Wikipedia:Reference desk/Archives/Science/2012 December 13
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December 13
[edit]Gold complex solubility
[edit]I'm trying to find a reference for the solubilities of sodium aurocyanate and potassium aurocyanate in water, but I'm not having much luck. Can anyone give me a hand? 182.5.158.187 (talk) 04:37, 13 December 2012 (UTC)
- aurocyanate or aurocyanide? This paper [1] has the data for both sodium and potassium aurocyanide. I don't find much of anything on aurocyanates. --Jayron32 04:44, 13 December 2012 (UTC)
- Sorry, aurocyanide is what I'm after. My iPhone's autocorrect seems to know only aurocyanate. 182.5.158.187 (talk) 04:49, 13 December 2012 (UTC)
Animal extract for industrial use as an emulsifying agent (cattle semen & neem oil)
[edit]I run a weekly podcast 1 and a listener emailed our show this question for our "ask us anything segment" where we try to find answers to the most upvoted question. This week, we have to find an answer to the following listener-submitted question:
- As you know, in the cattle industry, ranchers purchase "sexed semen" (which will yield only male calves) and it is a highly expensive process. At least 50% of the semen is wasted and I have a business venture where I'd like to market the excess semen from the industrial sex-selection process and use it as an emulsifying agent for organic pesticide/fungicide. My question is if semen could be used as an emulsifier between water & oil? (in this case neem oil).
Now the only thing I know about emulsification is from the food network, where you have to use dijon mustard as an emulsifier so that the oil & vinegar will come together in a salad dressing. A little more background on neem oil is that it is very good at keeping away aphids, fungus problems, and bacterial/viral diseases from agricultural crops such as tomatoes, peppers, cabbages, etc. 71.52.194.57 (talk) 05:45, 13 December 2012 (UTC)
- Without commenting on the usefulness of semen for any purpose, what makes a good emulsifier is usually a molecule which contains both hydrophobic and hydrophilic portions (AKA Amphiphiles). Many emulsifiers are also good surfactants, so you can get some background from all of those articles. Semen#Composition of human semen has some information on what is in human semen; I wouldn't expect other mammalian semen to be drastically different, and I don't see anything there that jumps at me and says "there's a good emulsifier there". --Jayron32 05:58, 13 December 2012 (UTC)
- The obvious use for it is as a protein supplement added to cattle feed. Recycling at it's best. :-) StuRat (talk) 07:42, 13 December 2012 (UTC)
- Bad idea. See also Cannibal cow. Wnt (talk) 20:09, 13 December 2012 (UTC)
- The core problem is whether it would be economical to use that 50% waste of semen as anything; that is if you were to use it as a protein supplement (or emuslifier, or dentifrice, or adhesive, or whatever else random thing you wanted), it wouldn't just have to be able to be used for that purpose, it would have to be economical enough to repurpose it for that use in comparison to the stuff that is already used for that purpose. --Jayron32 07:46, 13 December 2012 (UTC)
- In my undergrad days, we used fish sperm DNA for blocking in procedures like southern blot. It wasn't just oodles of sperm, though - it was specially treated to extract the DNA and make it biomolecular grade. I always wondered where it actually came from. Did it start as a waste product from a fishery? You could presumably use any sperm for the same purpose, but as Jayron said, it may still not be economical, especially ones competitors are also starting off with waste products. Someguy1221 (talk) 07:54, 13 December 2012 (UTC)
- Think you have asked at the wrong place. A friend looking over my shoulder at this posting (who has made a lot of money at employing Lateral thinking) said immediately. Gosh... I'll buy that stuff – I'm sure the Chines will buy for Traditional Chinese medicine. You should have patented it first.--Aspro (talk) 19:35, 13 December 2012 (UTC)
- Hay, he does not seem to be joking!!! 精 液 (seamen) appears to be mentioned in WP article List_of_traditional_Chinese_medicines#Human_parts_and_exreta. Working for a living does now appear to be a daft idea when you can do a 'Steve Jobs' and steal other peoples ideas.--Aspro (talk) 20:01, 13 December 2012 (UTC)
Oxygen deficiency
[edit]How oxygen-deficient must an atmosphere be to no longer support combustion (e.g. to put out a candle flame)? Can a human being survive in such an atmosphere? In other words, will the candle go out first, or will the survivor die from suffocation first? This is for one of my other novels, the one about the avalanche. Thanks in advance! 24.23.196.85 (talk) 06:43, 13 December 2012 (UTC)
- According to [2], loss of consciousness occurs at ~10% oxygen, although pressure makes a difference, and the time of exposure matters as well. You can remain conscious for almost a minute at 4% oxygen. As for flames, we have an article on limiting oxygen concentration. We don't have any data in there for candles, but paper stops burning at 12% oxygen. Again, pressure matters. In both cases, it also matters what else is in the air. If the oxygen is being replaced by carbon dioxide, both ignition and consciousness become less tolerant of low oxygen concentrations. So anyway, I would conclude that they occur at around the same time. With other materials you'll get different effects. Wood and plastic tend to require more oxygen, whereas flammable gasses, especially hydrogen, require less. Someguy1221 (talk) 07:27, 13 December 2012 (UTC)
- In a sealed room or container, with oxygen being reduced due to animal respiration or combustion, the rise in carbon dioxide will generally cause unconsciousness and death before the decrease in oxygen causes unconsciousness and death. 99.140.249.11 (talk) 19:56, 13 December 2012 (UTC)
- And depending on what the other gases are, you might be worried about conditions like hypercapnia, which for this case of carbon dioxide starts to produce serious symptoms around 5% atmospheric concentration at standard pressure. ~AH1 (discuss!) 22:34, 13 December 2012 (UTC)
- Thanks, everyone! So I gather that flame extinguishment, onset of hypoxia and onset of hypercapnia will happen at more-or-less the same time (i.e. within a few minutes of one another), but the survivor(s) will stay alive and conscious for quite a while longer (although they will feel like their head is about to burst open). Guess that Hollywood has got something right for once... 24.23.196.85 (talk) 22:56, 13 December 2012 (UTC)
Best Alternative of Nose Surgery?
