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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.
101

Measurement Error and Misclassification in Interval-Censored Life History Data

White, Bethany Joy Giddings January 2007 (has links)
In practice, data are frequently incomplete in one way or another. It can be a significant challenge to make valid inferences about the parameters of interest in this situation. In this thesis, three problems involving such data are addressed. The first two problems involve interval-censored life history data with mismeasured covariates. Data of this type are incomplete in two ways. First, the exact event times are unknown due to censoring. Second, the true covariate is missing for most, if not all, individuals. This work focuses primarily on the impact of covariate measurement error in progressive multi-state models with data arising from panel (i.e., interval-censored) observation. These types of problems arise frequently in clinical settings (e.g. when disease progression is of interest and patient information is collected during irregularly spaced clinic visits). Two and three state models are considered in this thesis. This work is motivated by a research program on psoriatic arthritis (PsA) where the effects of error-prone covariates on rates of disease progression are of interest and patient information is collected at clinic visits (Gladman et al. 1995; Bond et al. 2006). Information regarding the error distributions were available based on results from a separate study conducted to evaluate the reliability of clinical measurements that are used in PsA treatment and follow-up (Gladman et al. 2004). The asymptotic bias of covariate effects obtained ignoring error in covariates is investigated and shown to be substantial in some settings. In a series of simulation studies, the performance of corrected likelihood methods and methods based on a simulation-extrapolation (SIMEX) algorithm (Cook \& Stefanski 1994) were investigated to address covariate measurement error. The methods implemented were shown to result in much smaller empirical biases and empirical coverage probabilities which were closer to the nominal levels. The third problem considered involves an extreme case of interval censoring known as current status data. Current status data arise when individuals are observed only at a single point in time and it is then determined whether they have experienced the event of interest. To complicate matters, in the problem considered here, an unknown proportion of the population will never experience the event of interest. Again, this type of data is incomplete in two ways. One assessment is made on each individual to determine whether or not an event has occurred. Therefore, the exact event times are unknown for those who will eventually experience the event. In addition, whether or not the individuals will ever experience the event is unknown for those who have not experienced the event by the assessment time. This problem was motivated by a series of orthopedic trials looking at the effect of blood thinners in hip and knee replacement surgeries. These blood thinners can cause a negative serological response in some patients. This response was the outcome of interest and the only available information regarding it was the seroconversion time under current status observation. In this thesis, latent class models with parametric, nonparametric and piecewise constant forms of the seroconversion time distribution are described. They account for the fact that only a proportion of the population will experience the event of interest. Estimators based on an EM algorithm were evaluated via simulation and the orthopedic surgery data were analyzed based on this methodology.
102

Modeling cure depth during photopolymerization of multifunctional acrylates

Boddapati, Aparna 16 February 2010 (has links)
The photopolymerization of multifunctional acrylates leads to the formation of a complex and insoluble network due to cross-linking. This characteristic is a useful property for stereolithography applications, where solid parts of the desired shape are cured using a pre-determined energy exposure profile. Traditionally, the required energy exposure is determined using a critical energy--depth of penetration, or Ec--Dp, model. The parameters Ec and Dp, are usually fit to experimental data at a specific resin composition and cure intensity. As a result, since the Ec--Dp model does not explicitly incorporate cure kinetics, it cannot be used for a different set of process conditions without first obtaining experimental data at the new conditions. Thus, the Ec--Dp model does not provide any insight when a new process needs to be developed, and the best processing conditions are unknown. The kinetic model for multifunctional acrylate photopolymerization presented here is based on a set of ordinary differential equations (ODE), which can be used to predict part height versus exposure condition across varying resin compositions. Kinetic parameter information used in the model is obtained by fitting the model to double bond conversion data from Fourier Transform Infrared Spectroscopy (FTIR) measurements. An additional parameter, the critical conversion value, is necessary for determining the formation of a solid part of the desired height. The initial rate of initiation, Ri, combines all the factors that impact part height, and therefore, it is an important quantity that is required in order to find the critical conversion value. The critical conversion value is estimated using the Ri and Tgel value from microrheology measurements. Information about network connectivity, which can be used to get properties such as molecular weight, cannot be derived from models using traditional mass-action kinetics for the cross-linking system. Therefore, in addition to modeling the reaction using the ODE based model, the results from a statistical model based on Kinetic Monte Carlo (KMC) principles are also shown here. The KMC model is applicable in situations where the impact of chain length on the kinetics or molecular weight evolution is of interest. For the present project, the detailed information from network connectivity was not required to make part height predictions, and the conversion information from the ODE model was sufficient. The final results show that the kinetic ODE model presented here, based on the critical conversion value, captures the impact of process parameters such as initiator concentration, light intensity, and exposure time, on the final part height of the object. In addition, for the case of blanket cure samples, the part height predictions from the ODE model make comparable predictions to the Ec--Dp model. Thus, the ODE model presented here is a versatile tool that can be used to determine optimum operating conditions during process development.
103

