Cette thèse porte sur le traitement mathématique du problème de Hele-Shaw dans l’approximation de Stokes-Leibenson. À l’aide d’une transformation de type Helmholtz- Kirchhoff, nous explicitons une équation d’évolution du contour fluide valable pour tout type d’écoulement plan. Cette équation généralise des résultats précédents et permet alors d’établir un schéma numérique performant dit du quasi-contour, qui se réduit à un problème de Cauchy. Nous considérons ensuite l’étude du problème par transformations conformes menant à l’équation de Polubarinova-Galin. Dans le cas simple d’un contour représenté par un trinôme à coefficients réels, nous réussissons à expliciter la solution exacte du problème. Notons que les trajectoires des solutions exactes permettent de préciser la position de la frontière des domaines d’univalence décrits par les trinômes. Enfin, nous introduisons des paramètres de contrôle sous forme de coefficients d’un multipôle superposé à la source. Des conditions suffisantes de contrôlabilité sont établies et des résultats de contrôle optimal sont explicités pour les solutions binomiales et trinomiales. L’introduction de paramètres de contrôle permet de comprendre le lien qui relie les moments de Richardson à l’équation de Polubarinova-Galin. / This PhD thesis deals with the mathematical treatment of the Hele–Shaw problem in the Stokes–Leibenson approximation. By an Helmholtz–Kirchhoff transformation, we exhibited an evolutive equation of the fluid contour applicable to all type of planar fows. This equation generalizes previous results and also allows to state an efficient numerical scheme called quasi-contour’s, which is a simple Cauchy problem. We then consider the study of this problem using conformal transformations leading to the Polubarinova-Galin equation. In the simple case of a contour representing by a trinomial with real coefficients, we succeeded in exhibiting the exact solution of the problem. Notice that the trajectories of the exact solutions enable to precise the position of frontiers of univalent domains described by trinomials. Finally, we introduce control parameters under the form of coefficients of a multipole superposed to the source. Sufficient conditions of controllability are stated and results on optimal control established for the binomial and trinomial cases. Introduction of control parameters allows us to understand the link, which bound Richardson’s moments to the Polubarinova-Galin equation.

ix, 288 p. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / While the impact of Darwin's theory of evolution on Victorian and modernist literature has been well-documented, very little critical attention has been paid to the influence of Lamarckian evolutionary theory on literary portrayals of human progress during this same period. Lamarck's theory of inherited acquired characteristics provided an attractive alternative to the mechanism and materialism of Darwin's theory of natural selection for many writers in the late-nineteenth and early-twentieth centuries, particularly those who refused to relinquish the role of the individual will in the evolutionary process. Lamarckian rhetoric permeated an ideologically diverse range of discourses related to progress, including reproduction, degeneration, race, class, eugenics, education, and even art. By analyzing the literary texts of Olive Schreiner, G.B. Shaw, and W.B. Yeats alongside their polemical writing, I demonstrate how Lamarckism inflected these writers' perceptions of the mechanism of human evolution and their ideas about human progress, and I argue that their work helped to sustain Lamarck's cultural influence beyond his scientific relevance. In the dissertation's introduction, I place the work of these three writers in the context of the Neo-Darwinian and Neo-Lamarckian evolutionary debates in order to establish the scientific credibility and cultural attractiveness of Lamarckism during this period. Chapter II argues that Schreiner creates her own evolutionary theory that rejects the cold, competitive materialism inherent in Darwinism and builds upon Lamarck's mechanism, modifying Lamarckism to include a uniquely feminist emphasis on the importance of community, motherhood, and self-sacrifice for the betterment of the human race. In Chapter III, I demonstrate that Shaw's "metabiological" religion of Creative Evolution, as portrayed in Man and Superman and Back to Methuselah , is not simply Bergsonian vitalism repackaged as a Neo-Lamarckian evolutionary theory but, rather, a uniquely Shavian theory of human progress that combines religious, philosophical, and political elements and is thoroughly steeped in contemporary evolutionary science. Finally, Chapter IV examines the interplay between Yeats's aesthetics and his anxieties about class in both his poetry and his 1939 essay collection On the Boiler to show how Lamarckian modes of thought inflected his understanding of degeneration and reproduction and eventually led him to embrace eugenics. / Committee in charge: Paul Peppis, Chairperson, English; Mark Quigley, Member, English; Paul Farber, Member, Not from U of O; Richard Stein, Member, English; John McCole, Outside Member, History

