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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.
261

Instilação nasal de LPS ou suco gástrico como fator exacerbador da inflamação pulmonar ocasionada pela isquemia e reperfusão intestinal em camundongos. / Intranasal instillation of LPS or gastric juice as an exacerbating factor of lung inflammation induced by intestinal ischemia and reperfusion.

Soares, Alexandre Learth 03 July 2009 (has links)
A isquemia e reperfusão intestinal (I/R-i) é relevante fator para o desenvolvimento da síndrome do desconforto respiratório agudo (SDRA). A lesão tecidual decorrente da I/R-i pode ser local e em órgãos distante do sitio isquêmico, notadamente o pulmão. Indivíduos submetidos à isquemia intestinal ao tornarem-se vulneráveis, desenvolvem resposta exacerbada a estímulos inflamatórios secundários constituindo assim a percepção de lesão decorrente de uma dupla agressão. Neste estudo desenvolvemos modelo murino de dupla agressão pulmonar ocasionada pela I/R-i seguida de estímulo da instilação nasal de LPS ou de suco gástrico (SG). A fase de caracterização do modelo de I/R-i revelou aumento de IL-6, G-CSF, KC, IP-10 e MCP-1, mas não de TNF-a no soro e em homogeneizados de pulmão e intestino. Anticorpos anti TNF-a e o etanercepte falharam em inibir o aumento de MPO pulmonar e intestinal após a I/R-i. A instilação nasal de LPS após a I/R-i aumentou a atividade pulmonar de MPO e exacerbou a permeabilidade vascular pulmonar. Neste caso, aminoguanidina ou a vimblastina reverterem o aumento da permeabilidade vascular, sugerindo a participação conjunta de neutrófilos e óxido nítrico no processo lesivo causado pela dupla agressão. A instilação nasal de SG induziu aumento inicial (2h) de MPO pulmonar seguido de influxo de neutrófilos (24h) para o espaço alveolar. Tal processo foi acompanhado por expressão inicial e transiente de TNF-a no LBA e contrabalanceada por IL-10. A resposta inflamatória aumentada de camundongos IL-10 KO à instilação de suco gástrico mostra o papel fundamental desta citocina do controle da inflamação. O rolipram ou o composto PKF 241-466 (inibidores de TNF-a) reduziram a inflamação pulmonar induzida pelo SG. A instilação de SG após a I/R-i (I/R-i +SG) exacerbou o aumento da permeabilidade vascular pulmonar. Os dados apresentados sugerem que a exposição do organismo ao trauma intestinal torna o pulmão suscetível a um estímulo secundário como o LPS e o suco gástrico. Visto a gama de estímulos inflamatórios a que indivíduos internados em unidades de terapia intensiva podem ser submetidos, os resultados deste estudo podem contribuir para a compreensão dos mecanismos reguladores do recrutamento de neutrófilos e geração de mediadores inflamatórios na síndrome do desconforto respiratório agudo. / Intestinal ischemia and reperfusion (I/R) is implicated as a prime initiating event in the development of systemic inflammatory syndrome and Acute Respiratory Distress Syndrome (ARDS). Several studies pointed the possibility of massive systemic inflammatory events rendering the lungs more susceptible to an exacerbated inflammatory response, the so called two-hit hypothesis. In this way, minor local inflammatory stimuli could be a trigger for ARDS. In this study we investigated the effects of low-dose LPS or gastric juice (GJ) administered by nasal instillation to mice previously submitted to intestinal I/R. Our data showed that i-I/R alone induced histological signs of edema in lung as well as an increase of lung MPO activity and IL-6, G-CSF, KC, IP-10 and MCP-1 levels. Nasal instillation of LPS following i-I/R increased lung MPO activity and exacerbated lung vascular permeability. In this case, aminoguanidine or vinblastine blocked the increase of vascular permeability, suggesting the role of neutrophils and nitric oxide in injury induced by the two-hit stimuli. Instillation of GJ induced an initial (2h) increase of lung MPO followed by the influx of neutrophils (24h) to the alveolar space. Such process was followed by the transient expression of TNF-a in BAL and balanced by IL-10. The exacerbated inflammatory response of IL-10 KO mice to GJ instillation shows the importance of this cytokine in the control of the inflammation in such model. Treatment with rolipram or PKF 241-466 compound (TNF-a inhibitors) reduced lung inflammation induced by GJ. Nasal instillation of GJ after i-I/R exacerbated the increase in lung vascular permeability. The data shown suggest that the exposition of the organism to mesenteric trauma primes the host organism to a secondary inflammatory stimulus such as LPS or gastric juice. Considering the possible multiple insults to lung to which patients in intensive care units are submitted, the results of this study might contribute to the understanding of the regulatory mechanisms of neutrophils and generation of inflammatory mediators in the context of ARDS.
262

