La masse de la baie est le résultat de l’effet intégré de plusieurs facteurs. La recherche a été dessinée afin d’étudier l’effet simultané des facteurs majeurs influençant la masse et la composition de la baie, de les hiérarchiser selon leur degré d’impact à des échelles différentes, de séparer leur effet direct et indirect sur la composition du raisin et de comparer le profil de vins élaborés à partir de petites et grosses baies. L’étude a été conduite sur deux sites expérimentaux, localisés dans les régions de Saint-Emilion (France) et Alcamo (Italie), pendant les années 2014 et 2015. Sur le premier site, les vignes sont plantées sur deux types de sols, tandis que sur le deuxième, deux traitements hydriques étaient appliqués. A l’échelle intra-parcellaire, l’état hydrique de la vigne représente le facteur le plus important, tandis que l’effet du nombre de pépins par baie n’est pas significatif. Des résultats opposés sont obtenus lorsque les relations sont étudiées à l’échelle de la grappe et de la plante. A large échelle, les facteurs impactent directement et indirectement la composition du raisin et les petites baies produisent des moûts et des vins plus concentrés. A l’inverse, à l’échelle de la grappe et de la plante, la masse de la baie n’influence pas la composition du raisin. Seule la concentration en anthocyanes est significativement liée à la masse à toutes les échelles. Cette relation est particulièrement évidente sous conditions hydriques limitantes. Un déficit hydrique augmente le ratio pellicule/pulpe, indépendamment de la masse de la baie. Petites et grosses baies d’une parcelle ayant une condition hydrique homogène, tendent à avoir un profil similaire. / Final berry mass is the result of the integrated effect of several factors. They also influence berry composition. The present work was designed to study the simultaneous effect of major factors influencing berry mass and composition, to hierarchize their impact at different scales, to distinguish their direct and indirect effect on berry composition and to compare the profile of wines made from large and small berries. The study was carried out simultaneously on two vineyards located in the Saint Emil ion (France) and Alcamo (Sicily) areas, during 2014 and 2015. On the first site, vines were planted on two soil types, while on the second site two different irrigation treatments were applied. Depending on the scale, some factors homogeneously impacted the berry mass and composition. At the intra-parcel scale, vine water status represented the most impacting factor, while berry seed number did not have significant effect. Opposite results were obtained when the investigation was carried out at the intra-bunch and intra-plant scales. At large scale, factors impacted directly and indirectly berry compounds and grape juices and wines produced from smaller berries were more concentrated. Neither at intra-bunch, nor at intra-plant scales, berry size effect on juice composition was significant. Only anthocyanin concentration was related to berry size at all scales. This fact was particularly obvious in berries produced under limited water conditions. Water deficit increased the skin to flesh ratio, independently of berry size. This means that small and large berries, produced from a single parcel with homogenous water uptake conditions, tend to have similar enological profiles.

