VictorJuiz/thesis huggingface dataset:
Swallowing Physiology and Impairment in Individuals with Amyotrophic Lateral Sclerosis (ALS)

Dysphagia, or swallowing impairment, is a common symptom of bulbar disease in Amyotrophic Lateral Sclerosis (ALS). Dysphagia in ALS significantly affects quality of life and places an affected individual at risk of developing chest infections, becoming malnourished, and shortened life expectancy. The purpose of this doctoral thesis is to provide a comprehensive overview of swallowing physiology in ALS and elucidate potential relationships between swallowing physiology and clinical swallowing function. The first chapter of this thesis provides an introductory overview of normal swallowing, dysphagia, and ALS pathology, highlighting commonly reported swallowing impairments and associated complications in individuals with ALS. Chapter 2 builds on this discussion through a comprehensive review of research literature on dysphagia in ALS. Following scoping review methodology, we identified research trends and areas for further exploration, including a need for further quantitative analysis of swallowing physiology. Chapter 3 involves a retrospective, cross-sectional study of swallowing physiology in ALS, using quantitative videofluoroscopic analysis. Measures of pharyngeal area at maximum constriction and swallow-related hyoid kinematics were obtained and compared against reference data to test face validity of the measures and identify changes associated with disease pathology. Through this analysis, we identified reductions in maximum pharyngeal constriction and anterior hyoid movement, compared to healthy reference data. Further, we revealed relationships between enlarged maximum pharyngeal constriction areas and measures of swallowing inefficiency. Expanding on these findings, we completed a comprehensive summary of swallowing physiology and function in ALS, summarized in Chapter 4, comparing additional metrics of swallowing physiology against healthy norms, examining relationships between parameters of swallowing physiology and function (i.e., safety/efficiency), and exploring modulatory effects of liquid thickness. Proposed approaches to future research, incorporating theories of motor control and methodological frameworks, are provided in Chapter 5.

Keywords: dysphagia
swallowing
videofluoroscopy
Advisor: Steele, Catriona M
Extending the Breadth of Metal Halide Perovskite Applications to the Control and Modulation of Light

The rapid rise of metal halide perovskites as photovoltaic materials has been an impressive achievement. Their performance as solar energy harvesters stands out amongst solution processed materials. Metal halide perovskites have also emerged as efficient light emitters for potential use in light emitting diodes and lasers. Their promise derives from a combination of their solution processing, desirable optical and electronic properties, and compositional flexibility. Perovskites can be engineered to have sharp absorption onsets, high photoluminescence quantum yields, and low trap state densities. In this thesis I present applications of metal halide perovskites in the control and modulation of light. I expand their applicability by exploiting nonlinear and electro-optic processes in these materials. I begin by investigating the electro-optic behaviour of germanium halide perovskites. The electro-optic coefficients of these compounds are calculated using density functional theory. CsGeI3 is predicted to have an electro-optic coefficient of 47 pm·V-1 at the communications wavelength of 1550 nm, exceeding the greatest coefficient of lithium niobate. This study is the first exploration of the linear electro-optic process in metal halide perovskites. Next, I study quantum-confined Stark effects in layered perovskites. Electroabsorption spectroscopy is conducted with thin films of two-dimensional metal halide perovskites featuring either methylammonium or cesium cations bound in the quantum well structures. While the cesium compounds display conventional energetic red-shifts, methylammonium compounds exhibit blue-shifts. These anomalous blue-shifts are attributed to extraordinary weakening of the exciton binding energy ultimately induced by polarization of the methylammonium dipoles. Both the red-shifts and blue-shifts are engineered to produce modulations in the amplitude of the absorption coefficient of 70 cm-1 for 56 kV·cm-1 applied fields, the strongest modulation amplitudes reported for solution processed materials at room temperature. Lastly, I characterize two-photon absorption in methylammonium lead bromide perovskite crystals. I determine the nonlinear absorption coefficient, along with its polarization dependence. A two-photon absorbing photoconductor was fabricated to autocorrelate ultrafast laser pulses and demonstrate the applicability of this process in metal halide perovskites.

Keywords: Electro-optics
Hybrid
Nanomaterials
Nonlinear Optics
Perovskites
Photonics
Advisor: Sargent, Edward H
Expertise in the Age of Digital Fabrication

