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February 6

is couscous a liquid?

I was looking at liquid and wondered if couscous counts as a liquid. My gut says no but the definition says yes. 0¹⁸ (talk) 04:17, 6 February 2017 (UTC)[reply]

The definition: "A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure." OK, looks good for couscous, except what is a fluid? Well, that is, "a substance that continually deforms (flows) under an applied shear stress." Uh, check. That's basically restating the container requirement. 0¹⁸ (talk) 04:42, 6 February 2017 (UTC)[reply]

I can make couscous into a cone shape that will just stand there in the center of a container. It won't necessarily change shape to conform to the container. A liquid generally would, and I can't shape it into something else the way I can couscous. --OuroborosCobra (talk) 04:53, 6 February 2017 (UTC)[reply]

Couscous is probably best described as granular matter. There is no sharp boundary between liquids and amorphous solids with respect to how fast or how easily they need to deform under shear stress (see for example asphalt and pitch drop experiment). In non-Newtonian liquids (see oobleck for example) the situation is even more complicated. Does this help? Dr Dima (talk) 05:22, 6 February 2017 (UTC)[reply]

Couscous will jam if you try to press it too hard or pour it from too fine a pipe, which a conventional liquid won't. Smurrayinchester 08:49, 6 February 2017 (UTC)[reply]

Pour water through a hypodermic needle. No cheating. Sagittarian Milky Way (talk) 09:19, 6 February 2017 (UTC)[reply]

You need to increase pressure to jam particulate matter, whereas capillary effects (the cause in your example) occur regardless of pressure. Tigraan^{Click here to contact me} 16:25, 6 February 2017 (UTC)[reply]

No, definitely not. You might make a case for it being a fluid though. Most solid powders can be fluidised, if lubricated or agitated appropriately. Andy Dingley (talk) 09:24, 6 February 2017 (UTC)[reply]

The confusion here seems to be caused by the failure to recognise that (in scientific use) all liquids are fluids, but not all fluids are liquids. Wymspen (talk) 10:17, 6 February 2017 (UTC)[reply]

A better definition of a liquid would be based on the behavior of the constituent particles (atoms, molecules, and/or ions) that make up the substance, specifically the manner in which the molecules move and are bonded to one another. Couscous is clearly a solid by that definition. That the individual pieces of couscous "flow" of a sort is really not relevant. Functionally, couscous is semolina, and as such, is nearly identical for chemical purposes, to lasagna noodles. No one would describe lasagna noodles as a liquid. When you have chunks of matter, it "flows" of a sort in the sense that the individual pieces will respond individually and will slide and slop past one another. But that is not what a liquid is. I mean, functionally, pouring couscous out of a box isn't any different than the movement of boulders in an avalanche, and those boulders aren't liquid. --Jayron 32 15:20, 6 February 2017 (UTC)[reply]

Looks like we lack a link to couscous. StuRat (talk) 01:14, 7 February 2017 (UTC)[reply]

Units of Mass

It's easy to say that the units of mass are a kilogram, slug and pound but how did physicists determine/calculate the mass of an object first independently (without force and acceleration) in such units or while formulating F = ma = mg. Are force and acceleration necessary for the measurement/calculation of mass in aforementioned units? 2001:56A:7399:1200:F41F:EAAF:2DAB:EA49 (talk) 05:55, 6 February 2017 (UTC)EEK[reply]

The pound is weight, not mass as such, although we have Pound (mass) which gives some history. A balance scale won't work in a weightless environment. The force involved is gravity. The metric system is easier to understand, because everything in it is derived from the meter. ←Baseball Bugs ^{What's up, Doc?} carrots→ 06:33, 6 February 2017 (UTC)[reply]

No; some of us were taught in school that that basic "pound" is a weight unit and not a mass unit, but that's wrong. All countries where people still use pounds have agreed to define the pound as 0.45359237 kilogram. For example, here's the relevant bit of the Weights and Measures Act in Canada. Anyway, for purposes of the question it suffices to focus on kilograms. --76.71.6.254 (talk) 11:53, 6 February 2017 (UTC)[reply]

