Dans le cadre du programme de renouvellement des approches en histoire de l’art grec mis en place dans l’équipe de recherche PLH-CRATA, je me suis engagée dans une thèse sur « L’aspective sur la céramique attique du VIIIe siècle av. J.-C. au premier quart du VIe siècle avant J.-C. ».Ce concept, élaboré par les égyptologues, désigne une construction de l’image qui n’est pas régis par le procédé de la perspective. Les différentes techniques de représentation en perspective ont toutes pour buts de représenter la vue d’objets en trois dimensions sur une surface donnée, en tenant compte des effets de l’éloignement et de leur position dans l’espace par rapport à l’observateur. Les Grecs nous ont légué leur vision perspective avec des figures conçues depuis un seul endroit en un seul moment. Toutefois, ce mode de représentation ne s’est mis en place que très progressivement, entre la fin du VIe siècle et le milieu du Ve siècle. Avant cette période, l’art de nombreuses cultures est régi par les principes de l’aspective. Cette notion associe plusieurs points de vue dans la représentation d’un même personnage. Elle peut aussi regrouper plusieurs moments d’une même histoire dans une image unique. L’artisan représente les parties comme si chacune d’entre-elles était isolée, s’affranchissant du regard subjectif de l’observateur. Il y a bien dans l’art archaïque grec une aspective. Il faut en déceler la présence, mais aussi en dégager les spécificités. C’est à cette tâche que je me consacre, dans une thèse conçue avec des gros plans sur certaines périodes clés. Les résultats sont particulièrement étonnants, puisqu’ils mettent en évidence, dans l’art géométrique, une présence plus marquée des procédés perspectifs qu’au VIIe et VIe siècle, au sein d’une image construite, par ailleurs, selon des procédés aspectifs. Les résultats montrent ainsi que, dès le départ, les deux conceptions de l’espace graphique connaissaient des interpénétrations. / As part of the renewal program study of history of Greek art developed in the research team PLH-CRATA, I am carrying out a thesis entitled : « The aspectivity in attic vase-painting : 900 – 575 ».This concept, elaborated by Egyptologists, refers to the construction of the image in graphic spaces which are not governed by perspective. Aspectivity is a close but distinct notion of what Waldemar Deonna called "primitivism". The perspective vision is the one that is natural for us. All the different techniques of perspective representation have in common the intention of representing the view of objects in three dimensions on a given space. They take into account the effects of the distance and the position in space with respect to the observer. The Greeks bequeathed us their perspective vision with figures conceived from a single place in a single moment. This representation is at the origin of the spatial and temporal unity. However, this mode of representation only took place very gradually between the end of the 6th century and the middle of the 5th century.Before this period, the art of many cultures is governed by the aspective principles. This notion, belonging to semiology, associates several points of view in the representation of the same character, whereas in natural vision we have only one. The aspective can also group together several moments of the same story in a single image, which can be read in one moment. The artist represents the parts as if each of them was isolated, as an enumeration of the various characteristics of the subject, freeing themselves from the subjective gaze of the observer placed in a certain place. The works do not seek to show a representation in time and space, but to show what must be, even if the events are not linked in time. The image becomes more a construction than a representation.There is, in Greek archaic art, as in the Egyptian and Near Eastern arts, an aspective. It is necessary to detect its presence, but also to identify its specificities. It is to this task that I dedicate myself, in a thesis conceived with close-ups on certain important periods. The results are particularly surprising, since they show, in the art of the Geometric period, a stronger presence of perspective processes that in the seventh and early sixth century BC. J.-C. within an image constructed otherwise by aspective processes. The results thus show that, from the start, the two conceptions of graphic space know some interpenetrations.

