Wikipedia:Reference desk/Archives/Science/2012 May 25

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May 25

Two questions

Scientist said that Black hole pull everything even light. As I know light is made of photons which are massless, they say. How is than posible that gravity affect them? Second question. Scientist said that electromagnetic force do not affect neutrino particles. I ask how than do the experiments with neutrinos in CERN? Which force they use to accelerate them and keep them inside? They said that neutrino pass through any mater. How than keep them inside? I will be very appreciative for answer. If anybody know answer, please tell me. — Preceding unsigned comment added by Parket7 (talk • contribs) 00:11, 25 May 2012 (UTC)

Photons don't have zero mass, they have zero rest mass. You should know that mass and energy are identical, so having mass means the same thing as having energy. Since photons have energy, they have what is called relativistic mass which is why they are affected by gravity. They are subject to gravitational lensing for example. The fact that gravity affects photons explains why they can't escape a black hole: the path the photons travel get "bent" as they pass any other mass, and black holes have enough gravity to "bend" their path inward, so they can never escape. As far as neutrinos: neutrinos have a very tiny, but non-zero cross-section, which means that, while the likelyhood of a neutrino interacting with another particle is very very small, it isn't zero. So, while you are being bathed in uncounted trillions of neutrinos every second, every few years one of them might interact with one of your atoms. It isn't much, but it is enough to prove the exist and catch one once in a while. Being electrically neutral doesn't mean that something is hard to catch, neutrons are fairly easy, and have no electrical charge of their own. --Jayron32 02:37, 25 May 2012 (UTC)

Black holes (or any massive object) can bend light. Isn't there a threshold for how close a photon can get to a black hole without getting "sucked in"? I'm assuming it has something to do with an inverse-square relationship, but my brain is getting foggy at this point. ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:29, 25 May 2012 (UTC)

That would be the event horizon. 203.27.72.5 (talk) 06:20, 25 May 2012 (UTC)

Indeed, photons are no different to anything else - the event horizon is, by definition, the closest they can get and still escape. The photon sphere is an interesting related phenomenon. --Tango (talk) 12:24, 25 May 2012 (UTC)

What accounts for temperature increase at night in a modern home?

I live in the UK. Hot day today. But hotter night, at least in this room. No air-con.

Is it heat beating down on the bricks outside during the day, the bricks absorb it, and are now releasing that heat into the room? I've also heard that cloud cover can trap heat, could that account for it? What if we assume no clouds? --bodnotbod (talk) 00:40, 25 May 2012 (UTC)

Are you describing real, measured temperatures, or how hot you feel? HiLo48 (talk) 00:46, 25 May 2012 (UTC)

He's describing how hot I feel.

To throw some numbers around, today in the UK the air temperature (outside) reached about 26C at about 5pm where I live. An hour or two later, the temperature inside my living room (not especially well ventilated) reached 23C.

Right now at about 2am, the air temperature outside is about 15C (an unusually warm night, for here). The temperature inside my living room is *still* (probably unsurprisingly) around 23C. So it's not more, but nor has it gone down appreciably. Humans tend to perceive this as "hotter" because it's during the night, maybe? --Demiurge1000 (talk) 01:00, 25 May 2012 (UTC)

Yeah, the heat stored in the bricks (and other parts of the building) would be a big part of the problem. Better ventilation would be a great solution, but maybe not practical. (If you have ever contemplated moving to Australia, please check our climate carefully. You may not like it.) HiLo48 (talk) 01:12, 25 May 2012 (UTC)

If you have electrical theory knowlege, the phenomena of some homes/rooms being hotter at night is very easy to explain. Before I try and put it in simple terms, don't forget that we have eveolved in a world where is is cold at night and cold in winter. The body feels comfortable with some natural diurnal and annual variation. If, for instance, you are in a room during the day at 25 C, you can feel cool, and if you are in a room at night at 25 C, you can feel hot.

The structure of a dwelling (eg bricks) provides thermal resistance, analoguous to electrical resistance. The flow of heat thru a resistance is restricted. The dwelling structure (and furniture inside) also provides thermal capacitance, analogous to electrical capacitance. That is, heat is stored. The two phenomena act to together like an electrical filter circuit comprising series resistance and shunt capacitance (see passive low pass filter at http://en.wikipedia.org/wiki/Low_pass_filter). Such filtering delays the incident variation. A simple room can delay the diurnal variation by a maximum of one-quarter of the varition period - ie 24/4 = 6 hours (an electrical engineer might regard this as a 90 degree phase shift). If the structure has a rood space or other rooms, it can act as two simple passive filters in cascade. In this case the maximum possible delay is 12 hours. However, a more likely total delay in a double brick dwelling with good ceiling insulation is about half that, ie around 6 to 8 hours. Wickwack124.182.14.180 (talk) 01:47, 25 May 2012 (UTC)

I generallly find evolutionary explainations quetionable particularly when not backed up by anything but 'it sounds right'. But in this case, it doesn't even sound right. Specifically who's 'we'? Plenty of humans have been living in regions close enough to the equator not to have the seasonal variation you speak of (they may still have seasonal variation although generally far less extreme and not of the same character). And while there is still diurnal variation, it's generally far less then I'm guessing you're thinking of, particular in sheltered areas (i.e. out of the blazing sun). Nil Einne (talk) 13:12, 25 May 2012 (UTC)

A certain room in my house (on the top floor facing west) absolutely gets hotter at night, if the windows are kept closed. I open the windows and put fans in them on high (half blowing in and half out). I leave them on for hours. Otherwise, I find that when I turn them off, the heat radiating from the west wall and ceiling heats the room right back up again. (I previously tried using a window A/C unit in there, but it ran continuously and couldn't keep it cool.) A 6 hour delay is just about right. Since the hottest part of the day is around 3 PM, the hottest temp in that room occurs around 9 PM. And yes, this is a brick house.

