ETDs: Doctoral Theses

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Constructing life narratives: how novels and policy discourses represent and respond to life stories about people with mental disabilities
(Laurentian University of Sudbury, 2011-11-16) McCauley, Karen
This dissertation explores how an interdisciplinary analysis may contribute insight into how literary and policy discourses construct the life experiences of people who have mental disabilities that impair their ability to communicate their own life stories. Chapter One explains why a more comprehensive understanding of the cultural construction of mental disability may be achieved by exploring interdisciplinary relationships between social work, disability studies and literary theory. Subsequent chapters examine theoretical assumptions and frameworks associated with these contributing disciplines in greater detail, across systematic and interpretive analytic approaches. In addition, key concepts and questions relevant to constructing a vocabulary that facilitates collaboration between the contributing disciplines are considered. This literature review informs a methodology for undertaking an interpretive discourse analysis of pertinent policy and novels that depict disability within the context of Ontario's 'Institutional Cycle'. Specifically, the research attempts to answer the following questions: What is the relationship between the representation of mental disability in literary narratives and public policy discourses about mental disability; and, how may an interdisciplinary analysis of literary and policy discourses inform policy planning and the provision of services for people with mental disabilities in Ontario? Chapters 6-8 analyze the literary and policy data across Establishment, Reform and Dismantlement phases of the Institutional Cycle to arrive at a set of findings and recommendations that explain relationships between policy and novels across the phases of the Cycle. Finally, key themes for consideration in policy planning for people with mental disabilities are identified as priorities for action in an emerging 'post-institutional' era, in Ontario.
XRD structural assessment of peridotitic garnet with anomalous REE distribution
(2012-12-01) Ross, Kirk Campbell
This thesis explored, as its major aim, the crystallographic and compositional characteristics of a particular type of peridotitic garnet associated with kimberlite. This garnet has a highly sinusoidal rare-earth element (REE) pattern as its distinguishing feature. Before the main research question could be addressed, a technique had to be developed that enabled the rapid and straight-forward acquisition of a full profile digital X-ray diffractogram from a single sub-milligram crystal fragment. After extensive experimentation and testing, successful development and realization of a method that is capable of producing such data was achieved. The next step of this research project was to empirically investigate and assess the crystal lattice strain model (CLSM) of Blundy and Wood (1994). Careful analyses of the REE present in a suite of clinopyroxenes were compared to the crystal structure data given from the XRD technique outlined above. Clinopyroxene is particularly useful for such an assessment because the radius of the M2 site in this mineral is between the largest and smallest REE, making the distribution of REE particularly sensitive to variation of the M2 site, which in turn is a direct consequence of the overall pyroxene structure. Subsequent to illustrating that XRD data could be collected on such small material and the XRD data and structural data given from the CLSM correlate strongly, peridotitic garnets with sinusoidal REE patters were investigated. The conclusions drawn in the first two contributions – namely that it was possible to collect accurate and precise XRD data from sub-milligram specimens and that the crystal structure and REE distribution were directly related – were imperative for the deduction of conclusions in the final, major research question. The XRD analysis of many garnets with and without sinusoidal REE patterns showed the presence of a small amount of an additional phase in some of these garnets. While this phase (2 out of 3 peaks indexed as possibly orthorhombic perovskite) is not present in sufficient quantities to give rise to such a strong sinusoidal segment in the garnet REE pattern, it prompted the critical step forward in formulating a working hypothesis for the otherwise inexplicable REE patterns. Specifically, I posit that many of the sinusoidal garnets may originally have precipitated as a very high pressure phase (in the mantle transition zone or deeper) that subsequently underwent a subsolidus isochemical transformation to garnet. Possible original precursor mineralogy is a combination of two perovskites or a perovskite + iv garnet assemblage. Theoretical calculation using experimental partition coefficients demonstrated that a mixture of Ca-perovskite (CaPv) and Mg-perovskite (MgPv) REE patterns in the approximate proportions of 10% CaPv and 90% MgPv produce a REE diagram that is strikingly similar to those observed in sinusoidal single phase garnet. It has been shown experimentally that with increasing depth in the mantle, garnet plus a progressively increasing CaPv component is the stable mineral assemblage. Initial precipitation of two perovskites or CaPv + garnet as cumulates from a deep magma ocean would preserve the REE distribution of these minerals. Subsequent exhumation of such an assemblage would result in the retrogressive subsolidus phase transformation to a mineral stable at conditions of T and P of the shallow mantle environment, i.e. garnet, while retaining the REE pattern of the initial precipitate mineral assemblage. While this working hypothesis will require many more tests, its proposal may have significant implications for the mantle structure.
Compétences linguistiques et cognitives des enfants bilingues en situation linguistique minoritaire
(Laurentian University of Sudbury, 2013-07-30) Mayer-Crittenden, Chantal E.
