Wikipedia:Reference desk/Archives/Science/2007 February 2

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February 2

Appendectomy and oxygen

Is it normal for a person who has undergone an appendectomy (burst appendix) to be on post operative oxygen?--Light current 01:31, 2 February 2007 (UTC)

THis would be for a person abot 70 years old.--Light current 11:46, 2 February 2007 (UTC)

I was about 5 when it happened, but I remember them putting tubes down my nose, so I wouldn't think it'd be somewhat normal. It is a potentially fatal thing. --Wirbelwindヴィルヴェルヴィント (talk) 03:59, 2 February 2007 (UTC)

For any procedure involving general anesthesia, and intubation, one can expect to wake up with an oxygen mask on, especially at an advanced age. High oxygen will help a patient overcome the trauma of the surgery, and more important it will help that patient clear infections from the perforation and the surgical insult. ^tucker/_rekcut 12:11, 2 February 2007 (UTC)

Ah thank you. Just the ans I wanted!--Light current 12:12, 2 February 2007 (UTC)

Best position to land

When falling from high up (for example, a fifth storey), what would be the safest position to land when hitting solid ground? --Codell ^{[ Talk]} 02:39, 2 February 2007 (UTC)

[1] [2] -- Consumed Crustacean (talk) 02:43, 2 February 2007 (UTC)

Dunno if it was ever proven, but I'd always heard if you can somehow pull off a rolling landing, you could possibly survive (height depending of course). Cyraan 02:51, 2 February 2007 (UTC)

Thank you, Consumed Crustacean. This answers my question.--Codell ^{[ Talk]} 03:47, 2 February 2007 (UTC)

as far above the ground as possible

How to draw: trans-3,5-dibromocyclodecyne?

This is the only problem I can't do for my alkyne nomenclature homework. I submitted the structure, but the program keeps telling me to show the trans configuration of the Br Atoms.But I'm pretty sure I put the Br atoms where they're supposed to be.I'm also sure that I have the cyclodecyne structure right, so it must be something else I'm missing.I tried all combinations of where the Br are located respective of one another.Because it's trans, I'm guessing that one of the Br atom is inside the ring, and the other on the outside.I tried that, but it wasn't correct.Any ideas?Thanks in advance 128.163.214.199 03:06, 2 February 2007 (UTC)

By saying "inside" and "outside", you're thinking about the ring and everything attached to it as being flat. Ain't so...visit your textbook chapter about alkanes or orbital hybridisation to see why things attached to the ring are often described as "above" and/or "below" the plane of the ring, never inside/outside the ring. DMacks 03:14, 2 February 2007 (UTC)

from trans "A similar phenomenon is seen in cyclic compounds (in which the atoms form a closed ring), where substituents can be on the same "face" of the ring (cis) or opposite faces (trans.)" - so agree with above - it's above or below the plane of the ring.87.102.4.6 11:06, 2 February 2007 (UTC)

Geometric isomerism has more details, and a diagram for the cycohexane case.87.102.4.6 11:07, 2 February 2007 (UTC)

3,5-dibromocyclodecyne is chiral at both the 3 and 5 positions, usually a trans structure refers to atoms on opposite sides of a thing (atom, double bond) - it sounds like you need to know the most stable conformation of the molecule and put the bromines on opposite sides. In actuality the name you've got doesn't seem to be a useful description of the molecule - I'd expect something like R,R 3,5-dibromocyclodecyne, R,S 3,5-dibromocyclodecyne, S,R 3,5-dibromocyclodecyne, S,S 3,5-dibromocyclodecyne.87.102.4.6 10:31, 2 February 2007 (UTC)

Thanks a lot, everyone. I misinterpreted the diagram in the book; somehow I didn't look at the type of bond (up/down). Now I understand the concept better.128.163.224.201 18:08, 3 February 2007 (UTC)

Time for Escape!!!

How long would it take to accelerate human passengers in a craft to about eight miles per second, and lets say they are traveling at a constant 3g?67.127.96.131 03:39, 2 February 2007 (UTC)

Sorry, but we don't answer homework questions! But to help you out: have a look at the acceleration article, you'll notice the following equation:

$\mathbf {\bar {a}} ={\mathbf {v} -\mathbf {u} \over t}$

Using that, you can find the time required. All the best. - Akamad 03:48, 2 February 2007 (UTC)

Oh man thank you someone finally gives me an equation and thank you but this is not homework I am just very curious about these things.67.127.96.131 05:19, 2 February 2007 (UTC)

Yes, I am similarly curious about how long it will take a train leaving Philadelphia traveling at 180 km/h to reach a train that has left New Jersey traveling at 200 km/h. But of course, not for my homework! − Twas Now ( talk • contribs • e-mail ) 06:50, 2 February 2007 (UTC)

Several of the times when I've tried it, Amtrak or New Jersey Transit has had equipment failures. Where does that go in the equation?

