Wikipedia:Reference desk/Archives/Science/2009 March 17

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March 17

Trachelospermum jasminoides

what would happen if u consumed the leaves,flower...ect. of this plant? would the effects of ibogain be felt? or is the plant poisones? —Preceding unsigned comment added by 76.14.124.175 (talk) 00:48, 17 March 2009 (UTC)

According to this reference, "the whole plant is poisonous." - Eron^Talk 00:59, 17 March 2009 (UTC)

piperazine

beacause Piperidine and piperazine are very similar, do they have the same effects on the brain? —Preceding unsigned comment added by 76.14.124.175 (talk) 01:00, 17 March 2009 (UTC)

I'm not aware of human therapeutic uses of piperidine or piperazine. Both of those articles do list derivatives, among them antipsychotics. --Scray (talk) 02:10, 17 March 2009 (UTC)

(post e.c.) Neither article mentions psychotropic functions for either Piperidine or Piperazine, although some of their derivatives are psychoactive as Scray mentioned above. I'm not sure about the metabolites. Although they have similar functional groups and are fairly close in shape and size, that does not always translate to similar behavior biologically. Docking (molecular) describes the basic idea: small differences in shape can have major effects on the ability of a compound to bind to an enzyme's active site (or other relevant portion). Sifaka ^talk 02:33, 17 March 2009 (UTC)

Both piperidine and piperazine block nicotinic cholinergic receptors. Piperidine is more potent than piperazine. [By the way, piperazine is used to treat parasitic infections in people.] Axl ¤ [Talk] 10:47, 17 March 2009 (UTC)

Yeah, because it's substantially more toxic. To humans too. The reason why these are on drug schedules isn't because they're psychoactive or remotely close to it. It's because they're very common precursors in organic chemistry. Which would include drug synthesis. --Pykk (talk) 19:46, 17 March 2009 (UTC)

Theory of Chemical Emotions: Pointless to Pursue Happiness?

Since most of our emotions are chemical reactions in the brain, and while the events of our lives do trigger the release of those chemicals, they do not increase or decrease production (apparent from exercise, stress, eating habits, and drugs). So two genetically identical twins with similar exercise, stress, and eating habits should experience the same total amount of happiness, right? Regardless of what is happening to them? (assuming they can keep themselves from getting stressed out about the events). One of the twins might have events that trigger lots of happiness in short bursts while the other has a more constant rate of happiness, but they should both experience the same total amount.

If this is true, doesn't this completely undermine the point of perusing things that make us happy if we will inevitably experience the same amount of happiness regardless? Thus we should foremost pursue good eating habits, exercise habits and controlling our stress levels and not worry about anything else (especially since worrying lowers our Serotonin production)? Also if this were true it would redefine what services we need to provide to 3rd world countries as charity as they will find their own happiness in their poverty as long as they can be well fed and control their stress levels, correct?

Something seems really wrong about this theory but I'm not sure where the hole is. It does readily explain why people who have everything find sadness in small details (like being spoiled) and people who have nothing still find happiness in the small details, though to say that we each have an amount of happiness specifically determined by genetics, stress, eating, and drugs seems a little much. What am I missing? Thanks. Anythingapplied (talk) 01:53, 17 March 2009 (UTC)

I don't see how any of this changes the way we should treat the less fortunate (including what we call the third world). Actually the whole thing about people having "nothing" being just as happy as others is bunk. In case you've never tried it being poor is really stressful. Wealth makes people happier until they reach some place around middle to upper middle class, additional wealth after that point doesn't do anything for happiness. Since what it means to be middle class changes over time I imagine this response ties to our evolved sense of justice which is tied into the chemical system you mentioned. Anyways I'm not going to offer a well wrapped answer but I will say that Walt Disney said something to the effect that "for every smile there must be a tear" and XKCD make a good point about arboreal rodents.--OMCV (talk) 02:17, 17 March 2009 (UTC)

I'm not at all familiar with this particular topic but I have a feeling that part of the problem may lie in your premise: happiness is not the same as the level of neurotransmitters. The interactions in the brain that translate out to one's state of mind are not necessarily correlated with the simple total amount of particular neurotransmitters. I'm not a neuroscientist but my guess is that there is a good spread of natural variation in global neurotransmitter levels and that two people with rather different neurotransmitter level profiles can report similar moods while people with similar profiles can report very different moods. If it was clearcut, scientists would be reporting conclusive findings to that effect long ago (and wikipedia would have the info in the relevant articles). I think it's fair to say that scientists pretty much don't know how biochemical interactions in the brain scale up to things like mood although there are some decent theories as to what factors are relevant. Sifaka ^talk 03:19, 17 March 2009 (UTC)

