Wikipedia:Reference desk/Archives/Science/2013 June 2

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June 2[edit]

Why doesn't Wellbutrin and an SSRI used in combination result in similar to the triple reuptake inhibitor cocaine?[edit]

Wellbutrin is a dopamine-norepenephrine reuptake inhibitor, SSRIs inhibit the reuptake of serotonin. Cocaine inhibits the reuptake of all three.

Also, would long-term Wellbutrin /SSRI use increase or decrease the norepinephrine response to a beta-2 agonist at the norepinephrine receptor? 71.2.172.65 (talk) 03:35, 2 June 2013 (UTC)[reply]

It's not as simple as that. One has to factor in pharmacokinetics and differing affinity ratios. Hundreds of compounds have affinity for the SERT, NET and DAT but do not produce the effects of cocaine. In fact, cocaine is a nebulous term because it has vastly different effects depending on if it is taken orally, insufflated, injected or inhaled (see coca tea, crack cocaine). Markr4 (talk) 14:25, 2 June 2013 (UTC)[reply]
It's been some time since I last looked into the mechanism, and alas, I shan't get around to it soon, but it is covered to some degree in the cocaine article which mentions some other things like sodium channel. Speculation from long ago, not an answer: the drug interacts with a lot of different receptors for various neurotransmitters, some of which, AFAIR, work as dimers of protein; it is possible therefore that this drug might bring two different receptors to cross-react that don't normally have a reason to talk to each other... Wnt (talk) 18:10, 2 June 2013 (UTC)[reply]

My tea rots[edit]

I drink herbal tea (that's technically tisane, since no tea leaves are involved) without any sugar or sweeteners added, and no milk/cream either. Normally it doesn't go bad, presumably due to the lack of sugar. However, there is one variety which seems to go bad extremely fast. It goes from clear to foggy, and smells and tastes bad, in a few hours at room temperature. I would like to know why this particular herbal tea spoils rapidly, when others do not.

It's Bigelow "Mint Medley", and here are the ingredients:

Peppermint leaves
Spearmint leaves
Rose hips
Lemon peel
Hibiscus

1) Now, my first thought is that some of those ingredients might have sugar in them, such as the last 3. Can such a tiny amount of sugar make the diff ?

2) Also, the lemon peel might contribute some oil (as might the other ingredients). So, could the oils somehow go rancid in such a short time period ?

I won't buy this particular product again, but would also like to know which ingredients to avoid in the future. For comparison, I also drink an herbal tea which is just peppermint leaves. It spoils too, but takes at least twice as long. And finally, I drink another tea containing cinnamon and many other spices which never seems to spoil at all. So, peppermint seems to be at least part of the problem, but not all of it. StuRat (talk) 04:18, 2 June 2013 (UTC)[reply]

