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April 6[edit]

Diverticulitis questions[edit]

Okay, some of you know me, and I need help. I've got diverticulitis, the fever is down, the pain is almost gone now, and I'm on cipro and metro (generic flagyl). I had it once before, 3 years ago. I've read a lot and listened to my doctors, and I'm confused, frustrated and a little anxious. My preference would be a private conversation with anyone who's comfortable with the topic, but if there are no takers, I'll post a few questions. - Dank (push to talk) 02:43, 6 April 2014 (UTC)[reply]

Sorry Dank, but by policy we are prohibited from giving any form of medical advice or recommendations on the ref desks and on the project in general. The best we can do is to direct you to seek the assistance of a medical professional. Best of luck to you, though. Snow (talk) 02:54, 6 April 2014 (UTC)[reply]

Yes, we can't really hold discussions or give advice. But searching google for diverticulitis support groups or forums finds many hits, like these. My from-experience advice, which I can give you, is that given the morbidity, especially with slipshod treatment, seek out aggressive specialist care. μηδείς (talk) 03:15, 6 April 2014 (UTC)[reply]
- Thanks Medeis, I didn't know about those, that's very helpful. - Dank (push to talk) 03:33, 6 April 2014 (UTC)[reply]

information[edit]

Changes can be coaded as information — Preceding unsigned comment added by Gamts564 (talk • contribs) 03:14, 6 April 2014 (UTC)[reply]

I can't make out a question here, please clarify. StuRat (talk) 03:28, 6 April 2014 (UTC)[reply]

Uk DMAT[edit]

Does the UK have any DMAT teams? DMAT meaning disaster medical assistance team. A team of doctors and nurses, who work on call, to provide emergency care at scenes of incidents. What is it called in the UK? — Preceding unsigned comment added by 90.201.212.79 (talk) 10:46, 6 April 2014 (UTC)[reply]

I don't know if this is the same thing but there are MERITs, medical emergency response incident teams. These are small, 3 or 4 medics. All the best, Rich Farmbrough, 14:29, 6 April 2014 (UTC).[reply]

I'm not sure if it's exactly the sort of thing you're asking about, but in the East of England we have Magpas, which is a charity. AndrewWTaylor (talk) 09:07, 8 April 2014 (UTC)[reply]

USAR[edit]

Do urban search and rescue teams employ structural engineers? 90.201.212.79 (talk) 10:52, 6 April 2014 (UTC)[reply]

Yes -- see Urban Search and Rescue. 24.5.122.13 (talk) 01:19, 7 April 2014 (UTC)[reply]

Rectum[edit]

Is rectum part of anus? Link to my user page when you reply. HYH.124 (talk) 11:31, 6 April 2014 (UTC)[reply]

No, the anus is a sphincter muscle which closes the end of the digestive tract and facilitates controlled waste expulsion. The rectum is a cavity composed of smooth muscle tissue and attached at it lower margin to the anus. Its function is to consolidate faeces by means of peristalsis and moisture absorption. I'm sorry but I don't usually respond to orders from people I don't know who are asking me for information. Richard Avery (talk) 13:18, 6 April 2014 (UTC)[reply]

Here's a ping for you, User:HYH.124. Dismas|^(talk) 02:43, 7 April 2014 (UTC)[reply]

@Dismas: I saw... Isn't that too late? HYH.124 (talk) 11:46, 7 April 2014 (UTC)[reply]

Alfred Russell Wallace quote[edit]

On this site I read this, Even a replay of terrestrial evolution would almost certainly lead to substantially different end-products, a claim first put forcibly by [Alfred Russell] Wallace and echoed many times since. I'd like to find where Wallace said this, or one of the places he said it, so I can quote the original for an essay.

Thank you Adambrowne666 (talk) 12:28, 6 April 2014 (UTC)[reply]

PS I'm ashamed to say this is the first I've heard of Wallace - what a guy!

