VictorJuiz/thesis huggingface dataset:
Investigating the Fundamental Parameters of Cake Filtration using a Gravity Column Device
Keywords: Cake Filtration
Gravity Filtration
Permeability
Porosity
Wastewater filtration

A column device equipped with an imaging system was used to estimate the permeability of filter mesh, and the porosity and permeability of filter cakes formed by the filtration of wastewater. Synthetic wastewater samples containing polyethylene microspheres with mono-sized and bi-modal size distributions prepared and the effect of particle size and its distribution on filter cake permeability and porosity were investigated. Using actual wastewater samples, changes in filter cake porosity and permeability during the gravity drainage process were investigated. Based on the initial slope of the drainage curve, the filter mesh permeability was estimated. A mathematical model was developed based on Darcy's law to predict the drainage rate and the height of wastewater during the column filtration process with an average error of less than 7%. Experimental drainage data collected for various water column heights suggest that cake compressibility may play a role in the drainage of wastewater.
Characterizing the Community Dynamics of the Leaf Microbiome
Keywords: Agriculture
Microbiome
Phyllosphere

The phyllosphere microbiome of seasonal plants is influenced by biological, environmental and ecological factors. To explore the influence of these factors simultaneously and to determine the forces that drive community composition, we sampled leaf communities from common bean (Phaseolus vulgaris), soybean (Glycine max) and Canola (Brassica napus), planted at three different locations at the Koffler Scientific Reserve, over the course of a growing season. Temporal changes had the most significant affect on the community, regardless of host species or location. Precipitation had the most dramatic effect on the Canola microbiome, while soybean and bean communities followed a more predictable pattern of development throughout the summer and were only minimally affected by rainfall. Leaf communities at the beginning of the season were strongly influenced by soil communities. As time passed, the leaf communities differentiated from the soil, becoming less diverse and containing a greater proportion of leaf-adapted and leaf-specific taxa.
Voice and Silence of the Subaltern: Rural Women in the Public Culture of Post-Socialist China
Keywords: documentary films
gender politics
migrant laborers
rural women
subaltern
suzhi discourse

This study examines rural women's self-narrations about their sufferings in post-socialist China both in the official media and in the documentary films. The central question this study asks is whether it is possible for the post-socialist subaltern, such as rural women, to speak. The thesis first demonstrates how the official media efface the voices of rural women by constructing a unified discourse on suzhi or quality development in the post-socialist era. This is followed by an analysis of rural women's writings on their struggles with the official rhetoric channeled through TV documentary programs in the official media. This works concludes with a discussion of the possibility for rural women to speak via the medium of new documentary films. Known as "alternative archives," new documentary films examined rural women's articulations, which in turn can be seen as forms of talking back to the suzhi development discourse.
Endothelial Progenitor Cells for Rotator Cuff Healing
Keywords: Bone-tendon interface
Endothelial progenitor cell
Fibrocartilage
Rotator cuff tendon
Supraspinatus tendon

The avascular environment at the tendon-bone interface is a major concern for rotator cuff healing, contributing to the high re-tear rate. We hypothesized that better tendon-bone healing would occur with transplantation of endothelial progenitor cells, a population of angiogenic cells, during rotator cuff repair in rats. The surgical procedure involved a unilateral detachment and repair of the supraspinatus tendon in a syngeneic population of Fischer 344 rats. The EPC group received one 106 EPCs and the Fibrin (negative control) group received none. Biomechanical and histological analyses were performed at two, four, and six weeks post mortem. At 6 weeks, there was a statistically significant difference in the tendon attachment strength. While no significant difference was found in histology, the EPC groups showed a trend of increased vascularity. The EPCs provide improvements in tendon-bone attachment 6 weeks after the repair. However, such biomechanical improvement was not detectable via conventional histological methods.
Effect of Fear Memory Recall on Interpretation Bias in Rodents
Keywords: Bias
Fear
Interpretation
Memory
Rodent
Touchscreen