Orientador: Enes Furlani Jr. / Banca: Salatiér Buzetti / Banca: Edison Martins Paulo / Resumo: Novas tecnologias de produção agrícola buscam melhores condições de higiene, diminuição na incidência de doenças do solo e alternativa para a falta de espaço, ultrapassando obstáculos e incrementando a produção de muitas culturas, oferecendo vantagens que o produtor encontra na utilização de recipientes para o cultivo de hortaliças em estufas. Esse trabalho teve como objetivo avaliar diferentes recipientes e concentrações de cálcio na solução nutritiva no cultivo do tomateiro em substrato de fibra de coco em ambiente protegido. O experimento foi desenvolvido de abril a setembro de 2008 na área experimental da Fazenda de Ensino, Pesquisa e Extensão da Faculdade de Engenharia - UNESP, Campus de Ilha Solteira - SP. Os tratamentos constaram de quatro recipientes (calha, vaso pequeno, vaso grande e travesseiro) e cinco concentrações de cálcio (0,052 g/L, 0,065 g/L, 0,078 g/L, 0,091 g/L e 0,104 g/L). Efetuaram-se as seguintes avaliações: análise química do tecido foliar, número de frutos com podridão apical, produção total e comercial, massa média de frutos comerciais e classificação de frutos. Conclui-se que nas condições do trabalho o recipiente calha proporcionou maior produtividade de frutos médios quando comparado com o recipiente vaso grande. A antecipação da colheita pode estar relacionada com a temperatura mais elevada ocorrida no ambiente protegido, onde foram cultivadas as plantas do híbrido Débora Max. Os recipientes não foram fatores limitantes para produção. O cálcio e o potássio apresentaram sinergismo, houve inibição competitiva do cálcio sobre a absorção do potássio. Em relação à adubação com concentrações de cálcio, as concentrações de 0,052 e 0,065 g/L foram responsáveis por maior produção total e comercial, maiores números de frutos pequenos e graúdos e maior número de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: New technologies of agricultural production seek better conditions of hygiene, reduction in the incidence of soil diseases and alternative for the lack of space, overcoming obstacles and increasing the production of many cultures, offering benefits that the producer is the use of containers for growing of vegetables in greenhouses. This study aimed to evaluate different containers and calcium concentrations in the nutrient solution in the tomato crop of coconut fiber in a greenhouse. The experiment was conducted from April to September 2008 at the experimental farm of Education, Research and Extension, Faculty of Engineering - UNESP, Ilha Single - SP. The treatments consisted of four containers (rail, small vessel, large vessel and pillow) and concentrations of calcium (0.052 g / L, 0.065 g / L, 0.078 g / L, 0.091 g / L and 0.104 g / L). We carried out the following assessments: chemical analysis of leaf tissue, number of black spot, total and marketable yield, average fruit weight and fruit classification business. We conclude that under the conditions of the working chute container provided higher average fruit yield compared to the large container vessel. The early harvest may be related to the higher temperature occurred in the greenhouse, where plants were grown hybrid Deborah Max containers were not limiting factors for production. Calcium and potassium showed synergism, there was competitive inhibition of calcium on the absorption of potassium. In relation to fertilization with concentrations of calcium, concentrators 0.052 and 0.065 g / L were responsible for greater total output and trade, greater numbers of small fruit and old and greater number of commercial fruits, and provide better control of the incidence of black spot. / Mestre

Im Rahmen dieser Diplomarbeit wurde eine Ultrahochvakuumanlage für organische Molekularstrahldeposition (OMBD) konzipiert und gefertigt, die das Aufwachsen von einzelnen organischen Schichten bis hin zu komplexen Schichtsystemen auf geeigneten Substraten erlaubt. Mit einem ebenfalls konzipierten und gefertigten Probenhalter, sind elektrische Messungen in situ möglich. Für weitere Charakterisierungsmethoden, wie der spektroskopischen Ellipsometrie und der Reflexions-Anisotropie-Spektroskopie sind ebenfalls Optionen für in-situ-Messungen an der UHV-Anlage vorgesehen. Mit dieser Anlage wurden einzelne organische Schichten von Zinkphthalocyanin (ZnPc), Fulleren C60 und Bathocuproin (BCP) hergestellt, die anschließend mit spektroskopischer Ellipsometrie ex situ untersucht wurden. Mit der Herstellung organischer Solarzellen, auf Basis der zuvor hergestellten organischen Einzelschichten, konnte gezeigt werden, dass mit der UHV-Anlage komplexe organische Schichtsysteme erzeugt werden können, an denen in-situ-elektrische Messungen durchführbar sind. / Within the scope of this diploma thesis, a ultra high vacuum chamber for organic molecular beam deposition (OMBD) was designed and built, which allows the growth of single organic layers and complex composit layer structures. With an also designed and built sample holder, it is possible to make in situ electrical measurements. Single organic layers of zinc-phthalocyanine (ZnPc), fullerene C60 and bathocuproine (BCP) were deposited inside this chamber and characterized ex situ by spectroscopic ellipsometry. The preparation of an organic photovoltaic (OPV) cell based on the before characterized single layers, demonstrates that it is possible to deposit complex layer structures and characterize them electrical in situ.

