VictorJuiz/thesis huggingface dataset:
Type 2 Diabetes in South Asians – Exploring Risk Factors and Utilization of Healthcare in Canada

Type 2 diabetes is a serious chronic condition affecting millions of people worldwide. South Asians (individuals originating from Pakistan, India, Bangladesh, Sri Lanka, and Nepal) represent a high-risk ethnicity for developing type 2 diabetes (T2D) and experience a high prevalence of the disease, even in migrant populations. The objectives of this thesis were twofold: (1) to synthesize the latest literature on (i) risk factors that predispose South Asians to be at high-risk for T2D; (ii) utilization of diabetes-related healthcare services in Canada; and (2) investigate perceptions and experiences of South Asians living with T2D in Ontario, and their utilization of diabetes related services within the provincial healthcare system. The first objective was completed through a scoping review, while the second objective was achieved through 20 in-depth interviews. Findings from these interviews are discussed and broader policy options are recommended.

Keywords: Health geography
Healthcare utilization
Immigration Health
Revised Andersen's Behaviour Model
South Asian
Type 2 Diabetes
Advisor: Kuuire, Vincent Z.
The Drama of Democracy: Theatricality, Histrionics, and the Attention Economy in US Presidential Elections (2008-2020)

This work considers the two most-recent American presidential administrations – that of former President Barack Obama (2008-2016) and former President Donald Trump (2016-2020) – in order to investigate how the theatricality that permeates the American electoral system has undercut both theoretical discourses of democracy as well as its intended practical application. The election of Barack Obama (particularly in 2007/8) is demonstrative of the dangers posed by new modes of theatricality proliferated by the digitalization and virtualization of the campaign trail. Donald Trump’s campaigns applied theatrics that can be traced to the inter-war period, while also conforming to the digital age of performance. The analysis is accompanied by an atlas of dramatizations, with each individual piece confronting a political moment that has destabilized the democratic narrative from within the repertoire of four US elections. In resurrecting these cases, this thesis warns of the electorate’s inability to separate theatre from policy.

Keywords: american
attention economy
democracy
elections
performance studies
theatricality
Advisor: Cesare Schotzko, T. Nikki
Identification of Candidate Lyme Disease Vascular Adhesins Supporting Tissue-specific Endothelial Cell Interactions

Hematogenous dissemination is a crucial step in infectious disease progression, causes most mortality due to bacterial infection, and is central to the spread of tick-borne Lyme disease pathogen Borreliella burgdorferi. A key step in dissemination is bacterial adhesion to endothelial cells lining blood vessels despite the shear stress generated by blood flow. B. burgdorferi strains that express different subsets of 30 known and predicted B. burgdorferi adhesins exhibit differences in tissue tropism in mice and humans. B. burgdorferi adhesins responsible for adhering to endothelia of various tissue beds remain largely uncharacterized. Like many other pathogens, B. burgdorferi targets fibronectin, a molecule that is part of the plasma and the extracellular matrix of endothelial cells. I investigated whether known B. burgdorferi fibronectin-binding adhesins could support interactions with different endothelial cell types under the fluid shear stress conditions of the vasculature. Using a flow chamber system and particle tracking, I investigated whether fibronectin-binding adhesins RevA, RevB, and BB0347 expressed in adhesion-attenuated B. burgdorferi promoted interactions with human umbilical vein, bladder, joint, and brain ECs. This approach identified potential tissue-specific fibronectin-binding vascular adhesins. Additional studies are needed to confirm whether these candidates act as vascular adhesins in vivo. This study has identified novel tissue-specific candidate vascular adhesins and will be important for understanding how and why the Lyme disease pathogen disseminates to different tissues.