Análise de resultados de Punção Aspirativa por Agulha Fina (PAAF) de nódulos tireoidianos e correlação com tireoidectomias em população do interior do estado de São Paulo, Brasil / Analysis of results of Fine Needle Aspiration (FNA) of thyroid nodules and correlation with thyroidectomies in a population of the northeastern region of the state of São Paulo, Brazil

Ana Paula Figueiredo Engler Goulart 30 October 2018 (has links)
Nódulos tireoidianos são um problema clínico comum, com prevalência de 1 a 76% a depender do método de avaliação e da população estudada. Cerca de 7 a 15% deles são malignos, podendo corresponder ao Carcinoma Papilífero (CPT), Carcinoma Folicular (CFT), Carcinoma Medular (CMT) ou Carcinoma Anaplásico. Estudos epidemiológicos recentes mostram um aumento de incidência do câncer de tireoide (CT), sobretudo devido ao CPT. Na avaliação etiológica do nódulo tireoidiano, são utilizados principalmente a ultrassonografia e a análise citológica por punção aspirativa com agulha fina (PAAF). Os resultados citológicos em nosso meio são reportados de acordo com o Sistema Bethesda, onde cada categoria (I a VI) tem seu risco de malignidade estimado e a conduta clínica recomendada. O objetivo deste estudo foi avaliar a efetividade da citologia de nódulos tireoidianos em um grupo populacional na região nordeste do estado de São Paulo, correspondente ao DRS VIII: quantificar os resultados pertencentes a cada categoria Bethesda e correlacionar com achados de tireoidectomia; calcular a prevalência do CT na amostra estudada; calcular o tempo entre a citologia e a cirurgia e verificar diferenças entre os tipos de assistência à saúde. Foram coletados dados de identificação, resultados de citologia dos nódulos e anatomopatológico das tireoidectomias do ano de 2014 nos três laboratórios de patologia do município de Franca, responsáveis por uma ampla cobertura local e regional, o que resultou numa amostra de 597 pacientes, 803 nódulos avaliados e 127 cirurgias. Dos 597 pacientes, 229 (38,3%) realizaram a PAAF utilizando o SUS, 312 (52,3%) a Saúde Suplementar (SS) e 56 (9,4%) foram exames particulares; 215 nódulos (26,7%) tiveram tamanho desconhecido e dos 588 nódulos com tamanho conhecido, o tamanho médio foi 1,8 cm (1,8 ± 1,2). Os resultados da citologia foram: Bethesda I 135 (16,8%); Bethesda II 475 (59,2%); Bethesda III 107 (13,3%); Bethesda IV 32 (4%); Bethesda V 20 (2,5%); Bethesda VI 34 (4,2%). Dos nódulos avaliados, 65,9% tiveram citologia B II, B V e B VI e 34,1% tiveram citologias B I, B III e B IV. Foram realizadas 127 tireoidectomias em 125 pacientes. De 210 nódulos operados, foi possível fazer a correlação entre a citologia e o laudo antomopatológico em 162 deles. Foram identificadas diferenças entre os sistemas público e privado na avaliação e tratamento da doença nodular tireoidiana na amostra. O tempo entre a citologia e cirurgia, o tamanho dos nódulos avaliados pela PAAF e dos nódulos operados foi maior em pacientes tratados pelo SUS. O principal motivo desta diferença seria a dificuldade de acesso a consultas especializadas, exames diagnósticos e cirurgias no SUS. A prevalência de CT na amostra foi 9,2% (55/597: 51 CPT, 3 CFT minimamente invasivos e 1 CMT), semelhante à descrita na literatura. 16/55 (29%) dos pacientes com CT, tiveram CPT menores que 1 cm. A citologia teve sensibilidade de 95%, especificidade de 50% e acurácia de 67,8% na detecção do CT. Este estudo confirmou que a citologia é um bom teste de triagem para CT em suas categorias B II, B V e B VI. Porém, existe grande limitação de desempenho da citologia nas categorias B I, B III e B IV, o que reforça a necessidade de combinação de testes diagnósticos como a US e os testes moleculares. / Thyroid nodules are a common clinical problem, with prevalence of 1 to 76% depending on the method of evaluation and the population studied. About 7 to 15% of them are malignant, and may correspond to Papillary Thyroid Carcinoma (PTC), Follicular Thyroid Carcinoma (FTC), Medullary Thyroid Carcinoma (MTC) or Anaplastic Carcinoma. Recent epidemiological studies have shown an increasing incidence of thyroid cancer (TC), mainly due to PTC. Ultrasound scanning and cytological analysis by fine needle aspiration (FNA) are used for the etiologic evaluation of thyroid nodules. In Brazil, cytological results are reported according to the Bethesda System, which estimates the risk of malignancy of each category (I to VI) and recommends the clinical management. The objectives of this study were to evaluate the effectiveness of FNA of thyroid nodules in a population group from the northeastern region of the state of São Paulo corresponding to DRS VIII; to quantify the results for each Bethesda category and to correlate them with thyroidectomy findings; to calculate the prevalence of TC in the sample studied, to calculate the time between cytology and surgery and to determine differences between the types of health care. Identification data, nodule cytology and anatomopathological diagnosis of thyroidectomies performed in 2014 were collected from three pathology laboratories in the city of Franca, responsible for a wide local and regional coverage, which resulted in a sample of 597 patients, 803 nodules evaluated and 127 surgeries. Taking all the 597 patients into consideration, 229 (38.3%) were submitted to FNA using the Unified Health System (SUS), 312 (52.3%) using the supplementary health (SS) and 56 (9.4%) were private examinations; 215 nodules (26.7%) were of unknown size and the mean size of 588 nodules of known size was 1.8 cm (1.8 ± 1.2). The results of FNA were Bethesda I 135 (16.8%); Bethesda II 475 (59.2%); Bethesda III 107 (13.3%); Bethesda IV 32 (4%); Bethesda V 20 (2.5%); Bethesda VI 34 (4.2%). Of the nodules evaluated, 65.9% had cytology B II, B V and B VI and 34.1% had cytologies B I, B III and B IV. A total of 127 thyroidectomies were performed in 125 patients. For 162 of the 210 operated nodules it was possible to correlate the cytology and anatomopathological results. Differences between the public and private systems were identified in the evaluation and treatment of thyroid nodular disease in the sample. The time between cytology and surgery, the size of the nodules assessed by FNA and the operated nodules were higher for the SUS cases. The main reason for this difference could be the difficulty in accessing specialized consultations, diagnostic exams and surgeries in SUS. The prevalence of TC in the sample was 9.2% (55/597: 51 PTC, 3 minimally invasive FTC and 1 MTC), similar to that described in the literature. 16/55 (29%) of TC patients had PTC less than 1 cm. Cytology showed 95% sensitivity, 50% specificity and 67.8% accuracy for the detection of TC. This study confirmed that cytology is a good screening test for CT in its B II, B V and B VI categories. However, the performance of cytology is greatly limited in categories B I, B III and B IV, supporting the need for a combination of diagnostic tests such as US and molecular tests.
263