Atlant 14:04, 2 February 2007 (UTC)

We surely don't want to confuse the questioner, but this equation might be helpful as well.

$x(t)=x_{0}+vt+1/2at^{2}$

$v(t)=v_{0}+at=dx(t)/dt$

Nimur 08:42, 2 February 2007 (UTC)

Awesome eqautions but once again it's not homework and believe it or not I haven't ever had a physics class. Someone just please tell me how to plug in the numbers.

What you want to do is solve the equation (the equation I gave you, the first equation that Nimur gave is for finding displacement, and the second equation is the same as the one I wrote down) for t (the time variable). Here is a link on how to solve equations if you need help: http://www.sosmath.com/algebra/solve/solve0/solve0.html. You already know the final velocity (8 miles/second) and the acceleration (3g). From your question, you can assume the initial velocity to be zero. So all the variables are known. But make sure all your units are the same (for example, you'll have to change the 3g to miles/second/second, have a look at this article: Earth's gravity for what the "g" means. Hope that helps. - Akamad 11:17, 3 February 2007 (UTC)

Okay, I'll assume good faith and give the answer. The simplest form of the relevant equation is just v = at: speed (assuming you start from 0) is acceleration times time. So t = v/a: time is speed divided by acceleration. g is 9.8 m/s², so the acceleration 3g is 29.4 m/s². 8 miles is 12,875 meters, so 8 mi/s = 12875 m/s. So the answer is 12875/29.4 = 438 s (see, dividing the units of m/s² by m/s gives seconds) or 7.3 minutes. I've rounded the numbers along the way since I assume the 8 mi/s was not intended to be an exact number. --Anonymous, February 3, 2007, 22:02 (UTC).

Okay thank you because I did attempt to do the eqaution given to me by Akamad and I ended up with 8.76 hours! The reason why I asked this I wanted to know if the speed could be acheived without killing the passengers. Now the next problem to face is making it through the atmosphere without burning up or the craft loosing velocity. Anyways everyone thank you again.

Note that real-life space launches achieve orbital velocity of about 5 miles/second without killing the passengers. Achieving 1.6 times the speed could be done by accelerating 1.6 times as long. (In practice the acceleration is not constant, so it's a bit more complicated than that, but that'll do for a rough idea.) --Anon, Feb. 4, 05:05 (UTC).

Light

Greetings,

I have done small studies an have a theory. Light has mass and weight. It must, because a black hole pulls in light. I don't understand the technical jargon. Please let me know if it has mass. (In layman's terms)

Fare thee Well, AlexanderTG 05:58, 2 February 2007 (UTC)

What is your theory? This sounds like the wave–particle duality of light. − Twas Now ( talk • contribs • e-mail ) 06:52, 2 February 2007 (UTC)

General Relativity is exactly the technical jargon which explains how gravity can "pull" something (like light), even if it has no mass.Some people try to explain this by saying that the gravity bends space and time.It is very well established that light has no mass, and many experiments and equations exist to back this up. Nimur 08:44, 2 February 2007 (UTC)

You might also consider General Relativity at the Simplified Wikipedia if you are having difficulty with technical jargon. Nimur 08:46, 2 February 2007 (UTC)

Also, what do you mean by mass? Mass in general relativity is very complicated and may not be well defined at all. --Spoon! 09:25, 2 February 2007 (UTC)

Short answer - light is made up of photons; photons do not have rest mass, but they do have relativistic mass, because they have momentum. This article answers the question "If light has no mass how can it be deflected by the gravity of a star?". Gandalf61 14:12, 2 February 2007 (UTC)

They say gravity bends space, but the experiment they do to show this where the balls roll toward each other only works because of the earths gravity below it:( Is this because they can't find any real way to show what is happening, and are hoping we don't notice, or am I missing something important here:(Hidden secret 7 20:54, 3 February 2007 (UTC)

You didn't miss anything - the bending thing is bogus. The reason light is attracted to black holes is that is has mass, just like any other particle. True it doesn't have rest mass, but that doesn't make the mass any less real. There is no need to invent bending of space or anything like that. Ariel. 13:19, 4 February 2007 (UTC)

Ariel's comments are a simplification which may adversely affect the original questioner's understanding. It is not correct to say that light has mass in the conventional sense. As noted above, in certain treatments of relativity, the semantics of "mass" can be redefined, but this is playing games with human language and word choice. The "bending thing" is another way to work out the equations. After all, science is just a model of our universe, not a perfect description. Nimur 03:33, 8 February 2007 (UTC)

donut constellation

There seem to be models for ethernet structures described as a donut constellation. The descriptions of the structure are too technical for me to understand. I have heard the term donut constellation used to described the way energy revolves in some physical structures as well. The philosphers Deleuze and Guattari describe social maps and organizations that evolve rhizomatically along a number of axi and levels. As a result many creative and visual thinkers use this structure as an exploratory model. I think the donut constellation whereby energy is constantly revolving on a number of planes around a vacant middle maybe used to as an alternative model for describing the way chunks of the creative thought process evolves. I would like to read more about this type of structure. I think there is a more accurate word, that those versed in physics would use to describe it.

