A new technology that spots tooth decay almost as soon as it's begun promises to reduce the need for drilling and filling. Drilling is one of the top dental phobias and puts thousands of people off visiting their dentist every year.
The new technology, which may be available in dental surgeries in five years from now, is based on Raman spectroscopy most commonly used to distinguish between different chemicals by identifying each molecule's unique fingerprint. It detects decay simply and painlessly by pointing a tiny optical fibre at the tooth to check on its health.
A preliminary study at King's College London, where the technique is being developed, found that chemical changes in the tooth could be detected by analysing how light is scattered when a laser is fired at the tooth. Researchers were able to tell healthy teeth from carious teeth because bacteria, responsible for the decay, scatter light in a different way to healthy teeth.
Science & Technology
More than 75 percent of the bank Web sites surveyed in a University of Michigan study had at least one design flaw that could make customers vulnerable to cyber thieves after their money or even their identity.
Atul Prakash, a professor in the Department of Electrical Engineering and Computer Science and doctoral students Laura Falk and Kevin Borders examined the Web sites of 214 financial institutions in 2006. They will present the findings for the first time at the Symposium on Usable Privacy and Security meeting at Carnegie Mellon University July 25.
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| ©iStockphoto/Angel Herrero De Frutos |
Atul Prakash, a professor in the Department of Electrical Engineering and Computer Science and doctoral students Laura Falk and Kevin Borders examined the Web sites of 214 financial institutions in 2006. They will present the findings for the first time at the Symposium on Usable Privacy and Security meeting at Carnegie Mellon University July 25.
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| ©Unknown |
"The time to look is during the dark hours before dawn on Tuesday, August 12th," says Bill Cooke of NASA's Meteoroid Environment Office at the Marshall Space Flight Center. "There should be plenty of meteors--perhaps one or two every minute."
The source of the shower is Comet Swift-Tuttle. Although the comet is far away, currently located beyond the orbit of Uranus, a trail of debris from the comet stretches all the way back to Earth. Crossing the trail in August, Earth will be pelted by specks of comet dust hitting the atmosphere at 132,000 mph. At that speed, even a flimsy speck of dust makes a vivid streak of light when it disintegrates--a meteor! Because, Swift-Tuttle's meteors streak out of the constellation Perseus, they are called "Perseids."
For millennia, humans and viruses have been locked in an evolutionary back-and-forth -- one changes to outsmart the other, prompting the second to change and outsmart the first. With retroviruses, which work by inserting themselves into their host's DNA, the evidence remains in our genes.
Last year, researchers at Rockefeller University and the Aaron Diamond AIDS Research Center brought an ancient retrovirus back to life and showed it could reproduce and infect human cells. Now, the same scientists have looked at the human side of the story and found evidence that our ancestors fought back against that virus with a defense mechanism our bodies still use today.
"This is the first time that we've been able to take an ancient retrovirus and analyze how it interacts with host defense mechanisms in the laboratory in the present day," says Paul Bieniasz, who is an associate professor and head of the Laboratory of Retrovirology at Rockefeller and a scientist at the Aaron Diamond AIDS Research Center. Bieniasz and graduate student Youngnam Lee took their resurrected virus, called HERV-K, tested its strength against molecules involved in human antiviral defense.
Last year, researchers at Rockefeller University and the Aaron Diamond AIDS Research Center brought an ancient retrovirus back to life and showed it could reproduce and infect human cells. Now, the same scientists have looked at the human side of the story and found evidence that our ancestors fought back against that virus with a defense mechanism our bodies still use today.
"This is the first time that we've been able to take an ancient retrovirus and analyze how it interacts with host defense mechanisms in the laboratory in the present day," says Paul Bieniasz, who is an associate professor and head of the Laboratory of Retrovirology at Rockefeller and a scientist at the Aaron Diamond AIDS Research Center. Bieniasz and graduate student Youngnam Lee took their resurrected virus, called HERV-K, tested its strength against molecules involved in human antiviral defense.
Beijing - Thousands of ancient artifacts and wooden poles more than 3,000 years old have been unearthed in China's southern Yunnan province, possibly the world's largest site of a Neolithic community, local media reported on Tuesday.
The poles, found standing 4.6 meters underground, were used as part of building structures for an ancient community that may have covered an area of 4 square km, the China Daily reported, citing Min Rui, a researcher at Yunnan Archaeological Institute, who is leading the excavation team.
The site could be older than the Hemudu community in Yuyao, in Zhejiang province, which is among the most famous in China and is believed to be the birthplace of society around the Yangtze River.
An area of 1,350 sq m has already been uncovered and excavation is ongoing.
"I was shocked when I first saw the site. I have never seen such a big and orderly one," Yan Wenming, history professor at Peking University, was quoted as saying.
The poles, found standing 4.6 meters underground, were used as part of building structures for an ancient community that may have covered an area of 4 square km, the China Daily reported, citing Min Rui, a researcher at Yunnan Archaeological Institute, who is leading the excavation team.
The site could be older than the Hemudu community in Yuyao, in Zhejiang province, which is among the most famous in China and is believed to be the birthplace of society around the Yangtze River.
An area of 1,350 sq m has already been uncovered and excavation is ongoing.
