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May 22

Where does it go?

This may be a physical science matter or it may be about perception, i.e., psychology.

When planting a plant in the garden, the procedure is:

- dig a hole putting the soil to one side

- knock the plant with attached soil out of its pot

- place plant and attached soil in hole

- use the soil that was put aside to fill the rest of the hole.

(Putting some fertilizer in the hole is a better method but that not the issue here.)

My expectation when doing such planting is that there will be soil "left over" because a) the soil in the ground was more packed down initially than when it is replaced and b) the soil that came with the plant is put in the hole as well.

However my frequent experience is that there is no soil left over, that I have to borrow soil from elsewhere to end up with more or less level soil around the plant.

Physics or psychology? Thanks. Wanderer57 (talk) 01:44, 22 May 2011 (UTC)[reply]

Maybe when shoveling it out you spread it around a bit more than you thought, then only picked up the big chunks when putting it back. Also, did you remove any rocks or junk ? StuRat (talk) 04:29, 22 May 2011 (UTC)[reply]

(EC) If you are just putting the soil to one side (and probably not being extremely careful about it) it isn't surprising. You're not likely taking back all the soil when you refill the hole. If you do it in a grassy area this is usually obvious. If you very carefully put the soil in to a bucket or other container instead to the side you're more likely to get what you expect (depending on how loose the soil was before and whether you pack it down). Nil Einne (talk) 04:30, 22 May 2011 (UTC)[reply]

Also see soil compaction, soil structure - soil naturally has some empty space, in large part due to the workings of earthworms. Of course, you also add air when you put the soil back in loosely... still, it might be part of the explanation. Wnt (talk) 08:54, 22 May 2011 (UTC)[reply]

The 'soil' in the pot is likely to be compost, which compresses easily. Even if soil was used in the pot, it is likely to be far more fluffy and compressable than the other soli. 92.15.21.174 (talk) 11:56, 22 May 2011 (UTC)[reply]

Thank you all. I'll do some "controlled" planting and report later. Wanderer57 (talk) 15:44, 22 May 2011 (UTC)[reply]

I usually attribute this to two things. Firstly, as noted above, a lot of soil will get lost in transfer. Secondly, when you're refilling the hole where the plant now rests, you're packing the soil down (whether you mean to or not). There are probably a lot of other factors too. Juliancolton (talk) 19:46, 22 May 2011 (UTC)[reply]

Prandtl Number

Is it correct to say that the Prandtl number is a function of temperature and pressure only? Thanks --58.175.33.56 (talk) 05:56, 22 May 2011 (UTC)[reply]

A Prandtl number can be assigned to a fluid. First, the fluid must be identified (steam, oxygen, air, water etc.) Once the temperature and pressure have been identified the dynamic viscosity, specific heat and thermal conductivity of the fluid can be quantified unambiguously. So I think it is correct to say that for the nominated fluid it is a function only of temperature and pressure. Dolphin (t) 08:02, 22 May 2011 (UTC)[reply]

Nerve plexuses in G.I.T. (from mouth till anus)

Q. Name the nerve plexuses of gastrointestinal tract GIT from mouth till anus in a sequence. (as studied there i got two plexuses, submucosal plexus and myenteric plexus. But answer required must be with respect to each organ. like sublingual plexus, oesophageal plexus, pharangeal plexus, etc) please enlist the names of nerve plexuses present in git from mouth to anus.—Preceding unsigned comment added by MFSN (talk • contribs) 09:25, 22 May 2011

This looks like a homework question. We don't do people's homework for them. Tell us how far you have reached, or what part of the question is troubling you, and we will try to assist. Dolphin (t) 11:28, 22 May 2011 (UTC)[reply]

