title: Biomimetic Strategies for Electrophoretic Deposition of Polymers and Composites

contributor:
Zhitomirsky, Igor
Veldhuis, Stephen
Materials Science and Engineering

subject:
Electrophoretic deposition
Polymer films
Composite films
Corrosion protection
Bile acids
Biosurfactant

abstract:
The global market for fluoropolymers, including polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), is growing rapidly due to their copious applications in the construction, automotive, medical, chemical, and electrical industries. Fluoropolymers owe their popularity partly to their excellent chemical and thermal stability and useful mechanical, piezoelectric, and ferroelectric properties. They are made into films or coatings that are used for corrosion protection or surface property enhancement. Electrophoretic deposition (EPD) has generated increasing interest in manufacturing advanced films for various applications due to its low cost, versatility, simple apparatus, and good film quality compared with other deposition techniques like dip coating, spin coating, electrospinning, or spay coating. Moreover, EPD facilitates uniform deposition on the substrates of complex shapes at a high deposition rate.
The aim of this research is to develop novel biomimetic strategies for fabricating polymer films and their composite films with multifunctional particles through EPD. This method involves the electrophoresis of charged particles in a stable colloidal suspension towards an electrode, forming deposition. Fluoropolymers, however, are electrically neutral and chemically inert, and their EPD presents difficulties. Therefore, successful EPD depends on understanding how to modify the surface of polymer particles using advanced biosurfactants to impart charge and form a well dispersed, stable colloidal suspension.
One strategy is to leverage the unique dispersing power of bile acids and salts as biosurfactants for EPD of PTFE and PVDF films and composite films. When doing so, it was found that the amphiphilic structure of bile salts such as sodium deoxycholate (DChNa) facilitated adsorption on the chemically inert, hydrophobic surfaces of PTFE, diamond, and carbon dots. In this strategy, DChNa acted as a charging, dispersing, film-forming agent for the co-deposition of PTFE composite films from an aqueous suspension. Water insoluble bile acids (BAs) were found to be biosurfactants for the EPD of PTFE and PVDF from organic solvents, in which lithocholic acid (LCA) was used as a co-dispersant for the fabrication of composite PTFE-diamond coatings and PTFE coatings provided corrosion protection for stainless steel in 3% NaCl solutions. The dispersing performance of four other bile acids, chenodeoxycholic acid (CDCA), deoxycholic acid (DCA), ursodeoxycholic acid (UDCA), and cholic acid (ChA), was analyzed and compared with LCA on the deposition performance of PVDF. It was found that the PVDF deposition yield obtained using different BAs increased in the order of LCA<CDCA<DCA<UDCA<ChA. This was attributed to the difference in number, position, and orientation of OH groups in the structures of the BAs.
Another biomimetic strategy for the EPD of polymers and composites was inspired by the strong adsorption of mussel protein on rock surfaces in sea water. Catecholate-type molecules, caffeic acid (CA) and catechol violet (CV), were found to be biosurfactants for dispersing, charging, and depositing PVDF films and composites. Analyses of the deposition yield data, the chemical structure of the CA and CV, and the microstructure and composition of the films suggested that the aromatic rings on the CA and CV had hydrophobic interactions with the PVDF particles and that the phenolic groups formed bidentate chelating or bridging bonding to inorganic particle surfaces. The study demonstrated the feasibility of co-depositing PVDF with nanoparticles of TiO2, MnO2, and NiFe2O4. CA was also used for preparing PVDF-HFP particles and as a co-dispersant for the co-deposition of PVDF-HFP with NiFe2O4 and CuFe2O4 nanoparticles in order to make composite films that combine the ferrimagnetic properties of spinel ferrites with the multifunctional properties of ferroelectric polymers.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)


title: Natural Consumer Products as Candidates in Chemical Radioprotection

contributor: Radiation Sciences (Medical Physics/Radiation Biology)

abstract: This thesis examines select natural dietary compounds for their radioprotective properties in vitro. These compounds were selected on the basis of their use in the treatment of CFIDS (Chronic Fatigue Immune Dysfunction Syndrome). CFIDS in humans encompasses symptoms similar to those in ionizing radiation (IR) exposures. Therefore, compounds that address CFIDS symptoms might also have utility in dietary chemical radioprotection. Specifically, this thesis examines the radioprotective effects of plant metabolites –curcumin, andrographolide, d-limonene – and endogenous metabolites – phenylacetate, ursodeoxycholate, tauroursodeoxycholate – in clonogenic in vitro experiments. Compounds were examined for their radioprotective effects in p53 variant human colon carcinoma cells which share similar features to radiosensitive stem cells of the gastrointestinal tract. Experiments examined compounds on the basis of their chemoprotective, bystander inhibitory, radioprotective and radiomitigative properties. The d-limonene demonstrated notable chemoprotective properties as noted by the preferential toxicity to p53 defective cell lines. There were no compounds that exhibited bystander inhibitory effects. In acute high dose experiments, the phenylacetate demonstrated significant radioprotective effects up to 2 Gy with minor radioprotective effects from tauroursodeoxycholate at 0.5 Gy exposures. There were no compounds that demonstrated radiomitigative effects. Ultimately, this thesis demonstrates that natural consumer products in the treatment of IR-like syndromes provide an attractive basis on which to screen compounds the fields of radioprotection.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: From algorithm to cognition: Music acoustic features and their perceptual correlates

contributor:
Woolhouse, Matthew
Psychology

subject: music audio classification perception

abstract: Music preference research seeks to explain the relationship between music listeners and their music. An important task of such research is to describe differences between types of music. Musical genres are often chosen to address this task. But they are inadequate as they require subjective interpretation by both participants and researchers, making results difficult to decipher. This thesis provides foundational work to establish Music acoustic features (MAFs). MAFs are intended to provide a reliable method of music classification and description for experimental research. First, a labelled set of 4800 musical stimuli representing six MAFs of varying levels were systematically produced. A program tool, Essentia, was then used to identify low-level audio features within the musical stimuli that correlate with MAF manipulations. The Essentia features (EFs) that best represented MAFs were identified and used to predict MAFs in 44 real-world music clips. An online study also collected ratings from participants (N = 43) for each of the 44 real-world clips. The results of MAFs predicted by EFs and MAFs rated by participants were compared for consistency. The MAF Tempo correlated strongest between predicted and rated MAFs in real-world music, followed by Dynamic, Texture, Articulation, Register, and Timbre. Based on the outlined process, MAFs were to shown to be manipulable for experimental analysis, measurable within real-world stimuli, and readily perceivable by music listeners. These three criteria firmly establish MAFs as a reliable method of music classification and description for use in experimental research. Furthermore, the process outlined here can easily be adapted to validate other potential MAFs that may exist in music. MAFs will improve future research by increasing the robustness and clarity of conclusions, and thus provide greater insight into how and why people listen to certain types of music.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: This thesis aims to increase our understanding of music preference by helping us more accurately describe differences in music. Previous research has defined differences in music by genre categories, such as Classical or Dance music. However, genres are often subjective, and even arbitrary, in their descriptions. Instead of genre, this thesis proposes that a new method of categorization is used: Music Acoustic Features. These features are not subjectively defined, they can actually be measured within a piece of music. Furthermore, these features can be modified and tested in experiments to see how listeners respond. Such future experiments will provide us with a better understanding of what kind of music people like and why.


title: Additively Manufactured Hollow Coils for Stator Cooling in a Heavy-Duty Vehicle Axial Flux Permanent Magnet (AFPM) Propulsion Motor

contributor:
Emadi, Ali
Mechanical Design

subject: Motor Design

subject: Stator Cooling

subject: Electric Vehicle

abstract:
The growing demand of electrified light duty trucks, including sports utility vehicles (SUV) require high performance motors to surpass form their internal combustion engine counterparts. The Axial Flux Permanent Magnet (AFPM) Motor is expected to be one of the leading technologies to meet the demands of these industries due to its efficenct and high torque and power density. Designing a robust thermal management system for this motor is key to utilizing these performance benefits. To meet these demanding conditions, additive manufacturing is expected to play a critical role in enhancing performance. Additively manufactured hollow coil is a cooling strategy to extract heat directly from the hottest part of the motor, the stator. The following research assesses the viability of the design in a prototype motor. ANSYS CFX is used to characterize the pressure drop and flowrate, and a test setup is used to validate the results. The challenges associated with integrating the solution into a motor is highlighted as well as design issues during design development. Finally, the integration of a parallel hybrid SUV using an AFPM motor is documented and the challenges
with integration into a vehicle is explained.

abstract: Thesis

abstract: Master in Advanced Studies (MAS)


title: Globalism for Undergraduates: Pedagogies and Technologies of Global Education in the US and Canada

contributor:
O'Brien, Susie
English and Cultural Studies

subject: cultural studies, critical university studies, infrastructure, curriculum, global studies, social reproduction, empire, political economy, connectivity, racial capitalism, settler nationalism

abstract:
Examining contemporary higher education in the US and Canada, this study posits globalism as the reproductive condition for these postsecondary education systems and their infrastructures that has emerged within regional conditions of degraded institutional legitimacy and downgrading credentials. Across its chapters, university globalism is defined and cataloged via institutional practices that shape learning and labouring conditions for students, their surrounding environments, and the pedagogies administered to market and credential student experience. Chapters examine the global university, the global learning interface, the global curricular programme, the global student and the global classroom as multi-scalar sites for observing university globalism’s forms and their effects, especially on the situation of undergraduates. This formation is studied via infrastructuralism as an analytic shortcut to questions of social reproduction, political economy and their geohistories in these Global North contexts as globally dominant, mass cultural sites for global education.
I posit the framework of connectivity, defined as the social and infrastructural good through which globalism is variously represented and embedded into undergraduate study, to periodize this shared regional institutional culture from the 1990s to the present. Connectivity links higher ed’s digitalization with its cosmopolitan modes of networking, identity formation, and human capital development that emerge across the institutional spectrum in public pedagogies and curriculum studied herein. This infrastructure is managerial, extractive, and socially reproduced, conditioning ambivalence and pessimism into the institutionalist modes of learning, networking and credentialing promoted by university globalism. Connectivity’s pro-social ideologies of global citizenship, inclusive excellence and social innovation are analyzed against higher ed’s proletarianizing material conditions and its anti-social foundations in racial capitalism and settler nationalism within US and Canada. This study aims to illuminate global study’s contradictory terms for undergraduates alongside their organic intellectualism within university conditions, and their affordances for critical global pedagogical practice to meet the crises of the present.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: This dissertation examines globalism’s pedagogical and technological expressions in undergraduate student experience in the US and Canada. This study reads the global projects of these higher education systems as an infrastructure that conditions learning and credentialing as forms of anti-social, settler national and managerial self-development. By taking up the global connectivity era of the past three decades, this work brings digital infrastructures into dialogue with globalist education policies and administrative and disciplinary curricular projects in the context of degraded institutional legitimacy and downgrading credentials for undergraduates in these dominant inter/national sites for global education. It ultimately argues that the double binds produced by university globalism in these settings present a pedagogical occasion for abolitionist study in our time of planetary crises, unmasking the university as a knowable cultural object in a global cultural field and its infrastructure as a glitch-filled archive of relations of power, empire, and social reproduction.