[edit]My nose is little bit big and it looks too ugly. I really feel guilty when I get time to join my friend circle. I am really worry about my ugly nose and extremely want to get rid on it. I afraid with surgical procedure because I have never done it before and also one more reason is that I don't have enough money to expend on it.
So, here…what I m looking for is "the best alternative of nose surgery”, please answer only if you have a real story.
Thanks in advance! — Preceding unsigned comment added by FerlinDesouza (talk • contribs) 07:52, 13 December 2012 (UTC)
- Well, cosmetics might help a bit, and you could try wearing things which draw the eye away. If you're female, perhaps bright scarves, necklaces, and baubles in the hair might help. If you're male, perhaps bright ties, unique facial hair, and necklaces will work. StuRat (talk) 07:57, 13 December 2012 (UTC)
- We have an article on Non-surgical rhinoplasty, which can be used to alter the shape of a nose without surgery, but it can't make the nose smaller, and will probably also likely cost some money. Your best bet is actually to just do a google search for making your nose look smaller. You're not a alone in this, and there are countless websites and instructional videos on using purely cosmetic techniques to give the appearance of a smaller nose. Someguy1221 (talk) 07:59, 13 December 2012 (UTC)
[\l
- My advice: Stop worrying about it. Why should you care about what other people think? Dauto (talk) 15:22, 13 December 2012 (UTC)
- And they might not be thinking what you think they're thinking anyway. HiLo48 (talk) 18:06, 13 December 2012 (UTC)
- Also, when you send out photos, you could photoshop them a bit. Be subtle, though, as any obvious manipulation will just draw unwanted attention. For example, if your nose looks big and shiny, take some of the shine off it in the pic. StuRat (talk) 17:58, 13 December 2012 (UTC)
- The Refdesk does not give medical advice. True, I don't know if cosmetic surgery of this type is more medicine or con artistry, but we really aren't in a position to give any kind of advice. See also Michael Jackson... Wnt (talk) 20:07, 13 December 2012 (UTC)
- Watch Roxanne_(film), then ask your self if you really want a little snorter.--Aspro (talk) 20:29, 13 December 2012 (UTC)
I have a small nose. Trust me, having an enormous conk is less irritating than girls pointing out you have bogeys up your nose. Greglocock (talk) 22:16, 13 December 2012 (UTC)
- Noses give people character. Unless your nose is actually deformed, consider the reaction to the nosejob of Jennifer Grey and its effect on her career, as well as worst nosejobs. μηδείς (talk) 22:48, 13 December 2012 (UTC)
- Here here. Jennifer Grey was the girl-next-door. Here earthiness and spunk in Dirty Dancing made you fall in love with her. Once she had the nose job she just disappeared into the xxxx of the beautiful people. Where you were valued and judged, not for your ability and human attributes but simply for your looks. --Aspro \+(talk) 23:11, 13 December 2012 (UTC)
- That's "hear, hear" for future reference, although I am glad you agree. I had two close friends each of whom had to undergo involuntary jaw reseting in their twenties. The change in appearance was so radical I felt personally attacked. I can only barely imagine how they felt. My understanding or appearance-altering nose-jobs is that they work if you are happy to have everyone who knows you (including an audience) stop recognizing you because you think you will be such a hit with strangers in the future. I have no source that goes into that theory in depth. μηδείς (talk) 04:25, 14 December 2012 (UTC)
- Just to play devil's advocate, why isn't the question posed here a request for medical advice? Oh, I just noticed Wnt already raised that point. Bus stop (talk) 04:30, 14 December 2012 (UTC)
- Because they aren't looking for surgical or medical solutions. StuRat (talk) 04:36, 14 December 2012 (UTC)
I just watched the movie My Girl starring Anna Chlumsky whose nose looked like that sharkboy kid's. I figured she might want a nosejob, and guessed right [3]. μηδείς (talk) 17:50, 15 December 2012 (UTC)
Cerebellum Palsy Spastic
[edit]my kid having CP spastic of 10 years of age. In future when he would grown up my question is that can he raise his family I mean he can perform marital requirements and produce children? — Preceding unsigned comment added by 203.130.19.106 (talk) 07:55, 13 December 2012 (UTC)
- We can't give you any prognosis for your particular kid, but perhaps someone here can provide some statistics on the portion of those with that condition who manage to have children. StuRat (talk) 07:59, 13 December 2012 (UTC)
- Since individual CP cases vary so dramatically, we can't give you an answer (not to mention it would be inappropriate to give a prognosis to a random kid we never met when we have no medical training). You'll have to ask your child's doctor. Someguy1221 (talk) 08:03, 13 December 2012 (UTC)
- Cerebral palsy is a condition defined more by its cause than by its symptoms. The symptoms vary from those invisible to an unaware observer, to almost total debilitation. In general, I can't imagine sperm production being impacted. I know many less severely affected people with CP who have kids. The OP could guess by observing his child's capabilities now. And even if the muscular limitations of the body don't allow normal intercourse, artificial insemination of the mother with the father's sperm is an option I've heard discussed. HiLo48 (talk) 08:06, 13 December 2012 (UTC)
Why are Antioxidants believed to be fat burners?
