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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.
181

Influência do treinamento muscular inspiratório sobre a função respiratória e qualidade de vida de pacientes com doença renal crônica em hemodiálisee a relação com a composição corporal e com a capacidade aeróbia

Soares, Viviane 30 June 2014 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-01-27T14:59:14Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese - Viviane Soares - 2014.pdf: 1975633 bytes, checksum: e3190782e47ad3342d7bdc080356bd0f (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-01-28T13:30:31Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese - Viviane Soares - 2014.pdf: 1975633 bytes, checksum: e3190782e47ad3342d7bdc080356bd0f (MD5) / Made available in DSpace on 2015-01-28T13:30:31Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese - Viviane Soares - 2014.pdf: 1975633 bytes, checksum: e3190782e47ad3342d7bdc080356bd0f (MD5) Previous issue date: 2014-06-30 / Chronic kidney disease (CKD) and its treatment, hemodialysis, favors the increase of comorbidities to patients and the protein-energy malnutrition is the main complication, with consequent wasting of muscle tissue that reduce muscle strength, lung function and oxygenation of body tissues resulting in poor functional capacity, cardiorespiratory fitness and quality of life of these patients. Therefore, the objective of this study was to compare body composition between hemodialysis patients and healthy subjects, to evaluate cardiorespiratory fitness by oxygen uptake ( peak VO2  ) and the effects of inspiratory muscle training (IMT) on respiratory function and quality of life of male patients on hemodialysis. A clinical trial was conducted with 62 patients, aged 22-71 years. Body composition was estimated by vectorial bioelectrical impedance and anthropometric measures. Respiratory muscle strength was assessed by manometer to obtain the maximal inspiratory (Pimax) and expiratory pressures (Pemax). Pulmonary function and classification of respiratory disorders were examined by spirometry. Cardiorespiratory fitness was assessed by cardiopulmonary exercise test performed on a treadmill using the Bruce protocol which was adapted to estimate peak oxygen uptake ( peak OV 2  ). The aspects of quality of life were assessed by questionnaire KDQOL - SF (Kidney Disease Quality of Life - Short Form). The IMT was held for six months during the sessions and always at the first two hours of hemodialysis. Two training devices were used: a specific trainer and a respiratory incentive associated with two breathing exercises. The respiratory function of patients was evaluated before, during and after the inspiratory muscle training. The results were presented in three studies. In the first study, the comparison of body composition between hemodialysis patients and healthy subjects indicated differences for triceps skin fold (p<0.001) and arm circumference (p<0.001), but not for arm muscle circumference and area. The vectorial bioelectrical impedance indicated patients in dehydration and reduced body cell mass when compared with healthy subjects. In the second study was analyzed the usefulness of respiratory parameters to detect patients with poor functional capacity ( peak OV 2  below 70 % of predicted). The Pimax (β=-0.037, p=0.014) and percentage of predicted forced vital capacity - FVC % (β=-0.056, p=0.025) were significant to identify patients with poor functional capacity predictors and the ROC curve established cutoff points for MIP (<74 cmH2O) and % FVC (<79%). In the third study were verified the effects of IMT on respiratory muscle strength, lung function and quality of life of hemodialysis patients. After training muscle strength was found significant increase in respiratory strength in both groups. The group that used incentive spirometry had greater increment to inspiratory strength (39.80%) than the group that used the specific trainer (28.30%). The aspects related to quality of life, found significant differences for the dimensions cognitive function (p=0.03), sexual function (p=0.009) and social function (p=0.04) in the group that trained with specific trainer, and to physical function (p=0.03) in the group that trained with incentive spirometry. The results of this study show that male patients in hemodialysis exhibit differences in body composition when compared with healthy subjects; inspiratory muscle