Since Dr. Weissman's initial discovery in 1988, a whole new area of scientific research has been devoted to stem cells. Stem cells have been found in several different tissues in the human body, including muscles and the brain. To advance the ability of scientists to be able to study human stem cells and tissues in living organisms, Dr. Weissman and his team also developed a procedure to transplant human tissues into mice with weakened immune systems. This new procedure gives scientists the opportunity to study many illnesses in more detail, and also to develop treatments for diseases such as leukemia.

Donald Kennedy

Donald Kennedy has served since June 2000 as editor-in-chief of Science. As editor-in-chief, he has written numerous editorials addressing issues at the interface of environmental science and policy. Topics have included climate change, biodiversity, and sustainability. Dr. Kennedy is president emeritus of Stanford University and a former commissioner of the U.S. Food and Drug Administration (FDA). A biologist by training, Dr. Kennedy’s research interests were originally in animal behavior and neurobiology. Kennedy's subsequent research has focused on exploring how the natural and social sciences can contribute to improving environmental practices and institutions.

Dr. Kennedy is Bing Professor of Environmental Science and a Senior Fellow in the Center for Environmental Science and Policy (CESP) at Stanford. Kennedy received his A.B. and Ph.D. degrees in biology from Harvard University. Dr. Kennedy maintains membership in the National Academy of Sciences, the American Academy of Arts and Sciences, and the American Philosophical Society.

Said Kennedy of his talk: This is an interesting time for science—not only because the science itself is exciting, but also because in a number of areas scientific advances have converged with important policy decisions and invited political controversy. I will cover of these, beginning with the advances in space science—which have renewed the controversy about whether limited NASA resources should be devoted to human exploration or to robotic missions to other parts of our solar system (Mars, Cassini) or deep space. The sequencing of the human genome has led to a new focus on what lies beyond the genes—mechanisms that control expression and thus are responsible for determining the developmental fates of cells. This is deeply embroiled with the controversy over stem cell research. A third area concerns the way in which the US is fulfilling its commitment to global HIV/AIDs prevention, and the debates over whether the emphasis on abstinence as opposed to making condoms more widely available is a workable strategy or merely a reflection of particular religious convictions. I plan to close with an evaluation of the new information about climate change, and an analysis of US policy responses as compared with those undertaken elsewhere, especially in the U.K.