades(talk) 13:50, 25 July 2011 (UTC)

Many homes in the Southeastern United States do not have central heating, even though temperatures occasionally fall below freezing. You could even say the line is variable between different years. ~AH1 ^(discuss!) 15:51, 25 July 2011 (UTC)

Climate on a large continent is not that simple. For example, I live on a state that borders Canada, and it was 102 degrees Fahrenheit last week. I certainly wouldn't want to live here without air conditioning. Washington state, at the same latitude, rarely gets that hot on the coasts, but does inland. So you wouldn't end up with a straight line. thx1138 (talk) 16:32, 25 July 2011 (UTC)

I wasnt suggesting that the line would be straight. 92.29.124.70 (talk) 13:17, 30 July 2011 (UTC)

engineers don't really calculate this; it tends to be trial and error. the calculation of thermal comfort is ASHRAE 55; see LEED discussion: [1]. you could combine the weather data and thermal comfort to get a map, but there would be lines of percentage dis-comfort. (or you could use the plant zone map). 98.163.75.189 (talk) 16:10, 30 July 2011 (UTC)

Better US climate than London

Most of the US, compared to Britain, gets extremely hot in the summer, and extremely cold in the winter. By comparison the average winter temperature in London is above freezing with hardly any snow, and only during infrequent summer heat waves would you appreciate air-conditioning in the home. Nor does it rain much (contrary to US stereotypes) with around 20 inches of precipitation a year.

Which places in the US have a better climate than London? 2.101.4.222 (talk) 09:13, 25 July 2011 (UTC)

Could you better define "better"? I quite like where I live and we regularly get a few feet of snow each winter. To me, that's better than London. But it seems as though you're looking for a place where the temperature range isn't very wide and where there is very little precipitation. Am I right? Dismas|^(talk) 09:23, 25 July 2011 (UTC)

Principally where it is not extremely hot in summer or extremely cold in winter, and preferably with around 20 inches or less of precipitation. 2.101.4.222 (talk) 09:43, 25 July 2011 (UTC)

Again, you'll have to better explain what you mean by "extremely". My niece in Georgia would likely tell me that anything below 20F is extremely cold while I don't mind these temperatures. Moving along though... Well, I don't have a map with a pin in it for you but can provide some links to maps so that you can figure it out on your own... This pdf shows the average rainfall in 2001 as well as average temperature but unfortunately not the range. NOAA has a collection of maps that are relevant. As well as How Stuff Works. This site seems very handy as well. Dismas|^(talk) 09:54, 25 July 2011 (UTC)

Honolulu may be a bit too warm for you, but it never gets unbearably hot. And you can fine-tune average rain fall to your liking by picking the right place between the mountains and the sea. --Wrongfilter (talk) 10:35, 25 July 2011 (UTC)

San Diego has a reputation for an extraordinarily equable climate. See the article Climate of San Diego. Deor (talk) 12:08, 25 July 2011 (UTC)

You might also try Seattle, which does not frequently get much snow compared to higher elevations, though there is an inherent earthquake risk. ~AH1 ^(discuss!) 15:48, 25 July 2011 (UTC)

Drawback to Seattle is it gets around 40 inches of rain a year compared to 20-25 for London, but they do appear broadly similar. Googlemeister (talk) 15:56, 25 July 2011 (UTC)

San Francisco? --Jayron32 16:04, 25 July 2011 (UTC)

Yes, and neighboring parts of California. Los Angeles and San Diego also have nice parts, but if you get more than a mile or so from the beach they are pretty hot. Looie496 (talk) 21:20, 25 July 2011 (UTC)

The inquirer apparently means a mild climate, which means on the coast. NYC, Long Island and Cape Cod are not bad. I personally prefer a winter where it is cold enough to ice skate and a summer warm enough to swim in the ocean without shivering. Most articles on cities give their mean monthly temperatures. μηδείς (talk) 01:11, 26 July 2011 (UTC)

If NYC means New York City, then I thought that it was unbearably hot and humid in summer and below freezing in winter? 92.28.250.101 (talk) 10:40, 28 July 2011 (UTC)

I'm getting the impression that apart from San Francisco and San Diego, everywhere in the US is either unbearably hot in summer or unbearably cold in winter, and in many places both, but never neither. 92.29.113.104 (talk) 22:56, 29 July 2011 (UTC)

Phase diagrams

phase diagram for sulfur

Does anyone know where to find phase diagrams for phosphorus and sulfur, including the allotropes and molecular species present? At what temperature does octathiocane autoignite, does it burst into flame before it melts? Plasmic Physics (talk) 09:58, 25 July 2011 (UTC)

I have the phase map for sulfur it could be found here just before "4 phases at the extremes"--Irrational number (talk) 14:38, 25 July 2011 (UTC)

I typically do an image search on "critical point" and the name of the substance for phase diagrams. Octathiocane says it decomposes at 115 Celsius. 99.2.148.119 (talk) 19:13, 25 July 2011 (UTC)

Phosphorus

For sulfur there is a German phase diagram available on commons. I was converting it to .svg form, but the quality was so low that I abandoned the attempt. It is actually much more complex as at higher temperatures there are mixtures of molecules, including trisulfur and other allotropes of sulfur such as S₆ and S₂ in the gas. What is there depends on the thermal history of the mix. There is a chart for Phosphorus but not a phase diagram here. Graeme Bartlett (talk) 10:22, 26 July 2011 (UTC)

Thanks, good diagram for sulfur, it's a good thing I read german. So, you're saying that the exact composition of sulfur at equilibrium may vary depending on the thermodynamic pathway? Even if several molecular species' thermodynamic domains overlap, there should be boundaries where they do not exist under equilibrium? For instance, disulfur what are it's absolute constraints? Plasmic Physics (talk) 15:28, 26 July 2011 (UTC)

I put up an English version at File:Sulfur phase diagram.svg. (The subscript "8" is still off... it seems like you never know what the svg files will look like after upload, and I had to resort to a Greek en-spacing character to get this much) Wnt (talk) 18:24, 26 July 2011 (UTC)

Where does gamma-sulfur fit in this diagram? It is also monoclinic like beta-sulfur. Plasmic Physics (talk) 00:18, 28 July 2011 (UTC)

Wow. No idea. [2] calls it "notoriously unstable and erratic". Yet it is also the mineral rosickyite, according to the allotropes of sulfur article! (no, alas, that mineral link just goes back to sulfur :( ) We may need a real chemist (or geologist?) to answer this one. Wnt (talk) 18:37, 29 July 2011 (UTC)

Herman F. Becker - WP:N paleobotanist?

Hi all!
IPNI says he's not a taxon authority. A WP:PROD is on foot, and I can't find anything to contest this with, so over to you, the experts.
As always, thanks for all your help and guidance.--Shirt58 (talk) 12:23, 25 July 2011 (UTC)

Whether he is notable or not, his article appears to contain no assertion of notability, which is necessary. You may want WP:N/N instead of the reference desk. 99.2.148.119 (talk) 21:04, 25 July 2011 (UTC)

question about origin of life

I often hear that people and even some scientific programs say that all life on earth is evolve from a single living cell but it doesn't make sense to me because:

a.there is a very small chance of survival for that single cell.

b.the chemical process that led to the formation of life couldn't have happened only one time and produced one cell only because in nature chemical reactions happen in great numbers.

is it a misconception? was it one cell or one "kind" of cell( or even more)?did it only happen in one place or it happened in many places worldwide?thanks in advance.--Irrational number (talk) 14:26, 25 July 2011 (UTC)

Life evolved from single-celled organisms. Not one specific single cell. Zzubnik (talk) 14:36, 25 July 2011 (UTC)

(ec) Your questions are probably answered in this section, current models of abiogenesis. We don't have great certainty, but it is speculated that abiogenesis may have occurred more than once, "merging" independently into the earliest archaeobacteria. Nimur (talk) 14:40, 25 July 2011 (UTC)

Much as the mitochondria in each of our cells seems to have started out as a separate organism. See Mitochondria#Origin. StuRat (talk) 15:30, 25 July 2011 (UTC)

Also, the molecules essential for life evolved from basic molecules long before single cell organisms arose. In a NGC documentary, it was mentioned that some scientists are looking into the possibility that complex molecules evolved from simple molecules inside comets. The idea is that to get complex molecules from simple molecules before you have the protective cell environment that contains all the other enzymes that keeps everything stable, requires low temperatures that prevents thermal equilibrium from being reached.

There are then chemical reactions between molecules that happen to be very close to each other, driven by exposure to cosmic rays and X rays, but the molecules cannot move around to react with other molecules that are further away, and that allows the creation of very unstable molecules, some of which may happen to be a part of some molecule essential for life.

When the comet is kicked out of its orbit in the Oort cloud, it periodically comes closer to the Sun. When part of the comet melts, some of the unstable molecules are able to move around, most will react to form simple compounds like methane and H2O, or simply disintegrate, but by accident some very unstable molecules will combine to form more stable larger molecules. When the comet moves away from the Sun, that will then limit the reactions to between neighbors only, but now these also involve the larger molecules that are the most stable combination of two or more molecules that were cooked up the previous time.

After millions of years, the very complex molecules essential for life can be build up step by step this way. Count Iblis (talk) 15:10, 25 July 2011 (UTC)

You may also be interested in epigenetics and viral fossil. ~AH1 ^(discuss!) 15:45, 25 July 2011 (UTC)

The idea that all current life descends from a single cell does not imply that that cell was the only organism alive at the time or that abiogenesis happened only once. It only means that all other past life forms from different lineages possible different abiogenesis events are losers and have become extinct, unable to compete with the single remaining life lineage. Dauto (talk) 16:20, 25 July 2011 (UTC)

To put it another way - even if all life on earth is descended from one single-celled organism, it doesn't mean that was the only organism that was alive at the time. thx1138 (talk) 16:34, 25 July 2011 (UTC)

In the above discussion at present, "cell" could be replaced in many instances by "molecule" and it would be just as valid. The fact that modern cells are symbiotic with the mitochondria they contain suggests that life did not descend from a single cell, and by analogy I think it much more likely that it didn't descend from a single molecule either. Complex organic molecules, some with the properties necessary for self-replication, including long polymers, many of the nucleotides and amino acids, occur naturally when the atmosphere of the pre-biotic Earth from the fossil record is exposed to lightning. Please see Miller–Urey experiment. 99.2.148.119 (talk) 17:55, 25 July 2011 (UTC)

The OP is correct that the chance of survival of the earliest life form is very small. We can only observe that the Universe is VERY BIG, maybe infinitely so, so that somewhere sometime even the most unlikely circumstances will arise. We don't know in how many places at how many times life has arisen, only that it arose here on Earth. Our conclusions must be that 1) we need to take care of the full diversity of living things on Earth because they are unique and irreplaceable, and 2) looking for signs of extraterrestrial life is not a hopeless quest. Cuddlyable3 (talk) 18:28, 25 July 2011 (UTC)

Similarly, almost all humans are the result of millions of possible sperm and thousands of possible eggs, so the likelihood that their particular genome would have resulted in a person was very small before it actually happened. 99.2.148.119 (talk) 19:17, 25 July 2011 (UTC)

The replicating-molecule first theory is deeply flawed. Lipids mixed with water spontaneously form miscelles (think bubble) which spontaneously split when they have grown large enough. For the cellular metabolism first theory see Stuart Kauffman. μηδείς (talk) 19:22, 25 July 2011 (UTC)

I agree lipids and many other kinds of molecules must have been involved in the first cell. This is an excellent illustrated explanation. We may never know if there was only one first cell by any particular definition, but there were certainly an abundance of protocells. 99.2.148.119 (talk) 21:00, 25 July 2011 (UTC)

Kaufmann's point is that the cell membrane preceded the existence of DNA or RNA, that boundedness precedes replication. I would oversimplify the membrane-first theory as saying that soap bubbles, oil blebs, or sea foam stirred by waves grow and divide spontaneously. The ancient oceans were full enough of complex molecules that once some of these bubbles had a set of molecules (Again, see Stuart Kauffman's Origins of Order) which gave them an advantage at replicating and absorbing more such molecules across their membranes. Kauffman speaks of the primacy of the metabolistic systems. Basically, if the question interests you and you want to say anything on the subject of the origin of life that is not totally naive you have to read him. μηδείς (talk) 21:27, 25 July 2011 (UTC)

Personally I am fond of the idea that life could have existed as an open meshwork of RNA strands carrying all of the constituents of metabolism as covalently bound functional groups; while the soap bubble idea seems facile I just am too skeptical that RNA could effectively regulate an intact membrane before peptides (NRPS) were invented. I prefer the idea that proteins could have evolved as directly processed RNA strands - the biosynthesis of histidine from PRPP (not in Wikipedia as of yet) provides a model. So I like to think of cells as the massively evolved products that result long after biofilms of RNA have surrounded themselves with proteins and crude "cuticles" of phospholipids protecting the surfaces on which they lie. But this isn't an established model, and I don't know if we can ever know what happened really. Wnt (talk) 18:31, 26 July 2011 (UTC)

Aquarium filters

how does filters in fish aquariums work how does they provide oxygen in the tank ..i want a scientific answer i mean all the processes that takes place in it (osmosis, etc) — Preceding unsigned comment added by 175.110.58.208 (talk) 16:44, 25 July 2011 (UTC)

I don't think filters do provide oxygen. That's done by bubbling air through the water. The filter removes things from the water, it doesn't add things. StuRat (talk) 16:50, 25 July 2011 (UTC)

For the filters, see activated carbon and biological filter. ~AH1 ^(discuss!) 16:54, 25 July 2011 (UTC)

Also note that for a small enough aquarium, say a goldfish bowl, enough oxygen is absorbed from the air at the surface (goldfish are also more tolerant of low oxygen levels). For larger aquariums, bubbling air through the water increases the surface area of the contact, and this allows more oxygen to be absorbed. StuRat (talk) 17:09, 25 July 2011 (UTC)

The goldfish has a special trick to survice in bowls. It's called the Labyrinth organ, which allow the goldfish to get oxygen by gulping air. The oxygen in the bowl itself may not be sufficient. EverGreg (talk) 22:46, 25 July 2011 (UTC)

There are different types of filters most use activated carbon or artificial fibers or some combination. These are usually driven by an air pump which has the side effect of releasing bubbles in the water or a water pump which aids in mixing enough to aerate the water. There is no direct connection between the filtering action of the fibers or carbon and the aeration itself. μηδείς (talk) 19:31, 25 July 2011 (UTC)

The main function of the aquarium filter is not to provide oxygen. The sponge-like filters provide a surface for beneficial bacteria that break down waste products (fish poo) in the aquarium water. The pump is there to help oxygen-rich water and waste circulate through the filters, but by creating movement in the water, the pump also help oxygen being exchanged with the air above the water surface. Depending on pH, the waste result in Ammonia (NH3) in the water, which bacteria will break down into poisonous nitrite. The filter bacteria neutralize the nitrite by furter transforming it to nitrate, which is less poisonous. The nitrate may subsequently become nutrition for plants and algae in the aquarium. (And some fish eat algae, setting up a simple but fascinating eco-system) Without a filter, fish in a typical aquarium will suffer poisoning after a couple of weeks. EverGreg (talk) 22:40, 25 July 2011 (UTC)

Lead screws

Lead screws for machines are normally made by lathe. But how was the lead screw for the first lathe made?--78.148.137.217 (talk) 18:29, 25 July 2011 (UTC)

Various methods, including manual methods, for making screw threads are discussed at the threading (manufacturing) article. -- Finlay McWalter ☻ Talk 18:35, 25 July 2011 (UTC)

See machine tools. μηδείς (talk) 21:28, 25 July 2011 (UTC)

One of the best links for answering your question is Screw-cutting lathe > History. It all started out with hand-whittled and hand-filed shapes, and progressed from there, gradually increasing accuracy and precision, in bootstrapping fashion (using one iteration to make future iterations, and finding clever ways to detect and reduce the error along the way). After reading that link, you may wonder how it is that they moved from fairly accurate to extremely accurate screw leads. I don't think Wikipedia has good coverage yet of the answers to that, but the answers involve things like using dividing engines to make high-accuracy gears, which were then arranged into gear trains, yielding precise gear ratios. These, combined with rack and pinion setups and slide rests, allowed them to cut ever-more-accurate leadscrews and build ever-more-accurate lathes (bootstrapping upward). The pinion gear pitch could be accurately controlled with linear measurements and careful filing with magnifying glasses, etc; and the flatness of the slide rests could be controlled with the three-plate method of generating flat surfaces [see Joseph Whitworth]). All of this evolved into metrology, which later also incorporated optics, electronics, and other technologies. — ¾-10 22:59, 25 July 2011 (UTC)

Interesting answer, but I dont see how accuracy can be 'bootstrapped' upward: how does it work? What I can believe is that faily accurate lead screws could have been made using an accurate rack and pinion system which could be made by hand. Thats my opinion anyway.

