VictorJuiz/thesis huggingface dataset:
Basis Functions With Divergence Constraints for the Finite Element Method
Keywords: finite element method
computational electromagnetics
basis functions
spurious modes
resonant cavity

Maxwell's equations are a system of partial differential equations of vector fields. Imposing the constitutive relations for material properties yields equations for the curl and divergence of the electric and magnetic fields. The curl and divergence equations must be solved simultaneously, which is not the same as solving three separate scalar problems in each component of the vector field. This thesis describes a new method for solving partial differential equations of vector fields using the finite element method. New basis functions are used to solve the curl equation while allowing the divergence to be set as a constraint. The basis functions are defined on a mesh of bricks and the method is applicable for geometries that conform to a Cartesian coordinate system. The basis functions are a combination of cubic Hermite splines and second order Lagrange interpolation polynomials. The method yields a linearly independent set of constraints for the divergence, which is modelled to second order accuracy within each brick. Mesh refinement is accomplished by dividing selected bricks into 2 × 2 × 2 smaller bricks of equal size. The change in the node pattern at an interface where mesh refinement occurs necessitates a modified implementation of the divergence constraints as well as additional constraints for hanging nodes. The mesh can be refined to an arbitrary number of levels. The basis functions can exactly model the discontinuity in the normal component of the field at a planar interface. The method is modified to solve problems with singularities at material boundaries that form 90° edges and corners. The primary test problem of the new basis functions is to obtain the resonant frequencies and fields of three-dimensional cavities. The new basis functions can resolve physical solutions and non-physical, spurious modes. The eigenvalues obtained with the new method are in good agreement with exact solutions and experimental values in cases where they exist. There is also good agreement with results from second-order edge elements that are obtained with the software package HFSS. Finally, the method is modified to solve problems in cylindrical coordinates provided the domain does not contain the coordinate axis.
STEPS TO PARNASSUS: The Effects of Guided Practice On Junior and Intermediate School Musicians
Keywords: music education
practicing
metacognition
self-regulated learning
practice pedagogy
motivation

Practicing is an ineluctable component in the pursuit of achieving musical goals. This is particularly true in the Western model of music education that is, for the most part, characterized by private lessons or ensemble rehearsals that typically occur only once each week. How dependent is the motivation to learn music on effective practicing? Novices often abandon music education simply because “it’s too hard.” Is the frustration the result of a lack of success due to ineffective practicing? Effective practicing evolves naturally with increased musical knowledge and expertise. Overall, a musician’s development towards effective practicing may be described as the acquisition of a metacognitive awareness of one’s own learning and hence a more active participation in that learning that is characterized by self-regulatory behaviours. This research asks if guided practice at an early age might prove a catalyst in the development of effective practicing which naturally occurs with musical expertise. Over the course of an academic school year, 13 novice musicians engaged in guided practice sessions with the researcher. The participants were private piano students and young band members. Data gathered through interviews, questionnaires and video recordings of lessons and practice sessions at the musicians’ homes were analyzed within the theoretical framework of self-regulation. Data were also analyzed according to a self-system theoretical framework of expectancy-value theory, self-determination theory, attribution theory, and goal orientation. Evidence from the data suggests an increase in cognitive and metacognitive processes that characterize self-regulated learning. Musicians also indicate an increase in motivation to engage in practicing as well as greater self-efficacy in addressing musical challenges. Effective pedagogical approaches for guided practice are discussed as are implications for music education. Suggestions are made for further research.
Stably Non-stable C*-algebras with no Bounded Trace
Keywords: Operator algebras
C*-algebra
Classification
Traces

A well-known theorem of Blackadar and Handelman states that every unital stably finite C*-algebra has a bounded quasitrace. Rather strong generalizations of stable finiteness to the non-unital case can be obtained by either requiring the multiplier algebra to be stably finite, or alternatively requiring it to be at least stably not properly infinite. My thesis deals with the question whether the Blackadar-Handelman result can be extended to the non-unital case with respect to these generalizations of stable finiteness. For suitably well-behaved C*-algebras there is a positive result, but none of the non-unital versions holds in full generality. Two examples of C*-algebras are constructed. The first one is a non-unital, stably commutative C*-algebra A that contradicts the weakest possible generalization of the Blackadar-Handelman theorem: The multiplier algebras of all matrix algebras over A are finite, while A has no bounded quasitrace. The second example is a non-unital, simple C*-algebra B that is stably non-stable, i.e. no matrix algebra over B is a stable C*-algebra. In fact, the multiplier algebras over all matrix algebras of this C*-algebra are not properly infinite. Moreover, the C*-algebra B has no bounded quasitrace and therefore gives a simple counterexample to a possible generalization of the Blackadar-Handelman theorem.
Protein Recovery from Secondary Paper Sludge and Its Potential Use as Wood Adhesive
Keywords: Recycling
Secondary sludge
Protein recovery
Residual biomass
Biorefinery
Adhesion mechanism

