Monday, August 10, 2009

EVIDENCE OF LIQUID WATER IN COMETS REVEALS POSSIBLE ORIGIN OF LIFE

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The watery environment of early comets, together with the vast quantity of organics already discovered in comets, would have provided ideal conditions for primitive bacteria to grow and multiply. So argue Professor Chandra Wickramasinghe and his colleagues at the Cardiff Centre for Astrobiology in a paper published in the International Journal of Astrobiology.

The Cardiff team has calculated the thermal history of comets after they formed from interstellar and interplanetary dust approximately 4.5 billion years ago. The formation of the solar system itself is thought to have been triggered by shock waves that emanated from the explosion of a nearby supernova. The supernova injected radioactive material such as Aluminium-26 into the primordial solar system and some became incorporated in the comets. Professor Chandra Wickramasinghe together with Drs Janaki Wickramasinghe and Max Wallis claim that the heat emitted from radioactivity warms initially frozen material of comets to produce subsurface oceans that persist in a liquid condition for a million years.

Professor Wickramasinghe said: "These calculations, which are more exhaustive than any done before, leaves little doubt that a large fraction of the 100 billion comets in our solar system did indeed have liquid interiors in the past.

Comets in recent times could also liquefy just below their surfaces as they approach the inner solar system in their orbits. Evidence of recent melting has been discovered in recent pictures of comet Tempel 1 taken by the "Deep Impact" probe in 2005."

The existence of liquid water in comets gives added support for a possible connection between life on Earth and comets. The theory, known as cometary panspermia, pioneered by Chandra Wickramasinghe and the late Sir Fred Hoyle argues the case that life was introduced to Earth by comets.

Cardiff Centre for Astrobiology

DISCOVERY ABOUT BEHAVIOR OF BUILDING BLOCK OF NATURE COULD LEAD TO COMPUTER REVOLUTION

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The electron is a fundamental building block of nature and is indivisible in isolation, yet a new experiment has shown that electrons, if crowded into narrow wires, are seen to split apart.

The electron is responsible for carrying electricity in wires and for making magnets. These two properties of magnetism and electric charge are carried by electrons which seem to have no size or shape and are impossible to break apart.

However, what is true about the properties of a single electron does not seem to be the case when electrons are brought together. Instead the like-charged electrons repel each other and need to modify the way they move to avoid getting too close to each other. In ordinary metals this does not usually make much difference to their behaviour. However, if the electrons are put in a very narrow wire the effects are exacerbated as they find it much harder to move past each other.

In 1981, physicist Duncan Haldane conjectured theoretically that under these circumstances and at the lowest temperatures the electrons would always modify the way they behaved so that their magnetism and their charge would separate into two new types of particle called spinons and holons.

The challenge was to confine electrons tightly in a 'quantum wire' and bring this wire close enough to an ordinary metal so that the electrons in that metal could 'jump' by quantum tunneling into the wire. By observing how the rate of jumping varies with an applied magnetic field the experiment reveals how the electron, on entering the quantum wire, has to fall apart into spinons and holons. The conditions to make this work comprised a comb of wires above a flat metal cloud of electrons. The Cambridge physicists, Yodchay Jompol and Chris Ford, clearly saw the distinct signatures of the two new particles as the Birmingham theorists, Tim Silk and Andy Schofield, had predicted.

Dr Chris Ford from the University of Cambridge's Cavendish Laboratory says, 'We had to develop the technology to pass a current between a wire and a sheet only 30 atomic widths apart.

'The measurements have to be made at extremely low temperatures, about a tenth of a degree above absolute zero.

'Quantum wires are widely used to connect up quantum "dots", which may in the future form the basis of a new type of computer, called a quantum computer. Thus understanding their properties may be important for such quantum technologies, as well as helping to develop more complete theories of superconductivity and conduction in solids in general. This could lead to a new computer revolution.'

Professor Andy Schofield from the University of Birmingham's School of Physics and Astronomy says, 'The experiment to test this is based on an idea I had together with three colleagues almost 10 years ago. At that time the technology required to implement the experiment was still a long way off.

'What is remarkable about this new experiment is not just the clarity of the observation of the spinon and holon, which confirms some earlier studies, but that the spinon and holon are seen well beyond the region that Duncan Haldane originally conjectured.

'Our ability to control the behaviour of a single electron is responsible for the semiconductor revolution which has led to cheaper computers, iPods and more. Whether we will be able to control these new particles as successfully as we have the single electron remains to be seen. What it does reveal is that bringing electrons together can lead to new properties and even new particles.'

University of Cambridge

SCIENTISTS UNCORK A POTENTIAL SECRET OF RED WINE'S HEALTH BENEFITS

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Scientists from Scotland and Singapore have unraveled a mystery that has perplexed scientists since red wine was first discovered to have health benefits: how does resveratrol control inflammation?

New research published in the August 2009 print issue of The FASEB Journal (http://www.fasebj.org/), not only explains resveratrol's one-two punch on inflammation, but also show how it—or a derivative—can be used to treat potentially deadly inflammatory disease, such as appendicitis, peritonitis, and systemic sepsis.

"Strong acute inflammatory diseases such as sepsis are very difficult to treat and many die every day due to lack of treatment," said Alirio Melendez, senior lecturer on the faculty of medicine at Glasgow Biomedical Research Centre in Scotland and one of the researchers involved in the work. "Moreover, many survivors of sepsis develop a very low quality of life due to the damage that inflammation causes to several internal organs. The ultimate goal of our study was to identify a potential novel therapy to help in the treatment of strong acute inflammatory diseases."

In this study, researchers administered an inflammatory agent to two groups of mice. One group was pretreated with resveratrol and the other group was not. The mice that were not pretreated with resveratrol experienced a strong inflammatory response, simulating disease in humans, while the group pretreated with resveratrol was protected from the inflammation. The scientists then examined the tissues of the mice to determine exactly how resveratrol was able to protect the mice from inflammation. They found that resveratrol used a one-two punch to stop inflammation in the mice by preventing the body from creating two different molecules known to trigger inflammation, sphingosine kinase and phospholipase D. This finding suggests that resveratrol may be harnessable as a treatment for inflammatory diseases and may also lead to entirely new resveratrol-based drugs that are even more effective.

"The therapeutic potential of red wine has been bottled up for thousands of years," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal, "and now that scientists have uncorked its secrets, they find that studies of how resveratrol works can lead to new treatments for life-threatening inflammation."

The FASEB Journal

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