The word is torus, the surface is represented by a quartic equation in three dimensional space. As for a doughnut shaped ethernet this would be a ring shaped data bus with various data items branching off it.87.102.4.6 10:24, 2 February 2007 (UTC)

Antagonism vs Inhibition | Enzymes & Neurotransmiters

• On the other hand, compounds that inhibit reuptake but also inhibit release of dopamine, such as Wellbutrin and vanoxerine, have mild stimulant effects and little abuse potential, and can be used to treat stimulant addiction.

• Zyprexa's antipsychotic activity is mediated primarily by antagonism at dopamine receptors.

Scientifically speaking, is there any differece between Antagonism and Inhibition? Please provide references to back up your answer.

I would appreciate the answers provided. Thnx. --Parker007 12:37, 28 January 2007 (UTC)

I'd suggest that the usage choice is a language one, (I can't call a difference between the two). Medical dictionary (is this a good source?) has the two lumped together for the same definition see http://www.wrongdiagnosis.com/medical/inhibitor_antagonist.htm

The real difference is actually in other usage - an antagonist 'works against' eg pairs of muscles that pull on either side of the bone, an inhibitor prevents the action itself. I'm not sure that in biochemical usage the distinction is made (of perhaps even known).

Also http://www.thefreedictionary.com/antagonist defines antagonism in a biochemical sense as "Biochemistry A chemical substance that interferes with the physiological action of another, especially by combining with and blocking its nerve receptor" eg as an inhibitor.

So in biochemistry they seem to have the same meaning - though if more becomes known about the mode of action of a given substance perhaps in the future a distinction will be made.

Comment on proper usage...

For instance a compound that causes dopamine uptake is antagonistic to a compound that causes dopamine release - but does not inhibit.

Whereas a compound that binds to a site causing dopamine release (not activating it) can be called an dopamine release inhibitor. (But may also be decribed as antagonistic to a compound causing dopamine release by the nature of it's inhibitory action). Hope that helps.87.102.33.144 13:04, 28 January 2007 (UTC)

Actually, antagonism and inhibition are two distinct concepts in most biomedical contexts. Antagonism usually refers to interference with the action of a substance, or sometimes to the production of an effect that opposes that of another substance. An example of a steroid antagonist is spironolactone, which reduces mineralocorticoid effects and androgen effects. Inhibition usually refers to interference with production of a substance. An example of an inhibitor of steroid production is metopirone. alteripse 17:22, 28 January 2007 (UTC)

I see that competitive anatagonist, noncompetitive antagonist & uncompetitive antagonist need articles...I'll have to work on that.

For maybe a litle semantic clarity of the difference between antagonism and inhibition...Inhibition is the prevention of some event and antagonism is one biochemical pathway through which one might cause inhibition. Enzymes or biological receptors, for example, can be inhibited by several means (phosphorylation state, missing co-factors, pH, etc.), including antagonism. An antagonist may inhibit by one of several methods (see below), but chiefly it interrupts the the otherwise natural activity of the enzyme/receptor in the local state. Types of enzyme inhibition | Competitive inhibition | Uncompetitive inhibition | Non-competitive inhibition | Suicide inhibition | Mixed inhibition | -- Scientizzle 00:22, 30 January 2007 (UTC)

I am inclined to agree with User:Alteripse & User:Scientizzle, otherwise I wouldn't have asked the question, because I already read the dictionary before asking the question. --Parker007 05:52, 2 February 2007 (UTC)

Wow, so biochemists can just make up new definitions of words can they! If 'you' used the words in correct context of their english meaning maybe you wouldn't have this problem???87.102.4.6 10:38, 2 February 2007 (UTC)

I'd just like to point out that we do have articles on Receptor antagonist and agonist, as well as the featured atricle Enzyme inhibitor, which also was linked to above. It might be better to expand on those, and add some redirects, rather than create new articles. --NorwegianBlue ^talk 09:24, 2 February 2007 (UTC)

Yeah...I know. I was considering how best to go about either combining receptor dynamics into the enzyme inhibition articles or making new, separate articles. Receptors and enzymes are very unrelated in terms of activity, and are separate targets for drug interactions (through which most antagonism occurs), but the molecular methods and pharmacological models of inhibition are largely similar...I'll figure it out... -- Scientizzle 16:14, 2 February 2007 (UTC)

How do enzymes have anything to do with neurotransmitters? --Parker007 09:41, 2 February 2007 (UTC)

