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

Estudo clínico, patológico e detecção do papillomavírus humano no carcinoma de células escamosas de orofaringe tratados por cirurgia / Clinical and pathological study and detection of human papillomavirus in oropharynx squamous cells carcinoma submitted to surgery

Menezes, Rosilene de Melo 14 September 2016 (has links)
Introdução: O câncer de orofaringe representa 10 a 12 % entre todos os tumores malignos do trato aero digestivo superior com incidência crescente nos Estados Unidos e Europa. O Papillomavírus humano (HPV) está associado aos tumores de orofaringe em até 63%, promovendo uma evolução e prognóstico melhor. Objetivo: Descrever a prevalência do HPV em carcinomas de células escamosas de orofaringe tratados por cirurgia. Analisar a associação entre a presença do HPV e as características demográficas, clínicas, patológicas e terapêuticas. Avaliar a importância da presença do HPV na sobrevida livre de doença e sobrevida global. Método: Pesquisamos a presença do Papillomavirus humano, por PCR, no anátomo patológico. A descrição da amostra foi realizada através de média, frequência absoluta e relativa. Foi estimada a prevalência do HPV e seu respectivo intervalo de 95% de confiança. A análise da associação entre a presença de HPV e as características demográficas, clínicas e patológicas, foi feita pelo teste de associação pelo quiquadrado. A análise da sobrevida livre de doença e sobrevida global foi feita pelo estimador produto limite de Kaplan-Meier e modelos de risco proporcionais de Cox. Resultados: Os pacientes apresentavam idade variando de 34 a 78 anos, com uma média de 56,9 anos. Apenas 10 mulheres no estudo, totalizando com 76 homens. A maioria dos pacientes eram brancos (83,7%). Até 6 meses foi o tempo que a maioria dos pacientes apresentaram como início dos sintomas (69,0%). O sintoma mais comum foi a odinofagia (38,4%). A amígadala foi a localização mais frequente (69,8%). Quanto ao estádio clínico, o III e o IV apresentavam a maior frequência (71,4%). Forma realizadas cirurgias amplas como as bucofaringectomias em 76 pacientes (88,4%). O esvaziamento cervical ipsilateral foi realizado em 81 pacientes (94,2%) e no contralateral em apenas 21 (24,4%). A prevalência do HPV foi de 57%, e o tipo mais comum foi o 16, em 83,6%. A única associação estatisticamente significativa entre as variáveis do estudo com o HPV, foi o tabagismo, onde todos os não fumantes apresentavam HPV. As taxas de sobrevida livre de doença foram 73,9%, 65,9 e 57,9% respectivamente para 12, 24 e 60 meses. Houve diferença estatisticamente significativa com piores taxas, para idade menor que 55 anos e margens comprometidas. A presença do HPV não influenciou a sobrevida livre de doença, nem a sobrevida global. As taxas de sobrevida global foram 75,6%, 54,7% e 43,0%, respectivamente aos 12, 24 e 60 meses. Houveram piores taxas para o paciente etilista e com recidiva.Conclusão:A presença do HPV não se mostrou importante, como fator prognóstico, nessa série cirúrgica se o paciente for etilista e ou tabagista / Introduction:Oropharynx cancer is considered to enact approximately 10 to 12% of the cases among all malignant tumors from the upper aero digestive tract showing significant growth in its frequency rate in The United States and Europe. Human papillomavirus (HPV) is associated to oropharynx cancer in up to 63% of the cases, promoting better evolution and prognostic.Objective:Describe the prevalence of the HPV in oropharynx squamous cells carcinoma submitted to surgery. Investigate the association between HPV presence and the demographic, clinical, pathologic and therapeutic features. Estimate the importance of the HPV existence on the diseasefree survival and overall survival. Material andMethods: The existence of Human papillomavirus was studied through the use of PCR. The sample account was conducted through average, absolute and relative frequency. It has been estimated the prevalence of HPV and its corresponding 95% confidence interval. The association analysis between the presence of HPV and the demographic, clinical and pathological features was completed by the Qui-square association test. The disease-free survival timeline and the overall survival were estimated using the product limit estimator Kaplan-Meier and Cox proportional hazards model. Results: The studied patients were aged between 34 and 78, showing an average of 56.9 years of age. There were only 10 women in the study, thus presenting 76 men. Most of the patients were white (83.7%). It has been ascertained that 69.0% of the patients presented the symptoms onset up to the sixth month of the disease. The most common symptom among 38.4% of the cases was odinophagy. In regards to the tumor location 69.8% were found in the amygdala.Clinical stagings III and IV were found to be the ones with greater representation among patients (71.4%). Extensive surgeries such as bucopharyngectomy were performed in 76 patients (88.4%). In order to treat ipsilateral neck 81 patients underwent neck dissection (94.2%). Contralateral neck dissection was applied in 21 patients (24.4%). The prevalence of HPV was of 57%, and the most common type was 16, present in 83.6% of the cases. It was possible to notice smoking as the only statistically significant association, which showed all nonsmoking having HPV. The disease-free survival rates were of 73.9%, 65.9% and 57.9% to 12, 24 and 60 months respectively. The study has shown significant statistical difference with worse rates, to the ones under 55 years of age and presenting compromised margins. HPV presence did not influence the disease-free survival timeline, or the overall survival. The overall survival rates were of 75.6%, 54.7% and 43.0% to 12, 24 and 60 months respectively. Worse rates were found in alcoholic patients as well as in relapse cases. Conclusion: In these surgical series, HPV existence was not identified as an important prognosis factor when considering smokers and/or alcoholic patients
32

