Thèses, 1910 - 2010 // Theses, 1910 - 2010

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Médéric Lanctôt et l'Union nationale
(1968) Gervais, Gaëtan
Anti-diabetic and neuroprotective activities of phytochemicals in traditionally used boreal plants
(University of Ottawa (Canada), 2008) Harris, Cory S
This thesis investigated the phytochemistry and pharmacology of boreal plant species used traditionally as treatments for symptoms and complications of diabetes and was completed in collaboration with the Team in Aboriginal Anti-Diabetic Medicine and the Cree of Eeyou Istchee in northern Quebec. Using a novel metabolomic-based approach, we first developed methods of phytochemical analysis to characterize Vaccinium angustifolium extracts and then other medicinal Ericaceae, identifying and quantifying an abundance of phenolic compounds. These methods were then employed to profile the phenolics in anti-diabetic species identified by Cree Elders. Pharmacological assays of extracts focused primarily on in vitro inhibition of mechanisms involved in the pathophysiology of diabetic neuropathy, associated diabetic complications and neurodegenerative conditions. Upon testing for cytoprotective effects in two models of diabetic neuropathy, few extracts prevented cell loss mediated by serum/glucose deprivation but 10 of 18 significantly reduced glucotoxic cell death. The activities of Picea glauca needles, which was cytoprotective in both models, and Sarracenia purpurea leaves were of particular interest as observed organ-specific effects correlated with medicinal uses identified by Cree Elders. Cytoprotection, however, did not correlate with extract phenolic content or anti-oxidant activity. Active principles were therefore sought through assay-guided fractionation of S. purpurea extract, identifying quercetin-3- O-galactoside, which inhibited glucotoxicity at low micromolar concentrations. Extracts were then tested for effects on formation of advanced glycation endproducts. Most displayed concentration-dependent inhibition with IC50 values ranging from 0.4-38.6 mug/ml. Anti-glycation activity was significantly correlated with extract phenolic content and anti-oxidant capacity. The bioactivities of individual phenolic metabolites were then evaluated at physiologically relevant concentrations using molecular tools to determine cell proliferation, survival and death. A wealth of anti-apoptotic and mitogenic effects were observed and structure-activity relationships were separately identified among benzoic acid derivatives and flavonoids. To explore the neuroprotective potential of these two phenolic classes, collections of each were tested for the ability to inhibit platelet-activating factor (PAF) neurotoxicity. Three novel PAF inhibitors were identified, orsellinic acid, hesperetin and quercetin, and all prevented PAF-mediated executioner caspase activation. Together, these results validate the traditional knowledge shared by our Cree collaborators and highlight the multidimensional therapeutic potential of boreal plants as culturally appropriate complementary anti-diabetic therapies.
Quand le coeur n'y est plus: le désengagement psychologique au travail et dans le milieu scolaire
(University of Ottawa (Canada), 2011) Laplante, Joëlle
Tous ne sont pas égaux dans la société. Lorsque les individus reconnaissent leur situation de désavantage et en sont insatisfaits, un sentiment que les auteurs ont qualifié de privation relative, certains choisissent de réagir à leur situation désavantageuse ouvertement et d'autres optent plutôt pour des réactions silencieuses. Dans les quatre études présentées, nous focalisons sur un type précis de réaction souterraine en réponse à la privation relative, soit le désengagement psychologique. Cette stratégie qui, selon les hypothèses de départ, protège l'estime de soi, peut s'effectuer par le biais de deux mécanismes : le discredit du feedback et des évaluations et la dévaluation du domaine dans son ensemble. Les quatre études presentées dans cette thèse portaient principalement sur les antécédents et les conséquences du désengagement psychologique. La première étude, réalisée par questionnaire auprès d'un groupe d'employées de bureau (N = 154) avait pour but de déterminer si le recours aux mécanismes de désengagement psychologique diffère selon le type de comparaisons (sociales ou temporelles) donnant lieu à la privation relative. Les résultats de la modélisation par équations structurales font état d'une certaine stabilité au niveau de l'adoption des mécanismes de désengagement suite aux sentiments de privation relative. En revanche, la deuxième étude, menée auprès d'éducatrices et d'aides enseignantes (N = 106), démontre qu'être un laissé-pour-compte dans son milieu professionnel, mesure par la privation relative intragroupe, peut entraîner une baisse de l'identification au groupe et renforcer de façon indirecte le retrait non plus psychologique, mais effectif du domaine. La troisième étude, une méta-analyse recensant les réponses de 4351 participants (30 échantillons distincts), infirme l'hypothèse de l'effet protecteur du désengagement psychologique sur l'estime de soi : il a été démontré que le discrédit et la dévaluation blessent. De plus, plusieurs modérateurs ont été évalués afin d'expliquer la variance observée au niveau des résultats d'études antérieures. Les résultats indiquent, par exemple, que les blessures infligées par le discrédit et la dévaluation dans le milieu scolaire sont moins graves que celles dans le milieu de travail. Dans la foulée de cette méta-analyse, la quatrième étude a été menée par questionnaire auprès d'un groupe d'étudiants francophones en situation minoritaire (N = 107), afin d'évaluer l'apport de facilitateurs du désengagement psychologique. Il a été démontré que les étudiants dont l'estime de soi est liée à l'approbation des autres répondent davantage à la privation relative par le discrédit ; de plus, les résultats suggèrent que ce recours au discrédit suscite une plus forte baisse de l'estime de soi lorsque l'étudiant n'attribue pas de sens ou de signification psychologique à la poursuite des études. En somme, les quatre études ont permis de démontrer que 1) le désengagement psychologique peut être provoqué par les privations relatives sociale, temporelle et intragroupe ; 2) le recours au désengagement psychologique peut être provoqué par un traitement différentiel relié à des stigmas non visibles, comme le groupe professionnel et la langue ; 3) certains facteurs peuvent modérer le recours au désengagement psychologique ; 4) la séquence d'adoption des mécanismes de désengagement est plutôt stable mais l'identification au groupe mené plus directement à la dévaluation du domaine ; et 5) les mécanismes de désengagement psychologique ont un effet néfaste sur l'estime de soi ; 6) certains facteurs peuvent rendre l'un ou l'autre de ces mécanismes plus dommageable à l'estime de soi.
