Doctoral Theses and Dissertations

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Open Access
The utility of HPV typing and relative quantification of HPV-16 transcripts for monitoring HPV vaccine efficacy and improving colposcopy triage of women with abnormal cervical cytology.
(Faculty of Graduate Studies and Research, University of Regina, 2007-11-01) Antonishyn, Nick Anthony; Horsman, Greg; Kelln, Rod
Human papillomaviruses (HPV) can cause benign or malignant disease with the majority of infections without symptoms. The viral origin of cervical cancer is now proven with HPV proteins E6 and E7 defining part of the molecular basis of oncogenesis in vitro. Integration and/or malignant transformation of cervical cells in vivo are expected to be accompanied by the over-expression of HPV genes for E6 and E7 oncoproteins and a reduction of both expression for the L1 capsid protein and viral DNA. Cervical intraepithelial neoplasia (CIN) has been associated with particular HPV types that can be distinguished by DNA sequence differences. The research work studied two important aspects of HPV and its role in cervical disease. First, the distribution of HPV types and the epidemiology of HPV infection in a population of Saskatchewan women referred to a colposcopy clinic. Second, the potential of HPV-16 transcripts and HPV viral load for the detection of CIN. The most commonly identified genotype in patients with CIN grade 2 or worse was HPV-16 (46.7%) followed by HPV-31 (14.7%) and then HPV-18 (3.9%). The risk of CIN associated with HPV-18 infection, odds ratio 0.8 (95% CI, 0.4 to 1.7) is significantly lower than either the odds ratio of 6.3 for HPV-16 (95% CI, 3.6 to 11.0) or 4.3 for HPV-31 (95% CI, 1.8 to 12.6). Thus in Saskatchewan, the prevalence of HPV-31 is high whereas HPV-18 is associated with less clinical disease. Consequently, the efficacy the new cervical cancer vaccine, which target only HPV-16 and HPV-18, may be diminished in Saskatchewan’s population. Analysis of variance (P = 0.2) indicated no significant correlation between grade of CIN and HPV viral load. The presence of E6 RNA (P = 0.0002) and relative quantification of HPV-16 E6 transcripts (P < 0.0001) displayed the most significant median difference among the various grades of CIN when standardized to HPV viral load and human RNA and DNA levels. There was no correlation with L1 transcripts and cervical disease. Likelihood ratios indicate that the combination of Pap smear cervical cytology screening test with E6 relative quantification, on populations with higher cervical disease prevalence, would find more true positives than simply an additional Pap test. Using molecular testing for triage, HPV genotype information identifies 96% of women with CIN grade 2 or worse while eliminating 44% of women with CIN grade 1 or better. Information from the relative quantification of HPV-16 E6 transcripts identified 31.0% (n=13) of HPV-16 positive women with CIN grade 1 or better while retaining 92.4% of women with CIN grade 2 or worse. This work shows that there is diagnostic utility in relative quantification of HPV transcripts and that it benefits from standardization for variables such as the amount of HPV DNA and the total cellular nucleic acids. Relative quantification of HPV-16 E6 and HPV genotyping can be used to reduce medical procedures for women. HPV molecular tests could be useful in a cascade of diagnostic testing designed to refer women with cervical abnormalities for colposcopy, or treatment, while reducing the number of women needing triage.
Open Access
Another Radio is Possible: Community Radio, Media Reform and Social Change in Thailand
(Faculty of Graduate Studies and Research, University of Regina, 2007-12) Elliott, Patricia W.
An exploration of the political and cultural impact of community radio in Thailand, and of the global implications of challenges to the prevailing model of state-controlled broadcast frequency monopolies.
Open Access
A critical exploration of voluntary sector social policy advocacy with marginalized communities using a population health lens and social justice.
(Faculty of Graduate Studies and Research, University of Regina, 2008-12) DeSantis, Gloria Christina; Mulvale, James; Jeffery, Bonnie
There appears to be little data on the social policy advocacy work of the voluntary social service sector, also known as community-based organizations (CBOs), in Canada and their role in helping to create healthier communities. Research on this topic is timely in light of the following: shifting expectations of social service CBOs over the past few decades; questions about CBO-government relations; a growing importance of measuring the outcomes/impacts of the social service CBO sector; a need to alter free market ideology and introduce the counterweight of social justice principles to reduce health inequities; a growing interest in holistic policy development; growing awareness that social policies have health implications; and the Canadian welfare state is under transformation. My purpose was twofold: to explore the evolving nature of policy advocacy work undertaken by social service CBOs in Saskatchewan using a population health lens, and to examine the perceived outcomes/impacts of these processes on marginalized groups of people, CBOs, governments and communities using this lens. Using a critical inquiry methodology, qualitative data were collected through a multi-method approach. A case study design was adopted. An examination of the case study context comprised data collected through telephone interviews with 39 voluntary social service agencies from 18 communities throughout Saskatchewan, through government annual reports spanning 60 years and through observations of the political context. The case study included an examination of documents from a policy advocacy coalition, personal interviews with 17 ii individuals involved with the coalition, and observations of the coalition. Follow-up focus groups were conducted with these 17 interviewees. There were a number of findings. There has been growth in the number and diversity of social service CBOs over the past 30 years, government funding cuts and Canada Revenue Agency rules negatively affected CBOs, CBOs perceive policy advocacy is interconnected with other advocacy types, a sense of fear and vulnerability affect some advocacy participants, and of the 39 social service CBOs, 35 said they believed they contribute to people’s health/well-being through their daily work with the social determinants of health (e.g., poverty). A number of different types of advocacy processes were found to exist and some included marginalized people while others did not; CBOs’ choices about including people appeared to depend on a number of conditions (e.g., perception of participation barriers, sense of vulnerability). Interviewees described a variety of perceived outcomes/impacts of advocacy processes (e.g., learning, behaviour change, social connectedness, emotional reactions) in different spheres. The advocacy processes and their impacts were multiple, fluid and not totally predictable. A conceptualization of policy advocacy processes and population health was formulated as were implications and suggested actions for moving toward the creation of healthier communities through enhanced engagement in social policy making.
