Wikipedia:Reference desk/Archives/Science/2011 May 2

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May 2

Visions of the technological future in 1999

I am trying to sort the list of "secret projects" in the 1999 Sid Meier's Alpha Centauri by how likely they could become real. So far I have: "the merchant exchange" (was true before publication), "the planetary transportation system" (was true before publication), "the planetary datalinks" (was true and keeps coming true in more geographies), "the network backbone" (was true -- is it still?), "the human genome project" (came true), "the supercollider" (came true, big deal), "the universal translator" (Google Translate on Android seems to qualify.)

These haven't come true yet as far as I know: "the longevity vaccine" (okay if seen as a stand in for general medical advances), "the cyborg factory" (if standing in for general user interface improvements), "clinical imortality" (not sure), "the self aware colony" (not sure), "the cloning vats" (maybe for organ replacement therapy?), "the living refinery" (can't that be done without microbes?), "the telepathic matrix" (only as a stand in for news corps improvements), "the weather paradigm" (I hope so!), "the theory of everything" (no idea; not sure I care), "the neural amplifier" (is this even a good idea? Can't we have non-invasive neural coupling instead?)

These I hope will not happen: "the pholus mutagen" (good heavens I hope not!), "the dream twister" (I sure hope not!), "the ascetic virtues" (individuals and ecology better than groups and ecologies.)

These I am sure won't happen: "the space elevator" (requires materials with tensile strength which are not likely without non-atomic states of solids), "the nano factory" (energy storage and heat dissipation limit the size of general purpose robots above the nanoscale), "the singularity inductor" (the singularity depends on nanobots), "the ascent to transcendence" (requires nanobots.)

Are there any reasons to believe otherwise? 173.8.151.126 (talk) 01:55, 2 May 2011 (UTC)

The space elevator isn't totally impossible. It'd be very hard to do on earth (impossible with today's technology), but it's technically feasible now on the moon or Mars, though of course not politically or economically feasible at the moment. It's the subject of lots of current research- see the "21st century" section in that article. Staecker (talk) 02:10, 2 May 2011 (UTC)

I concur that the space elevator might happen, though a rotating orbital tether to boost SpaceShipTwo-like vehicles might come first. Though I'm not sure what the nano factory does, I doubt that energy storage is a permanent limitation (see induced gamma emission - though I never did get an answer whether FRET would work on it, which would greatly reduce the lost heat). I also suspect that heat dissipation might be handled with advanced solid-state solutions, microfluidics, etc. Within the loose interpretation of a game, I see no reason to suppose that many societies are currently more ascetic than the U.S. - I'd count it as an accomplished project. As for pholus mutagen, I see no reason why Earth life couldn't be adapted to resist alien acids/thorns/whatever they have. Non-invasive neural coupling does seem conceivable, but not easy. Now for Dream Twister, you need to amplify "psi attack", but how is that defined? Methods of affecting the brain directly are conceivable but there's nothing that obviously possible. In the end... it is very, very hard to say that something is impossible. Wnt (talk) 04:13, 2 May 2011 (UTC)

The two that you classified as "came true" are "the human genome project" and "the supercollider", but I don't see why. The Human Genome Project started in 1989 and I think it was obvious by 1999 that its completion was just a matter of time. The only particle accelerator I know of with "supercollider" in its name was the Superconducting Super Collider, which was canceled in 1993. The supercollider page says that it's a generic term for high-energy particle accelerators, which is not my experience, but in any case, it also says that the Tevatron is a supercollider, and that has been operating since 1983. -- BenRG (talk) 05:56, 2 May 2011 (UTC)

I'm more confused about the A.I. parts and need to watch http://singularityu.org/videos/2010/02/neil-jacobstein-artificial-intelligence-what-how-and-when/ 173.8.151.126 (talk) 06:08, 2 May 2011 (UTC)

Civilization after peak oil

Assuming global oil peak will happen in 2030 approximately, one can assume global oil supply will be greatly diminished by 2100. Assuing alternative energy resources will not be developed as an exact alternative to petroleum, I want to know what will happen to industrial civilization after 2100? Will the airline industry survive? Will the entire petroleum-based transportation system (this include ocean liners, cargo ships, cargo planes, trucks) collapse? --DavidPeak (talk) 03:57, 2 May 2011 (UTC)

