title: Bidirectional AC-DC Converters Using One Cycle Control (OCC) for Electric Vehicles

contributor:
Jain, Praveen K.
Electrical and Computer Engineering

subject:
Reactive power
One cycle control
Bidirectional AC-DC Converters
Interleaved converters

abstract: Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2016-07-12 22:55:21.356

abstract:
The electric vehicle (EV) market has seen a rapid growth in the recent past. With an increase in the number of electric vehicles on road, there is an increase in the number of high capacity battery banks interfacing the grid. The battery bank of an EV, besides being the fuel tank, is also a huge energy storage unit. Presently, it is used only when the vehicle is being driven and remains idle for rest of the time, rendering it underutilized. Whereas on the other hand, there is a need of large energy storage units in the grid to filter out the fluctuations of supply and demand during a day. EVs can help bridge this gap. The EV battery bank can be used to store the excess energy from the grid to vehicle (G2V) or supply stored energy from the vehicle to grid (V2G ), when required. To let power flow happen, in both directions, a bidirectional AC-DC converter is required. This thesis concentrates on the bidirectional AC-DC converters which have a control on power flow in all four quadrants for the application of EV battery interfacing with the grid.
This thesis presents a bidirectional interleaved full bridge converter topology. This helps in increasing the power processing and current handling capability of the converter which makes it suitable for the purpose of EVs. Further, the benefit of using the interleaved topology is that it increases the power density of the converter. This ensures optimization of space usage with the same power handling capacity. The proposed interleaved converter consists of two full bridges. The corresponding gate pulses of each switch, in one cell, are phase shifted by 180 degrees from those of the other cell.
The proposed converter control is based on the one-cycle controller. To meet the challenge of new requirements of reactive power handling capabilities for grid connected converters, posed by the utilities, the controller is modified to make it suitable to process the reactive power. A fictitious current derived from the grid voltage is introduced in the controller, which controls the converter performance. The current references are generated using the second order generalized integrators (SOGI) and phase locked loop (PLL). A digital implementation of the proposed control ii
scheme is developed and implemented using DSP hardware. The simulated and experimental results, based on the converter topology and control technique discussed here, are presented to show the performance of the proposed theory.

abstract: The thesis work is a part of an on-going project, which might culminate into a commercial product. Hence, until the project is completed in its entirety, it is best to keep the thesis restricted.

abstract: M.A.Sc.


title: Please Stop Rubbing Your Relationship In My Face(book): An Investigation of Online Romantic Social Comparison

contributor:
MacDonald, Tara K.
Psychology

rights: Queen's University's Thesis/Dissertation Non-Exclusive License for Deposit to QSpace and Library and Archives Canada

rights: ProQuest PhD and Master's Theses International Dissemination Agreement

rights: Intellectual Property Guidelines at Queen's University

rights: This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.

subject:
social networking sites
Facebook
social comparison
romantic relationships
romantic social comparison

abstract: Thesis (Master, Psychology) -- Queen's University, 2016-07-13 01:01:54.309

abstract: It is well-documented that social networking sites such as Facebook set the stage for social comparison. Such comparison has been linked to a number of negative outcomes including envy, negative moods, and lower self-esteem. The present research aims to extend current understanding of online social comparison by investigating how it pertains to romantic relationships. I hypothesized that for individuals high in attachment anxiety (compared to those low in this construct), online romantic social comparison might be related to negative consequences—which, in the current project, was operationalized as lower mood/affect and state self-esteem. Further, I hypothesized that there would be an interaction between attachment anxiety and relationship insecurities on these negative outcomes, such that the expected difference of attachment anxiety would be more pronounced under conditions priming relationship insecurities, relative to a control condition. Two experiments were conducted, one of which focused on single individuals, and the second focusing on individuals who were themselves in dating relationships. The paradigms of each entailed experimental manipulation of a key relationship-related variable (for single individuals, pessimism for future relationships; for dating individuals, the presence or absence of rejection threat), subsequent exposure to romantic content from Facebook, and finally, measures of affect and state self-esteem. I discovered partial support for the hypothesis that some single individuals—particularly those with higher, rather than lower, attachment anxiety—do indeed report feeling more negative moods and lower state self-esteem following exposure to romantic online content, in contrast to single individuals who had instead viewed neutral online content. The association between attachment anxiety and negative outcome was especially pertinent if individuals had been primed to believe that their own future romantic prospects were grim, or if attention had been drawn to their singleness. Among dating individuals, less support for hypotheses was found; however, exploratory post-hoc analyses revealed a promising (albeit weak) trend indicating that reinvestigation of the current hypotheses would be prudent.

abstract: M.Sc.


title: The Dark Personality and Job Success in the United States Army: Use of Interpersonal Manipulation in the Workplace

contributor:
Fekken, G. Cynthia
Psychology

subject:
Manipulation
Dark Triad
Personality
Army
Job Success

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2016-07-15 10:49:24.683

abstract:
This dissertation relates job desires and outcomes to the Dark Personality (Psychopathy, Machiavellianism, Narcissism, Low Agreeableness, Low Honesty-Humility) in the United States Army.  It purports that individuals high on the Dark Personality desire more power, money, and status, and that they obtain jobs that afford them these luxuries by using manipulation at work.  Two pilot studies used samples of United States Army members to create and test index variables: Dark Personality, Total Manipulation in the workplace, Desire for Job Success, and Total Job Success in the Army.  Individual personality traits, manipulation tactics, and job desires were examined in secondary analyses.
Using a sample of 468 United States Army Members, central analyses indicated that Army members high on the Dark Personality desired Job Success.  Likewise, army members higher on the Dark Personality used more Manipulation tactics at work, including the egregious tactics.  Yet, using more Manipulation tactics at work predicted lower levels of Job Success in the Army.  Most manipulation tactics had a negative impact on Job Success, with the exception of soft tactics like Reason and Responsibility Invocation.  Together, these results indicate that selective use of soft manipulation predicted Job Success, but use of more manipulation tactics predicted less Job Success in the Army.  Curvilinear results indicated that being either very low or very high on the Dark Personality predicted more Job Success in the Army, whereas having intermediate levels of the Dark Personality predicted less Job Success.  Finally, possessing the Dark Personality and using more Manipulation tactics at work, together, predicted less Job Success in the Army.
Collectively, the results indicate that army members with intermediate levels of the Dark Personality want more powerful and high paying jobs, yet their strategy of manipulating their coworkers to move up the job ladder does not result in higher ranking, higher paying Army positions.  However, Army members highest on the Dark Personality achieved job success, defying the maladaptive influence that antisocial personality traits and manipulative behaviour had on job success for most Army members. Therefore, this dissertation indicates that successful corporate scoundrels exist in the Army, but there are few of them.

abstract: PhD


title: Tissue-specific bioscaffolds for adipose-derived stem/stromal cell expansion and delivery

contributor:
Flynn, Lauren E.
Chemical Engineering

subject:
Tissue engineering
Decellularization
Stem cells
Biomaterials

abstract: Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2016-07-27 15:34:12.62

abstract: Decellularized adipose tissue (DAT) is a promising biomaterial for soft tissue regeneration, and it provides a highly conducive microenvironment for human adipose-derived stem/stromal cell (ASC) attachment, proliferation, and adipogenesis. This thesis focused on developing techniques to fabricate 3-D bioscaffolds from enzymatically-digested DAT as platforms for ASC culture and delivery in adipose tissue engineering and large-scale ASC expansion. Initial work investigated chemically crosslinked microcarriers fabricated from pepsin-digested DAT as injectable adipo-inductive substrates for ASCs. DAT microcarriers highly supported ASC adipogenesis compared to gelatin microcarriers in a CELLSPIN system, as confirmed by glycerol-3-phosphate dehydrogenase (GPDH) enzyme activity, lipid accumulation, and endpoint RT-PCR. ASCs cultured on DAT microcarriers in proliferation medium also had elevated PPARγ, C/EBPα, and LPL expression which suggested adipo-inductive properties. In vivo testing of the DAT microcarriers exhibited stable volume retention and enhanced cellular infiltration, tissue remodeling, and angiogenesis. Building from this work, non-chemically crosslinked porous foams and bead foams were fabricated from α-amylase-digested DAT for soft tissue regeneration. Foams were stable and strongly supported ASC adipogenesis based on GPDH activity and endpoint RT-PCR. PPARγ, C/EBPα, and LPL expression in ASCs cultured on the foams in proliferation media indicated adipo-inductive properties. Foams with Young’s moduli similar to human fat also influenced ASC adipogenesis by enhanced GPDH activity. In vivo adipogenesis accompanied by a potent angiogenic response and rapid resorption showed their potential use in wound healing applications. Finally, non-chemically crosslinked porous microcarriers synthesized from α-amylase-digested DAT were investigated for ASC expansion. DAT microcarriers remained stable in culture and supported significantly higher ASC proliferation compared to Cultispher-S microcarriers in a CELLSPIN system. ASC immunophenotype was preserved for all expanded groups, with reduced adhesion marker expression under dynamic conditions. DAT microcarrier expansion upregulated ASC expression of early adipogenic (PPARγ, LPL) and chondrogenic (COMP) markers without inducing a mature phenotype. DAT microcarrier expanded ASCs also showed similar levels of adipogenesis and osteogenesis compared to Cultispher-S despite a significantly higher population fold-change, and had the highest level of chondrogenesis among all groups. This study demonstrates the promising use of DAT microcarriers as a clinically relevant strategy for ASC expansion while maintaining multilineage differentiation capacity.

