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October 5[edit]

Is this item from "Geek" safe to use?[edit]

Someone I know ordered this thing for me from "Geek" and I was curious if it's really safe to use. Their idea was that it would be helpful for when I use my phone's GPS navigation feature, but I question whether or not it's safe to attach something like that to the steering wheel considering there is an airbag in the steering wheel. It shipped directly from China, so the manufacturer may have dodged United States Consumer Product Safety Commission regulations. Thoughts? PCHS-NJROTC (Messages) Jesus Christ loves you! 02:50, 5 October 2015 (UTC)

Attaching anything to the wheel that could interfere with emergency steering (and this definitely looks like it could) is unwise. The airbag issue seals the deal. Shock Brigade Harvester Boris (talk) 03:37, 5 October 2015 (UTC)
It's fine to use when the vehicle is stationery, but in the UK it would probably be considered illegal to use it when driving, and, of course, it would be very difficult to use on curved roads. For navigation, I mount my phone just behind the steering wheel. Dbfirs 08:39, 5 October 2015 (UTC)
There's a 2012 patent , looks pretty much the same. So probably a cheap copy (assuming the patent made it to market). No safety guarantees here... Ssscienccce (talk) 15:28, 5 October 2015 (UTC)
It seems that now everybody wants to strap an iPhone or iPad to the controls! A wide variety of yoke mounts are available; here's an article from Sporty's (it's a little bit of a promotional piece, but it's brand-agnostic and very informative): Where should I mount my iPad in the cockpit? My vehicle doesn't have a steering wheel or a yoke, so I prefer to strap my supplemental navigation electronics to my leg or on my clipboard; but I know a lot of folks who like to keep their head up. Safety means many things: if a distraction from an electronic device is diminishing your safety, or if the device is interfering in any way with your control, don't use it; if a supplemental electronic information system helps you navigate, or reduces your workload, it can improve safety.
The original question asked whether such a device "dodged" some type of safety regulation. As far as I know, there is very little legislation or government regulation regarding such systems in automobiles; most states are very liberal in allowing owner modifications to the interior of the automobile cabin. Specifically, automobiles are outside the jurisdiction of the Consumer Product Safety Commission (vehicles, including after-market modifications to vehicles, are regulated by the National Highway Traffic Safety Administration and the individual state governments; the regulations are incredibly non-specific, e.g. 49 C.F.R. §567.7 Requirements for persons who alter certified vehicles). As far as airbags, there is some extra legal-ese regarding any alteration that can "make inoperative" the safety feature; if adding a steering-column-mounted electronic device "makes" the crash safety system "inoperative," the installer (not the manufacturer) would be in violation of Federal regulations. In other words, you carry the liability, not the device vendor.
Some consumer groups may make independent, nonregulatory safety guidelines and publish them for manufacturers, in the spirit of safety and conservative judgement; but noncompliance would not be "dodging" any regulation.
As far as using such systems in an aircraft... some very conservative individuals may broadly construe strapping an iPad to a yoke as a "major alteration," and recommend the filing of paperwork; but they're probably not in the mainstream. To help you navigate this question, FAA published Advisory Circular 20-173 Installation of Electronic Flight Bag Components, which provides further references to regulations for crash safety.
Nimur (talk) 13:12, 6 October 2015 (UTC)
The main danger would seem to be in encouraging drivers to take their eyes off the road. AndrewWTaylor (talk) 11:43, 5 October 2015 (UTC)
There's little danger of interfering with the airbag, but I agree it could interfere with steering and distract the driver, so a bad idea for those reasons. StuRat (talk) 22:23, 5 October 2015 (UTC)

Paint color[edit]

What color floor paint do i need to add to black paint to get a dark brown color?-- (talk) 03:27, 5 October 2015 (UTC)

Brown (or light brown, depending on the tone you want). Sometimes the obvious answer is correct. Shock Brigade Harvester Boris (talk) 03:38, 5 October 2015 (UTC)
Cant get brown other wise I would have bought some. Only get red , yelloe or lite browny.-- (talk) 04:00, 5 October 2015 (UTC)
Well, according to our brown article, brown is a mix of Red and green. However, I suspect that if you have black paint, what you will find is that it is going to be VERY difficult to "dilute" the color, you will need a LOT more brown paint than black paint to make dark brown, I suspect sat least a 10:1 ratio, if not even more. Normally to get dark paint you would start with the color you want and add just a LITTLE black paint, probably even less than 10%. In my experience, black paint is very "strong", you only need a tiny amount to change the shade of another paint color quite considerably, and you can very quickly add 'too much' making the mixture very dark. I suspect that even if you have as much light brown paint as black paint, if you mix them together , the result will still be pretty much black. Vespine (talk) 04:44, 5 October 2015 (UTC)
Red plus black should give a shade of dark brown, but sometimes the actual results are significantly different from what colour theory would predict because paints are often not pure shades of their stated colour, so it is important that you try out a tiny sample first to make sure that you get the shade that you want before mixing large amounts. Dbfirs 08:26, 5 October 2015 (UTC)
I agree with Vespine, adding paint to black is not the way to go, you'll end up paying more and with more paint you can't use. imho... Ssscienccce (talk) 00:27, 6 October 2015 (UTC)
So shall i get the lite brownie and add some black till i get the rite shade??-- (talk) 01:54, 6 October 2015 (UTC)
How much paint are we talking about? Are you painting a picture or are you paining a whole fence? Can you do a trial first with just a small amount of paint to see what the result looks like? That would be your best bet otherwise you can ruin a lot of paint if you just start mixing it in bulk. Without seeing the paint and actually trying it, no one here will be able to confidently tell you if any trial you attempt will result in something you think is suitable shade of brown for whatever purpose you need it. Vespine (talk) 01:58, 6 October 2015 (UTC)
Well as i asked in my question about 'floor' paint, it is floor paint. So Im painting a ? ...... floor. Area 3 sq ft (approx) — Preceding unsigned comment added by (talk) 02:06, 6 October 2015 (UTC)
Lol you did indeed, sorry, we call it "bloke blindness" :).. 3ft square is quite small for a floor, it really depends how important is it to you to get the color right. Any method you chose is going to involve a little trial and error. Vespine (talk) 02:41, 6 October 2015 (UTC)
  • The standard instruction is to make orange from red and yellow, then darken it to brown by adding black (or deep blue, with white to lighten it if necessary). If you first add red to black you will get maroon, which you can lighten with lots of yellow. If you add black and yellow you will get an olive color that you can move towards brown by adding lots of red.
The olive and maroon routes are not advisable unless you have a lot of yellow and red to spare. The problem is that if you start with too much black, it is hard to lighten without adding a lot more red or yellow. So the safe bet is the standard one: start with an orange made of half red and half yellow then slowly add black to darken. μηδείς (talk) 17:11, 6 October 2015 (UTC)
I can get the Ronseal terra cotta which is a bit like orange. If I mix that with black will that give dark brown?-- (talk) 17:24, 7 October 2015 (UTC)
Where are you getting the paint? In the US one would normally go to the hardware store, get sample color cards, find the shade that most closely matched the desired color, go back to the store, and ask them to mix it. I assumed from the above that you had a primary red and primary yellow available, as well as a lot of black. In that case, making orange, then darkening it with black would be the normal procedure. A little white or blue would halp if you found the brown was to darrk or red.
But it is impossible to give specific advice over the internet, because we don't see what you have and are not there as you mix it. Unless you are trying to restore an antique, what is the worst that could happen? You'll just have to do trial and error. But I will repeat that starting with an orange and adding black (terra cotta being a less saturated orange) is better than starting with a can of black and expecting to get to brown by diluting it. μηδείς (talk) 18:51, 7 October 2015 (UTC)
OK that's pretty useful advice. I shall try putting a bit of black into terra cotta. Thanks.-- (talk) 23:15, 7 October 2015 (UTC)

