Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 25, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Richard P. Guyette. Vita. Includes bibliographical references.

Each year, the urbanised population grows exponentially and due to this growth, cities are forced to expand beyond their manageable borders resulting in greater pressure on the surrounding urban environment. Many South African towns or cities are dependent on surface water for water supply. These resources are slowly being depleted and the dependence on groundwater resources is becoming increasingly important. Due to increased mining, industrial and agricultural activities in South Africa the surface water and groundwater environments have become vulnerable to contamination. This study aimed to develop a methodology in which the risks of urbanisation can be quantified. The conceptualisation and qualitative site impact and risk assessments focused on any environmental changes. The urban environment was sub-divided into three distinct areas and analysed separately in order to detect possible groundwater impacts of the water flowing through the urban area. Upstream river flow gauge chemistry by way of tri-linear grouping (piper diagram) of the major anions and cations showed already impacted water due to mining activities north of Potchefstroom. Uranium concentrations in the downstream surface water showed negligible impact as the concentrations remained within the relevant standards over time. Total coliform bacteria concentrations were found to be well above the acceptable levels and these high concentrations are an indicator of water purification inefficiency. Different qualitative risk assessment approaches i.e. the Environmental Risk Assessment method, Fuzzy Logic and the Depth to water, recharge, Aquifer media, Soil media, Topography, Impact of the vadose zone media and Conductivity of the aquifer (DRASTIC) approach risk assessments were compared and used to determine the most effective way to determine the most likely risks associated with urbanisation. Different modelling tools namely, analytical element modelling method (AEM) using the Visual AEM program, a finite difference numerical modelling method using Processing Modflow v.8 (PMWin) were evaluated, however due to insufficient data, an analytical approach had to be developed. This approach incorporated logical steps and associated processes to serve as a guide for future urban hydrogeological investigations. A case study (namely Potchefstroom) was used to test the developed methodology. The developed methodology provides a step by step approach to urban risk assessment, even in areas where there is insufficient data. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015

Each year, the urbanised population grows exponentially and due to this growth, cities are forced to expand beyond their manageable borders resulting in greater pressure on the surrounding urban environment. Many South African towns or cities are dependent on surface water for water supply. These resources are slowly being depleted and the dependence on groundwater resources is becoming increasingly important. Due to increased mining, industrial and agricultural activities in South Africa the surface water and groundwater environments have become vulnerable to contamination. This study aimed to develop a methodology in which the risks of urbanisation can be quantified. The conceptualisation and qualitative site impact and risk assessments focused on any environmental changes. The urban environment was sub-divided into three distinct areas and analysed separately in order to detect possible groundwater impacts of the water flowing through the urban area. Upstream river flow gauge chemistry by way of tri-linear grouping (piper diagram) of the major anions and cations showed already impacted water due to mining activities north of Potchefstroom. Uranium concentrations in the downstream surface water showed negligible impact as the concentrations remained within the relevant standards over time. Total coliform bacteria concentrations were found to be well above the acceptable levels and these high concentrations are an indicator of water purification inefficiency. Different qualitative risk assessment approaches i.e. the Environmental Risk Assessment method, Fuzzy Logic and the Depth to water, recharge, Aquifer media, Soil media, Topography, Impact of the vadose zone media and Conductivity of the aquifer (DRASTIC) approach risk assessments were compared and used to determine the most effective way to determine the most likely risks associated with urbanisation. Different modelling tools namely, analytical element modelling method (AEM) using the Visual AEM program, a finite difference numerical modelling method using Processing Modflow v.8 (PMWin) were evaluated, however due to insufficient data, an analytical approach had to be developed. This approach incorporated logical steps and associated processes to serve as a guide for future urban hydrogeological investigations. A case study (namely Potchefstroom) was used to test the developed methodology. The developed methodology provides a step by step approach to urban risk assessment, even in areas where there is insufficient data. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015

Introduction Neonatal mortality and morbidity from premature birth are still a major concern despite significant advances in perinatal medicine. Objective of the study The primary aim of the study was to establish the feasibility of accurately identifying a cohort of vvomen at increased risk of preterm birth using a modified risk assessment score and fetal fibronectin testing in order to undertake a pilot randomised placebo-controlled trial of nifedipine as a tocolytic. Methodology A population of pregnant women was screened prospectively between 24 and 34 weeks of gestation using a modified risk assessment system. Women identified as high-risk for preterm birth were then tested with fetal fibronectin. Those testing positive were randomised to either nifedipine or placebo. The study at this point was randomised, placebo-controlled and double-blind. Measures of outcome were compared for babies of trial vvomen with high-risk women who withheld consent. Main outcome measures Delivery before 34 weeks, neonatal death, admission to the Special Care Baby Unit (SCBU), chronic lung disease and major cerebral abnormality on ultrasound scan constituted the main measures of outcome. Results Five hundred and thirty four vvomen were identified as high-risk for preterm birth. One hundred and forty two women agreed to participate in the study. Forty nine women delivered before 37 weeks' gestation. The system was sensitive in predicting preterm birth before 34 weeks of gestation and within one week of testing for fetal fibronectin in symptomatic women. Babies of non-consenting mothers fared better overall than babies of the trial women. Conclusion Risk factor scoring and fetal fibronectin testing are useful screening tools that can predict preterm delivery. This sysytem can be clinically useful in the management of preterm labour or women at increased risk for preterm birth. There was no impact on the neonatal mortality or morbidity.

