Wikipedia:Reference desk/Archives/Science/2015 December 12

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December 12[edit]

Alcohol's effect on CNS[edit]

We all know that alcohol affects the central nervous system slowing down reactions and muscle movements etc but does this mean it also has an effect on involuntary movements such as breathing or heart beats? And I mean in the short term, not long term problems as a result of drinking. And also assuming the person has no log term health problems. 2A02:C7D:B901:CC00:1492:CF54:6C39:5046 (talk) 10:09, 12 December 2015 (UTC)[reply]

See Alcohol intoxication#Acute alcohol poisoning. Excessive alcohol consumption can indeed cause fatal respiratory depression. Tevildo (talk) 10:46, 12 December 2015 (UTC)[reply]
Methanol is toxic, ethanol, by overdose only. --Hans Haase (有问题吗) 00:21, 15 December 2015 (UTC)[reply]

Do insects learn?[edit]

We know that cats learn. I mean a very basic thing: we notice that at one time, a cat does something in one way, but later, it chooses to follow a different way to do that very thing. For example, it may learn to recognise certain people, or it may learn how to open doors, or it may learn a certain location that helps achieve certain ends, or it may learn actions to avoid in a certain location or in presence of certain people. We know that cats do the same things differently at different times, based on their unique experience (the point of uniqueness of behaviour is important: for one aspect, since it is impossible to pre-enumerate every possible behaviour, that implies that a change in behaviour corresponds to a real change in the structure of their brains, it doesn't boil down to a mere illusion of observation). Do we know the same, at least in some marginal cases, about insects? Can they learn at least sometimes? Or they never learn at all? I know that questions about consciousness could be debated to no end, but this question is not about consciousness. Thank you. - Evgeniy E. (talk) 10:20, 12 December 2015 (UTC)[reply]

We don't have an article specifically on insect learning, but see Ant#Learning and Bee learning and communication. This paper might also be useful. Tevildo (talk) 11:19, 12 December 2015 (UTC)[reply]
Thank you, much appreciated. I edited the place where I looked for the answer. - Evgeniy E. (talk) 12:55, 12 December 2015 (UTC)[reply]
From those example, you can see that insect "learning" is rather limited, more what we would call memorization, like memorizing the path to food. However, more fundamental learning, like a new language (say used by another species), might well be beyond them. Cats and dogs, on the other hand, are able to learn at least a few words of our language. StuRat (talk) 06:40, 13 December 2015 (UTC)[reply]
The essential difference between learning to respond to a certain type of flower (as bees can do) and learning to respond to a certain spoken word (as dogs can do) is not obvious to me. Looie496 (talk) 12:24, 13 December 2015 (UTC)[reply]
For a computer programming POV, it's the difference between loading more data into an existing program, like the location of a food source, versus writing a new program, like one to communicate in a new language. For example, an electronic microwave oven has some ability to remember, in that you punch in the temperatures and times for each cycle, and it follows those commands. But you're not going to get a microwave that isn't designed for speech recognition to spontaneously understand you (even if we assume a microphone was attached to it). From a biological POV, remembering a location requires far fewer nerve cells and connections to establish, and falls into the category of "instinct" (the instinct to locate food, remember it's location, and return to that location with others, for example). But to learn something completely novel requires more brain than they have. StuRat (talk) 21:56, 13 December 2015 (UTC)[reply]
They do learn - in almost all the ways you mention for a cat. I'm not entirely sure whether you meant the question to relate to invertebrates in general, or limited to insects, so I will stick to insects for the moment. You will find some of their learning abilities described in Pain in invertebrates#Conditioned avoidance and Pain in invertebrates#Cognitive abilities. Drone bees will learn to suppress extending their proboscis when this results in an electric shock. Fruit flies learn to avoid areas that are too warm (like my cats in summer!). Bees are able to form concepts - a method of advanced learning. Both ants and bees show evidence of numeracy (to the best of my knowledge, this has not been shown in cats!).DrChrissy (talk) 12:57, 13 December 2015 (UTC)[reply]
Thanks for all additional examples. ;) Well, now I actually wonder whether there are massive groups of animals, who have a brain or at least a nervous system, but cannot learn. ;) (In the sense of developing unique behaviour in response to unique experience). But this question, I suppose, is much more difficult to answer. ;) Most likely, this one can't? ;) - Evgeniy E. (talk) 21:08, 13 December 2015 (UTC)[reply]
Not really all that difficult a question to answer - but you need to define what a "brain" is.DrChrissy (talk) 00:37, 14 December 2015 (UTC)[reply]
I could evade this need by relaxing the criteria to "at least a nervous system" and never-minding the level of its complexity. There is a problem, of course, with the fragment of "massive groups", no-one knows what makes a group "massive". ;) I don't know why I was interested in this follow-up question, so now I preferred to not give any additional specification. Anyway, I got what I needed when I asked the original question. ;) (Now I am confused, though: proving absence of learning in different obscure animals should seem impossible; therefore, there ought to be no references to such proofs anywhere in the Internet or beyond; therefore, the question ought to be difficult to answer). Again, thanks everyone who helped. ;) - Evgeniy E. (talk) 01:28, 14 December 2015 (UTC)[reply]
Belated response to your closing question 3 posts above: this one apparently can, if you count forming long-lasting memories as 'learning.' {The poster formerly known as 87.81.230.195} 185.74.232.130 (talk) 18:19, 14 December 2015 (UTC)[reply]

