Wikipedia:Reference desk/Archives/Science/2013 November 10

= November 10 =

Image quality: 16mm versus DVD/Netflix
If one like classic movies of the 1930's through 1950's and has the option of a 16mm sound projector or a high definition flat screen showing DVDs/Netflix/OnDemand and ignoring the higher cost of obtaining 16mm films, and the higher inconvenience of storing films and changing reels, does the high definition win in terms of image quality (resolution, contrast, color saturation), or does the 16mm projection? Edison (talk) 02:54, 10 November 2013 (UTC)


 * It is possible to buy a digital projector today that will outcompete a film projector from 1950 on every single relevant specification: color accuracy, contrast ratio, optical geometric distortion, acoustic noise, energy consumption, ...  Until fairly recently, contrast ratio was probably the only line-item on which a film projector could meaningfully outperform a digital projector.
 * It is possible to procure a high-definition video stored in a modern digital format that is bit-identical to the source footage. Common video compression schemes yield an output video that is nearly identical to the source video, using lossy compression, but is indistinguishable for most viewers.  The bit depth, resolution, and frame rate of modern digital video systems effectively oversample images compared to the capabilities of 16mm film, so there should be no relevant information loss due to quantization from the analog format - neither in spatial resolution, nor in the gamut of each digitized pixel compared to the gamut of the optical film.  Ken Rockwell has an article on digitized equivalent resolution for several types of photographic film, and the tradeoffs involved.  Motion picture film is usually equivalent to a higher ISO film, so there is less reward for digitizing it at very high resolutions.
 * A video needs to be processed and converted professionally (or at least by a skilled non-professional) to make sure that the digitization does actually preserve all the information that is possible to be preserved. It is very easy to foul up the procedure, and result in digital video that is lower quality than its analog source.  Nimur (talk) 04:05, 10 November 2013 (UTC)


 * Yet on reading that article the conclusion seems to be that each frame of 16 mm would need roughly 1/4 of the data of a 35 mm slide, say 30 Mb. So without any compression, a 6.4 Gb DVD would hold just over 3.5 minutes of uncompressed 16mm film. So all the rest, a factor of say 40 times, must be compression of one form or another. That is rather a lot. Incidentally I have worked for 30 years in the field of digital audio, and am always amused by claims that 'this time we've really cracked the compression problem'. I'd be interested to see the results of ABX testing on video compression. Greglocock (talk) 19:27, 13 November 2013 (UTC)

Momentum vs kinetic energy
If you apply the kinetic energy formulas you will calculate that (for example) a 6 kg projectile with a speed of 1800 m/s has kinetic energy of 10 Megajoules, enough to lift 1000 tonnes 1 meters high. But if you apply the momentum formula you will rescue that in the same conditions the projectile has a momentum of 10800 Ns enough to give 1000 tonnes only a 1/100 m/s speed, that is less than 1 mm elevation. What is the right formula (what would happen in real world)? 79.49.236.203 (talk) 03:39, 10 November 2013 (UTC)


 * You have conservation of energy and momentum, which means that the total momentum and energy of an isolated system will remain the same. If a body collides with another body then you need to consider the system comprising of both bodies as that is then an isolated system. If a 6 kg body collides with a much heavier 1000 ton body, then the kinetic eenrgy of the light 6 kg body will be approximately conserved. This is because kinetic energy equals p^2/(2m) and by conservation of momentum the heavy body will get a momentum of order of the ligher body, it's huge mass means that it's kinetic energy can be ignored. So, the lighter body's kinetic energy is conserved, which means that it will change direction. The heavy body will thus get twice the momentum of the ligher body. Count Iblis (talk) 04:17, 10 November 2013 (UTC)
 * I think the vector relationship makes the worst cast transfer of momentum to be twice the momentum of the original. (i.e ball hits wall orthogonal to it's face and the return direction is 180 degrees). Any impact at an angle will impart less momentum.  This is easy to visualize as the limit of the impact angle gets shallower, there is the parallel limit where no energy or momentum is transferred - i.e. no collision).  --DHeyward (talk) 06:11, 11 November 2013 (UTC)


