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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.
41

Avaliação de oxigenadores de sangue utilizando principios de transferencia de massa e tecnica de perda de carga / Membrane blood oxygenator evaluation using mass transfer principles and head loss techniques

Schmutzler, Luis Melchert Faber 31 August 2004 (has links)
Orientadores: Antonio Celso Fonseca de Arruda e Waldyr Parolari Novello / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-04T02:53:24Z (GMT). No. of bitstreams: 1 Schmutzler_LuisMelchertFaber_D.pdf: 18427607 bytes, checksum: a256aa1b714dbaf8eeb63daf6be84dd1 (MD5) Previous issue date: 2004 / Resumo: Oxigenadores de sangue tipo de membrana são construídos para trocarem gases de respiração através de uma área de contato, a sua chamada área de troca. Devido a características do processo de fabricação, esta área pode softer variações. Neste trabalho procurou-se desenvolver métodos de avaliação da variação desta área, por meio da medição da transferência de massa e da perda de carga. A técnica utilizando transferência de massa gerou dois métodos de avaliação, um utilizando como fase líquida a água destilada e o outro, uma emulsão de perfluorcarbono. No intuito de assegurar a funcionalidade da emulsão disponível e assim a precisão do trabalho, foi desenvolvido um método de validação para se avaliar a capacidade de dissolver Oxigênio da mesma. O outro método para avaliação da área de troca é baseado naperda de carga, sofrida por um fluxo de gás ao percorrer o circuito de membranas do oxigenador sob teste. Todos os métodos apresentaram resultados suficientemente satisfatórios, permitindo estabelecer diferenças de desempenho entre as unidades testadas e a validação da área de troca, por comparação com um padrão sendo que, os métodos de transferência de massa com água e o da perda de carga com gás são métodos não destrutivos. Os resultados obtidos utilizando-se o método com gás forneceram uma melhor resolução / Abstract: Membrane blood oxygenators are built to exchange perspiration gases thru an exchange area, but due to the fabrication process characteristics, this exchange area may vary. In this work, exchange area evaluation methods were developed using mass transfer and head loss techniques. The mass transfer technique generated two methods, one using distilled water and other using perfluorocarbon emulsion. Envisaging assurance on the functionality of the perfluorocarbon emulsion and by the way, the quality of the work, a method for evaluating the Oxygen solving capability was also developed. The other area evaluation method is based on a gas flow head loss while passing thru the membrane inside of the under testing device. Ali methods presented satisfactory results, allowing establishing performance differences among tested units and the area validation by comparing to a standard device. The mass transfer water based and the gas flow head loss are non destructive methods. The results provided by the gas flow head loss method achieved a better level of resolution / Doutorado / Materiais e Processos de Fabricação / Doutor em Engenharia Mecânica
42

Descartova mechanistická fyziologie a Harveyho objev krevního oběhu / Descartes' Mechanistic Physiology and Harvey's Discovery of the Circulation of Blood

Čejka, Vojtěch January 2019 (has links)
The aim of this thesis is to show in what way the mechanistic philosophy of René Descartes allowed him to accept William Harvey's discovery of the circulation of the blood, while at the same time prevented him from accepting his explanation of the movement of the heart. In the introductory section we mention some of the basic notions concerning the state of natural philosophy in the second half of the 16th century which are closely related to the themes of the thesis. Both authors we are concerned with are also presented. The second, historicaly oriented section focuses on Aristotle's, Galen's and Harvey's opinions on the role and motion of the heart and blood in the human body. The aim is to describe how Harvey's 1628 treatise De motu cordis allowed to resolve the proliferating problems faced by the Galenist tradition in the 16th and the early 17th century. The third section presents the exposition of the introductory chapters of Descartes' 1633 treatise Le Monde in which he introduces the basic notions of his new mechanistic philosophy. Among these are the three types of particles, the plenist conception of the world, the omnipresence of circular motions and the relationship between God, natural laws and motion in the world. The fourth section is dedicated to Descartes' a Harvey's point of...
43