What is the significance of 19 and a bit inches[edit]

Markings on a steel rule.jpg

This steel rule has diamond markings at multiples of just over 19 316 inches. It is not a round value in millimetres either. They must serve some purpose as they are there along the whole length of the rule. The only thing I could think of was maybe something to do with 19-inch equipment racks but I can't think what. Probably not relevant, but there are also similar marks at exactly 16 inches. SpinningSpark 16:40, 5 October 2015 (UTC)

According to SDMB and this site, the markings are standard spacings for engineered lumber. The black marks are at 8/5 of a foot (19.2"). Tevildo (talk) 16:50, 5 October 2015 (UTC)
Right, these marks turn a standard measuring tape into a simple type of modular rule (I can't find our relevant page, see e.g. these products used in masonry [1] [2]). The idea is to have the rule(r) marked in way so as to prevent a worker from having to mess around with mental modular arithmetic, and there is likely another marker at integer multiples of 19.2. SemanticMantis (talk) 17:09, 5 October 2015 (UTC)
Markings on a steel rule 2.jpg
The fifth one should be at exactly at the 8 foot mark, according to Tevildo's second link above. Alansplodge (talk) 18:49, 5 October 2015 (UTC)
(Yes, 5*19.2 inches = 96 inches = 8 feet :) SemanticMantis (talk) 19:06, 5 October 2015 (UTC)
Yes, there is a mark at exactly 8 ft. This is a multiple of 16" as well of course. The same mark is used for both on this make of rule, but one of Tevildo's links above said that the 16" marks are in red to distinguish them. SpinningSpark 20:06, 5 October 2015 (UTC)
The 16" marks are likely intended for use with the nominal size of a standard 16" concrete masonry unit [3]. SemanticMantis (talk) 19:04, 5 October 2015 (UTC)
I would've said they were likely intended for use with the standard spacing of wall studs. But of course what's likely (and for that matter what's standard) will depend on one's location. -- (=talk) 04:45, 6 October 2015 (UTC)
Does the steel rule or its container display anything informational of a verbal or pictorial nature? Bus stop (talk) 13:08, 6 October 2015 (UTC)
See Tape_measure#United_States, although I dispute the placement of this information under "United States". Tape measures in the UK have these markings too. --Heron (talk) 18:09, 6 October 2015 (UTC)

October 6[edit]

Direct Connection[edit]

I have an old mobile with a LCD screen and a camera. I want to connect the screen to the camera directly without anything else interfering between. (talk) 08:53, 6 October 2015 (UTC)

Do you expect the screen to display a preview from the camera? If not, connect away! But, if you want the device to do something useful, you'll probably need some type of controller that can receive data from the camera, and convert it to preview images that can be sent to the display. You might also want the controller to configure the camera's exposure, at the very least. In other words, you probably need a piece of specialized hardware or software - an image processor - in between these devices. Nimur (talk) 10:13, 6 October 2015 (UTC)
At first I could not understand the question until I realised that the old mobile with LCD screen and the camera are two separate items. The problems will be: finding a cable that will interconnect the two devices, eg. a USB cable, and finding an app for the phone that performs the requested function for the specifc camera. I think you will find it impossible on both counts, especially if the devices are from different manufacturers. Akld guy (talk) 19:22, 6 October 2015 (UTC)
Bluetooth or wifi may be an alternative to the cable, leaving you with just the app problem. They are dependent on how far apart you want to site the devices and how good the path is at that distance. Akld guy (talk) 19:35, 6 October 2015 (UTC)
As previous replies indicate, unless both the phone (I'm assuming by "mobile" you mean "mobile phone") and the camera are designed to allow you to connect them together, you're going to have a difficult time. More likely than not you'll have to crack them both open and do a bunch of hardware modifications to allow the two devices to be connected together. And depending on what you want to accomplish you might have to hook them both up to an external computer to translate between them. This will require a good bit of electronics knowledge. If you just want to do it for fun/learning that's great, but if you're trying to accomplish some end goal there's probably a better way to do it. If you can describe what you're trying to accomplish we might be able to give suggestions. -- (talk) 23:01, 6 October 2015 (UTC)
Start reading something like this and see how long it takes you to get confused, and this is just the very basics. Vespine (talk) 00:35, 7 October 2015 (UTC)
If you have a non Nikon DSLR and the right Android smart phone, this may be of use [4]. However this isn't connecting the screen to the camera directly, but relying on the phone's hardware and software (as well as the camera's but I think you realised that). If you have a generic point and shot, I think you'll have far less luck since I'm not sure how many of those are designed to let anything else act as a screen. If you have a webcam, well again with the right Android phone (with USB OTG or host mode support) and the right software, you may be able to use the webcam although again you'll be relying on the phone's hardware and software. Webcams commonly aren't designed for direct connections to screens. If it's a security camera designed for direct connection to a monitor, perhaps with an analog connection, you'll need other stuff entirely. Nil Einne (talk) 02:27, 7 October 2015 (UTC)

While it's helpful to know the structure of an LCD display, you really don't need to know that because the aim is to connect the incoming data from the camera to the phone's LCD driver. The driver already exists in the phone. Your task is to connect the camera to the phone by USB cable (probably impossible if they are of different manufacture and definitely impossible if from the same manufacturer and with incompatible connectors), or by Bluetooth or wifi if the devices can both communicate via one of those means. So, assuming the camera and phone have compatible communication, the next task is to find an app for the phone that processes the camera's data and presents it to the phone's LCD driver. The appropriate app will be available if someone has already done it for that particular phone/camera combo; unlikely, when you consider that there are many, many models sold by each manufacturer; your chance of hitting on exactly the correct model combo is practically nil. If an app is not available, you could write your own, but that would involve research on the protocols used by both the phone and the camera. If the manufacturers do not publish the protocols, the project stops there. Assuming you had a copy of the protocols, it's a fairly trivial task to write the app, believe it or not. I'm guessing that writing an app is beyond the capability of the OP, since he/she wouldn't have asked the question if technically aware to that extent. Akld guy (talk) 20:11, 7 October 2015 (UTC)

