VictorJuiz/thesis huggingface dataset:
Revealing the Secrets of Small Talk: Can Adult Language Learners Be Taught This Sociolinguistic Skill?

The purpose of this study was to determine whether it is feasible to teach adult second language learners in instructional settings how to make small talk in a pragmatically appropriate manner. Making small talk is a way to express friendliness in English. It creates stronger social bonds between people (Laver, 1975; Malinowski, 1923). Newcomers can experience difficulty becoming socially integrated when they are not familiar with expected rituals, including how to make small talk. This study’s intervention was seven lessons on making small talk delivered to five adult learners of English in the greater Toronto area. The study’s data came from small talk interactions between participants and an actor. Learner performance on small talk measures improved after the intervention, interactions were shorter, and participants used a wider variety of common ground strategies including telling more stories. Implications for educators and policymakers include prioritizing the pragmatic competence of adult English learners.

Keywords: pre-test/post-test design
small talk
teaching
Advisor: Kerekes, Julie
Shifted-beam Array of Coils for Highly Focal Transcranial Magnetic Stimulation

Transcranial magnetic stimulation (TMS) is a non-invasive method of brain stimulation which uses electromagnetic induction to excite currents in the brain. This technique is useful in treating a wide range of psychiatric disorders and is extremely well-tolerated by patients. In neuroscience, TMS is also used as a tool for studying brain connectivity and mapping the cerebral cortex. The principal goal of TMS is to generate a focal E-field spot at a desired target region; however, this is greatly complicated by the physical properties of brain tissue as well as hardware limitations. As a result, highly focal TMS has remained an active area of research since the technique was first developed. This thesis presents a new method of TMS E-field focusing using principles based on shifted-beam antenna arrays, resulting in focality superior to effectively all currently realizable designs. Practical considerations for implementing the proposed designs are also discussed, as well as possible directions for future work.

Keywords: Brain stimulation
Coil design
Field focusing
Focality
Transcranial magnetic stimulation
Advisor: Eleftheriades, George
Simulations of Heat Current through Molecules

To understand and control energy transport at the scale of molecules, we study simple models of heat transport through hydrocarbons. We represent the system as 1-D harmonic chains and use Langevin baths to introduce the effect of the environment. Our first result is related to numeric computation of heat currents: We show that calculating the heat current between two atoms at the center of the chain reduces error relative to measuring heat current at the interface of the molecule and the heat baths. Our second result is a description of a new design of a thermal diode, using different thermal gradients at each end of the molecule instead of a single temperature. Unlike previously reported thermal rectifiers, our design operates in the limit of harmonic interparticle interactions.

Advisor: Segal, Dvira
Contraceptive Use and the Risk of Ovarian Cancer among Women with a BRCA1 or BRCA2 Mutation

BRCA mutation carriers face a high lifetime risk of developing ovarian cancer. Oral contraceptives are protective in this high-risk population; however, the impact of other types of contraception (e.g. intrauterine devices (IUDs), implants, injections) is unknown. This study evaluated the relationships between type of contraception and risk of developing ovarian cancer among women with a BRCA mutation. Ever use of any contraceptive was significantly associated with reduced risk of ovarian cancer, which was driven by significant inverse associations with oral contraceptives and implants. We observed a similar albeit non-significant effect with use of injections and IUDs. No significant associations were observed between patterns of IUD use and risk of ovarian cancer. These findings support a protective effect of oral contraceptives and implants on risk of ovarian cancer among women with a BRCA1 or BRCA2 mutation. The possible reduced risk with use of injections and IUDs requires further evaluation.

Keywords: BRCA
contraception
intrauterine device
ovarian cancer
risk factor
Advisor: Kotsopoulos, Joanne
Learning to Detect Slip Using Barometric Tactile Sensors

The ability to perceive object slip through tactile feedback allows humans to accomplish complex manipulation tasks. For robots, however, detecting key events such as slip from tactile information is a challenge. This work explores a learning-based method to detect slip using barometric tactile sensors that have many desirable properties; they are durable, highly reliable, and built from inexpensive components. We collect a novel dataset specifically targeted for robustness, and train a TCN to detect slip. The trained detector achieves an accuracy of greater than 91% on test data while displaying robustness to the speed and direction of the slip motion. When tested on two robot manipulation tasks involving a variety of common objects, our detector demonstrates generalization to previously unseen objects. This is the first time that barometric tactile-sensing technology, combined with data-driven learning, has been used for a manipulation task like slip detection.