An evaluation of selected interventions to raise participation at university within the UK widening participation policy context

Toloue Kashefpakdel, Elnaz January 2016 (has links)
The higher education system has undergone considerable change in the past fifty years. Increasing the number of students enrolled in university has been a focus of these changes. Despite the governments’ attempts in reducing the social class gap, there exist very large differences in those applying for r higher education. It seems despite the large socio-economic gap and the elitist image of attending university, UK government policies have not provided suitable support to reduce this gap. The level of concern over this subject has varied across different governments which could possibly have effects on young people’s transition from school across the different social classes. This thesis will address the difference between the New Labour and the Coalition governments’ level of attention to the issue of working class under-representation in universities and the policies they have developed to tackle it. It then investigates the effects of selected schemes designed to widen participation and explains how and why they are assumed to contribute to the reduction of the class gap in higher education participation. This study uses the dataset Longitudinal Study of Young People in England (LSYPE) to explore the relationship between attending widening access schemes and the likelihood of attending university during the New Labour office term. In doing so, and due to the shortage of direct measurements of state-funded widening participation programs, the analysis in this research uses school engagement activities as proxies. Additionally to provide an intergenerational comparison, given the differences in both data and policy environment, this research analyses the British Cohort Study 1970 data in order to provide further insights regarding the effectiveness of the then school engagement activities on university attendance. In other words, can the activities used to widen participation then provide greater insight into the kinds of programmes that might be effective in raising working class university participation? In turn this analysis provides the basis for an in-depth policy discussion of the issue.
264

Efeitos da adição de polietilenoglicol ao surfactante exógeno no tratamento da síndrome de aspiração de mecônio em coelhos recém-nascidos / Effects of polyethylene glycol added to exogenous surfactant for meconium aspiration syndrome treatment in newborn rabbits