Statistical Modeling and Analysis for Survival Data with a Cure Fraction

XU, JIANFENG 26 January 2012 (has links)
The analysis of survival data with a possible cure fraction has attracted much interest in the last two decades. Various models and estimating methods have been proposed for such data and they have been applied in many fields, especially in cancer clinical trials. In the thesis, we consider some new general cure models, which include existing survival models as their special cases. We also consider a nonparametric estimation of cure rate. The estimator is proved consistent and asymptotically normal. We also consider the application of proportional density for cure data and the analysis of length-biased cure data. / Thesis (Ph.D, Mathematics & Statistics) -- Queen's University, 2012-01-26 09:53:08.127
104

Delayed-onset Polymer Cross-linking using Functional Nitroxyls

Hyslop, David 11 June 2012 (has links)
New polymer cure chemistry is described, wherein the onset of free radical cross-linking is delayed without compromising cure yields. The addition of an acrylate-functionalized nitroxyl, 4-acryloyloxy-2,2,6,6-tetramethylpiperidine-N-oxyl (AOTEMPO), to a peroxide-cure formulation quenches free radical activity during the initial stages of the cross-linking process, trapping alkyl radicals as alkoxyamines that bear acrylate functionality. Polymer cross-linking by macro-radical combination is suppressed until all nitroxyl is consumed, at which point radical oligomerization of polymer-bound acrylate groups generates the desired covalent network. As a result, cross-link density losses incurred during radical trapping are recovered during the oligomerization phase of the process. The effectiveness of this approach is demonstrated for a range of polymers, peroxide initiators, reaction temperatures and reagent loadings. Furthermore, AOTEMPO formulations are compared directly to other delayed-onset additives that are used in commercial practice. / Thesis (Master, Chemical Engineering) -- Queen's University, 2012-06-11 10:09:20.848
105

Le cadre juridique canadien et québécois relatif au développement parallèle de services privés de santé et l'article 7 de la Charte canadienne des droits et libertés

Laverdière, Marco. January 1998 (has links)
Thèses (LL.M.)--Université de Sherbrooke (Canada), 1998. / Titre de l'écran-titre (visionné le 20 juillet 2006). Publié aussi en version papier.
106

La responsabilité des établissements de santé privés /

Lantrès, Olivier. January 2001 (has links)
Texte remanié de: Th. doct.--Droit privé--Poitiers, 1999. / Bibliogr. p. 455-517. Index. L'ouvrage porte par erreur : ISSN 1298-8389.
107

Efeito de adesivos modificados por nanopartículas de TiO2 decoradas ou não com prata em diferentes propriedades /