Desenvolvimento de uma interface de comunicação para determinação da difusividade térmica em função da temperatura, por termografia no infravermelho / Development of a communication interface to determinate the thermal diffusivity as a function of temperature by infrared thermography

CORREA, PAULO R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:41:14Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:34Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
44

Obtenção, caracterizações estruturais e atividade enzimática do sítio C-catalítico da enzima conversora de angiotensina I - região ALAsup(959) até SERsup(1066) / Obtaining, structural characterization and enzymatic activity of the C catalytic site of angiotensin convertin enzyme I ALA959 to SER1066 region

ELIAS, CAROLINE C. 17 December 2015 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-12-17T09:13:12Z No. of bitstreams: 0 / Made available in DSpace on 2015-12-17T09:13:12Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
45

Desenvolvimento de uma interface de comunicação para determinação da difusividade térmica em função da temperatura, por termografia no infravermelho / Development of a communication interface to determinate the thermal diffusivity as a function of temperature by infrared thermography

CORREA, PAULO R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:41:14Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:34Z (GMT). No. of bitstreams: 0 / O objetivo deste trabalho foi desenvolver um software, de fácil operação e eficiente, para determinar a difusividade térmica de biomateriais. A necessidade de se conhecer a difusividade térmica de materiais como, por exemplo, esmalte e dentina, é essencial para o estabelecimento de protocolos de utilização clínica laser, para evitar danos colaterais ao paciente. O software desenvolvido, denominado CZ ThermaDiff, baseia-se no processamento de imagens térmicas adquiridas por uma câmera termográfica no infravermelho (ThermaCam SC3000, FLIR System, EUA). Foi desenvolvido em ambiente LabView, o que permitiu criar um painel de controle de fácil operação, contendo apenas duas funções básicas (Start e Stop). O software arquiva os dados em formato de tabela contendo todas as medidas de difusividade térmica, suas médias para intervalos de 10 °C e suas respectivas temperaturas, para uma amostra. Foi observado, tanto para o esmalte quanto para a dentina, que os valores de difusividade não são constantes e aumentavam em função da temperatura. Os valores encontrados foram aplicados a um modelo de transferência de calor, simulando um dente molar humano com as seguintes estruturas: esmalte, dentina e polpa. O modelo baseia-se no método de resistores térmicos, sendo que para a polpa foi utilizado o modelo de difusão de calor, considerando a circulação sanguínea. Os valores de temperatura obtidos neste modelo teórico, utilizando difusividades dependentes da temperatura foram maiores que as obtidas com um valor constante de difusividade, medido à temperatura ambiente. Este fato realça a importância da mensuração da difusividade em função da temperatura e da interface desenvolvida neste trabalho. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
46

Obtenção, caracterizações estruturais e atividade enzimática do sítio C-catalítico da enzima conversora de angiotensina I - região ALAsup(959) até SERsup(1066) / Obtaining, structural characterization and enzymatic activity of the C catalytic site of angiotensin convertin enzyme I ALA959 to SER1066 region

ELIAS, CAROLINE C. 17 December 2015 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-12-17T09:13:12Z No. of bitstreams: 0 / Made available in DSpace on 2015-12-17T09:13:12Z (GMT). No. of bitstreams: 0 / A enzima conversora de angiotensina (ECA) catalisa a conversão de angiotensina I (Ang I) no vasoconstritor angiotensina II (Ang II) e hidrolisa a bradicinina (BK). ECA somática (sECA) possui dois domínios homólogos (N e C) que têm 60% de identidade. Embora estas duas regiões tenham homologia grande, o sítio catalítico C-domínio exibe uma atividade três vezes maior do que o N-domínio na hidrolise de Ang I in vivo. Este fato torna interessante o desenvolvimento de novos estudos de inibidores ou a melhoria dos já existentes. O objetivo deste estudo foi obter a região Ala959 até Ser1066 do Cdomínio da sECA (c-sECA), em uma estrutura conformacional semelhante à estrutura nativa. Nós amplificamos a sequência correspondente ao sítio catalítico da c-sECA com 324pb e clonamos esta sequência no vetor pET 28a(+). O segmento (nomeado de pET28_c-sECA) foi expresso em sistema bacteriano. A proteína foi expressa na forma solúvel e a purificação foi feita em uma única etapa utilizando a coluna de afinidade His-tag, a qual produziu a proteína pura. Análises estruturais por dicroísmo circular e fluorescência confirmaram que a proteína recombinante estava na conformação correta, e os ensaios de atividade mostraram que a c-sECA possui atividade enzimática e é inibida por lisinopril. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
47