title: FINITE ELEMENT ANALYSIS OF MECHANICAL BEHAVIOR OF MECHANICAL COMPONENTS UNDER COMPRESSION

contributor:
Wu, Peidong
Mechanical Engineering

subject:
Finite element analysis
Compression
Shear
Fracture
Ring compression
Johnson–Cook
Functionally graded material
Strain rate sensitivity
Hydrostatic pressure

abstract:
First, finite element analysis is used to numerically investigate the influence of superimposed hydrostatic pressure on ductility and fracture strain of compressed rings, using the ABAQUS/Explicit solver. As hydrostatic pressure increases, the stress state at the cross-section of the ring changes, and the tensile radial and tangential stress components become compressive. Decreasing stress triaxiality results in higher values of fracture strain. Radial stresses at the ring’s cross-section are more easily affected by hydrostatic pressure. The numerical results show that strain to fracture increases linearly with the hydrostatic pressure regardless of the shape factor or geometry of the rings.
Second, the effects of strain rate sensitivity on fracture of laminated rings under dynamic compressive loading are numerically investigated. Adding layers of rate-sensitive material at the outer wall enhances the ductility of the rings. The topographic arrangement and layer thickness play an important role in the crack initiation and propagation path. In the case of having layers of brittle materials inside the cross-section, the cracks initiate in the brittle layers first, from the inner layers at the cross-sections. When the layer thickness is relatively high, a delamination-like behavior occurs at the interface of hard and soft materials.
Third, responses of cubic shear–compression models are analyzed numerically. A set of approximate analytical relations are determined to obtain effective stress and effective strain of the material from the displacements of the gauge section and reaction force. A universal prediction model is determined, based on the analyses of 125 simulations, and its performance is tested. The predicted stress–strain curves are in good agreement with the input stress–strain curves of the material with an average error of approximately 3%. These numerical results set a basis for determining stress–strain curve of materials directly from the force–displacement curves of shear–compression tests.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: In this thesis, the finite element method (FEM) is utilized to investigate mechanical behavior and large plastic deformation of components under compression and different conditions. In the first and second parts of this work, the ABAQUS/Explicit package, and Johnson–Cook material and failure models are used to study the effects of superimposed hydrostatic pressure and cladding layers of rate-sensitive and rate-insensitive materials on ring compression test. Models of rings with different geometries and different topological arrangements of hard and soft materials will be used in the numerical simulations and the fracture mechanism of the rings under compressive loading will be investigated in detail. In the last part of this work, large plastic deformation at the gauge section of shear–compression models will be studied and a universal relationship for determining stress–strain curves of materials from the force–displacement curves of shear–compression tests will be obtained.


title: DOSIMETRIC COMPARISON OF THREE-DIMENSIONAL CONFORMAL RADIATION THERAPY (3D-CRT), INTENSITY MODULATED RADIATION THERAPY (IMRT) AND VOLUMETRIC MODULATED ARC THERAPY (VMAT) FOR DISTAL ESOPHAGEAL CANCER TREATED WITH EXTERNAL RADIATION

subject:
3D-CRT
VMAT
IMRT
Radiation Therapy
Dosimetry

abstract:
Purpose/Objectives:
Intensity Modulated Radiation Therapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT) provide advantages in delivery of radiation allowing conformality of delivered dose to the planning target and reducing dose to organs at risk (OAR), however, at the potential cost of low dose spread. Due to the central location of the esophagus and GE junction, dose to lungs, heart, spinal cord, liver, and kidneys must be considered. Low dose spread is of particular concern with respect to healthy lung tissue. This study comprehensively compares volumetric dose statistics of the standard three-dimensional conformal radiation therapy (3D-CRT) compared with VMAT and IMRT for distal esophageal cancer treatment.
Materials/Methods:
Forty patients who underwent pre-operative radiation therapy for esophageal cancer between 2012-2014 were retrieved from our database. Pinnacle planning software was used to create 3D-CRT, VMAT and IMRT radiation plans for all patients. Forty-five (45) Gy was prescribed for each patient with D95% > 42.75Gy for the planning target volume (PTV).  All plans were optimized to maintain PTV coverage while reducing dose to OAR with specific emphasis on lung and heart dose. Volumetric dose statistics were obtained, and Wilcoxon signed rank test was used to compare 3D-CRT vs IMRT and VMAT for Conformity Index, Integral Dose, Monitor Units, lung (V5Gy, V20Gy, mean, max), heart (V30Gy, mean, max), spinal cord max, bilateral kidneys (V20Gy, mean) and liver mean dose. Comparison was also made for IMRT vs VMAT.
Results:
For both IMRT and VMAT compared with 3D-CRT, statistically significant pairwise differences were noted for Conformity Index (-28.51%, -30.70%, P<.001), Integral Dose (-14.0%, -14.8%, P<.001), Monitor Units (107.2%, 80.4%, P<.001), lung (V20Gy: -49.7%,-57.4%, mean: -20.3%,-24.9%, P <.001), heart (V30Gy : -10.1%,-14.3%, mean -10.4%,-13.4%, P <.001), spinal cord (max 13.3%,9.5%, P <.001) and liver (mean  -29.9%,-24.3%, P <.001). No significant differences were noted for VMAT and IMRT compared with 3D-CRT for lung (V5Gy, max dose), heart (max dose) and bilateral kidneys (mean). VMAT did offer statistically significant improvement in Conformity Index, Monitor Units, lung V20Gy and mean dose as well as heart V30Gy and mean dose compared to IMRT.
Conclusion:
VMAT and IMRT offer excellent sparing of key organs (lung, heart) with respect to volumetric constraints. Max point doses as well as lung V5Gy, which can be an indication of low dose spread for esophageal treatment, were not conclusively different. While 3D-CRT offers acceptable treatment, VMAT should be the standard modality of radiation treatment where facilities exist.

abstract: Thesis

abstract: Master of Science (MSc)


title: REVERSE DIBLOCK COPOLYMER MICELLAR GROWTH OF DESIGNER NANOPARTICLES FOR ENHANCED SURFACES

contributor:
Turak, Ayse
Engineering Physics

subject:
nanofabrication
diblock copolymer lithography
templated nanoparticles

abstract: Diblock copolymers like poly(styrene)-block-poly(2-vinylpyridine) pave the way for controllable self-assembled monolayers of nanoparticles. Using particular polymer weights and concentration, spherical micelles of PS-b-P2VP can be constructed with a non-polar PS corona and a polar P2VP core. Various precursor salts can be loaded into the core of the micelles due to interactions with the polar core which forms as the active site for nanoparticle growth. The PS corona protects the core from the atmosphere and non-polar solvents. The micelles can then act as nanobeakers for aqueous chemistry in two ways; spontaneous reactions between precursors result in nanoparticles or the trapping of precursor salts can be oxidized or reduced using polymer removal techniques like gas plasmas. In this way, reverse micelles are a facile method of growing metal, metal oxide or dielectric nanoparticles. Process parameters, such as concentration, molecular weights, nature of solvents and type of precursor salt, offer control over the periodicity and size of the monolayer of nanoparticles. Reverse micelle templating is a potentially useful nanofabrication method for tailor-made nanoparticles for use in electrical and optical devices which is not limited to form-factor of substrates. In this thesis, obstacles are identified that hinder the utility of PS-b-P2VP templated nanoparticles in device fabrication. The polymer is insulating which is detrimental to electrical applications. Additionally, the characterization of a monolayer of polymers, thus far, is limited to structural techniques such as SEM and AFM. This thesis sheds light on the mechanism of precursor loading in the micelle core, discusses the efficiency of different polymer removal techniques and uses vibrational spectroscopy for the characterization of monolayers of polymer, loaded polymer and nanoparticles. We have tested enhanced Raman methods using AFM probes to extend the resolution of normal Raman to view monolayers of empty polymers as well. Moreover, using FeCl3-loaded polymer micelles, the control offered by PS-b-P2VP templated growth on the crystal structure of nanoparticles is laid bare. The usefulness of the technique is further divulged by using ordered gamma-Fe2O3 nanoparticles in water-splitting photoanodes where they show an increased efficiency with the inclusion of nanoparticles and their periodicity. This is just an example of devices using reverse micelle templated nanoparticles, paving the way for future applications. The flexibility of this method is further revealed by constructing self-assembled Au/SnO2 nanojunctions within the PS-b-P2VP micelle cores. This was done by exploiting the spontaneous redox reaction between HAuCl4 and SnCl2 in an aqueous environment, and so can be replicated for other metals and metal oxides like Pt, Pd, Ag, TiO2 and ZnO2. The composite nanoparticles formed exhibit a tunable size and dispersion as typically seen with PS-b-P2VP micelles and so, can be used for various applications which require metal/metal oxide junctions.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Assessing Lifestyle in Psychiatric Disorders