This dissertation investigates the history, development, and practical application of digital fabrication. I leverage past and current scholarship from the fields of information, science and technology studies, and the history of computing in order to examine the themes of automation, control, and expertise. As current developments in artificial intelligence demonstrate, emerging computational technologies continue to re-configure normative roles and relationships in society. Previous studies of computation and labour have demonstrated that certain kinds of abstract expertise or knowledge are privileged by these changes. Understanding how and why certain kinds of abstract expertise and knowledge were privileged in the past, and how this informs current versions of these systems, is therefore critically important given the current rhetoric around automation and the future of work. My research seeks to actively re-engage the role human actors play in the technological mediation of labour, addressing the epistemic hierarchies produced by digital design and manufacturing technologies. I accomplish this by combining historical analysis of archival resources and ethnographic fieldwork to examine the origins of numerical control (N/C) and computer-aided design (CAD) in manufacturing and their shift into new professional contexts, specifically the field of prosthetics and orthotics (P). I chose P because the labour and expertise utilized by the profession is separate from the epistemic considerations of digital fabrication. As such, specific sets of knowledge practices within the field of P do not translate cleanly to computational outcomes. Yet, I found that professionals within this context were willing to adopt these technologies as it allows for their expertise and labour to be expressed to those outside the profession. Within the context of information studies, this dissertation provides the historical and evidentiary ground work necessary for understanding and addressing the processes behind why certain kinds of labour, expertise, and knowledge become configured as appropriate for humans.

Keywords: Automation
Digital Fabricaiton
Expertise
History of Computing
Labour
Prosthetics and Orthotics
Advisor: Ratto, Matt
Wireless Sensors using Radio-frequency Identification Technology: Developing Carbon Nanocomposites for Improved Sensing and Detection of Ammonia Gas and Volatile Amine Vapors

Nowadays, the emergence of Radio-Frequency Identification (RFID) devices at costs comparable to barcodes are providing an incredible opportunity for designing interconnected networks of “things” that allow for the wireless identification of products and monitoring of the chemical composition of the surrounding environment. This has major implications for the chemical and food sectors, for which the design of interconnected networks with sensing capabilities has many practical applications. My thesis focuses on exploiting the advantageous characteristics of novel carbon nanomaterials, carbon nanotubes and graphene to design conductive nanocomposites with improved sensing capabilities for ammonia gas and amine vapours. For this purpose, we developed two types of conductive nanocomposites; one that consisted of carbon nanomaterials, maleic anhydride and electrically insulating polyethylene-co-vinyl acetate polymer matrix; and the other that consisted of carbon nanomaterials and an intrinsically conductive polymer, polyaniline. For the first type of nanocomposite system, we demonstrated that grafting the maleic anhydride on the carbon nanotubes significantly improved the sensitivity of the nanocomposites toward amines. It was postulated that these improvements were the result of the binding of putrescine between the carbon nanotubes, which facilitated a more effective disruption of the conductive network. For the second type of nanocomposite, we demonstrated that conferring n-type semiconductive behavior to the graphene nanosheets, via nitrogen or phosphorus doping, improved the sensitivity of graphene/polyaniline nanocomposite by a factor 2 and 5, respectively, to reach a detection limit in the sub-ppm range toward ammonia gas. The enhancement was due to the formation of localized p-n heterojunctions in the nanocomposites and the modification of the semiconductive behavior of the nanocomposite during exposure to ammonia. Furthermore, we tested the novel polyaniline/phosphorus doped graphene nanocomposite sensing elements on RFID split-ring resonators and showed that the wireless sensor had excellent detection capabilities toward ammonia gas down to the sub-ppm range of concentration. Based on the sensing performance achieved, this thesis demonstrates the potential of RFID technology as a platform for the design of wireless sensor networks with high detection capabilities, and are thus practically applicable in the chemical, medical and food sectors, among others.

Keywords: Ammonia
Chemical sensors
Doping
Graphene
Polyaniline
Advisor: Yan, Ning
A Living History (1973-1993): How the Experiences of Early Activists Shaped the Violence Against Women (VAW) Movement in Ontario: A Case Study

This dissertation shines a light on a group of women who helped to create a violence against women (VAW) movement that changed the course of history in Ontario, Canada for countless women, their families and their communities. This study centres the voices of activists, positioning them as knowledge producers with expertise and wisdom gleaned during five decades of work in the VAW movement in Ontario. A feminist analysis of the VAW movement begins from the standpoint of women. In particular, an intersectional feminist analysis begins from the standpoint of diverse women who embrace the tenets of critical feminist standpoint theory. This study draws on social movement theory (SMT) literature, particularly the scholarship of feminist SMT researchers, to examine the state of the VAW movement in Ontario, Canada. This dissertation is a story about a social movement, specifically the VAW movement in Ontario—a strand of the women’s liberation movement frequently referred to as the second wave, but also on the cusp of ushering in third wave feminism. I document the time period from 1973 to 1993—a period that spans the start of the era when all of the participants in this study began their activist work—until the time of their interviews, which took place between 2014 to 2018. In this dissertation, I challenge the notion that the VAW movement has been reduced to a VAW sector, merely creating and delivering services to select populations of women. This interpretation suggests that there is a loss or erosion of an expressed political commitment to uncovering and eliminating the root causes of VAW. Using a case study methodology, I argue that the VAW activists in this study have been persistently engaged in and committed to ending VAW, although their activism shifts and manifests in several forms throughout the life cycle of the movement. The findings of this dissertation research are intended to bring practical and useful implications that can enhance future strategies for change in the VAW movement, contribute to the knowledge base of social work, and infuse the VAW movement with renewed energy and critical vision.

