Wikipedia:Reference desk/Archives/Science/2012 May 11

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May 11[edit]

before penicillin[edit]

Penicillin was not widely used before the 1940s but what did they use before then to treat illnesses such as inner ear infections strep throat and pneumonia? — Preceding unsigned comment added by Wrk678 (talkcontribs) 00:42, 11 May 2012 (UTC)[reply]

See Antibacterial#History, antibiotics are not as necessary to treat infectinos as much as we have come to rely upon them. For an ear infection for example, avoiding dairy/sugary products and keeping the ear dry can help while your body fights off the infection itself. Unique Ubiquitous (talk) 01:06, 11 May 2012 (UTC)[reply]
Basically these are infections which would have killed many people who acquired them: if the initial infection didn't see you off, then a secondary infection or complication may have. They still have the potential to kill people without good immune systems, such as elderly, children or people on immunosuppressant drugs. --TammyMoet (talk) 09:16, 11 May 2012 (UTC)[reply]
Well, that Polygonum I mentioned a few days back was also used for ear infections by Dioscorides [1] (see Panicudine, which I started then) - also Stipa of some sort, Psyllium; also an elxine, Parietaria or Helxine of which this translation's author seems uncertain of the identity, but which sounds like some seriously good stuff. I mean, remember, Dioscorides didn't know that purulent ears, inflamed tonsils, erysipelas (cellulitis), chronic cough, and "all types of inflammation" would be treated by antibiotic - yet he ascribes all those activities to this plant, and not to a different larger form of "helxine" for which he has a separate entry. I'm pretty convinced the ancients knew their stuff, even if they did occasionally add in some white lead in hair-raising concotions. We could learn a lot from them. N.B. there is absolutely zero information about antibacterial properties of the plants suggested as elxine in PubMed, despite that remarkable paragraph by Dioscorides. Wnt (talk) 12:06, 11 May 2012 (UTC) Note: Nicholas Culpeper, writing on Pellitory of the Wall, gives a description more like a painkiller. [2] Nonetheless, I'm not at all sure this is what Dioscorides was writing about. Wnt (talk) 14:42, 11 May 2012 (UTC)[reply]
I'm also surprised that the antibacterial properties of Honey aren't separately mentioned in the article quoted by Unique above. They've been well known about for some time, before being rediscovered by medicine in the last few decades. --TammyMoet (talk) 13:51, 11 May 2012 (UTC)[reply]
Inner ear infection is mostly caused by a virus, so no real treatment exists; Pneumonia was a killer disease before antibiotics; can't find a lot on treatments for these, it's as if before the 20th century everyone was busy trying to cure syphillis. Toxic metal compounds were used a lot, arsenic in the form of Fowler's solution, arsphenamine, or arsenic trioxide; thallium salts, various forms of mercury, like mercury(II) chloride. See also medical uses of silver. Ssscienccce (talk) 14:15, 11 May 2012 (UTC)[reply]
Actually, it is not impossible that an herb could be an immune modulator after the fashion of imiquimod; the right modulator might persuade the body to put on a different and possibly more useful immune response toward an infection. Wnt (talk) 14:42, 11 May 2012 (UTC)[reply]
The short answer is that prior to the development of antibiotics, a lot of people who developed serious bacterial infections died because there just weren't any effective alternatives. My grandmother's sister died in her late teens from an infection caused by a troublesome wisdom tooth. Without proper antibiotics, you're left with plain old supportive care: keeping the patient comfortable, supplying IV fluids as needed, and hoping for a good outcome. TenOfAllTrades(talk) 14:28, 11 May 2012 (UTC)[reply]


My doctor always told me that without antibiotics a inner ear infection will cause the eardrum to burst, not to mention the fact that an inner ear infection is extremely painful. Although some ear aches are caused by viruses most ear infections that last more than a day or two are caused by bacteria. — Preceding unsigned comment added by Wrk678 (talkcontribs) 01:41, 12 May 2012 (UTC)[reply]

Not sure if it was used for the three specific infections mentioned by the OP, but Sulfonamide (medicine) was used before penicillin. The Prontosil form of sulfa was introduced in 1935., and was effective against streptococci. Actual sulfa was an old drug (1906) and out of patent. It was very helpful in WW2and the article says it saved tens of thousands of wounded soldiers from death. Before sulfa came into use there was [[Arsphenamine}Salvarsan]], used starting around 1910 to treat syphilis. Before these, physicians used a variety of chemotherapeutic agents with limited success, such as carbolic acid, alcohol, iodine, and iodoform in the peritoneal cavity or elsewhere. These agents might kill pathogens, but tissue damage was also likely. Quinine was effectively used to treat malaria. A typical recommendation from 1904 was to treat infections by "absolute rest of both the patient and the part involved, drainage and evacuation of septic foci, soothing and cleansing applications to the parts, promotion of elimination and support of the patient." This is not so different from what a homeopathic doctor would have done at the time, except the "regular" or allopathic physician might open, irrigate and drain] the infected area. Not sure what the doctor of the pre-antibiotic era would do to treat an inner ear or throat infection, but a mastoid infection would be surgically drained, and antiseptics might be instilled in infected areas such as sinuses or the abdomen or genitals. By [3], war surgeons found it effective to use diluted bleach with other chemicals (Dakin's solution) to treat wound infections. Back in the 19th century, a physician would have likely treated an infection by administering a highly poisonous mercury compound called Calomel, by purging the patient with laxatives, and by bleeding the patient, which were rarely beneficial and all of generally increased mortality and had severe side effects. But even back in the US Civil War, some surgeons treated abdominal infections by irrigating with boiled (and cooled) water, before they had a clear germ theory of disease. Edison (talk) 04:17, 12 May 2012 (UTC)[reply]

