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October 26, 2006, 4:48 AM CT

World's Most Intense Thunderstorms

World's Most Intense Thunderstorms A snapshot of the worldwide inventory of thunderstorms from NASA's Tropical Rainfall Measuring Mission shows storms over Texas on April 30, 2004
A summer thunderstorm often provides much-needed rainfall and heat wave relief, but others bring large hail, destructive winds, and tornadoes. Now with the help of NASA satellite data, scientists are gaining insight into the distribution of such storms around much of the world.

By using data from the NASA Tropical Rainfall Measuring Mission (TRMM) satellite, researchers identified the regions on Earth that experience the most intense thunderstorms. Their study was published in the August 2006 issue of the Bulletin of the American Meteorological Society. The strongest storms were found to occur east of the Andes Mountains in Argentina, where warm, humid air often collides with cooler, drier air, similar to storms that form east of the Rockies in the United States. Surprisingly, some semi-arid regions have powerful storms, including the southern fringes of the Sahara, northern Australia, and parts of the Indian subcontinent. In contrast, rainy areas such as western Amazonia and Southeast Asia experience frequent storms, but relatively few are severe. Northern Pakistan, Bangladesh, and parts of Central Africa also experience intense thunderstorms.

"TRMM has given us the ability to extend local knowledge about storms to a near-global reach," said lead author Edward Zipser, University of Utah, Salt Lake City. "In addition to containing the only precipitation radar in space, TRMM's other instruments provide a powerful overlap of data that is extremely useful for studying storms".........

Posted by: Nora      Permalink         Source


October 25, 2006, 5:03 AM CT

The Space Tourism Industry Can Really Make Money

The Space Tourism Industry Can Really Make Money
So far, only one craft has flown in space, sending test pilots to the final frontier at an expense of $25 million-plus to win the $10 million Ansari X Prize. Market right now doesn't show the prospects that were expected by the investors in the space tourism industry.

But this doesn't mean that people in the real world don't have any respect for this industry. Space Tourism is not aimed at "space geeks" only. This seems the way it is because people in the real world can't afford the million dollars ride into the space and it looks like they are less bothered about what is going on in the space tourism industry.

Every body around the world would like to see the futuristic industry to succeed in the splendid mission they are trying to achieve. The market will sooner prove that investors can really make money on space tourism. There are no doubt high risks in investing millions or billions of dollars. But all of this is going to come out in its totality in two to four years.

Via:msnbc........

Posted by: Edwin      Permalink         Source


October 24, 2006, 8:31 PM CT

Direct Proof Of Stellar Sorting In A Globular Cluster

Direct Proof Of Stellar Sorting In A Globular Cluster
A seven year study with the NASA/ESA Hubble Space Telescope has provided astronomers with the best observational evidence yet that globular clusters sort out stars according to their mass, governed by a gravitational billiard ball game between stars. Heavier stars slow down and sink to the cluster's core, while lighter stars pick up speed and move across the cluster to its periphery. This process, called "mass segregation", has long been suspected for globular star clusters, but has never before been directly seen in action.

Imagine trying to understand how a football game works based on just a few fuzzy snapshots of the game in play. This is the just the kind of challenge faced by astronomers trying to understand the dynamics of the swarm of stars in the globular star clusters that orbit our Milky Way Galaxy. The NASA/ESA Hubble Space Telescope has provided the best observational evidence to date that globular clusters sort stars according to their mass, governed by a gravitational billiard ball game between stars. Heavier stars slow down and sink to the cluster's core, while lighter stars pick up speed and move out across the cluster to its periphery. This process, called mass segregation, has long been suspected for globular star clusters, but has never been seen in action directly before.........

Posted by: Edwin      Permalink         Source


October 24, 2006, 8:19 PM CT

Amazon River Reversed Flow

Amazon River Reversed Flow
Ask any South American dinosaur which way the Amazon River flows and she would have told you east-to-west, the opposite of today. That's the surprising conclusion of researchers studying ancient mineral grains buried in the Amazon Basin.

The once westward roll of what is now the world's largest river was caused by a long-gone highland near what today is the river's mouth. That highland was created by the breaking away of South America from Africa and the creation of the Atlantic Ocean during the Cretaceous Period, 65 to 145 million years ago. Later, when the Andes rose up on the western side of South America, the river had no choice but to drain into the new ocean.