Where did Lepidopterans evolve from?[edit]

Was it Trichoptera? Or did they evolve from Lepidoptera? Megaraptor12345 (talk) 14:41, 6 October 2015 (UTC)

Cladogram showing Lepidoptera and Trichoptera as sister clades.
At a glance, this cladogram from Lepidoptera#Evolution_and_systematics makes it look as though the Lepidoptera and Trichoptera formed from some unnamed clade in the early Triassic. If the graph is correct, then neither group evolved from the other. Rather, they both evolved from some other group. This stuff is difficult, and other current research findings may present slightly different cladograms. See also Evolution_of_butterflies. SemanticMantis (talk) 14:52, 6 October 2015 (UTC)
  • Ah, reading the linked article further Amphiesmenoptera is the name of the clade superorder that holds both Lepidoptera and Trichoptera, and the Necrotaulidae is the extinct group that both diverged from. No WP article on that, but this paper [5] discusses the fossil record and gives further refs. SemanticMantis (talk) 15:16, 6 October 2015 (UTC)
Thank you. But one last thing. Which extant group is the closest to this clade? Megaraptor12345 (talk) 16:58, 6 October 2015 (UTC)
Hmm, that might be above my pay grade :) To clarify, you are asking what extant group is closest to the extinct Necrotaulidae, right? It's a little unclear if anything in Amphiesmonepotera is any "closer" than anything else. But there are basal_(phylogenetics) clades within both Lepidoptera and Trichoptera. So for instance the Agathiphaga are some of the most primitive (i.e. least derived) of the Lepidoptera, but that doesn't help us compare their closeness to Necrotaulidae against say the Annulipalpia , which are I think basal among the Caddisflies. I can't find a good cladogram that includes all the groups of interest here, but I think it could even be the case that the living thing that is most like the Necrotaulidae could be among the scorpionflys. I poked around a bit on the Tree of Life web portal [6] for Endopterygota, but they don't have an entry for Necrotaulidae (I think their focus is on extant groups). The book: D. Grimaldi & M. S. Engel (2005). Evolution of the Insects. Cambridge University Press. ISBN 0-521-82149-5. is cited in a few of our articles that mention Necrotaulidae, so that would be another resource to check. User:Obsidian Soul may also have some helpful suggestions. SemanticMantis (talk) 18:37, 6 October 2015 (UTC)
  • Given that the cladogram SemanticMantis has provided is unrooted, all one can assume from it is that the Trichoptera are an outgroup to the Lepidoptera, not necessarily the sister group as such, even if that is most likely true. μηδείς (talk) 00:26, 7 October 2015 (UTC)
That's a good point about the cladogram; I was thinking of it as depicting an implied but unnamed root, but that's perhaps not the only viable reading. However Lepidoptera#Phylogeny specifically calls them sister groups, and this is also supported by Amphiesmenoptera and sister group.SemanticMantis (talk) 00:41, 7 October 2015 (UTC)
Yes, I agree they are in fact considered sister groups, and unless one wants to include as yet to be discovered even more primitive stem lepidopterans the issue is moot. The point is that that sort of diagram could also be written with horses, dogs and humans as members of a clade with birds as the outgroup, without implying that aves is the sister group of the Boreotheria. It's technical, but if the topic interests you you should be aware of the difference. μηδείς (talk) 03:35, 7 October 2015 (UTC)
This paper is the one PubMed hit for Necrotauliidae, with some beautiful photographs, and it happens to be published in one of the very few genuinely open access journals PLOS ONE, so I think there is going to be a nicely illustrated article turning up sometime. Wnt (talk) 11:11, 7 October 2015 (UTC)

which chemicals block serotonin production[edit]

only the production — Preceding unsigned comment added by Mahfuzur rahman shourov (talkcontribs) 14:48, 6 October 2015 (UTC)

Serotonin reuptake and breakdown inhibitors are common, in the form of SSRIs and MAOIs, these increase serotonin availability. I'm not aware of any drugs that block serotonin production. I'm not any kind of expert but as a reference it's notable that for the prognosis of serotonin syndrome is simply the discontinuation of serotonergic drugs, there does not appear to be a treatment to actively suppress the production of serotonin. Vespine (talk) 00:24, 7 October 2015 (UTC)
Fenclonine and p-ethynylphenylalanine, both do it by inhibiting tryptophan hydroxylase. Ssscienccce (talk) 03:08, 7 October 2015 (UTC)

@Ssscienccce, Medeis, and Vespine:OP requests everyone mentioned and everyone else to help in creating wikipedia articles for the inhibitor and the chemicals mentioned by the repliers as OP is using to access wikipedia and most sites are unavailable in the app, thus OP cannot create article by self

@Mahfuzur rahman shourov:: I just saw your post. It didn't send a message because their was no signature in it, {{reply to|Username}} only works when you have added '~~~~' to your post.
These are not medicines, Fenclonine has been tried as experimental treatment for carcinoid syndrome, but the side-effects were too severe to be useful. I assume p-ethynylphenylalanine is worse, has not been considered for humans it seems. They are used in research on lab animals, to study the role of serotonine in the brain. The fenclonine article exists and I don't see much more that can be added. About p-ethynylphenylalanine there is even less information, only a few abstracts of animal experiments. Too little to make more than a stub, in my opinion. Any reason why you want to make an article about specifically these substances? Ssscienccce (talk) 19:57, 7 October 2015 (UTC)

@Ssscienccce:OP inclusionist, expansionist, immediatist.Mahfuzur rahman shourov (talk) 16:25, 8 October 2015 (UTC)

Gravity, dark matter and energy[edit]

1) When a supernova occurs What happens to gravity, since its an energy?

a) Does it move with the supernova? If so at what level does the gravity stay of a neutron star and a black hole?

b) Since Type la Supernova creates a 'shell-like' remanant, gravity should exist, in the shell like remanant? True/False?

2) If dark matter was created due to/during the matter combination process after the Big Bang, how did dark energy came into existance?

2.1) If dark energy was there from before we know it, and mixed itself, shouldn't gravity do the same? - 'Gravity' and 'dark energy', weren't they suppose to work like the 'force' motion; pull and push...?