Souza, Victor Trassi Fernandes Silva de. January 2017 (has links)
Orientador: Alessandra Nara de Souza Rastelli / Resumo: O presente estudo teve como objetivo a avaliação do efeito antibacteriano de sistemas adesivos modificados com nanopartículas (NPs) de dióxido de titânio (TiO2) decoradas ou não por prata (Ag) em diferentes concentrações, assim como o grau de conversão e a resistência de união à dentina sendo avaliada imediatamente e após três meses em saliva artificial. Os sistemas adesivos AdperTM Scotch Bond Multi Purpose e AdperTM Single Bond (3M Espe), e Clearfil SE Bond (Kuraray) foram modificados com concentrações 0 (controle); 1; 2 e 5% de NPs de TiO2 (com e sem Ag). Foram confeccionados espécimes cilíndricos em resina composta (FiltekTM Z250XT, 3M Espe) na cor A2 com matrizes metálicas (4x2mm), nos quais foram aplicados os sistemas adesivos modificados ou não, de acordo com as instruções dos fabricantes, para o teste de atividade antibacteriana por contato direto. Os espécimes foram colocados em placa de 24 poços e incubados por 18 horas a 37ºC em atmosfera de microaerofilia juntamente com 100μL de suspensão bacteriana padronizada contendo Streptococcus mutans e 900μL de BHI caldo + sacarose (1%). Para a contagem de unidades formadoras de colônias (UFC/mL), foram realizadas diluições seriadas com as soluções resultantes e 50μL dessas diluições foram plaqueadas em placas de petri contendo BHI ágar, sendo incubadas a 37ºC em 10% de CO2 por 48 horas. O grau de conversão foi avaliado por espectroscopia infravermelho por transformada de Fourier (FT-IR) para todos os adesivos modific... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present study evaluated the antibacterial effect, the degree of conversion and the micro-shear bond strength (immediate and after three months of water storage) of modified dental adhesive systems with TiO2 or Ag/TiO2 nanoparticles at different concentrations. The adhesive systems AdperTM Single Bond (SB), AdperTMScotchTM Bond Multi Purpose (3M Espe) (SBM) and Clearfil SE Bond (Kuraray) (CB) were modified with 1.0, 2.0 and 5.0 wt% of NPs. For the direct-contact test, sterilized specimens (n=36) were made using a metallic matrix (4x2mm) with the composite resin FiltekTMZ250 XT (3M Espe), on which the dental adhesive systems were applied according to the manufacturer's instructions. Both materials were photo-activated using a LED light-curing unit (LED Radii Plus, SDI). The specimens were placed in a 24-well plate with 100μL of Streptoccocus mutans standardized suspension on their surfaces, 900μL of BHI broth and incubated for 18 hours at 37ºC under an atmosphere containing 5% CO2. A six-fold serial dilution was performed with the resultant solutions. Fifty microliters (50μL) from each dilution was retrieved and spread on brain-heart infusion agar plates and incubated at 37°C under an atmosphere containing 5% of CO2 for 48h and the colony forming units (CFU's) were registered. For the evaluation of the DC, the specimens were made by the modification of the dental adhesive systems with all concentrations of nanoparticles and stored for 24hs at 37ºC in an incubator. The FTIR analysis was conducted using an attenuated total reflectance unit (ATR) at a 4cm-1 resolution and 64 scans. For the micro-shear bond strength test, One hundred and twenty six standardized dentin specimens were made from bovine incisors and divided into twenty-one groups. The control and modified adhesive systems were applied on the surfaces ...(Complete abstract electronic access below) / Mestre
108

“O santo é quem nos vale, rapaz! Quem quiser acreditar, acredita!”: práticas culturais e religiosas no âmbito das benzeções. Governador Mangabeira – Recôncavo Sul da Bahia (1950-1970)

Conceição, Alaíze dos Santos 25 July 2011 (has links)
Submitted by Oliveira Santos Dilzaná (dilznana@yahoo.com.br) on 2016-07-11T13:56:06Z No. of bitstreams: 1 Dissertação de Alaíze dos Santos Conceição.pdf: 820391 bytes, checksum: f516a9e9e2edd5174a4d92de9af1b5f1 (MD5) / Approved for entry into archive by Oliveira Santos Dilzaná (dilznana@yahoo.com.br) on 2016-07-25T15:25:09Z (GMT) No. of bitstreams: 1 Dissertação de Alaíze dos Santos Conceição.pdf: 820391 bytes, checksum: f516a9e9e2edd5174a4d92de9af1b5f1 (MD5) / Made available in DSpace on 2016-07-25T15:25:09Z (GMT). No. of bitstreams: 1 Dissertação de Alaíze dos Santos Conceição.pdf: 820391 bytes, checksum: f516a9e9e2edd5174a4d92de9af1b5f1 (MD5) / FAPESB / A pesquisa visa refletir acerca do universo cultural e religioso de Rezadeiras e Rezadores do município de Governador Mangabeira, Recôncavo sul da Bahia, nas décadas de 1950 a 1970, ressaltando as suas atuações nas comunidades que residem. Esses sujeitos históricos são integrantes das classes trabalhadoras e negras, os quais, motivados por questões econômicas, foram introduzidos no mundo do trabalho ainda na infância. Por fatores raciais, esses indivíduos, em sua maioria, alocados na segunda geração do pós-abolição, perambularam pela região em busca de melhores condições de vida, uma vez que as migrações pelas cidades do Recôncavo foram intensas até as décadas de 1950. Nesse sentido, buscou-se na elucidação de experiências cotidianas, sobretudo no universo do trabalho e nos aspectos religiosos da benzeção refletir acerca das identidades individuais e coletivas construídas no processo. A permanência dos elementos culturais presentes no âmbito das benzeções revela particularidades de uma população no que tange à relação que estabelecem com o sobrenatural, as doenças e a cura, suas expectativas, sentimentos e as possibilidades de transcendência da dura realidade. Sendo assim, as fontes utilizadas foram os periódicos Folha do Norte e o Jornal A tarde, assim como os depoimentos orais dos sujeitos históricos envolvidos no contexto histórico em análise. This research aims to reflect on the cultural and religious universe of women healer and man healer from the town Governador Mangabeira, Recôncavo Southern Bahia, from 1950 to 1970 decades, emphasizing their role in the communities where they live. These historical subjects make part of working and black classes, who, forced by economic necessities, were inserted into the working world yet in the childhood. Due to racial factors, most of them were allocated in the post- abolition second generation, which made them perambulate through the region in search of a better life, because migrations through Recôncavo Southern Bahia were very intense until 1950. Thus, by elucidating everyday experiences, especially in terms of working and religious blessing practice aspects, this work aimed to reflect on individual and collective identities built in the process. The permanency of cultural elements presented in the blessing practice extent reveals particularities of people regarding relations they firm to the supernatural, the sicknesses and cures, their expectations, feelings and the possibility to transcend from the tough reality. The following sources were used in this study: periodicals Folha do Norte and Jornal A tarde and oral testimonials of the historical subjects involved in the historical context under discussion.
109

