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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.
1

MIMO active vibration control of magnetically suspended flywheels for satellite IPAC service

Park, Junyoung 15 May 2009 (has links)
Theory and simulation results have demonstrated that four, variable speed flywheels could potentially provide the energy storage and attitude control functions of existing batteries and control moment gyros (CMGs) on a satellite. Past modeling and control algorithms were based on the assumption of rigidity in the flywheel’s bearings and the satellite structure. This dissertation provides simulation results and theory which eliminates this assumption utilizing control algorithms for active vibration control (AVC), flywheel shaft levitation and integrated power transfer and attitude control (IPAC) that are effective even with low stiffness active magnetic bearings (AMB), and flexible satellite appendages. The flywheel AVC and levitation tasks are provided by a multi input multi output (MIMO) control law that enhances stability by reducing the dependence of the forward and backward gyroscopic poles with changes in flywheel speed. The control law is shown to be effective even for (1) Large polar to transverse inertia ratios which increases the stored energy density while causing the poles to become more speed dependent and, (2) Low bandwidth controllers shaped to suppress high frequency noise. These two main tasks could be successfully achieved by MIMO (Gyroscopic) control algorithm, which is unique approach. The vibration control mass (VCM) is designed to reduce the vibrations of flexible appendages of the satellite. During IPAC maneuver, the oscillation of flywheel spin speeds, torque motions and satellite appendages are significantly reduced compared without VCM. Several different properties are demonstrated to obtain optimal VCM. Notch, band-pass and low-pass filters are implemented in the AMB system to reduce and cancel high frequency, dynamic bearing forces and motor torques due to flywheel mass imbalance. The transmitted forces and torques to satellite are considerably decreased in the present of both notch and band-pass filter stages. Successful IPAC simulation results are presented with a 12 [%] of initial attitude error, large polar to transverse inertia ratio (IP / IT), structural flexibility and unbalance mass disturbance. Two variable speed control moment gyros (VSCMGs) are utilized to demonstrate simultaneous attitude control and power transfer instead of using four standard pyramid configurations. Launching weights including payload and costs can be significantly reduced.
2

Clonagem molecular do gene ipaC de Shigella sp e estudo da expressão por Lactococcus lactis / Molecular cloning and expression analysis in Lactococcus lactis of ipaC gene from Shigella sp

Mobilon, Cristiane, 1982- 21 August 2018 (has links)
Orientadores: Wanderley Dias da Silveira, Eliana Guedes Stehling / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-21T01:02:36Z (GMT). No. of bitstreams: 1 Mobilon_Cristiane_D.pdf: 11609484 bytes, checksum: 06504829a16dd9fe15e1e7aff6ed5392 (MD5) Previous issue date: 2012 / Resumo: A shigelose, uma infecção intestinal grave, causada por bactérias Gram-negativas pertencentes ao gênero Shigella, é uma patologia com incidência significativa, principalmente em países em desenvolvimento, onde ocorrem 99% dos casos relatados, sendo que, 69% deles acometem crianças menores de 5 anos de idade. A alta incidência de Shigella em países em desenvolvimento é, geralmente, atribuída à falta de saneamento básico, condições de higiene inadequadas, subnutrição e alto custo dos antimicrobianos. O modo predominante de transmissão ocorre por via fecal-oral. Os mecanismos de patogenicidade descritos para as diferentes espécies de Shigella incluem numerosos genes de virulência, sendo a maioria encontrada em um plasmídio (pINV) de 220 kb. O plasmídio pINV de S. flexneri codifica 2 operons cruciais para seu fenótipo invasivo: o operon ipa e o operon mxi-spa. O operon ipa codifica os antígenos plasmidiais de invasão denominados IpaA, IpaB, IpaC e IpaD, os quais são efetores para o processo de invasão bacteriana. O operon mxi-spa juntamente com as proteínas IpaB, IpaC e IpaD são essenciais para a invasão in vitro de células epiteliais. Sabe-se, também, que essas proteínas, ou antígenos plasmidiais de invasão, podem ser altamente imunogênicos. Neste trabalho, clonou-se o gene ipaC no vetor pET28a para expressão em Escherichia coli e em vetores constitutivos para bactérias lácticas com a finalidade de se verificar a capacidade imunogênica da proteína expressa por este gene. Além disso, verificou-se que os anticorpos produzidos pela resposta à proteína IpaC foram capazes de inibir a adesão e invasão de Shigella flexneri em culturas celulares cultivadas in vitro confirmando, assim, a importância dessa proteína no processo invasivo da bactéria e seu possível uso no desenvolvimento de futuras vacinas a serem usadas contra a shigelose / Abstract: Shigellosis is a severe intestinal infection caused by Gram-negative bacteria which belongs to the genus Shigella. It is a pathology with high incidence and it is known that 99% of cases occur in underdevelopment countries. Among these cases, 69% of them affect children under 5 years old. The high incidence of Shigella in underdevelopment countries, is mainly atribbuted to substandard hygiene, unsafe water supplies, subnutrition and antibiotic high cost. The predominant mode of transmission is by fecal-oral contact. The pathogenicity mechanisms described for Shigella species include several virulence genes, most of them been encoded in a plasmid (pINV) with 220 kb. This plasmid encodes 2 important operons which are essential for the invasive phenotype: the operon ipa and the operon mxi-spa. The ipa operon encodes the invasion plasmid antigens called IpaA, IpaB, IpaC and IpaD, which are effector proteins required for the bacteria invasion process. The mxi-spa operon together with IpaB, IpaC and IpaD are essential to epithelial in vitro cell invasion. It is also known that these proteins or invasion plasmid antigens may be highly immunogenic. During the development of this work, ipaC gene was cloned in the plasmidial vector pET28a for expression in Escherichia coli and in constitutive vectors for lactic acid bacteria to prove its immunogenic importance. Furthermore it was verified that the antibodies produced in response to IpaC protein were able to inhibit Shigella flexneri adhesion and invasion in in vitro cultured cells, confirming its important hole in bacteria invasion process and its possible usage in vaccine development against shigellosis / Doutorado / Genetica de Microorganismos / Doutor em Genetica e Biologia Molecular
3

