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I've known for a long time that in the sun four hydrogen atoms fuse to make a helium atom. I never really thought about it much, but just recently I realized that four protons fusing together should make beryllium, not helium. I read some of the article Nuclear fusion and it had a pretty cool pic...Image:FusionintheSun.png, but I didn't understand most of it. Also, the pic shows the creation of a positron. What in the heck is a positron? (Supposedly the anti-matter of an electron, whatever that means) Lol! Again, over my head. Anyway, I was just wondering. Thanks to everyone in advance!
Dimblethum03:14, 1 December 2005 (UTC)Dimblethum[reply]
I'm not a physicist, but the figure seems to indicate that you can produce a neutron by releasing positron from a proton. A positron is the antiparticle of an electron. --JWSchmidt03:35, 1 December 2005 (UTC)[reply]
That's also right, there's also a neutrino involved, but they're pretty damn hard to see. There are two weak decays that affect nuclei, and they are:
You're correct that four protons in a nucleus would make beryllium; however it is more complicated than that; a nucleus with four protons and no neutrons would be highly unstable. The reactions are detailed in proton-proton chain reaction and are too complex for me to fully explain here, but I'll try summarize. The key is the initial proton-proton reaction. Two protons come together, and one proton is converted into a neutron (an up quark transforms into a down quark I believe). In the process, a positron is emitted, which as JWSchmidt indicates is the antiparticle of an electron (see that article, or antimatter if you are not familiar with the concept—basically each particle has a corresponding antiparticle with opposite charge, spin, etc.; when a particle and antiparticle collide, they annihilate each other and produce energy via E=mc2. This, for instance, is the basis of the matter-antimatter reactor that powers the Enterprise in Star Trek and in other science fiction. Antiparticles are normally simply named by adding anti- to the particle name; positrons are a historical exception). Also emitted is an electron neutrino. The positron will quickly meet an electron and mutually annhiliate. The rest is covered in proton-proton chain reaction; if there are specific questions you have or concepts you don't understand, ask them here. — Knowledge Seekerদ03:47, 1 December 2005 (UTC)[reply]
All stable nuclei have a ratio of protons to neutrons that falls within a certain range (see Isotope table (divided)). If there are too many protons, some can turn into neutrons by beta decay, and vice versa. A proton can change into a neutron by emitting a positron (beta plus), and a neutron can change into a proton by emitting an electron (beta minus). —Keenan Pepper03:59, 1 December 2005 (UTC)[reply]
Electrotheremin construction
I'm looking to build an electrotheremin, which as I understand it is just an audio oscillator with a slide potentiometer determining pitch. However, I don't really have experience with electronics, so I can't just "wing it." Is there a place on the internet or something where I could find the schematic for such an oscillator? Or, is there a simple step for replacing a resistor in an existing oscillator circuit with the slide potentiometer? Thanks in advance. --ParkerHiggins03:17, 1 December 2005 (UTC)[reply]
Yes, if you already have an oscillator circuit you could replace the resistor with a slide potentiometer. Or even simpler, you could just add the potentiometer in parallel with the resistor, which wouldn't require breaking the original circuit. —Keenan Pepper15:24, 1 December 2005 (UTC)[reply]
Insulin Structure
Hi. Im doing a school project for my grade 12 biology class and I need to make a physical insulin structure. Within my sructure, needs to be the appropriate sequence of amino acids to form an insulin protein. So far, the types of insulin structures I've found on the web consist of the "leader chain, A-chain, B-chain, and C-chain". These descriptions are not what Im looking for. I need to know the exact sequence of amino acids in these chains that make up insulin.
Thank-you very much for your help.:)
See this page. The structure shown is cow insulin; if you want to make a model of human insulin be sure to make the substitutions shown at the top of the page. You also have to decide on what form of insulin you are modelling: the kind that is found in the circulation (insulin proper, which is shown there) or the one which is transcribed from the RNA and processed to become that form (proinsulin). The leader-chain and C-peptide won't be found in the circulating form. (BTW, searching for "insulin amino acid sequence" would find this for you). - Nunh-huh03:54, 1 December 2005 (UTC)[reply]
Any conductive material, if wrapped around the appliance without large holes, forms a Faraday cage that blocks low-frequency electromagnetic radiation. The maximum allowable hole size depends on the highest frequency that needs to be blocked. —Ilmari Karonen (talk) 16:55, 1 December 2005 (UTC)[reply]
middle cerebral artery aneurysm
How can I treat a middle cerebral artery aneurysm?
Well, I advise you seek professional help on this one. All I can do is mention the treatment section of aneurysm, and point out also the article on cerebral aneurysms. I didn't notice either of them specifically mentioning middle cerebral artery aneurysms. --ParkerHiggins07:17, 1 December 2005 (UTC)[reply]
How can one convert a .m4a file format (songs from iTunes) to *.wma file format (so i can play them in windows media player...)?
There's a winamp plugin that lets it play m4a. So you can use winamp to play them, or you can use winamp to decode it to a wav (and then you can use any of a dozen programs to reencode it as an mp3) Raul65410:58, 1 December 2005 (UTC)[reply]
Does anyone know why the term "cookie" was used in the first place? (I can see the link for developing the brownie project, but why did he choose "cookie" to start with)?
All ideas gratefully accepted.
Jax1402
I have a magnetic base for a measuring device that allows you to attach the measuring device to metal objects. The magnetic base has a switch that allows you to turn the magnet on or off. When on, the magnet is very powerfull, and when off, it will attract and hold a paper clip but nothing bigger.
I dissassembled the magnetic base on found that it consists of a block of metal with a cylindrical hole drilled thru its center. In the hole is a cynlindrical magnet. The switch rotates the cylindrical magnet 90 degrees. The outer block does not have any measurable magnetism.
Your description is a bit value, but I'll assume the dipole axis of the magnet is perpendicular to the axis of the cylinder, i.e. that rotating the magnet in the hole moves the poles, and that in the "on" position one of the poles points towards the bottom of the base. That pole then strongly attracts adjacent ferromagnetic objects. When you rotate the magnet 90°, both poles as now facing the sides of the base (where there is presumably quite a lot of padding between the magnet and the exterior of the base), while the side of the magnet produces only a weak residual attraction. —Ilmari Karonen (talk) 16:44, 1 December 2005 (UTC)[reply]
Actually, it's usually the opposite way around. When the magnet is "off", the dipole points up and down. When it is "on", the rotating magnet has its N pole in one half of the base, and the S pole in the other half. The two halves of the base plus the rotating magnet form a sort of horseshoe magnet. When its attached to a piece of metal (across the two halves of the base) it makes a magnetic circuit which it is very strong. When it is switched off, there's a much smaller residual magnetism. These sort of bases are used a lot in optical experiments to position devices on optical benches. See here: U.S. patent 4,251,791 for one design. --Bob Mellish21:34, 1 December 2005 (UTC)[reply]
I agree with Eye - what you want to do is to disrupt the alignment of the dipoles in some manner. Nothing quite like heating or hitting the magnet. --HappyCamper03:32, 3 December 2005 (UTC)[reply]
Last week an article about a guy with a dozen satellite dishes outside his house was linked everywhere on the internet. This morning I stopped by my mothers house and they recently had their DirectTV dish replaced with one that can pick up local channels. They got to keep their old dish...until I stole it from them. What do I need to do to set this sucker up on my apartment balcony and start getting news feeds, local channels from other states, and shows in languages I don't speak?
I know I need a receiver but could I just use a computer and some software made for this?
Is there any other fun things I can do with this dish?
what is the maximum number of vertices with 15 edges and three components?
If you have V vertices and E edges, the minimum number of components is V − E (because if there are no edges, each vertex is its own component, and each new edge can only reduce the number of components by one). In this case we need , so the maximum value of V is 18.
Today I took of water from a water fountain. After I had lowered my head towards the faucet, I could smell cleaner fumes. This upset me because I inhaled the fumes while being close to the source of the fumes. I'd like to know if this is the equivalent of huffing, because I'm scared of being brain damaged from the fumes.
