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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.
251

Método ultrassônico para avaliação da viscosidade e do coeficiente de compressibilidade durante o processo de cura de resinas / Ultrasonic method for assessing the viscosity and compressibility values during the curing process of resins

Newton Alves Maia 18 January 2010 (has links)
Durante a cura, ou seja, durante o processo de reticulação, resinas sofrem alterações irreversíveis em suas propriedades químicas e físicas, como, por exemplo, alterações significativas em seu coeficiente de compressibilidade (inverso do módulo de compressão volumétrico) e em sua viscosidade. A variação destas propriedades, ao longo de uma dimensão (direção) no interior de uma resina em processo de cura, pode ser obtida a partir de técnicas ultrassônicas baseadas no princípio pulso-eco, que permite a estimativa da velocidade de propagação e das atenuações das ondas. Antes da cura, as resinas apresentam velocidades de propagação entre 1600 e 1800 m/s, com viscosidade e atenuação pequenas. Durante o processo de cura ocorre um aumento notável da viscosidade, que causa grandes atenuações na onda ultrassônica. Chegando ao final do processo de cura, tanto a atenuação quanto a viscosidade voltam a diminuir. Após a reticulação, a velocidade de propagação pode ser superior a 2500 m/s. Visto que a densidade varia pouco durante a cura, a alteração de velocidade, observada durante a cura, pode ser atribuída às mudanças no módulo de compressão volumétrico da resina. O método pulso-eco descrito nesta dissertação permite monitorar, de forma não invasiva, a variação da viscosidade e a variação do coeficiente de compressibilidade durante o tempo de cura de uma resina epóxi, ao longo da direção de propagação de uma onda ultrassônica. / During the curing process, i.e. crosslinking process, resins suffer significant and irreversible changes on theirs chemical and physical properties, as the alterations in the compressibility coefficient (the inverse of bulk modulus) and in the viscosity. The changes in these properties along a direction inside of a resin, under a curing process, can be estimated with techniques based on pulse-echo ultrasonic waves. With these techniques is possible to obtain the ultrasonic wave speed and the attenuation imposed on the wave by a resin under curing. Before the cure, resins have speeds of wave propagation between 1600 and 1800 m/s, low attenuation and low viscosity. As the curing process evolves, there is a remarkable increase of viscosity, which causes great attenuations. After that, and until the end of the curing process, the viscosity and the attenuation decrease. After the cure and solidification, the wave speed may reach values up to 2500 m/s. Since the density almost does not vary during the cure, the changes in wave speed can be attributed to changes in the resins bulk modulus. The pulse-echo method, described in this dissertation, allows the monitoring, in a no invasive way, of the variation of the bulk modulus and the changes in viscosity along a direction of propagation of an ultrasonic wave, during the curing process of an epoxy resin.
252

Psychologická intervence ve zdravotnických zařízeních / Psychological intervention at medical care

JIRÁSKOVÁ, Marcela January 2010 (has links)
Diploma thesis deals with the psychological care and psychological guidance and their potentialities and availability for people or their close ones, who need help in period of diseases or disease effects. There is only psychiatrist-consultation care of psychic condition of patients in most of medical centres, but all diseases affect the psychic condition, even for patient´s close ones. Good psychic condition linked up with changed social condition is very important for successful cure. If the patients have low stress tolerance there is a risk, that every disease causes the hard life situation. Psychological care and cooperation with the doctor, medical staff, rehabilitation and social workers also as the communication competence can highly increase the quality of life of patients and their relatives.
253

Fatores associados à recidiva, ao abandono e ao óbito no retratamento da tuberculose pulmonar / Factors associated with recurrence, abandonment and death in the retreatment of pulmonary tuberculosis

