Wikipedia:Reference desk/Archives/Science/2013 September 24

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September 24

Could polar bears move to mainland Norway and survive there?

From Bear Island it's only 400 km to the Norwegian mainland, polar bears are able to swim that distance. So, occasionaly polar bears could arrive in mainland Norway. But could polar bears survive on the mainland? Once on the mainland, the bears may not not need to hybernate, so they wouldn't need to find large amounts of food to build up enough fat reserves for that. They could perhaps supplement their diet with edible thrash they can find at landfills. Count Iblis (talk) 01:22, 24 September 2013 (UTC)

Is your question whether bears eat trash? μηδείς (talk) 02:21, 24 September 2013 (UTC)

This is speculation on my part, but brown bears and polar bears can interbreed. If just one or a few polar bears arrive at Norway, I assume that if they survive and breed, they will be introgressed into the population. Wnt (talk) 04:12, 24 September 2013 (UTC)

My New-Word-of-the-Day: Introgression, --220 of ^Borg 06:22, 24 September 2013 (UTC)

Sure they could. See Churchill, Manitoba where the bears survive uite well. They may eat the garbage but it's not their preferred food. CambridgeBayWeather (talk) 12:21, 24 September 2013 (UTC)

400 km is a huge distance to swim, even for a polar bear. Why would they choose to swim 400 km south when their immediate problem is the lack of sea ice on which to hunt? After all, they don't know that Norway is there, let alone that it might possibly have some tasty rubbish to eat. SpinningSpark 12:46, 24 September 2013 (UTC)

Some [polar bears (GPS tracked) indeed manage to swim those distance], although it's rare. I know that some polar bears reached Island, but above an iceberg. 15:26, 24 September 2013 (UTC)

But if they made it to the equator, would that turn them into cartesian bears? - ¡Ouch! (^{hurt me} / _{more pain}) 09:06, 25 September 2013 (UTC)

Spherical bears, more likely. ;-) 24.23.196.85 (talk) 22:11, 26 September 2013 (UTC)

Like these? - ¡Ouch! (^{hurt me} / _{more pain}) 12:28, 27 September 2013 (UTC)

Psychotherapy - Control Freak

What is the cure for a control freak? — Preceding unsigned comment added by 31.25.4.14 (talk) 09:03, 24 September 2013 (UTC)

There are a number of things wrong with this question. First, we don't provide medical advice, so can't "cure" anything. Second, there is no clinical definition of "Control Freak". Third, perhaps most importantly, there are, in general, no "cures" for mental issues in the same way that there are cures for the flu, and, really, only a trained psychologist/psychiatrist (like the one diagnosing) should provide anything related to alleviating the issue (as far as possible).Phoenixia1177 (talk) 10:13, 24 September 2013 (UTC)

Most "cures for the flu" don't do that either. It's a virus. Your body's own abilities and time are the main factors in getting rid of it.HiLo48 (talk) 10:22, 24 September 2013 (UTC)

I'm aware of that, but I think it works as an analogy; the point being that the concepts of what "cure" means in the context of the flu compared to ptsd are very different things.Phoenixia1177 (talk) 10:59, 24 September 2013 (UTC)

We have an article on Control freak but I don't think it will help you chill out and stop worrying :) Dmcq (talk) 10:17, 24 September 2013 (UTC)

OP thank you. Perhaps you are being a bit over-literal. I will rephrase. Control freak behaviour, perhaps as a result of psychological/environmental damage, or innate personality, perhaps a personality disorder (not something I suffer from, except in being on the receiving end) are destructive behaviours, to self or others - I wished to know in the context of psychiatry if there is a known method of correcting the personality/behaviour to "normal" (a bit like removing a phobia as one example). So that at the end of treatment, the person is a happy, cheerful, relaxed, fun to be with person instead of control obsessed. — Preceding unsigned comment added by 31.25.4.14 (talk) 11:41, 24 September 2013 (UTC)

Wanting to "fix" someone else's supposed problems in order to benefit yourself, sounds like its own version of "control freak". ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:50, 24 September 2013 (UTC)

