August 19, 2009, 7:16 AM CT

First discovery using revolutionary long wavelength

Researchers from NRL's Space Science and Remote Sensing Divisions, in collaboration with scientists from the University of New Mexico (UNM) and the National Radio Astronomy Observatory (NRAO) located in Socorro, N.M., have generated the first scientific results from the Long Wavelength Demonstrator Array (LWDA). The measurements were obtained during field tests and calibration of two prototype antennas for the much larger Long Wavelength Array (LWA), which will eventually consist of nearly 13,000 similar antennas.

Utilizing radio emissions from the approximately 300 year-old Cassiopeia A (Cas A) supernova remnant (SNR)one of the brightest astronomical radio sources in the skyto establish baseline measurements, NRL scientist and National Research Council (NRC) postdoctoral fellow Dr. Jake Hartman utilized the LWDA to confirm and extend a study initiated by fellow NRL-NRC postdoc Dr. Joseph Helmboldt.

Using NRAO's Very Large Array (VLA) radio telescope, Dr. Helmboldt's research showed that the gradually weakening Cas A displays signs of a "softer" smooth, secular decrease and an apparent shorter term variability at frequencies below 100 MHz.

"Cas A has long been known to be fading, but the slower, seemingly irregular decrease at frequencies lower than 100 MHz has remained controversial," said Dr Namir Kassim, astronomer and LWA project scientist, NRL. "Dr. Hartman's discovery reaffirms this supposition and provides strong support that more frequent time sampling will be needed to determine whether the shorter term variations contain a non-random component"......... Posted by: Beverly      Read more         Source

August 16, 2009, 9:54 PM CT

Cognitive behavioral therapy improves sleep

A study in the Aug. 15 issue of the Journal of Clinical Sleep Medicine shows that the use of cognitive behavioral treatment for insomnia (CBT-I) is an effective therapy for older patients with osteoarthritis and comorbid insomnia.

Results showed that therapy improves both immediate and long-term self-reported sleep and pain in older patients with osteoarthritis and comorbid insomnia without directly addressing pain control. Participants who received CBT-I reported significantly decreased sleep latency (initially decreased by an average of 16.9 minutes and 11 minutes a year after therapy) and wake after sleep onset (initially decreased by an average of 37 minutes and 19.9 minutes a year after therapy), significantly reduced pain (initially improved by 9.7 points and 4.7 points a year after therapy) and increased sleep efficiency (initially increased by 13 percent and 8 percent a year after therapy). These improvements persisted in CBT-I patients (19 of 23) who were further assessed for sleep quality and perceived pain at a one-year follow-up visit.

As per main author Michael V. Vitiello, PhD, professor at the University of Washington in Seattle, Wash., results indicate that insomnia is not merely a symptom of osteoarthritis but rather a co-existing illness. Vitiello said improving sleep can result in an improvement in osteoarthritis, which is especially important because, at least in elderly adults, insomnia rarely exits by itself, rather it typically coexists with other illnesses, pain conditions and depression......... Posted by: Beverly      Read more         Source

July 28, 2009, 11:26 PM CT

Breakthrough Performance in Organic Light-Emitting Diode

SRI International, an independent nonprofit research institute, and Showa Denko K.K. (SDK), a Japan-based chemical industry company in partnership with Itochu Plastics Inc. (CIPS), have achieved record-breaking results using SRI's new cavity organic light-emitting diode (COLED) technology and SDK's light-emitting polymers to produce a highly efficient light source that could one day replace incandescent and fluorescent light bulbs.

SRI's COLED device is a new OLED structure designed by Dr. Yijian Shi, project team leader and senior chemist at SRI, that uses cavities to generate up to five times greater light output in comparison to traditional OLED structures. In addition, SRI's new COLED device has the potential to be two times more efficient than compact fluorescent lights, which contain mercury and present a disposal problem.

"With our new cavity design, SRI has significantly increased the efficiency of OLED devices," said Philip von Guggenberg, director of business development, SRI International. "These new results validate our strategy of focusing on new device architectures to improve the performance of OLED devices".