The rose hips contain sugar, and quite a bit. One ounce of dried rose hips contains about 5 or 6 grams of sugar [1]Dollars to donuts, that's the culprit. Dominus Vobisdu (talk) 04:35, 2 June 2013 (UTC)[reply]
Wow, and saturated fat and sodium, too. I guess rose hips are nature's junk food. :-) StuRat (talk) 05:22, 2 June 2013 (UTC)[reply]
Except that they've been touted for years as having a far higher Vitamin C content than just about anything else. -- Jack of Oz [Talk] 05:26, 2 June 2013 (UTC)[reply]
Well, rose hips are fruit, and dried fruit concentrates everything in it. 21 grams of sugar/ounce for dried rose hips compares similarly to the 17 grams/ounce for raisins and the 15 grams/ounce for dried, sulfured apricots. --Jayron32 05:27, 2 June 2013 (UTC)[reply]
That's 21 calories from sugar per ounce, not 21 grams. That's equivalent to about 5 grams. Still plenty of sugar, though. You can make rose hip preserves (like apple butter) without adding any more sugar. Quite nice. Dominus Vobisdu (talk) 05:36, 2 June 2013 (UTC)[reply]
No, your source says 21 grams of sugar. It's not explicit, but the data says: 1 oz.: carb 21, protein 3, fat 1 calories 101. 21+3+1 does not equal 101. 21+3+1 = 25, which makes sense in that 1 oz. = 28 grams, so the other 3 grams are other stuff. 21*4 + 3*4 + 1*9 = 105, which is off a bit, but my guess is there's some rounding errors we're not seeing in their data. Now, technically 21 grams of carbs is not 21 grams of sugar, some of it could be starches or dietary fiber, but even for total carbs, it is roughly the same as other dried fruits cited above. --Jayron32 05:43, 2 June 2013 (UTC)[reply]
Look again. Down on the right, it says 5.67 grams of sugar. Don't know where the 101 calories came from. Possibly a mistake. Dominus Vobisdu (talk) 05:50, 2 June 2013 (UTC)[reply]
AH. Thanks. No the 21 grams was for total carbs. Rose hips have a lot of fiber. And the 5-6 grams of sugar is actually a lot less than other dried fruits then. Based on that I'm not sure it's contributing a whole lot to the total sugar of his tea. How much of the tea is rose hip? 10%? That'd be an extra half a gram of sugar, which is equivalent to a few granules of granulated sugar. More likely that the tea is going "off" in a few hours due to other factors, such as over-oxidation, or as is usually the case, over-steeping. Stu, are you leaving the tea bags in for the whole time? Because long steep times or high steep temperatures will extract different compounds from the tea, and will change the flavor profile greatly. It's not clear hear that "bad" means "bacterial growth" or something else at work. --Jayron32 06:02, 2 June 2013 (UTC)[reply]
I tend to leave the tea bags in for the cinnamon tea, but not for the mint teas, so, according to your theory, the cinnamon tea should go off, not the mint tea. The combo of going cloudy, smelling bad and tasting bad certainly implies bacterial growth to me, but it does seem amazingly fast, I agree, for a tea with no added lipids or sugars. Hence the question. StuRat (talk) 06:21, 3 June 2013 (UTC)[reply]
Why do you make so much at a time, Stu? Why not just make it a cup at a time, as you need it? That way, it'll never get the chance to go off, assuming you keep your ingredients dry and airtight. -- Jack of Oz [Talk] 04:52, 2 June 2013 (UTC)[reply]
I like my tea weak. I only use one tea bag, but this makes about a quart/liter. It takes me a few hours to drink. I don't like having to constantly make more tea, so this suits me fine, as long as it doesn't go off. StuRat (talk) 05:22, 2 June 2013 (UTC)[reply]
If your talking about "a few hours", it's unlikely that bacterial growth is the problem. The turbidity is probably caused by polymerization of pectins from the rose hips and lemon peel. That shouldn't affect the taste or odor much, though. If I were you, I'd slide it under the microscope and check for the presence of bacteria. It may be that some componenent of the tea is SOOOOO saturated with bacterial endospores that a population large enough to spoil the tea within hours is possible. As for oxidation, that's not likely. The vitamin C in the rose hips and the anthocyanins in the hibiscus flowers should provide enough antioxidant power for a few hours, all the more so since the water was degassed while boiling. Dominus Vobisdu (talk) 18:00, 2 June 2013 (UTC)[reply]
Yeah, bacterial growth seems unlikely to me off the cuff. Fastest doubling time isn't going to be faster than 20 minutes, and that's for a bacillus in nutrient broth, well aerated. So 3 hours would be maybe 1000 times the original count, which wouldn't cause visible turbidity. And just herbal tea rather than something like chicken soup would be a lot slower (after all, if you leave a mug of chicken soup out for a few hours, it doesn't turn cloudy, and that's a lot more nutritious); might never even get to turbidity at all, there's really not a lot of nutrient there. And just sitting in a cup, non-aerated would be even slower still. As for the question of waking up spores en masse, I really doubt Bigelow is going to market anything with that degree of contamination. Gzuckier (talk) 02:05, 5 June 2013 (UTC)[reply]
If I may quote you: "Ahem" - that would be "If you're talking ...".  :) -- Jack of Oz [Talk] 21:12, 2 June 2013 (UTC)[reply]
And if I may quote Brother Savatore, "Stupido! Stupido! Penitentiagite! Dominus Vobisdu (talk) 21:16, 2 June 2013 (UTC)[reply]
Ahem. That would be Salvatore.  :) Actually, I was given that book for my birthday last year but I've not had a chance to read it yet. I will now find time. Thanks. -- Jack of Oz [Talk] 21:25, 2 June 2013 (UTC) [reply]
Somebody must really love you! It's a great read. Enjoy! (Hope I spelled everything write that time) Dominus Vobisdu (talk) 21:29, 2 June 2013 (UTC)[reply]