Space Ghost (talk) 20:16, 6 October 2015 (UTC)

Firstly, gravity is a force which is NOT the same thing as energy. Gravity can be viewed as a property of mass/energy.
1) I'm not sure what you mean by "what happens to gravity"? A supernova isn't a "thing", it's an event, it's something that happens TO a star.
a)Again sorry but I can't quite work out what you mean by "If so at what level does the gravity stay of a neutron star and a black hole?" Neutron stars and black holes are what's left behind after a supernova, they are typically very massive and therefore have large gravity. :b) Gravity exists everywhere mass exists.
2)We have articles on dark matter and dark energy, quite a lot is still not known about both of them.
2.1)What do you mean by dark energy "mixed itself"? We really don't know much about abut dark energy apart from that we're pretty sure it exists. I'm not sure you can really draw any strong comparisons with gravity, or anything really. Vespine (talk) 21:41, 6 October 2015 (UTC)

1b) read Shell theorem which talks about the gravity of a spherical shell. Graeme Bartlett (talk) 22:40, 6 October 2015 (UTC)

Okay! -- Space Ghost (talk) 19:13, 7 October 2015 (UTC)

Vespine: About dark matter and energy: I'm confused with the thought i.e. if scientist can think that dark matter formed after the primodial atom explosion, why did they not think the same about dark energy?

About gravity: I've read in one of our article(s) which I can't recall now that, scientists are capable/could be capable of creating laser communicative methods which won't get distorted in space. Therefore I'm wondering, can the force 'gravity' and 'dark energy' get distorted by a supernova event?

Space Ghost (talk) 19:13, 7 October 2015 (UTC)

I'm just an enthusiast so really not familiar once you start getting into minute details. "if scientist can think that dark matter formed after the primodial atom explosion" Again, dark matter and dark energy are INFERRED, we've never really detected either directly, i don't believe we know how or when either formed. Anything you hear about specifics is just hypothesis at this stage, apart from the EFFECT they have on visible matter.
"scientists are capable/could be capable of creating laser communicative methods which won't get distorted in space." That sounds implausible to me. Regardless, I really don't know what you mean by a supernova distorting the force of gravity. A star has mass, an exploding star still has mass, that mass has a property called gravity, what do you mean is it "distorted" do you mean like light is distorted by gravity, is gravity distorted by a supernova? I don't think so, I think it would be like saying does the rock you throw in the pond distort the ripples it creates in the water? well, the ripples ARE the distortion in the first place. Vespine (talk) 21:37, 7 October 2015 (UTC)
Your statement/example gives me the understanding of dark energy as being present from before the primodial atom explosion. I just can't put my finger on the 'gravity' yet.
Ignore everything else you did not understand, let me learn a bit more. And sorry if I come across as a speculator or someone who's busy with the minute details. Thanks and take care Face-smile.svg -- Space Ghost (talk) 18:29, 8 October 2015 (UTC)

It's sort of unfortunate that "dark matter" and "dark energy" have such similar names. They have not much more in common than the word "dark". Well, that plus the fact that we don't know what they are and infer their existence from astronomical observation. But that's really where it ends.
The effects of dark matter are observable at close range, at the scale of our own galaxy. It's really really clear that there's something there. We don't know exactly what it is, but we can clearly map the distribution of mass-energy that has to be there to explain the orbits of stars. There are no reasonable alternative explanations. Moreover, it's not that difficult to understand why we don't observe it directly, because if the leading explanation (weakly interacting massive particles or WIMPs) is correct, well, we really wouldn't. And that explanation fits well with existing particle physics.
Dark energy is much more tentative and speculative. If it exists (no one would say "if it exists" about dark matter), the effects of dark energy are inferred from observations at a much larger scale, a cosmological rather than merely galactic scale. There is no good candidate for what it would be in terms of existing particle physics if I'm wrong about that, I'm sure someone will correct me. And its interpretation as "energy" in the first place is perhaps somewhat arguable; it could be taken instead as just a term in the field equations for spacetime, with no specific material interpretation. --Trovatore (talk) 19:29, 8 October 2015 (UTC)

October 7[edit]

Does SETI target stars that could detect us?[edit]

It occurs to me that astronomers are really excited about hunting exoplanets using the transit method because they stand a chance of detecting atmospheric content. That means that the plane of the exo-planet's ecliptic more or less intersects the Earth.

It follows that aliens who wanted to find other civilizations to talk to would find our planet by the transit method too...which suggests that SETI should preferentially search for radio signals along the plane of the ecliptic.

Do they actually do that - or do they avoid the ecliptic for some reason? SteveBaker (talk) 05:02, 7 October 2015 (UTC)

