title: STUDYING THE OVERHEAD AND CROWD-SOURCED RISK ASSESSMENT STRATEGY OF DEPENDENCY MANAGEMENT BOTS

contributor:
Hassan, Ahmed
Computing

subject:
Bots
Dependency Management
Software Engineering
Mining Software Repositories

abstract:
As today's software systems are increasingly built with dependency relationships, where a client package makes use of a specific version of a provider package, these client packages must effectively manage their dependencies. To help facilitate this dependency management process, clients are increasingly adopting dependency management bots to alert them when a provider package they depend on releases a new version and whether the new version of said provider package is compatible with their package.

Integrating these dependency management bots into a project requires a certain level of effort on the part of the client, and once the bot begins performing its specific function, human intervention is usually required to either accept or reject any action or recommendation the bot generates. This creates additional, and sometimes unnecessary, work for clients, which can deter them from continuing to use the bot.
Additionally, dependency management bots have begun to implement the promising strategy of leveraging "the crowd" to help clients assess the involved risks with accepting a dependency update. This opportunity to use knowledge from "the crowd" to aid client packages with dependency management is interesting and unique to dependency management bots, as they have access to the vast store of data representing how compatible each provider package release is across many client packages. In this thesis, we present two studies that examine these attributes of dependency management bots. First, we describe a large empirical study on the overhead that is introduced in client packages that adopt dependency management bots. In particular, we provide a series of practical recommendations to help designers of dependency management bots reduce the amount of unnecessary work they create in client packages. Next, we describe a large scale study on the efficacy of dependency management bots leveraging "the crowd" to provide supporting metrics to help clients assess the risk of accepting a dependency update. Our findings will help designers of dependency management bots effectively leverage crowd-sourced data to aid client packages with dependency management.

abstract: M.Sc.


title: Investigating the role of Ricinus communis Ca2+-dependent protein kinase-1 (RcCDPK1) autophosphorylation and the regulatory networks of RcCDPK1 and its Arabidopsis ortholog AtCPK4

contributor:
Plaxton, William
Snedden, Wayne
Biology

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:
Biology
Biochemistry
Kinase
Phosphorylation
Autophosphorylation
Molecular Genetics
RcCDPK1
AtCPK4
Arabidopsis thaliana
Ricinus communis
Metabolism
Plant Biology
Kinetics
Protein

abstract: Castor (Ricinus communis) oil seeds (COS) have become an important model for studies of oil seed metabolism owing to their unusually high accumulation of storage triacylglycerides. R. communis Ca2+-dependent protein kinase-1 (RcCDPK1) catalyzes in vivo inhibitory phosphorylation of bacterial-type phosphoenolpyruvate carboxylase (PEPC) at Ser451 in developing COS. Bacterial-type PEPC (BTPC) functions as a regulatory and catalytic subunit of an unusual, mitochondrial surface-associated Class-2 PEPC complex, hypothesized to play crucial roles in controlling anaplerotic photosynthate partitioning to storage oils while recycling respiratory CO2 in developing COS. This thesis aimed to address how autophosphorylation influences RcCDPK1’s transphosphorylation of BTPC at Ser451, as well as to expand the kinase’s regulatory networks in conjunction with its close Arabidopsis ortholog AtCPK4. LC-MS/MS of fully autophosphorylated RcCDPK1 detected 42 phosphorylated Ser, Thr, or Tyr residues. Prior autophosphorylation markedly attenuated the ability of RcCDPK1 to transphosphorylate its BTPC substrate at Ser451. Tyr30 was identified as an autophosphorylation site of particular interest as it occurs at the junction of RcCDPK1’s N-terminal variable and catalytic domains and is widely conserved in plant and protist CDPKs. Analysis of a RcCDPK1Y30F mutant indicated that Tyr30 autophosphorylation primes RcCDPK1 for transphosphorylating BTPC at Ser451. To expand RcCDPK1’s and AtCPK4’s known regulatory networks a combination of biochemical and functional genetic approaches were integrated. RcCDPK1 and AtCPK4 effectively phosphorylated Arabidopsis abscisic acid (ABA) transcription factor-4 (AtABF4) and its closest castor ortholog, RcTRAB1. LC-MS/MS revealed several conserved AtABF4 and RcTRAB1 Ser or Thr residues were targeted by both CDPK orthologs. A medium-throughput screen known as a Kinase-Client (KiC) assay was also used to identify additional RcCDPK1/AtCPK4 substrates. These included Ras-group-related leucine-rich repeat protein-9 (AtPIRL9), as well as the E3-ubiquitin ligase AtATL6. The overall results of this thesis link RcCDPK1/AtCPK4 to novel regulatory pathways involved in ABA and immune signaling, and carbon/nitrogen interactions, while creating interesting testable hypotheses for future research. Collectively, this project uncovered novel aspects of RcCDPK1 and AtCPK4 regulation that shed light on autophosphorylation in CDPKs, as well as identifying putative conserved substrates that may be regulated by these critical kinases.

abstract: PhD


title: Organic Growth: Sustainable Settlement Planning for Displaced Populations in Developing Countries

contributor:
Mabee, Warren, supervisor
DeLoyde, Carolyn, supervisor
Geography and Planning Department

rights: Attribution-NonCommercial-ShareAlike 3.0 United States

subject:
Displacement
Refugees
Settlements
Refugee Camp
Climate Change
United Nations
Sustainable Development
Settlement Planning
Shelter Design
Sustainable Development Goals
Sustainable Planning
Environmental Impact Assessment
Emergency Response
Environmental Planning
Erbil
Internal Displacement
Internally displaced person
Iraq refugee camp
Vernacular Architecture
Participatory Planning
UNHCR
Forced Migration
Kawergosk Refugee Camp

abstract: Human displacement and climate change are two of the most critical global crises in the contemporary world, and they are highly interdependent. In order to mitigate the impact of temporary refugee camps or prolonged displacement settlements on the surrounding environment and the people housed within, a constructive planning approach should be adopted to advance sustainable settlement planning in accordance with the UN Sustainable Development Goals (SDG). The objective of this research is to identify planning and design principles that will guide the establishment of vibrant, dynamic communities that will positively contribute to the host country and urban context. The planning principles discussed and explored in this study are framed around the targets of SDG15 – life on land, SDG11 – sustainable cities and communities, and SDG7 – affordable and clean energy. Gaps in current approaches to displacement settlement developments are investigated, followed by evaluation of policies mandated by the United Nations and affiliated organizations. The three SDGs studied are discussed to expand upon the intent of each goal, and various practices adopted in order to achieve specified targets. A case study of an existing settlement at Kawergosk Refugee Camp is examined.  The evolution of this settlement is tracked over three distinct phases, while the proposed approach to improve the site may be viewed as a 4th phase of development. Planning practices discussed in this thesis include the execution of a modified Environmental Impact Assessment, engaging in participatory planning and design at the human scale, and utilizing vernacular design to address a particular place at a specific moment in time by conducting site analysis and evaluating the existing context. Identifying environmental resources at the site level facilitates the use of vernacular design to reduce energy consumption and incorporation of appropriate technologies for renewable energy generation. Finally, implementing participatory planning and community engagement in achieving these processes promotes sustainable growth, progress, and maintenance of a settlement or refugee camp for displaced persons.

abstract: M.PL.


title: Academic Procrastination and Achievement Motivation: An Expectancy Value Approach to Measure Academic Procrastination in University Online Courses

contributor:
Matheson, Ian
Education

subject:
education
online learning
higher education
procrastination
motivation

abstract:
The purpose of this study was to investigate the relationship between students’ achievement motivation and their procrastination behaviour when learning online. Student achievement motivation was measured using Eccles and Wigfield’s (2020) Situated Expectancy Value Theory (SEVT), which conceptually understands a student’s achievement related choices and performance on a task, as influenced by the student’s valuation of that task, and their expectancy to succeed in completing that task. Within this theory, a student’s choices and performance on an academic task, are predicted by several dimensions of value such as interest, utility, cost, and attainment, as well as their expectancy to succeed at the task.

A total of 171 students enrolled in online courses at a mid-sized Canadian university participated (29 male, 135 females, 5 other). Participants completed a 101-item questionnaire consisting of demographic questions, procrastination measures, and SEVT measures. Regression analysis indicated that values and expectancies were different across all three learning activities, but self-efficacy for time management was consistently the strongest predictor of procrastination. Further, trait procrastination as a predictor in the model, overpowered task values and decreased the strength of the self-efficacy measures. The results indicated that efficacy for time management and trait procrastination behaviour were the two strongest predictors of procrastination, indicating that time management strategies and personal tendency to procrastinate, best predict procrastination behaviour.

abstract: M.Ed.


title: Edge Computing and Machine Learning in Machinery Condition Monitoring

rights: Attribution-NonCommercial-NoDerivs 3.0 United States

subject:
Machine Condition Monitoring
Machine Learning
Edge Computing

abstract:
Reactive maintenance in industry is associated with high downtime costs and the risk of catastrophic failure; predictive maintenance has the potential to mitigate these costs and risks. Currently, to analyze tool wear in CNC machines, rolling element bearing health, and other vibration-sensitive environments, accelerometers are used to gather vibration data. It is common in industry to use feature extraction (i.e., Fourier Transform) to identify fault frequencies in the vibration signals. Machine learning can also be used to identify patterns in the faulty equipment’s vibrations. Machine learning can provide accurate predictions on bearing and tool health from raw vibration data given enough data, training time, and computational power. However, connection to powerful computational resources (the cloud) is not always possible in remote locations or for security reasons. In many applications, it would be useful to leverage the power of machine learning in a local device. This practice is called edge computing, and its feasibility is investigated in this research.
A small device is used to demonstrate a low-cost, easy to install solution. Data preprocessing, model training, and data analysis are all possible on a small local device. However, it is possible to save time and computational power by training the model elsewhere and simply using it for inference (to make predictions) on the small device.
The prediction accuracy and time to compute of eight machine learning models was compared between a high-end CPU and a small device CPU over four data sets (two bearing health and two tool wear). From all the models, a convolutional neural network was shown to be optimal using compute time and accuracy as metrics. The small device CPU was able to make predictions in only 15 times the amount of time as the high-end CPU. In this way, the tests verified the feasibility of using an edge computing device with machine learning for machine condition monitoring.