Wikipedia does not generally give medical advice, so if you're really worried, go talk to your doctor. However, I suspect it was harmless. The effects of inhalants are usually acute rather than chronic, which means you get dizzy and even pass out before doing any permanent damage (unless it becomes a habit, of course). —Keenan Pepper18:32, 1 December 2005 (UTC)[reply]
I think there are bigger problems if your water fountains are producing fumes. Water vapor is not a fume, nor ought it to have a smell. --YixilTesiphon06:19, 2 December 2005 (UTC)[reply]
If you live anywhere near a sizeable built-up area you'll likely be inhaling exhaust fumes all the time (every breath you take, day and night). Living next to a busy road is like being a heavy smoker. I base this on tests done on children in Maastricht, not quite a big town. The traffic is nothing compared to that of a modern big city, let alone the ones in the US (eg LA) or third world countries. If you want to worry about something worry about that. DirkvdM10:43, 2 December 2005 (UTC)[reply]
How Does An Alkaline Component of Laundry Detergnets and Cleaners Clean
How does an alkaline/base component of detergents and cleaners make a stain more soluble? In other words, how does it dissolve the stain?--Just Wondering
This is sort of a trick question, because it really depends on the chemistry of the laundry detergent. Which brand are you using? --HappyCamper03:29, 3 December 2005 (UTC)[reply]
For some reason the Wikipedia search engine that came with the previous version of Mozilla's Firefox browser (I'm using the most recent update) is now gone! Why is that, and does the company plan on bringing it back? I can't seem to find a place to ask at its website. --71.103.127.11400:18, 2 December 2005 (UTC)[reply]
You can add the Wikipedia search engine plugin by clicking on the "Wikipedia" link on the following page: Search Engines. Be sure you have javascript enabled. You can also go to the same page by selecting "Add Engines..." from the drop-down list in the Firefox search box. -- Mark Bornfeld DDS dentaltwins.com Brooklyn, NY 01:07, 2 December 2005 (UTC)
According to Robert Burnham, Jr. in Burnham's Celestial Handbook, Hercules was one of the earliest star patterns to be defined and was identified with national heros or gods from very ancient times in the Near East. Burnham says that in Mesopotamia the star group was associated with the sun-god Izhdubar, the legendary hunter Nimrod, and with Gilgamesh of the flood legend. The ancient Phonecians saw it as the god Melkarth. Later, in ancient Greece, the constellation came to be associated with the hero Heracles, or Hercules. It's unlikely that it will ever be known exactly "why" this constellation was identified with a god or hero originally, but given that history, it is understandable that the Greeks came to name it for their great national hero. --DannyZ06:08, 4 December 2005 (UTC)[reply]
Extracting information from the web (datamining)
How would I go about writing a program to extract data from a website (ie the sales rank of books on amazon.com)?
In principle, you'd write a program that simulated a browser connection to fetch information from a web site, perhaps using URLs you list in advance, or a web spidering system. Then you'd parse the HTML, assuming unchanging formats, to get the book info and rank. Then analysing it would be easy. In practice, if you plan to get all books rather than just a handful, this would hit Amazon's servers hard (perhaps as hard as thousands of customers). They are likely to have methods in place to detect this, assume they are under attack, and block your connection temporarily or permanently. Not recommended. Notinasnaid09:41, 2 December 2005 (UTC)[reply]
Not sure what you mean, but HTTrack will let you download the entire Internet if you wish. Careful though, it's extremely powerful and you may get more than you bargained for. DirkvdM10:49, 2 December 2005 (UTC)[reply]
It's also good to check if the website has an RSS feed available that you can easily extract data with; PHP has some good XML parsing functions you could use. Though if Amazon doesn't issue RSS i'd suggest the above. -Benbread15:40, 2 December 2005 (UTC)[reply]
Can the use of mobile phones by pregnant woman, can harm the fetus?
Sir/Madam,
Iam Sudha, from Tamil Nadu,India.
If a pregnant women, who uses cell phones / mobile phones in her daily life, will the fetus (unborn baby)inside her will be affected if she continues using cell phones?
Can you please answer this question, as early as possible?
According to Mobile phone radiation and health, the risk of radiation from cell phone use is, as yet, unsubstantiated. However, as the article says "the World Health Organization has recommended that the precautionary principle could be voluntarily adopted in this case." So, I would say that the baby will be fine, provided the mother isn't always on the phone. I hope that helps to answer your question. --ParkerHiggins07:04, 2 December 2005 (UTC)[reply]
Even if phones provide a health risk, the radiation it cause is only powerful enough to reach the woman's own brain which shouldn't have any direct influence on the fetus. Of course, effects on the mother will eventually affect the child psychologically if they turn out to be severe in the long run. I would recommend cutting down phone usage anyway. - Mgm|(talk)09:40, 2 December 2005 (UTC)[reply]
No, the solubility of most gases (I want to say all gases, but there may be weird exceptions?...) decreases as temperature increases. A common example of this is carbonated water, which quickly goes flat on a hot day but keeps its carbonation for a long time when chilled. The reason for this is that, at a higher temperature, the gas particles move faster, and they can more easily escape from the surface of the solution (the vapor pressure is higher). So, the capacity of hot water to contain dissolved air is less than that of cold water. —Keenan Pepper18:47, 2 December 2005 (UTC)[reply]
Bad phrasing on my part. Gasses are already dissolved (unless they are forming bubbles), so Suprm401's question doesn't make any sense. --YixilTesiphon03:16, 3 December 2005 (UTC)[reply]
Huh? Let's take a step back and see:
Does hot water contain air more than cold water? The answer is no - this is because the solubility of air (ie, mostly nitrogen and oxygen) in water decreases as you increase the temperature. Keenan's example of soda is an excellent everyday example of this general observation - hot coca cola certainly doesn't have quite the fizz as a cold one! Ditto with beer.
As for the ice cubes - that's also the reason why boiled ice cubes look clearer - during the boiling process, most of the dissolved gasses escape. Hence, when you make ice cubes, no bubbles come out during the freezing process.
An alloy is an example of a solid solution. And yes, things can "dissolve" in a solid - however, it's a bit more of a subtle concept here. In this case, it depends on how you define "dissolve" - it may not necessarily mean "solvation". However, in certain fields of chemistry, it is desirable to restrict the definition to liquid solutions. I hope this clarifies things! --HappyCamper03:23, 3 December 2005 (UTC)[reply]
Almost forgot: REgarding Superm401's question - yes, some air will redissolve back into the water when it cools, but the difference is that the rate of freezing is significantly higher than the rate at which the air dissolves. --HappyCamper03:24, 3 December 2005 (UTC)[reply]
They look clear because the freezing is incremental - but if you slice one, you will notice that there is a tendency for these bubbles to form in the center...so I guess they aren't really clear... --HappyCamper03:40, 3 December 2005 (UTC)[reply]
A common practice indeed for children in the northeast US anyway. Icicles from roofs in particular because they can get pretty big. --hydnjotalk15:51, 3 December 2005 (UTC)[reply]
Ironically the picture at the bottom of Ice shows icicles formed on a roof in Australia, even though I live in Austrlaia (and have never seen snow/ice) and was unware of the use of icicles.--Commander Keane17:56, 3 December 2005 (UTC)[reply]
What happens when a liquid is inserted between a convex lens of focal length 20 cm and a plane mirror?plz give a detailed answer.
There's no general answer; it depends on the liquid (in particular its refractive index), what material the lens is made out of, the exact form of the lens (e.g. radius of curvature of each surface), and the distance between the lens and the mirror. Very roughly, adding the liquid will increase the optical path length between the lens and the mirror; but the exact effect will depend on the parameters above. --Bob Mellish17:36, 2 December 2005 (UTC)[reply]
What do you mean by inserted? Is a tank of water placed between the lens and the mirror, or is the whole setup submerged in water? It makes a big difference. —Keenan Pepper18:58, 2 December 2005 (UTC)[reply]
Do your own homework. It's a little offensive when you give exact numbers (thus indicating that this is a homework problem), and say "plz give a detailed answer." --YixilTesiphon00:14, 3 December 2005 (UTC)[reply]
Hmm..."offensive" might be going a little bit over the top here I think. We need more background information about the question in order to help you better. Are you trying to find the effect of looking through the combination of lens-water-glass, as opposed to lens-air-glass? --HappyCamper03:15, 3 December 2005 (UTC)[reply]
Order and names of the Periodic Table groups
Hey
There seems to be some dispute over the numbers of the groups in the Periodic Table - I live in the UK and i've always been taught there are groups 1-0/8 and the transition metals, with these being named because of the number of electrons in their outer shell. While wikipedia and other sources state there are 18 groups. I'm assuming that the 18 groups is correct, but where is there some difference of opinion among people?
Well, looking at periodic table I discovered, as I hoped, a section explaining this, albeit briefly. Basically, it seems the 1-8 plus transition metals scheme isn't entirely unambiguous, so is officially "deprecated" by the shadowy bodies that get to decide such things... - IMSoP19:48, 2 December 2005 (UTC)[reply]
The naming isn't so much a "dispute" - it is more a reflection of our better understanding of chemistry from a quantum mechanical perspective. In particular, the IUPAC recommended the renaming a few years ago. The old grouping of systems is still useful for teaching purposes though. --HappyCamper03:14, 3 December 2005 (UTC)[reply]
illness
i am a 44 yo female i was diagnosed 3 years ago with rsd, since then i have been diagnosed with ulner noropathy degenerative disc disease rhumatoid arthritis(severe 242) fibromyalgia have bulging disc in c4567 and sudden platelett count drop any ideas. drs here are stumped and cant seem to offer any new help. you may e-mail me at <email removed>
Please read the instructions at the top of the page. Leaving your email address here will almost certainly gets you loads of SPAM. - Mgm|(talk)22:09, 2 December 2005 (UTC)[reply]
I am sorry for your combination of problems, which sounds like way more than any one person deserves. It is difficult to give you a simple answer to your question for many reasons:
You may actually have a combination of problems and there is no unitary answer to be had. It is always more gratifying for both patient and doctor if a single disease can be recognized that explains all of a person's problems, but that is unfortunately the exception rather than the rule.
