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301.www.csa.com146000
302.www.oiseaux.net145000
303.www.esri.com143000
304.www.deakin.edu.au142000
305.www.cpc.ncep.noaa.gov142000
306.xroads.virginia.edu142000
307.www.gi-ev.de142000
308.volcano.und.nodak.edu141000
309.www.unu.edu141000
310.digitalarkivet.uib.no141000
311.www.nist.gov140000
312.hubblesite.org139000
313.www.spc.noaa.gov139000
314.www.rki.de139000
315.www.freetranslation.com138000
316.www.fnal.gov138000
317.www.flmnh.ufl.edu138000
318.stats.bls.gov137000
319.www.sintef.no137000
320.www.oeaw.ac.at137000
321.www.fis.unipr.it137000
322.www.cs.uni-magdeburg.de136000
323.‚¨¯—l‚ƃRƒ“ƒsƒ…[ƒ^...">star.gs136000
324.www.jlab.org135000
325.www.ids-mannheim.de135000
326.www.dokpro.uio.no134000
327.www.niehs.nih.gov133000
328.www.aps.org132000
329.www.gehealthcare.com132000
330.www.vde.com131000
331.www.buscagro.com131000
332.www.naturamediterraneo.com130000
333.www.wur.nl129000
334.www.astro.uio.no128000
335.www.imr.no128000
336.www.informatik.uni-tuebingen.de127000
337.www.iss.it127000
338.www.plos.org127000
339.www.dfg.de126000
340.www.cis.es126000
341.www.heavens-above.com125000
342.whale.wheelock.edu125000
343.www.ee.ethz.ch124000
344.www.msh-paris.fr124000
345.www.cesga.es124000
346.www.math.uu.se124000
347.www.extension.umn.edu123000
348.www.dsi.cnrs.fr123000
349.www.lifl.fr123000
350.herba.msu.ru122000
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321. www.fis.unipr.it

Rating: 137000 points*
*amount mentions of word 'www.fis.unipr.it' on the other websites

