July 19, 2007, 10:09 PM CT

Number of published science and engineering articles flattens

Number of published U.S. science and technology articles plateaued in the 1990s, despite continued increases in funding and personnel for research and development.

A new National Science Foundation (NSF) report finds the number of U.S. science and engineering (S&E) articles in major peer-evaluated journals flattened in the 1990s, after more than two decades of growth, but U.S. influence in world science and technology remains strong.

The report, Changing U.S. Output of Scientific Articles: 1988 - 2003, finds changes occurred despite continued increases in funding and personnel for research and development. Flattening occurred in nearly all U.S. research disciplines and types of institutions.

In contrast, emerging Asian nations had large increases in publication numbers, reflecting their growing expertise in science and technology. European Union totals also went up.

Numbers of articles published and their citation in S&E journals is a widely accepted indicator of research capability. When paired with trends in patenting, licensing, research and development expenditures and advanced training of personnel, publication trends may be viewed as a factor affecting a nation's ability to spur technological innovation.

Despite the leveling of articles published, scientists emphasize other evidence that indicates U.S. science and technology capability remains strong. They say the change in U.S. share of the world's S&E articles is not a surprise in view of growing S&E research capability around the world, nor do they view it as a cause for concern......... Posted by: Jaison      Read more         Source

July 17, 2007, 10:21 PM CT

Natural 'workbench' For Nanoscale Construction

Engineers at the University of Pennsylvania have taken a step toward simplifying the creation of nanostructures by identifying the first inorganic material to phase separate with near-perfect order at the nanometer scale. The finding provides an atomically tuneable nanocomposite workbench that is cheap and easy to produce and provides a super-lattice foundation potentially suitable for building nanostructures.

The findings are reported in the recent issue of Nature Materials.

Alerted by an unusual diffraction effect of a common ceramic material, scientists used imaging to identify a two-phase structural pattern ideal as the first step towards nanodevice construction. Practical application of nanotechnology will rely upon engineerings ability to manipulate atoms and molecules into long-range order to produce materials with desired functionalities. The Penn findings provide a simpler method for the ordering of composite parts on the nanometer scale, which is integral to the incorporation of nano-objects such as particles and wires that make up nanodevices.

The material used in the Penn study is an ionically- conductive, crystalline ceramic (Nd2/3-xLi3x)TiO3 that engineers observed with transmission electron microscopy. The powdered perovskite exhibited two distinct patterns at the atomic scale with identical periodicity: a nanoscale chessboard pattern and a diamond pattern that indicated periodic separation into two phases within the structure. This spontaneous separation of phases could present a new foundation on which to build nanodevice technology. This material made using standard and easily reproducible ceramic processing methods represents the formation of a spontaneous microscopic surface controlled on the nanoscale with atomic precision......... Posted by: Kevin      Read more         Source

July 12, 2007, 10:58 PM CT

Breath Of Volcano

Indonesia's Mount Gamkonora volcano is spewing hot ash and smoke into the air, as seen in this image taken by the MERIS instrument aboard ESA's satellite Envisat, causing more than 8000 people to be evacuated amid fears of an imminent eruption, as per officials.

Officials raised the alert to the highest level on Tuesday after the volcano, located in the eastern province of North Maluku, started spitting out flaming material, indicating magma was approaching the crater's surface making an eruption more likely, Saut Simatupang of Indonesia's Vulcanological Survey told Reuters news agency.

The 1635m volcano, located about 2400 km northeast of Jakarta, began releasing smoke and ash on Saturday and spewed it as high as 4000m on Monday. Mount Gamkonora is the highest peak on Halmahera Island.

Indonesia is located within the Pacific 'Ring of Fire', a continuous line (40 000 km long) of volcanoes and fault lines circling the edges of the Pacific Ocean, and has more than a hundred active volcanoes within its territory.

The majority of the 1500 active volcanoes on the Earth's surface, of which around 50 erupt each year, are located along the Pacific 'Ring of Fire'. At least 500 million people live close to an active volcano.

As world population increases, so does the potential threat from every eruption. Eventhough there is no way ground-based monitoring can be carried out on all volcanoes across the globe, space-based monitoring helps identify the volcanoes presenting the greatest danger......... Posted by: Tyler      Read more         Source

July 12, 2007, 8:28 PM CT

Masses of methane escape from Italy

Italy is the seventh largest European producer of natural gas, with reservoir volumes approaching 2200 billion cubic meters (2877 billion cubic yards). Of this, 74 percent formed through microbial decay of organic matter (biogenic gas), 14 percent formed by thermal breakdown of organic material at greater depth (thermogenic), and 12 percent is mixed. Because most gas fields occur in areas influenced by tectonics, gas migration to the surface is widespread, leading to over a thousand seeps, including mud volcanoes and dry seeps.

