January 24, 2007, 7:40 PM CT

deep-sea fauna under Antarctic ice shelf

Under the former Larsen ice shelf east of the Antarctic Peninsula, deep-sea sea cucumbers and stalked feather stars were ubiquitously found in shallow waters. These animals usually inhabit far greater water depths.

The main aim of the current Polarstern expedition to Antarctica is the investigation of marine ecosystems under the former Larsen ice shelf. This "white spot" with regard to biodiversity research gave rise to the following questions: What kind of life actually existed under the former floating ice shelf which was up to several hundreds of meters thick? What are the prospects for the future after the collapse of the ice shelf? Obviously, prosperous life did not exist in the area where the Larsen B ice shelf broke off three years ago. This is surprising since Antarctica's seafloor communities are known for their rich assemblages of sessile sponges, cnidarians and moss animals. Instead, underwater video footage and catches of towed sampling gear revealed the dominance of typical deep-sea animals and corresponding life forms.

Here, sea cucumbers and stalked feather stars are the main representatives. These deep-sea inhabitants belong to a group called echinoderms. Until now, stalked feather stars have only been found sporadically and then only below 800m water depths in this sector of Antarctica. But locally in the Larsen B region, they occurred rather frequently at depths of merely 200m. "During my nine expeditions to Antarctica, the only time I have seen the two most abundant species of sea cucumbers was below the far bigger Filchner-Ronne ice shelf further south." This second encounter brought back chief scientist Julian Gutt's memories of his first trip to Antarctica and his PhD thesis 21 years ago. Preliminary results show that a unique macrofauna exists in conjunction with the ice shelf. The sea cucumber Elpidia is probably the most prominent deep-sea animal but is also known to occur in shallow Arctic waters. Maybe this is the reason why this animal is aptly named glacialis (icy) especially with regard to our confirmatory findings on the opposite pole - Antarctica.........

Posted by: Ashley      Read more         Source

January 24, 2007, 6:43 PM CT

Corot Sees First Light!

In the night between 17 and 18 January 2007, the protective cover of the COROT telescope has been successfully opened, and COROT has seen for the first time light coming from stars.

Surveying vast stellar fields to learn about star interiors and to search for extra-solar planets is the goal of this unique mission, whose scientific observations will officially start at the beginning of February this year.

The first light detected by COROT comes from the constellation of the Unicorn near Orion, the great 'hunter' whose imposing silhouette stands out in the winter nights. This nice image, taken during the in-orbit calibration exercise, shows that the quality of this preliminary data is basically as good as the computer simulations. "This is an excellent piece of news," commented Malcolm Fridlund, ESA Project Scientist for COROT.

On 18 January, the telescope was carefully aligned with the region to be observed, facing away from the centre of our Galaxy. This setting that will be maintained until April, when the Sun's rays will start to interfere with the observations.

COROT will then rotate by 180 degrees and will start observing the opposite region towards the centre of the Milky Way. In the meantime the COROT scientists are preparing for the science phase to start in February, continuing a thorough examination of the data and the information collected so far.........

Posted by: Brooke      Read more         Source

January 24, 2007, 6:11 PM CT

First Human Metabalome

Researchers at the University of Alberta, in Edmonton, Canada, have announced the completion of the first draft of the human metabolome, the chemical equivalent of the human genome.

The metabolome is the complete complement of all small molecule chemicals (metabolites) found in or produced by an organism. By analogy, if the genome represents the blueprint of life, the metabolome represents the ingredients of life.

The scientists have catalogued and characterized 2,500 metabolites, 1,200 drugs and 3,500 food components that can be found in the human body.

The research is published in the journal Nucleic Acids Research.

The researchers believe that the results of their work represent the starting point for a new era in diagnosing and detecting diseases.

They believe that the Human Metabolome Project (HMP), which began in Canada in 2004, will have a more immediate impact on medicine and medical practices than the Human Genome Project, because the metabolome is far more sensitive to the body's health and physiology.

"Metabolites are the canaries of the genome," says Project Leader Dr. Wishart, professor of computing science and biological sciences at the University of Alberta and Principal Investigator at NRC, National Institute for Nanotechnology. "A single base change in our DNA can lead to a 100,000X change in metabolite levels".........

