Optimised design of architectures in finite precision for signal processing dedicated systems

The new submicronic technologies offer real capacities in terms of integration of signal processing dedicated systems, images and digital communications. To control these new technologies, new design methods and new computer-aided design tools have appeared : the system design and the behavioral design. These methods offer an effective link between algorithm designers and circuit designers. But it creates also new methodological problems for design automation. Our study is in keeping with this process and is more particularly focused on transformation under constraints, from the abstract types (used in the declaration of variables for the behavioral specification) to the vector of bit types (used in the logical design). We illustrate our methodology by the use of the behavioral synthesis tool Gaut, developed in the Lester laboratory. We present the different models, analysis and methods used in a way to control computing noises in finite precision and real time architectures. Implementation of signal processing and image applications gives the efficiency and the importance of this approach in terms of architecture optimization.Les nouvelles technologies sub-microniques offrent de grandes capacités en terme d'intégration de systèmes qui peuvent satisfaire les applications de traitement du signal, des images et de communications numériques (TDSI) les plus exigeantes. Pour maîtriser ces nouvelles technologies, de nouvelles méthodes de conceptions et outils de CAO voient le jour: conception système et conception comportementale. Si ces méthodes offrent une passerelle efficace entre les concepteurs en algorithmes et les concepteurs en circuits, elles posent cependant de nouveaux problèmes méthodologiques pour l'automatisation de la conception. Notre travail entre dans cette démarche et se focalise en particulier sur la transformation, sous contraintes, des types abstraits utilisés pour les déclarations de variables au niveau de spécification comportementale vers les types « vecteur de bit » que savent intégrer les outils de conception logique. Nous nous plaçons dans le cadre de l'outil de synthèse comportementale GAUT, développé au LESTER pour lequel nous présentons les différents modèles, analyses et méthodes d'optimisation définies et mises en oeuvre pour la maîtrise des bruits de calculs dans les architectures temps réel en précision finie. Les implémentations d'applications de TDSI que nous avons réalisées, montrent l'efficacité et l'importance de cette démarche en terme d'optimisation des architectures

Méthode d'implantation d'algorithmes de traitement du signal en précision finie

Les contraintes imposées aux applications temps réel des systèmes d'électronique embarquée sont d'une part la réduction de surface et d'autre part la réduction de consommation. La conception d'architectures utilisant des opérateurs en précision finie permet d'optimiser ces contraintes. En effet, nous pouvons obtenir, à l'aide de la méthode présentée, intégrée à un outil de synthèse architecturale, des ASICs possédant un ou plusieurs chemins de traitement de données à des formats différents, optimisés pour une contrainte de rapport signal à bruit de calcul. Cet article présente une méthode d'aide au dimensionnement des chemins de données ce qui nécessite une étude des problèmes de débordement et une analyse de la puissance de bruit de calcul. Cette méthode d'adéquation algorithme architecture sera illustrée par une application de traitement non récursif (FFT), puis par une application de traitement récursif (Filtre à Réponse Impulsionnelle Infinie). Associée à un outil de synthèse haut niveau, cette méthode nous permet de répondre au mieux aux contraintes de la conception

Biodiversity, Species Protection, and Animal Welfare Under International Law

The chapter explores the influence of the concept of animal welfare on international biodiversity law. A close examination of the recent evolution of this branch of international law shows that animal welfare has an ambivalent place in biodiversity-related agreements. Indeed, while welfare is only a faint consideration in the development of international regimes dealing with biodiversity as a whole, the concept has become an essential element for agreements dealing with the conservation of specific endangered species. Despite its role in these agreements, the place of animal welfare in international biodiversity law highlights that this corpus of rules is currently insufficient to be an effective tool for the protection of wildlife welfare. The last section of this study suggests that the adoption of international rules aiming at ensuring the protection of wild animals’ welfare could serve the double purpose of strengthening the conservation purpose of biodiversity regimes while also filling the welfare gap of international biodiversity law

The four and a half LIM-only protein 2 regulates liver homeostasis and contributes to carcinogenesis

BACKGROUND & AIMS: The four and a half LIM-only protein 2 (FHL2) is upregulated in diverse pathological conditions. Here, we analyzed the effects of FHL2 overexpression in the liver of FHL2 transgenic mice (Apo-FHL2). METHODS: We first examined cell proliferation and apoptosis in Apo-FHL2 livers and performed partial hepatectomy to investigate high FHL2 expression in liver regeneration. Expression of FHL2 was then analyzed by real time PCR in human hepatocellular carcinoma and adjacent non-tumorous livers. Finally, the role of FHL2 in hepatocarcinogenesis was assessed using Apo-FHL2;Apc(lox/lox) mice. RESULTS: Six-fold increase in cell proliferation in transgenic livers was associated with concomitant apoptosis, resulting in normal liver mass. In Apo-FHL2 livers, both cyclin D1 and p53 were markedly increased. Evidence supporting a p53-dependent cell death mechanism was provided by the findings that FHL2 bound to and activated the p53 promoter, and that a dominant negative p53 mutant compromised FHL2-induced apoptosis in hepatic cells. Following partial hepatectomy in Apo-FHL2 mice, hepatocytes displayed advanced G1 phase entry and DNA synthesis leading to accelerated liver weight restoration. Interestingly, FHL2 upregulation in human liver specimens showed significant association with increasing inflammation score and cirrhosis. Finally, while Apo-FHL2 mice developed no tumors, the FHL2 transgene enhanced hepatocarcinogenesis induced by liver-specific deletion of the adenomatous polyposis coli gene and aberrant Wnt/β-catenin signaling in Apc(lox/lox) animals. CONCLUSIONS: Our results implicate FHL2 in the regulation of signaling pathways that couple proliferation and cell death machineries, and underscore the important role of FHL2 in liver homeostasis and carcinogenesis

LIM-only protein FHL2 activates NF-κB signaling in the control of liver regeneration and hepatocarcinogenesis

Four-and-a-half LIM-only protein 2 (FHL2) is an important mediator in many signaling pathways. In this study, we analyzed the functions of FHL2 in nuclear factor κB (NF-κB) signaling in the liver. We show that FHL2 enhanced tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) activity in transcriptional activation of NF-κB targets by stabilizing the protein. TRAF6 is a binding partner of FHL2 and an important component of the Toll-like receptor-NF-κB pathway. Knockdown of FHL2 in 293-hTLR4/MD2-CD14 cells impaired lipopolysaccharide (LPS)-induced NF-κB activity, which regulates expression of inflammatory cytokines. Indeed, FHL2(-/-) macrophages showed significantly reduced production of TNF and interleukin 6 (IL-6) following LPS stimulation. TNF and IL-6 are the key cytokines that prime liver regeneration after hepatic injury. Following partial hepatectomy, FHL2(-/-) mice exhibited diminished induction of TNF and IL-6 and delayed hepatocyte regeneration. In the liver, NF-κB signaling orchestrates inflammatory cross talk between hepatocytes and hepatic immune cells that promote chemical hepatocarcinogenesis. We found that deficiency of FHL2 reduced susceptibility to diethylnitrosamine-induced hepatocarcinogenesis, correlating with the activator function of FHL2 in NF-κB signaling. Our findings demonstrate FHL2 as a positive regulator of NF-κB activity in liver regeneration and carcinogenesis and highlight the importance of FHL2 in both hepatocytes and hepatic immune cell