published_or_final_version / Real Estate and Construction / Doctoral / Doctor of Philosophy

The reliability of ocean systems is dependent on organizational factors. It has been shown that low probability / high consequence system failures are overwhelmingly induced by organizational factors. However, no methodology is yet widely accepted for the evaluation of this phenomenon or its accurate quantification. A qualitative complementary approach is proposed based on the CANL (Complex Adaptive Non-Linear) model. In the first part, the understanding of organizational processes that affect reliability is sought. The approach is applied to several case studies based on published information: the "Story of a Platform Audit" (where no failure occurred) and some offshore accidents. A methodology is proposed to complement regular safety audit procedures. The approach is shown useful also to improve post-mortem investigations. In the second part, quantitative probabilistic formulations are revised, based on the understanding obtained through the previous approach. Some of the limitations of these quantitative methods are pointed out. The Reliability State of an Organization is defined and a ranking for its evaluation is proposed. Preliminary guidelines are presented for the use of this approach as a framework to identify suitable quantitative methods for a given case. The use of a qualitative approach is demonstrated. A different insight into organizational factors is achieved based on a disciplined approach that relies on experience. Significant conclusions regarding quantitative methods, their limitations and appropriate use, are obtained. / Graduation date: 1999

Introduction: Acute gastroenteritis is a common illness in humans. It has a high morbidity worldwide and in the United States (U.S); a sizeable mortality is reported in developing countries. Viruses are a common cause of acute gastroenteritis and noroviruses are the leading cause of non-bacterial gastroenteritis (1). Fomites play an important role in the infection cycle of norovirus. This study explored the comparability between a quantitative microbial risk assessment (QMRA) model to predict the probability of illness from norovirus due to environmental contamination with actual observed attack rates, the impact of appropriate cleaning procedures on fomites contamination, and the role of fomites in the transmission of norovirusMethod: Data from three different norovirus illness outbreaks occurring from 2004 to 2005 in Arizona in different venues were used. Questionnaires were used to determine demographics, symptoms associated with gastrointestinal illness, medical visits, and potential exposures such as food items consumed. When available, stool samples were collected from ill participants. Fomites samples were also gathered from the different venues; houseboats, college summer camp living spaces, and a restaurant. These samples were tested for norovirus using reverse transcriptase polymerase chain reaction (RT-PCR). Viral concentration on fomites was calculated using the most probable number methodology.Results: Norovirus was found on fomites from all three outbreaks. Improper cleaning of fomites increased the proportion of norovirus positive fomites from 40 percent to 70 percent in contrast, after cleaning and disinfection with 5000 mg/L free chloride, the proportion of norovirus positive fomites decreased to 33%. The predicted values from the quantitative microbial risk assessment model were consistent with the observed epidemiological attack rates.Conclusion: This study showed unequivocally that fomites play an important role in the transmission cycle of norovirus, and that improper cleaning and disinfection procedures only serve to spread the virus to previously uncontaminated fomites. In the case of outbreaks where people are not always available to answer questionnaires, QMRA should be considered as a worthwhile alternative to a full-scale epidemiological study.

No description available.

<p>Assessing and understanding the health needs and abilities of university and college students is vital in creating healthy campus communities. Student learning is a central part of the higher education academic mission, and health promotion serves this mission by supporting students and creating healthy learning environments. Findings from various studies suggest that students entering the university setting put themselves at risk through unhealthy behaviours. Health science students are the future health professionals who will teach health promotion and disease prevention. The aim of this study was to determine and analyse health risk behaviours and health promoting behaviours among health science students at the University of the Western Cape. The study further aimed to identify the factors influencing these students' engagement in these risk behaviours.</p>