It sounds like the OP has explained his confusion, though not very well. To start with, let's see what we have: submucosal plexus, myenteric plexus, sublingual plexus, oesophageal plexus, pharyngeal plexus. I had to make a redirect for the "oesophageal"... In general, because of the rather loose definition of a plexus, this looks to be a rather confusing topic - consider the various little plexuses diagrammed in celiac plexus (File:Gray848.png) Nerve plexus has a lot of information, but coming up with a single canonical list? Not that simple. Wnt (talk) 12:40, 22 May 2011 (UTC)[reply]

Wnt please respect the no homework policy.—Preceding unsigned comment added by Dodger67 (talk • contribs) 16:06, 22 May 2011

Oh come on now. Wnt was doing an excellent job of supporting the no homework policy, and in a very positive manner. 190.56.108.15 (talk) 16:39, 22 May 2011 (UTC)[reply]

By giving a fairly obviously wrong answer (e.g. pharyngeal after oesophageal?), Wnt has illustrated the dangers of asking us homework questions. If the OP cares to spell out their current best answer and state their confusion, they may get a better response. -- Scray (talk) 11:01, 23 May 2011 (UTC)[reply]

THANK ..................................... K YOU

http://postimage.org/image/1gkn1hjqc/

Two days ago, I bought a bottle of Vitamin B&C from Costco. They taped the thermal paper receipt on the bottle. Today I noticed that the letters covered by the tape are simply ... GONE!

Why? -- Toytoy (talk) 13:42, 22 May 2011 (UTC)[reply]

That printing method is horrid, and the least stable of any printing method, so the worst possible choice for financial records. I noticed that highlighter also takes off the writing. StuRat (talk) 15:17, 22 May 2011 (UTC)[reply]

When a store offers some sort of a guarantee, the usual condition is that the receipt must be produced. If receipts are printed with "vanishing ink", the effective guarantee period is reduced.

Probably just a coincidence. Wanderer57 (talk) 20:58, 22 May 2011 (UTC)[reply]

Agreed. Some of the recipe even have warnings (pre-printed on the back side of the paper roll) that the receipt should be stored in some very restricted temperature and humidity range, which I think is impossible to do at home. If you actually want the receipt to last, your best bet is to photocopy it. – b_jonas 08:48, 23 May 2011 (UTC)[reply]

Sodastream fuel

If I were to carbonate some petrol would it still work in an engine? Rixxin (talk) 13:59, 22 May 2011 (UTC)[reply]

Hmm, possibly. However, putting petrol in a Sodastream will quickly dissolve the major working parts, and you'll end up with petrol all over your kitchen (if you discharge the CO2). Not the safest of situations to be in. This article might be of interest from a purely scientific point of view, although the pressures involved are much greater than anything you can reach with domestic apparatus. Why do you want to do it, as a matter of interest? Tevildo (talk) 21:35, 22 May 2011 (UTC)[reply]

I'm most certainly not going to do it! I wouldn't risk messing up my car! Besides all the warnings of mess, I don't even own a Sodastream. It was just an idle thought really, and I thought it might be an interesting question. I'm interested by your opinion that it would dissolve all the working parts of the Sodastream. My neighbour's Sodastream looks like this, the only contact between the petrol and the Sodastream would be the nozzle (and the plastic bottle, obviously). Assuming the petrol actually retains the fizz, I thought on balance that the presence of the CO2 would inhibit ignition in the engine, but was interested to find out.--Rixxin (talk) 08:30, 23 May 2011 (UTC)[reply]

Instead of carbonating, what if you fizzed it with a nitrous bulb! Maybe that's what the OP meant?? The responsible part of me wants to write a disclaimer that this is completely stupid and dangerous! But the juvenile pyromaniac in me wants to try it and post it on youtube! Lol… Vespine (talk) 06:15, 23 May 2011 (UTC)[reply]

I see, so that it would have it's own oxygen supply, instead of relying on air (in other words, we're making rocket fuel). But you'd still have the nitrogen in there slowing the reaction, just like with air. How about if you start with napalm, then whip it up with pure oxygen, or perhaps ozone ? Can we get a high explosive out of this ? StuRat (talk) 07:04, 23 May 2011 (UTC)[reply]

