Wikipedia:Reference desk/Archives/Science/2009 October 14

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October 14

H1N1 vulnerability after infection?

My local television news just aired an interview with a studio staffer who had recently recovered from H1N1. According to the producer, he believed that he was still vulnerable to the virus despite having just fought it off; no explanation was offered for this statement. How could this be possible? Or is the staffer simply mistaken? I couldn't find anything on our article about the virus; I can't imagine how immunity would not be conveyed by having the infection. Nyttend (talk) 03:13, 14 October 2009 (UTC)

According to our article on the influenza vaccine, each particular vaccine cocktail is only good for about a year. Since that's largely due to mutation, I'd guess similar caveats would apply to folks who'd had the actual flu (i.e. yes, you could get it again next year if you'd like). This brings up the basic problem of what is meant by "same" when it comes to something that mutates as quickly as the flu bug does. Compound that by the fact that most infections and diseases are not properly identified in a lab and you're left with the unhelpful non-answer of "If he did get it again, how would he know? Matt Deres (talk) 03:38, 14 October 2009 (UTC)

I don't think it is really mutation like that. This year's seasonal flu isn't a mutated version of last year's, it is a different strain (well, combination of strains) that has reached significant levels. Immunity to the current pandemic strain of H1N1 should offer at least partial immunity to mutated versions of it, unless you get a really rapid mutation (which is possible, but unlikely), but it won't necessarily offer immunity to other strains of flu (including other strains of H1N1 - that code refers to a whole family of influenzas). However, as you say, the current strain is just a strain of flu like any other strain of flu, without detailed lab tests there is no way to tell it apart. Unless he was actually tested there is no way to know he ever actually had the pandemic strain and even if he did he could easily catch a different strain of flu in the future. --Tango (talk) 08:42, 14 October 2009 (UTC)

If I remember rightly, the TV guy said something like "I could still get it again"; it was definitely an imprecise statement such as this. I do know that he was tested and was told that the lab confirmed that it was H1N1. Nyttend (talk) 18:07, 14 October 2009 (UTC)

Well, what it means is he could get the flu again, and he could even get H1N1 Influenza A again. But it is unlikely he will get this one strain of H1N1 flu (the 2009 Swine flu) again. Look at it this way. Influenza describes a grouping of viruses which, on the Linnaean scale, would be something like Class. Influenza A would be something like a Order and H1N1 Influenza A would be something like a Family. See, even something like "H1N1" describes a large grouping of related, but distinct, viruses. Specific strains of H1N1 would be something like at the genus or species level, and vaccines are specific to the specific strain only. In fact, the standard cocktail of vaccines given every year to combat the "seasonal flu" usually contains some vaccines against some strains of H1N1 flu, just not the one specific strain being called the "swine flu". Since that strain was only discovered this past spring, it did not have time to make it into that cocktail of vaccines, so a seperate vaccine has to be initiated to catch it. Had the virus been discovered a few months earlier, it likely would be part of the standard annual seasonal flu shot. --Jayron32 20:03, 14 October 2009 (UTC)

A friend of mine actually has the swine flu and she says that she has gotten sick twice. It's been over two weeks now, and she's still very sick. I saw her after a week and she looked fine, then she got really sick again. Maybe it can relapse and then return, like malaria? It's also common to catch a cold after you catch the flu, due to your weakened state. That happened to me once. So that could be another explanation. Swine flu sounds like a very bad virus. Her husband and her brother are both in the hospital right now because of the pneumonia brought on by swine flu. So, I imagine her immune system must be pretty weak right now. I'm terrified of swine flu!--Drknkn (talk) 07:45, 15 October 2009 (UTC)

It could be a relapse (don't overdo it as soon as you start to feel better!) or it could be really bad luck and she's gotten ill twice in a quick succession. Don't be terrified - it really is just the flu. Unless you have an underlying medical condition the chance of you having any complications is really low. --Tango (talk) 11:07, 15 October 2009 (UTC)

Big Bang

Where did Georges Lemaître first use the phrase "a day without yesterday" ? Was it in the 1927 paper or the 1931 letter to Nature, or somewhere else ? Lord Labak Daas (talk) 07:42, 14 October 2009 (UTC)

