Wikipedia:Reference desk/Archives/Science/2010 June 23

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June 23[edit]

Dingman mouth gag[edit]

Good people; I am doing a bit of research on a surgical tool used in cleft palate surgery. The Dingman Mouth Gag is used by plastic surgeons to hold the jaw open, repress the tonque, and spead the cheeks for the surgeon to work on the roof of a patient's mouth. I would like to read an article on the history and development of this device. My interest lies in how it might be improved upon slightly.

Thank you, Rick Waltonsmith —Preceding unsigned comment added by Waltosmith (talkcontribs) 00:23, 23 June 2010 (UTC)

What about the current device makes it in need of improvement? When performing surgery in the oral cavity, a number of anatomical regions must be properly retracted (lips/cheeks, tongue), access must be appropriate (and so mouth props + ratchets come into play) and sufficient lighting and suction must be employed to facilitate visualization of the surgical field. While all of these things might not be necessarily employed simultaneously for the full duration of the procedure, cleft palate surgery is one of those surgeries in which a) occlusion of the teeth must not be checked, and so closing of the jaws is unnecessary during the surgical procedure and b) the surgery is of a type and duration such that patients are put under general anesthesia (or at least moderate or deep sedation). The latter offers one greater breadth of tools that may be used that would normally not be tolerated by the awake patient. From what I can see from a google search of the device you mention, it seems that it may be very well suited for lip/cheek and tongue retraction, and in a surgical operatory with adequate lighting and suctioning devices, what else can one expect from your improved device? It would have to be significant enough for all the hospitals to throw out their old Dingman and purchase the Waltonsmith-modified Dingman, and for over $1000USD, it had better be worth their time, effort and expense to follow through. DRosenbach (Talk | Contribs) 01:57, 23 June 2010 (UTC)
No offence but if everyone was such a cynic, no one would ever invent or improve anything! And even if the OP can't improve on it, the information he seeks might lead him to this discovery on his own, which would still be a worth while endeavor IMHO. However I will grant that only someone intimately familiar with the device and its use, which the OP is eveidently not, will likely be in a position to improve on it. Vespine (talk) 00:36, 24 June 2010 (UTC)
No offence either but the kind of critical realism that DRosenbach offers is exactly what can help someone such as the OP and your claim that it would prevent all future inventions is ridiculous. Cuddlyable3 (talk) 12:54, 24 June 2010 (UTC)

Alkyd Resin Paint[edit]

what is Alkyd Resin Paint what type of resin do they use ? do they use formaldehyde resin ? —Preceding unsigned comment added by Alexsmith44 (talkcontribs) 01:58, 23 June 2010 (UTC)

Alkyd resins are derived from polyols and dicarboxylic acids or fatty acids by esterification, and are a completely different type of resin from the phenol-formaldehyde resins such as Bakelite. Clear skies to you 67.170.215.166 (talk) 02:56, 23 June 2010 (UTC)

Temperature of water in Kettle[edit]

I was wondering how the temperature of the water in a kettle changes over the course of its boiling. Unfortunately I cannot find values on the internet. Can someone give me these values?

Thanks, 110.174.151.109 (talk) 06:28, 23 June 2010 (UTC)

Doesn't it stay at ~100 Celsius until it's all boiled away?... --mboverload@ 06:47, 23 June 2010 (UTC)

I mean, for example 20 seconds from the time the kettle is turned on the water temp is (just guessing) 50C or something like that. 40 seconds is 60C or something. 110.174.151.109 (talk) 09:56, 23 June 2010 (UTC)

