15Th Conference on Nonequilibrium Statistical Mechanics and Nonlinear Physics, Date: DEC 04-08, 2006, Location: Mar del Plata, ARGENTINA, Sponsors: Nat. Council of Scientific and Tech. Invest. (CONICET), Argentina;Nat. Agency of Sci. and Technol. Promotion (ANPCyT), Argentina;Latin American Center of Physics (CLAF);Air Force Office of Scientific Research (AFOSR), USA;Nat. Sci. Found. Office of Int. Science and Eng. (OISE), USA