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March 30, 2006, 4:04 PM CT

Bridging Semiconductor Chips And Nerve Cells

Bridging Semiconductor Chips And Nerve Cells

Hybrid neuroelectronic devices will be the basis for future information technology relying on the plasticity of networks formed by mammalian neurons in culture. Microelectronic implants interfaced with neurons in the nervous tissue will become sophisticated neuroprostheses able to rescue impairments of the human nervous system.

The present project deals with the fundamental aspect of electronic interfacing of microstructured silicon chips to rat neurons in culture. Its focus is the optimization of electrical coupling in both directions, from excited mammalian neurons to transistors and from stimulation areas on the chip to the cells. This will be achieved with the expression of mutated sodium channels lacking inactivation in the neurons and with the induction of channels accumulation at the neuron-silicon interface. The use of highly integrated CMOS(Complementary Metal-Oxide Semiconductor) chips is envisaged.........

Posted by: John      Permalink         Source


March 29, 2006, 10:11 PM CT

dark energy and inflation of the universe

dark energy and inflation of the universe
Looking back 13.7 billion years, astronomers have collected data that tells us, with greater precision than ever before, what happened in the first two-trillionths of a second after the big bang. The data agrees very well with theoretical predictions and may tell us something about the way the universe is behaving today, particularly why it is expanding faster than it ought to be.

"Observation is helping us constrain the theories," said Rachel Bean, Cornell assistant professor of astronomy, who is both a cosmology theorist and a member of the Wilkinson Microwave Anisotropy Probe (WMAP) team, which on March 10 released a high-resolution picture of the cosmic microwave background radiation (CMB), a sort of signature of the big bang.

For cosmologists in general, the WMAP data confirms a widely held theory called the Lambda-CDM (cold dark matter) model, a mathematical description of how the big bang might have played out. For Bean, it throws light on her efforts to explain "dark energy." Recent observations of supernovae suggest that the expansion of the universe is not just "coasting" from the big bang, but that the expansion is accelerating. Some unknown energy source is exerting a force contrary to gravity. Theorists postulate a cosmological constant -- a fundamental property of space -- or something called quintessence -- a sort of energy field.........

Posted by: Edwin      Permalink         Source


March 29, 2006, 10:04 PM CT

Properties Of Most Popular Conducting Plastic

Properties Of Most Popular Conducting Plastic
Steadily increasing the length of a purified conducting polymer vastly improves its ability to conduct electricity, report researchers at Carnegie Mellon University, whose work appeared March 22 in the Journal of the American Chemical Society. Their study of regioregular polythiophenes (RRPs) establishes benchmark properties for these materials that suggest how to optimize their use for a new generation of diverse materials, including solar panels, transistors in radio frequency identification tags, and light-weight, flexible, organic light-emitting displays.

"We found that by growing very pure, single RRP chains made of uniform small units, we dramatically increased the ability of these polymers to conduct electricity," said Richard D. McCullough, who initially discovered RRPs in 1992. "This work establishes basic properties that researchers everywhere need to know to create new, better conducting plastics. In fact, designing materials based on these results could completely revolutionize the printable electronics industry".

"Our results are very significant, since they cast new light on the mechanism by which polymers conduct electricity," said Tomasz Kowalewski, associate professor of chemistry and senior author on the study.

Unlike plastics that insulate, or prevent, the flow of electrical charges, conducting plastics actually facilitate current through their nanostructure. Conducting plastics are the subject of intense research, given that they could offer light-weight, flexible, energy-saving alternatives for materials used in solar panels and screen displays. And because they can be dissolved in solution, affixed to a variety of templates like silicon and manufactured on an industrial scale, RRPs are considered among the most promising conducting plastics in nanotech research today, according to McCullough, dean of the Mellon College of Science and professor of chemistry.........

Posted by: John      Permalink         Source


March 25, 2006, 11:33 AM CT

A Gadget For The Heart

A Gadget For The Heart

HeartWare is developing a family of implantable mechanical circulatory assist devices or "blood pumps", aimed at treating patients with congestive heart failure. Heart failure is one of the leading causes of death in the developed world, affecting over 10 million people globally.

HeartWare's lead product, the HVAD, is the smallest full-output "third generation" circulatory assist device in development. Having completed extensive pre-clinical studies, the HVAD will begin human clinical trials in early 2006. HeartWare's "next generation" device - the MVAD or Miniaturized VAD - is expected to begin clinical trials in approximately two years. The MVAD is one tenth the size of the HVAD. Small size is a key competitive advantage as it facilitates a relatively fast surgical implantation procedure, enhances patient quality of life, and expands the range of patients who might be implanted with the device.