It'll depend on how much water you've got (more water takes longer), where you are (mains power in some countries is a lot weaker than it is in other countries, resulting in water taking twice as long or more to boil), and no doubt, the design of the kettle. Vimescarrot (talk) 11:34, 23 June 2010 (UTC)
(ec) The water temperature will not be uniform across the whole volume of the kettle or whichever item you use to store the water. The temperature will be rising first in the bottom section (assuming a kettle placed on a stove), and only then further up. Now, taking this further - boiling will be setting in quite quickly for tiny amounts of water adjacent to the bottom of the kettle, but the bottom will at the same time be kept cooler by all the colder water lying further up.
Now that we know this, we can discard this for simplicity and use mean temperature values for the entire volume of the water as physics classes in secondary schools assume. The (mean) temperature of the volume of the water will be rising steadily and (I guess) arithmetically until the boiling point. The ratio of temperature increase depends on the amount of water, heat transfer capacity of the kettle (material the kettle is made of; say a stone kettle will take longer to boil than a metal one), energy (right?) applied to raise the temperature (i. e. larger flame vs smaller flame), ambient temperature, ambient air pressure (water will not reach 100 degrees C at Mount Everest). It's not as simple as You suggest, you have to know your settings precisely to be able to tell the exact (mean) temperature of the volume of water at any given time.
After all this theory, it was enough for me to type "water boiling curve" into Google to find this. Hope I was helpful. --Ouro (blah blah) 11:44, 23 June 2010 (UTC)
It won't be entirely linear. Temperature transfer depends (quite strongly - by the fourth power, if memory serves) on the difference in temperature, so the transfer will tend to slow down as the water heats up and gets closer to the temperature of the heating element. I'm not sure how hot the elements typically get in kettles and how that temperature varies as the water temperature changes, so I'm not sure how significant a factor it will be. --14:23, 23 June 2010 (UTC)
Hence my I guess in the brackets. That was the part I was unsure of most. Seems logical what You write, though. --Ouro (blah blah) 14:58, 23 June 2010 (UTC)
If I recall correctly, the heat-transfer rate by conduction is linear in the difference in temperature. I suspect that the unsigned contributor is thinking of the black-body law, which is about the rate at which heat radiates rather than conducts. --Trovatore (talk) 21:19, 23 June 2010 (UTC)

Photon exists? or just a Concept?[edit]

Hi, I would like to know if photon really exists or is just a concept?--Capim Dourado (talk) 06:56, 23 June 2010 (UTC)

Yes, it really exists (inasmuch as anything "really exists").--Shantavira|feed me 07:33, 23 June 2010 (UTC)
See Virtual particle. Ariel. (talk) 07:59, 23 June 2010 (UTC)
I'm just curious. Where did that idea that photons might not really exist come from? Can you give us an example of something that only exists as a concept so we can better understan the back ground of your question? Dauto (talk) 17:41, 23 June 2010 (UTC)
Maybe he was wondering whether it was a fictional particle, like a phonon. There are concepts that are 'fictional', e.g. centrifugal force. John Riemann Soong (talk) 18:48, 23 June 2010 (UTC)
Centrifugal force is not "fictional" - that's nonsense put out by high school math/physics teachers. See this for a coherent explanation. ;-) SteveBaker (talk) 21:58, 23 June 2010 (UTC)
There's a difference between "fictional" and "fictitious". Centrifugal force is not fictional in that it is a measurable phenomenon which actually exists. It is, however a fictitious force, as it arises not from fundamental interactions per se, but due to a particular way of looking at the system. Similarly, one could perhaps call phonons "fictitious particles", as they don't arise from clusters of fundamental particles directly, as "traditional" particles like alpha particles do, but rather from looking at the system as a whole in a particular way. To answer the original question, in all theories of physics I've heard of, photons are considered real, non-fictitious particles, or at least as real and non-fictitious as alpha particles and billiard balls. BTW a web comic, even one as cool as xkcd, doesn't really count as a reliable source. -- 174.24.195.56 (talk) 03:42, 24 June 2010 (UTC)
Phonons are not fictional either. They are as real as a particle can be. Individual phonons have been experimentally produced and detected. It doesn't get more real than that. Dauto (talk) 00:32, 24 June 2010 (UTC)
I agree with the above answers however I don't think the question is as ridiculous as some of the answers seem to suggest, for someone who's not familiar with particle physics anyway. Higgs Boson is an example of a particle which possibly does not exist. Standard model is a good article relevant to this question. Vespine (talk) 03:43, 24 June 2010 (UTC)
It's important to keep in mind that answers like "as real as an alpha particle" or "as real as a particle can be" is not necessarily quite as real as most observers would expect. It is quite difficult to reconcile quantum mechanics with realism. See the article on the two-slit experiment for a first indication of why someone might want to consider particles to be fictional — you get the interference pattern if both slits are open, but you don't if you close one of them off, even if the particles are released slowly enough that only one should be going through at a time. So which slit did the particle go through, if there really was a particle?
More sophisticated arguments involving the Bell inequality, which is experimentally confirmed (e.g. by the Aspect experiment), place actual hard limits on certain sorts of realistic interpretations of quantum mechanics.
That's not to say there can't be realistic accounts, but they all have other difficulties that most people are also hesitant to accept, such as backwards causality, or some sort of superdeterminism that is very hard to distinguish from "God decided that the experiments would all come out that way". --Trovatore (talk) 03:59, 24 June 2010 (UTC)
A little self-correction here: What's confirmed experimentally is the violation of the Bell inequality, not the Bell inequality itself. I had forgotten that detail. --Trovatore (talk) 05:07, 24 June 2010 (UTC)
Part of the problem is that we can only conceive of the particle realm in terms that our minds can handle. so, put technically, some phenomenon surely exist which produces the effect that we have tried to capture in the concept 'photon'; but whether our 'photon' conception is actually anything close to a good description of that phenomenon is an entirely different question. --Ludwigs2 04:06, 24 June 2010 (UTC)
I would be careful in this context with words like phenomenon, which someone might think you're using in its technical philosophical sense. Actually I'm not quite sure you aren't, though I don't think you are, because it wouldn't make much sense as far as I can see. --Trovatore (talk) 04:08, 24 June 2010 (UTC)

