VictorJuiz/thesis huggingface dataset:
Resting-state fMRI Activity within the Semantic Network Associated with Changes in Verbal Fluency after Anterior Temporal Lobe Resection
Keywords: fMRI
Matrix Similarity
Semantic memory
Temporal Lobe Epilepsy

The aim of this study was to examine the impact of disruption of the semantic network, including the ATL, on performance in fluency tasks considered to be differentially dependent on the integrity of this amodal hub. We studied 17 patients who underwent surgical resection of the left ATL to improve seizures. We collected pre-surgical resting-state fMRI data as well as pre- and post-surgery performance on verbal fluency tests. A correlation value representing the similarity between the network resting-state connectivity pattern of each patient and that of a healthy control template was calculated. We found a significant positive correlation between this matrix similarity score and pre- to post-surgical change in both unique and general semantic fluencies, indicating that a more ‘normative’ network is protective. The connections driving that effect were those outside the to-be-resected ATL. Overall, our findings indicate that network integrity is key in predicting post-operative changes in semantic processing.
Novel Porous Transport Layers with Through Pores for Polymer Electrolyte Membrane Electrolyzers
Keywords: Mass transport losses
PEM electrolyzer
Porous transport layer
Synchrtron X-ray radiography

Development of cost-effective porous transport layers (PTLs) for polymer electrolyte membrane (PEM) electrolyzers is crucial for the implementation of clean energy systems. In this thesis, novel PTLs with through pores have been investigated. Limited mass transport in the in-plane direction was observed in through pore PTLs, using in operando synchrotron X-ray radiograph. Furthermore, the limited in-plane mass transport led to dehydration of the catalyst layer (CL). Therefore, the placement of through pores play a critical role in the performance of PEM electrolyzers. Next, through pore PTLs consisting of woven meshes were studied. The contact resistance between the woven mesh PTL and the CL dominated performance losses, and smaller pore sizes improved the contact resistance. Stacking meshes with different pore sizes resulted in inhomogeneous compression of the CL, significantly degrading the PEM electrolyzer performance. The results from this thesis contribute to the development of cost-effective PTLs for next generation PEM electrolyzers.
A Scoping Review: Comparing Federal Health Policy and the Associated Impacts on Access to Care in First Nations and American Indians/Alaska Natives Communities
Keywords: Access to Care
American Indians/Alaska Natives
Canada
First Nations
Health Policy
United States

Canada and the United States each have a federal responsibility to deliver health services in First Nations (FNs) and American Indian/Alaska Natives (AIANs) communities. Yet, inequitable access to healthcare continues to disproportionately impact both communities. Little research has compared federal health policies between the two countries to see how they may help to explain the current state of healthcare access. This study aims to fill this gap. To do so, I completed a scoping review and three validation interviews with Indigenous health policy experts. The findings suggest that Canada exercises a greater use of informative policy instruments, compared to regulatory instruments in the United States. Policies in the two countries were frequently described as impacting similar dimensions of access. This study offers perspective on key policies involved in healthcare access, the contextual differences between the two countries Indigenous health policy making practices, and may inform future policy analysis.
Functional Genomic Screening of Nematocida parisii Host-exposed Proteins
Keywords: Functional Genomics
Microsporidia
Yeast

Microsporidia are a divergent group of obligate, intracellular pathogens that are relatively poorly understood. The Caenorhabditis elegans intestinal infecting Nematocida parisii, has been shown to secrete a diverse arsenal of proteins to their cells upon infection, labelled “host-exposed” proteins. These secreted proteins may be serving roles as effector proteins, and the model organism Saccharomyces cerevisiae has proven to be a reliable system for the study of bacterial effectors. This uses yeast to study microsporidian host-exposed proteins. I have generated a pipeline to clone N. parisii genes into yeast expression vectors and demonstrated reliability by generating a gene set of 97 N. parisii host-exposed genes along with additional controls. Screening this gene collection identified 23 toxic genes, demonstrating that this strategy may help further understanding of microsporidian infection biology by identifying novel microsporidian effector proteins and learning more about the rules of these proteins and their expression in yeast.
Deep Learning-based Fault Diagnosis in Transmission Lines via Long Short Term Memory Networks
Keywords: Deep Learning
Fault Classification
Fault Diagnosis
Long Short Term Memory Networks
Smart Grid

