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November 19, 2006, 9:07 PM CT

Virtual Biopsies Of Internal Surfaces

Virtual Biopsies Of Internal Surfaces OFDI image of the stented coronary artery of a pig
A new optical imaging technique, developed at the Wellman Center for Photomedicine at Massachusetts General Hospital (MGH), can provide three-dimensional microscopic views of the inner surfaces of blood vessels and gastrointestinal organs. In their report in the journal Nature Medicine, receiving early online release today, the MGH-Wellman researchers describe using optical frequency-domain imaging (OFDI) to visualize broad areas of the esophagus and coronary arteries of living pigs. The technique is an advance over optical coherence tomography (OCT) another noninvasive MGH-developed technology that details much smaller areas and could be useful for identifying precancerous lesions and dangerous deposits of plaque in the coronary arteries.

"For diagnosing early-stage disease, the doctor has been basically looking for a needle in a haystack; so sampling only a few microscopic points of an organ, as we could with OCT, is clearly not sufficient," says Brett Bouma, PhD, of the MGH-Wellman Center, the report's senior author. "With OFDI, we can now perform microscopy throughout very large volumes of tissue without missing any locations".

While OCT can examine surfaces one point at a time, OFDI is able to look at over 1,000 points simultaneously by using a new type of laser developed at MGH-Wellman. Inside the fiberoptic catheter probe, a constantly rotating laser tip emits a light beam with an ever-changing wavelength. Measuring how each wavelength is reflected back, as the probe moves through the structure to be imaged, allows rapid acquisition of the data required to create the detailed microscopic images.........

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November 19, 2006, 9:02 PM CT

Which Wasps Are Bad Losers

Which Wasps Are Bad Losers Wasps fighting over larvae on which to lay their eggs release potent chemicals if they are defeated.
Wasps have more than just a sting in their tail according to new research published this week in the Proceedings of the Royal Society B, they also carry the insect version of pepper spray in their heads, which they can release when fighting other wasps. The research not only gives us a fascinating insight into insect behaviour but could also help us to use wasps to kill crop destroying pests.

For the first time scientists, funded by the Biotechnology and Biological Sciences Research Council (BBSRC), have recorded 'chemical exchanges' undetectable by the human nose which take place between females of a species of bethylid wasp - Goniozus legneri, when they fight over larvae on which they lay their eggs. Not only have they discovered that chemical exchanges take place, but also that it is always the losing wasp that releases the potent gas.

While the research was primarily aimed at improving the understanding of animal behaviour, lead researcher Dr Ian Hardy, from the University of Nottingham, explains that there is great potential for applied spin-offs: "Bethylid wasps kill the larvae of many insects that are pests of crops, such as almonds, coffee and coconut, ruining harvests and costing industry thousands of pounds. These wasps could be used as a cheap and effective biological control to kill the larvae, avoiding the use of expensive and polluting pesticides. But for successful biological control, we need a good knowledge of wasp behaviour, including how wasps from the same and different species interact. Understanding these patterns can inform us of the best combinations of species to release against a given crop pest."........

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November 16, 2006, 9:19 PM CT

Personality Traits And Heart Disease

Personality Traits And Heart Disease
Frequent bouts of depression, anxiety, hostility and anger are known to increase a person's risk for developing coronary heart disease, but a combination of these "negative" personality traits may put people at particularly serious risk, as per a research studyby scientists at Duke University Medical Center.

"The risk of developing coronary heart disease due to a combination of negative personality traits in people has never before been explored," said the study's senior investigator, Edward C. Suarez, Ph.D., an associate professor of psychiatry. "Eventhough each of the negative traits significantly predicted heart disease, having the combination of these traits was the most powerful predictor of heart disease".

Similar patterns have been reported with three traditional risk factors of heart disease -- high blood pressure, elevated cholesterol levels and excessive weight -- where each factor independently increases risk but their presence together predicts a greater risk of future heart disease, Suarez said.

The findings are published in an early online edition of the November/December 2006 issue of the journal Psychosomatic Medicine.

The research was funded by the National Institutes of Health.

The team analyzed data on 2,105 military veterans who served in the Vietnam War and took part in the U.S. Air Force Health Study, in which scientists tracked the health of participants for 20 years. None of the men enrolled had heart disease when the study began.........

