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New Technology For Lung Cancer Detection
Spiral Computerized axial tomography scan is a technique that is capable of detecting lung tumors early. In this type of Computerized axial tomography scan, the doctor obtains about 500 separate slice images of the chest with very high resolution. This would enable the doctor to find small lung tumors, before it may have spread to other organs, much like a mammogram in breast cancer. The problem with spiral Computerized axial tomography scan is that, it takes for ever to study the 500 or so slice that the machine produces for one person. Large-scale screening using this technique becomes practically impossible or at least very difficult because of the enormous amount of work involved. Computer-aided detection (CAD), can theoretically replace much of manpower with the computer technology. The computer-aided system that is available so far has not been very sensitive to do the job without errors, so a large number of false positive results occur with CAD......... Posted by: Kevin Permalink January 20, 2006, 6:40 AM CT Sensors for Environmental Observatories
"In situ," or in place, sensors are producing a revolution in our understanding of the environment, as per the new National Science Foundation (NSF) report, Sensors for Environmental Observatories. Sensors, the report states, will enable a deeper and broader understanding of Earth's environment. Better-informed public policies that address the interactions between human society and the natural environment will be the result. Environmental scientists, with the support of NSF and other agencies, have in recent years designed and begun to implement several new environmental observing systems, including EarthScope, the National Ecological Observatory Network (NEON), the Ocean Observatories Initiative (OOI), and others. "These efforts will enable much-needed longer-term sensing of the environment," said Margaret Leinen, NSF assistant director for geosciences. "However, there are significant limitations to current sensor technology and the networks that collect data from them". To track changing conditions in deserts, forests, oceans or the atmosphere, environmental sensors must, like the postman, deliver information through snow, sleet, rain, and dark of night......... Posted by: Tyler Permalink January 20, 2006, 1:08 AM CT New Computer Technologies Based On Magnetic Spin
A new discovery by this group opens a path to new computer technologies and related devices, and could drive entire industries into the future, the scientists say. The scientists learned that swirling spin structures called magnetic vortices, when trapped within lithographically patterned ferromagnetic structures, behave in novel ways. In a nickel-iron alloy, the two vortices swirl in opposite directions, one clockwise and the other counterclockwise. However, the scientists discovered that the magnetic polarity of the central core of the vortices, like the eye of a hurricane, controlled the time-evolution of the magnetic properties, not the swirling direction. The material being studied is about one micron in size, and the area of the vortex core is about 10 nanometers in size. For comparison, the period at the end of this sentence is about 100 microns or 100,000 nanometers in diameter. Group leader Sam Bader, an Argonne scientist for more than 30 years, explained that the work could lead to the next generation of electronic devices. "When the first computer hard disk was introduced 50 years ago, it mandatory a rather large size to store each bit of digital information. On today's computer disks, the corresponding size is about one-50-millionth of that needed in the original disks. We are now moving well into the nanoscale range, and nanomagnetism is one of the real drivers of the nanotechnology field"......... Posted by: Kevin Permalink January 20, 2006, 1:04 AM CT Device For More Accurate Injections
In response, a team of Georgia Institute of Technology scientists is developing an inexpensive, handheld device that uses Doppler ultrasound technology to find veins quickly. "Depth and angle are the critical issues for vessel detection," says project leader Michael Gray, a research engineer at the Electro-Optical (EOSL) Systems Laboratory within the Georgia Tech Research Institute (GTRI). "Even if you locate a vein at the skin's surface, it's still easy to miss when you try to insert a needle into the tissue below." The Doppler effect is a phenomenon that occurs when electromagnetic and sound waves interact with a moving object, altering wavelengths and frequency. For example, a police radar gun sends microwave signals to a moving car, and when signals bounce back, the change in their frequency provides a measurement used to determine the vehicle's speed. Doppler ultrasound is similar, except that acoustical waves are transmitted. Compared to static skin and tissue, blood is a moving substance, so ultrasonic waves reflected from blood vessels have different characteristics than transmitted ones, providing critical 3-D information about a vein's location......... Posted by: Kevin Permalink January 18, 2006, 7:59 PM CT Engineer, Dentist, And Veterinarian Building Bone
If two Virginia Tech researchers, collaborating with the American Dental Association (ADA), are able to successfully construct a tissue engineered composite material for oral reconstructions, these dismal statistics might yield a better outcome. The repair of the diseased tissue in these cancers often requires reconstruction of the bone, and Brian Love, professor of materials science and engineering in the College of Engineering at Virginia Tech and principal investigator on a National Institutes for Health (NIH) grant, believes "substantially better clinical outcomes for all oral constructions could result if a more viable scaffold material were used that was capable of faster and higher quality bone formation". Love and the team are looking at amorphous calcium phosphates (ACPs) as inorganic host materials in the rebuilding of tissue. ACPs, in the presence of cells that make bone (called osteoblasts), are believed to "more readily" provide the host material for new bone formation in tissue engineering than other choices, Love explains......... Posted by: Kevin Permalink January 16, 2006, 10:44 PM CT Protein Nanosprings
