<p>Onboard cone beam computed tomography (CBCT) has become a widespread means of three-dimensional target localization for radiation therapy; however, it is susceptible to metal artifacts and beam-hardening artifacts that can hinder visualization of low contrast anatomy. Dual-CBCT provides easy access to techniques that may reduces such artifacts. Additionally, dual-CBCT can decrease imaging time and provide simultaneous orthogonal projections which may also be useful for fast target localization. However, dual-CBCT will suffer from large increases in scattered radiation due to the addition of the second source.</p><p>An experimental bench top dual CBCT system was constructed so that each imaging chain in the dual CBCT system mimics the geometry of gantry-mounted CBCT systems commonly used in the radiation therapy room. The two systems share a common axis of rotation and are mounted orthogonally. Custom control software was developed to ensure reproducible exposure and rotation timings. This software allows the implementation of the acquisition sequences required for the cross scatter avoidance and correction strategies studied.</p><p>Utilizing the experimental dual CBCT system cross scatter was characterized from 70-145 kVp in projections and reconstructed images using this system and three cylindrical phantoms (15cm, 20cm, and 30cm) with a common Catphan core. A novel strategy for avoiding cross-scatter in dual-CBCT was developed that utilized interleaved data acquisition on each imaging chain. Contrast and contrast-to-noise-ratio were measured in reconstructions to evaluate the effectiveness of this strategy to avoid the effects of cross scatter.</p><p>A novel correction strategy for cross scatter was developed wherein the cross scatter was regularly sampled during the course of data acquisition and these samples were used as the basis for low- and high- frequency corrections for the cross-scatter in projections. The cross scatter sampling interval was determined for an anthropomorphic phantom at three different sites relevant to radiation therapy by estimating the angular Nyquist frequency. The low frequency portion of the cross scatter distribution is interpolated between samples to provide an estimate of the cross scatter distribution at every projection angle and was then subtracted from the projections.</p><p>The high-frequency portion of the correction was applied after the low-frequency correction was applied. The novel high-frequency correction utilizes the fact that a direct estimate of the high-frequency components was obtained in the cross scatter samples. The high-frequency components of the measured cross scatter were subtracted from the projections in the Fourier domain, a process referred to as spectral subtraction. Each projection is corrected using the cross scatter sample taken at the closest projection angle. In order to apply this correction in the Fourier domain the high-frequency component of the cross scatter must be approximately stationary. To improve the stationarity of the high-frequency cross scatter component a novel two-dimensional, overlapping window was developed. The spectral subtraction was then applied in each window and the results added to form the final image.</p><p>The effectiveness of the correction techniques were evaluated by measuring the contrast and contrast-to-noise-ratio in an image quality phantom. Additionally, the effect of the high-frequency correction on resolution was measured using a line pair phantom.</p><p>Cross scatter in dual CBCT was shown for large phantoms to be much higher than forward scatter which has long been known to be one of the largest degrading factors of image quality in CBCT. This results in large losses of contrast and CNR in reconstructed images. The interleaving strategy for avoiding cross scatter during projection acquisition showed similar performance to cross scatter free acquisitions, however, does not acquire projections at the maximum possible rate. For those applications in which maximizing the acquisition rate of projections is important, the low- and high-frequency corrections effectively mitigated the effects of cross scatter in the dual CBCT system.</p> / Dissertation

