Stories of Modern Science ... from UPI

LARGEST ANTARCTIC ICE SHELF BREAK

The largest iceberg in 30 years has broken off from the northern section of the Larsen B ice sheet on the eastern side of the Antarctic Peninsula, according to the National Snow and Ice Data Center at the University of Colorado at Boulder. "This breakup gave us the information we need to reassess the stability of ice shelves around the rest of the Antarctic continent," says glaciologist Ted Scambos. "They are closer to the limit than we thought." The shattered ice has formed a plume of thousands of icebergs adrift in the Weddell Sea, east of the Antarctic Peninsula. A total of about 1,250 square miles of shelf area has disintegrated in a 35-day period beginning on Jan. 31 of this year. Over the last five years, the Larsen B shelf has lost a total of 2,200 square miles -- and is now about 40 percent the size of its previous minimum stable extent. Scientists attribute the breaks to strong regional climate warming.

POSSIBLE NEW SUPERCONDUCTOR

A potential new high-temperature superconductor has been identified by physicists at the University of California at Davis. Calculations by Helge Rosner, Alexander Kitaigorodsky and Warren Pickett predict that lithium borocarbide should have essentially no resistance to electrical current at temperatures up to minus 280 Fahrenheit. Superconductors are used to make very powerful magnets such as in medical magnetic resonance imaging, or MRI, machines. They usually need to be cooled to almost absolute zero, which is minus 450 degrees Fahrenheit, to work. Last year, Japanese scientists found that magnesium diboride, a cheap, readily available material, is a superconductor at minus 389 Fahrenheit, setting off a flurry of research. Like magnesium diboride, lithium borocarbide is made up of layers of different atoms. Normally, it's a good insulator, but the researchers predict that with the right treatment, it should be a superconductor at up to 100 Kelvin, which is minus 280 F. The researchers propose using "field-effect doping" to modify the material. Engineers routinely use chemicals to "dope" silicon to make semiconductors.

SENSOR WILL SAVE ENERGY, CUT POLLUTION

A University of Toronto professor has developed an industrial furnace sensor that he says will save energy, reduce pollution and save millions of dollars in electricity costs a year. "The optical laser sensor, which will be used for industrial purposes, will save 20 million kilowatt-hours a year or about a $1 million worth of electricity, says Murray Thomson, who works in the department of mechanical and industrial engineering. "Because the sensor improves the energy efficiency of the furnace, it will also reduce greenhouse gas emissions." The sensor measures thermal and chemical energy losses, information that is entered into a process control system. The system then readjusts parameters -- such as the amount of fuel and oxygen entering the industrial furnace -- to lower energy consumption. Since the sensor depends on a laser, it is reliable in the harsh furnace environment and has a quick response time when measuring excess energy.

ERRANT STEM CELLS LINKED TO SCHIZOPHRENIA

Neural stem cells are a ready supply of new parts for the constant wiring and rewiring of the brain's circuitry so the brain can learn new skills, interpret new data and rethink old ideas. But if those cells can't migrate to the right place and morph into the right kinds of neural links, cognitive and psychological functions fail. Researchers at the University of Illinois at Chicago have found that a protein called reelin, whose function in the adult brain has long been a mystery, is responsible for directing the migration of neural stem cells. The study, published in the March 19 issue of the Proceedings of the National Academy of Sciences, says neural stem cells are the precursors to the variety of cell types found in the brain. The study suggests one possible molecular mechanism underlies schizophrenia, a devastating psychiatric illness. "Perhaps in schizophrenics who lack reelin, the brain's stem cells can't find their way to make the appropriate neural connections," says Kiminobu Sugaya, the study's principal investigator. "As a result, perception and thinking may break down."

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