Open Access
Mediating the numbered treaties: eyewitness accounts of treaties between the Crown and Indigenous Peoples, 1871-1876.
(Faculty of Graduate Studies and Research, University of Regina, 2011) Krasowski, Sheldon Kirk; Wheeler, Winona; Brennan, William; Pitsula, James, M.; Stonechild, Blair; Coates, Ken
This thesis looks at the historical period of treaty-making in Western Canada when six numbered treaties were negotiated between Canada and the Anishnabeg, Cree, Saulteaux, and Assiniboine Nations between 1871 and 1876. The main interpretation of treaty-making during this period is that the treaty commissioners and Indigenous leadership experienced “cultural misunderstandings” and that Euro-Canadian witnesses to treaty did not understand the treaty relationship. As a result, most of the eyewitness accounts by Euro-Canadian fur traders, missionaries, journalists, settlers and government representatives have been ignored by historians. This thesis argues against cultural misunderstandings and shows that Euro-Canadian negotiators and eyewitnesses clearly understood the roles and responsibilities in the treaty relationship. Violations of treaty did occur as new settlers moved into treaty territory and government representatives became more concerned about financial restrictions than the promises made during the negotiations. However, during the treaty-making period, Euro-Canadians understood their obligations under the treaty relationship. This thesis analyzes previously underutilized primary documents and re-evaluates standard sources on the numbered treaties to show that during the treaty-making period, Euro-Canadians understood the expectations of Indigenous peoples in the treaty relationship.
Open Access
An Effective and Critical History of Canada’s National Standardized Testing Program
(Faculty of Graduate Studies and Research, University of Regina, 2011-03-31) Dagenais, Margaret Anne; Ryan, Heather; Brown, Douglas; Hart, Paul; Maeers, Mhairi; Rennie, Morina; Volante, Louis
This dissertation explores Canada‟s national large-scale testing program, the School Achievement Indicators Program (SAIP) and its successor, the Pan-Canadian Assessment Program (PCAP) using a methodology built on Foucault‟s theoretical concepts. The product of the research is a critical and effective history of the production of SAIP/PCAP within the Canadian social, political, and economic context. The study considers the work of Canadian scholars and commentators working in the field of largescale testing and the work of those working in aspects of education that are proximal to the field of interest. The research recognizes the key role of the investigator, the critical importance of investigator‟s proximity to the field, her struggles within the field; and it also recognizes the need of the investigator to step away from the obligation to argue a particular perspective. The study also explores standardized testing regimes operating in England and the United States as well as international testing programs to gather the effects of these correlative spaces on the Canadian experience. The outcomes of the research include the production of an understanding of how large-scale standardized testing was produced in Canada, its resultant effects of harmonization on curriculum, and the identification of possible research sites for further inquiry.
Open Access
Dealing With Uncertainty in Engineering and Management Practices
(Faculty of Graduate Studies and Research, University of Regina, 2011-07) Peng, Wei; Mayorga, Rene V.; Mehrandezh, Mehran; Henni, Amr; Deng, Dianliang; Hipel, Keith W.
A set of methodologies is proposed for dealing with uncertainties in five fields. These fields are: (1) traffic noise impact assessment, (2) hydraulic reliability assessment and reliability based optimization, (3) binary linear programming, (4) real-time multiple source water blending optimization, and (5) process control of an industrial rotary kiln. The proposed methods are applied to several engineering and management cases to demonstrate their explicabilities and advantages. In the field (1), an integrated approach is presented to assess traffic noise impact under uncertainty (Peng and Mayorga, 2008). Three uncertain inputs, namely, traffic flow, traffic speed and traffic components, are represented by probability distributions. Monte Carlo simulation is performed to generate these noise distributions. Further, fuzzy sets and binary fuzzy relations are employed in the qualitative assessment. Finally, the quantification of noise impact is evaluated using the probability analysis. In the field (2), two innovative approaches are developed under uncertainty (Peng and Mayorga, 2010e). One is to assess hydraulic reliability that accounting for the deterioration of both structural integrity and hydraulic capacity of each pipe; another is to design a reliability- based optimal rehabilitation/upgrade schedule that considering both hydraulic failure potential and mechanical failure potential. In these two approaches, all uncertain hydraulic parameters are treated as random values. The main methodologies used are: Monte Carlo simulation, EPANET simulation, genetic algorithms, Shamir and Howard’s exponential model, threshold break rate model, and two-stage optimization model. Eventually, two universal codes, the hydraulic reliability assessment code and the long-term schedule code,were written in MATLAB and linked with EPANET. In the field (3), an interval coefficient fuzzy binary linear programming (IFBLP) and its solution are built under uncertainty (Peng and Mayorga, 2010c, 2010d). In the IFBLP, the parameter uncertainties are represented by the interval coefficients, and the model structure uncertainties are reflected by the fuzzy constraints and a fuzzy goal. The solution includes a defuzzification process and a crisping process. An alpha-cut technique is utilized for the defuzzification process, and an interval linear programming algorithm is used to the crisping process. One mixed technique (links the alpha-cut technique and min-operator technique) is used to determine a single optimal alpha value on a defuzzified crisp-coefficient BLP. Finally, the IFBLP is converted into two extreme crisping BLP models: a best optimum model and a worst optimum model. Uncertainties in the field (4) include the modeling uncertainty and dynamic input uncertainty (Peng et al, 2010a, 2010b). This dissertation provides a fuzzy multiple response surface methodology (FMRSM) to deal with these kinds of uncertainties. In the FMRSM, the experimental data sets are fitted into the first quadratic models and their residuals are fitted into the second quadratic models; the multiple objectives are optimized using a fuzzy optimization method. Six scenarios are designed based on a real-time operation. The results show the FMRSM is a robust, computational efficient and overall optimization approach for the real-time multi-objective nonlinear optimization problems. In the field (5), a dual-response-surface-based process control (DRSPC) programming is developed to address the uncertainty and dynamic calcination process (Peng, et al, 2010f). Several response surface models are appropriately fitted for an industrial rotary kiln. The proposed approach is applied on a real case. The application shows that the proposed approach can rapidly provide the optimal and robust outputs to the industrial rotary kiln. Other properties of the proposed approach include a solution for the time delay problem and a statistical elimination of measurement errors.
