VictorJuiz/thesis huggingface dataset:
Methods and Motion in Paediatric fMRI

Functional magnetic resonance imaging (fMRI) enables non-invasive investigation of the neural functions with excellent spatial resolution. Although fMRI has primarily been developed in young adult populations, its use is becoming widespread in paediatrics. However, there are many differences, both behavioural and physical, between adults and children requiring adjustments to imaging and analysis methodology to optimise the results in children. This thesis examines fMRI analysis methodology to improve the detection of developmental changes in the brain. The work uses an emotional and familiar face paradigm that elicits strong BOLD fMRI responses in the fusiform, a region that is still developing across childhood. This face paradigm also enables the comparison of the fusiform responses to the primary visual cortex to link to extensive results in the literature. Thirty five 4-8 year old children and fourteen adults (18-30 years old) were scanned. To address the concern of anatomical size differences between the brains of adults and children, the anatomical variability of the fusiform was measured and the validity of stereotaxic transformation into an adult template was confirmed for the children. To investigate the effect of threshold settings between the adults and children, individual subject analyses of the peak activation location, estimated signal percent change and noise values were calculated using the general linear model (GLM). Similar functional peak locations between individuals were quantitatively selected using a novel application of the activation likelihood estimation (ALE). Also, several different preprocessing steps were evaluated for their ability to correct for the increased motion frequently seen in children, in a quantitative framework (NPAIRS) using canonical variates analysis (CVA), a data driven multivariate model as well as the standard univariate GLM. Functional differences between the adults and the children were identified in the fusiform by applying these optimised procedures. The results of this thesis demonstrate that thresholding and preprocessing pipelines must be made in a group-specific fashion. These methods can also be extended to elderly populations, enabling the investigation of the complete ageing spectrum with fMRI.

Keywords: functional magnetic resonance imaging
methodology
brain development
paediatric
Advisor: Taylor, Margot
Strother, Stephen
Modelling the Mind: Conceptual Blending and Modernist Narratives

This thesis offers a new approach to mind modelling in modernist narratives. Taking Nietzsche’s work as exemplary of modernist ideas about cognition’s relational basis, I argue that conceptual blending theory, a particularly cogent model of a fundamental cognitive process, has roots in modernism. I read inscriptions of relational cognition in modernist narratives as “conceptual blends” that invite cognitive mobility as a central facet of reader response. These blends, which integrate conceptual domains, invite similarity-seeing and difference-seeing, exposing the reader to new conceptual content and new cognitive styles; she is thus better able to negotiate the reading-related complexities of modernist narrative’s formal innovations and the real-world complexities of modernity’s local and global upheavals. Chapter One considers blending’s interrelated rhetorical motivations and cognitive effects in Chiang Yee’s Silent Traveller narratives: bringing together English and Chinese domains, Chiang’s blends defamiliarize his readers’ culturally entrenched assumptions, invite collaborative reading strategies, and thus equip his readers for relating flexibly to a newly globalized world. Moving away from blends in a text’s narration, Chapter Two focuses on blends as textual structuring principles. I read Virginia Woolf’s The Waves as a thinking mind with fundamentally relational cognitive processes; I consider the mobile cognitive operations we perform reading about a text’s mind thinking and thinking along with it. Chapters Three and Four cross the nebulous text-peritext border to examine blends in modernist prefaces. Chapter Three focuses on blends in Joseph Conrad’s and Henry James’s prefaces, relating them, through the reading strategies they invite, to the narratives they accompany. Chapter Four considers allographic prefaces to Arthur Morrison’s Tales of Mean Streets and two of Chiang’s narratives: blends in these prefaces invite the cognitive mobility necessary for reconceptualizing both allographic preface-text and East-West relations. All four chapters treat the modernist narrative text as a textual system whose blends, often interacting and borderless, signal reciprocal, mutually permeable relations among its textual levels. Dialogic relations also underwrite the interaction between these blends and blends the reader performs when engaging with them. Modernist narratives model (bear inscriptions of) cognition’s relational processes in order to model (shape) the reader’s mind.

Keywords: Modernist Narratives
Cognitive Approaches
Rhetorical Approaches
Conceptual Blending
Reading
Advisor: Cuddy-Keane, Melba
Modulation of the M2 Muscarinic Cholinergic Receptor by Cholesterol