Comparação de resultados de uma coorte sob as abordagens prospectiva e histórica: amamentação no primeiro ano de vida / Comparison between results of a cohort under prospective and historical approaches: breastfeeding in the first year of age

Alencar, Gizelton Pereira 23 May 2003 (has links)
Objetivo. Uma coorte de crianças foi observada sob duas abordagens: coorte prospectiva e coorte retrospectiva (histórica) e o objetivo foi comparar as estimativas da função de riscos do modelo de Cox entre as duas abordagens e a mesma comparação com o modelo complemento log-log. Além disso, comparar as estimativas da função de riscos pelos modelos de Cox e complemento log-log para cada uma das abordagens, separadamente. Métodos. Quando se estuda o tempo de sobrevida da amamentação sem as covariáveis, foram obtidas as estimativas pela técnica atuarial e modelo complemento log-log da informação retrospectiva e a técnica de Kaplan-Meier para a informação prospectiva. Os modelos de Cox e complemento log-log foram utilizados para estimar a razão de riscos (HR) com covariáveis para as duas abordagens. Resultados. Sem as covariáveis, a comparação entre as duas abordagens mostrou que as estimativas de S(t) pela informação retrospectiva estão um pouco defasadas em relação à medida prospectiva. Com as covariáveis, os resultados dos modelos de Cox e complemento log-log são semelhantes tanto para os dados prospectivos quanto para os retrospectivos. Foram semelhantes, também, os resultados de um mesmo modelo para cada uma das fontes de informação. Conclusões. Em geral, as estimativas foram bastante próximas em quaisquer das comparações. Somente a variável hábito de fumar da mãe durante a gravidez permaneceu nos modelos finais para todas as técnicas utilizadas, com estimativas próximas, reforçando semelhança entre as várias abordagens. / Objective. A cohort of children was observed under two approaches: prospective cohort and retrospective (historical) cohort and the objective was to compare the estimates of the hazard ratio from Cox model between the two approaches and do the same comparison using the complementary log-log model. Moreover, to compare the estimates of the hazard ratio from the two models to each one of the approaches, separately. Methods. When the survival time for breastfeeding is studied without the covariates, the comparison between the results of actuarial technique and the complementary log-log model has been made for the recorded information. The Kaplan-Meier technique has been used with the daily notebook measures. The Cox and complementary log-log models can estimate the risk rate of covariates categories to both approaches. Results. Without the covariates, the comparison between the two information resources showed that retrospective measures give lower estimates than that from the prospective measures. With covariates, the estimates are not so different and led to the same results. Conclusions. The estimates of each one of the comparisons were too close. Just the variable mothers smoking during the pregnancy stayed in the final models for every techniques used, with close estimates, reinforcing likeness between the several approaches.
33