contributor:
Kapczinski, Flavio
Neuroscience

subject:
Depression
Anxiety
Bipolar Disorder
Lifestyle Psychiatry
Assessment

abstract:
Introduction: Major depressive disorder (MDD), generalized anxiety disorder (GAD), and bipolar disorder (BD) are mental illnesses associated with socio-cognitive functional impairments, reduced quality of life, and increased risk of medical and psychiatric comorbidities. These disorders are also associated with unhealthy patterns in several fundamental lifestyle areas according to the current notions of lifestyle psychiatry, such as diet, physical activity, substance use, sleep, stress management, and social relationships. With the rising prevalence rates of poor mental well-being following the onset of the COVID-19 pandemic, it is essential to understand the relationship between a multifactorial lifestyle and the presence of psychiatric symptoms. Thus, the aim of this thesis was to assess the association between a multidimensional lifestyle and symptoms of MDD and GAD during the COVID-19 pandemic, and lifestyle patterns among symptomatic individuals with BD. We additionally reviewed the literature on lifestyle interventions for improvement of outcomes related to BD.
Results: Unhealthy lifestyle behaviours were associated with symptoms of MDD and GAD during the COVID-19 pandemic in Spain, Brazil, and Canada. Machine learning analyses revealed strong predictive power for detecting the presence of these symptoms through lifestyle behaviours and perceptions. Individuals with BD engage in more unhealthy lifestyles than healthy individuals across all the core areas of lifestyle psychiatry, regardless of the polarity of the mood episode. Furthermore, to date, traditional lifestyle domains such as diet, physical activity, and sleep have been the most frequently targeted domains for interventions to improve mood symptoms and functional outcomes of BD, while domains such as substance use, stress management and social relationships have been more neglected. In addition, multidimensional lifestyle interventions have demonstrated a higher efficacy rate of improving outcomes of BD than single-domain interventions, however, there has been a lack of interventions for BD targeting majority of the core lifestyle domains.
Conclusion: The findings suggest that multidimensional unhealthy lifestyles are associated with symptoms of MDD, GAD, and BD. These results support the current notions of lifestyle psychiatry, indicating that a multidimensional assessment of lifestyle behaviours and perceptions can be a beneficial approach towards understanding the cumulative impact of various lifestyle patterns on psychiatric symptoms. This work highlights the importance of imposing a holistic approach towards studying the association between lifestyle factors and psychiatric disorders in order to implement effective, personalized preventive and treatment strategies for mental health disorders.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: People experiencing symptoms of psychiatric disorders may also engage in more unhealthy routines and behaviours in everyday life. Lifestyle is a construct characterized by behaviours and perceptions in multiple areas of life which are fundamental for the overall well-being of a person. The aim of this thesis was to investigate the relationship between multidimensional lifestyle characteristics and symptoms of depression, anxiety, and bipolar disorder (BD). We examined the association between multidimensional lifestyle and symptoms of depression and anxiety in the general populations of Spain, Brazil, and Canada during the COVID-19 pandemic. We also assessed the relationship between unhealthy behaviours and symptomatic individuals with BD in comparison to healthy individuals, and the importance of lifestyle interventions for improvement of outcomes related to BD. The findings indicated an association between multidimensional unhealthy lifestyles and symptoms of depression and anxiety during COVID-19. Unhealthy lifestyles across all domains were also seen in people with BD currently experiencing a mood episode, while lifestyle interventions for BD have shown promising results so far. A multidimensional approach to evaluating quality of lifestyle can be beneficial for developing preventive and treatment lifestyle strategies for common psychiatric disorders.


title: Physiotherapy and Point of Care Ultrasonography

title: Point of Care Ultrasonography in Physiotherapy Research and Practice

contributor:
Solomon, Patricia
Rehabilitation Science

subject:
physiotherapy
point of care ultrasonography
rehabilitation
diagnostic ultrasound

abstract:
Point of care ultrasonography (POCUS) is a non-ionizing imaging modality that is performed and interpreted by a primary health care professional in combination with a physical examination in a clinical setting. POCUS can provide time sensitive clinical information to assist in diagnosis of pathology and to monitor response to treatment. POCUS is emerging in physiotherapy clinical practice, education, and research. This dissertation explores physiotherapist performed POCUS and consists of two scoping reviews and an inter-professional agreement study.
The first scoping review systematically mapped the research literature to describe the breadth and depth of physiotherapists performed POCUS. Two hundred and nine studies were included, and the majority of the included studies were measurement studies that assessed the psychometric properties of POCUS in adult patients, were published in the United States of America, and imaged the abdominal lumbo-pelvic region. POCUS was found to be a recent application of sonography in physiotherapy practice. This review identified a wide variety of practice settings and a diverse number of patient conditions in which physiotherapists are performing POCUS. This breadth and depth of this review highlighted the need for improved reporting of study methodology and key areas of future research in physiotherapist performed POCUS.
The second scoping review explored physiotherapy pre- and post-licensure curricula and pedagogical approaches for POCUS. Fifteen studies were identified. These showed that progress in the development of physiotherapy-specific, competency based, standardized education curricula and pedagogical approaches for POCUS has been limited. There was considerable variability both pre- and post licensure and further research is needed to assess the outcomes of different pedagogical approaches on theoretical knowledge and practical scanning competence. There is a need for internationally accepted terminology for physiotherapist performed POCUS and clear guidelines from local regulatory colleges and licensing bodies.
The third study was an inter-professional agreement pilot study between a physiotherapist and a sonographer for the assessment of acute hemarthrosis in 13 patients with hemophilia using POCUS. In this study, the physiotherapist participated in the McMaster University Mohawk College POCUS Training Program for Acute Hemarthrosis and Synovitis. The results indicated a high level of agreement between the physiotherapist and the sonographer performed POCUS for the binary decision on the presence or absence of blood within the joint. The physiotherapist-acquired images demonstrated quality comparable to an expert sonographer. This study provides support that following a short formal training program, a trained physiotherapist can become proficient in the acquisition and interpretation of POCUS images for the assessment of hemarthrosis in patients with hemophilia.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)

abstract: Point of care ultrasound (POCUS) is an ultrasound scan that is performed by a health professional in a clinical setting. Physiotherapists are increasingly using POCUS in clinical practice and research. This thesis explores physiotherapist performed POCUS to address important gaps in knowledge to: (1) describe where physiotherapists are using POCUS, with which patients, and for what purpose; (2) describe the different types of training and education that physiotherapists received to perform POCUS; and (3) to compare a physiotherapist trained in POCUS to an expert sonographer in the performance and interpretation of POCUS scans for the assessment of joint bleeding in patients with a bleeding disorder called hemophilia. The findings of this thesis can inform future studies on education, training, and experience of physiotherapists using POCUS, and lends support to the integration of POCUS into physiotherapy practice with different patient populations and conditions.


title: BIOMARKERS OF COAGULATION, ENDOTHELIAL DYSFUNCTION, AND FIBRINOLYSIS IN PATIENTS WITH COVID-19

contributor: Medical Sciences (Thrombosis & Haemostasis & Atherosclerosis)

subject:
COAGULATION
COVID-19
FIBRINOLYSIS
ENDOTHELIAL DYSFUNCTION

abstract:
Immunothrombosis and coagulopathy in lung microvasculature may lead to lung injury and disease progression in severe COVID-19. However, the mechanism that leads to decompensation and death for some patients, thus delineating them from patients who recover and survive, is poorly understood. We aim to identify biomarkers of coagulation, endothelial function, and fibrinolysis that are associated with disease severity and may have prognostic potential.
Our study has explored four different cohorts: 1) our pilot cohort, 2) COVID-BEACONS study cohort, 3) CanCOV study cohort and 4) ACTIV-4A trial cohort. The patient plasmas from these samples were quantified using 1) ELISAs for plasminogen, soluble thrombomodulin (sTM), plasminogen activator inhibitor-1 (PAI-1), α2-antiplasmin (A2AP), thrombin antithrombin complex (TAT), D-dimer, thrombin-activatable fibrinolysis inhibitor (TAFI), and fibrinogen, and 2) in-house functional assays for clot lysis times and activated TAFI (TAFIa) levels. Biomarker values were log-transformed and linear mixed effects models were used to compare trajectories in ICU and ward patients compared to outpatients from date of symptom onset.
Our pilot cohort showed that sTM, PAI-1, plasminogen and clot lysis times have predictive ability for mortality. In order to validate these findings, we explored the other three cohorts. The COVID-BEACONS cohort confirmed that plasminogen is associated with death and showed that fibrinogen and TAFI levels also predicted mortality in the COVID-19 patients. In the CanCOV study cohort, D-dimer and sTM antigen levels showed the strongest associations with moderate and severe COVID-19 compared to mild disease. PAI-1, plasminogen, TAFIa, and fibrinogen may additionally be useful in identifying patients who become critically ill. Lastly, the ACTIV-4A trial cohort showed an increase in PAI-1, sTM and TAFIa levels in COVID-19 outpatients, whereas a longitudinal decrease in the antigen levels of fibrinogen and A2AP was observed.
The data from the cohorts needs to be normalized using clinical data and symptom onset data, and then used to validate the findings of our pilot cohort. Once that is achieved, our study has the potential to identify biomarkers that can predict which patients are likely to be severe and worsen over time, which could lead to early treatment and better chance of survival.

abstract: Thesis

abstract: Master of Science in Medical Sciences (MSMS)

abstract: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for the coronavirus disease-2019 (COVID-19) pandemic. COVID-19 presents as a respiratory tract infection, with severe cases causing substantial damage to the lungs as well as its surrounding blood vessels. The cause of death in COVID-19 is thought to be a consequence of lung and multiple organ injury resulting from a hyper-immune response to the virus, leading to a vicious cycle of cell damage and hyperactive blood clotting. However, why some patients worsen over time that could potentially lead to death while others recover remains uncertain. Our study aims to measure the circulating levels of various proteins that are involved in the formation and removal of blood clots over the course of the disease. Identifying which of these proteins can predict those that are likely to become severely ill could lead to early intervention for better outcome and survival.