In electrical power systems, transmission lines are responsible for transferring power across the grid. However, faults in these lines are abnormal conditions that can destabilize the transmission system if sustained longer. To diagnose the faults, IEC61850 based digital substations provide the sampled value measurements in the substation. In addition to existing model-based techniques to diagnose the fault, machine learning techniques are explored in the literature. In this thesis, we present a novel Long Short Term Memory (LSTM) based fault classifier using current and voltage measurements as the input. Compared with deep learning algorithms proposed in the literature i.e. RNN and SVM, the proposed classifier provide improved performance in the classification of faults, tested on data obtained from a PSRC D6 benchmark testbed. The performance of the classifier is explained with the evaluation metrics i.e. test accuracy, precision, recall, F1 score and confusion matrix to show the classification performance.
An Empirical Investigation of the Role of Population Health in the Aggregate Production Function: A Multi-country Study
Keywords: Aggregate
Health capital
Life expectancy
Production function
Solow

Adopting an aggregate production function approach, we investigate the role of population health on output per worker. A panel fixed-effects estimation is used to conduct the primary analysis and we employ the use of subsets to investigate the relationship at various life expectancy thresholds. Our results indicate that health capital, proxied by life expectancy at birth, has a U-shaped relationship with output per worker. In the subset analysis, we find that in shorter-lived countries, improvements to life expectancy at birth have a positive and significant relationship with output per worker. In longer-lived countries, improvements to life expectancy at birth have an insignificant impact on output per worker.
Design of Mitochondrial Targeting Peptide-based SIRT1 Activators
Keywords: mitochondria
sirtuin

Mitochondria, colloquially known as “the powerhouse of the cell”, play important roles not only energy production, but also in processes critical for cellular fate such as cell death, differentiation, signaling, metabolic homeostasis, and innate immunity. Due to their many functions in the cell, mitochondria have been linked to a variety of human illnesses such as diabetes, cancer, and neurodegenerative diseases. The target protein for this work was SIRT1, known to be involved in mitochondrial biogenesis. A mitochondrial targeted peptide was attached to known SIRT1 activators SRT1720 and SRT1460 in an attempt to increase mitochondrial biogenesis. Small improvements to mitochondrial health markers were seen upon treatment of these conjugated sirtuin activators, but more work is needed to confirm their efficacy.
Multi-period Portfolio Optimization with Investor Views under Regime Switching
Keywords: Black Litterman
Dynamic Asset Allocation
Hidden Markov Model
Investment Views
Multi-Period Portfolio Optimization
Receding Horizon

We propose a novel multi-period trading model that allows portfolio managers to perform optimal portfolio allocation while incorporating their interpretable investment views. This model's significant advantage is its incorporation of the latest asset return regimes to quantitatively solve managers' question: how certain should one be that a given investment view is occurring? First, we describe a framework for multi-period portfolio allocation formulated as a convex optimization problem that trades off expected return, risk and transaction costs. Second, we use the Black-Litterman model to combine investment views specified in a simple linear combination based format with the market portfolio. A data-driven method to adjust the confidence in the manager's views by comparing them to dynamically updated regime-switching forecasts is proposed. Our contribution is to incorporate both multi-period trading and interpretable investment views into one efficient framework and offer a novel method of using regime-switching to determine each view's confidence.
Combined Healthy Lifestyle Behaviors: Metabolomic Effects and Implications for Type 2 Diabetes Prevention
Keywords: healthy lifestyle
healthy lifestyle behaviour
Insulin resistance atherosclerosis study
metabolomic signature
multiethnic cohort
type 2 diabetes