abstract: PhD


title: Challenges, Strengths and Opportunities Related to Implementing Comprehensive          Evidence-Based Guidelines on Breast Cancer Survivorship Care by Primary Care Physicians and Nurse Practitioners in Southeastern Ontario

contributor:
Aiken, Alice
Rehabilitation Science

subject:
evidence-based guidelines
primary care
survivorship care
family physicians
nurse practitioners
Breast cancer

abstract: Thesis (Ph.D, Rehabilitation Science) -- Queen's University, 2016-07-15 16:26:59.114

abstract:
Background
Many breast cancer survivors continue to have a broad range of physical and psychosocial problems after breast cancer treatment. As cancer centres move forward with earlier discharge of stable breast cancer survivors to primary care follow-up it is important that comprehensive evidence-based breast cancer survivorship care is implemented to effectively address these needs. Research suggests primary care providers are willing to provide breast cancer survivorship care but many lack the knowledge and confidence to provide evidence-based care.
Purpose
	The overall purpose of this thesis was to determine the challenges, strengths and opportunities related to implementing comprehensive evidence-based breast cancer survivorship guidelines by primary care physicians and nurse practitioners in southeastern Ontario.
Methods
This mixed-methods research was conducted in three phases: (1) synthesis and appraisal of clinical practice guidelines relevant to provision of breast cancer survivorship care within the primary care practice setting; (2) a brief quantitative survey of primary care providers to determine actual practices related to provision of evidence-based breast cancer survivorship care; and (3) individual interviews with primary care providers about the challenges, strengths and opportunities related to provision of comprehensive evidence-based breast cancer survivorship care.
Results and Conclusions
In the first phase, a comprehensive clinical practice framework was created to guide provision of breast cancer survivorship care and consisted of a one-page checklist outlining breast cancer survivorship issues relevant to primary care, a three-page summary of key recommendations, and a one-page list of guideline sources. The second phase identified several knowledge and practice gaps, and it was determined that guideline implementation rates were higher for recommendations related to prevention and surveillance aspects of survivorship care and lowest related to screening for and management of long-term effects. The third phase identified three major challenges to providing breast cancer survivorship care: inconsistent educational preparation, provider anxieties, and primary care burden; and three major strengths or opportunities to facilitate implementation of survivorship care guidelines: tools and technology, empowering survivors, and optimizing nursing roles. A better understanding of these challenges, strengths and opportunities will inform development of targeted knowledge translation interventions to provide support and education to primary care providers.

abstract: Awaiting publication of the 3rd and final paper in this manuscript style thesis.

abstract: PhD


title: Mnemosyne: Narrating a Pakhtun Student's Foreign Curricular Experience

contributor:
DeLuca, Christopher
Education

subject:
Curricular Experience
Study Abroad

abstract: Thesis (Master, Education) -- Queen's University, 2016-07-20 17:01:21.786

abstract:
Studying abroad is generally viewed as an opportunity for personal and educational transformation for students. In recent years, various studies have been conducted in the area of study abroad. Most of these studies primarily involve quantitative analyses, and do not fully explore the lived experience of this opportunity. Recently, researchers have started exploring the qualitative aspects and impact of studying abroad, but from an external perspective. This study attends to the phenomenon of a foreign curricular experience from an insider’s perspective and explicates the experience through a personal narrative.
Countries usually have educational curricula that serve their particular needs. The rise of the number of students studying abroad has made study abroad a lucrative industry but it has also increasingly exposed foreign students to curricula that are different than those of their countries of origin. Subjecting students to dissimilar, and sometimes competing, curricula interrupts their habitual ways of knowing and being. My study is a qualitative study that explores the foreign curricular experience of one Pakhtun student.
Specifically, through an autobiography, this study aims to explore how a foreign curricular experience acts as a ‘transitional space’ for a student and how it deeply affects her learning self and identity. This study contributes to the body of literature on the effects of a foreign curriculum on study abroad students by adding narrative to explain the lived experience of studying abroad.

abstract: M.Ed.


title: An Integrative Case Study of Positive Youth Development in a Recreational Community Sport Program

contributor:
Côté, Jean
Bruner, Mark W.
Kinesiology and Health Studies

subject:
Youth Sport
Sport Psychology

abstract: Thesis (Ph.D, Kinesiology & Health Studies) -- Queen's University, 2016-07-21 14:22:50.954

abstract:
Participation in organized activities is associated with many markers of positive youth development (PYD) such as improved self-esteem, social competence, and academic achievement (Mahoney et al., 2009). Sport is an extra-curricular activity that is particularly popular among youth, as nearly three quarters of Canadian children and adolescents are engaged in organized sport or physical activity (CFLRI, 2012). Much of the research in this area has examined sport programs which are explicitly structured to promote life skills or PYD outcomes; however, the sustainability of such programs has recently been called into question (Turnnidge, Hancock, & Côté, 2014).  The purpose of this program of research was to conduct an in-depth case study of a successful, sustainable community youth basketball league.
Study 1 was a qualitative descriptive exploration of coaches’ perceptions of the basketball league. This study provided a general overview of the structure and perceived benefits of the league, from the perspective of current coaches. Coaches highlighted the unique emphasis that the league places on fun and positive immediate sport experiences.
Study 2 expanded on selected themes from Study 1, namely, the salience of the league’s culture and tendency for former players to return to the league as volunteers. This study used an ethnographic approach wherein the first author volunteered as an assistant coach on a basketball team over the course of a six-month season. This approach enabled him to gain considerable first hand insight into the organizational culture of the basketball league.
The third and final study adopted a quantitative approach using both systematic observation and questionnaires to investigate the relationship between PYD outcomes and observed athlete behaviour during basketball games. A cluster analysis revealed the presence of two distinct groups of athletes characterized by relatively high and low perceptions of PYD outcomes, which were also associated with varying behavioural characteristics during competition.
The results of these three studies provide a detailed blueprint of a successful youth sport program that has been sustained over 60 years. While not without limitations, many characteristics of the league should prove useful in structuring youth sport programs in other contexts.

abstract: PhD


title: Governmentality gone wild: How the separation of sex workers from 'communities' contributes to violence against sex workers

contributor:
Salah, Patricia
Gender Studies

subject: sex workers' rights, missing and murdered, settler colonialism, law and legal studies

subject: sex work, Canada, governmentality, community, Ottawa, violence, feminism, IPA

abstract: Thesis (Master, Gender Studies) -- Queen's University, 2016-07-28 15:42:31.602

abstract: Sex workers are members of our communities, whether they are local or national communities. In law, mainstream media representations, and research sex workers are positioned as outside of or in opposition to communities. Even within marginalized communities sex workers are excluded when appeals to respectability politics are made. In this thesis I analyze three analytic sites from three areas of social life. The first chapter performs a textual analysis of The Bedford Decision (2013) and the resulting Protection of Communities and Exploited Persons Act (2014) as an examination of law. The second chapter is an analysis of filmic discourse on community, sex workers, and violence in the mainstream film London Road (2015) as an examination of mainstream media. The third chapter draws upon empirical research, i.e. in-depth interviews with three current and former sex workers in Ottawa, Canada and analyzes the transcripts using interpretative phenomenological analysis (IPA) to center how sex workers’ understanding of their work, community, and the laws and policies that are supposed govern and protect them. In my preface and conclusion I discuss some of the ethical dilemmas I encountered while conducting this research. My findings suggest that sex workers are being positioned and understood as outside of communities in ways that contribute to violence against sex workers. The implications of this research suggest that people who speak in the name of communities—communities in the sense of local neighborhood communities, activist communities, and national communities—need to recognize that sex workers are part of their communities and be accountable to ensuring they are treated as members. Researchers who conduct research on sex work and sex workers need to be accountable to their participants and the impacts their research may have on laws and policies. Sex workers are an over-researched population yet their voices are largely misappropriated or silenced in popular research and policy debates.

abstract: M.A.


title: Warming and Chronic High Nutrient Manipulations Yield Differing Legacy Effects on the Soil Microbial Community and Nutrient Pools in the Low Arctic

contributor:
Grogan, Paul
Biology

subject:
Soil Carbon
Climate Warming
Low Arctic
Soil Microbes

abstract: Thesis (Master, Biology) -- Queen's University, 2016-08-01 20:16:48.736

abstract: Climate warming is predicted to increase summer air temperatures in the Arctic, warming soils and enhancing microbial decomposition of soil organic matter. Given the size of the soil carbon stores in the Arctic, even a fraction of its release as CO2 to the atmosphere could result in a positive feedback to climate warming. Fertilizers have been used in the past to quickly increase soil solution nutrients pools to mimic predicted concentrations under climate warming. However, because it may have inadvertent affects on the soil microbial community, fertilizer-induced patterns in microbial decomposition may be unrealistic. This study aimed to better understand the proposed mechanism of enhanced microbial decomposition under nutrient addition and warming treatments to discern whether warming alone is enough to stimulate enhanced microbial decomposition, or if nutrients in excess (i.e. chronic high nutrient additions) are necessary to yield such a response. I investigated the impacts of 10 years of greenhouse summer warming, chronic low nutrient factorial addition (5 g N and 1g P m-2 year-1, respectively), and chronic high nutrient factorial addition (10 g N and 5g P m-2 year-1, respectively) treatments on a mesic birch hummock tundra ecosystem near Daring Lake, NWT, Canada. Soil microbial nutrient pools, soil solution nutrient pools, and microbial community structure were measured in the upper organic, lower organic, and uppermost mineral soil depth intervals of all treatment plots in Spring 2014. Interestingly, the low nutrient additions did not yield any significant trends, yet the warming treatment increased soil bacterial richness suggesting a legacy effect of warming from the previous summers. Enhanced microbial nutrient uptake occurred only in the high nutrient addition treatments, and did not significantly alter soil carbon at least within the ten year period of this experiment. Together, these results and the absence of significant impacts of the low nutrient and greenhouse warming treatments suggests that nutrient and carbon cycling in these low arctic soils may be resilient against climate warming, at least over the initial decades.

abstract: M.Sc.