Analyse des cohérences intra, inter et extra des réformes académiques du Congo-Zaïre (1971--2003)
(University of Ottawa (Canada), 2011) Mpevo Mpolo, Aimé
Cette recherche porte sur la cohérence intra, inter et extra des quatre réformes universitaires décidées au Congo-Zaïre en 1971, 1981, 1989 et 2003. L'analyse de la cohérence intra a cherché à savoir dans quelle mesure, pour chacun des 16 objets habituels des réformes académiques, chaque politique de ces quatre réformes se tient en elle-même. L'analyse de la cohérence inter a chérché à savoir dans quelle mesure chaque nouvelle réforme constituait, pour chacun des 16 objets, une amélioration des ratés et des insuffisances de la réforme précédente, et dans quelle mesure il y a eu une amélioration des politiques depuis la première jusqu'à la quatrième réforme. L'analyse de cohérence extra a cherché à savoir dans quelle mesure ces réformes ont été rigoureusement ancrées vis-à-vis de la trajectoire des besoins de développement de la société nationale. Pour y arriver, conformément à la méthode historique positive, nous avons procédé à une analyse de contenu des documents d'archives collectes au Congo Kinshasa. Mais face à la carence d'études et de modèles conceptuels sur l'analyse des cohérences intra, inter et extra des politiques d'Enseignement tertiaire, nous avons dû modifier et adapter des modèles conceptuels élaborés pour d'autres fins. Ces modèles, plus adaptés, sont : le modèle des 16 objets d'une réforme académique, le modèle de consistance et adéquation (cohérence intra), le modèle cyclique des politiques (cohérence inter), les modèles d'environnement scientifico-économique, social, politique, et culturel de l'Université (cohérence extra). Les résultats sur la cohérence intra montrent qu'à quelques exceptions près, les politiques alignent des stratégies inadéquates notamment quant à la prévision des ressources financières et humaines, et quant aux attitudes des agents de la mise en oeuvre. L'analyse de cohérence inter révèle entre les politiques analogues des réformes consécutives : l'abandon de problèmes non résolus, le non-suivi de résultats désastreux, et la réiteration d'inadéquations de stratégies. L'analyse de cohérence extra montre une absence de concordance entre l'évolution de la société en ses secteurs principaux et l'évolution de l'Enseignement tertiaire régie par les réformes. Par ricochet, l'étude révèle aussi la validité des modèles conceptuels employés dans l'analyse. La présente recherche est une réponse à une double pénurie : pénurie de recherche sur la cohésion, l'amélioration et l'insertion sociétale des politiques académiques du Congo-Zaïre; pénurie de recherche sur l'analyse de cohérence des politiques d'Enseignement tertiaire, et inexistence d'une tradition méthodologique relativement à ce champ des Sciences de l'éducation.
Asymptotic Results for Some Longitudinal Regression Models
(University of Ottawa (Canada), 2011) Dumitrescu, Laura
The scope of this thesis is to examine asymptotic properties for some longitudinal regression models. These models are often used in biostatistics, econometrics and psychology and involve the collection of several measurements, at different occasions, on the same individuals or clusters. First, we examine the classical regression model for longitudinal data and define the asymptotically optimal estimating equation, with strongly consistent solutions. Then, we consider a simple model with error in covariates, adapted to longitudinal data, obtain estimators of the regression parameters and examine their asymptotic behavior.
