Wikipedia:Reference desk/Archives/Science/2008 September 9

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September 9

HIV taxonomy

To which kingdom does it belong? I have been able to find the genus and family but not the kingdom. Not even on Virus Taxonomy Online or the ICTVdb Index of Viruses

Thanks in advance!

Sorry for signing with an IP200.63.228.51 (talk) 01:19, 9 September 2008 (UTC)

Viruses aren't classified in Kingdoms. Which is why you can't find one! - Nunh-huh 03:56, 9 September 2008 (UTC)

So, I get the 'how' but not the 'why'. What's the issue with designating a separate virus kingdom? --Kurt Shaped Box (talk) 06:21, 9 September 2008 (UTC)

(edit conflict)The ICTV system starts at Order and goes down from there. See Virus_classification#ICTV_classification.--Scray (talk) 04:00, 9 September 2008 (UTC)

A lot of biologists would dispute that viruses are even life-forms. It's a thin line between complicated chemical agents and actual life. SteveBaker (talk) 04:45, 9 September 2008 (UTC)

Does anyone who's anyone still believe that prions are alive? I know that there was a bit of debate about that a few years ago, when Mad Cow was in the news. --Kurt Shaped Box (talk) 06:16, 9 September 2008 (UTC)

Wikipedia has an article on this: Virus classification. Also see Kingdom (biology) for the way things have changed over time in the taxonomy of living things. -Arch dude (talk) 12:49, 9 September 2008 (UTC)

From that article and others, we can see that there is no scientific consensus on a taxonomy with a single root, so there is no virus "kingdom." For the other kingdoms, it is reasonable to assume that each kingdom arose from a common ancestor and that the kingdom divided by evolution and natrual selection into finer and finer divisions, each with a common ancestor (approximately.) This is not likely for viruses. Viruses are likely to have arisen multiple times in multiple hosts. Therefore unless a bunch of viruses appear to be similar enough to suggest evolution from a common ancestor, scientists are unwilling to assign them to the same grouping. -Arch dude (talk) 14:07, 9 September 2008 (UTC)

Check this out?

I know it seems ridiculous, but could someone with some scientific background look into this? It appears to be unlikely, but I'm just wondering, does it have any scientific truth?

Official Site Ebay Page PerfectProposal 01:00, 9 September 2008 (UTC)

Only truth that springs to mind starts "A fool and his money...." Arakunem^Talk 01:09, 9 September 2008 (UTC)

What is there to say about it? He never really says how he did it, or what evidence there is it works. He's just asking you to blindly hand over 25M...Someguy1221 (talk) 01:19, 9 September 2008 (UTC)

Just tell him he has to pick it up last Tuesday. Dragons flight (talk) 02:41, 9 September 2008 (UTC)

Now there's a potential scam, ripe for the exploiting. Tell the mark that you're collecting payment in cash, as arranged, for time-travel related services rendered in the future and that all will be made clear if they go check the eBay auction/website on <date in future> and make contact... --Kurt Shaped Box (talk) 06:14, 9 September 2008 (UTC)

Oooh! That's good! You wear a shiney silver costume and knock on people's doors: "Hello! I'm a time traveller from 20 years into your future. The future-you told me to come back in time and tell you to invest $10,000 in this company so that when the stock price skyrockets next week you/he will become a multi-billionaire." ...very good! SteveBaker (talk) 15:12, 9 September 2008 (UTC)

I wonder why time travel is so expensive. He doesn't even mention needing any equipment. APL (talk) 02:17, 9 September 2008 (UTC)

Beware of Those who Capitalize Lots and Lots of Words. Besides, if it worked, this person could have gone back in time, invested in the stock market (selling Fannie Mae and Freddie Mac short comes to mind) and cleaned up. Clarityfiend (talk) 02:48, 9 September 2008 (UTC)

Wow! That's a pretty bold con trick! I like the way that there is ZERO information on any of the pages. I've filed a fraudulant sales report with eBay.

He's given himself "3 to 5 years" to spend the cash and find someplace to hide from his investors. If it really worked, his future self would already have gone back in time and told himself which horses to bet on to get the cash to develop it...and probably given himself the plans and the dilithium crystals to make the work take less time. I guess that's how we know it's not real.

SteveBaker (talk) 04:43, 9 September 2008 (UTC)

Ahh, A a little GF wouldya? The guy might just be your common-or-garden internet nutcase - or just another attention/lulz-seeking hoaxer. ;) Seriously though, if that auction stays open, it will attract bids from people with no intention of paying (that's not intended as an incitement to do that, seriously, guys!) - these things always do. I don't know offhand what the Final Value Fee on $25million will be - but it won't be small... --Kurt Shaped Box (talk) 06:10, 9 September 2008 (UTC)

WP:AGF is a Wikipedia rule - it doesn't apply in real life. When someone is so clearly attempting to scam some gullible investor out of millions of dollars - I regard it as my responsibility as a rational human being to do something about it. In this case he's clearly breaking eBay's bylaws - so I reported him. If he breaks Wikipedia guidelines, I'll report him for that too. There aren't many rules on the Internet - but where there are, let's try to enforce them. SteveBaker (talk) 06:29, 9 September 2008 (UTC)