 * The mistake you made, 79, is assuming that all of the kinetic energy of projectile will become kinetic energy or gravitational potential energy of the 1000 tonne object. This can never be assumed - you never know a priori where the kinetic energy is going to go. Much of it could wind up as heat, for instance. Accurately predicting the outcome of a collision based on momentum calculations requires only knowledge of what type of collision is occurring (elastic versus inelastic, and knowing that there is no splintering of objects helps). Someguy1221 (talk) 06:42, 10 November 2013 (UTC)


 * I assume this a collision? Momentum is always conserved and is a vector quantity.  So you can calculate it two ways:
 * the first way is as an elastic equation where the 6 kg projectile collides and bounces off the larger one. The vector sums of momentum before and after must be equal.  It's elastic so the sum of kinetic energies before and after are equal. The 2 simultaneous equations to solve are $$\,\! m_{1}\vec{u}_{1}+m_{2}\vec{u}_{2}=m_{1}\vec{v}_{1} + m_{2}\vec{v}_{2}$$ and $$\, \! m_{1}u_{1}^{2}+m_{2}u_{2}^{2}=m_{1}v_{1}^{2}+m_{2}v_{2}^{2}$$.  You know $$\,\! m_{1},\vec{u}_{1}, m_{2}, \vec{u}_{2}$$ so need to solve the simultaneous equation for $$\,\! \vec{v}_{1}, \vec{v}_{2}$$.
 * In the inelastic case, the smaller projectile sticks to the larger body and the equations to solve are $$\,\! m_{1}\vec{u}_{1}+m_{2}\vec{u}_{2}=(m_{1} + m_{2})\vec{v}_{f}$$. You solve directly for $$\vec{v}_{f}$$.  After that, there will be a difference in kinetic energy.  $$\, \! \frac{m_1u_1^2+m_2u_2^2-(m_1+m_2)v_f^2}2 = lost\ kinetic\ energy $$.  (someone should check this, it's been a while).  --DHeyward (talk) 10:32, 10 November 2013 (UTC)

I was assuming that the collusion is totally elastic and no kinetic energy is lost. I made this question mainly to know if, to know the power of a projectile, must be considered the momentum or the kinetic energy (i.e. a projectile with a speed of 400 m/s has a force twice or four times higher then another with the same mass travelling at 200 m/s?). In the case I made before, even if it's truce that normally the 1000 tonnes object wouldn't be moved, if the decelaration is higher than 1000 g, the force applied is enough to lift that weight. 95.247.218.92 (talk) 15:04, 10 November 2013 (UTC) PS: solving the equation for inelastic case, the solution is a speed of 1/100 m/s for the whole system, the same I gave for momentum. So is the momentum the right solution? — Preceding unsigned comment added by 95.247.218.92 (talk) 15:22, 10 November 2013 (UTC)


 * No, momentum on its own will not give you the right solution because it does not tell you how the momentum and energy are partitioned after the collision. You need to write down the equations for both kinetic energy and momentum and then solve them simultaneously. I did the maths and found that the projectile would bounce back at well over 1799 m/s. (Obviously this wouldn't happen in the real world because the collision would be highly inelastic. Real bullets are designed not to bounce!) Only 233 joules out of the original 9720000 would be transferred to the target, which is why you got such a small answer for the final speed of the target. --Heron (talk) 16:39, 10 November 2013 (UTC)


 * Yes, as I explained above, you only need to consider the momentum, as the kinetic energy stays (almost entirely) in the lighter body. While you can solve the equations as the other have explained to you, that may obscure the physics of this issue of why momentum and not energy is relevant here. Count Iblis (talk) 16:54, 10 November 2013 (UTC)