Enzymes are to substrates as receptors (eg, neurotransmitter receptors) are to ligands (eg, neurotransmitters). --David Iberri (talk) 01:19, 3 February 2007 (UTC)

That makes no sense; So what does enzymes do to neurotransmitters? --Parker007 00:10, 4 February 2007 (UTC)

What David Iberri is trying to say is that the interaction between enzyme-substrate is analagous to receptor-ligand. The kinetics are often very similar. -- Scientizzle 07:31, 4 February 2007 (UTC)

In english? :) --Parker007 06:11, 9 February 2007 (UTC)

An enzyme binding to its target substrate exhibits very similar kinetics as a receptor binding a signaling molecule. The final action is different (enzymes will alter the substrate in some way, a receptor will activate a distal signaling pathway, without altering the signaling molecule), but the modeling is similar. Is that any better? -- Scientizzle 16:02, 9 February 2007 (UTC)

Thank you for your reply Scientizzle, but I am going to read all the above articles after Feb 15 as I have final exams for some part-time courses I am taking. If this question gets archived, and I have some further clarification, I may revive it (hope thats okay with you). Andthankyou for creating the redirects. --Parker007 07:24, 11 February 2007 (UTC)

Bending of light.

Why does a light ray bend when there is mass in vicinity of it's line of journey? Considerable bending has been observed when the amount of mass is large.Does bending occur even when amount of mass is small?Is there any relation between gravity and electromagnetism?Well, something fishy is going on.I think unification of gravity and electromagnetism is not far.(Ecclesiasticalparanoid) —The preceding unsigned comment was added by 210.212.215.141 (talk) 10:13, 2 February 2007 (UTC).

• Light is an odd thing. It can behave both like a wave and like particles. Since particles have mass, they are affected by the gravitational pull of a mass in its vicinity. Light probably bends too when the mass is small, the effect is just smaller. 'Small' is a relative term in that case. Usually we're talking planet-sized masses in discussions like this. - Mgm|^(talk) 10:59, 2 February 2007 (UTC)

At the moment there is no known way to unify gravity and electromagnetism into one force though it is presumably the goal of a Theory Of Everything. Many people have sought such a connection, including Albert Einstein (see Unified field theory), and failed. Whether it is far away or not probably depends on whether you think they are going the right direction with string theory or not. --24.147.86.187 13:33, 2 February 2007 (UTC)

Unless I'm mistaken, classical electromagnetism and modern gravitational theory (general relativity) have already been shown to be consistant.My answer to your last question contained a link to Kaluza-Klein theory, which shows that Maxwell's equations (the basis of classical electromagnetics) can be derived from principles in general relativity.In other words, KK theory more or less united modern gravitation theory and classical electromagnetics back in the 1920s.

Also note that it isn't just light that exhibits wave-particle duality, but all matter at sufficient scales.However, pertaining to the question you originally posed, I'm not sure if it's totally appropriate to embark on a discussion of quantum mechanical effects (which is where you would consider wave-particle duality).In general, QM and GR haven't been reconciled, so I don't know if it's appropriate to talk about wave-particle duality in the same breath as gravitational (spacetime) effects on light.Look at Maxwell's equations in curved spacetime and General relativity.Perhaps a physicist can fill in some of the gaps I've omitted in my explanation...I'm definitely not a GR person, and I can only do fairly basic QM.

P.S. - The photon is massless (at rest). -- mattb @ 2007-02-02T13:42Z

I believe the current understanding is that the light really doesn't bend. It travels straight in spacetime and it is spacetime itself that is distorted by the presence of the mass. The analogy usually used for us non-physicists is to imagine spacetime as a rubber sheet and the massive objects as heavy objects pressing down into that rubber sheet. The depressions thereby formed are analagous to the bends in spacetime.

Atlant 14:07, 2 February 2007 (UTC)

Light also distorts space-time depending only on it's frequency. The fundamental understanding of Einstein's theories is that Energy and Mass are equivalent. --Tbeatty 07:09, 3 February 2007 (UTC)

If i remember correctly Lightning consist of Plasma, which is a super hot gas; gas has mass. in anyway if your talking about lightning i can see why it would bend, however if you were talking about regular light, light accelrates Ions or electrons or something (someone here should know) in anyways these ions or electrons also have a mass (although its not much its still there) that would explain how a high gravity mass can alter light in such ways. Maverick423 15:07, 2 February 2007 (UTC)

Nobody said anything about lightning as far as I can tell.Please don't take this the wrong way, but given your second sentence I would suggest reading some of the linked articles.The article on light itself provides a pretty good overview. -- mattb @ 2007-02-02T15:13Z

Meh sorry and thanks for the corrections its been a while since i read or studied about light so i can get my info confused at time =( Maverick423 15:32, 2 February 2007 (UTC)

No need to apologize.I'm by no means an expert on modern physics, and I've probably said some things that aren't totally accurate.Just take a moment sometime to read that article on light. -- mattb @ 2007-02-02T15:40Z

