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December 27[edit]

Lack of Visual 'Imagination'[edit]

I am unable to "visualise" anything. If I close my eyes, I see only the back of my eyelids and have never been able to summon an image.

And whilst I very rarely dream (or remember them as I'm sure people will claim), the very few I recall having have not had any pictures, but more like reading a story -- I know what is happening but not in pictures.

This has always been the case, though I only realised when I was a teenager that when people said "visualise" they were being literal and could actually see pictures in their head!

My question, is there a name that describes this psychopathology, and is it a common thing? Any studies regarding this and how it relates to creativity and inteligence? Is it perhaps an autistic spectrum disorder?

This facet of myself does not worry me and any information will not be taken in any way as medical advice. So any pedants can please leave other more useful responders free to speculate.

86.132.225.66 00:35, 27 December 2006 (UTC)[reply]

Who knows — maybe dreaming is more 'pathological' than not dreaming! At any rate, I do not recall learning about this or any similar condition while studying psychology.

Dreams serve to enlighten and evaluate, so perhaps a lack of dreaming, or lack of visual imagination, is a good sign that you are already quite enlightened, open-minded, free of social bias, and so on. Vranak

I've had colleagues who were not "visual thinkers," and their understanding of science was entirely verbal. Perhaps they lacked the ability to see pictures in their heads? By analogy, I've heard about people who can play actual music in their heads, whereas I'm more limited and can only remember how a tune goes but not hear instruments playing it. I'm definitely a visual thinker, but when I see a picture in my head, it's nothing like an image on my retina. It's more like a memory. If I visualize a dark background with a square made of glowing green lines, I can't exactly see it, instead it's more as if I'm remembering what such a vision looks like. I can make this green memory-square shrink and grow, rotate, change colors, etc. But it's only as detailed as a fuzzy memory, and if I try to add too many details to this vision, I'll lose track of some of them. On the other hand, I've heard of visual thinkers whose internal vision is just as accurate as reality, and who can build incredibly detailed objects and then continue to "see" them. If visual thinking can range up to that high ability, then it probably ranges down to where it's so fuzzy that it becomes useless. --Wjbeaty 04:36, 27 December 2006 (UTC)[reply]

Although "imageless dreams" are regularly reported, this is the first time I hear of someone who otherwise has normal vision only having such dreams. Most people report having at least occasionally dreams that are visually as vivid as they experience the world when awake. In contrast, visual imagination is normally not reported as having a quality of vividness, in accordance with Wjbeaty's comment, and neither is visual recall of a familiar image. From the scant reports on people with vivid visualization, it is not clear whether this is coupled for imagination and recall. The usual lack of vividness of recall is in marked contrast with the ability of many people to have a vivid recall – often involuntarily – of sounds and in particular melodies. But most people are unable to "imagine" a new melody. Apparently these various abilities are not tightly coupled. --Lambiam ^Talk 10:15, 27 December 2006 (UTC)[reply]

If you are really unable to visualize at all, that would be very interesting from a cognitive perspective. You might offer yourself up to a university for some MRI scans — I have a feeling cog sci graduate students would be very interested in seeing how your brain looks, whether or not the visual centers look the same as other people's. Because even blind people can usually visualize, because they still have the same brain hardware as the sighted. It's very, very interesting that you cannot, though you can still see fine? It is very curious. --24.147.86.187 14:24, 27 December 2006 (UTC)[reply]

This is why I was asking, if it is a recorded phenomena then perhaps there is some research into it, and it has a name. Alternatively perhaps there is a spectrum between people who can see images as clearly as if they had their eyes open (which I've heard people claim), and as Wjbeaty said down to a fuzzy near useless level. Could anyone tell me the field of study this is? Or even the name for this sort of ability, "imagination" sounds rather vague.

I also can not hear sounds either (unless from my ears), but this seems more common. Some people, musicians for example, do claim they can hear a tune in their heads.

Another example from my strange mind :) I am reasonably poor at recognising faces (this does have a name which escapes me at the minute, but I'm not incapable in any case). If you asked me to describe someone I can't "see" them, but I just "know" that "A has short brown hair, big nose, and pointy eyebrows", as if I had read it some where, and if I want to feel confident about recognising people in future I will consciously remember these features as a list like that.