If you can't ventilate with fans, you could also try hosing down the outside of the wall at the hottest parts of the day. If you have a sprinkler system, set that up to spray on the wall. StuRat (talk) 03:49, 25 May 2012 (UTC)

The term is thermal lag. It can be exploited to good effect in places with high daytime temperatures and low nighttime temperatures (as in mid-altitude deserts), where it evens temperatures out. Adobes in New Mexico use mass to maintain an even temperature, for instance. It's specifically used in passive solar building design. Acroterion (talk) 03:56, 25 May 2012 (UTC)

I think that the effectiveness of opposite openings is often overlooked. A room with a fan still diffuses heat from one point. But a room with windows open to the east and west and even a slight prevailing wind, without any fan, will exchange its entire volume with the outside as the air moves along downwind. Wnt (talk) 04:48, 25 May 2012 (UTC)

I was talking about multiple fans, with some blowing in and some out, which exchanges all the air without the need for (natural) wind. Since my fans blow at the speed of a strong wind, on high, they should be more effective than a slight breeze. StuRat (talk) 04:55, 25 May 2012 (UTC)

If they are blowing in and out of the same window, then you may not be getting much air flow in the rest of the room. You would be better off opening a window on the other side of the building and leaving the doors open between them. You can use fans to increase the airflow if there isn't much wind, but you don't need much to get a big effect. --Tango (talk) 12:21, 25 May 2012 (UTC)

No, they are not the same window, for many reasons. Beyond the inefficiency that would cause, two of these box fans would never fit into one of my windows. The only rooms in the house which have only one window are the bathrooms. StuRat (talk) 16:08, 25 May 2012 (UTC)

Thanks very much for the answers folks. HiLo, my question related to measured temperatures as I have a thermometer in the room. I have done the opening windows across the house before and in spite of intervening walls dividing the rooms it does seem to work very well. --bodnotbod (talk) 12:35, 25 May 2012 (UTC)

My lounge room heated up considerably last night, after I switched the lights on. I have three 60W traditional globes and I was doing some close work and need to see. I'm surprised the temperature increase was noticeable. It was hot again today, and I've found a lab thermometer at work, so I'm going to see exactly how much switching the lights on warms the room. --TrogWoolley (talk) 13:18, 25 May 2012 (UTC)

You've raised a good point there. Yes, we use lights at night, and modern, energy efficient globes create a lot less heat than traditional globes. It's certainly made my poorly located home office here in Australia a lot more usable on hot summer nights. HiLo48 (talk) 17:41, 25 May 2012 (UTC)

Now would be a good time to replace those incandescent bulbs with compact fluorescent lamps. Not only will you save on energy, but you can also be more comfortable. And, if you elect to go with 100 watt equivalent blubs (which are really 23 watts), you will still save energy and also get more light. StuRat (talk) 17:50, 25 May 2012 (UTC)

Switching the lights on last night made it feel warmer, but the temperature in the room did not rise, indeed it fell during the hours I had the lights on. I must be feeling the radiant as I'm sitting right under the bulbs. It is time to change to these new-fangled ones! --TrogWoolley (talk) 16:26, 26 May 2012 (UTC)

Agreed. I imagine you could make the thermometer detect the radiant heat by covering it in a black cloth and placing it where the light shines. There could also have been a rise in humidity as you sat there, especially if you were sweaty. This would make it feel warmer, too. StuRat (talk) 17:00, 26 May 2012 (UTC)

Orange Plasma on ICP-AES

I've noticed something strange when analysing some water samples on an ICP-AES. Usually, when looking through the filtered viewing port into the plasma chamber, the torch appears to give off a deep green light. For some reason, these water samples change the colour to a bright orange. Generally, I don't get samples with high sodium content. I can't test for sodium with the methods set up on this instrument, but is it possible that high levels of sodium ion are causing the colour change? If not, what constituent could be causing the change? I'm also frequently encountering an error that the plasma impedence is too high. Could this be caused by the same thing that's causing the orange glow? 203.27.72.5 (talk) 06:15, 25 May 2012 (UTC)

I don't have any experiential knowledge of the apparatus, but could Rayleigh scattering or Tyndall effect be involved? {The poster formerly known as 87.81.230.195} 84.21.143.150 (talk) 12:08, 25 May 2012 (UTC)

The Tyndall effect is out, as it applies to colloids, and I think Rayleigh scattering is highly unlikely, given that the light is only travelling about 30cm to reach my eye, and that the plasma has a lower electrical polarizability than air (since it's already substantially ionized). 203.27.72.5 (talk) 21:04, 25 May 2012 (UTC)

The chances are that it is sodium. Sodium in plasma only needs ppm quantities to have a yellow glow. Normal tap water will have enough. Graeme Bartlett (talk) 13:09, 28 May 2012 (UTC)

Hand clap

Is it true: when you clap your hands, at the moment of contact, temperatures in excess of a couple thousand Kelvin are generated for someting like a nanosecond? Plasmic Physics (talk) 09:21, 25 May 2012 (UTC)

That seems highly dubious, in order to reach such extreme temperatures you would need to concentrate a lot of energy in a very small volume very quickly. For example, there is a theory that temperatures over 9000 K are reached in cavitation, but that is in the center of a bubble which is imploding with supersonic velocities. Yoenit (talk) 11:02, 25 May 2012 (UTC)

Has PlasmicPhysics caught that Dorothy Dixer disease from WhoopWhoop? I suspect, given Plasmic's background, that he is aware that questions on the temperature rise caused by clapping, banging two bits of wood together, and the like, is a favorite amongst those who write college and undergrad physics textbooks. For those not familiar with the British parliamentary system as used in Britain, Australia, and elsewhere, a "Dorothy Dixer" is where someone asks a question to which he already knows the answer (or, alternatively, asks a question so that a colleague can answer in order to look good. The temperature rise possible is fractions of a degree, and is easily estimated from calculating the kinetic energy (mass of arm/hand, and velocity at impact), and the specific heat of flesh, assumed to be as per water, and a couple of other simplifying assumptions. Ratbone124.182.7.166 (talk) 11:38, 25 May 2012 (UTC)

There's an article about that, BTW OsmanRF34 (talk) —Preceding undated comment added 16:09, 25 May 2012 (UTC).