I think coal-to-liquids offers at least a short term solution; in the longer term we should use solar/geothermal/tide/wind/etc. to create fuels. But it's conceivable that battery storage will eventually outperform chemical fuels, with continued investment. Wnt (talk) 04:16, 2 May 2011 (UTC)

Assuming we don't reach peak coal first! DuncanHill (talk) 12:03, 2 May 2011 (UTC)

Agreed.[1][2][3] 173.8.151.126 (talk) 04:39, 2 May 2011 (UTC)

Batteries charged by whatever means we deem most sensible will make sense for land based vehicles and shipping. Air travel, where weight is more of an issue, will be more of a challenge. HiLo48 (talk) 05:18, 2 May 2011 (UTC)

It is possible to make methane via the Sabatier reaction (from hydrogen and carbon dioxide), or the Fischer–Tropsch process (from hydrogen and carbon monoxide). These processes essentially are unburning methane. From them more complex hydrocarbons can be created via fossil fuel reforming the Wurtz reaction. This may be needed for aircraft, where batteries might not have a high enough energy density. However, at present, hydrogen is normally produced from methane, so there is no point producing jet fuel this way. In the future, if nuclear power is the major energy source, then this may be needed (until we run out of uranium (or tritium). Or, biofuels may take off, including from algae. CS Miller (talk) 07:12, 2 May 2011 (UTC)

I am not asking about how alternative fuel technology will develop in future, my question is will industrial civilization as we know it today survive in 2100 after peak oil? Please shed some light. Thank you. --DavidPeak (talk) 11:51, 2 May 2011 (UTC)

Shed some light? This is all speculation. Nobody can possibly know. Look how well the global financial crisis was(n't) forecast. It's obvious that many efforts will be made to find alternatives to oil, the results of which are likely to lead to a future civilisation with some similarities to ours, but all the differences one might expect over 90 years. Anyone remember 1920? HiLo48 (talk) 12:00, 2 May 2011 (UTC)

I don't think we will have to wait 90 years to see the effects of peak oil which is likely to happen in the next ten years. Dauto (talk) 13:57, 2 May 2011 (UTC)

Perhaps some insight to the shape of the future after peak oil can be gained by looking back at history. Whenever major civilizations have collapsed, there have always been a group of powerful individuals that have managed to retain control over sufficient resources and sufficient labour to carry on living in the style to which they have become accustomed. After peak oil passes, one can expect that a skilled workforce will be retained as a core group to ensure that an industrial base and infrastructure of sufficient critical size will be maintained which will ensure international trade and travel much like today. However, its main purpose and priority will be to serve the privileged few. Signs of this can already be seen today in some heavily industrialized countries. They keep a large proportion of their population made surplus by mechanisation, in a permanent state of unemployment and/or imprisonment. This enables the more powerful sections of society a greater share of their countries GDP whilst at the same time having a pool from which armies can be conscripted at very sort notice in times of national emergency. So, industries built on current technology will likely survive in a form that remains recognisable but the numbers of people that share direct benefit of these industries will diminish at the rate needed to maintain balance with any shrinkage in suitable energy resources. --Aspro (talk) 14:23, 2 May 2011 (UTC)

Civilization will survive, because in a few decades we'll have far more advanced robot technology and in about a century we'll have intelligent machines that will replace humans. Industrial civilization in the 2100 century will involve the colonization of the Moon, Mars and some other planets using self-replicating machines and factories. Whether this involves nano-technology or more crude technologies remains to be seen. But the basic point is the following.

If our economy grows, then we get more factories, that goods at a higher rate. But because humans are involved in almost all parts of the production process, this contrains the rate at which you can increase production. If, in contrast, everything is produced from raw ,material, including the machines to build the factories, the machines to get the raw materials out of the ground etc. etc., then the whole system can grow exponentially until the access to the raw materials gets compromized (e.g. because the whole planet as been covered by machines).

You can e.g. imagine that on the Moon one puts a machine that produces solar panels from the materials that can be found on the Moon and which makes a copy of itself. The machine is powered by solar energy. Suppose that this machine produces a solar panel of 1 square centimeter per month and makes a copy of itself in that time. Then, in just 4 years and 10 months, almost the entire surface of the Moon would be covered by solar panels. This example clearly illustrates that the bottleneck limiting growth is not oil, rather it is humans. Count Iblis (talk) 14:36, 2 May 2011 (UTC)

That makes no sense. Human beings are also self replicating machines. As you said, access to resources (including energy) is the limiting factor. Dauto (talk) 15:03, 2 May 2011 (UTC)

"Industrial civilization in the 2100 century will involve the colonization of the Moon, Mars and some other planets using self-replicating machines and factories." I don't believe so. --DavidPeak (talk) 15:12, 2 May 2011 (UTC)

Dauto, we don't use humans as self replicating machines in the production process. And, obviously, access to energy is also determined by the constraints imposed by the fact that humans are involved in the production process. With machines only, much more raw materials can be mined.