Emotions influence interpretation of information. This psychological phenomenon is called interpretation bias. Although rodent studies have established negative interpretation biases due to chronic stressors, the effect of fear memory recall on interpretation bias is still unclear. Therefore, the goal of this study was to investigate the effect of fear memory recall on interpretation bias. We trained mice in a novel visual-based touchscreen paradigm to associate presentation of a large square with a large reward, and small square with a small reward. We then acutely activated a fearful memory through presentation of a tone previously paired with a foot-shock. We tested the effect of acute fear memory recall on following interpretation bias through a paradigm where mice associate ambiguous sized squares with either expectation of a large or small reward. Recall of fear memory did not induce an interpretation bias, but reduced overall motivation and reduced speed to interpret ambiguous stimuli.
Mineral Trioxide Aggregate/Ferric Sulfate Pulpotomy for Vital Primary Incisors: A Randomized Controlled Trial
Keywords: incisors
MTA
primary
pulpotomy
teeth

Purpose: To compare clinical and radiographic outcomes and survival of mineral trioxide aggregate/ferric sulfate (MTA/FS) pulpotomy and root canal therapy (RCT) in carious vital primary maxillary incisors.Methods: Asymptomatic carious vital primary incisors with pulp exposure in healthy children aged 18 to 46 months were allocated randomly to receive MTA/FS pulpotomy or RCT. Clinical and radiographic post-treatment assessments occurred at 6-month intervals for up to 40 months. Two disinterested raters classified each incisor into one of the following radiographic outcomes: N=incisor without pathologic change; Po=pathologic change present, follow-up recommended; Px=pathologic change present, extract.Results: Eighteen-month outcomes demonstrated no statistical difference in clinical or radiographic outcomes for MTA/FS pulpotomy and RCT incisors (P>.05). Survival analysis demonstrated no statistically significant difference in survival for MTA/FS pulpotomy and RCT incisors (P>.05) over a 6 to 40 month follow-up interval. Conclusions: MTA/FS pulpotomy is an effective treatment for carious vital primary incisors.
Population Dynamics Approach for Resource Allocation Problems
Keywords: Evolutionary Dynamics
Game Theory
Optimization
Passivity
Population Games
Water distribution systems

Resource allocation management has become a challenging problem in many aspects all around the world and can be more complicated by high production costs and scarcity of the resources. In this thesis, a water distribution system (WDS), as an example of resource distribution problems, has been investigated. To achieve an adequate level of service to satisfy the demands, the flow of water should be controlled. Here, we utilize a novel game-theoretic approach along with a convex-optimization-based controller to keep the WDS under control. The feedback interconnection of the WDS and controllers reaches an asymptotically stable equilibrium point where its stability analysis uses passivity concepts and the Lyapunov stability theorem for the closed-loop system. Furthermore, an improvement has been made to controllers to make the system robust to reject a certain type of disturbance and to converge to desired equilibrium points in the presence of disturbances.
Exploring Family Perceptions of Weight and Health: A Qualitative Case Study with Parents and Kids
Keywords: communication
health management
parenting
role-modelling
weight management
weight talk

All youth are susceptible to weight-related issues. Little is known about how families navigate weight perception and communication. A multiple case study was conducted with five families to explore parent and child perceptions of health and weight, as well as communication within the home and environment. A within-case analysis identified each family's facilitators and barriers to weight and health, perceptions of weight and health status, and health and weight management. Main themes from the across-case analysis included (i) communication and (ii) parenting/role-modelling. Based on the findings from this study, the importance of considering the family context, identifying the way parents and children communicate with each other and others about health and weight, and the influence of varying types of parenting practices cannot be understated. Taken together, it is clear that parents play a critical role in raising children to be physically healthy and to have positive attitudes about weight.
High-fidelity Aerodynamic Shape Optimization with High-order Spatial Discretization
Keywords: aerodynamic shape optimization
computational fluid dynamics
discrete adjoint
high-order
optimization
summation-by-parts operators

