VictorJuiz/thesis huggingface dataset:
Superhydrophobic Ceramic Coatings by Solution Precursor Plasma Spray

Superhydrophobic surfaces exhibit superior water repellent properties, and they have remarkable potential to improve current energy infrastructure. Substantial research has been performed on the production of superhydrophobic coatings. However, superhydrophobic coatings have not yet been adopted in many industries where potential applications exist due to the limited durability of the coating materials and the complex and costly fabrication processes. Here presented a novel coating technique to manufacture ceramic superhydrophobic coatings rapidly and economically. A rare earth oxide (REO) was selected as the coating material due to its hydrophobic nature and strong mechanical properties, and deposited on stainless steel substrates by solution precursor plasma spray (SPPS). The as-sprayed coating demonstrated a hierarchically structured coating topography, which closely resembles superhydrophobic surfaces in nature. Compared to smooth REO surfaces, the SPPS superhydrophobic coating improved the water contact angle by as much as 65° after vacuum treatment at 1 Pa for 48 hours.

Keywords: Ceramics
Solution precursor plasma spary
Superhydrophobic coating
Advisor: Mostaghimi, Javad
Coyle, Thomas W
Velutin Modulates the Expression of HIF-1a via the NF-kB Pathway during Osteoclastogenesis

HIF-1a has been implicated in periodontal tissue inflammation, while polyphenols are known anti-inflammatory natural compounds that can modulate the NF-kB pathway. Our aim was to investigate HIF-1a expression through NF-kB modulation by the polyphenol velutin during osteoclastogenesis. Methods: RAW 264.7 cells were evaluated with/without RANKL (30ng/mL)/Pg LPS (1µg/mL) and treated with velutin (0.5-2µM) to evaluate nuclei morphology, viability, osteoclast differentiation, and HIF-1a expression. Results: DAPI staining showed no alteration in the morphology of cells nuclei (p>0.05). Velutin did not induce cell apoptosis based on caspase 3/7 analysis (p>0.05) and Alamar blue showed no toxicity to the cells (p>0.05). TRAP assays demonstrated reduction in osteoclast formation by velutin (p

Keywords: Hif-1a
NF-kB
Osteoclast
osteoclastogenesis
Porphyromonas gingivalis
Velutin
Advisor: Prakki, Anuradha
Empathy and the Subjective-behavioural Effects of D1 and D2 Receptor Blockade in Pathological Gamblers

This study assessed the relationship between Empathy and reinforcing effects of gambling and a psychostimulant drug, in 30 otherwise healthy pathological gamblers (PGs). To explore the roles of dopamine D1 and D2 receptors in these relationships, subjects received either: D2 antagonist, haloperidol (3-mg) or D1-D2 antagonist, fluphenazine (3-mg), in a placebo-controlled, double-blind, counterbalanced design. On separate sessions, subjects played a 15-minute slot machine game and received d-amphetamine (AMPH; 20-mg, oral). Under placebo, Empathy correlated positively with Desire to Gamble (DTG) at all time-points in both groups. Haloperidol negated, whereas fluphenazine enhanced, the correlation between Empathy and pleasurable effects of the slot machine. Haloperidol enhanced, whereas fluphenazine attenuated, the correlation between Empathy and DTG under AMPH. Results suggest post- synaptic D2 receptors may mediate Empathy-related differences in Liking of gambling; D1 receptors may mediate Empathy-related differences in Wanting to gamble under AMPH in PGs. Low statistical power and restricted generalizability were limitations.

Keywords: Dopamine
Empathy
Liking
Pathological Gambling
Wanting
Advisor: Zack, Martin
Youth Athletes' Interpretations of Punishment in Hockey

The purpose of this study was to explore competitive youth hockey athletes’ interpretations of punishment. Semi-structured interviews and concept maps were conducted with 12 (7 male and 5 female) hockey athletes between the ages of 11-13 years. All data were analyzed according to inductive thematic analysis (Braun Clarke, 2006). Results revealed that punishments reportedly occurred in competitive hockey frequently in the forms of benching, yelling, and forced physical conditioning; in addition, these methods appear to be normalized within the sport context, and reportedly have detrimental effects on athletes. The findings are interpreted according to various theoretical frameworks, which include: the sport ethic (Hughes Coakley, 1991), cognitive-motivational-relational theory (Lazarus, 1999), psychosocial development (Erikson, 1968), and youth sport attrition (Weiss Williams, 2004). Implications and recommendations for future research in this field of study are discussed.