Vad är krig? : En idéanalys av krigets aktörer, mål och medel

Malmström, Malin January 2012 (has links)
War has for all through the years adopted various guises and been performed by various actors for a wide variety of destination. But what is really a war? Why is war fought? How is war fought? By whom is war fought? Machiavelli, Clausewitz, Kaplan, Kaldor, Creveld and Krulak are just a few among others who have made valiant attempts to explain war and its nature. What did they find? This essay maps out their studies in the hope of finding some kind of continuity that can give a clearer picture of what war really is. It is important to point out; the goal is not to try to make a definition of war, but merely an attempt to find some kind of continuity. The study finds that as society develops, bridges get built and contracts are signed, everything falls apart at some point and you can  never be sure that something as complex as a war to retain some form of continuity, if any – it would be the power it contains, but barely it.
34

Técnicas não-paramétricas e paramétricas usadas na análise de sobrevivência de Chrysoperla externa (Neuroptera: Chrysopidae) / Non-Parametric and Parametric Techniques used in the survival analysis of Chrysoperla externa (Neuroptera: Chrysopidae)

Miranda, Marconi Silva 13 March 2012 (has links)
Made available in DSpace on 2015-03-26T13:32:15Z (GMT). No. of bitstreams: 1 texto completo.pdf: 512216 bytes, checksum: fd4223913c0ad60bce75a563695255ec (MD5) Previous issue date: 2012-03-13 / In survival analysis, the response variable is the time of occurrence of an event of interest, denominated failure time. Another characteristic of the survival analysis is to incorporate to the study incomplete sample data, in which for a determined reason the occurrence of the event was not verified, being these data defined as censured. The objective of this paper was to compare the use of the parametric and non-parametric techniques to estimate the survival time of C. externa (Neuroptera: Chrysopidae), predator insect which feed on other insects as well as mite, under the effect of three commercial products nim-based: Neempro (10 g of azadirachtina L-1), Organic neem (3,3 g of Azadirachtina L-1) and Natuneem (1,5 g of azadirachtina L-1). With this objective the survival functions for the different concentrations of each product, through the non-parametric method of Kaplan-Meier were estimated and compared by the logrank test and by parametric techniques, using the Weibull and log-normal exponential tests. Besides that, a study in order to select the most parsimonious model was done, using for that the likelihood ratio test (LRT) as well as the Akaike information criterion (AIC). The estimates of the selected parametric model were used to determine the survival functions in the concentrations of the three products, with the purpose of comparing with the nonparametric estimator Kaplan-Meier. Once the best model was defined the median survival time of C. externa was calculated in the tested concentrations of the products. Taking into consideration the conditions described in this experiment, one can conclude that the concentrations of the nim-based products have influence in the survival of C. externa. The higher the concentration of the used products, the lower was the survival time and among the evaluated products, Neempro was the one which presented the least lethal to the natural predator. / Em análise de sobrevivência, a variável resposta é o tempo de ocorrência de um evento de interesse, denominado tempo de falha. Outra característica da análise de sobrevivência é incorporar ao estudo dados amostrais incompletos, que por algum motivo a ocorrência do evento não foi verificada, dados estes definidos como censurados. O objetivo deste trabalho foi comparar o uso das técnicas paramétricas e não-paramétricas para estimar o tempo de sobrevivência de C. externa (Neuroptera: Chrysopidae), inseto predador que se alimenta de outros insetos e ácaros, sob efeito de três produtos comerciais à base de nim: Neempro (10 g de azadirachtina L-1), Organic neem (3,3 g de Azadirachtina L-1) e Natuneem (1,5 g de azadiractina L-1). Com esse objetivo foram estimadas as funções de sobrevivência para as diferentes concentrações de cada produto, por meio do método não-paramétrico de Kaplan-Meier, e comparadas pelo teste logrank e por meio das técnicas paramétricas, utilizando os modelos exponencial, de Weibull e log-normal. Foi realizado ainda, um estudo com a finalidade de selecionar o modelo mais parcimonioso, utilizando para isto o teste da razão de verossimilhança (TRV) e o critério de informação de Akaike (AIC). As estimativas do modelo paramétrico selecionado foram usadas para determinar as funções de sobrevivência nas concentrações dos três produtos, com o objetivo de comparar com o estimador não-paramétrico de Kaplan-Meier. Definido o melhor modelo foi calculado o tempo mediano de sobrevivência do C. externa nas concentrações testadas dos produtos. Levando em consideração as condições descritas neste experimento, pode-se concluir que as concentrações dos produtos a base de nim possuem influencia na sobrevivência de C. externa. Quanto maior foi a concentração dos produtos utilizados, menor foi o tempo de sobrevivência e entre os produtos avaliados o Neempro foi o que apresentou ser o menos letal ao predador natural.
35

