We consider the Cauchy problem for $n\times n$ strictly hyperbolic systems of nonresonant balance laws $$ \left\{\begin{array}{c} u_t+f(u)_x=g(x,u), \qquad x \in \reali, t>0\\ u(0,.)=u_o \in \L1 \cap \BV(\reali; \reali^n), \\ | \la_i(u)| \geq c > 0 \mbox{ for all } i\in \{1,\ldots,n\}, \\ |g(.,u)|+\norma{\nabla_u g(.,u)}\leq \om \in \L1\cap\L\infty(\reali), \\ \end{array}\right. $$ each characteristic field being genuinely nonlinear or linearly degenerate.

We introduce and discuss a three-dimensional mesoscopic lattice Boltzmann model for the numerical simulation of strongly-interacting fluids with dynamic inhomogeneities. The model is based on an extension of the standard lattice Boltzmann dynamics in which streaming between neighboring lattice sites is constrained by the value of the nonlocal density of the surrounding fluid. The resulting dynamics exhibits typical features of dynamically heterogeneous fluids, such as long-time relaxation, non-Gaussian density distributions and dynamic heterogeneities.

We have developed a rat brain organotypic culture model, in which tissue slices contain cortex-subventricular zone-striatum regions, to model neuroblast activity in response to in vitro ischemia. Neuroblast activation has been described in terms of two main parameters, proliferation and migration from the subventricular zone into the injured cortex. We observed distinct phases of neuroblast activation as is known to occur after in vivo ischemia.

We present a numerical study of anisotropic statistical fluctuations in homogeneous turbulent flows. We give an argument to predict the dimensional scaling exponents, (p+j)/3, for the projections of p-th order structure function in the j-th sector of the rotational group. We show that measured exponents are anomalous, showing a clear deviation from the dimensional prediction. Dimensional scaling is subleading and it is recovered only after a random reshuffling of all velocity phases, in the stationary ensemble.

We study the on-line version of the well known problem of scheduling a set of $n$ independent multiprocessor tasks with prespecified processor allocations on a set of identical processors in order to minimize the makespan. Recently, it has been proven that even in the off-line case with unit processing time tasks no polynomial time approximation algorithm can be found with approximation factor $m^{{1}/{2}-\eps}$ for any $\eps >0$, unless \NP=\ZPP. We first study simple approximation and on-line algorithms based on the classical first-fit technique.

We present a multiscale approach to the modeling of polymer dynamics in the presence of a fluid solvent. The approach combines Langevin molecular dynamics ( MD) techniques with a mesoscopic lattice Boltzmann (LB) method for the solvent dynamics. A unique feature of the present approach is that hydrodynamic interactions between the solute macromolecule and the aqueous solvent are handled explicitly, and yet in a computationally tractable way due to the dual particle-field nature of the LB solver.

PELCR is an environment for lambda-terms reduction on parallel/distributed computing systems. The computation performed in this environment is a distributed graph rewriting and a major optimization to achieve efficient execution consists of a message aggregation technique exhibiting the potential for strong reduction of the communication overhead. In this paper we discuss the interaction between the effectiveness of aggregation and the schedule sequence of rewriting operations. Then we present a Priority Based (BP) scheduling algorithm well suited for the speci c aggregation technique.

The need for anti-HIV-1 vaccines is universally recognized. Although several potential vaccine formulations are being tested in clinical trials, the complexity of the viral system and the length of the experimentation required and its costs makes the goal of obtaining such a vaccine still elusive. We have built a mathematical model for the simulation of HIV-1 infection spreading into the body, which allows us study in silico the effect of hypothetical anti-HIV-1 vaccines having different properties.

We present a mesoscopic lattice model for non-ideal fluid flows with directional interactions, mimicking the effects of hydrogen bonds in water. The model supports a rich and complex structural dynamics of the orientational order parameter, and exhibits the formation of disordered domains whose size and shape depend on the relative strength of directional order and thermal diffusivity.