Rheumatoid arthritis (RA) is a chronic inflammatory disease mediated, in part, by pro-inflammatory cytokines such a sI L- I P, TNFa andI L-6. Many factors may contribute to cytokine imbalances in this disease, for example, biochemical modulation of PBMCsa ndt heir membranes A. key membrane proteini s the Na/KATPase( sodium pump) responsible for ionic homeostasis Sodiump ump activity on rheumatoid PBMCsw as found to be markedly depressed when compared with healthy control cells possibly through an oxidative mechanism. Inhibition of the sodium pump by a cardiac glycoside inhibitor, ouabain, transiently upregulated[N a'ji levels and rapidly induced IL-10 and TNFa mRNA and protein in human PBMCs. In contrast, IL-6 production was significantly depressed. The sodium ionophore, monensin, caused a similar Na-dependent cytokine response to that of ouabain. This cytokine profile however, was reversed when studying rheumatoids ynovial fibroblasts where ouabain induced I L-6; IL- I and TNFa, on the other hand, were not expressed. An elevation in intracellulars odiumc an causea secondary rise in intracellular calcium levels through the action of a Na/Ca2+ exchanger. In studies using the calcium ionophore, A23187, it was observed that an elevation in [Ca 2+]i brought aboutt he induction of IL- IP and TNF(xi n PBMCs with a corresponding repression of IL-6 production. The data obtained in this study suggest that impaired N a/K-ATPase activity in rheumatoid cells, through elevations in intracellular cation levels, might help promote over-production of IL- IP and TNF(x by monocytes and IL-6 by synovial fibroblasts. This pattern of cytokine production conforms to that observed in rheumatoid synovial tissue in situ, thus supporting a role for this biochemical defect in contributing to the perpetuation of the chronic inflammatory state.

This thesis is an analysis of the simulated performance of two indirect heat pump assisted solar domestic hot water (i-HPASDHW) systems compared to two base systems: an electric domestic hot water (DHW) system and a traditional solar domestic hot water (SDHW) system. In this study, the four systems of interest were modeled in the TRNSYS software and simulated for a year in order to compare their performances. All of the systems had the same load profile and aimed to deliver domestic hot water at a constant temperature. This insured that each system delivered approximately the same amount of energy for the simulated period, thereby creating a common basis for comparison. The heat pump was introduced into the system configuration in an attempt to further improve the performance. Theoretically, the heat pump should send colder fluid to the collector which will extend the solar collection periods, both daily and seasonally when compared to the traditional SDHW system, as well as increase the efficiency of the collector. This will help to reduce the reliance on the electric auxiliary heaters and thus decrease the total electricity consumption. Both i-HPASDHW systems considered for this thesis collected more solar energy over the course of the simulated year compared to the base traditional SDHW system. They also consumed less electricity than the two base systems, which directly correlated to lower annual operating costs. It was concluded that the two i-HPASDHW systems analyzed in this study proved to be feasible configurations that performed more efficiently than the two base systems under the simulation conditions. However, it is important to understand that the results presented apply to the specific configurations. While the potential has been shown, prototypes must be built and tested with properly sized equipment for specific applications to get an accurate idea of the potential benefits. Also, equipment costs must be considered to determine payback periods for each system.

University, Diss., 2005--Kassel.

Hybridization and electrification of modern vehicles is today a reality. This effects the construction of the heating and cooling systems in vehicles where earlier the waste heat from the combustion engine was a great heat source. Heat pump systems are commonly used in heating systems in buildings and can therefore also be used for heating the cabin and different components in a vehicle. Modelling a heat pump system and performing simulations gives the advantage of investigating the heating performance of the heat pump during certain conditions. In this master thesis, which is performed in a pre-study project that is performed under the Swedish Electromobility Centre, a heat pump is modelled and the heating performance when changing the vapour quality is investigated during cold environments. Also how the heating capacity for different refrigerants and changing size and speed of compressor is simulated. With the methods and assumptions used, especially isentropic compression, the results shows that decreasing the vapour quality increase the mass flow in the heat pump circuit but the decrease in specific heating is larger which results in an overall decrease in heating capacity. The goal of 10 kW heating capacity can be achieved by increasing the compressor size or make use of waste heat from other vehicle components.