--GearCutter (talk) 12:02, 26 July 2011 (UTC)

virtual particles.

In simple terms do virtual particles pop into existence in a vacuum because of an energy field?

If there was a vacuum and no field would there be no particles? (or is it not possible to have a vacuum with no energy field?) — Preceding unsigned comment added by 92.23.138.8 (talk) 19:47, 25 July 2011 (UTC)

The existance of anything at all creates a field. Imagine if, in the entire universe, there existed a single electron. That electron has now created an electric field which extends to infinity in all dimensions of spacetime. It would be impossible to suppose a universe in which anything at all existed, but which did not have any fields. --Jayron32 19:58, 25 July 2011 (UTC)

Yes. However in quantum field theory, even the minimum-energy vacuum state gives rise to virtual particles. Looie496 (talk) 21:13, 25 July 2011 (UTC)

In simple terms, the answer is no, there is no such a thing as an energy field. Dauto (talk) 21:31, 25 July 2011 (UTC)

So Gravitational fields , electric/magnetic fields are not energy fields? Are they not fields that store energy? — Preceding unsigned comment added by 92.23.138.8 (talk) 21:49, 25 July 2011 (UTC)

Technically they are force fields, but they don't store force, they transmit it. Sadly "force field" has been so overused in science fiction that I doubt anyone can think of that phrase without imagining an invisible barrier that lights up when things collide with it. 99.2.148.119 (talk) 22:38, 25 July 2011 (UTC)

No physicist calls them energy fields. They are simply called fields. Those "force" fields will have virtual particles but so will the "matter" fields such as the electron field for instance. Dauto (talk) 01:28, 26 July 2011 (UTC)

Sleep of the ancients (and the not so ancient)

While having a discussion about family history, my father noted that my grandparents would not sleep through the entire night. They would go to bed a few hours after sundown, and they would always wake up at around 1 or 2-ish in the morning for a short "break from sleep" (as it where) to have a chat, do some busywork, etc , then go back to sleep until sunrise. My father guessed that it was because my grandparents lived in a very rural part of China (i.e. there is no electricity or modern lighting for miles). Is this sleep pattern widespread? and why don't we do it anymore? — Preceding unsigned comment added by 99.254.130.157 (talk) 21:41, 25 July 2011 (UTC)

If I had to guess, I would say that interrupted sleep in two 3-4 hour naps per day is about as common as shift work. It is all what you are used to, and with modern air conditioning, it's often just as comfortable to stay up late. 99.2.148.119 (talk) 22:42, 25 July 2011 (UTC)

Here is an NY Times article on sleep where they discuss the two sleep pattern. - Akamad (talk) 01:29, 26 July 2011 (UTC)

This is covered in segmented sleep. Personally I find this interesting, because even though I usually don't take a break from sleep, there are differences between the first few hours and the rest - for example, the first part seems deeper, dreamless, less voluntary, more affected by diet, and can proceed despite noise (such as a television); when awakened it feels disorienting, as if my "center of consciousness" has descended. Dreams seem reserved for the light, semi-waking second part. It makes me wonder if the two periods of sleep are really fundamentally different, with different purposes. The article Sleep shows something somewhat akin to this, with more N3 and N4 sleep early on, but minus such extravagant claims. Wnt (talk) 04:27, 26 July 2011 (UTC)

A quick scan of the literature on Geriatric sleep patterns confirms what I thought I'd heard a few years ago: we don't need as much sleep as we get older as we did when we were younger. As an aside, my own grandparents (both have been dead now for over 30 years and were in their late 80s when they died) never slept well at night: I put that down to the fact that my grandmother was a florist and had to be at the market at 5 am to choose the day's flowers, and my grandfather worked in demolition and had early starts there. That's what made me curious as to whether it was just them, or a wider spread phenomenon. It seems to be the latter. --TammyMoet (talk) 09:09, 26 July 2011 (UTC)

Polyphasic sleep also discusses the "ancestral sleep state". ~AH1 ^(discuss!) 00:41, 29 July 2011 (UTC)

I have the privelidge of being able to get up or go to bed whenever I want, and I've also noticed my sleep often falling into two parts with waking in the middle. Perhaps this is what humans evolved to do naturally, or perhaps it is over-sleeping. 92.29.124.70 (talk) 13:21, 30 July 2011 (UTC)

O₄^2-

If the O^2- ion is called the oxide ion, the O₂^2- ion is called the peroxide ion, and the O₃^2- ion is called the ozonide ion, what is the O₄^2- ion called? And what about the O₅^2- and O₆^2- ions? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 22:22, 25 July 2011 (UTC)

I am not sure such species exist. How would O₆^2- be bound? 99.2.148.119 (talk) 22:58, 25 July 2011 (UTC)

It would be a chain of six oxygen ions connected by single bonds, with those at the ends carrying one negative charge each (^-O-O-O-O-O-O^-). Whoop whoop pull up ^{Bitching Betty | Averted crashes} 23:11, 25 July 2011 (UTC)

Wouldn't that decompose into O₂ + 2O₂^-? 99.2.148.119 (talk) 00:11, 26 July 2011 (UTC)

you mean 2 O₂ + O₂^2-? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 00:30, 26 July 2011 (UTC)

Either or both. You'd have to put them together to find out, and that might not be possible. If such species were stable, even at cryogenic temperatures, it should be possible to find something about them. If you can find a university chemistry library, they might have something on oxygen that reviews the attempt to synthesize or stabilize the more exotic species. 99.2.148.119 (talk) 01:48, 26 July 2011 (UTC)

do they really exist? are they stable?--Irrational number (talk) 23:36, 25 July 2011 (UTC)

I'm not sure they do. Someone would have to work out the molecular orbitals on such species, but I think they would have a bond order of zero, which is pretty much the definition of "doesn't exist". --Jayron32 00:04, 26 July 2011 (UTC)

I think it should exist if there is a way to make it. Have a look at trioxidane. I would call O²⁻
₄: tetraoxidane-1,4-diide, or if you would like to omit the 1,4 and render them implicit, then just a basic tetraoxidanediide will do. That is, if you prefer substitutive nomenclature, there is no traditional name for this ion, and I don't know the additive name for it. Oh, and O²⁻
₃ is not the ozonide ion, O⁻
₃ is. Plasmic Physics (talk) 00:32, 26 July 2011 (UTC)

Then what is O₃^2-? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 00:35, 26 July 2011 (UTC)

Trioxidane-1,3-diide or trioxidanediide, it has no traditional name either. Plasmic Physics (talk) 00:48, 26 July 2011 (UTC)

The trioxidane (HOOOH) article says this compound is also called "hydrogen trioxide", so the parent O²⁻
₃ would be "trioxide" according to the pattern "HOOH is hydrogen peroxide and O²⁻
₂ is the peroxide ion". There are articles that talk about HOOOO• as the "hydrogen tetraoxide radical" and HOOOOH as "hydrogen tetraoxide". DMacks (talk) 01:09, 26 July 2011 (UTC)

The problem is, that they use compositional nomenclature to name these compounds, which does not convey any structural information. I think the additive name for O²⁻
₃ could be trioxygenate(2 O—O)(2-). Plasmic Physics (talk) 01:31, 26 July 2011 (UTC)

Likewise, O²⁻
₄ could be called: tetraoxygenate(3 O—O)(2-). Plasmic Physics (talk) 02:52, 26 July 2011 (UTC)

Indeed. However, I'm saying what is being used to identify them in the scientific literature:) There certainly are other possible connectivities, especially for higher numbers of oxygen atoms, but it appears that the simple ___oxide refers to the linear one and that other names are used for other structural isomers (just like "hexane" could refer to any C6H14, but it also specifically refers to the linear one). For example, the literature for H-O(O)-O-H (oxygen-centered analog of sulfurous acid) is identified as "ozonic acid". DMacks (talk) 14:17, 26 July 2011 (UTC)

Correction: ozonic acid is H-O-O(O)-O-H (left out an oxygen in preceding comment). DMacks (talk) 21:01, 26 July 2011 (UTC)

Of course, but he was asking the the name of the deprotonated dianion of dihydrogen trioxide. Plasmic Physics (talk) 15:33, 26 July 2011 (UTC)

I have no idea what you're talking about. I answered each asked case based on literature and actual use (rather than academic follow-the-rules alone--nothing wrong with it, except it's purely academic) and they disprove your concern about compositional naming and instead support the names that do not use the connective rules. My response about 4 was indented as a response to your comment about 4, and my comment about 3 (with extension to 4) was indented as a response to your comment about 3. Even if you aren't using normal indenting schemes, my comments follow each preceding one on the same number. As you broadened the topic (or at least raised new concerns), I responded to each in turn. DMacks (talk) 21:01, 26 July 2011 (UTC)

What I meant, is that you are talking about the names for the neutral molecules, when he was asking about the fully deprotonated anions. I just clarified that if you use compositional naming for the neutral molecule, you can't get the name of the anion just by removing terms from the name. How about dicarbon hexachloride, is there such a thing as the hexachloride ion? I don't thinks so! Plasmic Physics (talk) 23:28, 26 July 2011 (UTC)

Except that terms like 'trioxide' also describe the anion itself. Dihyrdogen trioxide is not merely named because it has three oxygens, it also has the three oxygens which behave as a unit. Hexachloroethane doesn't have that arangement physically. There are other names which could be used analogously to the "trioxide anion", consider the Dihydrogen cation, the Trihydrogen cation, the various names of the Mercury polycations, etc. There is precedence in usage for these terms. --Jayron32 02:16, 27 July 2011 (UTC)

Organic ozonides

If organic peroxides such as acetone peroxide are explosives, then are the even-more-reactive organic ozonides such as molozonide explosive? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 22:26, 25 July 2011 (UTC)

It probably depends a LOT on the identity of the "R" groups. Usually, molozonides are not isolatable products, but rather exist as metastable intermediates as part of larger mechanisms, for example ozonolysis. That is, you don't ever have a bottle of molozonides sitting on a shelf; they exist primarily in miniscule trace amounts during larger synthetic mechanisms. --Jayron32 00:01, 26 July 2011 (UTC)

If you could somehow suddenly isolate a bottlefull of pure molozonides, would it decompose explosively? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 00:37, 26 July 2011 (UTC)

By what mechanism would you isolate it? --Jayron32 00:41, 26 July 2011 (UTC)

I dunno, what I meant is, if somehow a bottleful of pure molozonides came into existance, would it decompose explosively? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 00:43, 26 July 2011 (UTC)

So you've invented a world full of magic whereby bottles of compounds can "pop" into existance without mechanism or cause? Its your magic world, perhaps you can decide whether it would be explosive or not... --Jayron32 00:46, 26 July 2011 (UTC)

Nononononononononono. I meant, does their decomposition have enough power per molecule that it would be explosive if it were ramped up to the scale of a bottle-ful? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 00:49, 26 July 2011 (UTC)

I'll stop being flippant about this. The deal is, if the substance has not been isolated, there exists no empirical evidence as to its properties in this regard. The amount of energy evolved in decomposition is not the sole determining factor in deciding if it explodes. Indeed, the actual amount of that energy can be trivially approximated using basic thermodynamics. However, that number means nothing if the energy is released slowly. You would need to know kinetic information about the decomposition reaction, that is how fast it decomposes. After all, thermodynamically the reaction we call rusting is fundementally, in nearly every way, identical to the reaction we call burning. The difference is that rusting is very slow, while burning is very fast. The same deal here; deciding how much it will explode would actually require a kinetic study of the mechanism, and you would actually need to isolate the compound to do that study. --Jayron32 01:02, 26 July 2011 (UTC)

Are there any isolatable organic ozonides that could be used as explosives? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 13:39, 26 July 2011 (UTC)

Probably not. Per this abstract, ozonides have a "finite lifetime", i.e. they cannot be isolated and stored. In other words, though they form as real intermediates during the process of ozonolysis, you can't "stop" the process and exctract them from the reaction system. --Jayron32 16:26, 26 July 2011 (UTC)

Okay, so the primary ozonides (1,2,3,-trioxolanes) are nonisolatable. What about the so-called secondary ozonides (1,2,4,-trioxolanes?) Whoop whoop pull up ^{Bitching Betty | Averted crashes} 21:16, 26 July 2011 (UTC)

doi:10.1002/ciuz.19730070303 and doi:10.1002/hlca.200490186 do not point out that they are very explosive.--Stone (talk) 21:28, 26 July 2011 (UTC)

But others do (doi:10.1016/j.tet.2006.08.092 and Org Syn Coll 7 p168). There have been some industrial and academic accidents resulting from incomplete "whatever the next reaction is" when that product is isolated. However, some with large substituents are extremely stable. Things that look like they came from cyclohexylidine-cyclohexane and beyond are well studied and even have some biochemical/pharmacological properties. Interestingly the ones that are stable are often not formed by ozonolysis of the seeming parent alkene. DMacks (talk) 21:47, 26 July 2011 (UTC)

That actually makes perfect sense. Peroxides and ozonides are essentially both highly electronegative AND highly electron deficient, which is why they are so unstable, so the presence of electron-donating groups like large, bulky alkyl groups should have a stabilizing effect on their decomoposition. --Jayron32 02:05, 27 July 2011 (UTC)

July 26

Penile exsanguination

Can traumatic amputation of the penis really cause someone to bleed to death? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 00:31, 26 July 2011 (UTC)

What would cause you to suppose that it wouldn't be possible? --Jayron32 00:42, 26 July 2011 (UTC)

I've seen sources pointing both ways, but none are in any way reliable sources. And I meant under normal circumstances. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 00:44, 26 July 2011 (UTC)

I firmly disagree that any circumstances involving traumatic amputation of the penis should be considered 'normal'. TenOfAllTrades(talk) 00:49, 26 July 2011 (UTC)

