Les composés azotés ont un grand intérêt car cet élément se retrouve dans la plupart des produits naturels et pharmaceutiques, de sorte que le développement de méthodes efficaces pour leur préparation est hautement souhaitable. Tout d'abord, une méthode stéréodivergente et énantiosélective a été développée pour la synthèse totale des alcaloïdes de type chaetominine, y compris les structures proposées de la (-)-pseudofischerine, de l’(-)-aniquinazoline D et de l’(-)-isochaetominine, de l’(-)-isochaetominines A-C, de la (+)-14-epi-isochaetominine C, ainsi que les quatre stéréoisomères jusqu'ici inconnus de l'isochaetominine C. A la lumière de nos travaux de synthèse, les structures de la (-)-pseudofischerine naturelle et l’(-)-aniquinazoline D ont été révisées comme l’(-)-isochaetominine C, et la structure de l’(-)-isochaetominine naturelle a été révisée comme la (-)-11-epi-chaetominine. Ensuite, une réaction de cyclisation en cascade de radicaux azaphiles a été développée conduisant à une synthèse efficace d'hétéroaromatiques de type imidazo-accolés à partir de carbamates N-hétéroaryl-O-propargyliques facilement disponibles. La synthèse électrochimique organocatalysée est généralisable, tolère de nombreux groupes fonctionnels, et se déroule dans des conditions douces sans besoin de catalyse par les métaux de transition, ni d'oxydants. Enfin, deux approches à des analogues de l'unité CHOI ont été développées. Les étapes clés de la de synthèse sont basées sur la C-allylation et la N-allylation palladocatalysées, qui permettent la transformation d’un substrat bis-allylique cyclique en un hexahydroindole. En fonction de la stratégie appliquée, la position de la fonction alcène de l'hexahydroindole peut se retrouver sur des positions différentes du squelette. L’homologation d’un atome de carbone suivie d'une époxydation ou d'une syn-dihydroxylation des intermédiaires bicycliques résultants fournissent les analogues CHOI désirés. / Nitrogen-containing compounds have a great interest as this element is found in natural products and drugs, thus the development of efficient methods for their preparation is highly desirable. First, a stereodivergent and enantioselective method has been developed for the total syntheses of chaetominine-type alkaloids including the proposed structures of (-)-pseudofischerine, (-)-aniquinazoline D and (-)-isochaetominine, (-)-isochaetominines A–C, (+)-14-epi-isochaetominine C, as well as the four hitherto unknown stereoisomers of isochaetominine C. The structures of natural (-)-pseudofischerine and (-)-aniquinazoline D have been revised as (-)-isochaetominine C and the structure of the natural (-)-isochaetominine have been revised to (-)-11-epi-chaetominine based on our synthetic efforts. Next, an azaphilic radical cascade cyclization reaction has been developed leading to the efficient synthesis of imidazo-fused heteroaromatics from easily available N-heteroaryl-O-propargyl carbamates. The organocatalyzed electrochemical synthesis has a broad scope, tolerates many common functional groups, and proceeds under mild conditions without the need of transition-metal catalysis or chemical oxidant. Finally, two approaches toward analogs of the CHOI unit have been developed. The key steps of the synthetic route were based on Pd-catalyzed C-allylation and N-allylation, which converted a cyclic bis-allylic substrate into a hexahydroindole scaffold. Depending on the strategy applied, the position of alkene moiety of the resulting hexahydroindole can be obtained at different positions. One-carbon homologation followed by epoxidation or syn-dihydroxylation of the resulting bicyclic intermediates afforded the desired CHOI analogues.

Le travail présenté dans ce manuscrit concerne le développement d'une nouvelle voie d'accès à une famille de butyrolactames naturels à fort potentiel thérapeutique basé sur une réaction de cycloaddition [2+2] suivie d'une expansion de cycle. Dans la partie principale, une méthodologie permettant l'accès aux cyclobutanones hautement fonctionnalisées par cycloaddition [2+2] entre des éthers d'énols chiraux et divers cétènes fonctionnalisés a été développée. Avec cette méthodologie, diverses cyclobutanones ont pu être obtenues de façon hautement chimio-, régio- et stéréosélective. L'expansion de cycle sur les cyclobutanones préparées précédemment afin d'obtenir le squelette butyrolactame de la (–)-Salinosporamide A a ensuite été étudiée. La dernière partie de ce travail consiste en une étude de la réaction de cycloaddition [2+2] entre un cétène et un éther d'énol activée par un acide de Lewis présent en quantité catalytique. Cette première étude semble indiquer qu'une activation avec un acide de Lewis est possible lorsqu'un éther d'énol encombré est utilisé. / The work reported in this manuscript concerns the development of a new approach to a family of natural butyrolactames, with a high therapeutic potential, based on a [2+2] cycloaddition reaction followed by a ring expansion. In the main part, a procedure for the preparation of highly functionalized cyclobutanones by [2+2] cycloaddition between chiral enols ethers and functionalized ketenes has been developed. With this method, a variety of cyclobutanones were obtained in a highly chemo-, regio- and stéréosélective manner. The ring expansion of the previously prepared cyclobutanones to obtain the butyrolactame skeleton of (–)-Salinosporamide A was next investigated. The last part of this manuscript consists in a study of the [2+2] cycloaddition reaction between ketene and enol ether activated by a Lewis acid in catalytic amount. This first study seems to point out that an activation of [2+2] cycloaddition reaction is possible when a sterically hindered enol ether is used.