The idea has been discussed: Don't think Seti@home is doing it specifically, they get the data but don't have control of the telescope; if a signal is found they ask for observation time. Data comes from Arecibo Observatory, which has a 40° cone of visibility around zenith. It's located at 18°22'N so I assume they can observe just above half the region in question? Ssscienccce (talk) 07:50, 7 October 2015 (UTC)
SETI optimism is stimulated mainly by the Drake equation which suggests a finite probability that extraterrestrial civilizations have developed communications which we might detect (without quantifying the probability) but does not give any reason to prefer ecliptic planes.
A planet's ecliptic is an inopportune plane in which to transmit to a very remote destination because of the difficulty for a receiver to distinguish the transmission from the background noise of the star, the star blocks the signal path for part of the planet's year and the signal frequency suffers maximum Doppler shifts. The few tentative (reckless?) SETI transmissions (Active SETI) have all been away from the ecliptic e.g. towards Messier 13 at declination +36° in 1974; a morse message from 1962 has long passed Venus and has surely dissipated on its way towards Gliese 581 declination −08°. As if to emphasize distaste for the ecliptic, NASA has transmitted music by The Beatles to Polaris declination 89° with no reply expected ever. So there is little enthusiasm for focussing the limited SETI radio listening resources on ecliptic directions. However Geoffrey Marcy, an extrasolar planet hunter, examines optical spectra taken during extrasolar planet hunts for a continuous, rather than pulsed, laser signal that has been suggested as a way for alien civilisations to communicate. Bestfaith (talk) 10:30, 7 October 2015 (UTC)
@Bestfaith: Wait... is the background noise for us listening actually worse for stars in our ecliptic than from other locations, provided you're not pointing at Jupiter or something? What does it come from? And our transmission to Polaris would be perfectly OK with the OP's idea -- if it had a transiting exoplanet. And surely there must be a way to compensate for Doppler shifts over the course of a year (and the day) ... if we had an alien signal to listen to for that long! Wnt (talk) 10:55, 7 October 2015 (UTC)
The OP's question is about extrasolar planets that we discover because Earth is in their ecliptic plane; they need not lie in Earth's ecliptic plane. The worst place to detect a weak radio emission is in the same direction as a star, which is generally a powerful wideband emitter. One of the pioneers of Radio astronomy J.S. Hey, a British Army research officer, made the first detection of radio waves emitted by the Sun in 1942. If one could choose a source location, it would be somewhere in "black space" with only the CBR plus our own QRN and QRM for competition. Sources in Earth's own ecliptic might occasionally be received well, the occasions being particular dates in the year when reception is not blocked by Jupiter or a wide array of things such as the Sun, other planets, dwarf planets, asteroids, Kuiper belt and tens of thousands of other space junk that infest the Solar System ecliptic. Doppler shift can indeed be compensated in an active receiver if you have exact ephemeris data on the moving source and if the inconvenient aliens don't confuse the issue by Frequency modulation. I don't see the OP or anyone being serious about NASA contributing to a Beatlemania in year 2442 some 434 light-years away at Polaris which is a 3-star system, but anyone can speculate how well a popular 4-star group will be received there by and by. Bestfaith (talk) 16:48, 7 October 2015 (UTC)
The Op says that if extraterrestrials would send signals (using their own "Arecibo" antenna), they would aim at planets they can see. So the signals will most likely come from planets that can detect us, not planets that we can detect. If they use the same methods, they would detect us when they are in our ecliptic plane. Ssscienccce (talk) 18:54, 7 October 2015 (UTC)
The notion that unearthly beings watch and care what happens here on Earth had more credence when Ptolemy's Geocentric model was in style. Notwithstanding Copernican heliocentrism the OP's prophetic insight into the intentions towards us of said extraterrestrials surely calls more for a Leap of faith than of logic. If we want (and dare) to send a message in our ecliptic plane we may do better optically using a huge dirigible sunshade for semaphore than at radio frequency. Bestfaith (talk) 01:40, 8 October 2015 (UTC)
Aliens with technology more advanced than ours, if they wanted to look for planets around other stars, would probably use space telescopes. There is no serious barrier to building reflecting telescopes a thousand kilometers across, if they are built in space away from planets. That's far larger than needed to directly resolve planets orbiting nearby stars. Any advanced civilization would surely do this as a self-defense measure: they'd want to know who is nearby. Looie496 (talk) 15:14, 7 October 2015 (UTC)
@Looie496: Well, one of the more cogent explanations given for the lack of alien communications is that once a planet starts chirping, berserkers swoop down on it and do something to remedy the problem. In that case, communications might be received only from low-tech planets with limitations much like ours. Wnt (talk) 15:58, 7 October 2015 (UTC)
Yes, there's a whole range of speculative resolutions to the Fermi paradox, this one fits under Fermi_paradox#It_is_the_nature_of_intelligent_life_to_destroy_others. SemanticMantis (talk) 17:07, 7 October 2015 (UTC)
I'm not trying to address the Fermi paradox, I'm just saying that the transit method is only likely to be high end technology for a few decades. Once a civilization has the ability to use the transit method, it probably won't take more than a few decades before it can build 100 meter reflecting telescopes in space. That's sufficient to directly resolve Earth-size planets around at least a few dozen of the nearest stars. (I personally think the solution to the Fermi paradox is that advanced civilizations don't actually want to advertise their presence. We aren't trying to do it, are we?) Looie496 (talk) 17:37, 7 October 2015 (UTC)
Sure, I think that's a fair point, I was just providing a link to our WP coverage of the idea Wnt was getting at. Then again maybe It_is_the_nature_of_intelligent_life_to_destroy_itself and those few decades between transit methods and large space telescopes turn out to be very perilous. As for your question: yes, we have tried a few times to advertise our presence, but perhaps ineffectually. See Arecibo_message which was more of a proof-of-concept than a serious attempt. Other things mentioned at Active SETI. Last Feb. there was a conference session of the annual meeting of the AAAS dedicated to discussing whether we should be attempting this sort of thing, and if so, how to do it properly, etc., so intentional "advertising" of human life on Earth isn't quite off the table [7]. I don't think there's any formal published proceedings of that conference, but a little more info on what was said here [8]. SemanticMantis (talk) 17:58, 7 October 2015 (UTC)
This video from PBS's Space Time channel takes a look at how you might go about effectively signalling other intelligent life. -- (talk) 07:02, 8 October 2015 (UTC)
In regards to the Fermi paradox, my guess is that we may simply be the first civilization in our galaxy. Sexually-reproducing multicellular organisms took almost 4 billion years to arise on our planet; that's almost a third of the age of the universe. Also, our sun is a metal-rich yellow star outnumbered hugely by metal-poor red dwarfs. For two great explanations as to why civilizations don't get off-planet, read Frederic Brown's seminal short-story, The Waveries (available on line), and Greg Bear's more metaphysically speculative Blood Music in the extended novel-length version. μηδείς (talk) 17:30, 8 October 2015 (UTC)

Exploration of the Earth's core[edit]

I was just reading some information that Mantle plumes are in fact real, large, and go all the way down to the outer core boundary. They apparently come all the way up to the upper mantle, if not to the volcanoes on hotspots themselves, though they get wiggly above 1000 km. This means that, for the first time, there seems to be persuasive evidence that (with better mapping) a voyage of exploration can be planned clear to the iron core of the Earth. So I should ask...

1) Do we have anything like a 4000-C-able probe? Something that is completely solid, that has relatively constant expansion/contraction coefficients for both temperature and pressure throughout, and can travel without moving parts using magnetohydrodynamic propulsion or something?

2) Do we have a means for it to send back data? I'm thinking there was a recent neutrino transmission/reception experiment, but that required a very big transmitter indeed. Seismic transmission is possible ... but that's low bandwidth. Or it could come back... but that's dicey. Anyone had a better idea?

3) Is it possible for a probe to extract practical amounts of energy from the surrounding rock and temperature/current differentials? Would a small nuclear reactor supply enough power for it to move?

