Free vibrations of a thin elastic circular cylindrical panel localized near the rectilinear edge, propagating along the edge and decaying in its circumferential direction, are investigated in the framework of the two-dimensional equations in the Kircho↵-Love theory of shells. At first the panel is assumed to be infinite longitudinally and semi-infinite along its length of curvature (of course not realistically possible), followed by the assumption that the panel is then finite along its length of curvature and fixed and free conditions are imposed on the second resulting boundary. Using the comprehensive asymptotic analysis detailed in Kaplunov et al. (1998) “Dynamics of Thin Walled Elastic Bodies”, leading order asymptotic solutions are derived for three types of localized vibration, they are bending, extensional, and super-low frequency. Explicit representation of the exact solutions cannot be obtained due to the degree of complexity of the solving equations and relevant boundary conditions, however, computational methods are used to find exact numerical solutions and graphs. Parameters, particularly panel thickness, wavelength, poisson’s ratio, and circumferential panel length, are varied, and their e↵ects on vibration analyzed. This analysis is further extended to investigate localized vibration on the interface (perfect bond) of two cylindrical panels joined at their respective rectilinear edges, propagating along the interface and decaying in the circumferential direction away from the interface. An earlier, similar, localized vibration problem presented in Kaplunov et al. (1999) “Free Localized Vibrations of a Semi-Infinite Cylindrical Shell” and Kaplunov and Wilde (2002) “Free Interfacial Vibrations in Cylindrical Shells” is replicated for comparison with all cases. The asymptotics are similar, however in this problem the numerics highlight the stronger e↵ect of curvature on the decay of the super-low frequency vibrations, and to some extent on the leading order bending vibration.

The purpose of this study was to investigate strength and flexibility development as each is affected by three training programs using two apparatuss the Exer-Genie and the Super-Mini-Gym.

Ce travail de recherche est centré sur l’électromouillage sur diélectrique (EWOD) et l’emploi de surfaces superhydrophobes dans une optique d’intégration dans un système microfluidique en gouttes. Dans un premier temps, nous détaillons la réalisation de surfaces présentant différentes échelles de rugosités : micro-, nano- et micro/nanotexturées. Leur robustesse à l'imprégnation d'un liquide soumis à pression extérieure est étudiée. Deux techniques sont mises en œuvre, l’impact de goutte et l’EWOD. Les surfaces à double échelle de rugosité montrent une meilleure robustesse (>13kPa). Cependant, une surface de nanofils de silicium présente des seuils d’empalement à l’état de l’art (>17kPa) et une réversibilité complète sous EWOD. Dans un second temps nous caractérisons le déplacement de gouttes par EWOD au sein d’un système microfluidique et mettons en évidence l’influence des surfaces superhydrophobes (par rapport à des surfaces hydrophobes). Nous obtenons pour une tension donnée, des vitesses de déplacement supérieures (+30%), pour une vitesse donnée, une tension d’actuation réduite (-30%), ainsi que des contraintes de cisaillements proche paroi plus importantes. Enfin, ces propriétés sont mises en avant à travers deux applications que sont la collecte de bio-particules et l’analyse par spectrométrie de masse de biomolécules présentes en solution. Dans le premier cas, une efficacité de collecte proche de 100% est obtenue que ce soit pour des virus ou des spores. Dans le second cas, nous avons pu analyser des concentrations de peptides jusque 10fmol dans des zones localisées ainsi qu’un très faible niveau de pollution en dehors de ces zones. / This work deals with electrowetting on dielectric (EWOD) technique and integration of superhydrophobic surfaces in a droplet-based microfluidic device. The first part of the thesis consists on the preparation of micro-, nano- and micro-nano-structured surfaces, and a detailed study of their robustness to impalement under electrowetting and drop impact. Hierarchical surperhydrophobic surfaces showed the best robustness to impalement. However, a silicon nanowires surface has shown an impalement threshold still in the state of art with a total reversible behavior under EWOD. In a second approach, we characterized droplet displacement using electrowetting in a microfluidic system and evidenced the influence of superhydrophobic surfaces compared to hydrophobic ones. For a given actuation voltage, the droplet motion is increased by +30% and for a given droplet motion, the actuation voltage is reduced by -30%. Moreover, wall shear stresses are more important. Finally, these properties are featured through two main applications: particles collection and bio-molecules analysis by matrix-free laser desorption/ionization mass spectrometry. For particles collection, a cleaning efficiency close to 100% either for virus or bacteria particles was reached using superhydrophobic surfaces. For lab-on-chip application, a detection limit of 10 fmol was obtained for peptides analysis using mass spectrometry.