What I meant was, if you cut the penis off of an avergae man, would he bleed to death without medical intervention? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 00:50, 26 July 2011 (UTC)

Define "medical intervention". If you've got a man, tied up, hanging in such a way as to maximize blood flow out of the wound, and restricted in such a way that he cannot even stop the wound himself, and you sever his penis, would it be impossible for him to die from the wound? I don't see why not. It may not be guaranteed he would die, but it also may not be guaranteed he would survive. It would be a possibility he could bleed out. You could open a similarly sized wound in a part of the body with similar blood flow and cause a similar amount of blood loss. Still, if you've got a man tied up and you are removing his penis in this manner, I'm not sure his general well-being is of primary concern for you. --Jayron32 01:10, 26 July 2011 (UTC)

You hear all those stories in the news, a recent one where the wife ran it through the garbage disposer, and none of them say the man bled to death. μηδείς (talk) 00:56, 26 July 2011 (UTC)

Definitely. You only have to Google penis and "bled to death". As one website puts it, "There is some pretty serious veinage in the penis area." Wikipedia predictably has a list of cases of penis removal.--Shantavira|^{feed me} 07:17, 26 July 2011 (UTC)

I guess the stories ending in death aren't that newsworthy...lol...i think. μηδείς (talk) 09:18, 26 July 2011 (UTC)

More likely to do with the fact most men are going to seek medical attention even if what was cut of has been destroyed by the garbage disposer. Edit: Actually it appears the better answer is you are mistaken about there being no cases in the news where the victim bled to death since our article linked to above mentions several cases where it did happen (one was stabbed as well but this isn't mentioned for the rest). Also in the garbage disposal case the perpetrator herself called the authorities. Nil Einne (talk) 10:12, 26 July 2011 (UTC)

"In January, 1994, Taichung, Taiwan, Chien Liu-liang, age 51, cut off Yao Kuan-jung's penis with scissors, and threw it into the toilet after learning of his affairs. Yao bled to death." Don't know if that's typical without stitches/reattachment though... Whoop whoop pull up ^{Bitching Betty | Averted crashes} 13:17, 26 July 2011 (UTC)

There is an unpleasant picture (I am not inclined to give the link) of a piglet that died of a prolapse after a farmer's clumsy castration (of the pig, not the farmer). Sight of the picture might cause everyone to vomit "Whoop whoop". Cuddlyable3 (talk) 22:37, 26 July 2011 (UTC)

And then there's Detachable Penis. which we have an article on. Bus stop (talk) 22:47, 26 July 2011 (UTC)

I woke up this morning with a bad hangover, and my penis was missing again...--Jayron32 16:31, 27 July 2011 (UTC)

Theoretically ANY injury could result in exsanguination, but I've never seen a reliable source say it was likely. There is a lot of venous drainage but it doesn't have the incoming bloodflow of, say, a major artery. Does it happen? obviously it does. Then again I noticed watching TV that Mythbusters is full of those "damn unlucky" where they test it and test it and it should be impossible but a handful of verifiable cases exist. I would judge this one, "obviously happens, but I don't think it's as likely or common as the internet would tell you" HominidMachinae (talk) 05:51, 30 July 2011 (UTC)

That list shows a remarkable preponderance for China & south-east Asia. Axl ¤ [Talk] 07:57, 30 July 2011 (UTC)

Preference for extreme versions of traits in evolution

I'm trying to remember the name of a particular concept in the theory of evolution. I read about this many years ago but can no longer find any reference to it. It's something like this: if an animal has evolved to look for something that has certain traits, what it will actually look for and prefer is the essentials of that percept, so that the particular measurements don't matter, and it will just want more of the essentials regardless of whether such a thing would actually ever be found in reality. The example I remember had to do with sheep preferring to follow a fake sheep's bottom over a real one because the fake one had more contrast, and therefore, to the sheep, was more "sheep bottom-ish". Another example would be the minimalistic style of cartoon characters such as Mickey Mouse with large, expressive eyes that convey emotions quickly. Does anyone know what I'm talking about? --✶♏✶ 00:34, 26 July 2011 (UTC)

If the selection is for one extreme version, it's called "directional selection." If it's for both extreme versions, it's called "disruptive selection." Whoop whoop pull up ^{Bitching Betty | Averted crashes} 00:39, 26 July 2011 (UTC)

See Fisherian runaway. --Jayron32 00:45, 26 July 2011 (UTC)

Sounds like you are after Supernormal Stimuli ?Vespine (talk) 01:11, 26 July 2011 (UTC)

YES. That is exactly it, Vespine. Thank you.

Resolved

--✶♏✶ 01:47, 26 July 2011 (UTC)

Metals in gas form

Other than mercury vapour, are there any other common metals-as-gas? 207.81.30.213 (talk) 06:22, 26 July 2011 (UTC)

All metals can exist in the gas phase. Plasmic Physics (talk) 07:14, 26 July 2011 (UTC)

What does gaseous mercury look like, say at atmospheric pressure? Is it just a transparent gas? Or does it have a colour? Graeme Bartlett (talk) 09:06, 26 July 2011 (UTC)

According to our article, mercury is a liquid between -38°C and +357°C so it is not a "common metal-as-gas". List of elements#List seems to indicate that mercury is indeed the metal with the lowest boiling point at standard pressure, 630 K (357 °C; 674 °F), though that list doesn't include the boiling points of the artificially-created heavy elements (atomic number > 98) which have such short half-lives it is impossible to measure many of their physical properties. Astronaut (talk) 14:02, 26 July 2011 (UTC)

Wouldn't einsteinium (element 99) and fermium (element 100), which have long enough half-lives to be isolatable in macroscopic quantities, have therefore long enough half-lives to measure their physical properties? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 14:13, 26 July 2011 (UTC)ko

Considering, we don't have images of macroscopic quantites, I doubt it. Plasmic Physics (talk) 15:18, 26 July 2011 (UTC)

Uh,

? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 16:01, 26 July 2011 (UTC)

Marvelous! μηδείς (talk) 20:20, 26 July 2011 (UTC)

Good one einstein, it's not Einsteinium metal, it's a compound of it in solution. Plasmic Physics (talk) 23:18, 26 July 2011 (UTC)

"Quartz vial (9 mm diameter) containing ~300 micrograms of Es-253 solid." I now have serious doubts about your statement. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 10:18, 27 July 2011 (UTC)

OK, statement withdrawn. Plasmic Physics (talk) 06:44, 28 July 2011 (UTC)

By some definitions, hydrogen is a metal when you get it in the solid state, so one could say that at room temperature it is a gaseous metal. The problem is, by definition, a metal has to be solid or liquid; you can't get the "cloud" behavior of electrons when the material is in a gaseous state (as far as I know, someone please correct me if I'm wrong), which is the defining characteristic of a metal.-RunningOnBrains^(talk) 23:35, 26 July 2011 (UTC)

Read the article you linked - hydrogen is only a metal under extremely high pressures. Icek (talk) 11:15, 27 July 2011 (UTC)

Yes, thank you I forgot to point that out. My example was meant to be slightly absurd anyway. My argument about the inability of gasses to be metallic still stands (although I am curious about the implications if I am wrong). -RunningOnBrains^(talk) 15:38, 27 July 2011 (UTC)

Runningonbrains is essentially correct here. For all intents and purposes, the defining characteristic of metals is metallic bonding; gases by definition are unbound, so cannot be metals. You can have elements from the so-called "metallic" regions of the periodic table which are in the gas phase; for example you can have, say, gas phase mercury molecules. However, that is gas phase mercury, and not a metal. --Jayron32 16:30, 27 July 2011 (UTC)

Thanks. That makes sense now. My question is now, are there any gaseous compounds that are common or familiar that contain these "metallics"? 207.81.30.213 (talk) 05:23, 28 July 2011 (UTC)

You mean gaseous at room temperature and standard pressure? I can't think of any. There are some with semimetals or metalloids — see arsine and silane. --Trovatore (talk) 05:58, 28 July 2011 (UTC)

UF₆ is the lowest-boiling/sublimating-temperature compound at 1 atm I can think of that has a "definitely metal atom" in it. OsO₄ is not a low-boiling compound, but it does readily sublime at room conditions (it's usually supplied in solutions of known concentration so one does not need to handle the pure material). Whether these are "common" (or especially "familiar") is a matter of opinion:) DMacks (talk) 06:11, 28 July 2011 (UTC)

Taking a cue from UF₆, turns out that several other metal hexafluorides are low-boiling materials. DMacks (talk) 07:01, 28 July 2011 (UTC)

Another point to make, all substances have vapour pressures in the solid state, even tungsten metal. Given a couple million years, one miligram of tungsten should completely sublime. Plasmic Physics (talk) 06:41, 28 July 2011 (UTC)

That depends on the surface area (not the vapor pressure, but the time). How did calculate or where did you look up the couple million years? Icek (talk) 15:47, 29 July 2011 (UTC)

It's a guess, assuming the piece of tungsten is spherical, and the sublimation rate is constant, and a non-equilibrium. Plasmic Physics (talk) 00:24, 31 July 2011 (UTC)

formula of separation

Is there a formula, which relates or connects (or separates) the mass/energy ratio of each subatomic particle so far found hiding in the nucleus of an atom? --DeeperQA (talk) 07:01, 26 July 2011 (UTC)

There are obviously experimental values for particle masses, but I don't think there is a theoretical formula that does what you want. In the Standard Model of particle physics, the masses of the elementary particles are input parameters, so the model takes them as given and does not attempt to explain them or derive them from other parameters. If we knew more about the Higgs boson then we might find a deeper connection between these mass values. Gandalf61 (talk) 09:40, 26 July 2011 (UTC)

How about an approximation formula like the one that relates the orbits of the planets? --DeeperQA (talk) 13:24, 26 July 2011 (UTC)

No simple formula exists. Models beyond the standard model such as grand unified theory, supersymmetry, and technicolor often provide frameworks where relationships between the masses of different particles do arise, but the relationships are complex, involving solutions of differential equations. They are not simple algebraic relationships. Dauto (talk) 14:18, 26 July 2011 (UTC)

How about weight coefficients from neural networking? --DeeperQA (talk) 14:57, 26 July 2011 (UTC)

What about them? Dauto (talk) 16:05, 26 July 2011 (UTC)

Surely there is a neural networking model of subatomic particle mass and energy relations compared with other particles. --DeeperQA (talk) —Preceding undated comment added 23:36, 26 July 2011 (UTC).

I never heard of one. Dauto (talk) 19:46, 27 July 2011 (UTC)

Technicolor?! Whoop whoop pull up ^{Bitching Betty | Averted crashes} 14:42, 26 July 2011 (UTC)

Dauto meant Technicolor (physics). Deor (talk) 15:47, 26 July 2011 (UTC)

Oh. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 15:59, 26 July 2011 (UTC)

Yes, indeed. thanks for pointing that out. I had the link fixed. Dauto (talk) 16:04, 26 July 2011 (UTC)

While they don't hide in the nucleus, the masses of the charged leptons obey the Koide formula. Icek (talk) 11:18, 27 July 2011 (UTC)

That's interesting. Dauto (talk)

See also the recently-confirmed CPT symmetry. ~AH1 ^(discuss!) 00:09, 29 July 2011 (UTC)

massaging muscles

I don't understand the difference between chiropractic & osteopathy.--74.176.42.52 (talk) 13:09, 26 July 2011 (UTC)

Your IP is American, so let me give an American answer. In the US, American osteopathy is practiced by fully licensed physicians (known as a doctor of osteopathy or DO), with similar training and equal rights to the better known medical doctors (i.e. MDs). Such individuals have the training to recognize a wide variety of ailments and respond appropriately, including with medication or surgery. A chiropractor, in the US, will have less training than an MD or DO, and generally is not permitted to write prescriptions or perform surgery. Their practice focuses on the manual manipulation of the musculoskeletal system, sometimes with the aid of advanced imaging technology. In many ways their background and training is more similar to focused professional degree like dentistry. Modern reviews have found chiropractors to be effective in the elimination or management of some forms of mild to moderate skeletal pain, but chiropractors are unqualified to diagnose and treat more severe ailments, the way that a DO might.

It is important to note that in many parts of the world, "osteopath" refers to a profession that is more akin to a chiropractor, with more limited training and fewer rights. However, in the American system only fully licensed DOs are legally allowed to use the term. Dragons flight (talk) 13:47, 26 July 2011 (UTC)

Clone armies

Would it be possible or practical to clone a person many times to create a clone army as in Star Wars Episode II: Attack of the Clones? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 13:37, 26 July 2011 (UTC)

Are there any known technologies for speeding up human growth? If not, I don't see how cloning would be any easier then just breeding an army (as long as your evil overlord isn't concerned with ethics). Googlemeister (talk) 13:41, 26 July 2011 (UTC)

It would bypass all the inconvienences of (not) having sex. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 13:59, 26 July 2011 (UTC)

Possible? Maybe in a couple decades. Practical? Unlikely. They're all going to be babies from the get-go, so you'd need a whole hell of a lot of infrastructure to raise them to adulthood. Much easier to just recruit pre-raised civilians. Plus, what if the enemy learns that all the clones are allergic to peanuts, or are susceptible to X disease? Also, what if the Jedi learn of these plans? --Goodbye Galaxy (talk) 13:44, 26 July 2011 (UTC)

Star Wars world: Even if they do learn about it, there won't be a hell of a lot they can do about it. Look at how effective the clones were during the Great Jedi Purge. Real world: No problem. Just ignore them Jedi. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 13:54, 26 July 2011 (UTC)

And what if we invent some way to drastically speed up their growth in a decade or two? Then would it be practicla? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 13:55, 26 July 2011 (UTC)

And how would cloning an army bge unethical? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 13:56, 26 July 2011 (UTC)

While ethical standards vary, I suspect most people would agree that humans ought to have the right to determine the course of their own life. Raising someone, clone or not, to be a soldier without giving them any say in the matter would offend the notions of personal freedom that many people consider important. Dragons flight (talk) 14:07, 26 July 2011 (UTC)

Solution: Genetically engineer them to have no free will. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 14:09, 26 July 2011 (UTC)

Many people would consider tampering with free will to also be unethical. Of course if you want to use your clone army to raise an evil empire this is probably not a problem. If you have some more noble goal, then you probably ought to explain why you can't accomplish it with a more conventional army. Dragons flight (talk) 14:19, 26 July 2011 (UTC)

Evil empire! Yay! Whoop whoop pull up ^{Bitching Betty | Averted crashes} 14:34, 26 July 2011 (UTC)

Also I find it unlikely removal of free will is even possible unless you want an army of vegetables. If you're building an army, droids seem much more sensible to me--Jac16888 ^Talk 14:22, 26 July 2011 (UTC)

Droids can't problem solve or improvise. And they can't pick up a weapon off a dead droid and keep fighting with it. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 14:31, 26 July 2011 (UTC)

And what use would be an army of plants? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 14:31, 26 July 2011 (UTC)

And a droid is harder to biuld than a human is to clone and gnetically engineer. And droids have the possibility of being defective. And you have to make an assembly line with all its attendant problems. And you have to keep people from sabotaging the droid factory. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 14:36, 26 July 2011 (UTC)

Whether it is possible (or will be) to build a clone army or not, it's just not practical if you don't have the military hardware. Sure, it might become possible to put some cells in a test tube and leave them for a while to grow into a million or so humans, but a machine gun is not going to replicate itself. You'll just end up with a (possibly huge) unarmed population draining other resources (food & water, clothing, place to stay, etc.), and the cash to pay for the cost of all this could have been 'better' used to advance your current miltary's technology, such as by investing in drone technology or robotics. --KägeTorä - (影虎) (TALK) 14:44, 26 July 2011 (UTC)

So make weapons that grow and replicate themselves. (And blame the Yuuzhan Vong for giving me ideas.) Whoop whoop pull up ^{Bitching Betty | Averted crashes} 14:47, 26 July 2011 (UTC)

That still does not offset the costs. You have to invest cash to:

• develop the technology that allows accelerated cloning;
• develop existing infrastructure to prevent food/water/living space/other resource shortages caused by sudden increase in population;
• develop technology that allows cloning of weapons

Compare this to just investing in existing technology (we already have drones and robotics), you can guess which is cheaper. --KägeTorä - (影虎) (TALK) 15:43, 26 July 2011 (UTC)

But once you have all that, you are going to run out of easily accessible metal a long time before you run out of easily accessible carbon. The carbon is all on the surface or just below it. Metal you have to go deep for. And clones are less likely to be defective than droids, considering the number of defective-electronics-related recalls we've had over the last 20 years (16) and the number of defective-organism-related recalls we've had over the last 20 years (zero.) Whoop whoop pull up ^{Bitching Betty | Averted crashes} 16:17, 26 July 2011 (UTC)

To answer your original question, yes, it is practical, assuming you have a level of technology that can genetically engineer them to age quickly and be compliant but still able to improvise, and can develop organic self replicating weaponry, and you're in a dictatorship so people won't complain its unethical and you have unlimited money and resources.--Jac16888 ^Talk 16:23, 26 July 2011 (UTC)

If you have the tech to build a clone army, I bet you can dig a deep hole. We should also bear in mind that the "energy crisis" is temporary - the Earth's mantle is bursting with energy, the sky is full of it, to those with the tech and a few basic self-fabricating robots there is no problem melting down common feldspar for the aluminum. Also, "robots" can be made out of carbon and be just a few nanometers on a side and do all kinds of obscene damage (or conduct the most subtle surveillance) on persons and machines.

