Three experiments were conducted to study the influence of dietary fatty acids on the production performance and immune response of chickens. In experiment I, forty day-old broiler chicks were fed diets containing 5% of either animal fat + conjugated linoleic acid (CLA) (Diet I), sunflower oil (Diet II), flax oil (Diet III) or fish oil (Diet IV). No significant differences (P>0.05) were observed between the live weight of birds. The liver tissue total fat content was lower (P<0.05) in treatment I and II. The fatty acid composition of breast and thigh muscle, liver, heart, pericardial fat, plasma, splenocytes and gut associated lymphoid tissue differed (P<0.05) between treatments. The thiobarbituric acid reactive substances (TBARS) of breast and thigh muscle, liver and heart tissue were lower (P<0.05) in Diet I fed birds. Serum antibody activity was decreased (P<0.05) in Diet II fed birds. In experiment II, 120 day-old broiler chicks were fed diets containing 3.5% of either animal fat + conjugated linoleic acid (CLA) (Diet I), sunflower oil (Diet II), linseed oil (Diet III) or fish oil (Diet IV). Body weight gain was higher (P<0.05) in Diets III and IV compared to Diets I and II fed birds. Feed intake was increased (P<0.05) in Diet IV fed birds. Birds fed Diets III and IV had higher (P<0.05) n-3 fatty acids in all tissues studied. A preferential incorporation of CLA was observed in spleen mononuclear cells. TBARS were higher (P<0.05) in the breast and thigh muscle of Diet IV fed birds. Serum anti-BSA antibody content was higher (P<0.05) in birds fed Diets III and IV. Delayed type hypersensitivity (DTH) response was increased (P<0.05) in Diets IV and III fed birds. Lymphocyte and spleen mononuclear cell CD4⁺, CD8⁺ and IgM⁺ cell population did not differ (P>0.05) among treatments. In experiment III, 120 layer birds were fed diets containing 3% of CLA+animal fat (Diet I), sunflower oil (Diet II), canola+flax oil (Diet III) or fish oil (Diet IV). Egg production, feed consumption and feed efficiency did not differ (P>0.05) among treatments. Birds fed Diets III and IV had higher content of n-3 fatty acids in eggs. Eggs from hens fed Diet I incorporated higher (P<0.05) CLA and saturated fatty acids with a concomitant reduction in (P<0.05) monounsaturated fatty acid content. A preferential incorporation of CLA was observed in eggs over other tissues. TBARS were higher (P<0.05) in breast and thigh muscle of Diet IV fed birds. Egg TBARS content did not differ (P>0.05) among treatments. Serum and yolk anti-BSA antibody contents were higher (P<0.05) in birds fed Diets III and IV. DTH response was increased (P<0.05) in Diets IV and III fed birds. Lymphocyte and spleen mononuclear cell CD4⁺, CD8⁺ and IgM⁺ cell population did not differ (P>0.05) among treatments. Feeding n-3 fatty acids increased antibody mediated immune response while n-6 fatty acids and CLA increased cell mediated immune response. / Graduation date: 2003

Elemental sulphur (S0) is produced from processing bitumen from the oil sands region, Alberta. Long term storage of this S0 is under consideration. The objective of the current study was to determine the controls on water migration in variably saturated S0 blocks. Based on visual observations of S0 blocks, they were characterized as a hydrophobic fractured porous media. Thus, measurements of the hydraulic characteristics, including porosity (n) and hydraulic conductivity (K) of the matrix and the fractured media, were undertaken. These data were used to create characteristic relationships of unsaturated K (Kunsat) and volumetric moisture content (è) change with change in positive injection pressure (Ø).<p>Analyses showed that the mean total matrix n (nm) was 0.094 ± 0.035 (n = 280), the mean n available for water migration (na) was 0.065 ± 0.044 (n = 8) and the mean (geometric) K for the matrix was 2.0 x 10-6 ± 2.1 x 10-6 ms-1. In the case of vertical fractures, the aperture frequencies were measured to be 2.5, 10.0 and 21.0 m-1 for fractures with apertures > 1.4, 1.4 to 0.6 and < 0.6 mm respectively while the frequency of horizontal fractures, were measured to be 1.7 and 3.7 m-1 for with apertures > 1.4, and < 1.4 mm respectively. The fracture n (nf) was determined to be 0.0135. è Ø relationships were determined for both the fractured and non fractured media. From these plots, water entry values of 9 mm and 1 m were determined for the fracture pore space and the matrix pore space, respectively.<p>Simulations of packer tests resulted in a bulk saturated K (Kb) values ranging from 8.5 x 10-5 to 2 x 10-4 ms-1 above 9 m depth and 3 x 10-6 to 1.5 x 10-5 ms-1 below 9 m depth. Coupled Kunsat Ø and è Ø relationships were used to conceptually describe water migration in S0 blocks under different precipitation and mounding conditions. These plots also showed that the Kb is dominated by the fractures.