It was specifically carbonating I was considering, given the potential effects on the ignition of the fuel (as mentioned in my longer reply, above). --Rixxin (talk) 08:30, 23 May 2011 (UTC)[reply]

Australian wildlife

Why are practically all Australian animals deadly? Most have lethal venom, and almost all of the rest have razor-sharp claws/fangs. --75.40.204.106 (talk) 17:43, 22 May 2011 (UTC)[reply]

The creatures I think of in Aussie are marsupials, and a koala or wallaby just doesn't seem that deadly to me. StuRat (talk) 17:58, 22 May 2011 (UTC)[reply]

Your premise is incorrect -- very few Australian animals are deadly. DRosenbach ^{(Talk | Contribs)} 17:59, 22 May 2011 (UTC)[reply]

Kangaroos have claws that can disembowel a person, platypuses have poison spurs, just about every snake and spider is poisonous enough to kill a healthy adult, the rivers are full of alligators and crocodiles, the waters off the coast are full of sharks and poisonous fish/octopi, etc. --75.40.204.106 (talk) 18:08, 22 May 2011 (UTC)[reply]

Nope, No aligators. HiLo48 (talk) 20:38, 22 May 2011 (UTC)[reply]

That's quite ridiculous. Most any large dog can kill a person if given the opportunity and the means and the instictive desire -- does that mean, given let's say that 12% of Brooklynites have dogs and 35% of those dogs are big dogs that Brooklyn has so many deadly animals? Kangaroos will likely flee rather than fight and platypuses are hard to come by and only the males have spurs. There are four veneous snakes in the United States, yet that hardly correlates to a high attack rate. This is just such an amorphous question. African animals are very dangerous too...there are crocodiles and baboons and lions and cheetahs and hyeanas and elephants and hippopotamuses -- are they less dangerous, more dangerous or of equivalent danger? DRosenbach ^{(Talk | Contribs)} 18:49, 22 May 2011 (UTC)[reply]

... the rivers are full of alligators and crocodiles - let me address that. There are no alligators in Australia. The Freshwater Crocodile is endemic to Australia, but only in the very sparsely populated northern regions (see map). The Saltwater crocodile is also found in northern Australia (and some other places). Most Australians have never seen a crocodile and stand virtually no chance of being attacked by one. Even those who live in croc areas are warned about the dangers; the sensational stories we sometimes see are usually about people who ignored the warnings. -- Jack of Oz [your turn] 20:33, 22 May 2011 (UTC)[reply]

Then why is Australia often thought of as the land of Everything Trying To Kill You, to the point that that tvtropes article had to give Australia its own section? --75.40.204.106 (talk) 19:53, 22 May 2011 (UTC)[reply]

Journalistic sensationalism.190.56.108.15 (talk) 20:08, 22 May 2011 (UTC)[reply]

In addition I would point out as nasty as platypus venom is, as our own article says it doesn't kill you (presuming you is any resonably sized human) and there have been no recorded human fatalities. Perhaps 75 has different definitions of 'lethal' and 'deadly' then us. Nil Einne (talk) 20:18, 22 May 2011 (UTC)[reply]

Further to put things in to perspective, according to [1] 70 deaths have been attributed to box jellyfish in Australia since 1884. 63 according to [2]. Meanwhile the first ref earlier says there are 90 deaths per year from box jellyfish in the Philippines (which seems rather high) and the second ref says 20-40 per year is a resonable estimate. Even taking the lower figure this is still much higher then Australia even per capita, although the level of medical care is generally rather different. [3] claims "The box jellyfish is responsible for more deaths in Australia than snakes, sharks, and salt water crocodiles put together" which wouldn't surprise me. Meanwhile from [4] there were 11 deaths from dog bites in 1979-1996 in Australia. Nil Einne (talk) 20:29, 22 May 2011 (UTC)[reply]