title: Label-Free Magnetic-Field-Assisted Fabrication of Cellular Structures

contributor:
Puri, Ishwar K.
Biomedical Engineering

subject:
magnetic field
paramagnetism
cell migration
wound healing assay
in vitro
layer-on-layer
3D cell culture

abstract: Controlled cell assembly is essential for fabricating in vitro models that mimic native tissue architecture. Conventional tissue engineering techniques are time-consuming and offer limited control over the spatial organization of cells within the assembled cell aggregates. We describe a label-free, scaffold-free, rapid cell manipulation technique to assemble cells into layered aggregates. Suspensions of cells in a culture medium with higher magnetic susceptibility are seeded into wells of a 96-well plate placed on a quartet magnet array. An FDA-approved paramagnetic agent is added to the regular cell culture medium to enhance the magnetic susceptibility. The inhomogeneous magnetic field and the susceptibility difference drive cells toward the lowest magnetic field region on the well surface. Two cell types are sequentially added to the wells to form layer-on-layer aggregates within 6 h. Next, the label-free technique is extended to develop a cell migration assay. Besides being time-consuming, the traditional scratch-based cell migration assay is not reproducible, whereas the alternate physical barrier-based method is expensive. Annular aggregates of human bronchial epithelial cells (HBEC3 KT) are formed within 3 h using a coaxially arranged ring-cylinder magnet array. The effects of the paramagnetic agent on cell viability, metabolism, and transcriptional profiles are investigated. The closures of the circular cell-free areas enclosed by HBEC3 KT are analyzed at different times in response to various signaling molecules and surface conditions. Further, we demonstrate the formation of the annular aggregates on human lung fibroblast-laden collagen hydrogel surfaces. The cell-free area closures on hydrogel surfaces in response to signaling molecules are analyzed. The high reproducibility and scalability of the label-free method make it amenable for preclinical research.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: Cell cultures are essential tools for studying cell functions under controlled conditions. A better understanding of cell behavior in tissues is required to develop effective treatments for diseases. The organized arrangement of cells in tissues controls tissue functions. The existing culture techniques are time-consuming and have limited control over the cellular arrangement. We describe a simple, rapid, and inexpensive bioprinting technique to arrange cells in layers, which resembles the cellular organization in tissues, such as the skin. The layered structures are formed in standard well plates within 6 h. Cell movement is an essential cell function in various biological processes, such as wound healing. Using the bioprinting method, we form ring-shaped cellular structures within 3 h to study cell movements in response to various signals. The ring structures enclose cell-free areas, which are populated over time as the cells move from the ring into the cell-free regions. The bioprinting method is easy to use and can rapidly form organized cellular structures for drug testing.


title: Applications of Deep Learning to Video Enhancement

contributor:
Chen, Jun
Electrical and Computer Engineering

subject:
Video Enhancement
Deep Learning

abstract:
Deep learning, usually built upon artificial neural networks, was proposed in 1943, but poor computational capability restricted its development at that time. With the advancement of computer architecture and chip design, deep learning gains sufficient computational power and has revolutionized many areas in computer vision. As a fundamental research area of computer vision, video enhancement often serves as the first step of many modern vision systems and facilitates numerous downstream vision tasks. This thesis provides a comprehensive study of video enhancement, especially in the sense of video frame interpolation and space-time video super-resolution.
For video frame interpolation, two novel methods, named GDConvNet and VFIT, are proposed. In GDConvNet, a novel mechanism named generalized deformable convolution is introduced in order to overcome the inaccuracy flow estimation issue in the flow-based methods and the rigidity issue of kernel shape in the kernel-based methods. This mechanism can effectively learn motion information in a data-driven manner and freely select sampling points in space-time. Our GDConvNet, built upon this mechanism, is shown to achieve state-of-the-art performance. As for VFIT, the concept of local attention is firstly introduced to video interpolation, and a novel space-time separation window-based self-attention scheme is further devised, which not only saves costs but acts as a regularization term to improve the performance.
Based on the new scheme, VFIT is presented as the first Transformer-based video frame interpolation framework. In addition, a multi-scale frame synthesis scheme is developed to fully realize the potential of Transformers. Extensive experiments on a variety of benchmark datasets demonstrate the superiority and liability of VFIT.
For space-time video super-resolution, a novel unconstrained space-time video super-resolution network is proposed to solve the common issues of the existing methods that either fail to explore the intrinsic relationship between temporal and spatial information or lack flexibility in the choice of final temporal/spatial resolution. To this end, several new ideas are introduced, such as integration of multi-level representations and generalized pixshuffle. Various experiments validate the proposed method in terms of its complete freedom in choosing output resolution, as well as superior performance over the state-of-the-art methods.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Binary Codes for Enhancing the Most Significant Bit-Based Selective Encryption

contributor:
Dumitrescu, Sorina
Electrical and Computer Engineering

subject: Selective Encryption, Most Significant Bit, Binary Code, Uncompressed Images, Compressed Images

abstract:
Selective encryption (SE) methods for images often encrypt the sign bits, i.e., the most significant bits (MSBs) of the codewords corresponding to key syntax elements (in compressed images) or to pixel intensities (for uncompressed images). Our work is motivated by the key observation that the binary code (BC) used for these representations has an impact on the quality of the reconstruction at the eavesdropper (Eve), which can be regarded as a measure of the degree of security of the encryption (the lower the quality, the higher the level of security). Therefore, we address the design of BCs that enhance the security of MSB-based SE by increasing the degradation at Eve’s side when she uses a simple replacement attack (replacing all MSBs either by 0s or by 1s). We first consider the scenario of fixed-length BCs, i.e., where all the codewords have the same length. We formulate the design problem as an optimization problem with the objective of maximizing the distortion at Eve’s without any constraint or with a constraint on the entropy of the MSBs in order to shorten the size of the MSB stream to reduce the computational overhead of encryption. We show that the problem can be cast as a binary integer linear program equivalent to a weighted non-bipartite graph matching problem, for which polynomial-time solution algorithms exist. We empirically assess the performance of the optimized BCs on a Mixed Gaussian source, as well as on Gaussian and Laplacian sources, the
latter two being commonly used to model the distribution of transform coefficients and prediction residuals. Our experiments lead to the conclusion that MSB-based SE schemes could benefit from the proposed BC designs. For the case of uncompressed images, we also propose a family of structured BCs for the pixel intensity values. These BCs are constructed such that intensity values that are close have reconstructions that are far apart. As a result, the reconstruction with the replacement attack significantly destroys the smooth areas and blurs the edges, therefore increasing the degree of security. Next, we focus on the construction of variable-length BCs for the non-zero quantized AC coefficients in JPEG compressed images. For this, we first formulate the BC design problem as the problem of maximizing the distortion at Eve’s side with a constraint on the entropy. This problem can also be cast as a weighted non-bipartite graph matching problem and, therefore, can be solved efficiently. Furthermore, by gaining insights from the optimization results, a simpler and faster method for BC design is devised, which consists of only swapping a few codewords in the original code used in JPEG. We assess the practical performance of the proposed BCs for the SE method of JPEG images that encrypts only the MSBs of the non-zero quantized AC coefficients, along with the full encryption of the DC coefficients. Our experimental results show that high visual security can be achieved with only a small sacrifice in compression efficiency. In addition, the proposed BCs can be tuned to achieve various levels of degradation at Eve’s side, a property that is convenient for certain applications.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: NMR Study on Silicon Anode Material for Lithium-Ion Batteries

contributor:
Goward, Gillian
Chemistry

abstract:
This research aims to explore material questions within the field of lithium-ion batteries (LIBs) used for electric vehicles (EVs) through nuclear magnetic resonance (NMR). In EVs, the driving range and fast-charging capabilities need improvement. A promising anode material, silicon, was investigated using both ex situ and operando NMR techniques. Ex situ 7Li NMR was used to identify key lithium silicide phases in the material at various states of charge (SoC). The different phases highlighted throughout this report represent the degree of lithiation per silicon atom. The longevity of the silicon material was tested as a function of cycle count, which provided insight into how the different local environments in silicon were affected. Based on the ex situ 7Li NMR results, mechanisms
for capacity fade and degradation were proposed.
                                                                                Operando NMR allowed for the silicon material to be monitored simultaneously with the electrochemical charging cycle. Real-time information regarding structural changes of the LixSi phase under multiple different cycling conditions was achieved and analysed based on deconvolutions and integration. The slower charging rate (C-rate) of C/3 using operando NMR further confirms the formation of phase 1 (LixSi, x < 2.0) and phase 2 (LixSi, 2.0 < x < 3.5) seen via ex situ NMR. More detail was provided with this technique than an ex situ spectrum collected at the top of charge (TOC) and bottom of discharge (BOD) of the post-mortem battery. When the current density of the battery was increased, drastic differences were seen regarding the formation of lithium silicide phases in comparison to slower c-rates. With the faster C-rates, lithium metal was formed during the NMR experiment, and the formation of phase 3, a more highly lithiated crystallin phase, not present under ex situ conditions, was identified. This one-of-a-kind methodology allowed us to probe the lithium environments in the silicon anode material and gain insight into fundamental chemical changes that occur during battery operation.

abstract: Thesis

abstract: Master of Science (MSc)

abstract:
In recent years, the demand for alternative energy storage devices has grown. Specifically, lithium-ion batteries have become a technology of interest in the automotive industry. The widespread electrification of vehicles will reduce greenhouse gas emissions and thus promote a cleaner energy future. However, the primary challenges that hinder electric vehicles are a comparable driving range to that of a traditional fossil fuel-burning engine and fast-charging capabilities.This work demonstrates how different cycling conditions affect the negative electrode (anode) of the battery with the use of nuclear magnetic resonance (NMR) techniques.
Longevity studies were carried out with silicon as the negative electrode, and insights into different lithium silicide phases depending on the state of charge (SoC) and cycling count were discovered. This comprehensive work supports previously published results describing the capacity fade and breakdown mechanisms of silicon and is the first to acquire NMR spectra at advanced cycle counts. In addition, more crystalline lithium silicides are formed at faster charging rates, and the presence of lithium metal is
detected, which can be detrimental to the battery's health. The behaviour of lithium chemical environments within the silicon anode material is quantified, providing an in-depth interpretation of the result. The performance of silicon under different conditions, like those seen in an electric vehicle, ultimately indicates how different current rates
affect the material and leads to the classification of different chemical environments within the material of interest.