Thanks so far, everyone. It looks like I should avoid rose hips, and maybe peppermint. Are the rest of the ingredients OK, as far as everybody knows (meaning they don't cause rapid spoilage) ? StuRat (talk) 03:32, 5 June 2013 (UTC)[reply]

Not necessarily. It may be specific to this particular product. Again, I'm very skeptical that microbial spoilage is taking place. Even ground beef doesn't go off in a few hours unless it's horribly contaminated, and that's a lot more hospitable to microbes than herbal tea would be, especially with no added sugar. The increase in turbidity does not necessarily indicate microbial growth, and there are other more likely causes. Nor does the change in smell or taste, which could be due to the fact that pleasant volatiles evaporate fast and no longer mask less volatile, less pleasant components.
In short, you'll just have to experiment with different products to find one that remains palatable after a few hours at room temperature. I wouldn't necessarily exclude rosehips or peppermint at this point. Dominus Vobisdu (talk) 08:57, 5 June 2013 (UTC)[reply]

What force binds the cells in multicellular organisms together?[edit]

We know, that atoms in a molecule are bound by covalent bonds, large celestial objects are bound by gravity, particles inside an atom are bound by the strong force, and so on. However, what binds the cells in a multicellular organism together? — Preceding unsigned comment added by 5.15.15.144 (talk) 09:26, 2 June 2013 (UTC)[reply]

see Cell adhesion IBE (talk) 10:01, 2 June 2013 (UTC)[reply]

Midnight sun and bird activity[edit]

I passed through Saint Petersburg, Russia this week and they are just about ready to dive headlong into the White Nights Festival. Seeing the sun at 2300 for the first time is a source of real cognitive dissonance, and as a birdwatcher I wondered about the effect such a long daytime period has on birds? Does the dawn chorus still happen? Are they active all day? Active from 0400 to 0600 and then rest almost the entire "day" ? As I was in the city on business I hadn't time to venture out and make personal observations... The Masked Booby (talk) 11:46, 2 June 2013 (UTC)[reply]

Living in Cambridge Bay you can see active birds 24 hours a day. As to the Dawn chorus (birds), the little buggers are more than happy to keep that going all day as well. The birds include ravens, Snow Buntings, gulls and sparrows in town as well as various geese, shore birds and others listed at List of birds of Nunavut out of town. CambridgeBayWeather (talk) 00:53, 3 June 2013 (UTC)[reply]

Air Conditioning and Global Warming[edit]

This may well be the dumbest thing I've ever done, but a kid at work asked me this and I honestly couldn't provide a reason why this wouldn't work, other than 'common sense'.

If everyone with air conditioning ran their air conditioning for an arbitrary amount of time (say, 24 hours) why would the cold air being produced not affect global warming?--TKK bark ! 12:55, 2 June 2013 (UTC)[reply]