WP:AGF BBB. SteveBaker (talk) 13:24, 24 September 2013 (UTC)

I don't assume any bad faith. I merely point out that the OP should consider who he's really trying to benefit. I'd have thought that was an obvious issue: "I don't like the way you behave, and I don't feel like changing in order to accommodate you, so you need to change instead, to accommodate me." ←Baseball Bugs ^{What's up, Doc?} carrots→ 15:15, 24 September 2013 (UTC)

Being a control freak is a personality trait - and unlike "fixing" a phobia, you have a hard time changing someone's core personality - and you might not like what they turn into when you do! If what you're asking is how to manage a control freak at work or at some social grouping, the usual trick is to swamp them with a mindless number of small details to micro-manage. They generally end up either learning to delegate or being so busy that they don't have time to bother you anymore. If the control freak is a spouse - then marriage counciling can do wonders. SteveBaker (talk) 13:24, 24 September 2013 (UTC)

My inner control freak obliges me to point out that you mean "counselling" (with one L, if you insist)AndrewWTaylor (talk) 13:28, 24 September 2013 (UTC)

Cognitive behavioural therapy has had some success with OCD, which is a form of control freakery. --TammyMoet (talk) 20:20, 24 September 2013 (UTC)

Interesting replies. Thankyou. Actually I was thinking of the problem in general. In UK at the moment we are inundated with a plethora of fiddling rules, which I suppose originate in some control freaks mind in a position of power. The end results are people being forced to follow rules, even when the result is disastrous, for one example a child died in a pond three foot deep because the community cops were told not to enter the water as they weren't trained in the procedure. And there have been other deaths in similar circumstances. Like psychopaths, the control freak is rarely inconvenienced by their characteristic but it can damage others. So I wasn't thinking of a particular person. But Steve Bakers reply made me think of one. I knew a perfectionist who appears to have been subjected to severe trauma, and now she is a control freak. That is she no longer observes normal social boundaries, but just dives in everywhere she wants with her meddling. As you suggest, although perhaps I have noticed the method by which a control freak is made, the process of undoing the damage is likely to be enormously difficult.31.25.4.14 (talk) 09:39, 27 September 2013 (UTC)

My food gives me a warm, glowing feeling...

...but perhaps that's because it's radioactive, containing isotopes like K⁴⁰ and C¹⁴.

So, my questions:

1) Does consuming these radioactive isotopes contribute to aging ?

2) Are they significant mutagens and carcinogens ?

3) Has anyone tried to remove the radioactive isotopes ? For example, if you could remove the radioactive potassium from fertilizers we use to produce food, that should significantly reduce the radioactivity of that food. I'm guessing that this can't be done in a cost effective manner, but just how costly would it be ? (I'm thinking of another aisle in the grocery store next to organic foods, with "low radiation foods", which would sell at a premium price.) StuRat (talk) 12:59, 24 September 2013 (UTC)

They are not significant mutagens, or carcinogens. They are not just in the fertilisers, they are in the very air we breathe, and in the ground, naturally occurring. Removing them would require isotope enrichment which should increase the price of products by several thousand percent. Plasmic Physics (talk) 13:07, 24 September 2013 (UTC)

According to Isotope_separation#Commercial_materials, only three elements have been isotopically separated for commercial materials, and K is not one of them. K^40 is sometimes separated to use as a radioactive tracer to study nutrient cycling, so you could probably look up prices from a scientific supply company. Short answer: I agree with Plasmic: fertilizing with depleted K would be insanely expensive, and have dubious benefit. SemanticMantis (talk) 13:12, 24 September 2013 (UTC)

Yes, but there might be a market for it nonetheless, as there is for organic foods. A "several thousand percent" increase in price might be acceptable to some well-to-do customers. StuRat (talk) 13:18, 24 September 2013 (UTC)

⁴⁰K and ¹⁴C are long-lived with low enough decay energies that they don't really do any significant harm to you. Given that you probably already have the average equilibrium amount of these isotopes in your body (K through homeostasis, C because it's a very common element and you'll be hard-pressed to find anything without it), abruptly stopping your intake isn't really going to do any non-negligible change to your daily radiation dose.

