O trajeto do canal da mandíbula é oblíquo com sentido póstero-anterior, apresenta-se próximo da cortical óssea alveolar medial, até atingir a face mesial do primeiro molar inferior, a partir desta região aproxima-se da lâmina óssea alveolar lateral até alcançar o forame mentual. Radiograficamente, o canal da mandíbula se apresenta, como uma linha radiolúcida delimitada por duas linhas radiopacas. Existem diversos métodos de exames radiográficos que possibilitem a avaliação do complexo maxilo-mandibular. Estudos mostram que a Tomografia Computadorizada (TC) foi considerado o melhor método para a avaliação do trajeto no sentido vestíbulo-lingual do canal da mandíbula. Foi proposto analisar a morfologia no sentido vestíbulo-lingual das variações do trajeto do canal da mandíbula em imagens de TC utilizando o software Dental Slice®. Com a ferramenta mensuração deste software , avaliou-se 100 TC bilateralmente, criando-se três retas. Uma horizontal (vestíbulo-lingual), dividindo o canal ao meio, e duas retas verticais, tangenciando a face externa lingual e vestibular da cortical do canal. Para análise dos dados utilizou os testes de normalidade, teste de hipótese (teste t e ANOVA) e teste de aderência Anderson Darling. Concluiu-se que existe uma tendência da presença de pouca variabilidade, entre os lados direito e esquerdo; a porção do canal mais próxima ao forame mentual apresenta-se vestibularizado, e na região posterior lingualizado; há necessidade da avaliação topográfica do canal da mandíbula por meio da Tomografia Computadorizada. / The course of the mandibles canal is oblique with posterior-anterior direction, it comes close to the medial cortical alveolar bony, until reaching the mesial face of the first inferior molar, starting from this area, it approaches of the lateral cortical alveolar bony until reaching the forame mentual. Radiographically, the manbible´s canal comes, as a radiolucent line defined by two radiopaque lines. Several methods of exams radiographyc that facilitate the evaluation of the complex maxilo-mandibular. Studies show that the Computerized Tomography (TC) is the best method for consider the evaluation of the course in the vestibule-lingual direction of the mandibles canal. It was intended to analyze the morphology in the vestibule-lingual direction of the variations of the course the mandibles canal in images of TC using the Dental Slice® software. With the mensuration tool of this software, 100 TC was evaluated bilaterally, being created three straight line. A horizontal one (vestibule-lingual), dividing the canal in the middle, and two vertical straight line, being tangent to the lingual external face and vestibular of the canals cortical. For analysis of the data it used the normality tests, hypothesis test (tests t and ANOVA) and test of adherence Anderson Darling. It conclude that a tendency exists the presence of little variability, among the sides right and left. The canal close to the forame mentual presents vestibular direction, and in the posterior area on lingual direction. And Confirm the need of the use of TC in the topographical evaluation of the mandibles canal.

A técnica da fotoelasticidade pode ser particularmente útil na análise de tensões em sistemas com geometrias complexas. Em um equipamento chamado polariscópio, um feixe de luz polarizada atravessa o modelo fotoelástico que representa o protótipo. Ao submeter este modelo a um carregamento, faixas de diferentes cores poderão ser visualizadas. Cada cor é associada a um nível de tensão. As tensões observadas no modelo fotoelástico podem ser comparadas com as tensões determinadas nos modelos numéricos ou analíticos. Em casos específicos, o problema da distribuição de tensões em uma fundação pode ser analisado com emprego da fotoelasticidade. A análise do comportamento de estacas helicoidais através da técnica da fotoelasticidade pode ser então de grande valia para estudos mais aprofundados deste sistema. O principal objetivo desta pesquisa foi viabilizar este método experimental para ser aplicado no Departamento de Geotecnia da EESC em análises de tensões em sistemas geotécnicos. Para validar as análises experimentais, tensões observadas em modelos de geometria simples foram comparadas com as tensões determinadas por meio de modelagem numérica com o método dos elementos finitos. O comportamento da fundação por estaca helicoidal observado pela técnica da fotoelasticidade mostrou semelhança ao observado na modelagem numérica. Por meio da distribuição de tensões, foi possível avaliar a influência da geometria helicoidal da lâmina e da profundidade de instalação da ancoragem no terreno. / The photoelastic method can be particularly useful for stress analysis with complex geometry systems. In equipment called polariscope, a polarized light beam crosses the photoelastic model that represents the prototype. Submitting this model to a load, fringes of different colors can be visualized. Each color is associated to a stress level. The stresses corresponding to the observed fringes on the photoelastic model can be compared to the stresses obtained through analytical or numerical models. In specific cases, the stress distribution problem can be analyzed with the use of photoelasticity. The photoelastic analysis of the helical pile behavior can then be valuable for further studies of this system. The main objective of this research was enabling this experimental method to be applied in the Department of Geotechnical Engineering of EESC in geotechnical systems stress analysis. To validate the experimental analysis, stresses observed in simple geometry models have been compared to those stresses determined by numerical modeling with the finite element method. The observed behavior of the helical pile foundation by photoelastic method showed similarity to that one observed through numerical modeling. Stress distribution analyses allowed evaluating the influence of helical blade geometry and the depth of installation.