I think that, given a generic "plant", a rerun of evolution would lead to trees. Given a generic "bird", we would have ducks. (At least they would look like ducks and act like ducks though I'm not entirely sure they'd quack like ducks). Given any mammal, and ants for it to eat, we would eventually have anteaters. Given any animal at all, you'd soon have a worm. Basically, to continue this game, choose any nice popular term for a species that is paraphyletic, and we know that evolution can converge to it. Now whether evolution would converge at any distance further than we know it has converged, that is a harder one to guess, because we don't know how often a species would have taken up a niche and form but been unable because the incumbents were simply too good at it already.

A philosophical digression perhaps worth noting is that the existence of evolutionary convergence tends to refute those who say that the universe is without purposeful design. Because the so many immediately recognizable archetypes exist, which evolution has come to by multiple paths, it seems more accurate to say that they were already "intended" by the laws of logic and physics long "before" the first example lived and breathed. See Theory of Forms. Wnt (talk) 20:40, 6 April 2014 (UTC)[reply]

Using a google search I can't find any quote by him along those lines. The nearest I can find is here where he says "In order to produce a world that should be so precisely adapted in every detail for the orderly development of organic life culminating in man, such a vast and complex universe as that which we know exists around us, may have been absolutely required." Some of his publications are given in our article Alfred Russel Wallace but he was very prolific and it says there were at least 750 publications in total. Richerman (talk) 09:58, 7 April 2014 (UTC)[reply]

Purely negative evidence, but one of the major themes of Stephen Jay Gould's Wonderful Life is precisely the contingency (non-replay-ability) of the history of evolution, and the book contains no reference to such a statement by Wallace. I find it hard to believe that, if Wallace had ("forcibly") expressed such a view, Gould, who was quite familiar with Wallace's writings, would have omitted any mention of it. There's a contact link on the home page of David Darling's site; perhaps you should ask him for a reference. Deor (talk) 13:50, 7 April 2014 (UTC)[reply]

Yes, good point, Deor, and thanks for the contact link - thanks, all, for the leads. Adambrowne666 (talk) 21:43, 7 April 2014 (UTC)[reply]

need info (oxygen content of water)[edit]

Hello I never had chemistry in school but want to know something. If you released oxygen gas in a water solution would it stay suspended for any length of time say one hour and how could you measure the percent of that content? Thanks a paying donor. — Preceding unsigned comment added by 74.130.204.252 (talk) 15:15, 6 April 2014 (UTC)[reply]

Oxygen does not suspend in water, it dissolves. If you bubble oxygen through water, some of it will dissolve. If you can keep the bubbles inside the water long enough, eventually all of it will dissolve. There are a variety of ways of measuring the oxygen content of water. For example, people who own aquariums can buy a "dissolved oxygen meter" that uses an electrochemical probe. Looie496 (talk) 15:38, 6 April 2014 (UTC)[reply]

There is however a limit to how much oxygen can be dissolved in water, depending on the temperature, salinity, etc. As for air bubbles, they will eventually either rise to the surface and pop or dissolve into the water. Smaller bubbles are more likely to stay underwater long enough to dissolve. Agitation, as by wave action, both has the potential to add new bubbles and keep existing bubbles underwater longer, allowing them more time to dissolve. Thus agitated water is likely to contain more dissolved oxygen than stagnant water. The action of microbes and macroscopic life forms also matters, as plants can add oxygen to the water (and remove carbon dioxide) while animals do the reverse. StuRat (talk) 16:44, 6 April 2014 (UTC)[reply]

The actual amount of oxygen that can be dissolved is governed by Henry's law. The Lake Nyos tragedy was a direct result of this law.--Jasper Deng (talk) 07:53, 10 April 2014 (UTC)[reply]

Airplane black box - another question[edit]

I know virtually nothing about how an airplane black box works. If a suicidal or rogue pilot wanted to sabotage (or at least impede) an airplane's search and recovery efforts by causing "harm" to the black box, would that be possible? Is there any way that a pilot (or any person) can disable, disengage, tamper with, or "shut off" the black box? Or is this notion impossible for some reason? Thanks. Joseph A. Spadaro (talk) 15:17, 6 April 2014 (UTC)[reply]