Ensaios in vivo e avaliação clínica de bomba de sangue para circulação extracorpórea durante cirurgia cardíaca : spiral pump / In vivo tests and clinical evaluation of centrifugal blood pump for cardiopulmonary bypass during cardiac surgery : spiral pump

Silva, Cibele da 22 August 2018 (has links)
Orientadores: Cecília Amélia de Carvalho Zavaglia, Aron José Pazin de Andrade / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-22T16:21:16Z (GMT). No. of bitstreams: 1 Silva_Cibeleda_M.pdf: 8042828 bytes, checksum: f69ba730298b110aecb701c7d8d19cf6 (MD5) Previous issue date: 2013 / Resumo: Neste trabalho foram elaborados os métodos e realizados estudos In Vivo e Avaliação Clínica de uma Bomba de Sangue para Circulação Extracorpórea (CEC), durante Cirurgia Cardíaca, denominada Spiral Pump® (SP). Esses estudos foram realizados com o objetivo de avaliar o desempenho e segurança da bomba, finalizando assim o projeto e avaliando a SP como um produto em sua aplicação rotineira durante as cirurgias cardíacas. A SP utiliza, simultaneamente, dois princípios de bombeamento, o centrífugo e o axial, proporcionados por sua geometria cônica, visando aumentar a eficiência de bombeamento sem o aumento dos índices de destruição dos elementos figurados do sangue. O primeiro passo para avaliação In Vivo foi à elaboração de um protocolo para avaliação In Vivo animal e sua submissão a Comissão de Ética para Uso de Animais (CEUA) do Instituto Dante Pazzanese de Cardiologia (IDPC). As avaliações In Vivo consistiram em instalação normal da CEC, em animais suínos, utilizando a SP conectada a um módulo de acionamento e, para fins de comparação, foi realizado o mesmo procedimento com a Bio-Pump®. Foram realizados seis experimentos com a SP, sendo o primeiro considerado piloto, e três experimentos com a Bio-Pump®, com duração de seis horas cada. As observações realizadas pela equipe médica e pela perfusionista demonstraram grande semelhança de funcionamento entre as duas bombas, inclusive em relação a vibrações, ruídos e facilidade de utilização. As bombas foram comparadas em relação à medição do trauma, analisado a partir da evolução da hemoglobina livre no plasma (PFH). Analisando os resultados laboratoriais e de hemólise obtidos com a SP e a Bio-Pump®, pode-se verificar que não existem diferenças significativas entre elas. Com resultados satisfatórios nos ensaios In Vivo, a SP foi aprovada para Avaliação Clínica, realizada de acordo com a legislação vigente. Foi elaborado um Protocolo de Pesquisa Clínica que seguiu a Resolução ANVISA número 39 de 05 de junho de 2008, que estabelece requisitos para realização de pesquisa clínica no Brasil. Esse protocolo foi submetido ao Comitê de Ética em Pesquisa (CEP) do IDPC e ao Conselho Nacional de Ética em Pesquisa (CONEP). A pesquisa clínica foi realizada no Centro Cirúrgico do IDPC em um grupo de quarenta pacientes com indicação de cirurgia cardíaca com CEC, com ou sem cardioplegia, ambos os sexos, adultos, peso corporal mínimo de 50 kg. Durante a CEC, a SP substituiu as convencionais bombas de roletes no circuito de CEC. Todos os pacientes foram entrevistados e autorizaram a realização do estudo, assinando do Termo de Consentimento Livre e Esclarecido. Foram coletados dados comumente monitorados durante uma cirurgia cardíaca e foram realizados, nos