A while later but looked for this because of something I came across while searching on a related topic. I see this has already been mentioned below although not in relation to my point. Anyway the claim box jellyfish kill more people then snakes, sharks and crocodiles put together seems dubious if snakes have really killed 41 people since 1980 whereas box jelly fish have killed 63 or 70 people since 1883. However it doesn't substanially change my point which is that none of the 'lethal' animals in Australia actually kill that many people and dogs should be up there as well if you are including things like snakes and box jellyfish in terms of number of people they kill. (Let's not worry about bees.) Nil Einne (talk) 15:05, 9 June 2011 (UTC)[reply]

I think the thing about Australian wildlife is that the big animals that you notice, the marsupials, are generally harmless, but the little guys will get you - the spiders, snakes, box jellyfish and marine stingers, etc. Oh, and have you heard about the mysterious mosquito borne diseases? Crocodiles, of course, are big. HiLo48 (talk) 20:38, 22 May 2011 (UTC)[reply]

I think it's also to do with Australia being so exotic and people being familiar with it mostly through National Geographic and The Discovery Channel-type outlets, and no one talks about Sydney as a city like any other -- they discuss the Outback and the bushlands, and when the tourists die it's big news. DRosenbach ^{(Talk | Contribs)} 20:56, 22 May 2011 (UTC)[reply]

The world is a dangerous place. what about all the millions of cows in Europe, England, U.S. Argentina etc. Have you seen the size of the horns on those things. They could spike you right through and disembowel you. No worries though 'caus as the human population of Australia increases, those incovenient species will be illiminated just as they have been around the world.190.56.108.15 (talk) 21:35, 22 May 2011 (UTC)[reply]

Yeah I think it's mostly media hype, I personally don't know of anyone who has died by "wild life", nor have I ever heard anyone else say they knew someone who died that way either. I recently moved out into a more rural suburb and we get loads of wild life, great birds like king parrots and kookaburras, loads of brushtail possums, various lizards, some amazing beetles and butterflies, frogs, we even saw an echidna, I don't feel threatened by any of those.. On the other hand I personally know of several people who have died from cars and drugs. Vespine (talk) 22:59, 22 May 2011 (UTC)[reply]

Crocs are not dangerous:

And sharks aren't that dangerous either:

Mike Rutzen is an expert on the great white shark and an outspoken champion of shark conservation. His fame spread due to the images of his free diving exploits swimming with the animals without a cage. Mike has spent more time swimming cage-less with great whites than anyone else. He has since travelled the world lecturing on sharks and filming documentaries on them.

Count Iblis (talk) 23:36, 22 May 2011 (UTC)[reply]

I challenge you to find four Australian species of spiders that will kill an average healthy adult human. I was under the impression that very few spiders around the world are capable of that. I have only found the funnel-back and a couple of species that have been recorded to cause a few fatalities. Also, I know that Australia has many very venomous snakes, but I was under the impression that these rarely attack people, and that antivenoms are available for most or all of them. I suspect that for every snake that poses a threat to human life in Australia, there are a bunch of them that don't. Having spent my time researching Australian spiders, I can't look into the snakes right now, but I don't think it's fair at all to say that in Australia "just about every snake and spider is poisonous enough to kill a healthy adult". I would suspect that you would find that just about every snake and spider is not a threat to a healthy adult, and the ones you hear about are the exceptions (also note that the news and documentaries seek out the exceptions. After all, what fun is it to provoke an Australian tree snake on camera, when it can't do anything to you? Falconus^{p t c} 04:41, 23 May 2011 (UTC)[reply]

