Control of the cell cycle during meiotic maturation of mouse oocytes

The overall aim of the work presented in this thesis is to better understand the molecular mechanisms underlying the progression of the meiotic division in mammalian oocytes. The first goal of this project was to investigate the relative contribution of securin and cyclin B1 to the control of the protease separase during the indeterminate period of metaphase II arrest. I found here that although there are conditions in which either securin or MPF can prevent chromosome disjunction, such as during meiosis I, securin is the predominant inhibitor of separase during metaphase II arrest. Thus, CDK1 pharmacological inhibition as well as antibody inhibition of CDK1/cyclin B1 binding to separase, both failed to induce sister chromatid disjunction. Instead, securin morpholino knockdown induced sister chromatid separation, which could be rescued by injection of securin cRNA. I also examined the effect of CDK1 and MAPK activities on securin stability. Inhibition of both kinases, but not either one alone, using roscovitine and UO126, induced the premature destruction of securin during prometaphase of meiosis I. However, this effect is not dependent on securin phosphorylation, given that mutagenesis of CDK1 and MAPK phosphorylation sites on securin did not affect its stability. Finally, I found that CDK1 and MAPK inhibition also causes the premature degradation of other APC/C substrates, such as cyclin B1 and geminin. Interestingly, only the D-box containing substrates and not Ken-box substrates were subject to such effect. However, this prometaphase I instability of the D-box substrates was apparently not mediated by APC/CCdc20 or APC/CCdh1, given that Cdc20 was also targeted for destruction and morpholino-knockdown of both Cdc20 and Cdh1 failed to rescue securin stability. Also, the inhibition of SCFβ-TrCP using the dominant negative mutant of its F-box protein (β-TrCPΔ) could not restore securin levels, suggesting it is not SCFβ-TrCP-dependent. Future work will explore whether this effect could be attributed to activation of some meiosis-specific APC/C co-activators or the core APC/C, which was recently reported of being able to directly interact with the D-box containing substrates independently of Cdc20 and Cdh1 (Passmore et al., 2003; Yamano et al., 2004)

Effect of some Pseudomonas strains and Agave americana L. on wheat germination under salt stress

Currently, several efforts focus remedying the problem of agricultural soil salinity using eco-friendly strategies. This study aimed particularly the study of Triticum durum (durum wheat) seeds germination in the presence of Pseudomonas strains and hydro-alcoholic extract of Agave americana L. under saline stress conditions. The preliminary phytochemical screening of A. americana, phylogenetic identification and production of indole-3-acetic acid (IAA) by Pseudomonas strains, in vitro impact of hydro-alcoholic extract and Pseudomonas strains combination on salt stress resistance, preliminary effects of A. americana on Triticum durum germination and phytopathogenic fungi inhibition under salt stress were carried out using corresponding protocols. In in vitro trials, phytochemical screening revealed the richness of A. americana in polyphenols (1014.062±161.017 mM GA equivalent/g FW) and flavonoids (51.065±27.391 mg quercetin equivalent/g FW). The ability of Pseudomonas strains to produce the phytohormone indole-3-acetic acid (IAA) varied from 116.67±8.25 µg/ml to 857.14±80.50 µg/ml. The leaf extract of A. americana is an effective osmoprotectant that improves the resistance of the strain P1 Pseudomonas plecoglissicida to saline stress. In in vivo experiments, the extract of A. americana did not show any effect on the germination of wheat seeds. However, it effectively inhibited the contamination of seeds by phytopathogenic fungi during germination and saline conditions. Findings of the study revealed that Pseudomonas plecoglissicida and A. americana extract are very promising for the inhibition of phytopathogenic fungi and the alleviation of salt stress

Direct Power Control for AC/DC/ACConverters in Doubly Fed Induction Generators Based Wind Turbine

In this paper direct power control (DPC) strategy is applied to control a doubly fed induction generator (DFIG) based wind energy generation system. A three level NPC ac/dc/ac converter is controlled by direct power control method. The rotor side converter is controlled by a novelle switching table based a double active power hysteresis band method. The selects appropriates voltage vector based on the instantaneous errors between the reference and estimated values of active and reactive powers and rotor flux position. Also the grid side is controlled by direct power control based a grid voltage position to ensures a constant DC voltage, Simulation results on a demonstrate robust, precise, and fast dynamic behavior of system.DOI:http://dx.doi.org/10.11591/ijece.v2i3.284

Quelle didactique pour l’enseignement / apprentissage de la langue amazighe?