Posted by: Sean      Read more         Source

January 24, 2007, 5:29 PM CT

Step Toward Building Molecular Computers

A team of UCLA and California Institute of Technology chemists reports in the Jan. 25 issue of the journal Nature the successful demonstration of a large-scale, "ultra-dense" memory device that stores information using reconfigurable molecular switches. This research represents an important step toward the creation of molecular computers that are much smaller and could be more powerful than today's silicon-based computers.

The 160-kilobit memory device uses interlocked molecules manufactured in the UCLA laboratory of J. Fraser Stoddart, director of the California NanoSystems Institute (CNSI), who holds UCLA's Fred Kavli Chair in Nanosystems Sciences and who was awarded a knighthood by Queen Elizabeth II less than a month ago.

A bit, or binary digit, is the basic unit of information storage and communication in digital computing. A kilobit is equal to 1,000 bits and is commonly used for measuring the amount of data that is transferred in one second between two telecommunication points.

The research published in Nature describes the fabrication and operation of a memory device. The memory is based on a series of perpendicular, crossing nanowires, similar to a tic-tac-toe board, with 400 bottom wires and another 400 crossing top wires. Sitting at each crossing of the tic-tac-toe structure and serving as the storage element are approximately 300 bistable rotaxane molecules. These molecules may be switched between two different states, and each junction of a crossbar can be addressed individually by controlling the voltages applied to the appropriate top and bottom crossing wires, forming a bit at each nanowire crossing.........

Posted by: Kevin      Read more         Source

January 17, 2007, 8:15 PM CT

Obstacle From Mass Production Of Tiny Circuits Removed

As they eliminate tiny air bubbles that form when liquid droplets are molded into intricate circuits, a Princeton-led team is dissolving a sizable obstacle to the mass production of smaller, cheaper microchips.

Led by Stephen Chou, the Joseph C. Elgin Professor of Engineering at Princeton, the team worked to troubleshoot one form of nanoimprint lithography, a revolutionary method invented by Chou in the 1990s. Nanoimprint uses a nanometer-scale mold to pattern computer chips and other nanostructures, and is in marked contrast to conventional methods that use beams of light, electrons or ions to carve designs onto devices.

This technique allows for the creation of circuits and devices with features that are not much longer than a billionth of a meter, or nanometer -- more than 10 times smaller than is possible in today's mass-produced chips, yet more than 10 times cheaper. Because of its unique capabilities and reasonable cost, nanoimprinting is a key solution to the future manufacturing of computer chips and a broad range of nanodevices for use in optics, magnetic data storage and biotechnology, among other disciplines.

In dispensing-based nanoimprinting, liquid droplets on the surface of a silicon wafer are pressed into a pattern, which quickly hardens to form the desired circuitry. This technique is more attractive to manufacturers than some other forms of nanoimprinting because it does not need to be done in an expensive vacuum chamber. However, the widespread use of the technique has been hindered by the formation of gas bubbles that distort the intended pattern.........

Posted by: Kevin      Read more         Source

January 15, 2007, 9:27 PM CT

Molecular Differences Between Rice And Its Mimic

Red rice sounds like a New Orleans dish or a San Francisco treat. But it's a weed, the biggest nuisance to American rice growers, who are the fourth largest exporters of rice in the world. And rice farmers hate the pest, which, if harvested along with domesticated rice, reduces marketability and contaminates seed stocks.

Complicating matters is the fact that red rice and cultivated rice are exactly the same species, so an herbicide cannot be developed that seeks out only red rice. It would kill cultivated rice, too.

But now a plant evolutionary biologist at Washington University in St. Louis has been funded by the National Science Foundation (NSF) at $1.12 million for two years to perform genetic studies on red rice to understand molecular differences between the two that someday could provide the basis for a plan to eradicate the weed. The particular NSF program funding the research is the Plant Genome Comparative Sequencing Program.

Kenneth M. Olsen, Ph.D., Washington University assistant professor of biology in Arts & Sciences, believes that gene flow is one factor that has been at work.

"We are looking for candidate genes that underlie particular traits that differ between the two," said Olsen. "Knowing more about the traits could help in potentially controlling the weed. We have a key advantage in this research in that we know the complete cultivated rice genome, so it's fairly easy to target genes of interest."........