Quite simply, none of Australia's 'deadly' animals (snakes, spiders, jelly-fish, sharks, sting rays, platypus, ants, crocodiles,Irukandji and a few fish) are likely to kill you, deaths from each range from 'no recorded deaths' to 2-3 a year, at most. Australian snakes and spiders are not particularly deadly, and very few cases require antivenom at all. Frankly, you are more likely to die from falling off a horse, or a bee sting in Australia. And all other native animals (kangaroos, emus, wombats and the like) will attack as a dog would, and there are far less cases than that. 1, all nicely summed up here 2, 3--JamesGrimshaw (talk) 06:01, 23 May 2011 (UTC)[reply]

Just watch out for the drop bears. Gandalf61 (talk) 13:08, 23 May 2011 (UTC)[reply]

And the bunyips.Vespine (talk) 22:52, 23 May 2011 (UTC)[reply]

See Category:Deaths due to animal attacks.—Wavelength (talk) 15:03, 23 May 2011 (UTC)[reply]

It's almost entirely because they have a fascinating untamed wilderness that that's fun to read and watch documentaries about. (And also it's a huge geographic region. So many animals are "in australia" even if you wouldn't find them within a week's walk of each other.)

For comparison here are some deadly animals from North America :

The following discussion has been closed. Please do not modify it.

Here in North America ...

---we've got a dozen varieties of snake that could theoretically kill you.

---We've got wolves.

---We've got Brown bears, Black Bears, and Polar Bears.

---We've got Alligators.

---We've got Cougars, Florida Panthers, and Jaguars

---We've got Foxes that have been known to eat human babies at least as often as dingos do.

---We've got Buffalo that could trample or gore you just as easily as a Kangaroo could eviscerate or kick you.

---We've got scorpions.

---We've got Black Widows and Brown Recluse.

And don't even think about swimming at our beaches. We've got several different kinds of sharks and jellyfish.

APL (talk) 22:43, 23 May 2011 (UTC)[reply]

And most of those listed do not really pose a threat to adults anyway. Bison, brown recluses, and a couple of the snakes certainly do, and some of the bears can get quite testy, but I never worry about any of the others listed when I am in a region where they are present. Of all of them listed, I am the most wary of the brown recluse where I live; it probably wouldn't kill me, but it would make my life miserable for a bit. Then the next two that I am most concerned about when I am in their territory would be the bison and to a much lesser extent, grizzly bears. I would add moose to that list, as they also can do some damage. Scorpions are somewhat overrated; most are no worse than a bee sting in the US (in fact, I think that the scorpion that got me was not as bad as that even). There are a few species that are "medically significant" but they are all in a very small area, I believe in Arizona. All in all, most of those animals are not likely to attack humans, and many of them will most likely run if you fight back (fox, cougars, black bears, etc), and one needs only a healthy respect for them to be safe around them. Falconus^{p t c} 03:25, 24 May 2011 (UTC)[reply]

You seem to have your fears backwards: black bears killed 16 in North America in the decade of the 2000s (while grizzly only killed 12 and the last polar bear fatality was 1999 (from List of fatal bear attacks in North America). And there have been zero confirmed brown recluse deaths ever.[5] But 11 fatal shark attacks and 13 fatal alligator attacks in the 2000s, at least 6 fatal snakebites. I see records for that time period of one fatality each for: mountain goat, bison, wolf, coyote (although only two fatal coyote attacks have ever been recorded) Rmhermen (talk) 04:19, 25 May 2011 (UTC)[reply]

Where did you get your information? That's interesting about the spiders, but I quote the article bison: "Bison are among the most dangerous animals encountered by visitors to the various U.S. and Canadian national parks, and will attack humans if provoked. They appear slow because of their lethargic movements but can easily outrun humans—they have been observed running as fast as 35 miles per hour (56 km/h)[citation needed]. Between 1978 and 1992, nearly five times as many people in Yellowstone National Park were killed or injured by bison as by bears (12 by bears, 56 by bison). Bison are also more agile than one might expect, given their size and body structure." Granted, that's not sourced either, but whenever I go to the national parks where both are present, it's my experience they tell you "don't feed the bears" and then say, with a lot of emphasis, "absolutely do not approach the bison, every year people are gored or killed by bison". Maybe bison stopped killing people (i.e. people stopped being stupid) after 2000, but I'm curious as to where you found that? Falconus^{p t c} 17:13, 25 May 2011 (UTC)[reply]

Possibly Rangers exaggerate the danger of bison because it's unintuitive? Most people don't need to be told to stay away from bears. (although some people certainly do.)

