Wikipedia:Reference desk/Archives/Science/2014 December 7

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December 7

Concrete core in tall buildings

Do all tall buildings and skyscrapers have concrete cores which act as structural backbones? Is it not possible for these types of buildings to be supported only by a steel frame? — Preceding unsigned comment added by 82.132.216.222 (talk) 11:20, 7 December 2014 (UTC)

It certainly seems possible not to use a concrete core—see the third sentence of The Center, for instance. One of the main reasons for the use of the hull and core design seems to be that it reduces or eliminates the need for internal columns, permitting a greater amount of usable floor space. On skyscraper construction in general, see the article Skyscraper design and construction. Deor (talk) 11:39, 7 December 2014 (UTC)

IIRC the original World Trade Center buildings were of "steel frame" construction. See Construction of the World Trade Center#Structural design where it states:

“ The core of each tower was a rectangular area 87 by 135 feet (27 by 41 m), and contained 47 steel columns running from the bedrock to the top of the tower. The columns tapered after the 66th floor, and consisted of welded box-sections at lower floors and rolled wide-flange sections at upper floors."[1] ”

So it seem that the answer to your query is yes. Tube (structure) also discusses something similar, but the tube can be concrete as well as steel. --220 of ^Borg 15:21, 7 December 2014 (UTC)

It depends how you define "skyscraper". America's earliest skyscrapers didn't make significant use of concrete; that's why the Ingalls Building is so significant, as it was the first one to use a lot of structural concrete. However, the earliest skyscrapers were far shorter than today's tallest buildings (e.g. the first skyscraper, the Home Insurance Building, was ten stories), so I'm left wondering whether you're interested in them. Nyttend (talk) 05:33, 8 December 2014 (UTC)

Bamboo structural behaviour

What does the bending moment diagram on a bamboo cantilever with a point load on the end look like, given the fact that bamboo bends a lot? — Preceding unsigned comment added by 82.132.219.128 (talk) 12:22, 7 December 2014 (UTC)

I found Bamboo Bridge which may have some information. Alansplodge (talk) 22:21, 7 December 2014 (UTC)

Why don't people want to find out what kind of genetic disorders they have in their genes?

Why don't people want to find out what kind of genetic disorders they have in their genes, and what do health insurance companies have to do with it? I asked a librarian a related question, and I was given a response that health insurance companies somehow could increase the rates for some reason, as they would do to smokers. I am not an actuary, so I have no idea what's going on. However, I suspect that healthcare insurance companies want to minimize the risk of its consumers by not covering all kinds of expenses or decrease incentives for certain high-risk people. On the other hand, what happens if there is a major natural disaster and millions go broke and homeless and injured? Perhaps, there are different types of healthcare insurance companies suited for different purposes, and individuals and organizations have to choose whatever insurance or set of insurance that fits them best? Basically, what is the fear behind not wanting to know about genetic disorders embedded in the genes? I mean, even among people who have a particular gene, they may or may not express the phenotype. 71.79.234.132 (talk) 15:14, 7 December 2014 (UTC)

You can read many studies on this exact topic Here. Be aware, however, that immediately below my comment, many people will start to break the rules of the reference desk by telling you what they "think" about the question, and start giving you their own, unreferenced and unsupportable opinions. You can safely ignore them. --Jayron32 18:22, 7 December 2014 (UTC)

Genetic disorders differ in how they are expressed. Some like Huntington's disease and Gerstmann–Sträussler–Scheinker syndrome are both always expressed if present and always fatal, and yet they don't manifest symptoms until adulthood. Finding out that you carry the genes for a disease like that is guaranteeing an early, and often painful, death. That is understandably frightening to many people, especially since there is little or nothing that can be done to affect the outcome. Deciding how to deal with the fear of potentially receiving a severe genetic diagnosis is often a very personal and emotional thing. Some people would simply prefer not to know rather than learn that their life is going to be substantially shortened. Other genetic conditions, like the BRCA1 breast cancer mutation, only increase the risk of a disease without guaranteeing it will occur. In those circumstances, one can often take proactive steps to reduce the risk, so an early genetic diagnosis may be quite helpful. With regards to health insurance companies, in an unregulated world, the easiest way for them to reduce their expenses would be to ensure that the people that they cover are as healthy as possible and deny coverage to anyone that is likely to need many future medical treatments. If they know that a given person is likely to develop an expensive genetic disease requiring frequent treatments (e.g. repeated surgeries for polycystic kidney disease), then health insurance companies could save money by either not covering that person or by only offering them coverage with extremely high payments / deductibles. Of course, health insurance is regulated. In the US it is illegal for health insurance companies to use genetic information when setting rates or denying coverage. Even though it is illegal, some people still fear that health insurers will secretly use that information against them. Dragons flight (talk) 18:48, 7 December 2014 (UTC)