Estudo da idade da vaca ao último parto para avaliar longevidade em rebanhos da raça nelore por análise de sobrevivência

Caetano, Sabrina Luzia [UNESP] 05 July 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-05Bitstream added on 2014-06-13T18:43:23Z : No. of bitstreams: 1 caetano_sl_dr_jabo.pdf: 775583 bytes, checksum: a57f6e271b7d34656d680987f933ba7d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / No Brasil, existem poucos estudos sobre longevidade de vacas de corte, principalmente utilizando ferramentas de análise de sobrevivência na estimação de parâmetros genéticos. Todavia, os critérios para avaliar esta característica são vários, tal que em alguns destes nem todos os registros das vacas nos rebanhos podem ser levados em consideração, devido à metodologia de análise utilizada. Uma variável que é de fácil mensuração e já faz parte da maioria dos controles zootécnicos das fazendas é a idade da vaca ao último parto (IVUP). Neste trabalho, objetivo foi avaliar a longevidade das vacas nos rebanhos utilizando a variável IVUP, por meio da metodologia de análise de sobrevivência. Esta variável foi utilizada mediante um critério para analisar a longevidade produtiva de vacas nos rebanhos. O critério adotado foi a diferença entre a data em relação ao último parto de cada vaca e a data do último parto de cada fazenda. Se esta diferença foi superior a 36 meses, a vaca falhou e foi considerada descartada. Caso contrário, esta vaca foi censurada, indicando que esta ainda poderia ter futuras parições. O critério de 36 meses foi proposto por ser período suficiente para a ocorrência de um novo parto. A metodologia de análise de sobrevivência foi utilizada por considerar dados censurados e não censurados. As variáveis: estação e ano de nascimento de cada vaca, a fazenda e a idade ao primeiro parto foram utilizadas para as análises da variável IVUP. Um estudo prévio por meio de curvas de Kaplan-Meier e o modelo de Cox, utilizando a distribuição gama para os touros, desconsiderando o parentesco entre eles, foram realizados. O software Survival Kit foi empregado para estimação dos parâmetros genéticos, levando em consideração o parentesco entre os animais. Verificou-se que a IVUP apresentou herdabilidade de 0,25, e que seu uso permite avaliar a... / In Brazil, there are few studies about stayability, especially using tools of survival analysis in the estimation of breeding values and heritability. The criteria for evaluating this characteristic are different, such that in some of these not all information in the herds of cows can be taken into consideration, because the method of analysis used. In addition, the definitions that consider the date of disposal of the animal affect the use of information obtained in practice, because until the cows come out of the flock may take years, thus the evaluation of their parents is impaired, since the goal is selection. A variable that is easy to measure and is already part of most controls husbandry farms are cow age at last birth (IVUP). This variable was used by one criterion to analyze the productive longevity of cows in herds. The criterion was the difference between the date from the last delivery date of each cow and the last part of each farm. If this difference was more than 36 months, the cow was considered failed and discarded. Otherwise, this cow was censored, indicating that this could still have further parities. The criterion of 36 months was proposed to be sufficient time for the occurrence of a new birth. The methodology of survival analysis was used. The variables season and year of birth of each cow, farm and age at first birth were used for analysis of variable IVUP. The objective of this study was to evaluate the performance of the variable IVUP through estimates of genetic and fixed effect, to study the longevity of cows in the herd. A previous study by Kaplan-Meier and Cox model using the gamma distribution for the bulls, disregarding the relationship between them, were performed. The Survival Kit software was used to estimate the genetic parameters, taking into account the relationship between the animals. It was found that the heritability of 0.25 for IVUP ... (Complete abstract click electronic access below)
36

Avalia??o gen?tica da efici?ncia reprodutiva em vacas pardo-su??as por meio da an?lise de sobreviv?ncia