Name of physical property when solid object touches water[edit]

If you touch a water bubble with a pencil, the water seems to stick to the pencil. How's this stickiness called?--3dcaddy (talk) 19:08, 12 December 2015 (UTC)[reply]

I think the answer is "Surface tension". 80.44.164.220 (talk) 19:14, 12 December 2015 (UTC)[reply]
No, the answer is Dispersive adhesion. Surface tension is a different phenomenon. There's quite a good explanation of the physics behind what I believe you're looking for at Wetting. ‑ Iridescent 19:16, 12 December 2015 (UTC)[reply]
Isn't surface tension different, but pretty close to the dispersive adhesion you cite? You have cohesion, between molecules of the same substance. And you have adhesion, between molecules of the same substance. --3dcaddy (talk) 21:06, 12 December 2015 (UTC)[reply]
It's all part of the same suite of phenomena caused by the types of intermolecular forces present; in water this is primarily hydrogen bonding, and the same kinds of processes are also involved in things like meniscus and capillary action. --Jayron32 21:51, 12 December 2015 (UTC)[reply]

What is enq in the following context?[edit]

I found an exercise in the google: A patient of heart rate of (120/min) his pressure is 150/90 mmHg. Calculate the work done by the left ventricle for 2 seconds.

Sol:-
W= p x ∆V
P= (150+90)/2 = 120 mmHg.
=120 x 1330 = 1.6 x 105 dyne/cm2
∆V = 120/60 sec x 80 ml =160 ml/sec.
W=120 x 1330 x 160 =2.6 x 107erq/sec
W/2sec = (120 x 1330 x 160) x 2=5.2 x 107 erq/sec.

92.249.70.153 (talk) 21:43, 12 December 2015 (UTC)[reply]

Looks like a typo for erg. DMacks (talk) 21:49, 12 December 2015 (UTC)[reply]
More like a scanno. —Tamfang (talk) 22:27, 12 December 2015 (UTC)[reply]
It must be an extremely old article. The erg hasn't been in common use outside astrophysics since about 1960. Tevildo (talk) 23:26, 12 December 2015 (UTC)[reply]

Well, just for the exercise: 120 mmHg (average) x 133.322387415 (Pa/mmHg) = 15999 Pa = 15999 N/m2 = 15999 kg m-1 s-2. Because one dyne = g cm /s2, it gets a 10-5 conversion factor, which then is cancelled by cm2 to a 10-fold difference. (It is right around now one remembers that the incursion of CGS units removes much of the vaunted advantage of the so-rational-and-easy-to-work metric system...) Unchanged: ∆V = 2 [beats] / s x 80 ml = 160 ml/s = 0.16 l/s. So W = 15999 Pa x 0.16 l/s = 2560 kg l m-1 s-3 ... say waat? ... the assumption, not stated, is that 1 kg = 1 l for blood, so that's 2560 kg2 m-1 s-3. This is then multiplied by 2 s for 5120 kg2 m-1 s-2 = 5120 J/s - this is multiplied by (1000 g/kg)2(1 m/100 cm)2 for a net 104 conversion factor. And now that I have refreshed my recollection of what I think of cgs, I shall endeavor once more to forget it... Wnt (talk) 15:09, 13 December 2015 (UTC)[reply]