It's probably going to depend on your definitions. Temperature is defined as an average, so if you talk about the temperature of a very small amount of matter over a very small timescale, then you can easily get extreme results, but they aren't particularly meaningful. --Tango (talk) 12:01, 25 May 2012 (UTC)

In special circumstances in theory, maybe. But in this case, upon impact the skin and some meat/gristle etc to a depth of a couple of mm or so gets deformed at the speed of closing. Within the context of the question, you can consider a peak temperature at a small point if you like. An average temperature is not implicit in the question. However the kinetic energy is dissipated over a volume of flesh equal to (roughly) area of hand multipled by depth of deformation. So it's not a very small amount of matter, it is a significant amount of matter with respect to the amount of kinetic energy. The time taken to deform the flesh is not infintessimal either, but can be assumed short enough that heat lost by conduction to surrounding tissue can be ignored. So you can't get extreme results. Ratbone124.182.7.166 (talk) 12:35, 25 May 2012 (UTC)

(edit conflict)I don't see why you made such a fuss about me asking the question. I'm satisfied with this answer, and unlike big Whoop, I'm not asking questions because I'm bored, or because I have an alterior motive. I'm genuinely interested in the answer. Plasmic Physics (talk) 13:01, 25 May 2012 (UTC)

No big deal Plasmic, I gave you the answer anyway. But I was a bit supicious, given that your own userpage says you are a Bsc, and your answers to other questions indicate you have good physics knowlege. As I said, questions on the temperature rise of hands on clapping, or temperature rise of bits of wood banged together, and the like are common in textbooks. Three of 4 physics books I own have a question asking for a calculation of temperature due to clapping; the 4th (the famous Halliday & Resnick dreaded by uni students thruought the English speaking world for 30 years) asks you to calculate the temperature of a nail after it has been hit by a hammer. You must have seen a similar question. Ratbone60.230.194.187 (talk) 15:15, 25 May 2012 (UTC)

But that considers the temperature after the heat has dissipated through part of the flesh. But what about before that? As I understand it, the air between the hands is compacted to a very high pressure, and because only a very tiny amount of air is trapped between the hands (and that air has very little mass to begin with), a small amount of energy can theoretically heat it by thousands of degrees. I do agree with Tango that such a 'temperature' may be quite meaningless, though. - Lindert (talk) 12:55, 25 May 2012 (UTC)

Just how quickly can you clap your hands? Dissipation of heat occurs on a nanosecond scale, much faster than the pressure can buildup. I wouldn't be surprised if deformation of your hand is also faster than pressure buildup, which means you never get a high pressure by clapping, just a deformed hand (no pun intended) Yoenit (talk) 14:07, 25 May 2012 (UTC)

You're probably right that heat dissipation is faster, I've never done the calculations (I was just speculating a bit). And yes, although there is definitely a local increase in air pressure (hence the sound), it's impossible to calculate how much without knowing how the hands deform. - Lindert (talk) 14:56, 25 May 2012 (UTC)

If you do do some calculations, or just think about things, like the amount of energy required in a loudspeaker to produce a clap sound of equal loudness, you'll find that the energy converted into sound energy is quite small compared to the kinetic energy delivered by the mass of the arm/hand. Therefore almost all the kinetic energy must be absorbed in the deformed flesh. As to how much the hands deform, just clap and see - it is limitted by the essentially rigid bones and is of the order of one or 2 mm. As the bones do not deform, they absorb no energy. Just how the hands deform beyond that simply does not matter. Ratbone60.230.194.187 (talk) 15:15, 25 May 2012 (UTC)

I remember reading somewhere that the sparks that are generated in a grinding machine have a temperature of thousands of degrees but are harmless to the human skin due to low heat content (because of low mass). This question is similiar to this. WikiCheng | Talk 14:00, 25 May 2012 (UTC)

Steel striking stones such as flint and quartz produces ignition temperatures high enough to occasionally ignite a few steel bits that fly away, forming the sparks we see, and there may be lots of clanking of the fairly hard hand-jewelry in a crowd... hummmmmm. One can produce these sparks with the force of ones hands and according to a quick google search, the ignition temperature of steel is 1500 degrees Fahrenheit, so we are somewhat near the ballpark here of a couple of thousand degrees. Modocc (talk) 15:37, 25 May 2012 (UTC)

It depends on how far they travel before hitting the skin, since objects that small rapidly cool while flying through the air. StuRat (talk) 16:04, 25 May 2012 (UTC)

It's not true, you can easily check this by clapping your hands in total darkness when your eyes are fully dark adapted. Temperatures in the thousands of kelvins range even confined to a very small area near the surface, should lead to ionization which should be easily visible. Count Iblis (talk) 16:44, 25 May 2012 (UTC

Without any jewelry you are right, and the OP didn't specify whether or not any is worn, but we have ample evidence that one can attain fairly high temps when hard jewelry is in place (which where I live is very common). Maybe not thousands of kelvin, but within the same order of magnitude 800+K. --Modocc (talk) 17:08, 25 May 2012 (UTC)