strength and percent of vital capacity predicted for age can be used as predictors of poor functional capacity in this group of patients; and finally, inspiratory muscle training improved inspiratory muscle strength and aspects related to the quality of life of the two trained groups. / A doença renal crônica (DRC) e o seu tratamento, hemodiálise, estão associados com o surgimento de comorbidades, tais como, alterações hormonais, aumento da resposta inflamatória, as doenças cardiovasculares e a desnutrição energético-protéica, com consequente perda de tecido muscular. Essa perda reduz a força muscular respiratória e a função pulmonar e culmina na reduzida capacidade funcional, aptidão cardiorrespiratória e qualidade de vida destes pacientes. Considerando o exposto acima, o objetivo deste estudo foi avaliar a composição corporal, a capacidade aeróbia e os efeitos do treinamento muscular inspiratório (TMI) sobre a função respiratória e a qualidade de vida de pacientes do sexo masculino, submetidos à hemodiálise. Foi realizado um ensaio clínico com 62 pacientes, com idade entre 22-71 anos. A composição corporal foi estimada pelas medidas antropométricas e bioimpedância vetorial. A força muscular respiratória foi avaliada a partir da manovacuometria para obtenção das pressões inspiratória (Pimax) e expiratória máximas (Pemax). A função pulmonar e a classificação dos distúrbios ventilatórios foram examinadas pela espirometria. A aptidão cardiorrespiratória foi avaliada pelo teste de esforço cardiopulmonar, realizado em esteira e com a utilização do protocolo de Bruce que foi adaptado para estimar o consumo de oxigênio de pico ( pico OV 2  ). Os aspectos relacionados à qualidade de vida foram avaliados pelo questionário KDQOL-SF (Kidney Disease Quality of life – Short Form). O treinamento inspiratório foi realizado por seis meses durante as sessões e sempre nas primeiras duas horas da hemodiálise. Dois dispositivos de treinamento foram utilizados: um treinador específico e um incentivador respiratório associado a dois exercícios respiratórios. Os pacientes foram examinados quanto à função respiratória antes, durante e após o treinamento muscular inspiratório. Os resultados foram apresentados em três estudos. No primeiro estudo a comparação da composição corporal de pacientes em hemodiálise com a de sujeitos saudáveis indicaram diferenças para dobra cutânea tricipital (p<0,001) e circunferência de braço (p<0,001), mas, nenhuma para circunferência e área muscular de braço. A análise da bioimpedância vetorial indicou pacientes em estado de desidratação e redução de massa celular. No segundo estudo foi analisada a utilidade de parâmetros respiratórios para detectar pacientes com pobre capacidade funcional ( pico OV 2  abaixo de 70% do predito). A Pimax (β=-0,037; p=0,014) e a porcentagem predita da capacidade vital forçada - %CVF (β=-0,056; p=0,025) foram considerados preditores significativos para identificar os pacientes com pobre capacidade funcional e a curva ROC estabeleceu os pontos de corte para Pimax (<74 cmH2O) e %CVF (<79%). No terceiro estudo foram verificados os efeitos do TMI sobre função respiratória e a qualidade de vida dos pacientes em hemodiálise. Após o treinamento a força inspiratória aumentou, significativamente, nos dois grupos. O grupo que usou o incentivador respiratório teve maior incremento de força inspiratória (39,80%) que o grupo que utilizou o treinador específico (28,30%). Quanto à qualidade de vida, foram encontradas diferenças significativas para as dimensões função cognitivas (p=0,03), função sexual (p=0,009) e função social (p=0,04) no grupo que treinou com dispositivo específico; e para a dimensão função física (p=0,03) no grupo que treinou com incentivador respiratório. Conclui-se que os pacientes, do sexo masculino, em hemodiálise apresentam diferenças na composição corporal quando comparados com sujeitos saudáveis; a Pimax e a %CVF predita para idade podem ser utilizadas como preditores de pobre capacidade funcional nesse grupo de pacientes; e por último, o TMI melhorou de forma significativa a força inspiratória e os aspectos relacionados à qualidade de vida dos dois grupos treinados.
182

\"Avaliação da resistência flexural, microinfiltração e grau de conversão de uma resina composta fotoativada com luz halógena e laser de argônio\" / Evaluation of the flexural strenght, microleakage and degree of convertion of a composite resin photocured with argon laser and halogen lamp.