Suppose that starting from the Theory of Everything you can do approximate calculations by introducing fictitious fields described by a fictitious Lagrangian that happens to be the Standard Model Lagrangian. Note that in any real process, the external lines in a Feynman diagrams start and end at sources. Just like the internal lines representing virtual particles or ghosts are not real, we can't be sure if the external lines represents things that are real. Count Iblis (talk) 14:58, 24 June 2010 (UTC)

Well, as you're reading this, something is affecting your retinas to produce a discernable image. Generally, we call these things photons. You don't have to though. It's certainly something though, so they are certainly real. Vranak (talk) 18:18, 24 June 2010 (UTC)
Sorry but I think the above is very poor reasoning. Easy to say with hindsight, but by the very same reasoning, "cold" and "heat" were once thought to "real" too. Vespine (talk) 00:00, 25 June 2010 (UTC)
Well, they do refer to real phenomena. And what shall we call those phenomena? How about, photons, heat, cold, etc. Vranak (talk) 04:39, 25 June 2010 (UTC)
Ok but cold existing as a "phenomena" is a long shot from it existing as some sort of fluid called frigoric. Darkness also exists as a phenomena. That's more like the distinction I think the OP was referring to. Vespine (talk) 06:23, 25 June 2010 (UTC)
There is no such thing as "a phenomena". --Trovatore (talk) 08:52, 25 June 2010 (UTC)
Ontology is a slippery subject. Which of the following "really exist", and which are "just a concept": gravity, temperature, energy, democracy, pain, the colour blue, the sky, the number 17, aleph-null, Robin Hood, Homer Simpson, the Invisible Pink Unicorn, next week's lottery winner, the first female President of the United States ? Nevertheless, in any system of shades of reality photons will be placed near the "really real" end of the spectrum. Gandalf61 (talk) 09:38, 25 June 2010 (UTC)

Probability in Quantum Mechanics[edit]

Why do we assign probabilities to states in quantum mechanics? Is it because we presently lack the knowledge to determine the state of an elementary particle, and can only assign statistical probabilities from empirical observations? Or has it been shown that it is physically impossible to know for certain the state of a particle? —Preceding unsigned comment added by 220.253.96.217 (talk) 07:29, 23 June 2010 (UTC)

