VictorJuiz/thesis huggingface dataset:
Stereoselective and Stereospecific Interactions with Amino Acids

The following study investigates the intramolecular and intermolecular interactions responsible for invoking stereoselectivity and stereospecificity in the synthesis of a chiral original species and amino acid receptor. The former commences with a brief overview of the nature, scope and applications of helical chirality, and culminates in the formation of a permanent helix via the synthesis of a novel chiral lactone. The latter is discussed as an extension of a naturally occurring cofactor whose identity is modulated to furnish a tailored receptor selective to the binding of amino-acid enantiomers. The study and analysis is executed via both synthetic and computational methods.

Keywords: receptor
enantiomer
amino acid
sensor
lactone
helical
imine
chiral
helix
computation
computational
stereoselectivity
diastereoselective
stereospecific
Advisor: Chin, Jik
A Visual Theory of Natsume Sōseki: the Emperor and the Modern Meiji Man

This thesis explores the affect of the emperor-centred visual culture on Sōseki’s use of visual methodologies in his travel writing in London and Manchuria, as well as his novel Sanshirō. In Part I of this thesis, I argue that Sōseki’s anxiety and ambivalence was in part due to the visual culture created around an imperial image infused with symbolic power. Part II of this thesis is almost a reversal of the first, as it discusses Sōseki’s use of deliberately visual methodologies to express his anxiety and ambivalence towards modernity. In light of my discussion of these complex visual techniques, I conclude by briefly addressing the allegations of Sōseki’s complicity in Japanese imperialism and the (non-)politicization of his work. While Sōseki’s anxiety and ambivalence may have been caused by the extremely visual culture centred on the emperor, it also provided him with a means and methodology for expressing his pessimism.

Keywords: Natsume Sōseki
Meiji
emperor
Japan
Sanshirō
London
Manchuria
colonialism
Michel Foucault
Frantz Fanon
visuality
Advisor: Sakaki, Atsuko
Complex Negotiations at the Kitchen Table: A Qualitative Analysis of Pediatric Home Modifications

Occupational therapists assess and make recommendations for modifying home environments to facilitate caregiving of children in their homes. Children who are profoundly and permanently physically disabled remain dependent for their care throughout their lifespan. As they mature, the physical demands on family members to provide care become more challenging requiring major modifications to ease caregiving. Qualitative interview data of ten educationally influential occupational therapists (EIOTs) were collected to examine what information the EIOTs collect and how they prioritize and organize these data to make modification recommendations. The data were analyzed using grounded theory methodology. The findings detail myriad information required by the EIOT to make recommendations for modifications. Findings suggest a future oriented and highly contextualized information gathering process. The themes were integrated into a process model that suggests how therapists may be developing recommendations. The findings highlight important implications for research, education, clinical practice and service delivery policy.

Keywords: pediatrics
home modification
Occupational Therapy
Assessment
Advisor: Rappolt, Susan
Building a Microsimulation of the Rental Sector in the Greater Toronto Area

This paper presents a microsimulation model of the rental sector in the Greater Toronto (GTA). The main contributions of this research are that it develops a conceptual framework for modeling housing issues and policies, and implements a rental model within the Integrated Land Use, Transport, and Environment (ILUTE) framework developed at the University of Toronto. The key components of the rental model include: (1) the production of rental units; (2) a tenure choice model; (3) a rent setting model; and (4) a rental market model. The rental model is simulated yearly from 1986 till 2006. The preliminary results are presented for the number of households renting, the average rent per census tract, and the number of renter households facing affordability issues. Two areas of future research are proposed that seek: (1) to improve the current model’s accuracy; and (2) to develop a more dynamic model.

