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  • Human hands emit light

    Human hands glow, but fingernails release the most light, according to a recent study that found all parts of the hand emit detectable levels of light. The findings support prior research that suggested most living things, including plants, release light. Since disease and illness appear to affect the strength and pattern of the glow, the discovery might lead to less-invasive ways of diagnosing patients. Mitsuo Hiramatsu, a scientist at the Central Research Laboratory at Hamamatsu Photonics in Japan, who led the research, told Discovery News that the hands are not the only parts of the body that shine light by releasing photons, or tiny, energized increments of light. "Not only the hands, but also the forehead and bottoms of our feet emit photons," Hiramatsu said, and added that in terms of hands "the presence of photons means that our hands are producing light all of the time." The light is invisible to the naked eye, so Hiramatsu and his team used a powerful photon counter to "see"it. The detector found that fingernails release 60 photons, fingers release 40 and the palms are the dimmest of all, with 20 photons measured.

    The findings are published in the current Journal of Photochemistry and Photobiology B: Biology. Hiramatsu is not certain why fingernails light up more than the other parts of the hand, but he said, "It may be because of the optical window property of fingernails," meaning that the fingernail works somewhat like a prism to scatter light. To find out what might be creating the light in the first place, he and colleague Kimitsugu Nakamura had test subjects hold plastic bottles full of hot or cold water before their hand photons were measured. The researchers also pumped nitrogen or oxygen gas into the dark box where the individuals placed their hands as they were being analyzed.

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    • Was Robin Hood ever in Nottingham ?

      Robin Hood was really a Welsh freedom fighter who never even set foot in Nottingham let alone Sherwood Forest, a historian has claimed. The medieval outlaw - said to have robbed from the rich to give to the poor - never once met Maid Marian nor the Sheriff of Nottingham, according to Stephen Lawhead. The American blows apart the widely accepted version of the legend in his new book, Hood, arguing that Robin Hood was really a hardened Guerrilla based in the Valleys. But tourism chiefs in Nottingham have rubbished the theory, warning: "Hands off our Robin!" Lawhead, 56, believes the folk hero and his band of merry men would have carried out their thieving in the Marsh, a primeval forest in Wales in the 11th century, more than a hundred years before the English Robin Hood. He claims Robin would not have been able to hide out in Sherwood Forest because it would have been too small and well chartered. Robin would, he said, be able to remain undetected in the vast and unknown forests of the March.

      The sheltered woodlands would have provided him with the perfect base to launch lightening attacks on invading Norman armies. In his book, Lawhead, still tells of a wronged nobleman turned heroic outlaw but names him as Bran ap Brychan instead of the more recognised Robin of Loxley. Bran is a spoiled and selfish prince who becomes the rightful heir to the kingdom of Elfael after his father is killed by the Normans. He quickly becomes a marked man and makes plans to escape his kingdom and his people, until he is almost killed by the forces of Count Falkes de Braose, who took possession of the kingdom.

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        • Antimatter discovery could alter physics

          The discovery that a bizarre particle travels between the real world of matter and the spooky realm of antimatter 3 trillion times a second may open the door to a new era of physics, Fermilab researchers announced Monday. The incredibly rapid commuting rate of the B sub s meson particle had been predicted by the Standard Model, the successful but incomplete theory aimed at explaining how matter and energy interact to form the visible universe. After 20 years of trying, scientists have now confirmed the rate, providing strong evidence for the theory.The monumentally precise technology developed to measure the meson's back and forth dashes also may open the way to discovering a new family of fundamental particles and possibly a set of new forces that could be harnessed for technological applications, physicists suggested.The discovery comes at a time when the future of Fermilab, located near Batavia, Ill., is in doubt. Its huge 4-mile circular Tevatron particle accelerator may be forced to close by 2010 if Congress does not approve construction at Fermilab of a multibillion-dollar, 18-mile-long International Linear Collider.Without the collider, the United States would lose its lead position in high-energy physics discoveries to Europe, where a new accelerator seven times more powerful than the Tevatron is to start up within two years at a site on the Swiss-French border.The meson finding shows that Fermilab, which began operations in 1967, is still capable of making breakthrough discoveries. Scientists there discovered two of the most fundamental particles, the bottom quark in 1977 and in 1995 the top quark, one of the constituent particles of protons, which form the nuclei of atoms.

