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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Dinâmica de homeomorfismos homotópicos à Dehn twists / On the dynamics of homeomorphisms of the torus homotopic to Dehn twists.

Bráulio Augusto Garcia 02 February 2012 (has links)
No presente trabalho apresentamos um estudo sobre a dinâmica de homeomorfismos do toro homotópicos à Dehn twists. No caso conservativo, provamos que se $f$ preserva área e tem um levantamento $\\hat$ para o cilindro com fluxo zero, então, precisamente, ou $f$ é um homeomorfismo do anel, ou possui pontos no cilindro com velocidades verticais positiva e negativa, por iteradas de $\\hat$. Isso resolve a conjectura de Boyland para essa classe de homotopia. Já no caso geral, mostramos um resultado análogo. Além disso, fornecemos uma condição extremamente simples que, quando satisfeita, implica que o conjunto de rotação vertical contém um intervalo e, portanto, que $f$ tem entropia topológica positiva. / The present thesis is concerned with the dynamics of homeomorphisms of the torus homotopic to Dehn twists. We prove that if $f$ is area preserving and it has a lift $\\hat$ to the cylinder with zero flux, then either $f$ is an annulus homeomorphism, or there are points in the cylinder with positive vertical velocity and others with negative vertical velocity, for iterates of $\\hat$. This solves a version of Boyland\'s conjecture to this setting. We extend some theorems we already obtained for Dehn twists with the area preservation hypothesis to a more general class. Finally, we also give a simple explicit condition which, when satisfied, implies that the vertical rotation set contains an interval and thus also implies positive topological entropy.
32

Avaliação da espessura dos músculos mastigatórios e da força de mordida molar máxima em indivíduos portadores de toro mandibular / Evaluation of the masticatory muscles thickness and the maximum molar bite force in subjects with mandibular torus

Pires, Cassia Perola dos Anjos Braga 06 August 2014 (has links)
O sistema estomatognático identifica um conjunto de estruturas bucais que desenvolvem funções comuns, tendo como característica constante a participação da mandíbula. Como todo sistema, tem características que lhe são próprias, mas depende do funcionamento, ou está intimamente ligado à função de outros sistemas como o nervoso, o circulatório e o endócrino. Tanto nos estados de saúde como nos de enfermidade, o sistema estomatognático pode influir sobre o funcionamento de outros sistemas como o digestório, respiratório e o metabólico-endócrino. Várias são as doenças e eventos clínicos que podem acometer o sistema estomatognático, acarretando o seu desequilíbrio ou mau funcionamento. Este estudo teve como objetivo analisar a espessura muscular e a força de mordida em 20 indivíduos diagnosticados com toro mandibular (Grupo Casos) e em 20 indivíduos sem toro (Grupo Controles). Para a análise ultrassonográfica foi utilizado o ultrassom portátil da marca NanoMaxx, com um transdutor linear - L 25 - de 06 a 13 MHz e 23 mm. Foram adquiridas três imagens ultrassonográficas dos músculos masseter e temporal, de ambos os lados, na posição de repouso e de contração voluntária máxima. Os registros da força de mordida foram realizados utilizando o dinamômetro digital, modelo IDDK (Kratos). As avaliações foram feitas nas regiões do primeiro molar (direito e esquerdo). Verificou-se que, os indivíduos portadores de toro na mandíbula apresentaram espessura dos músculos temporais significantemente menores que a dos indivíduos do Grupo Controles, enquanto que, os resultados para a força de mordida máxima foram significativamente maiores para os indivíduos do Grupo Casos e que não ocorreram correlações entre as espessuras e a força de mordida. Concluiu-se que a presença de toro mandibular promoveu alterações no sistema estomatognático. / The stomatognathic system has a set of oral structures that develop common functions, having as a constant share of the jaw. Like any system, it has characteristics of its own, but depends on the functioning, or is closely linked to the function of other systems such as the nervous, circulatory and endocrine. Both the states of health and illness in the stomatognathic system can influence the operation of other systems such as the digestive, respiratory and metabolic - endocrine. There are many diseases and clinical events that may affect the stomatognathic system, causing your imbalance or dysfunction. This study aimed to analyze the muscle thickness and bite force in 20 individuals diagnosed with mandibular torus (Cases Group) and 20 individuals without torus (Controls Group). For the analysis we used the ultrasound portable NanoMaxx, with a linear transducer - L 25 - 06-13 MHz and 23 mm. Three ultrasound images were acquired from masseter and temporalis muscles on both sides, at rest and maximal voluntary contraction. The records of bite force were performed using the digital dynamometer, IDDK model (Kratos). The assessments were made in the regions of the first molar (right and left). It was found that individuals with mandibular torus showed temporalis muscles thickness significantly lower than Controls Group subjects, whereas the results for the maximum bite force were significantly higher for Cases Group subjects, and there were no correlations between the thicknesses and the bite force. It was concluded that the presence of mandibular torus promoted changes in the stomatognathic system.
33

