Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2007.

This study focuses on the impact of HIV/Aids on secondary school educators who are affected by the HIV/Aids pandemic. The study seeks to understand how the pandemic has impacted on educators and identify support needs of educators affected by HIV/Aids. Many educators are negatively affected by HIV/Aids due to the fact that their family members, loved ones, friends, learners and colleagues may be ill, dying or affected by HIV and Aids. Educators are personally and professionally affected by HIV/Aids. Personally many educators are emotionally, socially, spiritually and physically affected. Professionally many are negatively impacted as educator absenteeism rises, morale is lowered and professional roles become more complex. There are very few avenues of support for educators who are affected by the HIV pandemic. To determine how high school educators are affected and what their subsequent support needs are, this study followed a phenomenological design. Fourteen high school educators were interviewed. All participants taught at township schools in the Free State and were affected by the HIV pandemic. The data were coded with regard to how these educators were affected by the pandemic and what support they wished for. According to this study's findings, educators in township secondary schools in the Free State are personally and professionally affected. Their experiences are mostly negative. They wish for support from the Department of Education, school management, their colleagues and the community. Examples of requested support include training and counselling programmes, supportive attitudes and additional educators so that they might be assisted to cope with the HIV/Aids pandemic challenges. / Thesis (M.Ed.)--North-West University, Vaal Triangle Campus, 2009.

Cervical cancer is a multifactorial disease. Infection by oncogenic types of the human papillomavirus (HPV) is the major environmental risk factor and host genetic susceptibility also influences disease development. The aim of this thesis is to identify and analyse risk genes involved in the genetic predisposition to cervical carcinoma. A unique and extensive population-based affected sib-pair (ASP) material and a large case-control sample were used in the investigations. In paper I the human leukocyte antigen (HLA) class II DQB1 and DRB1 loci are confirmed, for the first time in a family-based material, as genetic susceptibility factors for cervical cancer. It is also proposed that the HLA class II DPB1 locus independently contributes to risk of developing disease. In addition, no evidence is found for an involvement of the class I HLA-B and HLA-A loci in the genetic predisposition. Paper II conclude that the Fas receptor –670 single nucleotide polymorphism (SNP) do not have a major impact on the susceptibility to cervical carcinoma in situ in the Swedish population. In paper III we show that interactions between the HPV16 E6 gene subtype and host HLA class II genotype potentially occur during infection and disease progression. Paper IV suggests that three chromosomal regions, 9q32, 12q24 and 16q24, contain risk factors of low to moderate effects on cervical cancer development. In paper V linkage signals are further identified between a 9q32 gene encoding the thymic stromal co-transporter (TSCOT) and the disease in ASPs with mean age over 30.5 years at diagnosis within the sib-pair. These findings are important contributions towards understanding more about the aetiology of this complex cancer. The identification of new susceptibility regions opens up for further characterisation, replication and candidate gene analysis.

