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L’unité d’enseignement « Immunopathologie » qui propose les brèves présentées dans ce numéro est suivie par des étudiants de divers parcours du Master Biologie Santé de l’Université de Montpellier. Ce Master rassemble des étudiants issus du domaine des sciences et technologies et de celui de la santé. On y étudie les bases physiopathologiques des maladies immunologiques, les cibles thérapeutiques et les mécanismes d’échappement des microorganismes et des tumeurs. Les articles présentés ont été choisis par les étudiants selon leur domaine de prédilection.

This paper presents and discusses the results of tests of breakup phenomenon of liquid water into a hypersonic cross §ow from the surface of a 7 degree half-angle cone model at zero degree angle of incidence. The present work shows the dependence of the liquid phase characteristics on the cross-section area of the injection hole in a Mach 6 cross flow. The results are analyzed qualitatively by imaging, by Interferometric Laser Imaging for Droplet Sizing (ILIDS), and by InfraRed Light Extinction Spectroscopy (IR-LES). Conclusions are drawn concerning the droplet size distribution and the liquid §ow ¦eld characteristics.

Lagrangian methods were first introduced to solve purely convective problems approximately. These problems include the compressible Euler equations in fluid mechanics, the Vlasov equation in plasma physics. These methods have been extended to non-purely convective problems, to take into account diffusion effects. This has been first done by addition of a random walk to the movement of particles (inclusion of a brownian effect) (Chorin A. J.) and the idea was to include most of the effects of the different operators to the dynamics of the particles. Other methods (Rehbach, C.-Fishelov D.) appeared with a different way ot thinking of particles as carriers of information, not only through their position as in the case of random walk, but also through their coefficient. Allowing not only the position but also the weight of the particles to evolve in time, has permitted particle methods to tackle more general operators. Indeed, particles are then no longer considered as clouds of independent points but rather as a set of interacting points. More recently a new method has emerged: the diffusion-velocity method ([Fronteau J.-Huberson S.). This method is based on the idea that the diffusion of a scalar quantity Omega has a prefered direction of transport, namely, that of Nabla Omega. This remark results in the transformation of a diffusion equation into an advection equation. In the first section, we present the diffusion-velocity method in the linear case and prove an existence and uniqueness result for a finite time. Additional results are then given for the 1-d case in the second section. In the third section, we consider the case of the 2-d, then 3-d, Navier-Stokes equations.

Since a report by the European Court of Auditor in December 2007, EU officials have been suggesting that the failure of the Common Fisheries Policy (CFP) results from too much non compliance and a weak and inefficient enforcement system. As a result, a stakeholder consultation was organised EU-wide, and a new control regulation has been presented by the European Commission in autumn 2008. The objective of the paper is to discuss the reality and the scope of this assertion in the situation of a French coastal fishery managed through effort control (the Saint-Brieuc scallop fishery). Key outlines of the French control strategy are presented for the first time, based on an extensive work with the key stakeholders (national and regional administrations and fishermen representatives). It shows that the system is rather complex, involving several administrations and various types of rules to be enforced. A preliminary assessment of the control strategy in place in Saint-Brieuc shows that despite rather high control costs, the level of non-compliance remains elevated. Such an unsatisfactory outcome, which can be explained by the low deterrence level observed, questions the efficacy of this kind of control strategies., Depuis un rapport de la Cour des comptes européenne en décembre 2007, les instances communautaires ont porté une attention particulière à l’une des causes possibles de l’échec de la politique commune de la pêche : trop de contrevenants à la réglementation et un système de contrôle globalement inefficace. L’article discute la nature et les fondements de cette explication dans le cas d’une pêcherie côtière française gérée par l’effort de pêche. Il présente pour la première fois le cadre général du contrôle des pêches en France et analyse sa mise en œuvre dans la pêcherie de Saint-Brieuc. Il montre que, malgré des coûts de contrôle importants, le niveau de fraude y reste relativement élevé. Ce bilan mitigé, qui peut s’expliquer par le faible niveau de dissuasion observé, conduit à s’interroger sur l’efficacité des différentes stratégies de contrôle dans cette pêcherie.

Nous presentons et analysons une methode particulaire deterministe pour un probleme modele d'advection-diffusion avec conditions aux limites de Dirichlet. Dans cette methode, les particules sont convectees par le champ de vitesse, les conditions aux limites et les effets de diffusion sont pris en compte par une modification des poids des particules. L'ordre de convergence de la methode est du meme type que dans le cas de l'espace tout entier