"I was shocked when I first saw the site. I have never seen such a big and orderly one," Yan Wenming, history professor at Peking University, was quoted as saying.
A new fossil discovery- the first of its kind from the whole of the Antarctic continent- provides scientists with new evidence to support the theory that the polar region was once much warmer.
Scientists made a new fossil discovery in the Dry Valleys of the East Antarctic region. The fossils (ostracods) come from an ancient lake - 14 million years old - and are exceptionally well preserved, with all of their soft anatomy in 3-dimensions.
The discovery by an international team of scientists is published in Proceedings of the Royal Society B. It involved researchers from the University of Leicester, North Dakota State University, the British Geological Survey, Queen Mary University of London, and Boston University.
Scientists made a new fossil discovery in the Dry Valleys of the East Antarctic region. The fossils (ostracods) come from an ancient lake - 14 million years old - and are exceptionally well preserved, with all of their soft anatomy in 3-dimensions.
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| ©Mark Williams, University of Leicester |
| Figure of the fossil ostracod from the Dry Valleys. The specimen is less than 1 mm long, but preserves an array of soft tissues including legs and mouth parts. The head end is to the right. |
The discovery by an international team of scientists is published in Proceedings of the Royal Society B. It involved researchers from the University of Leicester, North Dakota State University, the British Geological Survey, Queen Mary University of London, and Boston University.
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| ©NASA/JPL |
| Satellites passed over the Indian Ocean tsunami of December 2004. Two of those satellites--Jason 1 and Topex/Poseidon--were equipped with altimeters that for the first time measured the height of a tsunami in the open ocean. |
For humans in the path of destructive hurricanes and tsunamis, an accurate warning of the pending event is critical for damage control and survival. Such warnings, however, require a solid base of scientific observations, and a new satellite is ready for the job.
The Ocean Surface Topography Mission (OSTM)/Jason 2 adds to the number of eyes in the sky measuring sea surface and wave heights across Earth's oceans. The increased coverage will help researchers improve current models for practical use in predicting hurricane intensity, while providing valuable data that can be used to improve tsunami warning models.
Indiana Jones's next adventure may well be in front of a computer if Hollywood scriptwriters decide to embrace a new approach to archaeological research in war-torn zones.
David Thomas, a Ph.D. student in La Trobe University's archaeological program in Melbourne, has used Google Earth to safely uncover historic sites in a remote part of war-torn Afghanistan.
Using the free Internet resource, Thomas found up to 450 possible archaeological sites in Registan, which borders Helmand and Kandahar provinces in southern Afghanistan. The decision to use Google Earth was "partly born out of adversity", Thomas said, when a planned field trip was cancelled because of security concerns.
The region has been made inaccessible because of the ongoing military conflict between western and Afghan government forces and the former Taliban government.
David Thomas, a Ph.D. student in La Trobe University's archaeological program in Melbourne, has used Google Earth to safely uncover historic sites in a remote part of war-torn Afghanistan.
Using the free Internet resource, Thomas found up to 450 possible archaeological sites in Registan, which borders Helmand and Kandahar provinces in southern Afghanistan. The decision to use Google Earth was "partly born out of adversity", Thomas said, when a planned field trip was cancelled because of security concerns.
The region has been made inaccessible because of the ongoing military conflict between western and Afghan government forces and the former Taliban government.
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| ©Google Earth |
| Using the free Internet resource, Google Earth, a scholar found up to 450 possible archaeological sites in Registan, which borders Helmand and Kandahar provinces in southern Afghanistan. Shwn is the citadel of Bust. Bust was the tenth to twelfth century Ghaznavid dynasty's winter capital that stretches along the Helmand River. |
Bureaucrats at the American Physical Society (APS) have issued a curious warning to their members about an article in one of their own publications. Don't read this, they say - we don't agree with it. But what is it about the piece that is so terrible, that like Medusa, it could make men go blind?
Carbon isotopes trapped for thousands of years in coral skeletons could establish the long-term frequency of major earthquakes in southeast Asia and the South Pacific, and perhaps enable these events to be forecast.
Geoscientists have used corals before to look at earthquake history, by studying the terraced growth patterns that result. A major quake can push up an entire region, thrusting parts of a reef above the low-tide level, killing the exposed coral polyps. The rest of the coral continues to grow, producing a 'hat-brim' pattern that can indicate elevation changes as small as a few centimetres. This phenomenon has allowed scientists to date many earthquakes, including major ones in 1797 and 1833 off Sumatra, Indonesia. But the pattern erodes over time, so it can only be used to identify quakes that occurred within the past few hundred years.
Geoscientists have used corals before to look at earthquake history, by studying the terraced growth patterns that result. A major quake can push up an entire region, thrusting parts of a reef above the low-tide level, killing the exposed coral polyps. The rest of the coral continues to grow, producing a 'hat-brim' pattern that can indicate elevation changes as small as a few centimetres. This phenomenon has allowed scientists to date many earthquakes, including major ones in 1797 and 1833 off Sumatra, Indonesia. But the pattern erodes over time, so it can only be used to identify quakes that occurred within the past few hundred years.
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| ©Soc./EPA/Corbis |
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