When and how Saddam Hussein destroyed his WMD?[edit]

It's clear that Saddam had at some point MDWs, but none were found after the Iraq invasion. What happened to his MDW program and arsenal? — Preceding unsigned comment added by Scicurious (talkcontribs) 23:16, 12 December 2015 (UTC)[reply]

See United Nations Monitoring, Verification and Inspection Commission and Iraq Survey Group (and weapons of mass destruction, WMD, as well). According to the second article, the survey had "not found evidence that Saddam possessed WMD stocks in 2003". To answer your question, it didn't exist. Tevildo (talk) 23:25, 12 December 2015 (UTC)[reply]
That does not answer my question. I am not disputing that there were no MDW weapons in 2003. But what happened to the MDW program between the last use and 2003? Did he use all weapons that were produced? What happened to the factories? Is all buried somewhere? --Scicurious (talk) 23:55, 12 December 2015 (UTC)[reply]
WMD conjecture in the aftermath of the 2003 invasion of Iraq summarizes the various conspiracy theories about the issue. The official reports (mentioned above) found no evidence that Saddam had a working chemical weapons programme, so, again, "it didn't exist" is the answer best supported by the evidence rather than speculation. Tevildo (talk) 01:18, 13 December 2015 (UTC)[reply]
The conjectures above are rather about the recent events pre-2003. And it might be a fact that in 2003 there were none. I am not disputing this. But it's also a fact that back in the 80s or 90s, he had some, and has even used them. So what happened to the WMD program, stockpile, scientists? I am asking way before Bush + Blair accused Saddam of having WMDs. --Scicurious (talk) 02:41, 13 December 2015 (UTC)[reply]
We do have the more general article Iraq and weapons of mass destruction. -- ToE 03:30, 13 December 2015 (UTC)[reply]
We found his stockpiles of chemical WMDs used previously. Not sure we found the aluminum tubes used for centrifuges. We had the same evidence of a nuclear program that we have for Iran and North Korea. When the U.S. invaded Iraq, all CIA analysts agreed that he had a nuclear weapons program but disagreed about whether specific components (so-called "dual use" items) were used in the program. This includes Valerie Plame. We see things like chemical weapons used in the Syrian Civil war so they exist. --DHeyward (talk) 03:54, 13 December 2015 (UTC)[reply]
Here is a 2005 Report to the President of the United States: The Commission on the Intelligence Capabilities of the United States Regarding Weapons of Mass Destruction. This 600 page book contains over two hundred pages of unclassified, public information about Iraq's purported weapons program - as reported by informed expert witnesses and endorsed by numerous United States senators. The report explains what the Senate commission believed to be factual, with respect to the existence of weapons of mass destruction in Iraq.
Among the many specific statements in this report: chemical weapons facilities did not exist. Evidence of chemical weapons facilities also "did not exist." (Page 121). Biological weapons did not exist. Evidence of biological weapons also "did not exist" - it was "fabricated" (page 80, page 108). The same applies to the nuclear weapons program (page 3); the intelligence analyses of the purported Iraqi program were technically flawed and based on poor intelligence "tradecraft" (page 66); although further details about our Government's ability to conduct nuclear program monitoring are not published because they contain classified information (page 305).
In short, the United States Senate (including Republican senator John McCain) believed that there were no weapons of mass destruction and any evidence of such weapons did not actually exist when President Bush was briefed. Much of the report follows up on these bold assertions with factual data, paper trail investigations; the report outlines proposed motives and other causal factors for these incorrect and false intelligence reports; and makes recommendations for ways to prevent this problem in the future.
If this voluminous information does not satisfy your curiousity, maybe you can rephrase your question. Are you looking for information as reported by some other source? If so, which source?
If you do not believe the (unclassified) factual assertions published by the United States Senate, then whose factual assertions would you rather trust? We can find lots of other resources with lots of other points of view; some other authors believe different facts to be true, and we can point you toward those authors; but at some point, you have to believe somebody, or else resign yourself to a sort of solipsistic ambiguity about all factual information.
Nimur (talk) 04:21, 13 December 2015 (UTC)[reply]
Here is one more point of view: Disarming Iraq (2004), by Hans Blix. In this book, Blix (who directed weapons inspections for the United Nations UNMOVIC in Iraq) states: "When our commission was established by a Security Council resolution in December 1999, the Council had recognized that there might still be weapons of mass destruction (WMD) in Iraq, despite the fact that a great deal of disarmament had been accomplished through UN inspections after the end of the Gulf War in 1991. In November 2002, a new round of inspections had been initiated to resolve key remaining tasks in the disarming of Iraq."
