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Approche de synthèse du tricycle ABC du taxol. Stéphanie Schiltz Le taxol est un composé découvert en 1965 à partir d'un extrait d'if du Pacifique (Taxus Brevifolia Nutt.). Son mode d'action original et inconnu au moment de sa découverte a fait de cette molécule une référence en matière de traitement anti-cancéreux. La présence de nombreuses fonctionnalités oxygénées, le nombre élevé de centres asymétriques et surtout sa structure tétracyclique comportant de plus un cycle à huit chaînons ont suscité l'intérêt des chercheurs depuis sa publication. Découverte dans les années 1970, la réaction de métathèse cyclisante des oléfines est un outil synthétique extrêmement puissant permettant la préparation de cycles de diverses tailles. Cette étude envisage l'utilisation de cette réaction pour préparer le cycle à huit chaînons du taxol. La première rétrosynthèse étudiée se fonde sur la fermeture du cycle B à huit chaînons par une réaction de métathèse cyclisante entre les carbones C9 et C10. La première étape de ce travail est consacrée à la préparation des précurseurs de métathèse. Un travail d'optimisation des conditions ne nous a cependant pas permis d'obtenir les diènes souhaités, par réaction de Shapiro ou de Nozaki-Hiyama-Kishi. Une nouvelle stratégie est ensuite étudiée: la fermeture du cycle B s'envisage cette fois-ci entre les carbones C10 et C11. Le diène souhaité serait obtenu par une réaction d'addition nucléophile entre le précurseur linéaire du cycle A et le cycle C. Ces deux précurseurs sont tout d'abord préparés par des méthodes rapides, simples et efficaces, donnant accès à des composés énantiomériquement purs. Les réactions d'additions nucléophiles sont ensuite étudiées. Une optimisation des paramètres permet d'obtenir le composé souhaité sous la forme d'un mélange 1:1 de deux diastéréoisomères, qui sont séparés à l'étape suivante. L'étude des figures de diffraction aux rayons X de ces deux composés permet d'attribuer la configuration relative de chaque centre asymétrique. Les composés obtenus sont ensuite transformés en quelques étapes en précurseurs de métathèse. Le diastéréoisomère comportant la mauvaise stéréochimie pour la sythèse du taxol se dégrade en présence du catalyseur de métathèse. En revanche, le diastéréoisomère comportant la bonne stéréochimie pour la sythèse du taxol cyclise en quelques heures en présence de catalyseur de Grubbs II pour donner le cyclooctène cis. De plus, en présence de catalyseur de Grubbs I, l'obtention d'un mélange des cyclooctènes cis et trans est mise en évidence. Enfin, une étude menée en annexe démontre la possibilité d'introduire la fonctionnalité oxygénée manquante sur le cycle C en utilisant comme produit de départ la cétone de Wieland-Miescher.

Nouvelles applications de la chimie radicalaire des xanthates : Synthèse de molécules organofluorées, de cyanodiènes et δ-lactones insaturées, et d'hétérocycles variés. Lucie Tournier La chimie radicalaire connaît depuis une vingtaine d'années un succès grandissant et ses applications en synthèse organique sont devenues fréquentes. La désoxygénation de Barton et la réduction de dérivés halogénés par l'hydrure de tributylétain ont ouvert la voie à toute une classe de réactions de modification sélective de groupes fonctionnels. Depuis quelques années, les recherches menées au laboratoire sont centrées sur les applications possibles de la chimie radicalaire dans le domaine des réactions intermoléculaires, notamment grâce à la chimie radicalaire des xanthates. Ces composés donnent en effet des résultats particulièrement intéressants dans le cas des réactions d'addition intermoléculaire entre des radicaux carbonés et des oléfines de caractères variées. C'est dans ce cadre que se situent les travaux présentés dans ce manuscrit. L'objectif de ces études a été de développer une série de réactions applicables en synthèse organique. Toutes ces réactions ont pour particularité d'utiliser les xanthates comme source de radicaux. L'organisation du manuscrit est faite de la manière suivante : Dans une première partie, nous présenterons la chimie radicalaire des xanthates développée au laboratoire. Après une brève introduction sur la chimie radicalaire, nous nous attacherons à la particularité de la fonction xanthate, les synthèses possibles de ce type de composés, et les réalisations utilisant cette méthode. Mes travaux effectués sous la direction du Professeur Samir Zard, en collaboration avec Monsieur Jean-Marc Paris et Monsieur François Metz de la société Rhodia, sont centrés sur l'étude de nouveaux radicaux générés par des xanthates, chaque étude présentant un grand nombre d'applications variées. L'exposé de nos travaux portera en premier lieu sur l'étude de xanthates trifluorométhylés. Nous montrerons comment ils permettent d'offrir un accès facile à des composés fluorés particulièrement utiles, notamment dans l'industrie pharmaceutique (Partie 2). Par la suite, nous présenterons la formation de nouveaux radicaux issus d'aldéhydes. Cette méthode ouvre un nouvel accès aux cyanodiènes et δ-lactones insaturées, et offre des solutions inédites pour la synthèse organique (Partie 3). Enfin, nous ferons état de nos travaux sur les radicaux formés à partir de sels d'aryldiazoniums. Nous montrerons qu'il est possible de réaliser des réactions d'additions radicalaires intramoléculaires, permettant l'accès à des hétérocycles variés (Partie 4).