A gradient-based optimization procedure for use with aerodynamic optimization has been developed to make use of high-order analysis. Second-, third-, and fourth-order summation-by-parts operators are used with boundary conditions enforced by simultaneous approximation terms to improve stability. The optimizer has been extensively verified and validated. A matrix-vector product technique is introduced which circumvents the large memory requirements of storing the high-order flux Jacobian matrix. Viscous optimization in two and three dimensions has shown direct benefits to high-order analysis within optimization; accurate analysis can lead to an improved design and is more likely to meet nonlinear constraints when re-evaluated on a very fine mesh. The number of design iterations appears to be unaffected by the order of accuracy. In several cases it has been shown that the third-order method costs nearly the same as the second-order method on a given grid, giving improved accuracy for almost no additional CPU cost.
HDRchitecture: Real-Time Quantigraphic High Dynamic Range (HDR) Imaging on Field-Programmable Gate Array (FPGA) for WearCam (Wearable Camera)
Keywords: Camera
FPGA
HDR
High Dynamic Range
Quantigraphic
Wearable

An important feature of wearable camera systems is that they must work in awide variety of situations under a wide range of lighting conditions. This is truewhether they are used to take pictures, or record video, or even to perform objectrecognition. For these cameras to be used as a real-time seeing aid, we need toproduce High Dynamic Range (HDR) videos at a high frame rate.With the advance of technology in the Field-Programmable Gate Array (FPGA)industry, the increasing number of successful implementations of real-time imagingsystems makes FPGA an attractive platform for prototyping HDR video systemfor wearable computers. In this thesis, an scalable and adaptable frameworkis implemented on FPGA for real-time quantigraphic HDR imaging, for solvingthe camera dynamic range limitation. Most of the implementing issues found inthe essential stages of a typical HDR imaging flow are addressed in detail.
Effect of Feedstock Moisture Content on Biomass Boiler Operation
Keywords: Biomass Boiler
Combustion
Moisture Content
Pulp and Paper

Burning feedstock with high and constantly varying moisture contents is a challenge in the operation of the stoker-grate type biomass boiler in pulp and paper mills. A fundamental two part study was performed to systematically investigate the effect of moisture content on the combustion behaviour of woody biomass. The first part involved a thermogravimetric combustor controlled at different temperatures, and the second part involved collecting and analyzing operating data of 3 biomass boilers. The laboratory results show that combustion occurs through three stages: time-to-ignition, volatile burning, and char burning and samples containing 40% moisture ignite and burn readily at 800°C, but they take longer to ignite at lower temperatures and do not ignite at 400°C. For the field studies, the moisture content of the feedstock was back calculated by a material and energy balance. The relationship between moisture content and the other operating data was studied. The results suggest that changes in moisture content mainly affect the lower furnace temperature and excess O2.
Towards Organoboron-mediated Functionalization of Erythromycin A and Synthesis of its Aglycon
Keywords: antibiotics
borinic
boronic
catalysis
erythromycin
erythronolide

Many natural products, including antibiotics, are structurally complex and contain a wide variety of functional groups. As a consequence, the selective functionalization of these molecules often requires the use of inefficient protecting group strategies. Inspired by this obstacle, our group recently developed a borinic acid-catalyzed method to regioselectively functionalize the equatorial position of cis-vicinal diols in carbohydrates with limited use of protecting groups.The work presented in this thesis describes progress made towards selective functionalization of the cis-vicinal diol present in the macrolide antibiotic erythromycin A. This was attempted using the boronic and borinic acid-mediated methodologies developed previously in our group. Finally, a semisynthesis of erythronolide A was carried out with the goal of using our methodology to prepare novel analogues for biological evaluation.
Structural Features in Heat Transfer Modeling of PEM Fuel Cell Materials
Keywords: Atomic Force Microscopy
Energy
Modeling
Nanoscale
PEM Fuel Cell
Thermal Resistance