Patricia Ferreira de Paula 18 March 2008 (has links)
RESUMO Objetivo: Investigar fatores associados à recidiva, retratamento por abandono e óbito entre retratados por abandono para pacientes com TB pulmonar, de ambos os sexos, maiores que treze anos, residentes em área periférica do município de São Paulo. Material e Métodos: Estudos de caso-controle não pareado aninhado a uma coorte prospectiva de pacientes com TB pulmonar confirmada por cultura, selecionados entre 2001 e 2002 e acompanhados até 2006. Os casos foram pacientes que apresentaram recidivas, retratamento por abandono e óbito entre retratados por abandono; os controles foram pacientes com cura sem retratamento. Os dados foram obtidos mediante aplicação de questionários estruturados aplicados à época do ingresso no estudo e por entrevista domiciliar em 2004 e 2006, complementados por informação da Vigilância de TB. Na investigação dos fatores associados à recidiva, ao retratamento por abandono e óbito entre retratados por abandono, esses três desfechos foram tomados como variáveis dependentes e como variáveis independentes, as exposições de interesse. As odds ratio (OR) brutas e ajustadas foram estimadas com os respectivos intervalos de 95% de confiança pela regressão logística multivariada não condicional. A importância das variáveis para o modelo final foi avaliada através do teste da razão de verossimilhança, utilizando-se p<0,05. Resultados: As variáveis associadas à recidiva e ajustadas para sexo e idade independentemente das demais foram: co-infecção com HIV (OR=9,3; IC95%= 1,6 - 54,1), contato domiciliar prévio (OR= 2,2; IC95% = 0,8 - 6,2), caso de TB no domicílio após o paciente (OR= 3,8; IC95%= 1,2 - 12,8); diabetes (OR=1,6; IC95%= 0,3 - 7,7), MDR (OR=15,5; IC95%= 1,2 - 200,5). As variáveis associadas ao retratamento por abandono ajustadas para sexo e idade independentes das demais variáveis foram: TBMDR (OR=38,7; IC95%= 2,9 - 515,3), co-infecção com HIV (OR=24,8; IC95%= 3,8 - 163,0), história de alcoolismo (OR= 4,2; IC95%=1,1 - 17,5) e internação por complicações de TB (OR= 7,2; IC95% =2,5 - 21,0). As variáveis associadas ao óbito entre retratados por abandono ajustadas para sexo e idade independente das demais e foram: TBMDR (OR=152,4; IC95%= 9,8 - 237,4), co-infecção com HIV (OR=29,0; IC95%=7,1 -1 19,1), alcoolismo (OR=11,8; IC95%=1,3-102,8) e regime prisional (OR=5,0; IC95%= 1,0-25,8). Conclusões: Os resultados apresentados apontam grupos de maior risco para retratamento por TB por recidiva, abandono de tratamento e óbito que devem ser considerados no aperfeiçoamento do DOTS em nosso país. / ABSTRACT Objective: Investigate factors associated to relapse, re-treatment by default and death among patients retreated by default for patients with pulmonary tuberculosis, of both sexes, more than thirteen years old, living in the periphery of the city of São Paulo. Material and Methods: A nested case-control study not paired to a prospective cohort of pulmonary tuberculosis patients confirmed by culture, selected between 2001 e 2002 and followed up until 2006. Cases were patients who had relapses, re-treatment by default and death among patients retreated by default; controls were patients with cure without re-treatment. The data were obtained through application of structured questionnaires applied at the time of entry in the study and interview at home in 2004 and 2006, supplemented by information from the surveillance of TB and Information System Mortality of the Foundation SEADE. Relapse, re-treatment by default and death among patients retreated by default were taken as dependent variables and the variables of interest as independent. Crude and adjusted odds ratio (OR) and its 95% confidence interval were calculated by multiple logistic regression not conditional. Statistical significance was assessed by the likelihood ratio test with p < 0.05. Results: The variables associated independently with relapse and adjusted for sex and age were: case of MDR-TB (OR=15.5; 95% CI: 1.2-200.5), co-infection with HIV (OR=9.3 ,95%CI: 1.6-54.1), diabetes (OR=1.6, 95% CI: 0.3-7.7), previous household contact with TB (OR=2.2, 95% CI: 0.8-6.2) and TB at home after patient studied (OR=3,8, 95% CI: 1,2-12,8). The variables associated independently with the retreatment of default and adjusted for sex and age were: case of MDR-TB (OR = 38.7, 95 % CI: 2.9-515.3), co-infection with HIV (OR=24.8, 95% CI: 3.8-163.0), alcohol abuse (OR=4.2, 95% CI: 1.1-17.5) and hospitalization to TB complications (OR=7.2, 95% CI: 2.5-21.0). The variables associated independently with death among patients retreated by default and adjusted for sex and age were: case of MDR-TB (OR=152.4, 95% CI: 9.8-237.4), co-infection with HIV (OR=29.0, 95%CI: 7.1-119.1), alcohol (OR=11.8, 95% CI: 1.3-102.8) and prison system (OR=5.0, 95%CI: 1.0-25.8). Conclusions: The results presented here show groups of higher risk among TB patients for re-treatment by relapse, treatment default and death among re-treated by default to be considered in the improvement of DOTS in our country.
254

