In this award, funded by the Experimental Physical Chemistry Program of the Division of Chemistry, Professor Oliver Steinbock of Florida State University (FSU), together with his student researchers, will investigate the dynamics of three-dimensional wave patterns in reacting chemical systems. These complex patterns arise solely from the interplay of local reactions and diffusion but do not involve fluid motion. The particular focus is on scroll waves which are rotating three-dimensional spirals. These structures exist in a variety of excitable systems, such as autocatalytic chemical reactions, aggregating slime mold colonies, neuronal tissue and the human heart. In the latter system, they possibly cause dangerous cardiac arrhythmias and fibrillation.
Many aspects of scroll wave dynamics can be explained in terms of the motion of the one-dimensional space curves (or "filaments") around which they rotate. This motion depends strongly on the local filament curvature and gradients in rotation phase. While today most of these factors are understood, little is known regarding the interaction of filaments with other filaments, high-frequency wave patterns, and unexcitable obstacles. The development of a comprehensive understanding of these types of interactions defines the primary intellectual merit of the proposed research. Experiments will employ the Belousov-Zhabotinsky reaction and use detection techniques such as optical tomography. Experimental results will be compared to numerical simulations of semi-quantitative and general kinematic models.
In particular, scroll wave pinning to and unpinning from unexcitable obstacles has a profound broader impact because dangerous reentrant waves in the human heart potentially attach to anatomical and pathological defects. In this context, the project will yield fundamental insights into the occurrence of "sudden cardiac death" which kills more than 300,000 people per year in the US alone. Moreover, our project will further the education of several undergraduate, graduate and postdoctoral students. Professor Steinbock will also continue his commitment to involve underrepresented groups and participate in programs that aim to increase their leadership roles in research and academia. In addition, his team will develop and implement novel outreach activities to communicate key results to the public FSU's Global Educational Outreach Program, PodCasts, popular websites such as YouTube, and local activities such as FSU's Honors Program and the "Saturday Morning Physics" series.