Secondary sludge is an essential part of biosolids produced through the waste treatment plant of paper mills. Globally paper mills generate around 3.0 million ton of biosolids and in the absence of beneficial applications, the handling and disposal of this residual biomass poses a serious environmental and economic proposition. Secondary paper sludges were investigated in this work for recovery of proteins and their use as wood adhesive. After identifying extracellular polymeric substances as adhesion pre-cursors through analytical techniques, studies were carried out to optimize protein recovery from SS and its comprehensive characterization. A modified physicochemical protocol was developed to recover protein from secondary sludge in substantial quantities. The combined effect of French press and sonication techniques followed by alkali treatment resulted in significant improvement of 44% in the yield of solubilized protein compared to chemical methods. The characterization studies confirmed the presence of common amino acids in recovered sludge protein in significant quantities and heavy metal concentration was reduced after recovery process. The sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis revealed the presence of both low and high molecular weight protein fractions in recovered sludge protein. After establishing the proof-of-concept in the use of recovered sludge protein as wood adhesive, the bonding mechanism of protein adhesives with cellulose substrate was further elucidated in a complementary protein-modification study involving soy protein isolate and its glycinin fractions. The results of this study validated the prevailing bonding theories by proving that surface wetting, protein structure, and type of wood play important role in determining final adhesive strength. Recovered sludge protein was also investigated for its compatibility to formulate hybrid adhesive blends with formaldehyde and bio-based polymers. Apart from chemical cross-linking, the synergy of adhesive blends was evaluated through classical rule-of-mixture. The findings of this study warrants further investigation concerning other potential uses of recovered sludge protein, especially as food supplements and economic implications.
Modelling the Effects of Seston Food Quality on Zooplankton Growth: Implications for Broader food Web Dynamics
Keywords: Phytoplankton
Zooplankton
food web ecology
food quality
highly unsaturated fatty acids
stoichiometry
mathematical modelling
bifurcation analysis

An increasing number of contemporary studies in aquatic ecology emphasize the im- portance of highly unsaturated fatty acids (HUFAs) at the plant-animal interface. Studies have demonstrated a wide range of fatty acid profiles in primary producers, forcing her- bivorous zooplankton to differentially retain fatty acids to meet somatic requirements. Herbivores also vary in their somatic fatty acid profiles; cladocerans collect Eicosapen- taenoic Acid (EPA), copepods prefer Docosahexaenoic Acid (DHA). Fatty acid internal reserves can be broken down to meet structural needs (i.e. phospholipid synthesis), fuel reproduction and may play a role in cold weather adaptation. Several authors have noted increases in HUFA concentration with lowering ambient temperatures. Cladoceran membranes form a gel at lower temperatures, while copepod membranes remain fluid and allow active overwintering. Both fish and crustaceans accumulate high concentrations of HUFAs during periods of rapid growth, but colimitation with elemental resources may exist. Recent modeling results suggest food webs with high quality (nutritional and biochemical) primary producers can attain inverted biomass distributions with efficient energy transfer between trophic levels. The adoption rate for this material into man- agement studies remains low, and while other sectors of the scientific community thrive on the potential of HUFAs, planktonic food-web studies are choosing traditional view points over forward thinking. Bearing in mind the emerging hypotheses on the critical factors that drive the energy flow in the plant-animal interface, my dissertation will at- tempt to address the following general questions: What are the distinct signatures of food quality and food quantity on planktonic food web dynamics? How do nutritional and biochemical factors affect the flow of energy at the plant-animal interface? What is our current understanding of the role of highly unsaturated fatty acids (HUFAs) in aquatic food webs? To what extent can the current generation of plankton models reproduce the lower food web patterns when explicitly accounting for HUFAs? Is the integration of the HUFA role into water quality management models feasible? Explicitly accounting for HUFAs requires integrating factors of animal physiology with macro-ecology: what are the ramifications? Finally, what are the evolutionary aspects of animals coping with food quality?
Iron Particle Attachment onto Model Geological Substrates
Keywords: iron
attachment