See uncertainty principle and Heisenberg, for starters. The short answer is: with a "God's-eye" microscope (so to speak), it would still be impossible to specify BOTH the position and velocity of, say, an electron; the more exact you are for one, the less so for the other. It's a fundamental property, not a product of technological limitations. 63.17.50.124 (talk) 08:12, 23 June 2010 (UTC)
Also take a look at the Quantum Zeno effect. ~AH1(TCU) 15:04, 23 June 2010 (UTC)
While the answers above are essentially correct, they miss the mark. In fact, a state can be precisely determined in quantum mechanics. For instance the state of an electron in a hydrogen atom is precisely determined by four quatum numbers. Not only that but the evolution of a quantum state is described by an unitary quantum operator which makes it completely deterministic! The problem arises when you make the wrong kind of question such as "What's the precise position and momentum of that electron?" Thap happens because of the wavy nature of the quantum state. Dauto (talk) 21:50, 23 June 2010 (UTC)

Cr-V[edit]

An alloy is composed of vanadium (V) and Chromium (Cr), how the two can be separated from the metal alloy of it? This alloy is particularly weak magnetic and suction are Iron and Iron powder. I know the nature of the two metals are very similar, separating it from the alloy is probably a bit difficult!--אנונימי גבר (talk) 08:00, 23 June 2010 (UTC)

Very difficult unless you do a chemical reaction to dissolve the alloy, (or vaporise the alloy).77.86.123.157 (talk) 13:11, 23 June 2010 (UTC)
Were you interested in a chemical method? 77.86.123.157 (talk) 13:16, 23 June 2010 (UTC)

>I give a solution of Sodium Hypochloride and Sodium hydroxyde, and the effect of Chromium alloy - Vanadium is obtained a brown black precipitate, which I think may be Chromium (III, II) oxide. But what is it with you?--אנונימי גבר (talk) 10:23, 25 June 2010 (UTC)

I personally think this reaction is due to the Sodium Hypochloride liberated oxygen atoms that make up the alloy oxidized

Zombies[edit]

Are zombies real ??? —Preceding unsigned comment added by Galaxyboy93 (talkcontribs) 08:51, 23 June 2010 (UTC)

No. Someguy1221 (talk) 09:03, 23 June 2010 (UTC)
But see Tetrodotoxin. Ariel. (talk) 09:50, 23 June 2010 (UTC)

you are right ariel, plus see Clairvius Narcisse

Not according to our articles. Tetrodotoxin specifically says that the symptoms don't match those of voodoo-zombieism - and the Clairvius Narcisse article says that the story has "met with some criticism" from the scientific community. That's a very polite way of putting it...the truth is that neither of these things are remotely anything to do with zombies - which are pure fiction. SteveBaker (talk) 21:56, 23 June 2010 (UTC)
Don't forget about catatonic state, depersonalization and vegetative state. ~AH1(TCU) 15:02, 23 June 2010 (UTC)
BRAINS --Ludwigs2 04:07, 24 June 2010 (UTC)
Yes, Galaxyboy93, there is a zombie. He exists as certainly as mindless wandering with outstretched arms and grey skin marked by enormous bloody gashes and brain-eating while being blasted with a shotgun but not being killed exist, and you know that they abound and give to your life its highest beauty and joy. Alas! how dreary would be the world if there were no zombies. It would be as dreary as if there were no Galaxyboy93s. 63.17.32.100 (talk) 09:34, 24 June 2010 (UTC)
Zombie computer? Googlemeister (talk) 13:20, 24 June 2010 (UTC)
The Zombie Alert that was prominantly displayed on emergency signs in Austin, Texas last year was easily dealt with by local construction workers armed with nothing more than jack-hammers and chainsaws. Warnings of Nazi Zombies in the area turned out to be an early overreaction and the grass-roots Keep Austin Zombie Free campaign has paid off well and I, personally, have not been even slightly inconvenienced by Zombie invaders since my morning commute in January last year, and evne then, the biggest problem was people blatently ignoring the instructions to "RUN!!!" so clearly displayed on roadside signage, and instead stopping to take photos. SteveBaker (talk) 15:05, 24 June 2010 (UTC)

Bioavailability of iron[edit]