Keywords: microsimulation
model
rental
housing
affordability
Advisor: Beck, J. Christopher
Miller, Eric
Dealloying and Synthesis of Nanoporous Pt and Au from AgPt and AgAu Binary Alloys

A study is presented on the synthesis and characterization of nanoporous AgPt and AgAu alloys after annealing and dealloying in 5% HClO4. Dealloying removes the less-noble atom from the alloy surface to produce nanoporous, highly-interconnected ligaments. Voltammetry of AgPt and AgAu shows the critical potential, Ec, at various potential scan rates. Potential hold current decay experiments on Ag-23Pt and Ag-23Au further show the intrinsic Ec to be 275 mV and 290 mV, respectively. Ec was governed by thermodynamic clustering in the alloys as opposed to dissolution-diffusion kinetic effects. EDX shows the starting 77Ag-23Pt material changes composition after dealloying to about 12Ag-88Pt. XRD indicates the presence of ordering in AgPt via a superlattice (100)-peak for a specific anneal treatment. EIS measurements done on as-annealed and dealloyed AgPt and AgAu samples show the onset of bulk porosity and show that capacitance increase is equal for both alloys at two different dealloying potentials.

Keywords: Dealloying
Nanoporous
AgAu
AgPt
Critical potential
Advisor: Newman, Roger C.
C60:LiF Hole Blocking Layer for Bulk-heterojunction Solar Cells

A standard procedure for P3HT:PCBM bulk-heterojunction solar cells has been developed. Fabrication conditions, such as environment; solution concentration, thickness of active layer or post-treatment methods are systematically optimized. The best device performance is obtained by slow-drying spin-coated P3HT:PCBM (1:0.8) blend layer with DCB as solvent. C60:LiF composite films with up to 80% LiF concentration as hole blocking layer have been developed to significantly increase power conversion efficiencies of OPV devices. The short-circuit current density is greatly enhanced, without sacrificing open-circuit voltage and fill factor. Due to its superior oxygen diffusion blocking effect, the C60:LiF composite layer also can provide a more effective passivation film than a thin LiF layer, resulting in an impressive enhancement in air stability of devices.

Keywords: C60:LiF
hole blocking layer
solar cell
Advisor: Lu, Zhenghong
Reach Control on Simplices by Piecewise Affine Feedback

This thesis provides a deep study of the Reach Control Problem (RCP) for affine systems defined on simplices. Necessary conditions for solvability of the problem by open loop control are presented, improving upon the results in the literature which are for continuous state feedback only. So-called reach control indices are introduced and developed which inform on the structural properties of the system which cause continuous state feedbacks to fail. A novel synthesis method is presented consisting of a subdivision algorithm based on these indices and an associated piecewise affine feedback. The method is shown to solve RCP for all cases in the literature where continuous state feedback fails, provided it is solvable by open loop control. Textbook examples of existing synthesis methods for RCP are provided. The motivation for studying RCP and its relevance to complex control specifications is illustrated using a biomedical application.

Keywords: systems control
reachability
simplex
piecewise affine feedback
reach control
biomedical engineering
anesthesia automation
Advisor: Broucke, Mireille E.
Evaluation of a Mobile Platform for Proof-of-concept Autonomous Site Selection and Preparation

A mobile robotic platform for Autonomous Site Selection and Preparation (ASSP) was developed for an analogue deployment to Mauna Kea, Hawai‘i. A team of rovers performed an autonomous Ground Penetrating Radar (GPR) survey and constructed a level landing pad. They used interchangeable payloads that allowed the GPR and blade to be easily exchanged. Autonomy was accomplished by integrating the individual hardware devices with software based on the ArgoSoft framework previously developed at UTIAS. The rovers were controlled by an on-board netbook. The successes and failures of the devices and software modules are evaluated within. Recommendations are presented to address problems discovered during the deployment and to guide future research on the platform.

Keywords: Autonomous Mobile Robotics
Multiagent Robotics
In-Situ Resource Utilization
Autonomous Site Selection and Preparation
Lunar Terraforming
Advisor: D'Eleuterio, Gabriele M. T.
Critical Assessment of Customization Discourse in Information Systems Design

Some argue that we live in an “information age”; others claim that we live in a “knowledge society”. This research suggests we live in an era of adaptable and customizable widgets in which users are no longer passive receivers of ad hoc technological solutions, but active agents controlling the behaviour, content modalities, and multiple technological layers transforming the representation and interpretation of information. This study adopts a critical perspective and examines the meaning of access to information and the pertinence of customization. Specifically, it analyzes how the ISO standard AccessForAll (ISO/IEC 24751, 2008) conceptualizes the customization of e-learning environments. A qualitative approach and discourse analysis are used as a methodological strategy. The research analyzes responses to ten interviews conducted with a diverse group of participants. This foundation provides for a discussion about the challenges of customization design and recommendations for the future development of adaptive and flexible learning environments.