Didya not see the smiley, Steve? I wasn't being strictly serious... :) --Kurt Shaped Box (talk) 06:33, 9 September 2008 (UTC)

Oh come on, be fair!! He clearly does say how it works - dimensional tunneling, whatever that is. I am a little puzzled why he does not just send a completed machine back in time though. It would avoid all those tedious development costs. SpinningSpark 15:54, 9 September 2008 (UTC)

You cynics. I will have had a lovely meal at Milliways, or just got back from will having had one. --- OtherDave (talk) 21:47, 9 September 2008 (UTC)

I wonder what sort of fee eBay must have charged him for a $25,000,000 auction price. ~Amatulić (talk) 00:06, 13 September 2008 (UTC)

I have a question about Reno, Nevada

My daughter is doing a school report and needs to find out Reno's proximetry to the ocean. (removed e-mail address to protect from spambots) 75.15.211.224 (talk) 03:28, 9 September 2008 (UTC)Brandi

We aren't supposed to do people's homework - but I would suggest going to Google Maps - enter "Reno, Nevada" then back out until you see some ocean. Pick a city on the coast and ask Google to plan a route from Reno to that city. That would be the driving distance - the "as the crow flies" distance will be a bit shorter. SteveBaker (talk) 04:33, 9 September 2008 (UTC)

And to find the crow's distance easy, if you have Google Earth, you can click on the ruler button to drag a line between two points, and the program will tell you the distance you've just drawn across. Someguy1221 (talk) 05:02, 9 September 2008 (UTC)

(When you look at the map - it's pretty clear what the nearest city is (hint: it has a really pretty orange bridge) - and that driving route is pretty direct...in this case). SteveBaker (talk) 05:28, 9 September 2008 (UTC)

Or use this excellent tool. Bazza (talk) 13:02, 9 September 2008 (UTC)

You'll get extra points for originality if you don't choose the same boring ocean as everyone else. Try the Arctic or Indian. --- OtherDave (talk) 21:50, 9 September 2008 (UTC)

In this education system? I think even a distance to the Atlantic will get you marked down. --antilived^{T | C | G} 00:15, 10 September 2008 (UTC)

Birds with Blue Eyes

Are there any birds (especially raptors) that have blue eyes as their population's predominant phenotype? 76.121.209.96 (talk) 05:18, 9 September 2008 (UTC)

The Blue-eyed Cockatoo, as the name implies, has blue eyes. Not a bird of prey, though. Fribbler (talk) 16:19, 9 September 2008 (UTC)

Jackdaws have particularly striking, steely-blue eyes. Not a bird of prey either though... --Kurt Shaped Box (talk) 18:57, 9 September 2008 (UTC)

Harpy eagles seem to fit the criteria. Matt Deres (talk) 19:54, 9 September 2008 (UTC)

And heres an article on the Philippine Eagle that may also fit the bill. Fribbler (talk) 22:24, 9 September 2008 (UTC)

Diet of the Canada Goose

Do Canada Geese ever eat fish? 71.113.3.76 (talk) 07:30, 9 September 2008 (UTC)

Yes, according to this. Go to the section on "diet". Zain Ebrahim (talk) 08:09, 9 September 2008 (UTC)

slip of tongue

How and why people have slip of tongue? —Preceding unsigned comment added by Adityamendel (talk • contribs) 10:51, 9 September 2008 (UTC)

I think it's generally caused by being distracted while speaking, you're thinking one thing and saying another and you end up saying something else (often related to what you were thinking). You may like to read Freudian slip. --Tango (talk) 10:59, 9 September 2008 (UTC)

Check my chemistry questions

I have the following questions and the answers Ive gotten are below each one. Tell me if they are correct:

1. Write the full equation for sodium reacting with bromine to form sodium bromide
   • Na₂ + Br₂ -> 2NaBr
2. Write the half equations for the same reaction
   • Na₂ -> 2Na⁺ + 2e^- and Br₂ + 2e^- -> 2Br^-
3. State which species is being oxidised and which is being reduced
   • Br₂ is oxidised. Na₂ is reduced.
4. State which is the oxidant and which is the reductant
   • Na₂ is the oxidant. Br₂ is the reductant

I think its pretty much right but one thing Im definitely not sure of is this: in questions 3 and 4 should my answers read, for example, as I said "Br₂ is oxidised" or "2Br^- is oxidised"
Thanks --RMFan1 (talk) 12:26, 9 September 2008 (UTC)

You're on the right track as far as balance. Check the redox page for definitions of the various terms and roles of the reductant and oxidant. Regarding notation, something written as X_y means a single molecule (or polyatomic ion) consisting of y atoms of element X together. Writing yX means a collection of y distinct X atoms or polyatomic ions. So you have to figure out whether there is such thing as, for example, an actual molecule composed of two bromine atoms or whether bromine exists as single atoms (and therefore you'd just have two of them). You can read our bromine and sodium pages to see what their stable forms are. DMacks (talk) 14:32, 9 September 2008 (UTC)

Is it me or are the reduction and oxidation the wrong way round?59.100.192.85 (talk) 23:28, 9 September 2008 (UTC)

Redox has the defs:) I usually try to think about it in terms of the charge on each atom and whether it's going down (being "reduced") or whether at atom is doing something to cause another atom's charge to go down ("reducing" it). DMacks (talk) 01:25, 10 September 2008 (UTC)