[edit]if fat "dies" with Beta-oxidation, what would Anti-oxidants enhance it?, as ANTI-OXIDATON agents, they allegedly need to do the EXACT OPPOSITE. please help me understand it ! thanks you fine guys ! — Preceding unsigned comment added by 109.64.147.124 (talk) 10:29, 13 December 2012 (UTC)
- Where did you see the claim that antioxidants are fat burners? I've seen this claim myself on nutritional supplement websites, but no real scientific research on it. It should always be kept in mind that most makers of nutritional supplements are absolutely full of crap. But back to the subject, as you can read at our antioxidant article, it has been popularly speculated that antioxidants may improve the recovery from strenuous exercise, rather than the resulting weight loss, but no study has ever convincingly shown such a connection. Someguy1221 (talk) 10:37, 13 December 2012 (UTC)
- "Antioxidant" is just a fancy name for reducing agent. From what I have heard, the way they are supposed to work as anti-aging medication is by reacting with by-products of oxidative phosphorylation in mitochondria. The unwanted by-products are superoxides and similar radicals, and also hydrogen peroxide (which is produced from the radicals by superoxide dismutase enzymes). But such a broad category of chemicals certainly won't always do more good than harm. Icek (talk) 10:47, 13 December 2012 (UTC)
- Just to explain why superoxides are "unwanted": They tend to react with many substances, including DNA. Mitochondrial DNA is close to the site of production of the superoxides and thus less superoxides lead to fewer mitochondrial mutations, and later to fewer dysfunctional mitochondria. Icek (talk) 10:49, 13 December 2012 (UTC)
- "Fat burning" creates oxidation, thus the diet method of increasing your metabolic rate is fundamentally flawed. You should instead consume fewer calories, which reduces oxidation damage. This is the way to both lose weight and extend your lifespan. There was that study where worms on a starvation diet lived twice as long, but I've never seen any study showing that fat burners increase lifespans. BTW, I doubt if any product can selectively increase the burning of fats, but there are drugs which can increase your metabolic rate, like amphetamines/ephedra. StuRat (talk) 17:56, 13 December 2012 (UTC)
Takeoff distance for Gulfstream G550
[edit]While surfing around this week, I came across this article referring to a shorter takeoff distance than the Wiki article states (based on the company's own website). So I added it as a footnote to the Wiki article. But on further reflection, 3500 ft. is not quite 60% of 5910 feet. I'm not a pilot or a scientist, but I do grok that needed takeoff distance may vary with altitude of the runway and local weather conditions. Still - is it really possible that the G550 can take off in less than 60% of the manufacturer's stated distance? Textorus (talk) 11:37, 13 December 2012 (UTC)
- The article you link to states that the G550 can fly from Tokyo to New York (i.e. maximum range). Where it mentions taking off on a 3500 ft runway it also says "with enough fuel to carry 8 people from one coast of the US to the other". Basic principles of physics mean that if an plane weighs less (as it would when not fully fuelled compared to fully fuelled), it requires a smaller difference in air pressure above and below the wing. So if it's only being flown less than half of it's full range, the plane doesn't need to be fully fuelled and can therefore take off at lower speeds. Also, as you say, weather conditions, altitude, the angle of the runway (flat vs sloped) can all affect the speed required to take off. douts (talk) 13:56, 13 December 2012 (UTC)
- To expand upon Douts' excellent answer a bit: the 5910 ft take off distance has the following small print behind it: SL, ISA, and MTOW. They mean taking off at Sea Level, under ISA conditions, and at Maximum Take Off Weight respectively. Since the G550 can carry a crew of 2 to 4 and 14 to 19 passengers, 8 people is significantly less than the maximum capacity of the plane. There's also the half-empty fuel tank aspect Douts mentioned above. Dncsky (talk) 15:45, 13 December 2012 (UTC)
- And at less than half the range, you need not only less fuel because of the shorter flight time - but also you're using less fuel to haul fuel around! So halving the flight duration MORE than halves the amount of fuel you need. SteveBaker (talk) 20:19, 13 December 2012 (UTC)
- And another effect - at the lighter weight, the stalling speed is slower. This means the aircraft doesn't have to accelerate to the same speed before it can take off; so not as much distance is required to reach takeoff speed. Takeoff distance is very strongly affected by aircraft weight. Halving the takeoff weight will reduce the distance required for takeoff to much less than half. Dolphin (t) 22:54, 13 December 2012 (UTC)
- Got it. Thanks, guys.Textorus (talk) 07:28, 14 December 2012 (UTC)
- And another effect - at the lighter weight, the stalling speed is slower. This means the aircraft doesn't have to accelerate to the same speed before it can take off; so not as much distance is required to reach takeoff speed. Takeoff distance is very strongly affected by aircraft weight. Halving the takeoff weight will reduce the distance required for takeoff to much less than half. Dolphin (t) 22:54, 13 December 2012 (UTC)
- And at less than half the range, you need not only less fuel because of the shorter flight time - but also you're using less fuel to haul fuel around! So halving the flight duration MORE than halves the amount of fuel you need. SteveBaker (talk) 20:19, 13 December 2012 (UTC)
Leaving the Solar System, Part 2
[edit]Let's say I want to populate my theoretical spaceship with foliage, livestock for a food source, and a human population of a few thousand. Once the spaceship leaves the Solar System, it will need to generate it's own heat. What are my best options as far as using radioactive decay to generate heat on the order of a thousand years? Hemoroid Agastordoff (talk) 17:35, 13 December 2012 (UTC)
- I'd say with good enough insulation, the normal activities of everyday life should generate enough heat. And waste heat from machinery makes lots of heat, too. StuRat (talk) 17:49, 13 December 2012 (UTC)
- See also Captive Universe. Ruslik_Zero 18:47, 13 December 2012 (UTC)
- Our article on radioisotope thermoelectric generators goes into substantial detail on the considerations for selecting isotopes. The core problem is that ~1000 years doesn't map well to an RTG; high-energy isotopes have much shorter half-lives (on the order of decades) and so won't last. Long-lasting isotopes simply won't generate much heat at any given point without incredibly prohibitive mass requirements. Spoken generally, though, you'll want an isotope that decays via alpha particles as much as possible (both through the initial decay and on through decay products) with a half-life around double the length of the need for power. A far more reasonable solution, though, would be a proper nuclear reactor; you'll have much better energy density that way even with isotopes that are stable over the length of the voyage.