João Cesar Lyra 06 March 2007 (has links)
O mecônio é um potente inativador da função do surfactante pulmonar, porém a reposição de surfactante exógeno para tratamento da síndrome de aspiração de mecônio em recém-nascidos tem efeito limitado e não diminui a mortalidade. Estudos mostram que a adição de polímeros como o polietilenoglicol (PEG) ao surfactante melhora sua atividade \"in vitro\" mantendo baixa tensão superficial. No presente estudo, avaliamos os efeitos da adição de PEG ao surfactante exógeno sobre a mecânica pulmonar e sobre a regularidade da expansão do parênquima pulmonar em coelhos recém-nascidos. Coelhos da raça New-Zealand-White, nascidos de parto cesáreo aos 30 dias de gestação, foram submetidos a traqueostomia e randomizados em 3 grupos de estudo de acordo com o tipo de tratamento administrado no décimo minuto de ventilação: grupo com aspiração de mecônio, sem tratamento com surfactante exógeno (MEC); grupo com aspiração de mecônio e tratamento com surfactante -100 mg/kg (S100); e grupo com aspiração de mecônio e tratamento com surfactante - 100 mg/kg adicionado de PEG -5% / 15 kDa (PEG). Mecônio humano foi administrado via traqueostomia na dose de 6 ml/kg e concentração de 65 mg/ml. Os animais dos três grupos foram submetidos à ventilação mecânica com pressão positiva no final da expiração de 3 cmH2O; freqüência respiratória de 60 incursões por minuto, fração inspiratória de O2 de 1,0 e pico de pressão inspiratória necessário para se manter volume-corrente fixo de 8 ml/kg. Os valores de complacência dinâmica, pressão ventilatória e volume-corrente foram obtidos a cada 5 minutos até o sacrifício com 20 minutos, com auxílio de um transdutor de pressão associado a um pneumotacógrafo, sendo analisados por um \"software\" específico. O surfactante foi produzido pelo Instituto Butantan (São Paulo, Brasil). Após a ventilação, foi realizada a curva pressão-volume e os pulmões foram fixados com formalina a 10%. A análise histológica foi feita calculando o diâmetro alveolar médio (Lm) e o índice de distorção através do desvio padrão do Lm. Análise estatística foi feita pela ANOVA One Way, com nível de significância de 0,05. Após 20 minutos de ventilação, os valores de complacência dinâmica (ml/cm H2O.kg) foram: 0,44±0,05 (MEC*); 0,68±0,12 (S100) e 0,59± 0,05 (PEG) e de pressão ventilatória (cm H2O): 18,40±2,02 (MEC*); 11,84±1,82 (S100) e 13,60±1,39 (PEG). Ambos os grupos tratados apresentaram padrão de expansão do parênquima mais homogêneo em relação aos animais não tratados: índice de distorção de 18,53±4,71 (MEC*); 8,41±2,35 (S100) e 11,73±4,28 (PEG) (*p < 0,05 vs outros grupos). Concluímos que os animais tratados com surfactante mostraram melhora significativa da mecânica pulmonar, com melhora da complacência pulmonar, menores valores de pressão ventilatória necessários para se manter o volume-corrente pré-estabelecido, maior volume pulmonar máximo e maior homogeneidade do padrão de expansão pulmonar, comparados ao grupo sem tratamento. Não houve influência da adição de polietilenoglicol ao surfactante com relação aos parâmetros avaliados. / Meconium is known to be a potent inactivator of pulmonary surfactant, and exogenous surfactant treatment for meconium aspiration syndrome failed to decrease mortality. A number of studies have shown, in vitro, that the addition of polymers such as polyethylene glycol (PEG) to the surfactant maintains good surface activity in the presence of meconium. In the present study we evaluated the effects of the (PEG) addition to the exogenous surfactant in the pulmonary mechanics and in the regularity of pulmonary parenchyma inflation in newborn rabbits. New-Zealeand-White rabbits born by c-section were submitted to tracheotomy and soon after human meconium (6 ml/kg - 65 mg/ml) was administrated through tracheotomy. A randomization was done after 10 minutes ventilation, into 3 study groups according to the surfactant treatment used: MEC (no treatment), S100 (100 mg/kg) and PEG (100 mg/kg added with PEG 5% / 15kDa). The animals were ventilated with 100 % oxygen, respiratory rate of 60 / minute and positive end-expiratory pressure of 3 cm H2O. Peak inspiratory pressure was adjusted to keep a steady tidal volume of 8 ml/kg. A ventilator-plethysmograph system was used and values of dynamic compliance, ventilatory pressure and tidal volume were recorded every 5 minutes, using specific software, within a period of 20 minutes. The surfactant was produced by Butantan Institute (Sao Paulo, Brazil). After the ventilation period, a PV-curve was performed and the lungs were fixed in 10% formalin. Histological analysis was assessed calculating the mean linear intercept (Lm) and lung tissue distortion (SDI) by the standard deviation of the Lm. Statistical analysis was made by ANOVA One Way, significance was set at 0.05. After 20 minutes of ventilation, dynamic compliance (ml/kg.cmH2O) was 0.44±0.05 (MEC*); 0.68±0.12 (S100) and 0.59±0.05 (PEG) and ventilatory pressure (cmH2O) was 18.40±2.02 (MEC*); 11.84±1.82 (S100) and 13.60±1.39 (PEG). Both groups receiving surfactant had lower mean linear intercept and more homogeneity in the lung parenchyma when compared with MEC group: SDI = 18.53±4.71 (MEC*), 8.41±2.35 (S100) and 11.73±4.28 (PEG) (*p < 0,05 vs all the other groups). We concluded that animals treated with surfactant showed significant improvement in pulmonary mechanics and more regularity of the lung parenchyma compared with non-treated animals. This improvement was found in both studied groups (independently of the PEG addition) without differences between them.
265

Effect of Maternal Age on Transcriptome of Granulosa Cells from Bovine Dominant Follicles