Made available in DSpace on 2014-12-17T14:16:33Z (GMT). No. of bitstreams: 1 EvertonNA_DISSERT.pdf: 1792705 bytes, checksum: 2091882fa52265fca623e2d01c142cfa (MD5) Previous issue date: 2013-06-10 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Natural oils have shown a scientific importance due to its pharmacological activity and renewable character. The copaiba (Copaifera langsdorffii) and Bullfrog (Rana catesbeiana Shaw) oils are used in folk medicine particularly because the anti-inflammatory and antimicrobial activities. Emulsion could be eligible systems to improve the palatability and fragrance, enhance the pharmacological activities and reduce the toxicological effects of these oils. The aim of this work was to investigate the antimicrobial activity of emulsions based on copaiba (resin-oil and essential-oil) and bullfrog oils against fungi and bacteria which cause skin diseases. Firstly, the essential oil was extracted from copaiba oil-resin and the oils were characterized by gas chromatography coupled to a mass spectrometry (GC-MS). Secondly, emulsion systems were produced. A microbiological screening test with all products was performed followed (the minimum inhibitory concentration, the bioautography method and the antibiofilm determination). Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa, Candida albicans, C. parapsilosis, C. glabrata, C. krusei and C. tropicalis American Type Culture Collection (ATCC) and clinical samples were used. The emulsions based on copaiba oil-resin and essential oil improved the antimicrobial activity of the pure oils, especially against Staphylococcus e Candida resistant to azoles. The bullfrog oil emulsion and the pure bullfrog oil showed a lower effect on the microorganisms when compared to the copaiba samples. All the emulsions showed a significant antibiofilm activity by inhibiting the cell adhesion. Thus, it may be concluded that emulsions based on copaiba and bullfrog oils are promising candidates to treatment of fungal and bacterial skin infections / Os ?leos naturais v?m chamando aten??o da comunidade cient?fica devido a suas atividades farmacol?gicas e seu car?ter renov?vel. Os ?leos de copa?ba (Copaifera langsdorffii) e de r?-touro (Rana catesbeiana Shaw) ganham destaque, especialmente devido a ampla utiliza??o na medicina popular como anti-inflamat?rios e antimicrobianos. Sistemas emulsionados a base destes ?leos podem ser produzidos com a finalidade de melhorar o odor e a palatabilidade dos mesmos, al?m de potencializar a??o e reduzir toxicidade dos seus componentes. O objetivo deste trabalho foi investigar a atividade antimicrobiana de emuls?es contendo ?leos de copa?ba (?leo-resina e ?leo essencial) e ?leo de r?-touro frente a cepas de micro-organismos causadores de infec??es cut?neas. Inicialmente, foi realizada a extra??o de ?leo essencial e sua caracteriza??o qu?mica por cromatografia gasosa acoplada a espectroscopia de massas. Em seguida, foram produzidas emuls?es, ensaios de triagem microbiol?gica, microdilui??o para determina??o de concentra??o inibit?ria m?nima, bioautografia para determina??o dos componentes antimicrobianos e avalia??o da atividade antibiofilme. Foram utilizadas cepas da American Type Culture Collection (ATCC) e cl?nicas de Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa, Candida albicans, C. parapsilosis, C. glabrata, C. krusei e C. tropicalis. Foi observado que os sistemas emulsionados de ?leo-resina de copa?ba e ?leo essencial de copa?ba contribu?ram na potencializa??o da atividade antimicrobiana, especialmente contra cepas do g?nero Staphylococcus e Candida resistentes aos az?is. A emuls?o de ?leo de r?-touro assim como o ?leo puro, apresentou menor atividade que as amostras de copa?ba, por?m exibiu significativa a??o antibiofilme, demonstrando que este sistema ? um potencial inibidor da ades?o de micro-organismos. Deste modo, pode-se inferir que as emuls?es a base destes ?leos s?o promissores sistemas para o tratamento de infec??es cut?neas f?ngicas e bacterianas