Incidentally, I did have, 17 or so years ago when I was 8 or 9, CAT scans and EEGs looking for something I wasn't clear about. I was a very quiet child and I think Autism was suspected, but nothing conclusive was found AFAIK, and doubt anyone would now think I was Autistic. 86.133.203.195 00:11, 28 December 2006 (UTC)[reply]

Did you try painting the back of your eyelids - if not, just imagine! -- DLL ^{.. T} 18:31, 27 December 2006 (UTC)[reply]

86.133.203.195, can you draw a room that you're not in right now? Is your drawing accurate? If so, you can visualize things, because there's no way you can make an accurate drawing using only a worded description. --Bowlhover 07:50, 28 December 2006 (UTC)[reply]

To expand on the previous comment, can you draw a room that you are not in currently? Also, have you ever hallocinated? You may want to try going into a sensory deprovation chamber.--Acewolf359 16:23, 29 December 2006 (UTC)[reply]

Wow, looks like it has been sometime since anyone looked into this. I however am very interested as I am in the same situation. I did not realize people could acutally 'visualise or picture' anything, I thought it was just a term people used, I just asked my husband if he could actually see things last year (I'm 36). I was very surprised to find out that people can actually SEE things, my son claims he can even see with his eye's open and makes a game of it sometimes when he is bored. I do however see images in my dreams. I have not been in a sensory deprovation chamber however I have sat in a dark room on a winter night where there was nothing to been seen or heard and all I saw was black. I can draw a room for you but it is not being seen by me I just remember where items are at, it is more like someone is reading the information to me. Is there a term for this? Thanks- Tink

Is red and pink coral illegal in Canada?[edit]

Hello,

I recently was caught by surprise at seeing some beautiful red coral and silver jewellry pieces in a local ethnic gift shop. I have never seen red coral jewellry before in Canada (but I haven't searched extensively!), and for some reason I have always thought it was illegal. Upon questioning the salesclerk, she answered that it was not illegal as the coral was already dead before it was obtained for use in making the jewellry.

1. Are products made from red coral illegal in Canada? 2. Is one being ecologically ignorant in wearing jewellry with red coral?

Thank you! 74.115.30.54 01:11, 27 December 2006 (UTC)[reply]

First, the argument that "it was already dead before it was obtained" is bogus. If the store sold you something that was illegal, the next thing they'd do is order another one, which someone would kill, and then it too would be "already dead". The idea of such prohibitions is to stop the dealing in such products in order to remove the motivation for the killing.

It appears that there is no specifically Canadian law about coral products. Canadian federal laws can be read and searched at the Department of Justice web site, and their search finds nothing containing the word "coral". However, that doesn't make it legal. Canada is a signatory to the Convention on International Trade in Endangered Species, and several species of corals are regulated under this treaty. I have no idea whether there are any red corals that do not fall under CITES and whose sale is therefore legal.

--Anonymous, December 27, 02:18 (UTC).

I assume the clerk meant that the coral had died, not from the actions of those collecting it, but from something else previous to that time, like pollution, for example. I believe tusks collected from elephants which died of natural causes can also be sold legally in some places, but there is a certification process used to prove that this is, in fact, the case. I'd expect something similar for coral. On the plus side, such a program may serve to satiate the demand, thus reducing poaching. StuRat 13:26, 27 December 2006 (UTC)[reply]

I don't know anything about why red/pink coral may be illegal in Canada, but why must you be ecologically ignorant from wearing coral? Endangered species in the United States can often be found to be plentiful in one area, and almost gone in the other (thus they are endangered, there). What if red coral is plentiful some other place in the world? Just being skeptical! It is my understanding that coral is fairly plentiful, and not that tough an organism (small salinity changes or temperature changes, or water current changes can severly stress it), even though the volume makes up for it. Correct me if I'm wrong about that. X [Mac Davis] (DESK|How's my driving?) 22:39, 27 December 2006 (UTC)[reply]

Canada's Species at Risk Act / COSEWIC mainly deal with Canadian species. However the CITES convention, which Canada has ratified in 1975, lists two coral genuses in Appendix II, meaning trade is restricted because they may become threatened by trade (although not currently threatened) or look like threatened species: Fire corals (Milleporidae species), and Lace corals (Stylasteridae species). So you probably don't want to be doing trade in corals of those genuses cause they would be bad. Judging from the name, fire corals are probably red. Note: fossils are not subject to the provisions of the Convention. —Pengo ^{talk · contribs} 06:45, 28 December 2006 (UTC)[reply]

Also I don't recall ever seeing a dead coral that still has its colour. Is it possible that the coral was dyed? —Pengo ^{talk · contribs} 06:56, 28 December 2006 (UTC)[reply]

Many countries whose waters contain living reefs have laws regarding the harvesting of coral, (of any color), and even stronger laws regarding it's removal from the country. Coral that has any color left in it was harvested directly from the reef or found very soon after a trauma, (boat, diver, storm, etc...). This doesn't necessarily add up to illegal coral, if it is in fact real coral at all, but it's not likely to be on the up and up.Oons

skins compression clothing[edit]

I was wondering what effects the use of skins compression clothing have on athletes in terms of both performance and recovery. I was also wondering what is the difference between skins and other brands on the market

muscles[edit]

Is it harder for asian males to get lean muscles through weight-lifting compared to other races?