Keywords: Coach-athlete relationship
Hockey
Punishment
Youth Athletes
Advisor: Kerr, Gretchen
Testing the Sensorimotor Fluency Account of Mimicry

Mimicry is a pervasive and ubiquitous human behaviour with generally positive consequences, resulting in increased liking, closeness, and smoothness between interaction partners. Whereas previous research has stressed the affiliative aspect of these consequences, recent research suggests that these consequences may also arise because of the sensorimotor fluency with which mimicry is achieved. I tested three key hypotheses of this model in two experiments and found no support for a sensorimotor fluency account of mimicry. Implications of this research are discussed.

Keywords: Human mirror system
Mimicry
Processing fluency
Advisor: Rule, Nicholas O
The Face of a Nation: The Effect of Nationality on Face Memory and Perception

Nationality is a pervasive group membership, and previous research has variously demonstrated its potency. However, little work has investigated nationality’s relationship with person perception, an area ripe for research in today’s globalized world. Thus, the aim of this thesis was to understand how nationality affects one’s perception and memory of others. I tested how randomly pairing faces with Canadian and foreign flags affected Canadians’ memory and trait evaluations for these faces and whether nationalism predicted ingroup favouritism. I also compared memory differences for ostensible national ingroup and outgroup members to that for university ingroup and outgroup members to determine the relative importance and strength of nationality over other social identities. Across three studies, I found that Canadian participants recognized faces randomly paired with the Canadian flag better than those paired with a foreign flag, suggesting that nationality labels can affect memory for others, which has important implications for cross-national interactions.

Keywords: face perception
ingroup favouritism
memory
nationality
person perception
Advisor: Rule, Nicholas O
Evaluation of Concretes Exposed to Sulfate Solutions for 38 Years

In 1975, a separately ground blast furnace slag was developed in Hamilton, Ontario, and a research program was begun in 1977 to study the effects of this slag on sulfate resistance of concrete. Concrete cylinders were cast from 8 batches using Portland cement types GU, MS, HS, and mixtures of GU plus slag at w/cm of 0.45 or 0.50. In this study, cylinders were removed from the sulfate solutions and thin sections were prepared for SEM/EDS analysis. Microstructural details were investigated, and different phases were determined. Qualitative maps were also prepared using Micro-XRF. Ettringite, thaumasite, and gypsum as well as layers of brucite and/or calcium carbonate were found to have formed in the samples. A 65% slag substitution was the most effective in improving the performance of concrete exposed to sodium sulfate. However, the damage caused by magnesium sulfate was found to be more severe than by the sodium sulfate.

Advisor: Hooton, R D
Increasing Void Fraction of the Polypropylene Foams Blown with Chemical Blowing Agents in High Temperature Extrusion

The global demand for the polymeric foams especially Polypropylene (PP) foams is increasing rapidly. Some industrial processing of the PP foam need high processing temperature. But, there are only a few research has been done on high temperature processing as the quality of foam deteriorates in that condition. Moreover, Physical Blowing Agents (PBA) need additional accessories to process the foam. But usually industries are reluctant to change their existing system to get foamed output initially. This thesis develops an approach to manufacture PP foams with Chemical Blowing Agents (CBA) in high temperature extrusion. In the first step, a series of fundamental studies have been carried out by investigating the effect of different chemical blowing agent and content, pressure drop rate and residence time on the foaming behavior of polypropylene. And then, optimized parameters are applied and the combination effect of CBA-PBA and the effect of nucleating agents has been examined.

Keywords: Chemical Blowing Agents
Extrusion
High Temperature
Polymeric Foams
Polypropylene
Void Fraction
Advisor: Park, Chul B.
Linear Stability Analysis, Dynamic Response, and Design of Shimmy Dampers for Main Landing Gears

This thesis presents the linear stability analysis and dynamic response of shimmy dampers for main landing gears. The stability analysis is performed using a single tire landing gear model along with the dynamics of the shimmy dampers and the stretched string tire model. The dynamic response of each damper is obtained through a multibody model developed in MSC Adams and validated using existing literature. Two shimmy dampers are the focus of this study, one developed by Boeing and the other by UTC Aerospace systems. Finally, a new and improved shimmy damper is proposed showing the stability regions and its dynamic response. The proposed damper is lighter, easier to manufacture, to install, and to maintain, and has an overall better dynamic performance.