I'd also like to add to my list [[Killer Bees] Coyotes Bobcats and Canadian Lynx. I dunno if bobcats or lynx have ever killed anyone, but they can take down deer, so it doesn't seem out of the realm of possibility. If they lived in Australia you can bet that they'd wind up on a list of deadly animals. APL (talk) 19:12, 25 May 2011 (UTC)[reply]

A bit of OR here, but I reckon the tiger snake, founder in the wetter areas of SE Australia, is one of the meanest, crankiest creatures around. If there's a choice between fighting and fleeing, the tiger snake will fight every time. They will chase humans. And the bite CAN kill if not treated quickly. A colleague of mine tried to tough it out after being bitten, and paid the ultimate price. HiLo48 (talk) 22:44, 24 May 2011 (UTC)[reply]

Morse taper

Some dental implant companies fashion a restorative abutment (thing that exists above the gum line) that fits into the implant (screw that exists below the gum line) with what they call a Morse taper, and I've heard that Morse taper is really only until 8 degrees even though some companies call it a Morse taper even though their implants exhibit 11 degrees of taper. But when I checkout out the article, I found it to be thoroughly underexplained and, in fact, it speaks of the taper in terms of inches of expansion per inch of taper, rather than degrees of taper. Can anyone elaborate? DRosenbach ^{(Talk | Contribs)} 18:44, 22 May 2011 (UTC)[reply]

Well, the article does give the taper angle of the various Morse keys (Column K in the table), but they're all around 1° 30', nothing like 8°, let alone 11°. It's certainly not trivial distinguishing between Morse keys and straight cotter pins with the naked eye - anything that _looks_ tapered won't have a Morse taper. Or am I misunderstanding your question? Tevildo (talk) 21:00, 22 May 2011 (UTC)[reply]

Not so. having handled/used many of those tools, even though the taper is very slight it very obvious to the ordinary eye. The 8 deg. you mentioned is not the taper, It's a bevelled end of a tool type. I couldn't find details of the dental fixture, but if the intended function of it's taper is to provide sufficient surface friction to hold it in place then it cannot be 11 deg. It would not work unless glue or some other fixing medium was used.190.56.108.15 (talk) 22:05, 22 May 2011 (UTC)[reply]

Great Exhibition Mast

Some time ago I saw a photograph of a circular metal plate set in the ground and looking rather like a manhole cover. The caption to the picture said this was all that remained of what used to be a mast on that spot. I believe that the location was The Great Exhibition at The Crystal Palace but my memory may be playing tricks. The caption said that the mast was suspended in the air by its guys such that base did not touch the ground. The purpose of the metal plate was to mark the spot for visitors to stand on so that they would be directly underneath the levitated mast. I have my own ideas on how this trick might have been done, but does anybody actually know? Finding the photo again would be good too: I'm not sure the plate still exists, the picture looked old enough to predate the destruction of Crystal Palace. Spinning Spark 19:23, 22 May 2011 (UTC)[reply]

“such that base did not touch the ground” Yeah, real ale has that effect upon me too. Or are you talking about the Skylon (tower)? Suppose crystal palace is close enough on a really good pub crawl.--Aspro (talk) 19:41, 22 May 2011 (UTC)[reply]

Yeah, that's the thing, I just found it myself and was coming back here to say so. Ok, I got it wrong, but the Festival of Britain was for the 100th anniversary of the Great Exhibition so it did have something vaguely to do with Crystal Palace. How did you know I like real ale by the way? Now about that picture of the drain cover...Spinning Spark 19:54, 22 May 2011 (UTC)[reply]

Ah - Museum of London Spinning Spark 20:30, 22 May 2011 (UTC)[reply]

Titanium Dioxide in fat-free half & half?

