VictorJuiz/thesis huggingface dataset:
The Impact of ROS Scavenging on NMDA and AMPA Receptor Whole Cell Currents in Pyramidal Neurons of the Anoxia Tolerant Western Painted Turtle
Keywords: anoxia
reactive oxidative speecies
NMDAR
AMPAR
western painted turtle
mitochondria
ATP-sensitive potassium channels
calcium
hydrogen peroxide
N-acetylcysteine
N-2-mercaptopropionylglycine
NMDAR redox site
electrophysiological patch clamping
fluorescent microscopy

Extended periods of oxygen deprivation cause brain death in mammals but the western painted turtle overwinters in anoxic mud for months without damage. Neural protection is achieved through decreases in the whole cell currents of N-methyl-D-aspartate and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (NMDAR and AMPAR) that are dependent on a mild increase in intracellular calcium from the mitochondria. The goal of this research was to determine if natural anoxic decreases in reactive oxidative species (ROS) serve as the signal to bring about these changes. Reductions in cellular ROS levels were demonstrated to have no effect on AMPAR currents or intracellular calcium and produced massive increases in NMDAR currents, indicating that ROS depression does not directly mediate anoxic alterations. Interestingly, mammalian neural tissue also experiences a similar increase in NMDAR whole cell current in response to reducing agents suggesting a possible conserved mechanism for normoxic receptor control.
Household Vehicle Fleet Decision-making for an Integrated Land Use, Transportation and Environment Model
Keywords: ILUTE
travel demand modelling
vehicle ownership
TASHA
microsimulation
vehicle fleet

Understanding how households make decisions with regards to their vehicle fleet based on their demographics, socio-economic status and travel patterns is critical for managing the financial, economic, social and environmental health of cities. Vehicle fleets therefore form a component of the Integrated Land Use, Transportation and Environment (ILUTE) modelling system under development at the University of Toronto. ILUTE is a year-by-year agent-based microsimulation model of demographics, land use and economic patterns, vehicle fleet decisions and travel choices in the Greater Toronto and Hamilton Area. This thesis extends previous work that modelled the quantity, class and vintage of vehicles in ILUTE households. This revised model offers three key improvements: transaction decisions are made sensitive to travel patterns, fuel costs are better represented, and vehicle purchases are considered in the context of the overall household budgeting. Results are promising, but further model validation is required. Potential extensions of the research are discussed.
Incorporating Time Domain Representation of Impedance Functions into Nonlinear Hybrid Modelling
Keywords: soil-structure interaction
impedance function
hybrid simulation
seismic response

A number of methods have been proposed that utilize the time domain transformations of the frequency dependent impedance functions to perform time-history analysis of structures accounting for soil-structure interaction (SSI). Though these methods have been available in literature for a number of years, this study is the first to rigorously examine the limitations and advantages of these methods in comparison to one another. These methods contain certain stability issues that required investigating which lead to the formation of an analysis procedure that assesses a transform method’s stability. The general applicability of these methods was demonstrated by utilizing them to model increasingly sophisticated reference problems. Additionally the suitability of these methods to being incorporated into hybrid simulations of nonlinear inelastic structures considering soil-structure interaction was confirmed. The modelling of a nonlinear structure considering soil-structure interaction is an improvement over the most common modelling strategies that model solely linear-elastic behaviour.
The Answer, Not the Problem: An Examination of the Role of Aboriginal Rights in Securing a Liberal Foundation for the Legitimacy of the Canadian State
Keywords: Aboriginal rights
sovereignty
liberalism
legitimacy

Are Aboriginal rights defensible within the framework of liberalism? Liberalism's commitment to individual equality seems to preclude Aboriginal rights insofar as these rights are exercisable by only a sub-set of the Canadian population and not by all Canadians equally. Instead of asking how Aboriginal rights can be justified within the liberal state, we need to question the legitimacy of the state's assertion of sovereignty over Aboriginal peoples and territories. Of the four potentially applicable modes of acquiring sovereignty - discovery, conquest, cession and prescription - only treaties have the potential to provide a liberally-compelling basis for the legitimacy of Crown sovereignty. But historical treaties did not purport to transfer sovereignty. As such, Canadian sovereignty suffers from a normative lacuna. Aboriginal rights, as set out in mutually consensual treaties addressing the sharing of sovereignty, have the potential to fill this lacuna and thereby to ground the legitimacy of Crown sovereignty.
Phylogenetic Structuring of Lake Fish Communities
Keywords: community phylogenetics
aquatic ecology
freshwater fish
habitat filtering

