VictorJuiz/thesis huggingface dataset:
Characterizing Neuropathic Pain in the Naked Mole-Rat (Heterocephalus glaber)
Keywords: naked mole-rat
neuropathic pain
nociception
rodent behavior
social status
TRP receptors

The nociceptive system of the African naked mole-rat (Heterocephalus glaber) contains unique adaptations that make the species insensitive to skin pain from some chemical stimuli. Sensitivity to thermal and mechanical stimuli are hallmark symptoms of chronic pain following nerve injury. Upon damage, a cascade of molecular signals is released and contribute to chronic pain. To determine whether naked mole-rats develop long-lasting sensitivity, I adapted the spared nerve injury rodent model and applied the model to subordinate males and females of soldier and worker status. I then measured behavioral responses to mild and strong mechanical stimuli and a mild cold stimulus. Hypersensitivity to both mild and strong mechanical stimuli were comparable between naked mole-rats and mice following nerve injury. Unlike mice, naked mole-rats showed no reaction to mild cold after nerve injury. This non-response to mild cold could arise from unusual connectivity or atypical receptor expression or function. Le système nociceptif du rat-taupe africain nu (Heterocephalus glaber) contient des adaptations uniques qui rendent l’espèce insensible aux douleurs de la peau causées par certains stimuli chimiques. La sensibilité aux stimuli thermiques et mécaniques est un symptôme caractéristique de la douleur chronique consécutive à une lésion nerveuse. Pour déterminer si les rats-taupes nus développent une sensibilité durable, j'ai adapté le modèle de rongeur lésé au nerf épargné et appliqué le modèle aux subordonnés mâles et femelles ayant le statut de soldat et de travailleur. J'ai ensuite mesuré les réponses comportementales à des stimuli mécaniques légers et forts et à un stimulus froid léger. L'hypersensibilité à des stimuli mécaniques légers et puissants était comparable chez les rats-taupes nus et les souris après une lésion nerveuse. Contrairement aux souris, les rats-taupes nus ne présentaient aucune réaction au froid léger après une lésion nerveuse.
Striving to Do No Harm and yet Respect Patient Autonomy: Ontario Plastic Surgeons’ Perspectives of the Consultation for Breast Reconstruction with Women Who Have Early Stage Breast Cancer
Keywords: Breast Reconstruction
Contralateral Prophylactic Mastectomy
Early Stage Breast Cancer
Ontario
Plastic Surgeon
Treatment Decision Making

Background: The rate of contralateral prophylactic mastectomy (CPM) has doubled over the previous decade in women with early-stage breast cancer. Despite the strong association between CPM and breast reconstruction, little is known about the clinical encounter between patients and plastic surgeons. Purpose: A qualitative study aligned with the constructivist paradigm was conducted to understand how plastic surgeons describe their roles in the decision-making process through their consultations with women who have early-stage breast cancer. Methods: Semi-structured interviews were conducted with Ontario plastic surgeons. An inductive and interpretive thematic approach was used to analyze the data. The four principles of biomedical ethics were used as the conceptual lens to interpret the findings. Results: Four themes were identified: maintaining non-maleficence, supporting patient autonomy, delivering (un)equal healthcare, and providing care to enhance well-being. Conclusions: Plastic surgeons must balance competing responsibilities to do no harm and support a patient’s right to autonomous healthcare decisions.
Aeroacoustic Noise Prediction and Acoustic Optimization of Mufflers
Keywords: aeroacoustics
muffler
optimization
plug flow muffler
simulation-based optimization
tandem cylinder

Noise control of large diesel and natural gas generators is achieved through industrial mufflers. Design of such mufflers relies heavily on general guidelines. But these guidelines are not suitable for complex mufflers; instead, automated optimization provides an effective means of design. Optimization of a plug flow muffler (PFM) is conducted in this work with two different approaches: 1) a relatively simple gradient-descent algorithm (L-BFGS-B) maximizing the transmission loss of the PFM, and 2) a multi-objective (transmission loss and pressure drop) simulation-based optimization using the Efficient Global Optimization (EGO) algorithm. The EGO algorithm is shown to be well suited for muffler optimization, performing vastly better than the commonly used NSGA-II algorithm. In addition, the initial steps towards the prediction of aeroacoustic noise (self-noise) in mufflers is accomplished through the CFD simulation of the tandem cylinder benchmark experiment.
The Role of the Physician in the Reach and Adoption of Online Health Resources - A Qualitative Study of the Perspectives of Patients and Health Care Providers
Keywords: Adoption
Implementation
Physician Role
Reach
RE-AIM