Throughout North America populations of white sturgeon (Acipenser transmontanus) are threatened, in part due to poor annual recruitment. Definitive causes for this are not yet known, but the effects of contaminants are suspected to contribute. White sturgeon are exposed to a range of contaminants as they tend to inhabit industrialized river systems such as the Columbia and Fraser. White sturgeon are not commonly studied in ecotoxicology and their vulnerability as a species to contaminants of environmental concern is not well defined. To date, few exposure studies have been conducted with larvae, fry, and/or juveniles of this species; life stages often considered most susceptible to pollutants. Specifically, little work has been conducted to characterize effects of metals on white sturgeon. In the Upper Columbia River (UCR) a population of white sturgeon has been experiencing poor annual recruitment for over thirty years, and the effects of metal pollution have been hypothesized as a potential contributing factor. In particular, Teck Metals Ltd. (Teck) operates a metallurgical facility in Trail, BC, Canada that currently discharges processed effluent into the river and historically released other metal containing tailings such as slag. There are concerns that concentrations of trace-elements, such as copper, lead, cadmium, and zinc, associated with the effluent and/or slag, might have detrimental impacts on the surrounding ecosystem, including the local white sturgeon population. In 2006, a remedial investigation and feasibility study (RI/FS) was initiated in the UCR, under the oversight of the US EPA, and this project is contributing to the portion dedicated to the risk assessment of the exposure of white sturgeon to metals. The goals of this project were to develop information on toxicity of water, sediments and associated slag to help characterize sensitivity of white sturgeon to metals, and assess associated risks of metals on the population of white sturgeon in the UCR. Previous work conducted as part of a MSc degree, examined the effects of liquid effluent released by Teck on early life stages of white sturgeon. In addition, baseline information of toxicity due to sub-chronic exposure of early life stage sturgeon to copper, cadmium, and zinc, were developed. The thesis presented herein builds upon this previous work and has three major components to further characterize sensitivity of white sturgeon to metals and risk of exposure in the UCR. Specifically, a series of acute dose-response experiments were conducted with various early life stages of white sturgeon and resulting threshold values compared to water quality standards to assess protectiveness. Sensitivity of white sturgeon to metals was characterized by conducting parallel experiments with standard test species, such as rainbow trout (Oncorhynchus mykiss) and fathead minnow (Pimephales promelas), as well as parallel field exposures in UCR water to develop water effect ratios (WERs) and assess relative bioavailability. A second set of experiments investigated whether exposure to water downstream of the metal smelter in Trail, BC affected survival or growth of white sturgeon. Mobile laboratories were situated riverside upstream and downstream of the smelter and the effects of potential contaminants within UCR water to early life stage white sturgeon were investigated under chronic exposure conditions. The third set of experiments involved characterizing UCR sediment toxicity and potential effects to sturgeon. Results from this research indicate that early life stage white sturgeon are relatively sensitive to copper, cadmium, lead, and zinc in comparison to other fishes. Sturgeon were particularly sensitive to copper, especially during early life stage development when larvae are transitioning to exogenous food. Thresholds for effects of copper on early life stage white sturgeon (LC50’s ranged between 9 and 22 μg/L) bracket water quality criteria for the protection of aquatic life (7.9 μg/L ± 1.5). This result indicated that white sturgeon in the UCR might not be adequately protected. Environmentally relevant concentrations of metals, such as copper, found in water, sediment, or waters associated with sediment of the UCR, including pore water and overlying water, may approach or exceed water quality criteria and lethal concentration (LC) values for sturgeon. Results from the risk assessment portion of this project, however, indicated that contaminants in the water column downstream of the metal smelter at Trail did not likely affect survival of white sturgeon. Dilution of Teck effluent in the river is such that, at the major spawning site where early life stages of sturgeon are likely to be present and where the riverside experiments from the present project were conducted, there would be no toxicity expected. Contaminants associated with sediments in the UCR and their impact on survival of sturgeon is also of concern as early life stages inhabit benthic habitats, on surface sediments, or in interstitial space between stones. Analytical results from this project did indicate that UCR sediment downstream of the smelter facility were significantly greater (p < 0.01) in concentrations of trace-elements, such as copper, lead, cadmium, and zinc, relative to reference sites. However, survival of white sturgeon was not adversely affected following exposure to UCR sediments. This project provided valuable information to help assess potential causes for poor recruitment of white sturgeon in the Columbia River. Advancements were made in characterizing the effects of metals to white sturgeon. In particular, life stage-specific sensitivities were identified that could have a significant impact on current risk assessment approaches and the derivation of protective water quality standards. There are several hypotheses as to why the number of white sturgeon have been decreasing in the UCR over the last few decades, but as of yet, no definitive cause for poor recruitment has been identified. As more research is conducted, possible causes for recruitment failure can be eliminated. Based on results from this project, metals in the UCR do not appear to be contributing directly to decreased survival of early life stage sturgeon.