M2 muscarinic receptor extracted from Sf9 cells in cholate-NaCl differs from that extracted from porcine sarcolemmal membranes. Whereas the latter has been shown to exhibit non-competitive effects in the binding of N-methylscopolamine (NMS) and quinuclidinylbenzilate (QNB), which can be explained in terms of cooperativity within a receptor that is at least tetravalent, binding to the former is essentially competitive. Levels of cholesterol in Sf9 membranes were only 5% of those in sarcolemmal membranes and were increased to about 100% by means of cholesterol-methyl-β-cyclodextrin. M2 receptors extracted from CHL-treated Sf9 membranes resembled those from heart; that is, cholesterol induced a pronounced heterogeneity detected in the binding of both radioligands, including a shortfall in the apparent capacity for [3H]NMS, and there were marked discrepancies in the apparent affinity of NMS as estimated directly and via the inhibition of [3H]QNB. The data can be described quantitatively in terms of cooperative effects among six or more interacting sites, apparently within an oligomer. Cholesterol also was found to increase the affinity of the receptor for NMS and QNB, and the effect was examined for its possible relationship to the known interconversion of cardiac muscarinic receptors between an agonist-specific (R*) and an antagonist-specific (R) state. Cholesterol and N-ethylmaleimide (NEM) were compared for their effect on the affinity of NMS, QNB and four muscarinic agonists, and the data were assessed in terms of an explicit mechanistic model for a receptor that interconverts spontaneously between two states. The data can be described equally well by an effect of cholesterol on either the distribution of receptors between R and R* or the affinity of all ligands for both states, with an accompanying effect of NEM on either the affinity or the distribution between states, respectively. Since NEM is known from other data to favor R* over R, cholesterol appears to increase affinity per se. Cholesterol therefore is a determinant of affinity and cooperativity in the binding of orthosteric ligands to the M2 receptor. Both effects are observed in solution and therefore appear to arise from a direct interaction between the lipid and the receptor.

Keywords: GPCR
Cholesterol
Cooperativity
Muscarinic
Oligomers
Advisor: James, Wells
Compatibility of X-ray Tubes with Magnetic Resonance Imaging Scanners for Aortic Valve Replacement

Aortic stenosis is the most common acquired heart valve condition. Open-heart surgical aortic valve replacement is an effective treatment for patients who receive it. However, approximately one-third of patients who require this treatment do not receive it due to the risks associated with the surgery. Percutaneous aortic valve replacement (PAVR) is a minimally invasive technique that can replace the aortic valve of patients contraindicated for open-heart surgery. Although PAVR is now entering clinical practice, a closed bore hybrid x-ray/MRI (CBXMR) imaging system is under development to improve the safety and efficacy of PAVR. This system will harness the complementary strengths of x-ray imaging (surgical tool/vascular imaging) and MRI (cardiac soft tissue contrast) to deploy a bioprosthesis in the aortic annulus. An x-ray C-arm will be placed about 1 m from the entrance of the MRI scanner to facilitate smooth intermodality patient transfer during the procedure. The performance of a rotating-anode x-ray tube in the magnetic fringe field of a 1.5 T MRI scanner was investigated. A rotating-anode x-ray tube provides the fluoroscopy and angiography needed for PAVR. The magnetic fringe field can affect the ability of the x-ray tube to dissipate heat. It was shown that the fringe field perpendicular to the anode rotation axis can reduce anode rotation frequency. These effects can limit the maximum permissible power that can be safely dissipated on the anode track during a single exposure. In the fringe field strengths at the C-arm position (4-5 mT), anode rotation frequency only decreased by about 1%, which will have negligible impact on tube heat loadability. The fringe field can cause a field of view shift. The field of view shifted by approximately 3 mm, which can be corrected by active magnetic shielding and further collimation. An active magnetic shielding system was constructed that can correct focal spot deflection. These results are facilitating the construction of a prototype CBXMR system, the goal of which is to improve success rates for PAVR procedures.

Keywords: multimodality imaging
percutaneous interventions
x-ray imaging
magnetic fields
x-ray tube
magnetic resonance imaging
aortic valve replacement
interventional cardiology
Advisor: Rowlands, John A.
When Everything Matters: Comparing the Experiences of First Nations and Non-Aboriginal Children Removed from their Families in Nova Scotia from 2003 to 2005

The Canadian Incidence Study on Reported Child Abuse and Neglect (Trocme, 2001) found that structural factors such as poverty, poor housing and substance misuse contribute to the over-representation of First Nations children in child welfare care and yet there is very little information on the experiences of First Nations and Non-Aboriginal children after they are placed in care. The When Everything Matters study tracks First Nations and Non-Aboriginal chlidren removed from their families between 2003-2005 in Nova Scotia to the time of reunification or to the time of data collection if the child remained in care. The characteristics of children and their families are compared to the primary aims of child welfare services provided to children and their families. Results indicate that poor families living in poor housing are graphically over-represented among all families who have their children removed. Poverty-related services were not provided to families in proportion to its occurrence. Caregiver incapacity related to substance misuse was most often cited as the primary reason for removal and although substance misuse services were provided there is a need for further child welfare training, policy and services in this area given the scope of the problem presenting in both First Nations and Non-Aboriginal families. Study findings are nested in a new bi-cultural theoretical framework founded in First Nations ontology and physic's theory of everything called the breath of life theory. Implications for theoretical development as well as child welfare research, policy and practice are discussed.