I don't have access to the 1927 paper, but in the 1931 letter to Nature, which I do have, he does not use the phrase. The closest he gets is to say that "If this suggestion is correct, the beginning of the world happened a little before the beginning of space and time." --Mr.98 (talk) 14:42, 14 October 2009 (UTC)

This book about him says: He would later refer to this ultimate origin in his 1950 collection of essays The Primeval Atom as "the now without a yesterday", which has been translated as "the day without yesterday", a quote often associated with Lemaître's letter to Nature. --Sean 15:35, 14 October 2009 (UTC)

Why is the original paper on the big bang not easily accessible? Something is wrong. Weepy.Moyer (talk) 19:44, 17 October 2009 (UTC)

Antimatter fuel

Does matter/antimatter collision produce enough energy that it could be a viable power source for applications such as space travel once technology is developed to produce antimatter at a significantly lower cost? --Jean-Luc Pikachu (talk) 16:29, 14 October 2009 (UTC)

It produces enormous amounts of energy. The trick is producing antimatter using less energy than would be created - that is rather difficult. --Tango (talk) 16:37, 14 October 2009 (UTC)

See Antimatter rocket and the website How Stuff Works. —Preceding unsigned comment added by Nigelpackham (talk • contribs) 16:39, 14 October 2009 (UTC)

Antimatter utterly annihilates matter, converting all of the mass into energy. Mass-to-energy is given by $E=mc^{2}$, which yields joules if mass is given in kilograms and the speed of light is given in meters per second. The speed of light is 300,000,000 meters/second, so 500 grams of antimatter "exploded" with 500 grams of matter (1 kg total) would produce 90,000,000,000,000,000 ($9x10^{18}$) joules, approximately equivalent to a nine thousand-megaton nuclear bomb, and enough energy to run a 100-watt light bulb for almost 30 million years. In reality, a good portion of the energy would be lost to neutrinos, but yes, antimatter would make a fantastic energy source, assuming 1) we can find a way to produce it cheaply, and 2) we can find a way keep it from spontaneously destroying itself (and everything else around it for a very long distance). J.delanoy^gabs_adds 16:43, 14 October 2009 (UTC)

Since the previous posts didn't say it, I will: there is no prospect of antimatter being a viable fuel in the foreseeable future. Our antimatter article says: "According to CERN, only one part in ten billion of the energy invested in the production of antimatter particles can be subsequently retrieved." There are some schemes floating around to harvest it from cosmic ray interactions with the solar wind, but they are all extremely speculative. --Sean 16:56, 14 October 2009 (UTC)

Being a viable fuel and being a viable energy source are two different things. Obviously it's not a viable energy source since there's not really antimatter sitting around and creating it necessarily takes at least as much energy as it would release when annihilated. But as a way to efficiently store energy for vehicles where carrying around bulky fuel is an issue, it has the highest usable energy content per mass possible if the problems of creating it and storing it could be addressed. Rckrone (talk) 17:41, 14 October 2009 (UTC)

Basically, unless you can find a big pile of antimatter somewhere - AND figure out how to collect it - AND figure out how to store it without spontaneous annihilation with the walls of the container, then you aren't going to be able to use the stuff. It seems unlikely that antimatter exists anywhere in the universe in a 'natural' form...and if it does exist - it's pretty clear it won't be in our galaxy. So we fail at the first hurdle there - there isn't any of this stuff just lying around! We can make tiny amounts of the stuff - but (as others have pointed out) the amount of energy that takes is spectacular. So antimatter as either a primary fuel - or as a way to store energy is pretty much a non-starter, and is likely to remain that way for a very long time to come. However, IF you had a means to produce it with more like 100% efficiency than 0.0000000001% efficiency (which is about what we have right now) - and a way to store it (presumably in some kind of magnetic containment arrangement) - then it would certainly be the densest possible way to store energy - which (in principle) makes it useful for spaceflight - or aircraft or even cars. But we're just so very far from being able to do that - we have to say it's "impossible" until we know whatever it is that we don't already know! SteveBaker (talk) 17:49, 14 October 2009 (UTC)

An exotic application like powering interstellar flight might be one of the earlier things it could be used for, and that is not near term. Might have weapon applications as well. With respect to practical applications of antimatter, we are at the level of people experimenting with static electricity in the 1700's and speculating about electricity's possible use to run motors, for fast communication, or for lighting. Theoretically possible but not even close to practical. Edison (talk) 19:06, 14 October 2009 (UTC)