2014 January 1900 (has links)
Advanced maternal age has been shown to influence follicular and luteal dynamics in bovine ovary resulting in reduced fertility. The overall objective of the four studies presented in this thesis is to identify the maternal age-associated transcriptional changes in granulosa cells of the dominant follicles during follicle development. In the first study, mRNA expression levels of housekeeping genes were measured by real–time quantitative PCR (RT-qPCR) in granulosa cells of dominant follicles and FSH-stimulated follicles to select and validate suitable reference genes for relative gene expression analyses during maternal and follicular aging. Stability of six reference genes (GAPDH, ACTB, EIF2B2, UBE2D2, SF3A1 and RNF20) was analyzed using GeNorm, DeltaCT and NormFinder programs and comprehensive ranking order was determined based on these programs. Geometric mean of multiple genes (UBE2D2, EIF2B2, GAPDH and SF3A1) was more appropriate reference control than individual genes for the comparison of relative gene expression among dominant and FSH-stimulated follicles during maternal and/or follicular aging studies. In the second study, maternal age-associated changes in the transcriptome of granulosa cells recovered at the time of selection of the dominant follicle from aged (n=3) and young cows (n=3) were determined by EmbryoGENE bovine oligo-microarrays (EMBV3, Agilent Technology). The mRNA expression of five transcripts (CYP19A1, PCNA, GJA1, TPM2, and VNN1) was confirmed in a different set of granulosa cell samples by RT-qPCR to validate microarray data. A total of 169 genes/isoforms were differentially expressed (≥ 2-fold-change; P ≤ 0.05) in aged cows vs. young cows. These transcripts revealed inefficient 1) control of gonadotropins, and gonadotropin-induced changes in the cytoskeleton and extracellular matrix, 2) lipid metabolism and steroidogenesis 3) cell proliferation, cell cycle control and intercellular communication, and 4) higher oxidative stress responses in aged cows vs. young cows. In the third study, changes in the transcriptome of granulosa cells of the preovulatory follicle 24 h after LH treatment from aged (n= 3) and young (n=3) were determined. A total of 1340 genes were expressed differentially (≥ 2-fold change; P ≤ 0.05) in aged cows vs. young cows. The mRNA expression of five transcripts (RGS2, PTGS2, TNFAIP6, VNN1, NR5A2 and GADD45B) was confirmed in a different set of granulosa cell samples to validate microarray data. These transcripts were related to delayed 1) response to LH treatment 2) cellular differentiation and luteinization and 3) progesterone synthesis. Intra-follicle levels of progesterone were lower (P < 0.05) in aged cows compared to young and mid-aged cows. The fourth study compared the aged-associated changes in the transcriptome of granulosa cells during follicle development from the time of dominant follicle selection to preovulatory stage (24 h after LH). In comparison to young cows, aged cows expressed fewer differentially expressed genes/isoforms (1206 vs. 2260, respectively) at ≥ 2-fold-change (P ≤ 0.05) in the granulosa cells of the preovulatory (24 h after LH treatment) vs. the dominant follicle at selection. These transcripts in aged cows were related to late and inefficient 1) organization of cytoskeleton and cytoplasm, 2) differentiation, 3) lipid and cholesterol metabolism, 4) proliferation and 5) higher response to oxidative stress and free radical scavenging in the preovulatory follicles vs. the dominant follicle at selection. In conclusion, maternal age-alters the gene expression of granulosa cells of the dominant follicles during follicle development and results in a compromised follicular environment.
266