Trovatore posted a really interesting comment when the mass-vs-weight thing came up on the science desk a few months ago: There was a guy on alt.usage.english, I think his name was Gene Nygaard or something similar, who looked into the history of the linguistic issue. If I recall correctly, he came to the conclusion that this insistence on "weight" as force as opposed to mass does not come from the physics community at all, but from the physics education community. I have not examined his evidence in detail, but this seems plausible to me. Weight-as-force is not a very fundamental quantity for physics; it's relative to the local gravitational field rather than being a property of the object. It's fundamental for certain branches of engineering, but engineers are not so picky about this sort of thing. But for physics teachers, it's very convenient to have a separate word, even somewhat arbitrarily chosen, because getting students to understand that two concepts are different is already challenging without having to use the same word for them. -165.234.252.11 (talk) 16:39, 7 February 2017 (UTC)[reply]

[ec]They didn't -- they simply defined mass so that the force an object exerts on the ground due to Earth's gravity would equal mg. 2601:646:8E01:7E0B:49DC:6C5:C30C:C726 (talk) 06:35, 6 February 2017 (UTC)[reply]

You can measure weight without knowing anything about force or acceleration, as with a balance. It just has to be relative to something else. Indeed, the entire purpose of defining units of weight was not to make measurements possible, but to make sure that they meant the same thing wherever you went. Someguy1221 (talk) 06:34, 6 February 2017 (UTC)[reply]

This method (w=mg) is only applied if the center of both the relative mass and the object whose mass is to be determined are at equal distance from center of the earth. Theoretically, precision deviates when there is difference in center-to-center distance (due to shapes) b/w masses and earth

Addendum

we know that w = mg

Left Hand Pan = Right Hand Pan

m1 g = m2 g where

g = GM/d^2 where d is the o/c distance between earth and mass m or from the center of an earth to the center of mass m

G = Gravitational constant

M = mass of gravitating object say earth

So m 1 (GM) / d1 ^2 = m 2 (GM) / d2 ^2

We get; m 1 / d1^2 = m 2 / d2^2

Although for simplicity we use d1 = d2 while in reality, it's hard to bring them equal. Lets measure the mass of earth on a very mammoth pan balance relative to platinum alloy on an imaginary celestial body. Assume the shape of mass of celestial body, an earth, and platinum alloy are spherical. Earth is on Left-Hand pan while the Mass of 5.97219e24 kilograms of platinum alloy is on the Right-Hand pan

So RH pan = LH pan therefore m1GM/ d1^2 = m2GM/d2^2

Where m1 = mass of earth, m2 = mass of platinum alloy, M = Mass of celestial body, d1 = the distance b/t the centers of earth and celestial body, d2 = the distance b/t the centers of mass of platinum alloy and celestial body

So m1/d1^2 = m2/d2^2; m1=m2 if d1=d2 but they are not because of difference in densities of earth and platinum alloy 2001:56A:7399:1200:61FD:4D40:C201:2A8F (talk) 08:11, 6 February 2017 (UTC)EEK[reply]

It seems to me that the original question could apply to length, time etc. as well. The answer is that the original unit was defined so that such-or-such thing had a given measurement. In the (original) metric units length was measured as a multiple of the length of a meridian, in others systems it is described as a multiple of an average foot, but the conceptual idea is the same.

If we are talking specifically about mass, there is an additional trick: in theory, two concepts of "mass" overlap. Inertial mass is the constant used in Newton's second law F=ma, gravitational mass is the property used in the gravitational law F=G m_1 m_2 / d^2, and there is no reason a priori that the two should be equal. Empirically they are observed to coincide exactly (or at least within a precision that we cannot measure); see equivalence principle. Tigraan^{Click here to contact me} 10:45, 6 February 2017 (UTC)[reply]

Weighing equipment ID

Hi

The equipment in the attached photo was in a small wooden case and has been left on my desk by my boss to identify.