Evolutionary history has been recognized as an important factor in studying ecological communities. Lake fish communities have had limited consideration from a community phylogenetics perspective and present the opportunity to include trophic interactions in the analysis. For the species under study, I used known phylogenies from the literature and genetic information to determine relative branch lengths and phylogenetic relationships by Bayesian inference. Using the resultant phylogenetic tree and fish community data, the phylogenetic community structure was determined for the lakes in the Manitoulin Island and LaCloche regions of Ontario, Canada. Evidence of phylogenetic structuring was found, particularly associated with piscivory, winter hypoxia tolerance, and thermal preferences for deep coldwater lakes. Although the majority of the lakes were weakly structured from a phylogenetic perspective, significant trends were nonetheless apparent; especially when further informed by examining species-specific trends, demonstrating that evolutionary history can play a role in structuring freshwater fish communities.
Improvements to Information Flow in the Physician Order Tracking Process
Keywords: information flow
simulation
mathematical theory of communication
emergency department

In an emergency department (ED), information flow is of high value, as the ability to react quickly directly affects the patients’ well being. One of the gaps in the information flow is in the order tracking process. This paper focuses on modelling the feedback in this process from the order being issued until it has been fulfilled. We address this problem using discrete-event simulation. Additionally, we use the mathematical theory of communication to evaluate the information con- tent in the current and proposed systems. We perform computational tests on these models to compare their performance. Experimental results show that the problem can be effectively modelled using our approach and the effects of feedback on the physician decision-making can be better understood. The results indicate that additions of as little as one point of feedback have practically significant effects on the amount of time that an order spends in the system.
Performance Improvements for Lidar-based Visual Odometry
Keywords: Robotic
Navigation
Lidar
Visual Odometry

Recent studies have demonstrated that images constructed from lidar reflectance information exhibit superior robustness to lighting changes. However, due to the scanning nature of the lidar and assumptions made in previous implementations, data acquired during continuous vehicle motion suffer from geometric motion distortion and can subsequently result in poor metric visual odometry (VO) estimates, even over short distances (e.g., 5-10 m). The first part of this thesis revisits the measurement timing assumption made in previous systems, and proposes a frame-to-frame VO estimation framework based on a pose-interpolation scheme that explicitly accounts for the exact acquisition time of each intrinsic, geometric feature measurement. The second part of this thesis investigates a novel method of lidar calibration that can be applied without consideration of the internal structure of the sensor. Both methods are validated using experimental data collected from a planetary analogue environment with a real scanning laser rangefinder.
Mechanisms of Glucagon-like Peptide-2-mediated Effects on Intestinal Barrier Function in Health and Irinotecan-induced Enteritis
Keywords: GLP-2

Glucagon-like peptide-2 (GLP-2) is an intestinal hormone that promotes gut growth through an insulin-like growth factor (IGF)-1 and intestinal epithelial (IE)-IGF-1 receptor (R)-dependent pathway. GLP-2 also promotes epithelial barrier function by as yet unknown mechanisms. I hypothesized that GLP-2-mediated effects on barrier function requires the IE-IGF-1R. Chronic GLP-2 treatment enhanced barrier function by decreasing gastrointestinal permeability in vivo and increasing jejunal resistance ex vivo. These responses were abolished in inducible IE-IGF-1R knockout (KO) animals. Additionally, epithelial sealing tight junctional proteins claudin-3 and -7 were upregulated by GLP-2 in control but not KO mice. Moreover, IE-IGF-1R deletion induced a shift in occludin localization from apical to intracellular domains. In contrast, in irinotecan-induced enteritis, GLP-2 normalized epithelial barrier function in control animals, but continued to be ineffective in KO mice. Collectively, the effects of GLP-2 on barrier function are dependent on the IE-IGF-1R and involve modulation of the tight junctional complex.
Regression Modelling of Power Consumption for Heterogeneous Processors
Keywords: Power Modelling
OpenCL
Simulation
Benchmarking