Helpful mnemonic is OILRIG: Oxidation Is Loss (of electrons); Reduction Is Gain. Gandalf61 (talk) 13:12, 10 September 2008 (UTC)

There are two major mistakes in your homework. However the Wikipedia reference desk is not supposed to be for your homework questions. Axl ¤ [Talk] 20:12, 11 September 2008 (UTC)

alien

could the alien exist in real life, could it be a serious threat if it came out to earth, and could we kill it or would they win? Bradley10 (talk) 13:03, 9 September 2008 (UTC)

If memory serves, the alien in Alien wasn't capable of space travel, it only became a threat because the humans on the film went to its planet. I very much doubt an alien like that can exist anywhere in this solar system (except possibly Earth, but then it wouldn't be an alien!), so until we invent interstellar travel we should be fine. After that, it's anybody's guess! --Tango (talk) 13:22, 9 September 2008 (UTC)

Soylent green

The real Soylent green? —Preceding unsigned comment added by 71.100.10.144 (talk) 14:11, 9 September 2008 (UTC)

It's a kind of CO2 sequestration technique - except that it's really not going to work long term.

The idea is to capture the CO2 produced by some kind of nasty coal fired power station - use sunlight to cause algea to convert that CO2 into carbohydrates - then to harvest the algea and convert the carbohydrates into methanol or something - which . However, when you use the resulting fuels - the CO2 is released into the atmosphere again...so you didn't sequester it. Someone will probably argue that when you burn these new fuels, you could use the same technique to sequester that CO2 - but now you have an infinite regress because you're continuing to pump CO2 into the "system" so more and more and more algea are needed in order to sequester it. The only answer is to NOT convert the algea into any kind of a fuel at all - but instead to dump it back underground. The trouble is that the cost of doing all of this is so high that you can't afford to just dump the results back into a hole in the ground.

If you are going to invest in a "solar to ethanol" plant - then do it without the nasty power plant generating the CO2 - let the algae take the CO2 from the air - that would be a truly "carbon neutral" solution.

So - this is another effort by the "Clean Coal" people to pursuade us that they can continue to build big, polluting coal-fired power stations without killing the planet. They just hope that by confusing the science like this that the general public will fall for it...and the annoying part is that they probably will because the problem with it is pretty subtle.

SteveBaker (talk) 14:57, 9 September 2008 (UTC)

It sounds like the idea is to take advantage of the concentrations of CO2 that you get at the source in order to grow the algae more efficiently, it's not a CO2 sequestration technique (if it's being described as one somewhere, I expect that's the press not knowing what they're talking about). --Tango (talk) 15:11, 9 September 2008 (UTC)

Yes, you are right. Although the algae could be used to permanently sequester carbon by turning it into biochar, bio-oil and syngas the idea here is much more sophisticated. Some algae species produce up to 50% of their body weight in vegetable oil, which can be extracted first and even tailored to produce compounds that lend themselves better to one form of end product than another such as jet fuel versus heating oil versus salad oil. The remaining components can then be used as a dietary supplement or as cattle feed or as feed stock for biochar, etc. —Preceding unsigned comment added by 71.100.10.144 (talk) 16:28, 9 September 2008 (UTC)

Well you're not adding to the problem you're just recycling stuff that's already been released from fossil fuels. It's not a solution but you seem to insinuate that you're making it worse when you're not you're just keeping the problem the same and making some energy at the same time right? Dereconstruct (talk) 22:15, 12 September 2008 (UTC)

If it were being sold as "This is a way to make some fuel from solar power that (incidentally) has to be co-located at some nasty fossil fuel power station - but which doesn't improve the carbon footprint of fossil fuel power stations at all." - then you'd be right. However, if it's sold as "Look! We're taking all of that nasty CO2 out of the flue gasses of a "Clean Coal" power station and turning it into ENERGY!!!" - then it's a very nasty way to trick people into believing that we can still have fossil-fuelled power stations without killing the planet - when in fact this does NOTHING to help the carbon footprint of the power plant at all! If the latter is the case (and it undoubtedly is) - then this is a nasty trick that won't help the world at all - and in fact (because it'll fool those stupid politicians with their very tiny brains), it'll do us all a great deal of harm because it'll foster the idea that we can still burn megatonnes of coal every year. SteveBaker (talk) 13:55, 14 September 2008 (UTC)

Symbols

Hi! Whics symbols (Xn, T, C, N, T+ ...) are on : - Liqui Moly (alloy for fuel) - chlorine - cyanohydrin acid ? Thank you! —Preceding unsigned comment added by Atacamadesert12 (talk • contribs) 15:54, 9 September 2008 (UTC)

You generally need a specific product name, then you can use Google to search for "xxx hazard symbols". For instance, I was able to find the safety data sheet for one Liqui Moly product: [1] and the symbols are Xn, R42, S2, S23.3, S45 and S51. You can reference the meaning of the symbols here: [2]. Franamax (talk) 00:28, 10 September 2008 (UTC)

crossbreed dogs

I'm pretty darn sure it's possible to breed two different species of dogs together, to create a mixed-breed dog. Can all species of dogs mate with all other species of dogs? Or are there cases where it doesn't work? Bradley10 (talk) 15:56, 9 September 2008 (UTC)

