Équation de production: adaptation du modèle de Ricker à un stock de poissons exploité par différents engins

The authors have developed the method used by Pianet and Le Hir (Doc.Sci.Cent. ORSTOM Pointe-Noire, 17, 1971) for the study of albacore (Thunnus albacares) in the Pointe-Noire region. The method is based on the fact that the ratio between unit of effort and number of fish for two fishing gears is equal to the ratio of their catchability coefficients

Statistics of the main purse seine fleets fishing in the Indian Ocean (1981-2008).

This document presents a summary of the statistics of French, Spanish, Italian, Seychelles and EU related NEI purse seine fleets fishing in the Indian Ocean since 1981: effort, catch by species and fishing type (log and free swimming schools), catch per unit of effort, sampling and mean weights for the main species. Since 2002, data from the European fleet (France and Spain) are collected within the framework of the EU “Data Collection Regulation” (DCR, Reg. 1543/2000 and 1639/2001), followed in 2008 by the “Community framework for the collection, management and use of data in the fisheries sector and support for scientific advice regarding the Common Fisheries Policy” (DCF, Reg 199/2008 and 665/2008). Data from other fleets are collected by SFA (Seychelles Fishing Authority). Data processing (species composition and size distribution) is done collectively for the whole fishery

Statistics of the main purse seine fleets fishing in the Indian Ocean (1981-2010).

This document presents a summary of the statistics of French, Spanish, Italian, Seychelles and EU related NEI purse seine fleets fishing in the Indian Ocean since 1981: effort, catch by species and fishing type (log and free swimming schools), catch per unit of effort, sampling and mean weights for the main species. Since 2002, data from the European fleet (France and Spain) are collected within the framework of the EU “Data Collection Regulation” (DCR, Reg. 1543/2000 and 1639/2001), followed in 2008 by the “Community framework for the collection, management and use of data in the fisheries sector and support for scientific advice regarding the Common Fisheries Policy” (DCF, Reg 199/2008 and 665/2008). Data from other fleets are collected by SFA (Seychelles Fishing Authority). Data processing (species composition and size distribution) is done collectively for the whole fishery

Bycatch species composition over time by tuna purse-seine fishery in the eastern tropical Atlantic Ocean.

Post-print

Integration of P2Y receptor-activated signal transduction pathways in G protein-dependent signalling networks

The role of nucleotides in intracellular energy provision and nucleic acid synthesis has been known for a long time. In the past decade, evidence has been presented that, in addition to these functions, nucleotides are also autocrine and paracrine messenger molecules that initiate and regulate a large number of biological processes. The actions of extracellular nucleotides are mediated by ionotropic P2X and metabotropic P2Y receptors, while hydrolysis by ecto-enzymes modulates the initial signal. An increasing number of studies have been performed to obtain information on the signal transduction pathways activated by nucleotide receptors. The development of specific and stable purinergic receptor agonists and antagonists with therapeutical potential largely contributed to the identification of receptors responsible for nucleotide-activated pathways. This article reviews the signal transduction pathways activated by P2Y receptors, the involved second messenger systems, GTPases and protein kinases, as well as recent findings concerning P2Y receptor signalling in C6 glioma cells. Besides vertical signal transduction, lateral cross-talks with pathways activated by other G protein-coupled receptors and growth factor receptors are discussed

NMR as a tool for kinetic studies: Application to the assessment of organotin reactivity

Halogen exchange rates are measured for various monoorganotins with NMR techniques, and an exchange mechanism is proposed. A correlation between kinetic data and the reactivity of the monoorganotins is then exemplified with radical allylic transfer and palladium catalyzed coupling reactions

Note upon difficulties, uncertainties and potential bias in the multispecies sampling and data processing of large tunas (yellowfin, bigeye and albacore) sampled in free schools by the Indian Ocean and Atlantic purse seiners.

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Effects of silicone coating degradation on GaN MQW LEDs performances using physical and chemical analyses

International audienceThis work presents a physics of failure (POF) methodology coupling failure signatures with physico-chemical analyses. The aim is to work out electro-optical failure signatures located in packaged InGaN/GaN Multiple Quantum Wells Light Emitting Diodes (MQW LEDs). Electrical and optical characteristics performed after accelerated ageing tests (30 mA/85 °C/1500 h), confirm a 65% drop of optical power and an increase of one decade of leakage current spreading at the silicone oil/chip interfaces. Through measurements of silicone coating fluorescence emission spectra, we demonstrate that the polymer enlarges the LED emission spectrum and shifts central wavelength. This shift is related to silicone oil spectral instability and the central wavelength of packaged LED appears to be temperature insensitive. In this paper, we discriminate the degradation of bulk silicone oil responsible for optical losses from the polymer/chip interface inducing larger leakage current

Statistics on tuna surface fishery¿s bycatch landed in Abidjan, Côte d¿Ivoire, for the 1982-2009 period

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