This thesis is composed of two parts, that relate to both parallel and heterogeneous processing. The first describes DistCL, a distributed OpenCL framework that allows a cluster of GPUs to be programmed like a single device. It uses programmer-supplied meta-functions that associate work-items to memory. DistCL achieves speedups of up to 29x using 32 peers. By comparing DistCL to SnuCL, we determine that the compute-to-transfer ratio of a benchmark is the best predictor of its performance scaling when distributed. The second is a statistical power model for the AMD Fusion heterogeneous processor. We present a systematic methodology to create a representative set of compute micro-benchmarks using data collected from real hardware. The power model is created with data from both micro-benchmarks and application benchmarks. The model showed an average predictive error of 6.9% on heterogeneous workloads. The Multi2Sim heterogeneous simulator was modified to support configurable power modelling.
Source and Carrier Effect on the Bioactivity of BMP Bio-implants
Keywords: BMP
Bio-Implants

Bone morphogenetic protein-2 (BMP-2) plays a critical role in bone formation. The aim of this study was to compare the activity of the mammalian cell BMP-2 to the E-coli cell BMP-2. In vitro, the potency of mammalian and E-coli BMP-2 was compared by adding BMP-2 to C2C12 cells and measuring the level of alkaline phosphatase activity. In vivo, the activity was evaluated by placing the bioimplants in the thigh muscle of mice, and measuring the amount of bone induced. The in vitro assay clearly showed that mammalian BMP was significantly more potent than E-coli BMP. In vivo, on the calcium phosphate carrier, mammalian BMP produced more bone than E-coli BMP, but E-coli BMP produced higher density tissue than mammalian BMP. On both mammalian and E-coli BMP, the calcium phosphate carrier had a significant effect on the density but not the quantity of bone produced versus the absorbable collagen sponge carrier.
Novel Hydrogen Bonding Organocatalysts: Applications in the aza-Morita-Baylis-Hillman Reaction and Anion Sensing
Keywords: hydrogen bonding
organocatalysis
anion sensing
self assembly
squaramides

Self-assembly is an efficient method for generating large numbers of structurally diverse catalysts for screening. In this work, the method of self-assembly was explored in the construction of bifunctional catalysts, from a chiral aminophosphine, 2-formylphenylboronic acid, and a (thio)urea-containing diol. These catalysts were evaluated by their effect on the asymmetric aza-Morita-Baylis-Hillman reaction. In the second half of this thesis, the hydrogen bonding abilities of different dithiosquaramides were analyzed. As thioureas have been shown to be stronger hydrogen bond donors than ureas, it was hypothesized that dithiosquaramides may also follow a similar trend. Affinities of corresponding squaramides and dithiosquaramides to chloride, sulfate, and tosylate were compared, as well as their abilities to catalyze the Freidel-Crafts alkylation between indole and trans-β-nitrostyrene.
Effect of Gtf2i Gene in Anxiety
Keywords: anxiety
Williams Beuren Syndrome
Dup7q11.23
Gtf2i

Duplication and deletion of a common interval spanning 26 genes on chromosome 7q11.23 cause Dup7q11.23 Syndrome and Williams-Beuren Syndrome, neurodevelopmental disorders with contrasting anxiety phenotypes. The General Transcription Factor 2 I (GTF2I) gene has been implicated in separation anxiety, common in people with Dup7q11.23, and we studied the effects of commonly used anxiolytics on maternal separation-induced USV in mouse models with copy number changes in Gtf2i. Subcutaneous injection of saline affected both USV production and plasma corticosterone levels in a Gtf2i gene-dosage dependent manner. Drugs acting on the glutamate receptors were most effective at attenuating USVs in all genotypes, compared to GABAergic and serotonergic modulators. Brain c-fos expression after separation was reduced by a GABAA agonist, but not a glutamate antagonist. Collectively, these results suggest a potential difference in pain sensitivity based on Gtf2i copy number and implicate the glutamatergic and GABAergic systems in anxiety phenotypes in these two disorders.
The Mineralogy and Geochemistry of the Green Giant Vanadium-graphite Deposit, S.W. Madagascar
Keywords: Vanadium
Geology
Mineralogy
Geochemistry
Madagascar