Thank you. That actually answered my question. 71.79.234.132 (talk) 20:09, 7 December 2014 (UTC)

Thank you as well, 71.79.234.132; you're that one IP in a hundred who actually bothers to offer thanks and provide feedback to us on the value of the response. It's quite important, and we appreciate it. Please come again. :) Snow talk 06:26, 9 December 2014 (UTC)

• This archived thread addressed the same topic from a different angle. μηδείς (talk) 06:35, 9 December 2014 (UTC)

Papain as male contraceptive

The male contraceptive article mentions papaya seeds as an effective and safe option, with references, but not being a subscriber to any medical journals, I can't see what the active ingredient was (if the scientists actually isolated it). The journal abstracts mention the "chloroform extract" and "methanol sub-fraction", but are those just ways of preparing the seeds for a test dose?

Would papain be the chemical in question? — Preceding unsigned comment added by 104.156.240.172 (talk) 16:55, 7 December 2014 (UTC)

I looked at the two references cited in male contraceptive. Neither indicates that the specific chemical is known. As you suggest, the chloroform and methanol are related to ways of preparing the seeds. Specifically, those chemicals appear to be used to dissolve and concentrate the active agent, whatever it is. One of the papers says that: "Initial attempts to identify the chemical composition of the [methanol sub-fraction] through IR, NMR−1 and MS revealed that the product is a homogeneous mixture of long chain fatty esters." That's about all that is indicated in those papers about the identity of the active agent. Neither paper mentions papain. As papain is available as a nutritional supplement, I would be surprised if it was known to have a contraceptive effect. Given the context, and the lack of mention in the papers, it would seem more likely that the active agent is something else that hasn't yet been fully characterized. Dragons flight (talk) 19:29, 7 December 2014 (UTC)

Okay, so I guess as Fgf10 says below, they didn't find out what it is. Thanks for looking 104.156.240.172 (talk) 00:59, 8 December 2014 (UTC)

As a point of clarification, our article says papaya seeds were effective in langur monkeys. It also says no apparent ill effects were found on the organs of albino rats with long term treatment. (The title of the article makes me think they could be effective in albino rats too.) It may be that that the are other RS which found papaya seeds effective in other organisms (such as humans), but this isn't known from our article. It may be papaya seeds are safe when used in langur monkeys, but we have very little evidence for this with a single study on another organism (which I have no idea if it's a good model for langur monkeys). We can't even be sure they're safe for us on rats. The fact that they were traditionally used for contraception doesn't necessarily mean they are safe or effective. Nil Einne (talk) 22:01, 7 December 2014 (UTC)

(OP) Point taken about effectiveness, although it's hard to see how a teaspoonful of something eaten by people for millennia could do any harm. One of the abstracts I looked at used a rabbit model btw, not that it changes your point. 104.156.240.172 (talk) 00:44, 8 December 2014 (UTC)

Safety is a relative thing though. There's a good chance eating no one would have noticed something gives you a 10% increase risk of testicular cancer. Perhaps not even 50%. Particularly since the quantities, frequency, and length of treatment may vary from historical consumption. It's also easy to overestimate how common something was. And since you mentioned millennia, while the preservation of Mesoamerica knowledge and cultural history is far better than for a number of other indigenous American peoples, I don't think it's generally as good as for a number of European & Asian ones. This isn't to suggest that papaya seeds are dangerous, more that we should be careful in applying GRAS too far, particularly for something which may have been used sparringly (I see mention of papaya seeds being used as a spice, is it known if this was a historic use?). This does apply to many things besides papaya seeds. Nil Einne (talk) 02:29, 8 December 2014 (UTC)

