VictorJuiz/thesis huggingface dataset:
Predicting Designer Performance in Generating Reuse Concepts for Retired Wind-Turbine Blades by Measuring Individual Differences
Keywords: Component reuse
Concept generation
Functional fixedness
Regulatory mode theory
Sustainability
Wind-turbine blades

This work examines identifying reuses for wind-turbine blades that are retired when they reach the end of their technical life. Wind-turbine blades are made from fiber-composite materials, for which effective material-based recycling technologies are extremely limited. An approach to avoid or postpone recycling is to repurpose wind-turbine blades in other applications, as they should not be reused as wind-turbine blades for safety reasons. However, identifying promising reuses for wind-turbine blades is challenging due to their specific shape properties. In addition to issues of functional fixedness, wind-turbine blades are physically much larger than everyday objects with which people typically reason. Following a series of studies where students were asked to identify wind-turbine-blade reuses, a method involving perspective-taking was developed and applied. To better understand and motivate human designers, this work also incorporates psychological concepts, including Need for Closure, Regulatory Focus Theory, and Regulatory Mode Theory.
Prefrontal Cortex Activity during Dual Task Performance in Patients with Chronic Obstructive Pulmonary Disease
Keywords: Aging
Chronic Obstructive Pulmonary Disease
Cognition
Gait
Near-Infrared Spectroscopy
Prefrontal Cortex

The purpose of this study was to compare changes in dorsolateral prefrontal cortex (DLPFC) oxygenated hemoglobin (ΔO2Hb), accuracy of backwards spelling, and decrements in gait velocity during single and dual tasks in patients with COPD (n=8), and healthy younger (n=20) and older adults (n=20). Participants performed: (1) backwards spelling cognitive task (CT); (2) preferred paced walk (PPW); and (3) fast paced walk (FPW). The dual tasks then paired CT with PPW and FPW. In older adults, ΔO2Hb was significantly higher in left DLPFC compared to patients with COPD and bilaterally compared to younger adults during FPW+CT versus FPW. Furthermore, older and younger adults exhibited higher decrements of velocity during FPW+CT compared to PPW+CT. CT accuracy tended to be lower in older adults. Decrements in performance during dual tasking highlight the impact of increased cognitive load and need of cognitive-motor interventions to improve cognition and physical function.
A Population-based Study of Individuals with Schizophrenia and Correctional Involvement
Keywords: Health Service Utilization
Ontario
Provincial Correctional Involvement
Recidivism
Schizophrenia

The purpose of this study was to describe characteristics of individuals with and without schizophrenia within a Canadian correctional population. This cohort study included 46,928 individuals who were released from Ontario’s provincial correctional facilities from January 1 to December 31, 2010. Survival analysis was used to examine how schizophrenia, incarceration, comorbidity and healthcare utilization were associated with recidivism in this cohort; each of these variables showed a decrease in the risk rate of recidivism. The study results show that the schizophrenia prevalence within this cohort was 7%. Approximately 67.5% of schizophrenic individuals were reincarcerated within five years following the index incarceration, compared to 58.8% of individuals without schizophrenia. Individuals with schizophrenia were 40% (aHR: 1.39) more likely to have a reincarceration event following release than the comparative group. Descriptively, individuals with schizophrenia experienced a higher number of correctional events and higher rates of healthcare utilization throughout the observational period.
Predicting Formalin-fixed Paraffin-embedded (FFPE) Sequencing Artefacts from Breast Cancer Exome Sequencing Data using Machine Learning
Keywords: Computational biology
DNA damage
FFPE
Machine learning
Sequencing artefacts

Cancer is a lethal disease caused by the accumulation of genomic alterations. In order to investigate these diseases, cancer genome studies have largely relied on fresh frozen tissues. However, fresh frozen material is often unavailable for large-scale studies. In contrast, formalin-fixed paraffin-embedded (FFPE) tissues are abundantly available but difficult to use due to severe DNA degradation resulting in artefactual mutations. Accurate removal of these sequencing artefacts can help enable the widespread use of FFPE material for molecular analysis of cancers and other diseases. In this project, I used commercial FFPE DNA repair and library preparation kits and trained a random forest classifier to reduce the number of sequencing artefacts in FFPE breast cancer exome data. These experiments show that the classifier is able to retain the majority of true somatic variants while filtering many FFPE-induced sequencing artefacts and is suitable for application to low-quality FFPE breast cancer exomes.
Exploiting the Cellular Redox Control System for Activatable Photodynamic Therapy
Keywords: Cancer
Glutathione
Photodynamic Therapy
Photosensitizer
Protein Disulfide Isomerase
Redox

