VictorJuiz/thesis huggingface dataset:
Exploring De-alloying in Fe-Ni-Cr Alloys and its Relationship to Stress Corrosion Cracking in Nuclear High Temperature Water Environments

Most stress corrosion cracking (SCC) mechanisms initiate from localised corrosion (pitting, intergranular attack, de-alloying), which provides local stress concentration. Alloys are generally more susceptible to SCC than pure metals because selective dissolution or oxidation is possible. De-alloying involves the selective dissolution of the less noble (LN) component from an alloy. The more noble (MN) component enriches on the surface forming a brittle, metallic, nanoporous layer. In noble metal alloys and brass, SCC shows correlation with the threshold LN content below which de-alloying stops (the parting limit). In Fe-Ni-Cr engineering alloys de-alloying may be responsible for Cl-SCC, although this has not been proven explicitly. Initial indications show that de-alloying causes SCC in hot, caustic environments. In some cases, Ni enrichment and porosity are associated with cracks in stainless steel after long-term service in nuclear high temperature water environments, but it is unclear if this plays a causal role in cracking. Here the de-alloying mechanism (primarily the effect of Ni (MN) content) and its relationship to SCC in Fe-Ni-Cr materials (Fe10Ni, 310SS and Alloy 800) is examined using a hot caustic environment, and compared to classical de-alloying systems. De-alloyed layers formed on all materials, although Alloy 800 required a higher temperature. Increasing Ni content improved de-alloying resistance according to classical theory. Unlike classical systems, de-alloying occurred with concurrent MN dissolution and, at open circuit potential (OCP), the layers retained significant Fe and Cr (LN) instead of being ‘almost pure’ MN. Layers formed with applied anodic potential were friable and highly LN depleted. This behaviour was successfully modelled in Kinetic Monte Carlo simulations. Recently, it has been shown that SCC in noble element alloys depends on the mechanical integrity (quality) of the de-alloyed layer; a finding that was reflected here. At 140 °C at OCP the layer on 310SS was too thin to promote SCC and Alloy 800 did not de-alloy significantly. Layers formed with anodic potential did not result in SCC. In 50% NaOH at 280 °C, severely stressed 310SS cracked where thick de-alloyed layers formed. However, the thin layer formed on Alloy 800 was associated with SCC, even with low residual stress.

Keywords: Stress corrosion cracking
Advisor: Newman, Roger C.
Exploring the Impact of Ongoing Colonial Violence on Aboriginal Students in the Postsecondary Classroom

Framed within an Anishnaabe method and an anti-colonial discursive framework, this thesis explores how Aboriginal students confront narratives of colonial violence in the postsecondary classroom while at the same time living and experiencing colonial violence on a daily basis. In order to garner an understanding of what pedagogies might be useful in postsecondary classrooms that cover such curricula, I explored these questions by interviewing 8 Aboriginal students and 5 Aboriginal professors who were taking or teaching courses on Aboriginal peoples and colonial history. I also engaged two Aboriginal Elders in conversations on pedagogy because they are recognized as carriers of Aboriginal traditional knowledge. Drawing on the literature I theorize colonization as violent, ongoing and traumatic. Specifically, I trace how education for Aboriginal peoples has always been and continues to be part of the colonial regime—one that is marked by violence, abuse and a regime that has had devastating consequences for Aboriginal peoples. This thesis confirms that despite some changes to the educational system Aboriginal students and professors interviewed in this research still confront significant challenges when they enter sites such as the postsecondary classroom. The most profound finding in this thesis was the extent of racism that Aboriginal students confront and negotiate in postsecondary classrooms. These negotiations are especially profound and painful in mixed classrooms where the narrative of ongoing colonial violence is discussed. Aboriginal students also employ a number of strategies to resist ongoing colonialism and racism. The narrative of racism is not new but it does reaffirm that colonialism continues to have devastating effects on Aboriginal peoples. It also reaffirms the pervasiveness of violence in our society despite the fact that many would rather ignore or downplay the level of violence that exists. There is no doubt that the Aboriginal students interviewed in this research describe a significant psychological toll in an environment of ongoing colonialism and is especially difficult when revisiting historical and ongoing accounts of violence of their own colonial history. The thesis offers some suggestions for mitigating this impact in the classroom.