Open Access
A Modified Dialectical Behaviour Therapy Skills Group for Multidiagnostic Suicidal Adolescents with Symptoms of BPD
(Faculty of Graduate Studies and Research, University of Regina, 2011-07) Tuttle, Megan Patricia; Shercliffe, Regan; Hampton, Mary; Loutzenhiser, Lynn; Asmundson, Gordon; Spooner, Marc; Gilbert, Merv
A substantial group of adolescents demonstrate behavioural patterns consistent with the DSM-IV-TR diagnosis of borderline personality disorder (BPD). In light of the paucity of empirically validated interventions for adolescents with BPD, there is a fundamental need to develop and assess novel treatments for this underserved population. Following the research evidence for the effectiveness of standard Dialectical Behavior Therapy (DBT) for adult outpatients as well as the growing evidence for the usefulness of modified DBT programs adapted for adolescents, the primary purpose of this study was to investigate the effect of a 12-week outpatient DBT skills group that included family members and that was provided as an adjunct to non-DBT individual therapy (i.e., Treatment As Usual) for multidiagnostic suicidal adolescent outpatients. This study also offered an opportunity to examine how DBT skills group intervention might be provided in a "real-world" community-based system of care. A natural consequence of conducting this type of research is having less rigorous control over facets of the investigation. In this study,process challenges impacted the research design, and, ultimately, the opportunity to reach valid conclusions about the effects of the DBT intervention on the basis of a pre-post research design and analysis. Preliminary results suggest that a DBT skills group intervention may be a useful intervention for adolescents but additional studies are required to validate the effectiveness of DBT with this population. Implications for treatment development, service delivery, and future research directions are discussed in light of the findings.
Open Access
An Examination of Leaf Morphogenesis In The Moss, Physcomitrella Patens
(Faculty of Graduate Studies and Research, University of Regina, 2011-08) Barker, Elizabeth Io; Ashton, Neil; Weger, Harold; Chapco, William; Dale, Janis; Cover, David
Physcomitrella patens is a simple model plant belonging to the bryophytes, which diverged from the tracheophytes approximately 500 million years ago. The leaves of the moss are similar in form to vascular plant leaves although leaves evolved independently in the bryophyte and tracheophyte lineages. Close examination of the morphology of Physcomitrella leaves and investigation of the morphogenetic processes that result in the leaf form and of the hormonal and genetic regulation of those processes will elucidate the evolutionary trajectory of moss leaves. Photomicroscopy and measurement of moss leaves were performed to provide detailed descriptions of leaves in strains of Physcomitrella that exhibited normal and aberrant morphology. Low concentrations of two major phytohormones, auxins and cytokinins, were applied to growing moss cultures to investigate their effects on leaf morphogenesis. A bioinformatic analysis of homologues of vascular plant genes that are involved in leaf development was performed to identify candidate genes that may have been co-opted for regulation of leaf morphogenesis during the early course of plant evolution. The transition from the basal leaf form to the adult form is gradual for all of the heteroblastic features of Physcomitrella leaves with the possible exception of the midrib. Low concentrations of exogenous auxin and cytokinin stimulate cell expansion and cell divisions respectively and auxin may be a key regulator of leaf heteroblasty. Homologues of almost all tracheophyte genes that are known to be involved in leaf morphogenesis are present in the Physcomitrella genome. However, few of the ii Physcomitrella homologues exhibit both a high degree of sequence similarity to the vascular plant genes and high levels of expression in leaves. Of these, class I and class II homeodomain-leucine zipper genes are predicted to play key roles in leaf development in the moss. Other genes may have been co-opted to regulate the processes of cell division, cell expansion and adaxialization/abaxialization of the midrib in bryophyte leaves. Preliminary models of auxin-cytokinin activity and of genetic and hormonal regulation of leaf morphogenetic processes in Physcomitrella provide testable hypotheses for further investigation.
Open Access
An Application of Health Behaviour Models to Diabetic Treatment Adherence: A Comparison of Protection Motivation Theory and The Theory of Planned Behaviour
(Faculty of Graduate Studies and Research, University of Regina, 2011-11) Janzen Claude, Jennifer Amy; Hadjistavropoulos, Heather; Admundson, Gordon; Sharpe, Donald; Cismaru, Magdalena; Swartzman, Leora C.
Diabetes is a medical condition in which affected individuals have relatively low adherence to the treatment regimen consisting of medications, diet, exercise, and blood glucose monitoring. Models of health behaviour such as Protection Motivation Theory (PMT; Rogers, 1983) and the Theory of Planned Behaviour (TPB; Ajzen, 1991) have been developed in order to understand the many factors proposed to influence health behaviours but have not been sufficiently applied to diabetes. Both PMT and TPB predict intention to perform health behaviours but focus on different cognitions relating to intention. In addition to predicting intention and behaviour, the models may also be valuable in predicting emotional responses as the cognitions are similar to those specified in models of anxiety. The purpose of the present study was to compare PMT and TPB models in capacity to predict intentions to adhere and diabetic treatment adherence (i.e.,diet, exercise, medication, blood glucose monitoring). A second objective was to examine the influence of anxiety within the models. Volunteers with Type 1 or 2 diabetes from across Canada (N = 418) completed online or paper questionnaires. Follow-up questionnaires assessing treatment adherence were also completed one and two weeks after the initial questionnaire. Participants were highly adherent to medication and blood glucose monitoring activities (for individuals with Type 1 diabetes); therefore, the models could not be tested for these activities due to a lack of variance. A large percentage of variance was accounted for by PMT and TPB in each of the treatment behaviours. For both TPB and PMT, the strongest paths were found between intention and treatment behaviour. Perceived behavioural control/self-efficacy was the strongest predictor of intention in the majority of the models. Subjective norms in TPB and perceived severity in PMT were not found to be statistically significant in the models. Anxiety constructs were found to mediate relationships between certain cognitions and intention and between cognitions and treatment adherence. Anxiety symptoms were found to be negatively associated with treatment adherence. The results serve to improve our understanding of treatment adherence in individuals with diabetes, and also inform interventions for individuals who have difficulties with treatment adherence.