I'm feeling now there must be a way. Wnt (talk) 14:27, 7 October 2015 (UTC)

This reminds me of some articles published back in the 1970's about exploring the mantle. The wonder of the WWW has saved me the effort of climbing up into the attic to dig them out. Radioactive Sinkers – New Scientist Magazine.--Aspro (talk) 15:29, 7 October 2015 (UTC)
I think a more realistic approach might be to drop some solid (tungsten ?) spheres in a location that will draw them down deep into the Earth, then reflect signals off them from the surface (or a mine). This will give us info about the flow patterns. StuRat (talk) 15:46, 7 October 2015 (UTC)
You seem to be imagining mantle plumes as liquid corridors. That's not true. With the exception of places very near the surface with limited local melting, the entire mantle is a solid, or more properly a rheid. Rheids are solids that deform and flow under pressure. You should imagine something like cheese that is a solid but can be permanently deformed by pushing on it. Mantle plumes are solid flows that move at minuscule rates (e.g. 30 cm / yr). If you wanted to move through one you'd have to either drill or melt the rock on the way through it. Dragons flight (talk) 15:52, 7 October 2015 (UTC)
@Dragons flight: Very good point. But can you give a better sense of their viscosity? I mean, I bet you could design a nuclear submersible capable of "swimming" through cheese by some means or other. But according to rheid, granite at STP is also within the definition, and I don't think it will go through that.
Also, the article currently says nothing about rheids/solids/liquids/viscosity/etc., so if you can update it that would be much appreciated! Wnt (talk) 16:05, 7 October 2015 (UTC)
1021 Pa-s, give or take an order of magnitude or so. Granite is the right analogy to have in mind. Dragons flight (talk) 16:40, 7 October 2015 (UTC)
That's actually more viscous than granite! I've read of the mantle being "semi-solid", and this is the part of it that is flowing ... never imagined it would be that tough to pass through. Wnt (talk) 18:51, 7 October 2015 (UTC)
Here's a ref that backs up the viscosity given above [9]. Here's one that focuses on the ratio of viscosities between the ambient and buoyant fluid [10]. Seems that sometimes one bit can be several hundred times less viscous than nearby bits. SemanticMantis (talk) 19:00, 7 October 2015 (UTC)
The mantle flows not because it is "soft", but rather because the deforming pressures are enormous. Dragons flight (talk) 20:02, 7 October 2015 (UTC)
The answers to 1, and 3 will be "no". For 2, you could probably send data back via seismic waves, perhaps using a magnetorestrictive material with a pulse of current to vibrate. Neutrinos would require too much equipment to make into a controllable beam. (I suspect I have a spelling error in there) But if the probe can go down, perhaps it can come back up with all the data on board. Graeme Bartlett (talk) 21:32, 7 October 2015 (UTC)
See:Magnetostriction to understand magnetorestrictive. Yet, the amplitude of such a device will be very small and of high frequency, which don’t carry very well over long distances. However, such a probe will only descend slowly, so a piston type seismic transducer (which produces lower frequencies) should have plenty of time to send the telemetry data up very slowly, (providing such a probe could be built),(this is to do with signal to noise ratio and bandwidth, which is why the Voyager space craft can still remain in contact with Earth by sending its signals very, very slowly). The Chines who invented the rock may have never imagined that one day they will go to the Moon, Mars and beyond. --Aspro (talk) 12:47, 8 October 2015 (UTC)

are sexual disorders caused by Fluoxetine usage temporary or permanent[edit]

OP wants exhaustive replies with references — Preceding unsigned comment added by Mahfuzur rahman shourov (talkcontribs) 15:38, 7 October 2015 (UTC)

Read Fluoxetine#Sexual dysfunction then follow the references and read those. Ariel. (talk) 16:34, 7 October 2015 (UTC)

more needed, updated ones — Preceding unsigned comment added by Mahfuzur rahman shourov (talkcontribs) 16:45, 7 October 2015 (UTC)

Don't know if you saw the old article about Post-SSRI sexual dysfunction here. See the AfD here for why it was deleted. Seems it didn't have reliable sources. What is known for sure is that SSRI's often cause temporary dysfunction during treatment, prevalence and duration of post-SSRI dysfunction is unknown so far I think. And one more paper. Also found on PUBMed. But primary source. So these probably aren't WP:MEDRS, it seems few researchers or doctors want to do such studies it seems. Ssscienccce (talk) 17:36, 7 October 2015 (UTC)

If humans had remained isolated from each other for longer time, will they evolve into different species?[edit]

What if different populations of Homo sapiens never join together? What if one population undergoes a genetic bottleneck or founder effect so it develops different characteristics from another population? A wolf and coyote can mate to form the coywolf. If two humanoid species mate, are they both human or is the offspring a hybrid? (talk) 20:25, 7 October 2015 (UTC)

According to Hybrid (biology): "Modern humans acquired new traits and evolved to the present, very fertile form of the species via hybridization with at least two other hominid species: Neanderthals and Denisovans." Things might not work out if we were further apart than we were, obviously. However, you need a very long time for that. If it happened again, we would have to ask ourselves whether the offspring is human or not. --Scicurious (talk) 21:36, 7 October 2015 (UTC)
To your title question, the answer is "maybe, it depends on how long they are isolated, and how you are defining species." See species problem, species complex, speciation, and allopatric speciation. SemanticMantis (talk) 21:37, 7 October 2015 (UTC)
Timeline of human evolution, Fully (anatomically and behaviorally) modern humans is 200,000 years old. If a generation is roughly 25 years , we're talking about 8000 generations back we're still modern humans. You need to go back millions of years before we stop being "human". Vespine (talk) 21:52, 7 October 2015 (UTC)
Anatomically, pretty much. We've been a little taller and shorter, generally. Behaviorally, those old folks didn't even spend their day farming, let alone pretending to run a virtual farm from their phone. Many "new" languages now, too, including all of them. I'm pretty sure those damn, dirty apes twerked, though, InedibleHulk (talk) 08:24, October 8, 2015 (UTC)
The answer is yes, eventually, but it would take many thousands of years, perhaps hundreds of thousands. Species are defined as groups different enough to be unable to interbreed and produce fertile offspring. That would be bound to happen eventually, but it wouldn't be likely to happen quickly. Looie496 (talk) 21:56, 7 October 2015 (UTC)
No, that's not the definition of species. Or at least not one that is used outside of high school biology classes. Ring species are very common. E.g. many Larus spp. can interbreed and produce fertile offspring, as can many Anas species. For example the blue-winged teal, the cinnamon teal and the green-winged teal are different species by almost any reckoning. They look different, they act different, and yet they can interbreed to produce fertile offspring. They have overlapping ranges, and tend not to interbreed much in the wild, but they can and do. Anas#Systematics specifically mentions how fertile hybrids confound the systematics of that group. The truth of the matter is, there isn't any universally accepted definition of species; the term is simply operationalized as appropriate within different texts and research programs. SemanticMantis (talk) 22:22, 7 October 2015 (UTC)
The best example of this I know are the "Pygmies" of Africa, such as the Twa. While AFAIR some of these groups are genetically close to other Africans, some are notably diverged; it brings sympatric speciation to mind. I find myself fond of the notion that these peoples are preadapted to space travel, though alas we do not have the literal data for how well they stand up to space, having (at least) good intellect for small mass. They also have a huge reservoir of diversity, permitting them to adapt to new environments. As such, I have considered them as the base of a new species, "Homo apotelesmatis", which is - if any is - destined to dominate in an "Out of Earth" scenario. Wnt (talk) 00:54, 8 October 2015 (UTC)
I think (no refs) that developments in biotech (which happen on a distinctly non-evolutionary timescale) may bring about a system in which a small minority who've enhanced and augmented themselves like you've never seen, lords it (more than they do already) over a downtrodden majority, who can't do anything about it (i.e. like pre-1917 conditions, only perpetual) purely because they lack IQ/longevity/concentration/strength/cohesion and whatever else could be an object of artificial enhancement. This is a scenario humanity is exceptionally ill-equipped for, morally. Asmrulz (talk) 02:38, 8 October 2015 (UTC)
That'd be this book, unless this one happens instead. Ian.thomson (talk) 08:07, 8 October 2015 (UTC)
The main hope against that scenario is that the people who play god may not stack up against natural selection. They can try to enforce all sorts of desirable characteristics, but in the end their meddling, their striking out of undesirable characteristics and with it the loss of genetic diversity, dooms their perfect humans to helpless mediocrity. Also, my take on history is that the races enslaved are generally superior to the slavers (for example, Africans brought in to work plantations that whites couldn't) and so the situation is inherently unstable.Wnt (talk) 15:36, 8 October 2015 (UTC)
There is a bit of a controversy over whether Neanderthal Man was a separate species (its taxonomic name Homo neanderthalensis implies that strongly) or a subspecies of Homo sapiens.
The two species had a common ancestor. Quoting from our article on Neanderthal man:
"From mtDNA analysis estimates, the two species shared a common ancestor about 500,000 years ago. An article appearing in the journal Nature has calculated the species diverged about 516,000 years ago, whereas fossil records show a time of about 400,000 years ago. A 2007 study pushes the point of divergence back to around 800,000 years ago."
So, at some point, physical isolation (along with mutations) may account for there having been two races of man sufficiently different that their DNA genomes are only 99.5-99.9 percent identical - modern man and Neanderthal man. All humans carry some common genetic material with Neanderthal man, non-Africans more so than Africans. loupgarous (talk) 07:35, 8 October 2015 (UTC)