"It just happened in a way that the current Amazon could take advantage of where an old river and ocean basin used to sit," said geologist Russell Mapes, a doctoral candidate at the University of North Carolina in Chapel Hill.

Previous Brazilian and U.S. researchers have proposed smaller scale reversals and splits in the Amazon Basin, but nothing on the scale of the entire basin, said Mapes.

The evidence for the Amazon's ancient switcheroo comes in the form of tiny crystals of a mineral called zircon, as well as telltale signs of the river flow direction captured in the structure of old river sediments.........

Posted by: Nora      Permalink         Source


October 24, 2006, 6:08 PM CT

Electronic Chip Interacting With The Brain

Electronic Chip Interacting With The Brain
Researchers at the University of Washington (UW) are working on an implantable electronic chip that may help establish new nerve connections in the part of the brain that controls movement. Their most recent study, would be published in the Nov. 2, 2006, edition of Nature, showed such a device can induce brain changes in monkeys lasting more than a week. Strengthening of weak connections through this mechanism may have potential in the rehabilitation of patients with brain injuries, stroke, or paralysis.

The authors of study, titled "Long-Term Motor Cortex Plasticity Induced by an Electronic Neural Implant," were Dr. Andrew Jackson, senior research fellow in physiology and biophysics, Dr. Jaideep Mavoori, who recently earned a Ph.D. in electrical engineering from the UW, and Dr. Eberhard Fetz, professor of physiology and biophysics. For many years Fetz and his colleagues have studied how the brains of monkeys control their limb muscles.

When awake, the brain continuously governs the body's voluntary movements. This is largely done through the activity of nerve cells in the part of the brain called the motor cortex. These nerve cells, or neurons, send signals down to the spinal cord to control the contraction of certain muscles, like those in the arms and legs.........

Posted by: John      Permalink         Source


October 22, 2006, 8:20 PM CT

Newton's Apple Tree Bears Fruit

Newton's Apple Tree Bears Fruit The descendant of Isaac Newton's tree continues to produce apples.
Photo / Donna Coveney
Ed Vetter (S.B. 1942) gave MIT an apple tree that is a direct descendant of the tree under which Isaac Newton sat when he is said to have conceived the theory of gravity.

"I couldn't think of a better place than MIT to put a tree that illustrates a law of physics," says Vetter, whose tree stands in MIT's President's Garden, a sunny spot off the Infinite Corridor.

This fall, the beloved tree bore bright, healthy fruit--a sure sign of flourishing and a link between past and present days.

The MIT apple tree was grown from a cutting of a tree in England's Royal Botanical Gardens that was grown from a cutting of Newton's apple tree. Vetter was given the plant as a gift from the National Bureau of Standards when he left office as undersecretary of the U.S. Commerce Department in 1977. He presented the young plant to MIT that same year.

"I'll be honest with you, whenever I'm at MIT I always stop to see how the tree is doing," he says. "I've watched it grow from eight inches to 12 feet. It makes me feel good to know that it has flourished and that people enjoy it".

It is a fact, he says, that over the years the tree has become the apple of his eye.........

Posted by: Nora      Permalink         Source


October 22, 2006, 7:50 PM CT

Molecular Spintronic Action In Nanostructure

Molecular Spintronic Action In Nanostructure NIST researchers made the first confirmed "spintronic" device incorporating organic molecules using a nanoscale pore test structure.
Scientists at the National Institute of Standards and Technology (NIST) have made the first confirmed "spintronic" device incorporating organic molecules, a potentially superior approach for innovative electronics that rely on the spin, and associated magnetic orientation, of electrons. The physicists created a nanoscale test structure to obtain clear evidence of the presence and action of specific molecules and magnetic switching behavior.

Whereas conventional electronic devices depend on the movement of electrons and their charge, spintronics works with changes in magnetic orientation caused by changes in electron spin (imagine electrons as tiny bar magnets whose poles are rotated up and down). Already used in read-heads for computer hard disks, spintronics can offer more desirable properties-higher speeds, smaller size-than conventional electronics. Spintronic devices commonly are made of inorganic materials. The use of organic molecules may be preferable, because electron spins can be preserved for longer time periods and distances, and because these molecules can be easily manipulated and self-assembled. However, until now, there has been no experimental confirmation of the presence of molecules in a spintronic structure. The new NIST results are expected to assist in the development of practical molecular spintronic devices.........