HipersuperfÃcies completas com k-Ãsima funÃÃo simÃtrica nula na esfera unitÃria.

Fabricio de Figueredo Oliveira 27 February 2008 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Neste trabalho vamos estudar hipersuperfÃcies M^n da esfera unitÃria S^{n+1} conexas completas com duas curvaturas principais distintas uma das quais de multiplicidade n-1 e possuindo k-Ãsima funÃÃo de curvatura nula Sob tais condiÃÃes vamos provar que o toro de Clifford à a Ãnica hipersuperfÃcie que satisfaz S maior que ou igual a n(k^2-2k+n)}/{k(n-k)}=c(n,k) onde S representa o quadrado da norma da segunda forma fundamental AlÃm disso vamos mostrar que no caso compacto a integral sobre M de S à menor que ou igual a c(n,k)vol(M) ocorrendo igualdade somente no toro de Clifford
34

Deformabilidade sobre S^1 a livre de ponto fixo para auto-aplicações de T-fibrados e Reidemeister sobre S^1 / Deformability over S^1 of self-maps of T-bundles into a fixed point free map and Reidemeister over S^1

Prado, Gustavo de Lima 25 March 2010 (has links)
Classificação das auto-aplicações de fibrados, com fibra toro, que preservam fibra sobre o círculo, com a propriedade de poderem ser deformadas sobre o círculo a uma aplicação livre de ponto fixo. Ainda, investigamos a relação entre o número de Reidemeister sobre o círculo e a propriedade acima / Classification of all fiber-preserving self-maps of torus bundles over the circle by the property of being able to deform them over the circle into a fixed point free map by a fiberwise homotopy over the circle. We also investigate the relationship between Reidemeister number over the circle and the property above
35

A Batalha de Toro

Encarnação, Marcelo Augusto Flores Reis da January 2011 (has links)
Esta dissertação pretende estudar a entrada do exército de Afonso V em Castela em 1475, observando dois pontos de vista - um politico e outro militar, utilizando uma metodologia comparada entre fontes portuguesas, castelhanas e aragonesas. Procurou-se analisar a complexidade dos diferentes interesses e das distintas visões da realidade, em particular a partir das fontes cronísticas. Assim, à morte de Enrique IV, em 12 de Dezembro de 1474, Afonso V, crendo ser o legitimo rei de Castela, por responder ao ultimo desejo do rei defunto e por desposar a sobrinha Juana, reuniu apoios em Portugal, assegurou forças em Castela e pensou que com elas seria aceite como rei de Castela. A campanha, que inicialmente conheceu algum sucesso com o cerco falhado que Fernando I de Castela lançou ao Africano, em Toro, com as conquistas de Toro e Zamora e com a batalha de Baltamis, foi pendendo para o lado dos Reis Católicos a partir do momento em que conseguem assegurar mais apoios e, especialmente, a partir do ponto de não retorno- a batalha de Toro, a 1 de Março de 1476. Ao longo destes quatro anos de guerra não houve somente uma contenda politica entre dois reinos. Travou-se um jogo de forças entre a nobreza e a monarquia castelhanas, comum a outras monarquias tardo-medievais. A falta de apoios internacionais e a transição da opinião do príncipe D. João no sentido de procurar o entendimento contribuíram para a procura da paz, alcançada em 1479.
36