Photodynamic therapy is a clinically-approved cancer treatment that uses a small-molecule photosensitizer, light and molecular oxygen to produce cytotoxic reactive oxygen species to promote cell death. Photodynamic therapy uses visible light for destruction of tumors, while their fluorescent properties make them useful for fluorescence-guided surgery. However, the lack of cancer cell selectivity has limited the use of current photosensitizers for cancer treatment. To overcome this, we designed activatable photosensitizers whereby in addition to light, activation depends on elements of the over-active redox system found in cancer cells. Chapter 1 provides a comprehensive overview on photodynamic therapy, photosensitizers and their applications. In chapter 2, we highlight the development and applications of an activatable photosensitizer sensitive to multiple elements of the redox system. Chapter 3 provides an overview of an activatable photosensitizer specific for protein disulfide isomerase. Finally, in chapter 4, we highlight the development and characterization of other enzyme activatable photosensitizers.
Evaluating Glutathione Peroxidase Activity as a Marker of Cognitive Impairment in Coronary Artery Disease Patients
Keywords: biomarker
Cognitive impairment
Coronary Artery Disease
glutathione peroxidase

Coronary artery disease (CAD) patients are at risk for vascular cognitive impairment (VCI), yet mechanisms remain elusive. We hypothesized that glutathione peroxidase activity (GPx), which protects from oxidative damage, would be higher in CAD patients with cognitive impairment (n=36) compared to those without (n=84), and baseline GPx and change in GPx over 6 months would be associated with changes in verbal memory. CAD patients were recruited from the Toronto Rehabilitation Institute Cardiac Rehab (TRI-CR) program. Cognitive performance and GPx activity were measured at baseline and 6-month timepoints. GPx was significantly elevated in those with cognitive impairment (F1,119=3.996, p=0.048). While a 1 nmol/min/mL increase in GPx activity was associated with a decrease in verbal memory z-scores by 0.02 standard deviations (SD) over 6 months (b=-0.02, df=184.65, p=0.004), baseline GPx did not predict change in verbal memory. This research suggests that alterations in GPx activity may be associated with cognition in CAD patients.
Effects of Self-regulated Strategy Development on the Writing Performance and Sense of Self-efficacy of Postsecondary English Language Learners
Keywords: ELL
postsecondary
second language writing
self-efficacy
Self-Regulated Strategy Development
strategy instruction

English language learners (ELLs) comprise a growing contingent in North American postsecondary institutions. However, success in postsecondary requires competence in written expression, a taxing activity for most ELLs. To foster writing development, this study adapted the strategy instruction model of Self-Regulated Strategy Development (SRSD; Graham Harris, 1996) to teach strategies for research writing and vocabulary expansion. Six postsecondary ELLs received 36 hours of instruction over six weeks. Collecting data through a mixed methods design, the study measured performance gains as high as 10%, which, though moderate, contribute to growing evidence for the effectiveness of SRSD among postsecondary ELLs. Participants also reported positive transformations in their sense of self-efficacy alongside elevated confidence and lowered anxiety and stress. The study highlights the importance of guiding postsecondary ELLs through the framework of writing strategy instruction and suggests that SRSD may benefit writers by both teaching new strategies and validating existing writing practices.
Endothelial Heterogeneity: A Role for Epigenetic Pathways in Constitutive Gene Expression
Keywords: DNA methylation
Epigenetics
Gene regulation
Heterogeneity
P-selectin
Vascular biology

