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Conçu pour les étudiants en Master MEEF (Métiers de l’Enseignement, de l’Éducation et de la Formation), les candidats libres et en formation privée, cet ouvrage propose une préparation complète à l’épreuve orale d’admission de français du CRPE (concours de recrutement des professeurs des écoles).

Resumen: El pénfigo es una enfermedad autoinmune poco frecuente que afecta piel y mucosas. La lesión fundamental es la flictena debida a la acantolisis por el depósito de anticuerpos IgG contra glicoproteínas de los desmosomas. En el neonato esta afectación se atribuye al pasaje pasivo de anticuerpos (IgG) maternos a través de la placenta. El pénfigo vulgar y foliáceo son los subtipos más frecuentes en el recién nacido (RN). Se reporta el caso de un RN con pénfigo vulgar neonatal, que evoluciona a la remisión completa de las lesiones ampollares, sin mediar tratamiento inmunosupresor. Summary: Pemphigus is a rare autoimmune disease that affects skin and mucous membranes. The main lesions result from acantholysis caused by IgG antibody deposits on the desmosomes’ glycoproteins. In newborns, it is caused by the passive passage of maternal antibodies (IgG) through the placenta. The most frequent pemphigus subtypes in newborns are pemphigus vulgaris and foliaceus. This is a case report of a neonatal pemphigus vulgaris, which evolved to a full remission of the bullous lesions, without the need immunosuppressive treatment. Resumo: O pênfigo é uma doença autoimune rara que afeta a pele e as membranas mucosas. A principais lesões são bolhas causada pela acantólise resultado dos depósitos de anticorpos IgG nas glicoproteínas dos desmossomos. Em recém-nascidos, é causado pela passagem passiva de anticorpos maternos (IgG) através da placenta. Os subtipos de pênfigo mais frequentes em recém-nascidos são pênfigo vulgar e foliáceo. Este é um relato de caso de um pênfigo vulgar neonatal, que evoluiu para uma remissão completa das lesões bolhosas, sem a necessidade de tratamento imunossupressor.

In the field of the inertial confinement fusion ( ICF), the equation of state ( EoS) of the hydrogen and its isotopes is one of the most important properties to know. The EoS based on chemical models have difficulty in giving an unambiguous description of the hydrogen in the strong coupled and partial degenerate regime, called Warm Dense Matter ( WDM). Indeed, these models use potential with adjustable parameters to describe the many body interactions which are important in the WDM. On the other hand, the ab initio methods resolve almost exactly the quantum many body problem and are thus particularly relevant in this domain. In the first part of this thesis, we describe how we built a table of a multi-phase EoS of the hydrogen, using ab initio methods in the field of the WDM. We show in particular that this EoS is in very good agreement with most of the available experimental data (principal Hugoniot, sound velocity in the molecular fluid, melting curve at low pressure, measurements of multiple shocks). In the second part, we present a direct application of our EoS by showing its influence on the criteria of ignition and combustion of two target designs for ICF: a self-ignited target which will be used on the Laser MegaJoule ( LMJ), and a shock-ignited target. We show in particular that the optimization of the laser pulse allowing maximizing the thermonuclear energy is strongly dependent on the precision of the EoS in the strong coupled and degenerate domain., Dans le domaine de la fusion par confinement inertiel (FCI), l'équation d'état (EoS) de l'hydrogène et de ses isotopes est très certainement une des propriétés les plus importantes à connaître. Les EoS basées sur des modèles chimiques peinent à donner une description univoque de l'hydrogène dans le domaine de couplage et de dégénérescence partiels, appelé matière dense et tiède, ou Warm Dense Matter (WDM). En effets, ces modèles utilisent des potentiels ad hoc pour décrire les interactions à N corps dont les effets sont importants dans la WDM. Au contraire, les méthodes de calcul ab initio s'affranchissent de ces approximations en résolvant de manière exacte (ou presque) le problème quantique à N corps et sont donc particulièrement pertinentes dans ce domaine. Dans la première partie de cette thèse, nous décrivons comment nous avons construit une table d'EoS multi-phase de l'hydrogène, à partir de méthodes de calcul ab initio dans le domaine de la WDM. Nous montrons notamment que cette EoS est en très bon accord avec la plupart des données expérimentales disponibles (Hugoniot principale, vitesse du son dans le fluide moléculaire, courbe de fusion à basse pression, mesures de chocs multiples). Dans la deuxième partie, nous présentons une application directe de notre EoS en montrant son influence sur les critères d'allumage et de combustion de deux types de cibles pour la FCI : une cible auto-allumante qui sera utilisée sur le Laser MegaJoule (LMJ), et une cible destinée à l'allumage par choc. Nous montrons notamment que l'optimisation de l'impulsion laser permettant de maximiser l'énergie thermonucléaire dégagée par les cibles est fortement dépendante de la précision de l'EoS dans le domaine de couplage et de dégénérescence forts.