Synthèse diastéréosélective de diols-1,3 et de triols-1,3,5 à partir de sulfones vinyliques. Delphine Rotulo-Sims Peu d'études spécifiques ont précédemment été consacrées à la construction de diols-1,3 syn fonctionnalisés en α par une double liaison. En revanche, la synthèse de triols-1,3,5 ayant fait l'objet de nombreuses publications ultérieures, il nous est paru intéressant, avant d'exposer nos résultats, de consacrer une première partie aux méthodes existant dans la littérature pour la synthèse diastéréosélective de ces polyols. Nous présenterons ensuite notre stratégie générale pour élaborer ces deux types de structures. Celle-ci fait intervenir un précurseur commun aisément accessible, la vinylsulfone I et est représentée sur le schéma rétrosynthétique ci-contre. Notre approche pour élaborer des triols 1,3,5 repose sur un couplage de type Julia entre la β-hydroxysulfone II – obtenue de manière diastéréosélective à partir de I – et un composé carbonylé. Cette approche sera développée au cours d'une seconde partie. Notre troisième partie sera consacrée à la construction de diols 1,3-syn fonctionnalisés en α par une double liaison. Ceux-ci pourraient être obtenus, après couplage de I sur un composé carbonylé conduisant à un intermédiaire IV, par une séquence addition conjuguée/élimination, suivie d'une réduction de la sulfone vinylique. Une dernière partie sera consacrée à la mise au point d'une nouvelle méthode de déprotection des éthers de triéthylsilyle mise en évidence au cours de nos travaux.

La crise économique François Roulet L'économie par définition est une notion d'équilibre dans un échhange entre un vendeur et un acheteur. Ceci sous entend que l'acheteur ait les moyens d'acheter et le vendeur des produits ou des services à vendre. Sur le plan de la macro économie il existe un important déséquilibre nord-sud, est - ouest. Des déséquilibres existent également en micro économie: si on prend l'éxemple de la Chine son économie se développe presque exclusivement en externe. Les salaires sont très bas, le marché interne se développe peu, l'activité venant de l'exportation des produits qu'elle fabrique pour eux.

Political Connection and Financial Performance: Evidence from Chinese Small-and-Medium Enterprises Sujuan Xie et al. Since 1978, China gradually adopted a series of reform policies aiming to transform its former central planned economy to a socialist market economy. For the past three decades, the economic reform has brought China a flourishing private sector: it has grown at an annual rate of twenty percent, far above the economy's eight percent average growth for the same period (Tsai, 2002). Moreover, the non-state sector in China has accounted for two-thirds of total productivity and GDP (Welborn, 2003). The high-speed development of the private sector has been achieved primarily by decentralization of decision making power from the government to enterprises (McMillan & Woodruff, 2002; Siu & Liu, 2005). This decentralization process led to transformation of those large state-owned enterprises and spur of private small-and-medium enterprise (SMEs), such as the flourishing of township-and-village enterprises (TVEs). While most attention has been paid on how the transformation of large SOEs accelerated the development of private sectors, the creation and development of SMEs has had a significant influence on the development of the private economy, a fact that has been noted recently by sociologists. The rise of those small businesses raises several questions about the way in which China's SMEs has developed. One of these is whether there is a Chinese style of the development of SMEs which differs from that in capitalist economies. According to 3 resource-based theory, in capitalist economies the basis for a firm's competitive advantage lies primarily in its application of the valuable resources that are at the firm's disposal (Rumelt, 1984, p557-558; Wernerfelt, 1995, p172). However, developing in a transitional economy where the market is not the dominant mechanism for the allocation of resources, China's SMEs have developed different strategies to gain better financial performance. This paper, therefore, tries to explain both theoretically and empirically what is the China's style of development of SMEs, particularly focusing on the political connectivity and the financial performance of SMEs. For the rest sections of this paper we firstly deal with the theoretical debate on the development of firms in China's traditional economy.. Secondly, the methodology of this paper will be discussed. A multi-level modelling is used to describe the political connectivity and the financial performance of China's publically listed SMEs. Finally, research results will be presented and further discussed.

Forecasting volatility in the presence of Leverage Effect Rémi Rhodes et al. We define a simple and tractable method for adding the Leverage effect in general volatility predictions. As an application, we compare volatility predictions with and without Leverage on the SP500 Index during the period 2002-2010.

The set of realizations of a max-plus linear sequence is semi-polyhedral Natacha Portier et al. We show that the set of realizations of a given dimension of a max-plus linear sequence is a finite union of polyhedral sets, which can be computed from any realization of the sequence. This yields an (expensive) algorithm to solve the max-plus minimal realization problem. These results are derived from general facts on rational expressions over idempotent commutative semirings: we show more generally that the set of values of the coefficients of a commutative rational expression in one letter that yield a given max-plus linear sequence is a semi-algebraic set in the max-plus sense. In particular, it is a finite union of polyhedral sets.

Semi-Automatic Synthesis of Security Policies by Invariant-Guided Abduction - Full version Clément Hurlin et al. We present a specification approach of secured systems as transition systems and security policies as constraints that guard the transitions. In this context, security properties are expressed as invariants. Then we propose an abduction algorithm to generate possible security policies for a given transition-based system. Because abduction is guided by invariants, the generated security policies enforce security properties specified by these invariants. In this framework we are able to tune abduction in two ways in order to: (i) filter out bad security policies and (ii) generate additional possible security policies. Invariant-guided abduction helps designing policies and thus allows using formal methods much earlier in the process of building secured systems. This approach is illustrated on role-based access control systems.

From speech to emotional interaction: EmotiRob project Marc Le Tallec et al. This article presents research work done in the domain of nonverbal emotional interaction for the EmotiRob project. It is a component of the MAPH project, the objective of which is to give comfort to vulnerable children and/or those undergoing long-term hospitalisation through the help of an emotional robot companion. It is important to note that we are not trying to reproduce human emotion and behavior, but trying to make a robot emotionally expressive. This paper will present the dierent hypotheses we have used from understanding to emotional reaction. We begin the article with a presentation of the MAPH and EmotiRob project. Then, we quickly describe the speech undestanding system, the iGrace computational model of emotions and integration of dynamics behavior. We conclude with a description of the architecture of Emi, as well as improvements to be made to its next generation.