Particularly radiophobic well-to-do customers might be worried enough to consider foods supposedly with limited amounts of them; but if so, I would advise they reevalute their radiation priorities, since your average exposure from the air (mostly Rn) is on average four times as large as your average exposure from food! Double sharp (talk) 14:13, 24 September 2013 (UTC)

One very important unresolved issue is whether or not small radiation doses are bad for you. It might actually be good. The answer is not known for sure. read Radiation hormesis.Dauto (talk) 14:26, 24 September 2013 (UTC)

Or simply it's something we can deal with. Since we are constantly exposed to it, otherwise we would all be dead. OsmanRF34 (talk) 15:29, 24 September 2013 (UTC)

Just a ball-park analysis of price: Regular Glucose-D is available as a food additive and priced at $500/metric ton. Glucose-D labelled with C¹³ is manufacture and sold for medical applications (Carbon MRI specifically), and is priced in the range of $175-1700/gram (guessing that the 6 varieties offered are for how many C atoms in the Glucose molecule are substituted with C¹³). That is a price ratio of ~1,000,000.

Of course, there are several obvious caveats to this analysis (relative abundance of isotopes; refining for C¹³ vs removing C¹⁴; different processes for separation; meeting the medical vs food industry standards; economy of scale etc) but all in all I think the "several thousand percent" estimate would be unduly optimistic. Abecedare (talk) 15:21, 24 September 2013 (UTC)

That million-to-one price estimate is probably about right for something as simple as glucose - but making a carrot with no C¹⁴ in it would likely be a few orders of magnitude harder - and making a steak without C¹⁴ in it would probably cost more than putting a man on the moon. SteveBaker (talk) 15:37, 24 September 2013 (UTC)

I didn't say the food would have to be completely free of radioactive isotopes, but just at a measurably reduced level, which should be far cheaper. StuRat (talk) 11:18, 27 September 2013 (UTC)

Far in the future, someone will dig up the remains of the eccentric billionaire on a C¹⁴-free diet and get very misleading results from the carbon dating. Katie R (talk) 15:55, 24 September 2013 (UTC)

Actually, I don't think the precise quantity of C¹⁴ matters, as long as there is a sufficient amount. That's because the absolute amount of C¹⁴ isn't how age is determined, but rather the ratio of C¹⁴ to it's decay products. StuRat (talk) 11:20, 27 September 2013 (UTC)

• To address the first two questions: It's unclear whether low-level environmental radioactivity contributes to cancer, because (a) that radioactivity is present everywhere and impossible to get rid of, and (b) many cancers have unknown causes. On the other hand, it's very unlikely that it contributes to aging. Aging seems to be mainly a combination of genetically programmed changes over time, accumulation of protein byproducts in tissue, and gradual shortening of telomeres in the DNA. None of those would be affected by very-low-level radiation. Looie496 (talk) 17:49, 24 September 2013 (UTC)

• I thought an accumulation of genetic damage also causes aging. StuRat (talk) 11:18, 27 September 2013 (UTC)

Why produce metallic technetium?

Does anyone have an idea how and why the Tc shown in the picture in the article might have been produced? (Especially why, since the applications section of the Tc article doesn't mention any use of metallic Tc.) Double sharp (talk) 14:23, 24 September 2013 (UTC)

The obvious explanation is because non-metallic Technetium doesn't exist. When it comes to elements in the vast majority of cases "take it or leave it" is the only choice you have about the form it takes - metals are metalic, non-metals are non-metallic and so on. Some elements have a few different crystal structures e.g. carbon where you do have a choice, but they are the exceptions to the rule. Roger (Dodger67) (talk) 14:50, 24 September 2013 (UTC)

I meant why make Tc the element, not Tc compounds. Double sharp (talk) 14:55, 24 September 2013 (UTC)

The answer, of course, is the same as the answer George Mallory gave when asked why he wanted to climb Everest, at least in spirit. The answer Mallory gave, famously, was "Because it's there". The reason to create metallic technetium is because one CAN create it, and people who don't understand the fundemental human need to do things just to prove one can do them would never understand such reasoning anyways, but acceptable or not, that is the most likely reason why: it serves no greater purpose or reason than that it was possible to do so and someone wanted to do it. --Jayron32 16:56, 24 September 2013 (UTC)