Removing ammonium nitrate stain from phone[edit]

Today I got hit in the face with a basketball in gym class. My coach went to get me an instant cold pack. When he returned, he said he had accidentally busted it, but that it would probably be okay because it was just water(he didn't read the label, obviously). It was Equate brand, and they use ammonium nitrate in their ice packs. I wrapped it in a paper towel and put the non-leaking part on my face, but accidently squeezed too hard. Some whitish substance dripped down my arm and onto my pants pocket, which held my phone. I washed my hands, but only discovered the white stain on the back of my phone when I got home. How do I remove it from my phone and jeans?2602:306:CC43:A8A0:C8A1:D21E:F7DC:74C1 (talk) 23:53, 7 October 2015 (UTC)

Ammonium nitrate is water soluable, so removing any residue would just require a rinse. However, I would assume you already tried this, so must conclude that it has oxidized (bleached) the jeans and phone material (plastic ?). I see no way to un-oxidize it, so you may be out of luck. You may need to live with it or replace it. (For bleached jeans, one option is to replace the missing pigment using a marker, but it has to be laundry marker or it washes out, and it never looks quite right in any case.) StuRat (talk) 00:57, 8 October 2015 (UTC)

October 8[edit]

A Fourth Dimension[edit]

In my geometry class, we watched this video about dimensions. It had this city of two-dimensional shapes that weren't aware of a third dimension (can't remember the name of this particular film). It just got me wondering if there was a fourth dimension, and if our minds would be able to comprehend it. What could the fourth dimension be? The mind? Space? Something with the senses? Can we even begin to imagine what it could be? How could we discover it? Thanks.2602:306:CC43:A8A0:C8A1:D21E:F7DC:74C1 (talk) 00:12, 8 October 2015 (UTC)

There is a fourth dimension, time. Whenever you specify the location of an object, you need to include the 3 spacial dimensions but also the time, as the object won't be there permanently (although some things seems permanent, on a human timescale, so the time dimension is often omitted for things like mountains). StuRat (talk) 00:27, 8 October 2015 (UTC)
As far as I know, the problem with extra spatial dimensions is that they might be expected to consume particles, forces, and so forth. A radioactive atom breaks - the pieces go left and right, up and down, back and forth, why not zerk and krez? But we see every particle come out, in normal 3D space, by seemingly normal laws of Euclidean physics. In M-theory there is this idea that there are extra dimensions but they are "curled up", so you go the tiniest smidgeon of a nothing in them and you're back to where you started. Sort of like beads on a string - they seem confined to a one-dimensional space but if you look really close you can see they are able to rattle back and forth a bit too, rotate etc. But honestly I still don't really understand that, because wouldn't a particle looping around and round in a fourth dimension have energy diverted to its motion in that space that leaves it going too slow in regular space? But since M-theory ties these states to various physical forces, I am probably missing the point. Wnt (talk) 00:47, 8 October 2015 (UTC)
In at least some of these models, possibly all, particles are spread evenly across the extra dimensions in a low-frequency (so also low-energy) mode, analogous to a transverse mode of a waveguide. To get something resembling motion in the extra dimension, you'd need to excite higher-frequency modes, but their energy is high enough that they haven't been seen in experiments.
Another type of extra-dimensional model has the particles (except the graviton) confined to a 3+1 dimensional surface in the higher-dimensional space. Apparently this sort of thing shows up naturally in string theory. -- BenRG (talk) 04:04, 8 October 2015 (UTC)
The OP may have seen the 2007 movie based on Flatland: A Romance of Many Dimensions an 1884 satirical novella by the English schoolmaster Edwin Abbott Abbott. Bestfaith (talk) 01:08, 8 October 2015 (UTC)
Zerk and krez? I am not even going to ask permission to steal that. What a great thread. I read Flatland back in the 80's when there was no non-public domain version of it. Great thread. Am off to look zerk and krezward for the 2007 film. μηδείς (talk) 01:25, 8 October 2015 (UTC)
  • ana and kata are sometimes used for the extra pair of directions. —Tamfang (talk) 09:52, 8 October 2015 (UTC)

As far as I can tell, all of you live in two dimensions. --Amble (talk) 02:18, 8 October 2015 (UTC)