 * I now see what you mean, Count Iblis, but I'm not sure that the OP has noticed your factor of 2 (it took me a while to catch up). OP, you need to refer to Count Iblis's answer above and note the statement "The heavy body will thus get twice the momentum of the lighter body." If you solve the momentum equation on its own (p = m1v1 + m2v2), as you appeared to be doing in your original question, you will get the answer for an inelastic collision (0.01 m/s). To get the answer for an elastic collision, you need to double the target's momentum, and you will then get the correct answer of 0.02 m/s. The factor of 2 is not exact, but is close enough when the target is much more massive than the projectile. If you are satisfied with the approximation, you can forget about kinetic energy and calculate solely using momentum. --Heron (talk) 18:03, 10 November 2013 (UTC)


 * A projectile's KE doesn't necessary have to stay with a smaller body though. Modifying the OP's original question with some different assumptions, consider a bowling ball rolled down the lane onto and up a ramp the height of which is just enough to convert the ball's KE to PE. As it comes to a stop, it's positioned onto the upper-end of a long lever, which is simply a see-saw that pivots, on which the other end is situated a much larger and heavier ball. Because the arms of the see-saw are unequal, under the bowling ball's weight the long arm drops as this larger ball gets lifted to an equivalent PE a shorter distance at which point it gets dropped onto another ramp, such that it continues on forward down the lane with the energy of the original ball. Now due to conservation of energy we have the OP's conundrum. The short answer is, I think, that the system's momentum is still conserved due to Newton's action reaction principle, because if we allowed the larger ball to be propelled out the back of a ship, it produces more thrust (using the same energy) than had we simply thrown the bowling ball and not transferred its energy to the weight. Photons also don't make for very good propellants. Perhaps we can direct the OP to the relevant articles. -Modocc (talk) 17:27, 10 November 2013 (UTC)


 * Yes, this is actually a special case of impedance mismatch casing energy to reflect back instead of being tranmitted to the desired system, and impedance matching to solve this problem. In case of collisions the mass plays the role of the impedance, in electric circuits you of course have the usual electric impedance. In case of sound waves the impedance is related to the speed of sound. If you connect a transmitter to an antenna with the wrong impedance, the power will be reflected back into the transmitter which can damage the transmitter. In that case, you can still use the same antenna, you just have to put an impedance matching device between the transmitter and the antenna. Count Iblis (talk) 18:10, 10 November 2013 (UTC)


 * The different momentum in this case is explained by a change in the momentum of the lane (and eventually the entire Earth). The idea of the efficacy of different propellants is related to specific impulse.  Photons are actually the best propellants if you count by total energy, but the worst if rest mass is free and you count by the amount "added".  --Tardis (talk) 02:24, 11 November 2013 (UTC)


 * To be clear, in an elastic collision, all the kinetic energy that goes in is preserved somehow in kinetic energy going out. Because kinetic energy and momentum are simultaneously conserved, the usual result is that an elastic collision involves a substantial rebound!  If you shoot your projectile into a block and it sticks, then it gets the feeble momentum in the projectile transferred to the total mass of block and projectile, and the rest of the KE goes into heat, noise, flying shrapnel, etc.  (Well, I guess the shrapnel is elasticity rearing its head; inelastic collisions shouldn't make any shrapnel)  The situation where you levitate the block a huge distance is more like if you had a bouncing bullet continually going between the block and the ground banging to push it up, and at the exact moment of collision (only) you released some kind of clamp on the block so that it was in free fall only for that instantaneous moment (since otherwise its PE turns to KE as it falls) Wnt (talk) 20:23, 10 November 2013 (UTC)