Keywords: Dynamic response
Main landing gears
Shimmy dampers
Stability analysis
Vibrations
Advisor: Behdinan, Kamran
Zu, Jean W.
Bioengineering Human Scaffold-free Cartilage Constructs Using Paediatric Auricular Tissue

Currently, patients with external ear deformities rely on hyaline cartilage grafts or silicone prosthesis to provide them with adequate external ear reconstruction. Scaffold-free auricular tissue engineering provides a means of creating patient specific cartilage constructs solely using their own cells, ensuring biocompatibility, long term stability, and reduced morbidity. Here, we have developed a simple method for generating scaffold-free auricular constructs using paediatric auricular cartilage remnants. High cell density micromass cultures treated with chondrogenic medium for prolonged periods result in mechanically stable cartilage constructs resembling native paediatric auricular cartilage mechanically, histologically, immunohistochemically, and biochemically.

Keywords: Auricular
Cartilage
Microtia
Scaffold-free
Tissue Engineering
Advisor: Yeger, Herman
Farhat, Walid
Audio Cueing and Negative Adaptation in Older and Younger Drivers Using Lane Departure Warning Systems

A Lane Departure Warning Systems (LDWS) is an automation system that can be integrated in vehicles. Empirical research has demonstrated conflicting results about the effectiveness of LDWS, which may be attributable to inconsistent warning cues, adaptation effects, and differences among user populations. In this thesis, I investigated whether meaningful or non-meaningful auditory cues are more effective in improving lane keeping in older and younger drivers, and if adaptation occurs with the use of either/both cue types when the LDWS was intermittently turned off. Results showed LDWS were initially helpful in reducing lane deviations, regardless of cue type, with non-meaningful cues showing slightly greater effectiveness, particularly in older adults. However, following exposure to LDWS, drivers exhibited short-term negative adaption to the system, displaying significantly more and larger lane deviations when the system was on compared to when it was off. Significant adaptation differences between younger and older adults were not observed.

Keywords: adaptation
audio cueing
automation
older drivers
Advisor: Furlan, Andrea
Campos, Jennifer
Steelmaking Process Control using Remote Ultraviolet Atomic Emission Spectroscopy

Steelmaking in North America is a multi-billion dollar industry that has faced tremendous economic and environmental pressure over the past few decades. Fierce competition has driven steel manufacturers to improve process efficiency through the development of real-time sensors to reduce operating costs. In particular, much attention has been focused on end point detection through furnace off gas analysis. Typically, off-gas analysis is done with extractive sampling and gas analyzers such as Non-dispersive Infrared Sensors (NDIR). Passive emission spectroscopy offers a more attractive approach to end point detection as the equipment can be setup remotely. Using high resolution UV spectroscopy and applying sophisticated emission line detection software, a correlation was observed between metal emissions and the process end point during field trials. This correlation indicates a relationship between the metal emissions and the status of a steelmaking melt which can be used to improve overall process efficiency.

Keywords: Atomic Emission Spectroscopy
Combustion
Process control
Spectroscopy
Steelmaking
Advisor: Thomson, Murray
Access to Deep Sedation and General Anasesthesia Services for Dental Patients: A Survey of Ontario Dentists

Background: Many patients need deep sedation or general anaesthesia (DS/GA) to undergo dental treatment as a result of fear, anxiety, disability, invasive dentistry, medical illness, or age. Objective: To assess barriers in accessing DS/GA as identified by dentists. Methods: An electronic survey was distributed to Ontario dentists (n=5507). Descriptive and regression analyses were performed. Results: With a response rate of 18.3%, one quarter (24.8%) of those surveyed report inadequate access to DS/GA. Those outside the Greater Toronto Area and in rural communities had higher odds of reporting this outcome. General dentists, part-time dentists, urban dentists, and dentists >64 years-old had higher odds of not utilizing DS/GA. Common reasons for not utilizing GA were lack of perceived need and additional costs. Dentists that utilize DS/GA indicate that additional patient costs represent the greatest barrier to care. Conclusion: Access to DS/GA in Ontario is not uniform and major barriers to care exist.