I don't know an answer, but this is related to somatotypes. I do not believe one can look at it by race very well, however it is possible that different somatotypes are found in different magnitudes in different races? Many scientists argue the existance of "races." Don't worry, we still believe in marathons. X [Mac Davis] (DESK|How's my driving?) 22:34, 27 December 2006 (UTC)[reply]

Science name[edit]

What is the name of the science that deals with the size and shape of the Earth? My sister got asked this, and didn't know. I'm just interested! --Thelb ⁴ 09:04, 27 December 2006 (UTC)[reply]

Planetary science (aka planetology)? Clarityfiend 09:13, 27 December 2006 (UTC)[reply]

Geology ? (or surely one of the many links at the end of the article) -- WikiCheng | Talk 10:01, 27 December 2006 (UTC)[reply]

Geodesy? Weregerbil 10:48, 27 December 2006 (UTC)[reply]

Ding! Ding! Ding! We have a winner. Clarityfiend 11:29, 27 December 2006 (UTC)[reply]

What was a man able to withstand of wounds and injuries during the past (medieval times)[edit]

hey there 'Wikipedia-people', your doing impressively well with this site. I love it =D

I have questions about how much would a man be able to withstand in the past when it came to wounds and injuries from melee-weapons and effects from extreme cold in the medieval age.

i realize that what i am about to ask might seem very strange questions, so to take away any curiousity around it if any, I just say i'm writing a book/novel and so i need facts about this and that, and i use Wikipedia a lot as a source of information, and i realize my questions may not have direct answers, but rather 'guiding' answers that points me in the right direction. If you have any idea at all, that is.

1) A man who takes a axe-cut across for example his hip-bone so strong that his hip-bone are broken/crushed and that his skin and flesh are sliced open to a big open wound, blood flowing out of it quite good, would he stand any chance of survival ? in the past, i take take it they had no methods of 'fixing' broken body parts, like we have today when we go through surgery and such. but would he die in just minutes, or would he die a slow lingering death that stretched for over days ? Would he fade slowly and eventually 'fall to sleep' relatively peaceful due to blood-loss or would there be chances that he died by the injuries itself first ? or would it be chances to save him ?

2) Say that this axe-wound was made out in the wild, in arctic, cold and harsh lands far away from civilization. If there were forexample -15 degrees or even colder, would the cold have ANY impact on 'freezing' the wound and stopping the bleeding on such a big wound ? any impact at all? if any, then HOW strong impact? would it help keep pressing cold snow over the wound ?

3) how big and bad could a wound be before the cold no longer could HELP stop the bleeding from it?

4) what methods did they normally use to treat battle-wounds and stop bleeding ? forexample a an arrow-wound or a lesser sword-sting or lesser sword-slash?

5) If one falls through the ice and into the water, and then gets up on land relatively quickly how long would you be likely to survive in the wild with temperatures as low as -15 or lower? a few minutes, right ? ofcourse, one would have to tear of all clothes in a hurry, as the cold and wet clothes will only add to make you frozen. But then what ?

6) was it possible that a bludgeon-weapon (war-hammer, mace, morning-star, flail, club etc.) could kill a man THROUGH leather, mail or steel-armor in ONE blow ?

if these questions fits better under "culture", since its from the past, just say and i'll put it there instead, but here stood "physique" so...

thank you, Krikkert7 10:58, 27 December 2006 (UTC) Krikkert7[reply]

I can't answer all your questions, but I can answer some. First, people in olden times have survived remarkable injuries; Samuel Pepys had a gallstone taken out without any long-term ill-effects; the son of a mediaeval king (sorry don't remember his name) had an arrow painstakingly removed from - I think his head - and lived, but of course, on the flip side, many many people died of injuries that would be easily treatable today. I think it was King Richard the Lionhearted who died of a fairly minor (well, serious but not mortal) shoulder injury.

As to your first question, even nowadays with fast and efficient medical care, people die of injuries to the femur, even with the skin unbroken; it would be unlikely that your medieaval hero would survive. The speed of his death would depend on whether or not the femoral artery was nicked or collapsed as a result of the injury; if yes, death could be in 10s of minutes or sooner; if no, then he would die of gangrene or shock.

