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November 23, 2006, 5:30 AM CT

On the cutting edge: Carbon nanotube cutlery

On the cutting edge: Carbon nanotube cutlery Scanning electron micrograph of a prototype "nanoknife" shows a single carbon nanotube stretched between two tungsten needles.
Researchers at the National Institute of Standards and Technology (NIST) and the University of Colorado at Boulder (CU) have designed a carbon nanotube knife that, in theory, would work like a tight-wire cheese slicer. In a paper presented this month at the 2006 International Mechanical Engineering Congress and Exposition*, the research team announced a prototype nanoknife that could, in the future, become a tabletop tool of biology, allowing scientists to cut and study cells more precisely than they can today.

For years, biologists have wrestled with conventional diamond or glass knives, which cut frozen cell samples at a large angle, forcing the samples to bend and sometimes later crack. Because carbon nanotubes are extremely strong and slender in diameter, they make ideal materials for thinly cutting precise slivers of cells. In particular, scientists might use the nanoknife to make 3D images of cells and tissues for electron tomography, which requires samples less than 300 nanometers thick.

By manipulating carbon nanotubes inside scanning electron microscopes, 21st-century nanosmiths have begun crafting a suite of research tools, including nanotweezers, nanobearings and nano-oscillators. To design the nanoknife, the NIST and CU scientists welded a carbon nanotube between two electrochemically sharpened tungsten needles. In the resulting prototype, the nanotube stretches between two ends of a tungsten wire loop. The knife resembles a steel wire that cuts a block of cheese.........

Posted by: John      Permalink         Source


November 22, 2006, 5:12 AM CT

The Power Behind Insect Flight

The Power Behind Insect Flight
Researchers from Rensselaer and the University of Vermont have discovered a key molecular mechanism that allows tiny flies and other "no-see-ums" to whirl their wings at a dizzying rate of up to 1,000 times per second. The findings were reported in last week's online early edition of the Proceedings of the National Academy of Sciences (PNAS).

"We have determined important details of the biochemical reaction by which the fastest known muscle type - insect flight muscle - powers flight," said Douglas Swank, assistant professor of biology at Rensselaer and lead author of the PNAS paper.

The findings will help scientists gain a better understanding of how chemical energy is converted into muscle movements, such as human heart muscle pumping blood. The research also could lead to novel insights into heart disease, and might ultimately serve in the development of gene therapies targeted toward correcting mutations in proteins that detrimentally alter the speed at which heart muscle fibers contract.

Since insects have been remarkably successful in adapting to a great range of physical and biological environments, in large part due to their ability to fly, the research also will interest scientists studying the evolution of flight, Swank noted. The project is supported by a three-year $240,000 grant from the National Institutes of Health and a four-year $260,000 grant from the American Heart Association.........

Posted by: Nora      Permalink         Source


November 22, 2006, 4:55 AM CT

FTC Halts Unlawful Spyware Operations

FTC Halts Unlawful Spyware Operations
Defendants involved with operations that secretly downloaded spyware that changed settings on consumers' computers, have agreed to settle Federal Trade Commission charges that their practices violated federal law. The settlements bar secret software downloads in the future, bar the operators from exploiting security vulnerabilities to download software, and bar misrepresentations. In addition, the operators will give up a total of $50,000 in ill-gotten gains.

In October 2005, the FTC charged that Odysseus Marketing, Inc. and its principal, Walter Rines, lured consumers to their Web sites by advertising bogus free software, including a program called Kazanon that purportedly allowed consumers to engage in anonymous peer-to-peer file sharing. As per the FTC, the bogus software was bundled with spyware and other unwanted software. The agency alleged that the defendants also distributed their spyware by exploiting security vulnerabilities in the Internet Explorer Web browser. The FTC charged that the defendants' spyware intercepted and replaced search results provided to users who queried popular Internet search engines, and barraged consumers with pop-up and other Internet ads. The FTC also charged that the defendants' software captured consumers' personal information such as their first and last names, addresses, e-mail addresses, telephone numbers, and Internet browsing and shopping histories, and transmitted that information to the defendants' Internet servers. Consumers were unable to locate or uninstall the defendants' spyware through reasonable means, as per the FTC.........

Posted by: John      Permalink         Source


November 22, 2006, 4:32 AM CT

First Live HDTV Broadcast From Space

First Live HDTV Broadcast From Space
Images from the world's first high definition television (HDTV) broadcast from space flashed across the screen on Nov 15th in Times Square. On Nov. 15, 2006, NASA made history with the first live HDTV broadcasts from space, in cooperation with the Japan Aerospace Exploration Agency, Discovery HD Theater and Japanese broadcast network NHK.