Air conditioning works by transferring heat from one lot of air to another lot of air, meaning the net effect is null. Actually, the waste energy inherent in the process of air conditioning, contributes to global warming. Plasmic Physics (talk) 12:59, 2 June 2013 (UTC)[reply]
The waste energy I'm talking about, is in the thermodynamic sense. Plasmic Physics (talk) 13:01, 2 June 2013 (UTC)[reply]
Ah, okay. I've never actually had an air conditioner so they're a bit of a black box to me haha. Thank you!--TKK bark ! 13:08, 2 June 2013 (UTC)[reply]
Actually most air conditioners are a pale neutral color with vents and buttons on one side, and an aluminum grating on the other, not black. Maybe this is why you have had difficulty tracking one down? μηδείς (talk) 13:45, 2 June 2013 (UTC)[reply]
Black box. It has nothing to do with its colors hahaha, it just means that i know that hot air in -> cold air out but not how its actually done. --TKK bark ! 14:07, 2 June 2013 (UTC)[reply]
You don't need to understand the small details of how devices like air conditioners, refrigerators or any other kind of cooling device works in order to prove that you can't solve the problem this way. All you need is the First law of thermodynamics - which tells you (amongst other things) that energy is always conserved in a closed system. So if you take a completely unknown device and place it in an enclosed, perfectly insulated "black box", then feeding electricity into the box will increase the temperature inside - no matter how the device works. Hence, for an air conditioner or a refrigerator or a peltier device (sometimes used for cooling computer chips) - or for any other known or unknown past, present or future cooling technology, the amount of cooling it does is always going to be less than the amount of waste heat it generates by an amount precisely equal to the amount of electricity it consumes. So any effort whatever to cool the earth with refrigeration is doomed to failure.
If you want to cool the earth, you either have to reduce the amount of sunlight hitting the earth by an amount slightly larger than the amount of energy we're burning from fossil fuels (eg place a large mirror out in space between earth and sun) - or increase the amount of energy radiated out into space by a similar amount (eg by covering large areas of the planet with mirrors).
Sadly, the amount of area that either of those solutions would require is implausibly vast.
There is a second way to increase the amount of energy radiated outwards - and that is to remove CO2 from the atmosphere to make it more transparent in the infra-red wavelengths so that more heat can be radiated away into space...and guess what the experts in the field are asking us to do?
SteveBaker (talk) 13:51, 2 June 2013 (UTC)[reply]

You could think of a reverse heat pump where you cool the atmosphere and inject heat deep below the Earth's surface. If the heat pump is powered by solar, wind or nuclear power, it could work. Count Iblis (talk) 13:36, 2 June 2013 (UTC)[reply]

Not in the long term. No matter how deep you go, adding heat below the surface will gradually increase the amount of heat leaking back up into the atmosphere. SteveBaker (talk) 13:51, 2 June 2013 (UTC)[reply]
Haha! Finally I catch SteveBaker in a mistake, after months of trying! The amount of sunlight you'd need to reflect by increasing planetary albedo actually has nothing to do with the amount of energy obtained from the fossil fuels. There are highly effective greenhouse gases that don't involve energy generation at all - for example, if methane leaks from a natural gas well or the rear end of a cow. The heat generated by the fossil fuels is self-limiting because if the planet is warmer it radiates more energy. Wnt (talk) 17:53, 2 June 2013 (UTC)[reply]
Though it is true that heat pumped below the surface will eventually come back out, if we were looking that far ahead we wouldn't have global warming. :) The real problem is just that the amount of cooling produced by all these air conditioners won't matter much. A 100x100 mile square of Nevada matches the entire U.S. electricity usage [2]; in fact, the waste heat from fuels is estimated at 0.007% of the Earth's energy budget in that article. It's hard for me to extract an actual figure for how much the greenhouse warming increases the energy flow for direct comparison, but consider that CO2 is up 39%. Wnt (talk) 18:03, 2 June 2013 (UTC)[reply]
  • You can't do work with heat in a closed system. The earth serves as a closed system here, given we're talking of global warming. See Maxwell's Demon. μηδείς (talk) 19:42, 3 June 2013 (UTC)[reply]
  • But you can perform work to move heat from the atmosphere to heat the Earth's interior. So, if we take an amount of heat of Q from the atmosphere at temperature T1 = 15 C and we want to dumpt this underground at a few kilometers depth where the temperature is T2 = 70 C, we need to perform an amount of work W and then dump an amount of heat of Q + W at 70 C. The lower limit of W follows tfrom the requirement that the entropy doesn't decrease. The change in entropy is -Q/T1 + (Q+W)/T2 (with T1 and T2 in Kelvins), equating this to zero gives W = (T2/T1 - 1) Q = 0.19 Q. So, Q = 5.24 W. To offset the increased forcing due to our CO2 emissions we would have to use all our present day power generation capacity, so this not a practical solution. Count Iblis (talk) 20:00, 3 June 2013 (UTC)[reply]

Explosive boiling of water in a cooking pan on a stove[edit]

I have observed this happen and I think I know why it happens. I can reproduce the circumstances under which this happens as I'll describe below. But it's still a bit surprising to me that this works, previously I would have thought that you would need to use a microwave with the turntable disabled to make superheated water which will boil explosively when you stir it.