Pesquisa de Mycobacterium spp. em queijos minas meia cura obtidos em feiras-livres da cidade de São Paulo / Recovery of Mycobacterium spp. in meia cura minas cheese from open markets of the São Paulo city

Patrícia Rossi Moriconi 13 September 2013 (has links)
O gênero Mycobacterium spp. compreende microrganismos saprófitas e patogênicos de interesse em saúde animal e humana. A espécie M. bovis, que causa tuberculose nos animais, é excretada através do leite de bovinos infectados e tem no consumo de leite cru e seus derivados uma importante via de transmissão para o homem, causando uma doença tão grave quanto à causada pelo M. tuberculosis. Como a doença nos animais é endêmica no Brasil e o queijo minas meia cura é normalmente fabricado com leite cru e muito apreciado pelo consumidor paulistano, amostras desse produto, obtidas em feiras-livres, foram analisadas quanto à ocorrência de micobactérias. As amostras foram descontaminadas pelo método HPC 1,5%, semeadas em meio Stonebrink-Leslie (incubadas a 37ºC/90 dias) e as colônias suspeitas, submetidas à reação de PCR TB multiplex e sequenciamento nucleotídico. Em 12% das amostras (16/133) foram isoladas 26 colônias de Mycobacterium spp., tendo sido identificadas 6 espécies, todas ambientais: Mycobacterium fortuitum, M. confluentis, M. elephantis, M. novocastrense, M. sphagni e M. arupense; 7 isolados, no entanto, permaneceram sem caracterização quanto à espécie. O M. fortuitum é um patógeno oportunista importante em saúde pública, sem que haja, entretanto, evidências de transmissão alimentar; o M. novocastrense, M. arupense e M. elephantis também têm sido consideradas espécies com potencial patogênico ao ser humano. Os resultados sugerem, tal como era esperado, que a frequência e a carga inicial de M. bovis em queijo Minas meia cura sejam baixas, mas se deve considerar que a metodologia empregada, por falta de outra específica, não privilegia a detecção em cenário de baixa carga inicial do agente acompanhada por alta carga contaminante. Sugerem também a necessidade de se avaliar a importância da transmissão alimentar de micobactérias não tuberculosas, especialmente para indivíduos imunossuprimidos. / Mycobacterium genus consists of saprophytic and pathogenic microorganisms of interest in animal and human health. M. bovis specie, which causes tuberculosis in animals, is excreted through the milk of infected cattle and the consumption of raw milk and its derivatives is an important route of transmission to humans, causing a disease as serious as the one caused by M. tuberculosis. Considering that the disease in animals is endemic in Brazil and that minas meia cura cheese cure is usually made from raw milk and much appreciated by paulistano consumer, samples of the product acquired in open markets, were analyzed for the occurrence of mycobacteria. The samples were decontaminated by the method HPC 1.5%, sown in Stonebrink-Leslie medium (incubated at 37 ° C/90 da ys) and the suspected colonies, submitted to PCR TB multiplex and nucleotide sequencing reaction. In 12% of samples (16/133) were isolated 26 colonies of Mycobacterium spp. and 6 species have been identified, all of them are environmental Mycobacterium fortuitum, M. confluentis, M. elephantis, M. novocastrense, M. sphagni and M. arupense; 7 isolates, however, remained without characterization for the specie. M. fortuitum is an important opportunistic pathogen in public health, without, however, evidence of being transmitted by food; M. novocastrense, M. arupense and M. elephantis species have also been considered potentially pathogenic to humans. The results suggest that the frequency and/or contamination load of M. bovis in meia cura Minas cheese is (are) low (s). We have to consider, however, that this result may have been influenced by the absence of an analytical method capable of identifying the agent in the food matrix in which a low load of microorganism is expected, accompanied by high load of contaminants. Also suggest the need to evaluate the possible importance of foodborne non-tuberculous mycobacteria, especially for immunocompromised individuals.
255