In the field of the inertial confinement fusion ( ICF), the equation of state ( EoS) of the hydrogen and its isotopes is one of the most important properties to know. The EoS based on chemical models have difficulty in giving an unambiguous description of the hydrogen in the strong coupled and partial degenerate regime, called Warm Dense Matter ( WDM). Indeed, these models use potential with adjustable parameters to describe the many body interactions which are important in the WDM. On the other hand, the ab initio methods resolve almost exactly the quantum many body problem and are thus particularly relevant in this domain. In the first part of this thesis, we describe how we built a table of a multi-phase EoS of the hydrogen, using ab initio methods in the field of the WDM. We show in particular that this EoS is in very good agreement with most of the available experimental data (principal Hugoniot, sound velocity in the molecular fluid, melting curve at low pressure, measurements of multiple shocks). In the second part, we present a direct application of our EoS by showing its influence on the criteria of ignition and combustion of two target designs for ICF: a self-ignited target which will be used on the Laser MegaJoule ( LMJ), and a shock-ignited target. We show in particular that the optimization of the laser pulse allowing maximizing the thermonuclear energy is strongly dependent on the precision of the EoS in the strong coupled and degenerate domain., Dans le domaine de la fusion par confinement inertiel (FCI), l'équation d'état (EoS) de l'hydrogène et de ses isotopes est très certainement une des propriétés les plus importantes à connaître. Les EoS basées sur des modèles chimiques peinent à donner une description univoque de l'hydrogène dans le domaine de couplage et de dégénérescence partiels, appelé matière dense et tiède, ou Warm Dense Matter (WDM). En effets, ces modèles utilisent des potentiels ad hoc pour décrire les interactions à N corps dont les effets sont importants dans la WDM. Au contraire, les méthodes de calcul ab initio s'affranchissent de ces approximations en résolvant de manière exacte (ou presque) le problème quantique à N corps et sont donc particulièrement pertinentes dans ce domaine. Dans la première partie de cette thèse, nous décrivons comment nous avons construit une table d'EoS multi-phase de l'hydrogène, à partir de méthodes de calcul ab initio dans le domaine de la WDM. Nous montrons notamment que cette EoS est en très bon accord avec la plupart des données expérimentales disponibles (Hugoniot principale, vitesse du son dans le fluide moléculaire, courbe de fusion à basse pression, mesures de chocs multiples). Dans la deuxième partie, nous présentons une application directe de notre EoS en montrant son influence sur les critères d'allumage et de combustion de deux types de cibles pour la FCI : une cible auto-allumante qui sera utilisée sur le Laser MegaJoule (LMJ), et une cible destinée à l'allumage par choc. Nous montrons notamment que l'optimisation de l'impulsion laser permettant de maximiser l'énergie thermonucléaire dégagée par les cibles est fortement dépendante de la précision de l'EoS dans le domaine de couplage et de dégénérescence forts.

In this work, we are interested in solute transport in fissured porous media. The medium is considered as a special case of a two-region system, and a two-equation model previously obtained from a volume averaging technique is used to derive large-scale dispersion coefficients. These coefficients are obtained as solutions of a set of closure problems and the main objective of this work is to present an efficient method to solve these closure problems. The method makes use of an unstructured grid and special techniques to take into account the fissure network. Results are compared with other existing methods on simple fissured media. Finally, the technique is applied to a complex structure.

A new and stereoselective synthesis is described as an easy route to ostopanic acid using a versatile reagent : (2E,4E)-5-bromopentadienal.

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Improving the description of the equation of state (EoS) of deuterium-tritium (DT) has recently been shown to change significantly the gain of an Inertial Confinement Fusion (ICF) target (Hu et al., PRL 104, 235003 (2010)). We use here an advanced multi-phase equation of state (EoS), based on ab initio calculations, to perform a full optimization of the laser pulse shape with hydrodynamic simulations starting from 19 K in DT ice. The thermonuclear gain is shown to be a robust estimate over possible uncertainties of the EoS. Two different target designs are discussed, for shock ignition and self-ignition. In the first case, the areal density and thermonuclear energy can be recovered by slightly increasing the laser energy. In the second case, a lower in-flight adiabat is needed, leading to a significant delay (3ns) in the shock timing of the implosion., 4 pages, 8 figures