In this thesis, the impact of incorporating high resolution structural features into the thermal modeling of the polymer electrolyte membrane (PEM) fuel cell gas diffusion layer (GDL) and microporous layer (MPL) is studied. Atomic force microscopy (AFM) has been used to image the surfaces of untreated Toray GDL fibres, and the nano-sized particles within Sigracet MPL. The validity of the GDL smooth fibre assumption commonly employed in literature is studied using a thermal resistance network approach. The MPL, which has been found to show structural variability between manufacturers, was also analyzed using AFM to obtain distributions for the particle size and filling radius. The equivalent thermal resistance between MPL particles was computed using the Gauss-Seidel iterative method, and was found to be sensitive to the particle separation distance and filling radius. Finally, unit-cell analysis is presented as a methodology for incorporating MPL nano-features into modeling of the MPL bulk regions.
Pediatric Population Reference Value Distributions for Cancer Biomarkers: A CALIPER Study of Healthy Community Children
Keywords: Pediatric
Reference Intervals
Tumor Markers

As part of CALIPER program, a national research initiative aimed at closing the gaps in pediatric reference intervals, I sought to develop a database of covariate-stratified reference intervals in children for 11 circulating tumor markers in accordance with CLSI C28-A3 guidelines. Healthy children from birth to 18 years were recruited to participate in CALIPER and serum samples from 400-700 subjects were analyzed on the Abbott Architect ci4100 TM. Significant fluctuations in biomarker concentrations by age and/or gender were observed in 10 of 11 biomarkers. Age partitioning was required for CA 15-3, CA 125, CA 19-9, CEA, SCC, ProGRP, Total Free PSA, HE4 and AFP, and gender partitioning was required for CA 125, CA 19-9, Total Free PSA. The establishment of these reference intervals will aid in harnessing the full potential of tumor markers in a pediatric population and in research aimed at determining the clinical value of these markers.
Mechanical and Embedded Systems Design for Generic Nanosatellite Bus Spacecraft
Keywords: CanX-45
CNAPS
Cold-gas
Firmware
Nanosatellite
Propulsion

The adaptation of the University of Toronto Space Flight Laboratory Generic Nanosatellite Bus (GNB) mechanical design to Earth-observation and communications applications is investigated. The ability of this bus to expand the capabilities of low-cost nanosatellites by accommodating large pre-deployed payload appendages, such as antennas, is demonstrated. In addition, the operational architecture of a cold-gas nanosatellite propulsion system, enabling small satellite constellations and formation flying, is described. Component testing of this system has validated compliance with subsystem requirements. Lastly, the design and development of a multi-mission embedded systems generic firmware is described. This firmware consolidates common and critical software functionality, greatly reducing both the risk and cost of developing software for new embedded systems. The firmware has been designed for a distributed-node microcontroller bus architecture in general, and the Nanosatellite for Earth Monitoring and Observation (NEMO) bus and Generic Nanosatellite Bus in particular.
The Classifying Work of Immigration Policies in Canada: A Critical Analysis of the Temporary Foreign Workers Program and Access to Settlement Services
Keywords: Bowker and Star
Canada
Classification
Immigration
Settlement services
Temporary Foreign Workers Program

In this thesis I analyse the Canadian Temporary Foreign Workers Program (TFWP) through the lens of Bowker and Star's classification theory. I connect the pervasive abuse and exploitation of temporary foreign workers in Canada to an immigration classification scheme that I argue favours particular economic interests of Canadian employers and workers over the interests of temporary foreign workers. To this end, I outline the nature of the TFWP discussing how employer-centric program intentions shape program structures. In turn, I argue that these structures shape the lives of migrants in Canada by restricting the rights, opportunities, and protections they have in Canada. To illustrate this, I discuss the use of immigration classifications to designate eligibility to receive settlement services in Canada.
Prostate Cancer as a Metabolic Disease - Is Prostate Cancer Diagnosis Associated with Worse Cardiovascular Outcomes?
Keywords: Cardiovascular disease
Metabolic syndrome
Propensity score
Prostate cancer