Keywords: Aboriginal education
Colonial Violence
Aboriginal pedagogy
Indigenous education
Racism and education
Racism and Aboriginal students
Advisor: Razack, Sherene
Get a Room: Private Space and Private People in Old French and Middle English Love Stories

This study explores the way in which one circumstance of daily life in the twelfth to fourteenth centuries—the relative scarcity of private space—influenced the literature of courtly love. It presents the argument that because access to spatial privacy was difficult, although desirable, stories of illicit love affairs carried on under these precarious circumstances had a special appeal. In these narratives we can observe a tendency for emotional privacy to be invested in trusted confidants and servants, and for spies and meddling figures to pose a special danger. Both of these character types are frequently shown to have privileged access to private space as well as to private knowledge. The framework for this study is provided by a discussion of the material background to developing ideas of privacy, which argues for a greater resemblance between medieval and modern concepts in this area than has previously been acknowledged. The remainder of the study is concerned with literary examples. Medieval French adaptations of the Ars Amatoria show subtle changes in emphasis which can be attributed to the different status of privacy in the medieval world as compared to Augustan Rome. The Lais of Marie de France, in particular Guigemar, Yonec, Milun, Eliduc and Lanval, are discussed in relation to the concept of the female household, a specific category of private space within the medieval castle. Three of the romances of Chrétien de Troyes—Cligès, Lancelot and Yvain—present significant variations on the theme of love mediated by third parties and flourishing in private space. Five different versions of the Tristan and Isolt story are discussed, showing their consistent preoccupation with the roles played by helping and hindering figures. The study concludes with a consideration of three works by Chaucer. Troilus and Criseyde gives prominent place to the most fully developed example of a character who mediates between lovers, Criseyde’s notorious uncle Pandarus, while The Miller’s Tale and The Merchant’s Tale both centre on lovers’ quests for privacy, but do so to mock rather than to celebrate the conventions of courtly love.

Keywords: Old French
Middle English
privacy
poetry
Advisor: Akbari, Suzanne Conklin
Government Relations in the Post-secondary Education Sector in Ontario

There has been little research on the government relations function within the post-secondary education sector in Ontario. This study explores this topic by reviewing the literature and collecting data from key informants in the college, university and government sector, and those who can speak about the sector associations. The study describes how the leaders of colleges and universities in Ontario perceive and conduct government relations, both as individual institutions and as a sector, and analyzes trends and potential implications. The study utilizes a pluralist model of interest group behaviour and applied the hollow-core theory to the policy community and the findings provide compelling evidence that this theory is a useful theoretical framework for understanding the nature of this policy community. This study also provides valuable insight into the hollow-core theory of pluralism. The leadership of individual colleges and universities shares a similar understanding of government relations and engage a similar approach. Individual colleges and universities work independently to lobby for capital funding and work together through their respective associations to lobby for system-wide funding and reforms. Although the presidents of individual institutions continue to lead the government relations function, the trend in the post-secondary education sector in Ontario is to invest additional resources and time in these activities. This study is the first of its kind in Ontario and makes an important contribution to our understanding of the way leaders in the post-secondary education sector in Ontario perceive and conduct government relations. Implications of the findings are considered and recommendations are made for further research.

Keywords: Government relations
lobbying
post-secondary education in Ontario
college-government relations
university-government relations
interest groups in higher education
policy communities in higher education
Advisor: Jones, Glen A.
Interactive Visualizations of Natural Language

While linguistic skill is a hallmark of humanity, the increasing volume of linguistic data each of us faces is causing individual and societal problems — ‘information overload’ is a commonly discussed condition. Tasks such as finding the most appropriate information online, understanding the contents of a personal email repository, and translating documents from another language are now commonplace. These tasks need not cause stress and feelings of overload: the human intellectual capacity is not the problem. Rather, the computational interfaces to linguistic data are problematic — there exists a Linguistic Visualization Divide in the current state-of-the-art. Through five design studies, this dissertation combines sophisticated natural language processing algorithms with information visualization techniques grounded in evidence of human visuospatial capabilities. The first design study, Uncertainty Lattices, augments real-time computermediated communication, such as cross-language instant messaging chat and automatic speech recognition. By providing explicit indications of algorithmic confidence, the visualization enables informed decisions about the quality of computational outputs. Two design studies explore the space of content analysis. DocuBurst is an interactive visualization of document content, which spatially organizes words using an expert-created ontology. Broadening from single documents to document collections, Parallel Tag Clouds combine keyword extraction and coordinated visualizations to provide comparative overviews across subsets of a faceted text corpus. Finally, two studies address visualization for natural language processing research. The Bubble Sets visualization draws secondary set relations around arbitrary collections of items, such as a linguistic parse tree. From this design study we propose a theory of spatial rights to consider when assigning visual encodings to data. Expanding considerations of spatial rights, we present a formalism to organize the variety of approaches to coordinated and linked visualization, and introduce VisLink, a new method to relate and explore multiple 2d visualizations in 3d space. Intervisualization connections allow for cross-visualization queries and support high level comparison between visualizations. From the design studies we distill challenges common to visualizing language data, including maintaining legibility, supporting detailed reading, addressing data scale challenges, and managing problems arising from semantic ambiguity.