Au Canada, l’évaluation langagière des enfants franco-ontariens s’avère une tâche complexe pour les orthophonistes en raison d’une carence d’outils et de normes régionales. Le problème s’accentue lors de l’évaluation langagière des enfants bilingues (anglais-français) qui fréquentent des écoles de langue française. L’étude que nous proposons ici a d’abord réitéré auprès de 26 enfants francoontariens une recherche québécoise (Thordardottir et coll., 2010) dans laquelle on a évalué la performance d’enfants franco-québécois avec une batterie de tests qui sert à mesurer les compétences linguistique et cognitive. Ces enfants ont été répartis en trois groupes d’âge : 4;6, 5;0 et 5;6 ans. Notre étude a ensuite évalué la performance d’enfants bilingues (47 français-anglais et 31 anglais-français) du même âge sur cette même batterie de tests à laquelle elle a ajouté un ensemble de tests de langue anglaise. Les enfants ont été appariés selon l’âge, le statut socio-économique et la cognition non verbale ; ils différaient selon la quantité d’intrants (input) dans chaque langue et selon le statut linguistique des langues (minoritaire/majoritaire). Les trois groupes linguistiques ont été créés selon le niveau d’exposition aux langues ; nous avons ainsi distingué les monolingues, les franco-dominants et les anglo-dominants. En outre, des enfants identifiés par les orthophonistes scolaires comme ayant un trouble primaire du langage (n = 20) ont été évalués à l’aide des mêmes tests afin de confirmer ou d’infirmer la présence de trouble primaire du langage. En outre, a été examiné l’effet de l’intrant langagier dans l’acquisition d’une langue minoritaire, puisque cet apprentissage a lieu au contact d’une langue majoritaire qui, au demeurant, exerce son influence aussi sur les enfants monolingues (francophones) et bilingues (français-anglais et anglais-français). Les résultats montrent que, au plan linguistique, les Franco-Ontariens monolingues réussissent moins bien que les Franco-Québécois. Les franco-dominants réussissent encore moins bien que les monolingues et les anglo-dominants réussissent moins bien que les monolingues et les franco-dominants à l’âge de 4;6 ans et de 5;0, mais cela n’est pas toujours le cas pour les enfants anglo-dominants de 5;6 ans. En fait, pour certaines épreuves de langue française, les anglo-dominants obtiennent des scores supérieurs à ceux des monolingues et des franco-dominants. Les résultats montrent aussi que plus l’anglo-dominant reçoit d’intrants en français à l’école, meilleure est sa performance linguistique en français. Chez les franco-dominants, c’est l’inverse qui se produit puisque plus l’enfant vieillit, plus il reçoit d’intrants en anglais. Les résultats ont aussi montré que, parmi les 20 cas de trouble primaire du langage, 16 ont été confirmés. Somme toute, ces résultats témoignent de la différence importante entre les Franco- Québécois et les Franco-Ontariens, de sorte que l’emploi des normes québécoises pour les Franco-Ontariens est remis en question. De plus, l’effet de l’intrant est accentué chez les groupes bilingues, ce qui met en évidence le rôle incontestable de l’intrant langagier et aussi celui du statut des langues lors de l’acquisition d’une langue seconde.
Économie informelle et analyse relationnelle
(Laurentian University of Sudbury, 2013-07-30) Kabatakaka, Bululu
Cette thèse de doctorat a pour objet la connaissance du processus de formation d’une culture de l’économie informelle et sa reproduction chez l’élite dans les pays en développement. Son questionnement de base est : comment étudier l’économie informelle dans les pays en développement dans une perspective relationnelle ? Elle a mis à profit la complémentarité des connaissances de l’économie et de la sociologie dans la compréhension des dimensions rationnelles et non rationnelles des comportements et attitudes de l’élite dans les pays en développement face à cette économie. Nous avons considéré les fonctionnaires comme indicateurs de l’élite. Cette thèse apporte deux contributions majeures 1) l’élargissement du modèle Laflamme et de l’analyse compréhensive de Weber grâce à l’opérationnalisation du concept de socialisation et 2) l’identification de quelques éléments porteurs de l’économie informelle sur lesquels il faut asseoir la dynamique de la réduction de la pauvreté. Cette contribution doit être inscrite dans les limites géographiques de l’étude. L’application de la méthodologie dans d’autres villes du pays et dans d’autres capitales des pays en développement permettrait d’en vérifier la généralisation.
Caractéristiques et logiques des musiques populaires
(Laurentian University of Sudbury, 2013-07-31) Lemieux, Suzanne
L’objet de notre thèse de doctorat concerne les caractéristiques et les logiques des musiques populaires. D’une façon générale, nous nous demandons : quelles sont les logiques qui déterminent le thème de l’oeuvre dans la musique populaire ? Quelles caractéristiques découlent de ces logiques ? Les ouvrages recensés ont été classés dans trois ensembles selon que les musiques populaires sont définies comme standard, comme standard et originales ou comme hétérogènes. La thèse veut vérifier laquelle de ces tendances (standard, standard/originale, hétérogène) explique le mieux l’oeuvre de musique populaire. Pour y parvenir, la recherche d’une explication des oeuvres de musique populaire a dû passer par une opérationnalisation et une vérification empirique des oeuvres de musique populaire. Les hypothèses spécifiques liées aux thèses standard, standard/originale et hétérogène, ainsi qu’une hypothèse générale permettant une articulation entre ces trois thèses ont été soumises aux résultats de notre analyse qui a porté sur 110 chansons à succès canadiennes-françaises et françaises qui appartiennent à la période qui va de 1995 à 2005. Les résultats montrent que l’hypothèse des hétérogénistes est grandement confirmée. Cependant, nos analyses ont repéré des données marginales qui vont dans le sens des attentes des standardistes et des dualistes. Pour dépeindre l’ensemble des musiques populaires, nous proposons une nouvelle hypothèse hétérogène, inclusive de ces quelques représentations standard que nous avançons sous le concept de « tendance hétérogène ».