In the scope of this diploma thesis the optical properties of organic multilayers and mixed layers were investigated by means of spectroscopic ellipsometry und infrared spectroscopy. The samples were prepared by organic molecular beam deposition in high vacuum on hydrogen passivated Silicon(111) substrates. The structures consist either of N,N-Di(naphthalene-1-yl)-N,N`-diphenyl-benzidine (a-NPD) and tris(8-hydroxyquinoline) aluminium (Alq3) or 3,4,9,10-perylene-tetracarboxylic dianhydride (PTCDA) and copper phthalocyanine (CuPc). The optical response of the multilayers consisting of Alq3 and a-NPD could be modelled using the isotropic dielectric functions of single layers assuming sharp interfaces. The planar structure of PTCDA and the CuPc molecules and their orientation in the stack lead to an overlapping of the p-orbitals strongly influencing the optical properties and the orientation of the molecules. It was found that in multilayers as well as in mixed layers the CuPc molecules adopt the orientation of PTCDA molecules with the molecular plane parallel to the substrate. The multilayers were described using the anisotropic dielectric functions of the constituents including intermixing and roughness at the interfaces. The deviation between the simulation and the experiment suggests an electronic interaction due to coupling between the p-orbitals of CuPc and PTCDA at the interfaces. The simulation of the mixed layers reveals a change in line shape of the Q-band of CuPc. Beside ellipsometry and infrared spectroscopy techniques like x-ray reflectometry and AFM were used for investigations. Additionally in this diploma thesis a special sample holder and manipulator was designed with which in-situ-ellipsometry measurements in ultra high vacuum can be performed. / Im Rahmen dieser Diplomarbeit wurden die optischen Eigenschaften von organischen Multilayern und Mischschichten untersucht. Die Schichtstrukturen wurden im Hochvakuum nach dem Verfahren der organischen Molekularstrahldeposition (OMBD) auf H-passivierten Silizium(111)-Substraten hergestellt. Die optische Charakterisierung erfolgte mit dem Verfahren der spektroskopischen Ellipsometrie und der Infrarotspektroskopie. Dabei wurden zwei verschiedene Materialienpaarungen untersucht, die zum einen aus den organischen Substanzen Aluminium 8-Hydroxichinolat (Alq3) und N,N'-Di(1-naphthyl)-N,N'-diphenylbenzidin (a-NPD) und zum anderen aus Perylentetracarbonsäuredianhydrid (PTCDA) und Kupferphthalocyanin (CuPc) bestanden. Das optische Verhalten der Multilayer und der Mischschichten bestehend aus Alq3 und a-NPD konnte mit den isotropen dielektrischen Funktionen der Einzelschichten simuliert werden. In den PTCDA/CuPc-Schichtsystemen führt die planare Struktur der Moleküle zu einer starken Überlappung der p-Orbitale, was einen großen Einfluss auf die optischen Eigenschaften und die Orientierung der Moleküle hat. Es wurde festgestellt, dass sowohl in den Multilayern als auch in den Mischschichten die CuPc-Moleküle die Anordnung der PTCDA-Moleküle annehmen. Die Multilayer wurden unter Verwendung der anisotropen dielektrischen Funktionen der beteiligten Materialien und unter Berücksichtigung von Grenzflächenrauhigkeit simuliert. Die Unterschiede zwischen Experiment und Modell sind auf eine Kopplung zwischen den p-Orbitalen zurückzuführen. Die Simulationen der Mischschichten zeigten eine Veränderung der Linienform des Q-Bandes von CuPc. Als Untersuchungsmethoden kamen neben der Ellipsometrie und der Infrarotspektroskopie auch die Röntgen-Reflektometrie und das AFM zum Einsatz. Darüber hinaus wurde in dieser Arbeit eine Messeinrichtung aufgebaut, mit der in-situ-Ellipsometriecharakterisierung von Proben im Ultrahochvakuum möglich ist.