Keywords: Deep Learning
Grasping
Perception for Grasping
Tactile Sensing
Advisor: Kelly, Jonathan S
Sleep Fragmentation, Astroglial Activation, and Cognitive Impairment in Older Adults

Alzheimer’s Disease (AD) and other dementias are a growing public health concern. Emerging evidence suggests that sleep disruption may contribute to the risk of dementia. In model organisms, sleep disruption can lead to astrocyte activation and impaired cognition. However, whether this is true in older humans is uncertain. We tested the hypothesis that sleep fragmentation is associated with astrocyte activation and downstream cognitive impairment. We used published human single nucleus RNA-seq data to identify marker genes for human activated astrocytes, and quantified the expression of these genes from bulk RNA-seq of dorsolateral prefrontal cortex tissue from 1080 older adults. We related this to antemortem sleep fragmentation measured by actigraphy and to cognitive function. Greater sleep fragmentation was associated with greater expression of activated astrocyte marker genes, which was in turn associated with worse cognition. This is compatible with the hypothesis that astrocyte activation may link sleep fragmentation to cognitive impairment.

Keywords: astrocyte activation
cognitive impairment
older adults
rna sequencing
sleep fragmentation
Advisor: Lim, Andrew SP
Molecular Doping of Conjugated Polymers

Described in this thesis are positive and negative molecular doping of conjugated polymers. These projects present various strategies to increase free charge carriers within a polymer-dopant system and investigate their structure-property relationships.Chapter one is a broad introduction of doping of organic semiconductors. This chapter defines what doping of organic semiconductors is and provides common examples of doping of conjugated polymers and organic semiconductors. Chapter two presents the first two strategies to increase electrical conductivity of polythiophene analogues. First, the heteroatom of poly(3-alkylchalcogenophenes) is changed from S to Se, to Te which impacts the doping efficiency. Secondly, the dopant counter anion size also impacts the doping efficiency. Morphology is discussed to explain theses trends. Chapter three investigates the negative-doping of poly(benzotriazole). This chapter explores the attempts and challenges of n-doping of negative-type homopolymers which includes using different types of dopants as well as synthetic routes to novel fluorinated of poly(benzotriazole)s.

Keywords: Conjugated polymers
Molecular doping
n-Doping
Organic semiconductors
p-Doping
Polychalcogenophenes
Advisor: Seferos, Dwight S
Optimizing Gestational Weight Gain in Twin Pregnancies

INTRODUCTION: Data on the optimal gestational weight gain (GWG) in twin pregnancies and the implications of inadequate GWG on pregnancy complications in this population are limited.OBJECTIVE: To evaluate the implications of inadequate GWG in twin pregnancies, identify the optimal range of GWG, and develop and implement a new care pathway aimed at optimizing GWG in this population. METHODS: We conducted the following separate (but strongly related) projects to address the objectives described above: (1) A systematic review and meta-analysis; (2) A retrospective cohort study; (3) A national survey among Canadian maternal-fetal-medicine specialists; (4) A new care pathway aimed at optimizing GWG in twins. RESULTS: (1) The meta-analysis revealed that over half (56.8%) of women with twins experience GWG outside of recommendations. Low-GWG was associated with preterm birth, while high-GWG was associated with preeclampsia. (2) Our retrospective study confirmed the findings of the meta-analysis in our local population. In addition, we identified new, outcome-based optimal GWG range in twins, which had better correlation with outcomes compared with current guidelines. (3) Through the survey we identified considerable inconsistencies and potential barriers for optimal GWG in twins; (4) We designed and implemented a new care pathway to optimize GWG in our Twins Clinic at Sunnybrook. CONCLUSIONS: GWG is an important and modifiable risk factor for preterm birth and other pregnancy complications in twin gestations, making its optimization an important goal of antenatal care in this population.