Yes, of course, but I believe that to do it while the plane is flying would take tools capable of cutting through metal. On the ground it would be pretty easy. Looie496 (talk) 15:23, 6 April 2014 (UTC)[reply]

As a practical matter, no. The flight recorder and cockpit voice recorder are located in a crash-resistant shell at the tail of an aircraft, inaccessible to anyone onboard during flight. But "any" way? Sure. Shoot them with a gun, or smash up the cockpit so that the instruments they operate from are non-functional, or set the tail of the airplane on fire, or, or, or. It's not "impossible", but it's a scenario of last resort.

There's also not much reason. Other than the deep-water "ping", the recorders don't do anything to assist in a SAR effort. Assuming a hijacker does something like fly to the secret Nazi moonbase in Antarctica and lands there, the recorders can't be found unless the whole aircraft is found. — Lomn 15:25, 6 April 2014 (UTC)[reply]

Huh? Isn't that a "chicken or egg" scenario? You said that "the recorders can't be found unless the whole aircraft is found". But, isn't the finding of the recorder itself (via its pings) an event that (sometimes) leads to the finding of the aircraft? Can't it work both ways (which is found first, leading to which is found second)? Joseph A. Spadaro (talk) 15:31, 6 April 2014 (UTC)[reply]

The weak ping makes them not much use in finding the airplane very quickly. You have to be almost on top of it to find it anyway. So, it's really only of use during a long recovery process, not for tracking a hijacked airplane while in flight. StuRat (talk) 15:34, 6 April 2014 (UTC)[reply]

Thanks. I am not talking about finding a hijacked plane in mid-flight. My original question is only referring to finding a plane that has crashed (or perhaps, just landed, without a crash). Thanks. Joseph A. Spadaro (talk) 15:37, 6 April 2014 (UTC)[reply]

OK, in that case the still likely need to spot the wreckage to know where to look to get close enough to detect the ping. The black box isn't designed to help them find the crash site, but rather to find the black box and retrieve it's flight info after they've found the crash site. StuRat (talk) 16:03, 6 April 2014 (UTC)[reply]

Some links you may find useful that are to do with Search and rescue, Black box (transportation), Cockpit voice recorder, Flight data recorder and Distress radiobeacon. CambridgeBayWeather (talk) 16:24, 6 April 2014 (UTC)[reply]

Note that the "pinger" only works underwater. It's just a sound that it generates so it can be picked up by a hydrophone/Towed pinger locator. The ELT is a separate piece of equipment. Mr.Z-man 16:34, 6 April 2014 (UTC)[reply]

So, if an airplane crashes on land, there is no "pinging"? Joseph A. Spadaro (talk) 22:39, 6 April 2014 (UTC)[reply]

Correct. If it crashes on land, they can just search through the wreckage manually, and it's generally constrained to a small area. If it crashes in water, it could break apart before it sinks and disperse over a wide area, so trying to find 2 little boxes with remote-controlled submersibles is more difficult. Mr.Z-man 02:36, 7 April 2014 (UTC)[reply]

No, not correct. Just different equipment. The black box will start sonar pings after it comes in contact with salt water. The ELT (which is required on all aircraft, unlike a black box) will emit a radio beacon after a crash. It can also be turned on manually or a voice broadcast on the ELT frequency. The impact force will set it off. In water, however, the radio waves will not be detectable. The ELT's used to operate at 121.5 MHz and 243 MHz but now I believe commercial aircraft have a variety of frequencies for satellite as well as terrestrial location. A crash on land of sufficient force would set off the ELT automatically and if it survives the fire, crash and battery life, will allow rescuers to locate it. I do not know if the black box also has an ELT transmitter. --DHeyward (talk) 06:21, 7 April 2014 (UTC)[reply]