"E aqui enloqueceo" : a alienação mental na Porto Alegre escravista, c. 1843 - c. 1872

Lorenzo, Ricardo de January 2007 (has links)
O objetivo desta investigação foi analisar o universo daqueles indivíduos internados na Santa Casa de Misericórdia de Porto Alegre entre os anos de 1843 e 1872 com o diagnóstico de "alienação mental", ou outro análogo. Para isso, examinei a regulamentação da cidade através das funções normativas e fiscalizadoras da Câmara Municipal e do Código de Posturas. Fiz uma leitura das discussões dos parlamentares provinciais acerca do trato com os inválidos e os vadios, e procurei traçar o perfil da população da capital rio-grandense, cidade escravista e hierarquizada. A Santa Casa, especialmente a partir da criação do seu Asilo de Alienados, foi apresentada como locus principal de recolhimento desses indivíduos, numa atuação muitas vezes associada ao poder policial. Políticas que envolviam a caridade e o controle dos grupos sociais marginalizados, nos quais cativos, libertos e pobres eram os alvos preferenciais. Nesse sentido, ficou evidente que os confinamentos muitas vezes se apresentavam como repressão ao não-trabalho e aos indivíduos insubmissos. Por outro lado, a definição do que era loucura implicava em diferentes níveis de prevalência dos diagnósticos dos médicos. As variações entre as concepções acadêmicas, o entendimento popular sobre as artes de curar e as disputas entre os médicos e as diversas instâncias de poder - como a policial e a judicial - foram aspectos considerados nas observações dos episódios de confinamento. Finalmente, por se tratar de uma sociedade escravista, e a ainda que as fontes analisadas não permitissem uma resposta aprofundada, busquei o entendimento possível sobre a circulação das concepções de africanos e seus descendentes a respeito da doença e da cura. / The objective of this research was to analyze the universe of those interned at the Santa Casa de Misericordia de Porto Alegre between the years of 1843 and 1872 with a diagnosis of "mental alienation", or other analogue. For this, examined the regulation of the city through the regulatory and supervisory functions of the City Council and the Code of Posturas. I have read the discussions of the provincial parliamentarians about the deal with the invalid and idles and I tried to draw the profile of the population from Porto Alegre, proslavery and hierarchical city. The Santa Casa, especially from the creation of its Asylum of Alienated, was presented as a main locus of collection of these individuals, in a performance often associated with the police power. Policies involving the charity and control of marginalized social groups, in which captives, and poor freed were particularly targeted. Thus, it was clear that confines often presented as if the prosecution does not-work and unsubmissive individuals. Moreover, the definition of what was meant madness on different levels of prevalence of diagnoses of doctors. The variations between the academic ideas, the popular understanding of the arts to heal and disputes between doctors and the various bodies of power - such as Police and Justice - aspects were considered in the remarks of episodes of confinement. Finally, as a proslavery society, and even if the sources analyzed not allow a response depth, sought the understanding on the possible movement of conceptions of Africans and their descendants about the disease and cure.
256