Does anyone have any idea what this equipment is/was used for?photo of equipment

thanks Gareth — Preceding unsigned comment added by Gpashley (talk • contribs) 12:08, 6 February 2017 (UTC)[reply]

It's a Westphal balance, see the German article de:Mohr-Westphalsche Waage for a picture. --Wrongfilter (talk) 12:26, 6 February 2017 (UTC)[reply]

The references in the Westphal balance article not only give pictures, but explain, in English, how it works. — Preceding unsigned comment added by Wymspen (talk • contribs) 14:29, 6 February 2017 (UTC)[reply]

"Exposed: How world leaders were duped into investing billions over manipulated global warming data"

I saw this news article which claims that a June 2015 article published by Science titled ‘Possible artifacts of data biases in the recent global surface warming hiatus’ was rushed to publication, used faulty data which exaggerated global warming and was timed to influence the Paris Agreement on climate change. Is there any truth to this or is this sensationalist journalism (or a little bit of both)? A Quest For Knowledge (talk) 21:24, 6 February 2017 (UTC)[reply]

Step one: find it in a reliable source. The Daily Mail is known to fabricate stories. --Guy Macon (talk) 21:51, 6 February 2017 (UTC)[reply]

See ad hominem, Guy. Even the devil can quote scripture. μηδείς (talk) 22:15, 6 February 2017 (UTC)[reply]

Questioning the validity and reliability of a source is par for the course for any person educated in research. The Daily Mail is a publication of low repute, because while they sometimes say true things, they are also known to mislead and make shit up. Guy is completely correct to ask for more reliable sources. This is not ad hominem -- the DM is no man, and when it comes to sources, their prestige, reputation and character are precisely what is being relied upon to establish reliability and authority. You may trust everything you see written on the bathroom wall, but I'll continue to view such missives with skepticism, pending reliable sources ;) SemanticMantis (talk) 23:10, 6 February 2017 (UTC)[reply]

Well, SM, Guy's thought process was, The Sun is evil, so what it quoted was false, even though the source was named. Given the Sun is People, that's the essence of ad hominem. μηδείς (talk) 00:50, 7 February 2017 (UTC)[reply]

Are you a mind reader? If not I don't see how you know what Guy Macon was thinking. And unless you're a mind reader, you seem to have came up with a strawman. It seems far more likely Guy Macon was doing what, as SemanticMantis has said, any competent person will do. Evaluate the source. If the source is known to be unreliable, then there's no reason to assume what is quoted is true. Note that this doesn't mean it's definitely false, but simply that we have no particular reason to think it's true. Therefore, unless someone can find a better source, there's not much point researching further. I could likewise claims global warming is a Chinese conspiracy. However if I don't have any actual evidence for this claim, there's zero reason for anyone to take my claim seriously, research it further etc. If you want to go further, this also seems to be a case of extraordinary claims require extraordinary evidence, so it's reasonable to assume it's probably (but not definitely) false based on the lack of any real evidence (since as said, Daily Mail isn't really evidence). Nil Einne (talk) 01:32, 7 February 2017 (UTC)[reply]

In my case, Medeis/μηδείς does not have the ability to read my mind despite multiple attempts to do so. If I had wanted to say "The Daily Mail is known to fabricate stories, thus this particular story is fabricated" (a logical fallacy) I would have said so. Instead I said "The Daily Mail is known to fabricate stories. Find the same story in a reliable secondary source so I can evaluate it". I am still waiting for that source.

The editorial at reason.com[1] (which, while openly biased towards libertarianism, does have a good reputation for accuracy and fact checking) reports what the Daily Mail claimed, but goes on to mention "a February 2016, Nature Climate Change published an article by a prominent group of researchers led by Canadian climate scientist John Fyfe" and "a new study published in Science Advances just last month by the researchers from the Berkeley Earth group", noting that "the Daily Mail article failed to mention [this] study which found that the revised NOAA temperature data are accurate." --Guy Macon (talk) 02:57, 7 February 2017 (UTC)[reply]

I would go a bit further, and say that it's also obvious on its face that the Daily Mail writer (and the editor who ran the "story") are conspicuously and woefully ignorant at best, and deliberately deceptive and inflammatory at worst. To wit, the Daily Mail's version of historical context:

"The scandal has disturbing echoes of the ‘Climategate’ affair which broke shortly before the UN climate summit in 2009, when the leak of thousands of emails between climate scientists suggested they had manipulated and hidden data."

which sounds damning indeed, as long as you don't actually complete the sentence honestly with something like ...which turned out – across at least eight independent investigations – to involve only trumped-up charges by climate change denialists, and no wrongdoing whatsoever by any scientist. If this case does have "echoes" of Climategate, it's probably not in the way that the Daily Mail really would like us to think. They nail their colors to the mast later on in the article, declaring "It's not the first time we've exposed dodgy climate data, which is why we've dubbed it: Climate Gate 2", again crucially omitting any mention that all the Climategate (1?) data was confirmed, and all the scientists exonerated.