          Raymond Orbach, undersecretary for science with the U.S. Department of Energy, called the breakthrough "a triumph for Fermilab.""This remarkable tour de force details with exquisite precision how the antiworld is tied to our everyday realm," he wrote in a statement. "It is a beautiful example of how, using increasingly sophisticated analysis, one can extract discovery from data from which much less was expected."For all that scientists have learned about the universe it is still a mysterious place. Immediately after the Big Bang some 13 billion years ago equal amounts of matter and antimatter formed. Much of it quickly acted to annihilate the other, but for little-understood reasons a bit more matter than antimatter survived, providing the universe with the planets, stars and galaxies visible today.

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          • UFOs across Michigan's Upper Peninsula

            At least 60 sightings of unidentified flying objects (UFOs) have been reported across Michigan's Upper Peninsula since 1968, but for some time now the region has needed a field investigator certified by the international Mutual UFO Network (MUFON). The Michigan chapter of MUFON recently appointed the UP's only certified field investigator, Lisa A. Shiel, as the State Section Director for the UP as well as the Chief Investigator for the state of Michigan.Documented UFO sightings in the UP include a huge, slow-moving triangle with edge lights in Dickinson County (May 2006), a disc that hovered for two minutes over Boston Location (May 199 and three lights (one white, two green) that illuminated the night like daylight near Bessemer (August 1987). Whatever they might have been, unusual objects have certainly been observed in the skies over the Upper Peninsula.Lisa Shiel, author of several books published by Lake Linden publisher Slipdown Mountain Publications LLC, has discussed her research and theories in TV, radio and newspaper interviews.

            Her new assignment as Michigan-MUFON Chief Investigator means she will coordinate the investigations of UFO sightings across the state and lead her own investigations into those reported in the UP. In her new positions, Shiel quickly assigned 27 sighting reports (from Charlevoix to Adrian) to Michigan-MUFON field investigators and personally began five investigations into reported UP sightings in Chippewa, Delta, Dickinson, Luce and Menominee Counties.

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            • Mystery surrounds death of arctic divers

              Five hundred miles north of Alaska, a group of shipmates from the Coast Guard cutter Healy tossed a football on the blue-and-white, diamond-hard Arctic ice. Others snapped panoramic photos and took walks during the two-hour break, stretching their legs after a month aboard the 420-foot icebreaker.Lt. Jessica Hill and Boatswain's Mate Steven Duque seized the chance for a training dive and slipped into a patch of open water near the Healy's bow. A team held ropes attached to the divers, lest they become disoriented under the ice. Several research scientists watched from the deck.But no one knows what happened on the other end of those ropes on that cold, brilliant summer day - except that both divers died.The Coast Guard has started two investigations, relieved the Healy's captain, pulled all diving equipment off the ship and suspended all polar diving. But nothing has been said about what might have killed Hill, 31, and Duque, 22, on Aug. 17, or when the investigations will conclude."We can get no word whatsoever, and that's tough," Hill's father, William Hill Jr., said.

              "We can't even get the death certificates."The pair had been underwater for about 10 minutes, estimated Harm Van Avendonk, a University of Texas geophysics researcher, and something appeared to be wrong."I saw people from the bow looking intently down on the ice, and I sensed immediately that they didn't look relaxed," he said. "It was taking a long time for the divers to reappear."In a blur, the crew's training took over, several witnesses said.

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              • Mummified dogs uncovered in Peru

                Archaeologists in Peru have uncovered the mummified remains of more than 40 dogs buried with blankets and food alongside their human masters. The discovery was made during the excavation of two of the ancient Chiribaya people who lived in southern Peru between AD 900 and AD 1350. Experts say the dogs' treatment in death indicated the belief that the animals had an afterlife. Such a status for pets has only previously been seen in ancient Egypt. Hundreds of years before the European conquest of South America, the Chiribaya civilisation valued its dogs so highly that when one died, it was buried alongside family members.The dogs, which have been called Chiribaya shepherds for their llama-herding abilities, were not sacrificed as in other ancient cultures, but buried with blankets and food in human cemeteries. Biological archaeologists have unearthed the remains of more than 40 dogs which were naturally mummified in the desert sand of Peru's southern Ilo Valley.

                Now they have teamed up with Peru's Kennel Club to try to establish if the dogs represent a new distinct breed indigenous to South America. The country is full of breeds which arrived in the last few centuries, but they believe some dogs living today in southern Peru share the characteristics of their ancestors.

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                • Travelers to Africa, Asia returning with new virus

                  ATLANTA - Travelers to parts of Africa and Asia are returning with a new mosquito-borne virus and the U.S. Centers for Disease Control and Prevention warned on Thursday it could become entrenched in new areas.

                  Some people returning to Europe, the United States, Canada, Martinique and French Guyana reported cases of Chikungunya fever (CHIKV) in 2006 and large outbreaks have been reported in Indian Ocean islands and in India, according to the report.