For a project with strict rules against giving medical advice, I reckon this thread is dangerously packed with misinformation and quackery. We really shouldn't be describing non-professional "cures" here. HiLo48 (talk) 04:35, 12 May 2012 (UTC)[reply]

Do you have a beef with referenced historical information which answers the OP's question about how infections were treated before penicillin? Any accurate answer to a question about how things were done in an earlier era will describe ways which are no longer considered optimal, whether it is farming, fighting a war or fighting infection. Edison (talk) 04:39, 12 May 2012 (UTC)[reply]
Not at all, but a lot of the "advice" above is not "referenced historical information". HiLo48 (talk) 04:45, 12 May 2012 (UTC)[reply]
If you see misinformation above, or advice, by all means, point it out. Wnt (talk) 21:12, 12 May 2012 (UTC)[reply]
I see some ill-founded intuitive suggestions, based on original research, by guess, and by gosh, as well as my response which is based on a search of books from the pre-penicillin 20th century. Before penicillin there was sulfa, before that there was supportive therapy, giving the body a chance to heal itself and the immune system a chance to defeat the infection, along with operations to drain abcesses, boils, and other foci of infection, and the questionable use of chemical antiseptics which killed pathogens but also harmed body tissues, This is distinct from earlier medical quackery with calomel, bleeding and purging. Edison (talk) 03:40, 13 May 2012 (UTC)[reply]
I didn't see any misinformation there - there was no claim that was a good idea, just what the "doctors" did. It is of course true that many Western practices up even to the 1800s were frightfully backward by comparison with the standard of care one would expect in ancient Rome or medieval Islam. Wnt (talk) 18:11, 14 May 2012 (UTC)[reply]

Minimizing the effects of aging on skin[edit]

How a person can minimize the effects of aging on skin? Is life extension technologies or hormone replacement therapies developed enough to make someone look younger at their old age? What is the possibility of research progress in the next 30 years? Should Resveratrol supplement from a much younger age help someone to prevent aging-related changes in skin? What measures should be taken by someone who is 19 years old to delay aging? --NGC 2736 (talk) 03:58, 11 May 2012 (UTC)[reply]

While there is not a great deal of publicly available good scientific research on the subject of preventing skin ageing, beauty therapists are trained to advise on this. I'll give you some advice here, which any beauty therapist would be able to give you: drink plenty of water, use a good moisturiser day and night, cleanse your skin thoroughly before you go to bed and when you wake up, eat a balanced diet, don't smoke - and choose your grandparents well. Whether you should supplement with anything is medical advice which we can't give here. --TammyMoet (talk) 09:10, 11 May 2012 (UTC)[reply]
And don't, under any circumstances, lie around half-naked in the sun! FiggyBee (talk) 09:28, 11 May 2012 (UTC)[reply]
Calorie restriction, avoid over-cooked food, alcohol, fermented meat & donuts. Eat lots of salad and fruit. SkyMachine (++) 09:52, 11 May 2012 (UTC)[reply]

What is the most accepted theory of aging? --NGC 2736 (talk) 10:17, 11 May 2012 (UTC)[reply]

See senescence for the general theory. As for skin, of those listed above, avoiding UV exposure is, by far, the most important. This can be done be staying inside, covering up when outside, using sunblock, etc. And absolutely never use a tanning bed. StuRat (talk) 15:03, 11 May 2012 (UTC)[reply]
See Photoaging for the specific theory relating UV-light and aging. OsmanRF34 (talk) 21:43, 12 May 2012 (UTC)[reply]
I think it goes well beyond theory at this point, it's an established fact. StuRat (talk) 22:18, 12 May 2012 (UTC)[reply]
It is a theory. But the proper meaning of 'theory' is not 'hypothesis', it is 'an explanation backed by facts.' Anyway,, I don't think there are any doubts in the connexion between UV rays and skin aging. ~~ — Preceding unsigned comment added by OsmanRF34 (talkcontribs) 11:59, 13 May 2012 (UTC)[reply]

Is Element Zero In Mass Effect Possible[edit]

In the Mass Effect series theres an element that effects the mass around it when charged with electricity. Its usually found near pulsars and neutron stars. Would this kinda thing be possible cause you can control gravity with this stuff. — Preceding unsigned comment added by Lightylight (talkcontribs) 04:23, 11 May 2012 (UTC)[reply]

Whether the stuff can control gravity or not doesn't matter. In either case, the stuff isn't possible. Plasmic Physics (talk) 08:21, 11 May 2012 (UTC)[reply]
See antigravity. The ideas are just as speculative but you'll get more respect from the crowd if you describe them in those terms. Wnt (talk) 11:45, 11 May 2012 (UTC)[reply]
Atoms are made of electrons, protons and neutrons. Elements are numbered according to the number of protons (which is the same as the number of electrons) that they have. An "element zero" would presumably have none of either - so it could only consist of neutrons. We actually have an article about this: Neutronium. An "atom" consisting of just one neutron would not generally be described as an "atom" - so we don't normally place it on the periodic table at number zero - but we could - and several people have actually done that. Sadly, a neutron left on it's own decays with a half-life of around 15 minutes - so there wouldn't be much of this stuff around for very long unless something was continuously replenishing it. You can also have groups of more than one neutron (which, technically, would be isotopes of neutronium) - and groups of two neutrons (Dineutron) have definitely been observed in nature. Tetraneutron (a group of four neutrons) is hypothesized to be possible - and there is some evidence that it actually exists, although this is controversial.
However, I doubt we'll find that we can control gravity or do anything else particularly exotic with neutronium. Sometimes science fiction is just fiction. 216.136.51.242 (talk) 15:07, 11 May 2012 (UTC)[reply]
Now that we're talking about actual neutronium, what is its theorised state in a neutron star - liquid or solid, or super-solid? Can it even exist in the liquid phase, or does it sublime under all conditions? Plasmic Physics (talk) 06:29, 12 May 2012 (UTC)[reply]
I should note that "Element Zero" is the nickname, not its place in the periodic table. That said I don't see a potential way any chemical, elemental or compound, could change its mass when subjected to an electric field. Mass is a function of gravity attraction, which, according to the most commonly accepted theory, is a function of the curvature of spacetime caused by an object "resting" on it (in a fashion somewhat similar to a giant rubber sheet). This is a massively gross oversimplification but it explains the problem well. The conservation of matter states that you cannot create matter, which is the only thing that has mass, or destroy it. For an "element zero" to be possible it would have to destroy in a reversible way mass when a current was applied so that its "dent" in the sheet would become greater or lesser. In general it would require the relativity model of gravity to be wrong and Gravitons to exist, and somehow the element to generate a field that interacts with gravitons. The theories that posit Gravitons have serious problems (as the article points out). And beyond that, even if Graviton theories were true it is probably not possible to interact with gravitons in a meaningful way because they would be massless particles that have a very low probability of any sort of interaction with other forces. HominidMachinae (talk) 19:26, 12 May 2012 (UTC)[reply]