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-06-29T13:52:59Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) tese_final.pdf: 5635071 bytes, checksum: b300efb627e9ece412ad5936ab67e8e2 (MD5) / Made available in DSpace on 2016-06-29T13:52:59Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) tese_final.pdf: 5635071 bytes, checksum: b300efb627e9ece412ad5936ab67e8e2 (MD5) Previous issue date: 2013-08-26 / CNPq / No presente trabalho duas classes de problemas são abordadas. Primeiramente, são apresentados estudos computacionais sobre o modelo O(n) de spins na rede quadrada, e em seguida apresentamos novas soluções exatas para a dinâmica de bolhas na célula de Hele-Shaw. O estudo do modelo O(n) é feito utilizando sua representação em laços (cadeias fechadas), a qual é obtida a partir de uma expansão para altas temperaturas. Nesse representação, a função de partição do modelo possui uma expansão diagramática em que cada termo depende do número e comprimento total de laços e do número de (auto)interseções entre esses laços. Propriedades críticas do modelo de laços O(n) são obtidas através de conceitos oriundos da teoria de percolação. Para executar as simulações Monte Carlo, usamos o eficiente algoritmo WORM, o qual realiza atualizações locais através do movimento da extremidade de uma cadeia aberta denominada de verme e não sofre com o problema de "critical slowing down". Para implementar esse algoritmo de forma eficiente para o modelo O(n) na rede quadrada, fazemos uso de um nova estrutura de dados conhecida como listas satélites. Apresentamos estimativas para o ponto crítico do modelo para vários valores de n no intervalo de 0 < n ≤ 2. Usamos as estatísticas de laços e vermes para extrair, respectivamente, os expoentes críticos térmicos e magnéticos do modelo. No estudo de dinâmica de interfaces, apresentamos uma solução exata bastante geral para um arranjo periódico de bolhas movendo-se com velocidade constante ao longo de uma célula de Hele-Shaw. Usando a periodicidade da solução, o domínio relevante do problema pode ser reduzido a uma célula unitária que contém uma única bolha. Nenhuma imposição de simetria sobre forma da bolha é feita, de modo que a solução é capaz de produzir bolhas completamente assimétricas. Nossa solução é obtida por métodos de transformações conformes entre domínios duplamente conexos, onde utilizamos a transformação de Schwarz-Christoffel generalizada para essa classe de domínios. / In this thesis two classes of problems are discussed. First, we present computational studies of the O(n) spin model on the square lattice and determine its critical properties, whereas in the second part of the thesis we present new exact solutions for bubble dynamics in a Hele-Shaw cell. The O(n) model is investigated by using its loop representation which is obtained from a high-temperature expansion of the original model. In this representation, the partition function admits an diagrammatic expansion in which each term depends on the number and total length of loops (closed graphs) as well as on the number of intersections between these loops. Critical properties of the O(n) model are obtained by employing concepts from percolation theory. To perform Monte Carlo simulations of the model, we use the WORM algorithm, which is an efficient algorithm that performs local updates through the motion of one of the ends (called head) of an open chain (called worm) and hence does not suffer from “critical slowing down”. To implement this algorithm efficiently for the O(n) model on the square lattice, we make use of a new data structure known as a satellite list. We present estimates for the critical point of the model for various values of n in the range 0 < n ≤ 2. We use the statistics about the loops and the worm to extract the thermal and magnetic critical exponents of the model, respectively. In our study about interface dynamics, we present a rather general exact solution for a periodic array of bubbles moving with constant velocity in a Hele-Shaw cell. Using the periodicity of the solution, the relevant domain of the problem can be reduced to a unit cell containing a single bubble. No symmetry requirement is imposed on the bubble shape, so that the solution is capable of generating completely asymmetrical bubbles. Our solution is obtained by using conformal mappings between doubly-connected domains and employing the generalized Schwarz-Christoffel formula for this class of domains.

La dispersion de particules par une onde de souffle ou de choc induit la formation de structures régulières qui prennent la forme de jets de particules. Jusqu'à présent, les expériences n'ont été réalisées qu'en trois dimensions rendant difficile l'exploitation des données. Dans cette étude, une onde de souffle, générée à l'extrémité d'un tube à choc, débouche au centre d'un anneau de particules solides initialement confiné dans une cellule de Hele-Shaw. Pour la première fois, à partir d'une expérience de laboratoire, la formation de jets de particules est observée dans une configuration quasi bi-dimensionnelle et pour de faibles niveaux de pression. Grâce à un système de visualisation ultra-rapide, il a été mis en évidence que la sélection du nombre de jets de particules est un processus instationnaire. Nous avons observé que les jets de particules sont initialement formés à l'intérieur de l'anneau et sont ensuite expulsés à l'extérieur du front de particules en expansion. L'influence de nombreux paramètres, tels que la densité et le diamètre des particules, la surpression générée et la géométrie de l'anneau, ont été étudiées. La synthèse des résultats expérimentaux obtenus a permis d'établir certaines relations empiriques reliant le nombre de jets aux propriétés initiales. De plus, la formation de fines perturbations sur le front externe de la couche de particules a été observée. Ce phénomène est quant à lui indépendant des jets principaux et dépend seulement de la nature des particules. / The dispersion of particles by a blast or a shock wave induces the formation of coherent structures which take the form of particle jets. All the experiments conducted so far have been performed in three-dimensional geometry. In the present study, a blast wave, issuing from the discharge of a planar shock wave at the exit of a conventional shock tube, is generated in the center of a granular medium ring initially confined inside a Hele-Shaw cell. With the present experimental set-up, under impulsive acceleration, a solid particle jet formation is clearly obtained and observed in a quasi-two-dimensional configuration, for the first time. From fast flow visualizations, we highlighted that the selection of the number of jets is unsteady. We noticed, in all instances, that the jets are initially generated inside the particle ring and thereafter expelled outward. This point has not been observed in three-dimensional experiments. The influence of many parameters such as density and diameter of particles, the generated pressure and the geometry of the ring, has been studied. Empirical relationships were deduced from the experimental curves. Moreover, we observed in detail the formation of very thin perturbations created around the external surface of the dispersed particle layer. This phenomenon is independent of the main jet formation and solely depends on the nature of particles.