UNMOVIC was tasked to oversee Security Council Resolution 687, and its successor Security Council Resolution 1284. This called for Iraq to unconditionally accept the destruction, removal, or rendering harmless, under international supervision, of specific weapons. UNMOVIC actually reported that Iraq was largely in compliance with these resolutions, and there were specific action-items that were called out for escalation. The State Department reported that UNMOVIC reported that Iraq was not in compliance. Depending on whose report you read, you get a different portrayal of the facts, which is exactly what the problem was. The factual evidence was not presented to decision-makers, and consumers of factual information did not closely and critically scrutinize the facts. (Perhaps, as the Senate report I linked above alleges, the decision-makers did not want to be fully-informed). Quoting Blix: "The military invasion of Iraq was all but announced and here we were at the UN sketching a peaceful way to try to ensure the country’s disarmament!"
Nimur (talk) 05:20, 13 December 2015 (UTC)[reply]
Some people missed the point of the Q, that at one time there was no question that Saddam had WMD's, he even dropped poison gas on a Kurdish village (Halabja chemical attack). Then, by the US invasion of Iraq, they had apparently all disappeared. The "expert speculation" I heard was that he had them destroyed, to comply with the UN, but did it in secret, so as to keep his enemies, such as Iran, guessing. StuRat (talk) 05:42, 13 December 2015 (UTC)[reply]
I believe I saw somewhere that he got rid of then between 1991 and 1993 just after the Gulf War. Sorry I have to do other things and can't look i up. Dmcq (talk) 09:57, 13 December 2015 (UTC)[reply]
StuRat DMCQ got exactly the point of my question.
I don't know why others insist on the 2003 situation. I have no doubt there were none on 2003. And although it's interesting to see it confirmed with sources, the question is about what happened (to the factories and stockpile) between the documented use of the WMDs, and, the documented confirmation there were no WMDs anymore. --Scicurious (talk) 13:09, 13 December 2015 (UTC)[reply]
Maybe you are choosing not to read the resources I linked; the UN monitored and documented the disarmament subsequent to the 1991 Gulf War, and they published all their reports. The UN continued to monitor and document to ensure that new activities in Iraq did not violate the agreed-upon rules. The process was difficult and not always conducted on friendly terms, but it did take place, and the UN published details extensively. (UNSCOM document archive; UNMOVIC document archive). This stuff is free and available on the internet: you don't need special connections or privileges to see it; you don't need to file paperwork with your government representative to review the bulk of the documentation; it is largely unclassified and available for you to inspect (you don't need any "Internet Activists" to leak it to you). For example, here are a random assortment of official press photos of equipment being destroyed or removed during UNSCOM inspections in the early 1990s. Here's one dramatic photo that is easy for a non-technical reader to understand, specifically of UNSCOM watching 122mm rockets being burned. Everything is published for you to independently review and evaluate. With which part of this extensive documentation are you misunderstanding or disagreeing, or just choosing not to look at?
I can only assume that your braindead refusal to look at these facts is part of your political agenda to ignore facts. This specific problem of intentionally ignoring documented reality has been a historical problem and you are perpetuating a distortion of fact that significantly contributed to the casus belli in 2003.
Perhaps, if encyclopedic sources are too dense for you, you will understand a little better after considering Aaron McGruder's lampooning of the situation from the Boondocks series episode, "A Date With The Health Inspector".
Nimur (talk) 18:34, 13 December 2015 (UTC)[reply]
Maybe you are choosing to ignore the maning of the word 'hidden'. Hidden means they cannot be found, otherwise it's not hidden. That's why the UN could find all the weapons. That does not mean Saddam didn't keep some. --Scicurious (talk) 19:57, 13 December 2015 (UTC)[reply]
You are essentially parroting the argument put forward by Defense Secretary Donald Rumsfeld. If you are doing this in an intentional fashion, for the sake of playing the apologist, your position has the disadvantage that the present year is 2015, and his argument has been discredited by more than ten years full of new factual information. If you are parroting his argument simply because you are uninformed, you might wish to read some more history. In either case, unless you are asking for scientific references on this topic, this discussion probably does not belong on the Science Reference Desk. Nimur (talk) 20:40, 13 December 2015 (UTC)[reply]
To put things a different way, your last comment is very confusing. You initially wanted to know what happened to those WMD which did exist in 1991 and before, to 2003 when they did not exist. While some of the above answers may have been offtopic; even if you didn't initially understand Nimur's answer, the second version of the made it clear that their sources did provide an answer to your question of what happened to those weapons that did exist.