Why did lunar module dock with command module on the Apollo program
After leaving the earth orbit on the way to the moon, the command module performed a 180 degree turn and docked with the lunar module. Why was this necessary ? Why wasnt it launched in the correct configuration ? I cant find an explaination anywhere on the internet. I saw this animation on youtube, but no explaination http://www.youtube.com/watch?v=8VvfTY-tVzI Thankyou — Preceding unsigned comment added by Matboyslim (talk • contribs) 20:32, 10 November 2013 (UTC)
 * The Apollo Command Module was situated forward (above) of the Apollo Service Module. The simplest way to design an egress from the CM was "through the top."  An equally valid question is, "why did the CM have two doors?"  There are an infinite number of possible design configurations; the astronauts could have been seated anywhere during launch; but at an early stage in the program, this design was selected: the astronauts launched in the foremost compartment, and an orbital rendezvous was required.  If you are interested in the very fundamental design tradeoffs that went in to the overall architecture of the Apollo Program, you might enjoy reading NASA's history archive: the Apollo Lunar Surface Journal.  There is a chapter on spacecraft design.  More specifically, Buzz Aldrin wrote his Ph.D. thesis on why an orbital rendezvous was the best design choice for a manned lunar mission.  Nimur (talk) 20:45, 10 November 2013 (UTC)
 * (ec) The CSM was a separate spacecraft, which was designed to operate independently of the LM (as it did in the Apollo 7 and Apollo 8 missions). There was no need for it to launch in a docked configuration.  Perhaps more importantly, launching with the LM docked would have made a mission abort rather more difficult - the CM/CSM would have had to make a 180 degree turn (possibly in the atmosphere) after an abort to get into the correct configuration for re-entry. Tevildo (talk) 20:50, 10 November 2013 (UTC)
 * Ultimately, the design decision was: given the natural differences between the Earth and the moon; and given the realizable technology available to American humans in the 20th century; two spacecraft were required to deal with the distinct terrestrial and extraterrestrial launch and landing requirements. Therefore, those spacecraft would require at least one rendezvous and docking operation.  In Project Apollo, it was decided to use two rendezvous and docking operations.  That mission profile allowed astronauts and ground crew to assure that the rendezvous and docking functioned correctly while still in Earth orbit, and to experiment with that operation on pre-Lunar flights (e.g. during the Gemini Program) instead of waiting until the end of the lunar mission to test it.  Nimur (talk) 21:04, 10 November 2013 (UTC)
 * A minor factual correction - TD&E was performed after TLI (although that was technically still in Earth orbit, the actions necessary to go to the moon had been performed). However, I agree that an abort (or fixing a problem with the docking mechanism, as happened on Apollo 14) was much better at that stage than discovering a problem when the LM returned to the CSM from the lunar surface would be. Tevildo (talk) 21:55, 10 November 2013 (UTC)

Correlation between intelligence and sensitivity to the cold?
In humans, is there any correlation between intelligence and sensitivity to the cold? 86.171.42.209 (talk) 20:42, 10 November 2013 (UTC)


 * That's an interesting question. What makes you think that there might be?  It's such an unlikely connection that I doubt whether anyone has done any research on it.  There is certainly a correlation between age and sensitivity to the cold, and I'm beginning to wonder whether intelligence decreases with age (especially in my own brain), but remember that Correlation does not imply causation.    D b f i r s   20:53, 10 November 2013 (UTC)


 * I've spent time in both warm and cold climates, and it's really a matter of acclimation to a given area. ←Baseball Bugs What's up, Doc? carrots→ 20:59, 10 November 2013 (UTC)
 * I have noticed that there does seem to be some correlation between intelligence and sensitivity to various things like that. Purely personal anecdotal though. Dmcq (talk) 00:05, 11 November 2013 (UTC)


 * I'm a Mensan and I thrive in cold conditions. Plasmic Physics (talk) 00:14, 11 November 2013 (UTC)


 * Probably due to our reduced body hair.-- Auric    talk  00:25, 11 November 2013 (UTC)
 * Reading around there does seem to be a link between autism and sensitivity to touch and cold and various things like that, and in particular it is a common complaint of those with Asperger's. I guess that might explain my feeling that there is a correlation with intelligence. Dmcq (talk) 00:33, 11 November 2013 (UTC)
 * And by correlation I don't mean that all or even most of one corresponds with the other. I'm simply saying in a statistical sense. Dmcq (talk) 00:40, 11 November 2013 (UTC)