- As for Stu's suggestion above, basic thermodynamics rules out getting sufficient heat for life processes as a byproduct of those life processes. "Heat from machinery" is fine, but ignores the fundamental question of where that energy comes from in the first place. — Lomn 18:47, 13 December 2012 (UTC)
- If it was perfectly insulated, it would never lose the initial heat, and would accumulate heat instead. It won't be perfectly insulated, of course, but the effect of size also can't be dismissed. Even in large buildings here on Earth, air conditioning may be needed in the middle of winter to get rid of the excess heat generated by all the people and machines. Or, compare to a place with good insulation, like a mine or cave. If you cram too many people in those, they get hot, too. So, I'd look at the problem of how to provide power for generations, for lights, computers, etc. Once you have that solved, the problem of heating the place may already be solved for you. StuRat (talk) 03:52, 14 December 2012 (UTC)
- The basic functions of life (plus stuff running in your house) is certainly sufficient to maintain a livable temperature on Earth, and systems that do that rarely see outdoor temperatures below 270K. How well will those insulation systems work if the outside is far far colder than that? I have a hard time seeing it work without some form of active heating. Someguy1221 (talk) 03:59, 14 December 2012 (UTC)
- Yea, single pane windows don't work in space. :-) Many of the ships we've made so far have been mostly metal, but those were either unoccupied or only had humans in them for relatively short periods. If we want to build a multi-generational ship, we should make them out of materials which insulate better, like plain old dirt. Consider a rotating ring, with metal on the outside, then a layer of soil, and plants on top. That should provide excellent insulation on the outside of the ring. For the sides and top, perhaps a meter of carbon nanotubes, to make it fireproof, as well as insulated. StuRat (talk) 04:12, 14 December 2012 (UTC)
- All of you have the heat problem backwards. Near vacuum is an excellent insulator. The difficulty would be keeping the living area cool enough, not keeping it warm enough. -- BenRG (talk) 16:42, 14 December 2012 (UTC)
- A vacuum stops thermal conduction and convection, but not thermal radiation. In a vacuum flask they use a reflective material to reflect radiated heat back into the flask. You could add such a reflective material outside the space ship, to insulate it further. StuRat (talk) 18:41, 14 December 2012 (UTC)
- Once again, the Reference Desk has led me to exactly the type of article I need. Thanks! Hemoroid Agastordoff (talk) 19:36, 13 December 2012 (UTC)
- If we look at the other needs, like radiation shielding, you'd need 20ft of dirt, minimum to make the trip alive (that is, to produce offspring without too many mutations). That's shielding on the outside, against cosmic radiation, not the one against nuclear power sources. If you want nuclear power, I'd put that somewhere outside the shielding, two birds dead with one stone.
- Delta v is still the main problem. Any propulsion with a decent delta v (say, >0.001c, making the one-way alpha Centauri run in nine parsecs, *ahem* I mean millennia) would easily generate enough power to illuminate the habitats and enough waste heat. If it doesn't, add a layer of silicate foam, rock wool, whathaveyou.
- And take a copy of Wikipedia with you. It'll tell the future generations how to maintain the thrusters and power source. And the servers will add to the waste heat, too.
- "basic thermodynamics rules out getting sufficient heat for life processes as a byproduct of those life processes." LOLWUT? Of course, you cannot convert the heat into enough light to grow the plants, but Stu didn't exactly say that. This topic does develop into a different question, manely how to power a generation ship - a low-maintenance, high-energy density power source is to be considered. I'd go with a huge fission reactor/breeder buffered by liquid hydrogen - not only to catch neutrons, but also to receive additional thrust and make deuterium and tritium which can boost the nuclear reaction. The other side of the reactor is not covered in deuterium; escaping neutrons will contribute to thrust. - ¡Ouch! (hurt me / more pain) 08:40, 14 December 2012 (UTC)
- ASCII art: # = thermal/radiation shielding, (H) = hydrogen tank, (D) = deuterium tank,
- [RB] = reactor/breeder, surrounded by a ring of thrusters.
. ############ . ################# { Thruster } .### ###( H )[ RB ] .## ##( H )[ RB ] .## HABITAT #( H )(D)[ RB ] .## AREA #( H )(D)[ RB ] .## ##( H )[ RB ] .### ###( H )[ RB ] . ################# { Thruster } . ############
- Did you intend for that to look like the starship Enterprise? -- BenRG (talk) 16:42, 14 December 2012 (UTC)
- Ouch, I was thinking exactly of using dirt as an insulator; it can be used to grow foliage, and a thick layer is impervious to the wayward interstellar particle. And yes, your diagram does resemble a Galaxy - class starship, but I was thinking of using a much simpler design, a simple rotating cylinder to provide some artificial gravity. Hemoroid Agastordoff (talk) 17:12, 14 December 2012 (UTC)
- Damn. You're so totally right, BenRG and Hem. Now it does look like the Star Trek vessels but that was unintended. It wouldn't if I had put a 3d model here, for the habitat area is a sphere, not a saucer, and there are not only two thrusters. Let's say a ring of six, eight, or twelve.
- Which just might be the way Star Trek came up with its silly shape - they misinterpreted a blueprint because they made guesses what it would be in the 3rd dimension. We should ask them - the resemblance is just too striking.