While I'm far from an expert on this, I'm pretty sure your premise "do trigger the release of those chemicals, they do not increase or decrease production (apparent from exercise, stress, eating habits, and drugs)" is incorrect. When neurotransmitters are released they are eventually replaced. It's not like you can use up all of your neurotransmitters in the long term and never have them again (in the short term obviously the level may get low). In any case there is also the fact there is bound to be some natural turnover (it's all very well having the neurotransmitters but there's clearly a big difference between when they affect you and when they don't) and I'm pretty sure some studies have shown you can get an increase in the baseline level with things like exercise etc. Also I don't think it makes much sense to say "One of the twins might have events that trigger lots of happiness in short bursts while the other has a more constant rate of happiness, but they should both experience the same total amount" for starters how the heck do you quantitise hapiness like that and secondly why can't one of the twins have events that trigger lot of happiness while also having a high constant rate? Nil Einne (talk) 11:18, 17 March 2009 (UTC)

There is some research that indicates a persons "happiness" measured by a variety psychological tests is rather resistant to most environmental influences. People who are happy are happy despite what happens to them and people who are sad are sad despite what happens to them. This is also true for self-confidence and a number of other moods/personality traits. This means regardless of what people do they won't be substantially happier. So the levels of neurotransmitters might fluctuate but they keep a steady average, a baseline. Grounding this phenomenon to biological/chemical basis is only reasonable. I wouldn't know how to cite any of this.--OMCV (talk) 11:44, 17 March 2009 (UTC)

Anyway what's the point of pursuing happiness? You might as well drug yourself up as do something so pointless with your life is my feeling. Though I guess I'm fairly happy anyway so it's no great deal to me. Dmcq (talk) 12:24, 17 March 2009 (UTC)

The idea is mentioned in happiness where it says "The happiness set point is a notion proposed by Lykken and Tellegen that we all have a baseline level of happiness that we return to. Although good and bad events may shift us from this baseline temporarily, we cannot permanently increase or decrease our happiness levels in the long term. Others have since challenged this pessimistic view, some drawing on neuroplasticity as evidence that our happiness level is not set in stone." although the reference looks crap. But better [1] and [2]. From a brief skim thorough, neither appear to accept the notion that happiness is a permanent unchangable baseline so there's no point trying to increase happiness. Instead they suggest people go about it the wrong way. (The second also notes there are some events which lead to a permanent reduction in the baselione.) Indeed the fact that we know our happiness can change even if only temporary is in direct contrary to the original OPs contention and IMHO suggests it's unlikely we should think happiness is an unchangable baseline so don't bother trying to change it. The notion of a baseline means that eventually people normally adapt back to their baseline. It does not mean that the happiness they had was irrelevant. It's not like their go thorough a period of sadness to pay back for the short term happiness. Clearly someone who has no blips would have been 'less happy' (if you really want to quantitise it like that) then someone with the same baseline with several happiness blips. Even if you can never change your baseline, the fact that you have had quite a lot of blips in your life seems significant to me. Note neither of the references mention neurotransmitters at all, not surprising IMHO since our understanding of human psychology and how that relates to the way the brain works is still way too much in it's infancy to go making such bold assertations. So I still stick by most of my original post, if you really want to talk about neurotransmitters our a happiness blip may result in a temporary increase in the production of neutrotransmitters. It may not result in a permanent increase (I didn't suggest it would) but there is likely to be an increase. Over time, the level usually comes back to normal (or alternatively we adapt to a permanently higher level, do we know which?) but it's still incorrect to suggest it doesn't result in an increase in the short term. Now as for the second part while I may have been slighly inaccurate in my suggestion you can have a higher constant level (or baseline) the fact remains the twin who has many blips of happiness is likely to have had more 'happiness' then the twin who had a constant level. The twin with the blips doesn't reduce their level to compensate rather the normal level remains static with blips except the other twin doesn't have blips. Now obviously there is a risk when you have blips of happiness you're going to have blips of sadness (dating someone, ooops you broke up; going on a trip to *name location here*, ooops kidnapped and held for ransom) but that's surely a different issue. (In any case, it seems to me that any consideration of achieving happiness should not start of from the notion that you have similar "exercise, stress, and eating habits" since surely these should be a consideration in persuing happiness. Nil Einne (talk) 21:01, 17 March 2009 (UTC)

Flashbangs

How do flashbangs work? How can they make a person temporarily blind and make the ears go numb? —Preceding unsigned comment added by 116.71.46.119 (talk) 17:18, 17 March 2009 (UTC)

Did reading the flashbangs article help? DMacks (talk) 17:28, 17 March 2009 (UTC)

