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September 13, 2006, 4:37 AM CT

Surfing With Vulnerabilities

Surfing With Vulnerabilities
The next time you're sipping a latte and surfing the Net at your favorite neighborhood wireless caf, someone just a few seats away could be breaking into your laptop and causing irreparable damage to your computer's operating system by secretly tapping into your network card's unique device driver, researchers at Sandia National Laboratories in have concluded.

There is, however, some cheerful news. By role-playing the position of an adversary (also known as red teaming), Sandia researchers have demonstrated a unique "fingerprinting" technique that allows hackers with ill intent to identify a wireless driver without modification to or cooperation from a wireless device. Revealing this technique publicly, Sandia researchers hope, can aid in improving the security of wireless communications for devices that employ 802.11 networking.

Sandia is a National Nuclear Security Administration laboratory.

Wireless device drivers fraught with vulnerabilities.

Device drivers, according to Sandia security researcher Jamie Van Randwyk, are becoming a primary source of security holes in modern operating systems. Through a laboratory-directed research grant, Van Randwyk and a team of college interns set out last year to design, implement, and evaluate a technique that has proved capable of passively identifying a wireless driver used by 802.11 wireless devices without specialized equipment and in realistic network conditions. Van Randwyk presented his team's findings last month at the USENIX Security Symposium in Vancouver, B.C.........

Posted by: John      Permalink         Source


September 11, 2006, 9:48 PM CT

Insights Into Research Of Sir Issac Newton

Insights Into Research Of Sir Issac Newton Kenneth Knoespel
Known primarily for his foundational work in math and physics, Sir Issac Newton actually spent more time on research in alchemy, as well as its interrelationships with science, history and religion, and its implications for economics.

Alchemy, as Newton practiced it in the 17th and 18th centuries, was research into the nature of chemical substances and processes primarily the transmutation of materials from one type of matter to another. Newton and others conducted experiments, but also incorporated philosophical thought in their attempts to uncover the mysteries of the physical universe.

"Newton's extensive work on universal history (which presents human history as a coherent unit governed by certain immutable principles) provides an essential setting for linking his work on alchemy and his work heading England's mint in the 1690s," said Georgia Institute of Technology Professor Kenneth Knoespel, who chairs the School of Literature, Communication and Culture. "It is not at all farfetched to think of history as a kind of alchemical process that looks to the creation of value and wealth".

Knoespel will present an invited talk titled "Newton's alchemical work and the creation of economic value" at 9 a.m. Pacific time Sept. 11 at the American Chemical Society's 232nd national meeting in San Francisco. The talk is part of a session dedicated to scholarship based on the unpublished manuscripts of Newton, most of which are housed at the University of Cambridge and in the Edelstein Center at Hebrew University in Jerusalem. For the past 15 years, Knoespel has studied both collections -- some portions of which weren't available to scholars until the 1970s.........

Posted by: John      Permalink         Source


September 11, 2006, 9:41 PM CT

Bio-sensitive Nanofibers

Bio-sensitive Nanofibers
Detecting bacteria, viruses and other dangerous substances in hospitals, airplanes and other commonly contaminated places could soon be as easy as wiping a napkin or paper towel across a surface, says a researcher from Cornell University.

"It's very inexpensive, it wouldn't require that someone be highly trained to use it, and it could be activated for whatever you want to find," said Margaret Frey, the Lois and Mel Tukman Assistant Professor of Fiber Science and Apparel Design at Cornell. "So if you're working in a meat-packing plant, for instance, you could swipe it across some hamburger and quickly and easily detect E. coli bacteria." She reported on the research at the American Chemical Society's national meeting today (Sept. 11) in San Francisco.

Once fully developed, the biodegradable absorbent wipe would contain nanofibers containing antibodies to numerous biohazards and chemicals and would signal by changing color or through another effect when the antibodies attached to their targets. Users would simply wipe the napkin across a surface; if a biohazard were detected, the surface could be disinfected and retested with another napkin to be sure it was no longer contaminated.

In work conducted with Yong Joo, assistant professor of chemical and biomolecular engineering, and Antje Baeumner, associate professor of biological and environmental engineering, both at Cornell, Frey developed nanofibers with platforms made of biotin, a part of the B vitamin complex, and the protein streptavidin, which can hold the antibodies. Composed of a polymer compound made from corn, the nanofibers could be incorporated into conventional paper products to keep costs low. Nanofibers, with diameters near 100 nanometers (a nanometer is one-billionth of a meter, or about three times the diameter of an atom), provide extremely large surface areas for sensing and increased absorbency compared with conventional fibers.........

Posted by: John      Permalink         Source


September 9, 2006, 10:30 AM CT

Rice Domestiction Confiirmed

Rice Domestiction Confiirmed Photo courtesy USDA
Biologists from Washington University in St. Louis and their collaborators from Taiwan have examined the DNA sequence family tree of rice varieties and have determined that the crop was domesticated independently at least twice in various Asian locales.