Introduction: Prostate cancer (PCa) patients are living longer with side effects of their treatments, which are often debilitating. Online health resources (OHRs) could provide PCa patients with health information and support needs they often lack. Purpose: To understand the contextual aspects of reach and adoption within the RE-AIM framework, and how they inter-relate through the role of the physician within the context of online health resources. Methods: Secondary qualitative analysis using data collected to inform the design of an interactive OHR. Inductive/deductive hybrid analysis was used. Results: Findings yielded three main categories of use and uptake of online health resources by patients: reach, patient uptake of OHRs, and physician uptake of OHRs. Conclusions: By contributing to both reach and adoption, physicians can increase patients’ use of OHRs. These findings can improve the implementation OHRs for patients, fulfilling the need for information that PCa survivors have and increasing their quality of life.
Impact of Low Coagulant Dosages on Protein Fouling of Ultrafiltration Membranes
Keywords: coagulation
fouling mitigation
protein fouling
ultrafiltration

Ultrafiltration fouling in drinking water treatment has been primarily attributed to the biopolymer fraction (e.g., proteins) of organic matter in source waters. This bench-scale study examined the use of coagulation to mitigate fouling in three model protein solutions. Similar to results from studies conducted with natural waters, a low coagulant dose (2 µM Al) was identified to significantly reduce membrane fouling relative to zero coagulant addition for two proteins (BSA and ovalbumin). It is hypothesized that the low dosages alter the surface hydrophobicity of proteins in both the bulk solution and fouling layer, resulting in weakened intermolecular interactions, reducing fouling. The impacts of applying coagulation only during the initial stages of a permeation cycle (phased coagulation) on membrane fouling were investigated at pilot-scale. Coagulant application during the first half of the cycle resulted in fouling rates similar to that of continuous addition, which could translate to significant cost savings.
Impact of the Model of Long-term Follow-up Care on Adherence to Guideline Recommended Surveillance Among Survivors of Adolescent and Young Adult Cancers
Keywords: AYA
Survivorship

We explored the predictors of LTFU care received by a population-based cohort of survivors and the impact of care on adherence to recommended surveillance. Five-year survivors were identified from a provincial administrative health database of patient’s aged 15-20.9years at diagnosis between 1992-2010. We defined four models of LTFU care: specialized survivor clinic; oncology clinic; primary care physician; no care. Poisson regression models examined attendance rates, while logistic regression models assessed guideline adherence to surveillance. For 1,574 survivors, the risk of receiving no care was highest in males and increased 7% per year of follow-up. Among those eligible for specialized survivor clinics, greater attendance was observed in females and those living closer to a clinic. Female survivors at risk for breast cancer were 2.9 times more likely to receive annual mammograms if followed at a specialized clinic. Identifying accessible care models that maximize surveillance adherence must be a key research focus.
The Toxicological Impact of Wastewaters on Drinking Waters Sources
Keywords: De Facto Reuse
Genotoxicity
SOS Chromotest
Surface Water
THMs
Wastewater

Surface waters may contain wastewater effluent associated with de facto reuse which can impact their toxicological properties both before and after treatment. This study examined the genotoxic response of three surface waters containing a range of wastewater effluent (5%, 10%, and 25% by volume). The SOS ChromotestTM was used to assay the genotoxicity of both chlorinated and unchlorinated mixtures whereas toxicity index model based on the CHO comet assay was used to predict the contribution of trihalomethanes (THM), haloacetonitriles (HAN), and halonitromethanes (HNM) to overall genotoxicity of chlorinated mixtures. Wastewaters were generally genotoxic whereas raw and chlorinated surface waters were not. Mixtures containing 5% and 10% wastewater generally had similar responses to chlorinated surface waters alone; significant effects were more common at higher ratios (≥ 25%). SOS genotoxicity correlated strongly with predicted genotoxicity, DOC, and THM concentrations, suggesting that THMs may potentially serve as surrogates for toxic disinfection by-products (DBPs).
Nash Equilibrium Seeking with Output Regulation
Keywords: Control Theory
Game Theory
Multi-Agent Systems
Nash Equilibrium
Nonlinear Control Theory
Output Regulation