title: Role of STAT1 and CXCL10 in the Tumour Immune Microenvironment of High-Grade Serous Ovarian Cancer

contributor:
Koti, Madhuri
Craig, Andrew W.
Biomedical and Molecular Sciences

subject:
CXCL10
CD8+ T Cells
Cancer
STAT1
Tumour Immune Microenvironment
Biomarkers
High-Grade Serous Ovarian Cancer

abstract: Thesis (Master, Biomedical & Molecular Sciences) -- Queen's University, 2016-07-25 11:40:37.845

abstract: High-grade serous ovarian cancer (HGSC) is the most prevalent epithelial ovarian cancer characterized by late detection, metastasis and resistance to chemotherapy. Previous studies on the tumour immune microenvironment in HGSC identified STAT1 and CXCL10 as the most differentially expressed genes between treatment naïve chemotherapy resistant and sensitive tumours. Interferon-induced STAT1 is a transcription factor, which induces many genes including tumour suppressor genes and those involved in recruitment of immune cells to the tumour immune microenvironment (TME), including CXCL10. CXCL10 is a chemokine that recruits tumour infiltrating lymphocytes (TILs) and exhibits angiostatic function. The current study was performed to determine the effects of differential STAT1 and CXCL10 expression on HGSC disease progression and TME. STAT1 expression and intratumoural CD8+ T cells were evaluated as prognostic and predictive biomarkers via immunohistochemistry on 734 HGSC tumours accrued from the Terry Fox Research Institute-Canadian Ovarian Experimental Unified Resource. The combined effect of STAT1 expression and CD8+ TIL density was confirmed as prognostic and predictive companion biomarkers in the second independent biomarker validation study. Significant positive correlation between STAT1 expression and intratumoral CD8+ TIL density was observed. The effects of enforced CXCL10 expression on HGSC tumour growth, vasculature and immune tumour microenvironment were studied in the ID8 mouse ovarian cancer cell engraftment in immunocompetent C57BL/6 mice. Significant decrease in tumour progression in mice injected with ID8 CXCL10 overexpressing cells compared to mice injected with ID8 vector control cells was observed. Multiplexed cytokine analysis of ascites showed differential expression of IL-6, VEGF and CXCL9 between the two groups. Endothelial cell marker staining showed differences in tumour vasculature between the two groups. Immune transcriptomic profiling identified distinct expression profiles in genes associated with cytokines, chemokines, interferons, T cell function and apoptosis between the two groups. These findings provide evidence that STAT1 is an independent biomarker and in combination with CD8+ TIL density could be applied as novel immune-based biomarkers in HGSC. These results provide the basis for future studies aimed at understanding mechanisms underlying differential tumour STAT1 and CXCL10 expression and its role in pre-existing tumour immunologic diversity, thus potentially contributing to biomarker guided immune modulatory therapies.

abstract: Research discussed in the thesis is still ongoing and have not yet been published in any scientific journal.

abstract: M.Sc.


title: Disruptive Threads and Renegade Yarns: Domestic Textile Making in Selected Women's Writing 1811-1925

contributor:
Ware, Tracy
English

subject:
Needlework
English literature
American Literature
Textiles
Canadian literature
Nineteenth Century
Women's Writing
Domesticity

abstract: Thesis (Ph.D, English) -- Queen's University, 2016-08-03 13:57:45.102

abstract: Images of domestic textiles (items made at home for consumption within the household) and textile making form an important subtext to women’s writing, both during and after industrialization. Through a close reading of five novels from the period 1811-1925, this thesis will assert that a detailed understanding of textile work and its place in women’s daily lives is critical to a deeper understanding of social, sexual and political issues from a woman’s perspective. The first chapter will explore the history of the relationship between women and domestic textile making, and the changes wrought to the latter by the Industrial Revolution. The second chapter will examine the role of embroidery in the construction of “appropriate” feminine gentility in Jane Austen’s Mansfield Park (1814). The third chapter, on Elizabeth Gaskell’s Cranford (1853), will explore how the older female body became a repository for anxieties about class mobility and female power at the beginning of the Victorian era. The fourth chapter will compare Sara Jeannette Duncan’s A Social Departure (1890) and Kate Chopin’s The Awakening (1899) to consider how later Victorian women both internalized and refuted public narratives of domestic textile making in a quest for “self-ownership.” The last chapter, on Martha Ostenso’s Wild Geese (1925), examines the corrosive, yet ultimately redemptive, relationships of a family of women trapped by abuse and degradation. For all five authors, images of textiles and textile making allow them to speak to issues that were usually only discussed within a community of women: sexuality, desire, aging, marriage, and motherhood. In all five works, textile making “talks back” to the power structures that marginalize women, and lends insight into the material and emotional circumstances of women’s lives.

abstract: PhD


title: Bullying Involvement and Adolescent Substance Use: A Study of Multilevel Risk and Protective Factors

contributor:
Craig, Wendy M.
Psychology

subject:
HBSC
Substance use
Bullying
Adolescence

abstract: Thesis (Master, Psychology) -- Queen's University, 2016-08-02 13:18:40.65

abstract: Bullying, frequent drunkenness, and frequent cannabis use are significant health-risk behaviours among youth. While many studies have demonstrated that bullying involvement may initiate a developmental pathway to both types of frequent substance use, there is a limited understanding of the connection between these behaviours. The presence of risk and protective factors within youths’ relationships and within their neighbourhoods may alter the associations between bullying involvement and both types of frequent substance use. A systemic approach is needed to assess the complex, social environments in which youth are embedded. The current thesis consists of two studies that examined the associations between bullying and both types of frequent substance use within the context of youths’ social environments. In Study 1, multilevel modeling was used to examine the associations between bullying and frequent substance use within the context of individual and neighbourhood risk factors. Our results indicated that the risk factors associated with both frequent drunkenness and frequent cannabis use exist at both levels, with neighbourhoods altering the association of individual risk factors. Moreover, bullying was a unique risk factor associated with both types of frequent substance use, whereas indirect associations were observed for victimization. Study 2 used a similar methodology to examine the association between bullying and both types of frequent substance use within the context of individual and neighbourhood protective factors. Once again, our results indicated that the protective factors associated with both types of frequent substance use exist at multiple levels, and that neighbourhoods altered the association of individual protective factors. Additionally, positive relationship characteristics interacted with the link between bullying and both types of frequent substance use. Together, these findings clarify the nature of the bullying-substance use link and emphasize the need to study adolescent development in context.

abstract: M.Sc.


title: Examining Cognitive Processing in Children with an Arithmetic Disability

contributor:
Berg, Derek
Education

subject:
Arithmetic Disability
Executive Functioning
Phonological Processing

abstract: Thesis (Master, Education) -- Queen's University, 2016-07-25 20:11:24.773

abstract: Currently there is no consensus as to the specific cognitive impairments that characterize mathematical disabilities (MD) or specific subtypes such as an arithmetic disability (AD). The present study sought to address this concern by examining cognitive processes that might undergird AD in children. The present study utilized archival data to conduct two investigations. The first investigation examined the executive functioning and working memory of children with AD. An age-matched achievement-matched design was employed to explore whether children with AD exhibit developmental lags or deficits in these cognitive domains. While children with AD did not exhibit impairments in verbal working memory or colour word inhibition, they did demonstrate impairments in shifting attention, visual-spatial working memory, and quantity inhibition. As children with AD did not perform more poorly than their younger achievement-matched peers on any of these tasks, impairments in specific areas of executive functioning and working memory appeared to reflect a developmental lag rather than a cognitive deficit. The second study examined the phonological processing performance of children with AD compared to children with comorbid disabilities in arithmetic and word recognition (AD/WRD) and to typically achieving (TA) children. Results indicated that, while children with AD did demonstrate impairments on all isolated naming speed tasks, trail making digits, and memory for digits, they did not demonstrate impairments on measures of phonological awareness, nonword repetition, serial processing speed, or serial naming speed. In contrast, children with AD/WRD demonstrated impairments on measures of phonological awareness, phonological short-term memory, isolated naming speed, serial processing speed, and the alphabet a-z task. Overall, results suggested that phonological processing impairments are more prominent in children with a WRD than children with an AD. Together, these studies further our understanding of the nature of the cognitive processes that underlie AD by focusing upon rarely used methods (i.e., age-matched achievement-matched design) and under-examined cognitive domains (i.e., phonological processing).

abstract: M.Ed.


title: Imputing accelerometer non-wear time when assessing children's moderate-to-vigorous physical activity

contributor:
Janssen, Ian
McIsaac, Michael
Community Health and Epidemiology

subject:
Non-Wear Time
Children
Accelerometer
Imputation

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2016-07-28 21:58:09.382

abstract:
BACKGROUND: Moderate-to-vigorous physical activity (MVPA) is an important determinant of children’s physical health, and is commonly measured using accelerometers.
A major limitation of accelerometers is non-wear time, which is the time the participant did not wear their device. Given that non-wear time is traditionally discarded from the dataset prior to estimating MVPA, final estimates of MVPA may be biased. Therefore, alternate approaches should be explored.
OBJECTIVES: The objectives of this thesis were to 1) develop and describe an imputation approach that uses the socio-demographic, time, health, and behavioural data from participants to replace non-wear time accelerometer data, 2) determine the extent to which imputation of non-wear time data influences estimates of MVPA, and 3) determine if imputation of non-wear time data influences the associations between MVPA, body mass index (BMI), and systolic blood pressure (SBP).
METHODS: Seven days of accelerometer data were collected using Actical accelerometers from 332 children aged 10-13. Three methods for handling missing accelerometer data were compared: 1) the “non-imputed” method wherein non-wear time was deleted from the dataset, 2) imputation dataset I, wherein the imputation of MVPA during non-wear time was based upon socio-demographic factors of the participant (e.g., age), health information (e.g., BMI), and time characteristics of the non-wear period (e.g., season), and 3) imputation dataset II wherein the imputation of MVPA was based upon the same variables as imputation dataset I, plus organized sport information. Associations between MVPA and health outcomes in each method were assessed using linear regression.
RESULTS: Non-wear time accounted for 7.5% of epochs during waking hours. The average minutes/day of MVPA was 56.8 (95% CI: 54.2, 59.5) in the non-imputed dataset, 58.4 (95% CI: 55.8, 61.0) in imputed dataset I, and 59.0 (95% CI: 56.3, 61.5) in imputed dataset II. Estimates between datasets were not significantly different. The strength of the relationship between MVPA with BMI and SBP were comparable between all three datasets.
CONCLUSION: These findings suggest that studies that achieve high accelerometer compliance with unsystematic patterns of missing data can use the traditional approach of deleting non-wear time from the dataset to obtain MVPA measures without substantial bias.