Jason Londo, Washington University in Arts & Sciences biology doctoral candidate, and his adviser, Barbara A. Schaal, Ph.D., Washington University Spencer T. Olin Professor of Biology in Arts & Sciences, ran genetic tests of more than 300 types of rice, including both wild and domesticated, and found genetic markers that reveal the two major rice types grown today were first grown by humans in India and Myanmar and Thailand (Oryza sativa indica) and in areas in southern China (Oryza sativa japonica).

Schaal said that she was surprised and "delighted" by their results.

"People have moved rice around so much and the crop crosses with its wild ancestors pretty readily, so I was fully prepared to see no domestication signal whatsoever,," Schaal said.

"I would have expected to see clustering of the cultivated rice, but I was delighted to see geographical clustering of the wild rice. I was thrilled that there was even genetic structure in the wild rice".

In contrast to rice, other staple crops such as wheat, barley and corn appears to have been domesticated just once in history.........

Posted by: Nora      Permalink         Source


September 9, 2006, 7:48 AM CT

One of smallest stellar companions

One of smallest stellar companions This NASA/ESA Hubble Space Telescope image shows one of the smallest objects ever seen around a normal star.
Astronomers using the NASA/ESA Hubble Space Telescope have photographed one of the smallest objects ever seen around a normal star beyond our Sun. Weighing in at 12 times the mass of Jupiter, the object is small enough to be a planet. The riddle is that it is also large enough to be a brown dwarf, a failed star.

The Hubble observation of the diminutive companion to the low-mass red dwarf star CHRX 73 is a dramatic reminder that astronomers do not have a consensus in deciding which objects orbiting other stars are truly planets - even though they have recently provided the definition of 'planet' for objects inside our Solar System.

Kevin Luhman of Penn State University, USA, leader of the international team that found the object (called CHRX 73 'B') is casting his vote for a brown dwarf. "New, more sensitive telescopes are finding smaller and smaller objects of planetary-mass size," said Luhman. "These discoveries have prompted astronomers to ask the question, are planetary-mass companions always planets?".

Some astronomers suggest that an extra-solar object's mass determines whether it is a planet. Luhman and others advocate that an object is only a planet if it formed from the disk of gas and dust that commonly encircles a newborn star. Our Solar System planets formed 4.6 thousand million years ago out of a dust disk around our Sun.........

Posted by: Edwin      Permalink         Source


September 7, 2006, 9:08 PM CT

Photovoltaics From Organic Semiconductors

Photovoltaics From Organic Semiconductors Schematic of a junction between two organic semiconductors
Malliaras lab/Cornell Universit
Imagine T-shirts that light up, or a beach umbrella that collects solar energy to run a portable TV. How about really cheap solar collectors for the roof?

All this and more could come from cutting-edge research at Cornell that demonstrates a new type of organic semiconductor device which shows electroluminescence and acts as a photovoltaic cell. The device is the first to use an "ionic junction," which researchers say could lead to improved performance. Since organic semiconductors can be made in thin, flexible sheets, they could create displays on cloth or paper.

"Flexible means low-cost fabrication," said George Malliaras, Cornell associate professor of materials science and engineering, in whose laboratory the research was done. And that means another result of the research could be mass-produced, inexpensive solar cells.

The work is described in the Sept. 7 issue of the journal Science in a paper by Cornell graduate researchers Daniel Bernards and Samuel Flores-Torres, Hector Abruña, the E. M. Chamot Professor of Chemistry and Chemical Biology at Cornell, and Malliaras.

Semiconductors -- organic or otherwise -- are materials that contain either an excess of free electrons (N-type) or "holes" (P-type). Holes are spaces where an atom ought to have an electron but doesn't, representing a positive charge. N- and P-type materials can be joined to form diodes and transistors. The Cornell researchers went a step further by making a diode out of organic semiconductors that also contain free ions (molecules with an electrical charge). They laminated together two organic layers, one that contained free positive ions and the other negative ions. They then added thin conducting films on the top and bottom; the top conductor is transparent to allow light in and out.........

Posted by: John      Permalink         Source


September 7, 2006, 5:13 AM CT

showing off the Laser Nanoantenna

showing off the Laser Nanoantenna
Scientists from Harvard University is showing off a new photonic device with a wide range of potential commercial applications, including dramatically higher capacity for optical data storage. This device is termed a plasmonic laser antenna, and the design consists of a metallic nanostructure, known as an optical antenna, integrated onto the facet of a commercial semiconductor laser.

This research, which is spearheaded by two research groups led by Ken Crozier, assistant professor of electrical engineering, and Federico Capasso, Robert L. Wallace Professor of Applied Physics and Vinton Hayes Senior Research Fellow in Electrical Engineering, these findings appear in the journal Applied Physics Letters. The researchers have also filed for U.S. patents covering this new class of photonic devices.

"The optical antenna collects light from the laser and concentrates it to an intense spot measuring tens of nanometers, or about one-thousandth the width of a single human hair," says Crozier. "The device could be integrated into optical data storage platforms and used to write bits far smaller than what's now possible with conventional methods. This could lead to vastly increased storage capacities in the terabyte range (a thousand gigabytes)".