Artie Shaw's Interlude in B-flat is unknown to many in the classical clarinet world and remains unperformed by clarinetists, despite its historical importance as one of the earliest Third Stream compositions, the earliest composition of its type in the clarinet repertoire. This prompts the question, why? This document explores four possible reasons for the marginalization of Interlude in B-flat. First, Shaw's historical narrative typically places him within the jazz world and not the classical world. Classical clarinetists may assume a Shaw composition will require a jazz background and experience beyond their abilities, namely improvisation. Second, the instrumentation, string quartet plus jazz combo, is atypical, making it difficult to program. Third, jazz and classical educational worlds do not necessarily overlap or interact, and neither has taken ownership of this Third Stream composition. Lastly, manuscripts, recordings, and other materials for Interlude in B-flat are limited and not readily available. Because Artie Shaw is not only a significant American clarinetist but also an important composer within the Third Stream narrative, Interlude in B-flat should be known and performed. This project aimed to promote the understanding and accessibility of this important and unknown composition to the classical clarinet world by providing an accessible arrangement of the work for clarinet and piano.

No description available.

By the beginning of the twentieth century, Ireland's identity was continually pulled between its loyalties to Catholicism and British imperialism. In response to this conflict of identity, W. B. Yeats and Lady Augusta Gregory argued the need for an Irish theatre that was demonstrative of the Irish people, returning to the literary traditions to the Celtic heritage. What resulted was a questioning of religion and politics in Ireland, specifically the Catholic Church and its priests. Yeat's own drama removed the priests from the stage and replaced them with characters demonstrative of those literary traditions, establishing what he called a "new priesthood". In response to this removal, Yeat's contemporaries such as J. M. Synge and Bernard Shaw evolved his vision, creating a criticism and, ultimately, a rejection of Irish priests. In doing so, these playwrights created depictions of absent, ineffectual, and pagan priests that have endured throughout the twentieth century.

Classical violin concertos by English composers are relatively obscure nowadays, as the genre is largely monopolized by Mozart’s last three concertos. This study explores the compositional and violinistic traits of ten English concertos from the late eighteenth century, as well as the social and cultural circumstances under which they were written. These concertos are challenging violinistically, suggesting that they were primarily intended as virtuosic showpieces. In addition, a number of the concertos display musical eccentricities that hint at the quirky personalities of their composers. In some respects, these concertos are unadventurous, particularly in terms of harmony and thematic contrasts. However, they contain a number of unique compositional features that are worthy of our attention. The most notable of these is the incorporation of Baroque features in a large number of the concertos, despite their general adherence to the new galant style. All evidence suggests that the two styles were combined deliberately as a compositional technique, and this is perhaps the most distinctly “English” characteristic of these concertos.

The process of fluid injection into granular media is relevant to a wide number of applications such as enhanced oil recovery, grouting, and the construction of permeable reactive barriers. The response of the subsurface is dependent on multiple factors such as in-situ stresses, fluid properties, flow rate, and formation type. Based on these conditions a variety of response mechanisms can be initiated ranging from simple porous infiltration to hydraulic fracturing. Currently, the mechanics of fluid injection into competent rock are well understood and can be sufficiently modeled using linear elastic fracture mechanics. Because the grains in rock formations are individually cemented together, they exhibit cohesion and are able to support tensile stresses. The linear elastic method assumes tensile failure due to stress concentrations at the fracture tip. A fracture propagates when the stress intensity factor exceeds the material toughness (Detournay, 1988) However, understanding fluid injection in cohesionless granular media presents a much larger obstacle. Currently, no theoretical models have been developed to deal with granular media displacements due to fluid injection. Difficulty arises from the complexity of fluid rheology and composition used in engineering processes, the strong coupling between fluid flow and mechanical deformation, the non-linear response of subsurface media, and the multi-scale nature of the problem. The structure of this thesis is intended to first give the reader a basic background of some of the fundamental concepts for non-Newtonian fluid flow in granular media. Fluid properties as well as some interaction mechanisms are described in relation to the injection process. Next, the results from an experimental series of injection tests are presented with a discussion of the failure/flow processes taking place. We developed a novel technique which allows us to visualize the injection process by use of a transparent Hele-Shaw cell. Specifically, we will be using polyacrylamide solutions at a variety of concentrations to study non-Newtonian effects on the response within the Hele-Shaw cell. By performing tests at a range of solution concentrations and injection rates we are to be able to identify a transition from an infiltration dominated flow regime to a fracturing dominated regime.