ABSTRACT Background: Polyunsaturated fatty acids (PUFA) are found in nuts and seeds, salad dressings and vegetable oil and are prone to oxidation during storage and food preparation. Evidence supports that consumption of oxidized lipids promotes atherosclerosis and glucose intolerance in animal models. However there is a dearth of evidence with regard to the amount of oxidized lipids consumed and its association with parameters of adiposity and glucose homeostasis in humans. Objective: The objective of this study is to estimate the amount of oxidized lipids in common foods and the oxidized lipid consumption in the US population using the data from National Health and Nutrition Examination Survey (NHANES) 2005-06. The second objective of this study is to investigate if there is an association between consumption of oxidized lipids with markers of adiposity and glucose tolerance. Methods- Foods with possible high oxidized lipid content were selected from the NHANES food frequency questionnaire. Oxidized lipid content /Peroxide Values (PV) of these foods were determined from published values in the literature. Oxidized lipid consumption was stratified into tertiles to determine the relationship between consumption of oxidized lipids and markers of adiposity. Regression analysis was used to explore to the extent to which body fat % and HOMA- IR scores could be attributed to oxidized lipid intake. Results- The estimated mean daily consumption of oxidized lipids was 0.625 meq/kg of fat for the US population. Estimated mean consumption of oxidized lipids was significantly greater in men compared to women, in children compared to adults and among African Americans compared to other races. In both men and women it was observed that the markers of adiposity like body fat%, waist circumference, triceps skinfold decreased significantly with increased consumption of oxidized lipids. However in women (below 18 years) there was a significant increase in HOMA-IR with increased consumption of oxidized lipids. Conclusion- Increased consumption of oxidized lipids is associated with decreased fat mass but increased glucose intolerance in women, but not in men.

Chloride concentrations at the Greenbrook well field in Kitchener, Ontario, have been steadily increasing over the past several decades and may soon pose a threat to drinking water quality. Drinking water limits at some wells have already been exceeded. The Regional Municipality of Waterloo (RMOW) relies mainly on local groundwater resources for its drinking water supply, and the Greenbrook well field is the oldest of 50 municipal well fields contributing to this supply. Urban growth and the expansion of city limits over the years has surrounded the well field, placing it in a high risk area in need of protection. As such, protection of this water supply is essential until alternative sources can be found. Road salt has been identified as the prime source of the chloride contamination, and various management alternatives and remediation strategies are currently being studied. In order to characterize the behaviour of chloride in the subsurface, an understanding of the mechanisms that control travel of chloride to the water table and through the groundwater system is needed. For the first phase of this work, a 2-D variably-saturated flow and transport model (SWMS-2D) was used to evaluate the effect of seasonal fluctuation in chloride loading to a generic aquifer system. Chloride was applied over the surface of the model in seasonal pulses that correlated with temperature and precipitation. The model showed a dampening of the seasonal response with depth that lead to the conclusion that long-term transport models can neglect seasonal changes in solute loading. For the second phase of this work, a proven 3D finite element transport model (Waterloo Transport Code: WTC) was used to simulate road salt impacts to the well field. Road salt was applied over selected roads throughout the steady-state capture zone via a type 3 (Cauchy) boundary that varies both temporally and spatially with road type and location. After calibrating the model from 1945 to 2002 to chloride concentrations using the weighted average of 5 Greenbrook production wells, the model was run to the year 2041 to assess future implications. Remediation strategies were also investigated via 6 predictive scenarios in which chloride applications were reduced by varying degrees. The results of this phase will be used by the RMOW in cost-benefit analyses of alternative de-icing approaches versus de-chlorination treatment of the well water.

Soils bear natural and artificial structures and sustain agricultural and biological activities. Understanding soil behaviour is the key to appropriating the benefits derivable from this material. Engineers are usually interested in the mechanical aspect of soil behaviour. This involves the study of volume change and shear response to applied stresses. In the past, soil shear and volume change behaviour were studied independently. But many practical problems involve shearing accompanied by volume change, therefore, it is desirable to consider this interaction in modelling soil behaviour. The critical state theory (Roscoe et al. 1958) was developed to combine both shear and volume change behaviour of soils. Early soil mechanics theories including the critical state theory, were developed for saturated soils. Because unsaturated soils are encountered in many situations, there is the need to adapt earlier theories or to formulate new ones for unsaturated soils. The major differences in the physical behaviour of saturated and unsaturated soils are due to an internal stress called matric suction formed at the air-water interface in the soil pores. Theories developed for unsaturated soil mechanics are based on the inclusion of the effect of matric suction on soil behaviour. In this study, the applicability of two major frameworks (i.e., critical state theory and unsaturated soil mechanics) to the study of agricultural soil behaviour was investigated. Soil behaviour was considered within a modified critical state framework that permits the application of critical state theories to an unsaturated soil. An experimental program involving tests in a modified state-of-the-art triaxial testing system was undertaken. Critical state soil parameters were obtained and state boundaries identified. The role of matric suction and soil structure on state parameters are presented. Changes in matric suction caused a shift (translation) in state boundaries, while changes in structure caused a rotation of the state boundaries. Results also showed that the assumption that matric suction is a constant variable depends on the stress level in the soil. Under low stress regimes, this assumption seems justifiable, however this is questionable under high stress regimes. This study also showed the importance of consideration of suction in the analysis of agricultural soil behaviour.