Fresh and aged iron particle attachment onto model mineral surfaces was studied using atomic force microscopy based – force spectroscopy (AFM) in different water chemistries as well as in the presence of surface modifiers for the particles (carboxymethyl cellulose polymer). The forces of interactions measured with AFM were explained in terms of classical DLVO forces (electrostatic, Born and van der Waals forces) as well as hydration, steric and magnetic forces, which are not accounted for by classical models. Theoretical interpretation of the results was thus performed using extended models, in which such interactions were considered. In the absence of surface modifiers, iron particle attachment onto silicates and iron oxides appeared favorable in pure water and salt solutions at pH 4 and 5.5, but was hindered in water amended with humic acids. Attachment of bare CIP was also unfavourable at pH 8, except in the presence of CaCl2 salt at 100 mM concentrations. Attachment between iron particles and iron oxides was favorable even in the presence of polymeric coatings. Conversely, in all solutions such coatings contributed to electro-steric repulsion between particles and silicates, which dominated over attractive van der Waals forces, albeit to a lesser extent in the presence of salts. To best assess the role of polymeric coatings in particle attachment, polymer sorption onto the model mineral surfaces considered was investigated using a Quartz Crystal Microbalance with Dissipation Monitoring. The results obtained confirmed the AFM findings, and furnished insights regarding the role of salts on polymer sorption onto substrates. Finally, the effect of aging on attachment was probed both by AFM and by analyzing cementation phenomena of iron aggregates using scanning electron microscopy, as well as by probing changes in particle compositional properties with various spectroscopy tools. The major effect of aging was to promote the formation of large cemented aggregates, which did not appear prone to disruption or remobilization.
Surviving War: The Congolese Refugee Experience
Keywords: trauma
war trauma
war trauma recovery
surviving war
PTSD
DRC
Constructivist Grounded Theory
refugees
staged model of surviving war
psychological toll of war
war survivors
agency
fortitude
serendipity
dissociation
using interpreters in research
theoretical model of surviving war

A qualitative approach was taken to explore Canadian Congolese refugees’ experience of war trauma recovery. Six volunteers (three men and three women), who self-identified as traumatized by their experience of war in Congo and had lived in Canada for less than ten years, participated in in-depth interviews. Using a constructivist grounded theory approach to analysis, a core construct of Surviving War was identified. A hierarchical model of surviving war was developed that subsumed all other categories. By extrapolating principles from this model, a theory of Surviving War was developed which identifies factors that contribute to surviving war. Limitations of the current research are presented along with suggestions for further research. Recommendations for professionals working with a refugee population are also presented.
Continuity and Renewal in English Homiletic Eschatology, ca. 1150–1200
Keywords: Old English
homilies
Middle English
sermons

This study examines English eschatological homilies of the later twelfth century and their adaptation of both Anglo-Saxon traditions and sources introduced after the Norman Conquest. Later and non-homiletic texts are also discussed when these give clues to the continued prevalence of Anglo-Saxon and twelfth-century eschatological traditions in the later Middle Ages. Chapter 1 introduces the eschatology of the Anglo-Saxon homilists, describes English homily manuscripts written ca. 1150–1200, summarizes scholarly opinions on these texts, and details the author’s approach to the texts’ eschatological ideas. Chapter 2 examines the ‘Visit to the Tomb’ motif, which deeply influenced Anglo-Saxon depictions of individual mortality. Two early Middle English texts––Lambeth III and a treatise on the vices and virtues––contain versions of the motif that indicate a familiarity with the earlier homilies, though they also adapt the ‘Visit to the Tomb’ in new ways. The Old English texts in British Library, Cotton Vespasian D. xiv are the focus of Chapter 3. These include a description of the coming of Antichrist, the first English text of the ‘Fifteen Signs before Doomsday,’ and a typological interpretation of the Babylonian captivity. These pieces draw on both the Old English homilists and works unknown in England until ca. 1100, suggesting that twelfth-century English homilists did not sense any tension in combining ideas from pre- and post-Conquest traditions. Chapter 4 describes the Middle English reflexes of two Doomsday motifs common in the Old English homilies––the ‘Three Hosts of Doomsday’ and the ‘Four Angels of Judgment.’ The persistence of such motifs in later medieval England raises the possibility of a significant influence of Old English works on Middle English homiletic eschatology. The Conclusions section addresses this issue in further detail and suggests avenues of future research, while restating the importance of the twelfth-century homilies for the study of medieval English religious literature.
Working Together across Primary Care, Mental Health & Addictions: Exploring the Association between the Formalization of Organizational Partnerships & Collaboration among Staff Members
Keywords: Inter-organizational partnerships
Formalization
Interprofessional
Collaboration
Service integration
Mental health
Addictions
Primary care