períodos de pré e pós CEC, exames de Desidrogenase Láctica (U/L), Plaquetas (mil/mm3), Fibrinogênio (mg/dL), além de monitoração da hemólise através de fita de urianálise. Os procedimentos transcorreram de forma habitual, e os parâmetros mantiveram-se dentro do esperado para o estudo, demonstrando a eficiência e segurança da SP como bomba para circulação extracorpórea durante cirurgia cardíaca / Abstract: Were developed methods and studies In Vivo and clinical evaluation were conducted with a blood pump for cardiopulmonary bypass (CPB), during cardiac surgery, the Spiral Pump® (SP). These studies are designed to assess the performance and safety of SP, finalizing the project and evaluating the SP as a product in its routine application during heart surgeries. The SP uses simultaneously, two principles of pumping, axial and centrifugal, provided by its conical geometry, in order to increase pumping efficiency without increased levels of destruction of the figured elements from blood. First step for In Vivo evaluation was the development of a protocol for In Vivo experiments and its submission to the "Ethic Committee for Animal Use" of Institute Dante Pazzanese of Cardiology (IDPC). The In Vivo assessments consisted of normal installation of the CPB in pigs, using the SP connected to a driver console and, for comparison purposes, the same procedure was performed with Bio-Pump®. Six experiments were performed with SP and three experiments with Bio-Pump®, lasting six hours each. Observations made by medical team showed great similarity between two pumps, including characteristics of vibration and noise. Two pumps were compared concerning to measurement of trauma, through the evolution of plasma free hemoglobin (PFH) and the PFH variation (?PFH). Analyzing laboratory results and hemolysis, from In Vivo assays with SP and the Bio-Pump®, we can observe no significant differences between them. With satisfactory results from In Vivo assays, SP was approved for clinical evaluation, carried out in accordance with current legislation. A Clinical Research Protocol was elaborated following ANVISA (National Health Surveillance Agency) resolution number 39 of 2008, which establishes requirements for conducting clinical research in Brazil. This Protocol was submitted to the Ethic Committee Research of IDPC for review and subsequently to National Council of Ethics in Research. Clinical research was conducted at operating room of IDPC in a group of forty patients under cardiac surgery with CPB, both sexes, adults, minimum of 50 kg of body weight. During CPB, SP replaced conventional CPB roller pump. All patients were interviewed and had authorized this study, signing of consent form. Usually monitored data were collected during a heart surgery and additional examinations were carried out at periods of pre and post CEC such as: Lactic dehydrogenase exams (U/L), platelets (1000/mm3), Fibrinogen (mg/dL), as well as monitoring of hemolysis by urianalysis tape. All procedures were as usual way, and all parameters remained as expected for this study, demonstrating the performance and safety of SP as pump for CPB during heart surgery / Mestrado / Materiais e Processos de Fabricação / Mestra em Engenharia Mecânica
48

Circulatory and Respiratory Responses to Cycle Ergometry at Different Pedal Rates

