Synthesis of 3,5-Disubstituted 1,2-Dioxolanes through the Use of Acetoxy Peroxyacetals

International audienceThe synthesis of acetoxy-endoperoxyacetal derivatives allowed the formation of functionalized 3,5-disubstituted-1,2-dioxolanes through the formation of reactive peroxycarbenium species under Lewis acid mediation. The introduction of a neutral nucleophile such as allylsilanes, silanes, or silyl enol ethers was accomplished with moderate to good yields. The two studied Lewis acids, TiCl4 and SnCl4, gave contrasted results. The higher diastereoselectivity towards the trans diastereomer in experiments with TiCl4 as Lewis acid was explained by a faster degradation of the cis isomer product, conducting generally to lower yields. A rationalization of this result was supported by calculation

Contribution de l'ingénierie dirigée par les modèles à la conception de modèles grande culture

Cette thèse, à caractère industriel, vise à répondre à une problématique de production de l entreprise ITK. Par la mise en oeuvre des techniques de l ingénierie dirigée par les modèles, nous proposons un environnement de modélisation et de simulation pour la croissance des plantes. Outre sa facilité d utilisation pour les agronomes, le prototype obtenu permet la génération automatique de code Java des modèles à intégrer dans des outils d aide à la décision exécutés sur une plateforme Java Enterprise Edition.This PhD thesis has an industrial purpose. It is motivated by a software production issue met within the ITK company. Using the techniques provided by model-driven engineering, we propose a modeling and simulation environment dedicated to plant growth. The prototype achieved proves to be easy to use for crop modelers. It is also enhanced with a Java code generation feature. The models obtained from this code generation are designed to be integrated into decision support systems running on a Java Entreprise Edition platform.CLERMONT FD-Bib.électronique (631139902) / SudocSudocFranceF

Où sont les femmes dans les mémoires militaires français du xvie siècle ?

« L’Histoire sans les femmes est-elle possible ? », se demandait il y a vingt ans un collectif de chercheuses et de chercheurs en sciences sociales. Il semble que la question ne se soit guère posée aux gentilshommes français qui écrivaient au xvie siècle les récits de leurs expériences militaires. Quand il ouvre ses Commentaires, imprimés à Bordeaux en 1592 et dans lesquels il retrace les tribulations de sa longue carrière militaire, le vieux maréchal gascon Blaise de Monluc donne quatre cons..

"Imprimer en nostre souvenance": Enjeux et pratiques de la mémoire et de l'oubli à la Renaissance

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Domain-Specific Modeling for a Crop Model Factory

In the context of crop model design for industrial purposes, this paper proposes a domain-specific modeling approach to provide a crop model factory for the modelers in agronomy. The authors’ approach proposes to separate the concerns of representing the simulation process (process-based dynamics) and the plant data structure. They propose a refined and stabilized metamodel for the dynamics based on past preliminary work. This paper also explains how the Model-View-Controller design pattern can be applied to DSML environments to produce a more specialist-friendly interface. In addition, the authors propose a metamodeling usage of the Model-View-Controller offering the potential to develop a DSML for DSMLs design

Conception semi automatique de cubes de données spatiales à partir de résultants de modèles de simulation

International audienceIn this paper we present a semi-automatic method for designing and generating spatial data cubes in order to visualize and analyze the results of simulation models. In our approach users choose their fact of analysis, then the system derives automatically a set of possible measures, dimensions of analysis, and generates the corresponding spatial data cubes. The analysis and visualization of the spatial data cubes are carried out using appropriate SOLAP tools. We also present the SimOLAP system, developed to validate our approach

Magnesium promoted autocatalytic dehydrogenation of amine borane complexes: A reliable, non-cryogenic, scalable access to boronic acids

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Continuous movement behavior of humpback whales during the breeding season in the southwest Indian Ocean: on the road again!

Abstract Background Humpback whales are known to undertake long-distance migration between feeding and breeding sites, but their movement behavior within their breeding range is still poorly known. Satellite telemetry was used to investigate movement of humpback whales during the breeding season and provide further understanding of the breeding ecology and sub-population connectivity within the southwest Indian Ocean (SWIO). Implantable Argos satellite tags were deployed on 15 whales (7 males and 6 females) during the peak of the breeding season in Reunion Island. A switching-state-space model was applied to the telemetry data, in order to discriminate between “transiting” and “localized” movements, the latter of which relates to meandering behavior within putative breeding habitats, and a kernel density analysis was used to assess the spatial scale of the main putative breeding sites. Results Whales were tracked for up to 71 days from 31/07/2013 to 16/10/2013. The mean transmission duration was 25.7 days and the mean distance travelled was 2125.8 km. The tracks showed consistent movement of whales from Reunion to Madagascar, demonstrating a high level of connectivity between the two sub-regions, and the use of yet unknown breeding sites such as underwater seamounts (La Perouse) and banks (Mascarene Plateau). A localized movement pattern occurred in distinct bouts along the tracks, suggesting that whales were involved in breeding activity for 4.3 consecutive days on average, after which they resume transiting for an average of 6.6 days. Males visited several breeding sites within the SWIO, suggesting for the first time a movement strategy at a basin scale to maximize mating. Unexpectedly, females with calf also showed extensive transiting movement, while they engaged in localized behavior mainly off Reunion and Sainte-Marie (East Madagascar). Conclusions The results indicated that whales from Reunion do not represent a discrete population. Discrete breeding sites were identified, thereby highlighting priority areas for conservation. The study is a first attempt to quantify movement of humpback whales within the southwestern Indian Ocean breeding range. We demonstrate a wandering behavior with stopovers at areas that likely represent key breeding habitat, a strategy which may enhance likelihood of individual reproductive success

Beta-nerve growth factor stimulates spontaneous electrical activity of in vitro embryonic mouse GnRH neurons through a P75 mediated-mechanism

International audienceThe control of ovulation helps guarantee the success of reproduction and as such, contributes to the fitness of a species. In mammals, two types of ovulation are observed: induced and spontaneous ovulation. Recent work on camelids, that are induced ovulators, highlighted the role of a factor present in seminal plasma, beta Nerve Growth Factor (β-NGF), as the factor that triggers ovulation in a GnRH dependent manner. In the present work, we characterized alpaca β-NGF (aβ-NGF) and its 3D structure and compared it with human recombinant β-NGF (hβ-NGF). We showed that the β-NGF enriched fraction of alpaca semen and the human recombinant protein, both stimulated spontaneous electrical activity of primary GnRH neurons derived from mouse embryonic olfactory placodes. This effect was dose-dependent and mediated by p75 receptor signaling. P75 receptors were found expressed in vitro by olfactory ensheathing cells (OEC) in close association with GnRH neurons and in vivo by tanycytes in close vicinity to GnRH fibers in adult mouse. Altogether, these results suggested that β-NGF induced ovulation through an increase in GnRH secretion provoked by a glial dependent P75 mediated mechanism