abstract: M.Sc.


title: Cognitive and Linguistic Factors of Reading  Arabic: the Role of Morphological Awareness in Reading

contributor:
Klinger, Don A.
Education

subject:
Reading
Morphological Awareness
Arabic

abstract: Thesis (Ph.D, Education) -- Queen's University, 2016-07-26 11:39:39.756

abstract:
Scientific reading research has produced substantial evidence linking specific reading components to a range of constructs including phonological awareness (PA), morphological awareness, orthographic processing (OP), rapid automatized naming, working memory and vocabulary. There is a paucity of research on Arabic, although 420 million people around the world (Gordon, 2005) speak Arabic. As a Semitic language, Arabic differs in many ways from Indo-European languages.
Over the past three decades, literacy research has begun to elucidate the importance of morphological awareness (MA) in reading. Morphology is a salient aspect of Arabic word structure. This study was designed to (a) examine the dimensions underlying MA in Arabic; (b) determine how well MA predicts reading; (c) investigate the role of the standard predictors in different reading outcomes; and (d) investigate the construct of reading in Arabic. This study was undertaken in two phases.
In Phase I, 10 MA measures and two reading measures were developed, and tested in a sample of 102 Grade 3 Arabic-speaking children. Factor analysis of the 10 MA tasks yielded one predominant factor supporting the construct validity of MA in Arabic. Hierarchical regression analyses, controlling for age and gender, indicated that the MA factor solution accounted for 41– 43% of the variance in reading.
In Phase II, the widely studied predictor measures were developed for PA and OP in addition to one additional measure of MA (root awareness), and three reading measures In Phase II, all measures were administered to another sample of 201 Grade 3 Arabic-speaking children. The construct of reading in Arabic was examined using factor analysis. The joint and unique effects of all standard predictors were examined using different sets of hierarchical regression analyses. Results of Phase II showed that: (a) all five reading measures loaded on one factor; (b) MA consistently accounted for unique variance in reading, particularly in comprehension, above and beyond the standard predictors; and (c) the standard predictors had differential contributions. These findings underscore the contribution of MA to all components of Arabic reading. The need for more emphasis on including morphology in Arabic reading instruction and assessment is discussed.

abstract: PhD


title: The Rotational Evolution and Magnetospheric Emission of the Magnetic Early B-type Stars

subject:
Stellar Winds
Binary Stars
Magnetospheres
Massive Stars
Magnetic Braking
Stellar Magnetism
Spectropolarimetry

abstract: Thesis (Ph.D, Physics, Engineering Physics and Astronomy) -- Queen's University, 2016-08-02 12:36:18.169

abstract: How do the magnetic fields of massive stars evolve over time? Are their gyrochronological ages consistent with ages inferred from evolutionary tracks? Why do most stars predicted to host Centrifugal Magnetospheres (CMs) display no H$\alpha$ emission? Does plasma escape from CMs via centrifugal breakout events, or by a steady-state leakage mechanism? This thesis investigates these questions via a population study with a sample of 51 magnetic early B-type stars. The longitudinal magnetic field \bz~was measured from Least Squares Deconvolution profiles extracted from high-resolution spectropolarimetric data. New rotational periods $P_{\rm rot}$ were determined for 15 stars from \bz, leaving only 3 stars for which $P_{\rm rot}$ is unknown. Projected rotational velocities \vsini~were measured from multiple spectral lines. Effective temperatures and surface gravities were measured via ionization balances and line profile fitting of H Balmer lines. Fundamental physical parameters, \bz, \vsini, and $P_{\rm rot}$ were then used to determine radii, masses, ages, dipole oblique rotator model, stellar wind, magnetospheric, and spindown parameters using a Monte Carlo approach that self-consistently calculates all parameters while accounting for all available constraints on stellar properties. Dipole magnetic field strengths $B_{\rm d}$ follow a log-normal distribution similar to that of Ap stars, and decline over time in a fashion consistent with the expected conservation of fossil magnetic flux. $P_{\rm rot}$ increases with fractional main sequence age, mass, and $B_{\rm d}$, as expected from magnetospheric braking. However, comparison of evolutionary track ages to maximum spindown ages $t_{\rm S,max}$ shows that initial rotation fractions may be far below critical for stars with $M_*>10 M_\odot$. Computing $t_{\rm S,max}$ with different mass-loss prescriptions indicates that the mass-loss rates of B-type stars are likely much lower than expected from extrapolation from O-type stars. Stars with H$\alpha$ in emission and absorption occupy distinct regions in the updated rotation-magnetic confinement diagram: H$\alpha$-bright stars are found to be younger, more rapidly rotating, and more strongly magnetized than the general population. Emission strength is sensitive both to the volume of the CM and to the mass-loss rate, favouring leakage over centrifugal breakout.

abstract: PhD


title: Walking with God through Nature: An Examination of John Flavel’s Behavioural Instructions on Matters Related to Christian Piety

subject:
John Flavel
Christian
Mystical
Piety
Puritan
History
Devotion
Ritual
Spirituality
Wilderness
Prayer
Meditation

abstract: John Flavel was a Reformed Puritan of the seventeenth-century who wrote a series of devotional guides that offered instructions drawn from Christian mystical traditions on how to improve religious activities as a means of ecstatically encountering God. Evaluating the efficacy of these instructions from a scientifically-based behavioural perspective, this study has found that Flavel’s techniques were likely helpful to his readers in facilitating socially normative ecstatic experiences through ordinary Christian practice.  Furthermore, discovering that Flavel promoted the use of these techniques for engaging with ecological materials in the wilderness and country-side, this essay proposes that Flavel introduced his readers to effectual manners that could help them ecstatically encounter God during the practice of meditational nature-based walks.


title: MIMU sensors for joint kinematic estimation: anatomical landmarking and frame correction

contributor:
Li, Qingguo
Mechanical and Materials Engineering

subject:
Optical Motion Capture
Joint Kinematics
Inertial Motion Capture
Biomechanics
Mechanical Engineering
Anatomical Landmarking

abstract: Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2016-08-08 12:53:07.45

abstract: The ability to capture human motion allows researchers to evaluate an individual’s gait. Gait can be measured in different ways, from camera-based systems to Magnetic and Inertial Measurement Units (MIMU). The former uses cameras to track positional information of photo-reflective markers, while the latter uses accelerometers, gyroscopes, and magnetometers to measure segment orientation. Both systems can be used to measure joint kinematics, but the results vary because of their differences in anatomical calibrations. The objective of this thesis was to study potential solutions for reducing joint angle discrepancies between MIMU and camera-based systems. The first study worked to correct the anatomical frame differences between MIMU and camera-based systems via the joint angles of both systems. This study looked at full lower body correction versus correcting a single joint. Single joint correction showed slightly better alignment of both systems, but does not take into account that body segments are generally affected by more than one joint. The second study explores the possibility of anatomical landmarking using a single camera and a pointer apparatus. Results showed anatomical landmark position could be determined using a single camera, as the anatomical landmarks found from this study and a camera-based system showed similar results. This thesis worked on providing a novel way for obtaining anatomical landmarks with a single point-and-shoot camera, as well aligning anatomical frames between MIMUs and camera-based systems using joint angles.

abstract: M.A.Sc.


title: Perylene Diimide Molecular Glass: Investigations of Charge Transport

subject:
traps
Molecular glass
mobility
n-type organic semiconductor
PDI
CELIV
electron transport
perylene diimide

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2016-07-27 21:06:09.619

abstract: A new glass-forming organic semiconductor material was synthesized using a known electron transport material, perylene diimide, and attaching it to a molecular glass in order to allow the material to be solution processed. Devices were made using a simple metal-semiconductor-metal structure and electrodes were selected to produce Schottky diodes. Experiments were carried out to characterize this new molecular glass perylene diimide. The new material shows evidence of traps, hysteresis, and other behaviours that are explored in this thesis. The material shows some potential as an electron transport layer with possibilities of memory storage behaviour.

abstract: M.Sc.


title: Investigating the Association Between Computer-Mediated Communication (CMC) and the Health of Canadian Young People: A Mixed Methods Study

contributor:
Davison, Colleen
Pickett, William
Michaelson, Valerie
Community Health and Epidemiology

subject:
adolescent health
computer-mediated communication
loneliness
social media