That's not entirely true. The 'P' in PET scan stands for positron, a form of anti-matter. Dauto (talk) 19:40, 14 October 2009 (UTC)

In a PET scan, we are not technically creating antimatter. We are letting an element undergo beta decay. J.delanoy^gabs_adds 21:00, 14 October 2009 (UTC)

The element undergoing beta decay is not found in nature. I is a man made element in a particle accelerator. Dauto (talk) 00:53, 15 October 2009 (UTC)

Which bit of Steve's post does that contradict? A few positrons is a tiny bit of antimatter and we use a large amount of energy (in the particle accelerators you mention) to make it (indirectly). --Tango (talk) 12:35, 15 October 2009 (UTC)

If a massive space based solar power station was created to power a space based anti-matter production machine, then once enough anti-matter had been produced (even if it took a thousand years) this matter could be taken back to earth for power production. It might be an alternative to beaming solar power down to earth using microwaves, or space elevators, which might not be practical.Trevor Loughlin (talk) 12:58, 16 October 2009 (UTC)

But you still have to solve the containment issue - that's decidedly non-trivial for any significant quantity of the stuff - remember, you can't allow your antimatter to come into contact with ANY normal matter. But in any case - with our best efforts at turning electricity into Antimatter having an efficiency of 0.0000000001% - you'd be better off leaving your space-based solar power station on the ground and connected to the power grid directly! The amount of energy you'd lose due to atmospheric absorption, poor orientation of the collector to the sun, clouds and nighttime would still be irrelevent compared to the horrific inefficiencies of turning electricity into antimatter. SteveBaker (talk) 13:33, 16 October 2009 (UTC)

ko kaaf

I want to know a little about the "Kohkaaf". given the name of the place/home land of Ghost(jin). Please tell me its answer. Thanks Mohsan saleem —Preceding unsigned comment added by Mohsan saleem143 (talk • contribs) 18:00, 14 October 2009 (UTC)

The name is usually transliterated as Koh-e-Qaf (Persian: کوہ قاف), which refers to the Caucasus mountains. See Paristan. Red Act (talk) 18:18, 14 October 2009 (UTC)

Global warming vs. record lows/snowfall

I am getting tired of my friends telling me that because their town in Saskatchewan just had a record snowfall, ipso facto global warming is made up. Is there a response for this specific kind of reasoning? Gohome00 (talk) 19:39, 14 October 2009 (UTC)

Global warming is a climatic effect, not a weather effect. See climate and weather for some differences. The big deal is that climate is the average atmoshperhic conditions over a long period of time. Weather is what is happening in one specific place at one specific point in time. Weather says "It's raining now". Climate says "It rains here a lot". The deal is, global warming says that, on average, the earth is warming up. On a local level, in specific places, on specific days, you can still have cold weather. Global warming does not mean that it will never be cold ever again anywhere. It does mean that there will be less cold days in any given period of time (measurable probably over a year or a decade); and that those "cold" days are a few degrees warmer than cold days used to be. The deal is, that things like polar ice caps grow and shrink very slowly, on the order of decades or centuries, so they will respond to conditions on the scale of decades or centuries, which is why we care about climate rather than weather. So, just because it snows in Saskatchewan today doesn't mean that global warming isn't happening. What you would need to look at is the average temperatures in Saskatchewan over a long period of time, and see what the general trend is; in the case of climate a moving average is probably the best way to judge this. --Jayron32 19:50, 14 October 2009 (UTC)

You can also direct them to the Climate Normals compiled by the Meteorological Service of Canada. They might be interested in looking at local trends over the span of decades, rather than specific days, years, or weather events. Note the important difference between local and global climate, also. I would also like to point out global climate change as opposed to global warming - which are related but distinct phenomena. Nimur (talk) 19:59, 14 October 2009 (UTC)

Riding on what Nimur said, in my neck of the woods (Central NC), a lot of people are rejecting the Global Warming phenomenon and discussing instead Global Climate Change. Global Warming makes it sound like the entire globe is going to heat up. On average, it will, but while it may get hotter in country X, it may get to be a mini-ice age in country Y. Also, Global Warming doesn't begin to cover the ideas of droughts and floods, which are also cited as being major factors associated with this event. Falconus^{p t c} 22:13, 14 October 2009 (UTC)

Am I alone in reading Opie's question as How do you argue against an arguer taking statistically insignificant facts and using them as evidence?"...He asked about this specific kind of reasonining, not this argument. 90.208.3.84 (talk) 23:14, 14 October 2009 (UTC)

A response to the OP's tiresome friends is to invite them to read the article Statistical significance. Cuddlyable3 (talk) 15:13, 15 October 2009 (UTC)

Ah, good point. I would say that the argument that I would use is that 1) it is an average trend over time, not that tomorrow is automatically going to be warmer today, and that 2) Global warming is somewhat of a misnomer as it will warm some places and cool others. The overall general trend however is to get warmer.