Les milieux complexes sont une source d'incertitude importante notamment lorsqu'il s'agit de développer des modèles climatique ou météorologique. Le développement de la couche limite atmosphérique à l'intérieur d'une vallée encaissée, incluant des vents de vallée et de pente, n'est, par exemple, pas résolu, ce qui a un impact considérable sur la prévision de la convection, du transport de polluants, etc... La simulation des grandes échelles de la turbulence (SGE) est un outil qui a montré sa capacité à reproduire finement les structures turbulentes dans ce type de contextes au travers des approches idéalisées. L'extension de la SGE aux milieux naturels est réalisée dans cette thèse qui s'articule en trois parties. La première partie présente les équations et les notions nécessaires à la compréhension des problèmes de turbulence dans la couche limite atmosphérique. On s'attache à décrire le cadre des lois issues de la théorie des similitudes et le cadre de la turbulence optique. La seconde partie présente des résultats issus de deux simulations idéales dans lesquelles nous comparons les résultats issus de la simulation avec d'une part les lois issues de la théorie des similitudes et d'autre part les données radar disponible lors de la campagne IHOP. L'utilisation d'un maillage raffinée près du sol permet d'améliorer les profils verticaux des champs turbulents en améliorant la prédiction des gradients à l'interface sol/atmosphère. De plus, le profil de couche limite est bien reproduit par les profils du paramètre de structure des fluctuations de l'indice de réfraction de l'air simulé si on compare avec les résultats issus du radar. Globalement, la dynamique des champs turbulents résolus par le modèle reproduise une dynamique et des ordres de grandeurs corrects conformes à nos attentes. Une fois l'évaluation du modèle effectuée, une simulation a été mise en place autour de la campagne d'observation VOTALP située dans le sud de la Suisse. Cette simulation comprend 5 domaines emboités allant de 16 kms de résolution horizontales pour le plus grand domaine à 100m pour le plus petit domaine. L'important dispositif déployé durant la campagne VOTALP située dans une vallée dans le sud de la Suisse a permis de confronter les résultats issus de la modélisation à haute résolution avec ces données d'observation. Les résultats obtenus ont, entre autre, montré que la simulation à haute résolution est un outil adapté pour l'étude des phénomènes de basses couches et notamment la turbulence optique en milieu complexe. / Complex environments are an important source of uncertainty especially when it comes to developing climate models and weather. The development of the atmospheric boundary layer within a valley, including valley and slope winds is, for example, unresolved, which has a significant impact on the prediction of convection, of transport of pollutants, etc ... The large eddy simulation of turbulence (LES) is a tool that has demonstrated its ability to reproduce turbulent structures in such idealized contexts. The extension of the LES to natural environments is performed in this thesis divided into three parts. The first part presents the equations and the concepts necessary to understanding the problems of turbulence in the atmospheric boundary layer. It attempts to describe the laws for the similarity theories and the context of optical turbulence. The second part presents the results of two ideals simulations and we compare the results of the simulation with one hand the laws of the similarity theories and in other hand with radar data available in the IHOP campaign. The use of a refined mesh near the floor improves vertical profiles of turbulent fields improving prediction gradients at the interface soil / atmosphere. In addition, the boundary layer profile seems to be well reproduced by Cn2 profiles when compared with the results from the radar. Overall, the dynamics of turbulent fields solved are in good agreement with our expectations. Once the model evaluation performed, a simulation was set up around the measurement campaign VOTALP located in the south of Switzerland. This simulation includes five nested domains ranging from 16 km horizontal resolution for the largest to 100m for the smallest area. The important device deployed during the campaign VOTALP located in a valley in southern Switzerland has to confront the results of modeling the high-resolution observational data. The results obtained, among others, showed that the high-resolution simulation is a suitable tool for the study of the phenomena of lower layers including optical turbulence in complex environments.

La compréhension et la prévision des phénomènes d'éboulements rocheux sont des éléments déterminants pour la gestion des risques dans l'aménagement des zones et des infrastructures de montagnes, qui nécessitent, entre autre, la mise au point d'outils numériques opérationnels permettant d'anticiper la trajectoire des épisodes rocheux et les zones susceptibles d'être impactées. L'approche numérique proposée dans le cadre de la thèse, est basée sur une modélisation numérique discrète qui permet de simuler le comportement collectif de blocs rocheux lors d'un éboulement, en considérant des blocs de géométrie réaliste et une topographie tridimensionnelle du versant de propagation. Pour faciliter son utilisation en bureau d'études, le modèle numérique de contact, qui gère les interaction entre les blocs et entre les blocs et le versant de propagation, fait appel à un nombre restreint de paramètres, pouvant être estimés par des mesures in situ ou par des rétro-analyses de cas existants. Les paramètres les plus influant sur les mécanismes de propagation sont : la géométrie des blocs et la topographie de surface, les paramètres dissipatifs de contact tels que le coefficient de restitution normale qui agit dans la direction normale au contact, le