abstract: M.A.Sc.


title: The Effect of Vaginal Estrogen on Circulating Estrogen and Breast Cancer Risk in Postmenopausal Women Participating in the MAP.3 Breast Cancer Prevention Trial

contributor:
Richardson, Harriet
Public Health Sciences

subject:
Vaginal Estrogen
Serum estrogen
Breast cancer

abstract:
Background: Vaginal estrogen (VE) is the current gold standard treatment for managing genitourinary syndrome of menopause (GSM) symptoms caused by low estrogen levels in postmenopausal women. However, a research gap exists regarding the potential risks with long-term use and safety in women receiving aromatase inhibitor (AI) therapy for breast cancer prevention or treatment. This thesis examined the effect of VE use on serum estrogen concentrations in postmenopausal women participating in the Mammary Prevention.3 (MAP.3) trial. The association between elevated estrogen, VE use and breast cancer risk was also examined in exploratory analyses.
Methods: Estrone (E1) and estradiol (E2) were quantified with LC-MS/MS from blood collected from MAP.3 participants at baseline (n=4,111) and one-year post-randomization (placebo (n=1,682) or exemestane (n=1,544)). VE use was self-reported and annual mammograms recorded breast cancer events. Multiple linear regression modeling was conducted to investigate the association between VE use and serum estrogen at baseline and recent VE use at year-1, in the placebo arm only. Log-binomial regression assessed the association between VE use and estrogen in women on exemestane at year-1. Logistic regression was used to explore the association between estrogen levels that were at or above a pre-specified threshold and breast cancer risk in the exemestane arm, and VE use at baseline and subsequent risk of breast cancer up to year-5 in MAP.3 participants, with treatment as an interaction term.
Results: VE use had a statistically significant association with circulating E1 and/or E2 concentrations, regardless of duration of use and treatment arm (placebo or exemestane), in multivariable models. No statistically significant association was observed between estrogen levels at or above the pre-specified threshold and breast cancer risk (OR=1.60; 95% CI, 0.25-8.31, p=0.76) nor with VE use and breast cancer risk, although effect estimates were elevated in the stratified and pooled treatment arms (ORpooled=1.45; 95% CI, 0.62-3.43).
Conclusions: VE use appears to elevate serum estrogen levels in postmenopausal women, even when concurrently on exemestane. However, the clinical relevance of this finding needs further evaluation, in larger studies, given the non-significant association with estrogen levels at or above the threshold or VE use and breast cancer risk.

abstract: M.Sc.


title: A Peripartum Assessment of Nailfold Capillary Density in Women With Preeclampsia

contributor:
Smith, Graeme
Biomedical and Molecular Sciences

subject:
Preeclampsia
Nailfold Video Capillaroscopy

abstract: Preeclampsia (PE) is characterized as new-onset hypertension in pregnancy (>140mmHg systolic or >90mmHg diastolic), along with proteinuria and is a leading cause of maternal mortality and morbidity worldwide. Despite the etiology of PE remaining elusive, it is thought that placental trophoblast cells do not adequately invade into the inner myometrium layer of the uterus during placentation, resulting in the incomplete remodelling of the uterine spiral arteries. As a result, the placenta becomes hypoperfused and releases pathogenic factors in response. Pathogenic factors, such as reactive oxygen species (ROS) and soluble fms-like tyrosine kinase one (sFlt-1), cause systemic endothelial dysfunction, ultimately leading to hypertension and accompanying symptoms of PE. While symptoms typically resolve after delivery, those with a history of PE are at an increased risk of developing cardiovascular disease (CVD) later in life. Despite this, many individuals with a history of PE in pregnancy are not offered cardiovascular risk surveillance or intervention to prevent CVD postpartum. Since CVD and increased risk of CVD have both been associated with declined nailfold capillary density, nailfold video capillaroscopy (NVC) could be used as a postpartum assessment tool to identify those at increased risk of CVD. The objective of the current study was to determine if the nailfold capillary density (capillaries/mm2) of women with PE is reduced when compared to controls both antepartum and postpartum. Previous literature supports our hypothesis that nailfold capillary density will be reduced in preeclamptic participants when compared to controls and that this decline in density will persist postpartum. The nailfold capillaries of 32 control and 15 preeclamptic participants were assessed using NVC within 2 weeks antepartum and 48-hours postpartum. No difference in the average nailfold capillary densities was found between groups before or after delivery. Prior evidence of structural and functional changes to the microvasculature after a pregnancy complicated by PE suggests that further investigation to clarify these results is necessary. Further awareness of the lasting impacts of PE on the microvasculature may provide support for the surveillance of PE patients postpartum and to mitigate their increased risk of CVD later in life with pharmaceutical and lifestyle interventions.

abstract: M.Sc.


title: Friends and Friendships: Exploring the Views of School-aged Children with Disabilities

contributor:
Batorowicz, Beata
Rehabilitation Science

subject: friends

subject: friendships

subject: children with disabilities

abstract:
Background: Friends and friendships are critical to well-being, and they typically develop during childhood. Children with disabilities, particularly those with physical and communication disabilities, have limited interactions with peers, which may impact their friendships. Research on views of children with disabilities about their friendships is scarce, and the scope of research evidence in this area is unknown.

Purpose: This thesis sought to explore how school-age children with disabilities describe and characterise their friends and friendships with peers. Special attention was given to children with motor and communication disabilities, as they have been reported to have profoundly limited social networks.

Methods: I conducted two inter-related studies, starting with the scoping review to identify key characteristics and quality of friendships of children with disabilities (aged 5–15), according to them. Subsequently, I conducted an exploratory descriptive qualitative study with children with motor and communication impairments who used augmentative and alternative communication (AAC).

Results: The 51 studies found in the review reported views of children mostly with intellectual and/or developmental disabilities. The majority of children described friendships as companionship and helping and supporting each other and they met with friends mainly at school. The children had lower friendships qualities than their peers without disabilities and reported experiences of enjoyment and belonging as well as rejection and exclusion. In Study 2, children who used AAC characterised friendships similarly -by spending time together in activities and showing fondness towards each other. Children without disabilities talked about joint activities; however, they also talked about trust and loyalty and reported a wider range of indoor and outdoor activities.

Conclusions: This thesis found that 5–15 years old children with disabilities, including those who used AAC, described friendships in relation to spending time together and engaging in activities with peers. Yet, the findings also highlighted restricted social contexts and activity settings experienced by children, which suggests limited opportunities to spend time together and develop meaningful relationships over time. Future research should aim to better understand the friendships of children with disabilities at different ages as well as conditions supporting and inhibiting joint participation.

abstract: M.Sc.


title: Spatiotemporal Analysis on Distributed Task Offloading in Extreme Edge Devices

contributor:
Sorour, Sameh
ElSawy, Hesham
Hassanein, Hossam
Computing

subject:
Extreme Edge Devices
Stochastic Geometry
Markov Chains
Spatiotemporal Analysis
Average Response Delay

abstract: With the rapid development of the Internet of Things (IoT), the number of smart devices connected to the Internet is exponentially increasing, resulting in large-scale data and inadequate resources, which has caused high congestion and slow response delay in legacy cloud computing models. Multi-access Edge Computing (MEC) is a computing paradigm that can facilitate both delay-sensitive, and data-intensive tasks associated with IoT applications. MEC provides low latency by pushing the resources closer to the applications. However, due to the increase in the number of devices that use MEC, the high congestion problem remains unsolved. A promising solution is to take advantage of the abundant and underutilized computing resources of the Extreme Edge Devices (EEDs). EEDs bring the computing service closer to the end-users, which could significantly reduce the delay caused by cloud execution. However, the success of such an extreme edge parallel computing paradigm is impacted by i) wireless device-to-device (D2D)communication performance, a requirement for the communication between the recruited EEDs and the task requester to perform the offloading process, ii) the computing capabilities of the EEDs, which governs the execution time of each offloaded task and iii) the reliability of the recruited EEDs. In this context, a novel spatiotemporal framework employing stochastic geometry and absorbing continuous time Markov chains (ACTMC) is developed to analyze the communication and computation performance of extreme edge computing systems. Using this framework, we study the influence of various system parameters on the average task response delay over a baseline system, where the devices are recruited randomly and do not fail during the execution. Extensive evaluations have shown that the EED-enabled system outperforms MEC in terms of the average response delay in some cases. Next, we developed an advanced model, where the possibility of failure of the recruited EEDs is considered, and the impact of the recruitment criteria of EEDs on the recruitment time is investigated. Our findings have revealed the optimal number of slices that the task should be divided into to minimize the total computation time, which will minimize the average response delay, and how that optimal number is affected by the various system parameters.

abstract: M.Sc.


title: Adaptive Feedback Control of Generalized Hamiltonian Systems With Unstructured Components

contributor:
Hudon, Nicolas
Chemical Engineering

subject:
Adaptive control
Feedback control
Hamiltonian systems
Stability

abstract: This dissertation considers the problem of feedback controller design for systems represented in non-exact generalized Hamiltonian form. The generalized Hamiltonian representation of dynamical systems has some properties that facilitate stability and controller design for nonlinear control systems. Despite extensive studies on generalized or port-Hamiltonian controlled systems, application to chemical engineering processes is limited as mass and energy balances are difficult to re-write exactly in potential-driven forms. We represent dynamics as a combination of a structured generalized Hamiltonian component and an unstructured component. We explore the stability of the unforced system after introducing the non-exact generalized Hamiltonian form and show that the non-exact generalized Hamiltonian system is stable in open-loop given mild assumptions on the unstructured component. Then, we exploit the properties of the structured part of the dynamic to design a state and observer-based feedback controller to stabilize the system at a desired set-point. In the next stage, we demonstrate the robustness of the proposed algorithms by modifying the obtained controller so that it can handle uncertain parameters and ensure stability even if exact parameter estimation is not available. In the last phase of the research, we aim to develop adaptive state and observer-based stabilizing feedback controllers guaranteeing exact parameter estimation. Different cases and applications are discussed.