In this research we present a model for medication adherence from information systems and technologies (IS/IT) perspective. Information technology applications for healthcare have the potential to improve cost-effectiveness, quality and accessibility of healthcare. To date, measurement of patient medication adherence and use of interventions to improve adherence are rare in routine clinical practice. IS/IT perspective helps in leveraging the technology advancements to develop a health IT system for effectively measuring medication adherence and administering interventions. Majority of medication adherence studies have focused on average medication adherence. Average medication adherence is the ratio of the number of doses consumed and the number of doses prescribed. It does not matter in which order or pattern patients consume the dose. Patients with enormously diverse dosing behavior can achieve the same average levels of medication adher­ence. The same outcomes with different levels of ad­herence raise the possibility that patterns of adherence affect the effectiveness of medication adherence. We propose that medication adherence research should utilize effective medication adherence (EMA), derived by including both the pattern and average medication adherence for a patient. Using design science research (DSR) approach we have developed a model as an artifact for smart interventions. We have leveraged behavior change techniques (BCTs) based on the behavior change theories to design smart intervention. Because of the need for real time requirements for the system, we are also focusing on hierarchical control system theory and reference model architecture (RMA). The benefit of using this design is to enable an intervention to be administered dynamically on a need basis. A key distinction from existing systems is that the developed model leverages probabilistic measure instead of static schedule. We have evaluated and validated the model using formal proofs and by domain experts. The research adds to the IS knowledge base by providing the theory based smart interventions leveraging BCTs and RMA for improving the medication adherence. It introduces EMA as a measurement of medication adherence to healthcare systems. Smart interventions based on EMA will further lead to reducing the healthcare cost by improving prescription outcomes.

The research related to designing portable monitoring devices for physiological signals has been at its peak in the last decade or two. One of the main obstacles in building such devices is the effect of the subject's movements on the quality of the signal. There have been numerous studies addressing the problem of removing motion artifact from the electrocardiogram (ECG) and photoplethysmography (PPG) signals in the past few years. However, no such study exists for the Impedance Plethysmography (IP) signal. The IP signal can be used to monitor respiration in mobile devices. However, it is very susceptible to motion artifact. The main aim of this dissertation is to develop adaptive and non-adaptive filtering algorithms to address the problem of motion artifact reduction from the IP signal.

Dans la pratique actuelle de la curiethérapie à bas débit, l'évaluation de la dose dans la prostate est régie par le protocole défini dans le groupe de travail 43 (TG-43) de l'American Association of Physicists in Medicine. Ce groupe de travail suppose un patient homogène à base d'eau de même densité et néglige les changements dans l'atténuation des photons par les sources de curiethérapie. En considérant ces simplifications, les calculs de dose se font facilement à l'aide d'une équation, indiquée dans le protocole. Bien que ce groupe de travail ait contribué à l'uniformisation des traitements en curiethérapie entre les hôpitaux, il ne décrit pas adéquatement la distribution réelle de la dose dans le patient. La publication actuelle du TG-186 donne des recommandations pour étudier des distributions de dose plus réalistes. Le but de ce mémoire est d'appliquer ces recommandations à partir du TG-186 pour obtenir une description plus réaliste de la dose dans la prostate. Pour ce faire, deux ensembles d'images du patient sont acquis simultanément avec un tomodensitomètre à double énergie (DECT). Les artéfacts métalliques présents dans ces images, causés par les sources d’iode, sont corrigés à l'aide d’un algorithme de réduction d'artefacts métalliques pour DECT qui a été développé dans ce travail. Ensuite, une étude Monte Carlo peut être effectuée correctement lorsque l'image est segmentée selon les différents tissus humains. Cette segmentation est effectuée en évaluant le numéro atomique effectif et la densité électronique de chaque voxel, par étalonnage stoechiométrique propre au DECT, et en y associant le tissu ayant des paramètres physiques similaires. Les résultats montrent des différences dans la distribution de la dose lorsqu'on compare la dose du protocole TG-43 avec celle retrouvée avec les recommandations du TG-186. / In current low dose rate brachytherapy practice, dose evaluation within the prostate is govern by the protocol defined by the task group 43 (TG-43) of the American Association of Physicist in Medicine. This task group assumes a homogeneous water based patient with invariable density. They also disregard the changes in photon attenuation through neighbouring brachytherapy sources. With the introduction of these simplifications, dose calculations are easily solved using an equation proposed in this protocol. Although this task group helped create a uniform practice of brachytherapy treatments between hospitals, it does not properly described the actual dose distribution within the patient. The current publication of TG-186 gives recommendations to study these dose distribution more realistically. The purpose of this Master's thesis is to apply these recommendations from TG-186 to obtain a more realistic description of the dose. In order to proceed, two sets of patient images are acquired with a dual energy computed tomography (DECT). These images are corrected for metallic artifacts, which are highly present in the scanned images, using DECT metallic artifact reduction algortithm, developped in this work. Afterwords, a Monte Carlo study can be performed by properly identifying the environment with human tissues. This segmentation is performed by evaluating the effective atomic number and electronic density of each voxel using a DECT stoichiometric calibration, and allocating the tissue having the closest resemblance to these physical parameters. The results show clear differences in dose distribution when comparing TG-43 protocole with TG-186 recommendations.