 * What a coincidence, not only am I Mensan, who thrives in cold conditions, I'm also an Aspie. Plasmic Physics (talk) 00:53, 11 November 2013 (UTC)
 * The section in the article Asperger syndrome seems to indicate the subject has been been studied a bit but there is no general agreement on it. Dmcq (talk) 01:09, 11 November 2013 (UTC)


 * Are we talking about cold climates like the arctic vs. tropical, or like living in the basement? There are things that people can naturally adapt such as altitude changes will change red blood cell volume, whence the acclimatisation phase of mountaineering summit attempts like Mt. Everest as well as seasonal blood vessel changes -> people take coats off in the spring at lower temps than they put them on in the fall because the amount of blood vessels at the skin surface change to accommodate the need to radiate heat.  But I believe Einstein had a wardrobe that consisted of multiple sets of identical clothes so he wouldn't have to clutter his brain with frivolous choices.  Therefore, I'm going to say a moderate, unchanging climate without appreciable seasons is best so that coats, sweaters, shorts or pants decision are never necessary.   --DHeyward (talk) 07:07, 11 November 2013 (UTC)
 * I was thinking that under this premise, the Sherpas and the Inuits must be the most intelligent peoples on earth. ←Baseball Bugs What's up, Doc? carrots→ 13:24, 11 November 2013 (UTC)
 * Have another go at reading the query. Dmcq (talk) 13:44, 11 November 2013 (UTC)
 * The OP asked "is there any correlation between intelligence and sensitivity to the cold." Have a go at explaining precisely what the OP meant. ←Baseball Bugs What's up, Doc? carrots→ 15:35, 11 November 2013 (UTC)
 * I'm not aware of one in humans but there is a correlation more directly between intelligence and temperature in Trolls. Equisetum (talk &#124; contributions) 10:31, 12 November 2013 (UTC)


 * There do appear to be links between various psychological states and temperature (specifically aggression), this could bias one's viewpoint to a certain degree- I'm not suggesting there is an actual link with intelligence. At any rate, see, , , , , , , and if interested.Phoenixia1177 (talk) 10:43, 12 November 2013 (UTC)


 * Sorry, I just reread your question; obviously, none of the above is really that applicable, still, it's somewhat related, so it may be of interest.Phoenixia1177 (talk) 11:01, 12 November 2013 (UTC)

medical condition. Brokers affasier
want to know if this is a correct medical problem.not sure if it is spelt correctly — Preceding unsigned comment added by 5.69.167.5 (talk) 21:08, 10 November 2013 (UTC)


 * There's an apostrophe missing in "broker's". μηδείς (talk) 21:21, 10 November 2013 (UTC)


 * The correct condition is "Broca's aphasia", which I see on editing Medeis has also linked, in a less obvious way. - Nunh-huh 21:35, 10 November 2013 (UTC)

Occupational precautions regarding chemotherapy
What does the "Occupational precautions" section of Chemotherapy say? Does it simply say that medical personnel in contact with chemo patients have to be careful lest they end up getting small amounts of the drugs themselves? The wording is complex and hard to follow (I've re-read it several times), and I don't at all understand the ramifications of the first half of the second sentence. Nyttend (talk) 21:48, 10 November 2013 (UTC)
 * That section of our article contains verbatim excerpts from this CDC website. You have paraphrased it pretty well.  Chemotherapy drugs are potentially hazardous.  People who handle the drugs need to be careful, avoid direct exposure, and avoid long-term indirect exposure.  According to the CDC, exposure to certain anti-cancer chemotherapy drugs can cause everything from skin rashes to causing cancer in healthy people.  Antineoplastic drugs are very potent chemicals.
 * In this instance, I use the phrase "cause cancer" because the CDC expressly states that certain antineoplastic drugs are "known carcinogens." We should be careful to distinguish "known carcinogens" from entities that are suspected to increase risk, or are correlated to cancer incidence in lab studies.
 * We should also probably re-write the section of this article. Nimur (talk) 21:58, 10 November 2013 (UTC)