Investigation of the Molecular Mechanisms of the Shigella Type III Secretion System Tip Complex

Bernard, Abram R. 01 December 2018 (has links)
Shigella are bacteria that are responsible for millions of infections and hundreds of thousands of deaths every year. The emergence of antibiotic resistant Shigella adds to the potentially devastating effect that these bacteria can have on human health. Shigella flexneri utilize specialized molecular machinery called the Type III secretion system to infect humans and cause disease. Research of this machinery promises to provide the knowledge, tools, and direction for the development of new avenues to combat shigellosis. This dissertation presents studies of two Shigella proteins, invasion plasmid antigens C and D (IpaC and IpaD). These proteins are part of a syringe and needle like protein structure that allows Shigella to secrete proteins directly into the host that hijack host cells to benefit support Shigella infections. IpaC and IpaD are part of a protein tip complex that is directly involved in these Shigella-host (e.g. human) interactions. We have advanced the biochemical tools for the in vitro study of IpaC by utilizing a new way to isolate it. This purification methodology allowed us to look at one of IpaC’s main roles, to interact with the host cell membranes. We examined IpaC’s role and tried to identify the parts of IpaC responsible for some specific interactions. We found that the parts of IpaC we believed were responsible were not but that the composition of the membrane IpaC is interacting with is more important than we previously believed. Finally, we examined a rare part of IpaD structure to determine its role. We determined that this rare feature is required for IpaD to sense Shigella’s host environment and prepare the bacteria to infect, making a promising target for anti-infective treatments against Shigella infections. Our findings advance the understanding of key molecular mechanisms that are required for Shigella virulence. We expect that our findings will aid future researchers as the pursuit for new treatments for shigellosis continues.
4

Comparação entre diferentes instrumentos para avaliação do nível de atividade física em adultos