title: Exploring the Contextual Determinants of Vaccine Acceptability

contributor:
Christy, Gombay
Laura, Banfield
Global Health

subject:
Vaccine Acceptability
Vaccine Hesitancy

abstract: Background: Poor demand for vaccines has long been recognized as a threat to the realization of public and global health objectives. Consequently, over time a range of interventions have been researched, proposed, and implemented in an attempt to improve the acceptability of vaccines and overcome vaccine resistance. However, much of the contemporary research concentrates disproportionately on individual-level determinants as viable targets for interventions. This disparate focus on individual-level factors has seemingly been at the expense of research into fundamental contextual influences. As a result, the primary aim of this thesis is to explore and develop a greater understanding of the contextual determinants of vaccine acceptability and their evolution over time and across different global contexts. Furthermore, emerging themes will be analyzed in an effort to explore how different contextual determinants work together or separately to influence vaccine acceptability. Methodology: The methodological approach adopted for this thesis concentrated on enabling and conducting an in-depth literature review of the contextual determinants of vaccine acceptability. To begin, a concept analysis was conducted to inform the design, focus, and implementation of a literature review. Subsequently, an in-depth literature review of research derived from the Global Health database was conducted using relevant papers published between 1910 and 2022. Data related to publication and content characteristics were extracted to support the analysis process and discussion. Ultimately themes related to the seven contextual determinants categories were identified, extracted, and analyzed. Results: Through the final analysis, 32, often interrelated themes were identified across the seven contextual determinant categories. The determinant category of Politics & Policy was found to be relevant in 70.5% (n=98) of articles included in this literature review. Religious, Social & Cultural determinants were relevant in 53.24% (n=74) of articles, followed by Communication & Media Environment at 43.16% (n=60), Influential Leaders at 41.37% (n=58), History & Historical Factors at 38.13% (n=53), Pharmaceutical Influences at 24.46% (n=34), and Geographic Influences at 18.7% (n=26). Conclusion: The acceptability of vaccines is undoubtedly influenced by the broader factors that shape the contexts in which vaccines are delivered. Additionally, these contextual determinants are likely to interact with, or influence the many commonly referenced putative individual-level determinants of vaccine acceptability. As a result, the complex nature of any relevant contextual determinants should be considered in the design of efforts aimed at promoting or improving demand for vaccines.

abstract: Thesis

abstract: Master of Science (MSc)

abstract: The contextual determinants of vaccine acceptability have been seemingly under- researched relative to other individual-level factors. As a result, this thesis aims to explore and develop a greater understanding of the contextual determinants of vaccine acceptability and their evolution over time and across different global contexts. To achieve this objective, an in-depth literature review of 139 identified articles was conducted in an effort to explore and identify themes related to the contextual determinant of vaccine acceptability. Ultimately, through this review 32 themes across the seven contextual determinant categories were identified and discussed. These findings helped elucidate the complex and fundamental role that contextual determinants have in shaping demand for vaccines.


title: Route Navigation and Driving: Role of Visual Cues, Vestibular Cues, Visual Spatial Abilities, Age and Mood Disorders

contributor:
Shedden, Judith
Psychology

subject:
Driving Simulator
Proximal and Distal Landmarks
Route Navigation
Wayfinding
Vestibular Cues
Individual Differences

abstract: The studies reported in this thesis aim to provide insights on the process of navigation while driving. Driving requires processing and monitoring multiple tasks and sources of information. Navigation while driving increases the cognitive load of the driving task. Offloading the task of navigation to navigation aid systems such as GPS has potential disadvantages for our spatial memory skills. In this thesis, we introduce useful cues and skills to improve the performance of drivers in a variety of situations where they must navigate without the help of GPS. We used a motion simulator with six degrees of freedom to simulate various virtual reality driving scenarios that combine both visual and vestibular cues. In the following chapters, we report the effects of landmark cues, vestibular cues, self-reported mood disorders (e.g., depression, anxiety, and stress), individual differences at the visual spatial level (e.g., working memory span and mental rotation skills), age, and self-reported navigation skills on drivers’ route learning. We showed that successful navigation in various navigational situations depends on the type of landmarks available in the environment and the specific visual-spatial skills of drivers. We showed that vestibular self-motion cues improve egocentric route learning. Depression, anxiety, and stress affected drivers' route learning ability and dependency on GPS. We observed no deficit in age-related navigation performance when older drivers were able to use an egocentric frame of reference, however there was less optimal navigation performance of older drivers when wayfinding required an allocentric frame of reference. Overall, the application of the findings of this thesis may lead to an increase in efficacy and success in navigation performance and wayfinding while driving.

abstract: Thesis

abstract: Candidate in Philosophy

abstract: This thesis focuses on enhancing our understanding of wayfinding while driving in young and older adults. Using a driving simulator, we ran various virtual reality experiments to examine the underlying mechanisms of navigation while driving and ways to improve wayfinding of drivers. We identified useful cues for route learning in different environments where there were no navigation aid systems. We examined correlations between various spatial skills and performance that may improve drivers' wayfinding in unfamiliar environments. Furthermore, we assessed age-related effects on route learning and potential interventions to improve navigation in older drivers. The findings from the experiments reported in this thesis introduce the principle of route learning while driving in terms of how various internal and external factors can affect it. Drivers can incorporate these findings into their navigation tasks to overcome the wayfinding challenges that they encounter when driving in unfamiliar environments.


title: Recent Synthetic and Structural Developments in Noble-Gas, Chlorine, Bromine, Iridium, and Group 6 Fluorine Chemistry

contributor:
Schrobilgen, Gary J.
Chemistry and Chemical Biology

abstract:
The candidate’s Ph.D. Thesis research exploits the fluorides of the noble-gases, chlorine, iridium, and the Group 6 oxide tetrafluorides to address specific knowledge gaps in fundamental inorganic fluorine chemistry. The compounds dealt with in these studies are potent oxidants that are extremely air-sensitive. Structural characterization methods included low-temperature (LT) Raman spectroscopy and LT single-crystal X-ray diffraction (SCXRD). Quantum-chemical calculations were used to aid vibrational mode assignments and to assess bonding.

A goal of this research was to address the absence of mixed Xe(II)/Kr(II) and Xe(IV)/Kr(II) noble-gas compounds. This led to a synthetic, structural, and computational study of the first mixed Kr(II)/Xe(II) species, the [FKrFXeF]+ cation (as the [AsF6]– salt), and the first mixed Kr(II)/Xe(IV) compounds, obtained as the cocrystals ([Kr2F3][AsF6])2∙XeF4 and XeF4∙KrF2 that were isolated at LT from anhydrous HF (aHF) solvent.

Although the fluoride-ion donor chemistries of the neutral X(V) (X = Cl, Br) fluorides and oxide fluorides are developed, the coordination chemistries of the X(V) cations [XF4]+, [XOF2]+, and [XO2]+ were largely unknown. The synthesis and structural characterization of the first Cl(V) coordination complex of XeF2, [O2Cl(FXeF)2][AsF6], is described. The reaction of α-[ClO2][AsF6] with XeF2 at −78 °C in anhydrous HF (aHF) solvent yields [O2Cl(FXeF)2][AsF6], which constitutes a rare example of noble-gas difluoride coordination to a main-group Lewis acid center. In a related study, the reactions of [BrO2][PnF6] with XeF2 in aHF were shown to yield [O2Br(FXeF)n][AsF6] (n = 1, 2) and [O2Br(FXeF)2][SbF6]. The complexes were characterized by LT Raman spectroscopy and SCXRD and provided the first examples of coordination complexes between a noble-gas difluoride and [BrO2]+.

Another goal was to synthesize and structurally characterize the first example of an iridium oxyfluoride. The study focused on the reaction of IrO2 with the oxidative fluorinaters, ClF5 and ClF3, which yielded the Ir(V) complex, F5Ir---OClF and the first iridium oxyfluoro-anion salt, [ClO2]2[cyclo-(µ-OIrF4)3], where the iridium atoms are in the +5 (x2) and +6 oxidation states. This study also provided the first crystallographic characterization of endothermic OClF.

At the outset of this research NgF2 (Ng = Kr, Xe) were known to form complexes with the intermediate-strength fluoride-ion acceptors, MOF4 (M = Cr, Mo, W), having the formulae NgF2·nMOF4 (n = 1, 2). However, FKrFb---WOF4 and FKrFb---MOF3Fbʹ---MOF4ʹ (M = Mo, W) defied characterization by SCXRD because they rapidly underwent redox decomposition during attempts to grow crystals. The syntheses and structural characterizations of FKrFb---WOF4 and the HF solvate, [--(F4OMo)(µ3-F)H---(µ-F)H--]∞, are described. The only TM complex of XeF4, F3XeFb---WOF4, was also synthesized and structurally characterized. Prior to this work, XeF4 coordination chemistry was limited to [Mg(XeF2)(XeF4)][AsF6]2, where XeF4 is F-coordinated to Mg2+.