is the file autorun.inf executable by itself?[edit]

I have an autorun.inf file in my USB and it looks like some kind of messy code in notepad, but I cannot find any other application linked to this file. I wonder if it is some kind of malware that is executable by itself?--Noname67097 (talk) 05:24, 11 May 2012 (UTC)[reply]

autorun.inf is a file checked for by Windows when you insert a CD or other volume device, and contains instructions about what to do when that volume is inserted into the computer. It is not an executable in itself, but can cause Windows to launch some other executable. FiggyBee (talk) 05:43, 11 May 2012 (UTC)[reply]
Thinking out loud, what if you rename a *.exe file to autorun.inf. Will windows execute the code? Zzubnik (talk) 11:24, 11 May 2012 (UTC)[reply]
Well, the article says it's a text file, so no sane computer should try to run it. Then again, this being Windows, who knows? Wnt (talk) 11:43, 11 May 2012 (UTC)[reply]

For the future, note you're probably better off with questions like this at the Computing Reference Desk. -RunningOnBrains(talk) 19:41, 12 May 2012 (UTC)[reply]

What's the term for one way only traffic lane design?[edit]

Hi,

I remember years ago reading about a traffic plan system that avoided making intersections, and used only one way roads that fed into each other using over passes and under passes kind of thing. I'm trying to find the term that describes this type of roadway.

It would be like the artery / vein system in the body, where the blood flow is practically one way only.

Thanks

--InverseSubstance (talk) 06:49, 11 May 2012 (UTC)[reply]

Controlled-access highway?--Shantavira|feed me 07:21, 11 May 2012 (UTC)[reply]
Sounds impractical. In addition to the high cost of all those bridges, you'd need a cloverleaf interchange to replace every intersection. Those use up a huge amount of land, concrete, and money. StuRat (talk) 14:54, 11 May 2012 (UTC)[reply]
Well it's the way every motorway junction is designed in the UK! TammyMoet (talk) 20:34, 11 May 2012 (UTC)[reply]
Not Junction 3 on the M50! Tevildo (talk) 11:25, 12 May 2012 (UTC)[reply]
You need to help me with what a "motorway" is in the UK. Obviously, not every road or driveway intersection has a cloverleaf, so are you talking about controlled-access highways only ? If so, that's the same as in the US. StuRat (talk) 02:32, 12 May 2012 (UTC)[reply]
It's not hard to imagine a system of streets that has forks but no crossings. I've seen plenty of districts, typically in city centres, in which all streets are one-way. It's somewhat harder to imagine combining these two features. But intersections and overpasses can both be avoided with roundabouts. —Tamfang (talk) 06:45, 12 May 2012 (UTC)[reply]
Roundabouts don't avoid intersections, they are just another type, with the same problems of having to be extra careful, slow down, and even stop in heavy traffic, with the risk of being T-boned. This can all be avoided with a well-designed cloverleaf. StuRat (talk) 16:00, 12 May 2012 (UTC)[reply]
But what do you do if you live in a Cul-de-sac? SkyMachine (++) 08:28, 12 May 2012 (UTC)[reply]
Of course we have articles on everything: Motorway. This is what a typical motorway junction looks like from the air. This is what a typical motorway junction looks like if you're travelling down it. Note that if you want to leave the motorway you do so from the left-hand lane. --TammyMoet (talk) 09:13, 12 May 2012 (UTC)[reply]
If you're restricting the plans to one-way streets, you only need two slip-ramps (for going from road A to road B and for going from road B to road A, with A and B themselves continuing in their straight directions crossing over/under each other), not the usual of the usual set of eight ramps of a full cloverleaf (between A and B with two directions of travel on each, there are 8 permutations of directional connections between A and B). An alternative is to have A and B merge to form a single one-direction road for some distance and then diverge again. That seems to require more (or at least more specifically shaped) land. But it also might make more driver annoyance overall (*everyone* merges) unless there are lots of outside-edge lanes that do not require merging. Depending on whether A and B diverge from the same side (set of lanes) from which they merged or opposite, there could be an easier flow for drivers switching to "the other" road than for those keeping on "the same" one from which they came (and more weaving for the other set of drivers). A normal ramp configuration is easy to be unimpeded for drivers remaining on the same road but substantial deceleration and then acceleration and merging for those switching from one to the other. DMacks (talk) 18:54, 12 May 2012 (UTC)[reply]
With a properly constructed ramp, you don't have to slow down at all, and there's plenty of time to merge, or sometimes no need to merge, if the ramp becomes a new lane (which then becomes the exit ramp at the next cloverleaf). It's only when they try to skimp that you get tight turns without a slope, requiring you to brake. StuRat (talk) 23:59, 12 May 2012 (UTC)[reply]

WTC[edit]

This may have been answered before, but here are a few questions about the collapse:

  1. Why did they collapse at such a high rate, if it was supposedly by a progressive process?
  2. Why were contents of the office floors completely pulverised as if by explosive force? As noted by a firefighter, the largest recognisable component of any of the many desk phones that are bound to found at the site, was half a key pad. He also noted that the debris of the structure itself was basically turned to dust, instead of the rubble he usualy finds at a scene of a collapsed building.
  3. What was the cause of the explosions in the vicinity of the 8 floor?
  4. Allow me to speculate, is it possible for the towers to have been constructed with built-in demolision explosives?

Plasmic Physics (talk) 12:19, 11 May 2012 (UTC)[reply]

Probably:
  1. Gravity & height. Things tend to get faster the further they have to fall.
  2. What do you expect things to look like when crushed under tonnes of concrete which has fallen from hundreds of feet? How many collapsed tallest ever tower blocks has the fire fighter experience of?
  3. Pass
  4. Possible, yes. Most extremely unlikely. --Tagishsimon (talk) 12:37, 11 May 2012 (UTC)[reply]
You can find discussions of all that and more! starting with our 9/11 conspiracy theories article. --LarryMac | Talk 12:45, 11 May 2012 (UTC)[reply]
Plasmic, you seem like a clever person - how can you be at all attracted to ideas that a second cause is needed after someone flies a jet airliner into a building? I fairly strongly believe that the "9/11 conspiracy theories" are deliberate disinformation, disseminated to push the national discussion away from more realistic conspiracy theories, such as that the Bush administration or intelligence establishment or private companies or somebody paid bin Laden to fly those planes into the towers in order to justify creating a security state with massive spending on unproductive programs. In this way it would resemble the second-shooter theories of the Kennedy assassination, which divert discussion away from whether the Russians or American intelligence arranged with Oswald for the crime. Wnt (talk) 14:34, 11 May 2012 (UTC)[reply]
A conspiracy to create a conspiracy theory - would that be a meta-conspiracy ? Gandalf61 (talk) 14:38, 11 May 2012 (UTC)[reply]
That's a bit silly. Presumably the reason behind that conspiracy theory would be to make money for Halliburton, etc. However, considering that Bush and Cheney were already rich and powerful, it seems absurd to risk losing everything, and gamble on life imprisonment and humiliation, in order to increase their wealth a bit more. StuRat (talk) 14:44, 11 May 2012 (UTC) [reply]
Who said anything about imprisonment? Remember Arms-for-no-hostages? Remember Pat Robertson's support for Charles Taylor (Liberian politician)? This is the kind of stuff these people do, and even if they're caught they get away with it; it's not even an embarrassment except in the sense that they couldn't keep their unmentionables unmentioned. They'd muddy the waters a little, make it unclear whether they were paying to cause the attack or prevent it, the press would call it a scandal for a day or two, and people would move on. Wnt (talk) 16:20, 11 May 2012 (UTC)[reply]
You fail to understand the difference between killing foreigners and Americans. Politicians can get away with the former, but not with killing 3000 Americans, especially the rich ones working in the WTC. StuRat (talk) 16:24, 11 May 2012 (UTC) [reply]
Bear in mind we're talking about over $1 trillion dollars in spending generated by the attacks. That's a lot of money even for the richest people on the planet. So far as I know, there are no trillionaires ... yet. Wnt (talk) 16:32, 11 May 2012 (UTC)[reply]
But very little of that went to the decision makers in your conspiracy theory (Bush and Cheney). And the difference between being a powerful millionaire and imprisoned is a lot more than the diff between being a powerful millionaire and a slightly richer one. StuRat (talk) 16:37, 11 May 2012 (UTC) [reply]
If Dubya made any decisions for himself I'd be amazed. Wnt (talk) 16:55, 11 May 2012 (UTC)[reply]
I'm not a conspiracy theorist, but if you are interested where that money went — and a lot of it did go to people in the intelligence agencies — Dana Priest and William Arkin's Top Secret America book is pretty fascinating. George Tenet, for example, has made quite a tidy amount of money for himself as a "intelligence consultant" to the government in the post-9/11 world, to point out one guy in particular. The revolving door between intelligence/security professionals and high-paid security consultants has been spinning like a dervish since 2001. --Mr.98 (talk) 17:37, 12 May 2012 (UTC)[reply]
Backtracking a moment, I should point out that the existence of a disinformation campaign doesn't require that the allegation being suppressed is true. It is possible that a conspiratorial involvement by U.S. agencies or even by Russia or some other foreign country would become the object of such a campaign simply because it is seen as troublesome. For example, intelligence agencies after JFK's shooting might have wanted to downplay any possible role for Russia simply out of fear that minor politicians would start going on TV and calling for the nuking of Russia and ratchet up tensions to the point where a real nuclear exchange became more likely. Wnt (talk) 17:00, 11 May 2012 (UTC)[reply]
4) Considering that the WTC was built in the early 1970's, why would explosives have been built in back then ? This was long before al-Qaeda existed. StuRat (talk) 14:48, 11 May 2012 (UTC)[reply]
When George Bush designed the buildings in late 1960s, his plan was to be president in 2001. Sandboxer (talk) 15:18, 11 May 2012 (UTC)[reply]
 :-) StuRat (talk) 17:04, 11 May 2012 (UTC) [reply]
Once a couple of floors have let go, the dynamic impact loading so far exceeds the designed static loading capacity of the structure that there is no delay as the mass impacts the next floor. The kinetic energy released is ample to destroy just about everything. How many collapsed 100 (or even 10) story buildings has this firefighter seen?
As to the absurd idea of placing explosives in a building by design, I can assure you that architects and engineers spend their time more productively to assure that buildings protect their occupants (the relevant standard is called the "Life Safety Code"), and that nobody would countenance (or be insured for) such a measure. I'm pretty sure my professional liability insurance doesn't cover demolition explosives, nor did Minoru Yamasaki's. That of course ignores the general absurdity of the "controlled demolition" conspiracy theories, which unquestioningly assume that total demolition of WTC 1, 2, and as an afterthought WTC 7 were an obviously essential outcome, and not trusting that a couple of fueled 767s at high sonic speeds would create a satisfactory commotion, and ignoring that the Pentagon and Capitol weren't similarly leveled, and assuming that this conspiracy extends over decades and reaches into the highest levels. Acroterion (talk) 17:07, 11 May 2012 (UTC)[reply]
I have this theory that it was all caused by a bunch of religious nutters flying planes into buildings. HiLo48 (talk) 22:27, 11 May 2012 (UTC)[reply]
Nah. Too obvious. Remember the conspiracy theorists credo: The obvious explanation must always be discarded. ←Baseball Bugs What's up, Doc? carrots→ 03:51, 12 May 2012 (UTC)[reply]
I would have expected a debris field around the building, with a great many objects tossed some distance from the building, as things collide and columns buckle. and not all ground to powder under the main footprint of the building. Edison (talk) 04:01, 12 May 2012 (UTC)[reply]
I wouldn't. We had no reason to know what to expect. It was a one-off experiment, one we're not likely to reproduce any time soon. It hadn't been done before, and now we know what happens when a bunch of religious nutters fly planes into buildings like that. HiLo48 (talk) 04:16, 12 May 2012 (UTC)[reply]
The towers came straight down, piling on each other, and there were plenty of nearby buildings (at least one of which also collapsed later in the day) to kind of "contain" the debris, so the stuff that was scattered tended to be dusty (and a fair amount of it toxic - asbestos, maybe?) ←Baseball Bugs What's up, Doc? carrots→ 04:43, 12 May 2012 (UTC)[reply]
Many times a tornado will destroy a house and countless small objects go missing, never to be seen again. And that's without millions of tons falling on them. If nothing else, the WTC attacks confirmed that they way they built it, which seemed so nifty at the time, with the exterior being the primary support, was a possibly fatal design decision. ←Baseball Bugs What's up, Doc? carrots→ 04:39, 12 May 2012 (UTC)[reply]
Hmmm, we don't have much to compare it with. For all we know, if it had one major support beam in the middle the terrorists would have taken it down with the van bomb. Or if were a visibly tougher building, maybe they'd have crashed the plane into the Empire State building instead and taken it down immediately with many more fatalities. We're so far out into anecdotal data here, no real experiments possible, it's impossible to say what would or wouldn't have been best to do at the engineering level. Wnt (talk) 23:47, 12 May 2012 (UTC)[reply]
WTC 1 and WTC 2 did not fall straight down in a neat pile. They collapsed on top of a dozen neighboring buildings. One building was an immediate total loss, and several others were damaged beyond repair. The towers did not turn into dust; trucks carried steel and concrete from the site for months. 88.114.124.228 (talk) 15:45, 12 May 2012 (UTC)[reply]
Yes, the surrounding buildings took much of the hit of the collapse (including the building across the street that collapsed later in the day). The dust cloud funneled through the surrounding streets. One thing to keep in mind is that in the cubic volume of any office, typically there's going to be a fair amount of "air". Obviously, when a 100-story building pancakes down, a lot of that air is going to be pushed out, leaving just the solid rubble. ←Baseball Bugs What's up, Doc? carrots→ 18:34, 12 May 2012 (UTC)[reply]
A significant amount (by mass, if not by volume) is also liquid (water in the plumbing, etc.). That would either drain away or evaporate, in short order, after the collapse. StuRat (talk) 23:53, 12 May 2012 (UTC)[reply]
Regarding 3, the explosion on the 8th floor: an emergency responder (firefighter or whatever) reported that he heard two explosions around this floor, so it's very plausible that indeed some explosions happened. The building had emergency power systems, powered by diesel fuel, and that were on separate floors, including the 8th. In the 8th floor there was one 275 gallon tank power generator.
Regarding 4: I'd rather say that lots of people would know it if it were true. There is not only the build-in during the constructing, but you'll have to take care that no one find the explosives during a renovation. OsmanRF34 (talk) 22:08, 12 May 2012 (UTC)[reply]

These conspiracy theories all seem to center around the way the buildings pancaked and crumbled. They assume that the buildings were properly constructed in the first place. My experience tells me that properly mixed concrete does not begin to deteriorate for something like a hundred years. properly mixed concrete tends ,when demolished, to break into large pieces held together with rebar. substandard concrete tends to pulverise when impacted and has little flexural strength. I have not reseached who the building contractors were and I'm guessing it was government funded. It is not unknown for contractors to pocket large sums of money on the back of substandard fraudulent construction. Amongst all the hype,furor and investigation, has there been one word investigating the construction. A scenario like that would certainly warrent some smoke screen from influential freinds.190.56.115.245 (talk) 00:47, 13 May 2012 (UTC)[reply]

The building was designed to 'pancake.' What would you prefer, it falling to any side in a highly populated area? And it wasn't converted into dust (as the conspiracy theorist say). And the issue was not the quality of the construction of the building. It could withstand a small ṕlane crashing, but a full-loaded jetliner is too much to any building. OsmanRF34 (talk) —Preceding undated comment added 12:09, 13 May 2012 (UTC).[reply]
How about this: the experts have said that the steel columns at the core of the building should have halted the collapse, and directed the force outward. Since the building was stronger in the core than toward the edges, the edges would have been falling faster. This should cause the collapse to lose momentum by redirecting falling debris outward instead of mostly downward. In the least, the floors should have pancaked around the columns, the violent vibrations of the bare columns should have twisted the collapsing building off the vertical and dragged it over, instead of it falling perfectly downward. The collision also caused assymmetric damage crosswise, even a small lag in failure would translate into an amplified effect visible further down the collapse. Plasmic Physics (talk) 01:39, 14 May 2012 (UTC)[reply]
Why is it that a demolision takes months to so carefully plan to ensure that a building falls as perfect as possible downward, when in this case it just happens naturally? Plasmic Physics (talk) 01:44, 14 May 2012 (UTC)[reply]
Well, a demolition doesn't want a building to probably fall perfectly downward! 9/11 shows that they managed to fall straight down on their own twice, but nobody knows what would happen on a third try. More to the point, the collapse of a very tall building will tend to be qualitatively different, because the downward force and moment of inertia is so much greater. Maybe if the fire burned away one whole edge things would have been different, but with everything failing more or less at once as whole floors were on fire ... it probably tends to be pretty symmetrical. Wnt (talk) 03:58, 14 May 2012 (UTC)[reply]
A controlled demolition would need to be a lot cleaner than that, or they would all be sued for the damages to the nearby buildings. Note that the same design features which keep buildings from falling over sideways while intact also work (somewhat), when the building is no longer intact, to keep the debris from falling over sideways. StuRat (talk) 04:11, 14 May 2012 (UTC)[reply]
If it was a covert demolition, then it would be kept out of the books and no one could be sued; there needs to be a balance between minimising collateral damage and maximising believability. I don't quite understand your second statement. Plasmic Physics (talk) 04:26, 14 May 2012 (UTC)[reply]
It's a question of stability. Let's consider an unstable design, like an inverted pyramid. That might very well fall over sideways, either while intact or when demolished. StuRat (talk) 05:26, 14 May 2012 (UTC)[reply]
That's not making sense - it does not take into account the assymetrical damage to the design. Plasmic Physics (talk) 06:06, 14 May 2012 (UTC)[reply]
When a ship sinks, the design that kept it unright while afloat does not neccessarily keep it upright while it sinks. Ships often list as they sink. Plasmic Physics (talk) 06:09, 14 May 2012 (UTC)[reply]
A ship with damage to one side fills with water on that side, which can weigh more than the ship. Not so with buildings. StuRat (talk) 06:46, 14 May 2012 (UTC)[reply]
A building with damage to one side weakens on that side, which can collapse before the other side. Plasmic Physics (talk) 07:08, 14 May 2012 (UTC)[reply]
Ah, but was the damage to one side? It would be one thing if a few floors of the WTC were two huge auditoriums, and one was full of plane and jet fuel while the other was empty. Then you'd expect the beams on one side to bend and give way, and the other to stay firm. But in truth, the jet fuel poured all over, some even flaming down the central elevator shaft AFAIK. It was more or less evenly distributed. Then the heat builds through hundreds of degrees, and the whole floors caught in flame (as the pattern of smoke indicated). The heat then increased much hotter than that. So it was a very uniform heating throughout the entire floor, not one calculated to put a strong push to send the top one way or another. And remember, the top had a huge amount of push going straight down - and no force at all to make it turn and flip sideways. Where would all that force come from to whirl around a fair-sized skyscraper (which is what the top of the WTC is) and to do so in only a few seconds or less between the time when it held firmly and when it had totally given way? Wnt (talk) 20:42, 14 May 2012 (UTC)[reply]
Columns closer to the impact zone should have collapsed before the columns further out, perhaps miliseconds apart. Much like a zipper effect. Even a small time difference between one side of collumns collapsing before the other, would cause a torque effect. Gravity v.s. a small support force acting around a fulcrum should produce a twisting, meaning most of the debris should fall off one side. Plasmic Physics (talk) 23:28, 14 May 2012 (UTC)[reply]
Well, here's the root of the problem: I don't see it that way at all. The sideways force shouldn't exceed that of gravity (shouldn't come near it, really) and milliseconds aren't enough time for gravity to move the building significantly. By the time it starts really moving ... it's moving down. Wnt (talk) 19:44, 15 May 2012 (UTC)[reply]

You're all repeating a common falsehood: the south tower did not fall straight down (watch for yourself); it fell a long way to the left (in that video.... I think that's eastward). Makes a lot of sense, since that's the side the plane hit the tower on.-RunningOnBrains(talk) 02:01, 16 May 2012 (UTC)[reply]

But I guess that doesn't matter anyway. 9/11 "truthers" (BIG emphasis on the quotes) are all about distrusting the man/government/illuminati/whoever they think runs the world. You can poke a thousand different holes in their "theories", but they'll just adapt it and cherry-pick their evidence to find some way that the official story doesn't quite add up. Just like the "where's the plane" Pentagon garbage (fyi, it's right here), anyone who takes an honest look at all the facts would see that no other explanation than the official one makes even a small amount of sense (I'll allow for some slight plausible variations, like there were insiders in the government helping it along, but even that seems highly unlikely).-RunningOnBrains(talk) 02:11, 16 May 2012 (UTC)[reply]
(edit conflict)I didn't say that there was a sideways force. The miliseconds between one side of the building and the other side is what is most important, not the difference between individual columns.
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Plasmic Physics (talk) 02:37, 16 May 2012 (UTC)[reply]

What about the other scenarion I described above?
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|||||||||       |||||||||      ..--H-H--..      ...H.H...       ...H.H...          H H
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Plasmic Physics (talk) 11:39, 16 May 2012 (UTC)[reply]

Both your scenarios diagrammed above are what I would call "falling straight down" As Runningonbrains put it, the one tower fell "a long way" to the left. Maybe relative to a house trailer, yes, but relative to the size of the building? That's what I call "practically straight down". Same as your little particles in the first cartoon. Where do you think they're going to go, sailing away into the sunset, finding a building even further than WTC 7 to land on? No, they're going to do what isolated bits of stuff hanging over mid-air do, which is to fall down. Wnt (talk) 19:26, 16 May 2012 (UTC)[reply]
Agreed. If you consider how fast a particle would need to be moving sideways, even in a vacuum, to go, say, the height of the building sideways before hitting the ground, it would be a very high speed. Once you add the effects of wind resistance, collisions with other falling particles, and collisions with nearby buildings, going that far sideways becomes even less likely. StuRat (talk) 23:31, 16 May 2012 (UTC)[reply]
The second scenario supposes that the momentum of the collapse is redirected outward, effectively losing strength in the downward direction, halting the collapse. This should result in a pencil point.
As a reminder: these are not my scenarios. Plasmic Physics (talk) 01:41, 17 May 2012 (UTC)[reply]
Read Collapse_of_the_World_Trade_Center#The_collapse_mechanism, then come back if it still isn't clear. -RunningOnBrains(talk) 01:55, 17 May 2012 (UTC)[reply]
That is exactly the mechanism that is being contested. Plasmic Physics (talk) 02:59, 17 May 2012 (UTC)[reply]
It explains quite clearly why your scenarios don't make sense. Even a single floor collapsing imparts forces 30-times the static force on the floors below, more than enough to progressively buckle the entire structure quite quickly. To be honest you've made such varying claims throughout this thread that I don't even know quite what you're arguing anymore. You make vague claims about "the experts" saying this and that but it's all heresay, and I doubt it is even partially true.
It is completely ludicrous to assert that the towers fell in any manner than has been already described in detail. Do you actually have a question? Or are you just trying to get the last word in this discussion?-RunningOnBrains(talk) 03:42, 17 May 2012 (UTC)[reply]
It does not explain the second scenario. You're missing the point, progressive buckling ignores the design of the building. I'm asking why it should make more sense than the second scenario. Plasmic Physics (talk) 04:26, 17 May 2012 (UTC)[reply]

Transitional relativity ?[edit]

Hello,

does someone know if "transitional relativity" exists outside of Star Trek ? If so, what is it anyway?

Thank you. 194.199.79.181 (talk) 13:30, 11 May 2012 (UTC)[reply]

I can find no reference to 'transitional relativity' in science that does not relate to that single throwaway Star Trek gag, save for one book review that appeared in Nature in 1969: [4]. In that instance, the term is not being used to describe a particular branch of relativity, but simply to describe the type of textbook. That is, it is a textbook about the theory of relativity that attempts to bridge the transition between the way the subject is taught in (secondary, or high) schools and the way that it is presented in universities; it is the textbook that is transitional, not the relativity.
Additionally, there are a few references to 'transitional relativity' in contract law. TenOfAllTrades(talk) 15:15, 11 May 2012 (UTC)[reply]

Digging to Vesta's iron core[edit]

I just read that Vesta has an iron core with radius 107 to 113 km [5]; the protoplanet has overall dimensions of "572.6×557.2×446.4 km" as our article summarizes this (I can't access the original report at the moment, despite how much the taxpayers paid for this probe...). So depending on circumstances it is possible that a 100-150 km hole down into Vesta might get you to the very boundary of a frozen iron core. Vesta has about 0.022 g gravity (somewhere...) so the pressure at that depth would be something like a 2 km hole on Earth, which is to say, survivable. Whether there's a hope for some Krubera Cave with a correspondingly greater depth, going all the way down to the core boundary, well... in sci fi there may be. ;) And admittedly boring a 100 km hole, no matter how low the gravity, would be awfully ambitious for the human presence in space.

Nonetheless, suppose we could get down to this frozen core boundary. What would we find? Would there be big chunks of exotic mineral ores that are lighter than iron but heavier than all normal rock? Fields of diamonds like something out of Clarke's Jupiter? Maybe even liquid water and life, pressurized by the vast downward distance and heated by residual radioactivity? Wnt (talk) 18:39, 11 May 2012 (UTC)[reply]

Just as a note, Science (the journal) is a private company, that's why you can't access it, but you should be able to arrange a copy through your local public library, or if not any local university probably has access. Also all data collected by government-funded missions like NASA is in the public domain, so if you wrote them asking for data you could get it (although it might be a bit overwhelming if you didn't know what you were looking for). If you want to complain about access to scientific data, try dealing with the Europeans...they're heartless bastards who keep their science under lock and key. America is pretty much the only country in the world where scientific data is freely shared. -RunningOnBrains(talk) 19:50, 12 May 2012 (UTC)[reply]
Even if it was packed with diamonds the cost of returning them to Earth would be far more than they are worth. This is especially true since we can create diamond in labs these days. StuRat (talk) 21:29, 11 May 2012 (UTC)[reply]
Oh, I know - especially diamonds, which are overvalued - but it could be a pretty visual image. I'm wondering what is down there, whether it's anything special. But Actually, based on how diamonds form, I suppose it's very very improbable, since the pressure needed is actually greater than Vesta could manage, I think! Unless they formed during some past collision and sank when it was molten or something, but then, I suppose they'd be microscopic, and they wouldn't sink anyway. Wnt (talk) 02:10, 12 May 2012 (UTC)[reply]

Cobra Mist[edit]

Have there ever been plausible suggestions for the cause of the Dopler-shifted noise that hampered and ultimately led to the shutting down of the Cobra Mist over-the-horizon radar system in 1973? And did this system cause the same interference as the Russian Woodpecker (and if not, why not)? The transcript of the report "The Enigma of the AN/FPS-95 OTH Radar (U)" can be found here, second half of the page. (It's a UFO site, but the transcripts seem genuine, the source in the Cobra Mist article only has the odd numbered pages). Ssscienccce (talk) 20:11, 11 May 2012 (UTC)[reply]