No it isn't. It is a very simple question, as the extracts in question were administered orally. (Virtually) no proteins survive the stomach environment. So there is no way orally administered papain will directly affect fertility in that way. Small molecules could very well do so, but would of course require further study. Also, as a side note, you said that you couldn't tell if there was an active ingredient isolated, as it wasn't mentioned in the abstract. I can assure you that if there was, it would have been mentioned very prominently. Suffice to say, they didn't. Fgf10 (talk) 22:30, 7 December 2014 (UTC)

Thanks. I was wondering if the exact chemical might have been kept secret for commercial reasons, if someone was working on a pill version, but with that only made clear in the full article. 104.156.240.172 (talk) 00:51, 8 December 2014 (UTC)

I would like to see more description of the precise method of traditional use of the papaya seeds. Just because traditional use is safe [assuming it is] doesn't mean that a hasty modern-day imitation will match. For example, kava-kava is relatively harmless as pounded out by natives and soaked into water, but when the root bark is simply spooned into capsules and swallowed as a supplement it can do liver damage. A variety of ayurvedic medicines are said to be detoxified by ritual preparation, and in some cases I recall it seemed plausible, at least, that this would help. And of course to take the cake there's tobacco, which the American Indians used to reinforce solemn ceremonies like peacekeeping but was soon beyond homicidal in the hands of Europeans. In the meanwhile, one small animal study for safety and one small animal study for effectiveness don't actually prove a medical claim, and certainly we are in no position to recommend it for medical use here.

Also, a chloroform extract would denature or remove many proteins to start (see phenol-chloroform extraction for related content); this is almost surely one or more small hydrophobic compounds. The compounds involved could be determined in a fairly straightforward but somewhat laborious manner of systematic identification and testing, either in vitro or in vivo; though it is possible multiple compounds contribute and/or that synthesizing the chemical turns out to be costly. Wnt (talk) 07:22, 8 December 2014 (UTC)

James Watson's remarks

What did James Watson really say recently? And why is it necessarily wrong to believe that intelligence can be genetic, and different group of people can different amounts of it (like different ethnical groups have a different average height). — Preceding unsigned comment added by Noopolo (talk • contribs) 20:01, 7 December 2014 (UTC) Noopolo (talk) 20:02, 7 December 2014 (UTC)

This is discussed in James Watson (sections labeled "Provocative comments" and "Avoid Boring People, UK book tour"). The issue really started from comments he gave in an interview in 2007. I'm not sure if the original interview piece is available online, but the meat of the matter has been discussed in many places, such as [2]. Dragons flight (talk) 20:12, 7 December 2014 (UTC)

PS. As regards the general topic, race and intelligence provides a detailed discussion of whether or not there are measurable differences in intelligence between the colloquially identified races, and if so, whether those differences are genetic or environmental. Dragons flight (talk) 21:12, 7 December 2014 (UTC)

Following on Dragons' comments and the article section he sites, it's worth noting this is not nearly the first time Watson has been known to make comments with a bit of a eugenics undertone to them. The man may have played a central role in understanding physical mechanics of DNA, the relevance of which to modern genetics cannot be understated, but when it comes to understanding contemporary genetic findings as they relate to human intellect and behaviour (and the cognitive and neurosciences broadly), his notions are antiquated and betray a profound lack of understanding of developments in these fields in recent decades. Now, you ask why it is wrong to believe that certain broad genetic groups may have divergent mental capabilities, and this asks for a value judgment and this seems to be asking for a bit of a value judgement of the type we should be avoiding here, but I'll say this much for my own perspective (which I think we can fairly well imagine will be shared by most of the other contributors here) -- it terms of the scientific process, it would not be wrong to aknowledge this reality, if the evidence were there. But that's the crucial point -- the evidence points very much in the opposite direction; that is to say, that on the scale of human genetic populations, people are largely very uniform as regards mental capacity in pretty much every type of cognitive task. Needless to say, consensus derived from the "scientific" investigation of divergence of intellect and other mental capabilities with regard to race did not always match with this modern understanding; previous to (and well into) the twentieth century, the belief in a highly stratified racial hierarchy in terms of human intellectual capacity was not uncommon and led to a proliferation of now discredited disciplines and techniques for supporting these notions (consider, for example, phrenology) -- notably championed almost exclusively by white Europeans and Americans, who, not altogether coincidentally, were members of the class of human put at the top of this intellectual hierarchy. As more modern and empirically rigorous methods for exploring the human mind, and the physical mechanisms from which it arises, these ideas died an extremely slow and protracted death, especially in the field of psychometrics, which some feel continues to exhibit empirical flaws owing in large part to its racialist heritage (pun most assuredly intended).

