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October 5, 2006, 9:55 PM CT

Plenty Of Carbon Dioxide Storage Capacity

Plenty Of Carbon Dioxide Storage Capacity Carbon dioxide model
As concern has grown over the effects of the human release of carbon dioxide (CO2) gas into the atmosphere, so too has research into technologies to manage CO2. One such research project, overseen by geologist Brandon Nuttall at the Kentucky Geological Survey (KGS) at the University of Kentucky, has investigated the option for geologic sequestration of captured CO2 in Devonian black shales, organic-rich rocks found beneath about two thirds of Kentucky.

Geologic sequestration refers to the process of permanent underground storage of carbon dioxide captured from sources such as coal-fired power plants, cement plants, and others manufacturing plants. Widespread deposits of shale are generally believed to be the seal or cap for deeper storage reservoirs that would prevent sequestered CO2 from leaking to the surface. Injection of CO2 into black gas-producing shales may have an additional value of enhancing the recovery of natural gas.

In the three year project funded by National Energy Technology Laboratory of the U.S. Department of Energy, Nuttall determined that the deeper and thicker parts of the Devonian shales in Kentucky could provide a potentially large geologic storage reservoir for captured CO2. In fact, the extensive occurrence of shales in geologic basins across North America would make them an attractive regional reservoir for economic CO2 sequestration.........

Posted by: Nora      Permalink         Source


October 4, 2006, 10:29 PM CT

Sun Was Born In Star Cluster

Sun Was Born In Star Cluster
The death of a massive nearby star billions of years ago offers evidence the sun was born in a star cluster, say astronomers at the University of Illinois at Urbana-Champaign. Rather than being an only child, the sun could have hundreds or thousands of celestial siblings, now dispersed across the heavens.

In a paper accepted for publication in the Astrophysical Journal, astronomy professors Leslie W. Looney and Brian D. Fields, and undergraduate student John J. Tobin take a close look at short-lived radioactive isotopes once present in primitive meteorites. The researchers' conclusions could reshape current theories on how, when and where planets form around stars.

Short-lived radioactive isotopes are created when massive stars end their lives in spectacular explosions called supernovas. Blown outward, bits of this radioactive material mix with nebular gas and dust in the process of condensing into stars and planets.

When the solar system was forming, some of this material hardened into rocks and later fell to Earth as meteorites.

The radioisotopes have long since vanished from meteorites found on Earth, but they left their signatures in daughter species. By examining the abundances of those daughter species, the scientists could calculate how far away the supernova was, in both distance and time.........

Posted by: Edwin      Permalink         Source


October 4, 2006, 10:21 PM CT

Alaskans Feel The Heat Of Global Warming

Alaskans Feel The Heat Of Global Warming
A new study finds that most Alaskans believe global warming is happening and is a serious threat to the state. The statewide survey, with funding from the National Science Foundation (NSF) and the Center for Research on Environmental Decisions (CRED) at Columbia University, was commissioned by Dr. Anthony Leiserowitz of Decision Research and conducted this summer by the Craciun Research Group.

Jean Craciun, research director for CRG said, "Across the board, no matter what political affiliation or ethnic background, Alaskans are united in their concern about the impacts of global warming".

Highlights of the survey include:
  • Most Alaskans believe global warming is already having major impacts, including the loss of sea ice, melting permafrost, coastal erosion, and forest fires, among other impacts.
  • Many expect that global warming will have dangerous impacts on Alaskans within the next 10 years.
  • Majorities of Alaskans report that global warming is a serious threat to themselves and their families, their local communities, Alaska as a whole, the United States, other countries, and to plants and animals.
  • Most Alaskans support the regulation of greenhouse gas emissions from power plants and the signing of international treaties to reduce emissions, but oppose higher taxes on electricity or gasoline.
........

Posted by: Nora      Permalink         Source


October 4, 2006, 10:09 PM CT

Tree Rings Provide A 200-year-old Hurricane Record

Tree Rings Provide A 200-year-old Hurricane Record
Researchers have shown that an age-old "database"--tree rings--contains surprisingly accurate information about hurricane activity that occurred hundreds of years ago. By measuring different chemical forms of oxygen present in the rings, scientists identified periods when hurricanes hit areas of the Southeast more than 100 years before modern records were kept.