We consider the problem of Nash equilibrium seeking (NE) for games with agents subject to exogenous signals. Using the framework of output regulation, we design dynamic gradient play feedback control laws that incorporate internal models of the exogenous signals. We start by considering linear agents with linear exosignals under full-information. We incorporate a Laplacian-based consensus algorithm to handle the case of partial information. Finally, we extend this framework to handle a class of nonlinear agents subject to nonlinear exosignals.
Enstrophy Transport in Premixed Swirl Flames
Keywords: Enstrophy transport
Micro-scale turbulence
Premixed combustion
Swirl flames

Reynolds-averaged enstrophy transport budgets are measured in turbulent swirl flames using micro-tomographic particle image velocimetry (µ-TPIV) and CH2O planar laser induced fluorescence (PLIF) across Ka = 11-45. The combined contributions of baroclinic torque and dissipation to enstrophy transport are evaluated by subtracting the vortex-stretching and dilatation terms from the Lagrangian derivatives. Enstrophy production through baroclinic torque dominated over dissipation towards the product sides of the flame brushes. Enstrophy budgets, conditioned on mean progress-variable and spatial coordinates, have shown that the magnitude of baroclinic torque increases with bulk flow velocity. A conservative estimate of the relative significance of baroclinic torque to vortex-stretching was found to be constant. In contrast to DNS of flames in HIT, the significance of baroclinic torque relative to vortex-stretching remained constant with bulk flow velocity. The observed flame-scale turbulence generation towards the combustion products has implications both for turbulence and combustion closure models.
Impact of the Innate Immune Checkpoint Inhibitor SIRPα-Fc on Immune Function
Keywords: CD47
Immunotherapy
SIRPa
SIRPα
SIRPα-Fc

Signal regulatory protein α (SIRPα) is an inhibitory receptor expressed on myeloid cells that functions as a “healthy self-recognition” receptor by engagement with its ubiquitously expressed cell-surface ligand CD47. Disruption of the interaction between CD47 on primary human leukemia cells and SIRP on host macrophages with a decoy receptor SIRPα-Fc provokes robust leukemia cell phagocytosis and clearance. Because CD47 is widely expressed, we asked whether SIRPα-Fc administration may also impact the frequency and function of normal immune cells. To test this idea, NOD mice were treated with SIRPα-Fc and subjected to immunophenotypic, serum cytokine and complete blood cell count analyses. Modest alterations in dendritic cell (DC) populations and reduced levels of several inflammatory cytokines and platelets were observed in SIRPα-Fc compared to control Fc fusion protein-treated mice. SIRPα-Fc administration did not affect T cell activation or proliferation in a DC:T cell co-culture system suggesting safe use as an immunotherapy.
The Learning Curve and Annual Procedure Volume Standards for Optimum Outcomes of Transcatheter Aortic Valve Replacement: Findings from an International Registry
Keywords: Learning Curve
Minimal Annual Volumes
Transcatheter aortic valve replacement

Transcatheter aortic valve replacement (TAVR) is a technically complex procedure. Despite increasing use of TAVR across institutions, incomplete knowledge exists to describe the learning curve and minimum annual volumes for this procedure. We hypothesize that TAVR has a prolonged learning curve, as well as a high minimal annual volume to maintain competency. In this study, we analyzed data from 16 international centers comprising 3403 patients from the inception of their TAVR programs. The study identified an important learning curve, with higher mortality for the first 225 cases compared to those performed after > 300 case volume, and higher combined major complications up until a 300-case volume. In addition, the 30-day mortality was higher for centers performing
EFFECT OF LOW CONSISTENCY REFINING AND FRACTIONATION ON FOLDING BOXBOARDS AND DISCRETE ELEMENT MODELLING OF PLYBOND STRENGTH
Keywords: Discrete Element Method
Folding Boxboard
Fractionation
Low Consistency Refining
Mechanical Pulping
Plybond