Detecting multiple change-points in general causal time series using penalized quasi-likelihood Jean-Marc Bardet et al. This paper is devoted to the off-line multiple change-point detection in a semiparametric framework. The time series is supposed to belong to a large class of models including AR($\infty$), ARCH($\infty$), TARCH($\infty$),... models where the coefficients change at each instant of breaks. The different unknown parameters (number of changes, change dates and parameters of successive models) are estimated using a penalized contrast built on conditional quasi-likelihood. Under Lipshitzian conditions on the model, the consistency of the estimator is proved when the moment order $r$ of the process satisfies $r\geq 2$. If $r\geq 4$, the same convergence rates for the estimators than in the case of independent random variables are obtained. The particular cases of AR($\infty$), ARCH($\infty$) and TARCH($\infty$) show that our method notably improves the existing results.

Contribution à l'introduction des probabilités au collège : rapports d'élèves à quelques notions probabilistes Mounir Dhieb Ce travail s'intéresse à l'aléatoire et, plus précisément, à l'introduction des probabilités au collège. Il s'inscrit dans le contexte de l'évolution des programmes qui ont officialisé l'approche fréquentiste des probabilités. Nous y avons abordé ce qui existe au niveau des connaissances des élèves, notamment celles disponibles avant toute rencontre scolaire de l'aléatoire (les connaissances spontanées) et ce qui peut exister au niveau de l'introduction des probabilités au collège. Pour étudier le terrain spontané des connaissances, nous avons procédé à une série d'expérimentations de type diagnostic portant sur des objets probabilistes tels que la notion de quantification des probabilités et celle d'indépendance. L'outil d'analyse adopté est la notion de conception, centrale dans notre travail, qui émerge de la théorie des champs conceptuels et que nous avons formalisée en termes empruntés à la Théorie Anthropologique du Didactique. Il en ressort notamment la difficulté de comprendre le tirage avec remise et la rareté de l'apparition de la conception "cas favorables/cas possibles". Le besoin d'un enseignement approprié étant montré, nous avons mis en place une expérimentation didactique où nous ménageons les deux approches "a priori" et "fréquentiste". Dans l'analyse de cette expérimentation, nous avons recouru à l'articulation de la Théorie des Situations Didactiques et de la didactique professionnelle. Cette analyse nous a fourni des informations en termes de tâches prescrites et tâches effectives, de milieux et de contrats didactiques. En conclusion, l'expérimentation précédente représente une esquisse d'une séquence d'enseignement qui reste à confronter à la contingence.

(Very) short proof of Rayleigh's Theorem (and extensions) Olivier Bernardi Consider a walk in the plane made of $n$ steps of length 1, with directions chosen independently and uniformly at random at each step. Rayleigh's Theorem asserts that the probability for such a walk to end at a distance less than 1 from its starting point is $1/(n+1)$. We give an elementary proof of this result. We also prove the following generalization valid for any probability distribution $\mu$ on the positive real numbers: if two walkers start at the same point and make respectively $i$ and $j$ independent steps with uniformly random directions and with lengths chosen according to $\mu$, then the probability that the first walker ends farther than the second is~$i/(i+j)$.

Physical origin of shear-banding in jammed systems Philippe Coussot et al. Jammed systems all have a yield stress. Among these materials some have been shown to shear-band but it is as yet unclear why some materials develop shear-band and some others do not. In order to rationalize existing data concerning the flow characteristics of jammed systems and in particular understand the physical origin of such a difference we propose a simple approach for describing the steady flow behaviour of yield stress fluids, which retains only basic physical ingredients. Within this frame we show that in the liquid regime the behaviour of jammed systems turns from that of a simple yield stress fluid (exhibiting homogeneous flows) to a shear-banding material when the ratio of a characteristic relaxation time of the system to a restructuring time becomes smaller than 1, thus suggesting a possible physical origin of these trends.

Black Holes and Galactic Density Cusps : From Black Hole to Bulge Morgan Le Delliou et al. Aims. In this paper we continue our study of density cusps that may contain central black holes. Methods. We recall our attempts to use distribution functions with a memory of self-similar relaxation, but mostly they apply only in restricted regions of the global system. We are forced to consider related distribution functions that are steady but not self-similar. Results. One remarkably simple distribution function that has a filled loss cone describes a bulge that transits from a near black hole domain to an outer 'zero flux' regime where$\rho\propto r^{-7/4}$. The transition passes from an initial inverse square profile through a region having a 1/r density profile. The structure is likely to be developed at an early stage in the growth of a galaxy. A central black hole is shown to grow exponentially in this background with an e-folding time of a few million years. Conclusions. We derive our results from first principles, using only the angular momentum integral in spherical symmetry. The initial relaxation probably requires bar instabilities and clump-clump interactions.

Black Holes and Galactic Density Cusps Spherically Symmetric Anisotropic Cusps Morgan Le Delliou et al. Aims: In this paper we study density cusps that may contain central black holes. The actual co-eval self-similar growth would not distinguish between the central object and the surroundings. Methods: To study the environment of a growing black hole we seek descriptions of steady `cusps' that may contain a black hole and that retain at least a memory of self-similarity. We refer to the environment in brief as the `bulge' and on smaller scales, the `halo'. Results: We find simple descriptions of the simulations of collisionless matter by comparing predicted densities, velocity dispersions and distribution functions with the simulations. In some cases central point masses may be included by iteration. We emphasize that the co-eval self-similar growth allows an explanation of the black hole bulge mass correlation between approximately similar collisionless systems. Conclusions: We have derived our results from first principles assuming adiabatic self-similarity and either self-similar virialisation or normal steady virialisation. We conclude that distribution functions that retain a memory of self-similar evolution provide an understanding of collisionless systems. The implied energy relaxation of the collisionless matter is due to the time dependence. Phase mixing relaxation may be enhanced by clump-clump interactions.

