Infecções pulmonares de potros jovens por Rhodococcus equi resultam em grave pneumonia levando à morte um grande número de animais todos os anos. Até o momento não há nenhuma vacina aceita globalmente para a prevenção da rodococose equina. O único tratamento preconizado é baseado em antibioticoterapia, porém os protocolos clínicos são longos, de alto custo, com efeitos colaterais e tem favorecido a seleção de cepas resistentes aos antibióticos. Diversas estratégias no desenvolvimento de uma vacina segura e eficiente contra a rodococose foram propostas, porém, não induziram um efeito protetor considerável. O principal fator de virulência do R. equi descrito e amplamente estudado é a proteína vapA, no entanto, outras proteínas localizadas na ilha de patogenicidade estão presentes em amostras de R. equi virulento extraídos de animais infectados. Trabalhos recentes têm demonstrado a presença do gene vapG em todas as cepas virulentas e este gene é altamente expresso quando a bactéria reside no interior de macrófagos, tornando-o um possível alvo vacinal. Nosso grupo já possui experiência prévia no uso de linhagem de Salmonella enterica Typhimurium atenuada carreando a proteína vapA. Baseado nos resultados positivos obtidos, foi construída uma linhagem atenuada de S. enterica Typhimurium 3987 expressando a proteína vapG. A administração desta linhagem em camundongos foi capaz de induzir proteção contra R. equi virulento. Os resultados observados foram a colonização e persistência da Salmonella nos órgãos alvo, a redução da carga bacteriana de R. equi, e a indução de um perfil imune protetor semelhante ao observado em animais adultos resistentes. Observou-se o aumento da produção de IL-12p70 e IFN-, alem da presença de níveis aumentados de IL-4 e a redução dos níveis de TNF-. Observou-se também o aumento na subpopulação de células T auxiliares (CD4+) com perfil de memória, além de aumento na população de linfócitos B totais quando comparado aos grupos controles. Este conjunto de resultados indica que a imunização com Salmonella enterica Typhimurium expressando a proteína vapG gera uma resposta imune celular eficiente tornando esta linhagem uma possível candidata a vetor vacinal. Alem disso, sugere que outros antígenos do R. equi podem ser / Pulmonary infections in young foals by Rhodococcus equi result in severe pneumonia, leading to death a large number of animals every year. There is no globally accepted vaccine for the prevention of equine rhodococosis so far. To date, the only acceptable treatment is based on antibiotics, but the clinical protocols are long lasting, expensive, having side effects and favoring the emergence of drug resistant strains. Several strategies for developing a safe and effective vaccine against rhodococosis have been proposed, however, none has induced a significant protective effect. The main virulence factor of R. equi described and extensively studied is the protein vapA, although other proteins encoded by genes in pathogenicity islands are detected in samples of virulent R. equi, isolated from infected animals. Recent works have demonstrated that the vapG gene is present in all virulent strains, and that this gene is highly expressed when bacteria reside within macrophages, making it a potential vaccine target. Our group has already been working with an attenuated Salmonella enterica Typhimurium strain expressing the VapA protein. Even though our results were very promising, we decided to construct a second vaccine strain expressing the VapG protein. Based on the positive results, it was constructed an attenuated strain of S. enterica Typhimurium 3987 expressing the vapG protein. Interestingly, the VapG-expressing strain induced protection against virulent R. equi in mouse model of infection. We could observe colonization and persistence of Salmonella vaccine cells in target organs, with reduction of bacterial loads of R. equi and induction of a protective immune profile similar to that seen in resistant adult animals. We could also observe increased production of IL-12p70 and IFN- in addition to the presence of increased levels of IL-4 and reduced levels of TNF-. Moreover, we detected an increase in the subpopulation of T helper cells (CD4), with a profile of memory, as well as in the population of B lymphocytes, when compared to control groups. This set of results shows that immunization with Salmonella enterica Typhimurium expressing the VapG protein raises an efficient cellular immune response, making this strain a potential candidate for vaccine vector. Furthermore, this work suggests that other R. equi antigens may be taken into account for vaccine construction, besides the VapA protein utilized in the majority of studies.