Statistics/Normal Distribution

(repost of a question previously posted on another reference desk and previously moved to the math desk. Te Q and A have been moved there as well. Please do not doublepost.)Edison 16:17, 2 February 2007 (UTC)

Another poision question

Hi there again its me! im sure you know me from my old question from radiation =P anyways here i go again. my curiosity has gotten Intrested in the cyinade (think thats how its spelled). Cyinade Poisioning yes it says its fast and kills rapidly, but exactly how does it do it? What does a person feel (yes i am intrested in stuff like this as you can see) when they get cyinade poison? does the skin melt does the person feel immense pain or is it just a drink and fall dead with no feelings of the poison coursing through your body?? what about the range of cyinade? how far can it reach if a cup of it was spilled on the floor and how fast does it evaproate? there are lots of questions about this i want awnsered but well i dont know if people sugar coat it when they talk about it or what but please guys DONT sugar coat it i am intrested in the raw effects of it. thanks Maverick423 15:24, 2 February 2007 (UTC)

Ok try not to get carried away - the skin does not melt.

Cyanide poisons (in one way I know of) by complexing to metal ions such as the iron in haemoglobin - (it may be poisonous in other ways) - this is similar to carbon monoxide poisoning - effectively you aspyhyxiate due to lack off oxygen.

The 'cyanide capsule' is often sodium cyanide solution.

Hydrogen cyanide is a gas and also poisonous.

In the case of swallowing cyanide choking and spluttering occurs - followed by loss of conciousness - the death. There is not much pain - but the choking and spluttering is unpleasant but not that bad.. People poisoned by cyanide can be saved - the longer they are out the less chance they have of surviving.

Sodium cyanide and potassium cyanide are solids - as solutions they may produce a small amount of hydrogen cyanide - adding an acid to a cyanide salt will produce the hydrogen cyanide gas - this is capable of spreading - I don't know how fast though.

Interestingly hydrogen cyanide will burn.

The cynanide links above all give more info on mode of action and lethal doses etc. Suggest you read them..87.102.4.6 15:49, 2 February 2007 (UTC)

Alright great info man thanks much! so then what they say about cyanide being a quick and painless death is a lie? i kinda figured there was something about that line. well anymore information is greatly appreciated as for me i got some stuff to look at thanks again! Maverick423 15:57, 2 February 2007 (UTC)

I'm afraid much of the above is incorrect. Cyanide does not act on hemoglobin, but on cytochrome oxidase, as a metabolic poison. Cytochrome oxidase is an important electron carrier in the electron transport chain. It is a necessary component of mitochondrial respiration, and without it the mitochondria are not able to induce a proton gradient for their ATPase. Cyanide binds to cytochrome oxidase and renders it useless. Also, death from cyanide poisoning would probably not be very painful; first, it only takes about a minute to become unconscious with a reasonable dose, and second, reduced ATP would not be likely to initiate nociception in the appropriate nerves until long after a victim was unconscious (if at all). Usually the "choking and spluttering" described above does not happen while the patient is conscious. A time course might look like this: cyanide is introduced to bloodstream, cyanide enters central nervous system and renders the (high ATP consuming) neurons unable to function, unconsciousness occurs, cyanide in heart renders Ca++ uptake/sarcomere resetting impossible via reduced ATP, cardiac arrest occurs, rest of cells in body die either from cyanide exposure/ATP paucity or anoxia resultant from cardiac arrest. ^tucker/_rekcut 22:52, 2 February 2007 (UTC)

thanks much for the corrections and thanks much IP dude for telling me about the corrections on my talk page =). I will ask another question about the information on the bottom in a bit because by this time many people dont read this far up. Maverick423 22:44, 5 February 2007 (UTC)

body temperature

How do you raise your body temperature? —The preceding unsigned comment was added by Andiman56 (talk • contribs) 15:26, 2 February 2007 (UTC).

Ahh good one well there are many ways to do this. one such way is exercising. the other is involenttary shivering in the cold. Maverick423 15:33, 2 February 2007 (UTC)

Give it better fuel. Vranak

Put more layers of clothing on. Eating spicy food feels like it does too, but I don't know if it does. A hot drink and hot food. Lower your exposed surface area by huddling as tightly as you can. Skittle 17:25, 2 February 2007 (UTC)

Spicy foods actually help lower body temperature. Thats one of the reasons why they are consumed in warmer climates. --Russoc4 04:18, 3 February 2007 (UTC)

Indeed. You eat spicy foods, which causes you to sweat, which leads to puuuuuuure coolness! − Twas Now ( talk • contribs • e-mail ) 09:00, 3 February 2007 (UTC)

Increase the speed of your metabolism, so you produce heat faster from your food:)Hidden secret 7 20:56, 3 February 2007 (UTC)

Feeling Gassy

Are there foods that I can eat during the day (at work) that causes the LEAST gas?I seems that no matter what I eat, I end up feeling uncomforatable all day or until I relieve myself...