- For the dirt, I'd use cheap moon dirt for the outer layers and some Earth soil for inside. Inertia would make you fall towards the R/B core, so the sphere is probably not the ideal shape. It should be an egg, wide side in front, if it's a rotating structure. - ¡Ouch! (hurt me / more pain) 06:47, 17 December 2012 (UTC)
- Ouch, I was thinking exactly of using dirt as an insulator; it can be used to grow foliage, and a thick layer is impervious to the wayward interstellar particle. And yes, your diagram does resemble a Galaxy - class starship, but I was thinking of using a much simpler design, a simple rotating cylinder to provide some artificial gravity. Hemoroid Agastordoff (talk) 17:12, 14 December 2012 (UTC)
- Did you intend for that to look like the starship Enterprise? -- BenRG (talk) 16:42, 14 December 2012 (UTC)
Jeffersonian curved brick walls
[edit]Across the street from Greenfield Village and Henry Ford Museum is a wavy curved brick wall fence at the Ford Headquarters. I was told that walls built in this way are stronger than walls built in a straight line and that this wall was based on an idea of Thomas Jefferson's. If this is true, how does one calculate the ratio of curve needed for maximum strength to the length of the wall? In other words how much would the fence curve back and forth across the line of the equivalent straight fence? And would it actually be stronger?
Thank you very much, Frances F Lukas — Preceding unsigned comment added by HugoPennyful (talk • contribs) 18:04, 13 December 2012
- I wouldn't think it would be universally stronger, but might in certain circumstances. For example, if you have strong winds in one direction, bowing it into the wind would help to distribute the wind loading better. On the other hand, the reverse bowing would tend to concentrate the wind loading forces in the center. This effect would be much stronger if we're talking about water, say during floods. StuRat (talk) 18:12, 13 December 2012 (UTC)
- It should be intuitively obvious that the more curviness (in the right compact shape) the better the overall strength. I don't think there's going to be an equation that will say that a sine wave with a two-foot amplitude will be better than, say, a wall made of overlapping hexagonal cells with some intermediate value of curviness being better. The strength will increase as you approach a solid sphere of brick with no space inside--think an igloo with no empty center. A wall is essentially a two-dimensional object as opposed to a three dimensional solid. What's going on when you introduce bending is that you are increasing the strength by increasing the fractal dimension from 2.0 to 2.1 to 2.2 ... to 2.9 to 3.0, a full solid. If what you want is the various options for strength using a set number of bricks to enclose a variable are, the editors at the math desk should be able to give you some equation. But if we're just talking curviness and strength without a limit on number of bricks and area enclosed then strength approaches its maximum as curviness increases, to the point of a compact solid mass. μηδείς (talk) 18:56, 13 December 2012 (UTC)
- Note that Wikipedia and Wikimedia Commons have many resources about The Henry Ford and some about the headquarters of Ford Motor Company. I'm not precisely sure where or what this wall is, but it's possible that we have photos of it, maybe even an article if we search through our holdings. Anything more you can tell us about it might make it easier to find... Wnt (talk) 20:04, 13 December 2012 (UTC)
- I think this is the wall the OP is describing: [4]. 209.131.76.183 (talk) 20:35, 13 December 2012 (UTC)
- The relevant WP article is Crinkle crankle wall, where Jefferson is mentioned, if only to gainsay those who claim the he invented the design. It's not that they're "stronger", exactly; it's that they don't topple over as a one-brick-thick straight wall would. Split-rail "snake" fences work on a somewhat similar principle. Deor (talk) 20:40, 13 December 2012 (UTC)
- It isn't Ford World Headquarters (the Glass House) that is across from the Village. It is various parts of Ford Research and Engineering on three sides of the museum, expressway on the fourth. Ford has three vague major areas in Dearborn, Michigan. The museum/research area in West Dearborn, the headquarters/Ford Estate area between East and West Dearborn and the Rouge factory complex in South Dearborn. The old headquarters building was over near the Rouge plant, not near the museum complex either. Rmhermen (talk) 14:05, 16 December 2012 (UTC)
- I once took a class in history of architecture, which said the walls of the Pantheon, Rome, are of zigzag brick (hidden by marble facing). —Tamfang (talk) 10:20, 26 June 2013 (UTC)
Is Unha a ballistic missile?