Regardless, today the scientific community for researchers who actually investigate cognitive phenomena in general (which it is worth noting James Watson is not a member of), and its relation to genetics in particular, is overwhelmingly united in its findings that race does not play a significant role in human intellectual capabilities -- or, if I'm to be a bit more accurate, serious science in the relevant fields tend to view both race and intelligence as a single quantifiable phenomena as vague and not terribly empirical concepts. It's not just that assertions to the contrary are not "politically correct" -- though certainly they are understandably offensive to many -- but rather that they are simply not factually supported by serious research in the modern cognitive sciences. I don't think Watson's comments were rejected so loudly by the scientific community out of overzealousness, but rather from a fair assessment that his role in the history of genetics could lead some to accept his assertions at face value as representative of actual research in fields in which he is not actually involved and that these claims might breath new life into notions or racial superiority. The truth is, there's probably no shortage of scientists from Watson's generation who believe these kinds of ideas, but most of them do not receive the level of attention that he does. Snow talk 21:56, 7 December 2014 (UTC)

http://www.atlassociety.org/tni/james-d-watson-another-gadfly-swatted for an interesting take on the matter. Greglocock (talk) 22:12, 7 December 2014 (UTC)

"Interesting" to say the least. I can't say as that article impressed me overmuch with either its journalistic or empirical rigor; the author admits (in the closing section) to having "no deep knowledge" of the relevant science, but still has no qualms about describing the response to Watson's comments as the result of sandbagging by an interviewer involved in one of the instances of his controversial statements (said interviewer being an admirer and former colleague of Watson's) and media hype, denigrating and calling into question the comments of just about everyone referenced but Watson himself. Watson's case is certainly not one of a few isolated comments taken out of context -- his opinions on these matters are well documented and have been made in highly public platforms over a significant number of years. When someone tries to recontextualize those comments with statements like "Anyone who has ever been involved in a news event knows that the media coverage of it is essentially false.", it's hard not to draw the conclusion that they are willing to make some fairly bizarre and clearly unrealistically broad claims to support a conclusion they're already set on. When someone says “all our social policies are based on the fact that their intelligence is the same as ours—whereas all the testing says not really,” that's really pretty unambiguous (and also not in any way reflective of actual research in the field). I appreciate that this article comes from the Atlas Society and I can see how an objectivist might feel inclined to perceive Watson's views as the type of thing that might be true and merely suppressed due to unpopularity -- historically objectivist ideology has been closely associated with the notion that some people are innately superior to others and that their right to pursue their gifts and destiny in that regard should not be shackled by those who are merely uncomfortable with that "reality" -- but this article goes through some rather substantial mental acrobatics in order to characterize this as a case of a scientist being censored merely because his findings happen to conflict with a "PC" view, when in reality they are very much in conflict with the consensus view of scientists who happen to work in the relevant fields. It's worth noting, though, that much of the article is concerned more with Watson's opinions on the gender divide for intelligence, which are rolled into one issue, but in fact are quite separate areas of inquiry. Snow talk 00:36, 8 December 2014 (UTC)

Having been on the receiving end of the journalistic method, on a technical article, I must admit that "Anyone who has ever been involved in a news event knows that the media coverage of it is essentially false." seems quite accurate to me. Greglocock (talk) 01:07, 8 December 2014 (UTC)