abstract: PhD


title: A History of Debates Over Trans Women’s Inclusion in Elite Sport and Trans Athlete Activism in Canada

contributor:
Adams, Mary Louise
Kinesiology and Health Studies

subject: trans inclusion in sport

subject: trans athlete activism

subject: trans athletes

subject: trans women athletes in sport

subject: trans athletes and human rights

subject: trans activism in Canada

subject: transphobia in sport

subject: transfeminism

subject: history of debates over trans inclusion in sport

subject: trans studies

subject: transfeminist methodologies

subject: trans agency in sport

subject: trans resistance in sport

abstract: Since Renée Richards became the first known trans woman to compete in a sport event (tennis) in 1976, trans women’s inclusion has been a contentious issue in sport. This dissertation project pieces together a (not the) history of debates over trans women’s inclusion in sport, with a focus on the activism of trans athletes in Canada. The project has been influenced by Foucault’s archeological and genealogical forms of historical analysis, transfeminist theories, and trans studies scholarship. As evidence, I draw on a wide range of primary sources, produced between 1976 and 2022, related to trans athletes in sport including print and online English Canadian newspaper and magazine articles, autobiographies, blog posts, documentaries, interviews, podcasts, written court decisions, and policies, guidelines from sport organizations. This research demonstrates that arguments against the inclusion of trans women athletes are shaped by sexist, transmisogynist, and racist myths and by discourses through which understandings of sex, gender, transness are created. In particular, I focus on scientific and popular discourses about testosterone and athletic performance. Grounded by transfeminist theories and methodologies, this dissertation aims to shift the themes of analysis and the interpretations of trans inclusion in the sport studies literature. My analysis does not centre on trans women’s embodiment or forms of gender expression. Trans women athletes do not appear in this study as tropes who reinforce female inferiority or the gender binary in sport or elsewhere. I argue that trans athletes have been active agents of resistance and change, confronting their critics, engaging in activism, and producing discursive (e.g., policies, guidelines) and material (e.g., access to fields, rinks, tracks, coaches, equipment) changes for trans people in sport. Their resistance and activism have been key to making possible the increasingly trans inclusive and gender expansive sporting environments that we see today in Canada.

abstract: PhD


title: Living Undocumented in Canada

contributor:
Aiken, Sharry
Cultural Studies

subject:
Illegalized immigrants
Undocumented
Narrative
Testimonio
Non-status immigrants
Trauma
Resilience

abstract:
Illegalized immigrants in Canada are a growing community, yet narratives about their lives are rarely in the public eye. Discourses on the importance of safeguarding national security have shaped how vulnerable immigrants are perceived as undesirable and criminals. Such perceptions have contributed to increased border controls. These controls have resulted in the intensification of detention and deportation regimes across the globe. Immigration policies and practices have also been transformed leading to the creation of precarious conditions for migrants. At the same time, economic recession, environmental degradation, national internal conflict, erosion of social safety nets, and criminal violence continue to produce local social and economic conditions that force people to leave the Global South to venture out in search of dignity and wellbeing. Many of these migrants have come to Canada with precarious immigration status. In Living Undocumented in Canada, four women and four men who are illegalized and have lived underground for many years tell their testimonios. This project investigates and visibilizes the lives and knowledge production of eight illegalized immigrants who live under the threat of deportation.

Living Undocumented in Canada is a project consisting of a book of narratives, and three other chapters that are part of the analytical section of this project. The first chapter, as the introduction to the entire project, discusses the global and Canadian context that produces illegality, as well as the methodology used for this project. The inland refugee determination process is particularly discussed in this section. The second chapter discusses testimonio as method that gives voice to the experiences of illegalized immigrants. I argue that these experiences embody a counter-narrative in opposition to prevailing rhetoric that illegalizes immigrants. In the third chapter, the psychological impact of living under the threat of deportation as experienced by illegalized people is explored. The stories of illegalized people disclose a particular type of trauma that resonates with the experiences of trauma of those living under conditions of war. This type of trauma is known as continuous trauma stress because of the continuing nature of threat to their lives. Despite that, the narrators exercise their agency and bravery to stay as people who bear rights, despite the absence of legal channels that validate their claim to stay.

abstract: PhD


title: Paper Recycling at Queen’s University and its Waste Implications

subject:
Life Cycle Assessment
Paper Recycling
Circular Economy

abstract: The procurement and disposal of paper commodities presents a unique case in respect to municipal solid waste at Queen’s University at Kingston, ON. Using Queen’s University Admissions viewbook & Queen’s Alumni Review magazine as a case study, this thesis investigates how the procurement, distribution, and disposal of these paper commodities can be altered to better align with the Resource Productivity & Recovery Authority’s, Ontario Regulation 391/21, made under the Resource Recovery & Circular Economy Act, 2016. The aim of this project was to investigate whether printing volumes of these products were altered upon the onset of Covid-19, and how the lifecycle of these publications creates environmental implications. Using primary and secondary research, I concluded that a complex pathway exists in the end-of-life management of these products, due to their composition, and thus, compatibility with Kingston, ON, recycling programs. As such, alternatives to these documents including an online format present a more sustainable medium-- should these commodities continue to be produced. However, a purely digital delivery of these documents also displays environmental concerns, preventing Queen’s University from reaching its highest potential to align with the Resource Productivity & Recovery Authority’s legislation related to individual producer responsibility (IPR).


title: Enantioselective Borylation of Benzhydryl Triflones

contributor:
Crudden, Cathleen
Chemistry

subject:
Transition-Metal Catalysis
Asymmetric Catalysis
Boronic Ester

abstract: Aryl boronic esters are useful building blocks in organic chemistry. Their carbon-boron bond can be easily converted into carbon-carbon bonds, using Suzuki-Miyaura cross coupling reactions, or into various carbon-heteroatom bonds. There are several well-established methods for synthesizing boronic esters. Some of them require hardly accessible starting materials or enable only limited access to different substrates. Hence, we investigate in this thesis the synthesis of enantioenriched boronic esters from benzhydryl triflones, which are easily accessible, underutilized starting materials. Chiral boronic esters are of particular interest due to their unique properties and functionalization options. Herein we report the development of a palladium catalyst with chiral N-heterocyclic carbene ligands, which enables the synthesis of chiral boronic esters with good stereoselectivity.

abstract: M.Sc.


title: The Influence of Perceived Control and Helplessness on Chronic Pain

subject:
Chronic pain
Helplessness
Perceived control

abstract: The present dissertation includes three empirical studies (Chapters 2-4) examining the relationships between perceived control constructs and chronic pain related outcomes. Study One (Chapter 2) examined whether low self-efficacy and heightened perceived stress were associated with dyspareunia at two timepoints during the COVID-19 pandemic among sixty-two participants (31 with and 31 without dyspareunia) who completed a longitudinal online survey. This survey demonstrated that during the COVID-19 pandemic, individuals with dyspareunia experienced more stress and less general-self-efficacy across the time points. In addition, this study did not find that decreases in perceived stress were associated with decreases in sexual distress, suggesting other factors may be contributing to, and maintaining, sexual distress. Study Two (Chapter 3) aimed to further our understanding of pain characteristics and the role of control cognitions and sexual flexibility in those with anodyspareunia (recurrent or persistent anal pain during receptive anal penetration) in an online survey. Results indicated that as participants reported more cognitions related to a loss of control, pain symptoms and sexual distress worsened, as predicted. Although flexibility did not significantly moderate the relationships between control cognitions and pain or distress, greater sexual flexibility was significantly associated with less sexual distress. In a sample of 350 individuals on MTurk with chronic pain, the Chronic Disease Helplessness Scale (CDHS), a measure of the motivational/motor, cognitive, and emotional deficits that have been previously observed to occur in people who experience learned helplessness, was developed and validated (Study Three, Chapter 4). The CDHS total score was significantly associated with greater pain intensity and interference, lower perceived pain control, and lower general self-efficacy. Individuals with diabetes displayed significantly lower CDHS scores compared to individuals with chronic pain, demonstrating discriminant validity. The results of these studies have yielded a psychometrically sound and conceptually valid measure of helplessness for future assessments of control constructs and further illuminated the influence of control constructs that may uniquely influence individuals who live with pain.

abstract: PhD


title: Clinical Utility and Impact of Targeted Nucleic Acid Sequencing in Myeloid Malignancies and Precursor Lesions

contributor:
Rauh, Michael
Pathology and Molecular Medicine

subject:
NGS
Myeloid Malignancy
Clinical Utility

abstract: Recent technological advances have permitted the identification of several genes recurrently mutated in myeloid malignancies, including myelodysplastic syndromes (MDS), myeloproliferative neoplasms (MPN) and acute myeloid leukemia (AML), with expanding diagnostic and clinical significance. Given the breadth of genetic aberrations required to diagnose these diseases, higher throughput testing is necessary. Targeted next-generation sequencing (NGS) panels offer promise in detecting these molecular features. Furthermore, several myeloid precursor lesions, such as clonal hematopoiesis of indeterminate potential (CHIP) and clonal cytopenias of undetermined significance (CCUS), have been linked to the development of myeloid malignancies. We propose that universal implementation of NGS in cases of suspicious or confirmed myeloid malignancy will improve diagnostics, prognostics, and inform management decisions for patients with myeloid disease. Herein, we present our validation of the targeted Oncomine Myeloid NGS panel (Thermo Fisher). We further compare commercial variant analysis workflows accompanying the panel with a custom analysis pipeline, demonstrating that supplementing commercial filters with manual variant interpretation improves variant detection. We also performed prospective sequencing in patients with various myeloid malignancies, demonstrating that variants identified through molecular profiling can inform patient care. Additionally, we found that the detection of even a single variant, versus 0 variants, was independently predictive of overall survival. Furthermore, retrospective NGS of a cohort of individuals with suspicious or confirmed myeloid neoplasms (MN) with myelodysplasia facilitated the diagnosis of all suspicious cases as either MN or idiopathic cytopenia of undetermined significance (ICUS) or CCUS; the latter of which would otherwise have remained undiagnosed. We further assessed evolution of these precursor lesions to myeloid disease via serial sequencing. Our findings demonstrate the similarity of CCUS and low-risk MDS, supporting the proposal that CCUS should be classified accordingly in the next revision of the WHO guidelines. Finally, we present a case report of a single MDS patient, highlighting the value of serial sequencing in monitoring clonal evolution and disease progression, as well as the importance of comprehensive variant calling. Collectively, these findings highlight the importance of integrating NGS into routine clinical care for patients with idiopathic cytopenias and all types of myeloid malignancy.