But the ELT is a radio transmitter, not a pinger. Using the same terminology for significantly different things is what causes this confusion in the first place. Mr.Z-man 14:43, 7 April 2014 (UTC)[reply]

It was obvious that the question wasn't about sonar pings when it was stated as a crash on land. There are other types of "pings" so it's incorrect to say that a "ping" is only about underwater sonar pings. In fact, you can open a terminal window on your computer and type "ping localhost" to get a computer ping. See this about MHL satellite pings [1] --DHeyward (talk) 22:24, 7 April 2014 (UTC)[reply]

I have to admit that with the statement the plane "purposefully" avoided Indonesian airspace in order to fly to a location in the South Indian Ocean, I'm beginning to hum Bond music. How hard is it to build an ad hoc private aircraft carrier capable of landing a jet plane anyway? (And throwing the box overboard...) Wnt (talk) 20:44, 6 April 2014 (UTC)[reply]

The longest Supercarrier class built is 333 m long. Laden Boeing 777's usually land on 6 to 10 000 foot runways that don't roll up and down with the waves or have an immediately adjacent Conning tower. 84.209.89.214 (talk) 00:04, 7 April 2014 (UTC)[reply]

It can land on a 6 foot runway ? Awesome ! :-) StuRat (talk) 02:33, 7 April 2014 (UTC) [reply]

If you're coming in at 160 knots while the carrier is going at 159, you can. However, that argument is invalid; why should anyone with that kind of carrier steal a plane? 217.255.182.173 (talk) 06:13, 7 April 2014 (UTC)[reply]

... and even more unlikely that the rogue carrier would find an ocean current of that sort of speed, even with a steady opposing headwind. Dbfirs 06:59, 7 April 2014 (UTC)[reply]

Actually I was thinking of something more like nailing together a few hundred meters of wooden planks, having the plane try to land on it and brake as much as possible before rolling off the end, in order that it could "ditch" without ??? being ripped apart. Then towing the intact plane somewhere. But true, a rocket powered supercarrier standing up on hydrofoils looks a lot more bad-ass carrying the plane back to your secret underwater volcano base. Wnt (talk) 12:58, 7 April 2014 (UTC)[reply]

So... I'm not the only one to think about a James-Bond-esque supervillain with a high-speed carrier?

There might actually be 3 different designs:

Hydrofoil (tried and tested, but a bit on the slow side)
Hovercraft (another proven approach, but a maintenance nightmare — but hey, if you have 100s of minions, go ahead, use them)
Cavitating high-speed hull (don't even know what it's called). Basically the hull forms a bubble, and doesn't touch the water any more, which reduces drag to that of a plane.

And then there's the ekranoplan (it's a redirect, but there's a photo in the ~~artickle~~ article) which is even faster. Not a carrier, but a plane/ship hybrid. IP has a point: Why steal a passenger plane if you have one of these? - ¡Ouch! (^{hurt me} / _{more pain}) 07:16, 8 April 2014 (UTC)[reply]

I demand to be acknowledged as Emperor Penguin and to be paid a ransom in unmarked sardines in return for releasing the hostages unharmed from my undetectable floating Pykrete aerodrome somewhere in Antarctica defended by my helmeted stormtroopers massed at "Deception" island volcano base. Yours insanely Mr. P. 84.209.89.214 (talk) 12:49, 8 April 2014 (UTC)[reply]

In Australia, our military has the Over The Horizon Radar (Jindalee OTHR), which would have detected such fanciful devices. The aircraft track is well within the Jindalee detection range. Hopefully. 120.145.70.125 (talk) 10:34, 8 April 2014 (UTC)[reply]

Could you refresh my memory why it didn't track the plane then? Wnt (talk) 22:13, 8 April 2014 (UTC)[reply]