Etiope et al. assess the gas origin from all main seeps still active today. Noting that methane is a potent greenhouse gas, they seek to quantify its flux to the atmosphere, including contributions from diffuse soil degassing. They find that 80 percent of the seeps release thermogenic gas, and that mud volcano gas is generally lighter (more methane, less ethane and propane) than its original reservoir gas. Dry seeps, instead, maintain the same alkane composition as their reservoirs. The authors estimate that methane emission may reach levels of hundreds of thousands tons per year, comparable to national emissions from the fossil fuel industry......... Posted by: Sarah      Read more         Source

July 12, 2007, 8:06 PM CT

Fragmented Structure of Seafloor

A number of earthquakes in the deep ocean are much smaller in magnitude than expected. Geophysicists from the Woods Hole Oceanographic Institution (WHOI) have found new evidence that the fragmented structure of seafloor faults, along with previously unrecognized volcanic activity, may be dampening the effects of these quakes.

Examining data from 19 locations in the Atlantic, Pacific, and Indian oceans, scientists led by graduate student Patricia Gregg have observed that "transform" faults are not developing or behaving as theories of plate tectonics say they should. Rather than stretching as long, continuous fault lines across the seafloor, the faults are often segmented and show signs of recent or ongoing volcanism. Both phenomena appear to prevent earthquakes from spreading across the seafloor, thus reducing their magnitude and impact.

Gregg, a doctoral candidate in the MIT/WHOI Joint Program in Oceanography and Oceanographic Engineering, conducted the study with seismologist Jian Lin and geophysicists Mark Behn and Laurent Montesi, all from the WHOI Department of Geology and Geophysics. Their findings were reported in the July 12 issue of the journal Nature.

Oceanic transform faults cut across the mid-ocean ridge system, the 40,000-mile-long mountainous seam in Earth's crust that marks the edges of the planet's tectonic plates. Along some plate boundaries, such as the Mid-Atlantic Ridge, new crust is formed. In other regions, such as the western Pacific, old crust is driven back down into the Earth......... Posted by: Tyler      Read more         Source

July 12, 2007, 8:03 PM CT

Speed bumps less important than potholes for graphene

For electrical charges racing through an atom-thick sheet of graphene, occasional hills and valleys are no big deal, but the potholessingle-atom defects in the crystaltheyre killers. Thats one of the conclusions reached by scientists from the National Institute of Standards and Technology (NIST) and the Georgia Institute of Technology who created detailed maps of electron interference patterns in graphene to understand how defects in the two-dimensional carbon crystal affect charge flow through the material. The results, appearing in the July 13 issue of Science*, have implications for the design of graphene-based nanoelectronics.

A single layer of carbon atoms tightly arranged in a honeycomb pattern, graphene was long believed to be an interesting theoretical concept that was impossible in practiceit would be too unstable, and crumple into some other configuration. The discovery, in 2004, that graphene actually could exist touched off a rush of experimentation to explore its properties. Graphene has been described as a carbon nanotube unrolled, and shares some of the unique properties of nanotubes. In particular, its a so-called ballistic conductor, meaning that electrons flow through it at high speed, like photons through a vacuum, with virtually no collisions with the atoms in the crystal. This makes it a potentially outstanding conductor for wires and other elements in nanoscale electronics......... Posted by: Sarah      Read more         Source

July 10, 2007, 5:27 AM CT

Invisible gases form most organic haze in urban, rural areas

A new study involving the University of Colorado at Boulder shows that invisible, reactive gases hovering over Earth's surface, not direct emissions of particulates, form the bulk of organic haze in both urban and rural areas around the world.

A number of science and health professionals have believed sources that spew soot and other tiny particles directly into the air were the primary culprit in the formation of organic haze. But a new study by scientists at CU-Boulder's Cooperative Institute for Research in Environmental Sciences show aerosols formed chemically in the air account for about two-thirds of the total organic haze in urban areas and more than 90 percent of organic haze in rural areas.

The study was led by Qi Zhang, a former CIRES scientist now at the Atmospheric Sciences Research Center at State University of New York, Albany and CIRES researcher Jose-Luis Jimenez. The study was reported in the July 7 online issue of Geophysical Research Letters.

The researchers compared concentrations of directly emitted, or primary, aerosols with chemically formed, or secondary aerosols. They surveyed urban areas, areas downwind of urban areas and rural areas from 37 sites in 11 countries.