Guedes, Deborah Galv?o Peixoto 20 February 2014 (has links)
Made available in DSpace on 2014-12-17T15:34:49Z (GMT). No. of bitstreams: 1 DeborahGPG_DISSERT.pdf: 1421770 bytes, checksum: da1c0ade32fb8610306243b0cf52f13d (MD5) Previous issue date: 2014-02-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Among the traits of economic importance to dairy cattle livestock those related to sexual precocity and longevity of the herd are essential to the success of the activity, because the stayability time of a cow in a herd is determined by their productive and reproductive lives. In Brazil, there are few studies about the reproductive efficiency of Swiss-Brown cows and no study was found using the methodology of survival analysis applied to this breed. Thus, in the first chapter of this study, the age at first calving from Swiss-Brown heifers was analyzed as the time until the event by the nonparametric method of Kaplan-Meier and the gamma shared frailty model, under the survival analysis methodology. Survival and hazard rate curves associated with this event were estimated and identified the influence of covariates on such time. The mean and median times at the first calving were 987.77 and 1,003 days, respectively, and significant covariates by the Log-Rank test, through Kaplan-Meier analysis, were birth season, calving year, sire (cow s father) and calving season. In the analysis by frailty model, the breeding values and the frailties of the sires (fathers) for the calving were predicted modeling the risk function of each cow as a function of the birth season as fixed covariate and sire as random covariate. The frailty followed the gamma distribution. Sires with high and positive breeding values possess high frailties, what means shorter survival time of their daughters to the event, i.e., reduction in the age at first calving of them. The second chapter aimed to evaluate the longevity of dairy cows using the nonparametric Kaplan-Meier and the Cox and Weibull proportional hazards models. It were simulated 10,000 records of the longevity trait from Brown-Swiss cows involving their respective times until the occurrence of five consecutive calvings (event), considered here as typical of a long-lived cow. The covariates considered in the database were age at first calving, herd and sire (cow s father). All covariates had influence on the longevity of cows by Log-Rank and Wilcoxon tests. The mean and median times to the occurrence of the event were 2,436.285 and 2,437 days, respectively. Sires that have higher breeding values also have a greater risk of that their daughters reach the five consecutive calvings until 84 months / Dentre as caracter?sticas de import?ncia econ?mica para a pecu?ria leiteira aquelas relacionadas com a precocidade sexual e a longevidade do rebanho s?o determinantes para o sucesso da atividade, uma vez que o tempo de perman?ncia de uma vaca num rebanho ? determinado por suas vidas produtiva e reprodutiva. No Brasil, existem poucos estudos sobre a efici?ncia reprodutiva de vacas Pardo-Su??as e n?o foi encontrado nenhum estudo abordando o uso da metodologia de an?lise de sobreviv?ncia aplicada a esta ra?a. Assim, no primeiro cap?tulo deste trabalho, a idade ao primeiro parto de novilhas Pardo-Su??as foi analisada como o tempo at? o evento por meio do m?todo n?o-param?trico de Kaplan-Meier e do modelo de fragilidade compartilhado gama, sob a metodologia de an?lise de sobreviv?ncia. Foram estimadas curvas de sobreviv?ncia e de taxa de risco associadas com este evento e verificada a influ?ncia das covari?veis consideradas sobre o tempo. Os tempos m?dio e mediano ao primeiro parto foram 987,77 e 1.003 dias, respectivamente; e as covari?veis significativas pelo teste de Log-Rank, na an?lise por Kaplan-Meier, foram esta??o de nascimento, ano de parto, touro (pai da vaca) e esta??o de parto. Na an?lise pelo modelo de fragilidade, foram preditos os valores gen?ticos e as fragilidades dos touros (pais) para o parto, modelando-se a fun??o de risco de cada vaca em fun??o da covari?vel fixa esta??o de nascimento e da covari?vel aleat?ria touro. A fragilidade seguiu a distribui??o gama. Touros com valores gen?ticos positivos e altos possuem fragilidades altas, o que significa menor tempo de sobreviv?ncia de suas filhas ao evento, ou seja, redu??o na idade ao primeiro parto delas. O segundo cap?tulo teve como objetivo avaliar a longevidade de vacas leiteiras utilizando o estimador n?o-param?trico de Kaplan-Meier e os modelos de riscos proporcionais de Weibull e de Cox. Foram simulados 10.000 registros da caracter?stica longevidade de f?meas Pardo-Su??as denotando seus respectivos tempos at? a ocorr?ncia de cinco partos consecutivos (evento), considerados aqui como t?picos de uma vaca longeva. As covari?veis consideradas no banco de dados foram a idade da vaca ao primeiro parto, o rebanho e o pai da vaca. Todas as covari?veis exerceram influ?ncia sobre a longevidade das vacas de acordo com os testes de Log-Rank e Wilcoxon. Os tempos m?dio e mediano para a ocorr?ncia do evento foram de 2.436,285 e 2.437 dias. Touros com maior valor gen?tico tamb?m possuem um maior risco de que as suas filhas alcancem os cinco partos aos 84 meses
37