I was looking through the fridge this afternoon, and an ingredients label for half and half caught my eye. Titanium dioxide is a white pigment. Why is it in a food that presumably should already be white? Thanks, illogical pie^{(eat me)} 23:40, 22 May 2011 (UTC)[reply]

The "fat-free" means that there is a fat substitute in there. It is probably not white. Adding white pigment to it makes the resulting product appear to be a milk product and not some substitute with a little milk floating around in it. -- kainaw ™ 01:59, 23 May 2011 (UTC)[reply]

(edit conflict)Fat-free half-and-half sounds impossible unless you violate the laws of the universe in some paradoxical way, but assuming it can exist and not cause a tear in space-time, it would essentially be skim milk. If you every compare skim milk to whole milk, skim milk is translucent and not an opaque white. The titanium dioxide would help give some opacity to the half-and-half-like-substance to make its appearence more like actual half-and-half. --Jayron32 02:02, 23 May 2011 (UTC)[reply]

The bottles of skimmed milk I have in my fridge, 0.1% fat, look just like ordinary milk to me. Perhaps it might be used where the manufacturer has diluted things with water. 92.29.113.29 (talk) 11:35, 23 May 2011 (UTC)[reply]

Pour a glass of skim milk, and sit it side-by-side with a glass of whole milk. You can see a distinction between the two. Sitting in a bottle (which is larger than a glass) and also without a direct comparison, it is harder to see. --Jayron32 13:03, 23 May 2011 (UTC)[reply]

The "half-and-half" here refers to how it exists half in our universe, and half in a parallel universe, where the laws of physics are slightly different and do allow such a contradiction. :-) StuRat (talk) 06:13, 23 May 2011 (UTC)[reply]

Cancer researchers have found that Titanium dioxide dust causes cancer in rats. This may not be worrying, unless you're a rat. Cuddlyable3 (talk) 08:35, 23 May 2011 (UTC)[reply]

A rat...who snorts his half&half. If there's enough coffee-lightener in the cafe that it's starting to fill my lungs, I think there's a more urgent problem though. DMacks (talk) 08:45, 23 May 2011 (UTC)[reply]

Our own article links to [6] which reports genetic damage found in mice from titanium dioxide nanoparticles consumed via water. However the key finding of this study appears to have been not so much of the possible risk of titanium dioxide nanoparticles but more that nanoparticles like of titanium dioxide may be of risk even if the substance itself is inert. Nil Einne (talk) 09:41, 23 May 2011 (UTC)[reply]

(Link for puzzled non-US readers: half and half.)--Shantavira|^{feed me} 13:53, 23 May 2011 (UTC)[reply]

Thank you, I was just about to ask. Wouldn't it be great if they spoke English in America? DuncanHill (talk) 13:57, 23 May 2011 (UTC)[reply]

Would be better if the English would take note of the fact that the English language is no longer their property. --Trovatore (talk) 22:49, 23 May 2011 (UTC) [reply]

But, the English language is a borrowed language. If anything, it is joint property of the French and Germans. -- kainaw ™ 12:32, 26 May 2011 (UTC)[reply]

Titanium is a bio-compatible metal and is used in many types of medical grade implants (hip, dental, etc.). When the surface is rough, it undergoes osseointegration and it is the titanium oxide layer that allows for fusion to the bone. DRosenbach ^{(Talk | Contribs)} 22:46, 23 May 2011 (UTC)[reply]

Thanks, illogical pie^{(eat me)} —Preceding undated comment added 22:10, 24 May 2011 (UTC).[reply]

Wikipedia:Reference desk/Archives/Science/2011 May 22

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