L’objet de cette thèse concerne l’étude asymptotique des processus de branchement sur-critiques en environnement aléatoire, qui sont une généralisation du processus de Galton-Watson, avec une loi de reproduction choisie aléatoirement et de manière i.i.d. suivant les générations. Dans le cas de non extinction, nous démontrons une succession de résultats asymptotiques plus fins que ceux établis dans des travaux antérieurs. Le chapitre 1 est consacré à l’étude de l’écart relatif entre le processus (Zn) normalisé et la loi normale. Nous établissons une borne de type Berry-Esseen ainsi qu’un développement pour des déviations de type Cramér, généralisant ainsi le théorème central limite et le principe des déviations modérées établis précédemment dans la littérature. Le second chapitre concerne l'asymptotique de la distribution du processus (Zn) ainsi que le moment harmonique critique de la variable limite W de la population normalisée. Nous établissons un équivalent de l'asymptotique de la distribution du processus Zn et donnons une caractérisation des constantes via une équation fonctionnelle similaire au cas du processus de Galton-Watson. Dans le cas des processus de branchement en environnement aléatoire, les résultats améliorent l'équivalent asymptotique de la distribution de Zn établi dans des travaux antérieurs sous normalisation logarithmique, sous la condition que chaque individu donne naissance à au moins un individu. Nous déterminons aussi la valeur critique pour l'existence du moment harmonique de W sous des conditions simples d'existence de moments, qui sont bien plus faibles que les hypothèses imposées dans la littérature, et généralisons le résultat à Z_0=k individus initiaux. Le troisième chapitre est consacré à l'étude de l'asymptotique des moments harmoniques d'ordre r>0 de Zn. Nous établissons un équivalent et donnons une expression des constantes. Le résultat met en évidence un phénomène de transition de phase, relié aux transitions de phase des grandes déviations inférieures du processus (Zn). En application de ce résultat, nous établissons un résultat de grandes déviations inférieures pour le processus (Zn) sous des hypothèses plus faibles que celles imposées dans des travaux précédents. Nous améliorons également la vitesse de convergence dans un théorème central limite vérifié par W_n-W, et déterminons l'asymptotique de la probabilité de grandes déviations pour le ratio Zn+1/Z_n. / The purpose of this Ph.D. thesis is the study of branching processes in a random environment, say (Z_n), which are a generalization of the Galton-Watson process, with the reproduction law chosen randomly in each generation in an i.i.d. manner. We consider the case of a supercritical process, assuming the condition that each individual gives birth to at least one child. The first part of this work is devoted to the study of the relative and absolute distance between the normalized process log Z_n and the normal law. We show a Berry-Esseen bound and establish a Cramér type large deviation expansion, which generalize the central limit theorem and the moderate deviation principle established for log Z_n in previous studies.In the second chapter we study the asymptotic of the distribution of Z_n, and the critical value for the existence of harmonic moments of the limit variable W of the normalized population size. We give an equivalent of the asymptotic distribution of Z_n and characterize the constants by a functional relation which is similar to that obtained for a Galton-Watson process. For a branching process in a random environment, our result generalizes the equivalent of the asymptotic distribution of Z_n established in a previous work in a log-scale, under the condition that each individual gives birth to at least one child. We also characterize the critical value for the existence of harmonic moments of the limit variable W under weaker conditions that in previous studies and generalize this result for processes starting with Z_0=k initial individuals. The third chapter is devoted to the study of the asymptotic of the harmonic moments of order r>0 of Z_n. We show the exact decay rate and give an expression of the limiting constants. The result reveals a phase transition phenomenon which is linked to the phase transitions in the lower large deviations established in earlier studies. As an application, we improve a lower large deviation result for the process (Z_n) under weaker hypothesis than those stated in the literature. Moreover, we also improve the rate of convergence in a central limit theorem for W-W_n and give the asymptotic of the large deviation for the ratio Zn+1/Z_n.

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The decades following the collapse of the Soviet Union have seen an increased interest in uncovering the relationship between New Negro era authors and intellectuals and the radical leftism that had such a widespread influence in the twentieth century. Scholars are reanalyzing the life and works of figures like Claude McKay, Langston Hughes, W.E.B. Du Bois and others in light of each author's interaction with and acceptance of communist and socialist ideals. These studies trace these radical connections in an effort to better understand New Negro authors and their work during a time of revolution and social upheaval. There is still much work to be done, however, in the study of those African American authors who were not directly allied with these movements, but nonetheless were vital voices in the radical atmosphere of the time. One such author is Wallace Thurman, an influential editor and writer who is connected to communism and socialism in undeniable ways, but also seems ideologically distant from his radical leftist peers. Examining Thurman's body of work as a part of a larger revolutionary trend reveals that though his views differed from and often reacted against communist rhetoric as he understood it, Thurman did use that rhetoric to form his own radical ideology. Thurman's most famous novel, The Blacker the Berry, gives insight into both the radical change that the author hoped for, as well as his vision of the best way to bring about that change. The novel's protagonist, Emma Lou Morgan, represents those individuals who cannot quite manage to fit into a mass movement because her dark skin and psychological issues with her own race and skin color prevent her from easily molding herself to the ideals of others. Emma Lou's struggle for mental independence reveals that though Thurman longed for large-scale, radical reform, he also insisted that no such reform was possible without first helping individuals to overcome their personal psychological barriers. This study of Thurman and his radicalism not only shows that not all revolutionaries of the time were communists, it also begins the work of tracing a New Negro radicalism that was connected to the communist and socialist movements, but also included veins unique to each author's social, racial, and geographic position.