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November 16, 2006, 8:37 PM CT

Relatives Of Protons And Neutrons

Relatives Of Protons And Neutrons
A team of scientists, including four at The Johns Hopkins University, has discovered two new subatomic particles, rare but important relatives of the familiar, commonplace proton and neutron.

Named "Sigma-sub-b" particles, the two exotic and incredibly quick to decompose particles are like rare jewels mined from mountains of data, said team leader Petar Maksimovic, assistant professor of physics and astronomy in the university's Krieger School of Arts and Sciences.

"These particles are members of what we call the 'baryonic' family, so-called for the Greek word 'barys,' which means heavy," Maksimovic said. "Baryons are particles that contain three quarks, which are the fundamental building blocks of matter".

The simplest baryons are the proton and neutron, which make up the nuclei of atoms of ordinary matter. "These newest members of that family are unstable and ephemeral, but they help us to understand the forces that bind quarks together into matter," Maksimovic said.

Containing the second-heaviest quark - called "the bottom quark" - the new particles are the heaviest baryons found yet: heavier even than a complete helium atom, which has two protons, though lighter than a lithium atom, which has three.

How rare is Sigma-sub-b? The team combed through a hundred trillion proton-antiproton collisions at the Tevatron, the world's most powerful particle accelerator, to find about 240 Sigma-sub-b candidates, Maksimovic said. The new particles are extremely short-lived, decaying within a tiny fraction of a second.........

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November 16, 2006, 7:00 PM CT

Satellite phones get a makeover

Satellite phones get a makeover
With Verizon Wireless and Sprint's release of the KRZR, life just gets sexier and sexier in the land of mobile phones, but what about the necessary-but-oh-so-utilitarian-looking land of satellite phones?

Effective immediately, satellite phones have joined the world of the beautiful. Globalstar, Inc., a leading provider of mobile satellite phones, has introduced the new GSP-1700 mobile satellite telephone.

The newly designed GSP-1700 telephone is nearly half the weight of the company's current satellite handset and close to 45 percent smaller. A new lithium-ion battery is designed to provide users with four hours of talk time and 36 hours of standby time. The GSP-1700's lightweight ergonomic design embodies the ruggedness of the current Globalstar phone while integrating convenience-oriented features such as a new five-mode color display and Bluetooth headset capability. The phone supports six operating languages and is available in three vibrant faceplate colors, using durable high-luster or metallic finishes. The GSP-1700 is being manufactured by QUALCOMM and incorporates a data solution and EV-DO network capability.........

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November 16, 2006, 4:53 AM CT

Grid computing 'Mappa mundi'

Grid computing 'Mappa mundi'
Visitors to Supercomputing '06 in Tampa, Florida this week will be the first to see a new interactive map that shows nine of the world's largest computing Grids. The map, developed by researchers from GridPP in the UK and the European particle physics laboratory, CERN, in Geneva, uses Google Earth to pinpoint Grid sites on six continents, showing more than 300 sites overall. Like the medieval 'mappa mundi', which showed what was known of the world at the time, this is one of the first attempts to show the whole scientific Grid world.

Laurence Field, who works at CERN for the Enabling Grids for E-sciencE project, has been leading work on the map. He explains, "Today there are a number of production Grids being used for science, several of which have a strong regional presence. Many of them are using different middleware, which can artificially limit scientific collaboration. The Grids shown on the map are all taking part in the Open Grid Forum's Grid Interoperation Now (GIN) group, which is trying to bridge the differences and enable seamless interoperation between the various infrastructures".

Gidon Moont from Imperial College London, developed the interface with Google Earth. It was then adapted by the GIN group, and will be shown on CERN's stand and the UK e-Science stand at Supercomputing.........

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November 16, 2006, 4:35 AM CT

Relativistic Pinball Machine

Relativistic Pinball Machine Spitzer Infrared Image of Cassiopeia A
New clues about the origins of cosmic rays, mysterious high-energy particles that bombard the Earth, have been revealed using NASA's Chandra X-ray Observatory. An extraordinarily detailed image of the remains of an exploded star provides crucial insight into the generation of cosmic rays.

For the first time, astronomers have mapped the rate of acceleration of cosmic ray electrons in a supernova remnant. The new map shows that the electrons are being accelerated at close to the theoretically maximum rate. This discovery provides compelling evidence that supernova remnants are key sites for energizing charged particles.

The map was created from an image of Cassiopeia A, a 325-year-old remnant produced by the explosive death of a massive star. The blue, wispy arcs in the image trace the expanding outer shock wave where the acceleration takes place. The other colors in the image show debris from the explosion that has been heated to millions of degrees.