www.fis.unipr.it

Dipartimento di Fisica - Universita' degli studi di Parma

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Feds: Don't tip off miners on surprise inspections
By SAM HANANEL 2010-08-26T20:47:53ZWASHINGTON (AP) -- Some mine companies are tipping off their underground workers before federal officials make surprise inspections, an illegal practice that has become more prevalent since a West Virginia explosion killed 29 miners, the nation's top mine official said Thursday....
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Why do we eat chilli?
Chillies burn our tongues, make our eyes water and bring us out in a sweat. Jason Goldman looks at a peculiarly human form of masochismJason is a developmental psychologist and blogs at The Thoughtful AnimalDave's Red Hot. Mother Puckers. Green Bandit. Scorned Woman. Pain is Good. Blair's Death. No, they're not rock bands. These names represent just a small selection of the brands of hot sauce available at my local supermarket.Humans, apparently, enjoy torturing themselves. Spiciness, after all, is not a flavour, not like sweet or salty or sour. Spicy means pain. The sensation of spiciness is the result of the activation of pain receptors in the tongue. According to psychologist Paul Rozin of the University of Pennsylvania, about a third of the people around the world eat hot peppers every single day. Why? Because they "love the burn". At a symposium on gastro-psychology during this year's Association for Psychological Science convention, Rozin pointed out that humans are the only species – we know about – that specifically seek out what would otherwise be considered negative events.Healthy, sane humans do not stab themselves in the thighs, or bathe their eyes in lemon juice. So why do we so love to assault one of the most sensitive organs in the human body, the tongue, with what amounts to chemical warfare? Chillies are unique among foods that we should otherwise not enjoy. For example, humans also have natural aversions to the bitterness of coffee or the harshness of tobacco, but those substances have some addictive qualities, which might make them desirable. Capsaicin, the compound that provides the mouth-watering punch of chillies, does not seem to have any addictive qualities whatsoever. And yet the preference for capsaicin is almost universal; nearly every culture has incorporated it into their cuisine in some way, for milllennia.Rozin writes:"There are records suggesting use of chilli pepper dating back to 7000BC in Mesoamerica; they were domesticated some thousands of years after this. These fiery foods made their debut in the Old World when they were brought back by Columbus and other early explorers. In spite of their initial unpalatability, they became accepted as a basic part of the diet in many parts of the world: west and east Africa, India, south-east Asia, parts of China, Indonesia, Korea, and other smaller geographic regions, such as Hungary."Most young children, even from cultures known for their spicy recipes, are averse to capsaicin. So maybe, then, instead of actually liking the pain, we're merely desensitising ourselves: what used to be really painful is now just sort of painful.Since capsaicin is a member of the vanilloid family of molecules, it binds to a receptor on the tongue called the vanilloid receptor subtype 1. Upon binding to the VR1 receptor, the sensation produced by the capsaicin molecule is the same sensation that heat would cause, which explains capsaicin's burn. When scientists discovered that the VR1 receptor was a member of the larger family of TRP ion channels, the VR1 receptor was renamed TRPV1. TRP receptors are known to be sensitive to changes in temperature and are likely responsible for temperature sensation. When chilli peppers are the source of the capsaicin, there isn't any actual tissue damage; but because it binds to the TRPV1 receptor, the brain is tricked into believing that the tongue truly is on fire.In 1980, Rozin and a colleague, Deborah Schiller, reported a study in which they compared the pepper preferences of Mexicans and Americans. Mexicans generally eat chillies several times per day, while Americans only eat chillies a few times a week. If desensitisation could explain our preference for oral pain, then Mexicans should show higher tolerance for capsaicin than Americans, and Americans should more easily detect capsaicin, even in small amounts, than Mexicans.The data only weakly supported these predictions: the differences were seen, but were not statistically significant. Another prediction made by the desensitisation hypothesis is that individual tolerance should increase with exposure, and therefore with age. Rozin and Schiller found no correlation between age and tolerance though. Experiments conducted to try to induce a preference for capsaicin in rats, using traditional reinforcement techniques, proved futile.In the late 1970s, Frito-Lay tried to market a brand of corn chips in Mexico that had the flavour of chilli peppers, but without any capsaicin. As would be expected in a culture that actually enjoys the burn, the product was a failure. Likewise, bell peppers, which have some pepper flavour but no capsaicin, are not at all popular in Mexico.While most scientists still do not quite have a handle on the human preference for spicy foods, the best explanation comes from a mechanism called "hedonic reversal", or "benign masochism". Something happens, in millions of humans each year, which changes a negative evaluation into a positive evaluation, like flipping a light switch.Rozin writes: "If the oral receptors are sending the same message to the brain in the chilli liker and the chilli hater, then the chilli liker must have come to like the very same sensation that the chilli hater, the infant, and nonhuman animals find aversive. One gets to like the burn." Only humans seem to be able to derive pleasure from the negative sensation itself. Animals have been trained to endure self-harm, but only within the context of positive reinforcement.Perhaps we seek out the painful experience of snacking on chillies while consciously maintaining awareness that there is no real danger to ourselves. After all, people seem to enjoy – and actively seek out – many other sensations that are otherwise undesirable but are ostensibly safe: the sensation of falling provided by rollercoasters or skydiving, the feelings of fear and anxiety while watching horror movies, the physical pain experienced upon jumping into icy water, or even the feelings of sadness that come while watching a tear-jerker. Perhaps it is this cognitive mismatch itself that provides the thrill: like strapping into a rollercoaster or popping Hostel into your DVD player over and over again, the burn of capsaicin only seems to be threatening.Want a thrill? Go out and buy yourself a bottle of One Fuckin' Drop At A Time Hot Sauce. It comes with an eye-dropper for portion control. Benign masochism, indeed.Jason Goldman is a developmental psychologist and blogs at The Thoughtful AnimalFood sciencePsychologyFood & drinkNeuroscienceguardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds
guardian.co.uk
Scientists seek deodorant for smelly kiwis
Researchers are hoping to develop a deodorant for New Zealand's native birds to stop them falling prey to introduced predators.
abc.net.au
A Global Warming 'Work Party'
Climate campaigners organize thousands of events aimed at limiting warming.
feeds.nytimes.com
Sea ice melting as Arctic temperature rises
By RANDOLPH E. SCHMID 2010-10-21T18:56:03ZWASHINGTON (AP) -- The temperature is rising again in the Arctic, with the sea ice extent dropping to one of the lowest levels on record, climate scientists reported Thursday....
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