June 13, 2007, 11:59 AM CT

Ancient Long-necked Gliding Reptile

The fossilized bones of a previously unknown, 220 million-year-old long-necked, gliding reptile may remain forever embedded in stone, but thanks to an industrial-size Computerized axial tomography scanner at Penn State's Center for Quantitative Imaging, the bone structure and behavior of these small creatures are now known.

The new gliding reptile is named Mecistrotrachelos apeoros meaning "soaring, long-necked" and was found at the Solite Quarry that straddles the Virginia-North Carolina border. The scientists report in today's (June 12) issue of the Journal of Vertebrate Paleontology that the "new specimens are embedded in a hard dolomitized dark gray, silty mudstone, and only faint impressions of the bones can be seen at the surface. Repeated attempts to remove the matrix using both mechanical and chemical techniques have been unsuccessful".

"The fossils sit on sheets of stone less than a quarter inch thick," says Tim M Ryan, research associate in anthropology and member of Penn States Center for Quantitative Imaging. "The color of the bones is the same as the color of the surrounding matrix which makes preparation difficult".

The specimens, which were found by Nick Fraser of the Virginia Museum of Natural History, came to Penn State to be scanned on the specialized Computerized axial tomography scanner......... Posted by: William      Read more         Source

June 13, 2007, 8:34 AM CT

NASA satellites watch as China constructs giant dam

Some call it the eighth wonder of world. Others say it's the next Great Wall of China. Upon completion in 2009, the Three Gorges Dam along Chinas Yangtze River will be the world's largest hydroelectric power generator and one of the few man-made structures so enormous that it's actually visible to the naked eye from space. NASA's Landsat satellites have provided detailed, vivid views of the dam since construction began in 1994.

The Yangtze River is the third largest river in the world, stretching more than 3,900 miles across China before reaching its mouth near Shanghai. Historically, the river has been prone to massive flooding, overflowing its banks about once every ten years. During the 20th century alone, Chinese authorities estimate that some 300,000 people were killed from Yangtze River floods. The dam is designed to greatly improve flood control on the river and protect the 15 million people and 3.7 million acres of farmland in the lower Yangtze flood plains.

Observations from the NASA-built Landsat satellites provide an overview of the dam's construction. The first image shows the region previous to start of the project. By 2000, construction along each riverbank was underway, but sediment-filled water still flowed through a narrow channel near the rivers south bank. The 2004 images show limited development of the main wall and the partial filling of the reservoir, including numerous side canyons. By mid-2006, construction of the main wall was completed and a reservoir more than 2 miles (3 kilometers) across had filled just upstream of the dam......... Posted by: Tyler      Read more         Source

June 13, 2007, 8:19 AM CT

Explaining Recent Temperature, Climate Extremes

Using an ocean of data, sophisticated mathematical models and supercomputing resources, scientists at the Department of Energy's Oak Ridge National Laboratory are putting climate models to the test with particular focus on weather extremes.

Ultimately, the new methodology developed by Auroop Ganguly and his colleagues could help determine to what extent there is a correlation between human activity and climate change. For now, however, scientists are concentrating on how climate models fare when in comparison to actual observations recorded between 1940 and 2005 and whether there are any connections between the extremes.

"Once we understand the nature of these connections our hope is that we will be able to determine if there is a relation between two extreme weather events - like heat waves and droughts," said Ganguly, a member of the Computational Sciences and Engineering Division. "We may then be able to determine whether there will be more intense storms, hurricanes or floods, and this information could perhaps be used as an early warning tool or to help develop policies."

While traditional climate models may not be particularly useful for predicting extremes in general and rainfall extremes in particular, the statistical approach outlined in the journal Advances in Water Resources represents a big step in the direction of modeling rainfall extremes from observations and climate model simulations. Ganguly, who led the research team, believes the technique opens a world of possibilities......... Posted by: Tyler      Read more         Source

June 12, 2007, 5:00 AM CT

Sleep restriction affects children's speech

Research examining the impact of sleep in school-age children suggests that even mild sleep loss produces marked deficits in their cognitive development and functioning. Sleep restriction can alter children's initial stages of speech perception, which could contribute to disruptions in cognitive and linguistic functioning skills necessary for reading and language development and comprehension, as per a research abstract that will be presented Tuesday at SLEEP 2007, the 21st Annual Meeting of the Associated Professional Sleep Societies (APSS).