"Fumo de negro": a criminalização da maconha no Brasil (c. 1890-1932)

Saad, Luísa Gonçalves January 2013 (has links)
Submitted by Oliveira Santos Dilzaná (dilznana@yahoo.com.br) on 2013-11-05T14:32:02Z No. of bitstreams: 1 DISSERTAÇÃO LUISA SAAD.pdf: 3162839 bytes, checksum: a968584caf2875d4160b5e1761886835 (MD5) / Approved for entry into archive by Ana Portela (anapoli@ufba.br) on 2013-11-18T18:36:30Z (GMT) No. of bitstreams: 1 DISSERTAÇÃO LUISA SAAD.pdf: 3162839 bytes, checksum: a968584caf2875d4160b5e1761886835 (MD5) / Made available in DSpace on 2013-11-18T18:36:31Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO LUISA SAAD.pdf: 3162839 bytes, checksum: a968584caf2875d4160b5e1761886835 (MD5) / Esta dissertação discute o processo histórico que culminou na proibição da maconha no Brasil em 1932. Para tanto, faz uma análise de teses médicas escritas desde o final do século XIX até as primeiras décadas do século XX. Destaca-se a atuação do médico e político Rodrigues Dória, cujos escritos serviram de base para tornar ilegal o uso da maconha que ele e outros médicos da época apontavam como um hábito trazido pelos escravos africanos, considerados raça inferior segundo ideias então em voga. No cenário político de uma Abolição e uma República recém-decretadas, se intensificou a visão de que os hábitos e práticas dos negros seriam obstáculos para concretizar os anseios por uma nação civilizada. O consumo de maconha constituía, assim, um dos empecilhos à modernização e ao progresso, uma vez que seus usuários tenderiam a adquirir comportamentos violentos, imorais ou insanos. A criminalização da maconha esteve associada à criminalização das práticas culturais de seus usuários, como foi o caso dos cultos afro-brasileiros como o candomblé. This paper discusses the historical process which culminated in the prohibition of marijuana in Brazil in 1932. Therefore, it analyzes medical theses written from the end of the nineteenth century until the first decades of the twentieth century. It highlights the role of the physician and politician Rodrigues Dória, whose writings were the basis for outlawing marijuana use. Rodrigues Dória and other doctors of that time indicated this use a habit brought by the African slaves, considered an inferior race, according to the ideias of that time. On a political scene of Abolition and Republic recently enacted, the view that the habits and practices of the black would be an obstacle to fulfill the aspirations of a civilized nation was intensified. Marijuana consumption thus constituted one of the obstacles to modernization and progress, since its users tended to get violent, immoral or insane. The criminalization of marijuana was associated with the criminalization of the cultural practices of its users, as it happened to the afro-brazilian cults, like candomblé.
110