                  The virus first emerged in Tanzania in 1953 and, though no deaths have been recorded, it can cause a debilitating illness whose symptoms include fever, headache, fatigue, nausea, vomiting, muscle and joint pain and rash. No specific drug therapy or vaccine exists to treat it.

                  "Some risk exists that CHIKV might be introduced into previously nonendemic areas by travelers with viremia, leading to local transmission of the virus," the report said.

                  It singled out tropical or subtropical areas of the U.S. including the Gulf Coast, Hawaii and the Virgin Islands as particularly at risk.

                  "Suspected cases should be reported promptly to local and state public health officials and to CDC," it said, adding that in the week after the virus had been detected it was essential that patients be screened from contact with mosquitoes.

                  "Clinicians should be alert for additional cases among travelers and public health officials should be alert to evidence of local transmission ... through infection of local mosquitoes by a person with viremia," the CDC report said.

                  The Atlanta-based CDC said it had detected 12 cases since the start of 2005 from travelers returning to the United States from areas where the virus was present.

                  In one case a man from Minnesota returned from a three-month trip to Somalia and Kenya in May 2005 and hours after arrival began to suffer from headache, malaise and joint pains, mainly in his shoulder and knee.

                  CDC diagnosed CHIKV infection, treated him and he recovered within weeks.

                  In another case, a physician in Maryland diagnosed CHIKV fever in a woman who had visited Reunion in the Indian Ocean in October 2005 and stayed for several months during which there was an outbreak on the island.

                  In the two years to May 2006 around 300,000 suspected CHIKV fever cases were reported on Indian Ocean islands, mainly on Reunion, a French overseas department, but also in Mombasa, Kenya; Madagascar; Mauritius and the Comoros islands.

                  Most of the 340 imported CHIKV cases in Europe between January and May this year were in France, in part because Reunion is a popular destination for French tourists.

                  Around 180,000 suspected CHIKV fever cases were also detected in the Indian states of Andhra Pradesh, Karnataka, and Maharashtra since early this year, the report said.

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                    • Does the Loch Ness Monster exist ?

                      Start looking into the phenomenon of the Loch Ness Monster and you cannot help but stir up controversy. Nessie is one of the most iconic symbols of Scotland and every year thousands of tourists make the trip to the banks of Loch Ness. But the question of what is, or isn't, beneath the deep mysterious waters of the loch has given rise to feuds, rivalries, forgeries and even bombings. Even today, a simmering rivalry exists between the two monster museums of Drumnadrochit, one of which takes a sceptical view of the mystery, while the other is very much pro-Nessie. Years of hoaxes, pseudoscience and counterculture obsessives have made Nessie a dubious area for serious naturalists, while monster souvenirs are a byword for tourist tat. Yet, Nessie is one of our most enduring myths, with a history which stretches from St Columba to The Simpsons.

                      Whatever the real nature of the beast, she has become a much-loved symbol of the nation, instantly recognisable across the world. Stories involving St Columba, and early-history Pictish carvings found in the Highlands, include a strange beast with flippers and a beak. Folk tales speak of kelpies, mischievous water horses who lured children to their deaths, and early maps contain places marked Loch Na Beistie. The first written account of Nessie comes in St Adamnan's Life of St Columba in the seventh century, which tells of the saint rescuing a Pict from a monster in Loch Ness. Columba declared: "Thou shalt go no further, nor touch the man: go back with all speed." Some say Nessie has never attacked anyone since - others believe the story is a parable showing Christianity overpowering pagan belief in nature spirits.

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                            • Halathaye Mavad

                              كلاً مواد در جهان در شش حالت ظاهر مي شوند :

                              جامد، مايع، گاز، پلاسما، ماده چگال باس-اينشتين و حالت تازه كشف ‌شده: ماده چگال فرميوني.

                              مواد جامد در برابر تغيير شكل مقاومت مي‌كنند، آنها سخت و گاهي شكننده اند.

                              مايع‌ها به راحتي تغيير حالت مي دهندو به سختي متراكم مي‌گردند و شكل ظرف خود را مي‌گيرند.

                              گاز‌ها كم چگال‌تر اند و ساده‌تر متراكم مي‌شوند و نه‌تنها شكل ظرف محتويشان را مي‌گيرند، بلكه آن‌قدر منبسط مي‌شوند تا كاملا آن را پر كنند. در ترموديناميك بررسي قوانين گاز ها از گازهاي كامل استفاده مي شود . اين گازها معمولاً در شرايط استاندارد حالت گاز را به خود مي گيرند.
                              حالت چهارم ماده، پلاسما، شبيه گاز است و اما ذرات سازنده آن يون ها مي باشد. در جهان بيشتر مواد در حالت پلاسماهستند، مثل خورشيد و ساير ستارگان . پلاسما اغلب بسيار گرم است و مي‌توان آن را در ميدان‌هاي مغناطيسي به دام انداخت.