Keywords: Bacteria
Dissemination
Endothelial cells
Fibronectin-binding adhesins
Lyme Disease
Vascular Interactions
Advisor: Moriarty, Tara
Hybrid Perovskite-on-silicon Integrated Electro-optic Modulators

Optical modulators are a key component in data center transceivers that are used for achieving electrical-to-optical signal conversion. Current silicon photonics modulators offer non-linear modulation responses, are difficult to fabricate, or have poor device lifetimes. This thesis attempts to incorporate solution-processable halide perovskites that exhibit the linear electro-optic effect onto silicon photonics chips for the purpose of creating efficient, high-speed, stable, and mass-manufacturable optical modulators. We present design architectures that are compatible with these materials, and set forth a post-processing fabrication procedure for realizing one specific design: the slot waveguide modulator. These devices are characterized in terms of their loss, low-speed and high-speed electro-optic performance, and stability. Discussion and ideas for future directions are also explored, and a benchmarking study using a commercially available electro-optic material is also presented. To our knowledge, this is the first integration of solution-processable halide perovskites onto a foundry fabricated active silicon photonics platform.

Keywords: Electro-optics
Halide perovskites
Integrated optics
Optical modulators
Silicon photonics
Advisor: Poon, Joyce K.S.
Heat Exchangers for Waste Heat Recovery

To reduce energy consumption and water heating requirements, the Ontario Building Code mandates every new residential building must install a drain water heat recovery unit to recover energy from drain water. A two-stage waste heat recovery unit is designed and tested with conformance to the Ontario Building Code. A novel leak detection system was implemented by measuring the electrical resistance of a coating. Thermal spray coating processes are used to create surfaces with enhanced performance. Flame spray and wire-arc spray produced two and three samples respectively. Each sample is tested to find the best heat transfer occurred with 0.125” diameter pillars, staggered, spaced 0.188” with enhanced surface area of 45.8% while increasing the convective heat transfer coefficient by 26.1% - 64.4% depending on the Reynolds number between 281 and 2745. The coatings are recommended to be utilized in a flat plate design with reduced complexity, size, and cost.

Keywords: DWHR
Heat exchanger
Thermal spray
Advisor: Chandra, Sanjeev
Sensitive Nanobiosensor using Upconverting Nanoparticles for the Detection of Reactive Oxygen Species

Upconversion nanoparticles (UCNPs) have many optical characteristics that make them moresuitable for bioanalytical applications when compared with traditional fluorophores and quantum dots including, emission by anti-Stokes, colloidal stability, and long lived luminescence lifetimes. In this thesis, a proof-of-design concept for UCNP-based detection of reactive oxygen species (ROS) is presented. Here, ROS sensing is achieved using a thioketal linker (Tkl), attached both to the surface of UCNPs, and to black hole quencher-3001 (BHQ-3001, the 3001 variety utilized to quench the 655 nm emission peak) molecules. Cleavage of Tkl occurs in the presence of ROS generated species. These species are generated in situ using hydrogen peroxide and horseradish peroxidase (HRP) enzyme and are assembled for the development of a turn-on biosensor using UCNPs and Tkl linker conjugated to amine-BHQ-3001.

Keywords: Multiplexing
Reactive Oxygen Species
Thioketal Linker
Upconversion
Advisor: Krull, Ulrich
Prosser, Scott
Biofluidics of Diarrhea in the Anorectum and its Implications for Global Health

Diarrhea is a symptom commonly reported in patients with diarrheal disease and inflammatory bowel disease. Doctors and public health practitioners rely on subjective, patient-reported data to diagnose, treat, and track these diseases. Theories and models of solid defecation exist, but models of diarrhea are limited, despite it being a common indicator of disease – especially for global health. This research identifies a pathway to objectively study diarrhea, through synthesis and adaptation of medical and engineering knowledge and analysis of anorectal compliance data to create two models of diarrheal defecation assuming homogeneous, Newtonian, fully developed, and steady. The two models provide useful insights on flow (velocity and flow rate) and its relationship with anorectal size and shape that may help guide future studies on diarrhea modelling. Next steps in the evolution of diarrhea modelling should focus on incorporating more complexities unique to diarrheal defecation such as its heterogeneous, Non-Newtonian, and unsteady behaviour.