The technique allows researchers to extend from decades to centuries the time-frames of intense hurricane cycles and may help determine if the increase in the number of hurricanes hitting the Southeast since the mid-1990s is part of a regularly occurring cycle or due to causes such as global climate change.

Their research is being reported in the Sept. 18, early online edition of the Proceedings of the National Academy of Sciences. It was funded by grants from the National Science Foundation and the University of Tennessee (UT).........

Posted by: Nora      Permalink         Source


October 4, 2006, 10:06 PM CT

Genome Info From "Plant Destroyers"

Genome Info From
An international team of scientists has published the first two genome sequences from a destructive group of plant pathogens called Phytophthora--a name that literally means "plant destroyer." The more than 80 species of fungus-like Phytophthora (pronounced "fy-TOFF-thor-uh") attack a broad range of plants and together cost the agriculture, forestry and nursery industries hundreds of billions of dollars each year.

Even though Phytophthora are similar to fungi, most fungicides are ineffective at controlling them. The information gained from studying the genomic sequences of P. ramorum and P. sojae will help scientists devise strategies to combat not only these two species, but also other disease-causing Phytophthora.

The study appears in the Sept. 1 issue of the journal Science.

Phytophthora sojae, an endemic pathogen of soybeans, is responsible for $1 billion to $2 billion in losses worldwide each year. Phytophthora ramorum is associated with sudden oak death, a disease that has devastated the nursery industry and oak ecosystems in California, Oregon and Washington. More than 1 million native oak and tanoak trees have been lost to the disease.

In addition to soybean and oak, Phytophthora species cause disease in avocado, coconut, papaya, pineapple, potato, strawberry and watermelon, to name a few. The pathogen also destroys an estimated 450,000 tons of cocoa beans with a resulting $400 million loss in chocolate production each year.........

Posted by: Nora      Permalink         Source


October 4, 2006, 10:02 PM CT

Ice Age Climate-change And Ocean Salinity

Ice Age Climate-change And Ocean Salinity
Sudden decreases in temperature over Greenland and tropical rainfall patterns during the last Ice Age have been linked for the first time to rapid changes in the salinity of the north Atlantic Ocean, as per research published Oct. 5, 2006, in the journal Nature. The results provide further evidence that ocean circulation and chemistry respond to changes in climate.

Using chemical traces in fossil shells of microscopic planktonic life forms, called formanifera, in deep-sea sediment cores, researchers reconstructed a 45,000- to 60,000-year-old record of ocean temperature and salinity. They compared their results to the record of abrupt climate change recorded in ice cores from Greenland. They found the Atlantic got saltier during cold periods, and fresher during warm intervals.

"The freshening likely reflects shifts in rainfall patterns, mostly in the tropics," Howard Spero of the University of California at Davis said. "Suddenly, we're looking at a record that links moisture balance in the tropics to climate change. And the most striking thing is that a measurable transition is happening over decades".

Spero, who is currently on leave at the National Science Foundation's Marine Geology and Geophysics Program, worked with lead author Matthew Schmidt of the Georgia Institute of Technology and Maryline Vautravers of Cambridge University in the United Kingdom to conduct the research.........

Posted by: Nora      Permalink         Source


October 4, 2006, 8:31 PM CT

Earlier Crop Plantings Could Curb Future Yields

Earlier Crop Plantings Could Curb Future Yields
In an ongoing bid to grow more corn, farmers in the U.S. Corn Belt are planting seeds much earlier today than they did 30 years ago, a new study has found.

Poring over three decades of agricultural records, Christopher Kucharik, an associate scientist at the University of Wisconsin-Madison, discovered that farmers in 12 U.S. states now put corn in the ground around two weeks earlier than they did during the late 1970s. His findings are published in the current issue of the Agronomy Journal.

Earlier plantings-which mean longer growing seasons--have likely contributed to the increasing corn yields of recent decades. But Kucharik, a terrestrial ecologist at the UW-Madison's Center for Sustainability and the Global Environment, warns the trend can only continue for so long.

"Earlier plantings really can't continue forever because ultimately, farmers will have to contend with wintertime conditions and frozen soils," says Kucharik. "Several decades from now we might see an unexpected drop in annual yield increases when this trend plateaus, which could then increase the threat to our food supply".

The Corn Belt is a major agricultural region of the U.S. Midwest, where corn is a dominant crop. Centered in Iowa and Illinois, the belt extends into Wisconsin, Michigan, Minnesota, South Dakota, Nebraska, Kansas, Missouri, Indiana, Ohio and Kentucky.........