La programmation des contenus des aides à la communication avec sortie vocale chez les jeunes enfants qui ont des besoins complexes en communication
(Laurentian University of Sudbury, 2013-07-31) Robillard, Manon
La présente thèse a pour objectif la découverte de pistes pour faciliter la sélection de l’aide à la communication avec sortie vocale (ACSV) et la programmation de son vocabulaire pour les jeunes enfants âgés de 4 à 6 ans qui ont des besoins complexes en communication (BCC). Cette étude a premièrement examiné le vocabulaire de base qui doit être programmé dans les ACSV des jeunes enfants francophones et bilingues qui vivent en situation minoritaire. Cinquante-sept enfants qui fréquentent une école de langue française ont participé aux enregistrements libres en salle de classe. L’analyse du corpus a révélé que 216 mots représentent 80,15% du vocabulaire utilisé par les enfants francophones de la maternelle et du jardin. L’analyse du corpus des enfants bilingues et des enfants qui ont un trouble du langage a donné des résultats comparables. Une seule liste de 200 mots a été produite en combinant le vocabulaire à fréquence et similitude élevée de trois groupes : les francophones, les bilingues et un ensemble d’enfants présentant des troubles du langage. Ces mots devraient être programmés dans les ACSV des jeunes enfants francophones et bilingues qui fréquentent une école de lange française dans un milieu minoritaire, quelle que soit leur habileté linguistique. Ces nombres sont semblables à ceux des études qui ont été effectuées en anglais aux États-Unis et en Australie, sauf que les mots ne sont pas les mêmes. D’ailleurs, seulement 61,50 % des mots de base de notre étude se trouvent sur la liste anglaise la plus récente. Une traduction n’aurait donc pas suffi et, dans cette perspective, notre étude s’avère importante. En outre, seulement 44,50 % des mots de base de notre étude se trouvent sur la liste de sélection de vocabulaire présentement utilisée chez la population francophone au Nord de l’Ontario. L’impact des facteurs cognitifs et linguistiques sur la navigation dans les ACSV a ensuite été analysé. Soixante-cinq enfants âgés de 48 à 77 mois ont participé aux évaluations cognitives, linguistiques et à une épreuve de navigation à l’aide du iPad2™. Bien que des corrélations significatives aient été trouvées entre la navigation et plusieurs facteurs cognitifs et linguistiques, il appert, en fin de compte, que le sous-ensemble pragmatique de facteurs permettant le mieux de prédire la capacité de navigation chez les jeunes enfants inclut l’attention, la catégorisation et le raisonnement. Lors de l’évaluation en suppléance à la communication (SC), les compétences d’attention, de catégorisation et de raisonnement devraient être prises en considération afin de mieux assurer la bonne sélection de l’ACSV. Les résultats de cette étude permettent d’établir les mots nécessaires lors de la programmation des ACSV pour les jeunes enfants francophones et bilingues en milieu minoritaire, et ils suggèrent que trois sous-tests du Leiter-R pourraient être utilisés pour déterminer l’habileté de naviguer dans une ACSV qui a une pagination dynamique.