A combination of healthy lifestyle behaviors has been consistently associated with reduced risk of type 2 diabetes mellitus (T2DM) although these associations in a multiethnic cohort remain unknown. The aims of this research were to: 1) systematically review published literature on the metabolomic profile of combined healthy lifestyle behaviors and, 2) assess the associations between combined healthy lifestyle behaviors and incident T2DM in a multiethnic cohort. Three databases were searched for studies outlining the metabolomic profile of combined healthy lifestyle behaviors. Multivariable logistic regressions explored their associations with incident T2DM in a multiethnic cohort. Results showed: 1) a positive association between combined healthy lifestyle behaviors and beneficial fatty acids and phosphocreatine as well as inverse associations with TMAO and other biomarkers; and 2) a significant association (OR=0.85, CI: 0.75-0.96, p=0.009) with incident T2DM. Regular adoption of multiple healthy lifestyle behaviors leads to beneficial metabolomic changes and lower risk of T2DM.
Adeno-associated Viral Delivery of Neurod1 to GFAP-expressing Cells of the Medial Prefrontal Cortex Post-stroke Reveals Ectopic Expression in Cortical Neurons
Keywords: Medial Prefrontal Cortex
Neurod1
Neurons
Regeneration
Reprogramming
Stem Cells

Stroke is a leading cause of death and disability, often leaving survivors with motor and cognitive impairments. The delivery of neurogenic transcriptions factors (TFs) has been shown to induce astrocyte-to-neuron conversion in vitro and in vivo. Thus, we examined the potential of direct cellular reprogramming to treat cognitive impairments in a subacute model of stroke in the medial prefrontal cortex (mPFC) in Cre-conditional reporter mice. AAV5-GFAP::Cre or AAV5-GFAP::Neurod1Cre (pro-neural TF) was delivered to the perilesional cortex. We observed the unpredicted expression of Cre in neurons post-stroke in the mPFC of AAV5-GFAP::Cre injected brains, unlike motor cortex observations. These regional differences were consistent with the presence of GFAP mRNA in mPFC neurons. We observed cellular reprogramming 21 days following ectopic Neurod1 expression, which was sufficient to enhance cognitive recovery. Overall, this study demonstrated the impact of astrocyte-to-neuron reprogramming on cognitive behaviour following stroke and highlighted regional differences in this therapeutic approach.
Contemplating Infrastructure: An Ethnographic Study of the University of Toronto Faculty of Information Inforum’s iRelax Mindfulness Resource Area
Keywords: academic libraries
contemplative practice
ethnography
infrastructure
mindfulness meditation
yoga

Created in 2016, the iRelax area is an innovative meditation and yoga resource hub situated within the University of Toronto Faculty of Information’s Inforum. Comprised of approximately fifty interconnected digital, physical, and textual resources, the iRelax area possesses a distinctly open and visible spatial profile intended to promote open conversations about mental health. This ethnographic case study of the iRelax area examines the initiative’s aesthetic, informational, organizational, and spatial properties, as well as individuals’ encounters and interactions therewith. The iRelax area’s associated Mindful Moments program, or free, guided meditation sessions offered within the learning commons one day per week, is also examined. In order to develop a detailed understanding of the relationship between the iRelax area and this program, the study’s design was broadened to include consideration of contemplative inquiry as a complement to ethnography. The study casts the iRelax area and its associated Mindful Moments program as contemplative infrastructure.
The Associations between Hearing, Cognition and Mobility among Healthy Older Adults
Keywords: Cognition
Healthy Older Adults
Hearing
Mobility
Objective Assessments
Subjective Assessments

