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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

Variations in pollen and fungal spore air spora: an analysis of 30 years of monitoring for the clinical assessment of patients in the Western Cape

Berman, Dilys Melanie 19 February 2019 (has links)
Background and aims: Pollen and fungal spore concentrations in the atmosphere of Cape Town have been monitored since 1984 in two areas of Cape Town. Volumetric spore traps were used to monitor the air spora that trigger allergic disease in susceptible individuals. A pollen count was produced for the diagnosis and treatment of patients attending respiratory clinics at the academic hospitals but the findings of the different aerobiological monitoring areas have never been compared. We considered that more than one aerobiological area should be monitored to produce a representative pollen count for the most densely populated areas of Cape Town. Methods: The pollen taxa and fungal spore genera collected from the two aerobiological zones, now named the West Coast and Valkenberg Aerobiomes were defined. Eight of the air spora were selected for detailed comparison. The relative abundance and seasons of Poaceae, or grasses, the tree pollen taxa Cupressaceae, Platanus and Quercus and the fungal spores: Alternaria, Cladosporium, Epicoccum and Pleospora were evaluated and compared in each aerobiome. Differences in the annual distribution and seasonal limits of the air spora in the two aerobiomes were found using statistical techniques. Results: Significant differences were found between the tree pollen loads in the different aerobiomes. Spring pollinating trees were the most prevalent pollen taxa in the Valkenberg Aerobiome with short flowering seasons that spanned six weeks (August-September) for Platanus and Quercus but eight weeks (July-September) for Cupressaceae. The grass season was longer (September- March) in both aerobiomes and grasses flowered earlier at the inland site. Poaceae dominated the annual pollen catch at the coastal aerobiological zone. Parietaria was the only weed taxon with significant concentrations. Pleospora showed a seasonal trend peaking in mid to late winter at the West Coast. No comparable peaks for Pleospora were seen from the Valkenberg sites. Cladosporium concentrations were low and seldom breached the significant threshold of 3,000 spores/m-3 in either of the aerobiomes. The influence of meteorological parameters on Cladosporium and temperature on Poaceae was explored. A table was designed that clarified the ranges for Cladosporium and a formula was adapted for predicting the start of the grass season. Significant decreases in the Poaceae concentrations in both aerobiomes were observed and discussed with reference to Global Warming. Conclusions: The differences in the pollen spectra and seasonality of the selected allergenic air spora indicate that both aerobiomes should be monitored concurrently for patients who live and work in these different microclimates. Pollen profiles for skin, blood and specific IgE testing panels should be reassessed to include Cupressaceae, Parietaria, Myrica, Pleospora and basidiospores. When patients are recruited for clinical drug trials, their place of residence or work should be within the realm of the aerobiome that is being monitored. Current pollen monitoring programmes should be consulted for immunisation regimes to grass and tree pollen. These findings will be applied to the diagnosis and prescription of immunotherapy in clinical practice.
182

Local development and calibration of a passive sampler for monitoring of particulate matter

Mukota, Tinashe 10 1900 (has links)
The measurement of ambient particulate concentration (PM10 and PM2.5) using active monitors requires expensive or labour-intensive apparatus or both. Although PM is a priority pollutant, this has precluded widespread or intensive ambient particulate monitoring networks to be set up in South Africa, except in some priority areas. In this study, locally manufactured passive PM monitoring devices (samplers), based on a design initially published by researchers at the University of North Carolina (UNC), were calibrated for the measurement of PM10-2.5. Duplicate samplers of each type (local and UNC) were co-located at eight reference stations equipped with TEOM (Tapered element oscillating microbalance) or BAM (Beta radiation attenuation monitor) particulate monitors in three networks. Imaging of the substrate was carried out using an optical microscope to limit the cost of analysis. The images (10 to 49 per sample) were analysed using both proprietary (Zeiss AxioVision®) and open-source (ImageJ) software at 100X and 200X magnification. Considerable variation exists between the four co-located local and UNC samplers at all stations, although the latter show lesser discrepancies when analysed using the AxioVision software. Greater agreement of the local samplers and the continuous monitors is noted at a 200X and 100X magnification using the AxioVision software with R2 = 0.81 and R2 = 0.79 respectively. The precision of PM10-2.5 measured with the passive samplers was highly variable with calculated CVs ranging from 10.4% to 73.3%. 82% of the CVs were less than 40%. The average CV for all samplers was 34.6%. Passive samplers analysed using the AxioVision software recorded smaller average discrepancies of 45.3% at 100X and 37.3% at 200X magnification. Samplers analysed using ImageJ at 100X magnification exhibited the highest percentage difference from the reference values (81.2%). Using a two factor ANOVA we can show that (at 95% confidence) the analysis software and the imaging magnification have the most significant effect on the calculated sampler concentration results. A disadvantage of passive samplers is large number of days (2-7) required to produce statistically significant values hence disqualifying it for use as a reference method. The device is, therefore, more suitable for screening-level, high spatial density sampling, but some non-regulatory applications are pointed out. / Dissertation (MEng)--University of Pretoria, 2019. / Chemical Engineering / MEng (Environmental Engineering) / Unrestricted
183