Rachel Waford, of the University of Louisville, who authored the study, recorded event-related potentials, as a measure of neurocognitive development, from 32 children six-to-seven years of age while they listened to the following computer-generated speech syllables: /ba/, /da/ and /ga/.

The results showed that those children not getting an adequate amount of sleep were more likely to phonetically code incorrectly different speech sounds.

"Our research has shown that even minor sleep loss of one hour less per night for seven nights contributes to disruptions in neurocognitive functioning," said Waford. "The early school years are crucial windows that determine future learning. Therefore, it is imperative that children in this age range are well-rested to prepare for the demands of the school day."........ Posted by: Sean      Read more         Source

June 10, 2007, 9:24 PM CT

Sound Waves to Ignite Sun's Ring of Fire

Sound waves escaping the sun's interior create fountains of hot gas that shape and power a thin region of the sun's atmosphere which appears as a ruby red "ring of fire" around the moon during a total solar eclipse, as per research funded by the National Science Foundation (NSF) and NASA.

The results are presented today at the American Astronomical Society's Solar Physics Division meeting in Hawaii.

This region, called the chromosphere because of its color, is largely responsible for the deep ultraviolet radiation that bathes the Earth, producing the atmosphere's ozone layer.

It also has the strongest solar connection to climate variability.

"The sun's interior vibrates with the peal of millions of bells, but the bells are all on the inside of the building," said Scott McIntosh of the Southwest Research Institute in Boulder, Colo., lead member of the research team. "We've been able to show how the sound can escape the building and travel a long way using the magnetic field as a guide".

The new result also helps explain a mystery that's existed since the middle of the last century -- why the sun's chromosphere (and the corona above) is much hotter than the visible surface of the star. "It's getting warmer as you move away from the fire instead of cooler, certainly not what you would expect," said McIntosh......... Posted by: Brooke      Read more         Source

June 10, 2007, 9:15 PM CT

Aquatic Systems Buried Under Antarctic Ice

The National Science Foundation (NSF) should work within the environmental framework of the international Antarctic Treaty system to develop a global scientific consensus on minimally disruptive ways to investigate one of the "last unexplored places on Earth"--a unique system of lakes, and the aquatic systems that may connect them, buried thousands of meters under the Antarctic ice sheet--as per a newly released report.

To avoid contaminating these lakes and other features, which researchers have only recently discovered and which have been cut off from the outside world for millions of years, the report calls for NSF to work with international scientific organizations and Treaty signatories to develop a management plan for any potential exploration efforts and, as part of that plan, "ensure that the environmental management of subglacial environments is held to the highest standards".

The report, "Exploration of Antarctic Subglacial Aquatic Environments: Environmental and Scientific Stewardship," was released in early May by the National Research Council of the National Academies of Science.

But before any efforts are made to take any samples, the report stresses, much more detailed surveys need to be made to catalogue the subglacial aquatic network and allow it to be afforded Treaty protection. Such a survey, while enabling the protecting of the entire system, would also allow for designating certain features more useful for scientific research and presenting less of a risk of widespread contamination of a subglacial "watershed"......... Posted by: Tyler      Read more         Source

June 10, 2007, 9:11 PM CT

Nitrate in Lake Superior

Nitrate levels in Lake Superior, which have been rising steadily over the past century, are about 2.7 percent of the way toward making the lake's water unsafe to drink, as per a research studyby University of Minnesota (UMN) researchers.

The study, funded by the National Science Foundation (NSF), is published online this week in the journal Geophysical Research Letters.

The complexity of the causes underlying the increase makes it difficult to predict when the water could become unhealthy. The trend is a concern because Lake Superior contains 10 percent of the Earth's supply of surface fresh water.

Eventhough everyone is exposed to small, harmless amounts of nitrate from eating fruits and vegetables, nitrate contamination of drinking water can expose people to harmful levels.

Too much nitrate can reduce blood levels of oxygen, which poses a risk to infants and children or adults with lung or cardiovascular disease. Consuming excess nitrate over long periods of time is also suspected of causing cancer.