Evolution and ecology of an amphibian emerging infectious disease: a context-dependant approach of ranavirus virulence in Lithobates (Rana) pipiens
(Laurentian University of Sudbury, 2013-07-31) Echaubard, Pierre
Host-pathogen investigations have conceptually evolved during the last two decades, from a basic and descriptive approach to a current hypothesis-driven and a more theoretical discipline shaped by evolutionary biology. Our deeper understanding of the elements influencing the mutual selective pressures that the host and the pathogens exert on each other, together with recent conceptual advances, currently position this field of research at the frontier between ecology and evolution. Recent theoretical considerations define hostpathogens systems as an evo-eco mosaic comprised of evolutionary and ecological attributes in turn underlying the context-dependent nature of the system dynamic. Therefore, investigations of host-pathogen interactions should integrate the diversity of the systems drivers by using an integrative approach in order to elucidate both coevolutionary trajectory and epidemiological dynamic of the system. In this thesis, such a framework is used to investigate Amphibian/ranavirus interactions. Ranaviruses are emerging pathogens known to have caused amphibian die-offs on five continents with the greatest number of reported mortality events documented in North America and Europe. Despite an increasing understanding of ranaviral disease properties, ranavirus disease dynamics in the environment remain poorly understood. For instance, the influence of potential abiotic and biotic mechanisms including temperature, local landscape features, larval developmental stages, host density and genetic variability as well as genotypic interactions between the host and the pathogen has on the prevalence and virulence of the virus remains to be elucidated. In order to improve our knowledge regarding these specific determinants of ranaviral disease, I designed a combination of manipulative laboratory experiments and a field mensurative survey using the ranid amphibian Lithobates (Rana) pipiens as the host model for this system. I observed that populations of amphibian hosts inhabiting urbanized landscapes suffered from significant decline in genetic diversity in turn promoting the accrued infection by the ranavirus (manuscript 1). Complementary analysis using two amphibian host species, L.pipiens and L.sylvaticus, and three ranavirus strains revealed significant variation among hosts for their susceptibility to ranavirus, and significant variation among ranavirus strains for infectivity. I also showed that specific amphibian/ranavirus interactions might have a tighter coevolutionary history than other combinations, resulting in sharper mutual coadaptations and the potential for frequency-dependent selection to operate in this system. However, the coevolutionary trajectories in this host-pathogen system are dependent on the temperature conditions in which the interaction takes place. Amphibian/ranavirus interactions outcomes iv are therefore temperature, host, and pathogen genotype-dependent suggesting that the range of infection outcomes in this system is potentially large (manuscript 2). Further, I observed that increasing animal holding density is detrimental for host fitness as mortality rate is higher, day of death earlier, development longer, and growth rate significantly lower when tadpoles are experimentally exposed to ranavirus in high holding density situations. These results paralleled a linear increase of detrimental effects when ranavirus doses increased in low density conditions, with control tadpoles having a significantly higher overall relative fitness. However, this pattern was not observed in high density conditions, where the effects of increasing ranavirus dose were limited, revealing non-trivial density-dependence of virulence expression (manuscript 3). Finally, ranavirus infection rate varied with the host developmental stage as the host immune system clears the infection over the course of individual host development. However the intensity of the clearing depends on both the timing and number of ranavirus exposures (manuscript 4). Overall the results described in my thesis suggest that ranavirus virulence depends on a diversity of ecological, epidemiological, and evolutionary determinants. The underlying complexity of ranavirus
Adaptation during a longitudinal integrated clerkship: the lived experiences of third-year medical students at the Northern Ontario School of Medicine.
(Laurentian University of Sudbury, 2013-07-31) Dubé, Tim V.
There are three interrelated concepts of what medical students learn, which include the formal, informal, and hidden curriculum. Several researchers who have investigated notions of the hidden curriculum have demonstrated how the experiences of medical training entrenched in the hidden curriculum can have a profound impact on medical student adaptation. The most influential transitional stage in undergraduate medical education is the third-year clinical clerkship, when medical students transition from classroom learners into clinicians. The Northern Ontario School of Medicine’s (NOSM) clinical clerkship year consists of a mandatory eightmonths of living and working in rural and northern communities throughout Northern Ontario, and learning in the context of rural family practice. Informed by a social constructivist research paradigm, I explored how 12 third-year students described the challenges they had to manage and, in response, the strategies they employed to adapt to their clerkship. I elicited their experiences and perspectives to contribute to a rich understanding of how students at the NOSM describe developing processes of adaptation during the Comprehensive Community Clerkship. Data were collected between August 2011 and April 2012, including: a) pre-clerkship interviews and a demographic questionnaire, b) mobile methods in the form of ‘guided walks’ in the communities, and c) post-clerkship interviews. The quality of the data collection and analysis were enhanced through processes of methodological and interpretive rigour, representativeness and authenticity, rich description and contextual relevance, audit trail, and reflexivity. Through an inductive thematic analysis of the data, the findings provide a rich description of events experienced such as medical training in one’s hometown or a familiar community, iv transitions including adaptation to the clinical setting and to the medical profession, and the influence of the clerkship on career path, personal well-being, and empathy for patients. The findings serve to advance our understanding of how medical students describe developing processes of adaptation throughout a longitudinal integrated clerkship. Implications are considered for medical students, the NOSM, the clerkship communities, and medical schools nationally and internationally. I propose recommendations regarding the suitability of authentic methods in medical education research, and discuss the implications for rural and northern health research.