To observe explosive boiling of water, I put 5 liters of water in a big pan, turn the heat on until it boils. Then I turn off the heat for a while (about 15 minutes). Later when it is time to boil the macaroni, I put the heat on for a minute or so until the water boils again. The explosive boiling happens when I put the macaroni in the water. This will happen even if the heat is turned off after the water is boiled for the second time. With the heat off, the water doesn't boil anymore, yet it will boil explosively for 5 to 10 seconds (still with the heat off) after the macaroni is put in the pan. Depending on the amount of macaroni you put in the pan, you can have a violent enough explosion to get water and macaroni ejected from the pan, flying several meters away.

The explosive boiling does not happen when the macaroni is put in the pan when the water is boiled for the first time. When the water boils for the first time, it boils in a different way compared to when it boils the second time. The first time, you see a lot of small bubbles when it boils, while the second time you see a few big bubbles, usually just one huge bubble.

So, what do the Ref Deskers think is the explanation for this phenomena? While I do think the explosive boiling is easy to explain, the reason why the water boils differently the first time isn't very clear to me. Count Iblis (talk) 13:32, 2 June 2013 (UTC)[reply]

In the first boil dissolved gasses are driven off. Those are the small bubbles you see.--Digrpat (talk) 14:08, 2 June 2013 (UTC)[reply]
The term you want here is 'superheating' i believe. You get a similar effect if you microwave a mug of water for four or five minutes and then drop in a tea bag. --TKK bark ! 14:10, 2 June 2013 (UTC)[reply]
Sound to me that you're just observing Nucleate boiling--Aspro (talk) 14:19, 2 June 2013 (UTC)[reply]
I believe Aspro is correct. The phenomenon you can acheive in the microwave is when water raises to slightly above "normal" boiling point without boiling, and then can be "set off" all at once by adding coffee granules or something. What the OP is describing is when water is just below or at boiling temperature, but the pasta gives it far more nucleation points so it boils over. Even throwing in a handfull of salt into water can cause a momentary "boiling over". I also doubt the "flying several meters away" claim. I've cooked quite a bit of macaroni in my time and have ocasionally had it leave the pan, but not flying several meters away. I'd have to see footage of this happening before I believe it. Vespine (talk) 02:31, 4 June 2013 (UTC)[reply]
Yes, the introduction of nucleation points is relevant, but I'm pretty sure that the water in the pan at some depth being at a higher pressure also plays a role here. I don't observe this very violent reaction when I have less than 4 liters of water in the pan. So, what I think is going on is that the second time the water has been boiled and the heat turned off is that the water near the bottom of the pan is at a temperature higher than the boiling point at the surface, because it's under pressure and the local boiling point is higher there. Then if I poor the macaroni in (with the fire off), it will lead to convection induced by the extra nucleation points causing boiling, but this then brings the water at some depth to the surface that is at a higher temperature than the boiling point at the surface, leading to explosive boiling there. Count Iblis (talk) 12:32, 4 June 2013 (UTC)[reply]
If the pot is has a full foot of water in it, that is only approximately ½ a psi of hydraulic pressure differential in total (a pressure cooker works at about 5 psi). Second, The pot gets heated from the bottom and has is a heat conducive surface so the resulting thermal circulation (which continues after the heat source is removed) means the water is not in stratified isothermal layers. So no, that don't compute at all. That you have observed this phenomena only over over four litres indicates that the thermal mass is insufficient below this volume. Mice lose a greater amount of heat percentage-wise than an elephant because of the ratio of skin area to mass. --Aspro (talk)
Other thoughts that could explain the magnitude of this 'explosive' reaction is: macaroni, spaghetti etc., is dry with a low conductivity and low specific heat capacity. So it won't cool the water down much but all the gas it contains will expand according to Boyle's law and add the the nucleate boiling. Perhaps a warning should be added to the cooking instructions: “When cooking more than four liters be sure to wear goggles and get your mom's/wife's permission to mess up the kitchen beforehand ”.--Aspro (talk) 21:19, 4 June 2013 (UTC)[reply]