The reactions of MOF4 (M = Cr, Mo, W) with XeF6 were also studied with the aim to synthesize high-oxidation-state Group 6 oxyfluoro-anion salts of [XeF5]+ and [Xe2F11]+. Room-temperature reactions of XeF6 and CrOF4 in aHF and CFCl3 led to reductive elimination of F2 and the novel Cr(V) oxyfluoro-anion salts, [XeF5]2[Cr2O2F8]·2XeOF4 and [XeF5]2[Cr2O2F8]·2HF. The reaction of CrO2F2 and XeF6 gave [XeF5][Cr2O4F6], [XeF5][Cr2O4F6]·4HF, [XeF5][Cr2O4F6]·2XeOF4, and [XeF5][Xe2F11][CrO2F4], which provide the first crystallographically characterized Cr(VI) oxyfluoro-anions derived from CrO2F2. Reactions of MOF4 (M = Mo, W) with XeF6 in aHF solvent yielded [XeF5][M2O2F9] and [Xe2F11][MOF5],  whereas the LT reaction of XeF6 and CrOF4 in aHF yielded [XeF5][HF2]·CrOF4. To circumvent [HF2]− formation, [Xe2F11][CrOF5] was synthesized in ClF2CCF2Cl (Freon-114), which provided the first SCXRD characterization of a [CrOF5]− salt.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: This Body is Without a Head: The Dilemma of Free Will and Social Cohesion in Post-Civil War England

contributor:
Silcox, Mary
English and Cultural Studies

subject: Social theory; intellectual history; social cohesion; political science; metaphysics; space; space-making; history of science; natural philosophy; free will; inequality; social structure; seventeenth-century England; non-fiction prose

abstract:
This dissertation examines how the chaotic social space of post-civil war England inspired new ideas of the ideal social structure and its ability to create social and political stability. Focusing on three non-fiction prose tracts, Margaret Cavendish’s Worlds Olio (1655), Thomas Traherne’s Christian Ethicks (1675), and Gerrard Winstanley’s Law of Freedom (1652), I use the concept of “space-making,” or “how texts aided readers in producing the space in which they understood humanity to be living” (Sauter 47), to engage three distinct perspectives on social cohesion. I situate my study within the larger context of the scientific revolution, and what Michael Sauter calls the “spatial reformation,” whereby humanist thinkers embraced Euclidean geometry to “make” space in a manner akin to God.
I argue that, through their writing, Cavendish, Traherne, and Winstanley structure theoretical space to control, guide, or influence how social beings relate to one another and to the state. In doing so they make social space heterogeneous. The authors create theoretical spaces in which alternatives to England’s social structure are outlined. These alternatives reflect the subjectivity and interests of the space-maker, and while each author wishes to establish social cohesion in post-civil war England, the spaces they create reveal unique perspectives on social responsibility, free will, and self-preservation, leading readers to question the benefits and drawbacks of social cohesion.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)

abstract: This dissertation examines three works of non-fiction prose by Margaret Cavendish, Thomas Traherne, and Gerrard Winstanley, all of whom were seventeenth-century writers. I examine the ways that social structure in post-civil war England in fact rejects the geometric premise popular among canonical natural philosophers that all space (including the spaces we inhabit as human beings) was homogeneous. Instead, I argue that homogeneous space is oppressive in a social context, while also acknowledging that heterogeneous social spaces (spaces that are divided and have distinct "parts") also tended to limit the free will of social actors, particularly those in the lower classes. I examine themes related to free will, self-interest, and subjectivity, specifically with respect to how these themes can both create or detract from social cohesion.


title: MAPPING THE INTELLECTUAL STRUCTURE OF MIDDLE EASTERN STUDIES: AN AUTHOR CO-CITATION ANALYSIS

contributor:
Fox, John
Sociology

abstract:
The focus of my dissertation is on Middle Eastern Studies (MES) as produced in English from the mid-20th century onward. The historians of MES talk about a post-Saidian divide in the field between academic-left and -right. When examining this divide, the common practice has mainly been to focus on how political developments affected MES. This work analytically transcends the political surface and ask whether the two clusters can be observed in the mapping of MES. It then explores the properties of this intellectual map, and asks how, in the overly political field of MES, ‘the social’ and ‘the cognitive’ aspects of knowledge production interact.
To map MES this work uses Author Co-Citation Analysis (based on the relative frequencies with which pairs of authors are cited together by citing documents). The research population comprises 202 influential scholars who have produced knowledge in English about the cotemporary period or recent history of the ME. Google Scholar was used as the source of citation data, and the node attributes, along with the scholars’ political and paradigmatic tendencies, were collected from their online profiles.
The map shows no indication of a polarization in the field but shows differences between insider and outsider inquiries and verifies the local situatedness of the process of knowledge production. The network hints towards the presence of at least three clusters, but not along the lines of the scholars’ political and paradigmatic tendencies. Knowledge about the ME as whole is produced in a cooperative endeavor among scholars with different geographical connections, but in the case of Israel and Turkey, the clusters are more homogeneous. The intellectual map also points towards the silenced voices: those who are strongly associated with Iran and Arab countries and shows how geopolitically hegemonic sites of knowledge production act as barriers against the formation of an in-between discursive space.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract:
The focus of my dissertation is on knowledge production: Middle Eastern Studies (MES) as produced in English from the mid 20th century onward. This dissertation uses the clusters of influential MES scholars to ask whether the there is an academic left-right separation the network and whether the personal backgrounds of scholars’ co-citations (based on the relative frequencies with which pairs of authors are cited together by citing documents) explain the clustering.
The co-citation network hints towards the presence of three clusters, but not along the lines of scholars’ political tendencies. Knowledge about the ME as whole is produced by scholars with different personal and academic backgrounds, but the Turkish and Israeli studies clusters are more homogeneous. Other subfields, such as Iranian or Arab studies, are not large enough to draw any definite conclusion, but scholars with stronger associations to Iran and Arab countries are mostly absent in the network.


title: The Impact of Source-Country Gender Inequality on the Acculturation, Structural Integration and Identification of Immigrants in Canada

contributor:
Kaida, Lisa
Fetner, Tina
Sociology

subject:
Immigration
Integration
Gender Inequality
Canada
Sense of belonging
Sport
Financial decisions

abstract: Many immigrants arrive in Canada from countries with different degrees of gender inequality. While Canada has relatively high levels of gender equality, many immigrant-origin countries are characterized by high levels of inequality between men and women. Studies show that source-country gender inequality negatively impacts immigrant women's socioeconomic outcomes in the host society. However, little is known about how source-country gender inequality impacts social aspects of immigrant adjustment in Canada. This dissertation examines how source-country gender inequality impacts acculturation, structural integration and identification. My analyses of data from the Ethnic Diversity Survey and General Social Surveys find that source-country gender inequality can benefit identification when measured by sense of belonging to Canada. In other cases, it can be a barrier when acculturation is measured by financial decision-making. Further, source-country gender inequality can have little impact on the structural integration of immigrants when measured by sport participation. The results suggest that source-country gender inequality affects immigrant men and women in complex and multifaceted ways.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)


title: Moecular Profiling of Blood for Diagnostics and Discovery

title: AN EXHIBITION OF BLOOD MOLECULAR PROFILING FOR DIAGNOSTICS  AND DISCOVERY

contributor:
Forsythe, Paul
Medical Sciences

subject: PTSD MDD asthma gut-brain probiotics prostate cancer blood omics

abstract: Molecular profiling of blood for several purposes, 1) To identify prostate cancer biomarkers, 2) to identify commonalities between asthma and mood disorders, and 3) to identify mRNAs that may be involved in psychobiotic changes to behaviour.

abstract:
Every cell of the body has the opportunity to secrete molecules into the blood.
These molecules: proteins, RNAs, and DNAs, can be secreted freely, or within
extracellular vesicles (EV). The complement of specific molecules secreted by cells can
vary in accordance with changes to their immediate environment, such as disease in a
particular organ. Cells of the immune system which circulate in the blood may also
change the rates at which they produce these molecules in response to a disease or
unusual event occurring somewhere within the body. The full complement of proteins,
RNAs, or DNAs from all sources within the blood can therefore be measured to garner
information about disease states and communication between every tissue of the body. In
this body of work, we leveraged this to address three separate challenges within medical
science. First, we utilized blood as a source of biomarkers for disease and disease
severity; isolating EVs from the blood of prostate cancer patients and healthy subjects
and characterized their proteins with mass spectrometry to identify potential biomarkers
for prostate cancer and its stages. Next, we explored the ability of blood to identify
commonalities between distinct but often comorbid diseases; here we utilized publicly
available datasets to identify transcripts or gene sets potentially facilitating the
relationship between PTSD, MDD, and asthma. Finally, we utilized differential gene and
gene sets expression to gain mechanistic insight into microbiota-gut-brain axis;
investigating the hippocampus and blood of mice fed one of two psychobiotic bacteria:
Lactobacillus rhamnosus JB1, Lactobacillus reuteri 6475. The analysis identified several
mRNA expression differences potentially responsible for the mood-altering characteristics of these psychobiotic bacteria. This body of work illustrates the utility of
blood omics data for addressing many problems within medical science, and highlights
the large scale of information stored within the blood.

abstract: Thesis

abstract: Doctor of Philosophy (Medical Science)

abstract:
Every cell of the body has the opportunity to secrete molecules into the blood.
These molecules: proteins, ribonucleic acids (RNAs), and deoxyribonucleic acids
(DNAs), can be secreted freely, or within small membrane compartments called
extracellular vesicles (EV). Specific molecules are secreted more or less by cells
depending on changes to their immediate environment, such as disease in a particular
organ. We leveraged this to the benefit of medical science in three separate scenarios: 1)
using the molecular contents of EVs to determine when someone has prostate cancer, and
at what stage; 2) examining RNAs of the blood to determine why so many with asthma
also have depression or PTSD; 3) measuring RNAs in the blood and hippocampus of
mice to better understand how certain bacteria in the gut can alleviate depression. This
work illustrates the utility of blood in tackling many challenging problems within medical
science.


title: Supporting the Development of Trustworthy Essential Medicine Lists and their Synergy with Health Guidelines

contributor:
Schünemann, Holger
Health Research Methodology

subject:
Essential Medicines
Health Evidence
Guidelines
GRADE

abstract: Essential Medicine Lists (EMLs) are important for the prioritization and availability of medicines around the world. Since the first Model List of Essential Medicines (MLEM) from the World Health Organization in 1977, the list has expanded from 208 to 479 medicines. The availability of essential medicines is a key priority under the World Health Organization’s Universal Health Coverage agenda & the United Nation’s Sustainable Development Goals (in particular goal 3.8 Coverage of Essential Health Services). EMLs are an important tool to inform health decisions at a country-level and at least 137 countries now have their own national EML. Despite this, there is wide variability in the methods used to develop them, and the certainty of evidence of medicines included on WHO’s MLEM and national EMLs. Additionally, a lack of coordination may result in time delays in updating EMLs or unnecessary duplication of efforts between EMLs and other evidence synthesis and health decision-making paradigms, such as health guidelines. In this thesis, we seek to understand the decision-making process for EMLs with particular focus on WHO’s MLEM, and to identify and advance opportunities to coordinate their development with health guidelines. This is accomplished through three papers, which build upon each other in this sandwich thesis. Paper 1 is a qualitative interview study with EML and guideline stakeholders to better understand decision-criteria and processes in EMLs. Paper 2 evaluates, using user-experience testing, a framework for the connection of guidelines and EMLs using an Evidence-to-Decision (EtD) framework for EMLs. Paper 3 presents a stakeholder-driven Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group concept paper exploring the conceptual challenges and opportunities of linking guidelines and EMLs using case studies on real-world implementation of this connection.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: Medicines are important for treating health conditions, and the most important medicines are called essential medicines. Essential Medicine Lists (EMLs) are created to determine what should be considered an essential medicine around the world, and also to ensure people have access to them. The number of medicines on the World Health Organization’s Model List of Essential Medicines (MLEM) has grown since it was first released, but these medicines aren’t always available to treat people who need them. Sometimes medicines that are not the most important are included on national essential medicine lists. The way that the WHO EML and national EMLs are made has been under review and criticized. Health guidelines tell people how medicines should be used, however, the connection between EMLs and health guidelines is not always consistent. Sometimes they may say different things about the same medicine. Additionally, there are differences in how EMLs and guidelines are established, and those involved do not always work with each other. In this thesis, I try to understand how decisions about which medicines are included in EMLs are made, and how they connect to health guidelines. Chapter 1 is an introduction to the topic. Chapter 2 asks experts about the decision-making process for EMLs. In chapter 3, we change a tool for guidelines to help connect guideline and EML decisions and ask for feedback regarding improvements. Chapter 4 presents the work with a group of guideline experts to present problems and suggest ways to overcome them to make EMLs and health guidelines better connected.