The black sun of boredom: Henri Lefebvre and the critique of everyday life
(Laurentian University of Sudbury, 2013-07-31) Gamsby, Patrick
This dissertation examines how boredom can be understood in the context of Henri Lefebvre’s (1901-1991) critique of everyday life. Through an integration of the boredom literature, both the fully developed studies as well as fragmentary passages, I argue that Lefebvre’s critique of everyday life adds an important dimension to understanding boredom in modernity. One of the leading strands in boredom studies today argues that boredom is an historically specific experience unique to the rhythms of life imparted with the onset of modernity. Viewed in this light, boredom is a relatively recent phenomenon that can be linked to what Lefebvre calls the ‘double process’ of industrialization and urbanization. Although the mass profusion of boredom has left a seemingly indelible mark on society, it has received relatively little attention in both everyday life and academia. First coined in the middle of the 19th century, boredom is a relatively new word for what today is an all too pervasive experience. Writing throughout most of the 20th century, Lefebvre makes numerous references to boredom, yet, despite claiming that a study of boredom would be a significant contribution to his critique of everyday life, he never developed an in-depth and sustained analysis of this experience. Lefebvre did, however, identify an internal dialectic of mass culture as being an integral component for understanding boredom. It is argued that Lefebvre’s theory of a dialectical process inherent to mass culture is a key for understanding boredom as an historically specific phenomenon. In organizing this dissertation, a constellation of themes are presented in order to articulate this dialectic. After exploring boredom’s relationship to modernity, I then discuss what Lefebvre considers as the verso of modernity, everyday life. Following this, I consider the contradictions of space that give rise to boredom in urban centres and suburban peripheries by critically analyzing both the production of those spaces as well as how they are consumed in everyday life. Finally, I consider the escape from boredom offered in select sounds and images of the culture industry and its opposite, the embrace of boredom in certain 20th century avant-garde art movements. Through a reading of Lefebvre’s critique of everyday life and complementary texts, this interdisciplinary dissertation is a contribution to understanding the mass phenomenon of boredom in modernity.
Environmental attitudes of homeschoolers in Canada
(Laurentian University of Sudbury, 2013-07-31) McMillan, Emily Elizabeth
Environmental attitudes are shaped by a variety of factors including our educational history, cultural background, childhood and life experiences, and past and current interactions with nature. This research set out to examine attitudes toward the environment in an understudied but growing segment of the Canadian population, homeschoolers. The purposes of this study were to investigate whether environmental attitudes in Canadian homeschoolers differ from those of people involved with public school and to acquire a greater understanding of the factors that affect the development of these attitudes. The mixed method, follow-up explanatory research design utilized the New Ecological Paradigm Scale and the Connectedness to Nature Scale in an internet survey. The survey was sent to homeschooling and parent groups across Canada. Subsequently, interviews were conducted with a subsample of respondents. The results of the survey showed that demographic variables were not significantly related to environmental attitude scores with the exception of locale and religion. Urban respondents had slightly stronger environmental attitudes than rural respondents. The confluence of homeschooling and religiosity emerged as the key factor influencing environmental attitudes. There was no significant difference between environmental attitudes of homeschoolers and public schoolers until importance of religion was taken into account. As measured by the scales, religious homeschoolers exhibited the weakest environmental attitudes, public schoolers were in the middle, and not-as-religious homeschoolers had the strongest environmental attitudes. The qualitative data supported these results, with religious homeschoolers expressing weaker iv environmental attitudes, particularly in terms of climate change and the need for a more sustainable lifestyle. Religious homeschooling respondents favoured a more structured back to basics style of schooling which also correlated with lower environmental attitude scores. Unstructured homeschooling respondents tended to choose a child-centred philosophy of education which was correlated with stronger environmental attitudes. During the interviews, respondents were asked to reflect on what in their lives had influenced their attitudes toward the environment. Consistent with other literature, unstructured outdoor time as a child remained the most significant factor, cited by a majority of respondents. Other important factors included religion, parents, school, teachers, TV/media, economic necessity, and negative experiences with environmental pollution. The results of this study highlight the importance of considering variables associated with religion when exploring the development or level of environmental attitudes or when conducting a study of homeschooling. Religious beliefs are complex and highly personal in some cases, as is their corresponding influence on environmental concern. Potential exists for environmental concern and action from a group of spiritual people with strong community bonds and often political involvement. The key may be finding common ground and learning to communicate, while resisting expectations of complete agreement. This dissertation showed that stepping outside of the educational system does not necessarily have a direct impact on environmental attitudes, as they are mediated by a complex array of variables. Homeschooling may not directly generate a different level of environmental attitudes than public school; however, religious v homeschoolers definitely have a different set of attitudes toward the environment that deserve further in-depth study.
From saboteurs to allies: the role of children and youth in teacher candidates’ development of classroom management
(Laurentian University of Sudbury, 2013-07-31) Danyluk, Patricia Jill
How do children and youth in the classroom impact on the development of student teachers’ classroom management skills during the teaching practicum? This study approached the problem through the sociology of childhood/youth, using a human development framework, and asked children and youth what role they believe they play in the formation of classroom management skills for teaching candidates. Utilizing a phenomenological method, this study sought to discover the perspectives of children and youth, and student teachers themselves, as classroom management developed. Until now, the role that children and youth play in the development of classroom management for student teachers has largely been ignored. Through a series of observations, focus groups, student teacher questionnaires, and narratives, a portrait emerged of children and youth as active agents in the development of student teachers’ classroom management skills. The key findings indicate that children and youth utilize their agentic status to communicate their needs to student teachers verbally, physically, and through behaviour. A new model of student teaching emerged, suggesting a teaching quadrad where children and youth in the classroom are recognized as playing a role equal to or more significant than that of associate teachers or faculty in the development of classroom management for student teachers.