The two HDTV broadcasts featured Expedition 14 Commander Michael Lopez-Alegria on the International Space Station, with Flight Engineer Thomas Reiter serving as camera operator aboard the 220-mile-high laboratory.

"HDTV provides up to six times the resolution of regular analog video," said Rodney Grubbs, NASA principal investigator. "On previous missions, we've flown HDTV cameras but had to wait until after the mission to retrieve the tapes, watch the video and share it with the science and engineering community, the media and the public. For the first time ever, this test lets us stream live HDTV from space so the public can experience what its like to be there".

Known as the Space Video Gateway, the system transmits high bandwidth digital television signals to the ground that are not only spectacular, but also valuable to scientists, engineers and managers.

NASA and the Japan Aerospace Exploration Agency, along with both NHK and Discovery, are cooperating in this effort though a Space Act Agreement originally signed in 2002.........

Posted by: Edwin      Permalink         Source


November 21, 2006, 9:05 PM CT

Safer Ways To Detect Uranium Minerals

Safer Ways To Detect Uranium Minerals QUT Professor Ray Frost
The threat of 'dirty' bombs and plans to use nuclear power as an energy source have driven Queensland University of Technology researchers to discover a new, safer way of detecting radioative contamination in the ground.

Professor Ray Frost, from QUT's School of Chemical and Physical Sciences, has found a way of identifying, from a remote location, uranium deposits that have leached into the soil and water.

"The ability to be able to easily and readily detect uranium minerals, particularly secondary minerals, is of great importance particularly in today's current climate of terrorism and increased uranium mining," Professor Frost said.

"What is not usually known is that a number of uranium minerals, particularly the secondary minerals, are soluble and can translocate or move in water to areas far away from where uranium sites are found.

"This means that uranium minerals could arise in soils and sediments from unknown origins and in locations far from their origins".

Professor Frost said using a technique known as near infrared spectroscopy, radioactive minerals could be detected by researchers located far away from a contaminated site.

"Using a fibre optic probe and the near infrared spectroscopy technique, we have observed that we can detect whether uranium minerals are present in soil.........

Posted by: Edwin      Permalink         Source


November 20, 2006, 8:33 PM CT

Fascinating Twin Star Explosions

Fascinating Twin Star Explosions twin-star-explosions
Credit: NASA/Swift/Stefan Immler
Scientists using NASA's Swift satellite stumbled upon a rare sight, two supernovas side by side in one galaxy. Large galaxies typically play host to three supernovas per century. Galaxy NGC 1316 has had two supernovas in less than five months, and a total of four supernova in 26 years, as far back as the records go. This makes NGC 1316 the most prodigious known producer of supernovas.

The first supernova, still visible on the "right" in the image, was detected on June 19, 2006, and was named SN 2006dd. The second supernova, on the immediate "left" in the image, was detected on November 5 and has been named SN 2006mr. (The central bright spot is the galaxy core, and the bright object to the far left, like an earring, is a foreground star.).

NGC 1316, a massive elliptical galaxy about 80 million light years way, has recently merged with a spiral galaxy. Mergers do indeed spawn supernovas by forcing the creation of new, massive stars, which quickly die and explode. Yet all four supernovas in NGC 1316 appear to be Type Ia, a variety previously not associated with galaxy mergers and massive star formation. Scientists are intrigued and are investigating whether the high supernova rate is a coincidence or a result of the merger. Swift was launched on this date, November 20, in 2004.........

Posted by: Edwin      Permalink         Source


November 20, 2006, 5:17 AM CT

Origins of Life

Origins of Life
The origin of life lies in unique ocean reefs, and scientists from the University of Miami's Rosenstiel School of Marine & Atmospheric Science have developed an approach to help investigate them better. A new article published in the recent issue of Geology reveals how Dr. Miriam Andres' stromatolite investigation - the first of its kind - has begun to "fingerprint" ancient microbial pathways, increasing the understanding of how these reef-like structures form and offering a new way to explore the origins of these living records, which are considered to be the core of most living organisms.

Modern marine stromatolites are living examples of one of the earth's oldest and most persistent widespread ecosystems. Although rare today, these layered deposits of calcium carbonate are found in shallow marine seas throughout 3.4 billion-year-old geologic records. Ancient stromatolites represent a mineral record of carbonate chemistry and the evolution of early life. In the Geology paper, Dr. Andres and colleagues point out that incorrect assumptions have been made in interpreting stromatolite data: phototrophs, or oxygen-producers, were actually dominated by heterotrophs, or oxygen-consumers, in their contribution to stromatolite formation.