Due to a policy of no release, oil sands process-affected water (OSPW) produced by the surface-mining oil sands industry in North Eastern Alberta, Canada, is stored on-site in tailings ponds. There is concern regarding the toxic effects of OSPW on aquatic organisms. Knowledge of the chemical composition and toxicity of OSPW is limited. Research is necessary for potential remediation and release of OSPW back into the environment. Due to the large volume and persistency of OSPW, active efforts are necessary for the remediation of OSPW before release and habitat reclamation. Currently, ozonation is considered one possible method for remediation of OSPW by reducing the concentrations of dissolved organic compounds, including naphthenic acids (NAs), which are considered among the primary toxic constituents. However, further work is needed to evaluate the effectiveness of ozonation in reducing the toxicity of OSPW and to ensure that ozonation does not increase the toxicity of OSPW. The overall objective of this work was to determine the toxic effects of OSPW on endocrine disruption and embryo development, using both in vitro and in vivo models, and the effectiveness of ozone treatment for reducing the toxicity of OSPW. In the first study, untreated and ozone-treated OSPW were examined for effects on sex steroid production using the H295R cell line steroidogenesis Assay. The results indicate that exposure to untreated OSPW can significantly decrease synthesis of testosterone (T) and increase synthesis of 17β-estradiol (E2) by 0.55±0.06 and 2.0±0.13-fold, respectively, compared to that of control groups (ρ < 0.05). These effects were due to increased aromatase enzyme activity and decreased E2 metabolism. The results also suggest that ozonation is an effective treatment to reduce concentrations of NAs in OSPW without altering steroidogenesis. In the second study, the T47D-kbluc (estrogen responsive) and MDA-kb2 (androgen responsive) cell assays were used to determine whether OSPW might act as either agonists or antagonists of the estrogen receptor (ER) or androgen receptor (AR), respectively. The estrogenic responses to untreated OSPW were significantly greater by 2.6±0.22-fold compared to control group (ρ < 0.05). Exposure to untreated OSPW produced significant antiandrogenic response in the presence of 0.01, 0.05 and 0.1 nM T by 16±6.5%, 47±7.6% and 75±9.7%, respectively, of that of the corresponding concentrations of T alone (ρ < 0.05). The results suggest that compounds in the dissolved organic fraction of OSPW have estrogenic and anti-androgenic properties, acting as ER agonists and/or AR antagonists. Ozonation of the OSPW partially mitigated the antiandrogenicity but had no effect on the estrogenicity of OSPW. In the third study, the endocrine-disrupting effects of OSPW and ozone-treated OSPW were determined by quantifying relative changes in the abundances of transcripts of genes along the brain-gonad-liver (BGL) axis in male and female fathead minnows (Pimephales promelas). The results indicate that OSPW has endocrine-disrupting effects at all levels of BGL axis and these effects of impaired expression of genes along the BGL axis are sex specific. For example, exposure to OSPW resulted in significantly greater abundances of transcripts of vtg (Vitellogenin), chg-l (Choriogenin L) and chg-h (Choriogenin H minor) by 4.9±1.2, 5.4±1.5 and 3.4±0.78-fold, respectively, compared to those of control groups (ρ < 0.05) in livers from male fathead minnow. However, in livers from female fathead minnows, exposure to OSPW resulted in significantly lesser abundances of transcripts of vtg, chg-l and chg-h by 0.002±0.0011, 0.022±0.007 and 0.036±0.024-fold, respectively, compared to those of control fish (ρ < 0.05). Ozonation of OSPW attenuated the effects on abundances of transcripts of some genes, and the attenuation was more prominent in males than in females. However, impact of ozonation on endocrine-disrupting effects of OSPW was less evident than in the in vitro studies described in Chapter 2 and 3. The results also provide a mechanistic basis for the endocrine-disrupting effects of OSPW from other studies, including impaired reproduction of fathead minnows exposed to OSPW. In the final study the effects of untreated, ozone-treated, and activated charcoal-treated OSPW (OSPW, O3-OSPW, and AC-OSPW) on the survival, growth, and development of embryos of fathead minnows were determined. Compared to the control group, which had an embryo survival rate of 98±2.1%, survival was significantly less when exposed to OSPW (44±7.1%; ρ < 0.05). Eggs exposed to untreated OSPW exhibited a significantly greater rate of premature hatching, and embryos exhibited more frequent spontaneous movements. Incidences of hemorrhage (50±3.4%), pericardial edema (56±7.1%), and malformation of the spine (38±5.4%) were significantly greater in embryos exposed to OSPW compared to control group (ρ < 0.05). Significantly greater concentrations of ROS (1.7±0.11-fold), and greater abundances of transcripts cyp3a, gst, sod, casp9, and apopen (2.4±0.34, 2.2±0.26, 3.1±0.74, 3.3±0.57 and 2.4±0.25-fold, respectively) compared to control groups (ρ < 0.05), indicated that exposure to OSPW caused oxidative stress, which can result in damage to mitochondria and promote activation of caspase enzymes and apoptotic cell death. Removal of dissolved organic constituents in OSPW by ozone treatment, or by activated charcoal, significantly attenuated all of the adverse effects associated with untreated OSPW. The results suggest that the organic fraction of OSPW can negatively impact the development of fathead minnow embryos through oxidative stress and apoptosis, and that ozonation attenuates this developmental toxicity. Overall, the findings from the research described in this thesis provide novel and important insights into the toxicity and mechanisms of the toxicity of OSPW with respect to endocrine disruption and development of embryos of fish. In addition, the research provides compelling evidence that ozonation might be an effective method for accelerating the remediation of OSPW. The results of the research might help regulators develop effective strategies for reclamation, remediation and potential release of OSPW back to the environment.

