A Princeton chemist has developed a general mathematical system for designing materials that perform two functions at once, even when the desired properties sometimes conflict with each other. Salvatore Torquato and colleagues used computers to calculate the optimum structure for any material that is a composite of two substances with differing properties. The achievement is the first simple example of a mathematically rigorous method for optimizing the design of multifunctional composites, which are an increasingly common kind of material.
Scientists have taken an important step toward understanding a virus that infects and lies dormant in most people, but emerges as a serious illness in transplant patients, some newborns and other people with weakened immune systems. The virus, called human cytomegalovirus, enters the bone marrow and can hide there for a lifetime. Until now, however, scientists had not been able to study the virus in its latent stage because it infects only humans and does not readily infect or become dormant in laboratory strains of bone marrow cells. In a new study researchers demonstrated a laboratory system for studying the virus in its latent stage and discovered a set of genes that may give the virus its great capacity for stealth.