There is a phenomenon that produces extreme temperatures (confirmed up to 20,000 K!) on picosecond scales: Sonoluminescence. However in this case it is a completely sealed system with a much denser, incompressible fluid (water); I doubt the same effect would even be close to the same scale in a non-sealed system such as the "hand clapping" one. -RunningOnBrains^(talk) 20:12, 25 May 2012 (UTC)

Some background to this. Suppose I am hand clapping in the dark with gloves studded with quartz and steel. I will definitely see plenty of sparks! There is no question about this. For as a child I've personally, on numerous occasions, out of mere fascination and curiosity, easily sparked the edges of rocks with the edges of metal implements using very little to moderate force. According to our article on sparks, those sparks I created are burning bits of steel. If I remember correctly, from chemistry, ignition temperatures are needed. Thus, the sparks would not be observed unless I was initially creating these very localized and very high temperatures with these experiments. Perhaps someone that is more knowledgeable can correct me if I am in anyway wrong on this and my conclusion that its indeed possible and even probable, of course. --Modocc (talk) 20:40, 25 May 2012 (UTC)

Yes, in that case what happens is that the energy that is deposited locally at the contact area cannot get away easily, small parts break off and they have very high temperatures. However, this does not happen with your hands. In a biological system that has to maintain itself, that would create big problems. Count Iblis (talk) 22:18, 25 May 2012 (UTC)

Of course ones flesh would not and could not get very hot (clapping can warm the hands, and heart, though :-))! I never said or implied that it would. However, I've struck my terrible synthesis because its unclear from what I've read so far how hot the metal sparks can get cause I'm a too tired, too rash and why the blazes I am misreading stuff beats me. In fact, its starting to dawn on me, only now of course, that I made this exact same mistake of conflating "red hot globules" with combustion, once before... in a distant memory decades ago when I didn't know better and so I was obviously doomed and predisposed to repeat this mistake. I can't seem to stop repeating the same spelling mistakes either. :( --Modocc (talk) 22:36, 25 May 2012 (UTC)

Followup. In the very short time I've been trying to find out more about the actual temperature and any combustion of such sparks, I'm only more confused and befuddled, so any reliable sourced info would help. My sinus pain is getting worse too, so I need to take a break. Thanks in advance. PS, One source, not a reliable one though, indicated that sparks are propelled by an initial conflagration, which may explain my confusion, since there would be an initial combustion that expels the extinguished globules that the article mentions, but I've not read the lengthy source referred to yet. The metal alloy Ferrocerium does actually burn very hot, 1,650 °C, and has a relatively low ignition temperature, between 150 and 180 degrees Celsius. I'm still unclear about ordinary steel though. I just picked up a couple of quartz stones (I couldn't quite remember, so I was reluctant to assert this), and confirmed that knocking them together produces sparks too, and I've no idea how hot these are either, but probably not very hot since they are not used to start fires and the quartz has piezo-electric properties. I suppose too that iron can oxidize at different rates and temperatures, so there is no simple answer, other than to look for more data on this. --Modocc (talk) 00:02, 26 May 2012 (UTC)

It doesn't have any relevance to the OP's question, but if you see something glowing, eg sparks given off by striking metals and/or minerals together, you can quite easily estimate the temperature, using the principle of black body radiation http://en.wikipedia.org/wiki/Black-body_radiation. Black body radiation sensing is most accurate when the item that is radiating is "black" ie totally absorbent. If it is not, the apparent temperature indicated by the radiation is lower than the true temperature. If the item is transparent, the apparent temperature is zero. In practice, most metals and minerals are sufficiently close to being black body radiators. Alloys of iron are very close, aluminium is a notable exception. Dull red for steel is ~1500 C; Glowing yellow is about 4000 C. Artisans skilled in welding, cutting, and the heat treatment of metals except aluminium alloys go on the colour of the radiation as seen with their eyes - they don't bother with any sort of thermometer. Ratbone121.215.6.210 (talk) 04:18, 26 May 2012 (UTC)

Thanks Ratbone. Wedding bands and rings have been known to ignite gases such as propane and volatile vapors and if I remember correctly, platinum rings are particularly dangerous in this respect, since the metal catalysizes many reactions. Also, if I remember correctly, iron gets whiter with heat, but I was unsure about what temp it turned red. The article on sparks mentions that the spark globules from striking steel with flint are red. 1500 C is definitely above the ignition temperature of steel, so the globules must be oxidizing, at least on their surface.[striked because steel appears red at 1500F, not 1500C, per forging charts that I give below] The more I think about this, I doubt the steel's standard atm ignition temperature is entirely relevant, since local pressures may be somewhat elevated too when stones, crystals and/or ring bands bang against each other, but these effects are too transient to be significant normally. This study measured a fairly high ignition temperature for foils (preceded by some self-heating). --Modocc (talk) 06:59, 26 May 2012 (UTC)

The color that any hot substance glows is directly dependent on its temperature; see blackbody radiation. However combustion is a whole different animal, as a substance can have emission lines that change the color of the flame; for instance, sodium burns a brilliant orange, and iodine burns purple. See flame test for info on that. -RunningOnBrains^(talk) 07:54, 26 May 2012 (UTC)

I don't think that, for steel at any rate, the ignition temperature or radiation due to combustion is significant. If it is significant, then an awful lot of metalworking textbooks must be wrong. A quick google for "ignition temperature of steel" turned up all manner of unreliable sites giving temperatures from 800 C to 1500 C. However, to burn the Fe and C, you've first got to melt it, and the melting point for steel is around 1500 C. Really, only a gas can burn. Things that are not gasses burn because the heat of combustion is sufficient to pyrolyse (ie split up chemically with the pyrolysed products being gasses) the liquid or solid, or just vaporise it. The paper cited by Modocc is not fully accesible to me without paying for it, but appears from the sample page to be for pure oxygen, and they give the ignition temperature as >1600 C. Ignition temperatures for solid are gnerally much higher in air than for pure oxygen. Ratbone121.215.6.210 (talk) 08:21, 26 May 2012 (UTC)