DavidPeak, see here. Count Iblis (talk) 15:46, 2 May 2011 (UTC)

Yes, we do use humans in the production process, and yes humans are self replicating, which leaves me wondering what point are you trying to make. Dauto (talk) 16:26, 2 May 2011 (UTC)

If you look the economy as one big system, then yes. But obviously you can't split off a small section of it (a few factories) and let that grow exponentially, because the workers in that factory won't make copies of themselves considered as factory workers, so you can't scale up everything.

Simple analogy: Our economy = Primordial soup of organic molecules that could grow as a whole, but single celled organisms had yet to arrive. And then after humans are automized away, we'll have the analogons of what we would call life: Self replicating entities that are relatively independent of the soup. Count Iblis (talk) 16:35, 2 May 2011 (UTC)

In the world where I live factory workers do make copies of themselves. Yes indeed. Dauto (talk) 17:02, 2 May 2011 (UTC)

There is a persistent myth that self-replicating fabbers will automatically lead to amazing near-free wealth, but it just doesn't hold up to close investigation. Many other, more difficult, technologies would need to be developed to turn self-replicating fabbers into free-wealth machines.'

(This is related to the myth that "free energy" could easily be converted into "unlimited space travel" without any other intervening technological breakthroughs.) APL (talk) 21:42, 2 May 2011 (UTC)

gravity field of crab nebula

it is mystery for me the properties of gravity field of crab nebula ,can I ask any one to explain it for me (about the total escaping mass and common center and the effect of gravity field on cloud )it is for the reason of what any where we don’t see characteristics of such field in scientific references akbarmohammadzade--78.38.28.3 (talk) 04:26, 2 May 2011 (UTC)

It would be good for you to be more specific about what you're interested in. From the article the Crab Nebula formed from a star 11 times the mass of the Sun, which shed a cloud 4.6 times the mass of the Sun, which now has a radius of 5.5 light years. The effect of a star's gravity overall is quite weak at such a distance, and the cloud is still expanding - fueled by the original collapse of the other 7 solar masses into a tiny neutron star, which emitted a lot of energy (the SN 1054 supernova). The Crab Nebula is of interest to researchers for gravity waves from the pulsar,^[4] or birefringence in transmission of quantum gravity.^[5] The gravitational potential energy shed by matter falling to the central neutron star actually limits how much material can fall back onto it, because it is emitted as electromagnetic radiation that emits radiation pressure.^[6] Wnt (talk) 05:23, 2 May 2011 (UTC)

High acidic nature of Pepsi and Coca-Cola

Respected Sir,I have learnt through one of my doctor friends tha Pepsi and Coca cola contain high acidity ( their pH value is even less than 3 ) , which means that they are very harmful for human consumption. I want to ask whether there is ban on use of Pepsi and Coca cola in the colleges,schools and Universities of US ? —Preceding unsigned comment added by 115.240.163.243 (talk) 05:18, 2 May 2011 (UTC)

Certainly not in general - the soft drinks are regarded as safe by the government, after all. The acidity is somewhat hazardous to teeth when they are sipped frequently. Some nutritionists place greater emphasis on the overall acid-base balance of the human body and of the urine.^[7] - for example it can affect formation of uric acid kidney stones. But this is seen more as usual wear and tear of a possibly unhealthy lifestyle than as a true poison.

That said, it is unfortunately not uncommon to find effective bans on Coca-cola as campuses sign exclusivity agreements with Pepsi, or vice versa.^[8] These agreements may also affect sales of healthier alternatives to either. Wnt (talk) 05:29, 2 May 2011 (UTC)