Étude normative sur le développement de la parole et du langage chez l'enfant franco-ontarien : normalisation et validation du Profil de la langue, du langage et de la parole (PLLP)
(Laurentian University of Sudbury, 2013-09-12) Minor-Corriveau, Michèle
Pulsed electron deposition and characterization of nanocrystalline diamond thin films
(Laurentian University of Sudbury, 2013-10-07) Alshekhli, Omar
Diamond is widely known for its extraordinary properties, such as high hardness, thermal conductivity, electron mobility, energy bandgap and durability making it a very attractive material for many applications. Synthetic diamonds retain most of the attractive properties of natural diamond. Among the types of synthetic diamonds, nanocrystalline diamond (NCD) is being developed for electrical, tribological, optical, and biomedical applications. In this research work, NCD films were grown by the pulsed electron beam ablation (PEBA) method at different process conditions such as accelerating voltage, pulse repetition rate, substrate material and temperature. PEBA is a relatively novel deposition technique, which has been developed to provide researchers with a new means of producing films of equal or better quality than more conventional methods such as Pulsed Laser Deposition, Sputtering, and Cathodic Vacuum Arc. The deposition process parameters have been defined by estimating the temperature and pressure of the plasma particles upon impact with the substrates, and comparing the data with the carbon phase diagram. Film thickness was measured by visible reflectance spectroscopy technique and was in the range of 40 – 230 nm. The nature of chemical bonding, namely, the ratio (sp3/sp3+sp2) and nanocrystallinity percentage were estimated using visible Raman spectroscopy technique. The films prepared from the ablation of a highly ordered pyrolytic graphite (HOPG) target on different substrates consisted mainly of nanocrystalline diamond material in association with a diamond-like carbon phase. The micro-structural properties and surface morphology of the films were studied by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The mechanical properties of the NCD films were evaluated by nano-indentation.
Regional volcanogenic massive sulphide metallogeny of the neoarchean greenstone belt assemblages on the northwest margin of the Wawa subprovince, Superior province
(Laurentian University of Sudbury, 2013-10-08) Lodge, Robert Wilfred David
The ca. 2720 Ma Vermilion, Shebandowan, Winston Lake, and Manitouwadge greenstone belts (VGB, SGB, WGB, and MGB, respectively) are located along the northern margin of the Wawa subprovince. They are interpreted to have formed in broadly similar rifted arc to back-arc environments, but their base and precious endowment and, in particular, their endowment in VMS deposits, differ markedly. These difference is metal endowment reflect differences in their metallogenic history that were examined by comparing their regional, belt-scale lithostratigraphy, chemostratigraphy, petrogenesis and tectonic history constrained by new U-Pb zircon geochronology. The MGB is the most VMS-endowed and isotopically juvenile (Pb and Nd) greenstone belt. It has a trace element chemostratigraphy that is consistent with a rifted arc to back-arc environment. The trace element chemostratigraphy of the WGB is also consistent with a rifted-arc to back arc geodynamic setting. The Winston Lake VMS deposits formed during early rifting of the arc and their timing is tightly constrained at ca. 2720 Ma by U-Pb ages of the host felsic strata and post-VMS Zenith gabbro. The Zn-dominated VMS mineralization formed from hydrothermal fluids that were <300 ° and were possibly boiling in relatively shallow water. The trace element chemostratigraphy of the VGB, SGB, and WGB indicates a plume-driven rifted arc to back-arc geodynamic settings. The composition of VMS mineralization, lithofacies, and alteration in these belts are consistent with a relatively shallower-water environment, which may have compromised VMS formation. The high-Mg andesites that are typical of, but restricted to, the SGB formed during compressional “hot” subduction, which resulted in the development of a thicker arc crust. This thicker crust may have inhibited VMS formation, but favoured the formation of magmatic sulphide and gold mineralization. New detrital and magmatic zircon U-Pb geochronology allowed comparison and correlation of lithostratigraphy and metallogeny between the greenstone belts. U-Pb ages within the VGB also defined younger, Timiskaming-type volcanic and sedimentary strata that are coeval with similar deposits in the SGB. These strata are spatially and temporally associated with gold mineralization in both belts and are coeval with similar deformation and magmatic events in the WGB and along the northern margin of the Wawa-Abitibi terrane. This indicates that the formation of Timiskaming-type pull apart basins in the northern part of the Wawa-Abitibi terrane were synchronous, and earlier than in the southern part, which is consistent with oblique convergence of the Wawa-Abitibi terrane onto the Superior Province. Detrital zircon geochronology also revealed the presence of a >2720 Ma iv zircon population within the Timiskaming-type sedimentary strata of the SGB. This is consistent with their derivation from the Wabigoon subprovince and suggests trans-terrane transport of detritus in a foreland –type basin resulting from uplift of the Wabigoon subprovince during accretion of the Wawa subprovince.