Studien undersöker hur familjehemsföräldrar och deras familjer påverkas av uppdraget som familjehem. Studien undersöker även hur familjehemsföräldrar hanterar egna uppkomna känslor, samt vilket stöd de erhåller i uppdraget. En kvalitativ metod användes där sju familjehemsföräldrar från fyra familjehem intervjuades utefter en semistrukturerad intervjuguide. Respondenternas uppgifter har analyserats utifrån systemteori, copingteori, utvecklingsekologi och teoretiska begrepp. Studiens resultat visar att uppdraget tar mycket tid och energi, vilket påverkar familjehemsföräldrarna, de biologiska barnen och deras vardag på en rad olika sätt. Familjehemsföräldrarna upplever att de själva och deras biologiska barn fått ett annat synsätt på livet. Familjehemsföräldrar upplever svårigheter kring att få tag på socialtjänsten och att socialsekreterare ofta byts ut under uppdragen. Möten med de placerade barnen och deras nätverk ger upphov till mycket glädje, men de kan också ge upphov till känslor av frustration och otillräcklighet. Familjehemsföräldrarna använder sig av olika copingstrategier för att hantera egna känslor som uppkommer kring uppdraget. Resultatet visar också att både formell och informell stöttning är viktigt. / This study examines how foster parents and their families are affected by the foster care commitment. The study also examines how foster parents handle their own emotions, and what support they receive. A qualitative method was used where seven foster parents from four foster families were interviewed using a semi structured interview guide.The participant’s answers were analyzed through a theoretical approach that included system theory, coping theory, development ecology and theoretical concepts. The result shows that care commitment takes much time and energy,which affects everyday life, foster parents and their biological children in a number of ways. Foster parents experience that themselves and their own children received a new perspective on life. Foster parents experience difficulties around getting hold of the social services, and that social workers are being replaced during commitment. The encounter with the placed children and their network generates a lot of joy, but can also cause feelings of frustration and inadequacy. Foster parents are using various coping strategies to manage their own emotions that emerge related to the foster care commitment, the result also shows that both formal and informal support are important.

The In Situ Aquifer Test Facility (ISATF) has been established on Suncor Energy Inc’s (Suncor) oil sands mining lease north of Fort McMurray, Alberta to investigate the fate and transport of oil sands process-affected (PA) water in the Wood Creek Sand Channel (WCSC) aquifer. In 2008, the ISATF was used for preliminary injection experiments in which 3,000 and 4,000 L plumes of PA water were created in the WCSC. Following injection, the evolution of the plumes was monitored to determine if naphthenic acids (NAs) naturally attenuated in the WCSC and if trace metals were mobilized from the aquifer solids due to changes in redox conditions. Post-injection monitoring found groundwater velocities through the aquifer were slow (~3-10 cm/day) despite hydraulic conductivities on the order of 10-3 m/s. While microbes in the WCSC were capable of metabolizing acetate under the manganogenic/ferrogenic redox conditions, field evidence suggests naphthenic acids behaved conservatively. Following the injections, there was an apparent enrichment in the dissolved concentrations of iron, manganese, barium, cobalt, strontium and zinc not attributable to elevated levels in the PA injectate. Given the manganogenic/ferrogenic conditions in the aquifer, Mn(II) and Fe(II) were likely released through reductive dissolution of manganese and iron oxide and oxyhydroxide mineral coatings on the aquifer solids. Because naphthenic acids make up the bulk of dissolved organic carbon (DOC) in the injectate and are apparently recalcitrant to oxidation in the WCSC, some question remains as to what functioned as the electron donor in this process.