coefficient de frottement qui agit dans la direction tangentielle au plan de contact, et la résistance au roulement entre la pente et les blocs rocheux dans l'hypothèse d'un impact rocheux sur un sol meuble.La thèse présente des nombreuses données de terrain qui ont servies de base à l'analyse des mécanismes de propagation sur d'anciens cas d'éboulements et sur des falaises potentiellement instables. Des méthodes permettant la reconstruction d'un volume instable pour la modélisation de la propagation ont été développées sur la base des modèles tridimensionnels de terrain. Après des tests de validation et de compréhension du modèle numérique, ce dernier a été appliqué à des cas réels. Trois sites, très différents en termes de géométrie, ont été retenus pour tester le modèle numérique. Les paramètres d'études sont suivant les cas, les mécanismes de propagation, les mécanismes de dissipation d'énergie, les zones de dépôt, les forces d'interactions et les énergies d'impact sur des structures de protection.Ce travail a permis d'établir une méthodologie de modélisation des éboulements rocheux adaptée à l'ingénierie. Un protocole spécifique permettant de déterminer ou d'estimer les paramètres a été proposé et des logiciels de pré et post traitements permettant à la fois une analyse pertinente et rapide des résultats ont été développés. La corrélation entre les résultats numériques et les observations de terrain sont satisfaisantes et les résultats en termes de prévision encourageants. / Understanding and predicting rock avalanches are key elements in risk management when developing mountainous areas. Due to the complexity of the mechanisms involved, developments of numerical and operational tools are useful and necessary to properly estimate block trajectories and define riskiest areas. The numerical approach proposed in this thesis is based in the discrete element method which allows simulating the collective behavior of a group of rocks by using realistic block geometries and three-dimensional slope topographies. The numerical contact model handles interaction between the blocks and between the blocks and the slope by using a limited number of parameters that can be estimated by in situ measurements or feed-back analysis of ancient rockfalls events. The most influential parameters in the propagation phenomena are: the geometry and shape of blocks and topography, the contact parameters such as the normal restitution coefficient which acts in the normal direction to the contact, the friction coefficient acting in the tangential direction to the contact plane and the rolling resistance coefficient of blocks with the slope that somehow accounts of the impact mechanisms in case of soft soil.Various field results of past rockfall events or instable rocky cliffs are presented in the thesis. In addition, different procedures allowing the modeling of the whole unstable volume involved in the propagation motion are presented through real applications by using three-dimensional terrain models as input data. The numerical model was applied to three real rockfalls events, very different in terms of geometry. The parameters analyzed concerned mainly the propagation distances and energy dissipation mechanisms, deposit zones, interaction forces and impact energies on protective structures.A specific protocol for determining and estimating the contact parameters was proposed and some pre and post processing software enabling both relevant and rapid analysis of the results have been developed. The correlation between the numerical results and field observations are satisfactory with very encouraging results in terms of forecasting.

Les substances naturelles ont toujours joué un rôle important dans la recherche de nouvelles molécules d’intérêt thérapeutique. Ces produits peuvent être aussi utilisés comme sondes dans l’étude de systèmes biologiques et améliorer notre compréhension de ces phénomènes. Toutefois, la grande majorité des librairies de molécules synthétisées en chimie médicinale dans l’industrie pharmaceutique ou dans la recherche académique sont composées de molécules possédant des squelettes hétérocycliques qui couvrent une faible partie de l’espace des molécules pouvant être potentiellement découvertes (estimation de 1060 molécules organiques sous les 500 Da). Dans ce mémoire, nous décrivons la synthèse de nouvelles librairies de molécules basées sur des squelettes de produits naturels. Ces entités possèdent un niveau de complexité et de diversité élevé. Différentes stratégies ont été développées durant cette thèse dans le but de synthétiser avec efficacité des librairies possédant ces caractéristiques: synthèse divergente de nouveaux squelettes polycycliques catalysée par des métaux de transition, synthèse de dérivés de produits naturels décorés de façon à moduler leur activité biologique et synthèse de librairies encodées avec des acides peptido-nucléiques. / Natural products have played a key role in the search for new drugs. These bioactive molecules can also be used as probes in biological studies and expand our knowledge of the mechanisms involved. Nevertheless, the large majority of chemical libraries currently synthesized in pharmaceutical companies or in academic research centers consist of heterocyclic scaffolds which cover a small part of the available chemical space (1060 molecules below 500 Da). In this dissertation, we describe the synthesis of new libraries based on natural product scaffolds. They present a high level of complexity and diversity. Creative strategies used to quickly generate these libraries have been developed during this PhD such as the divergent synthesis of new polycyclic scaffolds catalyzed by transition metals, the synthesis of terpene derivatives functionalized in order to modulate their biological activity, and the PNA encoded synthesis of small molecules libraries.