It jolly well should have. I was attempting humour. The Jindalee OTHR is a notorious example of the Australian military establishment's penchant for buying special customised hardware, at enormous cost, that doesn't work very well. Jindalee cost about $1.8 billion and seems to be a near useless white elephant. Another example is submarines. They bought a fleet of one-of-a-kind subs that are such that only one or 2 can put to sea at any given time due to major breakdowns. Here's the big picture: USA annual defence budget - about $480 billion. Australian annual defence budget - about $110 billion. From that you would expect the Australian defence force to be about a tad less than one quarter of the US defence force in size. US military personel - 1,200,000. Australian military personel - 61,000 (ratio 20:1). US navy vessels - 289; Australian navy vessels 51. US aircraft 4250; Australian aircraft 275 (ratio 15:1). US ICBM's 450. Australian ICBM's - none. It's disgusting. I'm not objecting to our military being tiny compared to the US military. We are a much smaller country population and GDP wise. What I'm objecting to is the very low bang per buck due to waste & incompetence. 120.145.70.125 (talk) 02:39, 9 April 2014 (UTC)[reply]

Australia's defence budget is 23% of the US defence budget? What is your source for that? Dolphin (t) 13:05, 9 April 2014 (UTC)[reply]

Announcements on Australian news media + http://useconomy.about.com/od/usfederalbudget/p/military_budget.htm, Wikipedia articles and other online sources. Note that I have excluded data for the US Coast Guard, for which there is no direct equivalent in Australia, but similar functions are performed by other services, and the accounting for the War in Afganistan - both counties allocate additional funds for that. I've also excluded the US National Guard, which has no counterpart in Australia, which is perhaps a little unfair to Australia, as some functions are performed by the Australian military. The big picture is reasonably correct though: Australia has a huge defence expenditure but little to show for it. It's a disgrace. 121.221.33.67 (talk) 15:33, 9 April 2014 (UTC)[reply]

A more important figure would be, what percentage of the total budget is devoted to military, in US vs. Australia? ←Baseball Bugs ^{What's up, Doc?} carrots→ 15:58, 9 April 2014 (UTC)[reply]

In terms of the necessary taxation causing a contraction of the ecomony, yes. That is a separate issue. But a good measure of economic impact is the military $spend per head of population. USA (318 million people) - its about $1500 per head. For Australia, it's about $4200 per head. I'm more concerned with the waste & incompetence. $4k of my taxes is ok by me if there was something comensurate to show for it - eg submarine availability 80% instead of 15%, an OTHR radar that worked, navy ships that didn't catch fire & be written off due to poor maintenance etc etc... 120.145.12.236 (talk) 17:12, 9 April 2014 (UTC)[reply]

Note that high military spending isn't always bad for the economy, because it can put unemployed people back to work, and thus improve the productivity of the nation. During the military buildup before and during WW2 in the US, for example, the economy dramatically improved, ending the Great Depression there. However, if instead of relying on your own defense industry, you buy everything from abroad, then that's another story. StuRat (talk) 17:34, 9 April 2014 (UTC) [reply]

@121.221, I'm not sure that you're reading the figures correctly. The Australian Minister for Defence says: "In the 2013-14 Budget, the Government has provided $113.1 billion (including $1.4 billion for Operations) to Defence over the Forward Estimates (my emphasis), with the Budget growing from $25.3 billion in 2013-14 to $30.7 billion in 2016-17. This compares to $103.2 billion (including $1.9 billion for operations) in the 2012-13 Budget Forward Estimates."[2] So the annual budget for this year seems to be AUD 25.3 billion. See also the table produced by the Stockholm International Peace Research Institute shown in our List of countries by military expenditures article, viz: United States USD 682.0 billion and Australia USD 26.2 billion. Our List of countries by military expenditures per capita article only has 2009 figures, but puts Australia in 12th position at USD 893 for each taxpayer, compared to the USD 2,141 that the average American had to find. And if it makes you feel any better, spending lots of money on military technology that doesn't work or turns out to be not needed seems to be quite common; see British Aerospace Nimrod AEW3 or Long Endurance Multi-intelligence Vehicle. Alansplodge (talk) 19:27, 9 April 2014 (UTC)[reply]