But having said that, it is still likely that some of them are connected to each other, statistically if not causally. For example, a common cause of platelet drop (thrombocytopenia) can be a drug effect. Have you started anything new recently? You might want to check whether thrombocytopenia is listed as a side effect of any of the drugs you take. That doesn't prove a causal relationship, but it gives you some choices of what to do. Another cause of sudden platelet drop is a viral illness. The platelets usually return to normal within a couple of weeks. Some people can develop autoimmunity to their own platelets, especially when they have other autoimmune or inflammatory diseases like rheumatoid arthritis.
If you have not asked your primary doctor for referral to a rheumatologist you might try that. They get lots of people referred for mysterious inflammatory conditions.
You know when you type in the name of something and save it and it says 'do you want to replace the article of the same name', is there any way you can get the article you deleted back? Its very important and I couldn't possibly do it again. Thanks! ----XenoNeon18:47, 2 December 2005 (UTC)[reply]
Doubtful. Try searching and see, maybe it's stored somewhere in temp files (remember to look in hidden and system files), but you're in bad straits here. --YixilTesiphon13:34, 3 December 2005 (UTC)[reply]
Norton Antivirus 2004 offers a recycle bin which 'catches' and files deleted by whatever means (even non-manual) technically the file will probably still exist on your hard drive, but recovering it can be difficult and expensive, however, if the file is very important it is probably worth looking into professional help to recover it. The police use this method all the time, if a file is deleted it will still exist on your harddrive, however, the more times it is overwritten the harder and more expensive it is to recover it. - Unregisterd User 18:13 3 December 2005
A Question regarding paraffin...from e-mail address removed
Where can one purchase paraffin for arthritic joint therapy, and about how much does it cost?
All I'm really asking is, how did all these dangerous epidermic happened? I mean, if we could go back in time, and say there are 100,000 males and females divided equally, all are all healthy individuals, how can STI and AIDS (or HIV) happened/started??
The answer is in evolution and mutation. Depending on how far back you want to go, we could assume bacteria, viruses, and protozoa exist (for simplicity we'll ignore multicellular organisms that live as parasites). Mutations in these agents can alter their virulence and transmission (medicine)--that is, the amount of damage they do and their ability to move from one host to another. As such, a virus or retrovirus that infects one type of organism could mutate to infect humans. This is believed to be the origin of the HIV strains that infect humans (see AIDS article) and is the crux of the recent global fear of an avian influenzapandemic.
The origins of infectious disease in general are older and less clear. But biological interactions are as old as life itself, and are seldom friendly (see food chain). Viruses may have arisen from a bit of host genome mutated to produce large amounts of a virion even at penalty to the host.
IlliniWikipedian is absolutely correct. There was likely no time in the past where the entire population was disease-free. Bacteria and viruses predate the origin of humans. Disease is ancient. Our primate ancestors had infections before we evolved. Furthermore, even suppose you were granted a wish and you wished all disease-causing entities to instantly die, it would not be the end of (infectious) disease. Vast niches would now be free, and it would only be a short time before some of the remaining, innocuous bacteria evolved to parasitize and cause disease in humans and other organisms. With regards specifically to HIV, the virus that causes AIDS: there is a related virus, a simian immunodeficiency virus, which causes an AIDS-like disease in monkeys. One strain of this was transmitted from chimpanzees (our closest relatives) to humans in sub-Saharan Africa and evolved into what we now call HIV-1, the predominant form of HIV. A different strain evolved into HIV-2, which still only exists primarily in Africa. — Knowledge Seekerদ23:10, 2 December 2005 (UTC)[reply]
A problem here might be black and white thinking, the idea that certain organisms are purely bad. Where organisms live together they are likely to start interacting in some way. Sometimes this will result in one predating on the other, not with malicious intent, that's just the way things work. These we then call diseases when they're small (unless we want to consider ourselves a disease for the world's population of cows and such). At other times the interaction will be to the benefit of both, which we then call symbiosis. These interactions will always have happened, so there will always have been and always will be diseases (as already pointed out). DirkvdM09:53, 4 December 2005 (UTC)[reply]
Help figuring out the components of a chemical reaction
Once I was flipping through a book of chemistry abstracts. I found one that described a reaction, the by products of which where C02 (sry don't know how to make subscript) and ethanol.
There was some discussion following that it could be used to make alcoholic soda pop tablets.
(Reagents + Flavoring)Compressed into a tablet + Glass of Water = Adult Soda.
I saw this year ago, and have gone back to the science library and tried to find it, but to no avail.
Does anyone have any idea what would have been used?
Are you thinking of the powdered 'alcopop' beverages being sold in Europe? One of the brand names is Subyouwww.subyou.com, but I imagine that there are or will be others.
My understanding is that the powdered just-add-water beverage is based on ethanol encapsulation. Droplets of mixed water, ethanol, and starch (dextrin or the like—something water soluble and flavourless) are dried under controlled conditions. The starch traps most of the ethanol molecules but allows the smaller water molecules to escape. The 'dry' Subyou powder is about 30% ethanol by weight. Adding water redissolves the dextrin and releases the alcohol back into solution. There are several variations on this encapsulation scheme.
As YixilTesiphon mentions above, there are lots of chemical reactions that will generate CO2 when you add water. A powder containing a mixture of dry acid and dry carbonate or hydrogen carbonate (bicarbonate) compounds will certainly do it. TenOfAllTrades(talk) 01:16, 3 December 2005 (UTC)[reply]
I think the powdered alchopop thing is closer to what I was thinking of. It was years ago that I saw it, but in my memory the chems in it actually reacted in solution to produce the ethanol and the CO2. That may not have been hte case though.
"Point" might be misleading, because it's fairly arbitrary: "When glass has been heated to a high enough temperature, it must be cooled by a controlled schedule of time and temperature or it will crack simply because of the strain inside the glass from the outside cooling faster than the inside. The sound of cracking glass in the waste buckets is common in glass studios. The thicker the glass, the longer the cooling time must be, days and weeks in the case of really thick castings. The annealing temperature is determined by slowly heating a long thin piece of glass supported at the ends until it just starts to sag (the sag temperature) and the annealing temperature is taken to be 50°C (90°F) below that, usually about 900F (480C). When scientific measurements are possible, the annealing point is a specific viscosity. "annealing point, AP—the temperature corresponding to a rate of elongation of 0.0136 cm/min when measured by ASTM Method C 336, Test for Annealing Point and Strain Point of Glass by Fiber Elongation. This test prescribes a rate of cooling of approximately 4 C/min with a fiber of approximately 0.065 cm in diameter, and a suspended load of 1000 g. The annealing point numerically approximates log = 13.0 poises, where internal stress is substantially relieved in a few minutes."" [3] - Nunh-huh23:48, 2 December 2005 (UTC)[reply]
Hi, I'm helping my daugther with a tree project-Red Maple Tree and there are a few questions we needed to research to be able to do this project. First of all we had to pick a tree in our area to do the study on (Red Maple Tree). 1.How do you estimate the age of the tree by it's circumference? 2.The tree's habitat would be what (Where we live?)? The Red Maple's connection to technology and human wants and needs? 3.And very important the lif cycle of R.M.T.-this is a must have, all we could find are a basic tree cycle not necesary for R.M.T. And any other useful information that we could use in her report and Hypothesis-whether it blossoms flowers and what the seeds look like. We did find some general info, but not enough.
Thank you so much for any information that you can provide. 12/2/05--71.66.123.248 posted 00:33, December 3 2005 (UTC)
Here are a couple of places to start where I found nice pictures of all the parts of red mapels: seeds, leaves, bark, etc. [4][5] The habitat is where it is likely to be found in the wild, something like "northern temperate zone hardwood forest". Estimating the age from tree circumference can be done by finding a table of typical annual thickness increases for particular tree species [6][7]. Or you can find a stump of a red maple, count the rings, and divide the radius by the number of rings to get the usual increase in diameter per year (remember diameter is twice radius). The circumference is about 3.14 x the diameter [8]. Or you could call your state forestry service and ask if they can tell you how to do it. Good luck. alteripse01:09, 3 December 2005 (UTC)[reply]
I like "If you know when the tree was planted, you can easily and accurately determine its age." at [9]. The list members at [10] apparently believe width is not a very good measure of age. I'm inclined to think alteripse's suggestion of contacting the state forestry service might be better. Your IP indicates you live in Virginia, so the phone number of the Virginia Department of Forestry is 434.977.6555 . If you don't, you can look it up. Superm401 | Talk02:45, 3 December 2005 (UTC)[reply]
Baby Tortoises
Esmé, a South African reader has sent the following question to the Wikimedia Help mailing list.
Please could you find out for me whether there is a specific term for a baby tortoise – so far the only term which has been presented is “baby tortoise” – surely there must be a more specific term?
I have advised her that it seems to be commonly used but I would be grateful if anyone could offer additional suggestions.
According to dictionary.com the baby turtle is called a hatchling. They don't have an entry for tortoises, but maybe that can be used for them as well? I expect it could be used for anything that hatches out of an egg. It does say what the collective noun for a group of tortoises is: a creep. I didn't know that, that's fun. -lethetalk02:41, 3 December 2005 (UTC)[reply]
UHF Radio Frequencies
Cecily, an Australian Wikipedia user has asked on the Wikipedia help mailing list.
I am buying a uhf radio to use to communicate while skiing. Can you tell me if I am able to use a pair of uhf radios bought in australia overseas. I am particularly interested to know if I can use them in Poland.