Mon propos porte sur les aspects didactiques de l’enseignement /apprentissage de la langue amazighe. Plus précisément, il est question des méthodes utilisées depuis l’introduction de cette langue dans le système éducatif. Il n’est pas nécessaire de s’appesantir sur les aspects sociolinguistiques qui caractérisent cette langue et qui constituent des « travers1 » pour les praticiens en charge de cet enseignement car « cette langue est non aménagée et éclatée en dialectes2 » dont chacun d’eux a le statut de langue maternelle dans son aire géographique qui lui est propre. Face à cette situation inédite dans l’institution scolaire, de nombreuses questions assez délicates ont alors surgi. Quelle variante enseignée et dans quelle région ? Avec quels outils didactiques ? Avec quels contenus ? Quelle méthode choisir ? Et quelle graphie utilisée

Le mussem de Meknès. Le déclin d’une tradition spirituelle

RésuméLes mussem-s sont des fêtes saisonnières, à la fois foires et pèlerinages célébrés aux environs du sanctuaire d’un saint personnage. Au Maroc, lors des festivités annuelles célébrant le jour de la naissance du prophète Muhammad, le Palais royal organise à Meknès le mussem du Chaykh al-Kâmil, censé représenter le pèlerinage des disciples de la confrérie soufie des Aïssâwa. Cet article décrit et analyse l’organisation et le fonctionnement de ce mussem dans le champ culturel et religieux du Maroc. Les données de l’auteur proviennent d’une enquête de terrain menée auprès du public pèlerin, des membres de la confrérie des Aïssâwa, des hauts responsables de l’ordre religieux et des autorités publiques. Par une approche socio-anthropologique et historique, le but est de saisir la signification et les enjeux de ce mussem dans la société marocaine contemporaine pour conclure sur son déclin depuis les années 1980.The mussem of Meknès : The Decline of a Spiritual TraditionAbstractThe mussem-s are seasonal festivals, both celebrated pilgrimages and fairs around the shrine of a holy man. In Morocco, during the annual festivities celebrating the day of birth of the prophet Muhammad, the government organizes in Meknès the mussem of the Shaykh al-Kamil, the pilgrimage for the members of the sufi brotherhood of Aïssâwa. This article describes and analyzes the organization and the functioning of this mussem in the field of culture and religion of Morocco. The Data of the author comes from an investigation conducted among the pilgrim audience, members of the brotherhood of Aïssâwa, senior officials of the religious order and public authorities. With a socio-anthropological and historical approach, the goal is to capture the meaning and the implications of this mussem in contemporary Moroccan society to conclude on the wane since the 80’s

Des soufis en banlieue parisienne

Cet article décrit et analyse l’organisation et le fonctionnement d’une zāwiya française de la confrérie soufie marocaine Qâdiriyya-Bûdchichiyya. Les données de l’auteur proviennent de l’observation participante, d’entretiens libres et semi-directifs appliqués à une enquête de terrain à l’intérieur de l’une des zāwiya-s de cette confrérie située en banlieue parisienne. Par une approche microsociologique, le but est de saisir, d’une part, les modalités selon lesquelles une confrérie maghrébine contemporaine s’implante en France, et, d’autre part, ce que la doctrine mystique représente aux yeux d’adeptes vivant dans une société laïque de tradition catholique.This article is a microsociological study of a French zāwiya of the Moroccan soufi brotherhood Qâdiriyya-Bûdshishiyya. The data of the author come from the participating observation, of free and semi-directing interviews applied to an investigation inside one of the zāwiya-s of the brotherhood located in Parisian suburbs. The aim is to discover how a contemporary North-African brotherhood takes root in France and what the mystical doctrine represents for the disciples who lives in a secular society of catholic tradition.Este artículo describe y analiza la organización y el funcionamiento de una zâwiya francesa de la cofradía sufi marroquí Qâdiriyya-Bûdshishiyya. Los datos del autor provienen de la observación participante, de entrevistas abiertas y semi-dirigidas aplicadas a una investigación de campo de tres semanas (febrero de 2004) dentro de una de las zâwiya-s de esta cofradía situada en la periferia de Paris. Desde un enfoque microsociológico, el objetivo es comprender, por un lado, las modalidades a través de las cuales una cofradía magrebí contemporánea se implanta en Francia, y, por otro lado, lo que la doctrina mística representa a los ojos de adeptos que viven en una sociedad laica de tradición católica

Analyse du manuel de langue amazighe de 7e A.F.

Je me propose d’analyser le nouveau manuel de langueamazighe destiné aux apprenants de 7 année. Mon analyse seracentrée aussi bien sur les contenus linguistiques que sur lessoubassements des choix sociolinguistiques et didactiques. Pour ce faire, je commencerai par dresser un état des lieux pour mieux situer le public visé puis je procéderai à un rapide descriptif avant de passer à l’analyse proprement dite