Les interactions qu’un métal f entretient avec son environnement sont étudiées dans de nombreux domaines (industrie nucléaire, électronique, …). Pourtant, ces phénomènes sont souvent mal compris d’un point de vue fondamental. Les interactions qui peuvent s’établir entre métaux d et métaux f ont déjà été en partie étudiées, principalement dans le domaine du magnétisme. Les phénomènes de transfert de charge ont cependant été beaucoup moins analysés, malgré une importance croissante dans de nombreux systèmes. Cette étude se propose de développer des systèmes moléculaires permettant d’étudier un certain nombre de propriétés physico-chimiques de systèmes d-4f et d-5f, ainsi que leur transposabilité vers des systèmes polymères de coordination présentant des nœuds métalliques mixtes d et f.Sur les systèmes moléculaires, les études se sont centrées sur le transfert de charge photo-induit d’un métal d vers un métal f et sur leurs propriétés électrochimiques. Pour cela il a été nécessaire de développer plusieurs systèmes de référence moléculaires à base de Ru permettant l’addition d’un métal 4f ou 5f. Les systèmes moléculaires, Ru et mixte Ru-élément f, ont été caractérisés. Des études photo-physiques et électrochimiques comparatives, expérimentales et théoriques (DFT et TD-DFT), entre les systèmes Ru simples, Ru-4f et Ru-5f, ont été menées.Les systèmes de type polymère de coordination ont été abordés afin d’étendre l’étude comparative des systèmes mixtes d-f à des composés 3D. À cette fin, la synthèse de systèmes constitués d’un métal d, d’un élément 4f et d’un ligand ditopique (2,5-dihydroxy-1,4-benzoquinone, DHBQ) a été étudiée, l’objectif étant d’intégrer de façon contrôlée un métal d au sein d’une structure polymère 4f-DHBQ déjà bien connue. Ces études ont montré que l’introduction d’un métal d dans ce type de polymère de coordination n’est pas possible dans les conditions d’études pour des raisons cinétiques. Cependant, pour ces mêmes raisons cinétiques, la présence du métal d lors de la synthèse influe de façon notable sur la morphologie des composés 4f-DHBQ ouvrant d’autres perspectives à ces systèmes 4f. Ainsi il est possible de les utiliser comme précurseurs de matériaux durs (oxydes, carbures) dont les aspects structuraux et microstructuraux sont contrôlé via les propriétés structurales et morphologiques du polymère de coordination. / The interactions between an f metal and its environment are studied in several fields (nuclear industry, electronics …). However, those phenomena are often misunderstood in a fundamental point of view. The interactions which are able to settle between d and f metals are partly studied, mainly in the field of magnetism. The charge transfer phenomena were however less studied, despite an increasing interest in numerous systems. This study intends to develop molecular systems which allow studying numerous physicochemical properties of d-4f and d-5f systems, along with their transposability towards coordination polymers systems exhibiting d and f mixed metallic nodes.On the molecular systems, studies focused on photo-induced charge transfer from a d metal to an f metal and on their electrochemical properties. In order to do this, it was necessary to develop several molecular reference systems based on Ru allowing the addition of a 4f or 5f metal. The molecular systems, Ru and mixed Ru-f element, were characterized. Comparative photo-physical and electrochemical studies, experimental and theoretical (DFT and TD-DFT), between the monometallic Ru and the Ru-4f and Ru-5f systems have been achieved.Coordination polymers systems have been broached to enlarge the comparative study of the d-f mixed systems to 3D compounds. To that end, the synthesis of systems containing a d metal, an f metal and a ditopic ligand (2,5-dihydroxy-1,4-benzoquinone, DHBQ) has been studied, the aim being the controlled integration of the d metal in a well-known 4f-DHBQ polymeric structure. These studies showed that the introduction of a d metal in this type of coordination polymers is not possible in the study conditions for kinetic reasons. However, for the same kinetic reasons, the presence of the d metal during the synthesis influences in a significant way the morphology of the 4f-DHBQ compounds, opening other perspectives to these 4f systems. Thus, it is possible to use them as hard materials precursors (oxides, carbides) whose structural and microstructural aspects are controlled via structural and morphological properties of the coordination polymer.

Discovering relevant knowledge out of unstructured text in not a trivial task. Search engines relying on full-text indexing of content reach their limits when confronted to poor quality, ambiguity, or multiple languages. Some of these shortcomings can be addressed by information extraction and related natural language processing techniques, but it still falls short of adequate knowledge representation. In this thesis, we defend a generic approach striving to be as language-independent, domain-independent, and content-independent as possible. To reach this goal, we offer to disambiguate terms with their corresponding identifiers in Linked Data knowledge bases, paving the way for full-scale semantic enrichment of textual content. The added value of our approach is illustrated with a comprehensive case study based on a trilingual historical archive, addressing constraints of data quality, multilingualism, and language evolution. A proof-of-concept implementation is also proposed in the form of a Multilingual Entity/Resource Combiner & Knowledge eXtractor (MERCKX), demonstrating to a certain extent the general applicability of our methodology to any language, domain, and type of content. / Découvrir de nouveaux savoirs dans du texte non-structuré n'est pas une tâche aisée. Les moteurs de recherche basés sur l'indexation complète des contenus montrent leur limites quand ils se voient confrontés à des textes de mauvaise qualité, ambigus et/ou multilingues. L'extraction d'information et d'autres techniques issues du traitement automatique des langues permettent de répondre partiellement à cette problématique, mais sans pour autant atteindre l'idéal d'une représentation adéquate de la connaissance. Dans cette thèse, nous défendons une approche générique qui se veut la plus indépendante possible des langues, domaines et types de contenus traités. Pour ce faire, nous proposons de désambiguïser les termes à l'aide d'identifiants issus de bases de connaissances du Web des données, facilitant ainsi l'enrichissement sémantique des contenus. La valeur ajoutée de cette approche est illustrée par une étude de cas basée sur une archive historique trilingue, en mettant un accent particulier sur les contraintes de qualité, de multilinguisme et d'évolution dans le temps. Un prototype d'outil est également développé sous le nom de Multilingual Entity/Resource Combiner & Knowledge eXtractor (MERCKX), démontrant ainsi le caractère généralisable de notre approche, dans un certaine mesure, à n'importe quelle langue, domaine ou type de contenu. / Doctorat en Information et communication / info:eu-repo/semantics/nonPublished

