Effect of El Nino southern oscillation events on the distribution and abundance of phytoplankton in the Western Pacific Tropical Ocean along 165°E

The distribution of physical and chemical parameters and their impact on the biomass and abundance of phytoplankton in the Western Pacific ocean were compared in two opposing situations : the El Nino Southern Oscillation (ENSO) event of 1987 and the no-ENSO period of 1988. During El Nino conditions (september 1987), maximum cell abundance was recorded at 10°S at the boundary between the South Equatorial current (SEC) and the South Equatorial countercurrent (SECC). In September 1988, after the return of non-ENSO conditions, a well-established Equatorial upwelling produced an increase in the surface layer nutrient supply over 7° of latitude. This in turn caused an increase in phytoplankton populations in the upper layer, with chlorophyll concentrations ... Integrated over 120 m, the cyanobacteria and microalgae populations were respectively 4.7. and 3.2 times larger than the year before. On the other hand, transient nutrients inputs such as those observed at 10°S in September 1987 caused a large increase in cyanobacteria populations (4.4. times) compared with those in neighbouring zones, and a somewhat smaller increase in microalgae populations (1.3 times

Herpes simplex virus blocks apoptosis by precluding mitochondrial cytochrome c release independent of caspase activation in infected human epithelial cells

Expression of HSV-1 genes leads to the induction of apoptosis in human epithelial HEp-2 cells but the subsequent synthesis of infected cell protein prevents the process from killing the cells. Thus, viruses unable to produce appropriate prevention factors are apoptotic. We now report that the addition of either a pancaspase inhibitor or caspase-9-specific inhibitor prevented cells infected with an apoptotic HSV-1 virus from undergoing cell death. This result indicated that HSV-1-dependent apoptosis proceeds through the mitochondrial apoptotic pathway. However, the pancaspase inhibitor did not prevent the release of cytochrome c from mitochondria, implying that caspase activation is not required for this induction of cytochrome c release by HSV-1. The release of cytochrome c was first detected at 9 hpi while caspase-9, caspase-3 and PARP processing were detected at 12 hpi. Finally, Bax accumulated at mitochondria during apoptotic, but not wild type HSV-1 infection. Together, these findings indicate that HSV-1 blocks apoptosis by precluding mitochondrial cytochrome c release in a caspase-independent manner and suggest Bax as a target in infected human epithelial cells

Figures de musiciens II - Les inventions de la musique au Moyen Âge

L’atelier sur les « Figures de musiciens au Moyen Âge » en mai 2007 avait inauguré une première rencontre pluridisciplinaire autour des typologies médiévales des « musiciens » et des possibles définitions étymologiques, iconographiques, musicologiques et historiques les désignant selon les usages des figures et des discours, selon leurs finalités et leurs contextes. L’objectif du deuxième atelier, prévu du 17 au 19 juin 2009, vise à perpétrer ce dialogue interdisciplinaire entre musicologues,..

Rights transfers in Madagascar biodiversity policies: achievements and significance

International audienceDecentralization and people's participation have been key features of government environmental policy since the 1990s. In Madagascar, the policy of Secured Local Management of Natural Resources, known as the GELOSE act, has created a framework for the transfer of rights from central government to local communities. This article analyses the practical implementation of this policy by focusing on the nature of the rights transferred and on the nature of the contracts and incentives developed. The Aghion and Tirole model for allocation of formal and real authority in an organization is used to shed light on the contractual definition process and on the trade-offs between giving responsibilities to local communities and losing control over natural resources management. It is shown that a congruence of interests between the parties is crucial for effective delegation of authority to local communities and that this congruence may emerge in relation to the transfer of exclusion right