"The motivation for this study is that in ancient stromatolites, direct evidence of microbial activity is lacking," Dr. Andres explained. "Stable isotopes have provided a powerful tool to 'fingerprint' microbial pathways and better understand the sedimentary structures we see in the geologic record. Surprisingly, no study to date has documented this process for modern marine stromatolites".........

Posted by: Nora      Permalink         Source


November 20, 2006, 5:13 AM CT

Monarch Butterfly Migration And Forest Restoration

Monarch Butterfly Migration And Forest Restoration
USDA Forest Service (FS) research in the Ouachita Mountains of Arkansas suggests that decades of fire suppression have reduced the area's food supply for migrating monarch butterflies-and that restoration efforts that include prescribed burning can reverse this trend. Craig Rudolph and Ron Thill, research ecologists with the FS Southern Research Station (SRS), along with SRS ecologists Charles Ely, Richard Schaefer and J. Howard Williamson, report their findings in the latest issue of the Journal of the Lepidopterists' Society.

Every fall, masses of monarch butterflies migrate across eastern North America to remote sites in central Mexico-a long flight fuelled only by nectar from flowers still blooming on the way. In recent years, there have been concerns about the continued health of monarch populations, and of the migration itself, as land use change has altered both breeding habitat and migratory pathways.

Studies have focused on food availability for larvae, pesticides, and loss of overwintering sites in Mexico as possible threats. Less attention has been paid to how landscape-level changes affect the availability of the butterfly's preferred nectar sources along their migratory routes. In September and October, large numbers of monarchs pass through the Ouachita Mountains, a largely forested area in Arkansas and Oklahoma where fire suppression, logging, and pine production practices have altered forest structure, leading to a drastic reduction in the quality and abundance of the flowering plants the butterflies rely on for nectar.........

Posted by: Edwin      Permalink         Source


November 19, 2006, 9:30 PM CT

Wnt Reactivates Dormant Limb Regeneration

Wnt Reactivates Dormant Limb Regeneration
Chop off a salamander's leg and a brand new one will sprout in no time. But most animals have lost the ability to replace missing limbs. Now, a research team at the Salk Institute for Biological Studies has been able to regenerate a wing in a chick embryo a species not known to be able to regrow limbs - suggesting that the potential for such regeneration exists innately in all vertebrates, including humans.

Their study, published in the advance online edition of Genes and Development on Nov. 17, demonstrates that vertebrate regeneration is under the control of the powerful Wnt signaling system: Activating it overcomes the mysterious barrier to regeneration in animals like chicks that can't normally replace missing limbs while inactivating it in animals known to be able to regenerate their limbs (frogs, zebrafish, and salamanders) shuts down their ability to replace missing legs and tails.

"In this simple experiment, we removed part of the chick embryo's wing, activated Wnt signaling, and got the whole limb back - a beautiful and perfect wing," said the lead author, Juan Carlos Izpisa Belmonte, Ph.D., a professor in the Gene Expression Laboratory. "By changing the expression of a few genes, you can change the ability of a vertebrate to regenerate their limbs, rebuilding blood vessels, bone, muscles, and skin - everything that is needed".........

Posted by: Nora      Permalink         Source


November 19, 2006, 9:27 PM CT

Insights Into Periodic Table

Insights Into Periodic Table
The periodic table of chemical elements hangs in front of chemistry classrooms and in science laboratories worldwide. Yet much was unknown about its history and evolution until now.

"The moment I discovered there was this elegant, orderly chart that encompassed chemistry, I fell in love with the periodic table," said Eric Scerri, a UCLA chemist and author of the recently published "The Periodic Table: Its Story and Its Significance" (Oxford University Press). "It captured my imagination, and it still does. It is completely unique in science. Chemistry is the only field with one simple chart that embodies the essence of the field. This wonderful tool serves to organize the whole of chemistry".

Who discovered the periodic table of elements --the fundamental materials of which all matter is composed? There is no simple answer. The story begins with the ancient Greek philosophers. Aristotle, among others, identified four elements: earth, water, fire and air. Some elements -- such as iron, copper, gold and other metals -- have been known since antiquity.

Today, the periodic table has 116 elements, the most recent of which was added just last month -- an element that for now is known as element 118 for the number of protons in its nucleus, more than in any other element. (Two other elements are predicted from the existence of spaces in the periodic table, but have not yet been synthesized.).........

Posted by: Nora      Permalink         Source


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