Apparently one reason for producing metallic technetium in bulk is because in that form waste technetium can be processed in a nuclear reactor by neutron capture into stable ruthenium.[1] Presumably such processing of a compound or mixture would produce other undesirable isotopes as well. SpinningSpark 17:05, 24 September 2013 (UTC)

Thanks. Double sharp (talk) 09:58, 25 September 2013 (UTC)

Besides, the hard part is the creation of the elemement, not the chemical processing of the element into a metallic form which can be easily done by standard chemical procedures. So... Why not? Dauto (talk) 17:58, 24 September 2013 (UTC)

It's not that hard to create it, according to the paper I linked U235 yields 6% Tc99 in fission products. Sellafield, according to our technetium article, managed to dump 900 kg of Technetium into the Irish Sea between 1995 and 1999. Producing a couple of small pills of metal out of all that waste does not seem to be such a big deal. SpinningSpark 18:33, 24 September 2013 (UTC)

Is there a mechanism to 'turn off' feelings?

For example, if you are hungry and are confronted by a dangerous situation, would you brain 'turn off' the hunger and activate the being afraid, or at least cautious, feeling? OsmanRF34 (talk) 15:12, 24 September 2013 (UTC)

See Fight-or-flight response, which notes the suppression of various body functions during high stress situations, such as digestion and sexual response. --Jayron32 16:52, 24 September 2013 (UTC)

(EC) Jayron beat me to the link. You also might be interested in the differences between feeling and sensation and emotion and perception. SemanticMantis (talk) 16:57, 24 September 2013 (UTC)

Depression and various psychiatric conditions can supress many urges and "feelings" and various drugs also have such effects. Roger (Dodger67) (talk) 06:59, 25 September 2013 (UTC)

Need some help here!

Last night I left an answer here to the smart insects question and index a photo, but apparently did something wrong in lightroom because the exif info have my real email… can somebody more advance than me fix that? I have read some articles showing how to change all kind of stuff but now I don’t remember and don’t have time so I’ll appreciate that very much… Thanks

https://en.wiki.x.io/wiki/File:Avipa-asesina-LR-.jpg

Iskánder Vigoa Pérez (talk) 15:16, 24 September 2013 (UTC)

I can't see how to edit that page at all. Odd! Suggest you contact a Commons Administrator to delete the page, then re-load it without your e-mail. It appears that that info is added in the camera? You may have to change a setting there too so it isn't added. ExifTool may be applicable here. -©-220 of ^Borg 16:22, 24 September 2013 (UTC)

I can't help here, but thanks for that cool photo! SemanticMantis (talk) 16:22, 24 September 2013 (UTC)

The metadata is embedded in the file so it cannot be removed by editing the page. You need to upload a new version of the file with the metadata removed (or with only the metadata you want to be seen). You can then ask for an administrator on Commons to revdelete the old versions so it can't be seen in the history. Administrators on Wikipedia cannot do this as Commons is a separate project and you have uploaded to Commons, not to Wikipedia. SpinningSpark 16:43, 24 September 2013 (UTC)

I will assist Iskánder and upload a corrected version in case nobody gets to this in the next hour or so. Nimur (talk) 16:53, 24 September 2013 (UTC)

Oh man… I thought it would be easier… that’s very odd, I don’t remember have input my mail in the d90, I don’t even know how to do it — Preceding unsigned comment added by Iskander HFC (talk • contribs) 16:59, 24 September 2013 (UTC)

It's a great photo! Can I ask where geographically was this photo taken? I'd like to try to identify the tarantula hawk species in the image, but I need to know the location for that. Thanks in advance! --Dr Dima (talk) 17:05, 24 September 2013 (UTC)

Above at the insect question [2], Iskander says he's in Cuba. That should be enough of alocation to help ID, unless there are tarantula hawks endemic to different specific valleys or something. SemanticMantis (talk) 18:09, 24 September 2013 (UTC)