And the outcome of the original Climategate controversy isn't hard to discover. It's in the lead of the freakin' Wikipedia article. A writer who omits that information (and presents the original Climategate controversy as representative of actual or probable wrongdoing) would have to be working very hard indeed to maintain such a high level of genuine ignorance—but is much more likely simply dishonest. TenOfAllTrades(talk) 03:48, 7 February 2017 (UTC)[reply]

The sources I've mentioned below great criticsm of the story but perhaps one of the more obvious flaws beyond the misleading claims about Climategate is the use of a misleading image comparing two graphs but using different baselines. They've since "corrected" this simply by noting one graph is offset from there other. This is criticised in many sources (including the ARSTehnica source linked below) but [2] is probably one of the simpler ones. Nil Einne (talk) 06:38, 7 February 2017 (UTC)[reply]

Ars Technica. A Quest For Knowledge (talk) 22:06, 6 February 2017 (UTC)[reply]

There are a few news sites parroting the same story, but it all goes back to one guy, Dr. Bates, crying foul play, but not really suggesting why or how, other than that they didn't follow a set of plans he was drawing up. See below for more info. SemanticMantis (talk) 22:14, 6 February 2017 (UTC)[reply]

(EC) Here is the original Science article in question [3]. Here are the 182 articles that currently cite it [4]. I can find no serious scholarly complaints about the basic data used in the paper, though there is some disagreement on how to best analyze it and what conclusions should be drawn - very minor stuff, and completely normal for the field, not at all indicative of foul play. As for the accusation "It was never subjected to NOAA’s rigorous internal evaluation process" - who cares? Internal review is not what makes science authoritative - peer review (and time) is. The fine folks at Science have given this work their approval after their own external peer review.

Note that there is no specific complaint offered by Dr. Bates, other than the data wasn't internally reviewed, and that he calls it "misleading". Normally, if a scientist has a problem with the data or conclusions drawn by another group of authors, they write a response article in that same (or sometimes a different) journal. If the editorial board finds the complaints meritorious, they publish the critique, and sometimes solicit the original authors and give them a chance to write a rebuttal. The fact that Dr. Bates offers no specific problem and seemingly has not pursued the normal channels, but instead runs to the tabloids does not paint him in a very credible light, despite his affiliation. Also, NOAA does plenty of quality control and quality assurance for every data product they offer, Dr. Bates' "internal review" is not part of that. NOAA is currently a world leader in developing and deploying QA/QC for large scale data, see e.g. here [5] for a feeling on that, or I can give further refs on that if you're interested.

So - this kerfluffle is all just days old, and good references are lacking. Seeing no serious critique in the published literature, and noting that (to the best of my knowledge) Dr. Bates has not published a critique in any scientific venue, my opinion as a scientist operating in an adjacent field is that, lacking any more credible evidence of foul play, we should continue to extend our trust in the practices in place at Science, which is probably the best scientific journal in the world, and it very rarely has any problems with any of their publications. By all means, keep your eye out for something damning, but this looks like nothing more than a disgruntled NOAA chap (who has a clear conflict of interest, by the way) who's found a receptive audience for a witch hunt. I wish my colleagues at NOAA well, this is a bad time to be a public scientist in the USA.