Made available in DSpace on 2014-10-09T12:53:40Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:58:44Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Neste trabalho, desenvolveu-se um modelo matemático e um aparato de medidas, que têm como objetivo auxiliar no projeto e na caracterização de estruturas de ondas lentas para válvulas de ondas progressivas. O objetivo é obter as características de velocidade de fase e de impedância de interação de uma dada estrutura de ondas lentas. Modelou-se matematicamente uma estrutura de ondas lentas do tipo ringbar como uma hélice dupla contraposta, de forma que se obteve uma série de resultados teóricos já publicados e outros inéditos. Desenvolveu-se um aparato de medida em microondas para a caracterização experimental da estrutura de ondas lentas sob análise. Apresentam-se os procedimentos de medida e os resultados experimentais obtidos, comparando-os com as predições do modelo matemático. Os resultados experimentais apresentaram boa reprodutibilidade e distaram dos teóricos de acordo com o esperado. Considerou-se que o modelo matemático e o aparato de medida, bem como as técnicas experimentais, já constituem uma importante ferramenta que será de fundamental importância no projeto e fabricação de válvulas de ondas progressivas. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP / FAPESP:05/03612-0

As estacas helicoidais têm sido empregadas em diversos tipos de obras no Brasil e no mundo, principalmente em casos em que a fundação é submetida a carregamentos simultâneos de tração e de compressão ou que necessitam de rápida e facilitada instalação. O maior uso nacional é em fundações de torres de linhas de transmissão de energia, no entanto, são escassos os estudos do comportamento deste tipo de estaca em solos tropicais brasileiros. Considerando-se o crescimento do uso de estacas helicoidais no Brasil, e a necessidade de um melhor entendimento do comportamento deste tipo de fundação em nossos solos, o presente trabalho foi realizado para verificar a influência do arranjo das hélices, tanto do diâmetro quanto da quantidade, na capacidade de carga à tração das estacas helicoidais multi-hélices, instaladas em solo tropical da região de São Carlos, na cidade de Itirapina próxima a lagoa do Broa. A campanha de investigações geotécnicas foi composta por sondagens de simples reconhecimento (SPT) e ensaios de cone (CPT). Foram ensaiadas nove estacas, com diferentes configurações de diâmetro e de número de hélices, instaladas com a ponta em mesma profundidade, mesmo espaçamento entre hélices (igual a três vezes o maior diâmetro) e mesmo diâmetro de haste. Nesta investigação foram medidos os torques de instalação, e realizadas provas de cargas à tração do tipo estática com carregamento rápido. Como conclusões, o atrito lateral obtido com o ensaio CPT foi útil para verificar o efeito de perda de resistência do solo com a instalação da estaca; o método de capacidades de carga individuais obteve estimativas mais próximas as medidas em prova de carga; o efeito da configuração (cônicas ou cilíndricas) influencia no torque de instalação, mas não na capacidade de carga das estacas; o acréscimo de diâmetro médio das estacas é interessante para acréscimos na capacidade de carga, no entanto o acréscimo do número de hélices, a hélice superior sempre absorve menores cargas do que a hélice da ponta da estaca. / The helical piles have been used in different types of constructions, especially in cases where the foundation is subjected to tension and compression loads. In Brazil, this type of pile is normally used as the foundation of towers of power transmission lines, as guyed masts and self-supporting towers. However, there are few studies about the behavior of helical piles in Brazilian tropical soils. Considering the growing use of helical piles in Brazil, and the need of a better understanding of the behavior of this type of foundation in our soils, this study was conducted to evaluate the influence of the arrangement of the helices on the uplift capacity of helical piles installed in the tropical soil of São Carlos zone of São Paulo State. For this study, geotechnical investigations were carried out: standard penetration tests (SPT) and cone tests (CPT). Nine piles with different configurations (diameter and number of blades) were tested after being installed with the tip at the same final depth into the ground, and the same relative helix spacing (S/D>3). For this investigation, the torque necessary to install the piles were recorded, and subsequently static tensile loads tests were performed on all piles. As results: the lateral friction obtained with the CPT test was useful to check the effect of losing soil strength with the installation of the screw pile, the individual bearing method obtained estimates closer measurements in load test then cylindrical shear method; the effect of configuration (conical or cylindrical) influences on the torque installation, but not the uplift capacity of the screw piles, increases in the size of average diameter of helix in screw piles make increases in uplift capacity, however the increase in the number of helix did not appear as good as increases in the average diameter of the helix.