The pH of Coke and Pepsi is low, but its not lower than many foods which you may eat on a regular basis. Orange juice is more acidic, and depending on how strong you like it, coffee and tea may be as well. The pH of many salad dressings is lower than Coke or Pepsi. The contents of your stomach right now is FAR more acidic than Coke or Pepsi, indeed drinking Coca Cola will make your stomach considerably less acidic. No, the health problems associated with Cocal Cola and Pepsi have nothing to do with being acidic (excepting, the problems in general with eating too much acidic foods, guzzling too much Orange Juice will have the same effect), and everything to do with Coke and Pepsi are empty calories and have a low glycemic index. Basically, that means they provide energy, with no additional nutritive value (no proteins, no essential fatty acids, no vitamins or minerals, etc., just pure energy). Also, since the little bit of nutrients you get consists almost purely of simple sugars, it causes a rapid rise, and quick crash, of blood sugar levels, which has all sorts of implications for your health. There's LOTS of reasons why drinking too much soda is bad for you. The pH isn't really one of them. --Jayron32 05:51, 2 May 2011 (UTC)

Such items are banned from schools (but not colleges or universities) in England. Bazza (talk) 13:50, 3 May 2011 (UTC)

Software for arranging scientific diagrams?

What software do scientists use to ensure that published images of micrographs, charts and gels etc are all the same size and appropriately and consistently aligned with each other and with their labels? I've seen research papers where diagrams were blatantly arranged by eye in PowerPoint, but what software is used to achieve a professional appearance with a minimum of hair-loss? --129.215.47.59 (talk) 18:40, 2 May 2011 (UTC)

I produce professional papers in LaTeX format, which can be produced from many different programs - I personally use Kile. For posters, I create them as .svg files in Inkscape. -- kainaw™ 18:45, 2 May 2011 (UTC)

Latex is definitely the way to go within physical sciences and math. Often times the publisher will require the authors to follow templates provided by them in order to create some level of uniformity to the look and feel of their publications. The number and variety of softwares used to create the pictures and charts to begin with is too large for me to even attempt to make any sort of list. Inkscape mentioned above is one I also use, among many others. 24.73.119.146 (talk) 19:03, 2 May 2011 (UTC)

Personally, Adobe Illustrator, Matlab, and Microsoft Word are my predominant tools. Regarding the mentions of LaTeX above, it is going to depend a lot on the field. In climate science, for example, many journals prefer Microsoft Word over LaTeX, and a few journals will flat out refuse to take materials formatted for LaTeX. Rather than getting non-specific advice from the internet horde, you might have better luck talking to people who you think write good papers in your field and asking them what tools they are using. In some fields certain niche tools are well-established for the kind of work that needs to be done. Dragons flight (talk) 19:49, 2 May 2011 (UTC)

Agree on all sentiments. I'd also point out that how you format your images has nothing to do with how you format your paper as a whole. --Mr.98 (talk) 20:46, 2 May 2011 (UTC)

Wikipedia has an article about Management of baldness that may be helpful concerning hair loss. We cannot give personal advice for which consult a qualified trichologist. Cuddlyable3 (talk) 08:14, 4 May 2011 (UTC)

genetic engineering question

Do we (humanity) currently have the technology to genetically engineer a unicorn? That is create a horse which will grow a single stright horn out of the top of its head? Googlemeister (talk) 19:55, 2 May 2011 (UTC)

Doubtful Nil Einne (talk) 20:16, 2 May 2011 (UTC)

I agree, it's doubtful. The way to do it would be to take the genes for a horn from a horned animal and splice them into a horse's DNA. That kind of gene splicing can be done, the problem is that I think you would need more than just a few isolated genes. The genes that go towards a horn in a horned animal are probably also involved in other things, so it would be difficult to transfer them to a horse without affecting those other things. --Tango (talk) 20:22, 2 May 2011 (UTC)

So then how did they have that mouse grow a human ear on its back? Was that a hoax or some kind of skin-graft? Googlemeister (talk) 20:37, 2 May 2011 (UTC)

That wasn't genetic engineering. It had more in common with cosmetic surgery. See Vacanti mouse. --Tango (talk) 20:44, 2 May 2011 (UTC)

Notably, the mouse was intentionally immuno-compromised, so that it would not reject the implant. Immunocompromised mice are common in biology labs; they are usually created via selective breeding, which is arguably a form of genetic engineering. Nimur (talk) 20:49, 2 May 2011 (UTC)

If we could, then all the girls who now want a pony would want a mutant unicorn pony instead. Also, all the boys who want the moon will ask for moon rocks. – b_jonas 08:41, 3 May 2011 (UTC)

Not "currently" but if someone had maybe $300 million to throw at it, isolating the expression of horns in similar mammals and splicing that into a horse is probably a 5-10 year task at this point. The horn wouldn't look very good and the horse wouldn't have any instincts about it, so it might interfere with their diet and/or cause injury. 99.39.5.103 (talk) 16:54, 3 May 2011 (UTC)