Finally, experts and politicians both give no undue weight to any one publication. This Karl paper was not the only one out, there were many available at the time. These two [6] [7] are also both about the "pause", were also published in 2015, and can help you understand some of the differing viewpoints on the quality of the data and how to interpret it. SemanticMantis (talk) 22:14, 6 February 2017 (UTC)[reply]

The most interesting claim is "This newspaper has learnt that NOAA has now decided that the sea dataset will have to be replaced and substantially revised just 18 months after it was issued, because it used unreliable methods which overstated the speed of warming." This is definitely a put-up-or-shut-up claim; either NOAA will revise the dataset or it won't. And scientists will look at both datasets and see if the revision is a hasty snow job by Trump appointees or actually has some reason. Until then, there's no great urgency to predict what we'll see ... we know we'll be doing absolutely nothing good about global warming no matter what. Wnt (talk) 00:15, 7 February 2017 (UTC)[reply]

This is a canonical example of a red herring. NOAA continually updates its data sets, as does every other operational center (Hadley Centre, ECMWF, etc etc). Shock Brigade Harvester Boris (talk) 01:55, 7 February 2017 (UTC)[reply]

Indeed as far as I can tell, the claim is simply referring to ERSSTv5. While the time frame between ERSSTv5 and ERSSTv4 seems a bit short (compared to ERSSTv4 vs ERSSTv3b for example) there could be various reasons for that. Notably the fact that ERSSTv5 is coming is not some shocking new discovery by the Daily Mail. It's upcoming release has been noted well before this, see e.g. this from June 2016 [8] which specifically mentions a 2017 release target. Nil Einne (talk) 02:05, 7 February 2017 (UTC)[reply]

[9] is a direct response to the Mail on Sunday story. Nil Einne (talk) 01:48, 7 February 2017 (UTC)[reply]

I tried a Google search for "Pausebuster" (which is what the Daily Mail says the "scandal" is called, although they like the term "Climategate 2" better) and I see it mentioned by Fox News, Breitbart, the Washington Times, "What's up with that," and Reason. As a rule, if a story doesn't bounce out of the echo chamber into mainstream news, then it cannot be important. Mind you, the Daily Mail reporters have made it seem pretty important. Thanks to SemanticMantis and Nil Einne for pointing out it does not really say anything. No doubt some editor will create an article which I do not think is justified unless it attracts mainstream media attention and we will have adequate sources to write an informed article. TFD (talk) 02:01, 7 February 2017 (UTC)[reply]

Another blog response this one dealing more with the processes than the science [10]. That links to [11] which also deals mostly with the science. In the interest of full disclosure, I also came across this response on Judith Curry's blog to the first blog and other things [12]. Nil Einne (talk) 02:09, 7 February 2017 (UTC)[reply]

Note that you can tell it's not a scientific article from the title alone: "Exposed: How world leaders were duped into investing billions over manipulated global warming data". Words like "exposed" and "duped" do not belong in a scientific paper (unless "exposed" was used in a context like exposure to UV light). Also, a scientific paper wouldn't concern itself with what world leaders are doing with money (unless it was an economics paper), it would stick to the facts in question. StuRat (talk) 02:34, 7 February 2017 (UTC)[reply]

I would think the fact that it wasn't in a scientific journal might also be relevant. Shock Brigade Harvester Boris (talk) 03:12, 7 February 2017 (UTC)[reply]

It could have been copied from a scientific journal. StuRat (talk) 15:22, 7 February 2017 (UTC)[reply]

Given the fact that the Daily Mail is well-known for stealing stories from other sources, rewriting them to be more lurid and clickbaity, then passing them off as original work,[13][14] just for fun I sometimes try to figure out where the Daily Mail stole a story from. in this case, the original sources seem to be the events in this timeline[15] and possibly an early draft of this press release.[16] --Guy Macon (talk) 03:16, 7 February 2017 (UTC)[reply]

Old style fake news, global warming skeptics have always been tolerated by society. It's only because Donald Trump is seen to have gone too far with inventing false stories that society has decided that the truth actually does matter. So, perhaps this sort of news reporting will stop thanks to Donald Trump. Count Iblis (talk) 03:53, 7 February 2017 (UTC)[reply]

"global warming skeptics have always been tolerated by society?" that's a very odd claim. Who is this "society" you're referring to? In the US " only 27 percent of respondents agree with the overwhelming scientific consensus that human activity is the main cause of climate change".[17] That's nearly a third of society there that just don't believe the scientists. They don't tolerate climate sceptics - they fully support them. Richerman (talk) 13:21, 7 February 2017 (UTC)[reply]