As you know, we can't give medical advice. But I think it's safe to mention that any carbonated beverages (such as soda) will free their carbon dioxide gas inside of you and it's got to go somewhere.

Atlant 16:19, 2 February 2007 (UTC)

This shouldn't be a request for medical advise.If you would like for me to rephrase it, what type of foods would cause the least amount of gas produced in the stomach for humans?I am assuming that vegatables like broccoli is one of the culprits, but what other types of foods?

Peppermint tea can help settle the gastrointestinal system.Vranak

Flatulence#Causes may be of some help -- WikiCheng | Talk 10:56, 3 February 2007 (UTC)

I heard ginger is good for seyyling the gutts

Muscle Cramps

I infrequently get cramps in various muscles.Most often in my calves.However, I have found that I can make myself get these cramps very easily by holding my calves or bicepts in a flexed position.My question is what do these cramps do to the muscles in which they occur?Is it like lifting weights at all, or is it somehow detrimental?Thank You. —The preceding unsigned comment was added by 66.99.100.66 (talk • contribs).

How does your leg feel afterwards – better or worse? Vranak

I don't have an answer to your question, but FYI a common cause of calf spasms is calcium deficiency. Anchoress 17:16, 2 February 2007 (UTC)

CD28 gif 3d rotating structure

I really enjoyed the rotating 3d image of CD28 on your CD28 page.My question is simply that I would like to know if I could use your .gif format software (code) to portray the 3d structure of another protein molecule for which I have the .pdb file (3d coordinates)on my website?Can you please help me with how to do this if it is indeed legal?Thanks again for another terrific Wikipedia page, as always!

Don Kaiser <Rm email to reduce spam>

• If you click on the image, you will find yourself on a page that indicates who created it...ask him how he did it. I've used the free Jmol program to make 3D molecular models from PDB files. I think it can export animated gif images, but not sure. DMacks 20:48, 2 February 2007 (UTC)

Plantiferitus

Plantiferitus... what is this word? It is a very painful foot condition and I can't remember it. [Mαc Δαvιs] X (How's my driving?) ❖ 18:18, 2 February 2007 (UTC)

Have you tried at "foot.com" http://www.foot.com/info/info_cond.html Plantar fasciitis. ?83.100.183.48 18:30, 2 February 2007 (UTC)

abnormal oozing of blood from skin,teeth etc

recently came accross a person suffering from peculiar problem of loosing blood from skin,has already supplemented 3 bottles of blood in last 2 year.Seems condition is detoriaoting day by day.Blood report are about to come in few days.Pls advice. —The preceding unsigned comment was added by 59.93.247.53 (talk • contribs).

Have them see a doctor. Considering that a blood report is being performed, it seems this if being taken care of. We can not provide medical advice. -- Consumed Crustacean (talk) 18:55, 2 February 2007 (UTC)

Think this person your talking about might have Hemophilia. im not sure but u might wanna check it out and compare. Maverick423 20:30, 2 February 2007 (UTC)

Are you the patient, a friend of the patient, the nurse, or what? Your IP suggests Australia. Don't they have an established health system there which could diagnose and treat the problem? Edison 03:40, 3 February 2007 (UTC)

hovercrafts

Is it possible that in the next 20-30 years, we would have hovercrafts as a normal mode of transportation replacing automobiles?

I think it's unlikely since hovercrafts expend (quite a lot of) energy just to keep themselves of the ground - so I'd suggest that they are intrinsically less efficient. Plus they are not as easy to steer as cars especially in a high wind - they definately wouldn't be good on motorways - unless they had big bumpers like dodgems. Given that it seems important to increase fuel efficiency I think the answer is definately most unlikely.83.100.183.48 20:18, 2 February 2007 (UTC)

i dont know about hover cars however i do know that this car has been in prototype testing for quite some time and is already being considered for mass production soon! check out the Moller Skycar Maverick423 20:36, 2 February 2007 (UTC)

That's what they told us 10 years ago about that Skycar... Face it, it's not going to happen. — Kieff | Talk 21:42, 2 February 2007 (UTC)

Aw kieff come on its possable sooner now then later. after all they are getting the permission from that agency that says its ok to fly them. since the car is also in production and has actually flown, the chances of it comming out soon is great. Moller said his car was going to come out by 2008 and then mass produced by 2012. people have already bought the car itself and are going to recive it soon. also in Iran they are also making a flying car that is going to be used in rescue and police related instances. http://www.cnn.com/2007/TECH/01/31/israel.flying.car.ap/index.html http://www.moller.com/purc.htm

Maverick423 21:55, 2 February 2007 (UTC)