Keywords: information systems design
AccessForAll
customization
universal design
participatory design
inclusive design
adaptability
e-learning
discourse analysis
Advisor: Hockema, Stephen
Retrospective Review of Reports of Non-surgical Paresthesia in Dentistry

Paresthesia is a possible adverse event associated with the administration of local anesthetics in dentistry. The purpose of this study was to analyze the 182 cases of non-surgical paresthesia associated with local anesthetic injection that were reported to Ontario’s Professional Liability Program from 1999 to 2008. Examined case parameters included patient age and gender, type and volume of local anesthetic, site of nerve injury, and other symptoms. All but two cases involved mandibular block injection. From 2006 to 2008 alone, 64 cases were reported; this projects to a reported incidence of 1 in 609,000 injections. For both anesthetic drugs available as 4% solutions, namely articaine and prilocaine, the observed frequencies for reporting were significantly greater than expected (chi-square, exact binomial distribution; P<0.01) based on the distribution of local anesthetic use by Ontario dentists. These data suggest that local anesthetic neurotoxicity may be involved in the development of post-injection paresthesia.

Keywords: Dentistry
Local Anesthetics
Paresthesia
Advisor: Haas, Daniel
Propreity Right to Resolve Current Ethical and Legal Dilemmas

This paper will analyze how a model based upon propriety concepts, specifically the conditional gift, could be utilised to address the current limitations of the legal safeguards that have traditionally been used to protect individuals’ contributing to medical research. The paper outlines three benefits of using the concept of the propriety right in the form of a conditional gift to reform medical research. Firstly the conditional nature of consent embodied in the conditional gift, secondly the persistent nature of rights held in immovable and movable contributed material and finally, the ability to use conditional contribution to distribute the rights of researchers and the participant as well as to ensure that beneficial medical research can continue. The essay will conclude by showing that the conditional gift model may not the only way to reform current legal safeguards; yet it may be one of the best candidates for the role.

Advisor: Lisa, Austin
Development of a Low Cost Swing-phase Control Mechanism

Seven above-knee amputees were fitted with a low-cost prosthetic knee and different low-cost swing-phase setups were clinically assessed. Clinical testing included the 20-meter walk tests utilizing a mobile computer setup connected to a potentiometer and accelerometer mounted on the prosthetic limb. As hypothesized, incorporating friction and a spring system resulted in improved gait function. Of the two spring systems evaluated, the dual spring system performed better than the single spring system resulting in increased walking velocity with decreased maximum flexion and terminal impact. The dual spring system resulted in lower terminal impact because the deactivation of the stiff spring and activation of the less stiff spring during the last 25 degrees of swing-phase before extension allows the shank to decelerate and hit the bumper at a lower velocity. The swing-phase control mechanisms evaluated have the potential to improve prosthetic function and are ideal for use in low-cost and peadiatric prostheses.

Keywords: prosthetics
swing phase
developing countries
terminal impact
mechanical
non fluid
low cost
clinical engineering
biomedical engineering
Advisor: Cleghorn, William L.
Andrysek, Jan
PEM Fuel Cells Redesign Using Biomimetic and TRIZ Design Methodologies

Two formal design methodologies, biomimetic design and the Theory of Inventive Problem Solving, TRIZ, were applied to the redesign of a Proton Exchange Membrane (PEM) fuel cell. Proof of concept prototyping was performed on two of the concepts for water management. The liquid water collection with strategically placed wicks concept demonstrated the potential benefits for a fuel cell. Conversely, the periodic flow direction reversal concepts might cause a potential reduction water removal from a fuel cell. The causes of this water removal reduction remain unclear. In additional, three of the concepts generated with biomimetic design were further studied and demonstrated to stimulate more creative ideas in the thermal and water management of fuel cells. The biomimetic design and the TRIZ methodologies were successfully applied to fuel cells and provided different perspectives to the redesign of fuel cells. The methodologies should continue to be used to improve fuel cells.