Open Access
Dosimetric Characterization of a Waveguide-Based Exposure System for Laboratory Studies with Unrestrained Mice at 1.9 GHZ
(Faculty of Graduate Studies and Research, University of Regina, 2011-12) Wasoontarajaroen, Siriwat; Benedicenti, Luigi; Thansandote, Artnarong; Paranjape, Raman; Mehrandezh, Mehran; Mobed, Nader; Ungvichian, Vichate
It is essential for research on the biological effects of radiofrequency (RF) electromagnetic energy to be conducted using well-characterized exposure systems in order to ensure the reliability of research outcomes. Realizing this importance, a waveguide-based in vivo exposure system was developed at the Consumer and Clinical Radiation Protection Bureau of Health Canada for conducting laboratory studies with live mice exposed to RF electromagnetic energy. This thesis presents the important aspects and dosimetric characterization evaluation of the developed exposure system. The Health Canada in vivo exposure system consists of four identical cylindrical waveguide chambers, each with a plastic cage for housing the animal. The chamber is fed by circularly-polarized RF power in the 1.9 GHz cellular frequency band, and is vertically mounted so that the long axis of the animal is co-planar with the rotating incident electric field. Power sensors were used along with directional or hybrid couplers and a digital voltmeter for data acquisition for real-time dose rate monitoring. The exposure chamber was characterized to obtain its dosimetric information in three aspects including field intensity and pattern, influences of an exposed mouse, and chamber dose rate evaluation. The variations and pattern of the electric field intensity inside the mouse cage volume were analyzed. The impacts due to the presence of the exposed mouse, such as reflected power at chamber input ports and the axial ratio of the circularly-polarized field when impinging upon the animal, were investigated. Chamber dose rates quantified in terms of whole-body-average (WBA) specific absorption rate SAR), brain-average (BA) SAR and peak-spatial-average (PSA) SAR were evaluated. The evaluations were experimentally performed on mouse cadavers and live mice and computationally conducted on heterogeneous mouse models. The results obtained from experiments and computations were in fairly good agreement with each other. SAR data obtained from live-mouse exposures were found to be within the bounds derived from the dosimetric information obtained from experiments with mouse cadavers. Uncertainties in measured and computed results were estimated. The dosimetric information produced by this work supports the use of the Health Canada exposure system for carrying out laboratory studies with live mice. The data obtained from these biological studies would contribute to a concerted assessment of human health risks from exposure to RF energy emitted from wireless communication devices such as mobile phones, wireless fidelity (Wi-Fi) and Bluetooth devices.
Open Access
Kinetics of Carbon Dioxide Absorption into Aqueous Solutions of4-(Diethylamino)-2-Butanol and Blended Monoethanolamine and 4-(Diethylamino)-2-Butanol
(Faculty of Graduate Studies and Research, University of Regina, 2012-01) Sema, Teerawat; Idem, Raphael; Tontiwachwuthikul, Paitoon; Ibrahim, Hussameldin; Zhao, Gang; Husain, Iqbal; Chowdhury, Firoz Alam
Recently, global warming and climate change problems have begun to receive attention globally. One of the urgent policies is to control greenhouse gas emissions to the atmosphere. Among the greenhouse gases, CO2 is considered to be a major contributor due to its abundance. The absorption of CO2 into chemical solvents is one of the mostpromising technologies for capturing CO2 due to its capability of handling large amounts of exhaust stream. One of the key parameters for this technology is to use effective solvents. A newly developed amino alcohol solvent, 4-(diethylamino)-2-butanol (DEAB), is now being considered as a promising alternative solvent for capturing CO2 due to its energy efficiency for regeneration and high absorption capacity. The primary focus of this research is on developing comprehensive reaction rate/kinetics models that take into account the coupling between the chemical equilibrium, mass transfer, and chemical kinetics of all possible chemical reactions for the absorption of CO2 into aqueous solutions of DEAB and blended MEA-DEAB in order to explore the potential of these new formulated solvents for capturing CO2 in terms of reaction kinetics. The fundamental knowledge required for the kinetics study, such as the physical solubility of CO2 (Henry’s law constant), the physical diffusivity of CO2, the equilibrium solubility of CO2, and the CO2-amines equilibria, are also considered in this research. The physical solubility and physical diffusivity of CO2 in aqueous solutions of DEAB and blended MEA-DEAB were estimated via a N2O analogy, which consists of measuring the solubility and diffusivity of N2O instead of CO2. The developed predictive correlations for the solubility and diffusivity of N2O in these new formulated solvents provide good predictive results compared to the experimental results. The absorption capacity in terms of the equilibrium solubility of CO2 in aqueous solutions of DEAB was found to be very high (comparable with PZ) and higher than that of AMP, MDEA, MEA, and DEA. Furthermore, the equilibrium solubility of CO2 in an aqueous solution of blended MEA-DEAB was observed to be higher than that of MEA. This research also established the mathematical models for calculating the equilibrium solubility of CO2 in an aqueous solution of these new formulated solvents. The calculated CO2 equilibrium solubility results were found to fit well with the experimental results. Finally, the comprehensive reaction rate/kinetics models for CO2 absorption into aqueous solutions of DEAB and blended MEA-DEAB were successfully developed. The predicted CO2 absorption rates obtained from the models favourably fit with the experimental results. The reaction kinetics results show that: (i) the rate of CO2 absorption into DEAB is higher than that into MDEA, is comparable with that into AMP and DEA, and is lower than that into MEA and PZ, and (ii) the rate of CO2 absorption into blended MEA-DEAB is higher than that into MEA. Based on the results obtained from this research in terms of reaction kinetics and absorption capacity, it can be concluded that the aqueous solutions of DEAB and blended MEA-DEAB have good potential to be used as the alternative solvents for capturing CO2.