Keywords: First Nations
Child Welfare
Social Science Theory
Advisor: Regehr, Cheryl
L'Asymétrie entre L'Acquisition des Clitiques Sujets/Objets chez les Enfants francophones et L'Optionalité dans la Grammaire Enfantine

In light of recent theoretical and methodological developments in the areas of French morphosyntax and child acquisition, the present dissertation reconsiders the asymmetry reported in previous studies of the acquisition of subject and object clitics in French-speaking children. Our reanalysis allows us to address two important questions in the domain of acquisition, namely optionality in the child’s grammar and the role of input in development. By means of an exhaustive analysis of child and adult production, our research illustrates that adults produce several subject/object asymmetries, and we propose that the asymmetry reported for children is attributable to properties of the target language and not to the acquisition process. Beyond these conclusions, our research reveals a significant asymmetry during the course of acquisition, namely that the subject clitic reaches the target grammar faster than the object clitic. This asymmetry, which we qualify as rhythmic, is caused by a prolonged optionality of the object clitic. However, our study shows that this optionality is not generalized. Until roughly 3 years of age, object and subject clitics show a parallel development in spontaneous speech: they are optional. After this period (around 3 years), their production reaches the levels observed in adults. In contrast, some studies in elicited production have shown that object clitics are still optional beyond 3 years. These contradictory results lead us to propose that there are two types of optionality: spontaneous and induced. We explore possible sources of these phenomena and propose that the status of pronouns as clitic elements plays a role in spontaneous optionality. As for the induced optionality, we propose that it is attributable to variation in the input and the child’s tendency to regularize it. Overall, our results allow us to redefine the asymmetry, to propose that optionality is a multifactorial phenomenon, and to illustrate the role of input in the optionality exhibited by French children for this domain.

Keywords: first language
acquisition
clitics
French
asymmetry
Advisor: Roberge, Yves
Pirvulescu, Mihaela
Cellular Components of Naturally Varying Behaviours in the Fruit Fly, Drosophila melanogaster

It is now well accepted, through the use of mutational studies, that genes influence behavioural variation. However, we have little knowledge of the cellular and neuronal mechanisms underlying the effects of specific genes. This thesis broadens our understanding of the neurogenetic underpinnings of naturally occurring differences in behaviour using the genetically tractable model organism Drosophila melanogaster. The thesis focuses on allelic variation at the foraging (for) gene which influences both larval and adult behaviour. In particular, for’s cellular/neural contributions to food-related behaviours and learning and memory is investigated. In the first study, we map FOR protein distribution patterns in the adult brain and use this knowledge to demonstrate a neural-specific function for the for gene in adult food-related behaviour. In the second study we demonstrate a novel role for for in the regulation of naturally existing differences in fly learning and memory in the mushroom bodies of the fly brain. In the third study, I explore FOR distribution patterns in larval tissues. I show that FOR is expressed both in neural and non-neural tissues suggesting a distributed function for FOR in food-related behaviours in the larva. In the last study, I describe naturally existing differences in fat metabolism in the Drosophila larva fat storage tissue. FOR is expressed in the fat storage tissue and may regulate lipid packaging, a trait linked to foraging. In general, my thesis is a cellular and neurogenetic analysis of natural variation in behavioural and physiological traits of D. melanogaster. The functions of FOR in food-related behaviours, nutrient physiology and cognition are conserved across taxa. The findings of this thesis should provide a framework to understand these phenomena in a wide range of organisms.

Keywords: Behavior genetics
foraging
PKG
learning and memory
natural variations
lipid metabolism
neurogenetics
Advisor: Sokolowski, Marla B.
The de novo Prediction of Functionally Significant Sequence Motifs in Arabidopsis thaliana.

This thesis performs de novo predictions for functionally significant sequence motifs in the Arabidopsis genome under two separate contexts. Each study applies the use of genomic positional information, statistical over-representation and several biologically contextual filters to maximize the visibility of biological signal in prediction results. Numerous literature supported motifs are prevalent in the results of both studies and a number of novel motif patterns possess a strong potential for in planta significance. The first study examines the statistical over-representation of C-terminal tripeptides as a means for identifying eukaryotic conserved protein targetting signatures. Comparative genomics is applied to the analysis of tripeptide frequencies in the C-terminus of 7 eukaryotic proteomes. While biological signal is maximized through the filtering of both simple sequences and homologous sequences present across protein families. The second study introduces a methodology for the effective prediction of transcription factor binding sites in Arabidopsis. A collection of motif prediction algorithms and a novel enumerative strategy are applied to the prediction of cis-acting regulatory elements within the promoters of genes found coexpressed within distinct tissues and under specific abiotic stress treatments. Overall, the analysis identifies 4 known motifs in expected contexts, 5 known motifs in novel contexts and 7 novel motifs with a high potential for biological function.