Also what about Canada and the USA. I believe they will work but is it illegal to use one that is on australian frequencies.
If you could help me with Poland I would be most grateful.
There are three zones for frequency allocations. In some regions those zones are divided across national borders. Generally, radios from one nation are only to be used there. An allocation in one nation for family talk UHF radios, could be used for Military communications elsewhere. Dominick(TALK)15:54, 3 December 2005 (UTC)[reply]
So if I want to listen to military communications all I need to do is find out in which country those frequencies are used for domestic purposes and buy a radio there? Well, I suppose that if I were bent on that it might be easier to modify a radio to receive those frequencies. So the military won't be so stupid to use radio communication for 'classified' information. (Then again, ....) DirkvdM09:59, 4 December 2005 (UTC)[reply]
Salivary amalase?
Hello everyone! I am not sure if I recall this correctly, but I remember there is an enzyme in human saliva which helps with digesting glucose. The question I have is, if the time between chewing and swallowing is relatively short, what is the advantage of the body producing an enzyme which would only perform what seems to be a very very small part of digestion? --HappyCamper03:35, 3 December 2005 (UTC)[reply]
Salivary amylase begins the digestion of starch to glucose. Even a small amount of glucose will begin to trigger insulin release so that the insulin is rising as food is being digested. Salivary amylase is not necessary to digest starch but it helps amplify the speed of metabolic response, as well as providing a small burst of glucose as you begin to eat. Finally, conversion of even a small amount of starch to glucose in the mouth enhances the taste of carbohydrates in our mouths. alteripse03:51, 3 December 2005 (UTC)[reply]
Oh, I see...this sounds quite interesting...I didn't know that insulin is so sensitive to this. Would this be a reasonable example of a positive feedback system then? (From a controls perspective, "useful" positive feedback systems are almost unheard of, so it is excellent if this is considered one!) --HappyCamper03:54, 3 December 2005 (UTC)[reply]
I don't think salivary amylase is an example of positive feedback—where did you see the loop? Another biological example of positive feedback is during the menstrual cycle, such as the LH surge. — Knowledge Seekerদ04:22, 3 December 2005 (UTC)[reply]
As I understand it, the contribution of salivary α-amylase (ptyalin) to overall starch hydrolysis is a relatively small fraction of overall carbyhydrate digestion; the lion's share of this task is performed by pancreatic amylase. Salivary amylase is rapidly inactivated by stomach acid, so its action is very brief. (By the way, the product of the action of salivary amylase on starch is maltose (a disaccharide), which would not be expected to directly stimulate insulin secretion). Salivary amylase is thought to take on a more important role in infancy, prior to the maturation of pancreatic exocrine function. It may also assume a bigger role in the adult in cases where pancreatic exocrine function is compromised. For a scholarly dissertation on the role of saliva in digestion, see: Saliva and gastrointestinal functions of taste, mastication, swallowing and digestion -- Mark Bornfeld DDS dentaltwins.com Brooklyn, NY 05:30, 3 December 2005 (UTC)
I wouldn't characterize the insulin effect as positive feedback, but as early triggering or amplification of effect. Most food starch has a glycemic index almost as fast as glucose, indicating that hydrolysis of starch does not ordinarily contribute much to the time of absorption of many carbohydrates. There are a number of physiologic responses to the onset of eating that do not depend on waiting until substantial amounts of nutrients are already digested and absorbed and I suspect that the generation of a little glucose in the first minute of eating carbohydrates enhances some of metabolic and digestive responses as well as providing positive taste feedback to us. alteripse12:54, 3 December 2005 (UTC)[reply]
Atoms.
Hey, this is a bit of a hard question, and I looked but couldn't find what I was looking for. What are the chemical compounds/atomical mass/ect. of Blood, Bone, Skin, and Nail? Any help would be just wonderful, thank you.
~Ryan.
The chemical composition by element has been available for decades and is easy to find: [11]. The atomic masses of the elements you can easily look up. There is no list of all the molecules comprising blood, blone, skin, and nail because new ones are being continually discovered and it would run to the thousands. Of the four tissues you mentioned, nails are the simplest and are comprised mainly of a protein called keratin and water molecules but even the nails contain small amounts of many other things. As far as skin goes, you might just as well ask for a listing of every molecule in a human body. alteripse12:36, 3 December 2005 (UTC)[reply]
Nanobiotechnology
I have checked out the defination of nanobiotchnology from wikipedia, but I do not understand what it is saying. Can anyone please tell/explain to me what nanobiotechnology is really?
For example the use of tiny biosensors that can be implanted under the skin and monitor things like blood glucose level. These use an enzyme to break down the glucose, a biological recognition layer to record the amounts of the products of the enzyme-substrate interaction, and a transducer to convert this into an electrical signal - very clever really! --Unregistered user 18:07 3 December 2005
I am not sure that I understand the extent of this process, digitizing library collections. Is it simply creating a digital catalog, or the larger process of scanning documents and entering data?
Thanks so much for clarification.
Usually, it's scanning entire books. (I'm assuming you're referring to projects such as Google Book Search.) Some library whose name I can't remember in Egypt which has a large collection of rare Islamic texts recently scanned its entire collection. --YixilTesiphon15:37, 3 December 2005 (UTC)[reply]
how long did people need totrain with weights to lower their risk of coronary heart disease by 23%?
The question is like above. I searched but they couldnt find anything. So here goes, how long did people need totrain with weights to lower their risk of coronary heart disease by 23%? A) 30 minutes b)55 mins c)80 minutes
Second one,
After what age would people startlosing muscle mass & strength caused by hormonal changes? A)30 b)40 c)50
I need it to be very accurate. BTW, thanks to everyone who helps me with the question. Many thanks ppl.
The precision of the desired answer tells me the answer was produced by a specific research study which you were supposed to read. How do you expect us to know which study that was? alteripse18:25, 3 December 2005 (UTC)[reply]
I was trying to run the 5.10 live cd on my older PIII 800 Mhz 128MB RAM Dell Inspiron 2500, but it is glacially slow. I'm assuming it's because 128MB is not enough to run with all the default software the live cd has on it, but it's so slow (10min to open a terminal window) that I can't even kill processes to free up memory. Is there an easy way to get the 5.10 live cd to use a file on the windows partition as swap? Or do I just have to wait till I get a terminal window and set up a swapfile manually? (Which I'll have to go search to remind myself how to do that again.) Thanks - TaxmanTalk15:53, 3 December 2005 (UTC)[reply]
If you are using windows xp, your windows partition is probably a [NTFS] partition, which ubuntu/linux cannot write to, only read it. If you have a fat32 partition, I don't know, it might be possible. --WS01:35, 5 December 2005 (UTC)[reply]
XP on a machine of those specs? Surely you jest. No it was ME, but I decided to just bite the bullet and install, and it worked out all for the better. Everything works amazingly well including the sound, power management, and wireless. I'm assuming the winmodem won't but oh well. It's still slow, so I'm planning to figure out how to slim it down a lot. I guess the first step would be a lighter window manager. I'll try to haunt some Ubuntu forums and learn the ropes, but if anyone has some info on good ways to slim down the ram requirements, I'd be interested. - TaxmanTalk14:23, 5 December 2005 (UTC)[reply]
It's difficult to configure Linux distros on Live CDs to access the hard disk for its swap files. Alternatively, you could use Damn Small Linux, which is only 50 MB in total, but fits a GUI and a surprising number of programs onto it. Surely 50 MB can fit into 128 MB of RAM. :) -- Daverocks11:25, 5 December 2005 (UTC)[reply]
Well I had an older DSL disk, but I couldn't get it to boot properly, the 2.4 kernel would hang at some point. And with the compression those livecd's use 50 MB could be made to overwhelm 128MB of RAM too :) - TaxmanTalk14:23, 5 December 2005 (UTC)[reply]
climate change/global warming
what is the difference between global warming and climate change? why did the media, which used to call it global warming, suddenly all start calling it climate change in unison? who made them change? — Preceding unsigned comment added by Zzzzz (talk • contribs)
Have a look at Global warming and Climate change; basically climate change describes the broader phenomenon which includes not only the current anthropgenic warming but other fluctuations such as past glaciation, etc. In addition, while warming is the major phenomenon, other things like altered rainfall regimes are also part of the picture. Guettarda16:14, 3 December 2005 (UTC)[reply]
I'd say that last bit is probably the most important. Global warming is just one aspect and it's arguably not even the worst. And to a layman (especially one living in a moderate or cold climate) it might even sound like a good thing. Also, warming is the most likely effect. Other theories say we could be creating a new ice age. So calling it warming is a premature conlusion. That there will be a (major) climate change is however beyond doubt by now. Finally, with global warming you may still get local cooling. DirkvdM10:07, 4 December 2005 (UTC)[reply]
astronauts
Could kindlygive the list of astronuts with their nationality, date and year who have landed on moon till 2005
As future-proofing, it hardly seems urgent. But that doesn't make it political either; I think we all agree that the list would include women if there were any, so the astronauts' sex is not relevant to their inclusion and doesn't need to be mentioned in the title. --Trovatore22:57, 3 December 2005 (UTC)[reply]
The article includes the 12 Apollo astronauts who went near the moon but did not land as well as the 12 who did land, so in any case the "walked on the moon" part would be wrong. --Anon, 07:52 UTC, December 4, 2005
Nunh-huh is probably talking about this article. A little hard to find, because the link he gave was capitalized differently. It wasn't actually moved; it was redirected as a duplicate article. --Trovatore08:00, 4 December 2005 (UTC)[reply]
photon mass
No one's responded to this question on Talk:Photon, so I thought I'd ask here.