"What we're seeing is that concentrations of secondary organic aerosols decrease little downwind from urban areas," said Jimenez, also an assistant professor in CU-Boulder's chemistry and biochemistry department. "That tells us there has to be an extended source or continuous formation for the pollution"......... Posted by: Sarah      Read more         Source

July 8, 2007, 10:24 PM CT

Life elsewhere in Solar System

The search for life elsewhere in the solar system and beyond should include efforts to detect what researchers sometimes refer to as "weird" life -- that is, life with an alternative biochemistry to that of life on Earth -- says a new report from the National Research Council. The committee that wrote the report observed that the fundamental requirements for life as we generally know it -- a liquid water biosolvent, carbon-based metabolism, molecular system capable of evolution, and the ability to exchange energy with the environment -- are not the only ways to support phenomena recognized as life. "Our investigation made clear that life is possible in forms different than those on Earth," said committee chair John Baross, professor of oceanography at the University of Washington, Seattle.

The report emphasizes that "no discovery that we can make in our exploration of the solar system would have greater impact on our view of our position in the cosmos, or be more inspiring, than the discovery of an alien life form, even a primitive one. At the same time, it is clear that nothing would be more tragic in the American exploration of space than to encounter alien life without recognizing it".

The tacit assumption that alien life would utilize the same biochemical architecture as life on Earth does means that researchers have artificially limited the scope of their thinking as to where extraterrestrial life might be found, the report says. The assumption that life requires water, for example, has limited thinking about likely habitats on Mars to those places where liquid water is believed to be present or have once flowed, such as the deep subsurface. However, as per the committee, liquids such as ammonia or formamide could also work as biosolvents -- liquids that dissolve substances within an organism -- albeit through a different biochemistry. The recent evidence that liquid water-ammonia mixtures may exist in the interior of Saturn's moon Titan suggests that increased priority be given to a follow-on mission to probe Titan, a locale the committee considers the solar system's most likely home for weird life......... Posted by: Jaison      Read more         Source

July 5, 2007, 9:41 PM CT

The Earth is smaller than assumed

Eventhough the discrepancy is not large, it is significant: Geodesists from the University of Bonn have remeasured the size of the Earth in a long lasting international cooperation project. The blue planet is accordingly some millimeters smaller than up to now assumed. The results are important, for example, to be able to demonstrate a climate contingent rise in sea level. The results have now appeared in the renowned Journal of Geodesy.

The system of measurement used by the Bonn Geodesists is invisible. It consists of radiowaves that are transmitted into space from punctiform sources, the so-called Quasars. A network of more than 70 radio telescopes worldwide receives these waves. Because the gaging stations are so far apart from each other, the radio signals are received with a slight time-lag. From this difference we can measure the distance betwen the radio telescopesand to the preciseness of two millimeters per 1,000 kilometers, explained Dr. Axel Nothnagel, reasearch group leader for the Geodesy Institute of the University of Bonn.

The procedure is called VLBI, which stands for Very Long Baseline Interferometry. The technique can be used, for example, to demonstrate that Europe and North America are distancing from each other at a rate of about 18 millimeters annually. The distance of the gaging stations from each other allows the the size of the Earth or the exact location of the center of the Earth to be determined. We have analyzed the measurements and calculations from 34 partners in 17 countries, explained Nothnagel. A combination of GPS and satellite laser measurements will enable the availability of the coordinates from almost 400 points on the surface of the Earth with unparalleled exactness......... Posted by: Tyler      Read more         Source

July 5, 2007, 9:10 PM CT

Coaching Computer Canines

The mutts are metal, the size of toy poodles, with four pointy feet ending in little balls. They need to learn how to make their way on those little feet across a treacherous terrain of broken rocks. University of Southern California roboticist Stefan Schaal has just won renewal of a $1.5 million DARPA contract to train them to do so.

Schaal, an associate professor in the USC Viterbi School of Engineering department of computer science, began working on the problem more than a year ago.

Four- and six-legged robots have been walking around for years, he noted - but most just on smooth surfaces where wheels are a more efficient of getting around.

"What you really want legged robots for is to negotiate difficult terrain," he says. " This project is designed to push that envelop".

Boston Dynamics builds the 'bots, which come with an onboard computer chip connected to sensors.

The robot is continually aware of the location of its center of gravity.The strategy for walking, as explained in a paper Schaal presented at the 2007 IEEE International Conference on Robotics and Automation, was "to adjust a smooth walking pattern generator with the selection of every foot placement such that the center of gravity. follows a stable trajectory"......... Posted by: Kevin      Read more         Source