I might need to modify my last post accordingly and will note too that I need to be more careful with googling random sites, because the net is both a blessing as I've more access than ever to obscure stuff and interesting discussions, and a curse too sometimes. In any case, you are correct about the pure oxygen, but the study here gives 1644K or 1391C for the cylinders and also gives a considerably lower surface temperature, 1233K, or 950C for foils which is significantly below the melting temperature and involves less mass. Thus I'm still left wondering if, according to some random guys on the net I've read, these iron particles that were at one time used to start fires have some if any self-heating due to oxidation. According to this random off the net chart steel turns red at a temp of only 760C! It then turns orange and orange-yellow as it gets hotter and, according to the description given, it says an oxidation layer forms???? Another more subtle chart confirms the other sites temps at least, so I'll assume instead of the figure of ~1500C you posted earlier, 1500F would be more accurate (and this explains some of the confusion). --Modocc (talk) 10:03, 26 May 2012 (UTC)

Oops! Our wikipedia article black body radiation http://en.wikipedia.org/wiki/Black-body_radiation needs some attention then, see the colour chart. However, the lower temperatures aprently required for balck body emission means that my thought that combustion can be neglected when assessing the temperature of hot metals is confirmed more strongly. Ratbone121.215.6.210 (talk) 12:37, 26 May 2012 (UTC)

Jupiter Rise?

Which way does Jupiter appear to cross the sky when it's visible in the Northern hemisphere? West-East or East-West? — Preceding unsigned comment added by 92.40.254.195 (talk) 11:43, 25 May 2012 (UTC)

Could be either one, depending on whether it's in "retrograde" motion as seen from the earth. ←Baseball Bugs ^{What's up, Doc?} carrots→ 11:52, 25 May 2012 (UTC)

Given the title "Jupiter Rise", I would guess the OP is talking about movement within one night. That is caused by the Earth's rotation, so it's east to west, like everything else. Movement between nights could go either way, depending on whether the Earth and Jupiter are relative to each other in their orbits, as you say. --Tango (talk) 11:58, 25 May 2012 (UTC)

Yes. The only things that rise in the west are prograde satellites below synchronous orbit, like Phobos. —Tamfang (talk) 21:09, 25 May 2012 (UTC)

Sunny weather and arthritis

Many arthritis sufferers say that their symptoms are eased to a large extent by hot sunny weather. Can anyone enlighten me as to the mechanism that might effect this please?--TammyMoet (talk) 13:41, 25 May 2012 (UTC)

There is probably no medical or clinical reason to explain that, although it is perfectly believable. My first instinct is simply that everybody loves "good" weather (I'd far prefer a raging blizzard to 28C and sunny, but I'm in a vast minority), and whereas when the weather is bad people tend to remain around their homes without much physical activity, summer-like conditions draw people out and about. Now, arthritis patients may begin to feel better for any of several reasons: doing things like swimming and gardening take the mind off mild to moderate pain and make it seem less substantial; the sunny weather simply improves the psyche, making it harder to dwell on painful symptoms; or potentially that increased levels of outdoor activities work to liberate joints and muscles, reducing stiffness and pain. These are the most likely scenarios. From a meteorological point of view, sunny weather is associated with sinking atmospheric motion, ie. high pressure, and many patients report that their pain worsens in bouts of low pressure/storminess. It's conceivable that during extended periods of fair weather, symptoms nominally lesson until the next trigger of pain. Juliancolton (talk) 13:56, 25 May 2012 (UTC)

I agree with the air pressure as the cause. Higher air pressure will tend to reduce swelling somewhat. StuRat (talk) 15:49, 25 May 2012 (UTC)

I doubt that. Pressure will generally cancel out. What may have an effect is changing air pressure, since it takes time for pressures in internal cavities, etc., to equalise with the air pressure. That means when air pressure changes quickly (as it does immediately before a storm), there will be a short time when the internal pressure and the external pressure aren't equal. Then there will be a net force, and you may be able to feel it. (It's a mild version of what happens on a plane, so that would be a good test - how to arthritics generally find take-off and landing on planes?) --Tango (talk) 12:49, 26 May 2012 (UTC)

Being a sufferer, physical activity usually exacerbates arthritis. But blood is warmer so it flows faster and higher pressure means more oxygen in the air. Could help ease pain.165.212.189.187 (talk) 15:27, 25 May 2012 (UTC)

Ambient temperature has very little effect on core body temperature of a healthy individual. Your extremities may vary in temperature, but I don't think the blood would change temperature enough going through them to have a noticeable impact on its viscosity. The higher pressure isn't going to lead to sufficiently more oxygen to have a noticeable impact either - changes in air pressure are generally only a couple of percent. --Tango (talk) 12:49, 26 May 2012 (UTC)

ever hear of the straw that broke the camels back? You just explained two.68.83.98.40 (talk) 02:42, 27 May 2012 (UTC)

http://arthritis.about.com/b/2008/07/09/vitamin-d-supplementation-may-offer-pain-relief.htm

Count Iblis (talk) 15:56, 25 May 2012 (UTC)

The landed gentry with their lily-white-skins may have had this conditioned diagnosed first -because only they could afford doctors. However, could it be that the average English peasant, toiling outside in all weathers was never trouble by such a malady? Vitamin D levels in modern man have been noted as poor. --Aspro (talk) 16:51, 25 May 2012 (UTC)