I work in Defence and can tell you no country spends anywhere near the US. This Wikipedia article shows Australia spends about 1.5% of the US budget. List of countries by military expenditures 122.111.1.154 (talk) 12:54, 10 April 2014 (UTC)[reply]

Being the Cops of the World runs into money. ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:31, 10 April 2014 (UTC)[reply]

Maybe they should do like real cops, and set up speed traps so they can fine people for "revenue enhancement" purposes, of course targeting outsiders, since they can't vote to stop it. StuRat (talk) 16:20, 10 April 2014 (UTC) [reply]

No brain[edit]

I remember reading somewhere about a not too recent medical case regarding an intellectually normal adult person that congenitally lacked most of the brain. If I remember correctly he/she only had the brainstem and all the rest was replaced by water. Has anyone heard of it? --151.41.135.57 (talk) 15:53, 6 April 2014 (UTC)[reply]

Hydrocephalus is the name of the condition, specifically hydrocephalus ex vacuo. The remarkable case I heard of is where the person had essentially normal intelligence, which means the parts of their brain they did have were apparently rewired to take on the functions of the missing parts. StuRat (talk) 15:56, 6 April 2014 (UTC)[reply]

Come on now, we have some leeway on the Ref Desks, but this is beyond the usual level of unsourced/uninformed (and in this case, frankly silly) speculation that sometimes takes roots here. I'd like to use the old chestnut "this isn't brain science" but that's clearly not the case here. Nevertheless, try to appreciate how easily debunked these stories are with the application of the most basic assumptions we can make in neuroscience and appreciate the sentiment one would usually be trying to put across with that idiom. "The parts of their brain they did have were apparently rewired to take on the functions of the missing parts."? We're not talking about one of the temporal lobes taking over function for the other after the latter is damaged or removed; these are vastly different structures with different functions, form and composition. One can no more think without a cerebrum than one could breath without a brainstem and they are not suited to adapting to cover one-another. This is grade-school level brain science. Snow (talk) 22:44, 7 April 2014 (UTC)[reply]

I made no comment on which parts were absent in this case, and therefore which parts took over their function. StuRat (talk) 23:53, 7 April 2014 (UTC)[reply]

No, but without that specification it certainly seems as if you are validating the scenario forwarded by the OP as realistic, and he does specify the presence of only a brainstem. And if you weren't speaking to that particular scenario, then the response doesn't say much, since clearly people are capable of losing some brain tissue from any number of regions while maintaining normal intelligence. But your wording does suggest to me that you were speaking to that or a similarly extreme (and impossible) scenario. Regardless, the Ref Desks are not the place for forwarding speculation based on apocryphal tales; we're meant to be assisting those with questions in finding and contextualizing established answers to their questions, ideally backed by solid sources or at least content from within the project, not pure conjecture based on an old wive's tale. As I said, we get some latitude with regard to WP:V, owing to our unique function within the project, but that doesn't mean we can throw the principle out the window altogether. There's a bit too much of that here at times and it's a liability to these pages since, A) it's likely undermine trust in our responses, collectively, and B) it might start to cause some to question if we are operating in a manner that is consistent with broader wikipedia policy and priorities. In short, we may not have to go through the formality of sourcing every claim we make in answering a question as we would in an article, but we do need to be at least reasonably certain we could provide a reliable source if it came down to it, that those sources would be trusted sources in an article context, and that the claims themselves pass basic empirical rigour. Snow (talk) 00:54, 8 April 2014 (UTC)[reply]

I provided the relevant link to a Wikipedia article, along with the specific variation the OP described. From there they can find all the sources they need. StuRat (talk) 00:57, 8 April 2014 (UTC)[reply]