Oh come on people. We're talking about geometry here, we DO have quite well defined Four-dimensional space in geometry. Also Tesseract is relevant here. Vespine (talk) 03:05, 8 October 2015 (UTC)
It's not clear that the OP is really talking about geometry. He/she asked what was "the" fourth dimension. Many many people seem to think that's somehow a meaningful question. I would ask those people, what is "the" first dimension? Is it left/right? Is it north/south? Or maybe galactic north and galactic south? Up/down? Forwards/backwards? In any of those cases, what makes that the first one?
If you can't figure out what the first one is, how are you going to figure out the fourth one?
Ancient Greek geometry was all coordinate-independent. Then analytic geometry got people thinking in terms of Cartesian coordinates, and the coordinate-independent view had to be rediscovered and made precise and rigorous at some point in the history of differential geometry. I wish we had an article on that but I am not able to find it. General covariance touches on it but is not quite what I'm talking about. --Trovatore (talk) 03:34, 8 October 2015 (UTC)
Trovatore is exactly correct.
Furthermore, in mathematics, the term "dimension" has a specific meaning. Often, when real scientists and physicists talk about multiple dimensions, they are not talking about spatial coordinates. This terminology frequently confuses readers of popular-science who have not formally studied mathematics and physics. For example, we have an article on parameter spaces and configuration spaces. Scientists may use the term "dimension" to represent one coordinate in these abstract or generalized models.
Nimur (talk) 04:10, 8 October 2015 (UTC)
  • StuRat mentioned spacetime and Vespine mentioned Euclidean four-space, but please note that these are not the same thing. Spacetime has a Minkowski geometry in which time has to be distinguished from the spatial dimensions. Special relativity can be expressed as rotations between time and space, but they're not quite the rotations with which you're familiar. —Tamfang (talk) 09:52, 8 October 2015 (UTC)
    Well, sort of. There are "timelike" and "spacelike" directions, and those can be distinguished in a coordinate-free way. However, there is no distinguished "pure time" dimension. --Trovatore (talk) 18:25, 8 October 2015 (UTC)

why is the Lasioderma serricorne called tobacco beetle, if he is eating everything?[edit]

I have read the article in german and I have 2 questions: The first is above and the second is:

  • is he able to eat the pure tobacco plant (like snails) or does him harm this scent of a blossoming tobacco plant? (such as mosquitoes or bees, for example).

Reading the german and the english article does make me feel, like he is only eating tobacco products, not the pure plant himself when it is growing. Am I right? Because this would make my question even harder, why a beetle what isn´t living with the tobacco plant has got this name.. here is a 1:1 translate of the german part with google translate what this beetle is able to eat (I have not corrected it, just if someone wants to grew the article about Lasioderma serricorne) numerous foods, such as flour, dried fruits, such as dates and raisins, cereals, cocoa, coffee beans, spices and herbs, nuts, rice, animal-dried foods and other foods that chambers extended period in storage cabinets, and stored like. In addition, you will find the beetles also dried plants, as in herbaria, decorations and potpourris, in medicines, in insect preparations, in filling of furniture, paper mache and the binding glue of books. Thank you and greetings!--Hijodetenerife (talk) 05:48, 8 October 2015 (UTC)

Like any animal, tobacco beetles do all sorts of stuff. But they're notorious for one thing. It's like why we don't call him "Zorba the House Builder". InedibleHulk (talk) 06:05, October 8, 2015 (UTC)
The black carpet beetle is reddish brown and can live outdoors just fine. InedibleHulk (talk) 06:26, October 8, 2015 (UTC)
Same as this guy. (talk) 11:57, 8 October 2015 (UTC)

any other answers?--Hijodetenerife (talk) 22:27, 8 October 2015 (UTC)

The tobacco beetle is so named because of the tremendous economic damage he incurs upon tobacco farmers. The beetle will eat either the leaves off the live plant, or the aging tobacco being stored in a warehouse. Tobacco beetles will also eat virtually any dried vegetable matter. I have not been able to find out who so named the beetle or when. I suspect that history is buried in an 18th century Latin or German manuscript. If you do manage to find some of the sources cited in the history section of this paper, maybe you could find out. Someguy1221 (talk) 23:46, 8 October 2015 (UTC)

list of chemicals in blood that increase when a person goes into physical exertion mode[edit]

running, weight lifting, swimming etc compared to rest state. — Preceding unsigned comment added by Mahfuzur rahman shourov (talkcontribs) 15:52, 8 October 2015 (UTC)

The concentration of blood lactate is usually 1–2 mmol/L at rest, but can rise to over 20 mmol/L during intense exertion. Immune cell functions are impaired following acute sessions of prolonged, high-intensity exercise, and some studies have found that athletes are at a higher risk for infections. Athletes may have slightly elevated Natural killer cell count and cytolytic action, but these are unlikely to be clinically significant Bestfaith (talk) 18:04, 8 October 2015 (UTC)
Epinephrine#Measurement_in_biological_fluids - its concentration in blood can increase 10x during exercise. SemanticMantis (talk) 18:33, 8 October 2015 (UTC)

@Bestfaith and SemanticMantis:creatinine, cortisol, testosterone, do they increase? what other chemicals increase?Mahfuzur rahman shourov (talk) 04:58, 9 October 2015 (UTC)

October 9[edit]

When will the Himalayas stop rising[edit]

Does anyone know when the Himalayas will stop rising? — Preceding unsigned comment added by (talk) 00:13, 9 October 2015 (UTC)

According to Himalayas#Geology, the plate tectonics driving this rise are expected to continue for another 10 million years. However, the current rate at which the Himalayas are rising, 5mm per year, is unsustainable over that time period (it leads to an absurd prediction that the Himalayas will eventually rise to 37 miles in height, which is thicker than the plates themselves). So we have predictions for how long the subduction of the Indian subcontinent will continue, but I haven't seen predictions on when the mountains themselves will stop getting higher, or if they'll collapse under their own weight. Someguy1221 (talk) 00:36, 9 October 2015 (UTC)
They're constantly being eroded by wind, flowing water and ice – the bottom of the mountain rises by 5 mm, but the top is reduced slightly (on average 2 to 3 mm a year), so the actual growth is slower. Smurrayinchester 09:01, 9 October 2015 (UTC)

If first frost is November or October then when does plant volume peak?[edit]

As in cubic meters of organisms per acre.

Google says deciduous trees only grow a few months a year, so they must peak for an extended period until they start losing leaves. Species like maples might slowly decline for months as they seem to start losing seeds early. Do some weeds that are annuals grow until frost kills them, even if it's once in 30 years late? Or is a period of no growth (besides seeds) a normal part of annual weeds' lives? Are there any rules of thumb like grasses growing the latest or trees stopping growth earlier than bushes? Are there any common humid continental annuals in nature that shrink (besides seed or fruit loss) before frost hurts them? (possibly to cannibalize less vital anatomy for resources to make seeds?) Sagittarian Milky Way (talk) 09:24, 9 October 2015 (UTC)

what factors (deficiencies, surpluses, exposures etc) cause increased rate of cell death and decreased rate of regeneration, leading to incidents such as more-often spontaneous bleeding, bruising, scarring etc[edit]

OP got curious after watching some patients of wasting disease — Preceding unsigned comment added by Mahfuzur rahman shourov (talkcontribs) 11:05, 9 October 2015 (UTC)