Imagine being able to rapidly identify tiny biological molecules such as DNA and toxins using less than a drop of salt water in a system that can fit on a microchip.

In a paper appearing next week in the Proceedings of the National Academy of Sciences,* the team proves for the first time that a single nanometer-scale pore in a thin membrane can be used to accurately detect and sort different-sized polymer chains (a model for biomolecules) that pass through or block the channel.

Dr Pep Canadell, from the Global Carbon Project and CSIRO Marine and Atmospheric Research, says today in the journal Science that tropical deforestation releases 1.5 billion tonnes of carbon each year into the atmosphere.

"Deforestation in the tropics accounts for nearly 20 per cent of carbon emissions due to human activities," Dr Canadell says. "This will release an estimated 87 to 130 billion tonnes of carbon by 2100, which is greater than the amount of carbon that would be released by 13 years of global fossil fuel combustion. So maintaining forests as carbon sinks will make a significant contribution to stabilising atmospheric greenhouse gas concentrations."

Researchers at the University of Missouri-Columbia recently created a model of proline dehydrogenase, an important cancer-preventing enzyme in the human body, and analyzed how it works. A paper detailing their results was published today in the Journal of Biological Chemistry.

Parkinson's disease is well-known for its progression of motor disorders: stiffness, slowness, tremors, difficulties walking and talking. Less well known is that Parkinson's shares other symptoms with narcolepsy, a sleep disorder characterized by sudden and uncontrollable episodes of deep sleep, severe fatigue and general sleep disorder.

Investigators at St. Jude Children's Research Hospital have discovered inherited variations in certain genes that make children with acute lymphoblastic leukemia (ALL) susceptible to the toxic side effects caused by chemotherapy medications. The researchers showed that these variations, called polymorphisms, occur in specific genes known to influence pharmacodynamics (how drugs work in the body and how much drug is needed to have its intended effect).

A study released today provides some of the first solid evidence that warming-induced changes in ocean circulation at the end of the last Ice Age caused vast quantities of ancient carbon dioxide to belch from the deep sea into the atmosphere. Scientists believe the carbon dioxide (CO2) releases helped propel the world into further warming. The study, done by researchers at the University of Colorado, Kent State University and Columbia University's Lamont-Doherty Earth Observatory, appears in the May 10 advance online version of the leading journal Science.