Ribeiro, Sandro Roberto Santos 15 March 2010 (has links)
Made available in DSpace on 2015-02-04T21:42:08Z (GMT). No. of bitstreams: 1 Sandro Ribeiro.pdf: 374580 bytes, checksum: e3626dd188796766bd1d733535ec2a81 (MD5) Previous issue date: 2010-03-15 / A atenção dirigida ao papel de fatores comportamentais relacionados à saúde e bem estar dos seres humanos vem aumentando nos últimos anos. Por mais de quatro décadas, questionários têm sido utilizados objetivando dimensionar o nível de atividade física em populações adultas e a promoção de políticas de incentivo a prática destas atividades. A produção de informações científicas sobre as características dos diferentes instrumentos empregados para mensurar o nível de atividade física em populações é relevante para subsidiar pesquisadores na escolha da ferramenta mais apropriada para cada investigação e comparar os resultados com o consumo máximo de oxigênio. Este trabalho teve como objetivo a aplicação de diferentes ferramentas de medida do nível de atividade física em adultos comparando entre si os resultados obtidos. Foi realizado um estudo descritivoanalítico do tipo observacional empregando dois diferentes instrumentos de mensuração do nível de atividade física. Os instrumentos foram aplicados num único momento, caracterizando assim um estudo do tipo transversal. A amostra populacional, composta por 20 profissionais da Universidade Monte Serrat, foi submetida à aplicação de dois questionários que avaliam atividade física e a um teste de potência aeróbia máxima. De acordo com os resultados obtidos neste trabalho o questionário IPAQ foi o mais satisfatório para avaliar o nível de atividade física em adultos, quando comparado com o questionário QAFH.
5

Relação entre atividades de vida diária, capacidade funcional e gravidade da doença pulmonar obstrutiva crônica

Bittencourt, Darlene Costa de January 2009 (has links)
Introdução: A doença pulmonar obstrutiva crônica (DPOC) se caracteriza por limitação crônica ao fluxo aéreo, dispneia e redução da capacidade de exercício. Na doença avançada o desempenho das atividades de vida diária (AVDs) pode estar comprometido. Objetivo: Estudar a relação entre atividades de vida diária, capacidade funcional e gravidade em pacientes com DPOC. Material e Métodos: Estudo transversal, com realização de dois questionários (London Chest Activity of Daily Living - LCADL e International Physical Activity Questionnaire – IPAQ), exames de função pulmonar e teste de caminhada de 6 minutos (TC6m). A dispneia foi avaliada pela escala Modified Medical Research Council (MMRC) e a gravidade da doença pelo VEF1 e pelo índice BODE. Resultados: Dos 95 pacientes avaliados, 62 eram homens (65,3%). O VEF1 médio foi de 1,05±0,43 litros (DP), 40,7±15,9% do previsto. A distância percorrida no TC6m foi de 386±115 m. A média do MMRC foi de 2,5±1,3, do índice BODE 4,3±2,3, do LCADL foi de 23,4±12,2 e do IPAC 837 (0 - 3.493). Em 47,4% dos pacientes o nível de atividade física medido pelo IPAC foi baixo. A pontuação total do LCADL mostrou correlação negativa com a distância caminhada (r=-0,51; p<0,001) e positiva com o MMRC (r=0,50; p<0,001) e com o índice BODE (r=0,46; p<0,001). A melhor correlação entre IPAC e índice BODE e domínios do LCADL foi com o lazer. A associação do LCADL com as demais variáveis funcionais pulmonares foi fraca ou inexistente. Conclusões: Nosso estudo demonstrou uma importante redução do nível de atividade física em pacientes com DPOC e um impacto significativo da doença sobre as AVDs. Houve uma correlação moderada entre o escore total do LCADL e a distância caminhada, a dispneia e o índice BODE. / Introduction: Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation, dyspnea, and reduced exercise capacity. In advanced disease, the performance of activities in daily life (ADLs) can be reduced. Aim: To investigate the relationship between ADLs, functional capacity and disease severity in patients with COPD. Material and Methods: Cross-sectional study. Two questionnaires (London Chest Activity of Daily Living - LCADL and International Physical Activity Questionnaire – IPAQ), lung function testing and six-minute walk test (SMWT) were performed. Dyspnea was evaluated by the Modified Medical Research Council (MMRC) scale and the COPD severity by FEV1 and BODE index. Results: Out of the 95 patients studied, 62 were men (65.3%). Mean FEV1 was 1.05±0.43 liters (SD), 40.7±15.9 % of predicted. The walked distance on SMWT was 386±115m. Mean MMRC value was 2.5±1.3, BODE index was 4.3±2.3, LCADL score was 23.4±12.2 and IPAC was 837 (0 - 3.493). In 47.4% of patients the activity level evaluated by IPAC was low. There was negative correlation between total score of LCADL and walked distance (r=-0.51; p<0.001) and positive with MMRC (r=0.50; p<0.001) and BODE index (r=0.46; p<0.001). The best correlation scores of IPAC and BODE index were seen with the leisure time domain of LCADL. Associations of LCADL with other lung function variables were weak or inexistent. Conclusions: Our study demonstrated an important reduction on physical activity level in COPD patients and a significant impact of the disease on ADLs. There was a moderate correlation between total score of LCADL and walked distance, dyspnea and BODE index.
6