Magister Scientiae Dentium - MSc(Dent) / Introduction: Dental caries has one the highest incidences in children and the host’s diet may be a major factor in determining susceptibility to the disease. A proposed tool to screen and identify high risk individuals uses a bitter compound 6-n-propylthiouracil (PROP). The goal of this screening tool is to identify mothers and children who are Non-tasters (those who cannot taste PROP) and to educate them about their possible affinity towards sugar substances and its harmful effects on oral and general health. It is suggested that Non-taster children could be prioritized when providing preventative dental treatment. Aim: To validate the use of PROP as a screening tool for determining high caries risk individuals by identifying the taster status of mothers and children, their preference towards sugar, and its impact on their caries status. Methodology: 75 mother/ child pairs were recruited to participate in this study. Caries experience, sugar preference and taster status were determined for all the subjects. Comparisons were made between mothers and their children to find a possible association. Results: Caries experience was greater in individuals who were Non-tasters when compared to Super-tasters. A significant association between taster status and DMFT score was established (p<0.000). A significant association between taster status and sugar preference was established (p<0.000). A positive correlation with regard to taster status, sugar preference and caries experience was observed in mother/child pairs.

[pt] Apresentação da influência grega no pensamento de Nietzsche, que o leva a afirmar o mundo como estético e sua crítica à metafísica ocidental. A única possibilidade de conhecimento, para o autor, se dá através da arte, pois esta mostra o mundo em um processo constante de construção e destruição, através do fluxo e da rede de forças. O super-homem, grande novidade do pensamento nietzschiano, se mostra vinculado intrinsecamente ao surgimento do gênio, que é o grande criador de novos valores, capazes de libertar o homem da influência moral do pensamento metafísico. / [en] Presentation of the Greek’s influence on Nietzsche´s thought, that leads him to affirm the world as aesthetic and his critic to the occidental metaphysics. The only possibility to knowledge, for the author, takes place through art, which shows the world in a constant construction and destruction process through the flow and the network of forces. The superman, the greatest newness on Nietzsche´s thought, shows itself intrinsically entailed to the genius appearance, being the great creator of new values that will release mankind from the moral influence of metaphysics thought.

Aqui apresentamos um modelo teórico para superfícies super-hidrofóbicas que são formadas por superfícies contendo padrões periódicos na forma de microcavidades. Com este modelo obtivemos a relação ideal entre profundidade e diâmetro das cavidades para que a superfície manifeste seu caráter super-hidrofóbico. Assim, fabricamos superfícies em PDMS (popular silicone) capazes de produzir ângulos de contato elevados. Produzimos amostras contendo microcavidades específicas (paralelepípedas, hexagonais e cilíndricas) as quais foram microfabricadas por litografia de feixes de elétrons e caracterizadas por Microscopia Eletrônica de Varredura (MEV), Microscopia de Força Atômica (AFM), e medidas de ângulo de contato. Os padrões das microcavidades das superfícies produzidas seguiram as considerações da teoria e as medidas dos ângulos de contato de avanço e recesso mostram boa concordância com as previsões do modelo. Portanto, podemos afirmar que a teoria aqui descrita permite projetar superfícies altamente hidrofóbicas. / Here we present a theoretical model for super-hydrophobic surfaces formed by surfaces containing periodic patterns in the form of microcavities. With this model we obtained the ideal relationship between depth and diameter of the cavities so that the surface expresses a super-hydrophobic character. Thus manufacture of PDMS surfaces (with known silicone) is capable of producing high contact angles. We produced samples containing specific microcavities (parallelepipeds, hexagonal and cylindrical) which have been microfabricated by electron beam lithography and characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle measurements. The patterns of the surfaces of the cavities produced following the considerations of theory and measurements of advancing and recending contact angles show good agreement with the model predictions. Therefore, we can attest that the theory described here allows the design of highly hydrophobic surfaces.