It could also be that peasants never got old enough to develop arthritis... or that rheumatoid arthritis was brought over from the New World... believe me I've researched this/these conditions for years (they run in my family and I'm the latest in line) and there's all sorts of weird and wonderful theories regarding how RA especially developed in the Old World. Vitamin D has recently been linked with MS and cancer as well as the obvious (rickets), so it wouldn't surprise me to see it has an effect on arthritic conditions too. My 5x great grandfather's obituary (written 1897) cites rheumatoid arthritis as cause of death. He was the only one in his generation in his family to reach the age of 60, everyone else being glassblowers or miners. Anyway, other ideas are welcome as to why sufferers feel symptoms are eased in hot dry weather. --TammyMoet (talk) 17:15, 25 May 2012 (UTC)

Yes, I am aware of the life expectancy of those time, which is why I posed it as a question, rather than come out with a statement. However, I choose the word 'peasant' with care. As you have taken the trouble look at archival records, have you noticed that they tend to 'only' record conurbations of about 5,000 souls or more? Not agricultural workers but artisans and the like. These crowded slums ran out of vegetables in late winter and scurvy was commonly recorded – especially in prisons and asylums, which bought the cheapest food stuffs. On top of that, the insanitary conditions mean that the poorer township populations were exposed to high levels of pathogenic organisms. So, this plus that lack of vitamins leads to the recently acknowledged phenomena that people whose ancestry is traceable to places like Glasgow (which was once a quaint little village on the side of the River Clyde and still beautiful even today) now have high a incidence of autoimmune disease. [1]. For the reason given above, we don't appear to have reliable records for the mortality rate of peasants in the country-side but the thinking is that it was lower for all age groups -compared with the towns and cities. Just has been observed in the wild life at Chernobyl. The population of towns and cites grew due mostly from the migration from uncontaminated country areas. Graveyards give witness to the high morality rate therein and so if half the children die before reaching puberty there can not have been the exponential growth to explain the expansion recorded without this constant influx - simple maths. Therefore, peasants didn’t develop rheumatoid arthritis because they didn’t live long enough! Rather (in my view) they remained free because there was no genetic advantage and they had year long access to vegetables (vitamin C) and sunlight (vitamin D). Rheumatoid arthritis is horrid, but I don't know of any modern medical advance that has enabled them to 'only now' survive past 60. Classic like Lark Rise to Candleford have poor old people in them. If you see my point.--Aspro (talk) 14:18, 26 May 2012 (UTC)

Not everyone will suffer from rheumatoid arthritis, which suggests a strong genetic component, and explains why not everyone in centuries gone by would have it. Osteo arthritis is a different kettle of fish and it is difficult to find any older person without some form of this condition in this day and age: I suspect this is the case in years gone by. Mortality rates aren't dependent on disease and health: living and working conditions also played a part (hence my mention of the glassblowers and miners in my family). And as for archival records, I have noticed no such thing about conurbations or the number of people therein. It may be different for other countries but England has pretty complete parish records from the mid-1500s, which predate by some way the industrialisation and urbanisation of the countryside. --TammyMoet (talk) 18:48, 26 May 2012 (UTC)

Lets put it this way: Mortality rates are dependant on having a robust and strong immune system. Individuals prone to RA, thus has a very active IS which gives them an evolutionary advantage in disease ridden conurbations. So they where able to breed like rabbits - in comparison - to their neighbours that drop like flies during every epidemic. The Selfish Gene doesn’t care if one dies at an early age, what matters at the end of the day (or generation) is that more of of their issues survive to produce more issues compared with their neighbours with bod ordinary immune systems. I don't have any references to hand but early recorded deaths seem to have been simplistic; i.e., in child-birth, fever, dropsy, apolepsy, etc,. It was not until about the 1840 in the UK when medical journals came to be published that doctors attempted to be more precise. Unskilled agricultural workers (peasants) where considered to be of little economic importance and so their maladies when under the radar. It was the country mill owner, publican and so on (those that had property) that had their cause of death registered as far as I can make out. Exceptions may have be pandemics like plague and smallpox. I'm not saying your wrong. It is I think, more of a case of interpretation. Additional, it was the city dweller that also got diagnosed with General paresis because it was unknown in the country side. Contagious diseases like this and others spread faster in highly populated areas and some became endemic. Measles is a good example, it needs a large conurbation to be endemic. Without a this, it used to follow a predictable and regular 7 year cycle.Err.. gone off at a tangent. So to finish.... Thus in rural areas, where survival depended on hard labour, families with a history of RA found it difficult to pass on their genes to other such families. So this gene pool was constantly diluted, whereas - in the cities it was concentrated until it became an identifiable medical condition. Does that make as much sense to you as it does to me? --Aspro (talk) 17:23, 27 May 2012 (UTC)

Raised temperature in itself can directly ease the pain of arthritis. ObPersonal: my grandmother suffered very badly from rheumatoid arthritis, and a treatment for temporary pain alleviation which I witnessed as a child/youth in the 60s/70s (and which I must presume was prescribed or at least sanctioned by her doctor) was for her to immerse her crippled hands or feet in barely-melted soft paraffin wax – I believe the particular wax was specifically formulated and sold for this purpose, though it's possible my grandfather (an engineer and an intelligent and resourceful man) repurposed it from another source. Paraffin wax has a high heat capacity and therefore cools relatively slowly, and the resultant gentle but persistant heat to which her hands or feet were thus subjected while immersed/encased was efficacious on the treated members.