title: A Systematic Approach to Critical Electrical Fault Mitigation Strategies in an Electric Vertical Take-Off and Landing (EVTOL) Electrical Propulsion Unit

contributor:
Emadi, Ali
Electrical and Computer Engineering

subject:
EVTOL
Electrical propulsion unit
Fault Protection
Electrical fault
Solid State Power Controller

abstract:
The electric vertical take-off and landing (EVTOL) platform is opening a new market segment that is disrupting the commercial and military aircraft industry. This particular vehicle platform is filling the gap between road vehicles and aircrafts. The main idea is to avoid the gridlock in major metropolitan cities where a journey that should take 30 minutes now takes more than one hour. Key enablers such as the newly developed infrastructures known as Vertiports and the move of electrification of aircrafts have driven this new market segment with fast time to market. To enable the deployment of these EVTOLs in the commercial world, their fault behavior needs to be known as faults will happen, a fault mitigation strategy must be developed to ensure that when the fault happens, the EVTOL and its passengers along with its surrounding are protected from catastrophic failures.

To give a brief context on what these EVTOL platforms are, potential and developed EVTOLs in the market currently are introduced. The categorization of these platforms is done within four types of categories being Helicopters, Multi-Rotor, Lift & Thrust and Tilt-X. Their general advantages and disadvantages are discussed and the categories are rated in terms of which platform could be the most viable option to be in service by 2024. Their main electrical distribution system is introduced with their critical components and how they can fail. Each critical component such as the battery, electrical propulsion unit (EPU), protection devices, power distribution units and auxiliary electrical loads are discussed in details.

The thesis discusses one of the main safety aspects of an EVTOL, which is protection of a propulsion unit. The critical electrical faults in the EPU are introduced along with their behavior on the EVTOL electrical distribution system (EDS). Open circuit faults and short circuit faults from the inverter and its power devices to the electric motor are analyzed. Furthermore, the sensor failures such as the rotor position sensor and the current and voltage sensors are discussed. The controller stage failures are discussed as well as it becomes a critical component that can fail in many ways.

Once the electrical faults are discussed, a fault mitigation strategy (FMS) is introduced for each fault ranging from a simple inverter disabling strategy, to a sensorless control law for the loss of position sensor. A protection device known as the solid state power controller (SSPC) is inserted at the input of the EPU and its design is discussed for a 270VDC/180A modular architecture. This SSPC becomes the redundant and final protection stage of the EPU to ensure if the developed FMS fail to protect the EPU, the SSPC can isolate the EPU from the rest of the EVTOL EDS. The main contribution of the thesis is the systematic approach to fault analysis and mitigation/protection strategies that were not addressed in literature so far for this type of platform. The use of a single FMS for multiple faults is introduced where the aim is to reduce the efforts for verification and validation (V&V) of the corresponding software and firmware. Finally, the practical implementation challenges of the SSPC are discussed and shown in experimental lab setups.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)


title: Stand-off Nuclear Reactor Monitoring with Neutron Detectors at the McMaster Nuclear Reactor

contributor:
Buijs, Adriaan
Engineering

subject:
Nuclear Safeguards
Nuclear Engineering

abstract:
Nuclear reactor safeguards are how the peaceful use of nuclear material is ensured.
Safeguards consist of a broad array of techniques, such as video surveillance and tamperproof
seals, to ensure that nuclear material is not diverted from declared activities.
Safeguards research is conducted to ensure that safeguards techniques are capable of
meeting the challenges posed by future reactor designs and operating conditions. One
such technique that has broad applicability to novel reactor designs, including small
modular reactors, is the method of standoff neutron detection using large area neutron
detectors. In this method, neutron detectors are employed to detect neutrons which
have escaped from the core, which are representative of the flux inside the core. Because
the flux required to achieve a given power is dependent on the isotopes being fissioned,
due to their different cross sections and fission energies, the state of the core can be
assessed using the neutron detectors. Prior research has demonstrated that it is possible
to correlate kilogram changes in fissile inventory using neutron detectors by employing
the standoff neutron detector method. This work at the McMaster nuclear reactor details
additional experiments to support prior work.
First, the apparatus and procedure to collect neutron detector data are detailed, along
with persistent challenges to the collection. Next, simulations using the OSCAR-5 code
to determine the fissile inventory are described. These two sections are subsequently
combined, to compare changes in detector signal to the simulated core inventory. It
was found that the uncertainty was too large to correlate changes in detector signal with
changes in core inventory. Lastly, a method of detecting malicious interference is derived
and tested.

abstract: Thesis

abstract: Master of Applied Science (MASc)


title: Mechanism investigation of synthesizing carbon quantum dots from coal by numerical simulation

contributor:
Xu, Gu
Materials Science and Engineering

abstract: As fluorescent nanomaterial with excellent properties, carbon quantum dots have attracted significant attention. In particular, the synthesizing of carbon quantum dots has become the focus of various studies. Among them, carbon quantum dots synthesized from coal by strong acid oxidation have been widely studied for mass production. However, the broad size distribution of the products restricts their development, thereby prompting an issue that needs to be urgently resolved. Therefore, in this study, to achieve the control of size distribution, we simulated the diffusion process, in which sulfuric acid is inserted into the graphene layers of coal and destroys the van der Waals bonds. The result showed that when graphene layers are longer than 5 nm, the van der Waals bonds between them could not be broken within 10000 iterations. For bituminous carbon quantum dots, since its crystal structure size is small, the van der Waals bonds can be effectively broken, and narrow size distribution can be obtained at the 1500th iteration, which corresponds to the actual time of 34.2 h; for coke carbon quantum dots, since the crystal structure average size is larger than 5 nm, diffusion process cannot effectively break van der Waals bonds. The simulated result unravels the mechanism, guiding the experimental method to obtain a narrow size distribution and avoiding blind trials.

abstract: Thesis

abstract: Master of Materials Science and Engineering (MMatSE)


title: God and Humanity in John Milton's Paradise Lost

subject:
God
humanity
Paradise Lost
identity
relationship
interpersonal

abstract: This thesis concerns questions of being in good relation, with others and the created world, in John Milton’s Paradise Lost, which shows interdependent and positive self-other relationships in Eden, as well as a mutual, constructive, and enduring relationship between God and humanity. Working with Lee Morrissey’s suggestion that “subjectivity requires difference, not, as Adam had assumed, similarity” (“Eve’s Otherness” 340), my thesis not only suggests that Milton’s poem esteems relationships that recognize others as welcome additions to the self – hence, Milton’s “other self” (8.450, 10.128) – rather than subtractions or even self-absorptions, but also explores what specific differences emerge across relationships (e.g., God the Father, God the Son, and God the Holy Spirit versus Satan, Sin, and Death) and how they might fulfill or, conversely, upend God’s plan for His original created good to continue as such. I argue that within Paradise Lost, both earthly and divine self-identity develops and becomes fully realized only through relationships with others. And further, because the good in the created world of Paradise Lost comes from humanity’s relationship with God, this relationship is the basis of all relationships that are good.

abstract: Dissertation

abstract: Doctor of Philosophy (PhD)

abstract: This dissertation studies relationships in John Milton’s Paradise Lost, a poem that shows interdependent and positive self-relationships in Eden, as well as a mutual, beneficial, and enduring relationship between God and humanity. My thesis not only suggests that Milton’s poem extols relationships that recognize others as welcome additions to the self rather than subtractions or even self-absorptions, but also explores what specific differences emerge across relationships (e.g., God the Father, God the Son, and God the Holy Spirit versus Satan, Sin, and Death) and how they might help or impede God’s plan for His original created good to continue for all time. I argue that within Paradise Lost, both earthly and divine self-identity develops and becomes fully realized only through relationships with others. Further, because the good in the created world of Paradise Lost comes from humanity’s relationship with God, this relationship is the basis of all relationships that are good.