It seems no one has linked Bates blogpost yet [18]. Back to criticism, I came across [19] (I also linked above), [20], [21] [22]. There has also been media response [23] [24]. There have been various political responses, but one of the more interesting ones that directly relates to the Daily Mail's claims is from those involved in the Paris negotiations who've said the paper wasn't particularly significant [25]. So if you accept that, even if the Mail's claims over what NOAA were trying to do were true, NOAA still failed. And actually Daily Mail specifically said "Official delegations from America, Britain and the EU were strongly influenced by the flawed NOAA study as they hammered out the Paris Agreement" and "The flawed conclusions of the Pausebuster paper were widely discussed by delegates at the Paris climate change conference" which is not supported by comments from those involved, who if they cite anything in particular it's IPCC AR5. (Edit: If you believe that the politicans are lying about what influenced them and what they discussed, then I'm not sure there's any reason to make a big deal over what NOAA said anyway. Maybe they just don't care about the science and are just following what CHINA are telling them.) Also I got one or two of my links from [26] so I'll include it even if I'm not sure it has anything else useful. Nil Einne (talk) 06:38, 7 February 2017 (UTC)[reply]

It looks to me like the Daily Mail grossly exaggerated an actual problem. My take on it is that Bates did some whistleblowing because the authors of a paper ignored some procedure he had set up for data documentation and archiving. They should have followed those procedures and if they had the results they got at the end would have been better founded and might have differed I think by as much as 0.03°C. Important for climatology but not something that invalidated their conclusions, but even so it was bad practice. I applaud that Bates did the whistle-blowing when he couldn't get satisfaction within the organisation and I am very sad the new administration will clamp down on anything like that after Obama expressly encouraged it. NOAA got badly hammered for this by the oversight committee which had someone in charge who was being paid by the oil industry.. I guess the committee would have found something else to harass climate scientists with if not this but there's no point in giving ammunition to someone who wants to discredit you.

You can see the discrediting starting in the very first diary entry by the chairman of the oversight committee: "June 4, 2015: NOAA scientists, led by Mr. Thomas Karl, published a study in AAA’s Science magazine. The study refutes previous scientific data that there existed a halt of global temperature increase since 1998." Climate scientists never said the warming had stopped, just that it wasn't increasing as fast as before and the paper was saying the rate was close to the previous rate if one applied recent corrections that took account of differences of how data was collected. Dmcq (talk) 10:00, 7 February 2017 (UTC)[reply]

For anyone still interested, Snopes has dissected the Mail's dissembling here. If you're interested in the technical aspects rather than the politics, see Zeke Hausfather's article here. Shock Brigade Harvester Boris (talk) 02:15, 9 February 2017 (UTC)[reply]

Resolved

Thanks to everyone for their answers. :) A Quest For Knowledge (talk) 17:55, 9 February 2017 (UTC)[reply]

MTHFR polymorphisms

I wonder if there's a list of all polymorphisms for MTHFR[27] gene? Perhaps with some clinical correlates also? How many of them are out there? Wikipedia gives 24, I remember reading somewhere it was 42 although I cannot recall the source. Thanks, --AboutFace 22 (talk) 22:18, 6 February 2017 (UTC)[reply]

First, let's spell out your link to Methylenetetrahydrofolate reductase... next we'll click on the link to Entrez in the infobox at right, and click on Variation: [28] ... ClinVar lists 208 variants. It would take me some time to make sense of all that data! Wnt (talk) 00:08, 7 February 2017 (UTC)[reply]

What is wrong with my spelling :-). I could not find 208 variants though. Anyway, many thanks. --AboutFace 22 (talk) 12:00, 7 February 2017 (UTC)[reply]

@AboutFace 22: That's odd... for some reason the top link to ClinVar now takes me to the dbVar results, which were fewer. But this link [29] goes directly to the 208 results I saw before. I'm not sure if that link changed for some odd reason or if I did more scouting around than I remember. Wnt (talk) 12:16, 7 February 2017 (UTC)[reply]

@Wnt, you are an Angel. Thank you very much. In an hour and the half I am schedule to make a presentation on one of the issues related to MTHFR gene. Yes, now I got the table and all the information needed. Thanks, --AboutFace 22 (talk) 13:29, 7 February 2017 (UTC)[reply]