Keywords: visualization
linguistics
natural language processing
information visualization
machine translation
Advisor: Penn, Gerald
Carpendale, Sheelagh
Evolution of Local Adaptation During Plant Invasion: Purple Loosestrife (Lythrum salicaria – Lythraceae) in Eastern North America

Biological invasions provide opportunities to study evolutionary processes occurring during contemporary time scales. Here, I combine a literature review of common garden studies of invasive plant species, with field and glasshouse experiments on populations of the outcrossing, perennial, wetland invader Lythrum salicaria (purple loosestrife - Lythraceae), to investigate the evolutionary genetics of local adaptation in reproductive and life-history traits. A review of 32 common garden studies of 28 introduced species identified previously unrecognized latitudinal clines in phenotypic traits in both native and introduced populations. To obtain direct evidence for clinal variation and local adaptation, I investigated populations of L. salicaria sampled along a latitudinal gradient of growing season length in eastern North America. Controlled pollinations of plants from 12 populations provided no evidence for the breakdown of self-incompatibility to self-compatibility towards the northern range limit. However, a quantitative genetic experiment involving 20 populations revealed latitudinal clines in population mean, variance and skew for days to flower and vegetative size. Broad-sense estimates of genetic variance were significant for most traits; however, strong inter-correlations among traits suggested that fitness trade-offs have constrained population divergence. The observed clines supported a model of selection for early flowering in northern populations constrained by a trade-off between age and size at flowering. A comparison of variance-covariance matrices of family and population means (G and D, respectively) of life-history traits demonstrated that populations have evolved in response to selection under genetic constraints, rather than through neutral processes. A reciprocal transplant experiment involving six populations and three common gardens spanning the latitudinal range provided direct evidence for local adaptation in flowering phenology. Populations maintained the same rank-order for time to flowering and vegetative size at each site, and southern populations had the highest fecundity at the southern site but the lowest at the northern site. Finally, a phenotypic selection analysis in each common garden involving 61 F2 families of crosses between a northern × southern populations confirmed that selection favours earlier flowering in northern populations. These results demonstrate that natural selection on reproductive phenology has accompanied the invasive spread of L. salicaria in eastern N. America.

Keywords: Lythrum salicaria
quantitative genetics
evolution
range limits
genetic constraints
invasive species
Advisor: Barrett, Spencer C. H.
Minoritized Parents, Special Education, and Inclusion

While there is a large body of literature on the subject of inclusion from a student’s perspective in terms of program delivery, little has been written about how minoritized parents are included in special education processes. This critical study examines how minoritized parents – those who are at times disadvantaged because of how they are differentiated within society – are included in and/or excluded from special education in the varying circumstances associated with this process. To delve into the parameters and implementation of special education identification, placement, and program delivery, I spoke with four minoritized parents and one minoritized youth engagement worker. Additionally, I examined codified policies and regulations, in order to consider how individuals interpret and shape the enactment of this policy within school cultures. In recording and coding the stories of minoritized parents, I have found that Ontario’s system of identification, placement, and program delivery presently leads minoritized parents to experience varying degrees of inclusion and/or exclusion. These degrees may be influenced by a number of circumstances, including how knowledge, language, positioning, and philosophy are presented. As outlined in this paper, Ontario’s Ministry of Education, along with school boards across the province, may pursue a number of different change avenues, and these paths will inevitably lead to different outcomes. While some paths may lead to conflict resolution and enriched inclusion, others may intensify situations of exclusion. Any sort of policy change that sets out to transform special education identification, placement, and program delivery along an Inclusion/Exclusion, Transparency/Opaqueness continuum would ultimately have to address a variety of complications. While the two general forces of larger social context and policy complications are addressed in the concluding chapter of the paper, the specific manner in which they materialize cannot be predicted with complete accuracy. Rather than articulating a detailed set of instructions to redesign policy, I hope to generate critical reflection and discussion on the matter of transforming Ontario’s special education model. If special education inclusion is to be enriched in Ontario, change is imperative.