Well, there's only one (sub)species of dog, canis lupus familiaris. All breeds should be able to interbreed, however. — Lomn 15:58, 9 September 2008 (UTC)

i would counsel against attempting to cross a Great Dane dog with a Chihuahua bitch, however. DuncanHill (talk) 16:00, 9 September 2008 (UTC)

Duncanhill, is that sort of thing possible, if inadvisable? Is it because of the potential size of offspring, or the physical difficulties of such a coupling? Not to mention the tie? Bradley10 (talk) 16:14, 9 September 2008 (UTC)

I am not a dog breeder, but I suspect that all the things you mention would conspire to make it physically impossible, though of course, as members of the same species they would theoretically be capable of producing viable offspring. DuncanHill (talk) 17:12, 9 September 2008 (UTC)

It is possible to crossbreed all dogs (assuming the male and female you use can breed). In a professional sense, any obstacles with dog size and temperament do not matter. The sperm is collected from the male and the female is artificially inseminated. Of note, wolves can be crossbred with dogs as well, but you do not get tame wolves. You get dogs that will snap and attack anyone and anything at any time. -- kainaw™ 18:00, 9 September 2008 (UTC)

And, of course, we have an article: Wolf-dog hybrid with a section that goes to great lengths to claim that while wolf-dogs have an erratic temperament, it is not possible to know exactly how any dog will act in all situations. Way to rationalize there! -- kainaw™ 18:03, 9 September 2008 (UTC)

Medicval term for 'facial flushing'

Niacin says "People taking pharmacological doses of niacin (1.5 - 6 g per day) often experience a side-effects that can include dermatological complaints such as facial flushing and itching, dry skin, skin rashes..." (my bold). What is the medical term for facial flushing? RJFJR (talk) 16:15, 9 September 2008 (UTC)

Facial erythema. But in reality "flushing" is used just as often or more often in cases when the pathology is not the skin itself. Fribbler (talk) 16:20, 9 September 2008 (UTC)

"Plethora" and "florid" also are used.--Scray (talk) 01:08, 10 September 2008 (UTC)

Oh no, no sunspots!

There haven't been any sunspots for over a month now. Is this a bad thing? 31306D696E6E69636B6D (talk) 16:42, 9 September 2008 (UTC)

Nah, we're right smack in between Cycle 23 and 24, so things are at a minimum right now. They should begin to pick up again soon, (hopefully for my DX'ing), but its not unheard of for a minumum to stretch out for a bit (see Maunder Minimum) Arakunem^Talk 17:05, 9 September 2008 (UTC)

Yes, high solar activity improves skywave propagation because the increased radiation helps ionize the ionosphere that long-wavelength radio waves reflect off of (see http://www.blackcatsystems.com/propagation/solar_flux.html). On the other hand, solar flares are more frequent during the solar maximum and can cause propagation to vary wildly.

Arakunem: out of curiosity, how great of an effect does the solar cycle has on a DX'er? --Bowlhover (talk) 04:52, 10 September 2008 (UTC)

It has a huge effect, with high sunspot parts of the cycle propagation of much higher frequencies occurs even into the low VHF bands. The signals bounce off the inside of the ionosphere back to the earth, and then up and down of the earth again. Though if you want to receive low frequencies from Space say 1 MHz, or get a clear GPS signal, then now it the opportunity. Now all the shortwave stations have to pack themselves down the low frequency end where there is more interference and absorption, and more static. Graeme Bartlett (talk) 05:12, 10 September 2008 (UTC)

The article on the Maunder Minimum says that this occurred at the same time as the coldest part of the little ice age. That's what i'm worried about. 31306D696E6E69636B6D (talk) 13:10, 10 September 2008 (UTC)

Neutron stars

The first direct observation of a neutron star in visible light. The neutron star being RX J185635-3754.

The article neutron star states the radius of a neutron star is usually between 20-30 km. However, this image shows a visible neutron star. How is it possible for us to see objects this small so far away in space? (although that's an assumption, maybe it's not that far away) —Cyclonenim (talk · contribs · email) 17:06, 9 September 2008 (UTC)

It's not the size that matters, it's the luminosity. Stars are generally unresolved in astronomical images. Similarly, you can see the light from my flashlight from hundreds of yards away, even though the filament might be smaller than your eye's resolution. -- Coneslayer (talk) 17:10, 9 September 2008 (UTC)

Here's some perspective: the largest known star is thought to have a diameter similar to the orbit of Saturn, around 2.8 billion km. The neutron star you linked to is about 450 light years away, and you say 20-30 km diameter for a typical one of those. Let's pretend those two stars are the same distance away from Earth. So using my decrepit memory of trigonometry, I can compute:

   radius_canis   =  2800000000 * 1000
   radius_neutron = 20 * 1000
   distance = 450 * 3*10^8 * 365 * 24*60*60
   angle_in_sky_canis   = tan(radius_canis   / distance)   = 0.00000067         degrees
   angle_in_sky_neutron = tan(radius_neutron / distance)   = 0.0000000000000047 degrees
   angle_in_sky_pinhead = tan(.001           / 1000)       = 0.000001           degrees

