The stimulation of the modern transformation processes by the church and the opportunity this presents to industrial mission

The church had reacted to both political and industrial change. Localised theology was the answer to a restricted political dispensation, and the final result was the application of liberation theology. The Kairos Document, the Evangelical Witness, the Belhar Confession and Church and Society express the different churches’ viewpoints about the apartheid regime. This contextual focus on the same political dispensation unleashed church influence during the establishment of a national democratic dispensation. The different efforts to deal with industrial change by means of church renewal have finally paved the way for the development of a new industrial mission, vision and approach. This has resulted in the forming of an interchurch industrial organisation, and far-reaching possibilities within the industrial environment.http://www.hts.org.zaam201

Analyse de front d'onde sur étoiles laser pour les extremely large telescopes

Afin d'étendre la couverture du ciel en Optique Adaptative (OA), des Etoiles Guide Laser (EGL) sont crées artificiellement dans la couche de Sodium de l'atmosphère. Leur utilisation provoque des problèmes spécifiques sur la mesure de front d'onde par l'Analyseur de Surface d'Onde (ASO). Certains deviennent critiques avec le passage aux ELT (Extremely Large Télescopes). L'objectif de cette thèse est d'étudier la spécificité de l'analyse de front d'onde sur EGL pour les ELT, et d'optimiser l'ASO dans ce cadre. Pour cela, une caractérisation des effets d'anisoplanétisme focal différentiel sur la mesure de front d'onde a d'abord été effectuée. En s'appuyant sur un modèle de propagation diffractive, nous avons chiffré l'impact des effets de phase et d'amplitude dans le cas des ELT en prenant en compte l'étape de reconstruction tomographique. Nous avons montré que ces effets étaient d'amplitude faible pour la plupart des applications. Nous avons ensuite proposé un modèle simple pour classer les différentes sources d'erreurs mises en évidence dans la littérature. Après avoir montré que l'ASO Pyramide et l'ASO Shack-Hartmann (SH) avaient des comportements très proches lors de la mesure sur EGL, nous avons évalué ces différentes sources d'erreur en considérant le cas d'un ASO SH. Nous avons étudié en détail l'évaluation des erreurs de non-linéarités de mesure, puis nous avons évalué l'impact des variations de la couche de Sodium. Notre travail intègre l'étape de reconstruction tomographique. Nous avons pu déduire de ces études les paramètres à privilégier dans le dimensionnement de l'ASO, afin d'optimiser la mesure de front d'onde sur EGL pour un ELT.In order to increase the sky coverage in Adaptive Optics (AO), Laser Guide Stars (LOS) are created in the Sodium layer of the atmosphere. These 3D extended objects induce specific problems on the wave front measurement performed by the Wave Front Sensor (WFS). Some of these problems become critical on the Extremely Large Telescopes (ELTs). The goal of this work is to study the specificity of the wavefront analysis on LGS in the framework of the ELTs, and to optimize the WFS measurement accuracy on such objects. We first studied the characterization of the effects of differential focal anisoplanatism on wave front measurements. Using a diffractive propagation model,i.e. taking into account the effects of phase and amplitude, we have calculated these effects in the case of ELTs.considering the stage of tomographic phase reconstruction. We have shown that these effects are actually low in amplitude for most applications. We proposed then a simple model to classify the different sources of errors identified in the literature. After showing that the Pyramid WFS and the Shack-Hartmann (SH) had very similar behaviours with regards to these effects, we assessed the différent error terms in the decomposition, considering the case of a SH WFS. We studied in detail the evaluation of the non-linearity error and the sensor noise error. Then we evaluated the impact of the Sodium layer variations, considering analytical profiles as well as real data. We considered also here the stage of tomographic reconstruction. Finally, we managed to deduce from this study the parameters of the WFS to be favored when optimizing the wavefront analysis on LGS, in the case of ELTs.PARIS7-Bibliothèque centrale (751132105) / SudocSudocFranceF

Differential focal anisoplanatism in laser guide star wavefront sensing on extremely large telescopes

International audienc

Wavefront sensing with laser guide stars on the ELTs

International audienc

Anisoplanatism effects in Shack-Hartmann Wave Front Sensing with Laser Guide Stars on the ELTs

Laser Guide Stars aim at increasing the sky coverage, highly restricted when using Adaptive Optics with Natural Guide Stars. With such an artificial object, spot elongation may be a limitation for the measurement quality when using a Wave Front Sensor. In this document, we evaluate and discuss the effects of this limitation on wave front measurements, for a 40 m class telescope. We also explore the possibilities of taking these effects into account in the wave front reconstruction

Greater diversity of HIV DNA variants in the rectum compared to variants in the blood in patients without HAART

International audienceThe gut-associated lymphoid tissue represents the largest reservoir of HIV-1. Improving knowledge of this reservoir by studying the diversity of viral population is a key step towards understanding the pathogenesis and dynamics of HIV. Obtaining samples is difficult and little information is available on gut viral quasispecies during the course of infection in humans. The aim of the study was to characterize rectal viral strains and their diversity and to investigate the relationships between the rectal tissue reservoir and viral variants in the blood. Phylogenetic analyses were performed on the env sequences for rectal HIV DNA, blood HIV DNA and HIV RNA clones, with maximum likelihood and neighbor-joining methods on seven patients. Genetic diversity was assessed. Higher diversity of HIV DNA clones was noted in the rectum compared to blood in 4 out of 5 patients without HAART. Viral diversity was present in the rectum from time of the primary infection. Similar degrees of diversity were observed in the rectum and blood during HAART. Rectal and blood HIV variants were interspersed partially or totally in the seven patients. A certain number of rectal HIV DNA clones were clustered together in six patients. These results suggest that variants in the rectum were more heterogeneous than variants in the blood from patients without HAART, probably because the activated milieu of gut-associated lymphoid tissue may provide an improved environment for viral replication, and indicate exchange of viral populations between blood and rectal tissues, reflecting the dynamics of HIV during course of infection

Forêts françaises en crise : nature, climat, société. Analyse et propositions des ONG de conservation de la nature

International audienceThe six conservation NGOs that wrote this article present their arguments for an evolution of the French forest policy. Their arguments are based on 5 main principles for the management of forest commons, i.e. 1) ensure a multifunctional management valuing all the ecological services of forests, 2) place biodiversity at the heart of forest policies to adapt management more easily, 3) be more aware of societal expectations in order tobetter meet them, 4) enable forests and foresters to fully respond to the unprecedented challenges of the climate crisis, and 5) integrate forests into land planning as a green infrastructure of the economy. Then, the six NGOs recommend a general political orientation basing any forestry policy on the constitutional environmental charter of 2004, and they propose 21 structural or operational measures.Les six ONG de conservation de la nature auteures de cet article proposent leur argumentaire pour une évolution de la politique forestière nationale. Celui-ci est fondé suivant cinq grands principes de gestion du bien commun que sont les forêts : 1. Assurer une gestion multifonctionnelle valorisant tous les services écologiques des forêts ; 2. Mettre la biodiversité au coeur de la politique forestière pour faciliter l’adaptation de la gestion ; 3. Accroître l’écoute des attentes de la société, pour mieux y répondre ; 4. Mettre forêts et forestiers en capacité de répondre pleinement aux enjeux inédits de la crise climatique ; 5. Insérer les forêts dans l’aménagement du territoire comme infrastructure verte de l’économie. Ensuite, les six ONG recommandent une orientation politique générale consistant à fonder toute politique forestière sur la charte constitutionnelle de l’environnement de 2004 et proposent 21 mesures structurelles ou opérationnelles