Keywords: Gestational Weight Gain
High Risk Pregnancy
Multiple Pregnancy
Obstetrics
Preterm Birth
Twin Pregnancy
Advisor: Melamed, Nir
Analysis of Biomarkers following an Aerobic Exercise Intervention for Individuals Recovering from Concussion

There is growing evidence documenting the beneficial effects of aerobic exercise following concussion, however, the biological underpinnings contributing to these positive outcomes are less well understood. To date, no empirical studies in humans have examined the exercise-mediated neurotrophic and neuroinflammatory responses following concussion. Therefore, the purpose of this thesis was to examine neurotrophic, inflammatory, and axonal injury blood biomarkers in those exposed to a structured aerobic exercise (AE) protocol and those exposed to a usual care (UC) protocol. No significant difference between the two groups were identified at 21-days post-injury (PI). Additionally, the change in blood biomarker concentrations from 7- to 21-days PI for all biomarkers analyzed was not significantly different between groups. These findings suggest that blood biomarker profiles do not appear to be significantly different between those exposed to structured aerobic exercise or usual care protocols acutely following concussion.

Keywords: Active Rehabilitation
Blood Biomarkers
Concussion
Concussion Management
Advisor: Hutchison, Michael G
Characterization and Relative Efficacy of Muscarinic Receptor Antagonism at the Hypoglossal Motor Nucleus to Block Inhibition of Tongue Motor Activity

The hypoglossal motor nucleus (HMN) is the origin of motor output to the tongue, with decreased activity in sleep precipitating obstructive sleep apnea (OSA) in humans. Our laboratory has identified that muscarinic receptor antagonism at the HMN increases tongue motor activity in sleep. A clinical study also showed that oxybutynin (a muscarinic receptor antagonist) combined with atomoxetine (a noradrenaline reuptake inhibitor) greatly reduced OSA severity; however, their site of action is unknown. Accordingly, we hypothesized that oxybutynin is an effective muscarinic receptor antagonist at the HMN, and characterized its relative efficacy with other muscarinic receptor antagonists. We recorded tongue muscle activity of anesthetized rats in response to the microperfusion of HMN with several muscarinic receptor antagonists during (i) muscarinic receptor stimulation and (ii) increased endogenous acetylcholine elicited by eserine. This thesis identifies that oxybutynin prevents tongue motor suppression due to increased endogenous acetylcholine by antagonizing muscarinic receptors at the HMN.

Keywords: Genioglossus
Hypoglossal
Muscarinic receptor
Obstructive sleep apnea
omadacycline
oxybutynin
Advisor: Horner, Richard L
Evaluating the Adequacy and Potential Use of Mental Health First Aid (MHFA) in Punjabi Communities

Mental health first aid (MHFA) is a psycho-educational intervention aimed at promoting mental health and training lay populations to intervene during mental health crises (Mental Health Commission of Canada, no date). Despite its increasing popularity, little research has been conducted into evaluating the adequacy of MHFA with ethno-racialized communities. Peel region, Ontario, is considered an ‘ethnic enclave’ for Canada’s South Asian migrant populations, with a distinctive presence of Punjabi communities (Qadeer, Agrawal and Lovell, 2010). This study critically considers the adequacy of MHFA and its application to Punjabi communities in Peel region. Through an approach based in Critical Race Theory (CRT), this study presents the obstacles and facilitators to MHFA, its perceived adequacy and use with an ultimate view to improving mental health outcomes for Punjabi communities. This study concludes that MHFA is generally perceived as adequate, its applicability is limited in the contexts of research participants.

Keywords: Brampton
Inequality
Mental Health
Mental Health First Aid
Peel
Punjabi
Advisor: Strudwick, Gillian G
Digital Algorithms for Quantized Analog Signal Processing

Quantized Analog (QA) signal processing is a technique which expands the input range of analog circuits by slicing the input signal into multiple portions, each processed by an independent signal path. This thesis presents digital algorithms in two domains of QA signal processing. First, an all-digital calibration technique utilizing the adaptive linear combiner is proposed to correct the QA amplifier front-end device mismatch. Second, we propose two algorithms to optimize the quantization levels. One is a global optimizer using the genetic algorithm. The other is a heuristic algorithm based on μ-law for faster simulations. Behavioural simulations show that both algorithms can produce non-uniform quantization levels that are superior to uniform levels and improve the signal-to-noise ratio (SNR) of the QA amplifier by at least 3 dB under a multitone input. For the first time, analog amplification is optimized considering the statistical characteristics of the signal.