Your email was added by PhotoShop when you used it to edit the image -- at some point you set up PhotoShop to use a generic copyright statement that includes your email address. You should be able to remove it by editing the image again with PhotoShop and changing the copyright metadata -- however the version with the email address would still remain in the file history until a Commons admin deletes it. Looie496 (talk) 18:12, 24 September 2013 (UTC)

You can remove the metadata without any application, at least you can in Windows 7. Right click on the file icon on your computer, click on properties, click the details tab, click "Remove Properties and Personal Information". SpinningSpark 18:27, 24 September 2013 (UTC)

Nimur, I watched your notifications, thank you very much, but I’m very short in time, I do renders and only come here to refresh in the inter-times… here you can learn some very interesting things

Thanks all for the answers… the personal data like name and location really doesn’t bother m e, it’s just the email, but if it means too much trouble to cut it out, I’ll be fine, and will take more care next time

Iskánder Vigoa Pérez (talk) 01:03, 25 September 2013 (UTC)

Feminism and Science

Okay, so I'm supposed to be writing a paper on feminism and science, and have to read up as many articles on the topic as I possibly can. What I need is pointers. Can someone recommend good articles written on the topic? (Articles are preferred since going through an entire book is harder with a month's deadline.) I've already collected some essays that anyone can find after googling things like "feminism and science" or "feminism versus science". The reason for posting this here is that some of you might know relatively unknown (or not so obvious) titles or authors. Bonus points if they're pro-science (I'm taking a pro-science stance), and also if they write intelligible English and not the jargon-filled garbage that humanities students are prone to using. 202.153.41.162 (talk) 18:06, 24 September 2013 (UTC)

I'm a bit confused - "feminism versus science" and "pro-science stance" makes it sound like you're framing feminism and science as opposite each other. There are certainly a lot of feminist scientists and pushes to get more women into STEM fields. Parts of the skeptic community heavily push feminist ideals and a pro-science viewpoint. Katie R (talk) 18:36, 24 September 2013 (UTC)

@Katie: I am framing them opposite each other. I don't see where your confusion lies. 202.153.41.162 (talk) 18:53, 24 September 2013 (UTC)

What does "feminism vs. science" mean? That's like saying "abolition vs. mathematics". ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:14, 24 September 2013 (UTC)

[ec]I don't have anything to contribute, but I am curious about how this turns out because it seems like you are comparing apples to pencils here. If we had a better idea of what you were looking for, perhaps we could help a little better. Feminism isn't the opposite of science; it's the opposite of not-feminism. Science is the opposite of unsubstantiated guessing. Mingmingla (talk) 19:15, 24 September 2013 (UTC)

To be more specific, my paper talks about feminists' accusations of how science is a male dominated field, and scientific reasoning is a masculine "tool of oppression" as opposed to feminine intuition. I want articles that talk about how a feminist approach to science might look like, whether it's a reasonable enterprise, or, if not, why. Also whether it's the fault of science in particular that we have more male scientists, or the fault of the society and its constructs. 202.153.41.162 (talk) 19:19, 24 September 2013 (UTC)

Blaming science for how some male scientists might treat female scientists is like blaming the game of baseball when a pitcher throws a spitball. The "fault" is not in science, it's cultural - as in upbringing and old established societal norms, as indicated in the last part of your statement. That's your proper focus for this subject. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:27, 24 September 2013 (UTC)

• (ec) Obvious intersections are sociobiology and evolutionary psychology. Feminists who are of a want to deny innate differences between the sexes are going to challenge claims that women are designed as nurturers by biology. μηδείς (talk) 19:21, 24 September 2013 (UTC)

Women_in_Science,_Technology,_Engineering,_and_Mathematics_(United_States) would be a good starting point. Skimming it, it seems to cover a lot of the arguments about why women are underrepresented in the fields and approaches for addressing the imbalance. It looks well-referenced, so it should provide quite a few sources for you. Katie R (talk) 19:25, 24 September 2013 (UTC)