[edit]Is it open for discussion whether Unha is a ballistic missile or not? Colloquially, ballistic missiles are weapons, but technically, it seems to have the same mechanism of an intercontinental ballistic missile. Is that covered by the United Nations Security Council Resolution 2050 or any other UN resolution concerning North Korea? OsmanRF34 (talk) 18:35, 13 December 2012 (UTC)
- Yes, it is a ballistic missile. Ruslik_Zero 18:42, 13 December 2012 (UTC)
- But how does relate to the UN resolutions? Where does it say that North Korea cannot launch satellites for supposedly peaceful purposes? OsmanRF34 (talk) 18:43, 13 December 2012 (UTC)
- Have you actually read our article United Nations Security Council Resolution 1718 or the resolution 1718 itself? What about United Nations Security Council Resolution 1874 or the resolution itself? I'm assuming of course that you read resolution 2050 which you yourself linked to our article of (as our article on 2050 isn't that clear on what the resoluton entailed). Nil Einne (talk) 18:54, 13 December 2012 (UTC)
- OK. That's it. I was looking at the resolution 2050, but could tie it to the message that any ballistic missile is forbidden. OsmanRF34 (talk) 19:02, 13 December 2012 (UTC)
- I take it you meant 'couldn't'. Anyway if you look at resolution 2050, it mentions 1718 and 1874 quite a lot of times, seven times each actually. It mentions a few other resolutions at one stage but the aforementioned resolutions seem to be clearly the key resolutions hence even without bothering to understand 2050, 1718 and 1874 would seem to be the best place to check. Now with comprehension, the 2050 mentions a few other things but basically most of what it says is we want the DPRK to comply with resolution 1718 so we're going to continue/extend what we did in 1874, so resolution 1718 is the obvious place to start in any research in finding what DPRK is and isn't supposed to do, with resolution 1874 as secondary reading. Nil Einne (talk) 19:12, 13 December 2012 (UTC)
- OK. That's it. I was looking at the resolution 2050, but could tie it to the message that any ballistic missile is forbidden. OsmanRF34 (talk) 19:02, 13 December 2012 (UTC)
- Have you actually read our article United Nations Security Council Resolution 1718 or the resolution 1718 itself? What about United Nations Security Council Resolution 1874 or the resolution itself? I'm assuming of course that you read resolution 2050 which you yourself linked to our article of (as our article on 2050 isn't that clear on what the resoluton entailed). Nil Einne (talk) 18:54, 13 December 2012 (UTC)
- But how does relate to the UN resolutions? Where does it say that North Korea cannot launch satellites for supposedly peaceful purposes? OsmanRF34 (talk) 18:43, 13 December 2012 (UTC)
- It's just semantics. Take your ICBM, swap your warhead for a satellite, load a different guidance module, and hey presto! You have a launch vehicle. See for instance Dnepr-1 or Shtil', the changes from the original ICBM/SLBMs are minimal. Fgf10 (talk) 18:58, 13 December 2012 (UTC)
- A bit of reality here. The claims and counter claims about this launch are far more about politics than about the technical aspects of the device launched. All parties seem to be simply repeating their oft-stated party line, expecting others to believe what they say while having little chance to verify any of it. It's good for political leaders and their lackies to have an "evil" enemy they can condemn. It distracts attention from problems at home. HiLo48 (talk) 20:36, 13 December 2012 (UTC)
- There are some differences between a rocket that has been designed for purely civilian use and those which have been designed for military use. You can take a military rocket and use it in a civilian way, but the other direction doesn't always work: the launch payloads may not be large enough, the accuracy might not be very good. In the world of real military planning (as opposed to political posturing), accuracy matters a lot — it tells you how much missile you really have, and whether your nuke matters much. The North Korean missile and nuke programs are still pretty basic — their nukes are tiny and their missiles are probably not very accurate, which means as a real-world threat, as long as you aren't in Seoul you're probably not too bad off. But this sort of technical nitpicking is lost in political posturing... though, perhaps it ought to be. --Mr.98 (talk) 15:01, 14 December 2012 (UTC)
Amount of friction depends on direction, about hair
[edit]I take a single strand of my hair and hold on to one end of it with the fingers of my left hand. Pinching this hair between my thumb and index finger of my right hand just below the fingers of my left hand, I proceed to pull my right hand fingers down the length of the hair. I observe the amount of perceived friction. Next, I take the opposite end of the hair and hold it with the fingers of my left hand and repeat the process with the fingers of my right hand, pulling against the hair to observe the friction. I do this with several different strands of my hair and come to the conclusion that there is more friction between my fingers and the hair strand when I pull in one direction as compared to pulling in the opposite direction. I haven't attempted to see if this finding holds for another person's hair. So my first question is, does this observation have any truth to it? If so, my second question is, what is causing this difference? I'd appreciate any help given! Lord Arador (talk) 19:37, 13 December 2012 (UTC)
- Huge deficit here - I don't think Commons has one scanning electron micrograph of hair! And so neither does the hair article. But see e.g. [5] for such an image of the surface of hair shafts either undamaged or as damaged by blow-drying. Note in all cases the scaly flattened keratinized cells that make up the shaft form a series of flattened plates. Wnt (talk) 19:46, 13 December 2012 (UTC)
- Thanks so much, the images a very helpful. I think this answers my question. Lord Arador (talk) 20:03, 13 December 2012 (UTC)
- We do have File:Human hair SEM.svg, but it illustrates the "scaliness" poorly. And how the heck can SEM give an infinitely-scalable image anyway? DMacks (talk) 20:11, 13 December 2012 (UTC)
- What is infinitely scalable is the image, that is, the vectors defined by a certain form of data. Obviously the SEM gives a certain finite resolution (and discrete data points), but the svg allows for viewing at any given size while retaining smooth curves. Probably someone just traced a raster graphic into svg. Of course, we should be careful when viewing at high zoom levels to not infer that the actual data would look that way, if we had some way of obtaining higher resolution data. SemanticMantis (talk) 23:40, 13 December 2012 (UTC)
- We do have File:Human hair SEM.svg, but it illustrates the "scaliness" poorly. And how the heck can SEM give an infinitely-scalable image anyway? DMacks (talk) 20:11, 13 December 2012 (UTC)
Opposite of Liebenberg syndrome?
[edit]Liebenberg syndrome is in the science news of late. (E.g., When An Arm Is Really A Leg.) Does anyone know the opposite, when one's feet develop like hands? Google searches are not helpful and our article is stubby. μηδείς (talk) 21:21, 13 December 2012 (UTC)
- In fiction, Willy Wonka claims to have produced a vitamin that makes your toes grow as long as fingers. It's of course hard to tell how serious he is. – b_jonas 14:09, 17 December 2012 (UTC)
Peer review and research merit
[edit]Hi all, in Australia, the National Statement on Ethical Conduct in Human Research, hereinafter referred to as the "National Statement", says the following: "1.2 Where prior peer review has judged that a project has research merit, the question of its research merit is no longer subject to the judgement of those ethically reviewing the research."