The purpose of this project was to determine the vanadium bearing ore minerals present at the Green Giant vanadium-graphite deposit in the S.W. of Madagascar owned by Toronto based Energizer Resources Inc. The rocks are mainly quartzofeldspathic gneiss, with alternating bands of hornblende biotite gneiss, marble, granitoid, and amphibolite. Using X-ray diffraction, electron microprobe analysis, and Raman spectroscopy, the vanadium bearing minerals were identified as vanadium bearing rutile, schreyerite, berdesinskiite, karelianite, a member of the karelianite-eskolaite solid solution, V-bearing phlogopite, V-bearing pyrrhotite, V-bearing pyrite, goldmanite, dravite, uvite, actinolite, and unidentified V-sulphide 1, V-sulphide 2, and V-silicate 1. The mineral assemblage present at Green Giant deposit is quite similar to that at Lake Baikal, Russia. Vanadium-bearing phlogopite is primary vanadium host in the deposit, although V-bearing oxides contribute substantially to the total V concentration, even where present in very trace amounts.
The Effects of Event Properties on Age-related Differences in Episodic Memory
Keywords: episodic memory
autobiographical memory
hippocampus
aging

Episodic memory (EM) is disproportionately impaired in normal healthy aging. However, experimental comparisons and literature reviews of the neural correlates of EM across lab-based and naturalistic paradigms reveal significant differences. The current study systematically manipulated the degree of naturalism by testing memory for the same content encoded in a naturalistic vs. laboratory context in order to investigate how memory performance interacts with the properties of the encoding context in younger and older adults. We found that the naturalistic event was subsequently associated with greater overall recognition accuracy, specifically for sequence information, and was associated with a greater contribution of re-experiencing to recognition. We found no significant interaction of normal aging with the event manipulation, but our older sample is currently too small to draw definitive conclusions. Overall, our results suggest that the experimental manipulation of a controlled real-life event is a viable method for studying naturalistic episodic memory.
Slips During Gait on Winter Surfaces: Evaluation of Ice Cleat Design and Slip Definition
Keywords: winter footwear
slips
falls
ice cleats

Current winter footwear provides inadequate protection from slip-related injuries on ice, and there is limited research investigating the optimal design of anti-slip devices. This study examined how ice cleat spike height and position in the heel affect slipping. No differences could be observed between spike conditions, but results demonstrated that heel spikes may prevent slips initiated between heel contact and foot-flat and forefoot spikes may be necessary to prevent foot-flat slips. Further analysis compared slip outcomes measured using two slip onset definitions: 1) heel contact, and 2) the first point of increasing positive heel acceleration. Slip onset defined as time of heel contact overestimated the number of slips and slip distances. These results demonstrate that ice cleats have the potential to protect pedestrians from slipping but some styles available to consumers (i.e. heel spikes only) may not be adequate. Choice of slip definition in footwear evaluations can significantly influence study outcomes.
Investigation of Molecular and Cellular Mechanism of Myelin – Induced Axonal Degeneration
Keywords: Myelin
Axonal Degeneration
JNK
Bax
Neuronal activity

Axon degeneration is a selective elimination of axons, which plays a crucial role during development, injury, and maintenance of neuronal connections. The p75 neurotrophin receptor (NTR) is responsible for maintaining the specificity of neuronal connectivity in parts of the adult brain by inducing the degeneration of aberrantly growing axons into myelinated tracts. The objective of this study is to identify and characterize the signaling pathways used by p75NTR to mediate axon degeneration on myelin. Since p75NTR signals via JNK/Bax/caspase pathway to cause apoptosis, I asked whether this pathway might also be involved in axon degeneration. I observed that inhibition of JNK or Bax significantly decreased myelin-induced axonal degeneration, while depolarization of axons with potassium chloride prevented axonal degeneration on myelin. Together, these results suggest that p75NTR-dependent, myelin-mediated axon degeneration occurs via JNK/BAX signaling, and that neural activity is important for the prevention of myelin-induced axonal degeneration.
Copying Canada - A Critical Analysis of the Barbados Bankruptcy And Insolvency Act
Keywords: Bankruptcy
Insolvency