Posted by: John      Permalink         Source


October 22, 2006, 7:40 PM CT

New Standard For Semiconductor Industry

New Standard For Semiconductor Industry
A wide range of optical electronic devices, from laser disk players to traffic lights, may be improved in the future thanks to a small piece of semiconductor, about the size of a button, coated with aluminum, gallium, and arsenic (AlGaAs).

The 1-centimeter square coating, just 3 micrometers thick, is the first standard for the chemical composition of thin-film semiconductor alloys issued by the National Institute of Standards and Technology (NIST). Standard Reference Material (SRM) 2841 was requested by the compound semiconductor industry to help measure and control thin film composition as a basis for optimizing material and device properties. The SRM can be used to calibrate equipment for making or analyzing these materials. Buyers are expected to include companies that grow or characterize thin films or use them to make devices, as well as government and university laboratories.

AlGaAs is used as a barrier material to increase conductivity in high-speed circuits for wireless communication; semiconductor lasers for optical disk drives, bar code scanning, xerography, and laser surgery; and light-emitting diodes for remote controls, traffic lights, and medical instruments. The NIST standard is expected to increase the accuracy of chemical characterization of AlGaAs films by an order of magnitude over the current state of the art. Improved accuracy will reduce wasteful duplication of reference wafers, increase the free exchange of thin-film materials between vendors and their customers, and ultimately improve the accuracy of data on relationships between material composition and properties.........

Posted by: John      Permalink         Source


October 19, 2006, 9:08 PM CT

Hyper-Cest MRI And Molecular Imaging

Hyper-Cest MRI And Molecular Imaging Two-compartment phantom is a diagram of how HYPER-CEST works
Scientists with the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California at Berkeley have developed a new technique for Magnetic Resonance Imaging (MRI) that allows detection of signals from molecules present at 10,000 times lower concentrations than conventional MRI techniques. Called HYPER-CEST, for hyperpolarized xenon chemical exchange saturation transfer, this new technique holds great promise for molecular imaging, in which the spatial distribution of specific molecules is detected within an organism. Ultimately, HYPER-CEST could become a valuable tool for medical diagnosis, including the early detection of cancer.

In a paper reported in the October 20, 2006 issue of the journal Science, the team of scientists report on a technique in which xenon atoms that have been hyperpolarized with laser light to enhance their MRI signal, incorporated into a biosensor and associated with specific protein or ligand targets. These hyperpolarized xenon biosensors generate highly selective contrast at sites where they are bound, dramatically boosting the strength of the MRI signal and resulting in spatial images of the chosen molecular or cellular target.

This research was led by Alexander Pines and David Wemmer, who both hold joint appointments with Berkeley Lab and UC Berkeley. Their paper is entitled Molecular Imaging Using a Targeted Magnetic Resonance Hyperpolarized Biosensor. Co-authoring the paper with Pines and Wemmer were Leif Schroder and Thomas Lowery, plus Christian Hilty.........

Posted by: John      Permalink         Source


October 18, 2006, 8:41 PM CT

National Center for X-ray Tomography

National Center for X-ray Tomography The new soft x-ray microscope at the National Center for X-ray Tomography captured its first x-rays on August 23, 2006
The National Center for X-ray Tomography (NCXT) has officially been dedicated at the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab). Located at Berkeley Lab's Advanced Light Source (ALS), this new center features a first-of-its-kind x-ray microscope that will enable researchers to perform "Computerized axial tomography scans" on biological cells, just one of a number of unprecedented capabilities for cell and molecular biology studies.

"X-ray microscopy is an emerging new technology that expands the imaging toolbox for cell and molecular biologists, and we are going to make this technology available to the greater biological community," said cell biologist and microscopy expert Carolyn Larabell, who is the principal investigator for the new center. Larabell, holds a joint appointment with Berkeley Lab's Physical Biosciences Division and the Anatomy Department of UC San Francisco. Her co-principal investigator at the center is.

Berkeley Lab physicist Mark Le Gros.

The NCXT is being funded with grants from the U.S. Department of Energy (DOE) and from the National Institutes of Health (NIH). For construction and five years of operation, the Biological and Environmental Research (BER) program in DOE's Office of Science has provided about $7 million. NIH has provided about $5 million through its National Center for Research Resources program, which establishes "biomedical technology resource centers," such as the NCXT, to provide researchers and clinical scientists with "the environments and tools they need to understand, detect, treat, and prevent a wide range of diseases."........

Posted by: John      Permalink         Source


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