So the angle that the neutron star takes up in the sky is indeed *much* smaller than the angle that the big star takes up, as you observed, but consider this: if there were a pinhead being held one kilometer up in the sky it would easily eclipse both stars. --Sean 20:08, 9 September 2008 (UTC)

You must understand that when you see an astronomical photograph with stars in it, the brighter ones will often look bigger, but this is not because the photo is showing their true diameter. It's because no matter how perfect the telescope is, you never get all the photons from the same distant point perfectly focused into the same spot on the film (or digital sensor). With a bright star the scattered photons are sufficient to expose the film and make a slightly larger image. As far as photography is concerned, practically any star is a point source -- only a few of the very largest stars have had their diameter directly measured. The diameters that you see given for stars as well as neutron stars are computed based on theory, not measured directly. --Anonymous, 21:58 UTC, September 9, 2008.

It's also possible (especially with a White Dwarf) that the light you see is being scattered off of dust and gas surrounding the actual object's planetary nebula. That would make it seem a lot bigger than it actually is. SteveBaker (talk) 23:45, 9 September 2008 (UTC)

In the case of a neutron star, you may be seeing light emitted in it's neighbourhood, generated in the same way as the radio pulse, by electrons accelerated by the spinning magnetic field. We need Sean to calculate what temperature the surface would have to be to get that luminosity, which looks to me to be around 10¹⁶ times hotter. Suggesting that the radiation may not be thermal. Graeme Bartlett (talk) 05:18, 10 September 2008 (UTC)

Core skills of a chemist

Lately I've realized I really have a sincere interest in chemistry. Been reading a little on my own, in my own pace. I've tried college before and it's just not for me, I simply can't stand the boring stuff that inevitably comes with an otherwise interesting topic. Still, I began to think if maybe distance studies - not sure if this concept exists in English, but essentially means studying from home, basically no classes to attend - would work for me. That way I could focus on one semester at a time, so if I felt fed up after one semester I could take a break and just work until I felt motivated again, instead of being on a forced 3-4 year course.

Aaaaanyway, that's just the background. My question is simply this: What are some of the core skills of an aspiring chemist, without which a person would experience difficulties going through an undergraduate level of chemistry education.

Thanks in advance for your answers, I'll be waiting eagerly. Jack Daw (talk) 18:00, 9 September 2008 (UTC)

I think the main problem you would face would be practical kills. It's not just enough to have the required knowledge, you also have to actually be able to perform your experiments in an actual lab. You have to know that that's just a whole different ballgame. Another problem of course is that the " boring stuff " is often required to understand the interesting stuff. Most chemists I talk to hate quantum physics and higher level mathematics with a passion, yet they agree that it's pretty much required knowledge. Just my two cents PvT (talk) 18:08, 9 September 2008 (UTC)

I'll second that. Not only is it the case that the "boring bits" are necessary to learn the skills - but also, if you were to become a practicing chemist, a large fraction of your working week would be spent on doing those very "boring bits". If you don't like the boring bits of learning - the odds are very good that you'll hate the job too. It's not common for college courses in the hard sciences to teach things that you won't need to both know - and use on a frequent basis. A similar issue comes about with your desire to take a break until re-motivated...doing that in a daily job would make you pretty unpopular really fast! SteveBaker (talk) 19:01, 9 September 2008 (UTC)

Additionally, these days, I think it is difficult to get a good job as a chemist without a degree. ike9898 (talk) 19:14, 9 September 2008 (UTC)

Hmm perhaps I was a bit unclear about what I meant about core skills. Obviously, even with distance studies I would get lab work, do the boring stuff, and get a degree, which I think were your combined points. What I meant with core skills was, if there are certain ways to think that are valuable, certain ways to look at things, e.g.; does a chemist have to be analytical, have a sense for details, able to see the big picture, be creative, have an excellent working memory, etc etc, the list could go on for very long.

Also, btw, it's been my experience that once you actually get out to work, even the boring parts become enjoyable, SteveBaker ;) ....... Jack Daw (talk) 19:26, 9 September 2008 (UTC)

That depends a lot on the individual - and (perhaps) the career. I don't know chemistry - but in my line of business (computer programming), it's necessary to document your software as well as design, code and debug it. I know an awful lot of programmers who love the programming bits - but utterly loathe doing documentation. Having to actually write lots of English prose is one of the "boring bits" for those people. So perhaps you don't happen to have any bits of your job that really were boring in the first place...that's the same with me - I'm a programmer who doesn't mind doing documentation in the least. My point is that if you think you just have to get through the boring bits so you can get your degree and they you won't have to worry about it anymore after that...then you're kidding yourself. SteveBaker (talk) 21:04, 9 September 2008 (UTC)

Aside from the traits you mentioned I would say that a good head for numbers is a big plus. Other helpful skills would include: good manual dexterity, good people skills (you rarely work alone), technical aptitude (you work with machines) and lots of motivation. Note that these aren't requirements, they're just handy traits to have PvT (talk) 20:04, 9 September 2008 (UTC)