As to cold and injury, cold is seldom good for any serious injury, particularly those that involve blood loss, because it hastens shock, the depression of the cardio-pulmonary system, blood flow and blood pressure that results in unconsciousness, heart failure, organ failure, and ultimately death. The only good field treatment for serious, bloodletting injury is compression, and I am sure many mediaeval warriors knew this.

I hope others can expand upon my answers and answer your other questions. Anchoress 11:19, 27 December 2006 (UTC)[reply]

Interesting questions. I'll try to give some answers. Know this is just speculation, (although intelligent speculation i'd hope).

1. The person would probably faint from the pain. The most immediate way this man would die is from blood loss. An axe-cut that deep would cause a LOT of blood loss, with the person dying in minutes-hours depending on the exact location of the cut. The Axe Cut could easily have damaged his internal organs, or the broken bone could have stabbed up and damaged his internal organs. The next biggest concern is infection. If he doesn't die immediately, the wound will most likely be infected. There're ways to prevent infection (salt, alcohol, burning), but none of these are all that reliable. With no antibiotices, he'll die in days-weeks depending on how big the wound is. So for chances of survival - i'd say very low. Although it does depends on where exactly the wound is and how serious it is. Even if the man miraculously survived on his own, you can be sure he'll never be able to walk or even stand again with a hip bone that badly damaged. Even so, he probably won't survive more than a few years.

2. I'd say the person would most defintely die in those conditions. The cold would 'freeze' the wound, stopping bleeding and halting infection. But...-15 degrees is VERY cold. THe axe cut would also rip of clothing, exposing not only the wound but the entire body to the cold. Being exposed to -15 degree whether causes a whole lot of problems, as Anchoress has already described above.

3. depends on how cold. If we're talking -15 degrees...i'd say the blood would freeze pretty quick - no matter how big/bad the wound is. But in that kind of temperature, the person would die anyway from the cold.

4. you mean with modern medicine? Well...i don't think many people get such battle wounds these days. I'd guess they'd deal with arrow-wounds the way they deal with bullet wounds (so surgically remove the arrow, stop bleeding, antibiotics to prevent infection, stitching...etc.). Back in the medieval times...dunno. HIstory was never my thing. But i'd guess it'd be just a matter of pulling out the arrow, and bandaging it and hope it stops bleeding. If the wound was very bad, they'd probably use this technique that involves basically burning the wound. There's a special word for it but i forgot. I'm not sure how it works, but it's supposed to stop bleeding. Salt/alcohol/heat would be used to kill bacteria, and hence prevent infection. Then the person would just have to rest, and hope his body can make it.

5. if the water was -15, then someone falling into it won't be able to climb out. It'd send you into shock - both phyiscally and mentally. You try jumping into a pool of cold water on a cold day without preperation, and see how quickly you can get yourself out. plus, climbing out of the ice is not easy. That's why so many people die from skating on frozen lakes/rivers - because they fall in and can't get out. I mean, if you fall through the ice, you'd be falling through a small hole. Climbing out is not so easy. Just think about how you climb out of a swimming poll without using the ladders. Then imagine doing that in -15 degree water, with slippery ice. And...can this guy even swim?

6. yeah. If you hit hard enough and at a vital spot. You get hit on the neck/head with a bludgeon-weapon that's swung right...and you'll die. Leather doesn't offer much protection. Not sure about mail or steel armor. But from my understanding, armor protects more against slashing weapons. it's like...when a bludgeon weapon hits, the force of the blow will push you back regardless of armor. So if it's swung with enough force, i don't see why it wouldn't still be able to damage/kill. I doubt the armor can absorb that much shock - a clear hit would kill the person, especially if it's in a vital spot.

--`/aksha 11:53, 27 December 2006 (UTC)[reply]

The biggest difference between then and now is the risk of dying from infection. They would have been perfectly capable of preventing most infections, by cleaning the wound (say by pouring whiskey on it) and by only wrapping in sterile cloth (say by boiling the cloth), but didn't know that wrapping the wound in old dirty rags would cause an infection, so were likely to do more harm than good. StuRat 13:20, 27 December 2006 (UTC)[reply]

If the water was -15 degrees (F or C) it would be frozen solid, so he would not fall into it. (perhaps onto it). People up until the 1930's when sulfa drugs were introduced and the 1940's when Penicillin was introduced often died of very minor infections, despite the best medical care. The son of President Calvin Coolidge got a small blister from a tennis shoe which got infected and he died despite all available medical science. Yet a few hardy souls survived amputations, penetrating wounds of the head in which a steel bar passed all the way through the brain, Phineas Gage (1848) and wounds which left an open fistula into the stomach Alexis St. Martin (1822). Edison 17:19, 27 December 2006 (UTC)[reply]

For the record Pepys' surgery continued to degrade progressively untill he died and may have had something to do with it. 68.39.174.238 04:55, 2 January 2006 (UTC)[reply]

What was a man able to withstand of wounds and injuries during the past (medieval times) - PART 2[edit]

Hey, THANKS LOTS FOR UR ANSWERS on my previous questions!!! ...but now you got me going for more with all those good answers :D :P

Ur very helpful to me!