Elemental sulphur (S0) is produced from processing bitumen from the oil sands region, Alberta. Long term storage of this S0 is under consideration. The objective of the current study was to determine the controls on water migration in variably saturated S0 blocks. Based on visual observations of S0 blocks, they were characterized as a hydrophobic fractured porous media. Thus, measurements of the hydraulic characteristics, including porosity (n) and hydraulic conductivity (K) of the matrix and the fractured media, were undertaken. These data were used to create characteristic relationships of unsaturated K (Kunsat) and volumetric moisture content (è) change with change in positive injection pressure (Ø).<p>Analyses showed that the mean total matrix n (nm) was 0.094 ± 0.035 (n = 280), the mean n available for water migration (na) was 0.065 ± 0.044 (n = 8) and the mean (geometric) K for the matrix was 2.0 x 10-6 ± 2.1 x 10-6 ms-1. In the case of vertical fractures, the aperture frequencies were measured to be 2.5, 10.0 and 21.0 m-1 for fractures with apertures > 1.4, 1.4 to 0.6 and < 0.6 mm respectively while the frequency of horizontal fractures, were measured to be 1.7 and 3.7 m-1 for with apertures > 1.4, and < 1.4 mm respectively. The fracture n (nf) was determined to be 0.0135. è Ø relationships were determined for both the fractured and non fractured media. From these plots, water entry values of 9 mm and 1 m were determined for the fracture pore space and the matrix pore space, respectively.<p>Simulations of packer tests resulted in a bulk saturated K (Kb) values ranging from 8.5 x 10-5 to 2 x 10-4 ms-1 above 9 m depth and 3 x 10-6 to 1.5 x 10-5 ms-1 below 9 m depth. Coupled Kunsat Ø and è Ø relationships were used to conceptually describe water migration in S0 blocks under different precipitation and mounding conditions. These plots also showed that the Kb is dominated by the fractures.

Oligomers of soft and hard segments of unsaturated polyesters (UPE) were synthesized in two steps of esterification. For the hard segment, isophthalic acid was first reacted with 1,2-propanediol, then maleic anhydride was added for further esterification. For the soft segment, diethylene glycol was used to replace 1,2-propanediol. Oligomers of soft and hard segments were blended in different ratios, and then cured with various amount of styrene. Dynamic mechanical and the stress-strain properties of these cured UPEs were evaluated. The results indicated that both stress and strain were above the criteria of the inhibitors when the amount of hard segment oligomer was 30, 60 or 70 wt% of UPE, and the added styrene was 35 or 45 phr relative to UPE. The formula of 30 wt% hard segment, 70 wt% soft segment, and 45 phr styrene was selected for the following studies. Tetraethyl orthosilicate (TEOS) and poly(dimethyl siloxane) were incorporated into the uncured UPE resins via sol-gel process. Then fillers and 5, 10, 15, 20 or 30 wt% of magnesium hydroxide were blended with UPE resins and cured. Self-extinguished phenomenon was observed in the erosion tests when the amount of magnesium hydroxide was equal or higher than 15 wt% relative to UPE. After 101 days of nitroglycerin migration experiments, the migration rate and amount were significantly reduced for these filled specimens compared with the current formula of inhibitors. In addition, 2.5 or 5 phr of phenyl triethoxysilane (PhTES) relative to UPE was added together with TEOS to study the physical properties of the organic-inorganic hybrid materials. When the amount of PhTES was 2.5 phr, it was found that the miscibility between inorganic and organic components improved, and their stress- strain properties also satisfied the criteria of the inhibitors.

Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Greek alphabet delta in title. Includes bibliographical references (leaves 136-155). Available also in a digital version from Dissertation Abstracts.

Dissertation (Ph.D.)--Auburn University,2007. / Abstract. Vita. Includes bibliographic references (p.90-118).

Thesis (M.Sc.)--Memorial University of Newfoundland, 2002. / Bibliography: leaves 105-113.