Barbados enacted the Bankruptcy and Insolvency Act in the year 2001. This Act is based entirely on the Canadian Bankruptcy and Insolvency Act. Barbados reformed its bankruptcy and insolvency laws in order to offer greater protection to debtors while simultaneously protecting creditors from fraud. Additionally, the new reforms were designed to remove the stigma that attaches to insolvent and bankrupt individuals and businesses and to make Barbados a more attractive destination for the creation of and investment in new businesses. Despite the existence of a legislative framework designed to assist debtors and creditors only five matters have been initiated under the Barbados Act. In this thesis I examine why there has been reluctance to rely on the Act. Ultimately, I conclude that the bankruptcy and insolvency regime that exists in Barbados is ineffective and lacks many of the features that are necessary for the efficient administration of bankruptcies and insolvencies.
Alkaline Pressure Oxidation of Pyrite in the Presence of Silica – Characterization of the Passivating Film
Keywords: Pressure Oxidation
Pyrite

Alkaline pressure oxidation, particularly in the presence of trona as additive, can be used to oxidize high carbonate refractory gold ores as it prevents the formation of CO2 in the autoclave. However, the presence of silica in the ore can lead to the encapsulation of pyrite due to the formation of a passive layer. This phenomenon occurs due to the high solubility of silica in alkaline solutions and its subsequent re-precipitation on the reacting pyrite surface. The present study investigated the chemical composition and thickness of the passive layer on a rotating pyrite surface in an aqueous slurry containing silica sand, sodium carbonate and calcium carbonate at 230°C and under 7 bar of oxygen overpressure. Results obtained from XPS and SEM show that a concentration of 2.5 g/L sodium carbonate gave the maximum thickness of passivation on pyrite and that the passive layer consisted primarily of silicates and aluminosilicates.
"A Beautiful Picture of Chaos": La Vía Campesina and the Convergence of Food Sovereignty and Climate Justice
Keywords: food sovereignty
climate change
social movements
hegemony
peasants
La Vía Campesina
climate justice
system change

La Vía Campesina is an international network of peasant farmers that, since 1996, has promoted the concept of food sovereignty. More recently, this collection of over 160 groups worldwide has been connecting this concept with climate justice issues. Drawing on interviews conducted during the 2012 People’s Summit that took place in Rio de Janeiro, and an analysis of the network’s documents, I consider its work in relation to its member organizations and a broader movement tackling the systemic issues that are driving a range of social, economic and ecological crises. I contend that, while many of Vía Campesina’s proposals will require the establishment of intricate processes and systems depending on the geographic, political and cultural context in question, the network is demonstrating that its radical critiques, proposals and decision-making processes may help contribute to a larger counter-hegemonic narrative as a force to counteract global capitalism.
Inter-Strain Differences in Responses to Subarachnoid Hemorrhage in Mice
Keywords: subarachnoid hemorrhage
vasospasm
brain injury
mouse

Spontaneous subarachnoid hemorrhage (SAH) is a form of hemorrhagic stroke that accounts for approximately 7% of all strokes worldwide. Recently, researchers have gained insight into some possible genetic influences involved in the response to SAH. The goal of this study was to investigate the potential contribution of different mouse genetic backgrounds to brain injury after SAH. SAH was induced in 7 inbred strains of mice, and the degree of large artery vasospasm and brain injury was assessed. After 48 hours, SAH mice showed a significant reduction in middle cerebral artery diameter and increased neuronal injury in the cerebral cortex compared to sham controls. The degree of vasospasm and brain injury varied across strains. This data suggests that vasospasm and neuronal injury may not correlate, and that different genetic factors may influence each one. Future investigations may provide invaluable insight into the causes of these inter-strain differences and potential genetic contributors.