7) As for the the guy falling in the water, i was thinking more like he got help from some mate/friend who drags him up quickly. i understand he would still go in shock, and die HOW FAST??? how would the process go about ? would he sit quite unmovable, shaking ? not able to speak, and in shock as said? and eventually his body would not be able to take it anymore, and he would FADE SLOWLY ? or would it all happen more quick and brutal ? i guess his friend would do him a favour by ending his misery quick... :S

8) And quite interesting i think, how would this guy who pulled him up fare ? how would his arm and hand fare ? (Ofc, his hand has to be put into the icy water and get wet to pull his friend up - say he's quite strong and able to do so with only one arm) I take it chances would be BIG for him to be hit by frostbite, or maybe he would be WITHOUT ANY DOUBT in such a harsh climate? At least his fingers and hand would be greatly in risk, no ? However, if he quickly dry the arm and hand as best he can with something dry and then wraps arm/hand in as much cloth he can to generate warmth, he may be able to "recover", no ? - even though they are out in the wild with extreme cold...

9) And.. as I know, if frostbite gets to bad, and gets infected or is hit by gangrene, one has to amputate the limb/bodypart that is infected. i tried read about amputation ( in the past) but found nothing about how they stop the bleeding... i mean, if u forexample saw of someone's leg or arm, HOW ON GODS GREEN EARTH are you going to be able to stop the bleeding from such a big open wound? the blood must flow out in less than a minute ?!?! :O i read scarcely that they lingate the main arteries and veins BEFORE the 'operation', but they didnt do that in the past did they ? and how would they be able to do that before they had sawn the leg/arm of ?

10)you say extreme cold is bad for any big wound, and i guess i see the logic in it. the cold goes straight INTO your body through that huge open wound i guess and chills down/cools down and kind of freezes your INSIDE, affecting inner organs and all that much much faster. but you did not give me an opinion on how fast he would die when counting'in the extreme cold. so... ?

thank you Krikkert7 14:48, 27 December 2006 (UTC) Krikkert7

Lipitor and grapefruit[edit]

How dangerous is eating a daily grapefruit while on the lowest dose of Lipitor?

We really can't tell you how dangerous it is, but you should avoid it, as grapefruit causes many meds to stay in the system longer than usual and thus have more of an effect than usual. Of course, if this effect was predictable, just reducing the dosage of Lipitor would solve the problem. Unfortunately, I don't think anyone has studied it to know exactly what the magnification factor on Lipitor is, so any reduction in dosage would be little more than a guess, therefore I would just avoid grapefruit, instead (which is a shame, because grapefruit is really good for you). Perhaps we can get the gov to fund a university study ? StuRat 13:07, 27 December 2006 (UTC)[reply]

There have been many such studies. Lilja JJ, and co-investigators ( Clin Pharmacol Ther 1999; 66: 118-27) found that grapefruit juice increased Lipitor's availabilty by about 2.5 fold. Another, Effects of grapefruit juice on the pharmacokinetics of pitavastatin and atorvastatin.Br J Clin Pharmacol. 2005 Nov;60(5):494-7 Ando H, et.al, found that grapefruit juice increased the mean AUC(0-24) of atorvastatin acid by 83% (95% CI 23-144%). The problem is that such studies do not predict the magnitude of the effect in any given person. So that even were someone able to keep their daily grapefruit juice intake constant, they would need individual testing for blood levels of atorvastatin and its metabolites to determine its effect. That's just not practical, and it's much easier just to avoid the grapefruit. - Nunh-huh 13:22, 27 December 2006 (UTC)[reply]

See also Cytochrome P450 oxidase, the specific enzyme pathway affected.

Atlant 14:17, 27 December 2006 (UTC)[reply]

The effect is variable, as grapefruits have widely differing concentrations of the relevant bioactive compounds, and therefore not usable in a reliably predictable way. --Lambiam ^Talk 15:45, 27 December 2006 (UTC)[reply]

Nuclear war[edit]

What effects would a full-scale nuclear war have on humanity?