Etude numérique et expérimentale d'un compresseur aspiré

Godard, Antoine 24 November 2010 (has links) (PDF)
Afin d'alléger les moteurs d'avions et diminuer la consommation de carburant, les industriels tendent à rendre plus compact le système de compression de leurs moteurs, qui représente environ 40% de la masse totale. Or, à taux de compression global égal, la réduction du nombre d'étages implique une charge aérodynamique plus élevée par étage. Cela augmente d'autant les risques de décollements sur les aubes et la dégradation des performances. L'aspiration de la couche limite sur les aubages s'est révélée très prometteuse pour supprimer ces décollements néfastes et satisfaire aux besoins de charge aérodynamique élevée. Cependant, l'aspiration modifie fortement la distribution de pression statique à la paroi des aubes, rendant les approches de conception traditionnelles inadaptées. L'objectif de ce travail de thèse est donc de proposer une nouvelle méthode et de nouveaux critères de conception d'aubages fortement chargés, intégrant l'aspiration de la couche limite. Cette méthode repose sur une stratégie d'aspiration en deux étapes. Dans un premier temps, un contrôle passif, par courbure et diffusion, de la position du point de décollement est effectué dans le but de la rendre insensible aux conditions de fonctionnement. Dans un second temps, un contrôle actif par aspiration vise à placer la fente d'aspiration par rapport au point de décollement de manière à minimiser le taux d'aspiration nécessaire au recollement de la couche limite. Afin de mettre en pratique cette stratégie, une technique de dessin d'aubages par prescription de la distribution de courbure de l'extrados et de la variation de section du canal inter-aubes, est ainsi développée. Associée à un outil de pré-dimensionnement rapide ainsi qu'une évaluation des pertes de pression totale incluant la présence d'aspiration, cette méthode permet ainsi de concevoir une grille de stator aspirée subsonique réalisant une déflexion fluide de 60 degrés, pour un nombre de Mach amont de 0,5, correspondant à un facteur de diffusion de 0,73. Cette performance au point nominal est obtenue avec un coefficient de pertes de pression totale de 2,5%, en aspirant 1,1% du débit entrant dans la grille. Ces valeurs peuvent néanmoins être réduites respectivement à 2,1% et 0,8% par l'emploi d'une fente d'aspiration à bords arrondis. Cette étude numérique bidimensionnelle est effectuée à l'aide du code de calcul elsA de l'ONERA. Afin de valider expérimentalement cette méthode de conception ainsi que les outils numériques associés, une grille d'aubes plane est construite et testée à basse vitesse au laboratoire de Mécanique de Fluides et d'Acoustique de l'Ecole Centrale de Lyon. A mi-envergure, les résultats issus de l'expérience et de simulations numériques 3D confirment la pertinence de la stratégie d'aspiration et la démarche de conception adoptée. Cette confrontation met alors en évidence l'impact de la distribution du taux d'aspiration suivant l'envergure sur l'efficacité de l'aspiration. Etant donné l'importance des écoulements tridimensionnels rencontrés, une généralisation en trois dimensions de la stratégie d'aspiration est proposée et est appliquée numériquement sur cette même grille d'aubes. En contrôlant simultanément les couches limites se développant sur l'aube et sur les parois latérales du canal de compression, il est alors possible de supprimer presque totalement les décollements de coins présents dans celui-ci. En contrepartie, le taux d'aspiration voit sa valeur augmenter très fortement, tempérant ce bénéfice. L'épaisseur des couches limites entrantes se révèle alors également être un facteur déterminant pour le succès du contrôle des couches limites par aspiration, dans un cadre tridimensionnel.
267

Gebruik van regressie-analise in die identifisering van sportprestasiefaktore / The use of regression analysis in the identification of sport achievement factors

De Villiers, Liesel 11 1900 (has links)
Summaries in Afrikaans and English / Die doel van hierdie ondersoek was om te bepaal watler faktore die grootste bydrae tot sportprestasie lewer. Met die literatuurstudie is die verskillende faktore wat sportprestasie beinvloed, geidentifiseer en verder ondersoek en beskryf. Daar is gevind dat 'n wye verskeidenheid faktore bestaan wat atletelsportdeelnemers se prestasie positief of negatief kan beinvloed. 'n Empiriese ondersoek is uitgevoer waarby 'n aantal atlete/sportdeelnemers, wat aan verskeie sportsoorte deelneem, betrek is. Die afrigters van hierdie atlete/sportdeelnemers is oak by die ondersoek betrek. Eerstens is bepaal watter faktore, volgens die atlete/sportdeelnemers, die grootste bydrae tot hul sportprestasie lewer. Daama is hierdie geidenlifiseerde faktore aan 'n regressieanalise onderwerp om te bepaal walter faktor/e die grootste en belangrikste bydrae tot sportprestasie lewer. Die resultate het getoon dat hierdie faktore soos volg is: motivering, afrigter, kommunikasie, selfvertroue, aanleg en dieet / The purpose of this study was to determine which factors contribute significantly to sports achievement. In the literature study, different factors with an underlying effect on sports achievement were identified, explained and further investigated. A wide variety of factors bearing positive as well as negative effect on athletes'/sport participants' achievement were found. An empirical study was carried out in which a number of athletes/sport participators were involved. The coaches of these athletes/sport participants were also included. The factors that play a major contributing role in these athletes/sport participants' sports achievement were primarily determined. Thereafter the identified factors were further investigated through the use of a regression analysis to ascertain which ones contribute the most to sports achievement. The results indicated that these factors are as follows: motivation, coach, communication, self-confidence, talent and diet. / Educational Studies / M.Ed. (met spesialisering in Voorligting)
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Die invloed van prestasiewaardes op organisasieverbintenis van werknemers in die motornywerheid