Instrumentation for Multi-Electrode Voltammetry

Ho, I-Pin 01 January 1990 (has links)
When metal pollutants exist in natural water, their toxicity is dramatically dependent on the chemical species. Numerous sophisticated techniques and instruments have been developed to detect metal pollutants at very low concentration levels. However, one important factor is often ignored, i.e., rarely is species determination required. Electrochemical (EC) methods have the particular advantage of being, in principle, a species-sensitive method rather than an element-sensitive method for the study of metal speciation in natural waters. The goal of this research was to develop an instrument using the EC technique for speciation and general voltammetric studies. It was accomplished by designing a flow-through EC cell containing multi-electrodes to which various fixed potentials over a selected range were applied. A special potentiostat was designed to supply a selected potential to each electrode in the cell. Potential control was provided by placing a combined counter-reference electrode at circuit ground and connecting each working electrode to the inverting input of a current follower which had a potential applied to its non-inverting input from two digital-to-analog converters and a resistor network. Integrating current followers were used for measuring signal currents generated by the electrolytes samples on each electrode. A multiplexing circuit, including an analog-to-digital converter, was used to fulfill data acquisition. These circuits were interfaced to a computer and the readout was a pseudo-voltammogram which is a plot of amperometric currents versus various applied fixed potentials on each electrode. Details of the instrumentation, software, and some initial results are described.
184

Tracing Atlantic Sea Scallops Using Radio Frequency Identification (RFID) Technology

Shoup, Will 01 January 2023 (has links) (PDF)
Traceable seafood can be linked back to its origin and method of catch. Improving the traceability of marine organisms involves establishing a transparent Chain of Custody (CoC) by collecting data at checkpoints throughout the supply chain, from ship to shore to store. This report explores the feasibility of integrating Radio Frequency Identification (RFID) technology into the United States Atlantic sea scallop (Placopecten magellanicus) fishery in order to improve traceability. This report serves as a forward-looking evaluation of RFID technology that is intended to inform interested stakeholders of its functionality and capabilities. It is not intended to serve as a management proposal.
185

Can In-vivo Self-Monitoring Improve Discrete Trial Instruction Implementation?

Lai, Rachel Nicole 07 1900 (has links)
Beneficial consumer outcomes are most likely when behavior-analytic interventions are implemented with high procedural fidelity (i.e., degree to which the procedure is implemented as intended). Video self-monitoring, which involves teaching staff members to monitor their own procedural fidelity when watching recordings of themselves, can be used to improve and maintain high procedural fidelity, but video self-monitoring requires additional staff time and resources. In-vivo self-monitoring, which involves monitoring procedural fidelity during or immediately following implementing a behavior-analytic intervention, could be a cost-effective option. However, in-vivo self-monitoring needs additional research to understand its effects on procedural fidelity. This current study analyzed the effects of in-vivo self-monitoring on the procedural fidelity of three behavior technicians implementing discrete trial instruction with children with autism. We used a nonconcurrent multiple baseline across participants design to teach participants how to score their procedural fidelity during their discrete trial instruction session. Data suggested that in-vivo self-monitoring was effective for two out of three participants, and those two participants were more likely to be accurate in their self-scored procedural fidelity. Procedural fidelity for the third participant did not increase with in-vivo or video self-monitoring, and the third participant was less likely to be accurate in their self-scored procedural fidelity. During baseline and intervention, two out of three participants were more likely to error on the consequence portion of discrete trial instruction. Results of this evaluation were used to inform the supervisors about the efficacy of self-monitoring for each staff member, and implications of using self-monitoring in practice is discussed.
186