Comparação de resultados de uma coorte sob as abordagens prospectiva e histórica: amamentação no primeiro ano de vida / Comparison between results of a cohort under prospective and historical approaches: breastfeeding in the first year of age

Gizelton Pereira Alencar 23 May 2003 (has links)
Objetivo. Uma coorte de crianças foi observada sob duas abordagens: coorte prospectiva e coorte retrospectiva (histórica) e o objetivo foi comparar as estimativas da função de riscos do modelo de Cox entre as duas abordagens e a mesma comparação com o modelo complemento log-log. Além disso, comparar as estimativas da função de riscos pelos modelos de Cox e complemento log-log para cada uma das abordagens, separadamente. Métodos. Quando se estuda o tempo de sobrevida da amamentação sem as covariáveis, foram obtidas as estimativas pela técnica atuarial e modelo complemento log-log da informação retrospectiva e a técnica de Kaplan-Meier para a informação prospectiva. Os modelos de Cox e complemento log-log foram utilizados para estimar a razão de riscos (HR) com covariáveis para as duas abordagens. Resultados. Sem as covariáveis, a comparação entre as duas abordagens mostrou que as estimativas de S(t) pela informação retrospectiva estão um pouco defasadas em relação à medida prospectiva. Com as covariáveis, os resultados dos modelos de Cox e complemento log-log são semelhantes tanto para os dados prospectivos quanto para os retrospectivos. Foram semelhantes, também, os resultados de um mesmo modelo para cada uma das fontes de informação. Conclusões. Em geral, as estimativas foram bastante próximas em quaisquer das comparações. Somente a variável hábito de fumar da mãe durante a gravidez permaneceu nos modelos finais para todas as técnicas utilizadas, com estimativas próximas, reforçando semelhança entre as várias abordagens. / Objective. A cohort of children was observed under two approaches: prospective cohort and retrospective (historical) cohort and the objective was to compare the estimates of the hazard ratio from Cox model between the two approaches and do the same comparison using the complementary log-log model. Moreover, to compare the estimates of the hazard ratio from the two models to each one of the approaches, separately. Methods. When the survival time for breastfeeding is studied without the covariates, the comparison between the results of actuarial technique and the complementary log-log model has been made for the recorded information. The Kaplan-Meier technique has been used with the daily notebook measures. The Cox and complementary log-log models can estimate the risk rate of covariates categories to both approaches. Results. Without the covariates, the comparison between the two information resources showed that retrospective measures give lower estimates than that from the prospective measures. With covariates, the estimates are not so different and led to the same results. Conclusions. The estimates of each one of the comparisons were too close. Just the variable mothers smoking during the pregnancy stayed in the final models for every techniques used, with close estimates, reinforcing likeness between the several approaches.
38

Estudo clínico, patológico e detecção do papillomavírus humano no carcinoma de células escamosas de orofaringe tratados por cirurgia / Clinical and pathological study and detection of human papillomavirus in oropharynx squamous cells carcinoma submitted to surgery

