VictorJuiz/thesis huggingface dataset:
Palynology of the mid-Cretaceous Mattagami Formation and correlative sediments of Ontario

The Mattagami Formation, located to the southeast of Hudson Bay, consists of carbonaceous shales and siltstones, lignites and well sorted quartz sands. These sediments represent a low gradient fluvial-paludal depositional system in an isolated intracratonic basin, which was deposited over 800 kilometers from the nearest marine sediments of the western interior. The age of the deposit is palynologically determined as Middle to Late Albian. Five palynozones are erected and can be used to correlate within the formation. The depositional environment is interpreted as freshwater, low gradient fluvial wetlands in a warm temperate climate. A rich terrestrial palynoflora, including a diverse assemblage of algal palynomorphs, was recovered. The assemblage is freshwater and contains one of the earliest occurrences of freshwater dinoflagellates, represented by 2 ceratioid genera, predominantly Nyktericysta and less frequently Balmula. Zygnematacean zygospores are represented Ovoidites, Lecaniella, and cysts comparable to zygospores of recent Mougeotia. Botryococcus is ubiquitous. Freshwater algal cysts of unknown botanical affinity are represented by Schizosporis and Cymatiosphaera. Three families of freshwater algae are are recognized for the first time from pre-Tertiary sediments: Coelastraceae, Oedogoniaceae, and Sphaeropleaceae. The Mattagami Formation fulfills a rigorous set of criteria that demonstrate deposition in a freshwater paleoenvironment. The occurrence of ceratioid dinoflagellates in this freshwater deposit implies that they alone are not a positive indicator of marine conditions. The freshwater paleoecological affinities of Pediastrum, Botryococcus, Schizocystia, Tetraporina, and Cymatiosphaera, which in the past were associated, in part, with marine environments, are strengthened. (Abstract shortened by UMI.)

Keywords: Palynology, Ontario
Staying on the 'straight path': a critical ethnography of Islamic schooling in Ontario

This study provides a critical ethnographic examination of 4 full-time Islamic schools in order to examine the social, pedagogical and ideological functions of these alternative, religiously-based educational institutions in Canada. This research is based on the following three objectives: (1) identifying the role and function of Islamic schooling in a diasporic context, (2) understanding the role of Islamic education in the development of Islamic identity, (3) examining the Islamization of knowledge and pedagogy in Islamic schools. The discursive socialization and educational practices of Islamic schools also serve to structure gender roles in the Muslim community. The socialization of Muslim girls in particular is implicated by the contested notion of gender identity in Islam. Muslim girls must negotiate various orientations and articulations of identity that both challenge and affirm traditional notions about Islamic womanhood, as well as facing situations of "gendered Islamophobia" outside of schools. For religiously oriented families, Islamic schools provide a more seamless transition between the values, beliefs and practices of the home and school environment. They also provide a space free from racism and religious discrimination that many students encounter within public schools. This study also examines the epistemological foundations for Islamically-centred education and the pedagogical strategies, including methods of discipline and socialization. These aspects of knowledge, pedagogy and practice are examined in order to better understand how they are informed by the religious and spiritual traditions of Islam. Operating as a spiritually-based alternative to the public education system, independent Islamic schools take on multiple sociological roles. For example, these schools attempt to create a "safe" environment that protects students from the "de-Islamizing" forces in public schools and society at large. Some parents choose Islamic schools for children who have become engaged in un-Islamic behaviours such as alcohol or drug use, gang activities or sexual promiscuity. In these circumstances the schools function as spaces for the re-socialization and rehabilitation of wayward youth. Islamic schools therefore also operate as sites for the social reproduction of Islamic identity.