Infecções pulmonares de potros jovens por Rhodococcus equi resultam em grave pneumonia levando à morte um grande número de animais todos os anos. Até o momento não há nenhuma vacina aceita globalmente para a prevenção da rodococose equina. O único tratamento preconizado é baseado em antibioticoterapia, porém os protocolos clínicos são longos, de alto custo, com efeitos colaterais e tem favorecido a seleção de cepas resistentes aos antibióticos. Diversas estratégias no desenvolvimento de uma vacina segura e eficiente contra a rodococose foram propostas, porém, não induziram um efeito protetor considerável. O principal fator de virulência do R. equi descrito e amplamente estudado é a proteína vapA, no entanto, outras proteínas localizadas na ilha de patogenicidade estão presentes em amostras de R. equi virulento extraídos de animais infectados. Trabalhos recentes têm demonstrado a presença do gene vapG em todas as cepas virulentas e este gene é altamente expresso quando a bactéria reside no interior de macrófagos, tornando-o um possível alvo vacinal. Nosso grupo já possui experiência prévia no uso de linhagem de Salmonella enterica Typhimurium atenuada carreando a proteína vapA. Baseado nos resultados positivos obtidos, foi construída uma linhagem atenuada de S. enterica Typhimurium 3987 expressando a proteína vapG. A administração desta linhagem em camundongos foi capaz de induzir proteção contra R. equi virulento. Os resultados observados foram a colonização e persistência da Salmonella nos órgãos alvo, a redução da carga bacteriana de R. equi, e a indução de um perfil imune protetor semelhante ao observado em animais adultos resistentes. Observou-se o aumento da produção de IL-12p70 e IFN-, alem da presença de níveis aumentados de IL-4 e a redução dos níveis de TNF-. Observou-se também o aumento na subpopulação de células T auxiliares (CD4+) com perfil de memória, além de aumento na população de linfócitos B totais quando comparado aos grupos controles. Este conjunto de resultados indica que a imunização com Salmonella enterica Typhimurium expressando a proteína vapG gera uma resposta imune celular eficiente tornando esta linhagem uma possível candidata a vetor vacinal. Alem disso, sugere que outros antígenos do R. equi podem ser / Pulmonary infections in young foals by Rhodococcus equi result in severe pneumonia, leading to death a large number of animals every year. There is no globally accepted vaccine for the prevention of equine rhodococosis so far. To date, the only acceptable treatment is based on antibiotics, but the clinical protocols are long lasting, expensive, having side effects and favoring the emergence of drug resistant strains. Several strategies for developing a safe and effective vaccine against rhodococosis have been proposed, however, none has induced a significant protective effect. The main virulence factor of R. equi described and extensively studied is the protein vapA, although other proteins encoded by genes in pathogenicity islands are detected in samples of virulent R. equi, isolated from infected animals. Recent works have demonstrated that the vapG gene is present in all virulent strains, and that this gene is highly expressed when bacteria reside within macrophages, making it a potential vaccine target. Our group has already been working with an attenuated Salmonella enterica Typhimurium strain expressing the VapA protein. Even though our results were very promising, we decided to construct a second vaccine strain expressing the VapG protein. Based on the positive results, it was constructed an attenuated strain of S. enterica Typhimurium 3987 expressing the vapG protein. Interestingly, the VapG-expressing strain induced protection against virulent R. equi in mouse model of infection. We could observe colonization and persistence of Salmonella vaccine cells in target organs, with reduction of bacterial loads of R. equi and induction of a protective immune profile similar to that seen in resistant adult animals. We could also observe increased production of IL-12p70 and IFN- in addition to the presence of increased levels of IL-4 and reduced levels of TNF-. Moreover, we detected an increase in the subpopulation of T helper cells (CD4), with a profile of memory, as well as in the population of B lymphocytes, when compared to control groups. This set of results shows that immunization with Salmonella enterica Typhimurium expressing the VapG protein raises an efficient cellular immune response, making this strain a potential candidate for vaccine vector. Furthermore, this work suggests that other R. equi antigens may be taken into account for vaccine construction, besides the VapA protein utilized in the majority of studies.