The Determinants of Skills of Canadian Immigrants
(University of Ottawa (Canada), 2011) Hou, Yan Betty
In this thesis, I present two empirical analyses to help understand the following question: Why do Canadian immigrants, despite their higher levels of education, have lower level of skill proficiencies than the native-born population in Canada? The first empirical analysis uses country-level macroeconomic data, while the second is conducted with individual level microeconomic data taken from International Adult Literacy Skill Survey (IALSS). In addition, the macro level and micro level results are compared at the end of the thesis. In the first part (Chapter 2), I summarize and synthesize the findings of previous research that addresses or helps in understanding the main questions analyzed in this thesis. I discuss the various approaches used to measure human capital and suggest that the literacy proficiency scores provided by IALSS are a more appropriate indicator than the commonly used educational data. I also discuss the various factors that play a role in the formation and development of immigrants' human capital, such as the income-per-capita in the country of origin, language proficiency, and education. The various data used in this thesis are discussed in Chapter 3. I have refined the coding of the country of origin in the original Master file of IALSS, extending the number of cross-sectional units from 28 countries to 50 countries/country-groups for the macro analysis. This is one contribution of my work, since the increase in the number of observations improves the robustness of the empirical analysis. The empirical analysis that used country-level macro data is carried out and presented in Chapter 4. All the results strongly suggest that the economic development level of the country of origin, proxied by the income per capita, is a key determinant of the immigrants' skill proficiency. The language barrier also plays an important role in explaining why immigrants have more years of schooling but lower skill proficiencies in Canada than the Canadian-born people. I also estimate regressions using employment earnings. The results concur with the analysis of Hanushek and Woessmann (2008), who show that education which did not contribute to cognitive skills will not affect the economic outcomes of immigrants. In Chapter 5, I turn to individual-level micro data to examine the factors linked with immigrants' skill proficiency. The micro level evidence also suggests that a country's economic development level that existed during an individual's schooling age plays an essential role for his/her future skill proficiency. The similar marginal effect for Canadian education and foreign education when income-per-capita of country of origin is under controlled suggests that income-per-capita of country of origin is a good proxy of quality of education. A comparison between individual and aggregated level regressions is discussed as well. Both micro-level and macro-level analyses provide consistent findings that income-per-capita of country of origin, years of schooling, and language proficiency in English/French have significant influences on immigrants' skill development. This type of comparison has not been conducted in previous studies in investigating the formation and development of immigrants' cognitive skills, and is considered as another contribution of this thesis.
Characterization of the role of the medial prefrontal cortex and the amygdala in fear and anxiety: a focus on bombesin-like peptides and corticotropin-releasing hormone
(University of Ottawa (Canada), 2010) Mountney, Christine
This dissertation aimed to more fully characterize the involvement of bombesin-like peptides (neuromedin-B [NMB] and gastrin-releasing peptide [GRP]) and corticotropin-releasing hormone (CRH) in fear and anxiety-related processes. To this end, ventricularly injected GRP and antagonists of the NMB receptor decreased fear and/or anxiety across several animal models of behavior. Whereas NMB appeared to be involved in both fear and anxiety-related processes, GRP affected fear-related processes. In order to determine where in the brain these effects might be primarily localized, several neurochemical alterations were assessed in brain areas known to be involved in fear. Endogenous alterations in peptide levels were seen both within the medial prefrontal cortex (mPFC) and amygdala in response to recall of a fear-inducing shock. To explore this finding further, GRP or its receptor antagonist were microinjected into specific nuclei in the aforementioned areas and it was found that GRP consistently reduced fear at these loci, while the receptor antagonist exhibited both agonistic (reduced freezing) effects as well as antagonistic effects (increased freezing). Further, the observed reductions in freezing appeared to be specific to contextual components of conditioned fear, with the exception of drug administration to the infralimbic (IL) cortex within the mPFC, where we saw reduced freezing to a conditioned tone as well. To determine the endogenous release of GRP and CRH in response to conditioned fear, we collected dialysates from the IL of the mPFC and basolateral amygdala (BLA) in response to a previously conditioned tone. GRP and CRH were elevated 24h after fear conditioning at the BLA, an effect that appears to be related to animal's levels of fear. This was not observed at the IL. Finally, we explored whether the mPFC and amygdala communicated with each other via GRP and/or CRH through a GRP-specific pathway(s). We found that there appears to be a functional pathway between the IL cortex and BLA that is specific to GRP but not to CRH, upon manipulation of IL GRP levels. These studies have further characterized the role of BLPs and CRH in conditioned fear, particularly at the level of the mPFC and BLA and have provided a unique and rich foundation for the physiological role of these peptides and future studies to be developed.
Relations des facteurs de risque et de protection avec les symptômes dépressifs et l'usage de substances chez les jeunes de l'Ontario
(University of Ottawa (Canada), 2011) La Roche, Michèle
Plusieurs facteurs de risque et de protection influencent le parcours psychosocial des adolescents et l'émergence de problèmes de comportement ou de santé mentale. Ces facteurs peuvent apparaître dans différents milieux de vie (communauté, famille, école, pairs) et appauvrir le bien-être des jeunes, pendant l'adolescence et même au-delà. Afin de mieux connaître l'importance de ces facteurs et de leurs relations avec les symptômes dépressifs et avec l'usage de substances (cigarette, alcool et cannabis), le sondage CTC-YS (Communities That Care-Youth Survey) a été administré en 2006 et 2007 dans deux régions de l'Ontario auprès de 4 600 élèves de la sixième à la douzieme année fréquentant les écoles anglaises et françaises. Cette première exploration en contexte bilingue de 23 facteurs de risque et 11 facteurs de protection et de leurs relations avec les symptômes dépressifs, le tabagisme, la consommation d'alcool et l'usage de cannabis montre des différences, quoique modestes, entre les élèves des écoles anglaises et françaises. Dans les deux échantillons, les élèves des écoles anglaises avaient des niveaux plus élevés de facteurs de risque et de symptômes dépressifs que ceux des ecoles francaises, et des niveaux plus faibles sur plusieurs facteurs de protection. Cependant, les relations individuelles entre ces facteurs et les problèmes s'équivalaient pour les deux groupes. Les symptômes dépressifs et leurs relations avec une grande majorité de facteurs de risque s'avéraient plus élevés chez les filles que chez les garçons. En contrepartie, les facteurs de protection, dans les domaines de la famille, de l'école et des pairs, les avantageaient. Les adolescents plus jeunes semblaient plus vulnérables à l'usage de substances que les adolescents plus âgés, certaines relations avec les facteurs de risque étant plus marquées, mais les facteurs de protection dans les domaines de la famille et des pairs jouaient en leur faveur. La discussion porte sur la pertinence de l'utilisation du sondage CTC-YS en milieu ontarien bilingue pour la prévention de difficultés comportementales et de santé mentale, et sur l'importance d'offrir des interventions multidimensionnelles favorisant à la fois l'augmentation des facteurs de protection et la'diminution des facteurs de risque dans les divers milieux de vie des jeunes.