                              حالت پنجم با نام ماده چگال باس-اينشتين (Bose-Einstein condensate) كه در سال 1995 كشف شد، در اثر سرد شدن ذراتي به نام باسن‌ها (Bosons) تا دما‌هايي بسيار پايين پديد مي‌آيد. باسن‌هاي سرد در هم فرومي‌روند و ابر ذره‌اي كه رفتاري بيشتر شبيه يك موج دارد تا ذره‌اي معمولي شكل مي‌گيرد. ماده چگال باس-اينشتين شكننده‌است وسرعت نور در آن بسيار كم است .

                              ديبورا جين (Deborah Jin) از دانشگاه كلورادو كه گروهش در اواخر پاييز امسال ( 1382 ) موفق به كشف اين شكل تازه ماده شده‌است، مي‌گويد: وقتي شكل جديدي از ماده روبرو مي‌شويد بايد زماني را صرف شناخت ويژگي‌هايش كنيد. آنها اين ماده تازه را با سرد كردن ابري از پانصدهزار اتم پتاسيم - 40 تا دمايي كمتر از يك ميليونيم درجه بالاتر از صفر مطلق پديدآوردند. اين اتم‌ها در چنين دمايي بدون گران‌روي جريان مي‌يابند و اين نشانه ماده جديد بود. در دما‌هاي پايين‌تر چه اتفاقي مي‌افتد؟ هنوز نمي‌دانيم.

                              ماده چگال فرميوني بسيار شبيه ماده چگال باس-اينشتين (BEC) است. هر دو از فرورفتن اتم‌ها در دماهايي بسيار پايين ساخته‌مي‌شوند. اتم‌هاي BEC باسن اند و اتم‌هاي ماده چگال فرميوني، فرميون. باسن‌ها درهم فرومي‌روند، اما فرميون‌ها اينگونه نيستند. باسن‌ها اتم‌هايي هستند كه مي‌توانند در هم فرو روند. به طور كلي اگر تعداد (الكترون + پروتون + نوترون اتمي) عددي زوج باشد، آن اتم يك باسن است. مثلا اتم‌هاي سديم معمولي باسن ‌اند و مي‌توانند به حالت فاز چگال باس-اينشتين ادغام شوند. اما فرميون‌ها مطابق اصل طرد پائولي نمي‌توانند در يك واحد كوآنتومي در هم ادغام شوند. هر اتمي كه تعداد الكترون‌ها + پروتون‌ها + نوترون‌هايش عددي فرد باشد، مثل پتاسيم - 40 يك فرميون است. گروه جين براي مقابله با خواص ادغام‌ناپذيري فرميون‌ها از تأثير ميدان مغناطيسي بر آنها استفاده‌كردند.

                              ميدان مغناطيسي سبب مي‌شود اتم‌هاي تنهاي فرميون جفت شوند. قدرت اين پيوند را ميدان مغناطيسي تعيين مي‌كند. جفت‌هاي اتم‌هاي پتاسيم برخي از خواص فرميونيشان را حفظ مي‌كنند، ولي كمي شبيه باسن‌ها عمل خواهند‌كرد. يك جفت فرميون مي‌تواند در جفت ديگري ادغام شود - و جفت تازه در جفتي ديگر ...- تا سرانجام ماده چگال فرميوني شكل‌گيرد. در اثر اين پديده، گران‌روي (Viscosity) ماده به وجود آمده بايد بسيار كم باشد. جفت‌هاي فرميون مي‌توانند درهم فروروند و شبيه باسن‌ها عمل كنند. مشابه اين پديده را در ابررسانايي مي‌بينيم. در يك ابررسانا، جفت‌هاي الكترون (الكترون‌ها فرميون اند) مي‌توانند بدون هيچ مقاومتي جريان يابند. متأسفانه مطالعه و دسترسي به ابررسانا‌ها بسيار مشكل است. گرم‌ترين ابررساناي امروزي مي توانند در دماي (135- )درجه سانتيگيراد عمل مي‌كند و اين بزرگ‌ترين مشكل براي مطالعه و استفاده از آنهاست. قدرت جفت‌شدن شگفت‌انگيز در حالت جديد، دانشمندان را اميدوار كرده‌است كه بتوانند از يافته‌هاي خود درباره حالت تازه ماده، براي توليد ابررساناها در دماي اتاق استفاده ‌كنند.

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