(ec)Probably the biggest one would be to understand and appreciate the Scientific Method. You also won't get far unless you understand the Atomic Theory (things are made of atoms) and the nature of the chemical bond (atoms share electrons). Understanding the difference between a chemical change and a physical change is key too. After that, what you'll need to know varies based on the discipline, e.g. analytical chemistry versus organic chemistry versus biochemistry. Not only is the knowledge base different, it's been my experience that the scientists in each have slightly different mindsets. Back on a general note, to deal with practical issues one should be intimately familiar with SI (the metric system), as well as scientific notation, along with general concepts of measurement, including significant figures/propagation of uncertainty and the distinction between accuracy and precision. On a side note, learning a dimensional analysis system, such as the factor-label method, will likely save you lots of grief when doing calculations. -- 128.104.112.147 (talk) 20:12, 9 September 2008 (UTC)

(ec #2) Excellent list. These are all things that are pretty necessary for a bachelor's degree in general chemistry. Of course, there's always sepcialization for higher level degrees. For example, us theoretical/computational people need very good high-level math, and computer programming - but lab skills aren't terribly important. For analytical, good "lab hands" and attention to detail, along with a very good mechanical and scientific knowledge of what instruments you are using, but you won't use much math beyond basic calculus, if that (most of the instruments will do the math for you nowadays).

For me personally, visualization is important, with a healthy dose of memorization ability (but not necessarily a lot). Being able to visualize structures and reactions (in three dimensions), along with how to do things in a lab, is an incredibly helpful skill in almost all areas of chemistry. --Bennybp (talk) 20:23, 9 September 2008 (UTC)

Help identify this plant

I'm trying to identify a bush/shrub. I'll provide photos if we can't figure this out, but I'll try to describe the plant. It is a medium sized bush (the one I see is probably 4 to 5' all around) which I think is common in the southern United States. At least it can be found in central and south eastern Virginia. The leaves are roughly 3-4" big and a darker green on the top, lighter green on the belly. They have distinctive serrations on the entire edge of the leaf. They feel almost the same as a butter knife. The leaf, when turned sideways, looks almost like lips (elongated oval) that comes to a point at one end. The leaves are thick and waxy. This is also a flowering bush. They are not flowering now so I cannot give much more detail, but I believe they have golf ball sized buds that open up to rather large flowers with lots of pedals that turn brown and fall off. (I could take a picture of one of the brown, dead flowers). Any ideas? Anything else I could look for to help someone identify the plant, or does anyone have some ideas what this could be. Thanks.-Andrew c ^[talk] 18:03, 9 September 2008 (UTC)

Rhododendron perhaps? They're rather common in the area you mention... Arakunem^Talk 18:09, 9 September 2008 (UTC)

That would be my guess. --Tango (talk) 18:29, 9 September 2008 (UTC)

That's a good guess, but not it :) The leaves are not quite that elongated, and the flowers are individual buds, not bunches of flowers (the rhododendron flowers look more similar to bunches of azalea flowers, where the plant I'm talking about has a single large bud and looks like something that may be on a corsage). Plus I'm not sure rhododendron has the serious serrations on the edge of the leaves. Any other ideas? Thanks for the suggestions so far.-Andrew c ^[talk] 18:32, 9 September 2008 (UTC)

Peony?

All the peonies I've seen (which admittedly are in the Great Lakes region) are far smaller than this plant. A pity, because the rest sounds right for a peony. Nyttend (talk) 19:43, 9 September 2008 (UTC)

Wait, "all around": what does this mean? If you mean that the circumference is four or five feet, that would be quite reasonable for the peonies I've seen. Nyttend (talk) 20:18, 9 September 2008 (UTC)

Some kind of magnolia? I'm not aware of one with serrated leaves, but ... ? --ColinFine (talk) 20:06, 9 September 2008 (UTC)

Camellia or Azalea? DuncanHill (talk) 20:52, 9 September 2008 (UTC)

DING DING DING! We have a winner. Camellia it is (or at least I'm pretty sure). Thanks!-Andrew c ^[talk] 00:29, 10 September 2008 (UTC)

If it's Camellia sinensis you could make tea! DuncanHill (talk) 00:58, 10 September 2008 (UTC)

Blue-yellow colourblindness

Is the colouring for the attached image likely to be a problem for blue-yellow colourblind people? I know there's a potential problem for red-green people (I myself am one), but I've done the best I can by making the blue/purple and red/green borders as short as possible. Nyttend (talk) 19:40, 9 September 2008 (UTC)

I'm not blue/yellow color blind, but at the end of the article color blindness there is a link to a website "Colorblind Web Page Filter", which allows you to simulate a webpage for different types of color blindness. Check it out yourself, but for blue/yellow blindness, your picture seems to look fine. -- 128.104.112.147 (talk) 20:36, 9 September 2008 (UTC)

Actually, there is more than one kind of red/green colorblindness (I think at least three or four). But the thing is that even if you are totally colorblind, you can still distinguish brightness. Yellow is a much brighter color than "computer-screen-primary" blue - so even utterly "every-color"-blind people who can only see in shades of grey will be able to see the difference between primary blue and primary yellow. However, if you'd chosen a brighter shade of blue - or a darker yellow - it would not have been so clear. My son is red/green colorblind - but he can easily tell the difference between red and green - even if they are at the same intensity because his particular variation is that he has a weak red sensor. His problem is between more subtle hues between red and green - and he has a lot of trouble telling red from orange or (to a lesser degree) orange from green. Our article lists at least seven different variations on color blindness - two of those are yellow/blue-related. But the colorblind web page filter is an excellent resource for the normally-sighted to get an idea of what your graphic will look like to each of the different variations. SteveBaker (talk) 20:56, 9 September 2008 (UTC)