The Implications of Future Time Perspective and Planning Ability for Children's Emotion Regulation
(University of Ottawa (Canada), 2011) Puddester, Leah M
Studying emotion regulation in childhood has particular importance for understanding the developmental trajectory of these abilities, as well as for informing preventative work that could offset later psychopathology. Gross (1998a) has distinguished between antecedent- and response focused emotion regulation strategies, and has shown that emotion regulation strategies that occur earlier in the emotion generative process have more favourable outcomes. The first step in antecedent emotion regulation is situation selection, which involves seeking out or avoiding certain situations or environments in order to regulate emotion. In fact, there is a growing psychological literature on children's environmental choices, or environmental niche picking, and how they may affect self-regulatory processes such as emotion regulation. To date, most research has focused on environmental choices for preferred (favourite) environments, and little attention has been focused on non-preferred environments, namely the school playground - the predominant social environment in which children spend their formative years. One's ability to plan, think about the future, and delay immediate gratification are also thought to be important factors in antecedent focused emotion regulation, as such skills allow an individual to move beyond immediate concerns. Few studies have investigated the relationship between emotion regulation and children's future time perspective and planning ability. The present study sought to add to existing research on emotion regulation by investigating the mechanisms by which children develop healthy emotion regulation skills. It was hypothesized that children who scored higher on future time perspective and planning ability would demonstrate better emotion regulation and be rated by peers as less aggressive. It was also hypothesized that any relationship between emotion regulation and aggression would be mediated by future time perspective and/or planning ability. Participants were 82 elementary school students in grades 3 (13 females, 15 males), 4 (17 females, 13 males), and 5 (17 females, 7 males). Parents and homeroom teachers of children also participated by completing the Lability/Negativity scale of the Emotion Regulation Checklist (Shields and Cicchetti, 1997). Children completed peer nomination measures of social behaviour using the Revised Class Play (Masten, Morrison, and Pellegrini, 1985) and one measure of emotion regulation, the Environmental Choices task (Ledingham, Rafter, & Genot, 1995). Children also completed two measures of means-end thinking: the Children's Time Perspective Inventory (Myers, 2000), and the Woodcock-Johnson III Test of Cognitive Abilities - Planning subtest. Results indicated that children as young as the age of 7 could be classified as having a future time perspective, and that future time perspective significantly predicted peer nominations of children's aggression. In addition, children's planning ability, as measured by the Woodcock-Johnson, played a significant role not only in predicting children's self-reported emotion regulation reasons for environmental choices, but also in accounting for parent ratings of children's emotion regulation. This study also highlighted the importance of environmental niche picking for emotion regulation, with a majority of children indicating that they actively used different locations on the playground to help them regulate their negative emotional states. Contrary to hypotheses, there was no evidence that future time perspective or planning ability mediated the relationship between emotion regulation and aggression. Limitations and implications of the current findings are discussed.
Criminalizing Adolescence? Understanding Probation and Probation Violations in the Canadian Youth Criminal Justice System
(University of Ottawa (Canada), 2011) Latimer, Jeff
Youth probation in Canada is a critical yet clearly under-researched area within Criminology. Probation is the most common sentence in youth court yet many youth fail to comply with the conditions laid out by the courts. This thesis represents the results of an in-depth examination of probation cases in the youth criminal justice system with a focus on probation violations and Probation Officer discretion. All closed administrative probation files within an Ontario area Probation Office during the year 2005 were selected (N=299) in order to examine the nature and extent of probation violations. In addition, 7 Probation Officers were interviewed to supplement the file review and answer questions that were outside the scope of the administrative files. The findings reveal that the majority of youth within the probation system have a substantial number of serious psycho-social issues. Youth serving probation sentences are also subject to considerable social control through the imposition of numerous probation conditions covering many aspects of their lives. Yet most youth violate one or more of these conditions, usually by engaging in relatively typical adolescent behaviour such as staying out late, drinking alcohol or skipping school. Only a minority of these youth, however, are actually charged with a violation under s. 137 of the Youth Criminal Justice Act. The implications of this research for judges, Probation Officers, policy-makers and researchers are discussed.