title: Solid-State and Diffusional Nuclear Magnetic Resonance Investigations of Oxidatively Stable Materials  for Sodium Batteries

title: Development of Oxidatively Stable Battery Materials

subject:
solid state nuclear magnetic resonance
sodium oxygen battery
lithium ion battery
sodium ion battery
energy storage

abstract:
This thesis focuses on the development of oxidatively stable cathode and electrolyte materials for sodium-based battery systems. This is primarily achieved through the use of solid-state nuclear magnetic resonance (ssNMR) and pulsed-field gradient (PFG) NMR spectroscopy.
ssNMR is used to diagnose the primarily failure mode of the NaOB. It is found through a combined 23Na and 19F study that the main discharge product of the cell, NaO2, oxidizes both the carbon and polyvinylidene fluoride (PVDF) binder of the cathode to produce parasitic Na2CO3 and NaF. In a subsequent study, Ti4O7-coated carbon paper cathodes are implemented in an attempt to stabilize NaO2. The 23Na triple quantum magic angle spinning (3QMAS) and 1H to 23Na dipolar heteronuclear multiple quantum correlation (23Na{1H} D-HMQC) experiments are used to diagnose the failure modes of carbon-coated, and Ti4O7-coated cathodes. It is found that electrochemically formed NaO2 is significantly more stable in Ti4O7-coated cathodes, leading to longer lifetime NaOBs.
Oxidatively stable electrolyte materials are also examined. Lithium and sodium bis(trifluoromethansulfonyl)imide (TFSI) in adiponitrile (ADN) electrolytes exhibit extreme oxidative resistance, but are unusable in modern cells due to Al corrosion by TFSI, and spontaneous ADN degradation by Li and Na metal. PFG NMR is used to investigate the transport properties of LiTFSI in ADN as a function of LiTFSI concentration. By measuring the diffusion coefficient of Li+ and TFSI as a function of diffusion time (Δ), diffusional behaviour is encoded as a function of length scale to study the short- and long-range solution structure of the electrolyte. It is found that at high concentrations, LiTFSI in ADN transports Li+ primarily through an ion-hopping mechanism, in contrast to the typical vehicular mechanism observed at low concentrations. This suggests significant structural changes in solution at high concentrations.
The NaTFSI in ADN analogue is examined for its electrochemical properties in Na-ion and Na-O2 batteries. It is found that the oxidative resistance of ADN to Na metal is significantly increased at high concentrations, leading to reversible Na deposition and dissolution in cyclic voltammetry (CV) experiments. Linear sweep voltammetry (LSV) and chronoamperometry (CA) experiments on Al current collectors show that Al corrosion by TFSI is similarly suppressed at high concentration. This culminates in high concentration NaTFSI in ADN being able to reversibly intercalate Na3V2(PO4)2F3 (NVPF) cathodes in SIB half-cells for multiple cycles.
The knowledge gained from exploring oxidatively stable cathode and electrolyte materials can be used in tandem for the development of a longer lifetime, more oxidatively stable, NaOB in the future.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract:
The continued development of rechargeable batteries is paramount in reducing the world’s reliance on fossil fuels, as they allow for the storage of electrical energy produced by renewable sources. This work primarily examines sodium-based batteries systems, such as the sodium-oxygen battery (NaOB) and sodium-ion battery (SIB), which are possible alternatives to the currently used lithium-ion battery (LIB) system.
In order to produce energy, NaOBs produce sodium superoxide (NaO2) during the discharge process, which is formed on the carbon cathode. However, NaO2 is inherently unstable to carbon materials, causing degradation of the battery overtime. Ti4O7 is investigated as a stable coating material in NaOBs, used to coat the carbon cathode to make the system more stable to NaO2 degradation. The degradation processes in NaOBs are characterized by solid state nuclear magnetic resonance (ssNMR) spectroscopy, which uses strong superconducting magnets to probe the magnetic properties of, and consequently identify, the chemical species formed within the battery. It is found that the addition of the Ti4O7 coating inhibits NaO2 degradation, producing longer lifetime NaOBs.
 Subsequently, both Li-bis(trifluoromethansulfonyl)imide (LiTFSI), and NaTFSI, in adiponitrile (ADN) electrolytes are examined for their use in LIBs and SIBs, respectively. Electrolytes facilitate stable ion transport within the cell, and ADN electrolytes specifically allow for the use of higher voltage cathode materials, which can result in a higher energy density battery. The transport properties of LiTFSI in ADN electrolytes are studied by a pulsed-field gradient (PFG) NMR technique, that allows for the measurement of the rate of ion transport in the electrolyte. It is found that the mechanism of ion transport significantly depends on electrolyte concentration, which suggests significant changes to the electrolyte solution structure at high concentration.
The electrochemical ramifications of this are studied for the NaTFSI in ADN electrolyte in SIBs. It is found that the electrolyte becomes substantially more stable at high concentrations, leading to more favourable charging and discharging behaviours when tested in SIBs.
The work presented in this thesis illustrates the development of more stable, longer lifetime, batteries over a number of cell chemistries, using a variety of NMR and electrochemical characterization techniques.


title: Three Papers on Retirement and Canada's Public Pension System

contributor:
Sweetman, Arthur
Economics

subject:
Retirement; public pension
Administrative data

abstract: In three chapters, I focus on how, and which, policy parameters of Canada’s public pension system affect seniors’ labour supply decisions. First, I study seniors’ labour supply responses to a series of reforms in 2012 and 2013 that incentivized many pensioners to extend their working lives; second, I assess how and whether receipt of public pension benefits affects seniors’ retirement timing differentially for those with different past earnings at ages 50-53; and, finally, I investigate older immigrants’ retirement and pension claiming decisions and how these decisions are impacted by permanent residency requirements for benefit eligibility. My analyses were carried out using income-tax and related panel data from the Longitudinal Administrative Databank (LAD), a 20% sample of taxpayers spanning the years 1982-2019 at the time of writing. In addition to detailed income-tax information, it contains information on receipt of non-taxable transfer income.

abstract: Dissertation

abstract: Candidate in Philosophy


title: COGNITIVE OFFLOADING AND NOTE-TAKING: IDENTIFYING THE GAPS BETWEEN APPLIED RESEARCH AND INCLUSIVE LEARNING DESIGN

contributor:
Monteiro, Sandra
Psychology

subject:
Cognitive offloading
Note-taking
Individual differences
Saving-enhanced learning
Lecture parameters
Test parameters
Working memory capacity
Note-taking habits
Inclusive design
Applied cognition in education

abstract: Note-taking is ubiquitous. Whether we write down a grocery list, type our intentions for the day, or record a voice note for a friend, we often use notes to externalize our thoughts. We “delegate” this information to “in the world” extensions of our cognition, thus lightening our cognitive loads. The current thesis investigates the effects of note-taking as a form of cognitive offloading in an applied research setting. The note-taking literature is fragmented regarding practical note-taking recommendations for educators. The current thesis advances our knowledge and understanding of the crossover between cognitive offloading, note-taking, and individual differences. The laboratory research presented in this thesis uses novel materials that mimic the classroom environment, with future goals of translating this research into the actual classroom. Chapter 2 explores note-taking from a cognitive offloading perspective and demonstrates how differences in note-taking quantity affect recall. Chapter 3 showcases how differences in learning between note-taking modalities are seen sporadically and only when they intersect with the type of test. Chapter 4 investigates the importance of individual differences (e.g., working memory capacity) when exploring cognitive offloading and note-taking, and demonstrates how surface findings are not generalizable once we investigate underlying individual differences. While our research started as a way to understand how we offload information via note-taking and its effects on learning, we hope our findings and general discussion encourage the reader to explore the generalizability of applied cognitive research. Note-taking is a complex process, and our future work aims to investigate how learners differ and how we might disseminate research in education to be inclusive and diverse.

abstract: Thesis

abstract: Doctor of Philosophy (PhD)

abstract: Imagine a world without technology or external resources to express your thoughts: no “to-do” lists, calendar reminders, sketches, or notes. Since our memory capacities are limited, we often maintain a record of information “in the world”, as opposed to only using our limited memory stores. This form of mental delegation is known as “cognitive offloading”. One way we offload information for future access is through note-taking. In an educational setting, note-taking influences our ability to learn and review information. How we take notes, and their effects on learning, have been debated in the literature. This thesis explores the impact of cognitive offloading and note-taking on learning, and demonstrates the importance of exploring individual differences (e.g., memory capacity and note-taking preference) in applied educational research. Throughout this thesis, we prompt our audience to frame note-taking and cognitive research takeaways through an inclusive educational lens.


title: Elizabeth I in Contemporary Historical Fiction: Gender and Agency in Four Novels

subject:
historical fiction
Elizabeth Tudor
Elizabeth I

abstract: In this thesis, I analyse four historical fiction novels as recharacterizations of Elizabeth I’s agency, to argue for the merit of fictionalized narratives of history. These narratives address the conflict between Elizabeth’s political and natural bodies, which I investigate in view of Ernst Kantorowicz’s concept of kingship, while emphasizing her learned experience and perseverance as responsible for her success. In doing so, historical fiction novels represent the motivations of the contemporary author and reader while also asserting the agency and capability of female rulers like Elizabeth, retroactively. In her own time, Elizabeth’s female body was a point of contention in patriarchal England, and early modern authors highlighted her chastity to represent the queen as beyond the rest of humanity, particularly women. In this thesis, I assess how contemporary authors respond to such history, to represent Elizabeth as a fallible woman in a novel way. Elizabeth’s fallibility in these texts represents the capabilities of women in power, credited to their female experience rather than the supernatural status or divine appointment of the early modern ruler. While there is a breadth of research available pertaining to historical depictions of Elizabeth, fewer critics focus upon contemporary accounts. Elizabeth’s legacy in film is represented in such research, but few critics have analysed her presence in historical fiction, though she is a popular heroine of the genre. This thesis examines the prioritization of Elizabeth’s female body in her youth in Robin Maxwell’s Virgin: Prelude to the Throne (2001), her experiences as an unwed queen in Alison Weir’s The Marriage Game (2014) and Susan Kay’s Legacy (1985), and her role as a mother figure in Anne Clinard-Barnhill’s Queen Elizabeth’s Daughter (2014). These authors assert Elizabeth’s agency and demonstrate the value of historical fiction as a genre, rewriting history to reflect female experience as an asset.

abstract: Thesis

abstract: Master of Arts (MA)

abstract: In the sixteenth and seventeenth centuries, authors depicted Elizabeth I as an extraordinary ruler appointed by God and an extraordinarily chaste woman. Such authors acknowledge Elizabeth’s flawed, natural body, as mortal and female, but praise her incomparable chastity as surpassing other women and ensuring a strong political body or government. While contemporary fiction authors also assess a separation between the political and private, they prioritize individual interiority and female capability as they construct Elizabeth’s navigation of a patriarchal court as a woman in power. This thesis investigates historical fiction, in four novels, as a valuable space for authors to rewrite the agency of Elizabeth I through narratives in which she demonstrates her own decision making and emotional complexity. In this thesis, I assess agency in Robin Maxwell’s Virgin: Prelude to the Throne (2001), Alison Weir’s The Marriage Game (2014), Susan Kay’s Legacy, and Anne Clinard Barnhill’s Queen Elizabeth’s Daughter (2014).