Cats Shedding Oocyst[edit]

When cats shed oocysts, does that mean the Toxoplasma "leaves" the cats' bodies or does some Toxoplasma stay behind?173.180.7.3 (talk) 10:49, 2 June 2013 (UTC)BeeCier (Question moved from Talk:Toxoplasmosis)[reply]

Toxoplasma can also reproduce asexually (without producing oocysts) in the cat's intestine, so the cat is still infected while shedding oocysts. [3] Danger High voltage! 16:18, 2 June 2013 (UTC)[reply]
There are few things more arcane, mysterious, and underappreciated than the life cycles of parasites, but to my doubtless flawed understanding, the end of oocyst shedding is due to immune reaction rather than some sort of salmon-like die-off after spawning. See [4]. Basically, there are two main kinds of -zoites: the "brady" (slow) variety which encyst in muscle and wait to be eaten by somebody, and the "tachy" (fast) which spreads like wildfire right after infection or in people with AIDS, etc. Unlike in humans, where most of our lives are diploid, in these parasites most of their lives are spent as haploid with the diploids formed only when special differentiation into more-or-less eggs (macrogametes) and more-or-less sperm (microgametes) occur to some of the tachyzoites breeding in the intestine. [5] These are only a fraction of those available, an optional sexual step that can recombine strains if more than one is present, but according to that ref there aren't even mating types, which if true means the same tachyzoite might decide to become male, female, or just keep breeding. (I may well be missing something important about this biology here). Wnt (talk) 17:47, 2 June 2013 (UTC)[reply]

Steering of hot air balloon in horizontal plane[edit]

Is it possible to steer hot air balloon horizontally by directing the burner left or right so that balloon would sway and turn accordingly?--93.174.25.12 (talk) 16:22, 2 June 2013 (UTC)[reply]

You can certainly make a zeppelin which moves around with fans. But with the balloon, I should ask: where does the hot air go? If you're spewing it out into space, sure, you have some very very very crude form of jet propulsion. But if you're directing it up into the bag... what do you suppose happens when the jet pushes against the fabric of the far side? Wnt (talk) 17:22, 2 June 2013 (UTC)[reply]
No you can't. Our hot air balloon article describes how "Some hot air balloons have turning vents, which are side vents that, when opened, cause the balloon to rotate. Such vents are particularly useful for balloons with rectangular baskets, to facilitate aligning the wider side of the basket for landing." As Wnt says above, directing the burner risks setting fire to the envelope. PS Wnt, I think you mean airship rather than Zeppelin which was a specific German type. Alansplodge (talk) 18:30, 2 June 2013 (UTC)[reply]
Oddly, I wasn't even thinking about setting fire to the fabric on the far side when I said that (in theory, it could be something fireproof, though I can't imagine what) - what I had in mind was that the jet of gas pushes against the fabric with just as much propulsive force as can be obtained in the reaction from the fan, leaving you with no net force. Wnt (talk) 14:02, 4 June 2013 (UTC)[reply]
Hot air balloons are usually steered by rising or lowering altitude to an height at which the wind is blowing in the direction you want to go. As you can imagine, this is a difficult skill to master! SteveBaker (talk) 00:29, 3 June 2013 (UTC)[reply]
And there's no guarantee that the wind is going in the desired direction at any altitude you can reach. StuRat (talk) 06:10, 3 June 2013 (UTC)[reply]
Yes, exactly. But there is the possibility of at least some directional control - and balloon contests are often held for precision flying that require pilots to get a feel for the wind direction in various layers of the air - including understanding how wind changes direction to divert around hills and mountains. SteveBaker (talk) 14:16, 3 June 2013 (UTC)[reply]