Relação entre atividades de vida diária, capacidade funcional e gravidade da doença pulmonar obstrutiva crônica

Bittencourt, Darlene Costa de January 2009 (has links)
Introdução: A doença pulmonar obstrutiva crônica (DPOC) se caracteriza por limitação crônica ao fluxo aéreo, dispneia e redução da capacidade de exercício. Na doença avançada o desempenho das atividades de vida diária (AVDs) pode estar comprometido. Objetivo: Estudar a relação entre atividades de vida diária, capacidade funcional e gravidade em pacientes com DPOC. Material e Métodos: Estudo transversal, com realização de dois questionários (London Chest Activity of Daily Living - LCADL e International Physical Activity Questionnaire – IPAQ), exames de função pulmonar e teste de caminhada de 6 minutos (TC6m). A dispneia foi avaliada pela escala Modified Medical Research Council (MMRC) e a gravidade da doença pelo VEF1 e pelo índice BODE. Resultados: Dos 95 pacientes avaliados, 62 eram homens (65,3%). O VEF1 médio foi de 1,05±0,43 litros (DP), 40,7±15,9% do previsto. A distância percorrida no TC6m foi de 386±115 m. A média do MMRC foi de 2,5±1,3, do índice BODE 4,3±2,3, do LCADL foi de 23,4±12,2 e do IPAC 837 (0 - 3.493). Em 47,4% dos pacientes o nível de atividade física medido pelo IPAC foi baixo. A pontuação total do LCADL mostrou correlação negativa com a distância caminhada (r=-0,51; p<0,001) e positiva com o MMRC (r=0,50; p<0,001) e com o índice BODE (r=0,46; p<0,001). A melhor correlação entre IPAC e índice BODE e domínios do LCADL foi com o lazer. A associação do LCADL com as demais variáveis funcionais pulmonares foi fraca ou inexistente. Conclusões: Nosso estudo demonstrou uma importante redução do nível de atividade física em pacientes com DPOC e um impacto significativo da doença sobre as AVDs. Houve uma correlação moderada entre o escore total do LCADL e a distância caminhada, a dispneia e o índice BODE. / Introduction: Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation, dyspnea, and reduced exercise capacity. In advanced disease, the performance of activities in daily life (ADLs) can be reduced. Aim: To investigate the relationship between ADLs, functional capacity and disease severity in patients with COPD. Material and Methods: Cross-sectional study. Two questionnaires (London Chest Activity of Daily Living - LCADL and International Physical Activity Questionnaire – IPAQ), lung function testing and six-minute walk test (SMWT) were performed. Dyspnea was evaluated by the Modified Medical Research Council (MMRC) scale and the COPD severity by FEV1 and BODE index. Results: Out of the 95 patients studied, 62 were men (65.3%). Mean FEV1 was 1.05±0.43 liters (SD), 40.7±15.9 % of predicted. The walked distance on SMWT was 386±115m. Mean MMRC value was 2.5±1.3, BODE index was 4.3±2.3, LCADL score was 23.4±12.2 and IPAC was 837 (0 - 3.493). In 47.4% of patients the activity level evaluated by IPAC was low. There was negative correlation between total score of LCADL and walked distance (r=-0.51; p<0.001) and positive with MMRC (r=0.50; p<0.001) and BODE index (r=0.46; p<0.001). The best correlation scores of IPAC and BODE index were seen with the leisure time domain of LCADL. Associations of LCADL with other lung function variables were weak or inexistent. Conclusions: Our study demonstrated an important reduction on physical activity level in COPD patients and a significant impact of the disease on ADLs. There was a moderate correlation between total score of LCADL and walked distance, dyspnea and BODE index.
7

Relação entre atividades de vida diária, capacidade funcional e gravidade da doença pulmonar obstrutiva crônica