We construct a multiphase equation of state (EoS) of hydrogen in the range 0.2 to 5 g/cc and up to 10 eV based on ab initio electronic structure calculations. In the molecular solid, cold curve and phonon spectra calculations are performed for various structures, proposed in the literature, to cover the stability field up to 500 GPa. A weak structural dependence is observed, and the solid EoS is averaged over these data. In the dissociating molecular fluid and in the dense plasma, calculations are made to complete the abundant data set in the literature. Two physical models are used to fit these calculations: a double-Debye model for the solid phase and a one-component plasma model with a mass action law for dissociation to implicitly access the molecular phase in the fluid state. The output of the calculations; energy, pressure, temperature, and density are perfectly reproduced with thermodynamical consistency. This model also allows us to access to the total free energy. The ionic quantum zero-point contribution is taken into account. The present hydrogen EoS is shown to reproduce most of the existing experimental data very well: the solid compression curve, the Hugoniot curve, the sound velocity in the molecular fluid, and the melting curve. The usefulness of this EoS is illustrated by the computation of an interesting isotopic shift on the melting curve and of an isentropic compression path reaching temperatures lower than 1000 K in the terapascal range.

Local grid refinement (LGR) is applied in reservoir simulation routinely for structured and unstructured grids and implemented in commercial simulators. It is used to add detail where justified by data availability and to keep a coarse resolution where less data are available. In basin modelling, LGR has not yet been implemented. It could be used in situations where seismic data are available at individual structures or prospects but not elsewhere in kitchen areas or within the sedimentary cover. Even more importantly, for appraisal studies, a data set may be available at reservoir resolution that may have to be integrated with the basin scale to model the impact of basin scale fluid flow on the reservoir. Presently, tartan grids allow to refine the grid in x,y directions but waste a lot of grid cells in areas where refinement is neither necessary nor wanted. Vertical grid refinement is performed where the stratigraphic grid needs to be enriched to model fluid flow. In order to better represent data availability (basin versus prospect/structure of interest) and to save computing time, it is preferable to have a lateral and vertical grid refinement that only treats areas where information is available The BasinLGR project has developed numerical methods that allow to treat two or more imbricated Cartesian grids refining in all three spatial directions with several levels of refinement. Fluid flow is performed on refined grid while thermics remain on the coarse grid. Both kerogen cracking and migration are represented and illustrated on an example displaying the advantages of a LGR model.

Wellbore crossflow can have an important effect on the well production in highly stratified reservoirs. This phenomenon may also appear using EOR techniques or in advanced wells. In those cases, crossflow must be accurately represented and shutting the crossflowing layers may create significant errors on the forecast production and severe numerical problems. This paper describes the method which has been implemented in an all-purpose reservoir simulator. Our method handles both Black Oil and compositional models in a fully implicit scheme. The wells are discretized in different segments where pressure and compositions are determined. These segments generally correspond to the perforated reservoir cells. The wellbore equations are decoupled from the main Newton resolution for CPU time reduction reasons. The characteristic time-scales in the reservoir and the wells are very different, i.e. the well variables vary more rapidly than the reservoir ones. To ensure good simulation times, cheap computations are made on the wells to reach a pseudo steady state prior to the Newton resolution. The crossflow model is used on both vertical and horizontal wells and also multilateral wells. Well control can be managed using the build-in algorithms that have been extended to crossflowing wells. Simulation runs showing the accuracy and reliability of the crossflow modelling are presented. The numerical solution is compared with the results from other studies and with a semi analytical method.

Many studies have proposed one-equation models to represent transport processes in heterogeneous porous media. This approach is based on the assumption that dependent variables such as pressure, temperature, or concentration can be expressed in terms of a single large-scale averaged quantity in regions having very different chemical and/or mechanical properties. However, one can also develop large-scale averaged equations that apply to the distinct regions thatmake up a heterogeneous porousmedium. This approach leads to region-averaged equations that contain traditional convective and dispersive terms, in addition to exchange terms that account for the transfer between the different media. In our approach, the fissures represent one region, and the porous media blocks represent the second region. The analysis leads to upscaled equations having a domain of validity that is clearly identified in terms of time and length-scale constraints. Closure problems are developed that lead to the prediction of the effective coefficients that appear in the region averaged equations, and the main purpose of this article is to provide solutions to those closure problems. The method of solution makes use of an unstructured grid and a joint element method in order to take care of the special characteristics of the fissured network. This new numerical method uses the theory developed by Quintard and Whitaker and is applied on considerably more complex geometries than previously published results. It has been tested for several special cases such as stratified systems and ‘‘sugarbox’’ media, and we have compared our calculations with other computational methods. c © 2000 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 16: 237–263, 2000

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