Black Holes and Galactic Density Cusps : From Black Hole to Bulge Morgan Le Delliou et al. Aims. In this paper we continue our study of density cusps that may contain central black holes. Methods. We recall our attempts to use distribution functions with a memory of self-similar relaxation, but mostly they apply only in restricted regions of the global system. We are forced to consider related distribution functions that are steady but not self-similar. Results. One remarkably simple distribution function that has a filled loss cone describes a bulge that transits from a near black hole domain to an outer 'zero flux' regime where$\rho\propto r^{-7/4}$. The transition passes from an initial inverse square profile through a region having a 1/r density profile. The structure is likely to be developed at an early stage in the growth of a galaxy. A central black hole is shown to grow exponentially in this background with an e-folding time of a few million years. Conclusions. We derive our results from first principles, using only the angular momentum integral in spherical symmetry. The initial relaxation probably requires bar instabilities and clump-clump interactions.

Black Holes and Galactic Density Cusps Spherically Symmetric Anisotropic Cusps Morgan Le Delliou et al. Aims: In this paper we study density cusps that may contain central black holes. The actual co-eval self-similar growth would not distinguish between the central object and the surroundings. Methods: To study the environment of a growing black hole we seek descriptions of steady `cusps' that may contain a black hole and that retain at least a memory of self-similarity. We refer to the environment in brief as the `bulge' and on smaller scales, the `halo'. Results: We find simple descriptions of the simulations of collisionless matter by comparing predicted densities, velocity dispersions and distribution functions with the simulations. In some cases central point masses may be included by iteration. We emphasize that the co-eval self-similar growth allows an explanation of the black hole bulge mass correlation between approximately similar collisionless systems. Conclusions: We have derived our results from first principles assuming adiabatic self-similarity and either self-similar virialisation or normal steady virialisation. We conclude that distribution functions that retain a memory of self-similar evolution provide an understanding of collisionless systems. The implied energy relaxation of the collisionless matter is due to the time dependence. Phase mixing relaxation may be enhanced by clump-clump interactions.

Sur l'identification des paramètres des lois de comportement des roches argileuses. Brice Lecampion Ce travail a pour but de mettre au point des méthodes d'identification des paramètres constitutifs des roches argileuses. Dans le cadre du projet de laboratoire de recherche souterrain de l'ANDRA, il est nécessaire de développer ce type de méthodes en vue de l'interprétation des nombreuses mesures qui seront pratiquées sur site. On s'est focalisé sur deux aspects rhéologiques majeurs du comportement de ce type de roche: le comportement poroélastique d'une part et le comportement élasto-viscoplastique d'autre part. La première partie se focalise sur l'identification des paramètresporoélastiques. Le chapitre 2 rappelle le problème direct et discute un certain nombre de points importants concernant le problème inverse d'identification. Le troisième chapitre est dédié à la formulation des techniques de calcul de gradient pour le cas poroélastique linéaire. La résolution numérique par éléments finis est discutée. Les méthodes de Différentiation directe et de l'état adjoint sont validées sur un exemple numérique bidimensionnel à l'aide du code de calcul par éléments finis Cast3M. Uidentificationdes coefficients poroélastiques des roches argileuses de Meuse Haute-Marne à partir d'essais de laboratoire est discutée en détail dans le chapitre 4. L'utilisation de solutions semi-explicites approchées des problèmes directs permet d'obtenir une méthode d'identification rapide. La deuxième partie du mémoire porte sur l'identification des paramètres élasto-viscoplastiques. Les traits ducomportementviscoplastiques des roches argileuses de Meuse Haute-Marne sont discutés dans le chapitre 5 sur la base des résultats expérimentaux. La modélisation de ce comportement est envisagée. On propose notamment un modèle viscoplastique avececrouissage isotrope non linéaire permettant de reproduire les essais. Les paramètres de cette loi de comportement sont identifiés sur un essai de fluage unîdîmensionnelen conditions drainées. Les déformations différées proviennent alors du comportement poroélastique et viscoplastique de la roche. On montre qu'il est possible de séparer ces deux phénomènes. Tous les paramètres poro-elastoviscoplastiques sont identifiés,une solution semi-explicite de l'essai de fluage est utilisée. Le chapitre 6 présente une méthode d'identification des paramètres élasto-viscoplastiques dans le cas général. Comme déjà présenté au cours du présent chapitre, l'identification se ramène à la minimisation d'une fonctionnelle coût. Le gradient de la fonctionnelle est calculé par Différentiation Directe. La méthode de Différentiation directe est développée dans Cast3M pour la loi élasto-visco-plastique de Norton-Hoff. L'identification des paramètres de cette loi sur des configurations unidimensionelleset bidimensionnelles d'ouvrages souterrains revêtus ou non est ensuite présentée. Les mesures sont simulées par un premier calcul direct puis éventuellement perturbées. L'unicité et la stabilité de ce problèmed'identification sont discutées. La méthode est ensuite appliquée dans le chapitre 7 à un cas réel : le tunnel de la Chamoise. Des modélisations unidimensionnelles et bidimensionnelles en déformation plane sont utilisées pour résoudre le problème direct. Les hypothèses de modélisation sont justifiées. Les paramètres obtenus permettent de reproduire convenablement les données. L'étude de ce cas réel permet également d'émettre un certain nombre de recommandations sur les dispositifs de mesure in situ en vue de l'identification des paramètres des lois de comportement.

Revealing intermittency in experimental data with steep power spectra Eric Falcon et al. The statistics of signal increments are commonly used in order to test for possible intermittent properties in experimental or synthetic data. However, for signals with steep power spectra [i.e., $E(\omega) \sim \omega^{-n}$ with $n \geq 3$], the increments are poorly informative and the classical phenomenological relationship between the scaling exponents of the second-order structure function and of the power spectrum does not hold. We show that in these conditions the relevant quantities to compute are the second or higher degree differences of the signal. Using this statistical framework to analyze a synthetic signal and experimental data of wave turbulence on a fluid surface, we accurately characterize intermittency of these data with steep power spectra. The general application of this methodology to study intermittency of experimental signals with steep power spectra is discussed.