 * Agreed, and what you just wrote above is perfectly clear, so we should change it to say something like that. StuRat (talk) 22:28, 10 November 2013 (UTC)


 * It was fascinating for me to read this question and its answers, and to look at the CDC material. There are 2 kinds of hospital here in Australia - public and private.  Public hospitals are run by the Government and accept "public" patients - that is the cost is carried by the Government.  The patients pay nothing.  Private hospitals are run by for-profit companies, benelovent foundations, and churches and charge the patients a multitude of fees, which are mostly covered by medical insurance.  Public hospitals also accept private patients - that is patients who pay much the same fee as they would in a private hospital, and in return get to choose their doctor(s), avoid waiting in queues and get extra drugs regarded as beneficial but non-essential.  When my wife had her first breast cancer, she had chemo as a private patient in a public hospital.  The chemo ward nurses wore standard uniforms, and handled syringes, intravenous lines, etc in the normal way.  When she had cancer again in the other breast, she opted for a private hopital.  The difference in care was very noticeable.  One of the differences that stunned us though was that the private hospital chemo nurses, when they went to administer a chemo agent (eg inject it or connect it up to the intravenous drip) they put on, over their standard uniform, a face mask much like the mask that metal worker use to prevent metal filings from entering eyes, nose, etc) a sort of neck-to-ankle apron made of plastic, and gloves. I asked "whats all this?" and the nurse explained that it was standard mandatory safety precautions for her - contact of her eyes, mouth, or even skin with any leak or splash would be regarded as serious.  Each time a nurse went from one patient to another, she took off all the safety gear, threw it in a bin, washed her hands, and put new safety gear on.  We never saw any of this in the public hospital. 124.178.135.228 (talk) 01:55, 11 November 2013 (UTC)


 * That seems like an over-reaction, to me. I'd also guess that such gear causes more harm than good, due to obscuring the nurse's vision and having her poke herself accidentally with the needle.  This is why most soldiers don't wear full body armor, as the lack of mobility and inability to see presents more danger than the protection afforded by the armor.  StuRat (talk) 02:04, 12 November 2013 (UTC)


 * As to whether it is an overkill, I'm not qualified to say. However, given that that this particular hopital is run by a for-profit company, it is unlikely that they would incur costs not necessary. What I can say is that the nurses' vision would be unaffected by the protective mask worn.  I've worn similar masks when doing metalwork, and vision is just not a problem.  Also, a nurse accidentally poking herself with a needle is extremely unlikely.  What is possible, is that the nurse though a muscle spasm might accidentally push the plunger causing some of the stuff being squirted out, or while working on the drip or intravenous administration pump, accidentally cause a line break, or operate the taps in the wrong sequence, either of which could possibly result in some chemo discharged. 120.145.90.77 (talk) 11:10, 12 November 2013 (UTC)


 * However, the economics from the POV of the company include the risk of lawsuits and, if it's a union shop, the union rules, both of which can lead to behaviour which doesn't make economic sense alone. StuRat (talk) 17:47, 12 November 2013 (UTC)
 * All nurses here are members of their union - that applies to both public and private hospitals. The union is mostly focussed on improving pay for nurses working in public hospitals.  Lawsuit risk may well be a greater factor for private hospitals, however that will only be the case if there is a real ie case-demonstrated risk to the nurse.  In Australia, an isolated one-of-a-kind accident is unlikely to pprovide success at lawsuit if the employer can demonstrate their training and gear is industry standard.  Since public hospitals don't use the protective gear, a smart lawyer retained by the hospital could probably get the suit denied on that basis, unless the risk is real.  See post by RmHermen below. 120.145.90.77 (talk) 00:18, 13 November 2013 (UTC)