A combination of SDK's light-emitting polymer materials and SRI's COLED technology has enabled scientists to achieve an output of 30 lumen (a measure of light output) per watt for blue light - higher than any other reported polymer OLED result. For green light, the team has achieved more than 80 lumen per watt - about three times higher than a traditional OLED. To produce white light that is acceptable for illumination, a mix of red, green, and blue light is mandatory - with blue being the most technically challenging to produce. The results from SRI and SDK's research point to the feasibility of producing a white light source of sufficient quality at low cost......... Posted by: Beverly      Read more         Source

May 18, 2009, 5:37 AM CT

Observations of biological particles in high-altitude ice clouds

A team of UC San Diego-led atmospheric chemistry scientists moved closer to what is considered the "holy grail" of climate change science when it made the first-ever direct detection of biological particles within ice clouds.

The team, led by Kerri Pratt, a Ph.D. student of atmospheric chemistry Professor Kim Prather, who also holds appointments at Scripps Institution of Oceanography as well as the Department of Chemistry and Biochemistry at UCSD, sampled water droplet and ice crystal residues at high speeds from an aircraft flying through clouds in the skies over Wyoming in fall 2007. Analysis of the ice crystals revealed that they were made up almost entirely of either dust or biological particles such as bacteria, fungal spores and plant material. While it has long been known that microorganisms or parts of them get airborne and travel great distances, this study is the first to yield in-situ data on their participation in cloud ice processes.

Results of the Ice in Clouds Experiment Layer Clouds (ICE-L), funded by the National Science Foundation (NSF) and the National Center for Atmospheric Research (NCAR), appear May 17 in the advance online edition of the journal Nature Geoscience

"If we understand the sources of particles that nucleate clouds and their relative abundance, then we can determine the impact of these different sources on climate," said Pratt......... Posted by: Beverly      Read more         Source

Fri, 01 May 2009 02:32:01 GMT

Array Of UFO Shapes

The array is intended only to convey some idea of the variety of shapes that have appeared, it does not give an adequate impression of the relative frequencies with which the different UFO shapes have appeared. Posted by: Gerard      Read more     Source

April 29, 2009, 5:11 AM CT

Need for continual change in sustainable education reform

Any educational reform, no matter how effective it may seem today, will have to change in order to last, as per University of Chicago education researcher Jeanne Century.

The oxymoron stems from the reality of complex social processes. But this complexity is paralyzing educational reform efforts, said Century, director of science education at the University of Chicago's Center for Elementary Mathematics and Science Education.

"Even when you identify best practices, they never, ever are replicated as they move from one place to another place. They always translate in one way or another. The idea that we can identify a best practice in education and just scale it up is a dramatic oversimplification".

Century will discuss these and related issues on Wednesday, April 29, in Irvine, Calif., during her keynote address at a convocation of stakeholders in California's elementary science education system. She and her staff conduct research on the sustainability of science education reform with a grant from the National Science Foundation.

She compares the magnitude of the educational reform challenge to that of curing cancer. But people know that curing cancer is a huge problem requiring large investments of money over a long period; the perception is otherwise for educational reform......... Posted by: Beverly      Read more         Source

April 20, 2009, 9:47 PM CT

Decline in Greenhouse Gas Emissions Would Reduce Global Warming

The threat of global warming can still be greatly diminished if nations cut emissions of heat-trapping greenhouse gases by 70 percent this century, as per a new analysis.

While global temperatures would rise, the most dangerous potential aspects of climate change, including massive losses of Arctic sea ice and permafrost and significant sea-level rise, could be partially avoided.

The study, led by researchers at the National Center for Atmospheric Research (NCAR), will be published next week in the American Geophysical Union journal Geophysical Research Letters.

It was funded by the Department of Energy and the National Science Foundation (NSF), NCAR's sponsor.

"This important study, when taken with similar efforts, will help define a major challenge for society," says Cliff Jacobs of NSF's Atmospheric Sciences Division.

"This research indicates that we can no longer avoid significant warming during this century," says NCAR scientist Warren Washington, the paper's main author. "But if the world were to implement this level of emission cuts, we could stabilize the threat of climate change".

