Thesis (M.S.)--Ohio University, November, 2007. / Title from PDF t.p. Includes bibliographical references.

No description available.

Thesis (M.C.E.)--University of Delaware, 2009. / Principal faculty advisor: Chin-Pao Huang, Dept. of Civil & Environmental Engineering. Includes bibliographical references.

Campylobacter spp. have been isolated from live poultry, production environment, processing facility, and raw poultry products. The detection of Campylobacter using both quantitative and qualitative techniques would provide a more accurate assessment of pre- or post harvest contamination. Environmental sampling in a poultry grow-out house, combined with carcass rinse sampling from the same flock may provide a relative assessment of Campylobacter contamination and transmission. Air samples, fecal/litter samples, and feed pan/drink line samples were collected from four commercial chicken grow-out houses. Birds from the sampled house were the first flock slaughtered the following day, and were sampled by post-chill carcass rinses. Quantitative (direct plating) and qualitative (direct plating after enrichment step) detection methods were used to determine Campylobacter contamination in each environmental sample and carcass rinse. Campylobacter, from post-enrichment samples, was detected from 27% (32/120) of house environmental samples and 37.5% (45/120) of carcass rinse samples. All sample types from each house included at least one positive sample except the house 2 air samples. Samples from house 1 and associated carcass rinses accounted for the highest total of Campylobacter positives (29/60). The fewest number of Campylobacter positives, based on both house environmental (4/30) and carcass rinse samples (8/30) were detected from flock B. Environmental sampling techniques provide a non-invasive and efficient way to test for foodborne pathogens. Correlating qualitative or quantitative Campylobacter levels from house and plant samples may enable the scheduled processing of flocks with lower pathogen incidence or concentrations, as a way to reduce post-slaughter pathogen transmission. / Master of Science in Life Sciences

Graduation date: 2000

Thesis (MTech. degree in Chemistry)--Tshwane University of Technology, 2010. / Discusses an accurate and sensitive method for the determination of trace levels of mercury in environmental air samples may be established using cost effective technologies.

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 273-303). Also available in electronic version. Access restricted to campus users.

Thesis (M.Eng.)--Memorial University of Newfoundland, 2003. / The CD-ROM contains Appendix D: mass spectrometer data. Bibliography: leaves 94-97.

Ph.D. / A lot of chemicals are used in agriculture to increase production per cost. Unfortunately most of these chemicals find their way into the final agricultural product or get washed off into other systems where they may pose health and environmental concerns. As such monitoring of these compounds where they are not needed is necessary to avoid unwarranted pollution and the effects associated with them. This requires the use of analytical techniques and instrumentation. Analytical chemistry, especially in the area of sample preparation and clean-up, has shifted focus mainly on greener methods that produce only minute quantities of waste without sacrificing efficiency. This has led to the conception of a term QuEChERS (acronym for Quick, Easy, Cheap, Effective, Robust and Safe) to reflect this trend in sample preparation. Efforts have been made in this regard to reduce the amount of chemicals used; as a result miniaturised techniques have evolved. One such technique that is easiest and cheapest is solvent micro-extraction especially the single-drop format, wherein only a few micro-litres of an organic solvent are used to sample the aqueous solution with the same volume being transferred into the instrument for analysis. This study reports the advances made in development of a modified single-drop micro-extraction (SDME) technique through the deliberate introduction of an air-bubble to facilitate mass transfer. This is termed bubble-in-drop single-drop micro-extraction (BID-SDME). The method has been reported for the first time in our earlier work. This study started off with the validation of the method using triazine mixture (TP 619) as model herbicides. The method was validated for linearity (0.05 – 5 ng/mL), reproducibility and repeatability (%RSD < 10%), matrix effect, limits of detection (pg/mL range) and quantification as well as accuracy.

Rabies has been reported in Tanzania, mainly in the southern highland regions, since 1954. To date, rabies is endemic in all districts in Tanzania and efforts are being made to contain the disease. It was determined that mass vaccination of at least 70% of an animal population is most effective, in terms of profitability and cost, in reducing transmission of rabies. The current approach for vaccination in Tanzanian villages takes some features from the EPI method but is rather basic and unreliable. This mini-dissertation proposes using a sampling technique which incorporates the spatial component of the village data and minimises the walking distance between the sampled houses while ensuring the 70% coverage of the animal population. / Mini Dissertation(MSc)--University of Pretoria, 2017. / STATOMET The Centre for Artificial Intelligence Research (CAIR) National Research Foundation of South Africa (NRF CSUR grant number 90315) / Statistics / MSc / Unrestricted