Patricia Ramos Lloret 13 February 2007 (has links)
Nesta pesquisa foi avaliado a resistência flexural, a microinfiltração e o grau de conversão de uma resina composta micro-híbrida fotoativada por laser de argônio e luz halógena. Para o teste de resistência flexural e grau de conversão foram preparadas cinco amostras de 25 X 2 X 2mm de acordo com a norma ISO 4049. Os parâmetros de fotoativação utilizados em todas as etapas do trabalho foram: luz halógena (500mW/cm2) por 20 segudos, laser de argônio (250mW) por 10 e 20 segundos. As amostras foram lixadas com a seqüência de granulações 500, 800, 1000, 1200, 2500 e 4000. Os espécimes eram armazenados em água destilada, em recipiente escuro, em estufa a 37ºC por 24 horas e eram submetidos ao ensaio de resistência flexural (Máquina de Ensaios Mecânicos - Modelo 4411 ? Instron) em velocidade de 1mm/min. Para o estudo da microinfiltração foram utilizados dentes incisivos bovinos (n=20), As cavidades eram preparadas com brocas Carbide #330 com 4mm (altura) X 3mm (largura) X 2mm (profundidade). Os dentes eram então restaurados, e recebiam acabamento e polimento e em seguida eram armazenados em água destilada, em estufa a 37ºC por 24 horas. As amostras foram submetidas ao processo de termociclagem (500 ciclos de 30 segundos - 6ºC e 60ºC). Após a termociclagem, os ápices dos dentes eram selados com IRM e adesivo a base de cianoacrilato e imersos em fucsina básica a 0,5% por 24 horas, em estufa a 37ºC. A análise do grau de conversão foi feita com o Espectrômetro FT-Raman RFS 100/S (Bruker). Para o teste de resistência flexural foi realizado o teste de análise de variância, que mostrou não haver diferença estatisticamente significante entre as fontes fotoativadoras estudadas (p>0,05). A microinfiltração das margens oclusais (em esmalte) e gengivais (em dentina) dos três grupos foram analisadas separadamente por meio do teste de Mann-Whitney. Houve diferença estatisticamente significante ao nível de 5% entre esmalte e dentina, sendo que em todos os grupos a microinfiltração em dentina foi maior que em esmalte. O teste nãoparamétrico Kruskall-Wallis foi utilizado separadamente nas comparações entre as fontes para as análises do grau de microinfiltração em esmalte e dentina. Não houve diferença estatisticamente significante em ambas as comparações, sendo o valor de H= 0,1283 para esmalte e de H=2,3083 para em dentina. Para a análise do grau de conversão foi realizada a análise de variância (ANOVA) entre os grupos. Não houve diferença estatisticamente significante entre as fontes. Diante dos resultados obtidos, pode-se afirmar que o laser de argônio apresentou qualidade de fotoativação semelhante à da luz halógena e que nenhuma fonte ativadora estudada foi capaz de evitar a microinfiltração. / In the research was evaluated the flexural strength, the microleakage and the degree of conversion of a micro-hybrid composite resin photocured with argon laser and halogen lamp. For both flexural test and degree of conversion analysis five bar samples of composite resin (25 X 2 X 2mm) were prepared and polymerized following the ISO 4049. The light cured unit halogen was used with 500mW/cm2 for 20 seconds and the argon laser with 250mW for 10 and 20 seconds. After curing, samples were removed from the molds, polished using silicon carbide paper up to 4000 grit-number and stored in distilled water in dark environment at 37oC for 24 hours. The flexural property was quantified by a three-point loading test (Model 4411, Instron Corp., Canton, MA) with a cross-head speed of 1,0mm/min. To microleakage test sixty bovine incisors were used to prepare standardized class V cavities that were restored and polished. The specimens were stored in water for 24 hours at 37oC and thermocycled 500 times between water baths kept at 5 oC and 55 oC. After thermocycling, specimens were immersed in a aqueous solution of basic fuchsin for 24 hours. Longitudinal sections of each restoration were obtained and examined with a stereomicroscope for qualitive evaluation of microleakage. FTRaman RFS 100/S spectrometer (Bruker) was used to analyse the degree of conversion. The ANOVA test showed that there were no statistically significant difference of the flexural setrength between the photo-activation types evaluated in the flexural study. Microleakage data was statistically analysed by Mann-Whitney and Kruskall-Wallis tests. Enamel margins resulted in statistical lower degree of leakage than dentin margins. There was no statistically significant difference between the three types of photo-curing studied. The ANOVA test also showed that there were no statistically significant difference of the degree of conversion between the studied groups. According to the methodology used in this research it was concluded that the argon laser is a posible alternative for photocuring, providing the same quality of polymerization as do the halogen lamp. None of the photocured units tested in this study completely eliminated microleakage.
183