Hernandez, Raymundo 05 1900 (has links)
The effects of moderate workload exercise at different pedal rates on circulatory and respiratory parameters were studied. Five subjects performed seven discontinuous constant-load cycle ergometer tests of 30 minutes duration at pedal rates of 40, 50, 60, 70, 80, 90 and 100 rpm. Oxygen uptake and carbon dioxide production were determined by standard open circuit spirometry, while heart rate was recorded by electrocardiograph. The CO₂ rebreathing procedure was administered during the exercise bout in order to determine cardiac output. Blood pressure was determined for each test, and total peripheral resistance was calculated. The findings indicate that progressive increases in pedal frequency during discontinuous constant-load cycle ergometry produce progressive increases in cardiovascular, respiratory and metabolic responses and a decrease in gross exercise mechanical efficiency. The results indicate that oxygen uptake, cardiac output, heart rate, ventilation and arterial-venous oxygen difference increases curvilinearly as pedal rate increases, possibly as a result of increases in recruitment of muscle fibers and/or muscle groups. These findings suggest that circulatory and respiratory responses are due to "central command" which sets the basic efferent response pattern. However, this effector pattern is modulated by afferent input originating from the legs during progressive increases in pedal rate.
49

The prevalence of high blood pressure amongst the University of Venda academic staff, South Africa

Madzaga, Thizwilondi 18 May 2017 (has links)
MPH / Department of Public Health / High blood pressure is a global public health problem. High blood pressure shows no signs or symptoms and it can only be detected through BP measurements by a health professionals. It’s a chronic condition which requires long term management. Poor control of high blood pressure can lead to complications and even death. The aim of the study was to determine the prevalence of high blood pressure among University of Venda academic staff. UNIVEN is situated in Thohoyandou, Vhembe District in Limpopo. A cross-sectional design was used. A modified WHO stepwise questionnaire for non-communicable diseases version 3.1 was used to collect data regarding demographic characteristics, BP status, and stress and lifestyle characteristics. Charts and graphs were used to present the results of the study. The Statistical Package of Social Sciences was used to analyse data. The Chi-square test was used to determine the association between blood pressure and risk factors. A total of 179 respondents were selected, their ages of were ranged from 22 to 68 years. Their blood pressure, weight and height of the participants were also measured. The prevalence of high blood pressure was 20%, while 46% were on prehypertension stage and about 34% had a normal BP. About 23% had been previously diagnosed with HBP, while about 90% were on treatment for high blood pressure. Only 13% had their BP under control. The prevalence of high blood pressure was associated with gender, family history, vegetable intake and diabetes. Department of Sports need to introduce sports among academic staff as a way of prevention and management of high blood pressure.
50

Contributory factors of noncompliance to treatment among patients diagnosed with hypertension in the Vhembe District of the Limpopo Province

Mashila, Vuledzani Sylvia 21 September 2018 (has links)
MCur / Department of Advanced Nursing Science / Noncompliance with antihypertensive treatment is a challenge for uncontrolled hypertension in both high income and middle income countries. Compliance to antihypertensive treatment and lifestyle modification plays a significant role in the control of hypertension and reduces the cardiovascular morbidity and mortality rate. The purpose of this study was to explore and describe contributory factors of noncompliance to treatment among patients diagnosed with hypertension in the Vhembe District of the Limpopo Province The study was conducted at the regional Hospital and nine Primary Health Care facilities in the rural community in the Vhembe District of the Limpopo Province. The study population consisted of those patients diagnosed with hypertension receiving treatment from the ten sampled health facilities. In this study, the target population included 134 noncompliant patients diagnosed with hypertension taking treatment at the sampled health facilities. This study used simple random sampling. The instrument used for data collection was self-administered questionnaire. Data was analysed using the Statistical Package for Social Sciences. The results of this current study reveal that participants aged 40 years and above (85.1%) were noncompliant to treatment compared to those of the same or less than 40 years old (14.9%). Also, it indicated that females were more frequently noncompliant to treatment (73.1%) compared to males (26.9%), which was statistically significant. The study revealed that the unmarried participants (64.9%) were more non-compliant with treatment when compared to the married participants (35.1%). The current findings demonstrate that 40.3% of noncompliant participants mentioned the reason being that they were feeling well. Various factors related to participants’ noncompliance with their antihypertensive treatment and lifestyle modification regimen were described. Health education should cover the nature of hypertension specifically emphasising causes, severity and potential complications. / NRF

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