Endothelial cells (ECs) have distinct gene expression and morphology depending on their location in the vasculature. A prevailing assumption is that these differences are largely caused by environmental factors, which differentially modulate gene expression in an otherwise homogeneous cell population. Here, we investigated the mechanistic basis for heterogeneity in EC gene expression and its functional importance, using P-selectin as a model gene. We found that heterogeneity exists basally in P-selectin protein expression across several human EC types. RNA FISH also showed heterogeneity in SELP transcription in isogenic populations of human umbilical vein endothelial cells (HUVEC). Differential proximal promoter DNA methylation, in part, accounted for this protein and RNA heterogeneity. In vitro methylation of the SELP promoter repressed transcription in episomal promoter reporter transfections. Importantly, promoter methylation was shown to be mitotically heritable. Using informative heterozygous SNPs in the SELP gene, we also report that P-selectin is monoallelically expressed in HUVEC.
Acquired Low Immunoglobulin Levels and Risk of Clinically Relevant Infection in Adult Patients with Systemic Lupus Erythematosus Cohort Study
Keywords: Cohort
Immunoglobulins
Infection
Lupus erythematosus
Observational

Infection is a leading cause of mortality in systemic lupus erythematosus (SLE). Low immunoglobulin levels might be a potential risk for infection. We aim to examine the effect of acquired hypogammaglobulinemia on risk of infection in adults with SLE. Methods: We used Toronto Lupus Cohort to compare adult SLE patients who had acquired any low immunoglobulin levels to those who did not with respect to infection using time to event analysis. Several propensity score methods were used to improve group balance. Results: Patients with hypogammaglobulinemia had longer disease duration, more proteinuria and history of lupus nephritis. Low IgA levels increased the risk of infection. Recovery of immunoglobulins occurred in 64 percent of acquired hypogammaglobulinemia over four years. Conclusion: The majority of acquired hypogammaglobulinemia in adults with SLE is transient. Only low acquired IgA increases the risk of infection among adult patients with SLE. Mechanism of this association requires further investigation.
Childhood Disability and School Travel
Keywords: access
accessible busing
disability
education
excess travel
school travel

There has been little research on children living with disabilities that use school boards’ accessible bus services, and no attention has been paid to their differences in excess travel compared to their non-disabled peers. This thesis explores the literature on childhood disability and school travel in order to identify current knowledge gaps and provide potential future research recommendations. In addition to, examining whether or not children with disabilities experience greater excess travel than their non-disabled peers when using accessible school buses and why? The results indicate that children with disabilities are experiencing significant inequalities in their school trips due to the much higher amounts of wasteful travel they encounter than non-disabled children. The findings also suggest there are numerous issues of ableism and disablism within educational settings that may have substantial influence on education access and school mobility for disabled children with potential long-term impacts.
Intervention for Arch Obstruction After Norwood: Prevalence, Associated Factors, and Practice Variability
Keywords: arch intervention
complications
congenital cardiac surgery
Norwood procedure
parametric hazard analysis
survival

Aortic arch obstruction after Norwood is common and causes mortality. We analyzed arch reinterventions after Norwood to determine associated factors and association with mortality. From 2005-2017, 593 neonates underwent a Norwood procedure. Multivariable parametric models, including a modulated renewal analysis, were performed. There were 218 arch reinterventions in 146 patients (25%) at median age 4.3 months. Factors associated with reduced risk for arch reintervention included: interdigitation of the distal aortic anastomosis and prior surgical arch reintervention. Factors associated with increased risk for arch reintervention included: development of tricuspid valve regurgitation and right ventricular dysfunction and transcatheter reintervention. Non-significant variables included: shunt type, coarctectomy, and pre-Norwood aortic measurements. Reintervention was not associated with increased mortality. There was wide institutional variation in arch reintervention practices. Serial surveillance for arch obstruction, including changes in right ventricular function and tricuspid valve regurgitation, is recommended after Norwood to enable prompt treatment of post-Norwood arch obstruction.
Anchorage of Single Leg Stirrups in Reinforced Concrete Slabs and Walls
Keywords: anchorage
concrete
hook
rebar
single leg
stirrup