Keywords: Anorectal Compliance
Biofluidic Modelling
Defecation
Diarrhea
Global Health
Advisor: Meyer, David
Work Integrated Learning and Career Management Competencies in International Students

There is evidence that international students in Canada struggle to succeed in the Canadian labor market post-graduation. Pre-graduation work experience has been identified as the single most important factor determining post-graduation career outcomes for international students. This study seeks to understand what factors influence the accumulation of pre-graduation work experience for international students, how career management competencies are developed, and if the development of career management competencies influences perceived employability. This study is based on 20 interviews with international students at a single research-intensive university in Ontario, Canada. This study finds that knowledge of the nuances of how to work as an international student in Canada, program support, and peer networks are highly influential in the accumulation of pre-graduation work experience. For students who participated in pre-graduation work experience, their participation directly impacted their decision making about remaining in Canada after graduation and perceived ability to succeed in the Canadian labor market.

Keywords: Career Management Competencies
Higher Education
International Students
Internationalization
Work Experience
Work Integrated Learning
Advisor: Buckner, Elizabeth
Wheelahan, Leesa
Exploring the Power of Experimental Evolution to Identify Dobzhansky-Muller Incompatibility Loci using Forward-time Simulations

Fitness reducing epistatic interactions referred to as Dobzhansky-Muller incompatibilities (DMIs) are responsible for the inviability and infertility prevalent in hybrid populations. As “evolutionary dead-ends,” these hybrid failures encourage reproductive isolation between two incipient species. Studies on hybrid genomes are therefore vital to understand the processes that underlie speciation events. My project aimed to determine the power of simulations to correctly identify genetic loci involved in reproductive isolation. Using SLiM, I created and evolved simulated hybrid populations with genomes containing user-defined DMIs. Biologically relevant parameters, such as recombination rates, selection coefficients, dominance effects, generation timepoints, and incompatibility types, differed among my simulations, allowing me to characterize the parameter spaces that resulted in high-powered estimates of DMI localization. My conclusions may act as a guide for evolve and re-sequence wet-lab experiments that aim to map real-world DMIs in Caenorhabditis hybrid populations.

Keywords: Computational Biology
Evolutionary Biology
Population Genetics
Power Analysis
Simulations
Speciation
Advisor: Cutter, Asher D
Leveraging Unsupervised Learning Methods to Improve Imagined Speech EEG-BCIs

A BCI is a direct communication pathway between the brain and an external device with the goal of providing communication for individuals with motor impairments. However, a considerable percentage of subjects cannot modulate their brain rhythms to communicate using BCI. From a machine learning standpoint, the instability of brain signals poses a critical challenge, which is the validity of the training data labels. Furthermore, the data generated in one’s mind cannot be directly evaluated. One potential solution is the inclusion of unsupervised methods in the learning processes of a BCI. This research proposes two methods based on unsupervised learning to relabel suspicious data, and to capture within class variations of data. These methods were tested in the development of imagined speech EEG-BCIs for 12 participants and significantly improved the classification performance for 7 of them. Future works are encouraged to use these methods to individualize the design of BCI protocols.

Keywords: brain-computer interface
electroencephalography
imagined speech
multiclassification
relabeling
unsupervised learning
Advisor: Chau, Tom
Hepatocellular Carcinoma Targeted Therapy by Lipoprotein-like Nanoparticle

Late-stage hepatocellular carcinoma (HCC) has no cure and currently, targeted therapy provides the most hope. This study investigated the suitability of porphyHDL nanoparticle carrying anti-Spalt-like transcription factor 4 (SALL4) siRNA. PorphyHDL is coated with apolipoprotein A-1 mimetic peptide, a ligand for scavenger receptor class B type 1 (SR-BI, SCARB1). We showed that SCARB1 and SALL4 gene expression are 1.3 fold higher in HCC tissue than adjacent tissue. SR-BI protein did not show a significant difference but SALL4 protein was overexpressed. In the liver, porphyHDL accumulated mostly in HCC cells and macrophages, followed by liver sinusoidal endothelial cells, and finally hepatic stellate cells. A fatty context in the liver - relevant in Western countries - increased SR-BI expression in adjacent tissue, but it increased porphyHDL specificity for HCC tissue versus adjacent tissue. In conclusion, this study suggests that porphyHDL loaded with anti-SALL4 siRNA can be useful as a targeted therapy for HCC.