Flying cars - are you mad - I can just imagine coming home oneday and finding one sticking out of my roof.. Hopefully never83.100.183.48 22:14, 2 February 2007 (UTC)

dont ya worry the flying car has full safety features including backup engines, full car parchute, GPS locater, Automatic GPS Driver. simply enter the place you want to go and sit back and read a book the car will do the rest itself! Read Mollers Website to find out more on the car itself. Crashes will be reduced massively! Maverick423 22:50, 2 February 2007 (UTC)

The thing has barely hovered so far, and this project has been going on as far as I can remember. I can't see something like that becoming mainstream and affordable in the near future. — Kieff | Talk 01:34, 3 February 2007 (UTC)

Ah but the smaller version of the car has already flown across the country in previous test. its smaller (1 passenger) and ligheter and has more power (10 Engines 5 main 5 back up) instead of the 8 (4 main 4 back up). it goes faster and uses less fule since it is lighter. i think the problem with the 4 passenger one is that it only has 8 engines and uses more fule its less how can i say it? well i guess cost effectiveness is less for that one. think the smaller version has already been proven to go 64 miles per gallon then the bigger version (which only hovers) at 20 miles per gallon. tell ya what ill get back to you with this one i just need to make sure k. Maverick423 20:05, 3 February 2007 (UTC)

ahh sorry here it is it appears that the smaller version has this http://www.moller.com/m150.htm ( i took out the list that i placed cause it was bigger then i thought so i just linked it for ya ((should of done that to begin with))) well those are the specifications on that 1 passenger one so the engines are acctually 2X2 enginesMaverick423 20:22, 3 February 2007 (UTC)

I really don't expect a project like this will ever get off the ground:@Hidden secret 7 21:00, 3 February 2007 (UTC)

Acctually from what i heard the plane and the car were both being considered for use in public travel. the only problem was that planes were more expensive to buy then cars used more fule and needed a flat surface to take off. that is what made the car as the primary mode of transportaion. if these issues were assest from the begining we would be saying traveling on the ground is impossable or primitive. Maverick423 15:26, 5 February 2007 (UTC)

Do Snails Have Eyelids?

I was wondering if snails have eyelids.

Thanks!

It seems not - but the eyes are on muscular stalks and can be retracted - in fact snails don't have very good eyes apparently - relying more on touch and taste - the entire body is a bit like one big tongue.

See this website http://www.applesnail.net/content/anatomy/senses.php for more info on one type of snails eyes - a bit of the way down there's an diagram/image showing just how bad their eyesight is - it's probably not worth them having eyelids anyway.83.100.183.48 20:38, 2 February 2007 (UTC)

Deep Fat Frying

Does deep fat frying potato chips (including the skins) reduce the nutritional value? I don't care about the fat that's added (I only eat them on occasion) but rather the nutrients that may be leached out or otherwise rendered useless. --Seans Potato Business 20:45, 2 February 2007 (UTC)

Some vitamins, Vitamin C for example (and including other water-soluble vitamins if I'm not mistaken), are sensitive to high cooking temperatures. Although this section seems to contradict what I said (but note the fact tag), so maybe my belief is in error. Anchoress 21:09, 2 February 2007 (UTC)

Flash frying (don't know if we have an article) preserves many sensitive compounds due to the short time the stuff in the the pan - plus I don't think water solubilty has a lot to do with it - that would be boiling - it's all a matter of degree - it's usually air (oxygen) that degrades vit C - so a minute at 200C probably won't make much difference - though obviously prolonger frying will degrade all the nutrients.83.100.183.48 21:23, 2 February 2007 (UTC)

As a rule I'd say no - with modern preparation methods the degredation is very small - the time on the shelves way have a bigger role - though if the food package is airtight/block out light this shouldn't be a problem either - In general the nutritional value is increased by frying - by virtue of the increase in calorific value due to the fat; this doesn't apply if you are supposed to be on a diet obviously..83.100.183.48 21:27, 2 February 2007 (UTC)

Need help at Big Bang

There are some edits there today that I don't agree. Can we have some physicists over at Big Bang? Thanks. Xiner (talk, email) 20:52, 2 February 2007 (UTC)

Christ - good luck - as the big bang is speculative (or not if you're a big bang scientist) - this entire topic is open to original research and speculation. For instance this difference http://en.wikipedia.org/w/index.php?title=Big_Bang&diff=105174931&oldid=105171230 replaces expands on something that is already purely speculative - what is one to do?83.100.183.48 21:02, 2 February 2007 (UTC)

However if the edits get too much for you, you can always fall back on our good old friend - use {{fact}} - I'd suggest removing debateable parts to the talk page - stating your reasons for the removal and suggesting that adequate citations are provided before it's readdition.83.100.183.48 21:06, 2 February 2007 (UTC)

Plus there are so many variants on this theory in terms of explanation and outcome that you've got a real minefield..83.100.183.48 21:10, 2 February 2007 (UTC)

Could you say which edits were problematic?83.100.183.48 21:10, 2 February 2007 (UTC)

Actually, the one you pointed out is the one I'm having most trouble living with. I don't mind speculations, but this guy is putting things down as fact, with no way to check its veracity. He's editing a lot of articles too. Xiner (talk, email) 21:20, 2 February 2007 (UTC)

I'd suggest the method of removing and asking for citations - that's the way here I've learnt - even if the guy's right... Mention that the information must be verifyable - see Wikipedia:Verifiability "The threshold for inclusion in Wikipedia is verifiability, not truth" that's official policy.