Yes - the response is that changing and unusual weather are precisely what proves that there is something weird going on. As we discussed a few days ago, Texas has gone through one of the most prolonged hot periods on record - and is now getting the highest rainfall on record. The key things here are that:

• The "weather" (what's happening here and now at whatever specific place you are at) is getting crazier - sometimes crazy hot, sometimes crazy cold, sometimes crazy windy, othertimes crazy rainy - or droughty. Records are being broken at a much higher rate than in the past - which is quite contrary to expectations - which is that the longer we keep records, the lower the probability that they will be broken.
• The "climate" (what's happening on average over a few years over the entire globe) is getting hotter.

As the climate warms up - the weather will get crazier. Sure, on the average that weather will be warmer than usual - but it's very possible for climatic warming to cause cool weather locally. An unusually cold spell in Saskatchewan is more than balanced by an even more unreasonably hot summer in Texas.

SteveBaker (talk) 00:31, 15 October 2009 (UTC)

good point. not only is the mean temp rising, but the standard deviation is rising as well, meaning an increase in the frequency of record lows as well as an increase in the frequency of record highs (but more of the latter). also more record wind velocities, precipitations, dry spells, etc. what you'd expect if more energy is being entered into the system, but it isn't being entered uniformly over space and time. Gzuckier (talk) 20:27, 18 October 2009 (UTC)

Plate movement rvsals

Removed question from sock of banned User:FreewayGuy. Please take any debate to the discussion page. SteveBaker (talk) 23:41, 14 October 2009 (UTC)

Oops! No wonder I never got complete answer. They even mention it on Pangaea Ultima artilce which I never bother to study it. And North American is attach with Eurasian plate. See the green and the brown boundarys and Pacific Plate is yellow. Theose tools have answer my questions. Those questions is probably sound alot like homework questions to normal peoples.--209.129.85.4 (talk) 19:01, 15 October 2009 (UTC)

average size of a penis

laugh all you want, because i am too right now. but i want to know, whats the average size of a mans penis age 18-25? i know im going to be laughing about this one all day --Talk Shugoːː 20:49, 14 October 2009 (UTC)

The NSFW article Human penis size will tell you all you want to know. And more. Just makes sure the kids have gone to bed and/or your boss is not lurking around your cubical. --Jayron32 20:54, 14 October 2009 (UTC)

Well i am at work so I won't be clicking the link. It is probably discussed there, but I find it a really amusing anecdote how there was an old study, IIRC from the 60s or 70s that asked men to measure them selves and record the result. That results of that study were used for decades as the basis for "average" penis size. What they neglected to factor in is that most men when measuring them selves were, lets say, generous with their result, pretty much systematically adding half to a whole inch to the actual result. This probably accounted for a whole generation of "average" men suffering penis envy because they thought they were really an inch below average. A more recent study in which men were measured by nurses revealed a more accurate, and not surprisingly lower figure. Vespine (talk) 23:42, 14 October 2009 (UTC)

About that last sentence you wrote there... Did they get a figure that was lower than the original figures and this was not surprising, or did they get figures that were not far enough below the original figures to surprise anyone? APL (talk) 02:42, 15 October 2009 (UTC)

Sorry probably needs a comma after "surprisingly", as in it didn't surprise anyone that the figure was lower, especially after they realised the error in the method used for the first study. Vespine (talk) 03:14, 15 October 2009 (UTC)

You need two commas: "and, not surprisingly, lower". --Tango (talk) 08:50, 15 October 2009 (UTC)

I'm surprised it wasn't a bit bigger if it was measured by nurses. Interesting to read how they managed that. :) Dmcq (talk) 11:53, 15 October 2009 (UTC)

