A voz é a principal ferramenta de comunicação da espécie humana e quase 70% da população economicamente ativa dos países desenvolvidos dependem direta ou indiretamente dela em sua profissão. Sua produção deve-se ao funcionamento harmônico de sistemas fisiológicos distintos, nos quais a laringe desempenha um importante papel. É nela que as funções de deglutição, respiração e fonação se encontram e também onde o pulso glotal é formado durante a passagem do ar pelas pregas vocais. Se os nervos e músculos da região por alguma razão são lesionados, o funcionamento dessas funções é prejudicado, causando sérios danos à qualidade de vida do indivíduo. Em virtude disso, diversas pesquisas tem sido realizadas visando adquirir informações que auxiliem as tomadas de decisões clínicas e cirúrgicas. Embora diversos avanços tenham sido realizados no campo de modelagens das pregas vocais e nos estudos da laringe, modelos baseados em geometrias de pacientes específicos que possam colaborar mais ativamente no planejamento cirúrgico, permanecem um desafio. Nesse sentido, este trabalho apresenta o desenvolvimento de um modelo computacional tridimensional, com base em imagens de tomografia computacional. Tendo por objetivo impulsionar a modelagem das características fisiológicas de pacientes reais e assim proporcionar maiores informações para tomadas de decisões. Esse modelo foi utilizado em simulações de escoamento de fluido solucionadas por elementos finitos, apresentando possibilidades satisfatórias de contribuir para avanços na modelagem de pacientes com patologias e em abordagens interativas, tal como interferências nos modelos virtuais por interfaces hápticas e simulações virtuais de cirurgia da laringe. / The voice is the main instrument for communication of human beings and almost 70% of the economically active population in the developed countries depends, directly or indirectly, on it for their profession. Its production is due to the harmonious interaction of different physiological systems, in which the larynx plays an important role. The larynx is involved in the deglutition, breathing and phonation functions and it is where the glottal pulse is formed during airflow through the vocal folds. If the nerves and muscles in this region for some reason are injured, this functions are adversely affected, causing serious damages to the individuals quality of life. As a result, several researches have been carried out, aiming at acquiring information that help in the clinical and surgical decision making. Although many progresses had been reached in the field of vocal folds modeling and in larynx studies, patientspecific geometry modeling that may take an active part in the surgical planning are still a challenge. In this regard, this work presents the development of a threedimensional computational model, based on images from computed tomography (CT) scans. This model was used in fluid flow simulations, solved by finite element analysis, showing satisfactory possibilities for contributions to progresses in the modeling of patients with lesions and in interactive approaches, such as interferences in the models with haptic interface and virtual surgery of the larynx.

This Master's thesis focuses on the influence of socioeconomic status on the morphology of the mandible of individuals from the early medieval burial area in Mikulčice. This hillfort was an important center of power of the Great Moravian Empire with a stratified society. This work compares 2 different approaches on how to divide the inhabitants. The first of them is the division of individuals according to the location of graves into individuals from the castle, sub-castle, and hinterland. The second approach is the division of individuals according to the richness of grave equipment into individuals with rich and poor grave equipment. A different social status is associated mainly with different diets. Therefore, the attachments of the masticatory muscles are the most affected areas. A total of 132 individuals (59 males and 73 females) were analyzed. The material was evaluated by methods of geometric morphometrics. The used methods were CDP DCA, GPA, two-sample t-test, PCA, MANOVA, and SVM. Sexual dimorphism was observed in all sub-groups of the Mikulčice population. Men have larger mandibles with rami wider apart. The biggest differences are between individuals from the castle, the smallest between individuals with rich grave equipment. The distribution of individuals based on the location of...

Yes / Previous studies have reported that the ageing method of Suchey-Brooks (pubic bone) and some of the features applied by Lovejoy et al. and Buckberry-Chamberlain (auricular surface) can be confidently performed on 3D visualizations from CT-scans. In this study, seven observers applied the Suchey-Brooks and the Buckberry-Chamberlain methods on 3D visualizations based on CT-scans and, for the first time, on 3D visualizations from laser scans. We examined how the bone features can be evaluated on 3D visualizations and whether the different modalities (direct observations of bones, 3D visualization from CT-scan and from laser scans) are alike to different observers. We found the best inter-observer agreement for the bones versus 3D visualizations, with the highest values for the auricular surface. Between the 3D modalities, less variability was obtained for the 3D laser visualizations. Fair inter-observer agreement was obtained in the evaluation of the pubic bone in all modalities. In 3D visualizations of the auricular surfaces, transverse organization and apical changes could be evaluated, although with high inter-observer variability; micro-, macroporosity and surface texture were very difficult to score. In conclusion, these methods were developed for dry bones, where they perform best. The Suchey-Brooks method can be applied on 3D visualizations from CT or laser, but with less accuracy than on dry bone. The Buckberry-Chamberlain method should be modified before application on 3D visualizations. Future investigation should focus on a different approach and different features: 3D laser scans could be analyzed with mathematical approaches and sub-surface features should be explored on CT-scans

<p>The need to understand and accurately assess the health risks of low dose ionizing radiation is more important now than ever before. The global applications of ionizing radiation in medicine, mining, manufacturing, and the nuclear industry have increased exponentially in recent years. Parallel to this increase are the health concerns regarding occupational and medical exposures to radiation. The research presented here investigates the biological and health effects of ionizing radiation, specifically from medical diagnostic exposures.</p> <p>Medical diagnostic procedures such as x-rays and computed tomography (CT) scans account for a notable portion of the public's exposure to ionizing radiation. The health risk to humans associated with these low dose exposures is unknown. Often times they are correlated with risk estimates derived from much higher radiation doses. There is no doubt that very high dose ionizing radiation can be harmful; however, the same notion does not exist regarding exposures to low dose ionizing radiation such as that from medical diagnostic CT exposures.</p> <p>The objective of this research is to address the effects and risks associated with diagnostic CT scans. This research focuses on the biological outcome of cancer which remains a primary concern in health care and the development of radiation risk policies. The investigation utilized various mouse models that have differing sensitivities to radiation and susceptibilities to developing radiation-induced cancer.</p> <p>Results from this research found that low-dose diagnostic CT scans do not increase risk and can, in fact, induce protective effects. The hypothesis that harmful effects increase linearly with radiation dose is not supported by this research. With low doses of CT scans, protective biological effects such as reduced chromosomal aberrations, decreased radiation-induced oxidative DNA damage, and enhanced clearance of damaged cells have been observed. In cancer-prone mice, CT scans can increase longevity and reduce cancer risk by delaying the latency of specific cancers.</p> <p>This research advances the understanding of the biological effects and health risk associated with low-dose medical diagnostic procedures. This research is timely and important to allow medical practitioners, policy makers, and regulators to make informed decisions about using ionizing radiation in the clinic. Such knowledge is valuable as better, more complex, and perhaps more damaging modalities are being used to image and manage disease.</p> / Doctor of Philosophy (PhD)