Procédé de recyclage de mélanges ABS-PC issus de déchets d’équipements électriques et électroniques (DEEE) / Mechanical recycling of PC-ABS blend from waste electrical and electronic equipement

Ausset, Sandrine 08 February 2013 (has links)
L’objectif de cette thèse est de proposer un procédé de recyclage de mélanges ABS-PC issus des Déchets d’Equipements Electriques et Electroniques (DEEE) réels capable de s’affranchir des contraintes liées au recyclage des polymères.Ces contraintes sont liées, entre autre, à la présence d’impuretés (autres polymères) après l'étape de tri et au procédé de remise en forme. L’influence de la présence d’impureté dans un alliage ABS-PC sur ces propriétés mécaniques (résistance au choc et traction) a donc été étudiée en s’appuyant sur des observations morphologiques. Il s’est avéré que la présence d’impureté non miscible conduit à la dégradation des propriétés mécaniques de l’ABS-PC. L’ajout de compatibilisants a été étudié afin de masquer l’effet de l’impureté. Il a ainsi été montré que l’amélioration de la résilience du mélange (ABS-PC/impureté) est intimement liée à la modification de la morphologie et à la nature de l’adhésion aux interfaces. Il a ensuite été constaté que l’optimisation des paramètres de mise en oeuvre engendre une modification de la morphologie. Cette modification peut entrainer une augmentation de la résistance au choc.Ces deux méthodes ont ensuite été appliquées à un mélange d’ABS-PC ignifugé issu des DEEE contenant une impureté. L’ajout de compatibilisant et de la modification des paramètres de mise en oeuvre améliore la résilience. En revanche, cela a un effet néfaste sur le comportement au feu de l’alliage ABS-PC ignifugé. / The aim of this PhD work was to propose a recycling process method of PC-ABS blend from real Waste Electrical and Electronic Equipment deposit (WEEE) deposits. This recycling process has to be able to overcome the problematic related to polymer recycling.The main constraints about recycling process are the presence of polymeric impurities after sorting step as well as mechanical reprocessing (extrusion and injection molded). Firstly, the effect of impurities on the mechanical properties (tensile and impact strength) and morphology (SEM, TEM) of PC-ABS blends have been studied. The presence of immiscible impurity deteriorates the mechanical properties of PC-ABS. The addition of an appropriate compatibilizer enhances the interface between PC-ABS and the impurity. The compatibilizer improves the impact strength and changes the morphology of this blend. Secondly, the optimization of injection molding parameters generates a change in morphology. This change leads to an increase of the impact strength.Both methods were applied to a flame retardant PC-ABS from WEEE with an impurity. The addition of a compatibilizer and the modification of injection molding parameters improve the impact strength. The presences of an impurity and a compatibilizer have a negative effect on the flame retardant properties of the PC-ABS blend
184