Keywords: Islamic education, Ontario
Muslim girls, Education
Muslim girls, Ontario
The rolling sphere problem

The optimal control problem concerning the sphere Sn rolling without slipping on n-dimensional Euclidean space En (n ∈ [special characters omitted]) is investigated. The differential equations governing the behaviour of the sphere constitute a sub-Riemannian distribution on the Lie group G = [special characters omitted]. The form of the distribution is exploited using Noether's Theorem to derive a family of integrals of motion for the system. This family is then employed to prove that all optimizing trajectories are the projections of normal extremals. An additional family of integrals is also discovered which evokes memories of the Manakov integrals of motion for the free rigid body problem. This family, along with the afore-mentioned family and an extension theorem, is utilized to prove the complete integrability of the rolling sphere problems for n = 3, 4. It is then shown that the equations describing the curvature and torsion of solutions to the Euler-Griffiths elastic problem on E3 are the same as those for a subclass of solutions to the rolling sphere problem with n = 3. The similarity between the rolling sphere problem for n = 3 and the symmetric elastic problem is also discussed.
Characterization of the linear and nonlinear absorption dynamics of aluminum gallium indium arsenide strained-layer multiple-quantum-well semiconductor optical amplifiers

This thesis reports on the experimental characterization of novel AlGaInAs strained-layer multiple-quantum-well (SLMQW) semiconductor optical amplifiers (SOAs), for application in ultrafast semiconductor all-optical switching devices. Facilities constructed for performing pump-probe characterization of the temporal dynamics of active semiconductor waveguide devices, which use a picosecond-pulse Ti:sapphire pumped optical parametric oscillator, are demonstrated. Characterization of two important properties of the SLMQW SOAs is then reported: the ultrafast absorption/gain dynamics, and two-photon absorption (TPA) coefficient. The ultrafast dynamics are found to match with expected results from the literature, exhibiting free carrier step responses as well as two-photon absorption and carrier heating dynamics. A free carrier recovery time constant of sim;132 ps is measured, and a dynamic with a time constant of 3.7 ps attributed to carrier heating. The TPA coefficient alpha 2 is found to be 260--415 cm/GW over the 1500--600 nm telecommunications wavelength range. The relatively long carrier decay lifetimes and high TPA of these SOAs indicate they do not represent a significant improvement for all-optical switching, leaving room for additional work to improve SOA designs.
The role of p73 in ependymoma tumourigenesis

Ependymoma is the third most common paediatric brain tumour, yet specific genetic aberrations that contribute to its pathogenesis have previously eluded identification. We have analyzed a large collection of ependymomas (n=212) using a high resolution SNP genotyping array. We identified an amplification event that encompasses an N-terminally deleted portion of TP73. The TP73 gene gives rise to multiple functionally distinct protein isoforms, encoding both putative tumor suppressor and putative oncogene isoforms, TA and Delta-N isoforms respectively. We have identified a subset of ependymomas that display over-expression of the Delta-Np73 isoforms. This up regulation may be attributed to loss of normal methylation at promoter 2 of TP73, as we have also identified a subset of ependymomas that display hypomethylation in the region of promoter two. Our results suggest that an imbalance in the expression of the oncogenic and tumor suppressor isoforms of p73 may contribute to the pathogenesis of ependymoma.
Characterisation of a Mycobacterium marinum whiB4 mutant

I have generated a whiB4 transposon mutant in Mycobacterium marinum, a model organism for the causative agent of tuberculosis, M. tuberculosis. Sequence homology suggests that whiB4 encodes a putative transcription factor, WhiB4. At the microscopic level, whiB4 mutant bacilli undergo abnormal intercellular aggregation and associate with an unidentified material in the extracellular milieu suggesting that cell wall surface chemistry has been modified from the wild type. There is biochemical evidence suggesting that the relative abundance of cell wall glycolipids, including the phosphatidylinositol mannosides, is disrupted in the mutant. The whiB4 mutant also displays defective entry into macrophages, but once inside the host cell, it appears to grow at a rate similar to wild type. Additionally, I have expressed a histidine-tagged WhiB4 in E.coli for future studies aimed at determining which genomic regions physically associate with the putative transcription factor.
Job loss as career growth: Predictors and outcomes of career exploration and job search during involuntary career transition