You now bring up "hidden" weapons. Are you trying to ask when the hidden weapons were destroyed? If you are asking this, what evidence do you have for these hidden weapons?

Are you trying to say there were still weapons in 2003 and although these were never found they did exist and were simply hidden? If so, not only do are you coming up with a conspiracy theory apparently without support, your complaints about any of the older answers now seem unfair since these answers did address this claim, even if it hadn't yet been made.

Are you trying to say that the suggestion there were WMD in 2003 wasn't inaccurate at the time since there may have been hidden WMD? If so, again you'll need to provide some refs for the suggestion there was good reason to believe he may have hidden WMD (which would need to be more than Saddam was perfectly willing to do something like that). As again the evidence from sources thus far, particularly from Nimur but also others (again including some of those you complained about) suggests there was no good reason to believe there was a hidden program in 2003.

Nil Einne (talk) 04:24, 14 December 2015 (UTC)[reply]

There are two questions: Did he have WMDs? followed by Did he have a WMD program? It is easy to conflate those two questions. The same would be true for Iran, Pakistan, North Korea, Israel, South Africa, etc, etc. While the existence of actual WMDs was circumspect with many doubters, the belief that he had a program was not. Virtually everyone believed he was developing WMDs and that is in the Senate report. It was the reason Clinton bombed him and Valerie Plame even believed he had a WMD program. CIA analysts disagreed on specifics like yellow cake and aluminum tube but not the overall assessment that Iraq was trying to obtain and build WMDs in violation of the UN sanctions. --DHeyward (talk) 05:32, 14 December 2015 (UTC)[reply]
The later question seems irrelevant to anything discussed in this thread (note the OP said hidden WMD, not hidden WMD programme) so not sure why you want to take it even more offtopic. Of course what people may or may not have believed because "Collectors and analysts too readily accepted any evidence that supported their theory that Iraq .... was developing weapons programs, and they explained away or simply disregarded evidence that pointed in the other direction" or whatever also seems less important that what the evidence now suggests was really going on, but again this all seems terribly off topic. Edit: I see the OP did mention something about a MWD (sic) program in some earlier comments. But their question was what happened to it, not what people may or may not have believed happened to it in 2003, so your comment still remains off-topic. Also they seem more interested in the actually WMD stockpile and why few or no more were produced, rather than the a WMD program in the theoretical sense. Nil Einne (talk) 13:28, 14 December 2015 (UTC)[reply]
DMCQ above is correct. The short answer to the OP's question is in Hussein Kamel al-Majid's 1995 statement- "I ordered destruction of all chemical weapons. All weapons—biological, chemical, missile, nuclear—were destroyed." There was not much real doubt after that that Iraq did not have WMDs.John Z (talk) 02:24, 15 December 2015 (UTC)[reply]