Thesis
(Laurentian University of Sudbury, 2013-10-09) Behdin, Nowrouzi
Nursing is a stressful occupation with various physical and psychosocial stressors inherent in its practice. While the physical stressors of nursing are generally understood, less understood are the psychological and social stressors of the profession. With the many changes in healthcare facilities and structures that are occurring today and, in turn, affecting nurses, it is increasingly important to better understand the psychosocial stress experiences of nurses. Grounded in the Job Demand-Control-Support Framework, the objectives of this study were to: 1) examine factors associated with quality of work life (QWL) of Registered Nurses working in four small urban hospital-based obstetric programs, 2) determine if nursing occupational stress, QWL, and various factors (e.g., demographic, locations with and without cross-training) are associated with nurses’ work ability, where work ability is the worker’s capacity to perform their work, as was measured by the work ability index, and 3) review and evaluate some workplace interventions targeting occupational stress management and burnout for nurses.
Prématurité, langue et pronostics neurodéveloppement mentaux chez l’enfant premature Nord-Ontarien
(Laurentian University of Sudbury, 2013-11-07) Bélanger, Roxanne
Le taux de survie des nourrissons prématurés s’est amélioré de façon manifeste grâce à la formation des soignants, à la régionalisation des soins prodigués au nourrisson prématuré et à une amélioration de la technologie disponible aux professionnels de la santé. Malheureusement, malgré ces avancées, on a observé peu de changement correspondant au taux de morbidité néonatale. Le suivi neurodéveloppemental est un domaine de recherche important, surtout à la lumière de nouvelles preuves qui indiquent que, jusqu’à l’âge de 6 ans, la croissance de la période prénatale est rapide, dramatique, et permet de façonner les suivis à long terme de l’enfant. Dans ce domaine, aucune étude ne porte sur le développement de l’enfant prématuré nord-ontarien. De plus, cette population est particulière parce qu’une proportion significative est exposée à un environnement bilingue dans un contexte linguistique minoritaire. Cette étude vise à 1) décrire les enfants nés prématurément et évalués par le Programme de suivi (PS) à l’hôpital Horizon Santé-Nord; 2) comparer les résultats neurodéveloppementaux en langage des francophones aux anglophones et 3) vérifier si certains facteurs biomédicaux et sociodémographiques permettent de distinguer les enfants prématurés affichant un retard neurodéveloppemental des enfants prématurés qui se développent de façon typique.
Structural controls of Ni-Cu PGE ores and mobilization of metals at the Garson Mine, Sudbury
(Laurentian University of Sudbury, 2014-01-24) Mukwakwami, Joshua
The Garson Ni-Cu-PGE deposit is located on the South Range of the 1850 Ma Sudbury structure along the contact between the Sudbury Igneous Complex (SIC) and the underlying metasedimentary and metavolcanic rocks of the Paleoproterozoic Huronian Supergroup. It comprises four ore bodies that are hosted by E-W-trending shear zones that dip steeply to the south. The shear zones formed as south-directed D1 thrusts in response to flexural-slip during regional buckling of the SIC. They imbricated the ore zones, the SIC norite, the underlying Huronian rocks and they emplaced slivers of Huronian rocks and anatectic breccia into the overlying Main Mass norite. Coexisting garnet-amphibole pairs yielded syn-D1 amphibolite facies metamorphic temperatures ranging from ~550°C to 590°C. The shear zones were coeval with the moderately southdipping South Range and Thayer Lindsley shear zones, which formed to accommodate the strain in the hinge zone as the SIC tightened with progressive D1 shortening. The SE limb of the SIC was overturned together with the D1 thrusts, which were then reactivated as steeply south-dipping reverse shear zones during syn-D2 greenschist metamorphism.Syn-D2 metamorphic titanite yield a U-Pb age of ca. 1849 ± 6 Ma, suggesting that D1 and D2 are part of a single progressive deformation event that occurred immediately after crystallization of the SIC during the Penokean Orogeny. The ore bodies plunge steeply to the south parallel to the colinear L1 and L2 stretching mineral lineations. Ore types consist mainly of pyrrhotite-pentlandite-chalcopyrite breccia ores, but also include pyrrhotite-pentlandite-chalcopyrite disseminated sulfide mineralization in norite, and syn-D2 quartz-calcite-chalcopyrite-pyrrhotite-pentlandite iv veins. In the breccia ores, matrix sulfides surround silicate rock fragments that have a strong shape-preferred orientation defining a pervasive foliation. The fragments are highly stretched parallel to the mineral lineations in wall rocks, suggesting that the ore bodies are zones of high strain. Pyrrhotite and chalcopyrite occur in piercement structures, in boudin necks between fragments, in fractures in wall rocks and in fold hinges, suggesting that the sulfides were mobilized by ductile plastic flow. Despite evidence of high strain in the ore zones, the sulfide matrix in D1 and D2 breccia ores show little evidence of strain as they consist predominantly of polygonal pyrrhotite aggregates, suggesting that they recrystallized during, or immediately after D1 and D2. However, rare elongate pyrrhotite grains aligned parallel to S2 are locally preserved only in D2 breccia ores. Exsolution of pentlandite loops along grain boundaries of elongate pyrrhotite formed S2-parallel pentlandite-rich layers in D2 breccia ores, whereas the pentlandite loops are multi-oriented in D1 contact breccia as they were exsolved along grain boundaries polygonal pyrrhotite. Because exsolution of pentlandite post-date D1 and D2, and that individual pentlandite grains neither have a shape-preferred orientation nor show evidence for cataclastic flow, the sulfides reverted to, and were mobilized as a homogeneous metamorphic monosulfide solid solution (mss) during D1 and possibly D2. This is in agreement with predictions