21.   Her research focused on gynecological cancer and the epidemiology of cancer.

22.   Her later research focused on Native American settlements in the Boston area.

23.   His earliest research focused on plant nutrition, such as testing the relative efficiency of raising plants in soil, rather than afloat in nutrient-rich water.

24.   His research focused on modern information and signal-detection theories, which analyze the flow of sensory information.

25.   His research focused on the interaction of intense light with matter.

26.   His research focuses on the ribosome and how it works at the molecular level.

27.   His research has focused on how HIV, the AIDS virus, impairs the immune system and on ways to develop more effective therapies and a vaccine.

28.   His research focused on such matters as pulmonary and cardiac physiology, blood coagulation and the nature and treatment of clots that develop in blood vessels.

29.   Her own research focused on global competition in high-tech industries.

30.   His latest research focused on welding and soldering problems in metal processing.