Obviously they'd be negative, but as for the scale of the destruction, I can't get a clear answer. I mean, take a look at pop culture:

On The Beach - All human life is completely wiped out, even though no nuclear weapons were deployed in the southern hemisphere
The Outward Urge - The northern hemisphere is reduced to a poison wasteland, the southern hemisphere survives and thrives.
Threads - Life survives even in the worst hit areas. Of course, it's not a good life.
Jericho - You can live right in the heartland of America and everything will be fine! :)

Which is the closest to the truth? Battle Ape 13:57, 27 December 2006 (UTC)[reply]

Most scientists don't think nuclear winter would occur, but that isn't much of a consolation. Aside from having most large population centers destroyed, the nuclear fallout would deposit lots of very nasty radioactive poisons over most of the rest of the world as well, as well as raise the level of background radiation considerably. Could humanity survive? Maybe, but it would be a very different sort of survival than we have now. Would civilization survive? Probably not as we know it. Oy. In any case we have an article on nuclear warfare which might be helpful. Of the above choices, I'd go with Threads. --24.147.86.187 14:14, 27 December 2006 (UTC)[reply]

One effect that is often under-considered (at least in popular media) is the effect on the world's economic systems. The 9/11 attacks, an attack which was relatively small-scale as war-making goes, had a vastly-disproportionate effect on morale in America (and to a lesser extent), worldwide and this propagated into substantial downturns in the US and global economies. You can bet that after a full-scale nuclear exchange, there just aren't going to be that many people buying (or manufacturing) large-screen plasma TVs; we'll be lucky if the world doesn't starve to death from lack of global trade in food. Also not inconsiderable will be the fact that a full-scale exchange will remove many of the cities that are home to the world's financial systems. It's a sure bet that the aftermath won't be pretty, and Dr. Steven Falken's strategy (of living quite near a primary target site) may well look to have been quite appealling in retrospect.

Atlant 14:27, 27 December 2006 (UTC)[reply]

Not just starve to death, but all of those bodies left to rot because there are not enough people around to bury them, or even care to do so, will be cess pools of disease just waiting for the next unwary traveller who passes by (or, who, starving, decides to eat the dead, or dying, corpse). User:Zoe|(talk) 17:54, 27 December 2006 (UTC)[reply]

Most of the population is in the cities, and those would be the prime targets. Thus most of the people would be eliminated, which is lot's fewer mouths to feed. So starvation? Who knows, certianly an overload of canned food would be available, and the can would protect the food inside from fallout. Would there be too many people left to live off the land after the radiation subsided? Who knows, and it depends a lot on the type of nuclear war, how many 'salted' nuclear weapons would be used? etc. 12.10.127.58 22:36, 27 December 2006 (UTC)[reply]

Most of the population is in the cities...

Citation for that? Although I suppose it depends on what you define as a city elligible of being on the receiving end of a nuke or ten.

Atlant 22:48, 27 December 2006 (UTC)[reply]

According to the World Almanac, using US 2000 census data, 226 million (80.3%) lived in metropolitan areas. About 135 million lived in the 25 largest metro areas. Cheers Geologyguy 22:57, 27 December 2006 (UTC)[reply]

Which still, unfortunately, leaves open the question "in a metro area worthy of a bomb?" Remember, lots of them will be expended over-targetting military installations.

Atlant 12:39, 28 December 2006 (UTC)[reply]

The fallout map above shows the targetting of only military installations. Most major metro areas would be covered in very high levels of fallout even if they weren't targetted, and many major metro areas are the sites of military installations or have military installations right next to them. "Just" targeting the military sites doesn't really get one off the hook. --24.147.86.187 14:05, 28 December 2006 (UTC)[reply]

I'd imagine that the human race would survive, even if 'civilization' as we know it didn't. There are plenty of 'crazy survivalist'-type people who prepare for the eventuality of nuclear war on a daily basis - perhaps one day they'll be the ones smiling as they emerge from their purpose-built, isolated, well-supplied underground shelters after a few months waiting for the radiation levels to decrease somewhat. The world afterwards will not be pretty - those that survived the war and the radiation will probably have to live through decades of doing their best just to survive and keeping their heads down whilst various factions fight amongst themselves for control of what's left. With no power structures left in place (how long do you reckon that the politicians that were responsible for the war would survive before being lynched once they came up for air?), there'll be plenty waiting to fill the vacuum, be it 'to rebuild the earth' or simply for their own ends. Imagine a world where anyone with leadership qualities and a political opinion gets to voice it with an army of gun-toting followers behind - a complete and utter free-for-all. --Kurt Shaped Box 01:51, 28 December 2006 (UTC)[reply]

