A prospective study was conducted on a group of 160 students from 9 to 14 years of age with learning disabilities to predict neuropsychological outcome using perinatal information as predictors. Perinatal information was obtained from the Maternal Perinatal Scale (MPS) (Dean & Gray, 1985). Subjects' neuropsychological functioning was assessed by the Short Neuropsychological Screening Device (SNSD) (Reitan & Herring, 1985). Information concerning subjects' intelligence was obtained from the Wechsler Intelligence Scale for Children-III (WISC-III) administered within the past two years. Hollingshead's Four Factor Index of Social Status was employed to determine subjects' socioeconomic status. A stepwise multiple regression analysis yielded a regression model that contained a subset of 7 perinatal risk factors, involving: (1) Obstetric History; (2) Gestational Age; (3) Psychosocial Events; (4) Delivery; (5) Intrauterine Stress; (6) Teratogenic Stress; and (7) Fetal Oxygenation. A hierarchical regression analysis was further performed to examine if adding socioeconomic and intellectual information to the regression model could increase the prediction of neuropsychological outcome. Results showed that up to 82% of the variability in the neuropsychological outcome was explained by the linear composite of the 7 risk factors. When socioeconomic and intellectual information were added to the regression model, the prediction of neuropsychological outcome was significantly improved. About 201 of the students with learning disabilities in the present study were found to display symptoms similar to minimal brain damage (MBD) relating to poor visual-motor integration, underdeveloped language skills, and aphasic conditions. The results support the theory of a "continuum of reproductive casualty" proposed by Pasamanick et al. (1956). The importance of detecting early indicators of neuropsychological deficits in at risk children was further suggested by the present study. / Department of Educational Psychology

Quantitative soil ingestion studies employing a mass balance tracer approach have been used to determine soil ingestion rate for use in human health risk assessments (HHRAs). Past studies have focused on soil ingestion in populations living in urban/suburban environments and the results have been highly variable. Moreover, there is a paucity of reliable quantitative soil ingestion data to support human health risk assessments of other lifestyles that may be predisposed to ingesting soil, such as indigenous populations following traditional lifestyles. Thus, the primary objective of the research was to determine if populations following lifestyles typical of traditional land use practices in rural or wilderness areas ingest more soil than populations living in urban or suburban environments. Further, the research investigated the use of alternative mass balance tracers, specifically isotopes of the 238U and 232Th decay series, to reduce soil ingestion estimate variability. Mass balance tracer methods were developed and validated in a pilot canine study, and methods using isotope tracers were adapted to permit quantification of sediment ingestion in the benthic fish Moxostoma macrolepidotum (Shorthead Redhorse Sucker). A pilot human soil ingestion study of 7 subjects from an Aboriginal community in British Columbia was conducted over a 3-week period. The mean soil ingestion rate calculated using the daily means of the 4 elemental tracers with the lowest food-to-soil ratios (i.e., Al, Ce, La, Si) was observed to be approximately 74 mg d-1 (standard deviation 91 mg d-1), The median soil ingestion rate was 60 mg d-1, and the 90th percentile was 196 mg d-1. These soil ingestion rate estimates are higher than those currently recommended for HHRAs of adults, and higher than those obtained in most previous studies of adults. However, the estimates are much lower than the earlier qualitative assessments for subsistence lifestyles (i.e., 330-400 mg d-1). The study results also demonstrated that isotopes of the 238U and 232Th decay series radionuclide are not reliable mass balance tracers for estimating soil ingestion in humans; however, they may be useful for quantifying soil and sediment ingestion in wildlife.

This study sought to characterize the risk to human health from dietary mercury (Hg) exposure in two Inuit communities, Repulse Bay and lgloolik. Hg exposure was estimated using food frequency questionnaires. Body burden was determined by measuring Hg in hair samples. Estimated average daily Hg exposures for women of child-bearing age were 21.3 mug in Repulse Bay, and 6.0 mug in lgloolik; the general population exposures were 43.1 mug in Repulse Bay and 23.2 mug in lgloolik. Average hair concentrations were 2.1 mg/kg and 2.8 mg/kg in Repulse Bay, 2.1 mg/kg and 6.2 mg/kg in lgloolik for women of child-bearing age and the general population respectively. No participants had concentrations above the "at risk" concentration of 30 mg/kg. Significant correlations were observed between hair Hg concentration and traditional food intake. These results do not necessitate direct intervention, but validate continued monitoring of Hg exposure in Nunavut.

Thesis (M.A.)--Carleton University, 2003. / Includes bibliographical references (p. 141-151). Also available in electronic format on the Internet.

Thesis (Ph.D.) - Simon Fraser University, 2004. / Theses (Dept. of Biological Sciences) / Simon Fraser University.

Thesis (Ed.D.)--Teachers College, Columbia University, 1994. / Includes tables and appendices. Typescript; issued also on microfilm. Sponsor: Nancy Lovejoy. Dissertation Committee: Marvin Sontag. Includes bibliographical references (leaves 58-71).

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 212-224). Also available in electronic version. Access restricted to campus users.

Thesis (M.S.)--University of Michigan, 1991.

Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 276-302). Also available on the World Wide Web.

Thesis (PhD.(Medical Virology)--Faculty of Health Sciences)-University of Pretoria, 2004. / Summary in English and Afrikaans. Includes bibliographical references.