Diedericks, Phillippus Cornelius 11 1900 (has links)
Summaries in English and Afrikaans / Text in Afrikaans / Die doel van hierdie verkennende studie was om ondersoek in te stel na die prestasiewaardes onderliggend aan Affektiewe, Kontinulteits- en Normatiewe organisasieverbintenis van werknemers binne die motorywerheid in Suid-Afrika. 'n Steekproef van 113 werknemers is uit verskillende motorhandelaars geselekteer. Daarna is ondersoek ingestel na watter prestasiewaardes betekenisvolle voorspellers van organisasieverbintenis is. Daar is bevind dat die prestasiewaardes mededinging en materiele welvaart betekenisvolle voorspellers van affektiewe organisasieverbintenis is, en dat die prestasiewaardes materiele welvaart en strewe na uitmuntendheid betekenisvolle voorspellers van kontinuiteitsorganisasieverbintenis is, maar dat geeneen van die prestasiewaardes wat huidig wereldwyd erken word, betekenisvolle voorspellers van normatiewe organisasieverbintenis in die motomywerheid is nie. Dit het verreikende irnplikasies vir die Suid-Afrikaanse motorhandelaar. Hierbenewens is dit ook duidelik uit die navorsingsresultate dat die prestasiewaardes mededinging, materiele welvaart en strewe na uitmuntendheid hulself daartoe leen om op 'n geintegreerde wyse deur bestuur van motorhandelaars aangewend te word ten einde hul kumulatiewe invloed op organisasieverbintenis optimaal te kan benut. / The objective of this exploratory study was to investigate the performance values subjacent to affective, continuity and normative organisation commitment of employees in the motor industry in South Africa. A sample of 113 employees was selected from different dealerships. Thereafter an investigation was done to establish which performance values were meaningful predictors of organisation commitment. It was found that the performance values competition and material gain were meaningful predictors of affective organisation commitment, and the performance values material gain and excellence were meaningful predictors of continuity organisation commitment, but that none of the performance values which are contemporarily recognised world-wide were meaningful predictors of normative organisation commitment. This has far-reaching implications for South African motor dealers. It was also apparent from the results that the performance values competition, material gain and excellence can be utilized in an integrated way by management of motor dealers in order to ensure optimal utilization of their cumulative impact on organisation commitment. / Industrial psychology / M.Com. (Industrial Psychology)
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Detekce minimální reziduální choroby v kostní dřeni a periferní krvi u pacientek s karcinomem prsu. / Detection of minimal residual disease in bone marrow an peripheral blood in patients with breast cancer.

Čabiňaková, Michaela January 2015 (has links)
Introduction: Simultaneous detection of disseminated tumor cells (DTCs) and circulating tumor cells (CTCs) was shown to be associated with an especially poor prognosis and increased incidence of disease-related deaths in non-metastatic breast cancer patients. We analyzed the occurance of DTCs in bone marrow and CTCs in peripheral blood in patients with primary breast cancer, we evaluated the correlation of their presence with other prognostic markers and we investigated the changes in DTCs/CTCs number at different time points during treatment. Materials and methods: Blood of 50 patients with primary breast cancer were used for immunomagnetic separation and detection of circulating tumor cells using the commercial available system the AdnaTest Breast Cancer™ (AdnaGen GmbH, Langenhagen, Germany). Bone marrow aspirates from 50 patients were analyzed for DTCs by immunocytochemistry using the pancytokeratin antibody conjugated with FITC (Monoclonal Anti-Cytokeratin antibody F3418, Sigma Aldrich, USA). Results: DTCs were identified in 30% (15/50) and CTCs in 22% (11/50) of patients. We found that DTC positivity could point to a significantly high risk of larger primary tumor size (p- value 0.011) and significantly higher risk of lymph node involvement (p- value 0.002). For CTC positivity, no such...
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Desempenho da ultrassonografia e da punção aspirativa por agulha fina axilar em pacientes com carcinomas invasivos da mama: correlação com aspectos do linfonodo e características tumorais / Performance of ultrasound and axillary FNA in patients with invasive breast carcinomas: correlation with lymph node and tumor characteristics