In this study, career exploration and job search are examined as coping strategies during involuntary career transitions. The study highlights the role of career exploration for individuals facing career transitions later in life and, most importantly, the potential of career exploration to lead to better quality of jobs upon reemployment and more perceived career growth. The focus of this study is on the three career-related predictors of job search and career exploration, referred to as career-orientation variables: (1) career identity salience, (2) career field tenure, and (3) occupational commitment. In addition, the study also includes some situational and dispositional predictors that are commonly examined in the job loss literature, namely, two types of coping resources, appraisal of job loss and personality characteristics. It is proposed here that career exploration will be of particular benefit to individuals in career transition, as they may employ exploration as a means of coping with and adjusting to a shifting set of challenges posed by unemployment. Lastly, the study examines several reemployment quality outcomes (job improvement, career growth, time unemployed and turnover intention) and posits that those who engage in career exploration possibly in addition to job search during their transition will be more likely to benefit upon reemployment.

Keywords: Human resouce management
Organizational behavior
Dissertations, Academic, Canada
Extractable organochlorine in fish downstream from bleached kraft pulp mills: occurrence, chemical nature and sources

Extractable organochlorine (EOCl) was measured in fish taken from two regions: the Moose River Basin in northern Ontario and the Northern River Basins Study area in northern Alberta, in particular downstream from bleached kraft pulp mills and at relevant reference sites. Statistical analysis of the survey data showed that technology upgrades at the mills such as elemental chlorine-free bleaching, oxygen delignification, and biological treatment have led to a significant decrease in EOCl in downstream fish, eventually resulting in levels close to the background in the regions. A study of the chemical nature of fish EOCl started with gel permeation chromatography, which indicated that the major EOCl compounds were chlorinated fatty acids, probably present in fish in the form of glycerolipids including triglycerides and phosphoglycerides. Several analytical methods were developed for the analysis of traces of chlorinated fatty acids in a matrix of nonchlorinated fatty acids: (1) gas chromatography using a halogen specific detector; (2) high performance liquid chromatographic fractionation for efficient enrichment of target analytes; (3) negative chemical ionization mass spectrometry of pentafluorobenzyl esters for identifying unknowns; and (4) mass spectrometry of 4,4-dimethyloxazoline derivatives for locating the chlorine in dichloro fatty acids. The study shows that threo-5,6-dichlorotetradecanoic, threo-7,8-dichlorohexadecanoic and threo-9,10-dichlorooctadecanoic acids are predominant components in fish collected downstream from bleached kraft pulp mills, while they are undetectable in reference fish samples. The EOCl mass balance indicates that these three components represent about 30% of total EOCl in extracts, of which threo-5,6-dichlorotetradecanoic acid accounts for 60–70%, threo-9,10-dichlorooctadecanoic acid for 19–24%, and threo-7,8-dichlorohexadecanoic acid for 11–16%. The findings support the working hypothesis that, among chlorinated compounds discharged from bleached kraft pulp mills, threo-9,10-dichlorooctadecanoic acid, presumably generated in chlorine-based bleaching processes, is the most bio-accumulative in fish, and that it can be biodegraded by fish into dichlorohexadecanoic and dichlorotetradecanoic acids, presumably via β-oxidative metabolism. These three dichloro fatty acids were identified in suspended solids isolated from biologically treated final effluent discharged from a pulp mill using 50% ClO2 substitution. The effluent-related source of chlorinated fatty acids in downstream fish was thus confirmed.
Modeling of expansion and collapse of extruded filamentary foam through cell-to-cell diffusion