Irn Bru contains ammonium ferric citrate. Is the iron in this accessible for the human body to use? I've had a look at Human iron metabolism and it just confused me on this point. It says "To be absorbed, dietary iron can be absorbed as part of a protein such as heme protein or must be in its ferrous Fe2+ form. A ferric reductase enzyme on the enterocytes' brush border, Dcytb, reduces ferric Fe3+ to Fe2+." Does this mean the body can absorb ferric ions, by converting them to ferrous ions? Does the citrate confuse this? or the ammonium? 86.164.66.4 (talk) 11:09, 23 June 2010 (UTC)

The body can't absorb Fe(II) ions? :S I thought they were water soluble. Plus, citrate can't reduce Fe(III) to Fe(II)? John Riemann Soong (talk) 18:52, 23 June 2010 (UTC)

I don't know: that's why I'm asking. 86.164.66.4 (talk) 19:06, 23 June 2010 (UTC)
This seems to answer your question [1] also here in full - yes citrate prevents the iron being absorbed a bit, but not totally.
Yes ferric iron is absorbed by first converting to ferrous iron.
It seems that ferric reductase is present in the duodenum amongst other places.77.86.123.157 (talk) 00:11, 24 June 2010 (UTC)
Cool, thanks! That's both helpful and interesting :D 86.164.66.4 (talk) 00:17, 24 June 2010 (UTC)
Does this mean Fe(III) ions induce oxidative stress? (I suppose the body wants to reduce Fe(III) in order to prevent unwanted Lewis-acid-catalysed reactions?) John Riemann Soong (talk) 16:06, 24 June 2010 (UTC)

Attracting flies to my fly paper[edit]

I hung up some fly paper to catch flies, but they're not interested in it. I managed to catch one manually, by pressing the paper against it, but that's not the idea! I sprinkled sugar on it, to try to lure them towards it but still, they buzz around the house, mocking me. What ought I to do to make the paper more attractive to these cheeky little flies? --78.148.140.94 (talk) 15:32, 23 June 2010 (UTC)

Flypapers are good for catching those smaller flies that make little zig-zaggy flights around the light in the centre of the room but for those bigger guys who buzz from one room to the other like they've left something somewhere then they are less good. My suggestion is to experiment with positions, like near the entrance where they..er, enter or in a window where the light is more likely to attract them. 86.4.183.90 (talk) 18:21, 23 June 2010 (UTC)
I like the way you write very much, you must be a very nice young woman. 92.230.69.146 (talk) 21:42, 23 June 2010 (UTC)
Is this some sort of in joke? Otherwise this is possibly the creepiest post I've ever read on the ref desk.. If the OP hasn't been scared away for life already I'd like to state that the above unregistered user does not represent the view of Wikipedia or the majority of ref desk regulars.. You may or may not be nice, young and/or a woman however the ref desk regulars would mostly refrain from judging you based on any of those factors.. Well unless you are particularly not nice, then we might. Vespine (talk) 23:16, 23 June 2010 (UTC)
lol... If I was a very nice young woman, then I don't know what I would've made of it, but I'm actually a nice young man, so I find it pretty funny. I like to think of myself as a brilliant combination of feminine and masculine characteristics; a few days ago, I baked some really moist blueberry and strawberry muffins and today, I rendered a garden wall (well, started it, anyway). Sometimes I write like a nice young woman, other times like a cantankerous old man :D goodnight; much love (Oh, I just noticed that my IP has changed! I'm the OP with the pest-control problem!) 92.28.83.178 (talk) 00:20, 24 June 2010 (UTC)
Commercial flypaper is usually yellow which is apparently the most attractive colour for flies. Also hang it up high, an it will be a natural landing space. Instead of sugar you can put prawn paste. This will attract flies as it decomposes. Graeme Bartlett (talk) 06:59, 24 June 2010 (UTC)
Yellow? As I recollect, most fly paper is brownish where I come from, distributed in rolls (picture something like an old 35 mm camera film roll container) and hung from convenient objects, usually in the kitchen by the ceiling lamp. These things seem to be pretty damn effective - my girlfriend's parents use these and there are usually dozens of flies (all sizes, not just the little ones) stuck to them. Creepy. AFAIK, flypaper is meant to be attractive to insects, not just sticky, through smell and/or special chemicals. Experiment with other brands, I suggest. Last year we assaulted our food moths (these guys) with something similar (pieces of specially-coated cardboard stuck to shelves) and I think we got most, if not all, of them, and I do hope to think it was not just coincidence that they wandered onto the paper. We repeated the process until the last sheet was left untouched, which we saw as a sign that the colony was no more. Sorry for the excessive talkativeness. Yes, that WAS a creepy answer up there by 92.230) --Ouro (blah blah) 08:27, 24 June 2010 (UTC)