Patricia Akissue de Camargo Teixeira 08 August 2017 (has links)
INTRODUÇÃO: O status linfonodal da axila ainda permanece como importante fator prognóstico em pacientes com câncer de mama invasivo. Muitos estudos já relataram a importância da ultrassonografia axilar e da punção aspirativa por agulha fina (PAAF) na avaliação pré-operatória das pacientes com câncer de mama. Nossos objetivos foram avaliar as características ultrassonográficas dos linfonodos axilares relacionadas à metástase linfonodal e o papel da PAAF na avaliação pré-operatória de pacientes com câncer de mama. Nosso objetivo secundário foi avaliar se, dependendo das características dos tumores, linfonodos sem alterações na ultrassonografia poderiam ter comprometimento metastático. MÉTODOS: Este estudo foi realizado no Instituto de Radiologia e no Instituto do Câncer do HCFMUSP. Foram incluídas 182 pacientes com câncer de mama invasivo recém-diagnosticado, sendo que, destas, apenas 145 realizaram cirurgia - 74 prosseguiram direto para cirurgia e 71 realizaram tratamento neoadjuvante e após cirurgia. Foi realizada avaliação ultrassonográfica da axila ipsilateral ao tumor e punção aspirativa por agulha fina de um linfonodo selecionado pelo radiologista. Os dados ultrassonográficos dos linfonodos e os achados citológicos da PAAF foram correlacionados com os resultados anatomopatológicos da biópsia do linfonodo sentinela ou do esvaziamento axilar. RESULTADOS: Nas 74 pacientes (75 axilas) que não realizaram tratamento neoadjuvante, as características ultrassonográficas do linfonodo associadas à metástase na análise univariada foram espessamento cortical difuso e a obliteração parcial ou completa do hilo gorduroso. A sensibilidade, especificidade, acurácia, valor preditivo positivo (VPP) e valor preditivo negativo (VPN) da ultrassonografia foram, respectivamente, 72,7%, 57,1%, 64,0%, 57,1% e 72,7% (p=0,009), e da PAAF: 36,4%, 97,6%, 70,7%, 92,3% e 66,1% (p < 0,001). Incluindo apenas linfonodos alterados na ultrassonografia, obtivemos, respectivamente, sensibilidade, especificidade, acurácia, VPP e VPN de 50%, 94%, 69%, 92% 59% (p=0,001). Nenhuma PAAF de linfonodo classificado como normal na ultrassonografia teve resultado positivo. Obtivemos, nas análises das curvas ROC, um valor de corte da espessura da cortical de 2,65 mm (p < 0,001) e do tamanho do tumor pré-cirúrgico de 2,45 cm (p=0,042). Na análise multivariada, as seguintes características foram associadas à metástase linfonodal: espessura da cortical (p = 0,005), tamanho do tumor pré-cirúrgico (p = 0,030), status pré-menopausa (p = 0,017), tipo histológico não especial (p = 0,034) e localização do tumor no quadrante superolateral (p = 0,011). Construiu-se um modelo de predição de risco de metástase axilar usando estas características. Nas 71 pacientes que realizaram tratamento adjuvante, a única característica do linfonodo associada à metástase linfonodal foi a forma redonda ou irregular. Os demais resultados deste grupo não podem ser generalizados, pois não é possível separar o efeito do tratamento nesta população. CONCLUSÕES: Linfonodos axilares com espessamento cortical difuso e com obliteração parcial ou completa do hilo gorduroso estão associados à malignidade. A PAAF apresentou-se mais útil nos linfonodos alterados, com sensibilidade de 50%. Pacientes com PAAF positivas devem ser encaminhadas para esvaziamento axilar ou quimioterapia neoadjuvante. Não há benefício da realização da PAAF em linfonodos sem alterações na ultrassonografia / BACKGROUND: The lymph node status of the axilla remains an important prognostic factor in patients with invasive breast cancer. Many studies have already reported the importance of axillary ultrasonography and fine needle aspiration (FNA) in the preoperative evaluation of patients with breast cancer. Our objectives were to evaluate the ultrasound characteristics of axillary lymph nodes related to lymph node metastasis and the role of FNA in the preoperative evaluation of patients with breast cancer. Our secondary objective was to assess whether, depending on the tumor characteristics, lymph nodes that showed no change on ultrasonography could have metastatic involvement. METHODS: This study was conducted at the Institute of Radiology and the Institute of Cancer of HCFMUSP. A total of 182 patients with newly diagnosed invasive breast cancer were included, of whom only 145 had undergone surgery - 74 went straight to surgery and 71 underwent neoadjuvant treatment and after surgery. Ultrasound evaluation of the axilla ipsilateral to the tumor and fine needle aspiration of a lymph node selected by the radiologist were performed. The ultrasound data of the lymph nodes and the cytological findings of FNA were correlated with pathology results from sentinel lymph node biopsy or surgical dissection. RESULTS: In the 74 patients (75 axillae) who did not undergo neoadjuvant treatment, the ultrasound characteristics of the lymph nodes associated with metastasis in the univariate analysis were diffuse cortical thickening and partial or complete fatty hilum obliteration. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of ultrasound were respectively 72.7%, 57.1%, 64.0%, 57.1% and 72.7% (p = 0.009) and of the FNA 36.4%, 97.6%, 70.7%, 92.3% and 66.1% (p <0.001). Including only atypical lymph nodes on ultrasonography, we obtained respectively sensitivity, specificity, accuracy, PPV and NPV of 50%, 94%, 69% 92% and 59% (p = 0.001). No FNA of lymph node classified as normal on ultrasonography had a positive result. With ROC curves analysis we obtained a cut-off value of cortical thickness of 2.65 mm (p <0.001) and pre-surgical tumor size of 2.45 cm (p = 0.042). In the multivariate analysis, the following characteristics were associated with lymph node metastasis: cortical thickness (p = 0.005), preoperative tumor size (p = 0.030), premenopausal status (p = 0.017), non-special histological type and tumor location in the upper outer quadrant (p = 0.011). A predictive model of axillary metastasis risk was constructed using these characteristics. In the 71 patients who underwent adjuvant treatment the only feature of the lymph node associated with lymph node metastasis was the round or irregular shape. The other results of this group cannot be generalized since it is not possible to separate the treatment effect in this population. CONCLUSIONS: Axillary lymph nodes with diffuse cortical thickening and with partial or complete fatty hilum obliteration are associated with malignancy. FNA was more useful in atypical lymph nodes, with a sensitivity of 50%. Patients with positive FNA should be referred for axillary surgical dissection or neoadjuvant chemotherapy. There is no benefit of performing FNA in lymph nodes without changes in ultrasound

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