Keywords: access
anaesthesia
anesthesia
dental
ontario
sedation
Advisor: Azarpazhooh, Amir
KIR3DL1 Interaction with HLA-B27 is Altered by ERAP1 and Enhanced by MHC Class I Cross-linking

Ankylosing Spondylitis (AS) is an inflammatory arthritis linked to the antigen presenting molecule HLA-B27. The risk of AS is increased in patients possessing endoplasmic reticulum aminopeptidase-1 (ERAP1) polymorphisms, rs30187 and rs27044, encoding amino acid changes K528 and Q730, respectively. Dysfunction of ERAP1 is hypothesized to cause changes in expression of HLA-B27 peptide-HLA trimer (pHLA) and free heavy chain (FHC) ligands, on antigen presenting cells (APCs), which interact with natural killer (NK) cell receptor, KIR3DL1. Dysregulation of this pathway may be pathogenic in AS. APC cell lines expressing HLA-B27 were found to inhibit cytokine production of KIR3DL1+ NK cells due to decreased APC-NK cell adhesion and possibly activating receptor down-regulation. Blocking pHLA and FHC reveals both conformers inhibit cytokine production through KIR3DL1. KIR3DL1 affinity and HLA-B27 surface expression studies suggest ERAP1 R528 and E730 expression protects from AS by generating sub-optimal pHLA, causing reduced KIR3DL1 affinity and weaker cytokine inhibition.

Keywords: Ankylosing Spondylitis
Arthritis
ERAP1
HLA-B27
KIR3DL1
Natural Killer cells
Advisor: Inman, Robert D
Haroon, Nigil
Adolescent Disconnection from Brain Health and Impact on Brain Health Behaviour Decision-making

This qualitative content analysis study was preformed to understand the views about brain health held by high school students in grades 9 and 10, and how this impacts their adoption of brain healthy behaviours. Three semi-structured focus groups interviews were held with 23 high school adolescents in the Greater Toronto Area. Three themes regarding participants’ views on brain health emerged from the data analysis: (1) Ambiguous Definition, (2) Lack of Understanding and (3) a Struggle for Relevance. These themes contributed to adolescents feeling disconnected from the topic of brain health and its impact on their present and future lives. This emerged as a barrier to the adoption of healthy brain health behaviours. There is a need to address the divide between the youth of our generation and the topic of brain health through the creation and implementation of more meaningful learning experiences about the brain.

Keywords: adolescent
behaviour
brain
health
qualitative
Advisor: Chow, Tiffany
The Effects of Varenicline on Working Memory and Long-term Potentiation in Non-smokers with Schizophrenia

Background: Deficits in the nicotinic acetylcholine receptor (nAChR) system are proposed to underlie vulnerability to nicotine dependence and cognitive impairment in schizophrenia. Varenicline is a smoking cessation medication that enhances cognition in schizophrenia while treating nicotine dependence, possibly through the modulation of neuroplasticity. Methods: This study assessed the effects of varenicline (1 mg/day) versus placebo on neuroplasticity and working memory in 11 schizophrenia non-smokers and 11 non-smoker healthy subjects, to eliminate the confounding effects of tobacco smoking. Results: Patients with schizophrenia performed worse on the 3-back task compared to healthy subjects. Varenicline enhanced working memory in low-performers only, regardless of diagnosis. Deficits in neuroplasticity were found in patients with schizophrenia compared to healthy subjects, which were enhanced with varenicline compared to placebo. Conclusions: Varenicline may be a potential therapeutic option for the remediation of cognitive and neuroplasticity deficits in patients with schizophrenia regardless of smoking status.

