| This thesis addresses several problems at the interface between physics and biology, ranging across systems and scales from macroscopic to cellular levels, where quantitative methodologies can shed light on the organizing principles underlying the functioning of biological systems. At the macroscopic scale, the thesis investigates diffusive transport and nonlinear wave propagation in cardiac tissues. At the cellular scale, it examines spatial localization of transporters in the developing sea-urchin embryo. As the dominant transport mechanism in many biological systems, the physics of diffusion constitutes a unifying theme in understanding the functioning of these various biological processes. The methodology employed consists of mathematical modeling and analysis and high performance scientific computing.;The thesis consists of three parts: (Part I) explores electrical wave propagation in a minimally realistic fiber architecture model of the left ventricle. (Part II) explores transport through the myocardium of pharmocokinetic agents placed in the pericardial sac, in collabration with Prof. Keith March's group at IU Medical School. (Part III) explores the role of diffusion in the localization of P-gp transporters in early stages of sea-urchin embryonic development, in collaboration with the experimental group of Prof. David Epel (Stanford University, Department of Biology). |