According to CSA A23.3-14, stirrups shall be anchored by standard hooks or by heads of headed bars. In almost all applications, standard stirrup hooks require a bend of at least 135°. However, single leg stirrups with 135° hooks on both ends can be difficult to place in rebar cages. The purpose of this research was to compare the anchorage of single leg stirrups with 90° hooks, 135° hooks, 180° hooks, and T-headed bars. Four beams were made to test varying combinations of each kind of stirrup anchor. It was observed that stirrups with one 90° hook and one 135° hook were significantly weaker than stirrups with two 135° hooks. Stirrups with one 180° hook and one T-head were observed to be slightly weaker, but within 10% of the strength of stirrups with two 135° hooks. The results also indicated potential issues with the current CSA provisions for 15M stirrup anchorage.
Full-scale Monitoring of a Tall, Slender Building with Coupling Viscoelastic Dampers
Keywords: Damping
Monitoring
Structural Dynamics
Structural Engineering
Tall Buildings
Viscoelastic Coupling Damper

Tall, slender buildings are sensitive to dynamic vibrations caused by wind, and the design of the building may be governed by occupant motion perception. A method to control dynamic vibrations is to increase the damping of the structure, which may be accomplished by the addition of a supplemental damping system. A novel system, the Viscoelastic Coupling Damper (VCD), was implemented for the first time in a tall, slender building which was under construction during the completion of this thesis. This building was the subject of a year-long plus monitoring program where output-only system identification algorithms were applied to track the development of the dynamic properties through the construction of the building. Additionally, several large amplitude wind events occurred during the program allowing for the tracking of amplitude-dependent phenomenon. The role of the VCD system was evaluated, and numerical finite-element models were constructed with reference to the experimental results
Development of an In Vitro Outer Annulus Fibrosus-cartilage Endplate Model and its Response to Dynamic Mechanical Loading
Keywords: Annulus Fibrosus
Biomaterials
Cartilage Endplate
Intervertebral disc
Tissue engineering

Tissue-engineering research to date has neglected to address the annulus fibrosus (AF)-cartilage endplate (CEP) interface of the intervertebral disc. It was hypothesized that in vitro-formed outer AF and cartilage tissues will integrate in co-culture to form an interface containing ECM that resembles the native interface, and that can be mechanically and compositionally enhanced through dynamic loading. 2-week old in vitro OAF tissues integrated with 3-day old in vitro cartilage by 1 week of co-culture, and resembled the distributions of collagen type I, collagen type II, and aggrecan seen in the native interface. The apparent tensile strength of the in vitro interface increased between 2 and 4 weeks of co-culture. Dynamic mechanical loading did not enhance the mechanical strength, appearance, or composition of the interfacial matrix. This study demonstrated the ability to engineer a biological AF-CEP interface model, and will assist in defining how future tissue-engineered disc replacements should be developed.
Combined Multimodal Cerebral Monitoring and Serial Hemodynamic Assessments at the Bedside in the First 72 Hours after Birth in Extremely Low Gestational Age Preterm Infants
Keywords: amplitude integrated EEG
cerebral saturation
echocardiography
Intraventricular Hemorrhage
neuro-monitoring
preterm

Previous research on intraventricular hemorrhage in preterm infants has shown that characteristic patterns of cerebral monitoring or echocardiography parameters measured during the transitional period after birth are associated with, and may precede its occurrence. Clinical application of combined cerebral and hemodynamic monitoring in preterm infants has not been previously studied. In a cohort of 50 preterm infants born at gestational ages between 23+0 and 27+6 weeks, we prospectively demonstrated the feasibility and safety of using a combination of cerebral near infrared spectroscopy, amplitude integrated electroencephalography, sequential head ultrasound and echocardiography, in the first 72 hours after birth. Application of multimodal monitoring was feasible in 49 (98%) of infants. We characterized the patterns of measurements in infants with and without intraventricular hemorrhage. Our work lays foundation for future research on brain and heart monitoring for early identification of preterm infants at risk of developing brain injury.
Examining the Use of Wireless Physical Activity Monitors Among Adults Living with HIV
Keywords: HIV
Measurement
Physical Activity
Wireless Physical Activity Monitor