... are there any animals that have genes for a single genuine horn? Dbfirs 19:01, 3 May 2011 (UTC)

A rhinoceros looks much like a unicorn, especially when you can't take a good look because it's after you and you are heading away full speed. 77.3.163.234 (talk) 20:34, 3 May 2011 (UTC)

A Narwhale would be the most obvious choice for the horn. Both mammals. A think maybe grafting would be the way to go. Quinn ^{✩ STARRY NIGHT} 20:38, 3 May 2011 (UTC)

... but neither a tusk nor a pure keratin growth is what I meant by a genuine horn, so I assume that there are no mammals from which to obtain the genetic code for a normal mammalian single horn, as suggested above. Dbfirs 08:24, 6 May 2011 (UTC)

Rhinos are also mammals... they are also fairly closely related to the horse compared to other mammals. They are both odd-toed ungulates. Whales are closely related to even-toed ungulates, though, so aren't that distantly related. The OP specifically asked about genetically engineering a unicorn. Getting a horse and sticking a horn on its head would be easy. --Tango (talk) 23:51, 3 May 2011 (UTC)

Even forgetting the horn, the concept of what a unicorn would look like is not precisely a horse. It's kind of like part small horse, part goat. In fact, I recall some years back someone tried to create an "articifial" unicorn from a goat, by somehow binding and twisting its two horn "buds" together. Not genetic engineering, obviously. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:19, 5 May 2011 (UTC)

Imersion in hot water

Two things. Firstly, I understand that putting something cold into something hot results in a pain relative to the temperature difference (something to do with the way the receptors work, I think). Question is: is it right to hurt more? Is it the temperature difference or absolute temperature that's more likely to cause damage? Secondly, it seems to me that areas on the water's surface hurt the most of all; why is this? 92.8.168.51 (talk) 20:21, 2 May 2011 (UTC)

I would say that the absolute temperature would cause damage. Thermal convection could be responsible for higher surface temperatures. Plasmic Physics (talk) 23:31, 2 May 2011 (UTC)

Also possibly, purely from experience of dipping into a hot bath, the part of your body closest to the surface is the part you've submerged most recently, even if it is only by fractions of a second, you will still most strongly perceive the heat on the most recently submerged part, maybe that adds to the perception that the surface is the hottest. For example if you dip your arm in and leave it for a minute and then pull your arm partly out, I reckon it will no longer feel any hotter at the surface since the temperature on that part of your arm will be relatively equaled out. Vespine (talk) 00:02, 3 May 2011 (UTC)

Smells of chemical weapons

A link on the front page led me to Private Snafu, and a very entertaining and instructive series of films they are. They've thrown up a question, though. In the "Gas" episode, when the enemy uses chemical weapons against him, Pte Snafu smells new-mown hay (Phosgene), apple blossom (?1) and flypaper (?2). What are ?1 and ?2? Tevildo (talk) 22:00, 2 May 2011 (UTC)

Tabun (nerve agent)? -- Finlay McWalter ☻ Talk 22:12, 2 May 2011 (UTC)

Or Soman. I'm not sure what WWII fly paper smells like, but probably organophosphates generally? Many chemical gases are not dissimilar from insecticides. --Mr.98 (talk) 02:10, 3 May 2011 (UTC)

When someone has checked this, the WP articles could do with having the smells added. Apple blossom is reminiscent of Phenacyl chloride. The fly-paper is a reference to a mixture of chloroacetophenone (Phenacyl chloride), chloropicrin and chloroform. http://articles.janes.com/articles/Janes-Explosive-Ordnance-Disposal/CNS.html

This is possible reminiscent to somepeople of fly-paper because it was coated in sweet smelling Venice turpentine which is not a liquid (nor a true turpentine) but a thick sticky very slow-drying resin from the Western Larch and insects stick to it, just as seen in amber. Also, fly-paper has deathly connotations to it, where as to reference the chemical weapon to similar resinous smells would not. --Aspro (talk) 09:20, 3 May 2011 (UTC)

Thanks very much! It looks as though we could do with an article on CNS gas, if that's it's common name. Tevildo (talk) 18:04, 4 May 2011 (UTC)

