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The Discontinuous Galerkin Time Domain (DGTD) methods are now popular for the solution of wave propagation problems required for the accurate transient modeling of systems involving electromagnetic waves in many emerging technologies. While Yees explicit, energy-conserving FDTD method is still prominent but restructed to structured grids and second-order accuracy, DGTD methods 1) are able to deal with unstructured, possibly locally-refined meshes around complex geometries, 2) remain fully explicit with easy parallelization, and 3) have extensions to high orders of accuracy. Non-dissipative versions exist, where some discrete electromagnetic energy is exactly conserved. However, the stability limit of the methods, related to the smallest elements in the mesh, calls for the construction of local-time stepping algorithms. These schemes have already been developed for N-body mechanical problems and are known as symplectic schemes. In this paper, they are transformed and applied to DGTD methods on wave propagation problems in order to obtain stable and accurate local time-stepping algorithms.

We present in this paper a time-domain Discontinuous Galerkin dissipation-free method for the transient solution of the three-dimensional linearized Euler equations around a steady-state solution. In the general context of a non-uniform supporting flow, we prove, using the well-known symmetrization of Euler equations, that some aeroacoustic energy satisfies a balance equation with source term at the continuous level, and that our numerical framework satisfies an equivalent balance equation at the discrete level and is genuinely dissipation-free. Moreover, there exists a correction term in aeroacoustic variables such that the aeroacoustic energy is exactly preserved, and therefore the stability of the scheme can be proved. This leads to a new filtering of Kelvin-Helmholtz instabilities. In the case of P1 Lagrange basis functions and tetrahedral unstructured meshes, a parallel implementation of the method has been developed, based on message passing and mesh partitioning. Three-dimensional numerical results confirm the theoretical properties of the method. They include test-cases where Kelvin-Helmholtz instabilities appear and can be eliminated by addition of the source term.

Shallow-Water Equations are encountered in many applications related to hydraulics, flood propagation or dam break problems. This set of nonlinear hyperbolic equations models a fluid flow in a domain where the depth of the fluid is much lower than its horizontal dimensions. Usually, these equations are treated using Finite Difference, Finite Volume or Continuous Finite Element methods. In this paper, we develop a Runge-Kutta Discontinuous Galerkin Finite Element Method to deal with the one-dimensional Shallow-Water Equations. Discontinuous Galerkin Methods are currently experiencing a vigorous development. Advantages of such methods include their high order of accuracy and their ease to handle complicated geometries. For Shallow-Water Equations, the goals of this work are on the one hand to preserve quiescent flows (and, more generally, steady-states) in the presence of bathymetric terms and, on the other hand, to handle accurately flooding and drying. Drawing on earlier ideas for Finite Volume Methods [1], we design a Discontinuous Galerkin Method that preserves flows at rest. We assess the scheme on various one-dimensional problems including subcritical and trancritical flows as well as cases with flooding and drying [2]. These tests confirm the stability of the scheme and its high accuracy. Moreover we present a generalization of the method to the two-dimensional case that we illustrate with some numerical results.

The purpose of this phase 1/2 study was to evaluate toxicity, tumor evolution and immunologic response following administration of a fixed dose of a recombinant MAGE-3 protein by subcutaneous and intradermal routes in the absence of immunologic adjuvant. Thirty-two patients with detectable metastatic melanoma expressing gene MAGE-3 were included and 30 received at least one injection with a fixed dose of a ProtD-MAGE-3 fusion protein. The immunization schedule included 6 intradermal and subcutaneous injections at 3-week intervals. Afterward, patients without major tumor progression who required other treatments received additional vaccinations at increasing time intervals. The vaccine was generally well tolerated. Among the 26 patients who received at least 4 vaccinations, we observed 1 partial response and 4 mixed responses. For these 5 responding patients, time to progression varied from 3.5 to 51+ months. An anti-MAGE-3 CD4 T-lymphocyte response was detected in 1 out of the 5 responding patients. The majority of patients had no anti-MAGE-3 antibody response. The clinical and immunologic responses generated by the vaccine are rather limited. Nevertheless, given the potential antitumor efficacy and the very mild toxicity of vaccinations, further studies combining MAGE proteins and/or peptides with potent immunologic adjuvants are warranted, not only in metastatic melanoma, but also in the adjuvant setting. (c) 2005 Wiley-Liss, Inc.

[Clinico-experimental studies on the use of hyaluronic acid in skin healing processes. Preliminary data]