A compound made from nitrogen and oxygen, nitrate is a component of agricultural fertilizers and is generated by fossil fuel combustion. Nitrate in Lake Superior has increased about five-fold since the earliest measurements in 1906......... Posted by: Tyler      Read more         Source

June 10, 2007, 8:21 PM CT

High-Tech Help From Rescue Robot

National Institute of Standards and Technology (NIST) engineers are organizing the fourth in a series of Response Robot Evaluation Exercises for urban search and rescue (US&R) responders to be held on June 18-22, 2007, at Texas A&M's "Disaster City" training facility in College Station, Texas. These events, sponsored by the Department of Homeland Security's (DHS) Science and Technology Directorate, test robot performance on emerging standard test methods using actual training scenarios for emergency responders. The results will be used to refine the test methods, and in developing usage guides that match specific kinds of US&R robots to particular disaster scenarios.

This exercise will use two Disaster City training scenarios. A simulated structural collapse of a municipal building will allow responders to deploy robots to search for victims and assist in "rendering the structure safe" for responders to extricate those victims. This will require robots to face a variety of challenges as they traverse complex and confined spaces within the structure's semi-collapsed walls, sloping floors, rubble and voids while searching for victims. The robots will be deploying high-tech sensors such as laser scanners to capture the size and shape of interior voids to help structural engineers set up shoring supports......... Posted by: Kevin      Read more         Source

June 10, 2007, 8:18 PM CT

New Quantum Key System Combines Speed, Distance

Scientists at the National Institute of Standards and Technology (NIST) have built a prototype high-speed quantum key distribution (QKD) system, based on a new detector system that achieves dramatically lower noise levels than similar systems. The new system, they say, can perform a theoretically unbreakable "one-time pad" encryption, transmission and decryption of a video signal in real-time over a distance of at least 10 kilometers.

Key distribution-the problem of ensuring that both the sender and receiver of an encrypted message (and no one else) share the same long string of random digits (the so-called "key") used to encode and decode the message-has always been one of the most important challenges in cryptography. Since the 1980's it's been recognized that the unique properties of quantum mechanics-the fact that certain measurements cannot be made without altering the thing measured-offered the possibility of a system that could transmit as long a key as desired between two parties with no chance that it could be copied undetectably by a third party.

Since then the race has been on to build a fast, practical and reliable QKD system. One important requirement for any candidate system is that it be compatible with existing fiber-optic telecom networks that transmit at wavelengths of either 1550 or 1310 nanometers (nm) to reach the greatest distance. Another requirement is a highly efficient photon detector that can detect single photons reliably without introducing significant amounts of "noise." One of the best low-noise detectors, a silicon-based avalanche photo diode (Si-APD), does not function at the telecom wavelengths. Instead, it operates best at much shorter wavelengths around 700 nm. To take advantage of the Si-APD, the NIST group designed a sub-system to "up-convert" single photons from a transmission wavelength of 1310 nm to 710 nm for high-efficiency detection......... Posted by: Kevin      Read more         Source

June 10, 2007, 7:46 PM CT

Agonized death of dinosaurs

The peculiar pose of a number of fossilized dinosaurs, with wide-open mouth, head thrown back and recurved tail, likely results from the agonized death throes typical of brain damage and asphyxiation, as per two paleontologists.

A classic example of the posture, which has puzzled paleontologists for ages, is the 150 million-year-old Archaeopteryx, the first-known example of a feathered dinosaur and the proposed link between dinosaurs and present-day birds.

"Virtually all articulated specimens of Archaeopteryx are in this posture, exhibiting a classic pose of head thrown back, jaws open, back and tail reflexed backward and limbs contracted," said Kevin Padian, professor of integrative biology and curator in the Museum of Paleontology at the University of California, Berkeley. He and Cynthia Marshall Faux of the Museum of the Rockies published their findings in the recent issue of the quarterly journal Paleobiology, which appeared this week.

Dinosaurs and their relatives, ranging from the flying pterosaurs to Tyrannosaurus rex, as well as a number of early mammals, have been found exhibiting this posture. The explanation commonly given by paleontologists is that the dinosaurs died in water and the currents drifted the bones into that position, or that rigor mortis or drying muscles, tendons and ligaments contorted the limbs......... Posted by: William      Read more         Source