Open Access
Studies and Prevention of Carbon Steel Corrosion and Solvent Degradation During Amine-Based CO2 Capture from Industrial Gas Streams
(Faculty of Graduate Studies and Research, University of Regina, 2012-01) Wattanaphan, Pathamaporn; Idem, Raphael; Tontiwachwuthikul, Paitoon; Young, Stephanie; deMontigny, David; Raina, Renata; Attalla, Moetaz I.
This research is focused on simultaneous inhibition of carbon steel (1020) corrosion and oxidative monoethanolamine (MEA) degradation in a carbon dioxide (CO2) capture process from simulated post-combustion coal-fired flue gas, where components typically present in the flue gas partly contribute to such problems. Therefore, in this work, various additives were selected to study in the effects of flue gas composition on both carbon steel (1020) corrosion and oxidative MEA degradation. Sodium chloride (NaCl), ferrous chloride (FeCl2), and hydrochloric acid (HCl) were selected to represent different sources of chlorides in the flue gas. Sulphurous acid (H2SO3), sulphuric acid (H2SO4), and nitric acid (HNO3) were selected to represent the aqueous solutions of sulphur dioxide (SO2), sulphur trioxide (SO3), and nitrogen dioxide (NO2), respectively. In addition, sodium bisulfite (NaHSO3), sodium sulfite (Na2SO3), sodium sulphate (Na2SO4), and ferrous sulphate heptahydrate (FeSO4·7H2O) were additionally selected in the study of corrosion. All the experiments were conducted under the base-case conditions containing MEA, CO2, and O2. In the carbon steel (1020) corrosion study, the results illustrate that NaCl, HCl, Na2SO4, FeSO4·7H2O, H2SO4, and HNO3 all accelerated the corrosion process, while FeCl2 slowed down metal corrosion. Surprisingly, H2SO3, NaHSO3, and Na2SO3, either behaved as corrosion promoters or corrosion inhibitors depending strongly on their concentrations. Finally, the mixed additives were studied by mixing HCl, H2SO3, H2SO4, and HNO3. The modified power law rate equation of the systems containing all four additives provided an acceptable percentage of average absolute deviations (%AAD) of 8.6%. In the oxidative MEA degradation study, FeCl2, HCl, H2SO4, and HNO3 essentially accelerated oxidative solvent degradation. On the other hand, NaCl and H2SO3 (below 250 ppm) appeared to prevent MEA degradation. Finally, the mixed additives study was performed by mixing HCl, H2SO3, H2SO4, and HNO3 in the concentration ranges equivalent to the mixed additives in the corrosion study. The modified power law rate equation of the systems containing all four additives provided an acceptable %AAD of 9.4%. In the inhibition study, both carbon steel corrosion and oxidative solvent degradation were inhibited simultaneously by introducing various inhibitors. Inhibitor A prevented carbon steel corrosion and oxidative MEA degradation by behaving as a hydrogen ion (H+) scavenger. It provided the maximum efficiency of 88.9% inhibition on carbon steel corrosion and 97.3% inhibition on oxidative solvent degradation. Inhibitor B behaved primarily as an oxygen scavenger where it minimized carbon steel corrosion at the maximum of 92.4% inhibition and 59.9% inhibition on solvent degradation. Inhibitor C behaved as a free radical scavenger where it provided the maximum efficiency only at 42.7% inhibition on carbon steel corrosion but 92.6% inhibition on oxidative MEA degradation. Finally, the mixed inhibitors (A and C) were performed where the mixed inhibitors ratio III provided the best overall inhibitors’ performance at 90.2% inhibition for carbon steel corrosion and 65.2% inhibition for oxidative MEA degradation. In conclusion, this work helped to establish “ultimate” inhibitors that were able to inhibit corrosion and solvent degradation simultaneously, which was essentially a successful achievement.