(After ec) The entry for Stun grenades in our hand grenade article explains how they work. In brief, they use a bright flash of light that activates all photosensitive cells in the retina combined with loud blast that disturbs fluid in the semicircular canals of the ear.- Eron^Talk 17:30, 17 March 2009 (UTC)

car farts

When I turn the steering wheel of my 2005 Ford 500 all the way in one direction, moving at a slow speed, like backing up or easing into the garage, I sometimes hear a noise that sounds like a fart. I'm thinking it might have to do with the power steering. What do you suppose might be happening? --Halcatalyst (talk) 20:14, 17 March 2009 (UTC)

I've had this before, my tire was rubbing against the wheel well. 192.45.72.26 (talk) 20:42, 17 March 2009 (UTC)

There are actually MANY possibilities:

• An tire that's about to fail due to tread-separation.
• A tire that's rubbing against the wheel liner (but WHY? is the important question - has a plastic wheel liner come loose? Is your steering badly screwed up? Did you recently change wheels or something?)
• The plastic shroud around the steering column may be catching against the steering wheel.
• At the extremes of travel, you are stressing the power steering to the max - and if you try to steer 'past the end-stop' then "very bad things" can happen to it.
• If the noise is coming from behind you then it could be a problem with the differential.

It would help to eliminate some of these if you could try to have someone push the car while you turn the steering that hard with the engine turned off and the drive in neutral. If it doesn't make the noise then that eliminates the power steering. You can usually remove the plastic shroud around the steering column with just a couple of screws and eliminate that. Knowing where the sound is coming from would be fantastically helpful...if you can get someone to stand outside the car while you slowly drive in tight circles in a parking lot or something - they can listen at each corner and perhaps identify the sound's location. SteveBaker (talk) 21:07, 17 March 2009 (UTC)

If the RefDesk doesn't give medical advice, should we also refrain from providing automotive advice and suggest that the OP seek an evaluation by a professional mechanic?  :)

Actually, it would seem to make sense given the possibility of a car accident resulting from a serious mechanical malfunction. —Preceding unsigned comment added by 64.91.177.4 (talk) 23:23, 17 March 2009 (UTC)

I suspect that the issue of medical and legal advice is likely because of legal reasons, as while an individual might be correctly certified to give such advice, there is no convenient way to determine that. Are there laws against uncertified individuals giving auto repair advice in the same manner as giving medical advice without a license? I rather doubt it. 65.167.146.130 (talk) 13:32, 18 March 2009 (UTC)

There's also the risk of real harm. That applies here. Doesn't matter if its legal or not. If there's a risk soemone could be harmed from dud advice - then we shouldn't be offering it. Mattopaedia ^{Have a yarn} 05:11, 19 March 2009 (UTC)

Then we shouldn't give advice on dieting, exercise, carpentry, or anything involving someone moving, or coming into contact with anything, as there is risk in nearly everything anyone ever does. If all else fails, I say use common sense. 65.167.146.130 (talk) 14:05, 20 March 2009 (UTC)

I promise I won't sue you guys! IMO the restriction on legal and medical advice is a matter of not having a license. Someone could check over on the Humanities desk, but I'm pretty sure. I'm completely certain I appreciate the advice you've given here. Thanks! --Halcatalyst (talk) 14:36, 20 March 2009 (UTC)

Argh! How can we discuss this so many times, and still people think we don't give medical or legal advice simply because we're afraid of legal consequences? I strongly suggest that anyone taking part in this thread who thinks we don't give this advice because of legal concerns/not having a license goes to the talk page and reads through a few posts. Ask there if you are unsure about anything. 79.66.127.79 (talk) 22:08, 20 March 2009 (UTC)

I was trying to be a tiny bit satirical in my post, not to stir up a hornet's nest... the point is exactly that this is a "reference desk" not an "advice desk". Some advice-giving is probably inevitable, but when it comes to things that are inherently dangerous (medical and legal things being paramount, but not excluding other things) we should probably refrain.

@65.167.146.130 - there are no laws against giving medical advice on a message board without a license. Anyone can give any advice or make any diagnoses or recommendations that they'd like, so long as they don't purport to be practicing medicine (i.e. engaging in a physician-patient therapeutic relationship). There are regulations against practicing medicine without a license. Most state medical boards also have regulations (or at least ethical guidelines) against licensed practitioners giving medical advice or recommending treatment to people who are not personally their patients -- which would apply to this type of answer board. But that isn't the point. The point is that we should be offering solid references that answer questions, not simply personal anecdotes, no matter how well thought out. IMHO. —Preceding unsigned comment added by 64.91.177.4 (talk) 14:12, 21 March 2009 (UTC)

Astronomy/night sky question

Hi, I have one of those awful, "I saw something, what was it?" questions. I hope someone can give me some clues though.