Thesis (Ph.D.)--Boston University / This dissertation attempts to investigate the psychological nature of the conscience in Freudian theory and evaluate it in the light of certain neo-Freudian and non-Freudian findings. Special attention is given to the original work of Sigmund Freud and particular emphasis is placed on his concept of the super-ego, In psychological literature conscience is generally referred to as the super-ego. For Freud, the super-ego comes into being through the psychic processes of repression, identification and introjection. Its central task is that of playing the role within the personality once occupied by the parental or other authorities. The super-ego tends to accent the harshness, severity and restrictiveness of the parents far more than their love and kindness. Other Freudians, notably Bergler, Flugel, Klein and Jones expand Freud's early theories of conscience as a stern and punitive tendency in personality. They see the ideal self-image as of little value and rooted in unrealistic expectations [TRUNCATED]

Este trabalho buscou avaliar a técnica ultrassônica de Tempo de Voo da Onda Difratada (TOFD - Time-Of-Flight-Diffraction) para o monitoramento de trincas de fadiga nucleadas no interior de tubos de aço Superdúplex. Para isso, foram fabricados corpos de prova do tipo single edge bending SE(B) a partir de um tubo de aço Superdúplex sem costura. Estas amostras foram ensaiadas em fadiga, e o crescimento de trinca foi monitorado com as técnicas de TOFD, de Flexibilidade no Descarregamento (Compliance) – durante os ensaios, foram dadas sobrecargas mecânicas que causaram deformação plástica. As deformações serviram de pontos de referência para analisar o crescimento de trinca. Para aferir a validade os resultados obtidos com o TOFD nos ensaios de fadiga e fazer uma correlação com o monitoramento em campo de defeitos em tubos de aço Superdúplex, foi fabricado um padrão que simulou um tubo com defeito interno conhecido. Este padrão foi inspecionado com o TOFD, empregando os mesmos equipamentos e parâmetros utilizados nos ensaios de fadiga. Foi possível monitorar o crescimento de trinca em fadiga utilizando a técnica de TOFD e houve forte correlação entre os dados obtidos com o TOFD e o Compliance. A inspeção no tubo padrão manteve uma diferença entre a medida real e a obtida com o TOFD proporcional às encontradas durante o monitoramento dos ensaios de fadiga. / This study aimed to evaluate the ultrasonic technique Time-Of-Flight-Diffraction (TOFD) in monitoring fatigue nucleated cracks within super duplex steel pipes. In order to do it, single edge bending SE (B) specimens were manufactured using a super duplex steel seamless pipe. These samples were tested in fatigue and crack growth was monitored with two different techniques: TOFD and Flexibility in Unloading (Compliance). During the tests, it was used mechanical overloadings so deformation would be cause on the steel pipes. The deformations caused by that served as reference points to analyze the cracking growth. Thus, to assess the validity of the data obtained with the TOFD in fatigue tests, it was made a pattern that simulated a tube with known internal defect. This pattern was inspected with the TOFD, using the same equipment and parameters used in the fatigue tests. A correlation with the monitoring of defects field super duplex steel pipes was also made. The experiment has shown it is possible to monitor the cracking growth fatigue using the TOFD technique. Figures indicate, as well, there is a strong correlation between results obtained with the TOFD and Compliance. The inspection of the standard steel pipe maintained a difference between the actual measurement and obtained measurement. That difference was proportional from TOFD data and those found during the monitoring of the fatigue tests.