Photonic generation and processing of microwave arbitrary waveforms based on advanced fiber Bragg gratings
(University of Ottawa (Canada), 2011) Wang, Chao
Photonic generation and processing of microwave arbitrary waveforms has been a topic of interest recently. Compared with the electronic techniques, photonics techniques provide the capabilities of generating and processing high-frequency and large-bandwidth microwave waveforms which cannot be fulfilled by the electronic techniques. In this thesis, techniques to generate and process microwave arbitrary waveforms in the optical domain using advanced fiber Bragg gratings (FBGs) are investigated, with an emphasis on the system architectures in which FBGs are employed as spectral shapers and dispersive elements. The thesis consists of two main parts. In the first part, we investigate the generation of a microwave arbitrary waveform using advanced FBGs. Two techniques to generating microwave arbitrary waveforms based on coherent optical pulse shaping are investigated. The first technique is based on optical spectral shaping and frequency-to-time mapping. The use of an FBG as an optical filter to achieve spectral shaping, as a dispersive element to achieve frequency-to-time mapping, and as a multifunctional device to perform both optical spectral shaping and frequency-to-time mapping is investigated. In the second technique, the photonic microwave arbitrary waveform generation is realized based on Fourier-transform pulse shaping. Time-domain Fourier-transform pulse shaping is first studied, where a pair of linearly chirped FBGs is employed as dispersive elements to temporally stretch and compress the input optical pulse. Fourier-transform pulse shaping is also implemented in the frequency domain, where a linearly chirped FBG functioning as both an optical spectral shaper and a conjugate dispersive element pair to perform pulse stretching and pulse compression is employed. In the second part, we investigate the photonic processing of a microwave arbitrary waveform using advanced FBGs. A photonic microwave filter is usually used to process microwave signals in the optical domain. Two different photonic microwave filters are explored. The first filter is a nonuniformly spaced photonic microwave multi-tap delay-line filter, which is designed to have a quadratic phase response to achieve matched filtering of a frequency-chirped microwave waveform. A spatially-discrete chirped fiber Bragg grating (SD-CFBG), which can be designed to arbitrarily control the tap coefficients and the time delays, is utilized in the multi-tap delay-line filter to achieve the desired microwave filter response. The second photonic microwave filter is implemented based on optical filter response to microwave filter response conversion in which an FBG with the desired magnitude and phase response is employed as the optical filter. The employment of the photonic microwave filter for matched filtering of a frequency-chirped microwave waveform is demonstrated.
Using Evolutionary Inspired Search Methodologies To Explore Polymorphism or Defect Associations in Materials Design
(University of Ottawa (Canada), 2011) Hooper, James
The work presented in this thesis reinforces the notion of how powerful evolutionary search methodologies, specifically those inspired by the genetic algorithm (GA), are when applied to search out the chemical and/or configurational spaces of a number of chemical systems. Researchers in the field often sell the capability of GA search techniques to operate without constraints but, as is demonstrated in this thesis, sometimes the use of constraints can not only streamline computational costs but open up new avenues to explore in materials design. As a starting point, this work first focuses on developing effective methodologies that map out nitrogen's high-pressure potential energy surface (PES) such that polymeric nitrogen, a relatively new material with a potentially promising outlook in future high-energy density materials applications,¹ could be explored. High pressure nitrogen (> 30 GPa) is an ideal candidate to explore theoretically since conclusive experimental characterizations are often beyond the reach of current laboratory technologies.² Theoretical and experimental assessments of polymorphism in high-pressure nitrogen have been reported in the recent literature,³ and, upon the inception of this thesis, much of its potential energy surface remained unmapped. Using both established and novel search methodologies on nitrogen's high-pressure potential energy landscape, with GA-inspired methodologies included among them, a number of previously unreported allotropes of molecular and non-molecular nitrogen at high pressures are reported which relate well with experimental studies. The second focal point of this thesis is to present a general methodology capable of mapping generic defect associations in doped metal oxides. Doped metal oxides have many applications as substrates in catalysis, as gas sensors, and as next generation solid electrolytes in solid-oxide fuel cell technologies, just to name a few. The performance of these metal oxide materials can be enhanced (or, more generally, tuned) via doping of the parent oxide with other elements at varying concentrations; however, the optimization of the dopant composition is often performed by trial and error. By introducing appropriate constraints, GA-inspired routines can sample the configurational and chemical spaces of any defects introduced to a native oxide lattice. Thus, genetic algorithms are used herein in two capacities: 1) to find the lowest energy configurations of a specific metal oxide composition and 2) to search a doped metal oxide's chemical space in order to optimize a specific property of interest based on a given 'fitness' metric. This approach is validated by optimizing electronic mobility in doped zinc oxide, which is used in gas sensor technologies, and ionic mobility in Lanthanide doped ceria (LDC), which is used as a solid electrolyte in solid-oxide fuel cell technologies. ¹M. I. Eremets, A. G. Gavriliuk, I. A. Trojan, D. A. Dzivenko, and R. Boehler, Nature Materials 3, 558 (2004). ²E. Gregoryanz, C. Sanloup, R. Bini, J. Kreutz, H. J. Jodl, M. Somayazulu, H.-k. Mao, and R. J. Hemley, Journal of Chemical Physics 124, 116102 (2006). ³W. D. Mattson, D. Sanchez-Portal, S. Chiesa, and R. M. Martin, Phys. Rev. Lett 93, 125501 (2004).