Rosilene de Melo Menezes 14 September 2016 (has links)
Introdução: O câncer de orofaringe representa 10 a 12 % entre todos os tumores malignos do trato aero digestivo superior com incidência crescente nos Estados Unidos e Europa. O Papillomavírus humano (HPV) está associado aos tumores de orofaringe em até 63%, promovendo uma evolução e prognóstico melhor. Objetivo: Descrever a prevalência do HPV em carcinomas de células escamosas de orofaringe tratados por cirurgia. Analisar a associação entre a presença do HPV e as características demográficas, clínicas, patológicas e terapêuticas. Avaliar a importância da presença do HPV na sobrevida livre de doença e sobrevida global. Método: Pesquisamos a presença do Papillomavirus humano, por PCR, no anátomo patológico. A descrição da amostra foi realizada através de média, frequência absoluta e relativa. Foi estimada a prevalência do HPV e seu respectivo intervalo de 95% de confiança. A análise da associação entre a presença de HPV e as características demográficas, clínicas e patológicas, foi feita pelo teste de associação pelo quiquadrado. A análise da sobrevida livre de doença e sobrevida global foi feita pelo estimador produto limite de Kaplan-Meier e modelos de risco proporcionais de Cox. Resultados: Os pacientes apresentavam idade variando de 34 a 78 anos, com uma média de 56,9 anos. Apenas 10 mulheres no estudo, totalizando com 76 homens. A maioria dos pacientes eram brancos (83,7%). Até 6 meses foi o tempo que a maioria dos pacientes apresentaram como início dos sintomas (69,0%). O sintoma mais comum foi a odinofagia (38,4%). A amígadala foi a localização mais frequente (69,8%). Quanto ao estádio clínico, o III e o IV apresentavam a maior frequência (71,4%). Forma realizadas cirurgias amplas como as bucofaringectomias em 76 pacientes (88,4%). O esvaziamento cervical ipsilateral foi realizado em 81 pacientes (94,2%) e no contralateral em apenas 21 (24,4%). A prevalência do HPV foi de 57%, e o tipo mais comum foi o 16, em 83,6%. A única associação estatisticamente significativa entre as variáveis do estudo com o HPV, foi o tabagismo, onde todos os não fumantes apresentavam HPV. As taxas de sobrevida livre de doença foram 73,9%, 65,9 e 57,9% respectivamente para 12, 24 e 60 meses. Houve diferença estatisticamente significativa com piores taxas, para idade menor que 55 anos e margens comprometidas. A presença do HPV não influenciou a sobrevida livre de doença, nem a sobrevida global. As taxas de sobrevida global foram 75,6%, 54,7% e 43,0%, respectivamente aos 12, 24 e 60 meses. Houveram piores taxas para o paciente etilista e com recidiva.Conclusão:A presença do HPV não se mostrou importante, como fator prognóstico, nessa série cirúrgica se o paciente for etilista e ou tabagista / Introduction:Oropharynx cancer is considered to enact approximately 10 to 12% of the cases among all malignant tumors from the upper aero digestive tract showing significant growth in its frequency rate in The United States and Europe. Human papillomavirus (HPV) is associated to oropharynx cancer in up to 63% of the cases, promoting better evolution and prognostic.Objective:Describe the prevalence of the HPV in oropharynx squamous cells carcinoma submitted to surgery. Investigate the association between HPV presence and the demographic, clinical, pathologic and therapeutic features. Estimate the importance of the HPV existence on the diseasefree survival and overall survival. Material andMethods: The existence of Human papillomavirus was studied through the use of PCR. The sample account was conducted through average, absolute and relative frequency. It has been estimated the prevalence of HPV and its corresponding 95% confidence interval. The association analysis between the presence of HPV and the demographic, clinical and pathological features was completed by the Qui-square association test. The disease-free survival timeline and the overall survival were estimated using the product limit estimator Kaplan-Meier and Cox proportional hazards model. Results: The studied patients were aged between 34 and 78, showing an average of 56.9 years of age. There were only 10 women in the study, thus presenting 76 men. Most of the patients were white (83.7%). It has been ascertained that 69.0% of the patients presented the symptoms onset up to the sixth month of the disease. The most common symptom among 38.4% of the cases was odinophagy. In regards to the tumor location 69.8% were found in the amygdala.Clinical stagings III and IV were found to be the ones with greater representation among patients (71.4%). Extensive surgeries such as bucopharyngectomy were performed in 76 patients (88.4%). In order to treat ipsilateral neck 81 patients underwent neck dissection (94.2%). Contralateral neck dissection was applied in 21 patients (24.4%). The prevalence of HPV was of 57%, and the most common type was 16, present in 83.6% of the cases. It was possible to notice smoking as the only statistically significant association, which showed all nonsmoking having HPV. The disease-free survival rates were of 73.9%, 65.9% and 57.9% to 12, 24 and 60 months respectively. The study has shown significant statistical difference with worse rates, to the ones under 55 years of age and presenting compromised margins. HPV presence did not influence the disease-free survival timeline, or the overall survival. The overall survival rates were of 75.6%, 54.7% and 43.0% to 12, 24 and 60 months respectively. Worse rates were found in alcoholic patients as well as in relapse cases. Conclusion: In these surgical series, HPV existence was not identified as an important prognosis factor when considering smokers and/or alcoholic patients
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Laufradschaufeln und Saugkrümmer. Die Plansammlung des Erfinders Viktor Kaplan