The goal I have pursued in writing this dissertation has been to provide the most complete account that I could manage of the various aspects of language that can be labelled metalinguistic, both in the language-system and in discourse. On a rough characterisation, metalanguage is language about language. Since I understand language both as a ‘potential’ (the language-system) and as its actualisation (language as discourse), there are theoretically four situations that can be subsumed under the term ‘metalanguage’: 1. there are lexical items (units in the system) that denote aspects of the system (preposition, noun, conjugation, plural, etc.); 2. there are items that denote elements of discourse (words and phrases like the aforementioned, the latter, etc.). At the same time, there are 3. utterances about the system (e.g. ‘Boston’ is a noun), and 4. utterances about discourse (i.e. about other utterances or parts of utterances, e.g. The old cow said teddible instead of terrible). In both 3 and 4, we have words that reflexively mention linguistic sequences. Following Rey-Debove, I have chosen to call these ‘autonyms’.Note also that discourse about language can be combined with discourse about extralinguistic reality. An utterance about a situation in the world can secondarily say something, for example, about language use; such is the case in The U.S. advocates ‘military action’, as newspapermen call it now, where a comment about a euphemism is appended to a statement about ‘the world’.All in all, this amounts to a fairly large body of data that is varied in kind. My goal has been to bring some order to this variegated set, to highlight in what respects its elements are similar and dissimilar. Thus, I have sought to sort out a number of issues that had not, as far as I could judge, been treated satisfactorily on previous occasions, and to make my descriptions compatible with the theory that was gradually taking shape. In particular, I have underlined the strong connections between the system-level aspects of metalanguage and its discourse manifestations, and I have been led to suggest that the latter ‘leak into’ the system. Besides, I have tried to give a more thorough account of certain properties of metalinguistic discourse, notably the recursiveness of mention or quotation, and its referential diversity. When I felt that I had come to an adequate account of metalinguistic discourse, I have attempted to supply a typology of its various manifestations that would integrate most of the criteria brought up in previous attempts. In the final part of the dissertation, I have brought together what I regard as a series of genuine challenges to the best existing theories of metalinguistic discourse, and have attempted to frame what possible solutions could be.THINGS IN SENTENCES, INFINITE LEXICON? P-ÊÊ UNE CODA APRÈS RECA + CHAPTER 8***The very notion of metalanguage originated in formal logic in the first half of the 20th c. Soon, some of the concepts developed by logicians were taken over by philosophers of language (and subsequently by a few linguists). That was notably the case with the distinction between the use and the mention of a linguistic sequence; use designating the ordinary, transparent, employment of an expression to denote something outside language and mention its being chosen as a topic for discussion. When the subject came under the scrutiny of philosophers of language, the essentially prescriptive approach of the logician (the logician decreed which features his languages and metalanguages should possess), was turned into an attempt at describing actual linguistic mechanisms. It is in this tradition that I situate myself.Philosophers of language have turned out to be particularly interested in quotation (the mention of linguistic expressions), but I have thought it useful to introduce a term that covered not just quotation, but also mention-without-quote-marks, as well as hybrid cases like example 5. This term is reflexive metalinguistic demonstration, but for convenience’ sake I shall make do with metalinguistic demonstration.In Chapter 2, I have examined in detail the main theories of metalinguistic demonstration put forward in the course of the 20th c. namely the Name, Description, Demonstrative and Identity theories. In the process, I have been able to gradually identify the various properties of metalinguistic demonstrations that should be regarded as essential. And I have also formed a clearer idea of the body of data that a theory should be able to account for. In the end, I have been able to outline what I believe is a sound theory of metalinguistic demonstrations. This theory is chiefly informed by the proposals of François Recanati (2000, 2001), supplemented with insights of Paul Saka (1998), both of whom are indebted to the Demonstrative and Identity accounts.My reasons for using Recanati (2001) as the backbone of my own theory are the following. Recanati has successfully drawn the line between two types of meaning conveyed by metalinguistic demonstrations, namely ‘pictorial’ and ‘conventional linguistic’ meaning, something that had not been done with that clarity before. Besides, he has had the wisdom to give up the standard assumption that all metalinguistic demonstrations are referential, an assumption that inevitably led to theoretical dead ends. Moreover, drawing on the first two insights, Recanati has also separated out the syntactic and pragmatic aspects that were often confused in previous approaches.There is no doubt that the theory put forward by Recanati in 2001 is the most empirically adequate that can be found in the literature. Besides, it also accounts for an impressive range of key properties. Still, there are two interesting properties that received very little attention from Recanati, that is, referential diversity and recursiveness. Though Paul Saka has argued in favour of both in a 1998 paper, I believe his defence to have been somewhat clumsy. And therefore I have tried to offer more convincing evidence in favour of these properties.Let’s start with ReferenceAs Recanati has shown, not all metalinguistic demonstrations are referential expressions. But there is one aspect of reference that he says very little about: the sort or sorts of referents that a referential autonym can have. The theory implicitly suggests that autonyms can only refer to types. (Many writers have claimed more robustly and more explicitlythat there was only one sort of referents for autonyms, always either types or classes of tokens).I hold this view to be incorrect. As I’ve indicated in Chapter 4 of the thesis, I believe that several sorts of referents must be distinguished. Let us have a few examples:Run is a verbRun has three lettersShe said, “I ain’t EVER gonna tell ya”The first refers to a lexeme, since the predicate applies to runs, ran, running, as well.The second, only to a form (since not true of running or runs).Both could still be said to be abstract objects, and one might wish to call these ‘types’.The third, however, well and truly seems to refer to a token, the particular utterance produced by the woman behind she, witness the mimicry involved in the direct speech report.In my discussion of the next property, I offer a further argument in favour of referential diversity.2. Metalinguistic demonstrations can be iterated (repeated), a property usually described as recursiveness, and which has given rise to some controversies. Some demonstrativists, notably Cappelen & Lepore, because they hold the interior of a quotation to be semantically inert, have rejected the idea of recursiveness. I think, however, that their rejection comes from their failure to discern several types of recursiveness. In my dissertation, I have distinguished three; I shall only sketch two here.