When dealing with humans, why fabricate when you can simply use wild-caught stocks? Do a quick operation, install a prosthetic hippocampus, the poor bastards will be perfectly trained and perfectly loyal. No need to track them down and force them, just use economics ... who the hell is going to employ someone who has to be schooled for twelve years to be a half-trained idiot? (this is the "mark of the beast" described in the Revelation of John, I would venture...) Wnt (talk) 16:33, 26 July 2011 (UTC)

We should distinguish cloning from some sort of "accelerated growth". Cloning is simply a genetic procedure to get (in this case) homogeneous soldiers - maybe this helps if you want to keep your perfect set of enhancements, or copy your favorite military hero, but it has the downside that your whole army has the same vulnerabilities. They might be prone to make the same mistake; more importantly, a bioweapon should be able to exterminate them all quite handily with only "acceptable losses" on the other side which is more genetically variable.

Now accelerated growth is useful if you have for some reason a shortage of meat, but what modern society has a shortage of humans for any purpose? Teeth and fingernails don't win wars; they are a raw contest between capital and capital, with incidental human casualties. True, certain wars like the U.S. is fighting seem to involve "boots on the ground", but not so much wars that people are fighting to win; rather those in which one is trying to "win hearts and minds", i.e. public relations exercises, whether to those abroad or at home. Now war is politics by other means, or more often politics is war by other means, and I suppose a cloned army of suave, handsome spokespersons who can sound supremely trustworthy while lying might sound useful ... but I doubt we have a politician shortage either. Besides, political contests are something of an "evolutionary arms race", with different models winning from one year to the next ... that's a situation where sexual reproduction should do better than cloning. Wnt (talk) 16:24, 26 July 2011 (UTC)

Accelerated growth would be useful if you had extremely high casualties in a long drawn out war of attrition, but unless you wipe their brains at the same time, a clone is not going to be any more pre-disposed to pulling a "Charge of the Light Brigade" then a normally born person. Googlemeister (talk) 19:43, 26 July 2011 (UTC)

After previously receiving the order from Klaatu to destroy the earth, it then transforms itself into a swarm of self-replicating insect-like nanites that begin destroying everything in their path including the military facility. The swarm of nanorobotic locusts consumes everything in its path and is now on a path to destroy humankind heading to Central Park where the major sphere is located.

Count Iblis (talk) 20:14, 26 July 2011 (UTC)

To answer Wnt, you would have to make all those prosthetic hippocampes. To answer Googlemeister, so accelerated growth would be useful in a kind of vastly ramped-up WWI? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 21:11, 26 July 2011 (UTC)

Not really unless you can reprogram their brains to vastly reduce self-preservation drives. A cloned human would not really be all that different then an identical twin. They wouldn't be zombies. Googlemeister (talk) 21:23, 26 July 2011 (UTC)

No, I meant about the "war of attrition" bit. And what was Jac16888 saying a while back about an army of vegetables? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 21:40, 26 July 2011 (UTC)

And about a bioweapon being able to wipe out an entire clone army with only "acceptable" losses on the other, more genetically-variable side, there's an easy solution: Simply genetically engineer them to have super-strong and super-efficient immune systems. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 21:49, 26 July 2011 (UTC)

A simple nuke would do it - and wipe out the facility that creates the clones. Invest in technology, I say! Not masses of meat. --KägeTorä - (影虎) (TALK) 23:15, 26 July 2011 (UTC)

The Sontarans were eventually defeated by the Rutans, were they not? μηδείς (talk) 02:52, 27 July 2011 (UTC)

You would have to keep the thing carrying the nuke from getting shot down (even if it is a ballistic missile—any society capable of creating and accelerating the growth of a clone army and clone weapons is also going to have anti-ballistic missiles.) And remember my words when your entire droid army is disabled by a simple computer virus! Whoop whoop pull up ^{Bitching Betty | Averted crashes} 10:13, 27 July 2011 (UTC)

Any army with nukes, and knowing that the enemy has anti-ballistic missiles, will have (or develop) the ability to counter that - either by developing better nuclear missiles, or by firing swarms of them, or something. Apologies, but this entire conversation has become pointless. You asked of the practicalities, and then when anyone gives you reasons why it may not be practical, you come up with unlimited tech and unlimited resources and unlimited money to create something that counters their argument. Unlimited tech, unlimited resources, and unlimited money do not exist, and so, to answer your questions (and keeping in line with my earlier answers), no, it is not practical, and will never be. --KägeTorä - (影虎) (TALK) 15:34, 27 July 2011 (UTC)

So what was Jac16888 saying a while back about an army of vegetables? What use would be an army of plants? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 10:25, 27 July 2011 (UTC)

"Vegetable" is slang for a brain-dead, or nearly brain-dead human. The implication is that if you take away people's free will, you'll also take away their ability to think for themselves. APL (talk) 22:15, 27 July 2011 (UTC)

I don't know about free will (it's disputed whether it exists anyway), but if you quick-grow "clones", they won't really have much by the way of memory. Though again the hippocampal prosthesis might fix that, alas. Wnt (talk) 18:11, 28 July 2011 (UTC)

Just build a bunch of cyborgs that vomit grey goo. ~AH1 ^(discuss!) 00:05, 29 July 2011 (UTC)

Upper limit on size of atoms

How does the speed of light provide an upper limit to the size of atoms? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 14:15, 26 July 2011 (UTC)

Assuming that by size you do indeed mean size, as oposed to mass, the size of atoms is governed by the Bohr radius which is inversely proportional to the speed of light. Dauto (talk) 14:39, 26 July 2011 (UTC)

Please explain. I don't get it. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 14:45, 26 July 2011 (UTC)

What don't you get? Did you read the linked article? Dauto (talk) 14:52, 26 July 2011 (UTC)

What I don't get is how that limits the size of atoms. I meant how does that limit the number of electrons in an atom as stated in Extended periodic table#End of the periodic table. Would I ask you if I'd read the article and understood it? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 15:04, 26 July 2011 (UTC)

From what I know, it is more accurate to say that there is an upper limit to the size of electrically neutral atoms, and it is has something to do with the speed of the electrons in the lower s orbitals. The bigger the atoms gets the more energy the lower orbitals have, they move faster. I wonder, is relativistic mass compensated for in this theory? Plasmic Physics (talk) 15:15, 26 July 2011 (UTC)

So unless Einstein was wrong, the size of an electrically neutral atom larger than that limit would either force the inner electrons into the atomic nucleus or eject the outer electrons from the atom. Is their an upper limit to the size of ions? Would it be possible for an atomic nucleus to get large enough for its radius to become greater than the range of the nuclear strong force? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 15:20, 26 July 2011 (UTC)

So, as I suspected, by size of an atom you rally didn't mean the size of an atom. What you really mean is the atomic number of the atom. Atoms with extremely large atomic number would have their innermost electrons moving at relativistic speeds which means they must incur an energy penalty in the form of relativistic mass of the electron destabilizing the atom. The physical consequence of that would most likely be that those inner electrons would be absorbed by the nucleus where a proton would be converted to a neutron effectively reducing the atomic number of the atom. We will probability never know for sure since, as you pointed out, large nuclei like those are extremely unstable because their radii is close to the range of the force that keeps the nucleons together. Dauto (talk) 16:00, 26 July 2011 (UTC)

(edit delayed...) I think the speed of light is the wrong answer, sort of. What really matters is the fine structure constant, alpha, which appears in the Bohr radius. The alpha constant has many deep significances, and I'm not sure I truly understand what ratio it represents in a real, relativistic and quantum mechanical atom, but the article says it is "The ratio of the velocity of the electron in the Bohr model of the atom to the speed of light." Now angular momentum is quantized (as with all angular momentum, in units of Planck's constant). You can picture various "planetary orbits" around a nucleus, but the larger the central charge, the closer the electron has to be and the faster it has to travel to end up with the same angular momentum. In an atom beyond 137, the orbit (in Bohr terms) would have to be faster than the speed of light. But relativistic mass should increase the angular momentum by arbitrarily large amounts, so this isn't truly a solid barrier... still, once the relativistic mass is greater than the ionization potential there is no way for the electron to stay there. Wnt (talk) 16:10, 26 July 2011 (UTC)

Yes, and you can also say that the Bohr radius is the electron Compton wavelegth divided by alpha. In natural units, the electron Compton wavelength is 1/m. If I put the speed of light and hbar back, I get: hbar/(m c). Then, the length scale in a nonrelativistic atom shouldn't contain c, and I have the coupling constant alpha vailable which contains an explicit factor of 1/c. Although alpha is still dimensionless, so it actually doesn't depend on c, in non-relativistic physics, we can say that some factors of c are absorbed in the definition of the charge. Anyway, even though it looks stupid from the POV of tradional dimensional analysis, this argument leads to

hbar/(alpha m c) for the Bohr radius. Count Iblis (talk) 18:20, 26 July 2011 (UTC)

Extremely rapid alpha decay would be the most likely fate of these very large atoms. Unless of course, you consider a neutron star an atomic nucleus. ~AH1 ^(discuss!) 00:00, 29 July 2011 (UTC)

Dream induced nausea

I want to make it clear that I'm not seeking diagnosis of any kind.

A while back, I had a bizarre, very real-seeming, dream. Can't remember a single detail about what happened in it, but from time to time something reminds me of it and the whole thing comes flooding back. This causes me to feel very clammy, light-headed, sweaty and nauseous. This lasts from five to ten minutes whilst I "relive" the dream, after which I gradually forget all the details of the dream. I haven't yet had the foresight to write any of the dream down whilst I can remember it.

This happens about once a month or so, and doesn't cause me much alarm. I'm certain there's nothing major wrong with me, but it is awfully baffling. Does anyone have any idea what the hell is going on? Pascal yuiop (talk) 21:14, 26 July 2011 (UTC)

Sounds like the results of a standard nightmare to me. Or, alternatively, perhaps you were nauseous first, and your brain constructed a dream around that feeling, to "explain" it. StuRat (talk) 22:45, 26 July 2011 (UTC)

I'd consider this a medical question. Imagine Reason (talk) 16:43, 27 July 2011 (UTC)

You may want to try voice-recording the details. Just be sure not to immediately jump to an alien abduction conclusion. ~AH1 ^(discuss!) 23:55, 28 July 2011 (UTC)

Nausea is a sort of generic symptom, it can be caused by many, many things. I can't give medical advice, not a doctor, ect. but it may be worth telling a doctor especially if you are frequently vomiting. HominidMachinae (talk) 07:14, 30 July 2011 (UTC)

Neutron degeneracy

Would a neutron-degenerate fluid be considered a gigantic cluster of billions upon billions of nuclei consisting of single neutrons, or would it be considered a gigantic single nucleus consisting of billions upon billions of neutrons? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 21:46, 26 July 2011 (UTC)

The latter is a better description. Dauto (talk) 22:38, 26 July 2011 (UTC)

I would say that neither is a good description. An atomic nucleus is an entity bound by the nuclear force; neutron-degenerate matter is bound by gravity. Free neutrons are not considered nuclei. (Of course, you run into nomenclature problems when describing hydrogen, which when ionized is just a free proton, but one would logically have to call it a hydrogen nucleus). If gravity were somehow removed from neutron-degenerate matter ("magically", as a previous question stated), there would be an enormous release of energy, and the system would no longer be bound. -RunningOnBrains^(talk) 23:51, 26 July 2011 (UTC)

The use of the term "proton" in describing the monatomic cation of hydrogen is 99% of the time used heuristicly; generating actual H¹⁺ cations by simple chemical means is essentially impossible; it requires rather exotic conditions. Under aqueous systems, the ion known as H¹⁺ actually physically exists as covalently bonded polyatomic ions containing various amounts of water molecules (see Hydronium and also Grotthuss mechanism for examples of several of these). In gas phase, hydrogen ions form clusters with neutral hydrogen atoms and molecules as well, for example see the Dihydrogen cation and the Trihydrogen cation. There just does not exist, in any meaningful amounts, any way to form H¹⁺ cations chemically in all but the weirdest, most exotic, situations. --Jayron32 02:01, 27 July 2011 (UTC)

Good point. I was not aware it was so hard to ionize hydrogen (although I should have suspected). I suppose this is part of the reason why proton decay is so hard to observe (assuming it exists)? -RunningOnBrains^(talk) 09:47, 27 July 2011 (UTC)

Free neutrons are nuclei. They are nuclei of neutronium-1. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 10:09, 27 July 2011 (UTC)

No they are not. As you see in that article, neutronium is a fictional substance, or a non-scientific word for neutron-degenerate matter, which does not exist except in very exotic high-gravity situations. Nuclei are bound absent of non-nuclear forces, neutron-degenerate matter is not.-RunningOnBrains^(talk) 15:35, 27 July 2011 (UTC)

You're just stating the obvious here. True, a neutron star is bound by gravity, not the strong force, but its density is very similar to the density of nuclear matter and can be seen as one gigantic nucleus. Is it reeaaaaly a nucleus? That's a matter of semantics. Dauto (talk) 15:56, 27 July 2011 (UTC)