HeartWare listed on the Australian Stock Exchange (ASX: HTW) on 31 January 2005, raising A$32.4 million (US$24.95 million). The Company's Corporate Head Office is in Sydney, Australia and its Operations Centre is in Miami, USA.........

Posted by: John      Permalink         Source


March 25, 2006, 10:59 AM CT

Did "Dark Matter" Create the First Stars?

Did Fig.: Head of the "guitar nebula". The formation contains a fast moving pulsar followed by a tail of gas. Biermann and Kusenko’s postulations about dark matter could explain puzzlingly high pulsar velocities, which lead to such cone-shaped features. Images are from the Planetary Camera aboard the Hubble Space Telescope in 1994 (left) and 2001 (right).

Image: Hubble Space Telescope (NASA/ESA), Shami Shatterjee 200
Researchers discovered that neutrinos have mass through neutrino oscillation experiments. This led to the postulation that "sterile" neutrinos exist - also known as right-handed neutrinos. They do not participate in weak interactions directly, but do interact through their mixing with ordinary neutrinos. The total number of sterile neutrinos in the universe is unclear. If a sterile neutrino only has a mass of a few kiloelectronvolts (1 keV is a millionth of the mass of a hydrogen atom), that would explain the huge, missing mass in the universe, sometimes called "dark matter". Astrophysical observations support the view that dark matter is likely to consist of these sterile neutrinos.

Biermann and Kusenko's theory sheds light on many still unexplained astronomical puzzles. First of all, during the big bang, the mass of neutrinos created in the Big Bang would equal what is needed to account for dark matter. Second, these particles could be the solution to the long-standing problem of why pulsars move so fast.

Pulsars are neutron stars rotating at a very high velocity. They are created in supernova explosions and normally are ejected in one direction. The explosion gives them a "push", like a rocket engine. Pulsars can have velocities of hundreds of kilometres per second - or sometimes even thousands. The origin of these velocities remains unknown, but the emission of sterile neutrinos would explain the pulsar kicks.........

Posted by: Edwin      Permalink         Source


March 24, 2006, 0:08 AM CT

European Robotics Under The Spotlight

European Robotics Under The Spotlight
The ExoMars rover will be ESA's field biologist on Mars. Its aim is to further characterise the biological environment on Mars in preparation for robotic missions and then human exploration. This mission calls for the development of a Mars orbiter
The European Robotic Arm (ERA) will be delivered to Russia this summer in preparation for a launch to the ISS in 2007. ESA and Dutch Space have organised the European Robotics Media Day for 5 April to provide the media with the opportunity to become acquainted with ERA and the engineers behind this ambitious project.

After its launch in November 2007, the 11-metre long robotic arm will perform a variety of tasks outside the ISS. With the ability to move up to 8 tonnes of equipment, ERA will play a key role in the continued construction of the ISS and will be used to move experimental equipment to different external locations. In addition, ERA will be used to move astronauts and cosmonauts around during spacewalks and use its video cameras to carry out inspections of external space station surfaces. ERA therefore has an important role to play in the maintenance and scientific utilisation of the ISS.

These uses of ERA highlight the impact that robotics has on human spaceflight missions. Robotic equipment can be used to undertake certain work in the harsh environment of space that is not suitable or possible to be carried out by astronauts, and also assists astronauts in a range of tasks to help reduce the amount of time needed for spacewalk activities.

Along with the European Columbus laboratory and the Automated Transfer Vehicle (ATV), ERA is one of ESA's main contributions to the ISS. With its seven joints and an impressive concentration of tools and electronics, the robotic arm has the flexibility to move hand-over- hand between fixed base points around the Russian segment of the International Space Station in order to perform its tasks. This flexibility is added to by the fact that ERA can be operated from inside or outside the ISS and can be controlled either in real-time or pre-programmed.........

Posted by: Edwin      Permalink         Source


March 6, 2006, 11:57 PM CT

Smallest Triceratops Skull Described

Smallest Triceratops Skull Described
With its big, hockey puck-sized eyes, shortened face and nubby horns, it was probably as cute as a button - at least to its mother, a three-horned dinosaur called Triceratops that could weigh as much as 10 tons and had one of the largest skulls of any land animal on the planet.

Visitors to the University of California, Berkeley's Valley Life Sciences Building now can judge for themselves. A cast of the foot-long skull from the youngest Triceratops fossil ever found is on display in the building's Marian Koshland Bioscience and Natural Resources Library. The actual skull, also at UC Berkeley and in fragments, is described by campus paleontologist Mark Goodwin in the recent issue of the Journal of Vertebrate Paleontology.