abstract: PhD


title: Ec(h)oing across Borders: A Dialogue between Contemporary Environmental Literature and Ecocriticism in China and the Asian North American Context

contributor:
Fachinger, Petra
Cultural Studies

subject:
Cross-cultural
Ecocriticism
Asian North American literature
Chinese literature

abstract:
This Portfolio Project is a dialogue between Chinese and Asian North American contemporary environmental literature and ecocriticism. The cultural exchange between China and the West has a long history that has not always been smooth or reciprocal. I argue that Chinese ecocriticism develops in a more complicated way than that of the West partly because China is currently situated in pre-modern, modern and post-modern contexts simultaneously (Huang, “A Criticism” 31). Meanwhile, ecocriticism in North America has its own problems, including that voices of writers of Chinese descent are still very much in the background. There was a belated ecocritical interest of reading Asian North American literature, which partly results from the long-standing marginalization of Asian Americans and Asian Canadians due to racial discrimination. They also lacked agency in resisting complicit colonial decisions on the environment.
This project aims to promote knowledge mobilization between East and West. Chapter 1 provides a brief introduction to the Portfolio; Chapter 2 presents an overview of Chinese ecocriticism in the last ten years, in which I not only trace the development of Chinese ecocriticism but also address its significance and limitations. Chapter 3 shifts the focus from Chinese ecocriticism to Asian North American ecocriticism. My focus is on a few select texts of Asian North American environmental literature that discuss issues around food (in)security and the resilient power of ethnically and culturally specific food choices. This chapter is meant to build a foundation for more detailed and in-depth analysis of Chinese North American environmental texts as I demonstrate in Chapter 4, which discusses foraging as a form of transgression and resilience, and Chapter 5, which discusses access to clean water. This project aims to fill some of the critical gaps in the discussion of these two literary contexts and the dialogue between them in a speedy manner and to promote Sino-Western ecocritical exchanges.

abstract: PhD


title: Evaluating Industrial Activities and Its Social/Economic Impact in a Developing Country with Remotely Sensed Data: A Case Study of Eastern Economic Corridor, Thailand

contributor:
Chen, Dongmei
Geography and Planning

subject:
Remote sensing
Time-series of nighttime light
Industrial development
Socioeconomic impact
Space-time analysis
Poverty alleviation
Electricity consumption
Built-up areas

abstract:
The industrial park is one of economic development tools that is based on integrating different facilities for producing goods and services, including manufacturers, infrastructures, and logistical supports (i.e., roads, utilities, schools, and medical services). However, the assessment of industrial development and its impacts is challenging, and the study at the local level is still limited in developing countries because of the lack of resources and limited budgets. This thesis examines the feasibility of using remotely sensed data and various methods to assess industry development and its social/economic impacts locally using Thailand's Eastern Economic Corridor (EEC) as the case study area.

This dissertation includes four inter-related parts of studies. In the first part, a rapid extraction method was employed in Google Earth Engine (GEE) to identify the built-up areas and understand the development status. Due to the incomplete household surveys in Thailand, in the second part, the missing household income was imputed using the multiple imputation method based on K-NN function with demographic and satellite-derived data. In the third part, the local electricity consumption was estimated using a decision tree regression model based on the variables from the second part to indicate industrial and economic activities. Industrial growth and its impacts were investigated in the fourth part using time-series of nighttime light data, detecting space-time patterns through an emerging hotspot analysis tool. This phase aims to identify the development patterns and their spatial spillover effect on the multidimensional poverty index of surrounding neighborhoods. The multi-temporal nighttime lights data illustrated growth patterns and were significantly correlated to GDP (Gross Domestic Product). Industrial development mainly helps poverty reduction. However, about 15% of neighborhoods still showed an increase in poverty with a low quality of life due to population concentration. This research demonstrates that the remotely sensed data can help study industrial activities and their impacts at the local level and better understand the spatial association of human activities and their impact on communities. The results will benefit national and local governments to better understand the consequences of implementing industrial development policies in less developed countries.

abstract: PhD


title: Optimal Transport in Mechanism Design, Differential Games, and Ensemble Control

contributor:
Gharesifard, Bahman
Mathematics and Statistics

subject:
Matching equilibrium
Differential games
Averaged control
Optimization

abstract:
In this thesis, we study optimal transport problems arising in game and control-theoretic settings. The thesis has three parts; in part one we study a variation of the matching problem over a continuum of consumers and producers, where the producers are uncertain about their cost of production, in part two we study optimal transport problem in game-theoretic settings, and in part three we study optimal transport in ensemble control-theoretic settings.

In part one, using optimal transport theory, we provide conditions under which matching equilibrium exists. In part two and three, we provide sufficient condition for the existence and uniqueness of an optimal transport map and prove that it can be characterized as the gradient of some convex function.

abstract: PhD


title: Back to their Ancient Roots: A Comparative Analysis between The Tale of Bygone Years and the Historia Regum Britanniae

contributor:
Siljak, Ana
History

subject:
Rus
The Primary Chronicle
Historia Regum Britanniae
Cultural Exchange
Literary Heritage
Medieval Europe

abstract: Historians have usually focused on the history of Kyivan Rus′ either by itself or in relation to Byzantine history. This is especially evident in the way that scholars have labeled allusions to antiquity in the PVL as ‘Byzantine’. Accordingly, this project explicates the influence of ancient literature upon the culture of Rusian ecclesiastics and nobility during the eleventh and twelfth centuries. This project focuses on analyzing two manuscripts, The Primary Chronicle/PVL (c. 1115) and Historia Regum Britanniae/HRB (c. 1138), as well as other texts that influenced them, which date to various times from the sixth to the twelfth centuries. I argue that references to similar stories and personae in the PVL and HRB reflect a common intellectual heritage for both Rus′ and Western Europe which was rooted in Biblical antiquity. Chapter I compares three manuscripts that influenced HRB, namely Gildas’ Regarding the Ruin of Britain (c. 530), Bede’s Ecclesiastical History of the English People (c. 731) and Nennius’ History of the Britons (c. 828), wherein I demonstrate that historians in early medieval Britain perceived historical continuity between their own societies and those of the ancient world, especially Biblical Israel and classical Rome. Chapter II compares Ilarion’s Sermon on Law and Grace (1047-150), The Tale and Passion and Encomium of Boris and Glěb (c. 1072) and Klim Smoljatic’s Epistle to Foma (1147), demonstrating that these manuscripts also draw causal connections between figures and events of the Biblical world and the history of Rus′. Having established the literary contexts for each manuscript, I demonstrate in chapter III that both the PVL and HRB explain the rise and decline of Rus′ and Britain in direct relation to events of the Biblical and classical world. This analysis elucidates how the PVL was composed through cultural exchange and how Rusian culture had developed intellectually by the early twelfth century in relation to Western European regions such as Britain.

abstract: M.A.


title: Melanoma Diagnostic Processes and the Occurrence of Advanced Disease in Ontario

contributor:
Hanna, Timothy
Groome, Patti
Public Health Sciences

subject:
Epidemiology
Melanoma
Diagnostic delay
Diagnostic interval
Diagnostic pathways
Health services research

abstract:
Background: Reasons for the occurrence of advanced melanoma and an understanding of melanoma diagnostic processes and their relationship with advanced disease is understudied.
Methods: This thesis examined the melanoma diagnostic process in Ontario using abstracted pathology reports and administrative data held at ICES. Objective 1 described the occurrence of advanced melanoma using abstracted pathology reports on a 65% random sample of people diagnosed with melanoma in Ontario from 2007–2012. We used modified Poisson regression to identify factors associated with advanced melanoma, stratifying by ulceration, which is a marker of clinical appearance and prognosis. Objectives 2–4 used ICES data. Objective 2 described the melanoma diagnostic interval (DI) for all Ontario melanoma patients diagnosed from 2007–2019. We used quantile regression to evaluate the association between patient-, disease-, and system-level factors and the length of the DI and primary care (PCI) and specialist care (SCI) subintervals. Objective 3 used latent class cluster analysis to group patients who experienced similar diagnostic processes. Objective 4 used quantile regression with restricted cubic splines to examine the relationship between melanoma thickness and DI length, stratified by ulceration.
Results: Advanced melanoma was diagnosed in 26% of patients, and age, sex, socioeconomic status, and health region were associated with an increased risk of advanced disease. Ulceration attenuated these effects. Median DI was 36 days (Interquartile range [IQR]: 8–85 days), PCI was 22 days (IQR: 6–54 days) and SCI was 6 days (IQR: 1–42 days). Different factors were associated with the lengths of the DI, PCI, and SCI. We identified four diagnostic pathways: “primary care only”, “referred to specialist for immediate action”, “multiple visits and procedures in SCI”, and “specialist care only”. The distribution of patient-, disease-, and system-level factors, along with the lengths of the DI, PCI, and SCI varied across pathways. Finally, we found a complex relationship between thickness and DI duration, which differed by ulceration.
Conclusions: We found independent risk factors for advanced melanoma in Ontario. This research identified variation in the melanoma diagnostic process within, and across, Ontario. We did not find a significant association between a longer DI and thicker melanomas.