Open Access
Application of Function Approximations to Reservoir Engineering
(Faculty of Graduate Studies and Research, University of Regina, 2012-02) Elmabrouk, Saber Khaled; Shirif, Ezeddin; Mayorga, Rene; Henni, Amir; Asghari, Koorosh; Mouhoub, Malek; Al-Khafaji, Ali
The need for function approximations arises in many branches of engineering, and in particular, petroleum engineering. A function approximation estimates an unknown function, which then finds an underlying relationship within a given set of input-output data. In this study, a Multiple Regression Analysis (MRA), Artificial Neural Network (ANN), and Least Squares Support Vector Machine (LS-SVM) are applied to address some of the most three important ongoing challenges in reservoir engineering. The three ongoing challenges are reservoir fluid properties in the absence of PVT analysis, average reservoir pressure and oil production prediction. 1. The PVT properties of crude-oil such as the bubble point pressure (P[subscript b]), oil formation volume factor (B[subscript ob]), dissolved GOR (R[subscript sob]) and stock tank vent GOR (R[subscript ST]) play a key role in calculating reserves as well as for identification of reservoir characteristics. The properties are traditionally determined from laboratory analyses of reservoir oil samples. In the absence of experimental analysis, empirical correlations or models can be used to estimate reservoir fluid properties. In this study, MRA, ANN and LS-SVM are applied to develop PVT models with which to estimate the P[subscript b], B[subscript ob], R[subscript sob] and R[subscript ST]. Unlike the present PVT models, the proposed models can be applied in a straightforward manner by using direct field data. Additional correlations or experimental analyses are unnecessary. 2. Insight into average reservoir pressure (P[subscript avg]), and its change over time, plays a critical role in reservoir development. However, in order to determine the P[subscript avg], the well is shut-in for a build up test, resulting in loss of production. In high permeability reservoirs,this may not be a significant issue, but in medium to low permeability reservoirs, the shut-in period during the entire test may last several weeks before a reliable reservoir pressure can be estimated. This loss of production, and cost of monitoring the shut-in pressure, is often unacceptable. It is of great practical value if the P[subscript avg] can be obtained from the historical production and reservoir pressure data without having to shut-in the well. Three different models (BP-ANN, ANN-GA and LS-SVM) are obtained to predict and interpolate P[subscript avg] without closing the producing wells. The results indicate the proposed approach has the ability to accurately interpolate and predict current average reservoir pressure by employing historical production data. 3. The prediction of oil reservoir production performance has been an on-going challenge for engineers. It is an essential component of petroleum reservoir management. Traditionally, numerical simulations and decline curve analysis have been used to predict a reservoir’s future performance based on its current and past performance. Reservoir simulation is very time consuming and offers a non-unique solution with a high degree of uncertainty. On the other hand, decline curve analysis fits the observed production rates of individual wells, groups of wells or an entire reservoir using mathematical functions to predict future production by extrapolating the declining function. In this study, ANN and LS-SVM are presented to predict the performance of oil production within water injection reservoirs. The historical production and injection data are used as inputs. The approach can be categorized as a new and rapid method with reasonable results. Another application of these models is that it can be utilized to find the most economical scenario of water injection to maximize ultimate oil recovery. This method could be a new window for fast simulators. It has reasonable accuracy, requires little data and can forecast quickly.
Open Access
The [Re]Construction of a Learner Self: A Phenomenological Study with Youth and Young Adults Postinvolvement in Criminal Behaviour
(Faculty of Graduate Studies and Research, University of Regina, 2012-03) Nelson, Rhonda LaVonne; Ryan, Heather; Kesten, Cyril; McNinch, James; Patenaude, Allan; Greenberg, Hirsch; Schonert-Reichl, Kimberly
This phenomenological research study had as its focus the concept of „self as learner‟ as an internal, complex process of self-discovery within human experience. It sought to illuminate, firstly, the meanings youth and young adults who had engaged in criminal behaviour and been unsuccessful in the K – 12 system had drawn from being part of the schooling experience and their perception of „self as a learner‟; and secondly, the meanings they had drawn from their current experiences of being learners after involvement in the development of a portfolio that represented in a concrete way their own personal knowledge, skills and attitudes. Transformative learning (Meziow, 1991) and the transtheoretical model of change (Prochaska, 2008) were complementary theoretical frameworks used to guide the study development. Congruent with the conception of how learning facilitates transformative change and the stages individuals go through within a change process as presented by the theories, each of the study participants had been faced with a disorienting dilemma surrounding an at risk lifestyle. Each demonstrated an openness to personal change by voluntary involvement in a community agency program utilizing the portfolio learning process involving self-evaluation, introspection, analysis, and synthesis concurrently with life skills programming. Through the reflective process that is part of the portfolio learning process, the participants [re]constructed their sense of themselves as learners through their personal meaning-making of their formal schooling experience and the evidence of their informal learning, in ways that support their positive engagement in ongoing learning. Five major distinctions in thematic content meanings emerged from the descriptions offered by the participants related to what it was like for them as a learner: 1. The school environment had a critical role in encouraging either success or failure. 2. The curricula, in its focus and scope, had a critical role in either maintaining exclusion through contextual disadvantage or facilitating social bonding and inclusion. 3. The personal relationships teachers either developed or avoided had a critical role in facilitating or derailing engagement with learning. 4. The substitution of peer influence for parental guidance and support had a critical role in introducing substance use and delinquent behaviours. 5. Emotion played a critical role in determining the extent to which factors either suppressed or encouraged the learner in learning. In addition, three fundamental findings concerning the broader context in which the lived experiences of the study participants emerged were identified as being congruent with the themes established in the literature review: (a) the role of systemic disadvantage in precluding learning of how society works; (b) the role of racism and prejudice in sustaining a perception of fear of youth who are perceived to not belong, even though those youth may themselves fear not belonging; (c) the role of learning environments that provide contextual and academic learning in lessening the effects of individual blame for lack of success as a learner.
Open Access
Randomized Controlled Feasibility Trial of a Self-Help Book for Health Anxiety
(Faculty of Graduate Studies and Research, University of Regina, 2012-03) Bovell, Candice Vanessa; Asmundson, Gordon; Hadjistavropoulos, Heather; MacLennan, Richard; Malloy, David; Norton, G. Ron
The purpose of this feasibility study was to determine the efficacy of a cognitive-behaviour therapy (CBT) self-help book for health anxiety titled, It’s Not All in Your Head (Asmundson & Taylor, 2005) relative to a wait-list control. It was hypothesized that using a CBT self-help book would be a more efficacious treatment than wait-list control. Health anxiety is marked by anxious preoccupation about having a physical disease, based on the catastrophic misinterpretation of innocuous bodily sensations. It is associated with unpleasant physiological, behavioural, cognitive, and affective symptoms. When elevated, health anxiety affects an individual‘s interpersonal relationships, especially with his or her doctor, and increases health utilization of primary care, diagnostic tests, and secondary care resources (Conradt, Cavanagh, Franklin, & Rief, 2006). Although once regarded as a chronic disorder resistant to treatment and often associated with a poor prognosis (Avia, Ruiz, Olivares, & Crespo, 1996; Barsky, Bailey, Fama, & Ahern), there are now several empirically-supported treatment options (Taylor, Asmundson, & Coons, 2005). In particular, CBT treatments that aim to identify maladaptive thoughts and behaviours and replace them with healthy and adaptive ones, have been proven effective, and are the treatment of choice for many (Furer, Walker, & Freeston, 2001). The development of CBT programs for treating elevated health anxiety has progressed to the point where widely accessible self-help options are available. In this trial, 14 volunteers experiencing health anxiety were recruited. Participants were randomly assigned to either an 8-week self-help book treatment (SHB; n = 10) during which they read the self-help book and received therapist guidance sessions or an 8-week wait-list control group (WLC; n = 4). Health anxiety, depression, and general health symptoms were assessed at pre-, mid-, and post-treatment. T tests were used for statistical analyses and intention-to-treat analyses were employed. Relative to WLC, SHB participants reported minor reductions in health anxiety symptoms after 3 weeks of treatment and significant reductions in health anxiety and depression symptoms post-treatment. Unfortunately, due to the small sample size and lack of statistical power, some analyses could not be performed. These findings provide preliminary support the trial hypothesis and can be used to inform a future, large-scale, randomized controlled trial. Participants had mostly positive feedback about the treatment, but reported difficulty completing treatment in 8 weeks and a poor therapeutic alliance. Procedural difficulties were encountered during the trial that limit the generalizability of the results. A clinically supported, CBT-based, self-help treatment for health anxiety will potentially improve the psychological and social lives of many individuals and reduce the financial and time expenditures of mental health care providers.