Made available in DSpace on 2014-06-11T19:34:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-19Bitstream added on 2014-06-13T20:05:59Z : No. of bitstreams: 1 azevedo_gjr_dr_guara.pdf: 2654088 bytes, checksum: e45f5184f1ee57d617f3314eb07c30ba (MD5) / O desenvolvimento do projeto e a manufatura das máquinas de pistões axiais de vazão variável são atividades desenvolvidas por poucas empresas no mundo. Uma pesquisa para obter informações sobre o projeto deste tipo de equipamento, revelou pouquíssimas informações técnicas sobre este assunto. Talvez pela falta de uma literatura específica sobre o projeto e o funcionamento deste tipo de equipamento, as empresas brasileiras ainda não conseguiram desenvolver um projeto totalmente nacional. Este tipo de máquina tem grande aplicação na área industrial, móbile e aeronáutica. A importância do desenvolvimento deste trabalho justifica-se pela conquista de uma tecnologia dominada apenas por empresas estrangeiras, causando nas indústrias brasileiras que utilizam esta máquina, uma dependência tecnológica. Sendo assim, este trabalho visa oferecer às empresas brasileiras especializadas em bombas hidráulicas, informações sobre o funcionamento e também uma metodologia detalhada sobre o dimensionamento desta máquina. Calcular e desenhar uma determinada máquina não garante o seu perfeito funcionamento e também não assegura um sucesso sob o ponto de vista mercadológico. Portanto, foi realizado um estudo minucioso, além de uma discussão sobre o assunto com técnicos e engenheiros sobre a melhor forma de usinagem e montagem. Esta etapa precisa ser considerada tão importante quanto necessária. No desenvolvimento deste trabalho há uma apresentação sobre as bombas hidrostáticas disponíveis no mercado. Após a fundamentação teórica sobre o funcionamento da máquina swashplate, descrevendo detalhadamente cada um dos seus componentes, é apresentada uma metodologia para o dimensionamento dos principais parâmetros deste equipamento. Apresenta-se finalmente uma aplicação do método desenvolvido com um exemplo prático, discutindo os resultados alcançados. / Designing and manufacturing of axial piston swashplate machines are activities that few companies have developed around the world. A research in order to obtain information about the design of this kind of machine has revealed only a small amount of technical bulletins. Maybe because of the lacking of a specific literature about designing and how this kind of machine works, brazilian industries have not yet developed a true national design. This machine has many application in the industrial, mobile and aeronautical area. How important this work is justified by the conquering of technology in a world where only foreign industries have it. In this way the present work offers to the brazilian industries that deals with hydraulics, information about how these machines run and a methodology teaching the way how to calculate the machine elements.. Calculating and drawing are not sufficient steps to have a machine running and are not a guarantee of success in the market too. That is why a detailed study, besides a discussing with machine operators and industry engineers was conducted in order to obtain better machining and assembling processes. This step must be considered as important as necessary. Therefore in the way to have this work accomplished, at first, the pumps available in the market are described. The work itself presents the theory related to this kind of machine, a way to explain how it works and describes in detail each part together with a methodology to calculate the machine main parameters. Finally an example of the application of the method is developed.

Class of 2013 Abstract / Specific Aims: To determine whether concurrent use of a proton pump inhibitor (PPI) and a bisphosphonate represent an additional fracture risk compared with bisphosphonate use alone and to identify an increased risk of any particular fracture type. Methods: This study was a systematic review and meta-analysis of data collected from PubMed, Cochrane, OVID Medline, Google Scholar, and IPA. The authors utilized the search terms: bisphosphonate, fractures and proton pump inhibitors. Studies which met criteria of being English-language with adults 18 years of age and older were included. Main Results: The studies were cohort studies and primarily evaluated older adults. The summary effect was that use of a PPI with a bisphosphonate showed a slight increase in fracture risk when compared to bisphosphonate-only therapy (odds ratio [OR] 1.12, 95% confidence interval [CI], 1.06-1.18). Systematic review of similar studies showed varied results, making difficult any conclusion regarding fracture risk among the treatments. Conclusion: In this analysis, PPI + bisphosphonate demonstrated a slight increase in fracture rate without inference to an increase in any particular fracture type compared with bisphosphonate only. However, there is minimal data on the association or causal effect of this increase. The few studies available offered contradictory results. Additionally, database studies are subject to the possibility of residual confounding. Further research using randomized control trial (RCT) design evaluating long term use of bisphosphonates with or without PPI and their impact on fractures is needed to determine if there is an additional degree of fracture risk from the concurrent use.