abstract: PhD


title: Computational Modal Analysis of a Hydraulic Pump Support Structure for a Business Aircraft

contributor:
Mechefske, Chris
Kersten, Simon
Mechanical and Materials Engineering

subject:
Vibrations
Modal Analysis
Finite Element Analysis
Aerospace Design

abstract: Computational modal analysis performed using finite element analysis is a well-established method for estimating the modal parameters of complex structures. The work presented here aims to provide an insight into the techniques necessary to model structural components of a business jet fuselage through computational modal analysis of a rear-mounted pump support structure. The results of the computational modal analysis will be used to further aid in the understanding of the vibratory transmission path from the support structure to the fuselage cabin. The frequency response functions were used to validate the finite element model via a visual and analytical comparison against experimental data. The preliminary model was constructed in Altair Hyperworks and a modal frequency response analysis was used to estimate the dynamic response at a discrete set of points on the structure. The model validation study showed a reasonable correlation of the experimental and computational results for frequencies between 100 – 2000 Hz. The average percent difference of the center frequencies for the two models across the 20 – 4000 Hz bandwidth was 11.68 %. Two case studies were conducted on updated models of the pump support structure to provide an understanding of the effect of structural changes on the modal frequency response. Modifications were made to the webbing of the pump support yoke as well as the in-board and out-board isolator plates. These tests confirmed that differences between the frequency responses of the preliminary and updated finite element models can be justified using modal analysis theory. It was found that the structural design changes were not significant enough to impactfully influence the modal response of the structure. The methodology presented in this work provides an outline for future modelling and analysis of this generic business aircraft design.

abstract: M.A.Sc.


title: Controls on DOC Flux in Continuous Permafrost Watersheds

contributor:
Lafreniere, Melissa
Mabee, Warren
Geography and Planning

subject:
Dissolves Organic Carbon
Permafrost
Transport-Limited
Soil and Water Assessment Tool (SWAT)
Canadian High Arctic
Soil organic carbon

abstract:
The overarching purpose of this study is to develop a framework to model dissolved organic carbon (DOC) flux using only surface runoff and/or remotely acquired biophysical (terrain, vegetation, soil) data in environments that are remote and/or have limited data. To achieve this, this study focuses on (1) establishing a correlation between daily DOC flux and daily surface discharge, (2) finding a relationship between soil physical characteristics and soil organic carbon-SOC (source of DOC carbon), and (3) assessing the accuracy of a modelling tool in hydrologic modelling of watersheds on continuous permafrost in the High Arctic.
The results of this work demonstrate that there is a significant positive correlation between surface runoff and DOC flux, except in the cases of surface physical disturbance which can increase both discharge and DOC flux. The work also determines that High Arctic watersheds, similar to other watersheds in North America, are transport limited (DOC controlled by discharge) for all the runoff components (nival, base and stormflow). The analyses found a statistically significant correlation between soil moisture and SOC, demonstrating that remotely acquired soil moisture data could help map SOC in watersheds on continuous permafrost in the High Arctic, which could improve carbon stocks estimates in the region. The significance of spatial variability of SOC builds on the importance of using a spatial hydrological modelling tool in High Arctic watersheds. SWAT was chosen as an appropriate tool; assessment of this tool showed that snow-related parameters, particularly snowmelt temperature, greatly influences the modelled discharge, while the soil parameters have little to no impact on the modelling output.
Overall, the study found that the highest contributor to the total discharge is snowmelt, except when rainfall events are very high, and stormflow becomes the largest contributor to discharge. The increase in rainfall dominance is part of the climatic predictions of the Arctic, therefore, a shift between nival flow (NF) and stormflow (SF) could be observed by the end of the century. The research establishes a robust correlation between soil moisture and SOC, river discharge and DOC flux and provides an approach to modelling discharge which is not reliant on field observations

abstract: PhD


title: Investigating the Effect of Tumour Suppressor PTEN/DAF-18 Variants and Mammalian Insulin on the Insulin and Insulin-like Signaling Pathway in Caenorhabditis elegans

contributor:
Chin-Sang, Ian
Biology

subject:
C elegans
human insulin
PTEN
DAF-18

abstract: The insulin and insulin-like growth factor signaling (IIS) pathway is an anabolic, growth stimulating pathway highly conserved among humans and Caenorhabditis elegans (C. elegans). In humans, the tumour suppressor protein Phosphatase and Tensin Homolog (PTEN) inhibits IIS, preventing excessive growth and development. The first aim of this research was to explore the effect of mammalian insulin on the development of C. elegans. A potential treatment for diseases involving hyperactivation of the IIS pathway might involve an engineered antagonistic human insulin which could bind to the insulin receptor and downregulate it through competitive inhibition. However, if C. elegans is to be used as a model to study human insulin, we first need to elucidate the effect of the human insulin on C. elegans. If human insulin can have an agonistic effect on our model organism, then we might be able to use it as an assay to assess the function of human insulin in vivo. In our research, we found that human insulin behaves as an antagonist when expressed transgenically, but agonistically when delivered exogenously. Furthermore, the antagonistic effects of transgenic human insulin were mediated by co-injection of F peptide, a peptide found in agonistic insulins of C. elegans. The second aim of this thesis was to characterize variants of the human tumour suppressor PTEN implicated in autism spectrum disorder (ASD) by looking at the effect of 5 variants in the homologous C. elegans protein DAF-18. By determining the effects of these mutations, we can potentially infer how these variants play a role in human disease formation, such as the development of ASD. We found that variants D66E, L115V, and H168Q are more likely to be benign while variants H138R and T176I are more likely to be pathogenic. Overall, this work reveals the effect of human insulin on the C. elegans IIS pathway and characterizes several variants of unknown significance of the PTEN protein, which has the potential to be clinically relevant when it comes to diseases involving dysregulated insulin signaling such as hyperinsulinemia or cancer.

abstract: M.Sc.


title: The Magician, the Magical Creature, and the Priest: The Division of Labour Between Magical Beings and the Church in Kievan Rus’ and Muscovy

subject:
Kievan Rus
Muscovy
Russia
Ukraine
Medieval
Religion
Magic
Magicians
Labour
Church History
Eastern Orthodox Christianity

abstract: This thesis explores how magicians and magical creatures worked with the church and Christianity in Kievan Rus’ and Muscovy from the tenth to seventeenth centuries. By using folk tales, chronicles, statutes, household manuals, and lexicographical dictionaries, an examination is presented of the ways in which magicians and magical creatures were believed to provide services to people that were not fulfilled – or not fulfilled completely – by the church and orthodox religion.

abstract: M.A.


title: Learning from Experience: Novices' Journey Through An Evaluation

contributor:
Searle, Michelle
Education

subject:
program evaluation
novice
experiential learning
collaboration
self-study

abstract:
The field of evaluation is expanding and there is a growing need for trained evaluators to enter the workforce. To meet these demands, it is important for those who want to enter this profession to be equipped with the necessary knowledge and skills to conduct program evaluations. The literature on the best practices to train evaluators continues to grow and this thesis documents the learning journey for myself and two other novice evaluators on our journey conducting an evaluation. Using self-study and collaborative inquiry, this research answered the following questions: (1) What attitudes, competencies and skills were developed through conducting this evaluation? (2) What aspects of this experience contributed to our growth and in what ways could these be considered for future experiential learning opportunities? (3) What were some of the successes and challenges of conducting an evaluation as a novice evaluator?
	Through a mixed-methods approach, analysis found that this experiential learning opportunity was successful in contributing to the development of skills across all evaluation domains and played an important role in my changed attitude towards evaluation and collaboration. The collaborative nature of the evaluation both within the team and with our collaborator also contributed to the success of this project. Lastly, the experiential nature of the project, being able to collaborate with a real organization was an integral part of our experience. This thesis concludes with a discussion on the implications of the findings for evaluation novices, groups learning evaluation, evaluation instructors and the field of evaluation overall.

abstract: M.Ed.


title: Electrophysiology of Memory Consolidation and Epileptogenesis in the Primate Mesial Temporal Lobe. Effects of Focal Seizures with Impaired Awareness

contributor:
Levy, Ron
Neuroscience Studies

subject:
Epilepsy
Deep brain stimulation
Episodic memory
Non-human primates
Sharp-wave ripples
Ketamine
Hippocampus

abstract:
Epilepsy is a disorder characterized by unprovoked, recurrent seizures and affects approximately 350,000 Canadians. A third of this population have seizures that are refractory. This leaves over 100,000 people with uncontrolled seizures. Poorly managed seizures commonly cause cognitive dysfunctions, like learning and memory impairments, which can be devastating to individuals and society. Given that epilepsy arises from disturbances in electrical brain function, there is an opportunity to learn about these disturbances by studying electrophysiologic changes, which occur in a network that supports memory consolidation, during epileptogenesis.
The first aim of this project was to characterize the electrophysiology of memory consolidation in healthy non-human primates (NHPs). It was hypothesized that this characterization would approximate that of other animal models such as rodents. It was also hypothesized that pharmacologic manipulations known to impair memory would predictably disrupt baseline electrophysiology. Neural signals were recorded from rhesus macaques performing associative and spatial memory tasks in a 3D virtual reality environment. Results of aim 1 demonstrated that, in addition to being associated with learning, as it is with other animal models, sharp-wave ripple (SWR) occurrence was correlated with mismatches in expectation and perception. Incorrect target choices, steering errors and surprise rewards correlated with SWRs in NHP. Subanesthetic ketamine predictably altered excitability as measured by field-evoked potentials (fEPs) and connectivity and upper thresholds for fEP elicitation were determined.
The second aim was to develop a stimulation technique to induce focal seizures with impaired awareness (FIAS) in NHP. It was hypothesized that weekly kindling would cause the stable development of FIAS and that epileptogenesis would alter baseline physiology. Electrophysiology was compared to aim 1, dynamics of electrographic seizures were examined and clinical semiology was monitored. Results of aim 2 demonstrated that kindling could be used to induce FIAS which altered electrophysiology and behaviour from baseline.
This work highlights unique electrophysiologic processes underpinning memory in primates. It describes a stable model of FIAS which is used to study MTL alterations due to drugs and epileptogenesis. Together these results inform research and clinical practice regarding the generation of seizures, study of memory and use of electrical brain stimulation.