Fotoativação de resina composta por diferentes fontes de luz e avaliação da profundidade de polimerização por diversos métodos / Photoactivation of composite resin by different light sources and evaluation of depth of cure by several methods

Aline Bassi Denis 03 April 2007 (has links)
A polimerização adequada da resina composta está diretamente relacionada com o sucesso e longevidade das restaurações. Procurando esclarecer a efetividade das fontes de luz na fotoativação, foram realizados estudos laboratoriais, verificando a profundidade de polimerização (1, 2 e 3 mm) da resina composta Filtek Supreme 3M-ESPE, por meio de diferentes análises como: grau de conversão monomérica por espectroscopia com absorção no infravermelho (FT-IR), dureza Vickers, espectroscopia de fluorescência e análise térmica (calorimetria exploratória diferencial - DSC e termogravimetria TG), comparando-se três fontes de luz: lâmpada halógena (Optilux 501-Demetron-Kerr), LED (Lec 1000-MMOptics) e laser de argônio (INNOVA 100-Coherent). Para isso foram confeccionados em triplicata corpos-de-prova, devidamente padronizados para cada condição amostral. Os resultados de dureza Vickers e grau de conversão monomérica por FT-IR receberam tratamento estatístico pela análise de variância (ANOVA) a dois critérios, assim como as comparações múltiplas pelo teste de Tukey ao nível de significância de 5%. Para correlação dos testes de dureza e grau de conversão monomérica foi utilizado o teste de correlação de Pearson (p<0,05). O terceiro milímetro apresentou diferença estatística significante em relação ao primeiro e segundo milímetros tanto nos teste de dureza Vickers, como no grau de conversão monomérica por FT-IR. As fontes de luz apresentaram diferenças estatísticas entre elas na análise do grau de conversão, sendo que a lâmpada halógena obteve os melhores resultados, seguido do Led e laser de argônio. Não houve uma correlação positiva entre os testes de dureza e grau de conversão por FT-IR. Nos testes de espectroscopia de fluorescência e análise térmica foi possível observar uma mesma tendência de resultados verificado no teste de grau de conversão por FT-IR em relação às diferenças entre as fontes de luz e as profundidades de polimerização. Os testes mostraram-se efetivos na avaliação da profundidade de polimerização, porém o teste de dureza não se correlacionou com os demais testes e todas as fontes de luz se mostraram aptas a polimerização da resina composta até 2 mm de profundidade de acordo com os parâmetros utilizados nessa pesquisa. / The adequate polymerization of composite resin is directly related with the restoration success and longevity. Experimental studies were made to verify the efficiency of light sources in the photoactivation by the evaluation of the depth of cure (1, 2 and 3 mm) of composite resin Filtek Supreme 3M-ESPE by several methods: degree of monomeric conversion by spectroscopy Fourier transform infrared (FT-IR), Vickers hardness, fluorescence spectroscopy and thermal analysis (differential scanning calorimetry - DSC and termogravimetric analysis - TGA), comparing 3 light sources: halogen light (Optilux 501/Demetron-Kerr), LED (Lec 1000-MMOptics) and argon laser (INNOVA 100-Coherent). Samples were made in triplicate and standardized for each condition. The results of Vickers hardness and degree of conversion by FT-IR were subjected to statistical analysis using two-way analysis of variance (ANOVA) and Tukey test for multiple comparisons and the statistical significance was assumed at 5% (p<0.05), and for correlation the tests of Vickers hardness and degree of conversion were used the Pearson\' s test (p<0.05). The third millimeter presented statistical difference in relation with first and second millimeters for both tests: Vickers hardness and degree of conversion by FT-IR. The light sources presented statistical differences among them in the degree of conversion test: the halogen light had better values followed by LED and argon laser. And did not have a positive correlation between Vickers hardness and degree of conversion FT-IR. In the fluorescence spectroscopy and thermal analysis was possible to observe the same tendency in the results that they had in the degree of conversion test, in relation of difference in depth of cure and light sources. All tests showed strength in the evaluation of depth of cure, however the Vickers hardness test were not correlated with other tests and all light sources showed to able to polymerized the composite resin until 2 millimeters according to the parameters used in this research.
257