The In Situ Aquifer Test Facility (ISATF) has been established on Suncor Energy Inc’s (Suncor) oil sands mining lease north of Fort McMurray, Alberta to investigate the fate and transport of oil sands process-affected (PA) water in the Wood Creek Sand Channel (WCSC) aquifer. In 2008, the ISATF was used for preliminary injection experiments in which 3,000 and 4,000 L plumes of PA water were created in the WCSC. Following injection, the evolution of the plumes was monitored to determine if naphthenic acids (NAs) naturally attenuated in the WCSC and if trace metals were mobilized from the aquifer solids due to changes in redox conditions. Post-injection monitoring found groundwater velocities through the aquifer were slow (~3-10 cm/day) despite hydraulic conductivities on the order of 10-3 m/s. While microbes in the WCSC were capable of metabolizing acetate under the manganogenic/ferrogenic redox conditions, field evidence suggests naphthenic acids behaved conservatively. Following the injections, there was an apparent enrichment in the dissolved concentrations of iron, manganese, barium, cobalt, strontium and zinc not attributable to elevated levels in the PA injectate. Given the manganogenic/ferrogenic conditions in the aquifer, Mn(II) and Fe(II) were likely released through reductive dissolution of manganese and iron oxide and oxyhydroxide mineral coatings on the aquifer solids. Because naphthenic acids make up the bulk of dissolved organic carbon (DOC) in the injectate and are apparently recalcitrant to oxidation in the WCSC, some question remains as to what functioned as the electron donor in this process.

The heat-affected zone (HAZ) is the most common region of weld failures. The weld failures are directly related to the microstructure. Microstructure control of the HAZ is crucial to weld quality and prevention of weld failures. However, publications on modeling the development of the HAZ are relatively limited. Moreover, no efforts have been made to predict the HAZ microstructures in real-time. The primary goal of this research is to present a methodology to enable real-time predictions of microstructure evolution in the HAZ and its mechanical properties. This goal was achieved by an approach based on materials science principles and real-time sensing techniques. In this study, the entire welding process was divided into a series of sub-processes. Real-time multiple measurements from multiple sensors were incorporated into the sub-processes. This resulted in an integrated welding system upon which the predictions for the final HAZ microstructure are based. As part of the integrated system, the microstructural model was used to predict the TTT curves, volume fractions of the decomposition products, and hardness numbers of the heat-affected zones of steel alloys. Actual welds were performed under two different sets of conditions, and the resulting experimental data were compared with predictions made using the microstructural model. The predicted and experimental microstructure and hardness are found to be in good agreement, indicating that the microstructural model can be used in real applications. This research can act as an important component of future research to enable physics-based flexible control of welding. / text

As part of their reclamation plan, oil sands operators propose to transfer the mature fine tailings, which are a by-product of the oil sands extraction process, to open-pits and cap them with either a layer of surface water or oil sands process-affected waters (OSPW). These oil sands pit lakes are expected to develop habitats with productive capabilities comparable to natural lakes in the region. The studies presented in this thesis evaluate the potential impact of OSPW and its associated constituents [i.e. acid-extractable organics (e.g. naphthenic acids; NAs) and salts] on the reproductive physiology of adult fathead minnow (Pimephales promelas). Through 14-21 day fathead minnow reproduction assays it was demonstrated that aged OSPW can impair spawning, lower plasma sex steroid concentrations, and reduce male secondary sexual characteristics. The acid-extractable organics in OSPW were demonstrated to have an adverse effect on fathead minnow reproductive physiology. Other studies showed that the high salinity which characterizes OSPW also influences toxicity. When fathead minnows were exposed to the OSPW extract and 700 mg/l of NaHCO3, the NaHCO3 reduced the inhibitory effects of the extract on the numbers of reproductive tubercles and plasma testosterone levels by reducing the uptake of NAE to the fish. Embyro and larval bioassays also revealed that NaHCO3 reduces the acute toxic effects of the OSPW extract. An assessment of a wild population of fathead minnows inhabiting an OSPW pond determined that there were differences in the condition factor (CF), gonadosomatic indices (GSIs), liver somatic indices (LSIs), male secondary sexual characteristics, and 11-ketotestosterone concentrations in the fathead minnows from the OSPW pond relative to fish collected at reference sites. The opercula of fathead minnows from the OSPW pond also differed from those of reference fish and an examination of the gills revealed that were a number of proliferative and degenerative alterations relative to reference fish. Collectively, these studies demonstrate that aged OSPW has the potential to negatively affect the reproductive physiology of fathead minnows and suggest that aquatic habitats with high NAs concentrations (>10 mg/l) will have adverse effects on fish. / Canadian Natural Resources Ltd., Canadian Water Network, Canadian Oil Sands Network for Research and Development (CONRAD), Imperial Oil Ltd., NSERC, Shell Canada Energy, Suncor Energy Inc., Syncrude Canada Ltd., and Total E&P Canada

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