Open Access
The Challenges and Opportunities of Using a Competency Based Education Model in Social Work Education
(Faculty of Graduate Studies and Research, University of Regina, 2012-03) Ramirez, Nelida; MacLean, Michael; Sanchez, Miguel; Schantz, David; Schick, Carol; Hunter, Garson; Rogers, Gayla
The ongoing expansion of neo-liberal globalization is affecting the milieu of both social work education and its practice and, in some countries, is actively promoting the adoption of Competency Based Education (CBE) models for education. To date, research addressing the question of whether CBE provides a useful theoretical framework in designing and implementing a curriculum for a Bachelor of Social (BSW) Work program has been sporadic. Given the importance of the ‘CBE question’ for education in general, and social work education in particular, the nature and process of current CBE curriculum designs for social work programs needs to be well understood, and the researchbase on this subject needs to increase. Considering the lack of research on the topic, this dissertation focuses on ascertaining why CBE models have been adopted in social work education internationally and analyses how the process of applying those models to curricula design and implementation has been carried out. Thus, the research seeks to answer the question: Does the CBE model serve as a useful theoretical framework to design and implement a Bachelor Social of Work program curriculum? The overall goal of this research is to advance to the dialogue and debate about the CBE issue within the social work academic community. It is, therefore, important to consider the views and opinions of professors who support utilizing CBE models and those who oppose it as well. The research also provides a conceptual framework concerned with key terms used throughout the dissertation. As well, the study presents theoretical information related to the major conceptual underpinnings of topics and contents related to the postsecondary education environment including its learning process, and approaches to curriculum development. The theoretical and philosophical foundations of CBE and classifications of competencies, CBE curriculum’s challenges, and criticisms of the CBE model are provided. Finally, an overview of the history of social work education in different countries is included. The research approach must be identified as a generic qualitative study. The methods used to gather research data included document analysis, face- to-face interviewing, and Information Communication Technology (ICT) tools, including e-interviewing or interview conducted by e-mail and a website blog. The data results were formally conceptualized and coded in several categories. These categories were created by scrutinizing and reflecting on the practical experiences furnished by social work educators who detailed the implications, challenges, and opportunities of using a CBE model for social work curriculum design. The conclusions of the research indicate that many factors are pressuring or providing the impetus for the use of CBE in curriculum design and implementation for social work programs. Given this context, it is vital for academics within social work faculties to analyze and discuss the opportunities and challenges presented by the need for curricula change and renewal. Such a proactive approach to meeting the challenge of change is in sharp contrast to a passive strategy of responding to both external and internal pressures for curriculum change and renewal.
Open Access
Nurses and Their Work in Hospitals: Ruled by Embedded Ideologies and Moving Discourses
(Faculty of Graduate Studies and Research, University of Regina, 2012-03) Urban, Ann-Marie; Ryan, Heather; Hart, Paul; Schick, Carol; Riemer, Harold; Cameron, Brenda L.
Nursing originates from societal beliefs about women‟s roles of self-sacrifice and obedience situated within a history of patriarchal control. Unfortunately, these ideologies continue to influence and shape nurses‟ work in hospitals. Within the literature, several dominant discourses construct hospitals and nurses‟ work in hospitals as chaotic and challenging while nurses are conceptualized as stressed and fatigued. Overcrowding, increasing patient acuity, budget constraint, and chronic understaffing are only some of the issues nurses face in their every day and night work. Because of these problems, nurses are expected to care for patients in the hallways; manage with minimal staffing; and simply absorb the work associated with acutely ill patients. Nurses actively participate and take up these discourses as their work. Patriarchal assumptions and nurses‟ endless compromise and accommodation have resulted in the normalization of hospital problems as just part of nurses‟ work. Prevailing ideologies and institutional discourses make invisible, and taken-for-granted, how this work contributes to sustaining the hospital‟s power. External relations contribute to influencing and organizing nurses and their work. Using institutional ethnography and a poststructuralist perspective; this research relies on my experience, historical research, participant observation and interviews to reveal how institutional discourses have framed nurses‟ work in hospitals and how nurses actively participate in perpetuating and vivifying them.