I am basically curious about the standard of "peer review" implied above. I know no one here is authorised to interpret the National Statement, but I am not asking for an authoritative interpretation, just for information on the issue. What I want to know is the Ref Desk's answer based on practices/ experience elsewhere. For a journal article, "peer review" may require getting three experts in the field to determine suitability for publication. But for determining "research merit", one would expect the standard to be considerably lower for who can count as a "peer". Does anyone know of any actual standards used in research anywhere? I'm thinking along the lines of, say, something you might have encountered in research (I believe there are numerous researchers reading this page). It would be especially great if anyone knows of cases where these standards have been made explicit, but that may be too hard to find. Please feel free to give less rigorous examples, where, say, you had to convince some panel of experts before conducting research. Was it a narrow panel with specific expertise, or did they have a general panel for covering a whole discipline? IBE (talk) 22:04, 13 December 2012 (UTC)
- Does the Wikipedia article Peer review help at all? --Jayron32 23:09, 13 December 2012 (UTC)
Er.. my bad - yes I should have thought to do some reading first. I'll read it presently (cursory view suggests very good). Still curious about exact experiences by people here, but the article suggests there are different levels of peer review for different purposes, depending as one might expect on the costs involved, financial and otherwise. IBE (talk) 23:21, 13 December 2012 (UTC)
- That might not help you in this case -- the statement has a special meaning that you have to be "in the loop" in order to decode. What it means in practice is that if a researcher has received a (peer reviewed) grant to perform a certain type of research, the ethical review board is not permitted to reject the proposal on the basis that it has insufficient research merit. They can reject it if they feel that subjects (human or animal) will not be protected adequately, but they can't reject it because they feel it has insufficient value. In many cases, though, review panels are called upon to judge proposals for "pilot projects" that haven't yet been funded -- in that case, part of the duty for the panel is to judge whether the project is important enough to justify the way that it uses subjects. Looie496 (talk) 23:48, 13 December 2012 (UTC)
- Thankyou - what do you mean by "that might not help you"? Are you referring to my last sentence: the fact that there are different levels of peer review? Remember also that being "in the loop" is not more precise than being a "peer", so it must still depend on interpretation, which either depends on authority to interpret (as with judges interpreting the law) or established practice (as with judges using previous case law). My personal concern involves PhD projects, which are (fairly typically, I think) approved by supervisors, heads of school, and the academic board. The funding for scholarships, and the extra funding within a school, has been allocated. Then ethics has its fun. I'm curious as to prevailing standards, because there is nothing in the word "peer" itself which would rule out these three levels as sufficient, but there is plenty in practice that might. IBE (talk) 01:06, 14 December 2012 (UTC)
- Also, I've read the article, and it's a wandering mess, but it's most crucial point is: "Thus, the terminology has poor standardization and specificity, particularly as a database search term." So we have a new standard of exactness for our terminology: usefulness as a search term. — Preceding unsigned comment added by It's Been Emotional (talk • contribs) 01:09, 14 December 2012 (UTC)
- What I meant by that is the article on peer review. What I was trying to say is that the rule in question, in spite of its wording, does not really have anything to do with peer review -- its purpose is to prevent ethics committees from rejecting as bad science projects that have already been awarded grants by external agencies. The wording about peer review is a way of obscuring the fact that the rule is really about money. Looie496 (talk) 01:33, 14 December 2012 (UTC)
- Very interesting point: that the rule is about money. Which at least makes perfect sense. IBE (talk) 01:43, 14 December 2012 (UTC)
- What I meant by that is the article on peer review. What I was trying to say is that the rule in question, in spite of its wording, does not really have anything to do with peer review -- its purpose is to prevent ethics committees from rejecting as bad science projects that have already been awarded grants by external agencies. The wording about peer review is a way of obscuring the fact that the rule is really about money. Looie496 (talk) 01:33, 14 December 2012 (UTC)
It seems to me that the Australian rule forces an all-or-nothing view of things that perhaps should be judged on a spectrum. Suppose a project is going to give a moderate amount of distress to research animals. Maybe if success of the project would mean finding a cure for cancer, it would be appropriate for the ethics committee to say that the project has "enough merit" to warrant the ethical downside, whereas if success would mean a real but minor increase in our knowledge with no prospect of practical application, it might be appropriate for them to say that, despite an outside finding of project merit, there's "not enough merit" to warrant the distress to the animals.
(1) Has the ethics community considered and rejected this non-binary perspective?
(2) And, how about the other main research countries -- do they do it the same binary way as Australia?