 * Also, even if it was on net value, I'd bet the money spent on such equipment could improve safety more if spent elsewhere. StuRat (talk) 02:04, 12 November 2013 (UTC)
 * Here is a link describing U.S. practices which seem very similar to those in the private hospital that you saw. Rmhermen (talk) 18:37, 12 November 2013 (UTC)

Unidentified goose (Orange County, CA)
I saw this odd-looking goose at a park in Orange County, California. It's about the size of an Egyptian Goose, and was associating with a gaggle of them. What species/breed is it? 69.111.17.141 (talk) 23:40, 10 November 2013 (UTC)


 * My browser gives a warning on visiting that site. μηδείς (talk) 23:46, 10 November 2013 (UTC)


 * Darn, sorry about that. It should be perfectly safe. But in case there's a problem with dropbox, I'll rehost the picture here. 69.111.17.141 (talk) 00:06, 11 November 2013 (UTC)
 * Thanks for rehosting that. If you search for "grey goose" (you have to use advanced search to exclude "vodka") you will see plenty of grey geese on google images.  Indeed, geese of the genus Anser are called the grey geese.  But they all seem to have orange bills, not black ones.  This may be an example of partial melanism.  I suggest going to WikiProject Birds if you don't get a more . . . black-and-white answer . . . here. μηδείς (talk) 01:16, 11 November 2013 (UTC)


 * Looks like the Snow Goose, or at least the one pictured here: . StuRat (talk) 01:10, 11 November 2013 (UTC)


 * Thank you for the feedback-- upon consulting a few different bird guides, I think what I have is an immature Snow Goose. 69.111.17.141 (talk) 01:30, 11 November 2013 (UTC)

Chronic effects of nerve agent exposure - why?
Why are the effects of nerve agent exposure long-lasting and cumulative, when nerve agents act solely by inactivating acetylcholinesterase, and therefore normal transmission of nerve impulses can resume as soon as the inactivated acetylcholinesterase is replaced? Whoop whoop pull up Bitching Betty 23:47, 10 November 2013 (UTC)
 * Can you give a source for this assumption? Which nerve agent(s)? μηδείς (talk) 23:50, 10 November 2013 (UTC)


 * I suppose (although I'm guessing) that it's not the production of the acetylcholinesterase or the acetylcholinesterase itself that's being "inactivated". It's probably blocking whatever the next step in the biochemical pathway is - and thereby preventing the acetylcholinesterase from working - even though there is plenty of the stuff in the body.  If that's true, then it wouldn't matter that fresh acetylcholinesterase is being produced.  But as I said, this is only a guess. SteveBaker (talk) 00:43, 11 November 2013 (UTC)


 * The organophosphates inhibit acetylcholinesterase, which makes the signal from acetylcholine last longer. According to, these somehow lead to excitotoxicity, which leads to apoptosis.  There is a lot left unclear in that "somehow", both in the paper and its sources I think; I haven't looked into it deeply but there may be some important biology undiscovered there.  In principle though, we can see that more signalling can do that.  The link I give even specifies some compounds that can interfere with the process. Wnt (talk) 02:40, 11 November 2013 (UTC)


 * Guessing is the problem here. [deleted suggested answer]  This also sounds like a homework or test question. μηδείς (talk) 02:45, 11 November 2013 (UTC)


 * It might be, and then it might not be. I think we should give the OP the benefit of the doubt in this case. 24.23.196.85 (talk) 07:19, 11 November 2013 (UTC)
 * That's interesting it means that medicines to protect from damage due to strokes or epilepsy for instance might help as well as ones to block acetylcholine. I guess the ones looking at protecting from nerve gases have tried all sorts of things like that though. Dmcq (talk) 14:09, 11 November 2013 (UTC)