What is the status of the possibility that photons have nonzero rest mass? I remember seeing an old Scientific American article on it, showing how Maxwell's equations would have to change, among other things. As I understand it, current observations have put an upper bound on photon rest mass, but have not ruled out its existence. However, supposedly (I don't understand why), the discovery of a magnetic monopole would refute a nonzero rest mass for photons.
Anyone know anything about this? Have there been any theoretical or experimental developments that bear on the question since the article I remember (which probably would have been from the '70s or so)? --Trovatore19:37, 3 December 2005 (UTC)[reply]
It is impossible, in some sense, to rule out the photon mass. But there are upper limits, set by experiments where we'd see the changes to Maxwell's equations if it had a mass above some value. At current, the recognized upper bound on the photon mass is
Or about 0.0000000000000000001 times the mass of the electron, the lightest particle whose mass is known. I don't know anything about magnetic monopoles ruling out photon masses, but it is the sort of strange thing that finding magnetic monopoles would do—they also explain charge quantization, which I saw a proof of once but have since forgotten. Well, that's a start at least. -- SCZenz19:46, 3 December 2005 (UTC)[reply]
Thanks. Might make an interesting note in Photon. --Trovatore 20:00, 3 December 2005 (UTC
Anyway, particle physicists don't refer to "photon mass" in this manner, since by E=mc² it would be completely redundant with the energy. Photons that are internal lines in Feynman diagrams can have non-zero mass (which can't be directly observed), but this is completely different. -- SCZenz23:29, 3 December 2005 (UTC)[reply]
I don't think a monopole would refute a nonzero mass of the photon. It would probably depend on what kind of mass it was. For example, if the photon mass were due to a Higgs mechanism, monopoles would still be allowed. As for whether monopoles are allowed in the Proca equation, or if the mass is from a topological term, I'm not sure. -lethetalk23:22, 3 December 2005 (UTC)[reply]
Running Processes
I run Windows XP, and I always have a lot of processes running. Right now, for example, I have 54, and I think that's low for today. Some I recognize (such as firefox.exe, or WINWORD.exe), but others I do not. Is there a program I can get, or a website to which I could refer, that would help me eliminate some of the extra ones I'm sure I'm running? Thanks! --ParkerHiggins20:26, 3 December 2005 (UTC)[reply]
Just copy the process name into Google. You will quickly find many sites discussing each process. Windows XP has MANY programs that run in the background. It isn't like Windows 98 where you could safely kill everything except systray and explorer. As you find out what is running, you may find services running you don't want (like wireless network detector, pcmcia monitor, or firewire support). You can disable those services in the control panel somewhere. I don't remember exactly where. I gave up on Windows a couple years ago. --Kainaw(talk)02:09, 4 December 2005 (UTC)[reply]
One place is in Control Panel > Administrative Tools > Services. In the right hand pane will be a list of services, their names, a long description, and whether they're started or not. George03:32, 4 December 2005 (UTC)[reply]
To turn off running processes, go to "Run..." in the start menu. Then type in "msconfig". This should bring up a window titled "System Configuration Utility". Click on the "Startup" tab. There should be a list of processes there that you can check or uncheck to startup with windows. Hope that helps!--Dimblethum05:12, 4 December 2005 (UTC)[reply]
DVD X
The Wikipedia Help mailing list received an inquiry from a reader as follows.
I bought DVD X copy program the last day they could sell them at Best Buy and when I went to activate it they said it was not longer allowed to activate the programs so I was out $119.00 and left with a program that I could not use I would really like to know if there is anything that I can do I guess this is what happens when you are computer stupid. My license ID:2641969 and I also have a pass word for it but need an activation key for it
From the DVD X website... "CAUTION: Authentic DVD X Copy software is no longer being sold anywhere. Many "closeout", clearance, auction and discount websites are selling fake DVD X Copy Software products and "patches" that are not authentic, CANNOT be activated or are cracked versions that DO NOT WORK properly and/or that contain spyware. Beware of any sites that continue to sell version 4.0.3.8 and that guarantee activation. DVD X Copy products purchased from these sites are not authentic, not eligible for support or updates and should be returned for a refund." --Kainaw(talk)02:05, 4 December 2005 (UTC)[reply]
HFS command line utilities
I can't remember what are the command line utilities for changing the locked status of files under Mac OS X on an HFS plus volume. -lethetalk23:04, 3 December 2005 (UTC)[reply]
When a penguin swims vs. walks, they have different heart rates due to a different intake of oxygen.
When it swims, it needs more oxygen right?
Is there any new information(from the past 3 years) on this topic, so i can base my essay on that?
Thanks alot
Your assumption is most likely incorrect. While I am not a penguin expert, semi-aquatic animals have a slower heartrate in water than on land. A quick google search confirms the same for penguins [13]. The issue is oxygen use. Penguins don't want to consume more oxygen while swimming - they want to consume less. So, over time, penguins who have slower heartrates while swimming are able to swim longer and deeper and get more fish. --Kainaw(talk)02:03, 4 December 2005 (UTC)[reply]
I was only assuming that penguins would have a similar reflex to mammals. As for the avian diving reflex, according to Ponganis (I don't know who he is), many avian species have diving aerobic activity that exceeds the calculated diving aerobic limit - requiring a slowed use of oxygen during diving. [14] --Kainaw(talk)04:20, 4 December 2005 (UTC)[reply]
One comsideration. You probably mean oxygen consumption in time. But a swimming penguin is of course much faster than a walking one (what, twenty times faster or so? - 1 km/h vs 20 km/h). So the consumption per distance (ie the efficiency) will be much higher when swimming. DirkvdM10:21, 4 December 2005 (UTC)[reply]
One of your problems is that you haven't justified your assumption that penguins need more oxygen while swimming than while walking/waddling: if I were forced to walk like a penguin, then allowed to swim naturally, I think I would find the latter less tiring... Another, more complex point is to look at thermal regulation in penguins: in which environment is their overall heat loss the greatest? Finally, if you're still stuck, consider the oxygen equilibrium in large aquatic mammals (e.g., whales): this won't give you the answer, but it will at least convince you that the answer is out there somewhere! Physchim62(talk)13:15, 4 December 2005 (UTC)[reply]
Wiki administration
The Wikimedia help desk received the following question from Carey, a Wiki administrator.
I am wanting to do a little administration on the Wiki I installed internally but I didn't see anything concerning my idea. I want to limit a specific user or group to only be able to edit specific pages and their contents. Basically this user is going to be updating one specific page but I don't want that user to be able to edit any other pages.
I know there is a protect option to protect pages but my current Wiki has several thousand pages and protecting each one would be very time consuming not to mention not a suitable solution. If anyone knows of a way or if this isn't possible, I would like to know. Thanks in advance!
Can you guys help me find a good and reliable databases that features 2 dimensional molecular structures? An example of a 2 dimensional structure would be the image in the AMP article. I've found some databases on 3-dimensional structures of proteins [15], but am having a harder time finding something similar for 2 dimensional structures. KBi03:31, 4 December 2005 (UTC)[reply]
The Linstrom, Peter J.; Mallard, William G. (eds.); NIST Chemistry WebBook, NIST Standard Reference Database Number 69, National Institute of Standards and Technology, Gaithersburg (MD) will probably not always have the structure you're looking for, but it is not bad. Otherwise there is ChemFinder, or PubMed, or several others depending on the compound you're looking for (Google as a last resort, but it can be useful for this type of problem)... A little bit more details about the type of compounds you're interested in would help to answer your question more specifically. Physchim62(talk)13:23, 4 December 2005 (UTC)[reply]
To calculate Heat dissipation
Could you please forward the formulae, which will be used to calculate Heat dissipation?
For example, if a equipment power consumption is 200 watts, how much will be heat dissipation value from that equipment? How to calculate?
I suggest getting an engineering textbook. For example, Coulson & Richardson's Chemical Engineering, Volume 1: Fluid flow, Heat transfer and Mass transfer. There is no simple formula, except for heat transfer through radiation (Stefan-Boltzmann law). For non-radiative heat transfer (convection), you've get a lot more work to do. And the subject can't really be covered properly in anything smaller than a book. (And there are quite a few available) --BluePlatypus23:52, 4 December 2005 (UTC)[reply]
If the system consumes 200W in power, unless it comes out in another form, almost all of it is heat. If a mythical board in a 10V system draws 20A, and has an output that sends a signal with 200Vrms and 1A almost no heat would be converted. ALmost all computers make heat from all the power they consume. Now a 200W powersupply does not always generate 200W, but has a maximum rating of 200W.Dominick(TALK)15:51, 6 December 2005 (UTC)[reply]
Optics of reading a CD
I've been looking for information on how a CD is produced and read. In particular I am interested in the optics involved in reading the CD. Can anyone refer me to a source that discusses exactly what the interference is that reduces the light reflected at a pit-land boundary? Is it reflections from the two surfaces on either side of the boundary?