A nice and probably easy MediaWiki hack would be a module that warns you when you upload an image with only a few colors that they're not colorblind-friendly and suggests a substitute pallet with brightness variations. --Sean 21:11, 9 September 2008 (UTC)

It looks okay with protanopia, deutanopia, or tritanopia. If you are concerned, you can test images yourself at this site. It also has some tips for building color-blind accessible web pages. Plasticup ^T/C 02:17, 10 September 2008 (UTC)

Thanks for the various comments: I'd not considered the brightness factor. I'd appreciate the filters, except that (as I noted above) I'm somewhat red-green colourblind (although I'd never read the article, and thus never knew that there were multiple types; I just thought it varied in intensity), so I don't know whether I'd be able to make productive use of them. Nyttend (talk) 05:28, 10 September 2008 (UTC)

And for the, ahem, rest of us? Those colors? Please. No. Saintrain (talk) 00:20, 11 September 2008 (UTC)

NOAA weather radio voice

All,

The voice of the NOAA weather radio was previously known as "Paul" (which sounds somewhat like "Mike" from MS TTS). The current one is known as "Tom." I was listening to a local stream of the NOAA All Hazards Weather Radio; who is the voice for this [3] one? The voice sounds like neither "Tom" nor "Paul" (see this [4] to listen to samples).

jdstroy (talk) 20:30, 9 September 2008 (UTC)

Weather or not

Was San Francisco overcast on August 14, 1972?

Wanderer57 (talk) 23:21, 9 September 2008 (UTC)

The more important question is where such information may be looked up. Wanderer57 (talk) 23:40, 9 September 2008 (UTC)

Such records certainly seem to exist [5], but it looks like you would have to go to Washington to look them up, they don't seem to be on-line. [6] Franamax (talk) 00:02, 10 September 2008 (UTC)

That's so cool! It's there! And all I had to do was "san+francisco"+weather GOOGLE it! Saintrain (talk) 00:04, 10 September 2008 (UTC)

Specifically, here. Saintrain (talk) 00:07, 10 September 2008 (UTC)

Dang! I forgot about weatherunderground. It doesn't say if it was overcast though ;) Can you infer that from the visibility? Franamax (talk) 00:36, 10 September 2008 (UTC)

(Sheepishly) Yes, but also from the temperature, humidity and steady 15 kt wind and it was the middle of August. But you know what Mark Twain didn't say?. (I do remember his story about the S.F drunk who froze to death under a blooming rose, though, don't I?) Saintrain (talk) 01:50, 10 September 2008 (UTC)

I clearly remember that a few years ago, I somehow missed an occultation I was planning to time and later tried to determine whether I could have seen it. I found a site that listed the temperature, cloud cover, and other conditions for every hour. I can't remember how far back the archives extended or whether they covered any city except my own (the Greater Toronto Area). I also can't seem to find it again. --Bowlhover (talk) 04:20, 10 September 2008 (UTC)

Ah, another datum for my planned great-identity-stealing machine, Bowlhover is a Hogtowner! Please tell, haven't you just had a record-setting amount of rainfall in my dear departed province? Franamax (talk) 06:15, 10 September 2008 (UTC)

Thanks. The METARS information link available at the bottom of the weather underground page gives the sky condition as scattered cloud and broken cloud, but not overcast.

Wanderer57 (talk) 13:15, 10 September 2008 (UTC)

PS - Is there any weather underground? Very high pressure and overcast would seem to be the normal condition.

Warm, humid, occasional drizzle. DuncanHill (talk) 14:56, 10 September 2008 (UTC)

So what's so special about San Francisco on August 14, 1972? Dragons flight (talk) 14:59, 10 September 2008 (UTC)

I don't know. I asked about the weather on that day in SF because of another editor asking what phase of the moon was seen in San Francisco that day. Wanderer57 (talk) 15:15, 10 September 2008 (UTC)

It's possible that it's the day the person was born/married/parents married/whatever. I can imagine the phase of the moon will mean something to those who believe in astrology. I've never heard of anyone caring about what the weather was like though Nil Einne (talk) 11:42, 12 September 2008 (UTC)

Global Warming

I've been thinking: wouldn't inducing a rapid growth of algae or something similar in the world's oceans (by putting large amounts or iron or something similar) make considerable progress in reducing the carbon dioxide content or the atmosphere? Before you ride me off, I think I remember reading on Wikipedua (I can't find the article) that a certain algae, because they were found in such large numbers, caused an Ice Age.