Doctor of Philosophy / Department of Chemistry / Christopher J. Levy / In the field of asymmetric catalysis salens and related molecules occupy a unique position in the breath and scope of reactions facilitated. They, nonetheless, are characterized by several conformationally derived limitations. This work deals with applying the principles of helicity with the goal of remedying these shortcomings, thereby ultimately fashioning, better, more selective catalysts. A series of novel ligands bearing phenanthryl and benz[a]anthryl side-arms attached to either a cyclohexyl or binaphthyl backbone bridging group, were prepared via multi-step synthesis. The ligands were subsequently metallated with zinc and iron salts to afford neutral helimeric complexes, that were characterized in the solution and solid states. The binaphthyl complexes were found via X-ray crystallographic analysis to afford exclusively M-helimers, while those incorporating a cyclohexyl bridge gave predominantly 1 : 1 P + M mixtures. A significantly greater degree of side-arm overlap was apparent where benz[a]anthryl side-arms were employed. 1H NMR analysis, unfortunately, did not allow for solution phase helimer determination, and ECD spectroscopy was therefore utilized as an alternative. In conjunction with computational techniques the conformations were probed, and to a high degree of certainty the prevailing solution geometries of the cyclohexyl complexes predicted. Our results indicate that in solution the M configuration is the sole or dominant form. Ionic zinc complexes based upon a tetradentate nitrogen donor motif and 8-isopropyl-2-quinolinecarboxaldehyde were also prepared. Structural characterization of the zinc complexes showed each to bind to two ZnCl2 units, and as a consequence to form dinuclear helicates.

There has been increasing concern regarding the emergence of multi-drug resistant pathogens. The resistance develops when pathogens, especially bacteria, are frequently exposed to conventional antibiotics, as they are heavily used in both human and livestock. This is due to the high target specificity of conventional antibiotics, which places pathogens in high selective pressures and eventually results in drug resistant by mutations. To address this issue, global actions and cooperation are needed. At the same time, new technologies and strategies need to be developed. Host defense peptides (HDPs) are widely found in the innate immune system. They show both direct antimicrobial properties and immunomodulatory activities. The multifaceted functions of HPDs make them less likely to promote antimicrobial resistance. Thus, they are promising as new therapeutics to treat multi-drug resistant infections. In fact, several drug candidates derived from HDPs have entered the clinical trial, but none of them got into the clinic. This is due to several challenges associated with HDPs, such as low in vivo stability, high cost of manufacturing, and toxicity to mammalian cells. In this dissertation, we explored the ability of a new type of unnatural scaffolds (γ-AApeptides) to mimic the functions of HDPs, including both broad spectrum antimicrobial properties and immunomodulatory activities. Furthermore, the efforts to identify simpler and more drug like γ-AApeptide based antimicrobial agents were also discussed. The findings in this dissertation may lead to the development of potential drug candidates to treat multi-drug resistant infections.

Lors de ce travail de thèse nous nous sommes intéressés à deux thèmes principaux dans le but de fabriquer des matériaux conducteurs chiraux : la synthèse de TTF-hélicènes présentant une chiralité hélicoïdale moléculaire, ainsi que l’obtention de molécules de symétrie 3 à base de TTF ayant la capacité à former des auto-assemblages supramoléculaires hélicoïdaux. Dans la partie TTF-hélicène, plusieurs tailles d’hélicènes ont été envisagées avec pour objectif d’obtenir des énantiomères stables et séparables. Ils ont été caractérisés par diffraction de rayons X, de même que les sels obtenus par électrocristallisation. De plus, une étude théorique de la réaction de photocyclisation des stilbènes en hélicènes a été menée pour comprendre sa régiosélectivité. Les molécules de symétrie 3 sont composées d’un coeur BTA-DABP sur lequel sont fixés des TTF avec leurs substituants chiraux. L’assemblage colonnaire des molécules est étudié par CD et les fibres formées sont observées par microscopie ce qui permet de déterminer leur hélicité. On varie le cœur ainsi que les groupements fixés dessus. / In this work, we have been interested in two different topics to make chiral conducting materials: the synthesis of TTF-helicenes, with molecular helical chirality, as well as the formation of three-fold symmetry molecules based on TTF units able to self-assemble into supramolecular helical aggregates. For the TTF-helicenes, several lengths of helicenes are considered in order to form stable and separable enantiomers. They are characterized by X-ray diffraction just as the salts that are obtained by electrocrystallization. Moreover, a theoretical study of the photocyclisation reaction of stilbenes into helicenes was performed to understand its regioselectivity. The three-fold symmetry molecules are composed of a BTA-DABP core on which TTF with chiral substituents are fixed. The assembly into columnar aggregates is followed by CD and the fibers formed are observed by microscopy in order to determine their helicity. Variation of the core and the substituents are made.