Writable CDs and DVDs are a popular means for storing and backing up data, but the storage density is limited by the resolution limit of conventional optics. The optical antenna offers a substantial improvement in spatial resolution, which in turn leads to increased storage density. While optical antennas are similar to conventional antennas used for wireless communications (Wi-Fi), they are much smaller in scale -- only a few hundred nanometers across. Moreover, optical antennas operate in the visible and infrared portion of the electromagnetic spectrum; these wavelengths are far smaller than the wavelengths used in Wi-Fi.........

Posted by: John      Permalink         Source


September 7, 2006, 5:05 AM CT

Our Ancestor's Sense Of Their World?

Our Ancestor's Sense Of Their World? Padana, a young female orangutan at the Leipzig Zoo, who was one of the research subjects.
How did our evolutionary ancestors make sense of their world? What strategies did they use, for example, to find food? Fossils do not preserve thoughts, so we have so far been unable to glean any insights into the cognitive structure of our ancestors. However, in a study recently published in Current Biology (September 5, 2006), researchers at the Max Planck Institute for Psycholinguistics and their colleagues at the Max Planck Institute for Evolutionary Anthropology were able to find answers to these questions using an alternative research method: comparative psychological research. In this way, they discovered that some of the strategies shaped by evolution are evidently masked very early on by the cognitive development process unique to humans.

Being able to remember and relocate particular places where there is food is an asset to any species. There are two basic strategies for remembering the location of something: either remembering the features of the item (it was a tree, a stone, etc.), or knowing the spatial placement (left, right, middle, etc.). All animal species tested so far - from goldfish, pigeons and rats though to humans - seem to employ both strategies. However, if the type of recall task is designed so that the two strategies are in opposition, then some species (e.g. fish, rats and dogs) have a preference for locational strategies, while others (e.g. toads, chickens and children) favor those which use distinctive features.........

Posted by: Nora      Permalink         Source


September 6, 2006, 9:57 PM CT

Dark Matter Proof in doubt

Dark Matter Proof in doubt
When Douglas Clowe of the University of Arizona in Tucson announced on 21 August that his team had "direct proof of dark matter's existence", it seemed the issue had been settled. Now proponents of the so-called modified theories of gravity, who explain the motion of stars and galaxies without resorting to dark matter, have hit back and are suggesting that Clowe's team has jumped the gun.

"One should not draw premature conclusions about the existence of dark matter without a careful analysis of alternative gravity theories," writes John Moffat, of the University of Waterloo in Ontario, Canada, who pioneered an alternative theory of gravity known as MOG (www.arxiv.org/astro-ph/0608675).

The controversy centres on the pattern of gravitational lensing, or the bending of light, around the Bullet cluster of galaxies, which formed from the collision of two clusters. While most of the Bullet cluster's visible mass lies in a pool of hot gas near the centre, galaxies can also be seen on either side. Clowe's study of lensing indicates that most of the mass is contained in the two lobes, rather than in the pool of gas. The team says this is evidence of dark matter surrounding the galaxies.

Moffat claims that his MOG theory can explain the Bullet cluster without an ounce of dark matter. In MOG, gravity acts as predicted by Newton's inverse square law up to a certain distance from the gravitating mass, after which it gets a little stronger. In the Bullet cluster, the complex arrangement of galaxies and hot gas combines to make gravity strongest in the lobes, so that is where the lensing would be most apparent. Moffat has worked this out for the Bullet cluster using a.........

Posted by: John      Permalink         Source


September 6, 2006, 9:49 PM CT

How safe is drinking water?

How safe is drinking water?
Are disinfection by-products (DBPs) in drinking water harmful to an unborn fetus? According to a study in the recent issue of the American Journal of Epidemiology (available online September 5), a team of researchers at the University of North Carolina School of Public Health headed by David A. Savitz, Ph.D., Director of the Center of Excellence in Epidemiology, Biostatistics, and Disease Prevention at MSSM, and formerly Chair of the Department of Epidemiology at the University of North Carolina at Chapel Hill, have determined that drinking water DBPs -- in the range commonly encountered in the US -- do not affect fetal survival. This finding is particularly important because previous research has suggested that exposure to elevated levels of drinking water DBPs might cause pregnancy loss.

The interaction of chlorine with organic material in raw water supplies produces chemical DBPs of health concern, including trihalomethanes (THMs) and haloacetic acids (HAAs). Several epidemiological studies have addressed potential reproductive toxicity of DBPs. The strongest support in ealier studies was noted for pregnancy loss, including stillbirth.

Researchers looked at three locations with varying DBP levels and evaluated 2,409 women in early pregnancy to assess tap water DBP concentrations, water use, other risk factors and pregnancy outcome. Tap water concentrations were measured in the distribution system on a weekly or biweekly basis. DBP concentration and ingested amount, bathing/showering and integrated exposure that included ingestion and bathing/showering were considered. Based on 258 pregnancy losses, the finding did not show an increased risk of pregnancy loss in relation to ingested amounts of DBPs.........

Posted by: Edwin      Permalink         Source


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