Punta Toro Virus Infection in Mice: Strain Differences in Pathogenesis and Regulation of Interferon Response Pathways

Mendenhall, Michelle 01 May 2009 (has links)
The Adames strain of Punta Toro virus (PTV-A) causes acute hepatic disease in hamsters and mice similar to that seen in natural Rift Valley fever virus (RVFV) infection, while the Balliet strain (PTV-B) is apathogenic. The ability of PTV-A to suppress the interferon (IFN) response has been demonstrated in hamsters and is thought to be a contributing factor to PTV-A's pathogenicity in hamsters. PTV-B is not assumed to exhibit this IFN-antagonistic activity, as it stimulates production of significantly higher IFN-β levels. To elucidate the role of IFN in resistance of mice to PTV-B infection, we utilized mice deficient in a critical IFN signaling protein, STAT-1. We found that these mice were drastically more susceptible to PTV-B, which caused 100% lethality compared to 0% in their wild-type counterparts. STAT-1 deficient mice were also more susceptible to PTV-A, as these mice succumbed to infection significantly earlier than wild-type mice (p=0.0058). We sought to determine whether PTV-A's IFN-antagonistic mechanism is functional in mice by examining expression of IFN-β in primary macrophages infected with either strain. We found that IFN-β protein concentration is higher in samples taken from PTV-B-infected cells. We employed quantitative PCR arrays specific to IFN signaling and response pathways to evaluate changes in gene expression throughout the course of infection with either virus strain. We found several genes with differentially regulated expression between PTV-A- and PTV-B-infected macrophages, including Ifnβ1 and multiple Ifnα subtypes. Also, several genes coding for inflammatory and chemotactic molecules, Cxcl11, Cxcl10, Cxcl9, Vcam1, and Il6, demonstrated increased expression in PTV-B samples compared to PTV-A. Of particular interest, Isg20, a 3'-5' exonuclease with specificity for single-stranded RNA, was stimulated ~2-fold higher by PTV-B, and Iigp1, from the family of GTPases associated with host defense against intracellular pathogens, was stimulated ~2.7-fold higher by PTV-B. The individual functions of each of these genes in mouse resistance to PTV-B could be a focus of future studies to better understand essential host defense mechanisms to phleboviral infection.
37

An Evaluation of Pit Latrines and User Perception of Excrement in Ngäbe Communities in Panama

Libby, James A. 25 May 2018 (has links)
At the end of the Millennium Development Goal (MDG) period in 2015, 2.3 billion people, 31% of the global population, still did not have access to even basic sanitation services. Of these people, 892 million still practice open defecation, and 856 million people use unimproved facilities such as pit latrines without a slab or platform or hanging latrines or bucket latrines (JMP 2017). Sustainable Development Goal (SDG) Target 6.2 now aims to achieve adequate and equitable sanitation and hygiene for all and sets the ambitious target of eradicating open defecation by 2030. While the number of people open defecating was reduced from 1229 million to 892 million between 2000 and 2015, that pace must accelerate to be achieved (JMP, 2017). In Panama, it is estimated that countrywide sanitation coverage is 71%, and rural coverage 54% (WHO/UNICEF, 2013). Even so, in indigenous areas like the Comarca Ngäbe-Buglé, only 25% of the population has adequate access to basic sanitation (ANAM, 2006). This research builds upon the research presented in (Hurtado, 2005, Kaiser, 2006, Mehl, 2008, and Wilbur, 2014). These theses researched double vault urine diverting (DVUD) latrines, or composting latrines, in indigenous communities in the province of Bocas del Toro and the Comarca Ngäbe-Buglé in Panama. Hurtado, Kaiser, and Mehl researched the design, construction, and pathogen destruction capabilities of composting latrines. Wilbur studied how human attitudes and perceptions serve as incentives or barriers to composting latrine use. In this research surveys, interviews, and observations were recorded in 6 indigenous Ngäbe communities in Bocas del Toro and the Comarca Ngäbe-Buglé. The study quantifies usage of ventilated improved pit (VIP) and basic pit latrines in these communities, assesses positive and negative perceptions of composting latrines, and determines perceptions of feces and the reuse of composted human excrement. The results reveal that of n=103 latrines 88.3% were completed and in use, but only 35.2% were properly covered. To promote proper usage of latrines, continued education and trainings need to be carried out in these communities. Respondents were also favorable to the use of composting latrines, with 61.2% of respondents saying they would be interested in building a composting latrine for their households. The main perceived benefit of composting latrines is the compost, and the most identified barrier to use was lack of prior experience. Other main barriers included user disgust and the amount of work it takes to own and operate the latrine. There were more identified incentives (12) than barriers (11) to composting latrine adoption. Respondents also reported they would react more favorably to their neighbor implementing the technology and using compost than their neighbor would react should the respondent do the same thing. These results indicate the importance of pilot projects in communities, allowing people to see the benefits of the technology and how it works before implementing a larger scale project. These projects would also reduce the stigma associated with being a first adopter. Statistical analysis revealed that the demographics of community, sanitation classification, gender, and primary occupation were significantly linked to survey statements used to measure perceptions on composting latrine use and the use of composted human excrement as a fertilizer. Age, gender, and household size were not found to have a statistically significant link to user perceptions on the same survey statements. Logistic regression analysis was then performed using SPSS statistical analysis software (version 24). The results of this research indicate the importance of setting up follow up trainings as many respondents had forgotten how to properly maintain their latrines. It also suggests the setup of pilot projects for composting latrines, as many respondents were favorable to the technology but did not want to try to own and operate a composting latrine without seeing a successful composting latrine first.
38

