Earth, Energy & Environment

Researchers ID new mammal down under

In the current crisis of global biodiversity loss, the discovery of new species is a welcome addition. But the recent finding that the mountain brushtail possum, an arboreal marsupial mammal of Australian wet forests, is actually made up of two species also poses new conservation challenges. The new species is proposed in an article in the latest Australian Journal of Zoology (Volume 50, Issue 4), authored by Earthwatch-supported biologist Dr. David Lindenmayer (Australian National University) and colleagues. “Geographic dimorphism in the Mountain Brushtail Possum (Trichosurus caninus) – the case for a new species,” describes how the northern and southern populations of the mountain brushtail possum are both morphologically and genetically distinct.

Rupture of Denali fault responsible for 7.9-mag Alaskan earthquake

Geologists just back from a reconnaissance of the 7.9-magnitude Alaska earthquake of November 3 confirm that rupture of the Denali fault was the principal cause of the quake. According to Caltech geology professor Kerry Sieh, Central Washington University geological sciences professor Charles Rubin, and Peter Haeussler of the U.S. Geological Survey, investigations over a week-long period revealed three large ruptures with a total length of about 320 kilometers. The principal rupture was a 210-kilometer-long section of the Denali fault, with horizontal shifts of up to nearly 9 meters (26 feet). This places the rupture in the same class as those that produced the San Andreas fault’s two historical great earthquakes in 1906 and 1857. These three ruptures are the largest such events in the Western Hemisphere in at least the past 150 years.

Accidental finding could lead to full-spectrum solar cell

Researchers have found that the electrical properties of the semiconductor indium nitride are different from what been previously thought — by a wide margin. The result is that an alloy incorporating the material can convert virtually the full spectrum of sunlight — from the near infrared to the far ultraviolet — to electrical current. “It’s as if nature designed this material on purpose to match the solar spectrum,” said one researcher involved.

Transplanted muscle cells can take root in damaged hearts

The first direct evidence that muscle cells transplanted from within a heart patient’s body could help heal their damaged heart muscle is being reported today. In the study, a small sample of cells from patients’ thigh muscles were taken, and “satellite” myoblast cells were isolated and grown in culture until they multiplied. These cells were then injected into the hearts of four patients who were receiving heart-assisting implants to help them survive until they could get a heart transplant. The results showed that the injected cells not only survived in their new environment, but began to form muscle fibers.

Key to global warming prediction within reach

The search for a Holy Grail of climate science may be nearing an end, if an MIT-led project is launched by NASA to measure soil moisture?data needed to predict global change, assess global warming and support the Kyoto Protocol. That measurement has been missing from the array of clues?rainfall, atmospheric chemistry, humidity and temperature?used by scientists to predict change in the local and global climate. Using soil moisture, they can calculate evaporation?the process that links the water, energy and carbon cycles?giving them a better understanding of global change.

Gene Researchers Close In On Nicotine’s ‘Evil Cousin’

Nicotine isn’t all bad, despite its addictive qualities and its presence in tobacco products, increasingly taboo in these health-conscious times. As a chemical compound, nicotine even has beneficial properties. It’s used around the world as a relatively cheap, environmentally friendly insecticide, repelling bugs that attack tobacco and other plants, and – contrary to popular misconceptions – it is not a carcinogen. Take a nicotine molecule and snip off a methyl group, though, and you’ve got nicotine’s evil cousin: nornicotine.

Mitochondrial DNA as a Cancer Biomarker

As part of a national effort to identify biomarkers for early detection of cancer, the federal National Institute for Standards and Technology is developing safer, faster, and more efficient methods for sequencing the DNA from mitochondria, the tiny energy factories of cells. Mutations within the DNA of mitochondria — a circular strand containing more than 16,000 nucleotide base pairs — have been implicated in a variety of cancers. In one small study by Johns Hopkins University, for example, such mutations were found in lung cancer cells but not the normal cells of the same patients. NIST researchers are working to validate the mitochondrial DNA sequence measurement technology and increase the speed of the sequencing protocol. They hope that this will lead to improved methods that could be used in clinical applications.

Using Computers, Scientists Successfully Predict Evolution of E. Coli

For more than a decade, researchers have been trying to create accurate computer models of Escherichia coli (E. coli), a bacterium that makes headlines for its varied roles in food poisoning, drug manufacture and biological research. By combining laboratory data with recently completed genetic databases, researchers can craft digital colonies of organisms that mimic, and even predict, some behaviors of living cells to an accuracy of about 75 percent. Now, NSF-supported researchers at the University of California at San Diego have created a computer model that accurately predicts how E. coli metabolic systems adapt and evolve when the bacteria are placed under environmental constraints.

Climate Change Linked to Population Shifts Among Mammals

Scientists have shown, for the first time, that changes in a large-scale climate system can synchronize population fluctuations in multiple mammal species across a continent-scale region. The study, to be published in the 14 November 2002 issue of the journal Nature, compares long-term data on the climate system known as the North Atlantic Oscillation with long-term data from Greenland on the population dynamics of caribou and muskoxen, which are large mammals adapted to breeding in the Arctic.