Aging is often associated with declines in hearing, cognitive and motor functioning. Evidence suggests that there are declines between hearing and cognition, cognition and mobility, and hearing and mobility. However, previous studies typically assess these abilities independently of each other (rather than holistically), focus on impairments (rather than age-normative declines) and use objective (rather than subjective) assessments. Therefore, this study aimed to fill these gaps by examining the hearing-cognition-mobility link within the same healthy older adult sample using both objective and subjective assessments; that is, in those with healthy cognitive and mobility functioning across a spectrum of hearing abilities. We found that better subjective hearing predicted better subjective cognition, (2) poorer subjective cognition predicted better objective mobility, and (3) better subjective hearing predicted both poorer objective mobility and better subjective mobility. Taken together, interventions aimed at cognitive training or falls-risk mitigation, should consider the intersection of hearing, cognition, and mobility.
Intraspecific Variation in Regulation of Water Status and Cold Acclimation in Interior and Coastal Douglas-fir in Response to Simulated Warmer and Drier Climate
Keywords: autumn cold acclimation
climate change
Douglas-fir
drought
intraspecific variation
xylem

Climate change in northern forests is causing increased water stress during summer droughts and potentially increased frost vulnerability following warmer autumns. Physiological responses to changing climate may vary among populations of tree species with broad ranges, such as Douglas-fir (Pseudotsuga menziesii). We aimed to characterize intraspecific variation in the responses of interior and coastal Douglas-fir to summer drought and autumn warming. We assessed photosynthesis, water use efficiency, xylem function, and freezing tolerance in seedlings under controlled conditions. Interior populations exhibited hydraulically safer but less efficient xylem whereas coastal populations exhibited more hydraulically efficient but less safe xylem. Differences in photosynthesis were minimal but suggested lower drought tolerance in the most coastal population. Autumn warming delayed downregulation of photosynthesis, however this did not impair development of freezing tolerance. This research will help determine which tree populations are best adapted to future warmer and dryer climates and thus improve forest regeneration efforts.
Evidence-based Water Loss Management: A Novel Approach to Data Collection and Performance Benchmarking in Ontario, Canada
Keywords: District Metered Area
Monte Carlo Analysis
Performance Benchmarking
Pressure-Leakage Response
Water Distribution System Leakage
Water-Energy Nexus

It is well understood that leakage in water distribution systems (WDSs) yields adverse financial and environmental impacts. Consequently, effective practices to manage and control leakage are becoming increasingly desired. Existing methodologies, however, have emerged mostly from the European context, giving rise to various limitations and forms of uncertainty when employed in North America. Accordingly, this research promotes field-based practices to enable the assessment of actual system performance, thereby mitigating the potential (and often appreciable) impact of such uncertainties. Central to this work is the development and deployment of a mobile testing unit to monitor flows, with and without pressure reduction, into temporarily configured district metered areas (DMAs). Results from an Ontario-wide testing program have informed various benchmarking metrics from which DMA performance can be objectively quantified. The research targets municipalities in their decision-making efforts through the provision of insightful information to better manage both system leakage and pressure.
Molecular Subtyping to Stratify the Treatment of Muscle-invasive Bladder Cancer: A Cost-effectiveness Analysis
Keywords: Bladder cancer
Cost
Decision analysis
Neoadjuvant chemotherapy

Introduction: The standard treatment for muscle invasive bladder cancer (MIBC) is neoadjuvant chemotherapy (NAC) followed by radical cystectomy but response to NAC is unpredictable. Molecular subtypes allow for an improved ability to select a tailored treatment course. Our study aims to assess the cost-effectiveness of molecular subtyping. Methods: A Markov microsimulation model was developed comparing three strategies: NAC at current usage rates, universal NAC usage, and molecular subtype-directed care. Primary outcomes were quality-adjusted life years (QALYs), cost, and the incremental cost-effectiveness ratio (ICER). Results: The predicted QALYs were 8.34, 8.73, and 9.14 with costs of $62,478, $76,962, and $62,579 for NAC at current usage rates, universal NAC usage, and subtype-directed care. When comparing subtype-directed care to current rates of NAC usage the ICER was $127/QALY. Conclusion: In patients with MIBC a subtype-directed approach to the administration of NAC can result in greater QALYs and be cost-effective.
Cluster-based Index Tracking Via QUBO and Digital Annealing
Keywords: Digital Annealing
Graph Clustering
Index Tracking
Market Graph
Mathematical Programming
Portfolio Optimization

