Moderate amounts of regular walking improve brain function and attention in formerly sedentary seniors. (p. 115)

A long-term study of great skuas shows that when fishing fleets discard less fish, birds that scavenge for waste make up for the loss by increasing attacks on other seabirds. (p. 115)

A new theoretical model that describes a tsunami's interaction with winds may explain enigmatic observations associated with the waves and could lead to a technique for spotting them long before they hit shore. (p. 116)

Nanometer-scale polymer particles can extract pollutants from contaminated soil. (p. 116)

A new brain-imaging study in marmosets suggests that males sexually aroused by the scent of females may be thinking carefully before they mate, opposing the notion that nonhuman male mammals act purely upon a primal urge. (p. 117)

A genetic mutation more common in blacks than in whites increases the odds that people taking a common HIV medicine will suffer side effects that lead them to halt treatment. (p. 117)

A new study links antibiotic use to breast cancer, although it's not clear the drugs cause the disease. (p. 118)

A compact positron-emission tomography (PET) brain scanner may make possible studies of awake rats that link brain functions and behaviors. (p. 118)

A decade's worth of observations is spotlighting how the vast sea of gas surrounding a cluster of galaxies can alter the shape of a galaxy plowing through it. (p. 119)

Plants in which large numbers of simple units interact with one another appear to compute how to coordinate the actions of their cells effectively. (p. 123)

Although the Mars lander Beagle 2 is presumed dead, its mother craft, the European Space Agency's Mars Express, has transmitted its first data from a polar orbit about the Red Planet. (p. 125)

While pregnant, mice overproduce a kind of T cell that reins in other immune cells that might target the fetus. (p. 125)

A cloud of ultracold potassium atoms, manipulated by means of a magnetic field, has coalesced into a new super form of matter called a fermionic condensate. (p. 125)

Scientists have discovered the cascade of molecular events that underpins many cases of toxic shock syndrome. (p. 125)

Moving at nearly the speed of light, atomic nuclei hurtling through a huge particle collider may become mostly dense, flattened puddings of nuclear particles known as gluons. (p. 126)

A team of chemists has synthesized an unusual organic molecule that could lead to cheaper and lighter magnets. (p. 126)

Sifting through archival images, astronomers have identified the star whose explosive demise was recorded by telescopes last year. (p. 126)

(p. 127)