The principles of ancient Greek architecture have persevered through millennia, their impact ebbing and flowing perhaps, but still considered a fundamental layer on which Western architectural traditions have been built. Keeping in mind the pragmatic, aesthetic, and ideological influence Greek architecture has continued to have, my dissertation turns to contemporaneous sources to gauge the Greeks’ reception of their own sacred architecture. Scholars of Greek religion tend to agree that the temple was not a necessary component of ritual – boundary stones delineating sacred space and an altar on which communication with the divine was sought through sacrifice and non-sanguinary offerings were enough for religious rites. Why, then, were considerable effort and funds put towards the construction of temples, often monumental and virtually ubiquitous across the Greek landscape? Paradoxically, why is Greek literature, an art form that valued ekphrastic accounts of artworks (Homer’s description of the shield of Achilles [Iliad 18.478-608] is an oft-cited example) mostly silent on sacred architecture save for few laconic and formulaic appellations and rather dry descriptions (Greek traveler Pausanias, for instance, focused on sanctuary histories and votive offerings but was rather disinterested in architecture)? There appears to be a disparity between etic and emic perceptions of Greek sacred architecture, but, in fact, ancient evidence proves otherwise and demonstrates that artists were mindful of the potency of sacred structures. My dissertation pieces together their visual testimonies, particularly in vase painting which is arguably the most prolific and far-reaching medium of Greek art. Through an exhaustive perusal of museum collections, archives, and pottery-focused publications, the present study assembles a collection of nearly three-hundred vase paintings with depictions of sacred architecture and covering a time period of around three centuries from the Archaic period (seventh-century BCE) to the end of the Late Classical period (late fourth century BCE). The majority of the objects originate in Athens and its environs (Attika) and Magna Graecia. Based on this chronological and geographical scope, the study examines the images in four chapters: Attic black-figure vase paintings, Attic red-figure vase paintings with non-mythological subjects, Attic red-figure vase paintings with depictions of myth, and South Italian vase paintings. Within these chapters, the typology of architectural elements (e.g., freestanding columns, temple facades) and subject matter (e.g., myths, quotidian activities) constitute the primary criteria with which the images have been categorized. This extensive collection of vase paintings provides manifold insights into not only the reception of sacred architecture but also architectural elements as effective pictorial motifs. A great number of the depictions can be connected to “real” prototypes and, in some cases, distinct religious practices. While previous studies have taken a similar approach only to fixate on the discrepancies between prototypes and what architectural depictions can tell us about ancient building practices, the present study argues that vase painters rarely, if at all, intended to reproduce existing structures. Thus, the evidence should be used to study the ways in which artists reflected and refracted how buildings shaped and were shaped by the needs of their users. Creating an autonomous visual language built on abbreviation, elision, and synthesis, artists, in fact, rendered structures fit for the pictorial world. Their aim was not exactitude but rather verisimilitude – temples, shrines, portals, sanctuaries that were guided by but never unequivocally subservient to reality. The semiotic analysis of architecture, meanwhile, considers the aesthetics of vase painting and the objecthood of the vase. Beyond their face value (i.e., signifying sacred structures), elements like columns and simplified temples configure the surface of the vase into distinct zones, thus denoting spatio-temporal transitions, and hierarchize figures within the depicted events. Moreover, there are numerous instances where the pictorial frame is transformed into a built environment itself with the use of architecture – a practice that urges the viewer to contemplate the tension between the flatness of the ‘canvas’ and the habitable spaces defined by the juxtaposition of figures and structures.