"Diferentes métodos de otimização da polimerização de resinas compostas de uso direto" / Different methods in optimizing the polymerization of direct resin composites

Ana Maria Lima Almeida 09 December 2005 (has links)
Este trabalho avaliou a influência da densidade de energia da pré-cura, e de diferentes tratamentos pós-cura na otimização das propriedades físicas (Resistência à Flexão e Dureza Knoop) de resinas compostas diretas, visando a possibilidade de indicação para restauraçoes indiretas. Foram usadas as resinas diretas Fillmagic, Concept, Glacier, Z100, Masterfill e W3D Master e as indiretas Solidex e Belleglass HP como controle. Para cada resina direta foram confeccionados 60 espécimes em barra (10x2x2mm), 30 irradiados em uma face e 30 nas duas faces (30 espécimes = 10 controle, 10 autoclave e 10 forno de luz). Para as resinas indiretas foram preparados 10 espécimes conforme processamento de seus fabricantes. 380 espécimes foram submetidos ao ensaio de resistência à flexão (Kratos). De cada condição experimental, 10 fragmentos foram usados para ensaio de microdureza Knoop (Shimadzu HMV-2). A análise de variância e o teste de Tukey demonstraram significância para resistência à flexão nos fatores Resina (p<0,001) e Tratamento (p=0,001) e na interação Resina x Tratamento (p=0,001). Para a microdureza Knoop os três fatores e as interações foram significantes: Resina (p=0,001); Face (p=0,001) Tratamento (p=0,017); Resina x Face (p=0,001); Resina x Tratamento (p=0,007); Face x Tratamento (p=0,001) e Resina x Face x Tratamento (p=0,024). A maior média de cada resina direta, independente da condição experimental, foi comparada às médias das resinas indiretas. Os resultados apontam que na resistência à flexão (Z100 = W3D = Fillmagic = Glacier) e (Z100 > Masterfill > Belleglass HP > Concept > Solidex). Na Dureza Knoop (Z100 > Belleglass HP, Fillmagic, W3D, Concept, Glacier, Masterfill e Solidex). Conclusão: as propriedades físicas (resistência à flexão e dureza Knoop) não são obstáculos na indicação de resinas compostas de uso direto para restaurações indiretas / This study evaluated the influence of pre-cure energy density, and additional post-cure treatments in optimizing the physical properties (Flexural strength and Knoop microhardness) of direct resin composites with the aim at allowing their use for indirect restorations. Direct resin composites evaluated were Fillmagic, Concept, Glacier, Z100, Masterfill and W3D Master; indirect composites were Solidex and Belleglass HP. Sixty bar-shaped specimens (10x2x2mm) were prepared for each material, so that 30 of them were light-cured by one surface and 30 on both surfaces. From the 30 specimens of each group, 10 were control, 10 were submitted to additional autoclave and 10 to light oven treatment. Ten specimens were prepared with each indirect composite following the manufactures’ recommendations. The 380 specimens were submitted to flexural strength test (Kratos universal testing machine), and values obtained at fracture were reported. After that, 10 fragments were chosen for each experimental condition and assessed for Knoop microhardness (Shimadzu HMV-2). Data were submitted to analysis of variance and Tukey’s test at p<0.05. Statistically significant differences were found among flexural strength results regarding composite materials (p<0.001), treatments (p<0.001) and interactions (composite x treatment, p<0.001). Regarding Knoop microhardness, both three factors and their interactions were also significant: composite (p<0.001), surface (p<0.001) and treatment (p<0.017), composite x surface (p<0.001), composite treatment (p<0.001), surface x treatment (p<0.001) and composite x surface x treatment (p<0.024). The highest mean value for each direct composite, regardless of the experimental condition, was compared to the mean values obtained for the indirect materials. With regard to flexural strength, comparisons point out that Z100 = W3D = Fillmagic = Glacier and Z100 > Masterfill > Belleglass HP > Concept > Solidex, whereas for Knoop microhardness Z100 > Belleglass HP, Fillmagic, W3D, Concept, Glacier, Masterfill and Solidex. Conclusion: considering the physical properties evaluated in this study, they are not an obstacle to the indication of direct composites for indirect restorations
258