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2016-08-07 12:43:23.388

abstract: Canadian young people are increasingly more connected through technological devices. This computer-mediated communication (CMC) can result in heightened connection and social support but can also lead to inadequate personal and physical connections. As technology evolves, its influence on health and well-being is important to investigate, especially among youth. This study aims to investigate the potential influences of computer-mediated communication (CMC) on the health of Canadian youth, using both quantitative and qualitative research approaches. This mixed-methods study utilized data from the 2013-2014 Health Behaviour in School-aged Children survey for Canada (n=30,117) and focus group data involving Ontario youth (7 groups involving 40 youth). In the quantitative component, a random-effects multilevel Poisson regression was employed to identify the effects of CMC on loneliness, stratified to explore interaction with family communication quality. A qualitative, inductive content analysis was applied to the focus group transcripts using a grounded theory inspired methodology. Through open line-by-line coding followed by axial coding, main categories and themes were identified. The quality of family communication modified the association between CMC use and loneliness. Among youth experiencing the highest quartile of family communication, daily use of verbal and social media CMC was significantly associated with reports of loneliness. The qualitative analysis revealed two overarching concepts that: (1) the health impacts of CMC are multidimensional and (2) there exists a duality of both positive and negative influences of CMC on health. Four themes were identified within this framework: (1) physical activity, (2) mental and emotional disturbance, (3) mindfulness, and (4) relationships. Overall, there is a high proportion of loneliness among Canadian youth, but this is not uniform for all. The associations between CMC and health are influenced by external and contextual factors, including family communication quality. Further, the technologically rich world in which young people live has a diverse impact on their health. For youth, their relationships with others and the context of CMC use shape overall influences on their health.

abstract: M.Sc.


title: Vicarious Power: The Interpersonal Transference of Power

contributor:
Ji, Li-Jun
Psychology

subject:
negotiation
vicarious power
interpersonal transference

abstract: Thesis (Ph.D, Psychology) -- Queen's University, 2016-07-29 15:58:26.695

abstract: Previous research on power has predominantly focused on power as an intrapersonal process. Relatively little research, however, has investigated the interpersonal transference of power.  In the present research, I documented the vicarious power effect – people vicariously feel more powerful when their psychological connections with powerful figures were made salient. Compared to participants in the control conditions, who wrote about either a non-powerful figure with whom they felt psychologically connected or a powerful figure with whom they did not feel connected, participants writing about a powerful figure with whom they felt psychologically connected reported a higher level of power. This effect was true for both a real-life powerful figure (Study 1) and a powerful fictional character (Study 2). In Study 3, I found that, compared to participants in the control conditions (non-powerful but close, powerful but not close), participants writing about their experience of taking a picture together with a close and powerful person (close and powerful condition) made a lower counteroffer in a seller-buyer negotiation task.  Furthermore, in Study 4, I found that, compared to participants in the control conditions (non-powerful but close, powerful but not close), participants writing about a close and powerful person (close and powerful condition) were more likely to engage in self-beneficial lying behaviors and less likely to engage in other-beneficial lying behaviors. The research sheds light on vicarious psychological processes in general. Remaining issues and directions for future research are discussed.

abstract: PhD


title: Block Copolymers Containing a Low-Surface-Energy Block and Their Applications

contributor:
Liu, Guojun
Chemistry

subject:
Nanomaterials
Superhydrophobic
Block Copolymer

abstract: Thesis (Ph.D, Chemistry) -- Queen's University, 2016-07-29 11:37:39.428

abstract:
This thesis reports the synthesis and/or applications of three types of block copolymers that each bear a low-surface-energy block.
First, poly(dimethylsiloxane)-block-poly(2-cinnamoyloxyethyl acrylate) (PDMS-b-PCEA) was synthesized and characterized. Cotton coating using a micellar solution of this block copolymer yielded superhydrophobic cotton fabrics. X-ray photoelectron spectroscopy (XPS) and surface property analyses indicated that the PDMS block topped the polymer coating. Photocuring the cotton swatches crosslinked the underlying PCEA layer and yielded permanent coatings. More interestingly, hydrophilically patterned superhydrophobic cotton fabrics were produced using photolithography that allowed the crosslinking of the coating around irradiated fibers but the removal, by solvent extraction, of the coating on fibers that were not irradiated. Since water-based ink only permeated the uncoated regions, such patterned fabric was further used to print ink patterns onto substrates such as fabrics, cardboard, paper, wood, and aluminum foil.
Then, another PDMS-based diblock copolymer poly(dimethylsiloxane)-block-poly(glycidyl methacrylate) (PDMS-b-PGMA) was prepared. Different from PCEA that photocrosslinked around cotton fibers, PGMA reacted with hydroxyl groups on cotton fiber surfaces to get covalently attached. Further, different PGMA chains crosslinked with each other. PDMS-b-PGMA-coated cotton fabrics have been used for oil-water separations. In addition, polymeric nanoparticles were grafted onto cotton fiber surface before PDMS-b-PGMA was used to cover the surfaces of the grafted spheres and the residual surfaces of the cotton fibers. These two types of fabrics, coated by the block copolymer alone or by the polymer nanospheres and then the copolymer, were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), and water repellency analyses. A comprehensive comparative study was made of their performances in oil-water separation.
Finally, a fluorinated ABC triblock copolymer poly(acrylic acid)-block-poly(2-cinnamoyloxyethyl methacrylate)-block-poly(2-perfluorooctylethyl methacrylate) (PAA-b-PCEMA-b-PFOEMA) was used to
iii
encapsulate air nanobubbles. The produced air nanobubbles were thermodynamically stable in water and were some 100 times more stable than commercially available perfluorocarbon-filled microbubbles under ultrasound. These nanobubbles, due to their small sizes and thus ability to permeate the capillary networks of organs and to reach tumors, may expand the applications of microbubbles in diagnostic ultrasonography and find new applications in ultrasound-regulated drug delivery.

abstract: PhD


title: An investigation of sugar-sweetened beverage consumption among Canadian youth

contributor:
Davison, Colleen
Pickett, William
Community Health and Epidemiology

subject:
Youth
Soft drinks
North
Beverage

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2016-08-08 16:01:46.322

abstract:
Background: Consumption of sugar-sweetened beverages (SSBs) is an important public health problem in Canada, especially among adolescents. Estimates show that rates of SSB consumption are particularly high in the northern territories, especially in Nunavut. This is concerning given
that regular SSB consumption is associated with obesity, diabetes and tooth decay, among other health concerns.
Objectives: This thesis has two objectives. The first is to describe SSB consumption patterns among adolescents from Nunavut specifically, all three territories combined and the provinces.The second is to determine the association between individual and cumulative school food programs and SSB consumption.
Methods: Data were obtained from the Health Behaviour in School-aged Children study (HBSC); a cross-sectional survey of Canadian youth in grades 6-10. All frequencies for food and beverage consumption were obtained from a 7-day food frequency questionnaire. SSB consumption consisted of a composite measure including soft drinks, sports drinks and energy drinks. The types of school food programs were obtained from an administrative questionnaire filled out by each school’s Principal or delegate. Multilevel multivariate Poisson regression models were used to examine the associations between school food programs and SSB consumption.
Results: Youth from Nunavut consumed the most SSBs (53.1% in 2010 and 55.0% in 2014 were daily consumers), followed by youth from the territories (31.1% in 2010 and 27.0% in 2014), then youth from the provinces (24.3% in 2010 and 19.1% in 2014). No significant relationships were
found between school food programs and daily SSB consumption. Two school food programs were weakly associated with weekly SSB consumption: nutrition month activities (RR=0.93,CI=0.89, 0.98) and healthy options in the snack bar (RR=1.07, CI=1.01, 1.14).
Conclusions:Rates of SSB consumption were highest among Nunavummiut youth followed by youth from all three territories combined and then the provinces. Little association was found between school
food programs and SSB consumption among Canadian youth in grades 6-10. These findings point to the need for examining other determinants and potential areas for intervention, for reducing SSB consumption among Canadian youth, particularly in high consumer sub-populations.

abstract: M.Sc.


title: Adiposity, Sex Hormones, and Repetitive Element DNA Methylation in Healthy Postmenopausal Women

contributor:
King, Will D.
Friedenreich, Christine
Community Health and Epidemiology

subject:
Epidmiology
Epigenetics
Sex Hormones
Adiposity

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2016-08-08 12:12:30.315

abstract:
INTRODUCTION: Low levels of methylation within repetitive DNA elements, such as long interspersed nuclear element-1 (LINE-1) and Alu repeats, are believed to epigenetically predispose an individual to cancer and other diseases. The extent to which lifestyle factors affect the degree of DNA methylation within these genomic regions has yet to be fully understood. Adiposity and sex hormones are established risk factors for certain types of cancer and other illnesses, particularly amongst postmenopausal women.  The aim of the current investigation is to assess the impact of adiposity and sex hormones on LINE-1 and Alu methylation in healthy postmenopausal women.

METHODS: A cross-sectional study was conducted using baseline data from an ancillary study of the Alberta Physical Activity and Breast Cancer Prevention (ALPHA) Trial. Current adiposity was measured using a dual-energy x-ray absorptiometry (DXA) scan, computed tomography (CT) scan, and balance beam scale. Historical weights were self-reported in a questionnaire. Current endogenous sex hormone concentrations were measured in fasting blood serum. Estimated lifetime number of menstrual cycles was used as a proxy for cumulative exposure to ovarian sex hormones. Repetitive element methylation was quantified in white blood cells using a pyrosequencing assay. Linear regression was used to model the relations of interest while adjusting for important confounders.

RESULTS: Adiposity and serum estrogen concentrations were positively related to LINE-1 methylation but were not associated with Alu methylation. Cumulative ovarian sex hormone exposure had a “U-shaped” relation with LINE-1 regardless of folate intake and a negative relation with Alu methylation amongst low folate consumers. Androgens were not associated with repetitive element DNA methylation in this population.