Experimental and numerical study of confined masonry walls under in-plane loads : case : guerrero State (Mexico) / Étude expérimentale et numérique des murs en maçonnerie confinée chargés dans leur plane : cas : état de Guerrero (Mexique)

Sánchez Tizapa, Sulpicio 10 December 2009 (has links)
Cette recherche propose des méthodes d’amélioration de résistance et d’évaluation du comportement de murs en maçonnerie confinée construits en briques solides d’argile cuite. Ces éléments sont largement utilisés dans la construction des bâtiments à l’État du Guerrero (Mexique) lesquels doivent résister charges séismiques importantes. Ainsi, un programme expérimental a été développé pour évaluer les propriétés mécaniques des briques et de la maçonnerie, qui sont nécessaires dans la conception et analyse des constructions. Pour augmenter la résistance de la maçonnerie et compenser la variabilité de la résistance à la compression des briques, un mortier à haute résistance et un renfort métallique dans les joints ont été utilisés. Certaines propriétés mécaniques sont égales à celles communément citées, cependant, les autres ont des valeurs deux fois plus grandes. Dans cette région du pays, les trois premiers tests de murs à échelle réelle construits en briques solides d’argile cuite ont été réalisés sous charge latérale alternée afin d'évaluer son comportement. Un renfort métallique et une couche du mortier ont été placés dans les surfaces de deux murs. Ceux-ci ont présenté un bon comportement et le renfort a eu un comportement structural adéquat. Avec les données expérimentales, plusieurs modèles numériques de panneaux et de murs ont été mis au point afin de reproduire l'enveloppe de résistance et le mode de défaillance. Ces modèles ont également évalué l'influence des propriétés mécaniques des briques et des joints sur le comportement global des spécimens. Aussi, un renfort métallique a été placé à l’intérieure des joints dans deux modèles. D'un autre côté, à partir de résultats expérimentaux obtenus et cités, une loi de comportement de la maçonnerie a été définie pour construire un modèle simple qui donne des résultats concordants à la fois avec les résultats expérimentaux et ceux obtenus par la méthode des éléments finis. Finalement, deux modèles simplifiés ont été proposés afin d’évaluer la résistance de murs en maçonnerie en supposant que le plan de rupture est suivant la diagonale du mur. L'un suppose la rupture de la maçonnerie par effet de cisaillement tandis que l'autre suppose la rupture par effet de tension induite. Le ratio entre résistance théorique et résistance expérimentale a été acceptable pour 27 murs faits de matériaux différents et testés sous différents types de chargement où le ratio hauteur sur longueur varie entre 0,7 et 1,26 / This research work proposes methods to rises the resistance and to evaluate the behavior of confined masonry walls built from clay solid bricks. These elements are widely used in Guerrero State (México) to build masonry structures, which should resist high lateral loads because of the serious seismic hazard. Therefore, a large experimental program to evaluate the mechanical properties of bricks and masonry currently required in the design process and masonry analysis was developed. To rises the masonry resistance and to counteract the influence of the compressive strength of the pieces on the masonry behavior, a high compressive strength mortar and a metallic reinforcement inside the joints were used. With respect to referenced values of the mechanical properties, some were similar and others were twice bigger. In this country zone, the first three tests under lateral load on full-scale confined masonry walls built from clay solid bricks were carried out in order to evaluate its behavior. A reinforcement composed by metallic hexagonal mesh-mortar coat was placed on the faces of two walls to rise or to restore the resistance. The walls showed good behavior and the reinforcement had adequate structural efficiency. Numerical models of panels and walls built by using the experimental data evaluated the envelope resistance, the failure mode and showed the influence of the mechanical properties of the pieces and joints on the global behavior. Two models had metallic reinforcement inside the joints. In addition, a constitutive law of the masonry defined from experimental results allowed to elaborate a simple model, which results were concordant with respect to the experimental results and similar to those calculated by complex models. Finally, two simplified models to evaluate the resistance of confined masonry walls by considering the failure plane on the wall diagonal were developed. One supposes the masonry failure by shear effect and the other supposes the masonry failure by induced tension. The ratio theoretical resistance vs. experimental resistance was adequate for walls built from different materials and tested under different loads, which had ratio Height/Length ranging from 0.74 to 1.26
185