I suppose it's just semantics, and I kind of got on a tangent there, but the point I was trying to make is that free neutrons are not nuclei. Medeis's reasoning below is better than mine. -RunningOnBrains^(talk) 14:20, 28 July 2011 (UTC)

A free neutron is not a nucleus because nuclei are parts of atoms, and electrons do not orbit bare neutrons. But do not lose hope. Free neutrons have a 15 minute half life and Beta decay into a proton, an electron, and an anti-neutrino. μηδείς (talk) 16:20, 27 July 2011 (UTC)

I think what we're getting at here is, does the nuclear force have a significant effect on how a white dwarf behaves? Does it contribute significantly to holding it together as a whole, or does it affect what happens if something slams into the surface? According to nuclear force it applies whether the nucleons are protons or neutrons, and as stated above the density is similar to a nucleus, so I'd think it would ... but I don't know this! Wnt (talk) 18:19, 27 July 2011 (UTC)

That's not how I read the original question. But just in case anybody is still wondering, it is a well known fact that neutron stars are gravitationally bound objects. The strong force by itself wouldn't be able to hold the thing together. Dauto (talk) 19:04, 27 July 2011 (UTC)

I suppose not - is that simply because the neutrons would decay, unless pulled down so hard that they would be forced to recombine? Let's put it this way: does the nuclear force reduce a neutron star's mass roughly as much as it reduces the mass of a nucleus? Wnt (talk) 18:23, 28 July 2011 (UTC)

Human clone and voice

Would a human clone have the same voice pitch as the original?--178.180.6.38 (talk) 22:35, 26 July 2011 (UTC)

It would likely be quite close, barring a disease or injury which changed either one. However, people can choose to speak a bit lower or higher, and do so depending on cultural factors and personal preference, as well as current emotional state. StuRat (talk) 22:40, 26 July 2011 (UTC)

I wonder how much the exposure to all too common endocrine disruptors such as phthalate, bisphenol A, PBDE etc. would have on voice development; maybe a cloned man from a cleaner society would have a deeper voice than the original. OTOH that might just be from all the anabolic steroids he was pumped up with to make him an almighty super soldier... Wnt (talk) 06:42, 27 July 2011 (UTC)

Identical twins are (natural) clones. Roger (talk) 06:53, 27 July 2011 (UTC)

Ew! That's unnatural! μηδείς (talk) 20:57, 27 July 2011 (UTC)

Blood drinking

Is it safe to drink everyone's blood regardless of blood type and Rh, as vampire tales tell? Would there be any complications?--178.180.10.50 (talk) 22:41, 26 July 2011 (UTC)

No. Easy way to catch HIV Pascal yuiop (talk) 22:45, 26 July 2011 (UTC)

No it isn't, otherwise you would also be at risk of getting HIV from oral sex. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 22:57, 26 July 2011 (UTC)

There is a non-zero risk of catching HIV from unprotected oral sex. (CDC Q&A) It is logical to then assume that drinking blood provides an equal, if not greater, risk. -RunningOnBrains^(talk) 23:38, 26 July 2011 (UTC)

Indeed this is of course noted at HIV#Transmission and oral sex#STD risk and I thought was common knowledge. Nil Einne (talk) 07:20, 27 July 2011 (UTC)

I take it back. I'm not an expert - I was actually basing this on a legal case where a guy was stopped from doing a one man solo theatre show because his idea of gaining empathy from the audience was to splash them with his HIV-infected blood. Lawyers don't have the best grasp of medicine. Ignore me! Pascal yuiop (talk) 23:05, 26 July 2011 (UTC)

As noted above, you could contract diseases from contact with blood (not likely, but possible). However, you seemed to be asking about compatibility of blood types. There's no concern there, that would only be a problem if you injected other people's blood into your bloodstream. StuRat (talk) 23:08, 26 July 2011 (UTC)

Blood can be nasty stuff. Ingested blood might allow infection through mucous membranes or through open sores. There are lots of deadly blood-borne diseases, in addition to AIDS. Hepatitis B and C, and viral hemorrhagic fevers, for starters. Then lots of other nasty pathogens not mentioned in the Wikipedia article, such as syphilis, Malaria, Babesiosis, Brucellosis, Leptospirosis, Relapsing fever, Colorado tick fever, and Creutzfeldt-Jakob disease. There's also Human T-lymphotropic virus type I I've even read of various fungi causing serious problems when they contaminated IV lines. Many other illnesses can be transmitted by blood, such as tuberculosis and Dengue fever. The shorter list might be infections which cannot be spread via contaminated blood. (Staph? MRSA? Strep? Pseudomonas? Anthrax? Pneumococcus? Neisseria meningitidis? Clostridium tetani? Legionella? Chlamydia? Yersinia pestis? Mycobacterium leprae? Neisseria gonorrhoeae?) Edison (talk) 03:45, 27 July 2011 (UTC)

Of course, vampires don't usually have much to fear about disease, because they're already dead. ;) Wnt (talk) 06:35, 27 July 2011 (UTC)

The questioner asked "Is it safe to drink everyone's blood.." not "Is it safer for a vampire to drink everyone's blood." Vampire literature often depicts a vampire opening his own blood vessel and having a human drink from it, as well." I did not even add smallpox and rabies to the list of bloodborne pathogens, because it is not likely to be present in the blood of a random human, and the same might be true of many of the other rare pathogens, but various STDs are all too common in the modern human population. But depending on where the vamp wannabe is consuming blood, the donors just might be infected. The claim that pathogens cannot cause infections from oral administration is refuted by oral transmission of STDs, cholera and other diseases. Edison (talk) 14:12, 27 July 2011 (UTC)

And it's only a risk if you have sores. Once the blood reaches the stomach, if it hasn't found any sores before then, any viruses are dead protein, fat, and RNA. And besides, only a hundredth of a percent of the population actually has HIV, and they're likely to know this. It is more likely that your wife will die in childbirth than that you will contract HIV from drinking blood. Ditto for oral sex. It's possible to catch HIV through either of these routes, but in either case the risk is too small to be worth worrying about. :) Whoop whoop pull up ^{Bitching Betty | Averted crashes} 09:59, 27 July 2011 (UTC)

Are you sure about that? There are a number of food-borne viruses. AlmostReadytoFly (talk) 11:23, 27 July 2011 (UTC)

Yes, there are. HIV is not one of them. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 13:12, 27 July 2011 (UTC)

I didn't say it was, I was taking issue with your assertion that "Once the blood reaches the stomach, if it hasn't found any sores before then, any viruses are dead protein, fat, and RNA", given that there are viruses which can survive the stomach. I realise I could have been clearer. AlmostReadytoFly (talk) 13:59, 27 July 2011 (UTC)

By "viruses" I meant "HIV viruses." And I was talking about the extremely great smallness of the risk of contracting HIV through ingestion. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 15:04, 27 July 2011 (UTC)

I don't mean to belittle Whoop, but you are overly-minimizing this risk: 30 million people have HIV, which would be about 1/2 of a percent of people (this isn't just Africa...there are over 1 million cases in the US). Even worse: 170 million people worldwide have Hepatitis C (about 2.5%) which is nasty in its own right. Additionally, even acid reflux (causing damage to the lower esophagus) and ulcers can offer a mechanism of infection beyond mouth sores. It's just not something you want to mess with.

But to answer what I assume is the gist of the original poster's question, yes, it is safe to drink blood that is known to have no diseases, but it will likely make you feel nauseated if you drink to much. If a reliable source is to be believed, you can drink up to a pint without feeling sick.-RunningOnBrains^(talk) 15:14, 27 July 2011 (UTC)

I'm also doubtful that many medical professionals would agree 'the risk is too small to be worth worrying about' when it comes to HIV transmission from oral sex. The risk is probably significantly lower then vaginal or anal intercourse but the general advice is use protection (there are of course a number of other STIs which are more commonly transmitted like herpes).

In fact our article I linked above suggests an '"best-guess estimate"' risk of 1 for 'Fellating a man' compared to a 'Pooled transmission probability estimate' risk of 10 for 'Receptive penile-vaginal intercourse'. This is complicated as [3] [4] [5] [6] attest. Complicating factors in determing the risk include the fact the risk appears to be low, many people who engage in oral sex also engage in other sex acts which are riskier, and people may lie or forget about what acts they've performed for a variety of reasons; so the risk may very well be lower (or higher) then that. But I don't think it's surprising based on the evidence (and basic understanding of HIV) that does exist, medical professionals don't say 'the risk is too small to be worth worrying about'.

Of course, the fact that your partner may know about it is somewhat moot if they don't tell you (which may be illegal in many countries but it doesn't mean it won't happen). And the claim your wife is more likely to die in childbirth then you are to catch HIV from oral sex is completely silly without qualifications like 'on average'. If you're an unmarried woman street prostitute who performs unprotected fellatio and nothing else on many different men many times every day, your wife obviously isn't more likely to die during childbirth then you are to get HIV from oral sex. More to the point, it wouldn't surprise me even if you engage in unprotected insertive anal intercourse several times a year with different heterosexual partners who aren't prostitutes or IV drug users, but have similar behaviour to you, you're on average still far more likely to die in a car accident then get HIV. It doesn't mean it's a good idea or you shouldn't be concerned about your risk of getting HIV. BTW [7] suggests more then 20% of people in the US with HIV (which means 200,000 people) don't know it.

Nil Einne (talk) 17:48, 27 July 2011 (UTC)

Note that the "best-guess estimate" "risk of 1" / "risk of 10" that Nil Einne is quoting from HIV#Transmission is "Estimated infections per 10,000 exposures to an infected source", not a Scale of one to ten. -- 203.82.81.81 (talk) 00:03, 28 July 2011 (UTC)

Whoop whoop pull up, you're off by a couple orders of magnitude. HIV prevalence worldwide is more like 0.8%[8], not 0.001%. And HIV isn't just in Africa, either. From your user page, you appear to be in the U.S., where HIV prevalence among adults aged 15-49 is about 0.6% (ibid). Red Act (talk) 15:58, 27 July 2011 (UTC)

The main reason red meat is bad for you is the mammalian hemoglobins. Imagine Reason (talk) 16:41, 27 July 2011 (UTC)

Is there a source on that? I'm willing to believe it but still curious. I mean, it's not like anyone injects rare steaks directly into their bloodstreams. Several Times (talk) 19:02, 27 July 2011 (UTC)

Nah, Imagine Reason is fairly certainly mistaken. As per Red meat#Health risks, there’s been a little bit of looking into a hypothesis that it's red meat's hemoglobin and myoglobin that's responsible for the correlation between red meat consumption and colorectal cancer. But there certainly isn't a consensus at this point that that hypothesis is correct. And it's generally thought that it's red meat's saturated fat, trans fat, and cholesterol content that's responsible for red meat increasing the risk of cardiovascular diseases and diabetes. Red Act (talk) 04:35, 28 July 2011 (UTC)

• Ignoring the pathogen problem for a second, it would be perfectly safe to consume cooked human blood just as it is to consume any cooked blood. There are lots of foods which are basically cooked blood as a main ingredient, Black pudding, blood soup, etc. As a foodstuff, blood is perfectly OK so long as you treat it like any other animal product (proper handling and cooking). --Jayron32 00:10, 28 July 2011 (UTC)

pathogenic problems aside, blood in sufficient quantities will act as an emetic. Beyond that, it has nothing to do with type and Rh factor: For instance, a human can eat cow meat or even cow blood (many societies do it), but having it xeno-transfused into you would probably result in a massive allergic reaction that might well kill you. HominidMachinae (talk) 07:18, 30 July 2011 (UTC)

July 27

Motor type and most likely wiring scheme

I was given the motor to the right.

Motor

It was taken from an old window AC unit in the US. I think it's a 3-Phase motor but all the 3-phase_AC color codes both inside the US and outside that I've seen have other than what this motor has: black, brown, red, blue, and gray. Peter Michner (talk) 01:26, 27 July 2011 (UTC)

There is nothing recognisable in the photograph to help gauge the size of the motor. (Also the photograph appears to be upside down, or is it attached to the ceiling?) I doubt a smallish motor for a window air conditioner would be 3-phase. Perhaps it is a single-phase motor and the extra cables are to facilitate some operating variation such as two-speed or forward-reverse. Dolphin (t) 03:37, 27 July

2011 (UTC)

Sorry about that. It's about 10cm in diameter, (and sitting on the counter in that photo) so about the size of a regular person's fist. The two other pieces of information it gives are a GE sticker on one side and another sticker that says "HAM-3500(W) 120V 60Hz." Peter Michner (talk) 15:03, 27 July 2011 (UTC)

If you Google Images "air conditioning stepper motor" you get pictures of similar motors with the same number of wires (5). Therefore I think it's a stepper motor, probably used to control the vent direction. This means you need to connect it to a stepper motor driver, not direct to the mains. --Heron (talk) 08:30, 27 July 2011 (UTC)

Interesting. I'd like to see the exact pictures you were looking at, because all the stepper motor wiring diagrams I could find had even numbers of wires, like four or six. Peter Michner (talk) 15:03, 27 July 2011 (UTC)

Here is picture #1 in my search results. It has 5 wires. However, from the other information given in this thread after I replied, it seems that the motor in question is not a stepper. --Heron (talk) 17:12, 27 July 2011 (UTC)

If its a stepper motor, you may be able to feel 'cogging' as you rotate the shaft by hand.--GearCutter (talk) 12:55, 27 July 2011 (UTC)

Actually, it's perfectly smooth. Peter Michner (talk) 15:03, 27 July 2011 (UTC)

Identify butterfly or moth species

The species in question.

View #2.

What species of butterfly or moth (I assume it's one of the two) is this? The photos were taken in Hot Springs National Park near Hot Springs, Arkansas in the United States. Thanks in advance, Ks0stm ^(T•C•G) 02:26, 27 July 2011 (UTC)

It's definitely a butterfly. Butterflies hold their wings vertically at rest, moths fold theirs flat. I think it's a type of swallowtail butterfly. SemanticMantis (talk) 03:54, 27 July 2011 (UTC)

Your image agrees closely with this one [9], which says it is a spicebush swallowtail. Our article spicebush swallowtail has a similar but different picture. The differences could be due sexual dimorphism, or perhaps more than one species goes by that common name. SemanticMantis (talk) 04:03, 27 July 2011 (UTC)

I'm doubtful of this assignment - a spicebush swallowtail is a swallowtail, after all, but I can't see the slightest trace of the tail on the wing after which it is named. And mimicry is common among butterflies... Wnt (talk) 06:17, 27 July 2011 (UTC)

To begin with, I see only two legs in the side view photo, so I'm thinking Nymphalidae, not Papilionidae. Wnt (talk) 06:24, 27 July 2011 (UTC)

This looks like Limenitis, maybe Limenitis arthemis astyanax, which is native to that region. Wnt (talk) 06:32, 27 July 2011 (UTC)

Yep, I think you've got it with astyanax. (`Four-footed' does rule out Papilionidae, but many swallowtails have no visible swallowtail, no?). SemanticMantis (talk) 13:35, 27 July 2011 (UTC)

Sorry for the confusion - you're right, it's just that the spicebush swallowtail does have one. Wnt (talk) 18:05, 27 July 2011 (UTC)

As seen in Knowing (film), could a solar-megaflare kill literally everyone on Earth?