Metabolic syndrome (MetS) and prostate cancer (PC) share several risk factors. In addition to increased cardiovascular risk, there is evidence that men with MetS have an increased PC risk. Given that both diseases develop over decades, PC diagnosis may precede the onset of MetS, and may be an early indicator of cardiovascular risk. We sought to determine if PC diagnosis is associated with increased risk of subsequent cardiovascular event. In our population-based study using administrative databases, men with PC identified using the Ontario Cancer Registry were hard-matched and propensity score-matched to men without PC diagnosis identified using the Registered Persons Database. Competing risks analyses were performed to compare risk of cardiovascular events. Contrary to our hypothesis, men with PC were less likely to experience a cardiovascular event compared to men without PC (sub-distributional HR=0.92, 95%CI=0.88-0.96). The difference was not clinically significant. Selection bias and confounding may explain this unexpected result.
Design and Implementation of a Feedback Control System for the Ex Vivo Expansion of Hematopoietic Stem Cells
Keywords: hematopoietic
stem cell

Hematopoietic stem and progenitor cell (HSPC) transplantation provides a curative stem cell therapy for hematological pathologies. Umbilical cord blood (UCB) is an attractive source of these cells, and ex vivo expansion would make these cells available to more patients. This endeavor is challenged by the accumulation of endogenously produced signaling factors in vitro, limiting HSPC expansion. We hypothesized that regulating these factors in real time with a feedback control system would enhance expansion. We combined a novel protein quantification assay with a fed-batch bioreactor system to dilute soluble factors, reducing their impact and improving expansion. We developed a mathematical model to further investigate the impact of feedback control on HSPC culture, and used it to design a sophisticated control algorithm to maximize the volumetric efficiency of the fed-batch culture system. This use of feedback control for stem cell culture provides an important step towards a robust bioprocess for HSPC expansion.
Cu@Cu2O@CuO Graded Nanowire Heterostructures for CO2 Reduction
Keywords: CO2 reduction
fuel
nano materials
solar

Cu@Cu2O@CuO graded nanowire heterostructures were successfully synthesized from Cu nanowires (NWs) by thermal oxidation in air. The oxidation level and amount of Cu, Cu2O and CuO in this nanostructure could be controlled by applying different reaction temperatures and times. This heteronanostructure is shown to have a metal-core and an oxide-corona structure. Moreover it has excellent optical absorption in the visible region which is a valuable material characteristic for driving light assisted reactions for CO2 reduction. Coated with δ-FeOOH as co-catalyst, the Cu@Cu2O@CuO@δ-FeOOH NWs show CO2 catalytic activities with a maximum carbon monoxide (CO) production rate of 631.3 nmol g-1 hr-1 at 150°C reduced by H2 in the dark. In the presence of light, surprisingly the CO production rate goes down but the cause of this photo-deactivation phenomenon will draw interest for further study.
Art Around the Belly: Tracing the Cultural Significance and Artistic Value of Belt Hooks in Ancient China
Keywords: Artifact
Belly
Belt Hooks
China
ROM
Royal Ontario Museum

The belt hook was used to fasten garments in ancient China long before the existence of belt buckles or plaques. Its use first appeared more than five thousand years ago and can be prevalently observed in paintings, on statuettes, and even on the famous Terracotta Army. Although it was such a common personal ornament, little has been written on this subject. My thesis will explore, through excavation data, coupled by my research on the extensive collection of belt hooks at the Royal Ontario Museum, how the examination of these ancient Chinese ornaments can not only reveal the status and wealth of its wearer, but also the cultural complexities and social advancements of that time.
Effects of Long Term Memory on Auditory Spatial Attention
Keywords: auditory
long term memory
magnetoencephalography
memory cue
spatial attention

We examined how associations between real world auditory scenes and the location of an embedded auditory target influence spatial attention after a delay period. Healthy young adults (N= 16) formed strong memories for spatial locations of targets within sound scenes, which biased attention one hour later. Participants showed gains in reaction time (100ms) and accuracy (12% increase) to locate targets proceeded by valid memory cues (scenes for which target-context associations were formed) compared to neutral cues. We also found a positive relationship (r =.55, p
The Temporal Trends and Fish Consumption Advisories of Mercury and PCB Contaminants in Lake Trout and Walleye from Lake Ontario, Canada
Keywords: Bayesian Inference
Dynamic Linear Modeling
Fish Consumption Advisories
Multilevel/Hierarchical Modeling
PCB and Mercury Contamination
Prey-Predator Interactions

The first part of our study evaluates the temporal and gender specific trends of the two contaminants in walleye