Well, I'm sorry to hear you had to go through a situation where you feel your stances were mis-characterized and maybe even maligned, but to me a statement like "The news is always false" is such a clumsy and imprecise exaggeration of the issues with media veracity in general (or representation of the sciences in particular) that it doesn't do much to impress me with an author's ability to parse the subtleties inherent in any scientific debate of this nature -- especially when I encounter it in a context where that author is framing the (overwhelming) majority view of scientists as mere politically-motivated noise. Snow talk 02:14, 8 December 2014 (UTC)

As someone else who has had their scientific research misrepresented in the media, I have to agree that the media coverage is always so 'simplified' that it becomes either unrecognisable as the original work or just plainly wrong. Fgf10 (talk) 13:38, 8 December 2014 (UTC)

Yes, but again, there's a vast gulf between saying "Research often gets distorted in popular media." and saying almost literally the phrase "Anytime the news reports on anything, it is a lie." I'm as critical of media distortion as the next person, particularly as regards coverage of the sciences, but I do feel language discussing these issues should be kept in the realm of the vaguely realistic. My intention was not to endorse the exact opposite extreme ("The media always tells the truth") or anything remotely like it. I'm only saying that, for me, claims of persecution do not gain much credibility when the person who makes them characterizes the source of criticism as a purely negative force which exists only to serve nefarious purposes. I certainly can support the notion that modern news media often operates under the influence of deep institutional flaws that can lead to all manner of misinformation in a variety of contexts. But to say that it only exists to lie and never accomplishes anything but? Come on. And honestly, the quote in question is even more hamfisted than that. I sympathize with both of you more than you know, but your situations are not analagous to the scenario that article treats. This isn't a case of Watson having his research misrepresented -- the field in question is not his area of expertise; rather he made some very dubious (and some people feel, deeply racist) claims -- repeatedly, over years, and in highly public contexts. Other scientists, including actual experts in the field he was pushing these claims on, understandably decided to decry his positions as unscientific and unsupported by actual findings. The Atlas Society article attempts to re-frame that fallout as the result of Watson being ambushed by a conniving former protege out to make her bones by throwing her former mentor under the bus and a complicit media that's out for his blood for....sensationalism, I guess? The author doesn't real explain their motivation, only implies the deep and abiding dishonesty in everything they do. The problem is, it doesn't fit, any of it. Watson made no secret that he held these views. He made them a feature of his memoirs. He made public statements in support of them in interviews, lectures and other public speaking engagements. He clearly does not view these notions as racist (or in the cases where he has been accused of misogyny, sexist), but that doesn't change the fact that he did support them, publicly and vocally. Saying that the media has hyped this case just seems to me to be asinine; even if a given news outlet would have been inclined to sensationalize his words, they never needed to -- what he said was about provocative as you'd ever get from such a figure. Snow talk 15:23, 8 December 2014 (UTC)

Oh, I wasn't trying to defend Watson at all, his statements were just plainly wrong at best, I entirely agree. Just making a more general statement about science and the media, I guess. Fgf10 (talk) 16:00, 8 December 2014 (UTC)

I hate to step into the middle of this; but I think the issue is not that Fgf10 is saying "The media reliably lies, and thus we can safely believe the opposite". It sounds more like he's saying "The popular media often oversimplifies scientific issues, to the point where the usefulness of their statements is marginal at best in understanding scientific principles". It isn't that the news is reliably false, it's that the news is reliable one way or the other. --Jayron32 17:30, 8 December 2014 (UTC)

Entirely correct. Just wanted to make clear that it was a general statement, which is most likely not true in the Watson case, where he does seem to have actually made those rather unwise statements. Fgf10 (talk) 21:13, 8 December 2014 (UTC)