Posted by: Jessica      Read more         Source

January 15, 2007, 7:32 PM CT

Rubus thibetanus 'Silver Fern'

This bramble is the source of much recent photographic frustration for me. It beckons outside my second-floor office window with its tangled icy-blue mass of canes, asking to be photographed in pretty much the exact frame that I see through the window from my office chair - a window that only opens thirty degrees outwards, thereby requiring me to either 1) move furniture and lean out the window while undergoing unnatural contortions (which I suspect the safety folks might have something to say about); 2) take the photograph through the window glass (and accept some glare and reduced image quality); or 3) let it taunt me. I wonder if I can get away with propping a ladder against the side of the building.

This shot was from a much closer distance, with a new lens.

By Daniel Mosquin.........

Posted by: Jessica      Read more         Source

January 15, 2007, 7:21 PM CT

A Year Of Extraterrestrial Fountains And Flows

The past year was extraordinary for the discovery of extraterrestrial fountains and flows -- some offering new potential in the search for liquid water and the origin of life beyond planet Earth. Increased evidence was uncovered that fountains spurt not only from Saturn's moon Enceladus, but from the dunes of Mars as well. Lakes were found on Saturn's moon Titan, and the residual of a flowing liquid was discovered on the walls of Martian craters.

The diverse Solar System fluidity may involve forms of slushy water-ice, methane, or sublimating carbon dioxide. Pictured above, the light-colored path below the image center is hypothesized to have been created sometime in just the past few years by liquid water flowing across the surface of Mars.........

Posted by: Brooke      Read more

January 15, 2007, 5:19 AM CT

Hofmeyr-Skull supports the "Out of Africa"-Theory

Reliably dated fossils are critical to understanding the course of human evolution. A human skull discovered over fifty years ago near the town of Hofmeyr, in the Eastern Cape Province of South Africa, is one such fossil. A study by an international team of researchers led by Frederick Grine of the Departments of Anthropology and Anatomical Sciences at Stony Brook University in New York published recently in Science magazine has dated the skull to 36,000 years ago. This skull provides critical corroboration of genetic evidence indicating that modern humans originated in sub-Saharan Africa and migrated about this time to colonize the Old World. (Science January 12, 2007).

"The Hofmeyr skull gives us the first insights into the morphology of such a sub-Saharan African population, which means the most recent common ancestor of all of us - wherever we come from," said Grine.

Eventhough the skull was found over half a century ago, its significance became apparent only recently. A new approach to dating developed by Grine team member Richard Bailey and colleagues at Oxford University allowed them to determined its age at just over 36,000 years ago by measuring the amount of radiation that had been absorbed by sand grains that filled the inside of the skull's braincase. At this age, the skull fills a significant void in the human fossil record of sub-Saharan Africa from the period between about 70,000 and 15,000 years ago. During this critical period, the archaeological tradition known as the Later Stone Age, with its sophisticated stone and bone tools and artwork appears in sub-Saharan Africa, and anatomically modern people appear for the first time in Europe and western Asia with the equally complex Upper Paleolithic archeological tradition.........

Posted by: William      Read more         Source

January 15, 2007, 5:12 AM CT

One In Four Specialist Trainee Doctors 'Very Worried'

One in four specialist trainee doctors in England views their future job prospects as "poor" or "very worrying," as a result of changes in training and healthcare delivery, reveals a survey* published ahead of print in a special edition of Postgraduate Medical Journal.

While the government plans to shift the focus of care, particularly for long term conditions, away from hospitals into the community, almost a third of those surveyed regarded working with patients directly in these settings as a "bad" or "very bad" development, the responses reveal.

Eight out of 10 respondents felt poorly prepared to meet the challenge of working as specialist practitioners in the community, and wanted additional training to enable them to work in the new environment.

Three out of four felt that this should take the form of a university based degree. But even with appropriate training, only half felt that they would be better equipped to find work as a consultant.

The study authors point out that by 2010, the number of medical graduates will have increased by 50%.

Coupled with the shift of emphasis to healthcare provision in community based facilities, and a much greater focus on prevention, this will create new responsibilities for doctors and drastically cut the number of hospital based specialists required, they say.........

Posted by: Sean      Read more         Source