Nowadays, with the development of electronic and communication technologies, more and more low-cost vehicles such as small, light-weight aircraft are widely applied in all kinds of fields. Ground Station is an essential part of low cost vehicles for the operator to control and monitor the vehicles. In this thesis, Ground Station Display and Flight Management System for Low-Cost Vehicles have been developed.The major objective of this project is to design an intuitive and easy operative Human Machine Interface for displaying and monitoring the flight data and traffic information on ground. Meanwhile, a Graphic User Interface for the Flight Management System has been developed for realizing the waypoints input and flight plan for the vehicles. To fulfill this task, a low-cost hardware and software architecture is presented. Moreover, some COTS tools such as VAPS and MATLAB are applied for the software development because of their Object-Oriented and Rapid Prototype design methods. At the end of project, simulation has been done for the display HMI to test the behaviours of objects and the impacts of display. The trajectory simulation of flight management control panel is also implemented to test the waypoints creation, trajectory generation and smoothing.

In this thesis, the concept of virtual reality has been elaborated in the context of games, industrial design and manufacturing. The main purpose of this master’s thesis is to create a virtual environment for games that are near to the reality and according to the human nature through aspects like better interface, simulation, lights, shadow effects and their types. The importance of these aspects regarding realistic virtual environment is complemented through the comparison between two environments i.e. desktop and CAVE on a flight simulation program.

Background: The Vaal Triangle is an area generally associated with a number of harmful determinants of health since it houses diverse industrial processes and industrial development in South Africa, hence being categorised as an outdoor air pollution priority area in 2006. Method: A cross-sectional inter-comparative study to the 1990 Vaal Triangle Air Pollution and Health Study (VAPS) was conducted in 2010. The main objectives of this study were to measure the prevalence of upper and lower respiratory illnesses of 10-year-old children in 2010 and compare those findings to the 1990 study, and lastly to identify risk and protective factors for respiratory illnesses in 1990 and in 2010. In addition, the association between exposure factors (risk and protective factors) that are sources of indoor air pollution and factors related to diet and household living conditions and their associations with upper and lower respiratory health illnesses in 1990 and 2010 was determined. Results and Discussion: The prevalence of the respiratory health outcomes in the 1990 study and 2010 study cannot be compared directly since a 1-year prevalence was determined in 1990 and a 6-month prevalence in 2010. Throughout the dissertation this should be kept in mind. The change in prevalence of a respiratory health outcome observed in 1990 and in 2010 is just an indication of the possible change. The 1990 1-year prevalence and the 2-week 2010 prevalence of asthma were the same in the two study populations (i.e. 12%). The 6-month prevalence of sinusitis, bronchitis and pneumonia in 2010 was lower when compared to the yearly prevalence of these illnesses in the 1990 study. On completion of the multivariate analyses, in 1990 study, the use of a gas heater acted as a risk factor for pneumonia (a lower respiratory illness), with a odds ratio of 3.67 (1.15-11.71) and a p-value of 0.03, whilst environmental tobacco smoke within the household was protective of hay fever and sinusitis (upper respiratory illnesses). In the 2010 study, the consumption of chicken and/or fish and fruit at least three times a week was protective of bronchitis (with odds ratios of 0.23 and 0.26 respectively). Conclusion and Recommendations: It is not certain whether the change in the respiratory health status of 10-year-olds living in the Vaal Triangle is real as the prevalence of health outcomes in the two studies cannot be compared directly to one another due to the differences in prevalence time periods in the two studies. Nevertheless, a statistically significant change was observed in the prevalence of sinusitis, earache, bronchitis, and pneumonia between the two study populations. It is imperative to have a study protocol; this ensures all levels of measure are consistent in both studies and leads to a dataset of high quality. There is also a need for more analytical epidemiological studies (i.e. cohort, time-series, case-crossover and panel studies) to be done in South Africa, addressing indoor and outdoor air pollution and respiratory health. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / School of Health Systems and Public Health (SHSPH) / unrestricted