As a result of the mining that has taken place over the last century in South Africa, many towns and cities have developed around mining hubs, the most significant of these being the city of Johannesburg. Over the years, residential areas have grown around these mine sites, even well after decommissioning of the mining activities. The mining activities left a lasting legacy of derelict mining infrastructure with negative effects on the surrounding environment and community, such as dormant mine shafts, sterilised land and abandoned Tailings Storage Facilities (TSFs). Due to lack of funds, commitment from mine owners and regulators these facilities are often left unrehabilitated, posing negative environmental impacts, including potential health hazards to the surrounding community. This legacy of problems posed by abandoned mines encountered in South Africa is probably unique in scale compared to any country in the world. A significant problem South Africa currently faces is an electricity shortage, especially during the high demand season from the start of June to end of August, when it is winter in South Africa. This period is occasionally associated with so called controlled “load shedding”, i.e. managed power interruptions to prevent overload and subsequent collapse of the electricity supply and distribution network. South Africa is highly reliant on coal-fired power stations for the majority of electricity consumed, which has detrimental effects on the environment due to high carbon emissions. However, a global shift towards renewable energy, as well as South Africa’s energy shortage, has forced the National Energy Regulator of South Africa to encourage greener alternatives. This study is aimed at finding an opportunity to generate more electricity, which is sustainable and with reduced carbon emissions. This study was conducted to determine the financial and practical feasibility of generating energy from the ERGO TSF, near Brakpan Johannesburg, as a post closure land use option. The following options were investigated: • Solar Photovoltaic electricity generation • Pump storage scheme development • A combinations of the above In addition, rainwater harvesting and wind power generation were also considered, but were abandoned early on in the study. From the study it was concluded that a Solar PV plant on top of the ERGO TSF will achieve the highest possible IRR of 10.70% and a power generation capacity of 471.9 MWp. Developing a pump storage scheme at the ERGO TSF can achieve an IRR of 10.27% and generation capacity of 78.2 MW. Combining the two options independently on the same site will result in an IRR of 10.61% and a combined peak generation capacity of 550 MW. If the combined system is required to be independent of the surplus electricity available in the grid an IRR of 10.32% and a combined generation capacity of 550 MW is achievable. From a financial and technical perspective it is considered to be most beneficial to implement only the solar PV plant on top of the ERGO TSF. Construction of a pump storage scheme on TSF is considered to be a challenging undertaking and seeing that its generation capacity is only 17% of that of the solar PV facility on the same ERGO site, it is probably not the optimal solution for utilisation. Solar panels are light weight structures that can easily be installed in large numbers on TSFs with little engineering challenges. / Dissertation (MEng)--University of Pretoria, 2015. / tm2015 / Civil Engineering / MEng / Unrestricted

The content of this master‘s thesis is a study of diaphragm pump with linear drive. Linear motor was used as the linear drive. Thesis is well – founded by theoretic calculation of pump and its design draft. Likewise, the thesis includes optimalization of suction, or pressure, valve for pump, created by using computer fluid dynamics software. Thesis is complemented by basic view of different types of pumps based on the classification by hydrodynamic and hydrostatic pumps. Subsequently, the preview of blood – flow pumps is presented.

This diploma thesis deals with analysis and description of principles of self-priming pumps and description of physical processes, that allow self-priming. With these basements should be proposed innovation of construction for selected type of pump.

No description available.