I imagine subsequently developed drug treatments have rendered this form of therapy largely obsolete in conventional medicine (perhaps not entirely wisely, and googling suggests it is still promoted in fringe medicine), and I can't answer the OP's primary question of why sunny weather/heat helps. {The poster formerly known as 87.81.230.195} 90.197.66.211 (talk) 10:34, 26 May 2012 (UTC)

On the contrary, I have been prescribed paraffin wax treatments in the past by physiotherapists and am looking for my own personal wax bath so I can use it at home. It eases the pain in my hands for nearly a week at a time, something which no painkiller can do. --TammyMoet (talk) 18:42, 26 May 2012 (UTC)

I'm sorry to hear of your affliction, Tammy, and glad that the treatment helps. {The poster formerly known as 87.81.230.195} 90.197.66.211 (talk) 19:52, 26 May 2012 (UTC)

This page at Arthritis Research UK Can damp, cold conditions make osteoarthritis worse? supports the theory that it's to do with an improved feeling of well-being (or the other way round in this case). Alansplodge (talk) 21:18, 26 May 2012 (UTC)

Well, it's well known that depression (psychology) seems to amplify pain, and that antidepressants can be used for some degree of pain relief. Whether it really amplifies pain, and whether the drugs really help it, I suppose is harder to define... still, sunlight and indeed vitamin D specifically are thought to offer protection against depression. [2][3] etc. Wnt (talk) 21:33, 28 May 2012 (UTC)

Border control discovering smuggling inside the body

How do border control agents discover objects inside the body? Do they perform an X-ray, an ultrasound or stick a probe into people? 2 certainly seems to be the less inconvenient, but is it effective? — Preceding unsigned comment added by OsmanRF34 (talk • contribs) 16:01, 25 May 2012 (UTC)

Wikipedia has an article about this: Balloon swallower. Medical glove and large dollops of K-Y Jelly also facilitate a fast, effective and fun way, to probe you as one comes through the Immigration Gate.--Aspro (talk) 17:03, 25 May 2012 (UTC)

Sorry to spoil your fun Aspro, but it seems that the drugs packages are usually swallowed rather than inserted, so you would have to reach in an awfully long way to find them. Alansplodge (talk) 21:34, 25 May 2012 (UTC)

Fun? or are you advancing an argumentum ad ignorantia. Consider the Joe/Jane Doe. Coming back from a vacation/business trip with a little something. Are the Customs going to ignore this just because their amateurs? Will they think “we won't look there!” I have lived for many years near to an international airport.... listened to boring hours of 'shop talk'. Believe me, they don't have to look far at times and they are seldom disappointed. The grin on their faces (I think) is from the satisfaction that they are smarter than the people they given to examine. This article gives shows that smuggling is not a once in a while pastime [4]. Switch off your computer, step out your door and discover life as it actually is. Its different from CSI which is fiction. In that, thet all have manicured nails and what knot. --Aspro (talk) 15:11, 26 May 2012 (UTC)

Calm down.

You said it was "Fun" to anally probe people. He's saying that it's not an effective technique, since a human digestive tract is about twenty feet long. (Thus, spoiling your "fun", in favor of the presumably less-fun x-ray machines.) 71.235.141.252 (talk) 17:25, 26 May 2012 (UTC)

You are both missing the point. A lot of amateur smugglers don't swallow but insert -so 20 foot doesn’t figure in this and not all fliers are male. When processing thousands of people, gloves and KY jelly is cheaper for this sort of thing and the UK Border agency is under government edict to reduce costs wherever possible. Currently, the cost of keeping someone in custody is around £800 plus per week in the UK. The word 'fun' derives from Gallows humor. How would you like to be out dinning out with the wife and daughter after a hard day at the airport and get asked and so, what have you been doing today at work dear? and just at that very moment when you’re about to tear off a piece of naan bread with those very same fingers that had only been hours before some where unmentionable? Therefore, I would have thought that those here would have realised that 'fun' is a form of displacement . This leads me to think, that if you come to the UK and your seen waddling about with nothing more than a bout of mild constipation and are so ill prepared as this – be afraid - be very afraid . An' least I forget – Welcome to the United Kingdom and enjoy your visit!--Aspro (talk) 18:27, 27 May 2012 (UTC)

I think you're the one who is missing point, Aspro. In your answer you linked to Balloon swallower (not balloon inserter) and then mentioned using KY jelly and gloves to probe people. Either your two thoughts were completely disjointed (and hence confused other people) or you were in fact implying that 20 odd feet of intestines could be checked out in that manner. 203.27.72.5 (talk) 22:20, 27 May 2012 (UTC) 203.27.72.5 (talk) 22:20, 27 May 2012 (UTC)

The word 'also' in my second sentence denotes that there is a way of detecting other methods of concealment. On WP ref pages one doesn’t expect replies to be a complete and full dissertation running to many thousands of words to cover ever instance but a short synopsis – which one hopes - answerers the OP query. Of cause this seasoned WP approach can invite nit-pickers whose only purpose of being, appears to be: not to add but distract from the OP's questions. Commons sense in most reader would realize the limits of a digital examination meant two different cases of concealment. Talking of nits – do you know that you can also get fumigated in-flight with out being informed? --Aspro (talk) 19:43, 28 May 2012 (UTC)

In most cases they detain the suspect until objects inside the body decide to leave naturally, it has been known to take weeks but border officers have patience. MilborneOne (talk) 17:49, 25 May 2012 (UTC)

And how can they know whom to detain? OsmanRF34 (talk) 17:57, 25 May 2012 (UTC)

Airline Flights offer free food. If you're not seen to pig-out in-flight (belly already full) you get detained. --Aspro (talk) 18:33, 25 May 2012 (UTC)

I can only assume this is some poor excuse for a joke :-/ SemanticMantis (talk) 18:42, 25 May 2012 (UTC)

No joke coming. Mules can not eat or drink during the whole trip (including ride to airport etc.) Flight attendants get asked to report any passenger who either does not eat or who has a little bag at his side into which the food served is dumped (when he thinks the FA is not looking). You think that the FA is being friendly when s/he or it as asking you if you have a few little presents for your nearest and dearest in that little bag that you hold so close? Think again. --Aspro (talk) 19:00, 27 May 2012 (UTC)