“ ‘Boston’ ” is an autonym.Typographical recursiveness: hardly very interesting, since it is a mechanical operation that can be repeated at will.The next pair of examples throws a more interesting light on the matter:‘Boston’ is a six-letter word.In each utterance of the previous example, “ ‘Boston’ ” is used to refer to an orthographic formBoston enclosed in two pairs of quote marks refers to particular tokens of Boston in a single pair of quote marks, as are produced when uttering a token of the first sentence, ‘Boston’ is a six-letter word. In each utterance of that sentence, the subject, ‘Boston’, itself refers, this time to the name Boston. This means that we have a situation in which an autonym refers to another autonym which also refers: reference here is iterated.This is actually no problem for the assumption of the inertness of the interior of the quotation, because reference is directed outwards: the interior of the quotation itself (the token displayed) remains inert. Note that referential recursiveness is only possible when one has a meta-quotation that refers to a token that is itself a referential autonym. This confirms the need for the theory to accommodate reference to particular tokens.I have made further use of the theory of metalinguistic demonstrations in Chapter 6 of the thesis, which is devoted to sketching a typology of metalinguistic demonstrations. In this connection, I have tried to bring together different types of discriminating factors that had been used in previous classifications (syntactic, semantic, pragmatic, typographical, lexical). These did not seem to be compatible from the outset, but then I realised that they might perhaps all be integrated into a single typology if I adopted an interpreter’s perspective. I reflected that that perspective provided a criterion for determining which characteristics of metalinguistic demonstrations would count as relevant variables for a typology: only those that made a ‘difference for the interpreter’ (i.e. affected his/her interpretative processes) would be retained.I also took advanatge of the general theory for the interpretation of utterances that has been set out in some recent publications, notably by Bach and Recanati (and which I outline in Chapter 3 of the thesis), and eventually reached what I regard as a decent result. Moreover, I also made a couple of interesting discoveries. The first one is that quite a bit of the interpretation of an utterance takes place at a ‘pre-interpretative’ level, that is, befor a sentence has been clearly identified (disambiguated). In particular, there are significant pictorial aspects of metalinguistic demonstrations that enter into the disambiguation process rather than into interpretation proper. The second one is that there is an impressive number of aspects of meaning that are linked to the speaker’s intentions, and should theoretically require access to the wide context of an utterance to be processed, that can be accessed at very low (semantic) levels of interpretation.In the final part of this presentation, I wish to examine a couple of instances of hybridity that face the theory with a more serious challenge than example 5 on the first slide. That example was easily explained in terms of simultaneous use and mention (the standard account in the literature): the same sequence, military action, was used ordinarily and, secondarily, demonstrated as being a particular form of euphemism. Other hybrids, on the other hand, do not lend themselves to such an analysis in a straightforward way. The first example I wish to bring up raises an interesting problem in connection with the notion of grammaticality:Robbe-Grillet describes himself in his introduction as “volontiers professeur de moi-même”.This can be rewritten as a pair of sentences, one for use the other for mention. We get:Use :Robbe-Grillet describes himself in his introduction as volontiers professeur de moi-même.Mention :Robbe-Grillet uses the expression “volontiers professeur de moi-même”.Although the mention line raises no special issues, there are great doubts as to the grammaticality of the ordinary-use line: a language-shift occurs in the middle of the sentence, and is not signalled by any marker, unlike in the initial hybrid. Though Recanati’s framework allows for language-shifts, and could therefore be relied on to argue that the correct interpretation can be ascribed to the French words in the example, it does not state rules determining at which spot in an utterance such a shift is acceptable grammatically. In other words, it says nothing about the possibility of a grammar that would straddle English and French. Fortunately, the idea of such grammars is supported by the limited research that has been carried out about code-switching. So, there may be theoretical backing for the assumption that the use line may after all be grammatical (with respect to a hybrid grammar).Note that these remarks are valid, I believe, not just for the use line of the twofold paraphrase, but for the initial hybrid too. Indeed, it is not clear — though some would be ready to say so — that the presence of quote marks is enough to alter the grammaticality of an utterance.Note also that an example like the previous one is a reminder of an essential fact about the work of language scholars: they start out to describe and/or explain some empirical data they find significant. But as things get more complicated, they must continually make decisions as to what must be acknowledged as relevant data for their research. Every step of the way, there may be a temptation to dismiss data — in the present case, on grounds of ungrammaticality — because these data threaten the validity of the theory being devised. Here, thanks to an analogy with grammatical accounts of code-switching, a case can be made for the grammaticality of utterances like the one under consideration. It is these kinds of extensions that broaden the linguist’s horizons and make research worthwhile.The second example I wish to examine raises interesting issues concerning iconicity. Though I have said nothing about it so far, iconicity is perhaps the single most important notion in any discussion of metalinguistic demonstration. In a nutshell, the basic assumption