The effect of using fractionation screens after primary high consistency (HC) refining and prior to low consistency (LC) refining on pulp properties being used as the middle-ply furnish of folding boxboards (FBBs) is investigated. Middle-ply furnish was a mixture of accept and reject pulps resulted from various screening designs, a range of specific refining energies (SRE), and two levels of specific edge load (SEL) and were compared with pulps with no screening stage. Fractionation and LC refining decreased refining energy consumption, and improved fibre uniformity resulting in optimum conditions for physical properties compared to the conventional refining processes. Plybond strength of multi-ply paperboards is modelled using Discrete Elements Method (DEM). Simulated three-ply boards were generated computationally and were subjected to z-directional tensile stress using ESyS-Particles software. It was found that plybond strength of simulated boards can be expressed by a scaling relationship in terms of paperboard density and bond strength.
Investigation of an Electrospun Nanofibrous, Degradable Polar Hydrophobic Ionic Polyurethane Patch for Cardiac Tissue Regeneration
Keywords: Biomaterial
Cardiac tissue engineering
Cardiomyocytes
Polyurethane
Scaffold
Surface chemistry

Cardiac tissue engineering (CTE) can be used to repair and replace the damaged myocardium due to coronary artery disease. An electrospun nanofibrous, degradable polar hydrophobic ionic polyurethane/polycarbonate polyurethane (D-PHI/PCNU) scaffold was generated and characterized for CTE applications. In addition, induced pluripotent stem cell derived cardiomyocytes (iPSC-CMs) were assessed for their compatibility on the D-PHI/PCNU scaffold. D-PHI/PCNU scaffolds had a high cross-linking efficiency, higher surface energy, and lower stiffness relative to PCNU scaffolds. In vivo, the D-PHI/PCNU scaffold degraded relatively slowly, but was well integrated with the surrounding tissue. Furthermore, the aligned D-PHI/PCNU scaffolds were able to support high iPSC-CM viability, adhesion, and expression of functional cardiac markers after a 7-day culture period. The iPSC-CMs had a more elongated and aligned phenotype on aligned D-PHI/PCNU scaffolds as compared to on random D-PHI/PCNU scaffolds and on TCPS. This work demonstrates the potential of using D-PHI/PCNU scaffolds as a platform for CTE.
Exploration of naturalistic driving data: Development of distracted driver behaviour models
Keywords: Distracted Driving
Driver Behaviour Models
Environmental Demands
Naturalistic Driving Data
NEST Dataset
Secondary Task Engagement

Distraction is detrimental to traffic safety. This thesis provides insights into distracted driving behaviours through two research objectives explored on naturalistic driving data: 1) distraction engagement behaviours and visual attention allocation as a function of varying environmental demands, and 2) engagement in multiple types of secondary tasks. For this purpose, Naturalistic Engagement in Secondary Tasks (NEST) dataset was utilized. Through inferential statistics, it was shown that higher visual difficulty in the driving environment is associated with a decreased likelihood of distraction engagement, and a decrease in non-forward glances with the likelihood of longer glances (> 2s) being reduced to a larger extent compared to shorter ones (> 1.6s). Drivers 35 and older have reduced rates of non-forward glances compared to younger drivers. Moreover, the results demonstrate that engagement in multiple secondary task types is prevalent, and is more likely to occur in safety-critical as opposed to non-safety critical situations (baselines).
Voxel-based Analysis of Cholinesterase Inhibitor Response in Lewy Body Disorders: A Prospective Observational Study
Keywords: Cholinesterase inhibitor
Lewy body disease
SPECT imaging

Lewy body disorders (LBD) have visual hallucinations, fluctuations in attention and alertness, and parkinsonism as common features. While cholinesterase inhibitors (ChEIs) are an effective treatment for LBD, our understanding of the effects of these drugs in the brain in relation to response is limited. The objective is to investigate functional neuroimaging correlates of response to ChEIs. Standardized neuropsychiatric and neuropsychological batteries and brain perfusion SPECT scans were completed at baseline and after six-months following initiation of ChEIs. This study investigated longitudinal relationships between changes in battery test scores and perfusion using statistical parametric mapping. Treatment with ChEIs resulted in significantly increased occipital perfusion. Significant improvements in working memory, visuospatial performance, and executive functions were observed. Visual hallucinations were significantly reduced, which correlated with increased occipital perfusion. This study identified occipital perfusion as an important correlate of response to ChEIs in LBD, which could be further developed as a response biomarker.
On the Generation of Unsteady Mean and Turbulent Flows in a Wind Tunnel using an Active Grid
Keywords: active grid
unsteady aerodynamics
unsteady turbulence