Advisor: Liscidini, Antonio
Chan Carusone, Anthony
“A tug of war”: Perspectives on Masculinities in Canadian Men’s Ice Hockey

This study’s purpose was to explore masculinities in male university hockey players. A total of seven Canadian male university athletes participated in semi-structured interviews. The anonymous interviews covered experiences and perceptions of masculinity in hockey. Two types of masculinities were reportedly experienced. The first more salient form, resembled hegemonic masculinity, and reflected certain expectations and pressures for male hockey players to conform to. The second less dominant form, reflected a challenge to the hegemonic norm, characterised by respectful and inclusive qualities. These findings are interpreted to suggest that men may conform to hegemonic masculinity due to multiple factors, specifically external pressures. The embodiment of the secondary form of masculinity may be encouraged by factors such as team culture. These findings support recent literature highlighting the complicated relationship between hegemonic and competing masculinities. Future research is needed to identify enabling influences for male athletes to embody more progressive and positive masculinities.

Keywords: Athletes
Hegemonic masculinity
Ice Hockey
Male athletes
Masculinity
Sport
Advisor: Kerr, Gretchen
A Stochastic Programming Approach for Nurse Workforce Planning Under Uncertainty in a Hospital Context

Nurse workforce planning is a complex task due to the varying patient census and unknown nurse availability. We create a decision support tool to help hospitals proactively maintain an adequate nurse workforce while effectively utilizing the nursing budget. Using data from a large community hospital, we apply time series models to forecast future nurse termination and retirement. The forecasts are input into a risk-neutral two-stage stochastic programming model to minimize the total expected nursing costs and also to recommend hiring decisions for hospital inpatient units and the nurse resource team (NRT), under uncertain patient census and nurse absenteeism. We conduct sample average approximation (SAA) to estimate the upper and lower bounds for the minimal nursing cost of the planning horizon. We compare the results from our model with existing and heuristic nurse staffing methods and showcase the potential savings. Sensitivity tests are also performed to generate managerial insights.

Advisor: Carter, Michael
Characterizing the Inhibitory Effects of Specific Lactobacillaceae spp. on Highly Prevalent Bacterial Families in the Gut

The gut microbiota is a complex community of microorganisms that have varied influences on host physiology. By screening for microbe-microbe interactions, our lab found that some, but not all strains of Lactobacillaceae have a powerful inhibitory effect on bacteria from the S24-7 and Lachnospiraceae families – prevalent members of the gut microbiota. Despite a long history of being grouped together, many species within the family Lactobacillaceae are very genetically and functionally distinct from one another. My research has focused on determining how certain Lactobacillaceae species inhibit the growth of key gut bacteria, while others do not. This work is additionally important due to the fact that various lactobacilli are used as probiotics. I have demonstrated that the inhibitory effect is associated with acid production. This data characterizes antagonistic relationships between important members of the gut microbiota and emphasizes how the overall gut community may be influenced by these interactions.

Advisor: Navarre, William W
Building a Sparse Convolutional Neural Network Inference Accelerator on Field-programmable Gate Arrays