Keywords: case study
critical feminist theory
domestic violence
feminism
social movements
violence against women
Advisor: Aleggia, Ramona
Implementing Dialectical Behaviour Therapy: An Exploratory Study of Fidelity and the Fidelity-adaptation Relationship

Objective: The aim of this study was to improve conceptual clarity of implementation fidelity, the degree to which a program adheres to the original program protocol, and the relationship between fidelity and adaptation of a complex health intervention, Dialectical Behavior Therapy (DBT). Methods: Employing a mixed-methods approach, this study utilized secondary DBT client outcome data collected over a one-year period and semi-structured interviews with DBT therapists (program implementers). The study design was informed by the Conceptual Framework for Implementation Fidelity (CFIF) (Carroll et. al, 2007). This framework was adapted to include three categories of factors: individual client (needs, trajectories), programmatic/organizational and program implementer perspectives. Results: Findings suggest that reconceptualization of fidelity and the fidelity-adaptation relationship may require integrating stakeholder knowledge of organizational constraints, experience and values of front-line staff and heterogeneous client trajectories to allow for a more realistically flexible model that is contextually and situationally sensitive. Conclusions: Expanding the CFIF framework offered new insights regarding factors that have the potential to affect the fidelity-adaptation relationship.

Keywords: Complex health interventions
Dialectical Behaviour Therapy
Implementation science
Mental health
Program evaluation
Program outcomes
Advisor: Sridharan, Sanjeev
Essays on Capital Structure and Firm Investment

In this thesis, I study the interactions between firms' capital structure and real decisions. First, I investigate how a firm's financial leverage will impact its investment contingent on whether future growth opportunities are anticipated. Second, I test the under and over investment hypothesis related to debt financing contingent on whether the firm is likely to under or over invest. Last, I investigate how a firm's production technology can impact its production and capital structure decisions. In Chapter 1, I investigate the impact of anticipations of future growth opportunities on leverage-investment interactions. I show that when growth opportunities are unanticipated, the negative impact of leverage on investment is up to two times larger than when they are anticipated. The presence of institutional stockholdings significantly reduces the under investment problem. An instrumental variable analysis reveals that the leverage-investment relationship is weak when the problem of endogeneity is controlled. The results provide strong evidence that Canadian firms take ex ante leverage adjustments to mitigate the debt overhang problem. Chapter 2 studies the extent to which leverage-investment interactions depend on the level of initial investment as well future investment opportunities in US firms. I find a strong negative relationship between leverage and investment for firms with low levels of (initial) investment and high investment opportunities. I also find a positive relationship between leverage and investment for firms with high levels of (initial) investment and low growth opportunities. I distinguish between Tobin's Average Q and Marginal Q as proxies for firms' investment opportunities and propose a novel method to estimate Marginal Q. Chapter 3 is a joint work with Varouj Aivazian. In this chapter, we investigate the interactions between the flexibility of a firm's production and its financial structure. This chapter shows that production flexibility is an important factor explaining the cross sectional variations in financial leverage among U.S. firms. Alternative empirical measures of production flexibility are all shown to be positively associated with financial leverage. This chapter also develops a novel measure of inter-temporal production flexibility and identifies important linkages between production and financing decisions.

Keywords: Capital structure
Debt overhang
Investment
Production flexibility
Advisor: Aivazian, Varouj A.
Cziraki, Peter
Invitation to Ethno-Kinesiology

Many studies today have not considered the foundation of our meta-methods, which are predominantly linguistic and thus descriptive. Any academic understanding we are pursuing is linguistically and descriptively preformed, and this preformation in turn usually precedes academic inquiry. Instead of adapting appropriate methods for the research designed, this study seeks to know what can be objectivized as the object, and how. Using a video camera, and making an ethnographic film, from three different case studies internationally, this study attempts to cultivate a different academic realm that has been missing and can complement existing studies’ unawareness and imbalances, particularly the studies of physical culture and movements. This dissertation argues for method driven inquiry, to let method capture, engage, and correspond with the research. How can we find what can be the object of academic inquiry, and how can we find the question to be pursued? As a result of the process of filmmaking and participation in the practice of judo, this research argues to move from thick to ‘thin description’, present-congruency, and a meta-methodology of subtraction. A new academic realm, ‘Ethno-Kinesiology’ is proposed as a novel way to engage in the research of movement. Keywords: techniques of the body, film ethnography, methodology, physical culture, Henri Bergson, thin description