abstract: PhD


title: FEMALE RISK FACTORS FOR POST-INFARCTION DEPRESSION AND ANXIETY: THE FRIDA STUDY

contributor:
Johri, Amer M.
Translational Medicine

subject:
cardiology
depression
anxiety
acute coronary syndrome
psychiatry
female

abstract: Cardiovascular disease (CVD) is the leading global cause of mortality, with ischemic heart disease causing the majority of CV deaths. CVD is traditionally considered to be most prominent in males. Yet, female patients demonstrate a higher mortality rate than males within a year of acute coronary syndrome (ACS) and at the five-year mark. Several studies demonstrate that female patients are significantly more likely to experience depression and anxiety following ACS, correlated with higher rates of CV morbidity, mortality, and rehospitalization. Revised guidelines to address mental health following ACS may be developed with support from studies identifying the CV risk factors and psychosocial determinants of health that elevate risk in female patients. We aimed to identify the CV risk factors, demographic, and socioeconomic variables correlated with increased Hospital Anxiety and Depression Scale (HADS) scores (HADS-Depression ≥8; HADS-Anxiety ≥8) at the time of an acute coronary event (within 72 hours of ACS). We further set out to determine whether increased depression and anxiety scores at baseline correlate with three and six-month outcomes (repeated HADS questionnaire, Cardiac Anxiety Questionnaire, major adverse cardiac events (MACE), Short Form-12 Health Survey, and Somatic Symptom Scale-8). This prospective multi-center questionnaire-based clinical research study features data collected at baseline and at three and six months plus statistically computed descriptive and inferential values (Fisher Exact test for binary variables, T-test for continuous variable (age), linear odds ratios, logistic regression) used to observe distributions and significance between groups. We identify a key group of variables associated with HADS-A≥8 (low income, previous history of mental illness, and low social support) as well as HADS-D≥8 (gender, unemployment, low income, unstable housing, previous history of mental illness, stress, and low social support). Our results can inform tailored interventions following ACS in primary care and cardiac rehabilitation while understanding identified risk factor correlations can better inform prevention strategies at the public health level.

abstract: M.Sc.


title: Investigating the Interplay Between Endothelial BMPR2 Loss, Interleukin-15 Signaling, and Sex Hormones in the Pathogenesis of Pulmonary Arterial Hypertension

contributor:
Ormiston, Mark L.
Biomedical and Molecular Sciences

subject:
PAH
NK Cells
BMPR2
Sex Differences

abstract:
Pulmonary arterial hypertension (PAH) is a disease of occlusive vascular remodeling, resulting in increased resistance in the lungs vasculature, progressive decrease in cardiac output, and eventually death from right heart failure within 3-5 years of diagnosis if left untreated. PAH is strongly associated with mutations in the gene encoding the type-II bone morphogenetic protein receptor (BMPR2), female sex, and immune dysfunction. However, the molecular mechanisms by which these factors contribute to disease development, or the interplay between them, remains poorly understood.

The work presented in this thesis explores how the loss of interleukin-15 (IL-15), a major homeostatic regulator of natural killer (NK) cells, contributes to disease development in two major rat models of PAH. Additionally, this work examines how endothelial BMPR2 loss impacts IL-15 signaling in vitro and examines how endothelial Bmpr2 loss in mice impacts their circulating immune phenotype. Finally, this work assesses the impact of gonad-derived sex hormones on disease severity in NK cell-deficient Il15 knockout (Il15-/-) rats in disease.

These studies demonstrate that loss of IL-15 and NK cells exacerbates disease in experimental models of PAH. Additionally, this work shows that the loss of endothelial BMPR2 results in decreased surface presentation and secretion of the major IL-15 receptor (IL-15Ra) via impaired trafficking through the trans-Golgi network (TGN). Finally, studies assessing the effects of gonad-derived sex hormones on disease severity demonstrate a novel interplay between NK cells and estrogen in right ventricular remodeling. The presented work highlights previously unappreciated links between the genetic basis of PAH, NK cells, and sex hormones in both pulmonary vascular and right ventricular remodeling in PAH.

abstract: PhD


title: Fatigue Strengthening of Damaged Steel Plates using Ultra-High Modulus Carbon Fibre-reinforced Polymer Plates

contributor:
Fam, Amir
Woods, Joshua
Civil Engineering

subject:
fatigue
steel
CFRP
ultra-high modulus
plate
patch
crack
stress concentration

abstract: This study evaluates the effectiveness of externally bonded small patch Ultra-high modulus (UHM) carbon-fiber reinforced polymer (CFRP) plates of 460 GPa modulus in extending fatigue life and slowing crack propagation in steel plates with simulated fatigue cracks. The study investigates a range of bond lengths at or below the development length of UHM CFRP for applications where bonding space may be limited or accessibility restricted, together with the effect of single- versus double-sided application, on fatigue performance. It also compares short UHM CFRP plates to similar length normal modulus (NM) (165 GPa) CFRP plates with regard to extending fatigue life and reducing stress concentration at notch tip.  Distributed fiber optic sensors (DFOS) and digital image correlation (DIC) are used to capture the full strain field and track crack growth. Results showed that fatigue life was increased by up to 2.0 and 2.34 times for single- and double-sided UHM CFRP repairs. As bond length increased from 25 to 100 mm, fatigue life increased from 1.36 to 2.0.  UHM CFRP more effectively reduced stress concentration at the notch tip, by 60% compared to 37% for NM CFRP, indicating that it has the potential for superior fatigue life gains, relative to NM CFRP, at longer bond lengths where debonding is prevented or delayed.  As debonding failure governed in this study, NM CFRP plates achieved comparable fatigue life extension.  DIC tracking of crack growth matched the traditional ‘beach marking’ technique with less than 6% difference.

abstract: M.A.Sc.


title: Design and Validation of an Open-Source 3D Printable Bioreactor System for Ex Vivo Bone Culture

contributor:
Rainbow, Roshni
Ploeg, Heidi-Lynn
Mechanical and Materials Engineering

subject:
3D Printing
Bone Organ Culture
Bioreactor
Biomechanics
Cell Culture
MED610

abstract: In Canada, osteoporosis is a prevailing skeletal disease that is underdiagnosed and undertreated, with an annual economic cost of $4.6 billion. Trabecular bone is widely understood to undergo modelling and remodelling in response to biochemical and mechanical loads during physical activity. Further insights into the adaptation process of bone could help clinicians improve prevention and treatment methods, including physical activity recommendations, and lead to increased bone health. Previous studies have successfully implemented a polycarbonate (PC) bioreactor system to study trabecular bone adaptation in response to biochemical and mechanical stimulation in long-term ex vivo bone organ culture. However, the PC bioreactors are expensive and difficult to fabricate and have been limited to testing bone cores with maximum dimensions of 5 mm x 10 mm (height x diameter), which is below recommended standards for bone compression testing. Recent advancements in additive manufacturing can reduce fabrication cost and difficulty and allow for high dimensional precision in 3D printed designs with biocompatible material options. Thus, the first objective of the presented research was to develop an open-source 3D printable bioreactor with the photopolymer MED610TM that addresses the PC bioreactors fabrication and bone core height limitations. The second objective was to test the role of the MED610TM material on cell viability and determine a cleaning and sterilization protocol for MED610TM in cell and tissue culture applications. Finally, the third objective was to validate the 3D printed bioreactor in an ex vivo bovine trabecular bone study with mechanical stimulation by measuring the change in apparent elastic modulus over 21-days. Collectively, this thesis demonstrated that 3D printed MED610TM bioreactors cleaned and sterilized with a sonication and autoclave protocol are suitable for ex vivo bone organ culture and can replicate trends in trabecular bone apparent elastic modulus found in previous studies. Recommendations for next steps are provided including adjustments to the bioreactor design and continued biocompatibility and validation testing.

abstract: M.A.Sc.


title: Transformations of Phosphonates by Non-Heme Iron-Dependent Oxygenases

contributor:
Zechel, David
Chemistry

subject: Biochemistry Enzymes Chemistry

abstract:
Inorganic phosphate (Pi) is an essential requirement of all life forms; however, Pi is not present in high abundance in the environment.  This has driven microorganisms to evolve enzymes that cleave carbon-phosphorus (C-P) bonds that enable the use of organophosphonates (Pn) as an alternative source of Pi.  The iron-dependent oxidative PhnY*/PhnZ pathway is known to convert 2-aminoethylphosphonic acid into glycine and Pi. Recent work by our lab has revealed that the homologs GmPhnY* and GmPhnZ1 from the marine bacterium Gimesia maris have a different substrate specificity, oxidatively transforming methylphosphonic acid into formic acid and Pi. We have used 31P NMR spectroscopy to determine enzyme activity for a variety of Pn substrates with GmPhnY* and GmPhnZ1. The EFI-EST server was used to create sequence similarity networks (SSNs) of PhnY* and PhnZ homologs to investigate how families of enzymes may correlate with substrate specificity. Based on the results from our SSNs we have carried out site directed mutagenesis to explore the molecular determinants of substrate specificity in PhnZ. Furthermore, we have investigated other clusters in the PhnZ SSN to find novel PhnZ enzymes which may have a broader substrate specificity.
The fungal metabolite Fosfonochlorin is a rare example of a halogenated organophosphonate (Pn) with an unknown biosynthetic origin. A gene cluster encoding Fosfonochlorin biosynthesis was identified in Fusarium and Talaromyces sp. genomes by the occurrence of phosphoenolpyruvate mutase and phosphonopyruvate decarboxylase genes which are known to occur in the biosynthetic pathways of many other Pns. Other gene products from this cluster have been selected for further study, including FfnC and FfnD. FfnC is shown to be a new example of an NADH-dependent aldehyde reductase that converts phosphonoacetaldehyde into 2-hydroxyethylphosphonic acid. FfnD is shown to be a non-heme iron / 2-oxoglutarate (Fe/2OG) dependent oxacyclase. It transforms 2-hydroxyethylphosphonic acid into epoxyethylphosphonic acid and can convert ethylphosphonic acid into 1-hydroxyethylphosphonic acid. SSNs and genome neighbourhood networks (GNNs) have been used to determine further potential gene candidates that may be present in the Fosfonochlorin biosynthetic pathway by identifying gene homology in clusters with known Fosfonochlorin producers.