Quantifying regional variation in the survival of cancer patients

Seppä, K. (Karri) 05 December 2012 (has links)
Abstract Monitoring regional variation in the survival of cancer patients is an important tool for assessing realisation of regional equity in cancer care. When regions are small or sparsely populated, the random component in the total variation across the regions becomes prominent. The broad aim of this doctoral thesis is to develop methods for assessing regional variation in the cause-specific and relative survival of cancer patients in a country and for quantifying the public health impact of the regional variation in the presence of competing hazards of death using summary measures that are interpretable also for policy-makers and other stakeholders. Methods for summarising the survival of a patient population with incomplete follow-up in terms of the mean and median survival times are proposed. A cure fraction model with two sets of random effects for regional variation is fitted to cause-specific survival data in a Bayesian framework using Markov chain Monte Carlo simulation. This hierarchical model is extended to the estimation of relative survival where the expected survival is estimated by region and considered as a random quantity. The public health impact of regional variation is quantified by the extra survival time and the number of avoidable deaths that would be gained if the patients achieved the most favourable level of relative survival. The methods proposed were applied to real data sets from the Finnish Cancer Registry. Estimates of the mean and the median survival times of colon and thyroid cancer patients, respectively, were corrected for the bias that was caused by the inherent selection of patients during the period of diagnosis with respect to their age at diagnosis. The cure fraction model allowed estimation of regional variation in cause-specific and relative survival of breast and colon cancer patients, respectively, with a parsimonious number of parameters yielding reasonable estimates also for sparsely populated hospital districts. / Tiivistelmä Syöpäpotilaiden elossaolon alueellisen vaihtelun seuraaminen on tärkeää arvioitaessa syövänhoidon oikeudenmukaista jakautumista alueittain. Kun alueet ovat pieniä tai harvaan asuttuja, alueellisen kokonaisvaihtelun satunnainen osa kasvaa merkittäväksi. Tämän väitöstutkimuksen tavoitteena on kehittää menetelmiä, joilla pystytään arvioimaan maan sisäistä alueellista vaihtelua lisäkuolleisuudessa, jonka itse syöpä potilaille aiheuttaa, ja tiivistämään alueellisen vaihtelun kansanterveydellinen merkitys mittalukuihin, jotka ottavat kilpailevan kuolleisuuden huomioon ja ovat myös päättäjien tulkittavissa. Ehdotetuilla menetelmillä voidaan potilaiden ennustetta kuvailla käyttäen elossaolo-ajan keskiarvoa ja mediaania, vaikka potilaiden seuruu olisi keskeneräinen. Potilaiden syykohtaiselle kuolleisuudelle sovitetaan bayesiläisittäin MCMC-simulaatiota hyödyntäen malli, jossa parantuneiden potilaiden osuuden kuvaamisen lisäksi alueellinen vaihtelu esitetään kahden satunnaisefektijoukon avulla. Tämä hierarkkinen malli laajennetaan suhteellisen elossaolon estimointiin, jossa potilaiden odotettu elossaolo estimoidaan alueittain ja siihen liittyvä satunnaisvaihtelu otetaan huomioon. Alueellisen vaihtelun kansanterveydellistä merkitystä mitataan elossaoloajan keskimääräisellä pidentymällä sekä vältettävien kuolemien lukumäärällä, jotka voitaisiin saavuttaa, mikäli suotuisin suhteellisen elossaolon taso saavutettaisiin kaikilla alueilla. Kehitettyjä menetelmiä käytettiin Suomen Syöpärekisterin aineistojen analysointiin. Paksusuoli- ja kilpirauhassyöpäpotilaiden elinaikojen keskiarvojen ja mediaanien estimaatit oikaistiin harhasta, joka aiheutui potilaiden luontaisesta valikoitumisesta diagnosointijakson aikana iän suhteen. Parantuneiden osuuden satunnaisefektimalli mahdollisti rintasyöpäpotilaiden syykohtaisen kuolleisuuden ja paksusuolisyöpäpotilaiden suhteellisen elossaolon kuvaamisen vähäisellä määrällä parametreja ja antoi järkeenkäyvät estimaatit myös harvaan asutuille sairaanhoitopiireille.
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Étude et simulation numérique d’un procédé de cuisson rapide pour l’élaboration de matériaux composites à matrice thermodurcissable