The article at http://en.wikipedia.org/wiki/Compact_disc contains a wealth of information, but there is one portion that bothers me. In the 4th paragraph under "Physical details" it is stated that the 125 nm pit depth is about one-sixth of 780 nm wavelength of the laser, and then "The sixth, 125 nm, (and not a quarter) of the wavelength was chosen to have a good trade-off between the push-pull radial tracking signal and the full-aperture read-out signal."
The relevant wavelength has to be that in the bottom polycarbonate layer. The pit depth would be one-fourth of the wavelength in the material for a refractive index of 1.56, close to what I find (1.55 to 1.58) listed in various places, so this is consistent. This raises a question about the rest of that sentance regarding tracking. I am seeking info on the subjest, and am not comfortable editing the article at this time. Apologies if I've violated any protocals here. --StanH06:22, 4 December 2005 (UTC)[reply]
You're right. That change (from one quarter to one sixth) was made by user Dsc a short while ago. It appears to be purely wrong, perhaps he doesn't understand how wavelength is reduced in a medium, and assumed a reason for it. The rest of the info would seem to be suspect. --Bob Mellish06:39, 4 December 2005 (UTC)[reply]
what is SIP Protocol
Dear Sir,
Could you plz let me know the meaning of the sentence"Voice Gateway on SIP Protocoland and all are line port"?
My question...........
1)what is SIP Protocol?How it works?How it is related with Voice Gateway?
2)What is Line Port?
On the back of your Voice over IP equipment, there should be two ports: LINE and PHONE. The line port should be connected to the phone line, and if you have a phone handset, that can be connected to the phone port.
Lol, interesting question. Usually it is white, but, from what I've heard, it can be yellowish, grayish, or brownish and still be fine.Dimblethum04:46, 6 December 2005 (UTC)[reply]
The answer to point 3 is suggested by this UN report: "photosynthetic energy capture is estimated to be ten times that of global annual energy consumption". The latter was 3.8×1015BTU in 1999 according to US DOE EIA. The UN report also calculates the efficiency of photosynthesis to be between 3% and 6%. --Heron21:35, 4 December 2005 (UTC)[reply]
Photosynthesis is not the only variable that is under the influence of living organisms. The composition of the atmosphere can be altered by living organisms, changing the ratio of energy entering and leaving the biosphere. --JWSchmidt02:53, 5 December 2005 (UTC)[reply]
Yes; very generally, I'm curious whether the relatively small amount of energy available to the biosphere is enough to control global energy variations to a significant degree. I suppose altering Earth's chemistry is probably the easiest method. ‣ᓛᖁ♀ᑐ04:27, 5 December 2005 (UTC)[reply]
Hot water freezes faster than cold?
I was watching a tv programme recently that performed an experiment where room temperature and near boiling water was placed in different ice cube trays, when placed in a freezer, x minutes later the hot water had frozen faster than the cold water. I've yet to try this so don't know if this is true, but if it is, why would this be the case? I can't think of any logical reason why this would happen, so i'm wondering if anyone else knows why? Thanks in advance 84.64.138.23422:00, 4 December 2005 (UTC)[reply]
I've made a table in my LaTeX document that's narrower than the page, but wider than the page margins. LaTeX keeps aligning it with the left margin instead of centering it horizontally on the page. How can I get the table centered horizontally? I'm using the "tabular" environment at the moment. Thanks. -- Creidieki23:49, 4 December 2005 (UTC)[reply]
Have you tried resizing the table to the margin size or less?
Dear Help Desk
There is a new construction tunneling method is called New Austrian Tunneling method which we have read it from your website we are going to do a research program on this subject. This method is based on using a single lining of sprayed concrete using HPP fibres. Could you please advise me if there is some paper published about this method and how we can reach to any projects details using this method.
With Best regard
Dr Hamid Abbasi (FRPRC)
Check the "Internal links" section of the article you're referring to. If there's nothing there, click on the "history" tab above the article, and scroll down to the creator of the article. Click on his/her name, then click on the "talk" tab above his userpage, then click on the "+" tab to leave him/her a message. --YixilTesiphonSay helloConsider my Wikiproject idea22:26, 5 December 2005 (UTC)[reply]
Do bluetooth phones have SAR ratings?
Bluetooth techology sounds like a good way to increase distance between my head and the phone thereby making them safer choices.
Questions...
What type of "waves" do the ear pieces give off?
Is there a SAR for these waves, like there are for Dig/Analog phones
What is considered an acceptable (i.e., safe) level of emission?
Is bluetooth any safer than regular dig/analog cell phones from a emission stand point?
A flint is composed of mischmetal, iron oxide and magnesium oxide. However, why is German flint much better than the Chinese flint? What are the differences? Does the purity of mischmetal make the difference? Or, the process of making the flint matters? Please kindly answer my questions, or kindly provide any references to me. Thank you very much.
In a standard 9-5 work environment, what is the annual cost in wasted energy of leaving a PC monitor switched on overnight and at weekends, if the PC itself is switched off at those times (so the monitor will be in standby mode, not displaying anything)? Assume a fairly standard 15" CRT monitor, and UK energy prices. I'm trying to convince my work colleagues that this is worth bothering with (I work for a charity and saving money is important), but they all think that the cost is utterly negligible. I've tried Googling but couldn't find anything that quantified it in hard cash, though others may have more luck with different searches. --194.73.130.13216:19, 5 December 2005 (UTC)[reply]
A search for "monitor power consumption" comes up with useful information. For example, this 15" IBM monitor eats 70 watts when its in regular use, and 10 watts in standby -- and 5 watts in "VESA off", which I imagine is how things would be with the computer turned all the way off. Using this UK power cost calculator: assume, then, 128 hours standby per week, ~512 hours standby per month will run you £0.14 -- about the equivalent of leaving a 100-watt lightbulb on for a day. Wasting any energy, of course, is not a good thing, but you won't be able to make a hard cash argument for it. --jpgordon∇∆∇∆16:39, 5 December 2005 (UTC)[reply]
And it seems to vary by monitor make/model/age; my Optiquest Q71 (a 17" CRT) claims less that 3 W consumption in standby/powersaving mode. The Energystar specs may prove helpful. --Bob Mellish18:47, 5 December 2005 (UTC)[reply]
We have several posters at work that say that leaving a [CRT] monitor on overnight wastes enough energy to laser print 800 A4 pages. How accurate this is (or indeed how much energy it acutally is) I don't know, but I would suspect it is a useful rule of thumb. Thryduulf01:51, 6 December 2005 (UTC)[reply]
I would expect a printer running for that long to use a lot more energy than a CRT monitor left on at night, but that might just be reflection of my ignorance. -04:27, 6 December 2005 (UTC)
5 Watt over 1 year is 5 x 24 x 365 = roughly 40 kWh. A 200 horsepower car engine delivers 147 kW. So the yearly power consumption of one monitor would let a car engine run for less than 20 minutes (is this correct?). Convincing one colleague who lives nearby, but commutes by car, to go to work by bicycle (or a more distant one by public transport) just one day per year would have a similar, if not bigger, effect. The goodie bit about this is that you can do it yourself (providing you don't already), so you don't need to convince anyone. And you could even do it every day. Wow, think of the effect that would have! And then you could also try to convince your colleagues to follow that example. In other words, consider barking up the right tree :) .
I would love to commute by public transport, but 2-3 hours on three busses with a 5-10 minute walk each end vs 50 mins-1 hour door to door by car is no contest unfortunately. Thryduulf11:49, 6 December 2005 (UTC)[reply]
Which makes me think. Shouldn't we have an article that lists the power consumption of different household items and such (and the power cost of making them). I bet the car would be at the top of the list in a very isolated position. I've searched for 'power consumption', which didn't give any results. And ecological footprint doesn't help either. DirkvdM11:29, 6 December 2005 (UTC)[reply]
The virus article states that vaccination is "the process of administering live, albeit weakened, microbes", though it also states that the cowpox virus is "a relatively benign virus that, in its weakened form, provides a degree of immunity to smallpox"
Firstly, obviously these sentences seem to contadict eachother. Is the virus weakened, or are the microbes containing them?
In the context of the source article, the term "microbe" refers to the microscopic causative disease agent-- in this case, the virus. It does not refer to some host organism (although there are bacteria, which are microbes, that are parasitized by viruses, which are also microbes). Smallpox vaccine is actually live vaccinia, or cowpox virus, and is not an attenuated virus. It is, however, sufficiently antigenically similar to smallpox that a cowpox infection (the intent of administering the vaccine) will confer protective immunity in a person who is immunologically competent. There are (other) vaccines that are live attenuated virus vaccines, such as the Sabin polio or the FluMist influenza vaccines, in which the virus is alive but modified so that it does not cause a full clinical infection.