Bittencourt, Darlene Costa de January 2009 (has links)
Introdução: A doença pulmonar obstrutiva crônica (DPOC) se caracteriza por limitação crônica ao fluxo aéreo, dispneia e redução da capacidade de exercício. Na doença avançada o desempenho das atividades de vida diária (AVDs) pode estar comprometido. Objetivo: Estudar a relação entre atividades de vida diária, capacidade funcional e gravidade em pacientes com DPOC. Material e Métodos: Estudo transversal, com realização de dois questionários (London Chest Activity of Daily Living - LCADL e International Physical Activity Questionnaire – IPAQ), exames de função pulmonar e teste de caminhada de 6 minutos (TC6m). A dispneia foi avaliada pela escala Modified Medical Research Council (MMRC) e a gravidade da doença pelo VEF1 e pelo índice BODE. Resultados: Dos 95 pacientes avaliados, 62 eram homens (65,3%). O VEF1 médio foi de 1,05±0,43 litros (DP), 40,7±15,9% do previsto. A distância percorrida no TC6m foi de 386±115 m. A média do MMRC foi de 2,5±1,3, do índice BODE 4,3±2,3, do LCADL foi de 23,4±12,2 e do IPAC 837 (0 - 3.493). Em 47,4% dos pacientes o nível de atividade física medido pelo IPAC foi baixo. A pontuação total do LCADL mostrou correlação negativa com a distância caminhada (r=-0,51; p<0,001) e positiva com o MMRC (r=0,50; p<0,001) e com o índice BODE (r=0,46; p<0,001). A melhor correlação entre IPAC e índice BODE e domínios do LCADL foi com o lazer. A associação do LCADL com as demais variáveis funcionais pulmonares foi fraca ou inexistente. Conclusões: Nosso estudo demonstrou uma importante redução do nível de atividade física em pacientes com DPOC e um impacto significativo da doença sobre as AVDs. Houve uma correlação moderada entre o escore total do LCADL e a distância caminhada, a dispneia e o índice BODE. / Introduction: Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation, dyspnea, and reduced exercise capacity. In advanced disease, the performance of activities in daily life (ADLs) can be reduced. Aim: To investigate the relationship between ADLs, functional capacity and disease severity in patients with COPD. Material and Methods: Cross-sectional study. Two questionnaires (London Chest Activity of Daily Living - LCADL and International Physical Activity Questionnaire – IPAQ), lung function testing and six-minute walk test (SMWT) were performed. Dyspnea was evaluated by the Modified Medical Research Council (MMRC) scale and the COPD severity by FEV1 and BODE index. Results: Out of the 95 patients studied, 62 were men (65.3%). Mean FEV1 was 1.05±0.43 liters (SD), 40.7±15.9 % of predicted. The walked distance on SMWT was 386±115m. Mean MMRC value was 2.5±1.3, BODE index was 4.3±2.3, LCADL score was 23.4±12.2 and IPAC was 837 (0 - 3.493). In 47.4% of patients the activity level evaluated by IPAC was low. There was negative correlation between total score of LCADL and walked distance (r=-0.51; p<0.001) and positive with MMRC (r=0.50; p<0.001) and BODE index (r=0.46; p<0.001). The best correlation scores of IPAC and BODE index were seen with the leisure time domain of LCADL. Associations of LCADL with other lung function variables were weak or inexistent. Conclusions: Our study demonstrated an important reduction on physical activity level in COPD patients and a significant impact of the disease on ADLs. There was a moderate correlation between total score of LCADL and walked distance, dyspnea and BODE index.
8

Univerzální linuxový server pro malé a střední firmy umožňující jednoduchý dohled nad sítí / Universal linux server for small and medium companies enabling simple network control

Juřena, Stanislav January 2008 (has links)
The main object of this thesis was to design a computer network for small and medium companies which will be made among others from network server providing simple network control. The next task was to provide internet connection to subscribers of local area network, their security and access to common services. There had been discussed the choice of distribution of Linux operation system with regarding to demanded services, stability and long lasting operation in theoretical part. One part of the work is a theoretic preliminary to separate services, to the purpose of their using and to their weaknesses. The practical part deals with an installation and configuration of Debian operating system, launching the base services and the setting of selected monitoring programs.

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