These days I believe they administer Viagra (or similar) to ensure consistency in that respect. --Tango (talk) 12:57, 15 October 2009 (UTC)

but what if thay didnt have viagra then lol? kinda would make you wander. and thanks jayron for the link, luckly i dont have kids yet but i am at work. --Talk Shugoːː 17:27, 15 October 2009 (UTC)

I think some poeple might be falling for the stereotype, a Nurse in no way implies they were female. And so what if they didn't have viagra? A sperm bank manages just fine without viagra, and there would already be nurses on hand, wouldn't there? "While you're doing that do you mind if we measure your jhonny?" I don't think that's the way they did it since that would also introduce a bias, under average people might be less likely to agree, but i'm just using it as an example why i think "not having viagra" isn't an issue. Vespine (talk) 23:02, 15 October 2009 (UTC)

To be honest, there were so many music hall assumptions in Dmcq's answer that it's about a century out of date with reality. Simpler just to move along than try to unpick it. 86.140.149.215 (talk) 23:16, 20 October 2009 (UTC)

Which parts of the USA have a climate similar to London?

Particularly in terms of the summer and winter temperatures. Many parts of the US have I think extremely hot summers and extremely cold winters compared with those in London. Thanks. 92.29.126.121 (talk) 21:40, 14 October 2009 (UTC)

No part is quite the same, but the Pacific Northwest is most similar -- the area around Seattle. Looie496 (talk) 21:44, 14 October 2009 (UTC)

Given that England is surrounded on all sides by water, it's climate tends to be a lot more moderated. Most of the islands in the US (Alaskan islands aside, for which I do not know the weather patterns) are rather far south, so their climates tend to be far warmer on average. Since none of the continental US is a small island in the North Atlantic, the weather patterns will tend to be more varied and more extreme. Falconus^{p t c} 22:18, 14 October 2009 (UTC)

"Most of the islands in the US...are rather far south" I wonder which islands you had in mind and am not sure the "most" part is correct. Certainly we have a number of islands here in the Great Lakes rather far north and the Seattle area has several as well. 75.41.110.200 (talk) 15:05, 16 October 2009 (UTC)

I agree with Looie, the Pacific NorthWest is pretty similar. TastyCakes (talk) 22:23, 14 October 2009 (UTC)

I'm in Vancouver here and although the general regime is comparable, the 'type' of precipitation, the type of sunny day, the type of frigid air mass, is rather dissimilar. Vranak (talk) 14:03, 15 October 2009 (UTC)

In what way are these things different from London please? And, another item, I've always been suprised that somewhere as far north as Vancouver (and not maritime) could have a nice climate. 78.151.108.233 (talk) 11:46, 18 October 2009 (UTC)

Vancouver is actually closer to the equator than London. Being near an ocean moderates climate - London, where it never, ever, ever gets really cold, is further north than Winnipeg, where actual real authentic cold occurs. This is in part because London is close to the ocean. --NellieBly (talk) 12:03, 18 October 2009 (UTC)

In London it you usually get some snow on two or three days a year. Does not that count as cold? 78.151.114.229 (talk) 09:58, 19 October 2009 (UTC)

The US is farther south, but London (and most of western Europe) gets heated by ocean currents flowing from the tropics. That's why Ireland is considered to have a temperate climate, while southern Labrador, at a similar latitude, is considered subarctic. --Carnildo (talk) 23:19, 14 October 2009 (UTC)

Agreeing with all of the above, at London, you will find a link taking you to Oceanic climate. The map, will show the NW as in the same range as London, with Portland and Seattle listed alongside London in the Notable Cites of Oceanic Climate. --Preceding unsigned comment 02:39, 15 October 2009 (UTC)

On a pedantic note, England is not surrounded on all sides by water (see above). It has two land borders: Wales to the west, and Scotland to the north. If you're visiting, then it's good to not upset the natives. Bazza (talk) 14:28, 15 October 2009 (UTC)

That's actually quite relevant to the question, as Wales and Scotland, being mountainous areas and bordering a large expanse of water, suffer much higher rainfall and lower temperatures than London does. London is in the East Anglian rain shadow, and has a climate more comparable to Brussels or Paris than to Cardiff or Edinburgh. OR it's a good layer of clothing warmer than Wales or Scotland. --TammyMoet (talk) 15:17, 15 October 2009 (UTC)