Keywords: arabidopsis
transcription
cis elements
regulatory sequences
c-terminus
bioinformatics
genomics
microarray
motif
abiotic stress
tissue-specific
transcription factor binding site
Advisor: Provart, Nicholas
The Role of Type VIII Collagen in Vascular Occlusive Disease

During atherosclerosis and restenosis, there is an extensive amount of collagen synthesis and degradation. Changes in the types of collagen present can have profound effects on vascular smooth muscle cell (SMC) proliferation and migration. Type VIII collagen, which is normally present at low levels within the mature vascular system, is greatly increased during atherogenesis. The central theme of this thesis is to determine the role of type VIII collagen in the pathogenesis of atherosclerosis and restenosis. In the first study, we demonstrated the importance of type VIII collagen in SMC migration and proliferation. SMCs from type VIII collagen-deficient mice display increased adhesion and decreased spreading, migration, and proliferation compared to SMCs from wild-type mice. Treatment of SMCs from type VIII collagen-deficient mice with exogenous type VIII collagen can rescue the defects. In the second study, we determined that type VIII collagen exerts its effects through regulation of MMP-2 expression. Type VIII collagen-deficient SMCs have decreased levels of MMP-2 and are impaired in chemotaxis toward PDGF-BB and in their ability to contract thick collagen gels. We found that decreasing endogenous MMP-2 levels in normal SMCs or adding exogenous collagen to type VIII collagen-deficient SMCs is sufficient to recapitulate the type VIII collagen-deficient or wild-type SMC phenotype, respectively. In the third study, we investigated the contribution of type VIII collagen to intimal hyperplasia after mechanical injury in the mouse. We found that type VIII collagen-deficient mice display a 35% reduction in intimal hyperplasia and attenuated vessel remodeling after femoral artery wire injury, establishing a role for type VIII collagen in restenosis. The results of the work presented in this thesis demonstrate that production of type VIII collagen confers an SMC phenotype with a greater propencity for proliferation and migration. These effects are in part mediated through regulation of MMP-2 expression and activation. We conclude that the increases in type VIII collagen production that occur during atherosclerosis and restenosis contribute to the capacity of SMCs to alter the existing extracellular matrix in a manner which permits enhanced migration.

Keywords: restenosis
atherosclerosis
SMCs
type VIII collagen
migration
Advisor: Bendeck, Michelle
The Idea of Constitutional Rights and the Transformation of Canadian Constitutional Law, 1930-1960

This dissertation argues that the idea of constitutional rights transformed Canadian constitutional law well before the entrenchment of the Canadian Charter of Rights and Freedoms. Specifically, it locates the origins of Canada’s twentieth-century rights revolution in the constitutional thinking of scholars, lawyers, judges, and politicians at mid-century (1930-1960). Drawing on archival documents, personal papers, government reports, parliamentary debates, case law, and legal scholarship, this work traces the constitutional thought and culture that first propelled human rights and fundamental freedoms to the forefront of the Canadian legal imagination. As a work of legal history, it also seeks to revive the dormant spirit of constitutional history that once pervaded the discipline of Canadian constitutional law. The Introduction situates the chapters that follow within the emerging Canadian historiography of rights. Chapter Two traces the origins of Frank Scott’s advocacy for constitutional rights to the newer constitutional law, an approach to constitutional scholarship sparked by the social and political upheavals of the Depression, and the influence of Roscoe Pound’s sociological jurisprudence. Chapter Three explores the varied dimensions of the Second World War’s influence on the nascent idea of Canadian constitutional rights. In particular, the rapid rise of the wartime administrative state produced a rights discourse that tended to reflect the interests of property while ignoring the civil liberties of unpopular minorities. Chapter Four examines the rise of a politics and scholarship of rights in the years immediately following the war. In response to international rights ideals and continuing domestic rights controversies, scholars and lawyers sought to produce a theory of Canadian constitutional law that could accommodate the addition of judicially-enforced individual rights. If not entirely successful, their efforts nonetheless further reoriented the fundamental tenets of Canadian constitutional law. Chapter Five reveals the influence of Canada’s emerging constitutional culture of rights on the jurisprudence of the Supreme Court of Canada, particularly Justice Ivan Rand and his conception of an implied bill of rights. Together, these chapters demonstrate the confluence of ideology, circumstance, and personality – the constitutional history – that altered the future of Canadian constitutional law.

Keywords: Constitutional Law
Legal History
Human Rights
Intellectual History
Advisor: Schneiderman, David