The joke is that most airlines no longer provide food as part of the cost, and if you want any, you have to pay extra, and please have exact change available. It's in the same fantastic tradition as the price of a meal on certain restaurant menus only covering the meat/fish, and if you want any vegetables or salad or bread, you have to order them separately and pay extra. Airlines also charge for choosing the option of using a credit card to pay for the flight, when in most cases there isn't any alternative, and even if there were, it's inconvenient so most people wouldn't use it anyway. What next? Cinemas will be saying your $13 now only covers the previews and you'll have to pay extra to see the film you've come to see? -- ♬ Jack of Oz ♬ ^{[your turn]} 21:06, 25 May 2012 (UTC)

Getting a bit off topic here, but it must be said in all fairness to airline companies that the last time I was offered a free meal on a flight I paid the equivalent of 600€ for a flight from Munich to Athens. These days, the same flight costs less than 100€ - I could maybe dream up a meal that would be worth paying an extra 500€, but Olympic Airways plastic food wasn't in that category -- Ferkelparade π 00:15, 26 May 2012 (UTC)

Detector dogs can smell the contraband even if it's inside a person. 203.27.72.5 (talk) 20:53, 25 May 2012 (UTC)

Citation needed. Alansplodge (talk) 21:08, 26 May 2012 (UTC)

They usually give entrants the option to wait until they've had some specified number of bowel movements that they monitor (imagine applying to that job), or they offer the person an x-ray. Shadowjams (talk) 21:03, 25 May 2012 (UTC)

From TV documentaries I've seen, they look out for people who appear very nervous. The carriers know that if one of the bags bursts inside you, it's "game over". There are other clues - the country where the flight originated, people travelling alone, maybe with little luggage and/or no convincing story about the purpose of their journey. This BBC report says: "Passengers who are suspected of swallowing it (cocaine) are scanned using a full body X-ray machine at the customs terminal. The machine can then detect if the person's stomach contains the small packages." Another report says; "In December, a British man and woman arrived in Britain from Amsterdam after swallowing and stuffing about 500g of heroin. The woman required surgery to remove the drugs after eight days." Alansplodge (talk) 21:07, 25 May 2012 (UTC)

A UK Border Agency report: "Man jailed after swallowing cocaine" says; "Martins Ndubuisi Onkonkwo, aged 36, arrived at Birmingham airport on 18 May 2011 on a flight from Cameroon via Zurich. He was stopped and questioned by officers who suspected that he was smuggling drugs. He was examined using a high-tech internal body scanner which revealed several packages inside his stomach. He was then taken to Solihull hospital where an x-ray confirmed that many packages had been swallowed. Onkonkwo was then taken into custody at Manchester airport where nature was allowed to take its course. He eventually passed 55 pellets weighing 550 grams." Another African man in this report was detained after "officers became suspicious of his reasons for travel, and (he) became nervous when it was suggested that he had swallowed packages." Alansplodge (talk) 21:11, 25 May 2012 (UTC)

Me again. A British newspaper article describes a drug "mule" being detained after his "itinerary has set alarm bells ringing because of his circuitous, expensive route from Venezuela to London. Starting in Caracas, the man travelled to Trinidad’s Port of Spain and on to London, and he was then scheduled to continue to Amsterdam. His ‘holiday’ was supposed to last all of four days. ‘His route is highly unusual and suspicious...’" Alansplodge (talk) 21:30, 25 May 2012 (UTC)

My belief from watching shows like Border Security and Border Patrol is similar to Alansplodge. They rely significantly on intelligence and profiling. Travelling alone or with similar suspicious passengers, concealing details (like people you know) or otherwise being evasive, angry or vague (possibly to ordinary questions), not keeping a consistent story over time, travelling with people you don't seem to really know (they may seperate you and see if your stories are consistent), age, nervousness, coming from or visiting drug supply hotspots (or other suspicious itineraries/travel patterns), buying ticket with cash very recently (and perhaps similarly acquiring passports very recently), low incomes with odd explainations on how they can afford an expensive holiday (even more so if they only intending to stay for a very short time), not knowing anything about the place they are intending to visit, insufficient luggage for the intended stay time, etc. Sometimes they get intel on possible smuggling attempts or receive info from the flightcrew of suspicious passengers. During searching they also take swabs which may pick up drug traces which the passengers could have transferred either from the environment or if they were on the condoms or whatever. Many of these are also possible signs of other things of concern like people who intend to work illegally (also other things like not having enough money to support themselves and bringing CVs). These may single people out for attentions which will either stop or go on depending on whether you continue to raise redflags or satisfy them, or they may also put you in the the category where you're more likely to be subject to a full check regardless. (I believe I've been subject to both in a fashion.)

It's worth considering even for external body concealments while there's a likely additional sign of bulk or awkward clothing and greater chance they will be picked up by a detector dog, they are unlikely to rely on these alone. (Similar to with security before you board, there is a move to fullbody scanners by customs which if done on everyone may make such concealments difficult, but this is new.) Similarly with luggage concealments where there's also X-rays, many customs don't X-ray every piece of luggage. In other words, even in these cases they often have the same starting point, it's just easier to detect later. Note that at least I think in NZ, and possibly Australia, I believe you had/have? the same right to refuse a patdown or strip search by customs to look fo external concealments as you did a X-ray to look for internal concealments. They would need to bring their reasons for review [5] although I presume reviewers are more willing to allow a patdown then an internal Xray.

Nil Einne (talk) 10:19, 26 May 2012 (UTC)

Just an observation: we only get to find out about the ones who got caught. Noone (apart from the crims) ever finds out about successful mules. Robinh (talk) 01:51, 29 May 2012 (UTC)