Keywords: Proton Exchange Membrane Fuel Cell
Biomimitic Design
Advisor: Wallace, James S.
Shu, Lily H.
Taking Rights Way Too Seriously: Kant, Hohfeld, and Evaluating Conceptual Theories of Rights

This paper concerns the dominant conceptual or formal accounts of legal rights: the Interest and Will Theories. Section II clarifies the minimal necessary conditions for a rights model to count as a Will Theory. It also explores Kant’s Will Theory of rights and the difficulties posed to it by Hohfeld’s schema of jural relations. Kant has three alternatives: reject the schema’s utility or demonstrate his theory’s compatibility with it via molecularist or basic models of Hohfeldian rights. Although his best option is to disavow Hohfeld, Kant’s theory is ultimately undesirable on other grounds. Section III shall analyze the modern Will and Interest Theories’ biggest weaknesses according to a test proposed in Section I, which should generate bases for preferring one theory to another. It will offer a counterargument to the Inalienability charge levied against the Will Theory, and demonstrate why Interest Theory responses to the Third Party Beneficiary argument are inadequate.

Keywords: Legal Theory
Philosophy
Jurisprudence
Rights
Advisor: Benson, Peter
Acquisition Of 3D Ground-Penetrating Radar Data by an Autonomous Multiagent Team in Support of In-situ Resource Utilization

This dissertation details the design and development of a mobile autonomous platform from which to conduct a 3D ground-penetrating radar survey. The system uses a three-rover multiagent team to perform a site-selection activity during a lunar analog mission. The work took place beginning in 2008 and culminated in a final field test on Mauna Kea in Hawaii. This demonstration of autonomous acquisition of 3D ground-penetrating radar in a space robtic application is promising not only for in-situ resource utilization, but also for the concept of multiagent teaming.

Keywords: space robotics
rovers
Ground penetrating radar
GPR
In-Situ Resource Utilization
ISRU
Lunar outpost
lunar rovers
multiagent team
autonomous robotics
Advisor: D'Eleuterio, Gabriele M. T.
Microsphere Kinetics in Chronic Total Occlusions

Chronic total occlusions are a common problem in patients with coronary artery disease. The primary barrier to successful percutaneous coronary intervention is inability to cross the lesion with a guidewire. We seek to characterize polymer microspheres as a controlled delivery mechanism for collagenase and VEGF, novel intralesional therapies being investigated to alter CTO structural properties. Release profiles for protein-loaded PLGA [poly(lactic-co-glycolic acid)] microspheres showed sustained BSA and VEGF release over eight and 48 hours respectively. Polymer degradation products had no impact on endothelial cell growth and protein bioactivity was maintained post-release. In vivo localization of microsphere-released collagenase was not possible due to low concentrations remaining at the site. Histology confirmed microspheres remained in the collagen-dense, proximal 15 mm of the lesion, likely altering the structural integrity of the plaque.

Keywords: Chronic Total Occlusion
Polymer microsphere
Controlled Release
Advisor: Strauss, Bradley
Convergence Results for Rearrangements: Old and New.

The purpose of this thesis is twofold. On the one hand, it aims to give a thorough review and exposition of current best results regarding approximating the symmetric decreasing rearrangement by polarizations and Steiner symmetrizations. These results include those of Van Schaftingen on explicit universal approximation to the symmetric decreasing rearrangement by sequences of polarizations as well as his results on almost sure convergence of rearrangements to the symmetric decreasing rearrangement. They also include those of Klartag and Milman which yield rates of convergence for Steiner symmetrizations of convex bodies. On the other hand, new results are proven. We extend Van Schaftingen's results on almost sure convergence of polarizations and Steiner symmetrizations by showing that the conditions on the random variables can be weakened without affecting almost sure convergence to the symmetric decreasing rearrangement. Lastly, we derive rates of convergence for polarizations and Steiner symmetrizations of Hölder continuous functions.