Posted by: Nora      Permalink         Source


October 4, 2006, 8:15 PM CT

Carbon Nanotubes To Detect Defects In Composites

Carbon Nanotubes To Detect Defects In Composites
Two University of Delaware scientists have discovered a means to detect and identify damage within advanced composite materials by using a network of tiny carbon nanotubes, which act in much the same manner as human nerves.

The discovery has important implications both in the laboratory, where the researchers hope to better predict the life span of various composite materials, and in everyday applications, where it could become an important tool in monitoring the health of composite materials used in the construction of a variety of essential products, including commercial airliners.

The research is the work of Tsu-Wei Chou, Pierre S. du Pont Chair of Engineering, and Erik Thostenson, assistant professor of mechanical engineering, and is featured in an article in the Oct. 2 issue of the influential journal Advanced Materials.

Chou said the research team has been working in the field of fiber composites in conjunction with UD's Center for Composite Materials and of late has taken an interest in the reinforcement of composites with minute nanomaterials--a nanometer is a bare one billionth of one meter--and especially with carbon nanotubes.

"Carbon nanotubes are very small but have superb qualities," Chou said. "They are very light, with a density about one-half that of aluminum, which itself is considered exceptionally light compared to other metals, and yet are 30 times as strong as high-strength steel and as stiff as diamonds".........

Posted by: John      Permalink         Source


October 3, 2006, 10:11 PM CT

Nanoparticles To Aid Brain Imaging

Nanoparticles To Aid Brain Imaging Sensing calcium as it flows into neurons following firing can potentially track information flow throughout the brain's circuitry.
If you want to see precisely what the 10 billion neurons in a person's brain are doing, a good way to start is to track calcium as it flows into neurons when they fire.

To that end, Alan Jasanoff at the McGovern Institute for Brain Research at MIT has developed a new nano-sized calcium-sensing contrast agent that is detectable by magnetic resonance imaging (MRI) scanners, machines that can be used for detailed noninvasive brain imaging.

The work is published in the early online edition of the Proceedings of the National Academy of Sciences the week of Sept. 25-29.

In an application known as functional MRI (fMRI), MRI machines are already increasingly used to observe brain functions as people--or animals--undertake various activities like reading or learning. But Jasanoff notes that current fMRI technology has limitations.

"Using conventional fMRI to study the brain is like trying to understand how a computer works by feeling which parts of it are hot because of energy dissipation in different components," said Jasanoff, who also holds appointments as an assistant professor in MIT's Department of Nuclear Science and Engineering, Department of Brain and Cognitive Sciences, and Biological Engineering Division.

The analogy is apt, because fMRI indirectly measures neural activity by detecting changes in blood flow to brain regions with increased energy requirements. But these hemodynamic changes occur several seconds after the neurons actually fire, too slow to study precise neural activity. Further, the spacing of tiny blood vessels limits the spatial resolution of the technique to volumes containing at least 1,000 neurons, too coarse for discrimination of highly specialized functional areas within a brain region.........

Posted by: John      Permalink         Source


October 3, 2006, 10:07 PM CT

Robot Wheelchair Gives Patients More Independence

Robot Wheelchair Gives Patients More Independence
Engineers at the National Institute of Standards and Technology (NIST) are developing a robotic system that may offer wheelchair-dependent people independent, powered mobility and the ability, depending on patient status, to move to and from beds, chairs and toilets without assistance.*.

The lifting ability of the system, which is called the "HLPR Chair" (for Home Lift, Position and Rehabilitation), also should significantly reduce caregiver and patient injuries.

The HLPR chair draws on mobile robotic technology developed at NIST for defense and manufacturing applications. It is built on an off-the-shelf forklift with a U-frame base on wheel-like casters and a rectangular vertical frame. The frame is small enough to pass through the typical residential bathroom. The user drives the chair using a joystick and other simple controls.

The HLPR chair's drive, steering motors, batteries and control electronics are positioned to keep its center of gravity-even when carrying a patient-within the wheelbase. This allows a person, weighing up to 300 pounds, to rotate out, from the inner chair frame, over a toilet, chair or bed while supported by torso lifts. The torso lifts lower the patient safely into the new position. The chair frame can even remain in position to continue supporting the patient from potential side, back or front fall.........

Posted by: John      Permalink         Source


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