When I saw the spoilers of the end-scenes on YouTube, my first thoughts were:

1. What about anyone in bunkers deep underground? Could they survive there?
2. How about in submarines deep under the oceans? How far down could the solar flares hit there?

I would have confidence that being deep enough underground or underwater would ensure survival. What do you make of this? --70.179.165.67 (talk) 05:55, 27 July 2011 (UTC)

There's no definition of how big a flare has to be before you call it a 'megaflare'. It could just mean 'bigger than the last biggest one'. Presumably if the sun decided to throw half of its mass in our direction then we would be fried. However, in the real world, even the most pessimistic scientists say that a huge solar flare would do nothing more than blow up our power grids.[10] That would be bad enough--millions in the developed world would die--but we would eventually repair all the damage and carry on. I've never heard a serious prediction of a solar flare that could set directly fire to things on the Earth's surface, or even give you sunburn. --Heron (talk) 08:24, 27 July 2011 (UTC)

I just (literally minutes ago) finished reading Sunstorm (novel), which is all about the possibility solar burst wiping out the planet, going kilometres deep and boiling off the ocean. (I recommend it by the way)--Jac16888 ^Talk 12:20, 27 July 2011 (UTC)

"Millions in the developed world would die." Wrong. People dependent on life support in hospitals would die, yes, as would (possibly) some people who were using technology to survive a massive heat wave or a terrible storm, but as the flare would not knock out the combustibility of objects, people would be able to create fires and stuff to survive the winter, and sprinkle water on themselves to survive the summer heat, at least until they got the power grids back on-line. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 23:22, 27 July 2011 (UTC)

I think that A sudden destruction of our electrical and telecommunications infrastructure would be a lot more devastating than you believe it would. For example, the sudden shortage of refrigeration would cause food shortages. Fuel shortages would be a serious problem. Partially because people would be burning gas in generators, partially because almost every step of the process of getting oil from the ground into our cars relies on electric pumps. The economy would suffer greatly, that alone could cause huge number of deaths.

After a week or so, safe fresh water would be difficult to come by in many areas. Even in areas with plenty of water electricity is often required to pump it into water towers.

Virtually our entire economy is dependent on "Just in time" deliveries and manufacturing. Without telecommunications and unlimited gasoline that wouldn't work properly, so even if there was enough food, it wouldn't be in the stores that need it. If those trucks stop rolling and those ships stop sailing people will starve.

Even easy things like staying warm in the winter. You talk about building fires, but where are you going to get enough wood to warm up all ten million inhabitants of New York City alone? And then how are you going to get it to where it needs to be? I'm not sure we could harvest and move that much wood now, let alone in the middle of a global crisis.

After the power was turned back on there would be long term effects. If this happened during the growing or harvesting season, vast amount of crops might be lost. Which could lead to serious starvation. (Remember, we won't be able to just buy food from other countries if they all had the same problem!)

And this all assumes that electronics aren't also damaged in the flare. If microchips are knocked out as well, the vast majority of cars and trucks won't start even if they do have gas! That will make it even harder to transport supplies. (Including gasoline, and the parts we'd need to fix things! Which just compounds the problems!)

It wouldn't be the end of the world, it could all be fixed in time. But it would be far worse than you're imagining, because you're only thinking of consumer uses of electricity. You don't realize that everything else you need to stay alive also depends on electricity. We simply can't go back to an agrarian non-technological life-style with this many people, we need our technology.

APL (talk) 00:09, 28 July 2011 (UTC)

You grossly underestimate the importance of electricity and the cascading failures such as meltdowns and dam failures that would occur, not to mention huge crop losses, deterioration of frozen foods and medicines, and fires in cities, if there were a loss of generators and transformers. Just as a complete continent wide EMP failure would likely kill millions. A world-wide event would kill hundreds of millions easily.

See the FEMA report. μηδείς (talk) 00:21, 28 July 2011 (UTC)

Not related to the original question, but does Knowing remind anyone else of Heinlen's The Year of the Jackpot? --Trovatore (talk) 00:24, 28 July 2011 (UTC)

A "mega-flare" of this type could only conceivably occur when the Sun begins to shed its outer layers.

DNA question

What is the difference between:

1. my DNA and my brother's DNA
2. my (ans my brother's) DNA and a chimp's DNA

I just don't know what kind of differences they are. What is in common in the DNA of all members of a species, and what is different in every member? when they say that 99 percent of human and chimp DNA is the same,what are they exactly talking about?Do I have to study genetics in university in order to fully understand it?--Irrational number (talk) 07:31, 27 July 2011 (UTC)

This definitely won't be the full answer you're looking for, but consider the vast number of boring mundane operations that need regulating in the body and the make up of tissue and cells. Most of the differences between humans and chimps are superficial, and between humans and cabbages for that matter. Hope this helps. Pascal (talk) 07:58, 27 July 2011 (UTC)

If you're looking for raw numbers, humans and chimpanzees share 96% of their DNA, while the average humans differ by only 0.1% (meaning they share 99.9% of their DNA). You can find more information at Human genetic variation. -RunningOnBrains^(talk) 09:57, 27 July 2011 (UTC)

That 0.1% turns out to be 4 megabytes worth of individual human genetic variation, per Human genome#Information content. 99.17.204.52 (talk) 10:20, 28 July 2011 (UTC)

DNA is basically just a (really, really, really) long code of molecules. These codes govern basically everything about your body: making sure your legs grow in the right way, making sure you can digest food properly, etc. A lot of the basic structure in life is similar, throughout ALL life, so a good percentage of these codes are the same in many different species of animals (and even plants!). The more similar the lifeforms, the higher percentage DNA will be the same, which is why chimps, which are primates like us, have 96% similar DNA. But even in other mammals, like squirrels or yaks or beavers, you will find a good chunk of their DNA is similar to ours (don't have the exact numbers, but yeah). Lizards would have a smaller (but still high) percentage, fish probably lower. But yeah, two humans are pretty much the same, DNA-wise. It's tiny, tiny differences in the DNA code that make every person unique (except for identical twins, which have 100% similiar DNA).--66.207.206.210 (talk) 14:21, 27 July 2011 (UTC)

For more perspective, we share 70% of our DNA with sea sponges. -RunningOnBrains^(talk) 14:58, 27 July 2011 (UTC)

Is it known what percentage of human DNA would also be found in an amoeba? Or in E coli? Has someone drawn up an extended family tree? Wanderer57 (talk) 15:27, 27 July 2011 (UTC)

That question raises a difficulty that is important to understand. Most of the exons (the parts of the DNA that encode protein structures) in human DNA correspond to exons in the DNA of amoeba and bacteria, and it is possible to compare them -- that's how the numbers that you see are derived. However, less than 1% of the total DNA belongs to exons. For the remaining DNA (99% of the total), there is no well-established method of doing cross-species comparisons. For a long time most biologists thought that the "non-coding" DNA is mainly junk, but over the last decade it has become clear that there is a lot of important stuff there. Looie496 (talk) 16:07, 27 July 2011 (UTC)

Here is the basic thing you have to understand. A DNA molecule is a string of "nucleotides". There are four possible nucleotides, usually labeled A, G, C, and T. So a DNA molecule can be thought of as a string like "AGGACTTACCTAGGACATTTG...". The string for each DNA molecule is around a hundred million letters long, though. If you compare the DNA molecules in your cells with those in your brother's cells, they can be matched up letter for letter, but there will be a few differences -- something less than 1% of the letters for your DNA will differ for your brother. For somebody less related to you, the number of differences will be larger, and for a different species, larger yet. Looie496 (talk) 15:59, 27 July 2011 (UTC)

Thanks very much. So of the 1% or so of human DNA that encodes protein structures, is it known how much would also be in an amoeba, a bacterium, a nematode, an aphid, a tobacco mosaic virus,...? Is there a lookup table? Wanderer57 (talk) 16:59, 27 July 2011 (UTC)

So is there a accurate boundary between species with regard to DNA difference(or at all)? for example, is it right to say "if the difference is more than X%, then the living things are not of the same species"?--Irrational number (talk) 18:58, 27 July 2011 (UTC)

No, there are no official boundaries. In large part, this reflects the fact that much taxonomic nomenclature predates the discovery of DNA. For modern practice though, there are some rules of thumb. With bacteria (where reproductive definitions of species are moot), typically one requires a new strain differ by at least 1% from existing species before a new species name is assigned. Further, one generally expects at least a 4% difference from all existing genera type specimens before proposing a new genera name. Dragons flight (talk) 20:14, 27 July 2011 (UTC)

Provided you have the same mother, you probably share the same mtDNA.Smallman12q (talk) 02:52, 28 July 2011 (UTC)

I was going to look this up but never got around to it, and won't for a while now - but in general, viruses are extremely efficient in using DNA to code proteins - actually going over 100% sometimes, because more than one gene is coded in the same space due to frameshifts. Bacteria spend a short stretch here and there on regulation rather than protein coding, but do so on a tight budget. The others get increasingly inefficient as their replication rate decreases, and I'd really have to look them up, because it can vary WIDELY among closely related organisms. For example there is a fish Fugu rubripes which has a very compact genome, even though other fishes have all kinds of spam shoehorned in between the genes. And of course humans spend DNA without a thought, it's like some kind of Usenet feed full of Make.Money.Fast and Nigerian bank scams. Wnt (talk) 15:09, 28 July 2011 (UTC)

Starting up a nuclear reactor

Where does the neutron used to start a nuclear reactor come from? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 15:07, 27 July 2011 (UTC)

Spontaneous fissions. Nuclear bombs, on the other hand, don't work properly with such a slow-cooking method of starting up (they "energetically dismantle" themselves before they've really gotten going); so they use a neutron source like a modulated neutron initiator. -- Finlay McWalter ☻ Talk 15:12, 27 July 2011 (UTC)

The joy of a critical mass is that you don't really need to start it with anything special — once you have the material into a critical configuration, any stray neutrons will start the process. There are lots of neutrons out and about in the world, just zipping along, and as Findlay points out, your fissile material (much less impurities hanging out in the fissile material, like Pu-240) already have background neutron rates due to spontaneous fission. With a reactor you have time to just wait for the thing to start up and grow slowly; as Findlay points out, you can't do that with a bomb, because you need all of those reactions to take place in less than a millisecond. --Mr.98 (talk) 15:25, 27 July 2011 (UTC)

To show how easy it is to start a nuclear reactor up, look at Chicago Pile 1, the first nuclear reactor, and see how primitive it was. Most of the complexity in modern nuclear reactors isn't in getting them started, it is in slowing them down and stopping them. --Jayron32 16:22, 27 July 2011 (UTC)

Speaking of which, the RBMK style of reactor uses natural uranium, light water, and graphite. I wonder whether - in theory - it would have been possible (survival optional) for people in Neolithic times to create a nuclear reactor using only a natural uranium ore mixed in with soot at the right concentration... Wnt (talk) 18:02, 27 July 2011 (UTC)

In theory, probably yes, after all, it has happened naturally without any human intervention at all. In practice, of course, Neolithic peoples would have lacked the very detailed knowledge necessary. Still - intriguing plot idea. {The poster formerly known as 87.81.230.195} 90.197.66.97 (talk) 19:19, 27 July 2011 (UTC)

That happened about 2 billion years ago when the natural enrichment of uranium was about 4% of U-235. Nowadays that enrichment is only about 0.7% U-235 which wouldn't be enough for a natural reactor to occur. That's why the difficult step of enriching the natural uranium must be taken before it can be used as fuel for a nuclear reactor. Dauto (talk) 20:27, 27 July 2011 (UTC)

If that were true it would be impossible to operate a RBMK reactor with light water and natural uranium. However, it is possible, so it's possible, in theory, that Neolithic peoples could have created an (albeit very simple) nuclear reactor. However, as it would have gotten hot enough to boil away the water used to cool it, it would probably go supercritical, melt, or both, meaning that it would probably be useless for anything other than starting fires. OTOH, though, it would have been darn near impossible to shut it down, so it could have been very useful as an area denial weapon or to destroy the land of an opposing tribe or, if dropped into water, as a sort of artificial hot spring which could have been used for military (to gather buckets of scalding hot water to use as weapons, and to wash weapons more efficiently,) civilian (to wash clothing and stuff more efficiently,) punishment (to scald people to death as a form of capital punishment,) or culinary (to boil fish,) purposes. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 23:33, 27 July 2011 (UTC)

That's true. But that would be a very tall order for neolithic people. My point was that the naturally occurring reactors happened during a time when it would have been much easier to produce a sustained nuclear reaction even without graphite as a moderator. Dauto (talk) 00:01, 28 July 2011 (UTC)

To be clear, I really don't know if any uranium ore is free enough from the wrong kinds of impurities to be able to start a chain reaction, nor whether enough would occur in one place that it is plausible for someone at a low tech level to collect enough of it. But it seems an amusing scenario for fiction. Wnt (talk) 15:01, 28 July 2011 (UTC)

No, a Neolithic tribe couldn't have made a nuclear reactor. Light water is trivial to come by, and smelting uranium might be possible, but there's no way to get the hyper-pure graphite needed -- a minor, unrecognized contamination of their graphite is one of the reasons the German atom bomb project failed. --Carnildo (talk) 01:46, 29 July 2011 (UTC)

Hmmm, nuclear graphite didn't explain this much, though I'd wondered... still, I'm surprised there's enough boron to foul up the reaction (I assume) everywhere soot can be manufactured. Wnt (talk) 04:05, 29 July 2011 (UTC)

See Nuclear reactor physics#Starter sources and Startup neutron source. Note that besides providing a reliable source for startup neutrons, they also provide an operational check of the low level power meters before startup. -- 203.82.81.81 (talk) 23:49, 27 July 2011 (UTC)

See also neutronium. ~AH1 ^(discuss!) 23:35, 28 July 2011 (UTC)

Um, why? It looks pretty irrelevant to me. --Mr.98 (talk) 02:03, 29 July 2011 (UTC)

Only one higgs?

On the page List of unsolved problems in physics, the section on the Higgs mechanism says: "Does the Higgs particle exist? What are the implications if it does not? Is there only one of them?"
Only one? What? The Higgs boson article says nothing about there possibly being only one. Can someone go into this a bit for me, why we think there might be only one, and what the implications are if that is the case. Thanks. --66.207.206.210 (talk) 15:44, 27 July 2011 (UTC)

Just to be sure we're on the same page, I read the statement as saying that there is only one type of Higgs particle. Do you read it as saying there is only one particle? Looie496 (talk) 15:49, 27 July 2011 (UTC)

(ec) The standard model has only one higgs particle. That's the simplest possible assumption, but nature could be more complex than that and there could be in principle many different higgs particles. Supersymmetric models usually require at least four different higgses one of which is a charged particle. Dauto (talk) 15:51, 27 July 2011 (UTC)

This report quotes Fermilab theorists speculating that there might be up to five kinds of "Higgs" bosons. -- Finlay McWalter ☻ Talk 15:55, 27 July 2011 (UTC)

That's what I was talking about except that they are counting particles differently than what I did. There is a pair of charged Higgses which are anti-particles of each other. If you count those separately, you have a total of five. If, on the other hand, you chose, as i did, to count them only once, then you get a total of four. Dauto (talk) 19:36, 27 July 2011 (UTC)

Well there was this idea once that there was only one electron and it bouncing back and forth in time made all the electrons and positrons in the world and that's why they all had the same charge. Perhaps that has made a comeback? ;-) Dmcq (talk) 17:42, 28 July 2011 (UTC)

One-electron universe -- Finlay McWalter ☻ Talk 17:49, 28 July 2011 (UTC)

July 28

Please identify this Dragonfly species

Please help identify this dragonfly species. The picture was taken in New Jersey on a concrete surface. The animal was just under three inches in length. μηδείς (talk) 04:49, 28 July 2011 (UTC)

My guess is this is a Common Whitetail, check the "adult female" in that article. --Jayron32 04:56, 28 July 2011 (UTC)

There are also several close matches at the genus Libellula, for example check the adult female example at Twelve-spotted Skimmer. --Jayron32 04:59, 28 July 2011 (UTC)

Funny, I told my informant she would get a quick response. Certainly looks like Libulella. I'll post her opinion after I call her tomorrow. Thanks. μηδείς (talk) 05:04, 28 July 2011 (UTC)

Thanks. She is satisfied it could be the female of either species. μηδείς (talk) 19:09, 28 July 2011 (UTC)

Resolved

Any research or speculation in medical literature on using radiation or chemotherapy to treat obesity?