Mexican Cinema in a Global Age: The Films of Guillermo Del Toro, Alfonso Cuarón, and Alejandro González Iñárritu

Rusnak, Stacy S 14 December 2010 (has links)
This study investigates the participation of cinema in the continuing debates over Mexican national identity. Part one lays out the problem of defining “Mexicanness” in contemporary society, and demonstrates that during the 1990s a new attitude emerged amongst a younger generation that sought to redefine the image of the cosmopolitan Mexican urbanite. This section is devoted to the problematics of traditional discourses on Mexican identity, as well as to a theoretical shift away from a nationalist paradigm of identity formation towards a more flexible model that takes into consideration the global processes shaping contemporary Mexico. Part 2 analyzes three early Mexican films made by Guillermo Del Toro, Alfonso Cuarón, and Alejandro González Iñárritu, respectively Cronos (1993), Y tu mamá también (2001), and Amores perros (2000). I demonstrate through a heuristic model of the Real, Imaginary, and Symbolic how these films allegorize Mexico’s “coming to age tale” under the weight of political and economic changes. Part 3 shifts to the Hollywood films by these directors. Using a scalar concept, I illustrate how these directors’ works yield a new model for understanding the interconnectedness between the national and the transnational in a way that neither term is necessarily privileged, but rather coextensive.
39

Mexican Cinema in a Global Age: The Films of Guillermo Del Toro, Alfonso Cuarón, and Alejandro González Iñárritu

Rusnak, Stacy S 14 December 2010 (has links)
This study investigates the participation of cinema in the continuing debates over Mexican national identity. Part one lays out the problem of defining “Mexicanness” in contemporary society, and demonstrates that during the 1990s a new attitude emerged amongst a younger generation that sought to redefine the image of the cosmopolitan Mexican urbanite. This section is devoted to the problematics of traditional discourses on Mexican identity, as well as to a theoretical shift away from a nationalist paradigm of identity formation towards a more flexible model that takes into consideration the global processes shaping contemporary Mexico. Part 2 analyzes three early Mexican films made by Guillermo Del Toro, Alfonso Cuarón, and Alejandro González Iñárritu, respectively Cronos (1993), Y tu mamá también (2001), and Amores perros (2000). I demonstrate through a heuristic model of the Real, Imaginary, and Symbolic how these films allegorize Mexico’s “coming to age tale” under the weight of political and economic changes. Part 3 shifts to the Hollywood films by these directors. Using a scalar concept, I illustrate how these directors’ works yield a new model for understanding the interconnectedness between the national and the transnational in a way that neither term is necessarily privileged, but rather coextensive.
40

Toro marriage : a study of changing conjugal institutions

Perlman, Melvin L. January 1963 (has links)
No description available.

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