Thanks for the answers (that map is odd though; that's one big-ass nuke that landed in Montana), but I'm specifically wondering about other countries. Obviously the USA would be a ruin, along with Russia or China or whoever started it, and probably Europe. What about lesser countries, say, Australia or New Zealand or Chile? There would obviously be economic collapse, but would they be free of fallout? Battle Ape 01:47, 28 December 2006 (UTC)[reply]

It's not one big nuke in Montana, it is an attack against the Minuteman missile fields which are/were in Montana. The map dates from the late 1980s so many of the sites have probably been decommissioned by now, though. As for countries in the Southern hemisphere — they would probably not suffer much direct fallout, though the effects on worldwide background radiation levels from a full nuclear attack would raise considerably, and it would definitely show up in their food supply over time. I'm not sure what the long-term effects of that would be but you can imagine quite plausibly a much increased level of many cancers, for example. --24.147.86.187 14:05, 28 December 2006 (UTC)[reply]

Beyond the four stories you cited at the beginning ofthis thread, you might want to see List of apocalyptic and post-apocalyptic fiction -- there are lot's of "after the next war" stories listed there.

Atlant 12:42, 28 December 2006 (UTC)[reply]

Ditto at nuclear weapons in popular culture. --24.147.86.187 14:05, 28 December 2006 (UTC)[reply]

For a pretty good example of how people manage to survive an apocalypse, may I recommend Dies the Fire by S. M. Stirling? User:Zoe|(talk) 22:15, 28 December 2006 (UTC)[reply]

Related question: What the heck is in the back end of Nebraska? 68.39.174.238 05:45, 2 January 2006 (UTC)[reply]

Many megatons of nuclear destruction, just waiting in their ICBM silos.

Atlant 17:13, 2 January 2006 (UTC)[reply]

I'm sure the human species would not be wiped out. Even a nuclear winter would be almost certain to leave some survivors (probably in the high Arctic where the ecosystem has adapted to months of constant darkness, the southern tropical rainforests [the forest floor and understory zones receive very little light], and any prepared shelters.). If there were no nuclear winter, I doubt if people in, say, Uruguay or Papua New Guinea would know anything had changed, except through the media. (There's a Ray Bradbury story about this, where a Mexican farmer watches US people flee south to avoid the final war, then shrugs and goes back to his work - it won't affect him.)

The human race has survived disasters as bad as a nuclear war would be likely to be, when we had much fewer people and resources and much less information. There was an eruption at Lake Toba during the Paleolithic which had, accroding to our article, the energy of a gigaton of TNT. That's 1,000 megatons (for comparison, Little Boy was about 15 kilotons, and the largest hydrogen bomb ever exploded was 51 megatons). Though there was no fallout, it may have caused global cooling and a nuclear-winter-type effect. Vultur

Highly unlikely that all humans would be killed.

Much much much more unlikely that all life could be wiped out. Bacteria can survive for thousands of years buried miles under ground or ice, next to boiling water, etc. If the moon collided into the Earth? Maybe, but I doubt it even then. — Omegatron 22:10, 3 January 2006 (UTC)[reply]

Tracking of dynamically-changing objects on TV[edit]

I am searching for an algorithm (or an approach) which could help track identified (outlined) objects seen on TV set. Say, if I capture a TV broadcast to a medium (tape, hard disk of a computer, etc.), is there a solution to help identify (maybe outline) an object on the screen, and then have it "automatically" tracked?

An object on TV (raster or bit-mapped) typically has the following characteristics: Its shape changes. IT appears multiple times (imagine a ball passing behind a player momentarily in a sports broadcast). Its trajectory changes. Depending on lighting and reflections, its color is not consistent, etc. Any suggestion is welcomed: An approach, a particular field of study, one or more algorithms dealing with raster-based or bit-mapped graphics.

Where should I start? Where should I research for an answer?

If you cannot think of a specific answer, is there a particular area of research or commerce I should focus on?

Thank you. I look forward to your creative suggestions and guidance!