Keywords: Long Term Potentiation
N-back Working Memory
Neurophysiology
Paired Associative Stimulation
Schizophrenia
Varenicline
Advisor: George, Tony P
Extra- and Intramuscular Innervation of Masseter: Implications for Facial Reanimation

Irreversible facial paralysis results in significant functional impairment. Despite its clinical importance, there are few innervation studies of the masseteric nerve (MN). The purpose was to investigate the extra- and intramuscular innervation of masseter in 3D. The MN throughout its entire course was dissected, digitized and modeled in 8 formalin-embalmed cadaveric specimens (mean age 84.9±12.2years). The nerve was digitized at 1-2mm intervals using a Microscribe™ Digitizer and modeled in 3D in Autodesk® Maya®. Two or three extramuscular nerves were found to enter the deep head (DH) of masseter: one main MN (n=8) and one (n=4) or two (n=4) smaller primary nerve(s). The main MN supplied both the DH and SH, whereas the smaller primary nerve(s) only supplied the DH. Surgical landmarks for MN localization were quantified. Comprehensive mapping of the innervation of masseter throughout its volume revealed neural partitioning that could provide a basis for surgical planning and simulation.

Advisor: Agur, Anne
Insulin Transcytosis across Adipose Microvascular Endothelial Cells: Mechanism and Physiological Implications

Transport of insulin across the microvasculature is necessary to reach its target organs (e.g. adipose and muscle) and is rate-limiting in insulin action. We report an approach to study insulin transcytosis across primary human adipose microvascular endothelial cells (HAMEC), involving insulin uptake followed by vesicle-mediated exocytosis visualized by total internal reflection fluorescence microscopy. In this setting, fluorophore-conjugated insulin exocytosis depended on its initial binding and uptake, which was saturable. Unlike its degradation within muscle cells, insulin was stable within HAMEC and escaped lysosomal colocalization. Insulin transcytosis required dynamin but was unaffected by caveolin-1 knockdown or cholesterol depletion. Instead, insulin transcytosis was significantly inhibited by both a clathrin-mediated endocytosis inhibitor and siRNA-mediated clathrin-depletion. Accordingly, insulin internalized for 1 minute in HAMEC colocalized with clathrin far more than with caveolin-1. This study constitutes the first evidence of vesicle-mediated insulin transcytosis and highlights that its initial uptake is clathrin-dependent and caveolae-independent.

Keywords: caveolae
clathrin
endothelial cell
insulin
TIRF
transcytosis
Advisor: Lee, Warren L
Klip, Amira
Factors of Identity Disturbance and Symptoms of Borderline Personality Disorder

Currently, there is a dearth of research investigating identity disturbance in borderline personality disorder (BPD). In this study, identity disturbance was hypothesized to encompass two lower order facets: Deficits in Narrative Construction and Deficits in Self-Reflection. Another purpose was to investigate how identity disturbance is related to two other symptoms of BPD: Emotion Dysregulation and Impulsivity. Participants were recruited and completed a series of self-report questionnaires and wrote four key life events. Overall, the two factors of identity disturbance were found, but the higher-order structure was not supported. A four oblique factor model of BPD traits fit the data best. Results indicated that Emotion Dysregulation, Impulsivity, and Deficits in Self-Reflection were all positively related to a measure of BPD symptoms, while Deficits in Narrative Construction was negatively related to this measure. Correlations among these factors are also discussed. The findings, limitations, and future directions of the study are discussed.

Keywords: Borderline Personality Disorder
Emotion Dysregulation
Identity Disturbance
Impulsivity
Narrative Construction
Self-Reflection
Advisor: Uliaszek, Amanda A
Evaluating Wood Fines as a Physical Conditioner for Dewatering Biosludge

Wood fines are sometimes used to improve biosludge dewatering and to supplement primary sludge, but how they improve biosludge dewaterability is not well understood. Wood fines (0-78% moisture content, dosages of 50-300%), and primary sludge fibres are added to biosludge, dewatered with a Crown Press, and evaluated with a mass balance. The wood fines used absorb on average 2.8ml of water per gram dry weight, which is more water than they help release. Thus, the increase in the dry solid content of the filter cake is primarily due the dry mass of the wood fines themselves, not an increase in water removal. Primary sludge fibres outperformed wood fines when evaluated on the Crown Press without a polymer, but the two conditioners performed similarly when a polymer was used. In a field study, wood fines are found to be an unsuitable physical conditioner when tested in a laboratory scale screw press.

Keywords: Biosludge
Dewatering
Physical Conditioner
Skeleton Builder
Waste Activated Sludge
Wood Fines
Advisor: Allen, D Grant
Tran, Honghi N