Keywords: film ethnography
Henri Bergson
physical culture
techniques of the body
thin description
Advisor: Kidd, Bruce
Efficient and High-fidelity Finite Element Models for Fibre Composites

Fibre reinforced composites are widely used as structural components in the aerospace industry. The fabrication of highly tailored fibre composite structures is enabled by advanced composite manufacturing methods, such as Automated Fibre Placement (AFP). AFP enables fibre tows to be placed at arbitrary fibre orientations, either straight or curved, and the local tailoring of composite properties significantly improves the mechanical performance. The conventional finite element approaches assume that the curved fibres are locally straight, and many small elements are needed to model the curved fibres accurately. This increases the computational expense of gradient-based fibre angle optimization as it requires repeated evaluations of the finite element model of the composite. Therefore, the goal of this research is to establish an accurate finite element (FE) model with good computational efficiency for composite structures with complex fibre configurations to be used for gradient-based optimization. In this work, a novel finite element approach that enables the use of larger elements with the desired level of accuracy is formulated for a single-layer thin composite lamina with curved fibres. Fewer elements make the FE analysis more efficient as the dimension of the global stiffness matrices is reduced. The element model represents the real physical system more accurately, as the Gauss quadrature process is modified to capture the stiffness change caused by the fibre curvature in the calculation of element stiffness matrices. As a function of the orientation of fibres in adjacent elements, fibre curvature is calculated by minimizing the fibre discontinuity between adjacent elements given their average fibre orientation. This is a least square minimization problem and solved through its normal equation. Finally, stiffness maximization for the single-layer thin composite lamina is performed using a gradient descent algorithm integrated with the finite element formulation with explicit fibre curvature. The fibre curvature is an intermediate variable to the objective function, and the total derivative of the objective function with respect to fibre orientation is calculated analytically using the adjoint method. The optimal solutions show that this new method gives the same results as optimization using conventional finite elements, but has much faster convergence.

Keywords: Composites
Curved fibres
Finite element
Optimization
Advisor: Steeves, Craig A
The Modern Twig: Extended Techniques for Piccolo

Experimentation with sounds and special effects in the twentieth century have unearthed a new voice for the piccolo, one which has taken the instrument from orchestral coloratura to contemporary virtuoso. The use of piccolo in modern music continues to increase, however the literature lacks a definitive, comprehensive resource outlining the range of extended techniques possessed by the instrument. The Modern Twig offers a brief historical analysis of the piccolo’s rise to soloist status and an extensive set of annotated fingering charts for twenty-two different techniques. Additionally, performance guides for four pieces of contemporary repertoire – Lachrymose by Derek Charke, Diffraction by James Dillon, Nidi by Franco Donatoni and Superscriptio by Brian Ferneyhough – offer piccolo players the practical advice needed to more readily bring these works to life. The piccolo offers composers and performances a dramatic palette of colors and sounds suitable for use in contemporary music. The Modern Twig will serve as an authoritative resource for anyone wishing to write or perform new music for piccolo.

Keywords: Contemporary
Extended Techniques
Flute
Modern
Piccolo
Advisor: MacKay, Gillian
Making 'fritters with English:' Functions of Early Modern Welsh Dialect on the English Stage

The Welsh had a unique status as paradoxically familiar ‘foreigners’ throughout early modern London; Henry VIII actively suppressed the use of the Welsh language, even though many in the Tudor line selectively boasted of Welsh ancestry. Still, in the late-sixteenth century, there was a surge in London’s Welsh population which coincided with the establishment of the city’s commercial theatres. This timely development created a stage for English playwrights to dramatically enact the complicated relationship between the nominally unified nations. Welsh difference was often made theatrically manifest through specific dialect conventions or codified and inscrutable approximate Welsh language. This dissertation expands upon critical readings of Welsh characters written for the English stage by scholars such as Philip Schwyzer, Willy Maley, and Marissa Cull, to concentrate on the vocal and physical embodiments of performed Welshness and their functions in contemporary drama. This work begins with a historicist reading of literary and political Anglo-Welsh relations to build a clear picture of the socio-historical context from which Welsh characters of the period were constructed. The plays which form the focus of this work range from popular plays like Shakespeare’s Henry V (1599) to lesser-known works from Thomas Nashe’s Summer’s Last Will and Testament (1592) to Thomas Dekker’s The Welsh Embassador (1623) which illuminate the range of Welsh presentations in early modern England. From the characterizations of the foolish ‘foreigner’ to the mystical Welsh woman, these characters shed light on sixteenth and seventeenth-century performance conventions. Through close readings of extant dramatic texts, editors’ emendations of dialects, and archival materials from modern productions, this dissertation exposes where the sounds of stage Welsh fit within the social and theatrical continuum of early modern England.

Keywords: Dialect
Early modern London
Language play
Shakespeare
Welsh
Advisor: Astington, John