It's not the mention of that condition or that wikilink that I found inappropriate to this locale, but rather your following statements. Given that he mentioned water, it was reasonable to point him to that information, no doubt; that is a medical condition with firm sourcing. The following speculation (not at all consistent with any medical science), however, is not appropriate as it cannot be verified and the scenario you presented is likely to cause the OP, and possibly others reading it, to think there is some possibility that the story he heard is plausible, which it is not - not even vaguely. This type of extraordinary claim should not be so much as mentioned here as an empirical possibility without verification, which is certainly not found in the article linked to. Snow (talk) 01:16, 8 April 2014 (UTC)[reply]

This paper might interest you[3] Sean.hoyland - talk 16:17, 6 April 2014 (UTC)[reply]

I've encountered this question literally dozens of times, over a span of 25 years. Rather than write out a long answer here, I've placed it on my personal web site so that in future I can just give a pointer to it -- see http://weskaggs.net/?p=2311. Our article on John Lorber is also relevant. Looie496 (talk) 16:26, 6 April 2014 (UTC)[reply]

Well you might like to check out this lady, who was a neighbour of mine in Barnsley and I can tell you she was one sharp cookie! --TammyMoet (talk) 18:08, 6 April 2014 (UTC)[reply]

Unfortunately that case never seems to have been published -- and web pages, as we Wikipedians all know, can't be treated as reliable sources. Looie496 (talk) 21:08, 6 April 2014 (UTC)[reply]

http://www.thepsychologist.org.uk/archive/archive_home.cfm/volumeID_16-editionID_96-ArticleID_583-getfile_getPDF/thepsychologist%5C0703mdia.pdf --TammyMoet (talk) 09:40, 7 April 2014 (UTC)[reply]

That's not a peer-reviewed source, and in any case the conclusions there are pretty conservative. I have no doubt that hydrocephaly can tell us important things about brain plasticity. But there is no acceptable evidence from it that you can have normal intelligence with only a tiny sliver of a brain. Looie496 (talk) 13:29, 7 April 2014 (UTC)[reply]

I think you're thinking of anencephaly. Extreme degeneration from hydrocephalus might work too, but that shouldn't take effect until after a brain has formed. Wnt (talk) 20:50, 6 April 2014 (UTC)[reply]

I've never seen a claim of normal intelligence, or anything resembling it, in anencaphaly. Almost certainly the question relates to the hydrocephaly stuff, which has been permeating the internet for decades. Looie496 (talk) 21:08, 6 April 2014 (UTC)[reply]

D'oh! true, I missed the part about the normal intelligence :) . Could be microcephaly, which can display normal intelligence, but I suppose anencephaly by definition ought not to (though there are some genetic causes that can be associated with either). Wnt (talk) 22:49, 6 April 2014 (UTC)[reply]

Stephen King's Thinner mentions just such a case, but as a background detail [4].--Auric talk 03:26, 7 April 2014 (UTC)[reply]

Good link - trace it back a few steps and you arrive at John Lorber's non peer reviewed book "Is Your Brain Really Necessary?" But the issue is, it's not peer reviewed and our article suggests he might not have read the scans right. Which I should mention reminds me of the famous Terri Schiavo case - when forum participants would look at the brain scan on the right, half would say that "all her brain is gone but a few bits", and the other half would say that there's still a thick layer of cortex and even if there's a real difference in density within that, that doesn't prove it's genuinely gone. I'm not actually an expert in reading brain scans but I'll confess some affinity for the latter position. Wnt (talk) 11:34, 7 April 2014 (UTC)[reply]

I suspect that a part of the misinterpretation here is that if you (as an untrained lay-person) look at a photograph of a brain scan - a simple 2D cross-section through the skull - there are at least three very serious ways in which you might misinterpret what you see:

Suppose, hypothetically, you see a scan where a region about half the diameter of the brain-case is full of water. A naive first guess is "OMG! That person has lost 50% of his/her brain!"...but that's not true. The volume of a sphere is proportional to the cube of the radius - so it's not 50% that's missing, it's only 12.5%. Someone with "half a brain" is going to be in a lot more trouble than a person with 88% of a brain. I'm guessing most people would have no trouble believing that someone with 88% of their brain intact could be quite intelligent.
The person who did the scan probably took numerous cross-sections of the brain. Only one of those 'slices' is presented in the photograph that you are being "wowed" with. Ask yourself: Of all of those slices, which one gets published? Well, it's likely to be the most dramatic one. So if (again, hypothetically), someone had a flattened ellipsoidal void in their brain, we'd be seeing pictures of the largest cross-section through it...it's perfectly possible that the brain appears completely intact in the scans just a half inch higher or lower. By assuming this is a roughly spherical void, you might be grossly over-estimating the lost volume.
The part of the brain that's missing may not be a part that's particularly to do with intelligence. Certainly the limbic system and the cerebellum are generally not considered to be areas responsible for what we'd consider to be "intelligence". On the other hand, a loss of large chunk of cerebrum would be pretty catastrophic.

Taken together, it's easy to imagine seeing an exceedingly alarming brain cross-section and have only a few percent of the brain matter actually being missing - and that could easily come from areas unrelated to intelligence. So perhaps, this kind of thing isn't so surprising after all.

SteveBaker (talk) 20:53, 7 April 2014 (UTC)[reply]

A TV news program, probably 60 Minutes on CBS, ran a story years ago about a high school girl whose brain had been affected by hydrocephalus such that only a half-inch or so of brain tissue was visible in CT scan, next to the skull, but she was very average in her grades. Her gait was affected slightly. Edison (talk) 01:02, 8 April 2014 (UTC)[reply]

As a first approximation say a brain is a sphere four and a half inches in diameter, with volume about 90 cubic inches. If she still has a half inch around the outside that gives sphere of 3 and half inches diameter missing. So she would have (4.5^3-3.5^3)/4.5^3 of the brain remaining which is just over half of it. People can get by with half a brain. Plus the pressure probably enlarged her head a bit so that could easily be a bad underestimate. Dmcq (talk) 12:43, 8 April 2014 (UTC)[reply]

Krubera Cave[edit]

I was reading several of the articles of the various cave systems in the world. How do scientists measure the depth of the caves (e.g. Krubera Cave)? 99.250.118.116 (talk) 18:14, 6 April 2014 (UTC)[reply]

The Wikipedia article about the Krubera Cave in Georgia notes that it is the deepest-known cave in the world and has been explored to a record 2,197 ± 20 metres. The sea floor topography near Arabika has been revealed by a digital bathymetric map that combines depth soundings and high-resolution marine gravity data. The data used to make bathymetric maps typically comes from an echosounder (sonar) mounted beneath or over the side of a boat, "pinging" a beam of sound downward at the seafloor. The amount of time it takes for the sound or light to travel through the water, bounce off the seafloor, and return to the sounder informs the equipment of the distance to the seafloor. 84.209.89.214 (talk) 23:34, 6 April 2014 (UTC)[reply]

Barometric altimeter + depth gauge for the wet bits most likely. --catslash (talk) 00:15, 7 April 2014 (UTC)[reply]

Any cave that is explored generally has a cave survey made, but I have no idea how surveying methods work underwater. shoy (reactions) 12:16, 8 April 2014 (UTC)[reply]

Medical prostration[edit]

According to the "Signs and symptoms" section of Marburg virus disease, patients in the disease's early virus phase experience prostration; the article links to our Prostration article, but that covers "the placement of the body in a reverentially or submissively prone position as a gesture". What's actually meant? Prostration has a hatnote saying to read Hyperthermia for "heat prostration", but I'm not sure whether that's meant, whether they mean that the patient is unable to be in any position except lying down, or something else. Nyttend (talk) 18:40, 6 April 2014 (UTC)[reply]

The word "prostration" in general means lying in a spread-out position.[5] ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:21, 6 April 2014 (UTC)[reply]

See Definition 2 here. As a medical term, it means "exhaustion". Heat prostration is an exact synonym of "heat exhaustion", which is when you become so hot, you can no longer effectively move around, or even support your own weight. --Jayron32 19:43, 6 April 2014 (UTC)[reply]