Magister Scientiae Dentium - MSc(Dent) / Introduction: Dental caries has one the highest incidences in children and the host’s diet may be a major factor in determining susceptibility to the disease. A proposed tool to screen and identify high risk individuals uses a bitter compound 6-n-propylthiouracil (PROP). The goal of this screening tool is to identify mothers and children who are Non-tasters (those who cannot taste PROP) and to educate them about their possible affinity towards sugar substances and its harmful effects on oral and general health. It is suggested that Non-taster children could be prioritized when providing preventative dental treatment. Aim: To validate the use of PROP as a screening tool for determining high caries risk individuals by identifying the taster status of mothers and children, their preference towards sugar, and its impact on their caries status. Methodology: 75 mother/ child pairs were recruited to participate in this study. Caries experience, sugar preference and taster status were determined for all the subjects. Comparisons were made between mothers and their children to find a possible association. Results: Caries experience was greater in individuals who were Non-tasters when compared to Super-tasters. A significant association between taster status and DMFT score was established (p<0.000). A significant association between taster status and sugar preference was established (p<0.000). A positive correlation with regard to taster status, sugar preference and caries experience was observed in mother/child pairs. Conclusion: Similarities in the mother's and child’s PROP taster status and its association with sugar preference allows such a screening test to identify individuals who are at high risk of developing dental caries. Early identification of mothers who are Non-tasters may allow the introduction of early intervention strategies and assist in the early detection of potentially high-risk children, especially in environments where resources are limited.

O objetivo principal deste projeto foi o estudo das propriedades ópticas de estruturas semicondutoras do tipo super-redes, formadas a partir da heteroestrutura de GaAs/AlAs, crescida através da técnica de Epitaxia por Feixe Molecular. No trabalho apresentamos estudos feitos em super-redes do tipo (GaAs)n/(AlAs)n, crescidas em substratos semi-isolantes e orientados nas direções (100) e (nl1) com n=1,2,3,5,7 e nas polaridades A e B. Para cada periodicidade (n x n), as estruturas foram crescidas simultaneamente num mesmo porta amostra e sob as mesmas condições. As amostras foram estudadas através das técnicas de fotoluminescência a baixa temperatura e em função da temperatura. São apresentados também resultados preliminares de um estudo feito com a técnica de fotoluminescência de excitação. A técnica de difração de elétrons de alta energia foi utilizada durante o crescimento epitaxial para aferição da periodicidade da estrutura. A eficiência quântica, a posição do pico de luminescência estão fortemente correlacionados com a direção de crescimento. As medidas de fotoluminescência em função da temperatura mostram também um decréscimo anômalo da largura de linha. A partir dos resultados ópticos foi proposta a formação de microestruturas de mais baixa diemnsionalidade nos poços, formadas por flutuações nas interfaces (microrugosidades), e originárias do modo de crescimento adotado (sem interrupção nas interfaces). O comportamento óptico observado é semelhante ao de estruturas de mais baixa dimensionalidade (pontos quânticos). Este efeito é acentuado nas direções (311) e (21l), devido a própria morfologia da superfície / The main objective of this work was the study of the optical properties of semiconductors superlattices, formed by the (GaAs)n,/(AlAs)n, heterostructure, and grown by technique of Molecular Beam Epitaxy. In the work, we presented studies in (GaAs)n/(AlAs)n, superlattices, grown on semi-insulating substrates oriented in planes (100) and (n11) with n=l, 2, 3, 5, 7 and in the polarities A and B. For each periodicity (n x n), the structures were simultaneously grown in a same sample holder, and under the same conditions. The samples were studied by the photoluminescence techniques at low temperature and in function of the temperature. Preliminares results of a study done with the technique of excitation photoluminescence are also presented. The technique of high energy eletron difraction was used during the epitaxial growth for the monitoring of the periodicity of the structure. The quantum efficiency and the positions of the luminescence peak are strongly correlated with the growth direction. The photoluminescence measures in function of the temperature also show an anomalous decrease in linewidth. The analyses of the optical results shown the possibility of low dimension microstructures formation in the wells, due to the interfaces fluctuations, and related with the growth mode (without interruption at the interface). The observed optical behavior is similar to the observed in the structures of lower dimensionality (quantum dots). This effect is accentuated in the plans (311) and (211), due to the morphology of the surface