News Scan Briefs; May 2003; Scientific American Magazine; by Charles Choi, Philip Yam, JR Minkel; 2 Page(s)

Pulling the Lever: Atomic-force microscopes have been the exquisitely delicate tools of choice for making three-dimensional images of atoms for almost two decades. One mathematician now concludes that its predominant design is fundamentally flawed. To form images, the microscopes rely on probes, as long as a human hair is wide, running over surfaces. In most instruments, the tip is mounted at the end of a V-shaped cantilever. Scientists believed that this chevron shape would resist the swaying that could lower image quality. John E. Sader of the University of Melbourne instead finds that the V shape enhances twisting and inadvertently degrades the performance of the instrument. "This came as a complete surprise, since intuition would dictate the opposite would be true," Sader says. He compares this result with a sheet of metal attacked by pliers: it is easier to bend the sheet at the corners than at the middle. Sader, whose calculations suggest that straight beams are better, reports his findings in the April Review of Scientific Instruments.-Charles Choi

Not So Happy Together: Married people are on average happier than singles, but that extra happiness looks negligible. A 15-year study of 24,000 subjects in Germany found that married folks get a boost in satisfaction shortly after the nuptials, but their levels of happiness drop back to their single days: on an 11-point scale, marrieds rated themselves only 0.1 point happier. People who were most satisfied with their lives react least positively to marriage and, in a surprise, most negatively to divorce or widowhood. The study, in the March Journal of Personality and Social Psychology, supports the notion that over time people's sense of well-being reverts to their general level of happiness, no matter what life events have occurred.-Philip Yam