Hi, I was wondering if cancer treatments like chemotherapy and radiation could be modified to treat obesity,(as well as infection). Has anyone seen anything written on this, pro or con, in the medical lit? -Thanks, Rich Peterson24.7.28.186 (talk) 06:02, 28 July 2011 (UTC)

I'm confused, are you sure you mean obesity? Obesity is not caused by any "agent" that could be targeted by chemo or radio therapy. How do you imagine those treatments could be modified to treat obesity? Vespine (talk) 06:12, 28 July 2011 (UTC)

It would be straightforward to treat obesity using chemotherapy or radiation: both of them tend to cause severe nausea, which predisposes against eating. The problem, of course, is that most people see the "cure" as worse than the disease. Looie496 (talk) 06:34, 28 July 2011 (UTC)

If the goal is simply to discourage appetite through prolonged, severe nausea, there are many other things one could consume that don't carry the risk of severe side effects (everything from permanent organ damage through to secondary cancers) associated with antineoplastic drugs or ionizing radiation. TenOfAllTrades(talk) 13:19, 28 July 2011 (UTC)

Sounds more like melting the fat away. You'd make billions. μηδείς (talk) 18:56, 28 July 2011 (UTC)

Horse manure

I saw this on the CBC web site:

But why is horse manure different? Why don't police have to stoop and scoop like everyone else? Sgt. Kristopher McCarthy, of the mounted unit, says that unlike dogs horse droppings have no harmful bacteria. "The difference between dogs and horses is that dogs eat meat and horses do not eat meat," McCarthy said.

Is it true that because horses are herbivorous, horse poop has “no harmful bacteria”? Follow-up question: what about humans who are vegan, does their poop have no harmful bacteria? Mathew5000 (talk) 12:19, 28 July 2011 (UTC)

No, harmful bacteria originate from external sources - they are deposited post deffication. The digestive tract is a pretty harsh environment for bacteria to survive, so only a select group of bacteria can do so. That being said, a carnivorous diet should provide a more nutritious bacteria culture. The point is that, the feces only becomes hazardous after defecation with the progression of time.I'd be more worried about deseases and other-nonbacterial organism that can accompany the feces. I am not a biologist, I am confident in my answer, nonetheless I welcome correction. Plasmic Physics (talk) 12:47, 28 July 2011 (UTC)

Seems like a case of basically right answer, but for the wrong reasons. This does ring true "Within two to three days manure will just dry out and blow away, very similar to clippings of grass." Also my wp:or indicates that carnivores do have worse-smelling feces than herbivores. SemanticMantis (talk) 14:02, 28 July 2011 (UTC)

The stomach is a harsh environment for most types of bacteria, but the lower parts of the digestive system are very hospitable. The digestive system of a horse in fact contains huge quantities of bacteria, and the horse depends on them to survive. In common with other ruminants, the only way they can digest cellulose is by allowing bacteria to ferment it in a structure called the cecum. The large intestine is also massively colonized by bacteria, as it is in all mammals. Looie496 (talk) 17:02, 28 July 2011 (UTC)

And even with all of that, horses pass 3/4 of their dinner undigested. --jpgordon^{::==( o )} 18:14, 28 July 2011 (UTC)

I used to have a neighbour who had a rather unpleasant method for dealing with dog feces on his backyard lawn. He would simply irrigate the lawn, feces and all, and then mow the lot. It's unpleasant due to the horrific smell drifting over the fence. Plasmic Physics (talk) 14:40, 28 July 2011 (UTC)

Horse manure can be fairly disgusting also, and the police are not unaware of that. I vaguely recall there was one protest in Chicago that they apparently must have disapproved of (maybe it was against the drug war) - think it was around the 96 DNC - which they insisted to "crowd control" on horseback. And they must have fed those horses every morsel they could cram down, because they (the horses that is) defecated continuously for the entire short route. The crowd thus had to keep on its toes, but I'd say the joke was on the police in the end, who ended up having to keep their horses in a neat little line for what seemed like hours as some speakers went on at great length ... all the while accumulating a reeking outdoor toilet behind them of positively epic proportions. Now I'm not entirely sure this was the reason, but Chicago eventually started requiring horse diapers in many cases. [11] Wnt (talk) 14:57, 28 July 2011 (UTC)

I guess you linked to that website about the diaper bit but it actually says horse urine smell is a bigger problem then the manure:

According to Sam, horse urine "smells like pure ammonia." He literally threw up one day because of the overwhelming odor, and he spent the rest of the summer with Vicks VapoRub under his nose, all because of the urine smell ("Shit actually doesn't smell that bad. I'd rather clean horse manure than people manure.").

Nil Einne (talk) 08:27, 29 July 2011 (UTC)

Baking powder

Baking powder was not around during the colonial days. It was invented during the middle to late 1800's. What did the colonial women use to make cakes rise? If anyone can answer this, I would be grateful. — Preceding unsigned comment added by TerrDA (talk • contribs) 13:30, 28 July 2011 (UTC)

Baking powder#History Plasmic Physics (talk) 13:46, 28 July 2011 (UTC)

Baking powder is a leavening agent; that article lists several alternatives, including mechanical (whisking) leavening. The "history" section of the cake also talks about various pre-baking-powder cakes and cake-like desserts. It's also noteworthy that lots of cultures used, and use, unleavened foods, like pastries, fritters, or dumplings, in the role that you might expect cakes to take in modern western cuisine. -- Finlay McWalter ☻ Talk 13:52, 28 July 2011 (UTC)

Baker's Yeast has been used since at least the ancient Egypt, possibly much longer. Dauto (talk) 16:09, 28 July 2011 (UTC)

Baking soda predates baking powder, but probably the most common way of leavening a cake at that time was to use beaten egg whites -- that's still the method used for making sponge cakes. Looie496 (talk) 16:53, 28 July 2011 (UTC)

Leavening can happen with natural airborne yeasts as this recipe attests. You just need to leave the dough to stand for a few days. See also Sourdough; "Sourdough starter is made with a small amount of old dough saved from a prior batch, and is sometimes called mother dough or chef. This small amount of old-dough starter contains the culture, and its weight is increased by additions of new dough and mixing or kneading followed by rest or leavening periods. A small amount of the resulting dough is then saved to use as old-dough starter for the next batch. As long as this starter culture is fed flour and water weekly, it can stay at room temperature indefinitely." The article also says that cultured yeast followed the discoveries of Louis Pasteur; before that, Barm from brewing was used. Alansplodge (talk) 19:12, 29 July 2011 (UTC)

Lovely mystery mushroom

Does anybody recognize what this mushroom is? It was spotted while hiking Freeman Creek in the southern Sierra Nevada. --jpgordon^{::==( o )} 14:26, 28 July 2011 (UTC)

Given the location in the Sierras, Calvatia sculpta seems a good possibility. But I'm no expert. Deor (talk) 15:09, 28 July 2011 (UTC)

That looks vaguely reminiscent of the puffball Calvatia sculpta, from about the right area, not close enough to convince me. Wnt (talk) 15:15, 28 July 2011 (UTC) -- note I added this without seeing the previous comment. Interesting we both picked the same thing - in any case I don't mean to naysay the previous poster. Wnt (talk) 15:16, 28 July 2011 (UTC)

I'd venture Calvatia sculpta is correct. It was in the right elevation range in the right location. Cutting one in half to see the puffball insides would be a good way to tell, I suppose, though there doesn't seem to be much to confuse it with. (No, I'm not planning on either eating one or destroying one; they're too pretty on the forest floor.) Thanks! --jpgordon^{::==( o )} 15:25, 28 July 2011 (UTC)

"It was spotted while hiking" - now that is impressive. AndrewWTaylor (talk) 16:14, 28 July 2011 (UTC)

This is the Science Refdesk. Relativity applies here. Smile and the world smiles with you - hike and the world hikes against you. Wnt (talk) 18:04, 28 July 2011 (UTC)

If we could get a picture of that mushroom's backpack it might help to identify it. Bus stop (talk) 18:20, 28 July 2011 (UTC)

Dehumidifier in the desert

I was emptying out my dehumidifier when I had this idea: in places where open water is scarce, like in the Sahara region, why don't they use dehumidifier-like things to extract the water from the air? I understand that the air in those places is obvious not very humid, but even with 1% humidity, one cubic metre of air would yield 10 l of water, which is enough for one person to drink, and maybe even cook if used frugally. Solar power could be used to power the dehumidifier where electricity is expensive or unavailable. Has this been tried before? I'd like to read about it if it has. Thanks in avance. — Preceding unsigned comment added by 118.98.102.191 (talk) 18:16, 28 July 2011 (UTC)

I think you're high by several orders of magnitude: the water content would be measured, even at high RH, in terms of grams of water per kilogram of air. Acroterion (talk) 18:21, 28 July 2011 (UTC)

Yes, see our humidity article. Air at '100% humidity' isn't all water (obviously), but instead air with the maximum possible amount of water vapour present at that particular temperature and pressure - any surplus vapour would condense out as mist etc. AndyTheGrump (talk) 18:27, 28 July 2011 (UTC)

The BBC Weather page for Riyadh gives tomorrow's temperature as 44C with RH of 12%. Using this table (linked from the humidity article) shows that the air there will contain ~7g of water per cubic metre - about a teaspoonfull. -- Finlay McWalter ☻ Talk 18:35, 28 July 2011 (UTC)

Air well (condenser), Dune technology μηδείς (talk) 18:55, 28 July 2011 (UTC)

Here's a common method to capture water in the desert: dig a pit about one metre across and deep, then place an open empty water bottle in the centre of the pit. Spread a plastic tarp over the entire pit and fasten it using pins into the sand. Place a small rock in the centre of the tarp over the bottle, and the moisture will rise onto the tarp, condense and fall into the bottle. ~AH1 ^(discuss!) 23:24, 28 July 2011 (UTC)

Horses whinnying at bicyclist

More than once, while passing a horse going in the opposite direction on a country lane in the UK, the horse has whinnied. Has anyone else experienced this? Does this suggest that some horses think of bicycles plus rider as a kind of horse? 92.24.133.177 (talk) 18:44, 28 July 2011 (UTC)

Could also be fear of the sort Temple Grandin describes with startled cows, see Animals in Translation, as well as Monty Roberts. μηδείς (talk) 19:15, 28 July 2011 (UTC)

I've had horses respond to me as a cyclist producing Horse Noises. Nothing too unusual. ~AH1 ^(discuss!) 23:17, 28 July 2011 (UTC)

What do you mean by horse noises? 92.29.113.104 (talk) 10:19, 29 July 2011 (UTC)

Horse noises. μηδείς (talk) 20:20, 29 July 2011 (UTC)

Trans fat in British soft margarine

When I buy a tub of margarine in the UK, what are the chances of it containing more than trace amounts of trans fat? 92.24.133.177 (talk) 19:43, 28 July 2011 (UTC)

Here in Canada, any processed food containing less than 0.5 grams of trans fat per indicated serving amount can be advertised as "zero trans fat". Always check the nutrition facts. ~AH1 ^(discuss!) 23:16, 28 July 2011 (UTC)

Trans fat is never shown in the nutrition label in the UK. The manufacturers and government regulators keep us in the dark. 92.29.113.104 (talk) 10:14, 29 July 2011 (UTC)

Chocolate for treating depression

Does any study indeed treated depressed people with chocolate to test its anti-depressing effect? (kind of 100 gr. black chocolate in the morning). Quest09 (talk) 20:33, 28 July 2011 (UTC)

Yeah. It doesn't work so well. Please see PMID 16546266. 99.39.4.220 (talk) 21:08, 28 July 2011 (UTC)

A placebo might work, though depression is not purely physiological. ~AH1 ^(discuss!) 23:13, 28 July 2011 (UTC)

Should I get a food processor, mixer, or something else?

My dad doesn't want to have his two unstable teeth pulled for a full denture, but he can't chew vegetables as a result. I'm thinking a food processor would make such an important food group more palatable. Do you agree? I don't think a mixer would be as appropriate? Imagine Reason (talk) 23:08, 28 July 2011 (UTC)

Maybe try a juicing machine for some vegetable juice, such as brocoli? ~AH1 ^(discuss!) 23:11, 28 July 2011 (UTC)

I wouldn't wish a juicer on anyone other than convicted war criminals. You feed the thing £10 of nice fruit and veg and it emits a pint or so of a murky fluid that tastes downright suspicious and causes alarming gastrological disturbances, together with a completely impossible volume of fluffy brown loft insulation. Then you have to spend half an hour cleaning weird paste from the little ducts and sluices in the machine, and another half hour removing tiny seeds from its spinny juicing disc. This explains why charity chops are full of shiny new juicers (on the same shelf as the bread-flavoured-goo-makers). -- Finlay McWalter ☻ Talk 23:32, 28 July 2011 (UTC)

I have an immersion blender which came with a food-processor add-on (so you can chop up veg to make things like soup or salsa). I mostly use it to make smoothies, and my mum uses hers to make creamed (that is, fully liquid) vegetable soups. Its best feature is that it's trivial to clean (one runs the immersion part under a running tap), which means you're happy to use it very frequently (a juicer, in contrast, is torment to clean). In my experience toddlers will happily drink veg (things like carrots) if it's hidden in a smoothie; mayhap your tooth-challenged eldster will feel similarly. -- Finlay McWalter ☻ Talk 23:22, 28 July 2011 (UTC)

Juicers give excellent results from carrots and grapes. Urrghl. But were I starving I'd prefer a blender. μηδείς (talk) 04:55, 29 July 2011 (UTC)

How about using a potato masher on the cooked vegetables? 92.29.113.104 (talk) 10:16, 29 July 2011 (UTC)

This is kind of what I'm looking for. I don't believe in juicers, because they leave behind much of the nutrients. Grapes are high in fructose as well. Imagine Reason (talk) 14:49, 29 July 2011 (UTC)

Try this: [12]. ~AH1 ^(discuss!) 20:11, 29 July 2011 (UTC)

Actually, except for the fiber of a vegetable's cell walls, juicers do extract the large portion of the water soluble nutrients. μηδείς (talk) 20:17, 29 July 2011 (UTC)

July 29

Radioactive casting

When radioactive metals are molten down and cast into ingots, how is the critical mass taken into account when melting down the metal? How is the process different from handling non-radioactive metals? What shapes are typical for radioactive ingots? I have an idea, for a shape: hexagonal column with a hole through the middle, the diameter of the the hole being proportional to the fissile cross section. Plasmic Physics (talk) 03:46, 29 July 2011 (UTC)

I think nobody ever dared to produce an ingot larger than the critical mass of the fissible isotope. As a lot of radioactive elements are not undergo fission for most of the radioactive isotopes you do not have this problem.--Stone (talk) 08:23, 29 July 2011 (UTC)

Surely, more than one ingot's worth of metal is melted down at once? Plasmic Physics (talk) 11:08, 29 July 2011 (UTC)

Hollow spheres and columns are often used for storing very high grade fissile material for the very reason you've mentioned — the air gap increases the critical mass considerably. --Mr.98 (talk) 10:26, 29 July 2011 (UTC)

What is the safety margin, by how much percent is the ingot from critical mass? How about radioactive foil, possibly laminated between layers of wax, for the more radioactive metals? Plasmic Physics (talk) 11:08, 29 July 2011 (UTC)

The requirements are quite detailed and baroque. Calculating critical masses requires a lot of careful work based on the geometry, composition, and neutron moderation or reflection issues. I'm not sure there is one "safety margin" figure. The NRC has all sorts of regulations and approved containers and etc. and these have been designed and reviewed by great numbers of engineers.

