An X-ray outburst from the center of our galaxy is providing compelling new evidence that a monster black hole lurks at the Milky Way's core. (p. 148)

Preliminary results suggest that catnip may be more effective at repelling mosquitoes than the widely used chemical DEET. (p. 148)

HIV may directly interact with cells in arteries, predisposing people to heart attacks. (p. 149)

A right whale may weigh some 70 tons, but unlike other marine mammals studied so far, it tends to float rather than sink at great depths. (p. 149)

Three new studies indicate that altered transmission of glutamate, a key brain chemical, plays an influential role in the severe mental disorder known as schizophrenia. (p. 150)

Ocean-floor sediments drilled from Antarctic regions recently covered by ice shelves suggest that those shelves were much younger than scientists had previously thought. (p. 150)

Marine ecologists report the development of a new remote-sensing system that can assess the health of coral reefs from planes. (p. 151)

A strain of influenza virus that struck in Hong Kong in 1997 got some of its lethality from a mutation in the gene encoding an enzyme called PB2. (p. 151)

Proteins called toll-like receptors allow human immune cells to detect microbes. (p. 152)

Chemists have found that a new class of compounds, called ionic liquids, can substitute for widely used, messy organic solvents while also performing better and producing new products of interest to industry. (p. 156)

A short training course in matching sound sequences with visual patterns shows promise as a way to boost reading skills in children with dyslexia. (p. 155)

Researchers have identified several brain areas that together underlie the experience of feeling certain that a piece of forgotten information is nonetheless on the tip of one's tongue. (p. 155)

A new study of the genetics of African elephants shows that forest dwellers differ so much from those roaming the savannas that the two may be separate species. (p. 155)

Auklet feathers carry a cocktail of citrus-smelling chemicals, including compounds that squashbugs secrete to repel predators. (p. 155)

A low-fat diet and regular exercise can ward off diabetes in people at high risk of developing the disease. (p. 159)

Patients with the most severe emphysema shouldn't undergo major surgery that removes part of their damaged lungs. (p. 159)

Researchers have developed microscopic spheres that can sneak insulin past the stomach so it can be absorbed in the small intestine. (p. 159)

A new technique replaces the air in food packages with argon instead of widely used nitrogen, improving taste and shelf life. (p. 159)

A new material that dentists might eventually put under fillings and braces secretes calcium and phosphate ions to rebuild teeth as cavities form. (p. 159)