Xu, Chan 19 December 2013 (has links)
L’élaboration de composites en cuisson autoclave est un procédé bien maîtrisé maisles cycles de cuisson peuvent être très longs, en particulier dans le cas de préimprégnésaéronautiques. L’objectif de ce travail de thèse est d’étudier la possibilité de diminuer letemps des cycles de polymérisation pour la fabrication de composites stratifiés minces àl’aide d’un procédé de cuisson rapide. Des essais de caractérisation ont permis de définirles grandeurs thermodynamiques du préimprégné carbone/époxy qui a servi de base ànotre étude ainsi que les paramètres du modèle cinétique de la résine. Une simulationnumérique du procédé de cuisson, basée sur une modélisation des couplages desphénomènes chimiques (polymérisation de la résine), thermiques (transferts de chaleuravec prise en compte de l’exothermie de la réaction) et mécaniques (formation decontraintes et déformations résiduelles) induits par le procédé, a été développée dans lebut d’optimiser les cycles de polymérisation. La caractérisation mécanique des matériauxélaborés à partir d’un dispositif de cuisson rapide mis au point au Laboratoire a permis dedémontrer que nous n’avions pas de pertes de caractéristiques par rapport aux piècesélaborées en autoclave. / The autoclave polymerization is the bottleneck of the production flux for largepublic parts, hence the speedy polymerization process emerges to improve the productionratio. The objective is to study the possibility of reducing the cycle time of polymerizationfor the production of thin composite laminates using a fast cure process out-of-autoclave.Specific or standard chemical and mechanical characterization tests had been designed inorder to capture the expected characteristics for the model simulation and validate thesimulation results. According to the values obtained, an analysis based on the finiteelement technique is developed to simulate the speedy curing process of epoxy resincomposite. The analysis relates the cure temperature to the thermal, chemical and physicalprocesses occurring in the thin composite part during cure. Included in the analysis are theeffects such as the heat generation due to exothermic chemical reactions. For a specifiedcure cycle, the model could be used to calculate the temperature distribution, the degree ofcure of the resin inside the composite part as well as predict the residual curing stressesand the strains of the cured composite parts.Keywords :
260

An evaluation of handling and physico-mechanical properties of resin-composite materials

Al-Ahdal, Khold Yahya January 2015 (has links)
Resin composites are the most commonly used material in restorative dentistry. They have been used initially for aesthetical reasons, but afterwards were modified to be used widely for their good aesthetic and mechanical properties performance. They are classified as visco-elastic materials which are composed of inorganic fillers and organic matrix. The aim of this study was to investigate some handling properties of uncured resin composites such as stickiness, consistency and rheology. Also, to measure the degree of conversion and creep behaviour under static loading of some resin composites. In the pre-cure stage, their handling properties are very essential to achieve a successful dental restoration. Therefore, dental practitioners are very critical in choosing the resin composite restorative material. A texture analyser was used to measure the stickiness and consistency of some commercial resin composites. Also, the rheology of different commercial and model resin composites were investigated using the Bohlin Rheometer in two different temperatures (room and body temperature).Moreover, Fourier transform infrared spectroscopy (FTIR) was used to determine the degree of conversion of several bulk-fill resin composites (DC) at 4 mm depth at different periods during 24 h post-irradiation. Also, the visco-elastic stability of cured resin composites with different resin matrices was investigated under static load at different maturation times (1 h and 24 h).

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