Biology[edit]

If a cat smells petrol ,what will happen? — Preceding unsigned comment added by Titunsam (talkcontribs) 18:02, 2 June 2013 (UTC)[reply]

I don't know. What do you do when you smell petrol? --Jayron32 18:04, 2 June 2013 (UTC)[reply]
I'm not good at riddles. Plasmic Physics (talk) 22:18, 2 June 2013 (UTC)[reply]
If a human can suffocate from excessive gasoline fumes, presumably a cat could also. ←Baseball Bugs What's up, Doc? carrots→ 22:24, 2 June 2013 (UTC)[reply]
He didn't mention 'excessive' though. Or is that implicit by the detectable odiferous limit of petrol? Plasmic Physics (talk) 22:33, 2 June 2013 (UTC)[reply]
If an organism inhales petrol fumes in a quantity that is not excessive, then nothing is likely to happen. So the OP would have to clarify the question, in order to improve the chances of getting a useful answer. ←Baseball Bugs What's up, Doc? carrots→ 22:44, 2 June 2013 (UTC)[reply]
"Nothing" is a perfectly good answer for the question as it stands. Or maybe "Nothing, followed by the cat nonchalantly wandering off". -- Jack of Oz [Talk] 23:09, 2 June 2013 (UTC)[reply]
Cats dislike some hydrocarbons, such as naphthalene, so the cat may not wander off so nonchalantly, but rather make a hasty retreat. Ideas? Plasmic Physics (talk) 23:31, 2 June 2013 (UTC)[reply]
I had a cat many years ago who decided that climbing inside the engine compartment of a recently used car provided a lovely warm place to sleep on a cold day. My cars in those days were never in great condition (I was a poverty stricken student), so there would definitely have been hydrocarbon smells around. That cat lived to a ripe old age. HiLo48 (talk) 01:10, 3 June 2013 (UTC)[reply]
Interesting, but one incident hardly sets a baseline. What's the general trend among cats? Plasmic Physics (talk) 01:24, 3 June 2013 (UTC)[reply]

Off-topic discussion moved to Talk page -- Scray (talk) 01:05, 3 June 2013 (UTC)[reply]

Scray deleted a link to a discussion of this question and Titunsam's user contributions Special:Contributions/Titunsam showing he's a one-purpose ref desk editor with no other wp history. μηδείς (talk) 01:43, 3 June 2013 (UTC)[reply]

(copied from the talk page by request)
Well, I can tell you that the right to do research to determine how cats smell gasoline (specifically) is the private property of Richard Axel et al.; see http://www.lens.org/lens/patent/US_2002_0064817_A1 . The sensitivity to gasoline odor, but not its desirability, was shown to be heritable in a human study [6] so knowing more about it in the cat might help to identify a candidate gene. Gasoline is one of the specific odors whose detection is severely impaired in Parkinson's disease (PMID 12707068) - I don't know if this is true in a cat model system.
Biology has no respect for vanity. The things it is too embarrassing to talk about, whatever is too trivial to think about - these are exactly the things which, by design, can ultimately kill people or save their lives. Wnt (talk) 22:33, 3 June 2013 (UTC)[reply]

Photo of dead body[edit]

I have a question that refers to the photographs at the following link: Photographs of Ibragim Todashev's corpse. What are the stitches (and scars) that form the "Y"-shape across his chest? Is that what happens at the end of an autopsy (i.e., they stitch the body back up in such a manner, after opening up the chest cavity)? Or is something else going on? Does anyone know? Thanks. Joseph A. Spadaro (talk) 18:17, 2 June 2013 (UTC)[reply]

Yes. It's called a "Y-cut" and is commonly performed during autopsy. See out article on Autopsy for more information. Dominus Vobisdu (talk) 18:24, 2 June 2013 (UTC)[reply]
Ok, thanks. I thought so, but I was not quite sure. Thank you. Joseph A. Spadaro (talk) 19:50, 2 June 2013 (UTC)[reply]

Link: Ibragim Todashev -- 189.40.64.239 (talk) 21:35, 5 June 2013 (UTC)[reply]