Women in computing is one area that interests me. My feeling is that having some women around improves the social aspect and makes teams work better. However even though, umm don't hit me for being non pc here, even though women practically got an automatic pass through in our job screening if they were anyway good enough (we didn't say that!) we still couldn't find the number we wanted because so few go in for computing. The situation used to be much better in the past. Dmcq (talk) 21:02, 24 September 2013 (UTC)

• The "masculine tool of oppression" notion isn't a criticism of a certain type of science, it is an attack on the notion of any objective science--objectivity being one of those masculinist ideas. You might profit from a look at Stephen Hicks' Explaining Postmodernism (just found the book is available for free as a pdf from the author) which is one of the standard college texts on the subject. It gives you a wider context in which to look at such "feminist" attacks. (I'd prefer to call them post-modern feminist, since they have little to do with Friedan or de Beauvoir. μηδείς (talk) 21:27, 24 September 2013 (UTC)

Are you talking about postmodernism-vs-science with a focus on feminism? If so, are you looking for books, internet, or journal resources? It's a topic I used to have an interest in (the broader one), I know I have some material still around at home, if this fits the bill, I can dig some up.Phoenixia1177 (talk) 03:41, 25 September 2013 (UTC)

@Phoenix: That would be much appreciated, thanks! Yes, something along those lines surely. I'm very to new the arts (I've recently shifted from a science background) , so my ideas are still very half-baked. I need to do a lot of reading! (= 202.153.41.162 (talk) 06:08, 25 September 2013 (UTC

• Go to newscientist.com and input your search terms there, "Women in science" and "science and feminism" come up with plenty of hits but you will need to find someone with a subscription to access some of the full articles. Richerman (talk) 22:02, 25 September 2013 (UTC)

There is no such thing as a feminist opinion of science, or a scientific opinion of feminism. Among feminists, you'll find every imaginable opinion about science. Plenty of people think science is fascinating, awe-inspiring, and gives humanity unlimited potential to make the world a better place. I'm one of those people, and though I'm not a feminist activist, most people would consider me a feminist sympathizer. On the other hand, you have radical feminists like Sandra Harding who called Newton's Principia a rape manual and thought E=mc^2 was a sexed equation. For more information, see Science Wars. I also highly recommend Higher Superstition: The Academic Left and Its Quarrels with Science by Gross & Levitt, which has been recommended before on these reference desks. It's a condemnation of postmodernism and its willingness to play fast and loose with the facts. It also has a section dedicated to feminism. Keep in mind, however, that this book was written 20 years ago. Since then, the humanities have become much more epistemologically conservative, and consequently more sane. --Bowlhover (talk) 05:45, 26 September 2013 (UTC)

Since most feminist critiques of science are based on postmodern thought, you might find Sokal_affair a useful link. OldTimeNESter (talk) 14:58, 26 September 2013 (UTC)

I should think that actual science (versus a random bunch of misogynostic scientists) would rather support feminism, in that it has no use for social conventions, tradition, etc., which are all forces that oppose feminism. For example, if we include economics under science, having a larger pool of skilled workers, by training and then employing women, clearly has the potential to help the economy. And the scientific method would have us test out new things, like career women who never marry, to determine if this is a workable model, rather than just judging them as being bad. StuRat (talk) 11:13, 27 September 2013 (UTC)

See also Lawrence Summers#Differences between the sexes. Duoduoduo (talk) 13:28, 27 September 2013 (UTC)

You may be interested in ecofeminism, where I see the same shift that Bowlhover has described. Recent ecofeminist theory tends to critical realism rather than social constructionism. Like social ecology generally it has no quarrel with science as a method of enquiry but is critical of the way that science is mobilised for military purposes, agribusiness and other questionable pursuits. Itsmejudith (talk) 07:38, 28 September 2013 (UTC)

Shear force

In the following example, why is the parallel axis theorem used to calculate the second moments of area of the 4 parts of the beam sticking out? Clover345 (talk) 19:29, 24 September 2013 (UTC) http://academic.cuesta.edu/jjones/Engr52/homework/6-29.pdf

Because you need I of the whole beam. Incidentally that answer is a fail, even by my scrappy standards. Random equations that come up with the right answer is not acceptable.Greglocock (talk) 01:10, 25 September 2013 (UTC)