Background: Wireless physical activity monitors (WPAMs) are used to measure physical activity among healthy and chronic illness populations, however their use and measurement properties in the context of HIV are unclear. Methods: I conducted a Scoping Review using the Arksey and O’Malley framework and a cross-sectional measurement study to assess criterion and construct validity of the Fitbit Zip® to measure physical activity among adults living with HIV. Results: Twenty-five articles were included in the scoping review. WPAMs were used primarily as a measure of physical activity, and to a lesser extent a motivational tool to enhance physical activity. The cross-sectional measurement study provided evidence of criterion validity of the Fitbit Zip® to measure steps taken but not distance walked (m) and did not establish construct validity for measuring physical activity. Conclusion: Results provide directions for future research including, physical activity promotion using WPAMs and assessing measurement properties of other WPAMs.
Building Clinically Relevant Thermal Simulation Tools for High Intensity Focused Ultrasound Therapy in Soft Tissue
Keywords: Acoustics
Bioheat
Computational Modelling
Focused Ultrasound
Parallel Programming
Wave Propogation

Magnetic Resonance guided High Intensity Focused Ultrasound (MRgFUS) therapy is a non-invasive thermotherapy, with a range of potential applications, including paediatric soft tissue tumours. The aim of this project is to create a clinically-relevant, modular MRgFUS simulation tool. The tool was developed using Python, open-source python libraries, and CUDA, a library for parallel computing. Validation of the simulator was achieved through the comparison of simulated and experimental sonications of ex vivo agar-sealed porcine kidney (n=4) and liver (n=4) tissue samples. The tool was analyzed using four metrics: peak temperature difference, cool down rate, ablation ratio, and spatial accuracy. This generalized software simulation tool will help to bring MRgFUS therapy one-step closer to being the clinical standard across a wide range of complex conditions.
Early Cardiac Remodeling in Women with Breast Cancer, Receiving Sequential Therapy with Anthracycline and Trastuzumab – Cardiac MRI Study
Keywords: Breast Cancer
Cardiac MRI
Cardiotoxicity
Healthy Volunteers
Postprocessing
Temporal Variability

Background: Cardiotoxicity is an adverse prognostic marker in women with early-stage breast cancer. Understanding cardiac changes using cardiac-MRI will provide the opportunity to establish predictive models for early detection of cardiotoxicity. Methods: Eighty-three patients had cardiac MRI pre-anthracycline, within three weeks post-anthracycline, and at five months (~three months into trastuzumab therapy) on a 1.5T scanner; along with thirty volunteers scanned at matched time points. Results: Temporal and inter-observer test-retest variability, repeatability, and reproducibly of left and right ventricular volumetric parameters in healthy volunteers were statistically small. Ten patients (12.1%) developed LV-cardiotoxicity, 1 (10%) at 2 months and 9 (90%) at 5 months. LV-cardiotoxicity was associated with a significant increase in LVESV in 91% of the patients. Conclusions: Ventricular remodeling occurs during cancer therapy. The primary mechanism of cardiotoxicity is likely a reduction in contractility. Change in LVESV at 2 months is an early predictor of cardiotoxicity by 5 months.
Arabidopsis thaliana Meiosis: HOP2 Interactions with Proteins and Chromatin
Keywords: Chromatin interaction
Homologous recombination
HOP2
Meiosis
Protein interaction

Homologous Pairing 2 protein (HOP2) is believed to play a crucial role in meiosis by promoting pairing of homologous chromosomes in anticipation of recombination. The loss of HOP2 causes a multitude of meiotic aberrations leading to sterility in yeast, mice, and plants. My research focuses on the Arabidopsis thaliana HOP2 homolog and its interactions with proteins and chromatin. In this study, using co-immunoprecipitation and chromatin immunoprecipitation assays, I set out to confirm existing and identify novel protein-protein interactions involving HOP2. Moreover, I attempt to elucidate the manner in which HOP2 interacts with chromatin. I demonstrate the in vivo interaction of HOP2 with Meiotic Nuclear Division 1 protein (MND1) and the preferential interaction of HOP2 with euchromatin which follows crossover occurrence patterns in Arabidopsis thaliana. My research corroborates previous findings regarding HOP2-protein interactions and provides a basis for HOP2 studies involving chromatin interactions.