Dynamic Front Transitions and Spiral-Vortex Nucleation
  This is a study of front dynamics in reaction diffusion systems near Nonequilibrium Ising-Bloch bifurcations. We find that the relation between front velocity and perturbative factors, such as external fields and curvature, is typically multivalued. This unusual form allows small perturbations to induce dynamic transitions between counter-propagating fronts and nucleate spiral vortices. We use these findings to propose explanations for a few numerical and experimental observations including spiral breakup driven by advective fields, and spot splitting. 
Christian Elphick (Department of Physics, Universidad T\'ecnica   Federico Santa Maria, Valparaiso, Casilla 110-V, Chile), A...