(EN) Evaluation is an inextricable part of perceiving artworks and therefore it is necessary to study it. Evaluation is always an evaluation of something, it presupposes certain knowledge and idea of what is being evaluated. Evaluation presupposes conceptualization. If we want to say something about art or better of our experience of it and want to be understood and believed, we will need to study our conceptual equipment we use. This paper offers a conceptual minimum, being important, almost inevitable for the evaluation of art. All encounters with art are connected to the consideration of authorship. Concept of the author seems to be with the concept of art more then adherent. Nowadays authorship flounders between complete sovereignty and dissolution. There are theories of artworks, that leave or even protest against the connection between art and author. Art has a long tradition, but the contemporary notio of art is relatively young and conceptually very much laden. On the one side there is ignorance of its character, on the other there are tendencies to fix it forever. Man understanding art as an expression, perceives, looks for meaning and evaluates differently, then the one understands art as an institutinally given status. The manners of thinking art are decisive. The concept of art depends...

Master of Science / Department of Landscape Architecture / Regional and Community Planning / Stephanie A. Rolley / Community development and architecture approach the study of the city in distinct ways while sharing the purpose of creating or modifying the places we inhabit. Community development utilizes a scientific approach through the study of place-making, developing it from a socially based tradition, in other words, communities of place. Architecture considers the city like a work of art approaching the study from a physical perspective and emphasizing form. Architecture in this context is both an element of construction in space and the totality of the construction, the whole of a community’s modification of site. Developed from the point of view of an architect, this investigation challenges the distinction between architecture and community development exploring each perspective’s study of the city. Through a linear progression of framework diagrams, modified as the result of connecting concepts between the two disciplines, this investigation demonstrates how architecture and community development can achieve a unified framework for the study of the city.

Esta pesquisa propõe analisar o papel o dos artefatos na promoção da sociabilidade no Jardim da Luz, entre os anos de 1870 a 1930. As decisões políticas sobre os espaços públicos verdes tiveram suma importância, pois eram responsáveis pela inserção, reforma ou demolição de artefatos no espaço. Os artefatos, por sua vez, foram muito utilizados na composição das imagens presentes nos cartões postais e circularam pela cidade com o objetivo de exaltar os pontos modernos de São Paulo. No caso do Jardim da Luz, os postais circulados colaboraram para criar o imaginário a respeito do espaço como um local moderno e de sociabilidade. O local passou a ser usado para apresentações musicais, festas e encontros. Foram estudados três principais grupos no espaço: a elite paulistana, os trabalhadores e os fotógrafos lambe-lambe. O Jardim se tornou local representativo para esses grupos, um espaço de festas para alguns e para outros, ambiente de trabalho. Esta pesquisa, pelo estudo da cultura material, pretende compreender os usos dos espaços do Jardim da Luz como um espaço de sociabilidade e suas transformações ao longo do período em questão. / This research intends to analyse urban artifacts\' influence on Jardim da Luz\'s sociability from 1870 to 1930. Political decisions concerning green public spaces had extreme importance on it, as responsibles for artifacts insertion, reform or demolition ion the garden. Artifacts, in turn, were largelly used as background for postcard\'s which circulated through the city to exalt São Paulo\'s modern sights. In Jardim da Luz, Tthose postcards helped to create the ideia of a modern and social place in Jardim da Luz. It had begun to host musical presentations, parties and meetings. In this workstudy, were studied examined three major social groups which attended those events: elite from São Paulo, workers and street photographers. Jardim da Luz became a representative local for those groups, a party place for some and a work site for others. This research, through the study of material culture, intendsaims to understand Jardim da Luz\'s social usage and its transformation through the study of material culture through during the time studied.