Viruses are sometimes attenuated by culturing them in an environment that is different from the that found in the intended recipient of the vaccine. For example, a virus is cultured in a progressively colder environment, which selectively favors successive generations of the virus that are adapted to an environment that is below body temperature. These viruses would presumably find normal physiologic body temperature to be inhospitable, but would survive long enough to cause a mild infection and provoke an immune response. Denaturation of viruses usually results in a killed virus vaccine. -- Mark Bornfeld DDS dentaltwins.com Brooklyn, NY 18:04, 5 December 2005 (UTC)
Is there such a bird in china as the Xu? I find mention of it in two articles by the same anonymous user (nullaby and orange flavor chicken) and I can't decide if he or she is just making it up. I've googled it as thoroughly as I can and find no mention of it, and while I know that isn't a substitute for actual research, it usually turns up something. So if there are any naturalists or bird afficionados out there I'd appreciate some information.
thnx. Jasongetsdown18:37, 5 December 2005 (UTC)[reply]
I'm not sure what bird the person was referring to. They mention the loon, which is lan ren in Chinese. Then, nightingale is mentioned, which is ye ying in Chinese. The first thing that comes to mind is the use of xu for fake. As such, xuguo means to make something up and xuwei means false. But, another use of xu is to indicate an animal is domesticated. But, it is commonly pronounced chu when used that way (the proper pronunciation is xu, but because it is often followed by sheng, it becomes hard to say xusheng). Finally, there is a surname Xu. Since the person capitalized Xu every time it was used, perhaps the family Xu has a special bird named after them. All in all, there is no bird named Xu in my dictionary. --Kainaw(talk)01:00, 6 December 2005 (UTC)[reply]
Why are old things buried?
What is the mechanism by which all things get buried with time? Is it always slowly raining soil out of the sky? it seems that the older a thing is, the deeper it is buried. Why is this so?
It is not the case that old things are always buried. Some things are pushed to the surface over time. For example, I live on an old plantation where multiple civil war battles were fought. When I work in the yard, I still find old things being pushed up to the surface after every rain. I'm sure some things are pushed down as well. --Kainaw(talk)20:36, 5 December 2005 (UTC)[reply]
I don't think Civil War-era artifacts are "old" in the context of the question. But sure, buried things sometimes get unburied. Then they usually don't last very long. I think that's part of the answer to the question: Things get either buried or destroyed, and we don't find the destroyed ones.
But no, it's not about "soil raining from the sky", mainly. Successive layers of sediment are generally added by water—either at the bottom of a body of water (since perhaps disappeared), or by flooding of rivers in an alluvial plain. Lots of different things can happen after that. With luck, maybe a geologist will come along and explain more specifically. --Trovatore20:50, 5 December 2005 (UTC)[reply]
Gravity tends to push things downward, especially if they are relatively dense and the soil is moist, but more generally things tend to get buried as material accumulates on top of them. Dead leaves, soil that gets moved around, dust. Things tend to be exposed by erosion, but what erodes somewhere has to deposit somewhere else. Plant roots can bury something (imagine a tree growing up on top of an object) or expose them (imagine the tree falling over and the roots tearing the object out of the ground). Then add the magic factor of time... Guettarda20:50, 5 December 2005 (UTC)[reply]
Erosion is the mechanism where broken down rock or soil moves around the place. Where I live, the local "hills" are weathering and eroding (ie moving) down towards the city. I guess in a long time the city will get buried. Basically the weathered rock, sediment, can be pushed around by wind or water (if you are under the ocean or a river) and will bury stuff. --Commander Keane20:54, 5 December 2005 (UTC)[reply]
"Is it always slowly raining soil out of the sky?" It a way, yes. Plants take carbon dioxide from the atmosphere and use the carbon in it to make their bodies (wood, leaves, etc). When a plant dies it falls to the ground where it rots. The action of the rotting returns quite a lot of that carbon back to the atmosphere (as carbon dioxide again). But some gets buried by more dead plant material (leaf litter and stuff) before it has had a chance to fully decay. Buried, there's little oxygen; it keeps decaying, but without oxygen the bacteria that decay it can only work very slowly, and they never manage to finish the job. Over the years and centuries new plants grow and die and partially decay, and each summer adds another thin layer of material, piling up on what's underneath. So eventually things that once were on the surface are covered by metres of material. Peat is formed this way, and is often many meters thick. A similar process happens in the sea, with little plants and animals that live in the photic zone (near the surface, where there's lots of light) dying on the surface; their little bodies rain down on the sea floor (that's marine snow) and it piles up, year after year. Sometimes this piles up for tens of millions of years, and eventually becomes chalk. -- Finlay McWalter | Talk
Which still leaves the question where the material comes from (the net result). I suppose part of it is the trees with deep roots that 'suck up' material from the ground and then dying, falling and depositing it on the ground (as Finlay pointed out), effectively turning the ground upside down. By the way, I believe Darwin investigated this too (measuring accumulation in his back yard), but I don't remember what he found. I vaguely remember it was something to do with snails. DirkvdM12:40, 6 December 2005 (UTC)[reply]
A little-known aspect of this is that the attraction between an oil molecule and a water molecule is actually stronger than the attraction between two oil molecules. The reason they don't mix is because the attraction between two water molecules is much stronger than either of those (because of hydrogen bonds). It's like the water molecules form a clique and although the oil molecules want to join, they can't because the water molecules don't think they're cool enough. (Silly little metaphor, but it helps. =P) ——Keenan Pepper22:06, 5 December 2005 (UTC)[reply]
Maybe because removing the gases affects pressure, and would affect the self-ionization of water, or something. Do hydronium and hydroxide ions play a part in the solution formation? I would imagine. Of course this is only a wild guess. -- Natalinasmpf22:46, 5 December 2005 (UTC)[reply]
The mixing should not be any surprise...in an oil and water mixture, there is always a slight amount of one substance dissolved in another - it just might not be an appreciable amount. --HappyCamper01:18, 6 December 2005 (UTC)[reply]
It was complete, like salt and water.
December 6
Petroleum jelly
Why isn't petroleum jelly harmful for human use?
Everything is harmful to humans in excess. You can overdose on water and oxygen. Petroleum jelly has a long history of providing health benefits. It has also been consumed in small quantities by some who believe it is good for the digestive system. If taken in excess, it is harmful. --Kainaw(talk)00:32, 6 December 2005 (UTC)[reply]
Are you asking why it might contain polysaccharides and monosaccharides? If so, then here is my answer. Sugars are usually stored as polysaccharides (why that is, I'm not exactly sure); glycogen is the main storage form in animals, and cellulose is for plants. To be used for an energy source the polysaccharide has to be broken down into a monosaccharide (usually glucose). So when a cellulose molecule in a plant is broken down, you could have both polysaccharides and monosaccharides at the same time.Dimblethum05:02, 6 December 2005 (UTC)[reply]
What's up with these errors?? I have no idea why i'M getting them, AOL has always installed just fine in the past (AOL spyware not withstanding), and now everytime I start the process I get these..
As an alternative, would anyone know where I can find a much older aol installation? online? something like AOL 5.0 or 6.0, so I don't have to put up with all the addweary goodness that is 9.0b-SE--Aolanonawanabe23:49, 29 November 2005 (UTC)[reply]
Well, I can't help with the error message, but there appears to be an AOL 5.0 version for download at this site. I've never used it before, but it looks to be fairly legitimate. --ParkerHiggins01:06, 30 November 2005 (UTC)[reply]
Well, a quick google determined that "AOL 5.0 has resident broadband support capability" (from this site with the annoying pop-up). I think that means you're a go, but I can't be sure. You can check on the article, if you're in doubt. --ParkerHiggins01:27, 30 November 2005 (UTC)[reply]
Windows is a very broken thing hobbled by having to be backward compatible and a certain amount of poor design and failure to iron bugs out, so I'm surprised you would even ask why. On top of that, various installs and uninstalls of other software could easily leave your system in a broken state, that could interfere with the current install. The only solution to some windows failures is a clean install, but people will tell you that can be very risky as the distributor that installed in the first place had worked out all the driver issues etc, and probably had an image they ghosted onto the drive. You don't have that, so the reinstall could be risky. That said, I've used the OS reinstall disks that come with dells several times and they general work pretty well. So I'd say backup backup, get all your application install cd's and have a clean go at it. - TaxmanTalk13:59, 6 December 2005 (UTC)[reply]
Medical/psych question
Hey, this probably isn't the right place to ask this, but I have a question re mental health,fulfillment, and psychiatric meds.
I've got a great psychiatrist. He brought me back from a really bad place. I'm taking four different meds every day to keep things in the old brain operating normally, and as long as I do so I am able to deal with my feelings that life is utterly meaningless and lagerly devoid of pleasure and happiness.
That's what the meds are supposed to do - allow me to handle my feelings. Here's the thing - I'd like to enjoy life and be happy sometimes, not just not be overcome. I'm currently in therapy, and practicing cognitive behavior therapy. It is interesting but not efective in making me happy.
Is there any medicine that makes you happy? I have a _large_ family to support, and would rather not just exist as the food, shelter, and cash producing machine. I'd really like it if I could enjoy life as well.