abstract: M.Sc.


title: Avionics Network Anomaly Detection through True-Skip Learning

contributor:
Ding, Steven
Computing

subject:
neural networks
cybersecurity
deep learning
cyber-physical systems
Avionics

abstract: MIL-STD-1553 is a communication bus that has been used by many military avionics platforms such as the F-15 and F-35 fighter jets for almost 50 years.  Recently, it has become clear that the lack of security on MIL-STD-1553 and the requirement for internet communication between planes have revealed numerous potential attack vectors for malicious parties.  Prevention of these attacks by modernizing the MIL-STD-1553 is not practical due to the military applications and existing far-reaching installations of the bus.  We present a software system that can simulate bus transmissions to create easy, replicable, and large datasets of MIL-STD-1553 communications with simulated attacks.  We also propose an intrusion detection system (IDS) that can identify anomalies and the precise type of attack using recurrent neural networks with a reinforcement learning true-skip data selection algorithm.  Our IDS outperforms existing algorithms designed for MIL-STD-1553 in binary anomaly detection tasks while also performing attack classification and minimizing computational resource cost.  Our simulator can generate more data with higher fidelity than existing methods and integrate attack scenarios with greater detail.  Furthermore, the simulator and IDS can be combined to form a web-based attack-defense game.

abstract: M.Sc.


title: Online Learning in Control Theory

contributor:
Gharesifard, Bahman
Linder, Tamas
Mathematics and Statistics

subject:
Online Learning
Optimal Control
Linear Quadratic Gaussian
Regret Minimization

abstract:
In this thesis, we study two classes of problems in optimal control theory involving unknown parameters, with focus on Linear-Quadratic-Gaussian systems.

In the first problem, the control system is known and linear, and a sequence of quadratic cost functions is revealed to the controller in hindsight. The controller aims to achieve a sublinear regret, similar to the online optimization setting. A modified online Riccati algorithm is introduced that under some uniform boundedness assumptions results in a logarithmic regret bound. In particular, the logarithmic regret for the scalar case is achieved without any extra condition, while in the vector case we impose a uniform boundedness assumption. In addition to having a better regret bound, the proposed algorithm has reduced complexity compared to the ones in the literature which mainly rely on solving semi-definite programs in each time step.

In the second problem, the true system transition parameters (matrices A and B) are unknown, and the objective is to design and analyze algorithms that generate control policies with sublinear regret. Recent studies show that when the system parameters are fully unknown, for any algorithm that only uses data from the past system trajectory there exists a choice of the unknown parameters such that the algorithm at best achieves a square-root regret bound, providing a hard fundamental limit on the achievable regret in general. However, it is known that (poly)-logarithmic regret is achievable when only matrix A, or only matrix B is unknown. We prove a result, showing that (poly)-logarithmic regret is achievable when both of these matrices are unknown, but a hint about one of them is given to the learner periodically. This result is the first attempt to achieve poly-logarithmic regret for the case that both A and B are unknown under milder assumptions.

abstract: PhD


title: Investigating the Role of Neuropeptide Receptors npr-16 and npr-24 in Caenorhabditis elegans

contributor:
Bendena, William
Biology

subject:
C elegans
neuropeptide receptor
Allatostatin C

abstract: The conserved neuropeptide signaling pathway in C. elegans provides a promising opportunity to further advance our knowledge regarding the molecular basis of behaviour and physiology in higher organisms while paving the way for potential development of therapies for various neurodegenerative disorders. In mammals, the peptide hormone family somatostatin comprises a group of various secretory proteins that control neurotransmission, metabolism, and memory by acting on their respective G-Protein Coupled Receptor (GPCR) to inhibit downstream growth-related genes. In C. elegans over 50 GPCRs act as neuropeptide receptors (npr), many of which have mammalian orthologs including npr-16 and npr-24. Thus, characterization of these receptors will allow discovery of analogous somatostatin signaling in C. elegans that can be used for studying the impact of specific neuropeptide and hormonal dysregulation in humans. Through phenotypic and genetic analysis, we aim to examine the role of npr-16 and npr-24 in C. elegans and determine the potential pathways they operate in by establishing an evolutionary link across species. Our work has determined the impact of knock out mutations on key growth phenotypes in of the C. elegans, including longevity and vitellogenesis, as well as their role in metabolism as shown through the distinct increase in fat content. Furthermore, we have observed a potential evolutionary link between C. elegans npr-16 and npr-24 and Drosophila allatostatin-C by examining the impact of the mutation on key enzymes involved in Juvenile hormone biosynthesis. Characterization of npr-16 and npr-24 will provide a unique opportunity to enhance our knowledge about growth and development in C. elegans and aid further somatostatin-related therapeutic studies in this model organism.

abstract: M.Sc.


title: Baked In Like a Muffin: the Culture of Whiteness in Ontario Elementary Schools

contributor:
Pillay, Thashika
Education

rights: Attribution-NonCommercial 3.0 United States

subject:
Critical consciousness
Critical race theory
Qualitative research

abstract: As a newly certified teacher in 2015, I began my teaching journey in the Peel District School Board with limited experience developing my critical consciousness nor recognizing the importance of doing so. I thought teaching students equitably could be achieved by treating all students the same. One of the many issues with this mentality was my positionality as a white female dictated my understanding of equity in the classroom. My subconscious/conscious biases, assessments, resources, expectations of students and teaching strategies were influenced by the culture of whiteness. This influence and perpetuation stems from the socialization of race and colonialism, which has been ingrained into society for centuries (Goldberg, 1992; Feagin, 2013). This translates to racialized students experiencing racism and oppression throughout their schooling, which leads to lower graduation rates and educational outcomes (Carr, 2008; Dei, 2003; Lopez & Jean-Marie, 2021). Upon personal reflection, I see how I reinforced colonial systems in my teaching. This realization drove my desire to deepen my critical consciousness and conduct this work, as I share white intermediate teachers’ experiences reflecting on the culture of whiteness and systems of oppression within schools in the Greater Toronto Area. The following research questions guide this study: 1A) How is the culture of whiteness perpetuated by white intermediate teachers in the Greater Toronto Area? 1B) How does the culture of whiteness impact the pedagogies and resources teachers use in intermediate classes in Ontario? 2) What tools are white teachers using to mitigate the perpetuation of the culture of whiteness and develop their critical consciousness? 3) What changes need to be implemented to mitigate the perpetuation of the culture of whiteness in teaching (i.e., structural, institutional, and/or systemic)? These questions are addressed through data collected from semi-structured interviews that formed a single case study research design. The findings highlight how the culture of whiteness is maintained, tools to deepen one’s critical consciousness, as well as recommendations to disrupt the culture of whiteness in education.

abstract: M.Ed.


title: Moral Phenomenology in a More-Than-Human World: A New Approach to Buddhist Environmental Ethics

contributor:
Goldberg, Ellen
Cultural Studies

subject:
Buddhism
Tibetan Buddhism
Religious Ecology
Environmental Ethics
Animal Ethics
Environmental Philosophy
Buddhist Ethics
Eco-Buddhism
Contemplative Studies
Meditation

abstract:
This dissertation works to accomplish two goals. First, it defends Jay Garfield’s interpretation of Buddhist ethics as a moral phenomenology and develops this ethical system through the Tibetan framework of lta sgom spyod gsum. Second, it looks at how this interpretation of Buddhist ethics can be applied to the more-than-human world to create a novel Buddhist environmental ethic. The first half defends a moral phenomenological interpretation of Buddhist ethics and develops
this theory through the framework of lta sgom spyod gsum. To do so, it surveys prior interpretations of Buddhist ethics to provide a foil for the discussion before turning to the arguments for a moral phenomenological interpretation. It then defends this interpretation in the context of the Mahāyāna and Vajrayāna traditions of Tibet and both raises and responds to possible issues in a Buddhist moral phenomenology. This dissertation then turns its attention to view, meditation, action as the framework for moral phenomenological praxis. It surveys the ways this framework has been employed in Tibetan contexts before applying this framework to moral phenomenology. It nuances this approach by asking what ‘view’ really means in this context and investigates how meditation and direct meditative experience function to bring a view into one’s default perceptual mode in order to inform one’s action. Part two applies this theory and framework to contemporary issues facing the more-than-human world. It first surveys prior Buddhist environmental ethics before looking at how phenomenology has been given attention in environmental philosophy. It then articulates what an applied moral phenomenology would look like and what specific problems a moral phenomenological approach to environmental ethics can address. Finally, this dissertation proposes a moral phenomenological approach to environmental ethics by searching for an ecological view, analyzing how meditation functions in this context, and considering what the resultant action looks like. In doing so, it shows how moral phenomenology and its implementation through view, meditation, action can be applied to contemporary issues outside the specifics of the Buddhist tradition and can provide novel approaches to solving issues like climate change and the degradation of the more-than-human world.

abstract: PhD


title: Survival Time Prediction with Radiographic Images for Primary and Metastatic Liver Cancers

contributor:
Simpson, Amber
Ellis, Randy E
Computing

subject:
Survival prediction
Radiomics
Machine learning
Liver cancer

abstract:
Incidence and mortality of primary and metastatic liver cancers are rising worldwide, and have poor prognosis due to high recurrence rates. Prognostic biomarkers of specific patterns of disease progression are critical to selecting patients for individualized therapy including “go/no go” decision-making for hepatic resection, and choice of systemic chemotherapy or regional chemotherapy, treatments known to prevent recurrence. Survival analysis, a branch of statistics dedicated to studying the time to an event, such as death or cancer recurrence, is commonly used to find relationships between clinicopathological variables and disease outcome. Radiologists and oncologists derive important information from radiographic images, such as computed tomography (CT) scans. We hypothesized that prognostic biomarkers can be derived from preoperative CT scans of primary and metastatic liver cancers using machine learning approaches. In this thesis, we compared the performance of three models of increasing complexity for the task of predicting the time between surgical resection and recurrence: a Cox Proportional Hazards regression and Random Survival Forest model, developed using hand-crafted radiomic features, and a convolutional neural network, a deep learning method capable of automatically determining features. Multi-centre retrospectively accessed data was acquired for patients who underwent curative resection as treatment for hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (ICC), and metastatic colorectal cancer (MCRC). Four hundred and ninety-six patients were included in the analysis.