Camilleri, Carla, Herles, Karin 13 June 2022 (has links)
Das Archiv des Technischen Museums Wien verwahrt den umfangreichen Nachlass von Viktor Kaplan (1876-1934). Er gehört zu den bedeutendsten österreichischen Ingenieuren des 20. Jahrhunderts und ist der Erfinder der nach ihm benannten Turbine. Die vor rund 100 Jahren entwickelte Kaplan- Turbine ist bis heute weltweit in Verwendung. Sie hat den Einsatz von Wasserkraft als erneuerbare Energie wesentlich erweitert. Der Nachlass von Viktor Kaplan wurde 2014 in das österreichische Dokumentenregister der UNESCO aufgenommen und zählt damit zu jenen Beständen, die von herausragender Bedeutung für das kulturelle Gedächtnis Österreichs sind. Rund 1.400 technische Zeichnungen aus dem Nachlass des Technikers werden aktuell im Zuge eines mehrjährigen Projekts konservatorisch versorgt und wissenschaftlich bearbeitet. Im Rahmen des Vortrages wird das aufwändige Konservierungsprojekt sowie die wissenschaftliche Erschließung des Bestandes präsentiert. Der Bestand steht für Recherchen im Online-Katalog zur Verfügung unter: https://www.technischesmuseum.at/museum/online- sammlung#sammlung/ui//browseExhibition/14622 / The archive of the Vienna Museum of Technology holds the extensive estate of Viktor Kaplan (1876-1934). He is one of the most important Austrian engineers of the 20th century and the inventor of the turbine named after him. The Kaplan turbine, developed around 100 years ago, is still in use worldwide today. It has significantly expanded the use of hydropower as a renewable energy source. Viktor Kaplan's estate was included in UNESCO's „Memory of Austria“ in 2014, making it one of those holdings that are of outstanding importance to Austria's cultural memory. Around 1,400 technical drawings from the estate of the technician are currently being conserved and scientifically processed in the course of a project lasting several years. The lecture will present the complex conservation project and the scientific indexing of the collection. The collection is available for research in the online catalogue at: https://www.technischesmuseum.at/museum/online- sammlung#sammlung/ui//browseExhibition/14622
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Optimization of Kaplan turbines for frequency regulation in hybrid hydropower plants

Narkhede, Nayan January 2022 (has links)
The increasing penetration of variable renewable energy sources in the Nordic Power System is causing frequency quality degradation and has increased the importance of primary frequency control provided by hydropower plants. Hydropower is the world’s largest renewable energy source. Its reliability, controllability and dispatchability along with its large storage volume makes it the most important source for providing frequency regulation in the Nordic Power System. Many hydropower plants offering regulating power have Kaplan turbines which have complex mechanical systems. Furthermore, the frequent and fast mechanical movements of the Kaplan turbines, providing frequency regulation causes the problem of wear and tear in the guide vanes and runner blades of the turbines. Kaplan turbines are suitable for stable operation.   To mitigate this problem, a solution of hybrid hydropower plants combined with  battery energy storage systems is investigated in this thesis, where batteries can take care of fast frequency deviations, allowing for a more stable operation of the turbines. The analysis is based on the FCR-N service offered by hydropower plants, because FCR-N is identified as one of the services that requires very fast changes in the output power of the hydropower plant. Modelling and simulation, data analysis and on-site measurement are adopted as main study methods in this thesis.  The simulation models of a hydropower plant and a hybrid hydropower plant are developed for the analysis. The simulation model of the hydropower plant is validated using data from a typical Swedish hydropower plant. Quantification of wear and tear is the main focus of the study. The performance of the hydropower plant and hybrid hydropower plant are compared in terms of wear and tear of turbines, speed of the response of plants to frequency deviations and number of directional changes during the mechanical movements of the turbine. Finally, it is concluded that, addition of batteries with hydropower plants will reduce wear and tear of the turbines as well as improve the frequency quality in the Nordic Power System.

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