Kelar12 14:42, 27 December 2006 (UTC) KT[reply]

The article on video tracking may be of help. - Dammit 14:55, 27 December 2006 (UTC)[reply]

Try edge detection. That's on what most of the visual tracking algorithms are based. --V. Szabolcs 22:59, 27 December 2006 (UTC)[reply]

Once you detect the object in two frames, you can calculate approximate velocity and predict which other locations to look for the object in other frames. As the object may be accelerating or decelerating, this velocity calc should be refined for each additional sighting of the object (adding a new "data point" to the displacement curve). Sightings which fall well outside of the expected location should be ignored, such as if a second, identical ball appears on the screen. This method would also allow you to plot the probably location when the object is hidden. StuRat 01:48, 28 December 2006 (UTC)[reply]

Thank you. I appreciate the feedback. Keep any new suggestions coming! Kelar12 06:39, 28 December 2006 (UTC)[reply]

2D cross-correlation of pixel values of subsequent frames? [1]

Match moving is pretty related. — Omegatron 22:00, 2 January 2006 (UTC)[reply]

Note that the apparent size may also change, as the object moves closer or farther from the camera, and the shape may "morph", as it rotates. StuRat 20:13, 28 December 2006 (UTC)[reply]

This probably won't help you if you don't have access to the broadcasts, but cricket television coverage in Australia has a feature which will show the supposed trajectory of a bowled cricket ball if it wasn't blocked by a bat or leg - used in controversial lbw decisions. This is a lot simpler than tracking the ball after it was hit (for example) or other sports like football or tennis where the ball could go in any direction. If you aren't in a cricketing nation, then check your local cable TV or web stream to see what I mean. (Looking on youtube now, but can't find anything!) -- Chuq 10:59, 30 December 2006 (UTC)[reply]

Fatty Acid Enzymes[edit]

How do the desaturase and elongase enzymes that operate on fatty acids know which types of fats to act upon? For example, why do enzymes like delta-6-desaturase "know" to operate primarily on EFAs, and not saturated or monounsaturated fats? Frankg 15:02, 27 December 2006 (UTC)[reply]

Enzymes have active sites that are very specific for their substrates and can distinguish between the different structures of the fats. David D. (Talk) 17:36, 27 December 2006 (UTC)[reply]

What was a man able to withstand of wounds and injuries during the past (medieval times) - PART 2[edit]

Moved to combine with original section above. Anchoress 21:05, 27 December 2006 (UTC)[reply]

Trans fat question[edit]

Many food labels claim a food product has 0% trans fat, but if the first ingredient in the product is partially hydrogenated oil, how can this be so? Can the trans fat be separated out and removed? Arilcv 20:35, 27 December 2006 (UTC)[reply]

The regulations in the United States, for example, allow less than 0.5g of trans fat per serving to be labelled as 0g. There are oil factionation methods that would probably allow the trans fat to be removed, but they may be more expensive than just using a different kind of oil (i.e. one that isn't hydrogenated). If partially hydrogenated oil is in the ingredients list, the product contains trans fat. Frankg 20:52, 27 December 2006 (UTC)[reply]

That loophole really irritates me. Half a gram of trans fat is not necessarily trivial, especially when the serving size is like two crackers and realistically I'm going to eat a few dozen. The upshot is that "0 g trans fat" is next to meaningless, and all the good products (i.e. Smucker's Natural peanut butter) say something like "no hydrogenated oil" anyway. —Keenan Pepper 00:23, 28 December 2006 (UTC)[reply]

I agree, this allowing companies to round down to the nearest gram is unacceptable. However, as some trans fats do occur naturally, it may be impossible to ever say a product really contains no trans fats. Perhaps what we need is an additional decimal point. Then, they could still round down, but only if the product contained less than 0.05 gram, not 0.5 gram. They will just have to decrease the serving size to a fifth of a cracker to fool us, LOL. StuRat 01:39, 28 December 2006 (UTC)[reply]

Interesting. But I bet they wouldn't sell well if they rounded up. --Proficient 12:49, 28 December 2006 (UTC)[reply]

instrument for measuring an orifice diameter[edit]

What instrument can you use to measure a very small orifice diameter?

How small are we talking?

If very small maybe a travelling microscope might do the job.--Light current 21:19, 27 December 2006 (UTC)[reply]

I was hoping to get a more quantitative measurement, to the tenth decimal. How would I use a microscope to do this?

A very fine vernier caliper might be better. -GTBacchus^(talk) 21:25, 27 December 2006 (UTC)[reply]

[2]--Light current 21:29, 27 December 2006 (UTC)[reply]

Umm - "tenth decimal" - you want to measure the diameter with a precision of 10^-10 metres i.e. 100 picometres or better ? That's the same order of magnitude as atomic bond lengths. I'm not sure that degree of precision is either realistic or meaningful. Gandalf61 22:33, 27 December 2006 (UTC)[reply]

Choose one of:

Calibrated wires of various sizes; see which just clears the orifice
Lay the orifice on a calibrated reticle and use an ordinary microscope
An optical comparator (a specialised microscope that projects onto a large screen and is used to make precision measurements of tiny things; 'shame there's no article about these, but see [3])
A scanning electron microscope.

Atlant 22:57, 27 December 2006 (UTC)[reply]