Owing to a small cell size, high cell population density and uniform cell size distribution, microcellular polymeric foams have a variety of industrial applications. To develop innovative foaming technologies, a fundamental understanding of expansion and collapse of extruded filamentary foam is essential. Since computer simulation is capable of uncovering intrinsic details which are hard to acquire either experimentally or analytically, this thesis developed a theoretical model to simulate foam expansion and collapse outside a filamentary extrusion die. This model consists of three stages. In the first stage, foam expansion was made up of polymer swelling and expansion of bubbles. The polymer swelling was characterized experimentally whereas the expansion of bubbles was acquired by integrating growth of each cell. The growth of a single cell was simulated using cell model. In the second stage, a layer-to-layer model was established. It separated the circular extrudate into many concentric cell bands. Each band was made of a transformed gas layer and the surrounding polymer layers. After a set of governing equations were solved, the foam expansion could be estimated. The third stage emerged once the extrudate reached its maximum expansion. In this stage, all the blowing agents within polymer matrix had been depleted. But the blowing agents kept escaping into the surroundings, leading to foam contraction. Consequently, the mechanism of foam expansion and collapse was comprehended. As well, experimental research was implemented to validate the developed model. Meanwhile, to understand cell-to-cell diffusion fundamentally, this thesis undertook a finite element analysis to investigate cell coarsening between two micro-cells and among nine nano-cells, respectively. The effects of system parameters on cell-to-cell diffusion were examined. Furthermore, this thesis used cell-to-cell diffusion concept to predict long-term thermal insulation performance of polystyrene foam boards. The Mie Theory was utilized to calculate radiative conductivity. A transient cell-to-cell diffusion model was employed to describe the decay of blowing agents. A cubic-parallel-series approach was applied to determine thermal conductivity of the gaseous phase and polymer matrix. Effects of foam geometry and blowing agents on thermal insulation capacity were analyzed. Finally, concluding remarks were presented and future work was recommended.
Nonlinear elastodynamic analysis of low tension cable using a new beam element

In this work, an accurate and computationally efficient three-noded curved beam element is developed for the three-dimensional analysis of large displacement and rotation. Consistently coupled polynomial interpolations of element displacement fields are used to eliminate membrane locking and ensure faster convergence rate. Due to its efficiency and reliability, the Predictor-Corrector time integration scheme with a Newmark time stepping algorithm is adopted to solve the equation of motion of low tension cables. A computer program for nonlinear elastodynamic analysis of low tension cables with the newly developed curved beam element is developed by the author using FORTRAN-95 programming language. Numerical results involving quasistatic and dynamic examples are presented to demonstrate the superior accuracy and the high convergence rate of the newly developed curved beam element. The program is further validated by experiments involving an instrumented free swinging steel cable. High speed imaging and strain gauge bridges are used to record the time histories of the cable position and tension. Good agreements in cable position and tension are observed between the experimental results and the finite element predictions. Finally, the developed computer program is applied to a typical low tension cable system involving aerial refuelling hose and drogue. The numerical predictions are compared with existing simulations. It has been shown that the newly developed curved beam element and the computer program are accurate and stable, and capable of providing an robust alternative to existing commercial codes in analysis of aerial refuelling. These newly developed codes should provide designers with a powerful tool for treating low tension cable problems, especially for the snap or slack cables. The design and construction of low tension cable systems require rigorous geometric nonlinear analysis. Current analyses are mostly based on an oversimplified string theory, which treats the cable as a slender tension member only, and the finite difference method. The string theory becomes singular when the tension disappears anywhere in the cable. To avoid the problem of singularity, the beam theory is required to model the low tension cables with a stable and accurate numerical time integration algorithm.
High-bandwidth data dissemination in overlay networks