"Researchers have theorized since the 1960s that cosmic rays must be created in the tangle of magnetic fields at the shock, but here we can see this happening directly," said Michael Stage of the University of Massachusetts, Amherst. "Explaining where cosmic rays come from helps us to understand other mysterious phenomena in the high-energy universe".........

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November 16, 2006, 4:22 AM CT

Neanderthal Genome Sequencing

Neanderthal Genome Sequencing Neanderthals are the closest hominid relatives of modern humans. The two species co-existed in Europe and western Asia as late as 30,000 years ago. (American Museum of Natural History)
The veil of mystery surrounding our extinct hominid cousins, the Neanderthals, has been at least partially lifted to reveal surprising results. Scientists with the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and the Joint Genome Institute (JGI) have sequenced genomic DNA from fossilized Neanderthal bones. Their results show that the genomes of modern humans and Neanderthals are at least 99.5-percent identical, but despite this genetic similarity, and despite the two species having cohabitated the same geographic region for thousands of years, there is no evidence of any significant crossbreeding between the two. Based on these early results, Homo sapiens and Homo neanderthalensis last shared a common ancestor approximately 700,000 years ago.

In a paper published in the November 17, 2006 issue of the journal Science, a team of researchers led by Edward Rubin, director of both JGI and Berkeley Lab's Genomics Division, reports the development of a "Neanderthal metagenomic library," which they used to characterize more than 65,000 DNA base pairs of Neanderthal origin. Their results not only provide new information about Neanderthals, but also point the way to a new strategy for studying aspects of Neanderthal biology that would never be evident from archaeological artifacts and fossils.........

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November 15, 2006, 9:45 PM CT

Listening To Gunshots May Save Lives

Listening To Gunshots May Save Lives Montana State University electrical engineering professor Rob Maher
From the crack of a supersonic bullet, Montana State University electrical engineering professor Rob Maher is exploring how sound can be used for everything from saving soldiers from snipers to saving wilderness from noise pollution.

This fall, Maher presented the results of two years of research into gunshots at the Institute of Electrical and Electronic Engineers (IEEE) Signal Processing Society's annual meeting in Jackson Hole, Wyo.

Because of its intense energy and distinctness, a gunshot is "the perfect signal" with which to explore the uses of sound, Maher said.

"It produces what engineers call the 'impulse response' of the sonic environment," Maher said. "If we can't make sense of how a gunshot behaves, then it's unlikely we can do much with more complicated, or lesser quality, sounds".

Maher initially explored two questions with gunshots: First, could the sound of a gunshot on a 911 recording be associated with a specific weapon? The question has intrigued prosecuting attorneys for decades. Second, could the sound of a gunshot be used to determine the location of a hidden sniper?

Through a search of prior studies and his own research, Maher found the "acoustical fingerprinting" of a gunshot from a 911 tape was impossible.........

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November 15, 2006, 4:43 AM CT

Nanoparticles To Target Brain Cancer

Nanoparticles To Target Brain Cancer
Tiny particles one-billionth of a meter in size can be loaded with high concentrations of drugs designed to kill brain cancer. What's more, these nanoparticles can be used to image and track tumors as well as destroy them, according to researchers at the University of Michigan Comprehensive Cancer Center.

Researchers incorporated a drug called Photofrin along with iron oxide into nanoparticles that would target cancerous brain tumors. Photofrin is a type of photodynamic therapy, in which the drug is drawn through the blood stream to tumor cells; a special type of laser light activates the drug to attack the tumor. Iron oxide is a contrast agent used to enhance magnetic resonance imaging, or MRI.

"Photofrin goes into tumor blood vessels and collapses the vasculature, which then starves the tumor of the blood flow needed to survive. The problem with free photofrin therapy is that it can cause damage to healthy tissue. In our study, the nanoparticle becomes a vehicle to deliver the drug directly to the tumor," says study author Brian Ross, Ph.D., professor of radiology at the U-M Medical School and co-director of Molecular Imaging at the U-M Comprehensive Cancer Center.

Photofrin has been used to treat several types of cancer, including esophageal, bladder and skin cancers. It works by traveling through blood vessels until it reaches the vessels supplying blood to the tumor. When activated by light, the Photofrin collapses these blood vessels, starving the tumor of the blood it needs to survive.........

Posted by: John      Permalink         Source


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