Les espaces de l'halieutique

L'étang de Thau est un espace lagunaire semi fermé dont les communications avec la mer sont limitées. L'exploitation de la palourde, ressource intrinsèquement peu mobile, est au coeur de l'activité de pêche dans cet étang. Il semble donc, a priori, que les notions d'espace mis en oeuvre par l'exploitation de cette ressource présentent un caractère de proximité et une dimension localisée à l'écosystème "étang de Thau". Dès lors, on pourrait penser que la connaissance écologique de ce milieu - où d'importants programmes scientifiques ont été réalisées -, alliée à la faible mobilité de cette population de bivalves fouisseurs, constituent des conditions favorables à une gestion "efficace" de cet écosystème. Ce sentiment est renforcé par le contexte social dans lequel évoluent les communautés de pêcheurs qui ont derrière elles une longue pratique de la gestion (prud'homies). Or, après une période florissante achevée en 1992, cette pêcherie traverse une crise aiguë. Les professionnels constatent en effect une forte diminution des stocks qui se traduit par (i) une régression des quantités pêchées par jours de travail (PUE) (ii) une diminution des prix (contre toute logique de marché) et (iii) une décroissance du nombre de pêcheurs. Parallèlement on observe une transformation des méthodes de pêche avec la généralisation de la pêche en plongée aux dépens de "l'arselière" technique traditionnelle qui a quasiment disparu. Dans ce contexte, et à la demande de la profesison, un programme pluridisciplinaire (programme Palourde) a été mis en oeuvre afin d'identifier les limites du système actuel puis d'élaborer un nouveau système de gestion. Ce travail a été mené selon une démarche de concertation élargie de l'ensemble des partenaires de l'exploitation (pêcheurs, mareyeurs, gestionnaires) et de façon négociée entre les acteurs... (Résumé d'auteur

La Inquisició a debat

Los profesores J. Contreras, J.-P. Dedieu, H. Kamen, F. Tomás y Valiente y R. García cárcel debaten el tema inquisitorial a partir de cuatro cuestiones fundamentales: ¿fue la Inquisición el resultado de una superestructura impuesta artificialmente a la sociedad o, por el contrario, emanó de la propia sociedad?, ¿represión inquisitorial teórica o efectiva?, ¿fue excepcional la Inquisición española en el marco europeo?, ¿cuál es la naturaleza de la Inquisición, religiosa o política?.In this transcription, Contreras, Dedieu, Kamen, Tomás y Valiente and García Cárcel debate the Inquisition focusing on four main questions: the Inquisition as a result of un artificially imposed to the society superstructure or, on the contrary, as an emanation of that society; the inquisitorial repression as merely theoretical or really effective; the supposed exceptionality, in an European context, of Spanish Inquisition and the real nature, religious or political, of the Inquisition

Ethanol application at veraison decreases acidity in Cabernet Sauvignon grapes

Research NoteSpraying ethanol (5 % v/v in water) onto grape clusters at mid-veraison led to a 30 % drop in the malic acid concentration at harvest. As a consequence, titratable acidity also dropped by 10 %. The concentration of tartaric acid did not change significantly. The mode of action of ethanol on malic acid metabolism is discussed.

Adjuvants and delivery systems in veterinary vaccinology: current state and future developments

Modern adjuvants should induce strong and balanced immune responses, and it is often desirable to induce specific types of immunity. As an example, efficient Th1-immunity-inducing adjuvants are highly in demand. Such adjuvants promote good cell-mediated immunity against subunit vaccines that have low immunogenicity themselves. The development of such adjuvants may take advantage of the increased knowledge of the molecular mechanisms and factors controlling these responses. However, knowledge of such molecular details of immune mechanisms is relatively scarce for species other than humans and laboratory rodents, and in addition, there are special considerations pertaining to the use of adjuvants in veterinary animals, such as production and companion animals. With a focus on veterinary animals, this review highlights a number of approaches being pursued, including cytokines, CpG oligonucleotides, microparticles and liposomes. (Résumé d'auteur