The power of the diocesan bishop with regard to the administration of ecclesiastical goods of public juridic persons subject to him: An analysis of canon 1276, section 2
(University of Ottawa (Canada), 2011) Omorogbe, Edwin N
The current norms on the administration of temporalities demand a new openness and a mutual trust between those who administer Church property and those who donate temporal goods to the Church. The entire matter of regulating how donated goods are managed is the subject matter of canon 1276. Canon 392, §2 stipulates that the diocesan bishop has an obligation to ensure that abuses do not creep into the administration of ecclesiastical goods. The legislator recognizes the fact that if abuses creep into the administration of ecclesiastical goods this will damage the credibility of the Church. The transparency and accountability of administrators are vital to sustaining this credibility. How is the diocesan bishop to ensure this transparency and accountability? The specific way of achieving this is the subject matter of our dissertation. In order to achieve this goal the dissertation was divided into four chapters. The first chapter examined the power of the diocesan bishop with regard to caring for ecclesiastical goods. The second chapter studied the roles of those who administer ecclesiastical goods. The third chapter examined the very nature of the special instructions that the diocesan bishop is expected to issue for administrators, while the fourth chapter considered the contents of this special instructions. Ecclesiastical goods assist the Church in fulfilling its mission. There is a correlation between ecclesiastical goods and the mission of the Church. Therefore, the mission of the Church is the same as the reasons why a public juridic person own goods. The same concern and due diligence that is shown to ensure that abuses do not creep into the proper celebration of the sacraments is to be shown to ensure the proper administration of ecclesiastical goods (c. 392, §2); We strongly hold that the obligation to issue special instructions for administrators of ecclesiastical goods is one of the major functions of a diocesan bishop, a function that he must consider as part of the mission which has been entrusted to him to fulfill. The special instructions serve as a canonical proactive measure to forestall possible financial malfeasance within the Church. If the Church is to avoid expending its energy and ecclesiastical resources in solving financial crisis in the future, the diocesan instruction for administrators of ecclesiastical goods should be a must for all dioceses.
Defining the Budding Yeast Chromatin Associated Interactome
(University of Ottawa (Canada), 2011) Lambert, Jean-Philippe
The identification of protein-protein as emerged as a powerful tool to characterize biological systems. In budding yeast in particular, systematic mapping of protein-protein interactions for most open reading frames drastically improve our understanding of this model organisms. Still, some classes of proteins, such as DNA binding proteins, remain poorly studied due to a lack of proper tools for their study. In this thesis, I describe the development of a novel affinity purification approach for the characterization of DNA binding proteins and of their associated proteins. The modified chromatin immunopurification (mChIP) approach consist of a single affinity purification step whereby chromatin-bound protein networks are isolated from mildly sonicated and gently clarified cellular extracts using magnetic beads coated with antibodies. The mChIP method was characterized in details demonstrating significant gain in sensitivity toward the determination of DNA binding protein interactome. Moreover, I showed that mChIP purification were successful for multiple class of proteins including numerous non-histone DNA binding proteins. Following the successful development of the mChIP method, I embarked on a large-scale characterization of chromatin associated proteins in budding yeast. In this way, 102 different DNA binding proteins were characterized by mChIP to determine their chromatin associated protein networks. This effort resulted in the detection of 3576 high confidence protein associations with 724 distinct preys. Approximately 75% of the baits had significantly improved interaction coverage using mChIP compared to the classical affinity purification methodologies. I also utilized the mChIP approach to perform targeted study of histone chaperones and unravel their interconnection. In summary, the mChIP method that I developed now makes it possible to systematically study chromatin associated proteins in budding yeast, breaking down a technical barrier that existed in the field of chromatin research for too long.
Exploration of Ligand Effects, Substrate Effects and Reactor Effects on Macrocyclization via Ring-Closing Metathesis: A Rational Approach to Efficient Cyclization
(University of Ottawa (Canada), 2011) Monfette, Sebastien
Olefin metathesis is credited with having transformed the way chemists think about the manipulation of C=C bonds, the success-story of which culminated in the highest of accolades to Schrock, Grubbs and Chauvin in 2005. It is, however, difficult to reconcile the groundbreaking effect that olefin metathesis had on organic synthesis, with its limited industrial applications. Nearly twenty years following the publication of the first well-defined Ru metathesis catalyst, the RCM reaction remains largely confined to the research setting. The low turnover numbers achieved by the Grubbs catalyst is the chief limiting factor preventing industrial uptake. Clearly, more efficient catalysts and reaction methodologies are needed to render RCM industrially viable. This thesis describes various approaches towards this goal. As macrocyclic targets are highly prized in the industry, a mechanistic investigation of their formation by the Grubbs and pseudohalide catalysts was performed. This study revealed that different reaction pathways are operative for different catalysts. While the first-generation catalyst effects RCM macrocyclization by the traditional, direct path, the second-generation catalysts afford macrocyclic products through a concentration dependent oligomerization-backbiting pathway. The second approach employs structure-activity relationship to examine the effect of the anionic ligands on metathesis activity. This study unambiguously showed, for the first time, that activity correlates with the electron-donating capacity of the anionic ligands. Therefore, incorporation of less electron-withdrawing anionic ligands was sought and the synthesis of nitrogen-bound pseudohalide catalysts was carried out. Gratifyingly, the isocyanate catalyst showed remarkable reactivity at room temperature. Polymers of well-defined chain length and low polydispersity could also be obtained with this catalyst, a task that has so far eluded all of the O-bound pseudohalide catalysts. Lastly, an examination of the effect of the reactor on RCM macrocyclization efficiency was performed. An appropriate choice of continuous-flow reactor resulted in the transformation of RCM efficiency. Much faster reaction kinetics were obtained using continuous-flow reactors. Furthermore, the attainable turnover numbers are one order of magnitude higher than those using the traditional batch setup.
Producing the Whitestream: Micropolitics and the Persistence of Colonialism in Canada
(University of Ottawa (Canada), 2011) Krebs, Andreas
This thesis examines how colonialism shapes the contemporary political landscape in Canada, particularly the daily life of mainstream citizens. I hold that colonialism lies at the root of contemporary issues of identity, diversity, pluralism, multiculturalism, citizenship and belonging in Canada. Canadian scholarly work has examined the problem of colonialism in relation to history, theory, and in terms of justice and the law. However, most of these perspectives disregard the importance of colonialism as a lived experience, and have difficulty explaining its persistence after having been abandoned as official state ideology, following the advent of modern treaties and land claims, the entrenchment of Aboriginal Rights in the Constitution, and the official policy of multiculturalism. Contrary to the dominant trend in this scholarship, colonialism persists in Canadian political life and manifests itself in a variety of ways. To this end, this thesis explores both the reproduction and transformation of colonialism in Canada, arguing that micropolitical processes of subject formation embed colonialism within the Canadian social and political fabric, reproducing the mainstream as a whitestream. I examine these processes through three sites: talk radio, humour, and sport, focusing particularly on how these sites maintain the dominance of the white, male, anglophone subject position. First, I analyze how two nationally broadcast programs with opposing political perspectives -- Sounds Like Canada and Adler Online -- mobilize sympathy and outrage, and how the production of these affective states reinforces a colonial perspective. Next I examine both popular and academic literature and media relating to hockey in Canada. Discourse on hockey in Canada embodies the nation as white and male, positioning history in terms of nostalgia, and space in terms of recreation. Finally, I analyze a series of in-depth interviews with white, male anglophones focusing on how they practice and experience "disparagement humour" in their daily lives. I examine the form that disparagement humour takes in an era marked by official multiculturalism, and how such humour may both reinforce and undermine the persistence of colonialism. I conclude with a discussion linking James Tully's democratic constitutionalism to the Deleuzian concept of the encounter, arguing that micropolitical techniques of the self enable an unsettling of the violence of colonialism.
Teacher Perceptions of the Integration of Laptop Computers in Their High School Biology Classrooms
(University of Ottawa (Canada), 2011) Gundy, Morag S
Studies indicate that teachers, and in particular science teachers in the senior high school grades, do not integrate laptop computers into their instruction to the extent anticipated by researchers. This technology has not spread easily to other teachers even with improved access to hardware and software, increased support, and a paradigm shift from teacher-centred to student-centred education. Although a number of studies have focused on the issues and problems related to the integration of laptops in classroom instruction, these studies, largely quantitative in nature, have tended to bypass the role teachers play in integrating laptop computers into their instruction. This thesis documents and describes the role of Ontario high school science teachers in the integration of laptop computers in the classroom. Ten teachers who have successfully integrated laptop computers into their biology courses participated in this descriptive study. Their perceptions of implementing laptops into their biology courses, key factors about the implementation process, and how the implementation was accomplished are examined. The study also identifies the conditions which they feel would allow this innovation to be implemented by other teachers. Key findings of the study indicate that teachers must initiate, implement and sustain an emergent and still evolving innovation; teacher perceptions change and continue to change with increased experience using laptops in the science classroom; changes in teaching approaches are significant as a result of the introduction of laptop technology; and, the teachers considered the acquisition and use of new teaching materials to be an important aspect of integrating laptop computers into instruction. Ongoing challenges for appropriate professional development, sharing of knowledge, skills and teaching materials are identified. The study provides a body of practical knowledge for biology teachers who are considering the integration of laptops into their instruction. The results are of interest to science teachers, those whose decisions affect the meaningful integration of technology in science education, those researching the teaching of science in secondary schools and those who prepare science graduates to teach at this level. Key Words: innovation, laptop, computer, biology, science, secondary, implementation, perceptions, instruction, professional development, qualitative, descriptive.
Finite Element Formulations for Lateral Torsional Buckling of Shear Deformable Planar Frames
(University of Ottawa (Canada), 2010) Wu, Liping
Laterally unsupported steel frames commonly occur in industrial structures and pipe racks. In these applications, frames are typically unsupported in the lateral direction at the beam to column junctions, a key difference from typical details in commercial applications. Present design procedures in structural steel standards are not intended for the design of these types of structures. It is thus of interest to develop analysis and design tools for such structures that are reliable, systematic, and simple enough to be implemented in structural analysis software and used in design offices. Towards this goal, this doctoral thesis contributes to two aspects of importance to the lateral torsional buckling analysis of laterally unsupported plane frames: (a) the incorporation of shear deformation effects in the buckling analysis of thin walled members, and (b) the quantification and modelling of partial warping restraints provided by moment connections in typical moment resisting plane frames to adjoining beams and columns. The theory and finite element developed under item (a) deviate from conventional theories in three respects: 1) It is based on general non-orthogonal coordinates, which makes it particularly suited for the effective modeling of members with eccentric supports (i.e., supports that do not coincide with the location of the shear centre; 2) It captures shear deformation effects due to bending and warping; 3) It incorporates the effect of load position relative to the shear centre. A new variational principle for the problem is developed from first principle. The variational principle is used to formulate the governing differential equations for thin-walled members based on the principle of stationary total potential energy. The closed form solutions of the resulting field equations and boundary conditions are developed for the cases of column flexural buckling, column torsional buckling, and lateral torsional buckling of beams under uniform moments, and comparisons to classical solutions were conducted. A finite element is then developed for more general cases of loading schemes and boundary conditions and compared to predictions based on classical solutions and general finite element analysis results undertaken. In all cases examined, the present solution provides buckling resistance predictions lower than those based on the classical solution that do not include the effect of shear deformation. Shear deformation effects are found negligible when predicting buckling resistances for columns of typical geometries, but it can be significant when predicting the buckling resistance of beams under high moment gradients. Towards item (b), a formulation of the partial warping restraint provided by common moment connections to adjoining members is developed based on a shell formulation. The finite element developed is designed to interface with other collinear elements such as that developed under task (a), to accurately and efficiently predict the lateral buckling resistance of moment resisting plane frames. Comparisons between the predictions based on the present formulation and those based on established shell finite element analysis illustrate the ability of the model to efficiently and reliably predict the lateral buckling resistance of laterally unsupported frames.
Domestic Violence in Aboriginal Communities: A Context for Resilience
(University of Ottawa (Canada), 2011) Olsen Harper, Anita
My research is a study of the perspectives of resilience by survivors of domestic violence (DV) in three Aboriginal communities. The Executive Directors (EDs) of the women's shelters on these reserves were interviewed, as well as three DV survivors who were identified by the EDs. The meanings articulated by interviewees is intended to provide educators and those in anti-violence efforts with an increased understanding of resilience as defined by Aboriginal DV survivors. The interpretations that were voiced are different from those that are understood according to prevailing Western tradition. Among Aboriginal populations, internally-derived perspectives of resilience, I contend, are foundational in developing curricula aimed at reducing DV and its traumatic manifestations. DV is often deceptively and simplistically construed as the conduct and dynamics of two people within a home. However, my investigative study that includes a comprehensive literature review, exposes the fallacy of this assumption as it pertains to Aboriginal communities: DV has historic origins that are strongly grounded in colonialism. DV is, as well, socially constructed in power hierarchies that sustain patriarchal supremacy, and a devastating social and psychological plague in all reserve communities. My research recognizes that community-based interventions in Aboriginal communities can only be effectively operationalized with the knowledge of the intricacies of colonialism as they pertain specifically to DV. Drawing on traditional beliefs and community principles such as meaningful participation, integration of cultural and spiritual practices, recognition of historical injustices by colonizing forces, consensus-derived decision-making involving women and youth all help inform educational offerings about the actionable content and delivery of resilience teachings. Keywords: Aboriginal, colonialism, domestic violence, resilience, well-being
Identification of SMYD2 interactions and substrates by immunoprecipitation coupled to mass spectrometry
(University of Ottawa (Canada), 2011) Abu-Farha, Mohamed; Figeys, Daniel,
Very little is known about SMYD2 (SET and MYND containing protein 2), which is a member of the SMYD protein family. However, the interest in better understanding the roles of SMYD2 has grown due to recent reports indicating that SMYD2 methylates p53 and histone H3. I report the cytosolic and nuclear interactome of SMYD2 using a combination of IP-HTMS, ChIP-HTMS and co-immunoprecipitation methods. In particular, I report that SMYD2 interacts with HSP90alpha independently of the SET and MYND domain. The interaction of SMYD2 with HSP90alpha enhances SMYD2 histone methyltransferase activity and specificity for histone H3 at lysine 4 (H3K4) in vitro. Interestingly, histone H3K36 methyltransferase activity is independent of its interaction with HSP90alpha similar to LSD1 dependency on the androgen receptor. I also show that HSP90alpha is methylated by SMYD2 at lysine 209 and 565. Methylation of HSP90alpha is removed by LSD1. We have demonstrated that SMYD2 is being automethylated. Automethylation of SMYD2 is inhibited by the increasing concentration of recombinant SMYD2 in vitro. Even though the function of SMYD2 is still not fully understood, it is clear that it acts as an activator of gene expression as shown by microarray analysis. In this experiment, I have showed using a cDNA microarray that SMYD2 gain of function is correlated with the up-regulation of 37 and down-regulation of 4 genes. The majority of these genes are involved in the cell cycle, chromatin remodeling, and transcriptional regulation. TACC2 is one of the genes up regulated as a result of SMYD2 gain of function. Up-regulation of TACC2 by SMYD2 occurs as a result of SMYD2 binding to the TACC2 promoter where it methylates H3K4. When combined together, the interaction and the gene expression data confirm the suggested role of SMYD2 in DNA damage response.

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