Fueled only by promising studies of cells, a California research team has invited controversy by beginning to give a little-used malaria drug to patients who have the human version of mad cow disease. (p. 100)

Studying a star in the Big Dipper, astronomers have for the first time found a planetary system that reminds them of home. (p. 100)

The first report on Atlantic bluefin tuna wearing electronic tags reveals much more dashing across the ocean than expected. (p. 101)

When a set of instruments monitoring an underwater volcano got trapped in an eruption in early 1998, the scientists who had deployed the sensors ended up with more data than they bargained for. (p. 102)

Two compounds stop menstruation in monkeys, suggesting that similar drugs might someday enable women to bypass monthly bleeding. (p. 102)

Researchers have designed simple new films for indicating the presence of worrisome airborne chemicals. (p. 103)

To make denser accelerator beams that may open new doors in physics, researchers have chilled ions in a miniature test accelerator until the ions coalesced into crystals. (p. 103)

Astronomers have found what could be the first evidence of water-bearing objects that orbit a star other than the sun. (p. 105)

Close-up views of the asteroid 433 Eros, showing jagged rocks, fields of boulders, and debris-filled craters, are featured in a minute-long movie. (p. 105)

President Bush said he would support work on stem cells that already had been propagated from embryos otherwise fated for disposal in fertility clinics, but he opposes financing the destruction of additional embryos to create new cell lines. (p. 105)

A panel reviewing human cloning heard the pros and cons of the issue during a fiery debate. (p. 105)

Paleontologists engaged in a contentious debate about the origins of feathers often reach interpretations that are poles apart, and they defend their views with fervor. (p. 106)

A genetically engineered drug that fuses an antibody to a toxin attacks cancerous cells in hairy-cell leukemia. (p. 109)

The inflammatory enzyme Cox-2 is present in stomach tumors, suggesting that drugs that inhibit the enzyme might help supress tumor formation. (p. 109)

Expectant mothers who've already given birth by cesarean section put themselves at increased risk of uterine rupture by trying vaginal birth. (p. 109)

The protein Ki-67, sometimes present on tissue lining the lungs, may act as a warning sign of lung cancer risk for ex-smokers. (p. 109)

Widely publicized concerns about vaccination leading to autism, multiple sclerosis, and diabetes have not been borne out by research. (p. 110)