On Saturday, NewsHour Weekend examines a growing problem among many scientists who depend on grants from the government to carry out their work. As federal funding for biomedical research has been declining in real dollars over the past 13 years, getting a grant has become more difficult. Now, many say this hypercompetitive atmosphere may stunt not only the careers of promising scientists but also America's preeminent role in global science research. Special Correspondent Karla Murthy reports.