The purpose of this study was to explore the relationship between the formalization of inter-organizational partnerships and collaboration among staff members working together across primary care, mental health and addition organizations to provide services to adults with complex mental health and addiction needs. Phase I of the study provided an environmental scan of existing partnerships among Family Health Teams (FHTs) and Community Health Centres (CHCs), and the Mental Health and/or Addiction (MHA) organizations they partner with, in the province of Ontario (Canada). Phase II explored the relationship between formalization and a) administrative collaboration and b) and service delivery collaboration. The hypotheses proposed that staff members who are part of formalized partnerships would report higher levels of collaboration. Phase III explored how formal and informal partnerships and collaboration are experienced by the administrative and service provider staff members who work across FHTs, CHCs and MHAs organizations. Using a mixed methods approach, data were collected using electronic surveys and telephone interviews. The results of Phase I indicated that FHTs and CHCs in Ontario have between 1-3 partnerships with MHA organizations. Most are informal partnerships, have existed for less than 5 years, and most staff members (partners) interact on a monthly basis. The quantitative results of Phase II showed no significant relationship between formalization and either form of collaboration. The qualitative findings from Phase III provide two key contributions. First, the results of the interviews may help explain why collaboration was not higher in formalized partnerships, as demonstrated by the range of advantages and disadvantages experienced by administrators and service providers in both formal and informal partnerships. Second, the findings illuminate factors related to the process of creating and/or formalizing partnerships, suggesting that there may be other factors that mediate or have a direct impact on the relationship between formalization and collaboration. By bringing together the study findings, the study addresses a gap in the literature by proposing a pathway through which formalization may be associated with collaboration. The results of the study provide opportunities for future research to help improve the quality and accessibility of services to adults with complex mental health and addiction needs.
Nanoscale Chemical Imaging of Synthetic and Biological Materials using Apertureless Near-field Scanning Infrared Microscopy
Keywords: near-field microscopy
polymer
amyloid fibril
nano

Apertureless near-field scanning infrared microscopy is a technique in which an impinging infrared beam is scattered by a sharp atomic force microscopy (AFM) tip oscillating at the resonant frequency of the cantilever in close proximity to a sample. Several advantages offered by near-field imaging include nanoscale imaging with high spatial resolution (near-field imaging is not restricted by the diffraction limit of light) and the ability to differentiate between chemical properties of distinct compounds present in the sample under study due to differences in the scattered field. An overview of the assembly, tuning, and implementation of the near-field instrumentation is provided, as well as detailed descriptions about the samples probed and other instrumentation used. A description of the near-field phenomena, a comparison between aperture and apertureless-type near-field microscopy, and the coupled dipoles model explaining the origin of the chemical contrast present in near-field infrared imaging was discussed. Simultaneous topographic and chemical contrast images were collected at different wavelengths for the block copolymer thin film, polystyrene-b-poly(methyl ethacrylate) (PS-b-PMMA) and for amyloid fibrils synthesized from the #21-31 peptide of β2-microglobulin. In both cases it was observed that the experimental scattered field spectrum correlates strongly with that calculated using the far-field absorption spectrum, and using near-field microscopy, nanoscale structural and/or compositional variations were observed, which would not have been possible using ensemble FTIR measurements. Lastly, tip-enhanced Raman spectra of the #21-31 and #16-22 peptide fragments from the β2-microglobulin and Aβ(1-40) peptide were collected, examined, and an outline of the optimization conditions described.
Asymptotic Analysis of Some Stochastic Models from Population Dynamics and Population Genetics
Keywords: Stochastic processes
Population genetics
Population dynamics
Applied probability

Near the beginning of the last century, R. A. Fisher and Sewall Wright devised an elegant, mathematically tractable model of gene reproduction and replacement that laid the foundation for contemporary population genetics. The Wright-Fisher model and its extensions have given biologists powerful tools of statistical inference that enabled the quantification of genetic drift and selection. Given the utility of these tools, we often forget that their model - for reasons of mathematical tractability - makes assumptions that are violated in many real-world populations. In particular, the classical models assume fixed population sizes, held constant by (unspecified) sampling mechanisms. Here, we consider an alternative framework that merges Moran’s continuous time Markov chain model of allele frequencies in haploid populations of fixed size with the density dependent models of ecological competition of Lotka, Volterra, Gause, and Kolmogorov. This allows for haploid populations of stochastically varying – but bounded – size. Populations are kept finite by resource limitation. We show the existence of limits that naturally generalize the weak and strong selection regimes of classical population genetics, which allow the calculation of fixation times and probabilities, as well as the long-term stationary allele frequency distribution.