Mounted in the library's entryway, the diminutive skull, likely from a year-old, three-foot-long baby, is dwarfed by the more than six-foot-long skull of a mature Triceratops. Standing menacingly outside the library's doors is a life-size cast of Triceratops' nemesis, Tyrannosaurus rex.

Despite the pup's size, its remains are telling Goodwin a lot about how dinosaurs grew, the purpose of their head ornaments and the characteristics of their ancestors. In particular, since the horns and frill are present from a very early age, it is unlikely they were used exclusively for sexual display, he said.........

Posted by: Nora      Permalink         Source


February 15, 2006, 0:16 AM CT

Einstein Was Right Again

Einstein Was Right Again: An instrument called GAMS4, originally designed and built at NIST and now located at Institut Laue Langevin in France, was used in experiments that helped to confirm Einstein’s famous equation E=mc2.
Albert Einstein was correct in his prediction that E=mc2, as per researchers at the Massachusetts Institute of Technology (MIT), the Commerce Department's National Institute of Standards and Technology (NIST), and the Institute Laue Langevin, Genoble, France (ILL) who conducted the most precise direct test ever of what is perhaps the most famous formula in science.

In experiments described in the Dec. 22, 2005, issue of Nature,* the scientists added to a catalog of confirmations that matter and energy are related in a precise way. Specifically, energy (E) equals mass (m) times the square of the speed of light (c2), a prediction of Einstein's theory of special relativity. By comparing NIST/ILL measurements of energy emitted by silicon and sulfur atoms and MIT measurements of the mass of the same atoms, the researchers found that E differs from mc2 by at most 0.0000004, or four-tenths of 1 part in 1 million. This result is "consistent with equality" and is 55 times more accurate than the prior best direct test of Einstein's formula, as per the paper.

Such tests are important because special relativity is a central principle of modern physics and the basis for a number of scientific experiments as well as common instruments like the global positioning system. Other scientists have performed more complicated tests of special relativity that imply closer agreement between E and mc2 than the MIT/NIST/ILL work, but additional assumptions are mandatory to interpret their results, making these prior tests arguably less direct.........

Posted by: Nora      Permalink         Source


February 13, 2006, 11:05 PM CT

Canada's Ultimate Light Ruler

Canada's Ultimate Light Ruler
For NRC researchers turning on the lights is never a simple task. They inevitably ask what kind of light and how much? Which is why they're so excited about a new tool that will soon be Canada's ultimate light ruler.

Called an ultra high-temperature blackbody, this rare physics tool now being readied at the NRC Institute for National Measurement Standards (NRC-INMS) in Ottawa will soon be one of the world's most accurate ways to measure ultraviolet, or UV, light. These UV measurements are critical for a wide range of environmental and health issues, emerging industrial technologies, and regulatory requirements pertaining to global trade.

While it's called a high-temperature blackbody, it's all about measuring light. All objects emit some form of electromagnetic radiation. The electromagnetic radiation of a high-temperature blackbody is predominantly in the optical radiation region. This region ranges from the infrared through the visible spectrum to the UV. While you're reading this at room temperature your body is emitting invisible infrared radiation that would be visible with infrared, or "night", goggles. What's special about a blackbody is that it's a perfect emitter. When it's heated, at any particular temperature it emits a distinct amount of energy at each wavelength of light. Thus if you know the blackbody's temperature you can use a physics calculation to determine the amount of light being emitted at any wavelength.........

Posted by: Nora      Permalink         Source


February 11, 2006, 3:24 PM CT

Science Careers For Women

Science Careers For Women
Women continue to be underrepresented in science and technology. Research shows that girls and young women lose interest in subjects and fields of study leading to scientific and technical careers long before they enter college. The Science Careers in Search of Women Conference was conceived to reach out and engage high school women and encourage them to consider careers in science and technology. Emphasis will be on exploring career opportunities and options in science and technology. In addition, information on employment trends and educational requirements will be presented. Speakers and panelists will come from a variety of scientific and engineering disciplines. Ample time will be allowed for participants to meet with speakers and panelists to learn firsthand about life's rewards for women in science. The Conference will be held at Argonne National Laboratory, located about 25 miles southwest of downtown Chicago.

Argonne National Laboratory is a large multiprogram laboratory operated by the University of Chicago for the U.S. Department of Energy. Argonne's mission is to serve DOE and national security by advancing the frontiers of knowledge, by creating and operating forefront scientific user facilities, and by providing innovative and effective approaches and solutions to energy, environmental, and security challenges to national and global well-being, in the near and long term, as a contributing member of the DOE laboratory system.........

Posted by: Nora      Permalink         Read more....


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