Os potenciais evocados têm uma consagrada utilização em clínica. Sua obtenção é dificultada pela presença de outros sinais biológicos, de artefatos de movimento, de ruído eletrônico, de interferência da rede elétrica e de artefatos de estímulo. A média síncrona ou promediação é um método que elimina os sinais que não estejam sincronizados com a estimulação, incluindo os outros sinais biológicos, os artefatos de movimento, o ruído e a interferência. No entanto, esse método não consegue eliminar os artefatos de estímulo. Outros métodos devem ser usados para essa tarefa. Para esses métodos, a eliminação do artefato de estímulo é bem sucedida quando o artefato não se sobrepõe ao potencial evocado. Porém, para uma captação próxima ao local de estimulação, a sobreposição ocorre e dificulta a eliminação do artefato de estímulo. O objetivo deste trabalho foi o de estudar a variação da amplitude e latência do pico do potencial evocado e sua influência nas estimativas da amplitude, da latência e do erro quadrático médio. Para potenciais evocados em que houve sobreposição com o artefato, o erro médio quadrático sempre foi reduzido com a remoção do artefato de estímulo. O erro de medição da latência foi reduzido a praticamente zero, independentemente da amplitude do potencial evocado. Por outro lado, o método inseriu erro na medição da amplitude de potenciais evocados grandes. Por isso, nesse caso específico de atraso pequeno e amplitude grande, a medição da amplitude deve ser feita diretamente no sinal antes da remoção do artefato de estímulo. Comparando a ocorrência de sobreposição com os locais de captação do potencial evocado, pode-se afirmar que, para o modelo de artefato de estímulo usado neste trabalho, a necessidade de se aplicar o procedimento de remoção de artefato se restringiu aos potenciais evocados captados no cotovelo, para estimulação do nervo mediano tanto no punho quanto na mão. / Evoked potentials have been used in clinics. Their measurement is hindered by the presence of other biological signals, movement artifacts, electronic noise, power-line interference, and stimulus artifacts. Synchronous averaging is a method that eliminates the signals that are not synchronized with the stimulation, including other biological signals, movement artifacts, noise and interference. However, this method fails to eliminate stimulus artifacts. Other methods must be used in this task. Using these methods, one can obtain success in the stimulus artifact elimination, whenever the artifact does not superimpose with the evoked potential. Nevertheless, for a measurement close to the stimulation site, the superimposition is a fact that hinders the elimination of the stimulus artifact. The objective of this Masters thesis was to study the variation of the amplitude and latency of an evoked potential and verify their influence on the amplitude and latency estimates, as well as on the mean square error. For evoked potentials in which there was superposition, the mean square error was always reduced by the removal of the stimulus artifact. Latency measurement errors were reduced to zero, regardless of the evoked potential amplitude. However, this method inserted amplitude measurement errors for large evoked potentials. So, in the case of short delays and large amplitudes, amplitude measurements should be performed directly on the signal, before stimulus artifact removal. By comparing the presence of superposition with the evoked potential recording sites, one may state that, for the stimulus artifact model used in this work, the need to apply the artifact removal procedure was restricted to the evoked potentials recorded on the elbow, for median nerve stimulation both on wrist and hand.