Practical use of variational principles for modeling water waves Didier Clamond et al. This paper describes a method for deriving approximate equations for irrotational water waves. The method is based on a `relaxed' variational principle, i.e., on a Lagrangian involving as many variables as possible. This formulation is particularly suitable for the construction of approximate water wave models, since it allows more freedom while preserving the variational structure. The advantages of this relaxed formulation are illustrated with various examples in shallow and deep waters, as well as arbitrary depths. Using subordinate constraints (e.g., irrotationality or free surface impermeability) in various combinations, several model equations are derived, some being well-known, other being new. The models obtained are studied analytically and exact travelling wave solutions are constructed when possible.

A new integrable system on the sphere and conformally equivariant quantization Christian Duval et al. Taking full advantage of two independent projectively equivalent metrics on the ellipsoid leading to Liouville integrability of the geodesic flow via the well-known Jacobi-Moser system, we disclose a novel integrable system on the sphere $S^n$, namely the ``dual Moser'' system. The latter falls, along with the Jacobi-Moser and Neumann-Uhlenbeck systems, into the category of (locally) Stäckel systems. Moreover, it is proved that quantum integrability of both Neumann-Uhlenbeck and dual Moser systems is insured by means of the conformally equivariant quantization procedure.

Large-Scale Acquisition of Feature-Based Conceptual Representations from Textual Corpora Barry Devereux et al. Methods for estimating people's conceptual knowledge have the potential to be very useful to theoretical research on conceptual semantics. Traditionally, feature-based conceptual representations have been estimated using property norm data; however, computational techniques have the potential to build such representations automatically. The automatic acquisition of feature-based conceptual representations from corpora is a challenging task, given the unconstrained nature of what can constitute a semantic feature. Existing computational methods typically do not target the full range of concept-relation-feature triples occurring in human generated norms (e.g. tiger have stripes) but rather focus on concept-feature tuples (e.g. tiger – stripes) or triples involving specific relations only. We investigate the large-scale extraction of concept-relation-feature triples and the usefulness of encyclopedic, syntactic and semantic information in guiding the extraction process. Our method extracts candidate triples (e.g. tiger have stripes, flute produce sound) from parsed corpus data and ranks them on the basis of semantic information. Our investigation shows the usefulness of external knowledge in guiding feature extraction and highlights issues of methodology and evaluation which need to be addressed in developing models for this task.

Are Drivers' Comparative Risk Judgments about spending Realistic? P. Delhomme et al. We examined how these drivers assess their risk of sanctions and their risk of causing an automobile crash because of speeding in comparison to the estimated risks of other drivers, and how realistic their comparative risk judgments are. We measured the relationship between the drivers' comparative risk judgments, self-reported speeding, and driving-related sensation-seeking. We hypothesized that they would think they have less risk of sanctions and of causing a car accident than others, and their comparative judgments of speeding risks would be linked to self-reported speeding and driving-related sensation-seeking. The study was based on a computerized questionnaire survey conducted with 3,002 young drivers (mean age = 22.3) administered by professional investigators.

Le regard sourd. «Comme un fil tendu entre deux visages...» Yves Delaporte Des sourds il n'est ordinairement retenu que leur déficience auditive. Les conceptions indigènes sont tout autres : les sourds s'auto-définissent comme des visuels. Le regard sourd est un outil collectif qui se construit au contact d'autres sourds. Les langues gestuelles, produites par le corps et reçues par les yeux, en sont la manifestation la plus achevée. Le regard n'est pas utilisé seulement comme récepteur, mais également comme émetteur d'informations d'une extrême finesse. Il intervient dans la grammaticalisation de l'espace, et son importance culturelle se reflète dans le lexique. L'abîme qui sépare ce que sont les sourds des représentations que l'on s'en fait conduit à interpréter ces dernières comme la manifestation d'un audiocentrisme, dernier vestige de l'ethnocentrisme savant.

A new challenge for the energy efficiency evaluation community: energy savings and emissions reductions from urban transportation policies Jean-Sébastien Broc et al. The energy efficiency evaluation community has a large experience about programs for industries, residential and commercial sectors. But now the largest share of the energy consumption growth is due to the transportation sector. Moreover, as the stakes related to the transport sector are considerable, relying on separate actions for technological energy efficiency improvements will not be sufficient. Therefore transport policies now support the development of more integrated approaches. All together, this raises new evaluation issues. This paper first look at what makes or would make the transport specific and different from the other “usual” sectors, as far as the evaluation of energy savings and avoided CO2 emissions is concerned. This is illustrated by a comparison between two simple action types, a car replacement for the transport sector and a boiler replacement for the building sector. Then, taking into account the change toward more integrated action plans, the common evaluation methods used for energy efficiency programs and urban transport planning are discussed, to what extent they can be applied to evaluation of urban mobility plans. Key differences between the building and transport sectors that have an influence on what evaluation methods can be used are: 1) the level of complexity for the definition of the service delivered, 2) the relative importance of variables having long term perspective (building stock) and short term perspective (mobility behaviors). The evaluation of integrated approaches raises additional issues, mainly interactions between the distinct policy measures implemented on a given territory, and causality between the measures implemented and the changes observed. Two interesting tracks stand out: - developing new portfolio approaches starting from available bottom-up methods; - adapting methods used for transport infrastructure design or transport planning. This emphasizes progress that could be achieved by crossing experiences from both scientific communities, evaluation of energy efficiency programs and transport planning.