Open Access
Conceptually-Based Strategy Use Investigating Underlying Mechanisms and Development Across Adolescence and into Early Adulthood
(Faculty of Graduate Studies and Research, University of Regina, 2012-03) Dube, Adam Kenneth; Robinson, Katherine; Arbuthnott, Katherine; Oriet, Christopher; Seaman, Charles; Smith-Chant, Brenda
Researchers have used inversion and associativity problems (e.g., 2 × 8 ÷ 8, 3 + 19 − 17, respectively) to assess whether or not individuals have the conceptual understanding that addition and subtraction and multiplication and division are inverse operations (i.e., the inversion concept, Robinson & Ninowski, 2003; Starkey & Gelman, 1982) and whether or not they understand that numbers can be decomposed and recombined in various ways and still result in the same answer (i.e., the associativity concept, Canobi, Reeve, & Pattison, 1998; Robinson, Ninowski, & Gray, 2006). It is not known when the development of these two concepts reaches adult levels. Furthermore, it is not known whether the application of these concepts during problem solving requires individuals to interrupt the execution of well-practiced procedural knowledge (e.g., Siegler & Araya, 2005). In the present study, 40 adolescent participants per grade from Grades 7, 9, and 11 and 40 adult participants who had graduated from high school the previous academic year solved multiplication and division inversion and associativity problems. Also, participants completed a task that measured whether the execution of the inversion shortcut or associativity strategy interrupted the execution of computational strategies. The results suggest that inversion shortcut and associativity strategy use increase in Grade 9, that inversion shortcut use approaches adult levels before associativity strategy use, and that the execution of both conceptually-based strategies interrupts computational strategies. Therefore, the present study identifies adolescence as an important developmental period for inversion shortcut and associativity strategy use and provides the first evidence that applying conceptual mathematical knowledge to problem solving requires the interruption of procedural mathematical knowledge.
Open Access
Dietary Niche and Foraging Ecology of a Generalist Predator, Double-Crested Cormorant (Phalacrocorax Auritus): Insight Using Stable Isotopes
(Faculty of Graduate Studies and Research, University of Regina, 2012-04) Doucette, Jennifer Lee; Somers, Christopher; Brigham, Mark; Wissel, Bjoern; Fallat, Shaun; Hobson, Keith
The ability of predator populations to expand their ranges and adapt to new environments is often attributed to having a generalist dietary strategy, which is thought to be represented both at the population and individual level. Cormorants (Phalacrocorax spp.) are considered to be opportunistic generalists capable of using a wide variety of aquatic prey. This reputation is partially responsible for the global conflict between piscivorous cormorants and fish harvesters, which is one of the most widespread wildlife management issues in history. Despite the persistent belief that cormorants adversely affect economically important fish populations, relatively little is known about their trophic ecology and habitat use. Stable nitrogen and carbon isotopes are popular tools for studying food webs, and offer a comprehensive assessment of diet, trophic position, and ecological niche when combined with traditional diet analyses. However, the interpretation of isotope data may be confounded by variation in the lipid content of sample tissues. No validated lipid-normalization procedures are currently available for any cormorant species, or any fish-eating birds. As such, I first determined the effect of lipids on the stable carbon and nitrogen isotopes (δ13C and δ15N) values in cormorant tissues, and tested three published lipid-normalization models on stable isotope signatures in double-crested cormorant (P. auritus) muscle and liver tissues. The presence of lipids in cormorant muscle and liver altered the stable isotopes values, indicating corrections were required. However, the effects of lipids in cormorants were unpredictable and thus violated a major assumption of published lipid-normalization models. As a result, lipids must be chemically removed from cormorant muscle and liver tissue. I then examined the diet and trophic position of breeding populations of double-crested cormorants from three different lakes. The results revealed that cormorants generally occupied top-predator positions and relied heavily on pelagic prey in all food webs examined. The isotopic values of cormorants and pelagic predatory fish were sometimes similar, suggesting that dietary overlap is possible. To determine whether cormorants are true dietary generalists I studied double-crested cormorants from breeding colonies spanning three major ecoregions. Analyses of stomach contents revealed that at the population level cormorant diet varied widely by location, likely reflecting local food-web structure. However, within populations individuals were much more specialized than expected. Temporal shifts in δ13C and δ15N values in cormorant tissues with different turnover rates (muscle vs. liver) indicated that foraging varied among populations. The dietary niche occupied by cormorants will affect their interactions with fish, highlighting the importance of understanding their impacts to fish populations both at the population and individual level. Ultimately, my research has shown that cormorants do not consume prey indiscriminately, and instead may have more specific and uniform dietary niche requirements than previously considered. From a management perspective, cormorants should not be assumed to have negative effects on fish in all situations; however, further attention is required to determine the impacts of dietary overlap with sport fish. Ecologically, I have shown that generalist species can be much more consistent and specialized than previously considered. Further, individuals within generalist species may be highly specialized, which will change the overall effects of the population on other species in the food web.
Open Access
Optical Transitions in Amorphous Semiconductors
(Faculty of Graduate Studies and Research, University of Regina, 2012-04) Orapunt, Farida; O'Leary, Stephen; Benedicenti, Luigi; Laforge, Paul; Palmer, Ron; Huber, Garth; Sabarinathan, Javshri
In this thesis, a quantitative analysis of the optical response of an amorphous semiconductor is presented. The entire analysis is cast within the framework of an empirical model for the valence band and conduction band density of states functions, that captures the basic features expected of these functions. A novel aspect of this analysis is the introduction of the density of localized valence band and conduction band electronic states and the establishment of a means of evaluating these densities from knowledge of the density of states functions coupled with the locations of the valence band and conduction band mobility edges. The determination of the contributions to the joint density of states function attributable to the various types of optical transitions, as a function of the location of these mobility edges, is another novel feature of this analysis. This formalism is then applied in order to determine the spectral dependence of the normalized dipole matrix element squared average corresponding to such a semiconductor. A means of determining the spectral dependence of the optical absorption coefficient is also provided. Finally, this formalism is applied to the specific case of plasma enhanced chemical vapor deposition deposited hydrogenated amorphous silicon, this being the most widely used amorphous semiconductor at present. It is found that the mobility gap value suggested by Jackson et al. [Physical Review B, vol. 31, pp. 5187-5198, 1985] is discordant with the experimentally measured optical response. It is also found that the effective masses associated with the electrons and holes within plasma enhanced chemical vapor deposition are greater than those that occur in crystalline silicon. The prospects for future work in this field, that builds upon the results presented herein, are commented upon.