Wax is probably not a good thing to use in a radioactive context, because it likely would slow neutrons down (acting as a moderator), which actually increases induced radioactivity and fissioning. --Mr.98 (talk) 11:40, 29 July 2011 (UTC)

How about a silicon based wax? If not, what would you use to protect the foil surface from oxidation, while simultaneously acting as a spacer, and must be flexible? Plasmic Physics (talk) 15:07, 29 July 2011 (UTC)

What your looking for are things like the "upper sub-critical limit" etc. This resent document goes into the Canadian regulations in some detail. Nuclear Criticality Safety Regulatory Document RD-327. This is not to say however, that following them to the letter will avoid you severely depressing your local real estate values and getting the neighbours grumpy. --Aspro (talk) 11:46, 29 July 2011 (UTC)

I was hoping for a percentage. For instance, the neutron flux must be no less than 40% from critcality at any point within the ingot. Plasmic Physics (talk) 15:07, 29 July 2011 (UTC)

Having a molten fissile elements with more than a critical mass just sounds like such a bad idea. There are fission reactors that use uranium metal alloys, but the most common fissile fuel is uranium oxide (UO2), which is produced as a powder (from U3O8 and UF6), packed into molds and sintered together in a furnace. The production process never requires molten uranium. For many of the same reasons that one would have to be careful about molten uranium, there are presumably very detailed rules for the handling and concentrations of such powder to avoid a criticality event; however, the powder has the advantage that it can be handled and formed at room temperature. Many of the alternatives of uranium oxide fuel, such as uranium nitride, uranium carbide, and plutonium oxide, are similarly formed via powders rather than as pure metals. Dragons flight (talk) 16:01, 29 July 2011 (UTC)

Post graduate study in the renowned medical colleges in U.S.

After we are done studying the under graduate classes for M.B.B.S. , we have to have the M.D. degree. So are there scholarship oppurtunities for deserving students to have post graduate study in the renowned medical colleges?113.199.183.176 (talk) 04:01, 29 July 2011 (UTC)

Try checking the websites of those specific colleges, or Google American medical scholarships and Nepalese medical scholarships for your country of origin, based on your IP address. ~AH1 ^(discuss!) 20:08, 29 July 2011 (UTC)

Brain in the heart

There have been several articles on the web spreading this rumor? Are there any reliable sources that talk about heart thinking and memorizing?--Almuhammedi (talk) 08:09, 29 July 2011 (UTC)

Sounds like nonsense. Anyway as for RS, the best I could find is [13] which appears to have been published [14]. Although for some reason on the Royal College of Psychiatrists website, glancing thru it and seeing discussions on things like the human 'spirit' and bioelectromagnetic communication between people doesn't exactly give me confidence in it, perhaps partially explaining why it was published in the The Arab Journal of Psychiatry Nil Einne (talk) 08:53, 29 July 2011 (UTC)

It doesn't take much googling to find people claiming that this discovery that our brains are "really" in our hearts is the literal fulfillment of a Qur'an passage. Maybe this is the Islamic equivalent of the "Lost Day" urban legend. APL (talk) 09:09, 29 July 2011 (UTC)

Seems to have root in this research here where it is apparently discovered that the heart has a small nerve cluster that is used to control and regulate the heart. Probably because the researcher seems to have dubbed this a "little brain", all the crazy pseudo-scientists have latched onto it and made up all manner of crazy stories.

However this nerve cluster is obviously not sophisticated enough to do anything the potions and crystals crowd says it does, if only for the fact that it's tiny. Ants have brains almost ten times larger. APL (talk) 09:02, 29 July 2011 (UTC)

The heart does have a system of cardiac ganglia (little clumps of neurons). Here's a diagram showing where all the cardiac ganglia are.[15] There are neurons connected to the heart for several reasons. Some of those neurons are a part of the parasympathetic nervous system, a system of neurons that regulates the body's functions when the body is at rest. Other of the heart's neurons are part of the sympathetic nervous system, which prepares the body for a fight-or-flight response by, for example, speeding up the heart. And still other of the heart's neurons are a part of the sensory system. But saying that the heart "has a brain" just because it has some neurons is really an exaggeration. The heart's neurons just deal with low-level bodily functioning. There really aren't enough neurons involved to call what they do "thinking". It just looks like some new age types have exaggerated, twisted, and adapted something that started off as a bit of scientific reality to meet their own beliefs and viewpoints, similar to how the flaky quantum mysticism grew out of the scientific quantum mechanics. Red Act (talk) 09:58, 29 July 2011 (UTC)

There's a little more to it than that. The heart has a sort of central controller called the sinoatrial node, which serves as pacemaker for the whole system. It is connected to other parts of the heart by very specialized muscle cells called Purkinje fibers, which function almost like nerves. But I wouldn't myself call this a "brain", and I don't see anything mystical about it. Looie496 (talk) 16:29, 29 July 2011 (UTC)

Think of how clever a gnat is, with such a tiny brain. We can't rule out that there is some thought in the heart and other ganglia. There is an operation, vagotomy, which affects the vagus nerve further away from the brain than the heart, which has subjective effects on a person. The enteric nervous system is also dubbed a "second brain". Vagus nerve stimulation is even said to have anti-depressive effects. I don't think it's unreasonable to suppose that all the little (and large) ganglia throughout the body are part, one way or another, of "thinking", in some sense of the term. Of course, none of this changes that the biggest lump of grey matter is in the head. Wnt (talk) 17:08, 29 July 2011 (UTC)

The brain, heart and lungs are codependant. That's about it. ~AH1 ^(discuss!) 20:04, 29 July 2011 (UTC)

"We can't rule out" coupled with a total lack of evidence and a total lack of connection to what we do understand (in this case about the necessity of sense perception for thought) is what is called "faith". This, however, is the Science reference desk. μηδείς (talk) 20:12, 29 July 2011 (UTC)

Absence of evidence is not evidence of absence. And I described evidence - vagus nerve stimulation as an antidepressant. Of course, the theory to explain that may or may not involve any sort of "thought" in the heart, but it provides a starting point for new hypotheses. Science tells us we should keep an open mind and not declare that all thought (defined how?) must be in the brain. Wnt (talk) 20:31, 29 July 2011 (UTC)

Also note that according to James–Lange theory the heart rate itself is an integral part of the process by which we feel fear. Wnt (talk) 20:40, 29 July 2011 (UTC)

Why do horses whinny?

What is the purpose or function of whinnying, and other horse noises? I know nothing about horses. 92.29.113.104 (talk) 10:23, 29 July 2011 (UTC)

See communication. Cheers. --Jayron32 12:29, 29 July 2011 (UTC)

"Our analysis of the acoustic structure of whinnies of 30 adult domestic horses (ten stallions, ten geldings, ten mares) revealed that some of the frequency and temporal parameters carried reliable information about the caller’s sex, body size and identity." from this 2009 article. Sean.hoyland - talk 12:43, 29 July 2011 (UTC)

Is whinnying different from neighing, or are they just two different names for the same thing? Are these the only noises horses make? 92.29.113.104 (talk) 17:30, 29 July 2011 (UTC)

I don't know if equestrians distinguish whinny from a neigh. For instance, I think whickering is considered fairly distinct from either previous term, but wiktionary [16] just defines it with 'neigh'. I do know that many people can distinguish several types of dog bark, e.g. some barks loosely communicate 'hello, let's play', while other indicate 'back off, or I will bite'. --The point is, there are many, many vocalizations that horses make, and they can communicate many different things. I think this is more important to recognize than what names we call these sounds. Probably the best way to learn is to spend more time around horses and equestrians ;) SemanticMantis (talk) 18:45, 29 July 2011 (UTC)

Mpemba effect

Are there any new studies explaining this phenomenon in details?--Almuhammedi (talk) 13:06, 29 July 2011 (UTC)

this list has articles dating from as early as 1969 and as recently as 2009. --Jayron32 13:13, 29 July 2011 (UTC)

In the hope of pulling in other readers, we should explain that this is the disputed? observation that "hot water freezes faster than cold". I should say that what confuses me about it is: if 35 degree C water freezes faster than 5 degree C water, what temperature is it before it freezes? Isn't it 5 degrees C itself sometime? Though the "convection" explanation from the article might explain this... Wnt (talk) 20:25, 29 July 2011 (UTC)

Transmitter question

what is the full form of STT in STT 433 MHz Transmitter? — Preceding unsigned comment added by 42.104.43.155 (talk) 14:30, 29 July 2011 (UTC)

Not sure, is that its brand name? Is it the company that operates the transmitter? Looking at the wikipedia article STT my best guess would be Singapore Technologies Telemedia or possibly Suomen Tietotoimisto. --Jayron32 14:46, 29 July 2011 (UTC)

A Google search says that it means "Sunrom Technologies Transmitter" -- Sunrom also makes a corresponding receiver called the STR-433. Looie496 (talk) 16:23, 29 July 2011 (UTC)

Another possibility: PTT is very common (especially in old-fashioned handsets, or in HAM radio gear). "PTT" means "push to talk" or "press to transmit" - i.e., hold down a trigger-button while speaking to transmit. STT, on the other hand, can stand for "Speak to Transmit" - in other words, instead of a button, you just talk into the handset or microphone, and it automatically transmits. You're always potentially transmitting (though you probably have a squelch circuit that may or may not be tunable). This mode is also known as "speakerphone," "squelch," "vox", "always on," "hot mic," and so forth. Nimur (talk) 18:15, 29 July 2011 (UTC)

How did Dewar make his flask

I saw a PDF available for $35 from the American Chemical Society, but wasn't going to pay that much just to satiate my curiosity. I just want to know how James Dewar constructed his Dewar flasks in the 1890s. I saw on the first page of the ACS paper how the larger outer flask, that had a tube near the neck for evacuating, was cleanly cut using a wire running a higher current and then pouring cold water on it, after which the smaller flask was placed inside and the outer flask melted back together, and I can imagine that glassblowers melted some glass to seal the portion between the two necks at the top, but I'm wondering how he quickly sealed off the tube at the top after having pumped out all the air. The pressure difference between the inside of the vacuum section and the room in which you're working would have made it hard to just use hot tongs and expect the glass to seal the hole nice and cleanly without molten glass getting sucked in and in general just getting a mucky mess (or just blowing a hole in the neck while you're heating it and ruining your vacuum). 20.137.18.50 (talk) 14:48, 29 July 2011 (UTC)

It's pretty easy to heat a glass tube and get it to constrict and seal under vacuum rather than the glass getting sucked back into the tube. See for example this tutorial. DMacks (talk) 15:01, 29 July 2011 (UTC)

The key point is that glass being, well, a glass doesn't have a single sharp melting point where it goes from completely solid to completely liquid. Instead it has a range of temperatures where it gradually softens. If you apply just enough heat, you can get it soft enough to deform and fuse, but not so soft it loses all structural integrity. So if you melt a glass tube under vacuum, the center of the zone you are heating, being the softest, will collapse inwards and it will do so without deviation as both ends of the tube are under vacuum. The areas adjacent to the center of the zone will be less deformable, and will resist getting sucked inward. And since it's not completely liquid, the adjacent areas will support the more deformable center zone. -- 174.24.213.112 (talk) 15:48, 29 July 2011 (UTC)

(ec) The last page of the document you (IP 20.137.18.50) linked contains this paragraph (hope this helps): "If new flasks are used it is unnecessary to clean them with cleaning solution, but they should be washed with stannous chloride, rinsed and silvered. Rinsing and silvering should be done with a small quantity of liquid, by shaking and rotating, rather than filling the entire space between the walls. Two or three coats of silver are desirable. The silver is then washed out of the evacuating tube with cotton soaked with very dilute nitric acid, the entire flask rinsed several times with water, and the evacuating tube necked down at F for sealing off. Evacuation is carried out at about 400° in the electric furnace over a period of thirty-six hours, by means of a mercury vapor pump and liquid-air trap. Evacuation for a shorter period of time fails to outgas the silver completely and the flask deteriorates rather rapidly. Sealing off is done as soon after turning off the heat as possible. Our practice is to anneal two of the Dewar flasks at once (this requires the moving of one while hot from one ring stand to another already in the furnace) and later to evacuate them together." -- Scray (talk) 15:17, 29 July 2011 (UTC)

Thanks, Scray. I didn't see that part. I wouldn't have thought they'd evacuate that way. I thought they would just attach a tube and turn on a vacuum pump (which I assumed they had in the 1890s). I'm going to have to search 'mercury vapor pump' and 'liquid air trap' now so I can at least visualize what they're talking about. 20.137.18.50 (talk) 16:50, 29 July 2011 (UTC)

Palladium

Why is palladium able to store so much hydrogen? --134.10.113.198 (talk) 16:30, 29 July 2011 (UTC)

See Palladium#Hydrogen_storage and Palladium hydride for a general overview. This google search turns up a veritable shitload of good sources which explore the mechanisms behind hydrogen absorption onto Palladium. This article goes into some really good details of the mechanism. You do need to be a little careful in your research, as the hydrogen/palladium system was the basis for the whole cold fusion bullshit back in the day; but also be aware that the system also has its more commonplace uses, like in catalytic hydrogenation, either as finely palladium on carbon, or in Lindlar's catalyst --Jayron32 17:02, 29 July 2011 (UTC)

Nightmares and Nightterrors.

Exactly what is the purpose of nightmares and nightterrors. --86.45.162.217 (talk) 20:14, 29 July 2011 (UTC)

Couldn't he get prosthetic implants?

Look at Nick: http://www.youtube.com/watch?v=1zzTFrmEQh4&feature=autoplay&list=WLE9874D88A2291309&index=42&playnext=2

If I were in his situation, I'd move heaven & earth to get implants of prosthetic arms and legs and never tire of that pursuit until I have them installed.

Would it be possible to have four prostheses installed on him? What's stopping him for having them? --70.179.165.67 (talk) 20:42, 29 July 2011 (UTC)