Multi-model comparison of a major flood in the groundwater-fed basin of the Somme River (France) F. Habets et al. The Somme River Basin is located above a chalk aquifer and the discharge of the somme River is highly influenced by groundwater inflow (90% of river discharge is baseflow). In 2001, the Somme River Basin suffered from a major flood causing damages estimated to 100 million euro (Deneux and Martin, 2001). The purpose of the present research is to evaluate the ability of four hydrologic models to reproduce flood events in the Somme River Basin over an 18-year period, by comparison with observed river discharge and piezometric level as well as satellite-derived extents of flooded area. The models used differ in their computation of surface water budget and in their representation of saturated and unsaturated zones. One model needed structural modification to be able to accurately simulate the riverflows of the Somme river. The models obtained fair to good simulations of the observed piezometric levels, but they all overestimate the piezometric level after flooding, possibly because of a simplistic representation of deep unsaturated flow. Models differ in their annual partition of the infiltration of water within the root zone (mostly driven by simulated evapotranspiration), but these differences are attenuated by water transfers within the saturated and unsaturated zone. As a consequence, the inter-model dispersion of the computed annual baseflow is reduced. The aquifer overflow areas simulated during flooding compare well with local data and satellite images. The models showed that this overflow occurs almost every year in the same areas (in floodplain), and that the flooding of 2001 was characterized by an increase in the quantity of the overflow and not much by a spreading of the overflow areas. Inconsistencies between river discharge and piezometric levels suggest that further investigation are needed to estimate the relative influence of unsaturated and saturated zones on the hydrodynamics of the Somme River Basin.

Compatibility of the French white certificate program to fulfil the objective of energy savings claimed by the Energy Service Directive Dominique Osso et al. The Commission has proposed a Directive on the promotion of end-use efficiency and energy services (ESD) to enhance the cost-effective and efficient end-use of energy in Member States. According to the Directive, the Member States shall adopt and aim to achieve an overall national indicative energy savings target of 9% (or beyond) in 2016. This target is to be reached by way of energy services and other energy efficiency measures. The French National Energy Efficiency Action Plan to comply with the ESD includes a White Certificates scheme (or FWC) as one of the important measures to fulfil the target. As the accountings of energy savings in the FWC scheme and in the ESD are different (e.g. lifetime-cumulated and discounted kWh for FWC and annual kWh for ESD), an analysis of the compliance of both methodologies and a comparison of the assessed savings are necessary. In this paper, we evaluate the compliance with the ESD requirements of two different end-use actions (insulation, heating boiler) included in the FWC scheme. This is done through the concrete case of certificates filed by EDF. The main objective of this evaluation is to assess the contribution of the savings of these FWC actions to the target of the ESD. Finally, general conclusions are drawn about the use of a White Certificates scheme as a monitoring and evaluation tool for the ESD purpose.

Contribution à l'introduction des probabilités au collège : rapports d'élèves à quelques notions probabilistes Mounir Dhieb Ce travail s'intéresse à l'aléatoire et, plus précisément, à l'introduction des probabilités au collège. Il s'inscrit dans le contexte de l'évolution des programmes qui ont officialisé l'approche fréquentiste des probabilités. Nous y avons abordé ce qui existe au niveau des connaissances des élèves, notamment celles disponibles avant toute rencontre scolaire de l'aléatoire (les connaissances spontanées) et ce qui peut exister au niveau de l'introduction des probabilités au collège. Pour étudier le terrain spontané des connaissances, nous avons procédé à une série d'expérimentations de type diagnostic portant sur des objets probabilistes tels que la notion de quantification des probabilités et celle d'indépendance. L'outil d'analyse adopté est la notion de conception, centrale dans notre travail, qui émerge de la théorie des champs conceptuels et que nous avons formalisée en termes empruntés à la Théorie Anthropologique du Didactique. Il en ressort notamment la difficulté de comprendre le tirage avec remise et la rareté de l'apparition de la conception "cas favorables/cas possibles". Le besoin d'un enseignement approprié étant montré, nous avons mis en place une expérimentation didactique où nous ménageons les deux approches "a priori" et "fréquentiste". Dans l'analyse de cette expérimentation, nous avons recouru à l'articulation de la Théorie des Situations Didactiques et de la didactique professionnelle. Cette analyse nous a fourni des informations en termes de tâches prescrites et tâches effectives, de milieux et de contrats didactiques. En conclusion, l'expérimentation précédente représente une esquisse d'une séquence d'enseignement qui reste à confronter à la contingence.

In your face! Ask Katzeff Throughout time the face of power has constituted a favourite target of demon¬strations of dissent and social revolt. The face of the King, the Emperor, the President, the Sultan as objects of scorn and ridicule. This article investigates this particular form of physiognomic humiliation as an activist strategy, as a modifica¬tion of the image of power that attempts to establish a rupture in the prevailing social order and thus open up a new field of political potential.

Risque géotechnique et activité symbolique : les habitants des collines lyonnaises en quête de sens Emmanuel Martinais Situées en plein centre de la ville de Lyon, les collines de Fourvière et de la Croix-Rousse connaissent des problèmes récurrents d'instabilité qui, depuis plusieurs décennies, se sont traduits par de nombreux sinistres et quelques grandes catastrophes. Lié à l'existence d'un vaste réseau de galeries souterraines, et plus largement à la présence non contrôlée de circulations hydrauliques dans le sous-sol des collines, ce danger génère une activité symbolique particulière au sein des populations riveraines. En particulier, le monde des souterrains, qui n'est plus utilisé depuis un siècle environ, s'est progressivement reconstruit dans l'imaginaire des habitants. Les lieux ont été réinventés et de nouvelles fonctions leur ont été attribuées. Univers énigmatique, étrange, mystérieux parfois, inaccessible, invisible et comme « en dehors du réel », les souterrains stimulent les imaginations et favorisent la production, le développement et la diffusion d'histoires et de légendes, dont le contenu peut parfois paraître fantaisiste ou irréaliste. Pour autant, toutes ces productions symboliques ne sont pas dénuées d'intérêt car elles permettent de mettre en ordre une réalité qui n'a pas de cohérence apparente, puis de donner un sens aux dangers auxquels sont régulièrement confrontés les habitants de ces collines.