Unsteady flows are pervasive in nature and engineering applications such as UAVs. Simulating these flows in an experimental setting is key to avoiding detrimental changes in the performance of such applications. This study explores the capabilities of an active grid in producing unsteady flows in a recirculating wind tunnel. The grid is operated in different modes that allow control over the flow frequency, amplitude and turbulence intensity. Hot-wire measurements demonstrate the grid's capabilities in generating flows typical of those used in experiments of unsteady aerodynamics. Mean grid blockage, freestream speed and tunnel size were all found to be factors influencing the resulting flow. The response of turbulence to the oscillating flow was also investigated and results showed a modulation of the turbulence intensity and dissipation rate that is dependent on the frequency of the imposed oscillations. A change in the scaling behaviour of the dissipation rate was also noted.
The Investigation of Transient Wake Dynamics in Highly-Loaded High-Pressure Turbine Stages under Transonic Engine Conditions
Keywords: Blade Loading
High-Pressure Turbine
Phase-Conditioning
Transonic
Unsteady Fluid Mechanics
Wake Development

The convection of unsteady wakes through a downstream blade row and the interaction of these wakes with subsequent blade wakes were investigated in characteristic highly-loaded high-pressure turbine cascades under engine relevant conditions (Ma=0.69 and Re=3,8x10^5). Phase conditioned PIV measurements were obtained in the aft portion of the blade channel and downstream of the trailing edge. Two blade designs were investigated - one front-loaded, one aft-loaded. Wake convection kinematics are discussed, and the development of turbulence properties are linked to measured efficiency losses. The front-loaded design proved inferior to the aft-loaded, with ~30% higher peak turbulence kinetic energy and ~10% greater total pressure loss. The trailing edge wake modulated through constructive and destructive vorticity interactions and was linked to a higher harmonic of the convected wake cycle. This study contributes to a full characterisation of the unsteady flow field of a high-pressure turbine, leading to innovative methods of efficiency improvement.
Mechanisms of Pharmaceutical and Personal Care Product Removal in Algae-Based Wastewater Treatment
Keywords: Algae
Environment
Pharmaceutical
Wastewater
Water Treatment

Algae-based wastewater treatment is a form of passive wastewater treatment used to treat municipal and agricultural wastewaters. While pharmaceutical and personal care product (PPCP) treatment has been observed, the removal mechanisms in these systems are poorly understood. In this study, lab-scale algal bioreactors were used to simulate algae-based wastewater treatment. Concentrations of carbamazepine, ibuprofen, gemfibrozil, and triclosan were monitored in these reactors alongside controls designed to isolate and elucidate removal processes. Ibuprofen was primarily treated by biotransformation, which was dependent on interactions of algae with the bacteria and media. Triclosan was rapidly phototransformed, though there was evidence of biodegradation or sorption. There was no evidence of carbamazepine and gemfibrozil treatment in algae-based wastewater systems. Based on the results of these experiments, algae can facilitate PPCP removal in passive water treatment systems. Further research on PPCP removal in these systems should be focused on the interactions between bacteria, algae, and media.
In and Out: Exploring Inclusion and Alienation within the Sport Experiences of Hijabi Athletes in Ontario
Keywords: Identity
Islamophobia
Muslim Women
Social research
Social Support
Sport

Western sport environments may create challenges for young Muslim women who choose to participate while adhering to their Islamic values and principles. In this way, participation in sport may serve to exclude young Muslim women when cultural and religious needs are not met. The purpose of this study was to explore how young Muslim women who wear the hijab experience inclusion or alienation due to their involvement in sport in Ontario. Data collection with seven Hijabi athletes consisted of semi-structured interviews and audio-diaries recorded over a one-month period to examine identity negotiation, social interactions with non-Muslim teammates and coaches, and the influence of broader discourses on the sport experiences of young Muslim women. Results pertained to solidarity as well as Islamophobic interactions with teammates, surveillance due to hypervisibility of the hijab, and behaviour modification. This research highlights the heterogeneity of Muslim women in Ontario and how they navigate sport experiences.