Preliminary investigations into pharmacodynamic monitoring of cyclosporine in cats

Cridge, Harry 01 May 2020 (has links)
Existing pharmacokinetic monitoring tools for cyclosporine fail to correlate with clinical response. In dogs, pharmacodynamic monitoring of nuclear factor of activated T cell (NFAT) regulated cytokines is thought to provide a better overall evaluation of the immune response to cyclosporine than blood levels; however, such monitoring tools are not available in cats. In this study, we designed and optimized a protocol for maximal T lymphocyte stimulation in cats. This is the first step in the development of a pharmacodynamic monitoring tool for cyclosporine in cats based on expression of NFAT-regulated cytokines. We also confirmed that cyclosporine has anti-lymphocytic properties in cats, and we were the first to document induction of apoptosis by cyclosporine in cats. Differences in individual patient response to cyclosporine may be influenced by apoptotic response of lymphocytes to cyclosporine. Additional studies are required to optimize and validate polymerase chain reaction monitoring of NFAT-regulated cytokines for cyclosporine-mediated immunosuppression.
187

Student progress monitoring: teachers' perceptions

Barron, Darlene H 08 August 2009 (has links)
The Mississippi Student Progress Monitoring System (MSPMS) was developed for the Mississippi Department of Education to be used to monitor student progress on the state framework which constitutes the curriculum for each course taught in Mississippi schools. This study was designed to investigate teachers’ perceptions of the implementation and use of the MSPMS. Research question 1 was to determine if the various independent variables of age, level of education, years of experience as an educator, level of school where teaching, perceived level of computer and/or technology comfort, perceived level of computer and/or technology experience, subject area taught, number of MSPMS tests created, number of MSPMS tests given, amount of support provided, whether program works, and importance of information gained from MSPMS made any difference in teachers’ perceptions of the implementation and use of the MSPMS; and research question 2 was to determine whether the teachers’ perceptions and the various independent variables had any significant relationships. Research question 3 looked at teachers’ attitudes toward MSPMS. There were no statistically significant differences among the dependent and independent variables. Findings for research question 2 showed that there were no statistically significant correlations among the dependent and independent variables. However, correlations among the independent variables revealed statistically significant relationships between age and years of experience, subjects taught and school level taught, technology experience and level of education, and subjects taught and number of tests given. Examination of the response frequencies for situations in the vignettes for research question 3 revealed that teachers reported feeling more frustrated than anything else when confronted with adversities with the technologies or the MSPMS. All of the findings in this study are limited to a rural Mississippi school district using MSPMS.
188

A Turnkey Solution for a Web-Based Long-Term Health Bridge Monitor Utilizing Low Speed Strain Measurements and Predictive Models

KIMMEL, GREGORY 28 August 2008 (has links)
No description available.
189

Transmission Scheduling Using Adaptive Neuro-Fuzzy Inference System For Minimizing Interference in Wireless Body Area Networks (WBANs)

Chintapalli, Sahithi January 2015 (has links)
No description available.
190

Development of a Wireless Borehole Extensometer for Monitoring Convergence in Underground Mines

Thomas, William Robert 21 May 2015 (has links)
An extensometer has been developed to continuously monitor roof extension in underground mines. The extensometer is designed to be installed in the MSHA-mandated test holes in the roof and measures the displacement between an anchorage point at the top of the borehole and the hole in the roof of the excavation. Once installed, the extensometer will report displacement through semi-wireless communications network. The extensometer is hard-wired into the permissible MIDAS datalogger, where results can be obtained wirelessly via the MIDAS user interface. Lab tests have indicated that the device produces displacement data. The device was installed in one underground coal mine to review its effectiveness in the field. / Master of Science

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