The team's findings were published in an advanced online publication of Nature on Jan. 15, 2006. The finding that the protein components, called "ankyrin repeats," exhibit such unprecedented elastic properties could lead to a new understanding of how organisms, including humans, sense and respond to physical forces at the cellular level, the scientists said. The nanometer-sized springs are also ideal candidates for building biologically-inspired springy nanostructures and nanomaterials with an inherent ability to self-repair, they reported. A nanometer is one billionth of a meter. "Whereas other known proteins can act like floppy springs, ankyrin molecules behave more like steel," said Piotr Marszalek, professor of mechanical engineering and materials science at the Duke Pratt School of Engineering. "After repeated stretching, the molecules immediately refold themselves, retaining their shape and strength"......... Posted by: Kevin Permalink January 15, 2006, 8:21 PM CT Probing Combustion Process
"With a trustworthy computer model of combustion, engineers can design improved engines or fuel blends without needing to build and test so a number of different versions," said Brookhaven chemist Gregory Hall, the principal researcher for this experiment. "The database of chemical reactions needed for such a computer program is too big to be filled in strictly with measured numbers, and we have to rely on chemical rate theory to calculate much of this database. Our experiments are important for showing how far we should trust these calculations." The Chemical Physics Research Program in DOE's Office of Basic Energy Sciences funded the research, which is due would be published online today in the Journal of Chemical Physics. The chemists used an experimental technique called "sliced ion imaging" to analyze the energy flow during the fragmentation of ketene, a small molecule that acts as a stand-in for more complicated fuels in these benchmark experiments. When excited with a laser, ketene breaks apart into carbon monoxide and methylene fragments, pushing away from each other with a speed that depends on the rotational and vibrational energies of the two fragment molecules. Some of the carbon monoxide fragments are then ionized (an electron is removed) by a second laser, and the ions are accelerated toward a detector screen, where each ion shows up as a flash of light, observed with a video camera. Depending on how fast and in what direction the carbon monoxide fragments were traveling when they were born, the ions will hit a different spot on the ion-imaging detector. By analyzing the images obtained by accumulating the signals from about half a million molecules, the Brookhaven researchers can determine how energy is shared between the two fragments. They have found agreement with the predictions of a chemical rate theory called variational transition state theory, refuting some earlier work that had raised questions about this theory......... Posted by: Sarah Permalink January 15, 2006, 8:17 PM CT Filling "Nano-containers" with Liquid
A view of the nanopatterned silicon surface, showing the array of nanocavities
"Watching how a liquid adsorbs on a nanopatterned surface is one way to study the basic properties of liquids that are confined - in extremely tiny amounts - within nanoscale structures. In turn, understanding these properties will help researchers develop a number of useful fluid-based nanotechnologies," said Brookhaven physicist Oleg Gang, the paper's lead author. For example, he said, his work could help improve developing biomedical nanodevices, such as the "lab on a chip" concept, in which dime-sized microprocessor chips can mimic the functions of a true medical lab by performing tests on tiny amounts of body fluid. Oleg Gang Currently, what researchers know about the microscopic behavior of liquids on solid surfaces, known as "wetting" phenomena, is predominately based on measurements taken using structureless, flat surfaces. In those cases, the behavior of the liquid is based on the strength of attractive molecule-molecule forces known as "van der Waals interactions." But for a surface that contains a regular pattern of cavities, researchers predict that the shape of the surface influences how the liquid will fill those cavities. However, those predictions have been calculated and verified for relatively deep, millionth-of-a-meter sized cavities. This study addresses how liquids fill much shallower nanoscale sized cavities and how nanopatterning a surface affects wetting......... Posted by: Kevin Permalink January 13, 2006, 6:15 PM CT Another Step Toward Faster Communication
Optical components of the free electron laser
The work represents a key step toward a new generation of optical communication systems that would be as much as 100 times faster than current technology, bringing closer such applications as real-time telemedicine and movies on demand. While operating their terahertz modulator, the research team observed an effect that is well known in atomic physics - but until now hadn't been seen in the semiconductor materials that make up optical modulators. "This is just one piece, but potentially a very important piece, of a very high bit-rate optical communication system for telecommunications and other applications," said David Citrin, an associate professor in the School of Electrical and Computer Engineering at the Georgia Institute of Technology. "The point of the experiment was to show that we can operate a modulator at terahertz frequencies, though we are still a long way from a practical device." Supported by the National Science Foundation, the research was reported in the October 28, 2005 issue of the journal Science......... Posted by: Kevin Permalink January 13, 2006, 0:44 AM CT Music On Headphones Can Lead To Hearing Loss
Listeners should avoid blasting the sound so high that they can't hear surrounding conversations or so that others can hear the music from the listener's headphones or earbuds, says Paul R. Kileny, Ph.D., director of audiology in the U-M Department of Otolaryngology. "These portable devices are not inherently harmful to hearing because of the way they are coupled to the ear, but there are certainly safe levels at which one can listen to them," Kileny says. "My recommendation is to listen at such a level that one can still hear conversation and other people in their environment do not accuse them of shouting when they attempt to converse". The effects of listening to music turned up too loudly can be permanent, Kileny says. He notes that he and other doctors in his field are seeing more and more young people with noise-induced hearing loss. "As you pass some of these young people, you can actually hear the music radiating from under those little headphones," says Kileny, also a professor in the Department of Pediatrics and Communicable Diseases and a member of the Geriatrics Center. "That is a sure sign that the individual listening to that music is listening at a level that is too loud, and, therefore, in the long run is risky to the status of their hearing"......... Posted by: Kevin Permalink |
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