Advisor: Burchard, Almut
Investigation of Surface Properties and Heterogeneity in Gas Diffusion Layers for Polymer Electrolyte Membrane Fuel Cells

The development of improved water management strategies for the polymer electrolyte membrane fuel cell (PEMFC) could stand to benefit from an improved understanding of the surface and internal structure of the gas diffusion layer (GDL). The GDL is a fibrous porous material enabling mass transport between the PEMFC catalyst layer and flow fields. Fluorescence-based visualizations of liquid water droplet evaporation on GDL surfaces were performed to investigate water droplet pinning behaviours. The heterogeneous in-plane and through-plane porosity distributions of untreated GDLs were studied using computed tomography visualizations. The through-plane porosity distributions were utilized to calculate heterogeneous local tortuosity, relative diffusivity, and permeability distributions. Finally, the heterogeneous through-plane porosity distributions of GDLs treated for increased hydrophobicity were investigated. This work provides new insight into GDL material properties to better inform future PEMFC models.

Keywords: Gas Diffusion Layer
Polymer Electrolyte Membrane Fuel Cells
Advisor: Bazylak, Aimy
Laser Fired Aluminum Emitter for High Efficiency Silicon Photovoltaics Using Hydrogenated Amorphous Silicon and Silicon Oxide Dielectric Passivation

This thesis proposes and demonstrates a hydrogenated amorphous silicon passivated, inverted photovoltaic device on n-type silicon, utilizing a Laser Fired Emitter on a rear i-a- Si:H/SiOx dielectric stack. This novel low-temperature-fabricated device architecture constitutes the first demonstration of an LFE on a dielectric passivation stack. The optimization of the device is explored through Sentaurus computational modeling, predicting a potential efficiency of >20%. Proof of concept devices are fabricated using the DC Saddle Field PECVD system for the deposition of hydrogenated amorphous silicon passivation layers. Laser parameters are explored highlighting pulse energy density as a key performance determining factor. Annealing of devices in nitrogen atmosphere shows performance improvements albeit that the maximum annealing temperature is limited by the thermal stability of the passivation. A proof of concept device efficiency of 11.1% is realized forming the basis for further device optimization.

Keywords: Laser Fired Contact
LFC
a-Si:H
Hydrogenated Amorphous Silicon
DC Saddle Field
Localized Rear Emitter
Advisor: Kherani, Nazir P.
Response Shift Following Surgery of the Lumbar Spine

This study is a prospective longitudinal outcome study investigating the presence of response shift in disease and generic functional outcome measures in 105 patients undergoing spinal surgery. The then-test method which compares pre-test scores to retrospective pre-test scores was used to quantitate response shift. There was a statistically significant response shift for the Oswestry Disability Index (ODI) (p=0.001) and the Short Form-36-PCS (p=0.078). At three months, seventy-two percent of patients exhibited a response shift with the ODI. Fifty-six and 21 percent of patients exhibited a response shift with the SF-36 physical and mental component scores respectively. When accounting for response shift and using the minimal clinically important difference, the success rate of the surgery at 3 months increased by 20 percent. The presence of response shift has implications for the measurement properties of standard spinal surgery outcome measures including the effect size of treatment and the number of responders to treatment.

Keywords: Response shift, lumbar spine surgery, functional outcomes
Advisor: Davis, Aileen M.
Peripherin-28 as a Biomarker of ALS: A Methodological Study

Amyotrophic lateral sclerosis (ALS) is a progressive and fatal neurodegenerative disease which currently lacks rapid and definitive diagnostic tests. Recently identified neuron specific splice variant molecules, Per28 and NFL-60, have been shown to contain unique epitopes and to have altered levels of expression in ALS patients. It is believed that these factors make Per28 and NFL-60 excellent candidate biomarkers for the ALS disease state. In this study, we attempted to develop ELISA assays directed against Per28 and NFL-60, as well as a generalized guideline for splice variant ELISA development, which could be used in a clinical setting. Limitations in currently identified antibodies to the splice variants allowed only for the completion of a Per28 ELISA, which lacked the sensitivity for clinical relevance. This assay creation process, however, did produce a guideline for similar ELISA development, which should allow for the more expeditious creation future ELISA.

Keywords: Peripherin
Neurofilament Light
TDP-34
ELISA
amyotrophic lateral sclerosis
Per28
TDP-43 C-Splice
NFL-60
cerebrospinal fluid
biomarkers
alternative splicing
Advisor: Robertson, Janice