From error bounds to the complexity of first-order descent methods for convex functions

This paper shows that error bounds can be used as effective tools for deriving complexity results for first-order descent methods in convex minimization. In a first stage, this objective led us to revisit the interplay between error bounds and the Kurdyka-\L ojasiewicz (KL) inequality. One can show the equivalence between the two concepts for convex functions having a moderately flat profile near the set of minimizers (as those of functions with H\"olderian growth). A counterexample shows that the equivalence is no longer true for extremely flat functions. This fact reveals the relevance of an approach based on KL inequality. In a second stage, we show how KL inequalities can in turn be employed to compute new complexity bounds for a wealth of descent methods for convex problems. Our approach is completely original and makes use of a one-dimensional worst-case proximal sequence in the spirit of the famous majorant method of Kantorovich. Our result applies to a very simple abstract scheme that covers a wide class of descent methods. As a byproduct of our study, we also provide new results for the globalization of KL inequalities in the convex framework. Our main results inaugurate a simple methodology: derive an error bound, compute the desingularizing function whenever possible, identify essential constants in the descent method and finally compute the complexity using the one-dimensional worst case proximal sequence. Our method is illustrated through projection methods for feasibility problems, and through the famous iterative shrinkage thresholding algorithm (ISTA), for which we show that the complexity bound is of the form $O(q^{k})$ where the constituents of the bound only depend on error bound constants obtained for an arbitrary least squares objective with $\ell^1$ regularization

LRP-1 Promotes Cancer Cell Invasion by Supporting ERK and Inhibiting JNK Signaling Pathways

Background: The low-density lipoprotein receptor-related protein-1 (LRP-1) is an endocytic receptor mediating the clearance of various extracellular molecules involved in the dissemination of cancer cells. LRP-1 thus appeared as an attractive receptor for targeting the invasive behavior of malignant cells. However, recent results suggest that LRP-1 may facilitate the development and growth of cancer metastases in vivo, but the precise contribution of the receptor during cancer progression remains to be elucidated. The lack of mechanistic insights into the intracellular signaling networks downstream of LRP-1 has prevented the understanding of its contribution towards cancer. Methodology/Principal Findings: Through a short-hairpin RNA-mediated silencing approach, we identified LRP-1 as a main regulator of ERK and JNK signaling in a tumor cell context. Co-immunoprecipitation experiments revealed that LRP-1 constitutes an intracellular docking site for MAPK containing complexes. By using pharmacological agents, constitutively active and dominant-negative kinases, we demonstrated that LRP-1 maintains malignant cells in an adhesive state that is favorable for invasion by activating ERK and inhibiting JNK. We further demonstrated that the LRP-1-dependent regulation of MAPK signaling organizes the cytoskeletal architecture and mediates adhesive complex turnover in cancer cells. Moreover, we found that LRP-1 is tethered to the actin network and to focal adhesion sites and controls ERK and JNK targeting to talin-rich structures. Conclusions: We identified ERK and JNK as the main molecular relays by which LRP-1 regulates focal adhesion disassembly of malignant cells to support invasion

Agrometerological study of semi-arid areas : an experiment for analysing the potential of time series of FORMOSAT-2 images (Tensift-Marrakech plain)

Earth Observing Systems designed to provide both high spatial resolution (10m) and high capacity of time revisit (a few days) offer strong opportunities for the management of agricultural water resources. The FORMOSAT-2 satellite is the first and only satellite with the ability to provide daily high-resolution images over a particular area with constant viewing angles. As part of the SudMed project, one of the first time series of FORMOSAT-2 images has been acquired over the semi-arid Tensift-Marrakech plain. Along with these acquisitions, an experimental data set has been collected to monitor land-cover/land-use, soil characteristics, vegetation dynamics and surface fluxes. This paper presents a first analysis of the potential of these data for agrometerological study of semi-arid areas