Keywords: special education
inclusion
minoritization
Advisor: Ryan, James
DNA Replication and Trinucleotide Repeat Instability in Myotonic Dystrophy Type 1

The expansion of gene-specific trinucleotide repeats is responsible for a growing list of human disorders, including myotonic dystrophy type 1 (DM1). Repeat instability for most of these disorders, including DM1, is characterized by complex patterns of inherited and ongoing tissue-specific instability and pathogenesis. While the mechanistic basis behind the unique locus-specific instability of trinucleotide repeats is currently unknown, DNA metabolic processes are likely to play a role. My thesis involves investigating the contribution of DNA replication to the trinucleotide instability of myotonic dystrophy type 1. Herein I have designed an in vivo primate model system, based on the SV40 replication system, to assess the contribution of DNA replication to DM1 repeat instability. This system allows the assessment, under controlled conditions, and manipulation of variables that may affect replication-associated repeat instability, under a primate cellular system. Using the SV40 model system, I not only confirmed previous observations that repeat length and replication direction affect repeat instability, but also for the first time determined that the location of the replication origin relative to the repeat tract plays an important role in repeat instability. This novel observation allowed for the development of a fork-shift model of repeat instability, in which cis-elements adjacent to the repeat tract affect replication, in turn altering the propensity for repeat instability. To further my study of DNA replication in DM1 repeat instability, I have mapped the origin of replication adjacent to the DM1 locus in human patient cells and the tissues of DM1 transgenic mice actively undergoing repeat instability. The position of the replication origins adjacent to the repeat tract at the DM1 locus places several known cis-elements, including CTCF binding sites, in a position to alter replication as predicted by the fork-shift model. My analysis of the CTCF sites showed them capable of altering replication and repeat instability at the DM1 locus. Taken together these results suggest that the placement of replication origins, repeat tracts and cis-elements, may mark trinucleotide repeat tracts, such as the DM1, for locus-, tissue- and development-specific replication-associated repeat instability.

Keywords: DNA replication
neurodegeneration
triplet repeat
cis-element
instability
model system
Advisor: Pearson, Christopher E.
Real and Complex Dynamics of Unicritical Maps

In this thesis, we prove two results. The first concerns the dynamics of typical maps in families of higher degree unimodal maps, and the second concerns the Hausdorff dimension of the Julia sets of certain quadratic maps. In the first part, we construct a lamination of the space of unimodal maps whose critical points have fixed degree d greater than or equal to 2 by the hybrid classes. As in [ALM], we show that the hybrid classes laminate neighbourhoods of all but countably many maps in the families under consideration. The structure of the lamination yields a partition of the parameter space for one-parameter real analytic families of unimodal maps of degree d and allows us to transfer a priori bounds from the phase space to the parameter space. This result implies that the statistical description of typical unimodal maps obtained in [ALM], [AM3] and [AM4] also holds in families of higher degree unimodal maps, in particular, almost every map in such a family is either regular or stochastic. In the second part, we prove the Poincare exponent for the Fibonacci map is less than two, which implies that the Hausdor ff dimension of its Julia set is less than two.

Keywords: holomorphic dynamics
Advisor: Lyubich, Mikhail
Rewriting Marpole: The Path to Cultural Complexity in the Gulf of Georgia.

This dissertation examines prehistoric culture change in the Gulf of Georgia region of the Northwest Coast of North America during the Locarno Beach (3500 – 1100 BP) and Marpole (2000 – 1100 BP) periods. The Marpole culture has traditionally been seen to possess all the traits associated with complex hunter-gatherers on the Northwest Coast (hereditary inequality, multi-family housing, storage-based economies, resource ownership, wealth accumulation, etc.) while the Locarno Beach culture has not. This research examined artifact and faunal assemblages as well as data for art and mortuary architecture from a total of 164 Gulf of Georgia archaeological site components. Geographic location and ethnographic language distribution were also compared to the archaeological data. Analysis was undertaken using Integrative Distance Analysis (IDA), a new statistical methodology developed in the course of this research. Results indicated that Marpole culture was not a regional phenomenon but rather was much more spatially and temporally discrete than previously known. Artifactual assemblages identified as Marpole were restricted to the areas of the Fraser River, northern Gulf Islands and portions of Vancouver Island, an area contiguous with both Mitchell’s (1971b) “Fraser River Fishermen” economic sub-area and the ethnographic territory of the Downriver and Island Halkomelem peoples. In contrast, the geographic area of Mitchell’s (1971b) “Straits Reef-net Fishermen”, the ethnographic territory of the Straits Salish, showed no sign of Marpole culture but rather a presence of Late Locarno Beach culture. The pattern found in artifacts was replicated in the distribution of art and mortuary architecture variation suggesting the cultural differences between Marpole and Late Locarno Beach cultures was real and not a statistical anomaly. The matching distribution of prehistoric cultural variability and the ethnographic pattern of language groups indicate a long standing and stable cultural dynamic within the Gulf of Georgia.

Keywords: Northwest Coast
Archaeology
Marpole
IDA
Advisor: Coupland, Gary