The cardinality constrained index-tracking problem seeks to find a combination of financial assets to replicate the return of a broad market index while using only a small subset of the asset universe. However, finding this combination of assets is NP-hard. In this thesis, we show the computational efficacy of solving a quadratic unconstrained binary optimization (QUBO) problem using purpose-built hardware Digital Annealer. We express an intra-cluster distance minimization problem as a QUBO problem and examine the computational performance between Digital Annealer and a commercial solver Gurobi running on conventional hardware. Moreover, we develop a new framework to solve the cardinality constrained index-tracking problem using the quadratic k-medoids clustering method on a market graph. To circumvent the nature of NP-hardness, we use the penalty method to formulate the problem as a QUBO problem, allowing us to utilize purpose-built hardware to solve the problem.
H2S as a Potential O2 Sensor in C. picta Cerebral Cortex
Keywords: anoxia
C. picta
fluorescence
H2S
hydrogen sulfide
turtle

The freshwater Western painted turtle, Chrysemys picta, is one of the most anoxia-tolerant vertebrates able to withstand months of anoxic conditions under ice-covered lakes. The turtle demonstrates remarkable recovery upon reoxygenation without sustaining organ damage associated with oxidative stress. It owes its winter survival to metabolic suppression, enhanced glycogen stores and proton buffering. Our recent work of pyramidal mitochondrial membrane potential depolarization and mitochondrial Ca2+ release has rendered the mitochondria a possible oxygen sensor in turtle neurons. However, the initial signaling molecule remains unknown. We speculate hydrogen sulfide (H2S) to act as a molecular oxygen sensor in neurons by its action on Ca2+ channels during anoxic stress. I have demonstrated an anoxia-dependent H2S increase (50%), and a H2S-induced Ca2+ increase (~5%) directly via exogenous Na2S and indirectly via inhibition of the H2S synthesizing enzymes. Thus, we postulate H2S to have retained its primordial significance by adopting a role in O2 sensing in oxygen deprived tissues.
The Study on Cell Nucleation and Cell Growth Mechanisms and Behaviors in Multilayered Alternating Film/Foam Structures
Keywords: Material science
Multilayered structures
Polymer manufacturing

This thesis presents the fundamental and experimental investigation of cell nucleation and growth mechanisms in advanced Micro-/Nano-Layered (MNL) polymeric structures with alternating film and foam layers. Novel strategies to optimize MNL structures are also developed. It is found that the final cell morphologies in MNL systems are governed by the synergy of two categories of parameters: morphological parameters, i.e., layer thicknesses and interface densities; and material parameters, i.e., material stiffness and material compatibility. The presence of adjacent film layers can significantly increase cell densities and decrease cell sizes through two mechanisms: promoting heterogeneous cell nucleation and preventing cell deterioration. Stiffer and more compatible film layers produced higher cell densities by further boosting these two mechanisms. Moreover, as a stiffness-enhancing strategy, the crystallization of PC layers was successfully achieved for the first time in MNL structures, resulting in more pronounced optimizations in cell morphologies.
Reimagining Informal Place-based Learning: An Exploration through Narratives of Scarborough Residents
Keywords: adult education
educational leadership
informal learning
narrative inquiry
place-based learning
Scarborough

Scarborough, a region marred by its representation as a “dangerous” region has arguably left residents with internalized otherness, along with complicated understandings of themselves and their surroundings. Using narrative inquiry, this qualitative study explores how Scarborough residents conceptualize informal learning in connection to place. Interviews were conducted with six residents from the Malvern and Kingston-Galloway/Orton Park (KGO) neighbourhoods to better understand their lived experiences and interactions with informal learning. Critical pedagogy of place and critical consciousness are the theories informing the conceptual framework and guiding this study. Emerging from the data are four themes: shared understandings of community, barriers to learning and opportunity, meaningful informal learning experiences and representative and reciprocal relationships. In using place as a guiding framework for inquiry, residents describe the creation of informal spaces of gathering and storytelling as tools in countering the hegemonic narratives of Scarborough and its many communities.