CONCLUSION: Adiposity and estrogens appear to play a role in maintaining high levels of repetitive element DNA methylation in healthy postmenopausal women. LINE-1 methylation may be a mechanism whereby estrogen exposure protects against cardiovascular and neurodegenerative illnesses. These results add to the growing body of literature showing how the epigenome is shaped by our lifestyle choices. Future prospective studies assessing the relation between levels of repetitive element DNA methylation in healthy individuals and subsequent disease risk are needed to better understand the clinical significance of these results.

abstract: I ask that you restrict this thesis because the two manuscripts contained within it are currently under review for publication.

abstract: M.Sc.


title: Maternal and Paternal Growth Regulatory Factor Expression in Hybrid Sunfish

contributor:
Moyes, Christopher D.
Biology

subject:
Bluegill
Alternative Reproductive Strategies
Growth
Hybrid
Growth Regulatory Factors
Pumpkinseed
Sunfish

abstract: Thesis (Master, Biology) -- Queen's University, 2016-07-30 16:51:54.981

abstract: Unidirectional hybridization between bluegill (Lepomis macrochirus) and pumpkinseed (L. gibbosus) sunfish enables researchers to explore the relative expression of paternal and maternal alleles in hybrids. Past studies have found that the metabolic dysfunction in bluegill-pumpkinseed hybrids may be due to incompatibilities between nuclear and mitochondrial genomes. However, the consequences of hybridization on body size and muscle growth have not been examined. This topic is particularly interesting because hybrids grow larger than parentals despite the fact that they are often sired by smaller, precociously mature bluegills. In order to improve our understanding of growth dynamics in hybrid sunfish, I conducted real-time quantitative PCR using species-specific primers on the white muscle tissue of bluegills, pumpkinseeds, and hybrids collected from Lake Opinicon, ON. Five growth factors that have been linked to muscle growth and body size demonstrated similar expression for maternal and paternal alleles. While about half of the hybrids showed the same pattern with myogenin, about half showed very low levels of mRNA for the paternal (bluegill) gene. While this did not explain the heterosis seen in hybrids, it may explain the small body phenotype of the cuckholding bluegill males. I explored the upstream genetic structure of bluegill myogenin and established that four alleles exist within the population. Furthermore, I uncovered a relationship in hybrids between the proximal promoter/ 5’ UTR of myogenin and its transcript level. I found that the hybrids demonstrating low paternal myogenin expression unfailingly possessed A3 or A4 alleles, but future studies will be needed to reveal the molecular links between the genotype and the growth phenotype. A similar genotype-phenotype association was not obvious in parentals, even those that were homozygous for these alleles. Whether this relationship can provide insight into the genetic determinants of bluegill alternative mating strategies has yet to be determined.

abstract: Restrict until April 2017. More data is required for publication.

abstract: M.Sc.


title: Tilted Columnar Thin Film Coatings With Anisotropic Light Scattering Properties for Solar Energy Applications

contributor:
Robbie, Kevin
Mechanical and Materials Engineering

subject: Glancing Angle Deposition

subject: Bidirectional Reflectance Distribution Function

subject: Dye-Sensitized Solar Cells

subject: Directional Scattering

abstract: Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2016-08-08 17:39:09.119

abstract:
The main goal of this thesis is to show the versatility of glancing angle deposition
(GLAD) thin films in applications. This research is first focused on studying the
effect of select deposition variables in GLAD thin films and secondly, to demonstrate
the flexibility of GLAD films to be incorporated in two different applications: (1) as
a reflective coating in low-level concentration photovoltaic systems, and (2) as an
anode structure in dye-sensitized solar cells (DSSC).
A particular type of microstructure composed of tilted micro-columns of titanium
is fabricated by GLAD. The microstructures form elongated and fan-like tilted
micro-columns that demonstrate anisotropic scattering.
The thin films texture changes from fiber texture to tilted fiber texture by increasing
the vapor incidence angle. At very large deposition angles, biaxial texture forms.
The morphology of the thin films deposited under extreme shadowing condition
and at high temperature (below recrystallization zone) shows a porous and inclined
micro-columnar morphology, resulting from the dominance of shadowing over
adatom surface diffusion.
The anisotropic scattering behavior of the tilted Ti thin film coatings is quantified
by bidirectional reflectance distribution function (BRDF) measurements and is
found to be consistent with reflectance from the microstructure acting as an array
of inclined micro-mirrors that redirect the incident light in a non-specular reflection.
A silver-coating of the surface of the tilted-Ti micro-columns is performed to enhance the total reflectance of the Ti-thin films while keeping the anisotropic scattering
behavior. By using such coating is as a booster reflector in a laboratory-scale low-level
concentration photovoltaic system, the short-circuit current of the reference silicon
solar cell by 25%.
Finally, based on the scattering properties of the tilted microcolumnar
microstructure, its scattering effect is studied as a part of titanium dioxide
microstructure for the anode in DSSCs. GLAD-fabricated TiO2 microstructures
for the anode in a DSSC, consisting of vertical micro-columns, and combined
vertical topped with tilted micro-columns are compared. The solar cell with the
two-part microstructure shows the highest monochromatic incident photon to
current efficiency with 20% improvement compared to the vertical microstructure,
and the efficiency of the cell increases from 1.5% to 2% due to employing the
scattering layer.

abstract: PhD


title: When Interacting Online Leads to Taking Action Offline: Examining the Effects of Online Persuasion on IS Users’ Pro-Environmental Behaviours

contributor:
Gallupe, R. Brent
Management

subject:
Online persuasion
Green IS
Environemntal sustainability

abstract: Thesis (Ph.D, Management) -- Queen's University, 2016-08-05 19:17:06.121

abstract:
With the increasing attention towards the role of information systems (IS) as a vehicle to address environmental issues, IS researchers and practitioners have strived to leverage advanced Green IS innovations to persuade people to engage in environmentally responsible practices and support pro-environmental initiatives. Yet, existing research
reveals that the persuasion effects of Green IS designs remain equivocal. In particular, many design characteristics advocated in Green IS research can produce bi-directional changes in IS users’ attitudes and behaviours. To address this issue, this thesis drew upon the circumplex model of social values (S.H. Schwartz, 1992) to explain when and how
online persuasion designs come to affect people’s judgements on resource conservation
and environmental protection. Three sets of working propositions and specific hypotheses
were developed. Specifically, this research suggests that the use of an IS application can
elicit different value primes and draw IS users’ attentions to different motivational functions of engaging in suggested behavioural changes. It is expected that matching online persuasion appeals with IS users’ personal value priorities can increase users’ acceptance of online behavioural suggestions. Second, it is hypothesized that the persuasion effect tends to be weakened, as the system users become aware of the valuematching design in a given IS application. Third, it is proposed that different value primes presented in an IS application can result in different unintended effects on IS users’ global pro-environmental attitudes and motivations. The hypotheses were tested in the two pilot studies and two full-scale online experiments. The study findings generally support the main predictions of the hypotheses. On the one hand, this thesis providesiii empirical evidence that IS design for online persuasion can be instrumental in influencing IS users’ judgements on a range of resource conservation practices. On the other hand,
this work explains why the effectiveness of IS-enabled online persuasion attempts needs
to be measured not only in terms of the intended changes in a target behavioural domain but also in terms of unintended changes in people’s general environmental orientations. Findings in this research may bring a different perspective on understanding and assessing the influence of Green IS applications on IS users’ judgements and behaviou

abstract: The access restriction is requested for three reasons. First, the thesis involves the use of a stand-alone web application which was designed and developed by a commercial IS company. Making the thesis publicly available would prejudice the intellectual property rights of the company. Second, part of the study materials in this thesis was obtained obtained under a promise of confidentiality. Third, this thesis is due for publication as a scholarly article. Making it publicly available would potentially prejudice the blind review policy in peer review process.

abstract: PhD


title: Multivariate Techniques in Biomechanical Analysis

contributor:
Deluzio, Kevin J.
Mechanical and Materials Engineering

subject: Multivariate Biomechanics

abstract: Thesis (Ph.D, Mechanical and Materials Engineering) -- Queen's University, 2016-08-03 15:53:40.518

abstract:
This work outlines the theoretical advantages of multivariate methods in biomechanical data, validates the proposed methods and outlines new clinical findings relating to knee osteoarthritis that were made possible by this approach.

New techniques were based on existing multivariate approaches, Partial Least Squares (PLS) and Non-negative Matrix Factorization (NMF) and validated using existing data sets.  The new techniques developed, PCA-PLS-LDA (Principal Component Analysis – Partial Least Squares – Linear Discriminant Analysis), PCA-PLS-MLR (Principal Component Analysis – Partial Least Squares –Multiple Linear Regression) and Waveform Similarity (based on NMF) were developed to address the challenging characteristics of biomechanical data, variability and correlation.  As a result, these new structure-seeking technique revealed new clinical findings.

The first new clinical finding relates to the relationship between pain, radiographic severity and mechanics.  Simultaneous analysis of pain and radiographic severity outcomes, a first in biomechanics, revealed that the knee adduction moment’s relationship to radiographic features is mediated by pain in subjects with moderate osteoarthritis.