Doença de feitiço, ações terapêuticas e os percursos de cura nos terreiros de umbanda e candomblé em Macapá-AP / Spell disease, therapeutic actions and healing pathways in umbanda and candomblé terrariums in Macapá-AP

Cordeiro, Maria da Conceição da Silva January 2016 (has links)
CORDEIRO, Maria da Conceição da Silva. Doença de feitiço, ações terapêuticas e os percursos de cura em terreiros de umbanda e candomblé em Macapá-AP. 2016. 228f. - Tese (Doutorado) – Universidade Federal do Ceará, Programa de Pós-Graduação em Sociologia, Fortaleza (CE), 2016. / Submitted by Gustavo Daher (gdaherufc@hotmail.com) on 2017-01-18T10:57:12Z No. of bitstreams: 1 2016_tese_mcscordeiro.pdf.pdf: 2171260 bytes, checksum: 5349faf0036f5763b3521a30f03c768c (MD5) / Approved for entry into archive by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2017-01-25T14:13:36Z (GMT) No. of bitstreams: 1 2016_tese_mcscordeiro.pdf.pdf: 2171260 bytes, checksum: 5349faf0036f5763b3521a30f03c768c (MD5) / Made available in DSpace on 2017-01-25T14:13:36Z (GMT). No. of bitstreams: 1 2016_tese_mcscordeiro.pdf.pdf: 2171260 bytes, checksum: 5349faf0036f5763b3521a30f03c768c (MD5) Previous issue date: 2016 / This ethnography deals with a form of physical-psychic illness known as spell disease. Its purpose is to understand the dynamics of this way of getting sick from the narratives of people who are said to be affected by this evil and how the healers conceive and treat the disease from their spiritual experiences according to their own logic centered in the terreiros of Umbanda and candomblé in the city of Macapá-AP. I propose an analysis of the various forms of manifestation of this phenomenon taking as a key analytical reading the cosmological conception of the Amazonian universe its therapeutic itineraries and the types of healing rituals triggered during the treatment. The ethnographic material described and analyzed here was obtained during field research (in-depth interviews and participant observation) in the period between 2013 and 2015 in the city of Macapá-AP. It turns out that belief in the spell is at the core of a cosmological system that admits the performance of hidden forces in their different ways of acting in daily life individual or collective. My ethnographic data indicate that the spell is a regulating belief in Amazonian life and that even in the face of the demands of modern life impelled by medical-scientific rationality, its power of interference in daily life is governed by the belief in the existence of unnatural diseases not explained by medical science . Despite the intense flow of preventive information and the implementation of curative and health care models capable of responding to the various diseases present in modern life they were not enough to suppress the ideas and cultural values ​​of these individuals adopting the traditional. / Esta etnografia trata de uma modalidade de adoecimento físico-psíquico conhecido como doença de feitiço. Tem por objetivo compreender a dinâmica desse modo de adoecer a partir das narrativas de pessoas que se dizem afetadas por esse mal e de que modo os curandeiros concebem e tratam a doença a partir de suas experiências espirituais de acordo com uma lógica própria centrada nos terreiros de umbanda e candomblé na cidade de Macapá-AP. Proponho uma análise das diversas formas de manifestação desse fenômeno tomando como chave de leitura analítica a concepção cosmológica do universo amazônico seus itinerários terapêuticos e os tipos de rituais de cura acionados no decorrer do tratamento. O material etnográfico aqui descrito e analisado foi obtido durante a pesquisa de campo (entrevistas em profundidade e observação participante) no período entre 2013 e 2015 na cidade de Macapá- AP. Verifica-se que a crença no feitiço está no cerne de um sistema cosmológico que admite a atuação de forças ocultas em suas diferentes formas de agir na vida cotidiana individual ou coletiva. Meus dados etnográficos indicam que o feitiço é uma crença reguladora da vida amazônica e que mesmo diante das demandas da vida moderna impelida pela racionalidade médico-cientifica seu poder de interferência no cotidiano é gerido pela crença na existência de doenças não naturais não explicadas pela ciência médica. Não obstante o intenso fluxo de informações preventivas e a implementação de modelos curativos e de cuidados em saúde capazes de responder às diversas doenças presente da vida moderna não foram suficientes para suprimir as ideias e os valores culturais desses indivíduos que adotam as concepções e práticas tradicionais de cura associadas ou não aos novos métodos mesmo no contexto urbano.

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