High-Efficiency Self-Adjusting Switched Capacitor DC-DC Converter with Binary Resolution Alexander Kushnerov Switched-Capacitor Converters (SCC) suffer from a fundamental power loss deficiency which make their use in some applications prohibitive. The power loss is due to the inherent energy dissipation when SCC operate between or outside their output target voltages. This drawback was alleviated in this work by developing two new classes of SCC providing binary and arbitrary resolution of closely spaced target voltages. Special attention is paid to SCC topologies of binary resolution. Namely, SCC systems that can be configured to have a no-load output to input voltage ratio that is equal to any binary fraction for a given number of bits. To this end, we define a new number system and develop rules to translate these numbers into SCC hardware that follows the algebraic behavior. According to this approach, the flying capacitors are automatically kept charged to binary weighted voltages and consequently the resolution of the target voltages follows a binary number representation and can be made higher by increasing the number of capacitors (bits). The ability to increase the number of target voltages reduces the spacing between them and, consequently, increases the efficiency when the input varies over a large voltage range. The thesis presents the underlining theory of the binary SCC and its extension to the general radix case. Although the major application is in step-down SCC, a simple method to utilize these SCC for step-up conversion is also described, as well as a method to reduce the output voltage ripple. In addition, the generic and unified model is strictly applied to derive the SCC equivalent resistor, which is a measure of the power loss. The theoretical predictions are verified by simulation and experimental results.

A new challenge for the energy efficiency evaluation community: energy savings and emissions reductions from urban transportation policies Jean-Sébastien Broc et al. The energy efficiency evaluation community has a large experience about programs for industries, residential and commercial sectors. But now the largest share of the energy consumption growth is due to the transportation sector. Moreover, as the stakes related to the transport sector are considerable, relying on separate actions for technological energy efficiency improvements will not be sufficient. Therefore transport policies now support the development of more integrated approaches. All together, this raises new evaluation issues. This paper first look at what makes or would make the transport specific and different from the other “usual” sectors, as far as the evaluation of energy savings and avoided CO2 emissions is concerned. This is illustrated by a comparison between two simple action types, a car replacement for the transport sector and a boiler replacement for the building sector. Then, taking into account the change toward more integrated action plans, the common evaluation methods used for energy efficiency programs and urban transport planning are discussed, to what extent they can be applied to evaluation of urban mobility plans. Key differences between the building and transport sectors that have an influence on what evaluation methods can be used are: 1) the level of complexity for the definition of the service delivered, 2) the relative importance of variables having long term perspective (building stock) and short term perspective (mobility behaviors). The evaluation of integrated approaches raises additional issues, mainly interactions between the distinct policy measures implemented on a given territory, and causality between the measures implemented and the changes observed. Two interesting tracks stand out: - developing new portfolio approaches starting from available bottom-up methods; - adapting methods used for transport infrastructure design or transport planning. This emphasizes progress that could be achieved by crossing experiences from both scientific communities, evaluation of energy efficiency programs and transport planning.

Compatibility of the French white certificate program to fulfil the objective of energy savings claimed by the Energy Service Directive Dominique Osso et al. The Commission has proposed a Directive on the promotion of end-use efficiency and energy services (ESD) to enhance the cost-effective and efficient end-use of energy in Member States. According to the Directive, the Member States shall adopt and aim to achieve an overall national indicative energy savings target of 9% (or beyond) in 2016. This target is to be reached by way of energy services and other energy efficiency measures. The French National Energy Efficiency Action Plan to comply with the ESD includes a White Certificates scheme (or FWC) as one of the important measures to fulfil the target. As the accountings of energy savings in the FWC scheme and in the ESD are different (e.g. lifetime-cumulated and discounted kWh for FWC and annual kWh for ESD), an analysis of the compliance of both methodologies and a comparison of the assessed savings are necessary. In this paper, we evaluate the compliance with the ESD requirements of two different end-use actions (insulation, heating boiler) included in the FWC scheme. This is done through the concrete case of certificates filed by EDF. The main objective of this evaluation is to assess the contribution of the savings of these FWC actions to the target of the ESD. Finally, general conclusions are drawn about the use of a White Certificates scheme as a monitoring and evaluation tool for the ESD purpose.

APPROCHES DE THÉRAPIES GÉNIQUES POUR DES MALADIES NEUROMUSCULAIRES Gilles Moulay La thérapie génique de myopathies telles que la dystrophie musculaire de Duchenne nécessite une approche systémique afin de traiter l'ensemble de la musculature. Le vecteur AAV est actuellement le plus efficace pour transduire le muscle. Nous montrons que la biodistribution du vecteur AAV administré par voie veineuse peut être modifiée en utilisant diverses stratégies adjuvantes chez la souris saine. La pré-injection de polymères permet ainsi d'améliorer la transduction des muscles par le vecteur AAV, ou encore de baisser la réponse immune neutralisante induite par l'injection intraveineuse du vecteur. Nous abordons également l'impact de facteurs modulateurs exogènes ou endogènes – tels que la procédure d'administration ou certains facteurs sanguins – sur la transduction systémique de l'AAV. Dans une seconde approche, nous avons évalué le transfert de gènes dans le muscle dystrophique afin de sécréter dans la circulation sanguine une protéine transgénique fusionnant le récepteur soluble I du TNF-α avec le fragment constant d'une immunoglobuline (TNFR-Is/mIgG1). La comparaison des cinétiques de sécrétion obtenu après le transfert de gène dans le muscle de souris saines ou de souris dystrophiques mdx indique que le contexte inflammatoire du muscle dystrophique favorise une réponse immune contre le transgène. Nous montrons que l'expression et la sécrétion d'un variant murin peu immunogène du TNFR-Is/mIgG1 améliore la fonction musculaire de la souris mdx sans toutefois conférer un avantage sélectif aux fibres musculaires dystrophiques qui continuent leur cycle de nécrose et de régénération.