Foreign Health Patients In America

I often hear from opponents of public health that the European counties systems are so bad they have to send they patients to American hospitals for anything serious. How much truth is there to this? What are they statistics? --184.17.65.90 (talk) 22:49, 2 May 2011 (UTC)

I don't believe I've ever heard of the UK's NHS sending anyone to the US for treatment (it's very difficult to find statistics for something that appears to essentially never happen; the onus of proof should be on those who're telling you these things). You very occasionally hear of someone who has some obscure ailment for which only a "revolutionary experimental cure" can treat, and the newspapers run a fundraiser to send them to the US (although it's not at all clear that these cures are at all worth the bother). While there are many factors influencing average longevity, these opponents with whom you speak may be chastened by the US' rather poor position on list of countries by life expectancy. -- Finlay McWalter ☻ Talk 23:10, 2 May 2011 (UTC)

As Finlay says, in a vanishingly small number of cases European patients may travel to the United States to receive experimental therapies or participate in clinical trials for particularly rare conditions (for example, when U.S. centers are unable to recruit enough patients in their own country). A similarly minuscule number of patients will travel from the United States to Europe to receive experimental or unproven therapies. A small number of patients will also travel to the United States to avoid queues in their home countries (generally for elective procedures), for certain cosmetic procedures, or for 'luxury' hospital services (extra-large private rooms, premium meals, bigger televisions, etc. at a very substantial markup) provided by for-profit U.S. hospitals. Our article on medical tourism touches on some of these issues and links to a lot of sources for more information. In recent years, absolutely enormous numbers of Americans travelled overseas to receive less expensive medical care in locations from Mexico to Thailand. The number of patients leaving the U.S. (more than half to three-quarters of a million) far exceeded the number coming in (fifty to seventy-five thousand) each year; it will be interesting to see how health care reform in the United States affects these numbers. TenOfAllTrades(talk) 23:57, 2 May 2011 (UTC)

(ec) Even if they are this bad, do you think they would admit it by sending patients to other countries when they have no disadvantage when they try an unsuccessful cure? Doctor: this is the thousandth time I do this operation. Patient: this is good to heare. Doctor: I know it is bound to be successful some day. 77.3.163.234 (talk) 23:59, 2 May 2011 (UTC)

This is OR I'm afraid, as I've recently been asked to take part in fundraising for this purpose. There are treatments which are carried out in the US which are not carried out in the UK, either because they're too experimental or have no proven cost benefit, but which some patients may benefit from. Far from the NHS sending people to the US for this, people who wish to go to the US have to raise the money for such treatments and go privately. There is provision for people to go to other EU countries for treatment and the money will get reimbursed from the NHS. This was introduced to bring waiting list times down a few years ago, but I'm not sure it was ever pursued in great numbers (I only remember hearing of one case). --TammyMoet (talk) 09:16, 3 May 2011 (UTC)

Swimming with dolphins is the kind of thing I have heard the NHS declines to fund. 92.15.10.74 (talk) 11:41, 3 May 2011 (UTC)

...or sometimes because the treatment is illegal in the UK. For example, patients travelling to Switzerland to find medical staff who will kill them, or travelling to the US so they can select an embryo with or without a Y chromosome. 86.164.70.27 (talk) 13:05, 3 May 2011 (UTC)

The story I first thought of was this one. Not from England or even Europe, but they are from outside of the United States, and were trying to get in.... Kingsfold (Quack quack!) 17:58, 4 May 2011 (UTC)

The foreigners that come to the U.S. hospital that I work at are not sent here by their government. They come here by choice. I do not know of any list of reasons why they choose to come to the U.S. for care instead of remaining in their home country. It could be because the treatment isn't offered. It could be because they perceive the U.S. care to be better. It could be because they have to wait for treatment at home. It could be because they were on vacation in the U.S. and suddenly needed healthcare. There are foreigners receiving U.S. healthcare, so it is incorrect to claim it never happens. But, I don't see any reason to claim that foreign health programs specifically send foreigners to the U.S. for healthcare. Though - I just remembered reading an article a long time ago about a procedure that the Canadian system had a long waiting list for, so they paid to send a few people near the border to U.S. clinics. I'll see if I can find that article. -- kainaw™ 18:07, 4 May 2011 (UTC)

Found it, but it is in print-only in our library. The abstract states that was Vancouver paying a Seattle clinic for heart surgery due to long heart surgery waiting list. The article is from 1992 and refers to this as "last year", so I assume this took place in 1991. -- kainaw™ 18:12, 4 May 2011 (UTC)