The second clinical finding was quantifying the importance of neuromuscular patterns in brace effectiveness for patients with knee osteoarthritis.  I found that brace effectiveness was more related to the patient’s unbraced neuromuscular patterns than it was to mechanics, and that these neuromuscular patterns were more complicated than simply increased overall muscle activity, as previously thought.

abstract: PhD


title: Monitoring of Dynamic Bridge Behaviour Using Digital Image Correlation

contributor:
Hoult, Neil A.
Take, W. Andy
Civil Engineering

subject:
Civil Engineering
Digital Image Correlation
Dynamic
Displacement
Bridge Monioring

abstract: Thesis (Master, Civil Engineering) -- Queen's University, 2016-08-04 15:19:49.031

abstract:
Bridges are a critical part of North America’s transportation network that need to be assessed frequently to inform bridge management decision making. Visual inspections are usually implemented for this purpose, during which inspectors must observe and report any excess displacements or vibrations. Unfortunately, these visual inspections are subjective and often highly variable and so a monitoring technology that can provide quantitative measurements to supplement inspections is needed. Digital Image Correlation (DIC) is a novel monitoring technology that uses digital images to measure displacement fields without any contact with the bridge.
	In this research, DIC and accelerometers were used to investigate the dynamic response of a railway bridge reported to experience large lateral displacements. Displacements were estimated using accelerometer measurements and were compared to DIC measurements. It was shown that accelerometers can provide reasonable estimates of displacement for zero-mean lateral displacements. By comparing measurements in the girder and in the piers, it was shown that for the bridge monitored, the large lateral displacements originated in the steel casting bearings positioned above the piers, and not in the piers themselves.
	The use of DIC for evaluating the effectiveness of rehabilitation of the LaSalle Causeway lift bridge in Kingston, Ontario was also investigated. Vertical displacements were measured at midspan and at the lifting end of the bridge during a static test and under dynamic live loading. The bridge displacements were well within the operating limits, however a gap at the lifting end of the bridge was identified. Rehabilitation of the bridge was conducted and by comparing measurements before and after rehabilitation, it was shown that the gap was successfully closed.
	Finally, DIC was used to monitor the midspan vertical and lateral displacements in a monitoring campaign of five steel rail bridges. DIC was also used to evaluate the effectiveness of structural rehabilitation of the lateral bracing of a bridge. Simple finite element models are developed using DIC measurements of displacement. Several lessons learned throughout this monitoring campaign are discussed in the hope of aiding future researchers.

abstract: M.A.Sc.


title: Ablation of Steel by Microsecond Pulse Trains

subject: Steel Laser Microsecond Ablation

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2016-08-09 10:47:00.054

abstract:
Laser micromachining is an important material processing technique used in industry and medicine to produce parts with high precision. Control of the material removal process is imperative to obtain the desired part with minimal thermal damage to the surrounding material. Longer pulsed lasers, with pulse durations of milli- and microseconds, are used primarily for laser through-cutting and welding. In this work, a two-pulse sequence using microsecond pulse durations is demonstrated to achieve consistent material removal during percussion drilling when the delay between the pulses is properly defined. The light-matter interaction moves from a regime of surface morphology changes to melt and vapour ejection. Inline coherent imaging (ICI), a broadband, spatially-coherent imaging technique, is used to monitor the ablation process. The pulse parameter space is explored and the key regimes are determined.

Material removal is observed when the pulse delay is on the order of the pulse duration. ICI is also used to directly observe the ablation process. Melt dynamics are characterized by monitoring surface changes during and after laser processing at several positions in and around the interaction region. Ablation is enhanced when the melt has time to flow back into the hole before the interaction with the second pulse begins. A phenomenological model is developed to understand the relationship between material removal and pulse delay. Based on melt refilling the interaction region, described by logistic growth, and heat loss, described by exponential decay, the model is fit to several datasets. The fit parameters reflect the pulse energies and durations used in the ablation experiments. For pulse durations of 50 us with pulse energies of 7.32 mJ +/- 0.09 mJ, the logisitic growth component of the model reaches half maximum after 8.3 us +/- 1.1 us and the exponential decays with a rate of 64 us +/- 15 us. The phenomenological model offers an interpretation of the material removal process.

abstract: M.Sc.


title: The Elementary Teachers’ Perceptions of Motivation for and the Principal’s Influence on Their Engagement in Self-Directed Professional Development

contributor:
Kutsyuruba, Benjamin
Education

subject:
Culture
Motivation
Principal
Autonomy
Trust
Professional Development

abstract: Thesis (Master, Education) -- Queen's University, 2016-08-23 16:38:53.385

abstract:
All teachers participate in self-directed professional development (PD) at some point in their careers; however, the degree to which this participation takes place varies greatly from teacher to teacher and is influenced by the leadership of the school principal. The motivation behind why teachers choose to engage in PD is an important construct. Therefore, there is a need for better understanding of the leader’s role with respect to how and why teachers engage in self-directed professional development. The purpose of the research was to explore the elementary teachers’ motivation for and the school principal’s influence on their engagement in self-directed professional development.  Three research questions guided this study:
1.	What motivates teachers to engage in self-directed professional development?
2.	What are the conditions necessary for promoting teachers’ engagement in self-directed professional development?
3.	What are teachers’ perceptions of the principal’s role in supporting, fostering, encouraging, and sustaining the professional development of teachers?
A qualitative research approach was adopted for this study. Six elementary teachers from one south-eastern Ontario school board, consisting of three novice and three more experienced teachers, provided their responses to a consistent complement of 14 questions. Their responses were documented via individual interviews, transcribed verbatim, and thematically analysed.
The findings suggested that, coupled with the individual motivating influences, the culture of the school was found to be a conditional dynamic that either stimulated or dissuaded participation in self-directed PD. The school principal provided an additional catalyst or deterrence via relational disposition. When teachers felt their needs for competency, relatedness, and autonomy were satisfied, the conditions necessary to motivate teachers to engage in PD were fulfilled. A principal who personified the tenets of transformational leadership served to facilitate teachers’ inclinations to take on PD. A leadership style that was collaborative and trustful and allowed for personal autonomy was a dominant foundational piece that was critical for participant participation in self-directed PD. Finally, the principals were found to positively impact school climate by partaking in PD alongside teachers and ensuring there was a shared vision of the school so that teachers could tailor PD to parallel school interests.

abstract: M.Ed.


title: Characterization of the Galactic White Dwarf Population in the Next Generation Virgo Cluster Survey

subject: White Dwarf

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2016-08-06 17:50:33.421

abstract: Halo white dwarfs remain one of the least studied stellar populations in the Milky Way because of their faint luminosities. Recent work has uncovered a population of hot white dwarfs which are thought to be remnants of low-mass Population II stars. This thesis uses optical data from the Next Generation Virgo Cluster Survey (NGVS) and ultravoilet data from the GALEX Ultraviolet Virgo Cluster Survey (GUViCS) to select candidates which may belong to this population of recently formed halo white dwarfs. A colour selection was used to separate white dwarfs from QSOs and main-sequence stars. Photometric distances are calculated using model colour-absolute magnitude relations. Proper motions are calculated by using the difference in positions between objects from the Sloan Digital Sky Survey and the NGVS. The proper motions are combined with the calculated photometric distances to calculate tangential velocities, as well as approximate Galactic space velocities. White dwarf candidates are characterized as belonging to either the disk or the halo using a variety of methods, including calculated scale heights (z> 1 kpc), tangential velocities (vt >200 km/s), and their location in (V,U) space. The 20 halo white dwarf candidates which were selected using Galactic space velocities are analyzed, and their colours and temperatures suggest that these objects represent some of the youngest white dwarfs in the Galactic halo.

abstract: M.Sc.


title: Uptake of the Periodic Health Exam Among Adults With Intellectual and Developmental Disabilities From 2003 to 2015

contributor:
Ouellette-Kuntz, Hélène
Green, Michael
Community Health and Epidemiology

subject: Preventive Care

subject: Health Exam

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2016-08-08 18:54:05.415

abstract:
Background: Over the past decade, annual heath exams have been de-emphasized for the general population but emphasized for adults with intellectual and developmental disabilities (IDD).  The purpose of this project was to determine if there has been an increase in the uptake of the health exam among adults with IDD in Ontario, to what extent, and the effect on the quality of preventive care provided.
Methods: Using administrative health data, the proportion of adults (18-64 years old) with IDD who received a health exam (long appointment, general assessment, and “true” health exam), a high value on the primary care quality composite score (PCQS), and a health exam or high PCQS each year was compared to the proportion in a propensity score matched sample of the general population.  Negative binomial and segmented negative binomial regression controlling for age and sex were used to determine the relative risk of having a health exam/high PCQS/health exam or PCQS over time.
Results: Pre joinpoint, the long appointment and general assessment health exam definitions saw a decrease and the “true” health exam saw an increase in the likelihood of adults having a health exam.  Post joinpoint, all health exam definitions saw a decrease in the likelihood of adults having a health exam.  Pre joinpoint, all PCQS measures (high PCQS, long appointment or high PCQS, “true” health exam or high PCQS) saw an increase in the likelihood for adults to achieve a high PCQS or high PCQS/have a health exam.  Post joinpoint, all PCQS measures saw a decrease in the likelihood for adults to achieve a high PCQS or high PCQS/have a health exam.  Achieving a high PCQS was strongly associated with having a health exam regardless of health exam definition or IDD status.
Conclusions: Despite the publication of guidelines, only a small proportion of adults with IDD are receiving health exams.  This indicates that the publication of guidelines alone was not sufficient to change practice.  More targeted measures, such as the implementation of an IDD-specific health exam fee code, should be considered to increase the uptake of the health exam among adults with IDD.

abstract: M.Sc.


title: Academic Integrity and Senior Nursing Undergraduate Clinical Practice

contributor:
Sears, Kim
Nursing

subject:
Clinical Practice
Theory of Planned Behaviour
Nursing
Nursing Students
Academic Integrity

abstract: Thesis (Ph.D, Nursing) -- Queen's University, 2016-08-09 08:25:56.635

abstract:
Background:  Academic integrity (AI) has been defined as the commitment to the values of honesty, trust, fairness, respect, and responsibility with courage in all academic endeavours. The senior years of nursing studies provide an intersection for students to transition to professional roles through student clinical practice. It is essential to understand what predicts senior nursing students’ intention to behave with AI so that efforts can be directed to initiatives focused on strengthening their commitment to behaving with AI.
Research Questions: To what extent do students differ on Theory of Planned Behaviour (TPB) variables? What predicts intention to behave with academic integrity among senior nursing students in clinical practice across three different Canadian Schools of Nursing?
Method: The TPB framework, an elicitation (n=30) and two pilot studies (n=59, n=29) resulted

in the development of a 38 question (41-item) self-report survey (Miron Academic Integrity

Nursing Survey—MAINS: α>0.70) that was administered to Year 3 and 4 students (N=339).