A type of memory disorder[edit]

Its funny. I'm trying to remember the name of a type of memory disorder, but I can't remember. It sounds sort of odd. It is defined by an occurrence where you are doing something that you do regularly like drive a car, or shoot a basketball, etc; but you feel like it is the first time you have done it. You may well realize this isn't the first time I have ever driven my car, but there is at least a portion of the activity that suddenly feels unfamiliar and new. It sounds similar to the Choking Under Pressure phenomenon, but not related to sports necessarily.Mrdeath5493 (talk) 16:33, 23 June 2010 (UTC)

not really a disorder but sounds like Jamais vu --Digrpat (talk) 17:09, 23 June 2010 (UTC)
That seems to describe it quite well, but I'm not sure it is the term I'm looking for. Maybe you could call it a temporary impairment? I read about it in a medical text in a section about absence seizures. Nevermind. A quick Ctrl+F found that to be exactly it. Thanks, Digrpat.
Mrdeath5493 (talk) 17:33, 23 June 2010 (UTC)

sodium borohydride and hydrogen peroxide[edit]

Thermodynamically I know the reaction is spontaneous; but what about kinetically?

What about sodium perchlorate and sodium borohydride under strongly basic conditions? John Riemann Soong (talk) 18:57, 23 June 2010 (UTC)

First reaction - you might get peroxoborates (mostly stable, but some very unstable)+ hydrogen, rather than reduction of the peroxide, this is what I would expect to be the kinetic product.
note the reactivity of hydrogen peroxide is increased in many reactions by a lewis acid, even a weak one. Thus the reaction of LiBH4 might be different due to Li+ activation (speculation) —Preceding unsigned comment added by 77.86.123.157 (talk) 21:43, 23 June 2010 (UTC)
Second. No reaction in ice cold water. No kinetic pathway I'm aware of. At some temperature a reaction will start - but this would just lead to thermal runaway and destruction of both reagents to the most stable products.
The second is a reaction not to try in the solid phase + heat , or in concentrated solutions, even if it is expected not to react.. unless you take special (ie remote) precautions.
more Searching http://www.google.co.uk/search?q=perchlorate+borohydride+reaction&hl=en&ei=HH0iTMyXNoWi0gTw2Oj4BA&start=20&sa=N shows that perchlorate is a stable counter ion in many borohydride reductions, as far as I'm aware strongly basic conditions reduce the activity of both - so no reaction. 77.86.123.157 (talk) 21:22, 23 June 2010 (UTC)

Delayed death after serious injury[edit]

Why do some people die some time after receiving a serious injury? I would have imagined that if you survived the injury, then your body would start healing and you should not die. Is it due to a build up of toxins that the injured body cannot clear? 92.15.3.0 (talk) 19:55, 23 June 2010 (UTC)