Heh, ok, laughing out loud now guys (in a convivial way) at this game of recursive telephone I've somehow initiated. Yes, yes, and yes -- I know that's what Fgf10 was saying, I know that was what Greglocock was saying, and I see that you are saying now Jayron. It doesn't surprise me, because it was something I tried to concede from the outset. In each instance of my response in this chain I've been trying to make as expressly clear as possible that I see media distortion of these issues as a problematic, somewhat omnipresent issue -- while also underscoring that the invocation of that principle by this particular article's author seems to me to be absurdly boogeyman in nature, in that A) the wording was so absolute as to be awkward and silly B) it didn't fit the facts of this particular case in that the media -- including even those aspects of it that might have wanted a sensational story -- needed only faithfully report Watson's own public record to get it. We're all on the same page, I believe. Snow talk 21:58, 8 December 2014 (UTC)

Schröckingerite

What are the uses of Schröckingerite? --Allin Bagsnott (talk) 22:02, 7 December 2014 (UTC)

The OpticalMineralogy ref cited in that article identifies several uses. DMacks (talk) 22:09, 7 December 2014 (UTC)

Using fabric scissors to cut paper

People who are into sewing seem to have the consensus that using fabric scissors to cut paper will blunt the scissors quickly and harm their performance cutting fabric. Is there any scientific basis for this or is this baseless hearsay? I mean, obviously any time a blade is used it's going to be progressively dulled but is paper going to contribute disproportionally? --78.148.108.62 (talk) 23:31, 7 December 2014 (UTC)

We've seen this question before, let's see... here we are. Snow talk 00:05, 8 December 2014 (UTC)

I'll add to my comments in the previous thread that while this is clearly a highly contextual question, my overall gut impression is that this belief is probably more the product of folk science than any actual general trend. That is to say, I think if you took the varieties of scissors most commonly used for industrial/commercial purposes and tested the rate of dulling when applied to the fabrics most common in the relevant industries and then compared them against rates for using those same scissors on the most common varieties of commercially available paper products, the rate of dulling would be similar or greater for the fabrics, collectively, simply owing to the amount of resistance these typically thicker and more densely-knitted substances would present during cutting, which translates to more mechanical stress at the site of interaction between the blades of the scissors and the material itself. But that's really largely speculation, so do treat it as such. Snow talk 00:55, 8 December 2014 (UTC)

Paper may contain silica, calcium carbonate, kaolin clays, etc and I could believe these are hard enough to dull a sharp edge. But the other part of the story is that to cut cloth, you want scissors to be quite sharp. Using sharp scissors for other uses will just dull them faster. By contrast even kids scissors will cut paper--you don't need especially sharp scissors for this, so any dulling isn't noticed as much. Save the precision instruments for their intended uses. --Mark viking (talk) 00:16, 8 December 2014 (UTC)

Since the last time that question was asked, I'm even more convinced that this is an old-wives' tale. You definitely need sharper/tighter scissors for cutting cloth than you do for paper. So it really does make logical sense to keep one pair of scissors for cloth - which you use relatively rarely, so they stay sharp/tight - and another pair that you use for everything else that doesn't need a good pair to cut - and which can be allowed to wear out somewhat, and you don't care. It would make good logical sense to do that even if paper was LESS likely to wear scissors than cloth. So it doesn't surprise me that someone who does needlework would want to keep a separate pair for cloth...and tell everyone else not to use them for anything that doesn't require a really sharp pair. That's good logic - even if paper doesn't dull the scissors any more than cloth does. However, old wives being what they are...it would be no surprise if generations of needleworkers didn't pass on a really good, practical rule ("Keep cloth and paper scissors separately") for the wrong reason ("Paper dulls your scissors"). These very old, much-handed-down ideas very often have a grain of truth embedded in a matrix of bullshit!

However, there is no proof of this....I still can't find any experimental data. What I do know is that when I'm cutting cloth, I have to use a lot more force to do so - and I'd certainly expect that to result in more wear than when cutting paper. 22:03, 8 December 2014 (UTC)

More or less my thoughts exactly. But completely speculative. But then, so are old wives tales. It's hard to answer a question like this with any veracity when it's of such niche interest that it unlikely to be treated with actual research yielding definitive data. OP is advised to again treat our impressions in this case as a best guess. Snow talk 02:14, 9 December 2014 (UTC)