La conception de nouvelles molécules chirales est depuis plusieurs décennies un enjeu majeur. Ces travaux ont porté sur la synthèse ainsi que la caractérisation de diverses molécules à base d’hélicènes. En effet, les hélicènes sont chiraux et présentent des propriétés chiroptiques exceptionnelles. Ainsi, la combinaison de ces entités chirales associées à divers motifs permet la modulation de ces propriétés. Dans une première partie de ce manuscrit, nous nous sommes intéressés à l’association des hélicènes avec le motif tétrathiafulvalène (TTF) associant ainsi les propriétés redox du TTF à la chiralité des hélicènes. Une seconde partie concerne la préparation d’hélicènes luminescents à base de benzothiadiazole et de BODIPY avec pour objectif l’émission de lumière circulairement polarisée (CPL). Dans une troisième partie, nous avons étudié l’autoassemblage et la réactivité des motifs hélicéniques sur différentes surfaces de cuivre ou d’or. Enfin, nous avons réalisé des jonctions moléculaires à base d’hélicènes comme molécules uniques. En conclusion, nous avons développé différents motifs chiraux redox et photo-actifs ainsi que la formation de domaines auto-assemblés et des jonctions moléculaires à base d’hélicènes. / The development of new chiral molecules is a major challenge since few decades. This PhD work focuses on the synthesis and the characterisation of a variety of molecules based on helicenes. Indeed, helicenes are chiral and show exceptional chiroptical properties. Therefore, combining these chiral entities with various motifs allow the modulation of their properties. In a first part of this manuscript, we were interested in the association of helicenes with tetrathiafulvalene (TTF), thus combining the redox properties of TTF with the chirality of helicenes. The second part concerns the preparation of luminescent helicenes based on benzothiadiazole and BODIPY for circularly polarised light luminescence (CPL). In a third part we investigated the self-assembly and the reactivity of helicenes on gold and copper surfaces. Finally, we have prepared single molecule junctions based on helicenes. In Conclusion, we developed different redox and photoactive helicenes with applications towards the self-assembly on surfaces and single molecular junctions.

In recent years power generation from renewable energy has grown substantially both in South Africa and around the world. This growth is set to continue as there is more pressure to reduce the burning of fossil fuels. However, renewable energy power generation suffers from unpredictability, which causes problems when it comes to managing power grids. Concentrated Solar Power (CSP) plants offer a practical solution to store power in the form of thermal energy storage (TES). Thus, the plant can run when there is no solar energy available, leading to a more stable power supply. Unfortunately, CSP plants cost more than other renewables such as photovoltaic and wind power. Thus, there is a need for research into how to bring down the cost of CSP plants. One of the most proven types of CSP is the parabolic trough plant. The most recent innovation is to try and use molten salt as the heat transfer fluid which would reduce the cost of the plant. However, this new technology has not been implemented on a full scale CSP plant and little testing has been done to prove the technology. The HPS2 is a test facility aimed at testing the use of molten salt as a heat transfer fluid (HTF). This test facility, located in Evora Portugal, is being developed by an international consortium led by the German DLR institute of Solar Research. It is one of the first test facilities of its kind where experiments will be conducted to demonstrate the validity of using molten salt as a HTF and a storage medium in a parabolic trough CSP plant. The HPS2 test facility is not yet operational and there is a need for a dynamic thermofluid process model to better understand and predict both its steady state and transient operational behaviour. This dissertation reports on the development of such a dynamic thermofluid process model and the results obtained from it. The process model developed primarily focuses on the steam cycle with the TES incorporated into the model. The physical geometry of each of the components are employed to construct discretized elements for which the conservation of mass, energy, and momentum are applied in a one-dimensional network approach. The economizer and evaporator combined has a helical coil geometry and uses molten salt as a heat transfer fluid, which is unique. Thus, correlations had to be adjusted for the flow characteristics found in the economizer/evaporator. Results from the steady state simulations of the steam cycle show that the molten salt mass flowrate through the steam generation system will have to be reduced from the initially expected value to meet operational requirements. Results of the dynamic simulations show that the test facility will be able to produce a constant power supply despite transient solar conditions and highlights key dynamic responses for operators to be aware of.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第22272号 / 理博第4586号 / 新制||理||1658(附属図書館) / 京都大学大学院理学研究科化学専攻 / (主査)教授 大須賀 篤弘, 教授 依光 英樹, 教授 時任 宣博 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM