VictorJuiz/thesis huggingface dataset:
Etiologic factors associated with nevus involvement and p53 abnormality in cutaneous malignant melanoma

Tumour characteristics found to be associated with nevus involvement included thin Breslow thickness and superficial spreading histologic subtype. Subjects with many nevi were significantly more likely to have a melanoma with nevus involvement. Two indicators of high cumulative exposure to sunlight (melanoma location on the head and neck, solar elastosis adjacent to the melanoma) were less prevalent among melanomas with no nevus involvement. Factors found to be positively associated with the presence of strong p53 staining (>10% of cells positively stained, vs. tumours with no staining) included thicker Breslow thickness, male sex, having few nevi on the back, no evidence of nevus involvement, and having ever received a blistering sunburn. Melanomas exhibiting strong p53 staining were also positively associated with some indicators of high cumulative sun exposure (lentigo maligna melanoma subtype, melanoma location on the head or neck, evidence of solar elastosis, previous diagnosis of non-melanoma skin cancer). Recent studies have reported different risk factor distributions between subgroups of cutaneous malignant melanoma (CMM) characterized by the presence or absence of tumour markers (nevus involvement, p53 protein abnormality). These findings have led to hypotheses positing the existence of etiologically distinct disease pathways in melanoma tumourigenesis. In order to address the hypothesis of etiologic heterogeneity in melanoma, a case-only analysis was performed to identify etiologic factors associated with evidence of nevus involvement and p53 protein abnormality in CMM. The analysis employed data from Canadian (Ontario, British Columbia) and Australian (New South Wales) subjects with a first primary CMM participating in the International Study of Genes, Environment and Melanoma. Evidence of nevus involvement was assessed for 932 subjects as part of a histopathologic review of diagnostic slides by study pathologists. Immunohistochemical staining using the monoclonal antibody DO-7 was conducted on tumour sections from 523 subjects to assess the presence of p53 protein abnormality. Measures of skin pigmentation phenotype, sun sensitivity and past sun exposure were measured using a self-administered questionnaire and telephone interview. The findings from this analysis offer limited evidence in support of a multiple-pathway model of melanoma pathogenesis; additional research investigating the existence of etiologic heterogeneity in melanoma is warranted.
The role of knowledge building in medical education

This thesis investigated the role of knowledge building pedagogy and technology in medical education. The literature in medical education points to a need for change to better address society's needs for greater community orientation in medicine and integration of new knowledge media. These goals are reflected in the Canadian Medical Education Framework of the Royal College of Physicians and Surgeons. Knowledge Building is an innovative theoretical framework and pedagogy with emphasis on the engagement of all community members in contributing ideas of value to local communities and society, facilitated by Internet-based knowledge building environments. The goal of this research was to determine the applicability and usefulness of knowledge building across various levels in medical education. Case studies were conducted in four University of Toronto contexts: undergraduate Foundations of Medical Practice Course, Obstetrics/Gynecology Graduate Residency Program, Graduate Family Medicine Residency Program, and Psychiatry Continuing Medical Education Course. An online knowledge building environment, Knowledge Forum, supported the knowledge building work which was conducted over a series of investigations lasting 1 to 16 weeks, with the investigations largely conducted as add-ons to course work. Fifty-seven participants (teachers and students) were engaged in these four contexts; 75% volunteered for the add-on component. Thirty-six months after the pilot investigations the four professors were interviewed to assess current practices and beliefs. Analyses focus on barriers and challenges in integrating knowledge building principles and technologies into medical education. Discourse analysis revealed expert-dominated discourse---in many ways right-answer-driven and exam-based, and leaving little room for student contributions, constructive engagement with authoritative sources, or self- and group-assessment. Teacher-generated activities, along with a curriculum with large amounts of prescribed information to be learned, made it difficult for students to find time to work creatively with ideas, consult additional sources, or reflect on diagnoses and prescriptions. The belief that knowledge innovation should occur after the acquisition of foundational knowledge, not in parallel, reflected a tension between espoused ideals and "add-on" status for knowledge building pedagogics and technologies. Results are consistent with the literature on change, suggesting that reform will be slow, but propelled by prevailing expectations of change and new knowledge media.

Keywords: Medicine, Study and teaching
Medicine, Ontario
Physicians, Education
Physicians, Ontario
Of two minds: An exploration of Lord Halifax's road to resistance

This thesis offers a re-evaluation of Lord Halifax's role in the policy of appeasement. As Foreign Secretary to Prime Minister Neville Chamberlain from late February 1938 through the outbreak of the Second World War, Halifax played a pivotal part in the formation and execution of the policies associated with that government. Most studies have assumed that—with the exception of a disagreement that emerged just prior to Munich—Halifax agreed with these policies, and that the disagreement was the result of a “sudden change of heart.” In the following pages, however, it will be shown that Halifax's pre-Munich stance was not the result of such a change, but rather, a reaction that grew out of private set of influencing factors and motivations. These factors will be named, examined and applied not only to Halifax's actions at the time of Munich, but to the entire pre-war period.
The relationships between sibling status, language development, theory of mind, and early reading in preschoolers

Children undergo many changes during the preschool years, especially in terms of cognitive development, for example, language development, theory of mind, and reading. The current study investigates the effect that siblings may have on these areas of early learning. Early learning was measured by standardized and experimental tasks. Based on previous research it was expected that children with siblings would perform better on early learning tasks than children without siblings. In addition, it was predicted that oldest and middle children would outperform youngest children. Surprisingly, it was found that children with siblings did not perform better than children without siblings and youngest children performed better than oldest children on some tasks. Middle children's performance did not differ significantly from that of the other children. There were correlations in performance among the measures as expected. Results are discussed in terms of whether having younger or older siblings may influence cognitive development.
Semi-parametric models for cost-effectiveness analysis: Improving the efficiency of estimation from censored data

In a cost-effectiveness analysis of clinical trial data, interest centres on the differences in mean cost and mean effectiveness between two treatment groups. One way of estimating these differences is through semi-parametric models that express a patient's expected cost and expected effectiveness as linear functions of baseline covariates, including treatment groups. Clinical trial data are often subject to right censoring, and this must be accounted for appropriately in order to obtain consistent estimates of the regression coefficients. Although this can be achieved through inverse-probability weighting, the resulting estimators may not be efficient. This thesis uses existing results on semi-parametric efficiency to suggest new "improved" estimators for the regression coefficients. When cost histories are available, estimation of mean cost becomes a multivariate estimation problem, since costs are typically auto-correlated within a patient. By specifying the semi-parametric model as a multivariate regression, this auto-correlation can be used to further improve efficiency. Two further extensions to the model are considered. The first pools information across time intervals by allowing the regression coefficients for mean cost to be the same for each interval. A test for this assumption of equality is developed. The second extension allows time-dependent covariates to be included in the model. Both inverse-probability and improved estimators for these extended models are derived. The improved estimators are evaluated through two simulation studies to demonstrate that they do improve upon the efficiency of the inverse-probability estimators. The roles of the censoring fraction, the sample size, the multivariate approach and pooling on the relative efficiency of the estimators are explored, and the adequacy of the theoretical variance estimators is evaluated. The methods are then applied to three datasets. The first two datasets are clinical trials and are used to illustrate the benefits of the improved estimators in practice. Although both the models and the simulation studies use mean survival time as the measure of effectiveness, the second dataset shows how the results can be extended to mean quality-adjusted survival time. The third dataset contains longitudinal observational data on LDL-cholesterol levels and patient costs, and calls for a regression model with a time-dependent covariate.
Sensory modality dependence of neural networks supporting simple working memory

We used functional magnetic resonance imaging (fMRI) and evoked response potentials (ERPs) to examine how the brain subserves cognitive processes when the same tasks and stimuli are presented through different modalities. The stimuli were auditory or visual bandpass-filtered white noise. On a given trial, three stimuli, each with differing center frequencies, were presented in succession. For temporal sequencing tasks, participants indicated when the stimulus with the highest frequency content appeared. For comparison tasks, participants indicated whether the last stimulus' frequency content was lower, intermediate, or higher than the first two stimuli. Task difficulty was equated by establishing 80% accuracy thresholds across subjects and tasks. For the fMRI data, we used task partial least squares (PLS) to identify activation patterns that independently map onto stimulus modality and task demands. Next, we examined PFC functional connections using seed PLS. We found that for each modality, the correlations between the right PFC and the rest of the brain were different in terms of the number of dimensions needed to capture task dependent PFC-brain correlations, and in terms of the voxels that functionally connect with the PFC, suggesting that brain activation patterns associated with modality and task demands interact. We used behavioural PLS to identify neural patterns capturing the optimal association between brain images and reaction time. This analysis also identified a significant interaction between modality and task demands, indicating that task dependent brain-behavior correlations changed with stimulus modality. For the ERP data, we used task PLS to identify the temporal interaction of neural networks that subserve modality and task demands. Source models for the task demand effect in each modality suggest that the spatial distribution of current sources are very similar outside the sensory cortices, but different in terms of time course. Specifically, information for visual processing appears to be updated and held online in a manner that is different from auditory processing, which is done mostly after the offset of the final stimulus. Overall, these results suggest that the neural substrates that support our auditory and visual working memory tasks differ outside the sensory cortices both in terms of activity and interactivity.
Exploring the parameters of retrieval mode in a recognition memory task using behavioural and event-related potential methodologies

Retrieval mode has been defined as a cognitive state that orients the cognitive system to treat items as cues for episodic memory. The present set of behavioural experiments (Experiments 1-3) and event-related potentials study (Experiment 3) sought to separate retrieval mode from other retrieval-related processes, such as retrieval success and effort, in a paradigm that cued participants to an upcoming memory task. Results were compared to performance on a cued perceptual task and on non-cued memory and perceptual tasks. The findings indicated that maintaining retrieval mode is both resource-demanding and requires processing time. ERP correlates related specifically to retrieval mode differed from both the perceptual and non-cued trials and were most evident across centroparietal electrodes during both the post-cue word onset period and test word period. Based on these results, it was concluded that posterior regions associated with item recognition memory may also be recruited in establishing and maintaining retrieval mode.
Pre and perinatal morbidity in children with Tourette Syndrome and Attention Deficit Hyperactivity Disorder: A case control study

Objective. To assess the association between pre and perinatal morbidity and comorbid ADHD in children with TS. Methods. A case control study was performed. Cases were defined as children with TS and ADHD; controls had TS without ADHD. Exposure to pre and perinatal morbidity was assessed prior to the diagnostic interview. Results. 353 children were included, 181 cases and 172 controls. Children with TS and ADHD had a greater odds of low birth weight status, prematurity, breathing problems and maternal smoking than children with TS only. A multivariable logistic regression model found adjusted odds ratios for comorbid TS and ADHD of 2.74 (95% CI 1.03-7.29, p=0.04) in children born low birth weight, and of 2.43 (95% CI 1.23-4.82 p=0.01) for children exposed to maternal smoking. Conclusion. In children with TS, there is a greater odds of comorbid ADHD in children born low birth weight or with exposure to maternal smoking.
The protest, the public and the state of the nation

"The Protestor, the Public and the State of the Nation" critically interrogates the representation of protest in the dominant news media. A thematic analysis of The Globe and Mail's reporting of the international and Canadian street demonstrations against the American-led invasion of Iraq, reveals how the rational, 'core' Canadian is problematically narrated as white, middle-class, heterosexual, able-bodied and male. This 'ideal Canadian' upholds the racist foundations upon which the state was built as it erases the numerous actors who were not reported as participating in the protests and reinforces the raced hierarchies prevalent in Canada. In this analysis Canada is understood to be a state that re-colonizes through the discursive production and reinforcement of Canadian protesters in contrast to protesters around the world. The impact of this colonial treatment of the 'core' Canadian is disrupted and finally, the study suggests actions for more inclusive and equitable knowledge production.

Keywords: Protest movements, Canada
Racism, Canada
Racism in mass media
Protest movements in mass media
Peace movements, Canada
The effect of a home-based family literacy program on parents' involvement in their children's literacy development

A wide body of research shows strong associations between parent home literacy involvement and child language and literacy outcomes, but there is little research on the factors that influence parents to become involved in early home literacy activities. This study evaluated a unique home-based family literacy program designed to support parental involvement in literacy promotion during early childhood. This study also examined the processes that may contribute to greater parent involvement by developing a conceptual model extending the parent-school involvement model developed by Hoover-Dempsey and colleagues (e.g., 1995). In the model developed for this study, five literacy-related parent factors—knowledge, efficacy, childhood memories, perceptions of child interests, and home resources—were hypothesized to be processes contributing to parents' involvement in home literacy. The evaluation of the 8-week family literacy program employed a randomized experimental research design. Participants were ninety parent-child dyads, all living in publicly-subsidized apartment buildings. Evaluation focused on treatment and control group comparisons of involvement and related processes, pre-program and post-program. The evaluation also compared pre-program and post-program prediction of parent home literacy involvement from individual differences in the related processes. The rationale for these comparisons was to test whether the program altered patterns of prediction, as another way of exploring the potential role of these processes in fostering parent home literacy involvement in children's language and literacy development. Results indicated that the program had a positive effect on the level and quality of parents' knowledge, efficacy, and home literacy involvement. Findings revealed that parents' knowledge, efficacy, perceptions of child interest, and resources predicted variance in parents' home literacy involvement both before and after the intervention and that the strength of these predictors changed for the program group. Parent knowledge and efficacy were more highly correlated with parent home literacy involvement after the program. Results are discussed in terms of future research and implications for practice.
Development of high performance hemp fibers for composite manufacturing

Hemp is an important lignocellulosic raw material for the manufacture of cost-effective environmental friendly composite materials. Hemp fibers were subjected to heat treatment in an air and in an inert environment. Hemp fibers treated in an air environment showed greater decline in weight compared with those treated in an inert environment at a temperature higher than 220°C. The overall strength of fibers treated in an inert environment was found to have increased due to the production of smaller diameter fibers while fibers treated in air showed decline in strength even though fibers opened up. Further opening of fibers were achieved by ball milling. Surface energy of treated fiber increased due to heat treatment resulting in lower polarity. Inert environment treated fibers were found to have a lesser moisture uptake rate compared to untreated fibers. Composites prepared from treated fibers showed improved resistance to moisture uptake and heat distortion temperature.
Managerial incentive structures, conservatism and the pricing of syndicated loans

Drawing on previous theoretical research, this thesis empirically explores the effect of manager-shareholder incentive alignment, as measured by the extent of equity compensation, on the pricing of syndicated loan contracts. Two principal findings are reported. First, this thesis documents that high levels of alignment are associated with larger risk premiums in loan spreads and more restrictive covenants. The potential endogeneity of managerial compensation contracts is dealt with by implementing a Propensity Score Matching methodology. Second, this thesis documents the effects of ex ante accounting conservatism on loan pricing terms, conditional on the managerial incentive structure as a proxy for managerial ex post reporting incentives. More specifically, it provides evidence that ex ante accounting conservatism decreases loan spreads and increases the number of financial covenants in the loan contract when managers receive average or below-average equity compensation. However, when managers receive above-average equity compensation, ex ante conservatism leads to banks demanding larger loan spreads as well as fewer and tighter financial covenants. These latter results are consistent with the interpretation that banks view ex ante conservatism as an instrument for reducing the monitoring value of financial covenants when managers have incentives to over-report ex post due to large equity compensation.

Keywords: Accounting
Dissertations, Academic, Canada
The recovery of sinapic acid from the waste permeate from yellow mustard protein isolation

A process for recovering sinapic acid from waste permeate generated from processing yellow mustard protein isolate has been developed. Due to the low concentration of solids in the waste permeate, a nanofilter with molecular weight cut-off of 1000Da was used for removing most of the water. The volume of starting material was concentrated 5-fold, whilst approximately 74% of sinapine was retained. Sinapic acid was then released from sinapine, an esterified form, by an alkaline hydrolysis with 4M NaOH for 4 hr. The hydrolyzed solution was acidified to pH 2 to prevent oxidation of the sinapic acid and to precipitate the remaining proteins. As a result, more than 84% of the permeate protein was precipitated, and was subsequently removed using centrifugation. Sinapic acid and other phenolics were extracted by an organic solvent system (diethyl ether and ethyl acetate (1:1)). Under the optimum extraction conditions approximately 95% of the sinapic acid was extracted to the solvent phase. Sinapic acid was further purified by strong basic ion-exchange chromatography. Approximately 19 bed volumes of the solution containing sinapic acid obtained from the previous extraction step were fed to the chromatographic column at 30 mL/min before sinapic acid absorbed by the resins was eluted with a mixture of methanol and 1 M acetic acid (4:6). The effluent obtained from the elution process was freeze-dried to obtain a purified product. More than 38% of the sinapic acid from the starting waste permeate was finally recovered and the resulting product contained about 85% of total phenolics (81% sinapic acid and 1.7% of p-hydroxybenzoic acid). The recovered product was tested for its antioxidant activity with the DPPH radical scavenging method. Data derived from the tests showed that the potencies in terms of EC50 between the recovered product and a pure commercial sinapic acid were comparable.
Microfiltration based process for the production of mustard protein isolates

The feasibility of using microfiltration to separate proteins from extract of dehulled yellow mustard flour was investigated. The dehulled yellow mustard flour was extracted at pH 12 for 30 minutes with water-to-solid ratio of 18. Approximately 90% of the protein was extracted. The pH of alkaline extract was adjusted to 10 without adding NaCl before passing through microfiltration. A concentration factor of 3 was most suitable for microfiltration. Precipitated protein isolates (PPI) from the retentate contained 71.2% of protein (Nx6.25) with 20.2% of oil content, while PPI from the permeate was oil-free and contained 97.0% of protein. Both PPIs were found to be free of glucosinolates and phytate; however, phenolic compounds were detected in these products. The protein content of the meal residue was 9% with 34.8% of oil content, whereas soluble protein isolates (SPI) from the retentate and permeate were oil-free with 23.3 and 33.5% of protein content, respectively.