from phase equilibria as the average Garson composition plots within the mss field in Fe-Ni-S ternary diagram at temperatures above ~400°C. Disseminated and breccia ores at Garson have similar mantle-normalized multi-element chalcophile patterns as undeformed contact-type disseminated and massive ore, v respectively, at the well known Creighton mine in the South Range. This suggests that the Garson ores are magmatic in origin and that their compositions were not significantly altered by hydrothermal fluids and deformation. The lack of variations in Ni tenors between the disseminated and breccias ores suggest that the R-factor was not the process controlling metal tenors because the disseminated sulfides do not consistently have higher metal tenors than the breccia ore. The breccia ores are enriched in Rh-Ru-Ir and are depleted in Cu-Pd-Pt-Au, in contrast to footwall-type ore at the nearby Garson Ramp mine which is enriched in the same metals. When Ni100, Rh100, Ir100, Pt100 and Pd100 are plotted against Cu100, the breccia and footwall-type ore analyses plot along model mss fractionation and sulfide melt model curves, suggesting that these two ore types are related by mss fractionation. In summary, the Garson breccia ores are mss cumulates that settled quickly at the base of the SIC via a gravity filtration process, and were mobilized as a metamorphic mss by ductile plastic flow during D1 and D2. Despite minor local hydrothermal mobilization of some metals, the study confirms findings from other studies that highly deformed Ni-Cu-PGE deposits, such as the Garson deposit, can provide important information on the genesis of the deposits.
Stress episodes and adaptation in the National Hockey League according to Canadian professional hockey players from Ontario
(Laurentian University of Sudbury, 2014-03-17) Battochio, Randy Cesar
Adaptation in professional sport is the professional athlete’s capacity to act and react effectively to destabilizing stress episodes so that an internal sense of emotional and psychological balance is restored (Schinke, Tenenbaum, Lidor & Battochio, 2010). Professional ice-hockey players must overcome numerous stressors throughout their careers in the National Hockey League (NHL). Though sport researchers have conducted preliminary studies about the stress and adaptation processes of NHL players, small participant numbers and the use of a structured interview guide limited to rookie and veteran career stages limit the conclusions. Based on these limitations, the purpose of the present dissertation was to provide a comprehensive depiction of the stress episodes and processes that lead to adaptation and maladaptation in the NHL. Twenty-three current and former NHL players were recruited for individual interviews, which were then analysed using Braun and Clarke’s (2006) inductive thematic analysis. As a result, stress episodes and the subsequent strategies attempted to reach adaptation or maladaptation could be housed either within a career stage or across an NHL player’s career. Career stages were (a) entry into the NHL, (b) remaining in the NHL, and (c) becoming an All-Star. Across-career stress involved (a) high profile team, (b) injury, and (c) relocation. Subsequently, the participants identified pathways designed to alleviate or manage the stressors situated within each stress episode. Through retrospection, the participants decided whether their pathways taken during various stress episodes were adaptive. Recommendations were then proposed by these athletes for aspiring NHL players or maladaptive. Implications for sport researchers and practitioners (e.g., coaches, mental performance consultants) are also provided within the conclusion.
Ultraweak photon emission in cells: coupling to molecular pathways, applied magnetic fields, and potential non-locality
(Laurentian University of Sudbury, 2014-03-19) Dotta, Blake
The possibilities and implications of photons within the infrared, visible, and ultraviolet behaving as sources of intracellular and intercellular communication and information were investigated experimentally for melanoma cells during the 24 hrs following removal from incubation. Specific wavelengths during different intervals were associated with specific classes of biomolecules that were predicted based on the physical properties associated with their amino acid sequences. Application of a specific intensity and physiologically patterned magnetic field predicted from a model that applied the concept of magnetic moment to the whole cell resulted in photon emissions. They were detected at distances sufficient to allow intercellular communication. The occurrence of macroscopic entanglement or non-locality was shown between two loci of where simple chemically-based photons emissions were generated. Within all three experiments there was marked quantitative congruence between the energies associated with the power density of the photon emissions and the physicochemical variables involved with their reduction. These results indicate that photon emissions coupled with classic biomolecular pathways and processes may behave as intra- and inter-cellular sources of information that could control the complex dynamics of cells. The effect may not depend upon locality but exhibit non-local characteristics.
Genetic variation and population genetic structure of muskrat, Ondatra Zibethicus, at different spatial scales
(Laurentian University of Sudbury, 2014-03-19) Laurence, Sophie
Understanding the factors and processes that influence intraspecific genetic variation are essential to better understand evolutionary processes. In this research, I examined patterns of gene flow and their effects on the distribution of genetic variation and spatial genetic structuring at different spatial scales. I used a combination of population genetics, spatial analysis, morphometrics and phylogeography in order to understand the patterns of genetic variation and their resulting phenotypic variations in a semi-aquatic species, the muskrat (Ondatra zibethicus).

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