Keywords: hepatocellular carcinoma
lipoprotein-like nanoparticle
liver cancer
scavenger receptor class B type 1 (SR-BI)
siRNA
Spalt-like transcription factor 4 (SALL4)
Advisor: Bhat, Mamatha
Zheng, Gang
Investigating Denervation Atrophy Through Prolonged Culture of Engineered Skeletal Muscle Tissues: The Good, the Bad, and the Ugly

Modern advancements in 3D skeletal muscle tissue engineering have provided an opportunity to develop a cell-based denervation culture model. The opening approach to establish denervation atrophy in vitro was through the prolonged culture of human immortalized 3D engineered skeletal muscle tissues. Myotube diameter, sarcomere organization, and calcium handling properties were assessed across a wide range of experimental endpoints to establish a purely myogenic tissue healthspan. A pattern of increasing muscle maturation for the first two weeks, then a slow decrease due to deterioration was observed. While evidence of denervation atrophy was detected, evidence of biomechanical instability was also implicated. Additionally, tissue variability and failure hindered results and prevented well drawn conclusions. Fibroblast co-cultures were constructed to improve tissue consistency, but experiments were unsuccessful. Thus, while this model holds promise, tissue variability and failure need to be reduced before further development and validation can be achieved.

Keywords: atrophy
culture model
denervation
skeletal muscle
tissue engineering
Advisor: Gilbert, Penney M
Development of a Flow Reactor Model for Carbon Nanoparticle Formation

This thesis presents a 1D model to investigate carbon nanoparticle synthesis in flow reactors. The first goal of this work is to improve upon an existing plug flow reactor code by implementing reactive dimerization and the Fuchs collision kernel to the particle formation submodels. Validation cases using discrete element methods and experiments from the literature benchmark the code performance. With these improvements, the predictions of mean particle properties are within 15% of experimental measurements. The second goal is to investigate the effects of radial diffusion on nanoparticle formation in laminar flow reactors by comparing the developed 1D code to a modified 2D laminar flow reactor model. Results show that gas-phase species exhibit plug flow, while particles tend to follow their individual streamlines. Furthermore, by utilizing the radial integration method, the 1D code predicts the gas-phase species and particles with accuracies similar to the 2D model at lower computational costs.

Advisor: Thomson, Murray
Identifying Protocadherin Gamma-dependent Signaling Pathways that Regulate Interneuron Survival

Developmental programmed cell death (PCD) is critical for establishing balanced ratios of excitatory and inhibitory neurons, but the underlying mechanisms remain poorly understood. A group of neuronal cell-surface receptors, called Protocadherin gammas (Pcdhγs), are essential for promoting inhibitory interneuron survival during PCD. In this study, I analyzed three candidate factors - ILK, DYRK1A, and PTEN – and their roles in the downstream regulation of Pcdhγ-mediated interneuron survival in the mouse neocortex and retina. I found that Pcdhγ and DYRK1A may function together to regulate interneuron number. Additionally, Pcdhγ and PTEN signal together to regulate interneuron survival during PCD in the retina. Interestingly, elevated AKT signaling alone is not sufficient for maintaining interneuron survival in the absence of Pcdhγs. By assessing candidate regulators of interneuron number and by characterizing genetic interactions between Pcdhγ and PTEN, this study links PTEN activity to Pcdhγ-mediated interneuron survival signaling during neurodevelopmental PCD in the retina.

Keywords: Cortex
GABAergic interneuron
Programmed cell death
Protocadherins
Retina
Advisor: Lefebvre, Julie L
Challenges, Issues and Opportunities in Household Travel Surveys

Urban travel demand analysis efforts predominantly use household travel surveys for data supports. However, the data collection method is facing several challenges. First, online household travel surveys have been suffering declining completion rates, raising data quality issues. Second, the practice of large-scale household travel surveys has been plagued by proxy biases and under-representations for specific sub-groups of populations for decades. The thesis examines the causality and implications of high survey incompletion rates in online travel surveys and makes recommendations for future practice. The thesis also proposes a hybrid data fusion approach to reduce proxy-biases and under-representation in large-scale household travel survey datasets. Besides challenges, online household travel surveys bring unprecedented opportunities due to their operational ease compared to traditional telephone-based surveys. The thesis also presents a case study of an online household travel survey conducted to facilitate policymaking during the COVID-19 pandemic.