Three predictor variables (attitude, subjective norm, perceived behavioural control) were

measured with students’ intention to behave with AI in clinical. Age, sex, year of study, program

stream, students’ understanding of AI policies, and locations where students accessed AI

information were also measured.

Results:  Hierarchical multiple regression analyses revealed that background, site, and TPB variables explained 32.6% of the variance in intention to behave with academic integrity. The TPB variables explained 26.8% of the variance in intention after controlling for background and site variables. In the final model, only the TPB predictor variables were statistically significant with Attitude having the highest beta value (beta=0.35, p<0.001), followed by Subjective Norm (beta=0.21, p<0.001) and Perceived Behavioural Control (beta=0.12, p<0.02).
Conclusion:  Student attitude is the strongest predictor to intention to behave with AI in clinical practice and efforts to positively influence students’ attitudes need to be a focus for schools, curricula, and clinical educators.  Opportunities for future research should include replicating the current study with students enrolled in other professional programs and intervention studies that examine the effectiveness of specific endeavours to promote AI in practice.

abstract: PhD


title: Design and Implementation of Tools for STM Studies in UHV and at the Solid-Liquid Interface

subject:
Liquid STM
Carbenes
STM

abstract: Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2016-08-09 20:29:46.184

abstract:
This thesis presents details of the design and development of novel tools and instruments for scanning tunneling microscopy (STM), and may be considered as a repository for several years' worth of development work. The author presents design goals and implementations for two microscopes. First, a novel Pan-type STM
was built that could be operated in an ambient environment as a liquid-phase STM.
Unique features of this microscope include a unibody frame, for increased microscope
rigidity, a novel slider component with large Z-range, a unique wiring scheme and
damping mechanism, and a removable liquid cell. The microscope exhibits a high
level of mechanical isolation at the tunnel junction, and operates excellently as an ambient tool. Experiments in liquid are on-going. Simultaneously, the author worked on designs for a novel low temperature, ultra-high vacuum (LT-UHV) instrument, and these are presented as well. A novel stick-slip vertical coarse approach motor was designed and built. To gauge the performance of the motor, an in situ motion sensing apparatus was implemented, which could measure the step size of the motor to high precision. A new driving circuit for stick-slip inertial motors is also presented, that o ffers improved performance over our previous driving circuit, at a fraction of
the cost. The circuit was shown to increase step size performance by 25%. Finally, a horizontal sample stage was implemented in this microscope. The build of this UHV instrument is currently being fi nalized. In conjunction with the above design projects, the author was involved in a collaborative project characterizing N-heterocyclic carbene (NHC) self-assembled monolayers (SAMs) on Au(111) films. STM was used to characterize Au substrate quality, for both commercial substrates and those manufactured via a unique atomic layer deposition (ALD) process by collaborators. Ambient and UHV STM was then also used to characterize the NHC/Au(111) films themselves, and several key properties of these films are discussed. During this study, the author discovered an unexpected surface contaminant, and details of this are also presented. Finally, two models are presented for the nature of the NHC-Au(111) surface interaction based on the observed film properties, and some preliminary theoretical work by collaborators is presented.

abstract: There is a possibility that a Patent may be filed for a design described in the Thesis. For this reason, we request the Thesis be restricted until further notice.

abstract: M.Sc.


title: Beyond Black and White: The grisaille exterior of the Netherlandish triptych

contributor:
Spronk, Ron
Art History

subject:
Early Netherlandish Painting
Art History

abstract: Thesis (Ph.D, Art History) -- Queen's University, 2016-08-09 20:56:39.218

abstract:
This thesis is a study of fifteenth- to mid sixteenth-century Netherlandish triptych exteriors, focusing on the so-called ‘grisaille’ technique. During this period, altarpieces produced in the Low Countries were typically constructed in a tripartite format with folding wings. This arrangement created the opportunity for pictorial representations on both sides of the hinged panels. Painters emphasized the distinction between the triptych’s two faces by executing the exteriors in a strikingly more subdued palette than the interiors. Particular iconographic subject matter was favoured for grisailles, which often depict the Annunciation or saints that reflect the triptych’s patronage or intended location.  Jan van Eyck was notable for his emphasis on imitating stone statuary and created three important grisailles, one of which would influence triptych exteriors for years to come. Hieronymus Bosch, an artist working at the turn of the sixteenth century, also brought innovation to his grisailles, further expanding the potential of these reduced-palette paintings. This thesis examines the creative process involved in the production of grisailles and compares the underdrawings of triptych exteriors to those of the corresponding polychromatic interiors. In this study, grisailles are situated in their context as part of multifaceted artworks as well as within the broader church environment.

New infrared reflectograms were generated using Queen’s OSIRIS infrared camera to document works in Belgium and the Netherlands. While some aspects of underdrawings could indicate that the figure was meant to imitate statuary, this distinction was not directly linked to triptych exteriors and was related instead to efforts at a trompe-l’oeil effect. Such attempts at mimicry can also be found on triptych interiors. Through a close examination of the underdrawing stage of these paintings it appears that this part of the creative process was not distinguished in any significant way from the underdrawings of triptych interiors.

abstract: This thesis is to be restricted because I plan to publish parts of my doctoral research in article form in the coming five years.

abstract: PhD


title: Understanding arsenic mobility and speciation in lake sediments impacted by ore roasting near Giant mine, NWT

contributor: Geological Sciences and Geological Engineering

subject:
Arsenic speciation
Roaster-impacted lakes
Giant mine
Arsenic mobility

abstract: Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2016-08-10 13:57:02.337

abstract:
The roasting of gold-bearing arsenopyrite at Giant mine (Northwest Territories) between 1949 and 1999 released approximately 20,000 tonnes of toxic arsenic-bearing aerosols in the local aerial environment. Detailed examination of lake sediments, sediment porewaters, surface waters and lake hydrology sampled from three lakes of differing limnological characteristics was conducted in summer and winter conditions. Samples were analyzed for solid and dissolved elemental concentrations, speciation and mineralogy. The three lakes are located less than 5km from the mine roaster, and downwind, based on predominant wind direction. The objective of the study was to assess the controls on the mobility and fate of arsenic in these roaster-impacted subarctic lacustrine environments.
Results show that the occurrence of arsenic trioxide in lake sediments coincides with the regional onset of industrial activities. The bulk of arsenic in sediments is contained in the form of secondary sulphide precipitates, with iron oxides hosting a minimal amount of arsenic near the surface-water interface. The presence of geogenic arsenic is likely contained as dilute impurities in common rock-forming minerals, and is not believed to be a significant source of arsenic to sediments, porewaters or lake waters. Furthermore, the well correlated depth-profiles of arsenic, antimony and gold in sediments may help reveal roaster impact.
The soluble arsenic trioxide particles contained in sediments act as the primary source of arsenic into porewaters. Dissolved arsenic in reducing porewaters both precipitate as secondary sulphides in situ, and diffuse upwards into the overlying lake waters. Arsenic diffusion out of porewaters, combined with watercourse-driven residence time, are estimated to be the predominant mechanisms controlling arsenic concentrations in overlying lake waters. The sequestration of arsenic from porewaters as sulphide precipitates, in the study lakes, is not an effective process in keeping lake-water arsenic concentrations below guidelines for the protection of the freshwater environment and drinking water.
Seasonal impacts on lake geochemistry derive from ice covering lake waters, cutting them off from of atmospheric oxygen, along with the exclusion of solutes from the ice. Such effects are limited in deep lakes but are can be an important factor controlling arsenic precipitation and mobility in ponds.

abstract: M.A.Sc.


title: The differential impact of oxytocin receptor (OXTR) genotypes on the risk of autism spectrum disorder (ASD) and resulting social communication deficits

contributor:
Ouellette-Kuntz, Hélène
Liu, Xudong
Community Health and Epidemiology

subject:
ADI-R
single nucleotide polymorphisms
oxytocin
social communication
sibling-pairs
autism spectrum disorder

abstract: Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2016-08-11 19:52:25.759

abstract:
Background: Autism spectrum disorder (ASD) is multifactorial and is likely the result of complex interactions between multiple environmental and genetic factors. Recently, it has been suggested that each symptom cluster of the disorder, such as poor social communication, may be mediated by different genetic influences. Genes in the oxytocin pathway, which mediates social behaviours in humans, have been studied with single nucleotide polymorphisms (SNPs) in the oxytocin receptor gene (OXTR) being implicated in ASD. This thesis examines the presence of different oxytocin receptor genotypes, and their associations with ASD and resulting social communication deficits.
Methods: The relationship between four OXTR variants and ASD was evaluated in 607 ASD simplex (SPX) families. Cases were compared to their unaffected siblings using a conditional logistic approach. Odds ratios and associated 95 percent confidence intervals were obtained. A second sample of 235 individuals with a diagnosis of ASD was examined to evaluate whether these four OXTR variants were associated with social communication scores on the Autism Diagnostic Interview – Revised (ADI-R). Parameter estimates and associated 95 percent confidence intervals were generated using a linear regression approach. Multiple testing issues were addressed using false discovery adjustments.
Results: The rs53576 AG genotype was significantly associated with a lower risk of ASD (OR = 0.707, 95% CI: 0.512-0.975). A single genotype (AG) provided by the rs2254298 marker was found to be significantly associated with higher social communication scores (Parameter estimate = 1.833, SE = 0.762, p = 0.0171). This association was also seen in a Caucasian only and mothers as the respondent samples. No association was significant following false discovery rate adjustments.
Conclusion: The findings from these studies provide limited support for the role of OXTR SNPs in ASD, especially in social communication skills. The clinical significance of these associations remains unknown, however, it is likely that these associations do not play a role in the severity of symptoms associated with ASD. Rather, they may be important in the appearance of social deficits due to the rs2254298 markers association with enlarged amygdalas.

abstract: M.Sc.