Les processus de bioturbation constituent un exemple classique d’ingénierie de l’écosystème. Ils sont le fait d’espèces bioturbatrices qui contribuent à la structuration physique et biogéochimique des environnements sédimentaires. Dans les environnements marins meubles, les thalassinidés comptent parmi les bioturbateurs les plus influents. Ainsi, la crevette de vase Upogebia cf. pusilla est à l’origine d’un important remaniement sédimentaire et d’une large bioirrigation des sédiments dans le bassin d’Arcachon. Ces activités de bioturbation modulent les processus de minéralisation de la matière organique et les flux biogéochimiques à l’interface eau-sédiment. L’intensité de la bioturbation de U. cf. pusilla dépend de son état physiologique, celui-ci pouvant être altéré par divers facteurs de stress. Une approche couplant études de terrain et expérimentations en laboratoire a permis d’évaluer l’influence du parasitisme et de la contamination métallique sur les activités de U. cf. pusilla. Ce travail avait pour objectifs de (1) caractériser la pression parasitaire chez U. cf. pusilla à l’échelle locale, (2) déterminer les niveaux de base des éléments métalliques chez cet organisme dans le bassin d’Arcachon et d’évaluer le potentiel rôle des parasites dans les processus d’accumulation des métaux et (3) estimer l’impact du parasitisme et de la contamination métallique, seuls et en interaction, sur U. cf. pusilla et ce à deux échelles d’organisation, moléculaire et comportementale. In situ, un suivi spatial et un suivi temporel ont permis de caractériser la dynamique spatio-temporelle de deux parasites chez U. cf. pusilla¸ un bopyre infestant la cavité branchiale (Gyge branchialis), et un trématode (Maritrema sp.), infectant l’ensemble des organes de l’animal. Au sein de leur hôte, ces deux parasites sont négativement associés, le bopyre limitant probablement les processus d’infection par le trématode. Par ailleurs, un suivi saisonnier d’un an a permis de noter de faibles concentrations en métaux chez U. cf. pusilla, dans le bassin d’Arcachon. Ces concentrations ont été mises en parallèle avec le statut parasitaire des spécimens échantillonnés. Aucune corrélation n’a été notée entre la présence des trématodes et les quantités de métaux accumulées. A l’inverse, les observations de terrain ont permis d’envisager que le parasite bopyre puisse interférer avec les processus d’accumulation des métaux chez cet organisme. Cette dernière hypothèse a été testée en laboratoire au cours d’expérimentations visant à évaluer l’influence d’une contamination métallique (en utilisant le cadmium comme contaminant modèle) et du parasite bopyre, seuls et en interaction, sur U. cf. pusilla. A l’échelle moléculaire, le bopyre n’a été associé à aucune modification de l’expression d’une dizaine de gènes cibles. Par ailleurs, à l’échelle comportementale, ce parasite réduit peu le remaniement sédimentaire de son hôte, à l’inverse de ce qui avait été montré au cours d’une étude antérieure. En ce qui concerne l’influence du cadmium, ce métal module amplement l’expression de gènes codant notamment des protéines impliquées dans la réponse au stress oxydant et dans les mécanismes de détoxication. Ces observations suggèrent que U. cf. pusilla est capable de mettre en place des mécanismes de lutte contre le stress métallique. Au niveau comportemental, le cadmium semble stimuler le remaniement sédimentaire des organismes. Finalement, les expériences « doubles stress » ont montré un effet antagoniste du bopyre et du cadmium à la fois à l’échelle génique et à l’échelle comportementale. Ainsi, cette étude souligne la complexité des interactions entre facteurs de stress multiples et la nécessité d’effectuer de telles expérimentations. [...] / Bioturbation is a typical example of ecosystem engineering. Bioturbating species are mainly epi- or endobenthic organisms, which profoundly affect the physical structure and biogeochemical properties of sediments. In marine soft-bottom environments, thalassinidean mud shrimp are considered as one of the most prominent bioturbating organisms. Among these species is the mud shrimp Upogebia cf. pusilla, which is recognized as an important sediment reworker, also significantly contributing to the bioirrigation of sediments. In fine, this species greatly modulates organic matter mineralization and biogeochemical fluxes at the sediment-water interface. The influence of U. cf. pusilla in ecosystem functioning depends on the intensity of its bioturbation and thus on its fitness. Several factors can affect the physiological status of organisms, potentially resulting in behavioural changes and causing modifications of their activities. Amongst potential stressors, we evaluated the influence of parasitism and trace metal contamination on the mud shrimp U. cf. pusilla in Arcachon Bay, France. Field surveys and laboratory experiments were undertaken in order to evaluate (1) the parasite infestation levels in the mud shrimp at the local scale, (2) the metal contamination background and potential relationship between the metal accumulation and the parasitic status of organisms in the field and (3) estimate the distinct and interactive impacts of parasitism and metal contamination on two scales of organisation, by targeting a molecular (gene expression) and a behavioural (sediment reworking) endpoint.A large spatial and temporal survey conducted in Arcachon Bay showed that at least two parasites species occur in mud shrimp: a bopyrid isopod (Gyge branchialis), living in one of the gill chambers of its host, and a trematode parasite (Maritrema sp.), infecting the whole body of mud shrimp. These two parasite species are negatively associated within their host, in which the bopyrid likely interferes with trematodes establishment. Additionally, a one year seasonal sampling demonstrated that mud shrimp displayed very low levels of metals in Arcachon Bay. The bopyrid parasite could interfere with the process of metal accumulation in mud shrimp, while such correlation was not found for the trematode parasite. Finally, complementary laboratory experiments highlighted that, at the molecular level, the bopyrid parasite did not affect the expression of the genes targeted in this study in mud shrimp. Similarly, at the behavioural level, and conversely to a previous study, the effects of the bopyrid parasite were minor, i.e. only associated to small modifications of the bioturbation activity of its host. Indeed, the intensity of the sediment reworking of mud shrimp was slightly reduced when organisms were infested with this parasite. Regarding trace metal contamination, we noticed that mud shrimp largely accumulated cadmium. This accumulation was associated to an important modulation of gene expression, especially of genes encoding proteins involved in detoxification processes, highlighting, at this organisation level, the capability of mud shrimp to deal with the deleterious effect of cadmium. At the behavioural scale, cadmium contamination positively affected the sediment reworking activity of mud shrimp. Finally, double-stress experiments evidenced an antagonistic effect of both stressors on the two targeted endpoints. This study highlights the complexity of the interactions between multiple stressors and that the response of organisms cannot be predicted from “single-stress” experiments. [...]