Tonight (while waiting for a bus) I saw 2 lights in the sky. 1 was about the brightness of bright stars (eg. the 3 of orion's belt), and another to the lower right of this one was fainter. I feel as though there may have been a faint line connecting the two, but can't be sure. Orientation shown here:

*1 bright

    *2 faint

They moved up and left together, relative to stars. As they did, first "2" faded and disapeared, then the brighter light also faded, became redder, and disapeared. The distance between the 2 lights was 1-2 thumb widths at arms length. The speed they moved was about the speed of other planes (that were also visible in the sky), but they seemed to be too far apart for this obvious explanation. Also their fading and changing colour makes me think it probably wasn't a plane.

Oh, this was in Germany (Berlin-ish), facing South to SW ish. Not very high in the sky, I only just had to tilt my head back to see it clearly. About 8-8.30pm 17/3/09.

Any suggestions, or requests for clarification? Thanks!

77.12.14.73 (talk) 21:41, 17 March 2009 (UTC)

It appears you were lucky enough to catch a glimpse of the Space Shuttle as it approached the ISS. This site indicates that the IIS was briefly visible in your area, and I would expect the Space shuttle to be nearby. -- Tcncv (talk) 22:12, 17 March 2009 (UTC)

I don't know precisely what you saw (Tcncv's suggestion is possible), but they certainly sound like satallites. When they faded and disappeared that was because they were moving into the Earth's shadow - they turned red for the same reason the moon appears red during a lunar eclipse, the light reflecting off them has travelled through the Earth's atmosphere to get there. The fact that there were two of them could mean with was the ISS and Space Shuttle (although I would expect the ISS to be quite a bit brighter than the stars that make up Orion's belt), or it would just have been coincidence that two satalites appeared nearby in the night sky (they could have been at very different distances, so not very close together). --Tango (talk) 22:21, 17 March 2009 (UTC)

According to this report, the shuttle was scheduled to dock with the ISS at about 16:12 CDT (UTC-5), which would have been about 22:12 your time (UTC+1). The sightings web site indicated that both would have been visible simultaneously between 20:09 and 20:11 local time, so it's pretty clear that's that you saw saw the the space shuttle Discovery as it approached the IIS for rendezvous as part of mission STS-119. I've seen the ISS pass overhead before, and it appears like a bright star, maybe not quite as bright as Venus. The apparent motion is comparable to a high flying passenger airliner. The same site I referenced above can be used to predict sightings just about anywhere else on earth, as long as it is withing the latitudinal extent of the orbit. -- Tcncv (talk) 23:03, 17 March 2009 (UTC)

The separation mentioned sounds about right for 2 hours before docking, so I agree, that's almost certainly it. A lucky sighting! I've seen the ISS too, it's very bright (brighter than any star, I think) - I expect the OP misjudged the brightness (easily done if you aren't don't have much experience with astronomy). --Tango (talk) 23:12, 17 March 2009 (UTC)

For comparison, the Apparent magnitude article puts the ISS close to Venus in brightness, depending on the angle of the station and the phase of Venus. -- Tcncv (talk) 23:27, 17 March 2009 (UTC)

The ISS is already a pretty good naked eye object - it crosses the sky in a matter of a minute or two - so it's easy to mistake it for an aircraft or something. Just before dawn or just after dusk when the sun is at the right angle to have it be sunlit in an otherwise dark sky - even with the naked eye, you can see it's not just a bright dot - it has quite visible 'wings'. Before today, it has not been as bright as Venus - but while the shuttle is docked - and after it leaves in a few days and they deploy the new solar panels that it's delivering - the ISS will get appreciably brighter than Venus and stay that way. SteveBaker (talk) 01:57, 18 March 2009 (UTC)

This 2006 image at the Astronomy Picture of the Day will give you a good ideas of the apparent size. The station is several times larger now, but its roughly 100m size viewed at 350km altitude (farther if you consider the viewing angle towards the horizon) is still a fly at the end of a football field. (OK, maybe it's a big fly.) -- Tcncv (talk) 03:19, 18 March 2009 (UTC)

More like a golf ball at the other end of a football field...in proportion to a 100m football field, I make it about 3cm. But it's glowing pretty bright - it's more like looking at a lit-up light bulb at the other end of a football field - but I watched it during the last shuttle mission (it's always more visible with the shuttle docked next to it because the shuttle faces its white upper-side towards the sun so the solar collectors inside the doors can do their thing - so it's particularly reflective. For sure, I had no trouble seeing that it was more than just a dot...you could tell it has "wings". SteveBaker (talk) 05:13, 18 March 2009 (UTC)

No solar arrays on the shuttle, the inside of the doors have radiators. When docked to the station the shuttle/station stack attitude isn't determined by the sun either, instead the attitude is one where no propellant is required to maintain the attitude. anonymous6494 08:24, 18 March 2009 (UTC)