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The prominent features of single molecule magnets (SMMs), such as the quantum tunneling of the magnetization (QTM), are conventionally understood through the giant spin approximation (GSA) which considers the molecule as a single rigid spin. This model often requires the inclusion of high order anisotropy terms in the Hamiltonian, a manifestation of admixing of low lying excited states that can be more naturally understood by employing a multi-spin (MS) description i.e. considering the individual spins and the interactions between ions within the molecule. However, solving the MS Hamiltonian for high nuclearity molecules is not feasible due to the enormous dimensions of the associated Hilbert space that put it beyond the capability of existing computational resources. In contrast, low nuclearity systems permit the complete diagonalization of the MS Hamiltonian required to sample the effect of internal degrees of freedom, such as exchange interactions and single ion anisotropies, on the QTM. This dissertation focuses on the study of low nuclearity SMMs in view of understanding these subtle quantum effects. To accomplish this, we have developed a series of magnetic characterization techniques, such as integrated microchip sensors resulting from the combination of two dimensional electron gas (2DEG) Hall-Effect magnetometers and microstrip resonators, capable of performing measurements of magnetization and EPR spectroscopy simultaneously. The thesis bases on a comparative study of two low nuclearity SMMs with identical magnetic cores (Mn4 dicubane) but differing ligands. Notably, one of these SMMs lacked solvent molecules for crystallization; a characteristic that gives rise to extremely sharp resonances in the magnetization loops and whose basic QTM behavior can be well explained with the GSA. On the contrary, the second SMM exhibited mixed energy levels, making a MS description necessary to explain the observations. We have also examined the role of internal degrees of freedom on more subtle QTM phenomena, leading to the explanation of asymmetric Berry-phase interference patterns observed in a Mn4 SMM in terms of a competition between different intermolecular magnetic interactions, i.e. non-collinear zero-field splitting tensors and intramolecular dipolar iii interactions, resulting in astonishing manifestations of the structural molecular symmetry on the quantum dynamics of the molecular spin.

Published in 1977, Wendell Berry's book The Unsettling of America: Culture and Agriculture gained widespread popularity. More than half a century later, many of the notions of the body and the earth presented in its seventh chapter, "The Body and the Earth," remain relevant and important for environmental discourse today. Berry's discussion of the body and the earth examines their mutuality and codependence from an ontological, theological, agricultural, and even biological perspective. The coupling of this text with Judith Butler's, Frames of War: When is Life Grievable? contemporizes his argument through its more socio-political and philosophical claims regarding life and the body. Through the discussion of societal frames that often prescribe the value of life and bodies, Butler introduces the concept of precarity, or the imposition of violence and its resultant instability of the body. Driven by the external forces of society, precarity weakens, commodifies, and exploits the body, creating unsustainable social systems. As we learn from Berry, this bodily precarity parallels the violence and mistreatment of the earth. The body, and its ecological and anthropological interconnectedness, establishes both material and immaterial ties to the earth, suggesting that any damage done to the body affects not just itself, but the entire system. In bringing together Butler and Berry through an ecocritical dialogue, a new ethic regarding the formation and meaning of a life emerges, prompting revision of the current societal parameters that establish the definitions of the body and the earth. Berry's resurgent relevance comes from his admonitions to repair the relationships of all bodies and the networks of which they are a part. Thus, the connection between an individual and their body, other bodies, and the earth must be restored for an environmental ethic to both persist and establish productive environmental change.

In absence of external fields, vibrational modes of periodic systems are usually considered as linearly polarized and, as such, they do not carry angular momentum. Our work proves that non-adiabatic effects due to the electron-phonon coupling are time-reversal symmetry breaking interactions for the vibrational field in systems with non-collinear magnetism and large spin-orbit coupling. Since in these systems the deformation potential matrix elements are necessarily complex, a nonzero synthetic gauge field (Berry curvature) arises in the dynamic equations of the ionic motion. As a result, phonon modes are elliptically polarized in the non-adiabatic framework and intrinsic vibrational angular momenta occur even for non-degenerate modes and without external probes. These results are validated by performing fully relativistic ab-initio calculations on two insulating platinum clusters and a metallic manganese compound, with non-collinear magnetism. In both cases, non-adiabatic vibrational modes carry sizeable angular momenta comparable to the orbital electronic ones in itinerant ferromagnets.

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