Figures who turn their heads frontally and gaze outwards from Archaic Greek artworks look back at the viewer and destabilize the typical relationship between viewing subject and viewed object. These frontal characters were especially effective for viewers who encountered them during the Archaic period, when the profile perspective was conventional and vision was understood to be a tactile sense. Frontal-facing figures have often been interpreted as carrying protective power or having the ability to threaten the viewer with their attention. While some frontal figures are intimidating, frontality and the represented gazes it engenders do not provoke a single, universal reaction. Instead, these images’ interactions with ancient viewers were shaped by the type of frontal figure represented, the figure’s representational context, and the real context in which the figure was originally encountered. This dissertation takes a contextual approach to the study of Archaic frontal figures to arrive at a more nuanced understanding of their functions and effects. The frontal figures that are represented on vases made between 700 and 480 BCE are comprehensively examined. Frontal-facing characters that decorated temples in the same period are also considered. By inspecting each individual type of frontal figure in turn, we can better comprehend the differing responses the figures elicit, which include humor and horror in addition to terror. This project also examines how frontality was employed by innovative vase painters to create images that directly engage viewers and shape their viewing experiences. While a few figures were conventionally frontal in the Archaic period, the majority were represented frontally only by the most experimental artisans who were eager to surprise their viewers and distinguish their work from that of their colleagues. This investigation of Archaic frontality in multiple media demonstrates the power of the perspective in its original context and the inventiveness of the craftsmen who used it.

L’ébullition est un mode de transfert de chaleur intervenant dans de nombreux systèmes thermiques ou énergétiques de par son efficacité. Dans certains, elle se produit à basse pression. La pression statique induite par la colonne de liquide au-dessus de la surface de formation des bulles n’est alors pas négligeable devant la pression de saturation à la surface libre. Dès lors, la pression et le sous-refroidissement induit ne peuvent plus être considérés homogènes autour des bulles, d’où des inhomogénéités des propriétés thermophysiques dans le fluide. Les influences relatives des forces s’exerçant sur une bulle pendant sa croissance sont modifiées par rapport aux pressions plus élevées : une dynamique de bulles différente apparaît. Ces conditions particulières affectent également les transferts thermiques. L’influence de la pression sur l’ébullition en vase a été étudiée expérimentalement dans le régime de bulles isolées en site unique. L’eau a d’abord été testée sur une large gamme de pressions subatmosphériques. Quatre comportements de dynamique de bulles ont été identifiés d’après la visualisation par caméra rapide. Plusieurs paramètres de la dynamique ont été quantifiés grâce à un traitement d’images adapté appliqué aux vidéos. Pour généraliser le concept d’ébullition à « basse pression » et mieux en appréhender les phénomènes fondamentaux, de nouveaux essais ont été réalisés avec un second fluide, le cyclohexane, choisi pour sa similitude thermodynamique avec l’eau bouillant en deçà de la pression atmosphérique. La comparaison des comportements des deux fluides a permis d’identifier certains paramètres responsables des spécificités du phénomène. En outre, de nouvelles fonctionnalités sont apportées au dispositif expérimental pour – notamment – effectuer la mesure rapide du flux transféré sous la bulle pendant sa croissance, synchroniser ces mesures thermiques avec l’acquisition d’images et étudier des surfaces d’ébullition structurées. Les résultats obtenus sont encourageants pour l’analyse des comportements spécifiques de l’ébullition à basse pression et ses applications. / Boiling is an efficient heat transfer mode used in numerous thermal or energy systems. In some systems boiling takes place at low pressure. The static head of the liquid column over the wall where bubbles nucleate is then not negligible against the saturation pressure at the free surface level. The pressure and the induced subcooling degree therefore cannot be considered as homogeneous around growing bubbles, resulting in non-homogeneous thermophysical properties in the fluid. The relative influence of the forces acting on a growing bubble differs from higher