In the United States, motor vehicle crashes are the leading cause of death for children over the age of one. Those facts are especially chilling to Michael Elliott, an assistant professor of biostatistics and a father of two, who studies the incidence of child injuries in automobile accidents.
Talk to anyone who works on AIDS, and they'll tell you it's not just an epidemic, it's a barometer. "It exposes the weak spots," says Rachel Snow, who's spent the last decade of her life working to combat the disease.
An estimated 15 percent of all couples have trouble conceiving, and although there are known risk factors that can account for the problem, "there's a lot that can't be accounted for," says John Meeker, an assistant professor of environmental health sciences.
The human immune system is a prodigious memory bank, and its ability to recall diseases can save our lives. But that same memory can also betray us.
When Valerie Myers went to South Africa in 1999 to conduct a research project, she faced an unsettling choice.