Average global temperatures have warmed by close to 1 degree Celsius (almost 1.8 degrees Fahrenheit) since the pre-industrial era. Much of the warming is due to human-produced emissions of greenhouse gases, predominantly carbon dioxide......... Posted by: Beverly      Read more         Source

April 20, 2009, 9:44 PM CT

Isolating Harmful Forms of Chemicals

Researchers studying how marine bacteria move have discovered that a sharp variation in water current segregates right-handed bacteria from their left-handed brethren, impelling the microbes in opposite directions.

This finding and the possibility of quickly and cheaply implementing the segregation of two-handed objects in the laboratory could have a big impact on industries like the pharmaceutical industry, for which the separation of right-handed from left-handed molecules can be crucial to drug safety.

"This is a remarkable example of how basic research, initially focused on understanding how bacteria interact with their environment, can lead to discoveries far beyond that envisioned," said David Garrison, director of the National Science Foundation (NSF)'s Biological Oceanography Program, which funded the research.

While single-celled bacteria do not have hands, their helical-shaped flagella spiral either clockwise or counter-clockwise, making opposite-turning flagella similar to human hands in that they create mirror images of one another.

This two-handed quality is called chirality, and in a molecule, it can make the difference between healing and harming the human body.

"This discovery could impact our understanding of how water currents affect ocean microbes, especially with respect to their ability to forage for food, since chiral effects make them drift off-course," said Roman Stocker, a marine scientist at MIT and lead investigator on the research project. "But it is also important for several industries that rely on the ability to separate two-handed molecules"......... Posted by: Beverly      Read more         Source

April 16, 2009, 5:18 AM CT

Novel Technique to Sequence Human Genome

Since the human genome was sequenced six years ago, the cost of producing a high-quality genome sequence has dropped precipitously. More recently, the National Institutes of Health called for cutting the cost to $1,000 or less, which may enable sequencing as part of routine medical care.

The obstacles to reaching that goal have been primarily technological: Researchers have struggled to figure out how to accurately read the 3 billion base pairs - the amount of DNA found in humans and other mammals - without time-consuming, inefficient methods.

Physicists at Brown University may have an answer. They introduce a novel procedure to vastly slow the DNA's movement through openings that are used to read the code. In the journal Nanotechnology, the physicists report the first experiment to move DNA through a solid-state nanopore using magnets. The approach is promising because it allows multiple segments of a DNA strand to be threaded simultaneously through numerous tiny pores and for each fragment to move slowly enough through the opening so that the base pairs can be accurately read.

Xinsheng Sean Ling "When it comes to sequencing anyone's genome, you need to do it cheaply, and you need to do it quickly," explained Xinsheng Sean Ling, professor of physics, who joined the Brown faculty in 1996. "This is a step in that direction"......... Posted by: Beverly      Read more         Source

April 9, 2009, 4:48 AM CT

Complex nucleation processes using DNA origami seeds

The construction of complex man-made objects--a car, for example, or even a pizza--almost invariably entails what are known as "top-down" processes, in which the structure and order of the thing being built is imposed from the outside (say, by an automobile assembly line, or the hands of the pizza maker).

"Top-down approaches have been extremely successful," says Erik Winfree of the California Institute of Technology (Caltech). "But as the object being manufactured requires higher and higher precision--such as silicon chips with smaller and smaller transistors--they require enormously expensive factories to be built".

The alternative to top-down manufacturing is a "bottom-up" approach, in which the order is imposed from within the object being made, so that it "grows" as per some built-in design.

"Flowers, dogs, and just about all biological objects are created from the bottom up," says Winfree, an associate professor of computer science, computation and neural systems, and bioengineering at Caltech. Along with his coworkers, Winfree is seeking to integrate bottom-up construction approaches with molecular fabrication processes to construct objects from parts that are just a few billionths of a meter in size that essentially assemble themselves.

In a recent paper in the Proceedings of the National Academy of Sciences (PNAS), Winfree and colleagues describe the development of an information-containing DNA "seed" that can direct the self-assembled bottom-up growth of tiles of DNA in a precisely controlled fashion. In some ways, the process is similar to how the fertilized seeds of plants or animals contain information that directs the growth and development of those organisms......... Posted by: Beverly      Read more         Source