Reaktivní práškové kompozity a cementové kompozity bez makropórů / Reactive powder composites and cement composites without macropores

Panenková, Monika January 2018 (has links)
This diploma thesis deals with the design principles and manifacture of ultra performance concrete (UHPC), reactive powder composites (RPC) and other fine-grained materials, such as Macro defect free (MDF) or Densified systems with small particles (DSP). Theoretical part of this work is focused on the requirements of properties and composition UHPC and RPC and methodology of their design principles. Experimental part describes design principles RPC, manufacture of test specimens, testing of certain physical and mechanical properties, such as tensile strenght, bending strenght and compressive strenght and determination chemical character X-ray and thermal analysis.
186

Možnosti laboratorní přípravy a testování stříkaných betonů / Possibilities of laboratory preparation and testing of shotcrete

Helan, Tomáš January 2013 (has links)
The master's thesis is focused on the posibility of laboratory testing of shotcrete. The important point of the thesis is properties comparison of shotcrete made in laboratory with vibrating press and concrete with the same recipe made by spraying machine. The influence of shotcrete recipe, type and dosage of accelerating ingredient is also examined.
187

Konstrukční návrh letounu Avia BH534 v ultralehkém provedení / Avia BH534 airplane design as ultralight

Kozelský, Martin January 2010 (has links)
The object of the diploma thesis is a preparation of fundamental bases for realization aerofoils of the replica of the biplane aircraft BH534 Avia. The preambule of the work balances replica against the real historic aircraft. As next the basic aerodynamics characteristics, construction of aerofoils and strenght calculation of the aerofoils are described.
188

Návrh separátoru / Design of separator

Bukal, Oldřich January 2013 (has links)
Diploma thesis is focused on design and strenght calculation of the separator according to ČSN EN 13 445. Introductory part introduce problems with design of separators, in the other parts there is a design and strenght calculation of separator according to ČSN EN 14 445, unfired pressure vessels, part 3 - Design, FEM analysis in ANSYS Workbench and stress categorization of the results.
189

Pohon vřeten pětivřetenového soustružnického automatu / Desingn of independent drives for five-spindle automatic lathe

Pavelka, Radomil January 2014 (has links)
The subject of the thesis is design of independent spindle drive for multi-spindle automatic lathe MORI-SAY TMZ 520 CNC manufactured by TAJMAC-ZPS. The thesis will introduce the representatives of manufacturing program of TAJMAC-ZPS multi-spindle automatic lathes division and there will be a brief description of their main constructional parts. The main objective of the thesis is an engineering design of testing device which will be bulit for verification of the correct drive concept. There is also many calculations and detailed description of the engineering design. The testing device is made for internal needs of TAJMAC-ZPS.
190

Studené asfaltové směsi s R-materiálem / Cold asphalt mixtures with R-material

Ševc, Jan January 2016 (has links)
The thesis is focused on the use of R-material into cold asphalt mixtures. It deals with cold recycling and with input materials for this technology. It verifies properties of R-material and residues of bituminous binder. It also verifies properties of designed cold asphalt mixtures by the probative controls (indirect tensile strenght and water resistance). Furthermore is focused on the experimental measurement of selected mixtures to ensure more characteristics. The amount of homogenity of R-material, quantity and quality of residues bituminous binder is essential for positive results.

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