about ‘how such a demonstration makes sense’ is that the tokens displayed in a mentioning utterance are iconically related to the target of the demonstration. Iconicity can initially be understood as a matter of formal resemblance (cf the first batch of examples on Slide 1). The following example shows that the notion must be made more flexble than that:Descartes said that man “is a thinking substance”.Use: Descartes said that man is a thinking substance.Mention: Descartes said “is a thinking substance”.It can be seen that the mention line of the paraphrase is truth-conditionally incorrect: Descartes did not produce a token of is a thinking substance, since he was writing in Latin, not English. What Descartes said was est res cogitans. This might be taken to imply that the relation between the English tokens displayed and the Latin target is not a matter of iconicity. I would, with several other writers, suggest another direction: There is iconicity in this example, but the concept must be understood to be flexible and adaptable to contextual constraints. I believe such a conception to be necessary if one wants to be able to account for metalinguistic demonstrations within a single explanatory framework. There are too many instances of quotations that are not supported by formal identity to maintain a rigid notion of iconicity. I have added a last example on the slideConclusionAlthough I originally aspired to a comprehensive survey of things metalinguistic, I cannot but concede that there are still multiple aspects of the reflexive use of language that need looking into. I believe, however, that I have been able to shed some light on some areas of the debate. For instance, I believe that my discussion of the recursiveness and referential diversity of autonyms goes one step further than previous discussions. In particular, I hope to have been able to show convincingly that, contrary to a widespread opinion, an autonym can refer to various object, notably individual tokens. When these results are added to an excellent theory like Recanati’s, one ends up with a powerful explanatory apparatus. Moreover, this apparatus has the added advantage that it can easily be integrated into the general theory for the interpretation of utterances which I have alluded to before.I have taken advantage of this compatibility to outline my interpreter’s typology of metalinguistic demonstrations. Whether that effort was entirely successful or not, I think it has incidentally provided an excellent testing ground for the general theory. If only in that respect, the attempt was worth a try, since it shed light on the importance of pre-interpretative processes and on the conventional encoding of aspects of meaning that are otherwise heavily dependent on speaker’s intentions.Finally, I believe that the work doen in Chapter 8 has brought to the fore a number of question that deserve to be investigated at greater length in future. There are still dark areas in the study of world/language hybrids, but there also more general questions, e.g. regarding grammaticality and iconicity that need looking into. / Doctorat en philosophie et lettres, Orientation langue et littérature / info:eu-repo/semantics/nonPublished

This dissertation investigates the comprehension of indirect requests (IRs). Focusing on English and French, it proposes that IRs such as Can you + verbal phrase (for short, Can you VP?) achieve an optimal communicative efficiency because, while they entail extra processing costs, they match the expected level of politeness in many contexts. The approach taken combines Talmy’s force dynamic semantics with a traditional perspective in philosophy of language drawing on speech act theory. First, I sketch a theoretically viable and empirically plausible definition of directive speech acts, and provide a naturalistic explanation of why directives result in obligations for addressees. According to this definition, a directive speech act consists in a force exerted by a speaker towards an addressee’s performance of some action, with a prima facie obligation created for the addressee as a result. Consistently with this definition, I propose that imperative sentences are a convenient means to perform directives insofar as they encode a force dynamic pattern that is compatible with, but distinct from, the force exertion pattern that characterizes directives. I develop a similar analysis for You should/must VP declarative sentences. By contrast, I argue that, if interrogative sentences can be used in the performance of directives such as questioning, they do so by virtue of their incompleteness.To satisfactorily account for the variety of utterances that can be used as directives, I propose a typology based on the formal criterion of (in)directness and on the processing criterion of primariness/secondariness. Three factors are furthermore predicted to influence the processing of IRs: conventionality of means, degree of standardization, and degree of illocutionary force salience. This typology underpins an exhaustive review of experimental work on the comprehension of directives, in which I conclude that further investigation into the processing of IRs is necessary. In particular, the influence of these three factors on the processing, and, in particular, on the primariness/secondariness of IRs is left unexplored.In three eye-tracking experiments with native speakers of French, I put to the test four hypotheses. First, I hypothesize that the more an expression is standardized for the performance of IRs, the more likely it will be understood as an IR, and the more likely the IR will be primary rather than secondary. Second, because expressions such as Can you VP? used as IRs also have a direct interpretation, they should entail extra processing costs relative to their imperative and interrogative direct counterparts. Third, assuming they are direct, You must VP requests should be understood like imperatives requests, and they should not activate the assertive force. Fourth, the high degree of directive illocutionary force salience contributed by the adverb please should increase the likelihood of an IR interpretation and the likelihood that the IR will be primary. In Experiment 1, I show that IR interpretations tend to be more frequent for highly standardized IRs relative to their less standardized counterparts. I also demonstrate that interpreting the highly standardized Can you VP? and the less standardized Is it possible to VP? as IRs does not activate their “ability question” illocutionary meaning. The same finding holds, in Experiment 2, for the declaratives You can VP and It is possible to VP. The data of Experiment 2 indicate that, like imperative sentences, You must VP does not activate the assertive illocutionary force. Another finding of Experiment 1 is that Can you VP? and Is it possible to VP? can be understood as primary IRs, but these expressions nonetheless impose extra processing costs when they are interpreted as direct questions. In Experiment 3, I find that the high degree of directive