High computational complexity and large memory footprint hinder the adoption of convolution neural networks (CNNs) in latency sensitive applications, such as self-driving. The presence of many zeros in CNN parameters and intermediate results -- a phenomenon known as sparsity -- presents opportunities for hardware accelerators to circumvent these problems, leading to speed-up. Prior work on accelerating CNNs using field-programmable gate arrays (FPGAs) has mostly omitted the benefits from sparsity. The few exceptions either leverage sparsity only on fully-connected layers in CNNs, or scale poorly due to complicated datapath and control logic. In this thesis, we propose a fine-grained structured weight sparsity for accelerating CNNs on FPGAs with relative ease. To leverage this sparsity for CNN acceleration on FPGAs, we design a novel processing element (PE) and an end-to-end sparse CNN inference accelerator that arranges the PEs in a systolic-array. Our results show that pruning according to the proposed structured weight sparsity pattern can reduce the amount of multiply-accumulate (MAC) operations in VGG-16 and ResNet-50 v.1.5 by 3.34 fold and 2.69 fold, respectively, while keeping the top-1 validation accuracy on ImageNet within 5\%. When implemented on an Intel Arria 10 GX1150 FPGA, our sparse CNN inference accelerator can achieve 2.26 TOP/s and 1.17 TOP/s on the MAC operations in the pruned VGG-16 and ResNet-50 v1.5, respectively. These figures translate to 2.86 fold and 1.69 fold speed-up over a baseline accelerator that is agnostic to sparsity.

Keywords: Convolutional neural network
Field-programmable gate array
hardware acceleration
sparsity
Advisor: Brown, Stephen D.
Investigating the Determinants of Social Communication Differences in Neurodevelopmental Disorders

Social communication differences can negatively impact long-term outcomes for children and youth with autism spectrum disorder (ASD). There is evidence to suggest that demographic factors, IQ, sensory processing, attention, language, and repetitive, restrictive behaviours contribute to social communication. However, the determinants of social communication are studied independently of each other, and there is little consideration for the interplay between them. To address this literature gap, we used structural equation modelling techniques to understand the differential contribution of these factors to social communication in a combined sample of individuals with ASD, attention deficit hyperactivity disorder, as well as typically developing individuals. We found that a combination of factors, rather than one singular factor, contributed to social communication differences. Ultimately, by understanding the factors that contribute to social communication, we hope to be able to target specific skills or behaviours and to create personalized supports for individuals with ASD.

Keywords: autism spectrum disorder
neurodevelopmental disorders
social communication
structural equation modelling
Advisor: Kushki, Azadeh
Structural Characterization and Amelotin-mediated Mineralization of Enamel Lesions in Molar-incisor Hypomineralization

Background: Molar-incisor hypomineralization (MIH) is developmental dental defect characterized by demarcated opacities, commonly affecting first permanent molars and permanent incisors. Amelotin (AMTN) is an enamel-specific protein expressed during maturation stage of amelogenesis with mineral-inducing properties that makes it excellent candidate to treat MIH lesions.Objectives: To characterize ultrastructure of MIH-affected enamel; to explore the potential of AMTN in combination with hydroxyapatite (HA) particles for mineralization of MIH-affected enamel defects Methods: MIH teeth were collected and processed for light and scanning electron microscopy. MIH-affected regions were treated with AMTN in combination with HA followed by immersion in simulated body fluid. Results: MIH-affected enamel showed thinner rods and larger interrod spaces. AMTN-treated groups demonstrated increased net mineral gain along the rods with stronger resistance to brushing than the control groups. Conclusions: MIH-affected teeth showed porous microstructure, making them more prone to caries and enamel breakdown. AMTN demonstrated promising mineralizing properties translating to potential clinical treatment for enamel preservation in hypomineralization defects.

Advisor: Ganss, Bernhard BG
Carneiro, Karina KC
The Experience and Perceptions of Dental Students in Treating Adults with Developmental Disabilities

This study investigated the experience and perception of dental students with regards to treating Adults with Developmental Disabilities (AWDDs). Three groups were interviewed: experts, students who had no clinical training to treat AWDDs, and students who had completed their clinical training to treat AWDDs through a rotation at Mount Sinai Hospital (MSH) dental clinic. Motivations for working with AWDDs were described including health advocacy and social responsibility. The informal curriculum impacted the formation of student expectations. The rotation was described as a transformative learning experience. Alignment between students and experts suggested that the clinical training is adequate. The misalignment provided insight into areas for improvement. Additionally, a survey was sent out to the ten dental schools in Canada to quantify the number of clinical and didactic hours students receive in this subject matter. The survey showed a wide range of time dedicated to this subject matter across Canadian dental schools.

Keywords: Dentistry
disability
education
oral health
qualitative
special needs
Advisor: Dempster, Laura