This work had three main contributions. The first showed that a single model was capable of predicting survival for multiple liver cancer types. The second contribution was to provide a rigorous analysis of the performance of each model with appropriate considerations for patients lost to follow-up. The third contribution was a first application of machine learning methods to a large ICC cohort.
The radiomics-based models performed the best, achieving results comparable to those shown in existing literature in this field, and the methodology presented was a first step towards the exploration of these cancers using deep learning. Our results show that there was prognostic signal available for our data from primary and metastatic liver cancers in radiographic images.

abstract: M.Sc.


title: Blue Planet: Place, Paradox, and Staying on Earth in Contemporary Science Fiction

contributor:
Wallace, Molly
Willmott, Glenn
English Language and Literature

subject:
Science fiction
Speculative fiction
Avatar
Interstellar
The Expanse
The Martian
Ecocriticism
Genre
Film
Literature
Mars
Earth
Andy Weir
James S.A. Corey
Elon Musk
Jeff Bezos
William Shatner
Climate change
Global warming
Environment
Nature
Outer space
Timothy Morton
Star Trek
Atopia
Utopia
Dystopia
Heterotopia
SpaceX
Ridley Scott
James Cameron
Christopher Nolan
Planet B
David Attenborough
Blue Planet
Red Planets
Green Planets
Gerry Canavan
Kim Stanley Robinson
Frederic Jameson
Nostalgia
2010s
Escapism
sf
sci-fi
Blue Origin
Matt Damon
Place
Paradox
Irony
Stephen Hawking

abstract: This project examines the intersection of contemporary environmental and social anxieties present in the science fiction (sf) of the 2010s by close reading and analyzing a range of sf texts, films, and other multimedia from the decade. This study reveals that environmental and ecological preoccupations, ranging from the crisis of climate change, collapse of ecosystems, global loss of biodiversity, and their resulting human societal implications, became dominant themes of the genre over the course of the period. While the 2010s proved to be a decade overrun by environmental fatalism, the concomitant cosmic escapism proposed by figures like Elon Musk, Jeff Bezos, and Stephen Hawking, to name but a few, imagined a flight from the environmental and societal perils of Earth through the dream of colonizing outer space and Mars. However, I propose, many sf works produced during the decade often point in unexpected, paradoxical, and frequently ironic directions. This study examines sf works that, rather than revelling in humankind’s recent fascination with Mars and the stars, instead provide an alternative vision. An inherent paradox thus emerges in numerous contemporary examples of sf. I argue that stories about exploring other planets, colonizing new worlds, or fleeing the problems of home—like Andy Weir’s The Martian (2011), James Cameron’s Avatar (2009), Christopher Nolan’s Interstellar (2014), James S.A. Corey’s The Expanse series (2011–2022), and numerous others—do not support such actions. Instead, I contend, a recurring theme of sf of the 2010s is that humankind should stay home on Earth and focus on revitalizing our troubled planet and repairing human society and ourselves, rather than the rash plan of ditching our Blue Planet for Mars or some other impossible “Planet B” in outer space.

abstract: PhD


title: Corporal Punishment Bans, Childhood Adversity, and Adolescent Suicide Rates: An International Ecological Study

contributor:
Pickett, William
Elgar, Frank
Public Health Sciences

subject:
Suicide
Adolescent health
Mental health
Childhood adversity
Socioeconomic status
Corporal punishment
Epidemiology
Population-level study

abstract:
Corporal punishment is associated with poor mental health outcomes, including suicidal behaviour, in adolescents. At a population level, legislation banning corporal punishment is associated with many health outcomes in children. Therefore, the overarching objective of this thesis is to investigate the relationship between legislation banning corporal punishment and adolescent suicide rates across countries and cultures, both cross-sectionally and using time series methods. Sources of childhood adversity were explored as potential effect modifiers.

	This thesis used exclusively population level secondary data. Negative binomial models were constructed to investigate the cross-sectional objectives. Negative binomial mixed models were used to investigate the time series objectives.

	Compared to the 39 countries that had enacted a full ban (in homes, schools, daycares, and alternative care settings) of corporal punishment, the 19 countries that had not banned corporal punishment reported 2.07-fold the rate of suicide in females aged 15-19 (RR 2.07, 95% CI 1.07-4.01). Twenty countries that permitted corporal punishment in schools also reported a higher rate of suicide in female adolescents aged 15-19 (2.01-fold the rate of 77 countries that had banned school corporal punishment).

	There was evidence of lagged effects of partial bans of corporal punishment and bans of corporal punishment in schools; these effects peaked after 12 years for females aged 15-19 and after 13 years for males aged 15-19.

	There was no evidence of effect modification by the socio-economic (SES) Index. There was also no statistically significant evidence of effect modification by the Childhood Adversity (CHA) Index, but the interaction term for females aged 10-14 between partial bans of corporal punishment (bans enacted in some, but not all, of the four settings investigated) and the CHA Index approached statistical significance (RR 0.60, 95% CI 0.36-1.00, p-value 0.0502). The beneficial effects of banning corporal punishment in all settings may be reduced in countries with greater levels of childhood adversity.

	The results of this study add to a body of evidence that suggests that legislation banning corporal punishment may promote adolescent health and well-being. In combination with future research, these findings may be applied to reduce adolescent suicide rates at a national level.

abstract: M.Sc.


title: Evaluating New Adjuvant Combinations for Improving Pre-Clinical Cancer Immunotherapy in a B16-Melanoma Model

contributor:
Basta, Sameh
Biomedical and Molecular Sciences

subject:
Melanoma
Cancer Vaccine
Immunotherapy
IL-27
Toll-like receptors
CpG

abstract:
Whole tumour cell vaccines require the cells to be dead or dying, constituting a dead tumour cell vaccine (DTCV). A DTCV alone can be poorly immunogenic and requires the addition of adjuvants to promote a robust anti-tumour immune response. Cytokines and Toll-like receptor (TLR) agonists are used as cancer vaccine adjuvants. In this study, we evaluated how IL-27 and CpG can influence the efficacy of a DTCV in a pre-clinical murine B16-OVA melanoma model.
We first evaluated how different methods of inducing cell death impacted the efficacy of a DTCV in a prophylactic B16 melanoma model. We found that using LyUV (the combination of lysis and UV-irradiation) or -irradiation provided comparable protection against tumour challenges. We next investigated the use of IL-27, a pleiotropic cytokine, as an adjuvant. We reported that IL-27 can be used as an adjuvant in a DTCV and that a lower dose of IL-27 (10 ng/mouse), but not a higher dose (100 ng/mouse) improved protection.
Activated dendritic cells (DCs) can present tumour antigens to promote an anti-tumour immune response. Endosomal TLR agonists are used as vaccine adjuvants, and therefore we wanted to determine whether IL-27 altered DC activation in response to endosomal TLR agonists. We found that IL-27 and the CpG-ODN (1826), a TLR9 agonist, enhanced the expression of co-stimulatory molecules and promoted phagocytosis indicating improved DC activation. Lastly, we wanted to determine whether the combination of IL-27 and CpG-ODN could improve the efficacy of a DTCV. We determined that the combination of IL-27 and CpG successfully enhanced an anti-tumour immune response in both a prophylactic and therapeutic B16-OVA melanoma model.
These results indicated that the method of inducing cell death needs to be considered when generating a DTCV and that the dose of IL-27 can influence vaccine efficacy. These results also indicated that IL-27 and CpG can be combined as vaccine adjuvants to improve the efficacy of a DTCV in prophylactic and therapeutic models. The results presented herein lay the foundation for improving DTCVs and the importance of using adjuvant combinations to enhance vaccine efficacy.

abstract: PhD


title: Determination of Nickel and Platinum Species in Electrolyte Solutions With Inductively Coupled Plasma Mass Spectrometry Coupled to Cation Exchange Chromatography

contributor:
Beauchemin, Diane
Chemistry

subject:
Inductively Coupled Plasma
Mass Spectrometry
Speciation Analysis
Fuel Cell
Electrolyte
Ion Chromatography

abstract: Two methods utilizing cation exchange chromatography (CEC) coupled to inductively coupled plasma mass spectrometry (ICPMS) were developed in this thesis. The first method, for direct determination of trace nickel concentrations in alkaline electrolyte, was found to have a method detection limit for 58Ni of 0.5 μg L-1 in 0.5 M NaOH. When in KOH solutions of 2-6 M, a detection limit of 0.2 μg L-1 or better was achieved. The main issues with previous analysis of these solutions were suppression of the plasma due to the high amount of alkali species being introduced and degradation of the ICP components due to caustic OH-. These issues were overcome using a 6-port valve to divert the CEC effluent containing the Na+ or K+ and using a strong acid eluent, namely HNO¬¬3, to neutralize the sample. The second method was for the speciation analysis of Pt complexes in 0.5 M sulfuric acid, which bypasses the addition of complexing agents typically used in anion exchange methods by using CEC. The change in speciation of Pt in several standard solutions prepared from stocks of either tetrachloroplatinite (Pt II) or hexachloroplatinic acid (Pt IV) was monitored and optimization of the procedure was performed to maximize the sample throughput and the overall sensitivity for platinum.

abstract: M.Sc.