Gelation studies of a cellulose-based biohydrogel: the influence of pH, temperature and sterilization. Ahmed Fatimi et al. The present paper investigates the rheological properties of silated hydroxypropylmethylcellulose (Si-HPMC) biohydrogel used for biomaterials and tissue engineering applications. The general property of this modified cellulose ether is the occurrence of self-hardening due to silanol condensation subsequent to a decrease in pH (from 12.4 to nearly 7.4). The behavior of unsterilized and sterilized Si-HPMC solutions in diluted and concentrated domains is first described and compared. In addition, the influence of physiological parameters such as pH and temperature on the rate of the gelation process is studied. In dilute solution, the intrinsic viscosity ([eta]) of different pre-steam sterilization Si-HPMC solutions indicates that macromolecular chains occupy a larger hydrodynamic volume than the post-steam sterilization Si-HPMC solutions. Although the unsterilized Si-HPMC solutions demonstrate no detectable influence of pH upon the rheological behavior, a decrease in the limiting viscosities (eta(0)) of solutions with increasing pH is observed following steam sterilization. This effect can be explained by the formation of intra- and intermolecular associations during the sterilization stage originating from the temperature-induced phase separation. The formation of Si-HPMC hydrogels from injectable aqueous solution is studied after neutralization by different acid buffers leading to various final pHs. Gelation time (t(gel)) decreases when pH increases (t(gel) varies from 872 to 11s at pH 7.4 and 11.8, respectively). The same effect is observed by increasing the temperature from 20 to 45 degrees C. This is a consequence of the synergistic effect of the increased reaction rate and acid buffer diffusion. pH and temperature are important parameters in the gelation process and their influence is a key factor in controlling gelation time. By adapting the gel parameters one could propose hydrogels with cross-linking properties adapted to clinical applications by controlling the amount of pH of neutralization and temperature.

Morphogenèse du crâne des Primates: analyse factorielle, implications taxinomiques, place et redéfinition du genre Homo Nicole Petit-Maire et al. Une analyse factorielle de crânes de Primates décrit la variation totale de l'ordre à partir de la croissance post-natale et la position de quelques spécimens fossiles par rapport à la morphologie crânienne d'espèces actuelles.

Detecting multiple change-points in general causal time series using penalized quasi-likelihood Jean-Marc Bardet et al. This paper is devoted to the off-line multiple change-point detection in a semiparametric framework. The time series is supposed to belong to a large class of models including AR($\infty$), ARCH($\infty$), TARCH($\infty$),... models where the coefficients change at each instant of breaks. The different unknown parameters (number of changes, change dates and parameters of successive models) are estimated using a penalized contrast built on conditional quasi-likelihood. Under Lipshitzian conditions on the model, the consistency of the estimator is proved when the moment order $r$ of the process satisfies $r\geq 2$. If $r\geq 4$, the same convergence rates for the estimators than in the case of independent random variables are obtained. The particular cases of AR($\infty$), ARCH($\infty$) and TARCH($\infty$) show that our method notably improves the existing results.

Adaptive Monte Carlo on multivariate binary sampling spaces Christian Schäfer et al. A Monte Carlo algorithm is said to be adaptive if it can adjust automatically its current proposal distribution, using past simulations. The choice of the parametric family that defines the set of proposal distributions is critical for a good performance. We treat the problem of constructing such parametric families for adaptive sampling on multivariate binary spaces. A practical motivation for this problem is variable selection in a linear regression context, where we need to either find the best model, with respect to some criterion, or to sample from a Bayesian posterior distribution on the model space. In terms of adaptive algorithms, we focus on the Cross-Entropy (CE) method for optimisation, and the Sequential Monte Carlo (SMC) methods for sampling. Raw versions of both SMC and CE algorithms are easily implemented using binary vectors with independent components. However, for high-dimensional model choice problems, these straightforward proposals do not yields satisfactory results. The key to advanced adaptive algorithms are binary parametric families which take at least the linear dependencies between components into account. We review suitable multivariate binary models and make them work in the context of SMC and CE. Extensive computational studies on real life data with a hundred covariates seem to prove the necessity of more advanced binary families, to make adaptive Monte Carlo procedures efficient. Besides, our numerical results encourage the use of SMC and CE methods as alternatives to techniques based on Markov chain exploration.

Nonparametric estimation of the derivatives of the stationary density for stationary processes Emeline Schmisser Abstract In this article, our aim is to estimate the successive derivatives of the stationary density $f$ of a strictly stationary and $ \beta$-mixing process$ \left(X_{t}\right)_{t\geq0}$. This process is observed at discrete times $t=0,\Delta,\ldots,n\Delta$. The sampling interval $\Delta$ can be fixed or small. We use a penalized least-square approach to compute adaptive estimators. If the derivative $f^{(j)}$ belongs to the Besov space $\mathcal{B}_{2,\infty}^{\alpha}$, then our estimator converges at rate $\left(n\Delta\right)^{-\alpha/(2\alpha+2j+1)}$. Then we consider a diffusion with known diffusion coefficient. We use the particular form of the stationary density to compute an adaptive estimator of its first derivative $f'$. When the sampling interval $\Delta$ tends to 0, and when the diffusion coefficient is known, the convergence rate of our estimator is $\left(n\Delta\right)^{-\alpha/(2\alpha+1)}$. When the diffusion coefficient is known, we also construct a quotient estimator of the drift for low-frequency data.