(3) The above description of the Australian approach implies to me that you apply for the grant first, and once the grant is offered (merit is established) then you go to the ethics committee. But I would think that universities would make you go before the ethics committee before letting you send out the grant application. Which sequence is more commonly used? Duoduoduo (talk) 15:44, 14 December 2012 (UTC)
- I'm an American, so I can't speak directly for the Australian system, but it probably works pretty similarly to ours. There are two important factors: (1) Grant proposals are typically not written at the level of detail that an ethics committee needs -- i.e., exact numbers of subjects and exactly how each subject will be treated. (2) Members of an ethics committee are typically not well suited to judge the research merit of proposals. They have to be experts on ethical issues, but they usually aren't experts on the science involved in a specific proposal. Commonly a researcher has to go to the ethics committee first to get approval for pilot studies on which a grant proposal is based, and then if the proposal is funded, go to the committee again for approval of specific experiments. During the pilot stage, the ethics committee needs to pass judgement on the research merit of an experiment, but their judgement is often pretty perfunctory, unless the experiment involves unusual amounts of pain or distress. After the grant has been funded, the ethics committee no longer concerns itself with research merit, only with direct ethical issues. The rationale is that the panel at the funding agency are experts on the science in the proposal, and so it wouldn't make sense for the ethics committee to overrule them. That doesn't mean the ethics committee can't block an experiment if they feel something is wrong -- nobody can force them to approve a protocol if they don't want to. Looie496 (talk) 19:53, 14 December 2012 (UTC)
- Thankyou both for these further replies. The Australian system probably varies, but the particular thing I am talking about is as described for PhD students, where the Programme of Study is the "bread and butter" document that gets thrashed about before the research is basically approved. This is the bit I refer to above, which is approved by supervisors, heads of school, and Academic Council (maybe existing under a different name at other universities). The process Looie discusses is different, in that the prior consultation with an ethics committee is exactly what we lack, and exactly where our committees seem to be messing about without a clearly defined role. The American system (university? hospital? everywhere?) seems more professional. I'd be curious to read more on the American system, if Looie can point me to anything, including formal documents like our National Statement. Also personal testimony in published sources (blogs are a tolerable substitute for a starter, but I prefer something that would sound good in debate). Any more info welcome. IBE (talk) 01:05, 15 December 2012 (UTC)
How do I know, what size pipeclay triangle to buy for a particular crucible? Plasmic Physics (talk) 23:33, 13 December 2012 (UTC)
I have the option of three sizes: 75, 65 55 mm. The crucible size is 46 x 53 mm (h x d). Plasmic Physics (talk) 00:54, 14 December 2012 (UTC)
- Is this pipeclay question a geometry problem ? That is, are you asking us what size equilateral triangle can be inscribed in a 46 × 53 mm rectangle ? The diagonal of the rectangle is only a bit over 70 mm, so the full sized triangle is definitely out. I'm not sure if the two smaller triangles would fit. StuRat (talk) 04:03, 14 December 2012 (UTC)
- I don't know if it is a geometric problem, but it is definitely a practical problem. The question is primarily aimed at someone with laboratory experience. There has to be a match there somewhere, they are sold by the same company. Plasmic Physics (talk) 04:59, 14 December 2012 (UTC)
- I'm asking you to clarify your question. Are you asking us which one is the largest which will fit ? StuRat (talk) 20:06, 14 December 2012 (UTC)
- Oh, OK. No, I'm asking which one is the overall most suitable, if that happens to be the largest which will fit, then so be it. Plasmic Physics (talk) 21:21, 14 December 2012 (UTC)
- I'd go with the smallest one. The largest won't fit at all, and if the mid-sized one fits, it's will be quite a tight fit, and you need to allow for thermal expansion. StuRat (talk) 23:06, 14 December 2012 (UTC)
- FYI: the crucible should rest inside the triangle, so that it can be mounted on top of a tripod. Plasmic Physics (talk) 00:08, 15 December 2012 (UTC)
- The crucible is a truncated, elliptic paraboloid, 53 mm is the largest diametre. The triangle consists of a wire frame, with three claypipes covering it in part, forming the edges of a triangle. Plasmic Physics (talk) 00:20, 15 December 2012 (UTC)
- OK, I see. You want to place a crucible: [6] on top of a pipeclay triangle [7]. I'm not quite clear what the dimension you give for the triangles represents. Is that the length of the clay pipes, or the length of the wire ? (I assume the clay.) Is 46 the diameter of the crucible at the bottom ? It still sounds like the smallest triangle is what you want, as the crucible would fall right through the center of the larger ones. An inscribed equilateral triangle with sides of about 42 would fit inside a circle with a diameter of 46. Using the triangle with 55 mm clay pipes should therefore cause them to extend out beyond the crucible a few millimeters on each side, which sounds like the most stable configuration. I drew it up on MS Paint, and it looks about right. StuRat (talk) 03:10, 15 December 2012 (UTC)
- This page seems to suggest that you don't want to place the crucible on top of the triangle, but rather inside it: [8]. However, I don't think even the largest triangle would allow for that. StuRat (talk) 04:24, 15 December 2012 (UTC)
- I'm not sure what the dimension represents, although I guess it is the length of one edge of the triangle. 46 is the height. The crucible is supposed to fit inside, with the bottom hanging beneath the triangle so that it may be heated. Essentially, the triangle needs to be big enough to allow the crucible to sink into the triangle and not rest on top, and small enough not to let it slip through completely. Plasmic Physics (talk) 05:39, 15 December 2012 (UTC)
- OK, good, now we're getting somewhere. However, we seem to be missing a critical dimension, the diameter of the crucible at the bottom. StuRat (talk) 05:43, 15 December 2012 (UTC)
- It measures 25 – 30 mm. Plasmic Physics (talk) 00:56, 16 December 2012 (UTC)
- Ask the company? Their job is to sell stuff, and my lab experience is that many scientific manufacturers are reasonably interested in helping me figure out what they can sell me. Also try looking for kits or full sets of equipment (often targeted to hobbyists or students...they would have "matched"/self-consistent pieces. DMacks (talk) 14:31, 14 December 2012 (UTC)
- I have asked them, still waiting for a reply. It's not like the US over here - it's slim pickings, so no kits; I have to assemble my lab from scratch, I'm not about to start importing. Plasmic Physics (talk) 21:21, 14 December 2012 (UTC)
- Yup:( On the other hand, vendors don't have to know that you aren't actually planning to order from them after they help you out with information:) DMacks (talk) 18:20, 15 December 2012 (UTC)
- I have asked them, still waiting for a reply. It's not like the US over here - it's slim pickings, so no kits; I have to assemble my lab from scratch, I'm not about to start importing. Plasmic Physics (talk) 21:21, 14 December 2012 (UTC)
Nevermind, I've got my answer. Plasmic Physics (talk) 03:38, 17 December 2012 (UTC)
- Which is ? StuRat (talk) 00:20, 18 December 2012 (UTC)