It looks like they are adding fairly respectable explanations-I wouldn't expect it to be difficult to find citations for them - but I doubt that those explanations are the only subsets of the theories out there..I'm sure there are many other ones - The article might need a rewrite to cover the various possibilities and explanations thereof - with a non-contentious introduction.

I'd say the second paragraph about the 'origin from nothing' either has or should have it's own article - the info is relevant - but I'm not sure how much in the context of the article being called 'big bang' - it would be worth pointing out that the two theories are consistent in this respect - but I don't think in the main body of the article - maybe in a 'comparison with other cosmological theories' section. If the two were inconsistent that would be worth noting too.83.100.183.48 21:48, 2 February 2007 (UTC)

I see. I'll see what I can do. Thanks a lot for the advice. Xiner (talk, email) 22:04, 2 February 2007 (UTC)

By the way I do it like this (on the talk page):

..Removal of .... ..

I removed this text "the x is y because of z" because I'm unsure/think it's wrong/think it's exaggerated/think it's in the wrong place...

Could somebody please provide a reference for this infomation before re-adding it.

or

This is not relevant to the section it's in and should be in a new/existing section - I will/could you create such a section..

or

Shouldn't this be in a separate article - named '....' -

I wouldn't recommend just removing stuff without pasting it to the talk page - that can be annoying/seem aggressive.. (unless of course it is obviously vandalism - not the case here).

If you copy debated stuff to the talk page then they can discuss it there or they haven't got a leg to stand on - separates the reasonable from the unreasonable people. Also (from experience) if someone makes grammatical changes - don't revert - make little edits (taking into account their addition) until the article is satisfactory to all of you - that works too (though it can be very time consuming) -

I don't envy you...probably one of the worst articles to have on your watchlist, jesus, and george bush being slightly worse.83.100.183.48 22:10, 2 February 2007 (UTC)

Stick bomb.

I was reading the article stick bomb and a quick google search on it didn't really tell on how to construct one. Is there a website that shows how, that perhaps I missed? --Proficient 21:34, 2 February 2007 (UTC)

I agree that there should be the basic popsicle stick bomb I made as a kid. Somebody will have to whip up the 3D software and make a model! (Perhaps me, one day). --Zeizmic 22:10, 2 February 2007 (UTC)

Is that article a copy-vio, or is it just really weirdly written? I can't see any of it on Google, but Google isn't the world. I've never heard of stick bombs before, so I can't really do more than remove references to an 'Author'. Anyone here able to improve it? Skittle 22:43, 2 February 2007 (UTC)

Me neither, and I'm guessing that's not their running name then. The current article is an obvious self-promotion by that Tim guy, so if you guys think this stuff is notable enough for an article, rename, rewrite and get us some sources. — Kieff | Talk 01:30, 3 February 2007 (UTC)

This video has instructions for the type I used to make as a kid: http://www.youtube.com/watch?v=KyzsDmkYnJY 75.138.84.159 00:58, 3 February 2007 (UTC)

The article is being marked for deletion, and there is a big discussion. I made a 3D illustration, and placed it in popsicle. --Zeizmic 16:05, 11 February 2007 (UTC)

Point drag coefficient

Does anyone know the definition of the point drag coefficient? What I know is as follows...

$C_{D}=\int _{-\infty }^{+\infty }{{C_{D}}'\,d({\frac {z}{c}})}$

where $C_{D}$ is the drag coefficient of the aerofoil, and c is the chord length. ${C_{D}}'$ is apparently the point drag coefficient. Can anyone tell me the definition of ${C_{D}}'$? I have the ${C_{p}}$ distribution over the aerofoil, which I presume is needed. Thanks! Readro 22:56, 2 February 2007 (UTC)

The point drag coefficient ${C_{D}}'$ (or section drag $C_{d}$, as I learned it) is the coefficient of drag for a 2-D cross section, with chord length replacing wetted area to nondimensionalize the drag per section span. It seems what you have is the definition, that is if you split the wing into infinitely small cross sections, each cross section will have a section drag coefficient. Integrating all of these over the wing span gives the total drag coefficient $C_{D}$. anonymous6494 00:30, 3 February 2007 (UTC)