force salience contributed by please increases the likelihood of an IR interpretation regardless of the degree of standardization of the expression. However, the presence of please has no significant influence on the processing of IRs.Turning to the production of directives, I address the issue of why speakers use IRs despite the extra processing costs entailed by these expressions. In a production task experiment where addressee status is manipulated, I test the hypothesis that Can you VP? IRs are used to trigger extra politeness effects absent in imperatives. A second hypothesis is that speakers should avoid imperatives and obligation declaratives such as You should/must VP because these request forms are directly compatible with force exertion at the pragmatic level. Rather, they should prefer indirect request forms such as ability interrogatives. Third, Can you VP? it should be more frequent than Is it possible to VP? in the data. A first important finding is that higher addressee status does not increase the frequency of Can you VP? interrogatives relative to other request forms. Instead of using Can you VP? more often when they address higher status people, speakers use specific politeness markers, which disconfirms the hypothesis that Can you VP? is used to convey extra politeness effects. The second hypothesis is confirmed, insofar as the data collected with this production task contain a vast majority of ability interrogatives, and imperatives and obligation declaratives are absent. Third, in line with the standardization hypothesis, Can you VP? occur much more often in the data than Is it possible to VP?. / Doctorat en Langues, lettres et traductologie / info:eu-repo/semantics/nonPublished

Le développement de salissures marines (ou biofouling) est à l’origine de nombreux problèmes économiques et écologiques. Ces salissures marines sont constituées de microorganismes (bactéries, microalgues…) formant le microfouling sur lequel va se développer le macrofouling constitué de macroorganismes tels que les algues, coquillages et éponges. La formation de ces salissures va induire un ralentissement des navires provoquant une surconsommation de carburant. De plus, l’utilisation de revêtements antisalissures ou peintures antifouling à base de métaux lourds et de biocides dans le passé a conduit à des problèmes environnementaux. L’objectif de la thèse est de rechercher une alternative aux composés actuellement utilisés (cuivre) en respectant le milieu marin. L’environnement est une source d’inspiration, une approche biomimétique pourrait être une stratégie de lutte efficace contre le biofouling. Dans une première partie, un criblage d’une centaine de composés est réalisé contre des souches bactériennes. Huit composés issus des deux familles : les batatasins et les hemibastadins sont étudiées en vue de comprendre leurs modes d’action. Parmi les composés sélectionnés, la famille des hemibastadins comprenant le DiBromoHemiBastadin-1 (DBHB) a montré des propriétés antifouling prometteuses. En effet, cette molécule est capable d’inhiber 50 % la formation du biofilm avec une IC50= 6,44 µg/mL pour la bactérie Pseudomonas aeruginosa PAO1 et une IC50 = 12,8 µg/mL pour la bactérie marine Paracoccus sp. 4M6. Afin de comprendre le mode d’action de cette molécule, son impact sur la communication bactérienne, le quorum sensing est étudié et le composé DBHB est capable de l’inhiber. Dans une seconde partie, un autre groupe d’organismes participant au microfouling est étudié : les microalgues. Afin d’évaluer l’impact de composés de la famille des hemibastadins et notamment du DBHB, l’adhésion et la formation de biofilm de microalgues sont étudiées. Le DBHB montre des inhibitions de l’adhésion et de la formation du biofilm uniquement envers la diatomée Cylindrotheca closterium. Une dernière partie, s’est intéressée à l’évaluation de revêtements contenant six composés de la famille des batatasins et des hemibastadins sur le microfouling naturel. Une méthode d’immersion de revêtements en conditions contrôlées (photobioréacteur) est mise au point afin de pallier aux contraintes environnementales. L’ensemble de cette étude a permis de mettre en évidence les propriétés antifouling du DBHB et de caractériser son mode d’action. Ce composé offre d’intéressantes voies d’étude dans la lutte contre le biofouling. De plus, l’approfondissement des connaissances sur les procédés d’adhésion et de formation de biofilm de microalgues permet de définir de nouvelles stratégies de lutte. / Biofouling induces important economic and ecological problems. This phenomenon includes microorganisms (bacteria, microalgae…) giving the microfouling which allows the macrofouling development with algae, invertebrates and sponges. These organisms colonize every immersed surface as boat hull. The colonization induces reduced speed of ships and fuel overconsumption. In the past, the utilization of AF coatings with heavy metals or pesticides caused environmental problems. The purpose of the study is to find an alternative to AF compounds (copper) respecting the marine medium. The marine environment is an inspiration; a biomimetic approach could be an interesting strategy to inhibit biofouling. In a first part, a screening of one hundred compounds is realized against marine and terrestrial bacteria. Eight molecules from two families (batatasins and hemibastadins) are studied to understand the way of action. Among selected compounds, Dibromohemibastadin-1 (DBHB) from hemibastadin family shows promising AF activities. This molecule is able to inhibit the biofilm formation with an IC50 of 6,44 µg/mL against the bacterium Pseudomonas aeruginosa PAO1 and 12,8 µg/mL for the marine bacterium Paracoccus sp. 4M6. To identify the way of action of DBHB, the impact on the bacterial communication named quorum sensing is investigated. The molecule shows an anti-quorum sensing property. In a second part, another group participating at microfouling is studied: microalgae. In order to evaluate the impact of hemibastadin family in particular DBHB, microalgae adhesion and biofilm formation are characterized. DBHB induces inhibition only on the adhesion and the biofilm formation of the diatom Cylindrotheca closterium. The last part presents the formulation of coatings containing six compounds from the batatasin and hemibastadin families. These coatings have been immersed in a harbor to evaluate the impact on natural microfouling. Furthermore, a new method for the evaluation of AF coatings is developed in controlled conditions, in a photobioreactor. This method allows the evaluation of coatings on the formation of a mixed biofilm (bacteria and microalgae). This method has been established to avoid environmental constraints by immersion in natural condition. This study allows the characterization of the AF property of DBHB. This compound provides promising research path to limit biofouling. Moreover, the development of a test allowing adhesion and microalgae biofilm formation in dynamic condition improves the characterization of compounds activities.