I wouldn't say there was. Besides, medicines that make you "feel" happy IMO would be kind of an empty, meaningless happiness....I am reminded of the "happiness" induced in Huxley's "Brave New World". Medication to relieve depression is one thing, but to seek happiness I would indulge in philosophy, metaphysics and Nicomachean Ethics, not medication. -- Natalinasmpf04:51, 6 December 2005 (UTC)[reply]
I think there's a middle ground in there. I agree with Natalinasmpf that there are no psychiatric medications that make you happy, nor would you likely want them if there were. At the same time, many people, myself included, have better experiences with meds than something that merely allows you to function while still having depressive feelings. It's a fine line to draw, I know, but my experience is that the medicine didn't make me happy, it allowed me to be happy. On medication, I wasn't some unnaturally cheery person who was always happy regardless of the circumstances; but I was happy some of the time, more or less when you would expect a normal person to be, whereas when I had been depressed and not on any medication, I was constantly sad, even when I had no reason to be. If that's something you want to explore with your psychiatrist, talk to him/her about either increasing your dosage or switching medications. The danger is that the reaction to psychiatric medications varies greatly from person to person--what works wonders for one person is completely ineffective for another, and vice versa--and the only way of knowing what works best for you is experimentation. So if you do try switching medications, the danger is that you may give up even the functionality you've achieved so far. Whether that's a risk you're willing to take is between you and your psychiatrist. 12.223.56.10609:26, 6 December 2005 (UTC)[reply]
Taking medication that makes you feel happy is just kidding yourself. Perhaps if the therapy works your psych will decide to lower the dosage somewhat. Still, the best way to feel happy is to do stuff you like to do with friends and family. - Mgm|(talk)11:20, 6 December 2005 (UTC)[reply]
Prolog
Is it possible to implement an equality check for "arrays" in Prolog? I am running into a problem where my particular version of Prolog is comparing memory addresses instead of the actual array contents in the recursive check. Any tips? --HappyCamper03:11, 6 December 2005 (UTC)[reply]
If you're using "A == B" (A identical to B) you might try "A ?= B" (A unifiable to B). If you're actually using lists, and they're fully instantiated (no uninstantiated elements), "A ?= B" should tell you whether the lists contain the same elements (recursively, all the way down to atoms) in a single expression. -- Rick Block (talk) 03:24, 6 December 2005 (UTC)[reply]
Active polymer material which acts as an antiback agent in textile washing industry
Will pressure different inside and outside a building?
Will the air pressure different inside and outside a building?For a building near the sea,will the air pressure different too?
For the most part, no, there will be no difference. Buildings are not airtight, and even if they were, the pressure would rapidly equalize as soon as anyone opened a door. One exception to the general rule would be inflatable domed sports stadiums, such as the RCA Dome, where a roof of flexible fabric is held up by air pressuree. In these, the pressure is retained while people enter and exit via revolving doors. There are also conventional doors which can be used as emergency exits, but the pressure difference does create a stiff breeze if these are opened. Chuck09:09, 6 December 2005 (UTC)[reply]
Skyscrapers also seem to have a stiff breeze when doors are open; perhaps they have trouble equalizing pressure because the external pressure is different between the top and bottom? -- SCZenz09:15, 6 December 2005 (UTC)[reply]
It shouldn't be because of the pressure difference between top and bottom, either externally or internally. The difference in pressure due to altitude is an effect of gravity, and it would have the same effect both inside and outside the building. (That is, the external pressure at the top of the building will be less than the external pressure at the bottom, but at the same time the internal pressure at the top will be less than the internal pressure at the bottom.) I'm just guessing here, but I suspect that skyscrapers, while not perfectly airtight, have few enough spaces for gas to escape that it is possible for a pressure differential to build up, just as a result of ventilation, possibly with effects due to heating or cooling the air inside the building too. Note that skyscrapers also generally don't have windows that can be opened, limiting the ways in which the external and internal pressures can equalize. Chuck09:32, 6 December 2005 (UTC)[reply]
No, tornado damage is caused by the wind. It was at one time thought that when a tornado was approaching, one should open a window to "equalize the pressure," it's now known that this is unneccessary, and in fact it is strongly recommended that one not open a window. See here and here for examples. Chuck13:46, 6 December 2005 (UTC)[reply]
All that says is that openning a window is pointless and would just scatter broken glass anywhere, it doesn't say anything about there not being a preasure difference, not to mention wind is a preasure difference--Aolanonawanabe15:43, 6 December 2005 (UTC)[reply]
Air flow, such as wind, causes pressure to drop (this principle is also used in wings). So if a wind starts blowing, there will be a difference in air pressure, causing air to flow out at a rate dependent on the size (and location?) of apertures. And when, after satbilising, the wind (suddenly) drops, there will again be a pressure difference. About the location of the apertures. Suppose they are all at the windward side. Then I suppose air will get blown in, causing air pressure inside to actually increase despite the decreased outside pressure. DirkvdM14:25, 6 December 2005 (UTC)[reply]
That is very correct. A house cannot adjust pressure immediately. Wind also creates lift on the roof. Combined, many roofs give way and blow down the road. --Kainaw(talk)16:57, 6 December 2005 (UTC)[reply]
Kerosene and burning it.
I have searched everywhere but was not able to find the answer I was looking for.
If I pour kerosene (ordinary kerosene) into a cup (a standard cup in which you drink tea) and then bring a lighted matchstick over it, will it burn? I am sure it will not, but my friends at work say it will and have bet me one cup of tea. I also remember doing this exact thing when I was a young kid and it did not.
Various web pages, such as this one, give the flash point of kerosene as 110° Fahrenheit (which is 43° Celsius) or somewhat higher. In order to start it burning you would have to warm some of the kerosene to at least that temperature. A match held very close to the liquid might very well do it: after all, people light kerosene lamps easily enough. But a match held "over" the cup at a short distance might not (even though a more dangerous fuel like gasoline would ignite). I would not want to speculate as to how close you bring it in safety. Indeed, I'd say "don't try this at home, kids." --Anonymous, oh my look at the time, 10:10 UTC, December 6, 2005
I think the vapour pressure of kerosene at room temperature in low enough that it is actually pretty hard to light. I have seen someone demonstrate this by dropping a lit match into a container of kero. The match went out. Kero lamps use presure or wicks to help vaporise the kerosene before burning it. --Martyman-(talk)11:03, 6 December 2005 (UTC)[reply]
Keep in mind that the liquid does not burn. The vapor/fumes/gasses burn. In a lanp, you light the wick, which heats the kerosene that has crept up the wick. At first, you are burning cotton (or something similar). As the heat builds up, you begin burning fuel instead. On a similar topic, I did an experiment with lighting a milk carton full of gas and one with just a little gas in the bottom. The full one caught on fire and made a mess. The empty one exploded and left a hole in the ground. Once again, the reason was that the fumes burn - not the liquid. So, going back to the original question, holding a match over the liquid to try and get it to start evaporating should get a flame started, assuming the match doesn't burn your fingers first. --Kainaw(talk)16:52, 6 December 2005 (UTC)[reply]
"How can i make women attracted to me"?
If you want the slimy method of doing so, do a Google search for "seduction" and there's all manner of people who are prepared to sell you all sorts of grooming, conversational, and body-language tricks that are supposed to help seduce women. The proprietors swear by them; independent endorsements are a little harder to find. If you want a little chemical help of the legal and ethical kind, there are other people who sell pheromones which are supposed to mimic the natural pheromones that women find attractive. You mileage may vary. Personally, I very much doubt there's any magic short cuts; dress sharp, be nice, be confident, and search for women who are interested in the same thing as you (be that a one night stand or a longer-term relationship). --Robert Merkel10:56, 6 December 2005 (UTC)[reply]
Pretty much the biggest attractors (varying in importance for a given woman) are a great personality, confidence, money, looks, and talent. If you have at least one of the five and are persistent enough, at least some women will be attracted to you. Playing the numbers game works pretty well to, partly becaue it takes confidence. Ask 20 women out and have something interesting to say and you'll probably be successful with a lot more than one. You can of course work to improve on as many of the above five as possible, but confidence alone does work. - TaxmanTalk13:37, 6 December 2005 (UTC)[reply]
great summary :) "confidence alone does work" is only too true, sadly leading to the spawning of legions of male jerks. So if the question is intended to read "any woman" rather than "a particular woman", your best bet is to become a megalomanic jerk. dab(ᛏ)13:43, 6 December 2005 (UTC)[reply]
(assuming you're a guy) I once did a little unofficial field (street) study of what type of men walk around with pretty women and I found that they could be roughly classified as either 'bikers' or 'yuppies' (this was in the early 1990's). So my conclusion was that (pretty) women are attracted to men with power, be it physical (old style power) or financial (new style power). In an evolutionary sense this makes sense because the offspring needs to be protected. That creating offspring is nowadays hardly a reason to start a relationship is irrelevant. It's the environment we evolved in that determines our sexdrives (which 'love' and such basically come down to - excuse me for being so down to Earth). Of course this is related to the confidence thing; you can also fake it. And the 'dressing sharp' fits in with the yuppie type (for the biker type 'sharp' is not quite the word). Finding a woman who is interested in the same things as you sounds logical, but I have my doubts. Studies have shown that people can 'sniff out' those with a different DNA-makeup, to whom they are more attracted. This also makes sense evolutionarily. If same-type people were mutually attracted that would be sort of inbreeding. I mean the 'sniffing out' quite literally - smell seems to be an indicator for this. So if you want this to work, you shouldn't really wash too often and certainly not use soap. So why don't I have a woman then? :) DirkvdM14:47, 6 December 2005 (UTC)[reply]
ナイトスタリオン ✉ 12:08, 6 December 2005 (UTC)