pressure conditions, yielding specific bubble dynamics features. Heat transfer is consequently also affected. The effect of the pressure on pool boiling was experimentally investigated during the isolated bubbles regime taking place from a single activated nucleation site. Experiments were first conducted with water for a wide range of subatmospheric pressures. Four distinct bubble dynamics behaviors were identified through high-speed camera visualizations. An adapted image processing of the recordings enabled the measurement of several bubble dynamics characteristics. In order to generalize the concept of pool boiling at "low pressure" and to get a better understanding of the related fundamental phenomena, new experiments were performed with a second fluid, cyclohexane, chosen from original thermodynamic similarity with water boiling at pressures lower than atmospheric. The comparison of fluids’ behaviors made possible the identification of parameters governing the specific phenomena occurring during boiling at low pressure. Besides, the experimental facility was improved to provide new functionalities. The high-speed measurement of the heat flux transferred under the growing bubble, its synchronization with the high-speed videos images and the study of boiling on enhanced surfaces are in particular made possible. Results are encouraging for a better understanding of the specific behaviors of low pressure boiling and for its future implementation in practical applications.

Cette thèse se propose d’étudier l’expression du mouvement dans la peinture grecque ancienne, ici la peinture de vases, source très riche concernant l’univers visuel des Grecs de l’antiquité, et plus particulièrement le lien qui unit les émotions aux mouvements corporels. Les théories anciennes à propos de la représentation figurée sont unanimes : l’objet de la peinture est l’être humain et le peintre, dès les mythes qui relatent la création de la peinture et plus généralement des arts plastiques (sculpture et modelage), se doit de représenter le vivant sous tous ses aspects, extérieur comme intérieur; autrement dit, le corps humain apparaît comme le moyen le plus efficace pour exprimer et transmettre les émotions qui l’animent, par les mouvements ou les attitudes que le corps adopte ou encore les expressions faciales. Ce constat s’applique à l’expression des états émotionnels intenses ou altérés comme par exemple : les modifications qu’entraînent la consommation de vin, une action divine comme la possession par un dieu ou encore l’imminence de la mort. Il faut, pour mieux comprendre ces phénomènes, se tourner vers la conception ancienne de l’âme (θυμός et/ou ψυχή), qui dès l’époque homérique est conçue comme le siège des sentiments mais aussi comme un souffle qui entre et sort du corps. C’est une notion primordiale pour saisir la nature des mouvements qui animent les personnages figurés en proie à l’ivresse, sous le joug d’une possession divine ou sur le point de mourir : dans chacun de ces cas, l’âme est sollicitée d’une manière ou d’une autre, soit que ses liens avec le corps se trouvent relâchés ou qu’elle quitte temporairement ou définitivement le corps. Il apparaît que l’expression de ces états particuliers, dans l’imagerie grecque ancienne, n’ignore pas de tels concepts que ce soit à propos du but fixé à l’art ou sur la relation que l’âme entretient avec le corps : les mouvements corporels expriment clairement un état qui sort de l’ordinaire par l’orientation des corps, les gestes, les actions et les expressions faciales et ne semblent pas se borner à la figuration d’une simple réaction physiologique. Il s’agira également d’établir un lien entre les images anciennes et les théories modernes développées à propos de la figuration des mouvements dans l’art : le but étant de montrer que les peintres de vases privilégiaient bien plus l’expressivité, dans le but d’illustrer un concept, une idée, plutôt que de rendre compte d’une parfaite réalité / This thesis proposes to study the expression and depiction of movement in ancient Greek painting, specifically vase painting. While illustrating the very rich and unique source of the visual world of ancient Greece, the emphasis is kept on the link which unites the emotions to the body movements, gesture or posture. Theories about ancient pictorial representations are unanimous on the subject of painting the human figure. From the myths concerning the creation of painting and visual arts (sculpture & modeling), the artist must portray and illustrate the living in all aspects, external and internal. Using the human figure and representation of the anatomy, appears to be the most effective way to convey the emotions and