Not specifically about that radar, but noise is a common problem with all radar. In particular, things like water vapor droplets or flocks of birds close to the radar show up as much as large objects far from the radar. This problem is usually solved by attenuating the signal returned from nearby objects, so they once again are in proportion to returns from object far from the radar. I don't know if this was done with the Cobra Mist system. StuRat (talk) 21:27, 11 May 2012 (UTC)[reply]
Using pulsed wave signals, reflections from nearby objects would be filtered out on a timer basis. The main problem was the amount of ground backscatter, given the long distance the signal traveled (1000 to 3000km), it would receive the ground reflection of an area of maybe 1000 km2, while a typical target would present a surface area of only 30 m2. The pulse Doppler radar signal processor was required to suppress the ground backscatter by 85 to 90 dB relative to aircraft returns; for that, the transmitter and receiver were designed to have a very large linear dynamic range. Basically they depended on accurate doppler shift filtering to remove the ground backscatter, but for some reason the received signal contained a lot of noise in all the doppler shift ranges. It was as if they received signals from thousands of targets all traveling at different speeds. I found this document suggesting the noise could be due to range-discrete meteor echoes or to range-dispersive auroral scatterers. They conclude: The spectral behavior of the meteor-nose echo agrees very well with that of the FPS-95 noise. Theoretical tenets as well as experimental evidence force the conclusion that the FPS-95 noise is produced in part by meteor-nose echoes. However, it doesn't explain why the phenomenon was seen only over land, not over water, and the writers of the "Enigma" paper do not accept this conclusion. Ssscienccce (talk) 14:06, 12 May 2012 (UTC)[reply]
What is it that is constantly moving in large volumes over land, and never over sea? Why, road traffic of course! A single truck could be large enough to produce a detectable echo. On freeways and highways, you get clumps of vehicles moving together, and together they could be a large enough target. As traffic cops using radar know, when you have two directions on a road, you can get echos aparently indicating speeds that are multiples of the true traffic speed, as the bean refects from one vehicle to another, adding the speed of each. Please tell me that folks who spent vast sums of money knew this, and dealt with it somehow. Or have I missed something? Keit120.145.7.207 (talk) 12:51, 13 May 2012 (UTC)[reply]
That's a sensible answer! We can't have those! Space aliens are far more likely! Tevildo (talk) 16:45, 13 May 2012 (UTC)[reply]
Good point, they don't mention that in the report. Maybe the timing of the noise or the calculated speed wasn't consistent with ground targets, I don't know. Looking at the graphs in the report, the noise levels peak before and after the ground backscatter, maybe that's why they think it must occur when the waves reflect against the ionosphere. I must say their initial expectations were a bit high, there was talk about maybe later, if all went well, increasing the range with a second bounce of the ionosphere. Not sure if they meant ionosphere-ionosphere-target or ionosphere-ground-ionosphere-target ... Ssscienccce (talk) 21:17, 13 May 2012 (UTC)[reply]

Eating pearls[edit]

Are there any health benefits or risks involved in swallowing pearls? For example, if one is embedded in an oyster and swallowed by accident.

Also, how hard is a pearl? Would biting on one be more likely to break the pearl or a tooth?

(I tried to search for a reference desk item that is relevant to the health question. Got some about Pearl Harbor and "pearls before swine" but nothing relevant.)

Thanks, Wanderer57 (talk) 21:01, 11 May 2012 (UTC)[reply]

You could choke on a large pearl. If you manage to swallow it I'd expect it to be dissolved by stomach acid. I'd also expect it to break before your teeth, possible leaving sharp bits that could cut you. StuRat (talk) 21:19, 11 May 2012 (UTC)[reply]
If you drink a goblet of wine in which a pearl has been dissolved, make sure you know the motives of the person who dissolved it. --Trovatore (talk) 21:46, 11 May 2012 (UTC)[reply]
Pearl is 2.5 - 4.5 on Moh's scale of hardness, which is pretty soft. Made almost entirely of calcium carbonate and thus readily dissolvable in the digestive system as stated above. If you have swallowed it then the risk of choking is virtually zero. I can't agree that there are any health benefits or dangers. Richard Avery (talk) 08:09, 12 May 2012 (UTC)[reply]
Well, the record seems to show that it is very hazardous, if the provider of the pearl killed your father, his brother the king, and took over your father's throne and queen. Although in that situation you also need to watch out for poisoned rapiers. --Trovatore (talk) 21:54, 12 May 2012 (UTC)[reply]
Drinking pearls dissolved in wine or vinegar seems to have been a well-known (if rarely done) act of ostentation. Cleopatra performed the trick to impress Anthony.[6] Caligula was another pearl drinker, and Sir Thomas Gresham is said to have ground up and drunk a pearl worth £15,000 to impress the Spanish Ambassador according to this source or in drinking the health of Queen Elizabeth I when she visited his new Royal Exchange according to Brewers. Alansplodge (talk) 09:01, 12 May 2012 (UTC)[reply]
The Mohs scale is a measure of scratch hardness (that is, you can tell if your teeth will scratch the pearl or vice-versa). If you want to estimate the odds of damage to your teeth, you want an indentation hardness test or you want to compare the relative compression strengths (or, given the leverages and directions of force involved, you might need to factor in tensile strength). --Carnildo (talk) 01:42, 16 May 2012 (UTC)[reply]
Typically, a pearl is wrapped around a bit of sand from the bottom of the ocean. If that's something you want to consume, knock yourself out! ←Baseball Bugs What's up, Doc? carrots→ 14:46, 12 May 2012 (UTC)[reply]

It could perhaps help digestion as a stomach stone. Count Iblis (talk) 02:18, 13 May 2012 (UTC)[reply]