Data dissemination or multicast in overlay networks, in its various forms, is popular in the Internet because of its lack of infrastructure requirement and its flexibility. Availability of abundant capacity in the physical network and high demand for the exchange of increasingly large-sized data contents make data transfer rate or bandwidth a critical metric to improve. We study application-layer data dissemination in overlay networks, with the aim of reliably maximizing the bandwidth. Our research was undertaken from mainly three fronts. (1) We applied the theoretic results of network coding, from the field of information theory, to overlay multicast. A distributed algorithm is designed to construct an overlay multicast topology conducive to network coding. On this topology, we then devised a practical method for generating specific linear codes to implement the encoding/decoding of data. The resulting overlay multicast topology, with the implementation of network coding, is able to achieve the improvement in bandwidth predicted by the theory. (2) To address practical issues of network dynamics and cross traffic fluctuations, we developed a distributed algorithm to adaptively and progressively build overlay multicast topologies of a multiple-tree structure. We not only conducted experiments in simulations, but also implemented the algorithm and deployed it in PlanetLab, a real wide-area overlay network test-bed. (3) Studying overlay networks from a more theoretical perspective, we made the simple observation that overlay links have hidden correlations in capacity, based on which we introduced a new model of overlay networks: overlay with linear capacity constraints (LCC). We investigated several classical network flow problems in the context of LCC-overlays. Using theory and techniques from the field of linear optimization, we formulated and solved these problems. We also studied LCC-overlays with simulated experiments, and discovered that even a highly restricted class of LCC would yield substantial increase in flow rates. Even more encouraging is that this particular restricted class of LCC is naturally distributed. Furthermore, we developed distributed algorithms both for constructing LCC-overlays and for doing overlay multicast in them.
Solubilities of iron, aluminum, magnesium and nickel in sulfuric acid media between 230 degrees and 270 degrees C

Nickeliferous laterite pressure leachates are multicomponent metal sulfate solutions containing excess free H2SO4 in amounts dependent on the ore and consequently on the solution composition. These solutions are encountered in the Pressure Acid Leach Process for nickel and cobalt recovery from lateritic ore deposits. Typically the metals which have the greatest influence on the leach solution acidity are iron, aluminum, and magnesium. These also have a significant impact on scale formation on the internal surfaces of the autoclave. Solubility data have been extensively used to identify the chemistry and thermodynamics of aqueous solutions. However, very limited data exist for metal solubilities in sulfuric acid media at the temperatures of relevance to laterite pressure leach solutions. In this work, the solubilities of iron, aluminum, magnesium and nickel in 10–70 g/L free sulfuric acid in the temperature range of 230° to 270°C were measured. With the aid of the OLI software, new thermodynamic data were estimated that permit the calculation of the activity of hydrogen ions.
Influence of the tributary system on sculptures in the Tang Dynasty

In the Tang dynasty, China built relations with many countries via the tributary system. Both the Tang and many foreign states benefited by the tributary system politically and economically. Sculptures of foreign rulers as well as exotic animals in the Tang emperors' mausoleums reflected the role of the tributary system in dealing with foreign relations during the Tang dynasty and the development of the tributary system. According to archaeological evidence, ceramic figurines representing foreigners were popular burial objects. These small sculptures vividly depicted foreigners from central Asia and other parts of the world in a realistic style. These sculptures of foreigners are not just an indication of the foreign influence on art and society in the Tang dynasty as is commonly believed; they also reflect the burial custom and the Chinese view of foreigners during this period.
Advanced structural foam injection molding technology: Use of a very low BA content for fine-celled HDPE foams

This thesis presents an innovative structural foam injection molding technology for production of HDPE fine-celled. Structural foam products are widely used because of lightweight and superior strength-to-weight performance. However, structural foam products suffer some drawbacks. The purpose of this research is to develop a new technology to overcome these limitations. The basic strategies for producing a fine-celled foam with uniform cell structure are: (a) to maintain homogeneous single-phase solution; (b) to adopt an effective nucleating agent, and (c) to maintain a certain pressure-drop rate. The strategy used in this study to improve surface quality is to use a very small amount of blowing agent to prevent premature foaming during filling. The effects of processing and material parameters on foam morphologies have been thoroughly studied. Finally, uniform fine-celled HDPE foams with a cell density of 107 cells/cm3 have been successfully achieved.