Keywords: Transportation Planning
Travel Demand Analysis
Travel Survey Method
Advisor: Nurul Habib, Khandker
Miller, Eric J.
Identifying Emotions Associated with the Mental States of Understanding

There is a lack of clarity regarding the fundamental nature of academic emotions as the relationship between academic emotions and understanding has not been investigated at the micro level. This study investigated the emotion profiles of cognitive disequilibrium, intrigue, engagement, achievement, contentment, and understanding to gain clarity regarding how academic emotions shape the process of working towards an understanding at the micro level. The participants were 189 MTurk workers (Mage = 35.35, SD=8.6). Participants associated emotions with these six states using the Mental States of Understanding and Emotions Questionnaire (MSE). Distinct emotion profiles were associated with each state and there were varying degrees of similarity between them. The results suggest that academic emotions proximally and distally shape understanding at the micro level in a comprehensive and cohesive manner. Future studies should elucidate the transitions between the six states as learners work towards an understanding in real time.

Advisor: Woodruff, Earl
Data-driven Inpatient Bed Demand Forecasting Model for Surge Mitigation

Hospitals have been experiencing more frequent medical surges, the state at which inpatient beds are near or at full capacity, as both healthcare expenditure and demand have been increasing. Currently, there is no surge prediction tool designed for the short-term horizon, resulting in a short lead time to prepare for any upcoming bed demand. This study proposes a data-driven bed demand forecasting model composed of Long Short-Term Memory network, Gamma mixture model, and Discrete Event Simulation model, that intakes only high-level patient visit information and other exogenous variables, such as public holiday status and day of the week, to forecast inpatient admissions, estimate their length of stay, and simulate the upcoming bed usage to identify a potential surge at a specific program level. Given the forecast, the hospital can proactively plan and allocate its resources and reduce the likelihood of poor inpatient bed utilization.

Keywords: Forecasting Model
Inpatient Admission
LSTM
Patient Flow
Simulation
Surge Mitigation
Advisor: Carter, Michael W.
A 3D Cadaveric Study on the Innervation to the Cervical Zygapophysial Joints: Implications for Image-guided Radiofrequency Ablation Procedure

Image-guided nerve block (NB) and radiofrequency ablation (RFA) of the medial branches of cervical posterior rami are recommended non-opioid intervention options for chronic cervical zygapophysial joint (CZJ) pain. Although precise 3D knowledge of the course of the innervation to the CZJs is required for these procedures, no 3D studies investigating the articular branches to the CZJs were found in the literature. The purpose of this cadaveric study was to document in 3D the course of the sensory innervation to the C2/C3-C6/C7 zygapophysial joints relative to bony/soft tissue landmarks using serial dissection, digitization, and 3D modelling. The number of articular branches, site of origin, and point of entry into the CZJ capsules relative to bony/soft tissue landmarks were defined in 3D. The result of this thesis provides a novel evidence-based foundation for developing new image-guided NB/RFA treatment protocols.

Keywords: anatomy
cervical spine
cervical zygapophysial joint innervation
imaging
nerve block
Radiofrequency ablation
Advisor: Agur, Anne MR
Completion of a Phase 2 Outpatient Cardiac Rehabilitation Program following Transcatheter Aortic Valve Implantation or Surgical Aortic Valve Replacement

Background: Transcatheter aortic valve implantation (TAVI) patients are underrepresented in outpatient cardiac rehabilitation (OCR) and the effectiveness and completion of a 24-week OCR program comparing TAVI with surgical aortic valve replacement (sAVR) patients has yet to be investigated. Objectives: To compare 1) the effectiveness of OCR, 2) program completion rates between TAVI and sAVR patients, and 3) examine predictors of program completion. Methods: A retrospective database review was conducted. Results: OCR was effective in significantly improving the peak oxygen uptake of TAVI (p

Keywords: Outpatient Cardiac Rehabilitation
Peak Oxygen Uptake
Program Completion
Surgical Aortic Valve Replacement
Transcatheter Aortic Valve Implantation
Advisor: Colella, Tracey J. F.
Brooks, Dina