9406090 Belmonte This award is under the International Junior Investigator and Postdoctoral Fellows Program, which enables U.S. scientists and engineers to conduct three to twelve months of research abroad at research centers of proven excellence. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twelve-month postdoctoral research visit by Dr. Andrew L. Belmonte to work with Dr. Jorge R. Tredicce at the Institut NonLineaire de Nice. Dr. Belmonte proposes to study the motion of spiral wave defects, developing methods to attract and hold them by suppression of chemical reactivity in controlled regions, and measuring the strength of this "pinning." He also proposes to explore the creation and disruption of these defects, and their perturbation by complex boundary conditions and anisotropic or inhomogeneous media. The unpinning or disruption of such spiral defects would have important implications for the dynamics of ventricular fibrillation in the heart (leading to sudden death), which is thought to be caused by pinned spiral waves of electrical excitation in the muscle. ***