Sometimes it can be toxins. Sometimes it can be internal bleeding. Sometimes it can be organ failure. Sometimes it can be an infection. Googlemeister (talk) 19:58, 23 June 2010 (UTC)
I suppose it depends on the timeline - shock can easily kill someone after they are seriously injured. TheGoodLocust (talk) 20:22, 23 June 2010 (UTC)
Sepsis and/or shock (and, um, septic shock) often play a role in "finishing off" someone who has survived the initial injury. Matt Deres (talk) 20:36, 23 June 2010 (UTC)
Depends on the sort of injury. Blunt force injuries can sometimes appear benign and then the patient may deteriorate due to bleeding. If you have a sharp injury wound and lose a lot of blood, there is no guarantee that you will receive the blood in time to combat the effects of hypovolaemia. As mentioned above, toxins are sometimes unapparent and when they do kick in, it can be too late to start reversing the effects. Sepsis plays a big role in open wound injuries and sometimes the risk of death by infection outweighs the risk of dying from the initial injury. Finally, it should be noted that some injuries are unrepairable. Brain and other nerve injuries are very hit and miss with recovery; some may recover and others may not. In summary, our bodies are amazing and can recover from remarkable injuries, but they're not perfect. Sometimes things appear fine and then other factors come into play and it's too hard to combat them. Regards, --—Cyclonenim | Chat  21:01, 23 June 2010 (UTC)
Oh, I forgot that sometimes after the injury things inside the body will move and cause problems, such as a fat embolism. Googlemeister (talk) 21:15, 23 June 2010 (UTC)
While I can't be sure, in terms of timeline I'm guessing the OP is thinking of the sort of thing where you here of someone e.g. surviving a plane crash or car crash or falling down a cliff or being shot or stabbed or whatever but dying in hospital (not from life support being turned off as the patient is brain dead where in some ways the patient was already dead) a few days, weeks or months later, rather then someone dying a few hours after the injury occured. Nil Einne (talk) 21:21, 23 June 2010 (UTC)

Yes, I was thinking of days weeks or even months later. 92.15.3.0 (talk) 21:53, 23 June 2010 (UTC)

An injury to the head can create an opening which allows leakage of Cerebrospinal fluid fluid into the sinuses. This leakage can continue without symptoms (other than a "runny nose") for months, until bacteria, viruses or fungus make their way into the CSF around the brain and cause Meningitis, which, if not treated promptly, is often fatal. Edison (talk) 22:32, 23 June 2010 (UTC)

I was also thinking of people being treated in hospital. 92.24.191.32 (talk) 22:58, 23 June 2010 (UTC)

I think infection is the most likely explanation of a death that long after an injury. Open wounds, especially burns, are very good ways for infections to get in. If you are in a hospital, then there is always a risk of things like MRSA. --Tango (talk) 23:26, 23 June 2010 (UTC)

I would offer than a reasonably healthy human body has all sorts of mechanisms that can help mitigate immediate death. Only after all options have been exhausted does a human expire. Vranak (talk) 18:17, 24 June 2010 (UTC)

Identify wasp or insect[edit]

Wasp
Wasp
Wasp ? Click to expand

Can anyone identify this wasp (UK) slightly squashed - it's quite red, line spacing is 5mm 6mm. Sf5xeplus (talk) 23:54, 23 June 2010 (UTC)

Looks like a kind of Ichneumon wasp. If you tell us where you saw it (country, area, etc.) it would probably help. Matt Deres (talk) 00:38, 24 June 2010 (UTC)
Found it in England, Kingston upon Hull. (I've still got it if more info is needed, but I'd like to bury it quite soon..).77.86.123.157 (talk) 00:45, 24 June 2010 (UTC)
Could be Ophion sp. Those are found in England, look about right, have large ocelli and short ovipositor. This is just a guess, though, so it's quite likely that I'm dead wrong on this one. There are many ichneumonid species found in UK, and I am unfamiliar with most (I'm not from UK). --Dr Dima (talk) 01:29, 24 June 2010 (UTC)
Thanks - most in commons under Ophioninae look close to me. I'm worried that you decribe the ovipositor as short - it looks absolutely massive to me (3mm) - I hope there's no chance one of these would mistake me for a caterpillar.
Q.? Do they have a sting or not - the thing I think is a sting in the tail is not? Is that right? I read the article
Q. ? Because it has an ovipositor this must be a female then? 77.86.123.157 (talk) 01:56, 24 June 2010 (UTC)
For what I know, Ophion can actually sting a human (most ichneumonids can't). Regarding the ovipositor size, some Ichneumonidae (namely Megarhyssa) sport the longest ones in existence. If you see one, you will be impressed. The ovipositor of Ophion is relatively short for an Ichneumonid. --Dr Dima (talk) 02:29, 24 June 2010 (UTC)
And regarding your last question: yes, sure enough, males lack an ovipositor. --Dr Dima (talk) 02:32, 24 June 2010 (UTC)
ok thanks, that's enough info for me.
Resolved