We begin the week with interviews with two different best-selling authors. One of them, Robin Cook ("Coma") talks about his newest novel, "Cure," which revolves around the exciting field of regenerative medicine involving stem cells and how greed could undermine much needed research. The other is Mary Roach ("Stiff") whose latest book, "Packing for Mars," examines some of the incredible and often surprising challenges that are involved in putting human beings in space when it comes to matters like eating, sleeping, bathing, and going to the bathroom.