feelings that animate the body through the depiction of gesture, posture or facial expression. This portrayal applies to the expression of intense emotion or altered state of being such as: the over consumption of wine, being possessed by a god (divine action) or the imminence of death. For a better understanding of the portrayal of this phenomenon, it is necessary to turn to the origin of the ancient Greek idea of the soul (θυμός or/and ψυχή). From the Homeric age this concept can be understood as the basis of sentiment and emotion and can be seen as natural as a breath which enters and exits the body. This notion is of key importance, to understand the origin of movement that brings to life the characters depicted in the images, whether consumed by drunkenness, under the yoke of divine possession or about to die. In each case, the soul is solicited, in one way or another, whether in its temporary or permanent separation or dissociative state from the body. Whether the aim is set out in art or in the relationship that the soul maintains with the body, Ancient Greek imagery does not ignore such concepts as the expression of these intense emotional and altered states whatsoever. Bodily movements clearly articulate an out of the ordinary state by the orientation of the body, gestures, actions and facial expressions and does not seem to be limited to the representation of only a physiological reaction. A link will be established between ancient images and modern theories developed on the subject of representation of movement in art. The objective: To demonstrate that the artists who adorned ancient vases favored the illustration of a concept or an idea, by imagination and expressivity, above the reporting of a perfect reality

La migration des bancs de vase observée le long des côtes Guyanaises génère des problématiques de navigation, particulièrement pour l'unique port de commerce de Guyane localisé dans l'estuaire du Mahury. La dynamique hydrosédimentaire de cet estuaire mésotidal et l'influence des bancs sur cette dernière sont très peu renseignées. Les principaux résultats de cette étude mettent en évidence l'importance relative du débit et des courants de marée sur la dynamique des sédiments fins. Bien que l'asymétrie de la marée soit dominée par le flot, les courants de jusant sont prédominants en saison humide et équivalents aux courants de flot en saison sèche. La dynamique des sédiments fins est gouvernée par la remise en suspension, bien que des épisodes de stratification puissent fortement atténuer la turbulence durant les premières heures du jusant. Les flux résiduels de sédiments sont généralement orientés vers l'amont durant la saison sèche et vers l'aval en saison humide, excepté lorsque les débits sont inférieurs aux moyennes saisonnières. L'évolution des fonds de l'estuaire sur 20 ans indique néanmoins une stabilité des dépôts et souligne la capacité de l'estuaire à évacuer les sédiments apportés durant la phase d'envasement. L'interdépendance entre l'estuaire du Mahury et le banc de Kaw sera ainsi soumise à discussion. Elle permettra d'évaluer la capacité du banc de Kaw à influencer la sédimentologie de l'estuaire et inversement d'évaluer la capacité de l'estuaire à perturber la migration du banc. / The mud banks migration observed along the Guyanese coastline generates navigating issues, especially for the unique harbor of French Guiana located in the Mahury Estuary. The hydro-sedimentary dynamic of this mesotidal estuary and the influence of the mud banks migration is poorly documented. The main results have brought to light the relative importance of the river discharge and tidal currents on the fine sediment dynamics. Even though the tidal asymmetry is dominated by the flood, the ebb currents are predominant during the wet season and are equivalent to the flood currents during the dry season. The fine sediment dynamics are mainly governed by the resuspension even though some stratification events can highly damp turbulence during the first hours of the ebb. The residual fluxes of sediment are generally landward during the dry season and in the wet season when river discharges are lower than the seasonnal averages. However, the bathymetric evolution over 20 years indicates the stability of the deposits and underlines the estuary's capacity of flushing sediments brought from the mud bank. The interdependence between the Mahury Estuary and the Kaw mudbank will therefore be subject to discussion. It will allow us to evaluate the mud bank influence on the estuarine sedimentology or, inversely, evaluate the capacity of the estuary to interfere with the mud bank migration and slowing down its progression with the currents.