Nesta dissertação ocorre a investigação sobre o espaço Porto do Sal (Belém/PA) e a paisagem material encontrada no lugar. Há a suposição de uma interferência do espaço insular amazônico sobre o Porto do Sal, devido aos acessos frequentes a este espaço estimulados pela atividade econômica do Porto, por meio de barcos. A pergunta fundamental se refere a descobrir quais elementos construtivos encontrados na paisagem do Porto revelam indícios de uma interferência do ambiente insular. O objetivo geral é a aproximação com o Porto do Sol, a ponto de obter um panorama amplo do seu modo de construir, que se desdobra desde a arquitetura das habitações até os artefatos. De modo específico está a busca pelo conhecimento do ambiente insular, seja por entradas presenciais nesse espaço, seja pelo amparo em autores que o investigaram; realizar aproximação etnográfica no Porto do Sal, para entendimento dos motivos que se revelam na ação construtiva deste lugar; analisar um grupo de autores que discutam os assuntos relacionados ao estudo, sendo eles: ARRUDA (2014), ISABELLE (2011), SANTOS (1996), JACQUES (2007), CERTEAU (2014), TUAN (1983), LOUREIRO (1995), dentre outros. Para o registro da paisagem do Porto do Sal, foram utilizados o diário de campo e fotografia da paisagem. Estão presentes no lugar elementos peculiares ao espaço insular amazônico - hábitos, modos de agir, falar, vestir, construir, habitar - e isto é demonstrado nos capítulos de discussão teórica e também por meio da organização de um panorama visual presente no \'Percurso imagético entre a Amazônia insular e o Porto do Sal - livro-relato da paisagem em estudo\', que encerra o volume. O sujeito amazônico, seus hábitos e as manifestações culturais que o envolvem são discutidos e mostrados ao longo do estudo, assim como o rebatimento desse contexto no Porto do Sal, que configura este lugar como o ponto de encontro entre as ilhas amazônicas e Belém, um reservatório da expressão do ambiente insular diluído pela cidade grande em contato. / In this dissertation we investigate the space of Porto do Sal (Belém/PA) and the material landscape found there. There is the assumption of an interference of the Amazonian insular space over Porto do Sal, dueto the frequent accesses to this space stimulated by the economic activity ofthe port, by means ofboats. The fundamental issue is related to the discovery of which constructive elements found in the landscape of Porto do Sal reveal evidences of an interference from the insular environment. The general objective is to promote an approximation with Porto do Sal, in order to obtain a wide panorama of its construction, which unfolds from the architecture of the dwellings to the artifacts. Specifically, the knowledge of the insular environment is sought, either by presence in that space or by the support of authors who investigated it; as well as performing an ethnographic approach with Porto do Sal, in order to understand the reasons that are revealed in the constructive action ofthis place; and analyzing a group of authors that discuss the subjects related to the study, such as: ARRUDA (2014), ISABELLE (2011), SANTOS (1996), JACQUES (2007), CERTEAU (2014), TUAN (1983), LOUREIRO (1995), among others. To record the landscape of Porto do Sal, the field diary and landscape photography were used. The elements peculiar to the Amazonian island space present in this place - habits, ways of acting, talking, dressing, building, inhabiting - are demonstrated in the theoretical discussion chapters and also through the organization of a visual panorama present in \'Percurso imagético entre a Amazônia insular e o Porto do Sal - livro-relato da paisagem em estudo\', which closes the volume. The amazonian subject, his habits and the cultural manifestations that surround him are discussed and shown throughout the study, as well as the projection of this context in Porto do Sal, which configures this place, like a meeting point between the Amazonian islands and Belém, as a reservoir of the expression of the insular environment diluted by the big city in contact.

"A wireless wearable battery-operated pulse oximeter has been developed in our laboratory for field triage applications. The wearable pulse oximeter, which uses a forehead-mounted sensor to provide arterial oxygen saturation (SpO2) and heart rate (HR) information, would enable field medics to monitor vital physiological information following critical injuries, thereby helping to prioritize life saving medical interventions. This study was undertaken to investigate if accelerometry (ACC)-based adaptive noise cancellation (ANC) is effective in minimizing SpO2 and HR errors induced during jogging to simulate certain motion artifacts expected to occur in the field. Preliminary tests confirmed that processing the motion corrupted photoplethysmographic (PPG) signals by simple Least-Mean-Square (LMS) and Recursive Least-Squares (RLS) ANC algorithms can help to improve the signal-to-noise ratio of motion-corrupted PPG signals, thereby reducing SpO2 and HR errors during jogging. The study showed also that the degree of improvement depends on filter order. In addition, we found that it would be more feasible to implement an LMS adaptive filter within an embedded microcontroller environment since the LMS algorithm requires significantly less operations."