It's phosporous. I think algal blooms are not that appreciated.--Lenticel ^(talk) 23:35, 9 September 2008 (UTC)

The problem is that algae pretty much shut out all of the other lifeforms - so sure you'd maybe reduce CO2 - but maybe you'd also kill off all of the fish. The problem with all of these "radical" solutions is that we don't have a good enough understanding of the consequences of doing them. It's very likely that we'd make matters much worse. SteveBaker (talk) 23:39, 9 September 2008 (UTC)

It is iron that the OP's thinking of, and we have an article: Iron fertilization. -- 128.104.112.147 (talk) 23:41, 9 September 2008 (UTC)

I see, but according to the article it is still in the experimental stage. However, we could already see the effects of the human induced algal blooms.--Lenticel ^(talk) 23:51, 9 September 2008 (UTC)

It is experimental because we don't yet know all the effects, such as whether the carbon actually gets sequestered to the ocean floor, and what the nasty side effects might be, such as creating anoxic regions, as Steve notes. If you email me, I can send you a few papers and articles from Nature. Franamax (talk) 00:05, 10 September 2008 (UTC)

On a side note, and for your future information, and I'm not grammar naziing, but just letting you know, the phrase is "write me off", not "ride me off". --Sean 00:29, 10 September 2008 (UTC)

Oh wow, you don't know how long I've been using ride... —Preceding unsigned comment added by 65.92.231.82 (talk) 03:40, 10 September 2008 (UTC)

Also, algae can be poisonous, for example red tide or the poisonous algae found in Quebec lakes last year. ~AH1^(TCU) 00:55, 14 September 2008 (UTC)

Antimatter

Hello. I'm a high school student interested in physics and have just read about the concept of antimatter. Unfortunately I got lost very quickly in the preface of the article on this subject and am having real difficulty grasping in my mind the concept of antimatter. could somebody explain it very simply to me, perhaps with a helpful illustration? 79.75.199.175 (talk) 23:54, 9 September 2008 (UTC)

Have you read antiparticle? I think we're going to need to know what it is that's confusing you particularly, otherwise we're going to end up explaining it the same way as the articles. --Tango (talk) 23:56, 9 September 2008 (UTC)

Well as i understand it antimatter is the opposite of matter, so one would assume antimatter does not have mass while matter does. However i'm not sure if particles such as photons which have no mass are considered antimatter so i might be wrong in my understanding here. If matter is "stuff" then is antimatter is "non-stuff" which also takes up space or what? 79.75.199.175 (talk) 00:23, 10 September 2008 (UTC)

Matter has many properties, and antimatter certainly doesn't have the opposite property of each of them. In particular, it has mass. --Sean 00:32, 10 September 2008 (UTC)

Photons indeed have no mass, and are not normally considered to be either matter or antimatter. Algebraist 00:34, 10 September 2008 (UTC)

Specifically, antiparticles have the same mass as their matter counterparts; they just have opposite charges. I believe charge is the only difference between matter and antimatter. --Bowlhover (talk) 04:29, 10 September 2008 (UTC)

No, other quantum numbers such as spin and colour charge are also reversed in an antiparticle. If only the (electric) charge were reversed then the antineutrino would be identical to the neutrino. Gandalf61 (talk) 10:59, 10 September 2008 (UTC)

There is no real difference between matter and antimatter overall (well, there might be if you get to really complicated stuff, but that's not important to start with), there is only a difference when you compare a particle with its antiparticle. For example, some matter is positively charged (eg. a proton) and some is negatively charged (eg. an election). Likewise, some matter is positively charged (eg. a positron [anti-electron]) and some is negatively charged (eg. an anti-proton). So, it's not that matter has one property and antimatter has the other, that only applies for a particular particle/anti-particle pair. --Tango (talk) 00:38, 10 September 2008 (UTC)

Did you mean 'antimatter' in the 3rd sentence? Wanderer57 (talk) 01:53, 10 September 2008 (UTC)

Adding onto the concept of symmetry between matter and antimatter, why the Big Bang didn't form an equal amount of the two was a mystery until CP-violation was discovered. --Bowlhover (talk) 04:29, 10 September 2008 (UTC)

Matter is a poorly defined word. It usually means anything that has mass and takes up space. By this definition, antimatter is not the opposite of matter; it's just a confusingly-named kind of matter. (And, for that matter, antiparticles are not the opposite of what we usually call particles; they're just confusingly-named kinds of particles.) --Allen (talk) 00:53, 10 September 2008 (UTC)

Perils of Modern Living

Harold P. Furth

Well up above the tropostrata

There is a region stark and stellar

Where, on a streak of anti-matter

Lived Dr. Edward Anti-Teller.

Remote from Fusion's origin,

He lived unguessed and unawares

With all his antikith and kin,

And kept macassars on his chairs.

One morning, idling by the sea,

He spied a tin of monstrous girth

That bore three letters: A. E. C.

Out stepped a visitor from Earth.

Then, shouting gladly o'er the sands,

Met two who in their alien ways

Were like as lentils. Their right hands

Clasped, and the rest was gamma rays.

SteveBaker (talk) 02:05, 10 September 2008 (UTC)

That reminds me of a haiku:

Hippopotamus

Antihippopotamus

Annihilation Algebraist 02:09, 10 September 2008 (UTC)

well, last night i went to an italian restaurant and ate antipasto followed by pasta, and there is definitely a vast quantity of energy being liberated as they meet. Gzuckier (talk) 16:41, 10 September 2008 (UTC)

You forgot to quench the reaction with a nice stinky grappa then... Franamax (talk) 03:43, 11 September 2008 (UTC)