ETDs: Master's Theses

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Legacy planning for major multi-sport events vs faith, hope and charity!
(Laurentian University of Sudbury, 2011-11-21) MacAdam, L. Lane
Not unlike many nations that have bid for and hosted major multi-sport events, franchise holders and their backers in countries around the world routinely cite a number of benefits that will accrue to their country in order to garner the public and private support required to successfully bid for and stage international level major multi-sport events. These benefits include: sport development; social, cultural, economic and community benefits, among others, derived from hosting international level sport events. Canada has an enviable record of hosting major multi-sport events. We have staged them often and we have hosted them well. Since 1967, Canada has hosted almost every major multi-sport event available to it. Billions of dollars in public expenditures have been made in support of these events from all levels of government. But do the promises that are made to convince governments, community leaders and the general public deliver the benefits that they advertise? This research paper will examine the legacy aspects of major multi-sport games from the vantage point of community development, economic impact and in particular sport benefits. It also offers a conceptual framework to evaluate the sport benefit legacies and introduces the Major Event Return Legacy Index (MERLIN©). The prospect of hosting a major multi-sport event attracts a multitude of eager bidders in pursuit of tangible and intangible legacies for a nation. However, the rising complexity and spiraling expenditures necessary to secure, plan and stage these events require more robust assessment tools to properly measure the cost/benefit of supporting these mega projects. This research paper will contribute to the body of knowledge available to assist franchise holders and policy makers in determining the true legacy benefits that can be derived from hosting a major multi-sport event instead of relying on faith, hope and charity!
Colonizing Northern Landscapes: Population Genetics and Phylogeography of Wood Frogs (Lithobates Sylvaticus) in the James Bay
(Laurentian University of Sudbury, 2012-08-31) D'Aoust-Messier, Andrée-Michelle
The genetic structuring of populations can be influenced by present processes and past events. One of the largest historical events to affect the distribution and genetic characteristics of present-day North American biota is the Pleistocene glaciation. Thus, the study of post-glacial colonization patterns of species in northern landscapes can relay important ecological information, as species had to expand their range extensively following the retreat of the glaciers and are often at the terminal end of their expansion. These species consequently exhibit the genetic fingerprints of sequential founder events, in turn decreasing the genetic variation available for adaptation. Using amphibians to investigate post-glacial range expansion is advantageous, as they have limited dispersal abilities revealing fine-scale patterns and they are thought to be one of the first vertebrates to colonize post-glacial habitat. Therefore, to model the phylogeography of a primary colonizer and the population structure of anurans in northern landscapes, population genetics analyses of wood frogs (Lithobates sylvaticus) were performed in the James Bay area. Wood frogs were sampled from 17 localities around James Bay and genetic analyses were conducted with seven microsatellite loci and mitochondrial DNA sequences of the ND2/tRNATRP genes. Results show that the post-glacial recolonization of the James Bay area by wood frogs originated from the putative refugium in western Wisconsin, an area known as the Driftless Area. Two routes were taken by founders to colonize the James Bay area: one north-west of Lake Superior, colonizing western Ontario, and one through the Upper Peninsula of Michigan, colonizing southern and eastern Ontario and western Québec. Interestingly, the meeting of the two lineages south-west of James Bay led to the establishment of a zone of higher genetic variation than expected under the founder effect hypothesis. Additionally, population structure analyses revealed the segregation of three genetic populations east, north-west, and south-west of the bay, the latter showing the highest genetic variation and likely representing a zone of secondary contact. This study shows that past events such as post-glacial range expansions can explain present patterns of genetic variation and population structure, and that studies in northern landscapes may be very useful in understanding genetic patterns throughout the range of a species.
The role of water clarity in structuring niche dimensions and overlap between smallmouth bass and walleye
(Laurentian University of Sudbury, 2013-07-30) Stasko, Ashley D.
Smallmouth bass (Micropterus dolomieu) have experienced substantial range expansions in northern Ontario over the past century, with adverse consequences for native salmonid predators. It is unclear how climate-induced water clarity shifts will affect interactions between native dark-adapted walleye (Sander virteus) and invading smallmouth bass in northern Ontario. This study used stable isotopes of nitrogen (15N/14N) and carbon (13C/12C) in fish muscle tissue to investigate how resource partitioning between walleye and smallmouth bass is related to water clarity in 34 small (100-200 ha) Boreal Shield lakes (ranging from 1 to 8.5 m Secchi depth, and from 3.2 to 13.1 mg/L DOC). Quantitative metrics of trophic niche dimensions (based on the size, position, and dispersion of multivariate ellipses drawn around sampled individuals in δ15N vs. δ13C biplot space) were calculated for each individual population and used to determine trophic interactions and niche overlap between sympatric walleye and smallmouth bass. Linear and multiple regressions were then used to explore potential relationships between trophic interactions and water clarity. Available habitat and fish assemblage data was also explored for potential influences on isotopic niche dimensions and trophic interactions of walleye and smallmouth bass. Total occupied niche space decreased significantly with increasing water clarity for smallmouth bass as populations occupied a narrower range of trophic levels and made greater use of pelagic resources. In contrast, walleye trophic niche dimensions did not respond significantly to water clarity. Isotopic niche overlap ranged from 0 to 65%, but no metric of trophic overlap was significantly related to water clarity. Other abiotic and biotic variables, however, did have a significant influence on the similarity between some aspects of walleye and smallmouth iv bass isotopic niche dimensions (but not interaction). Both species fed on more isotopically similar carbon sources as lakes became shallower, which may be a result of a lack of distinct littoral and limnetic habitats. Walleye and smallmouth bass niche size also became more similar with increasing DOC but this may be a result of lower prey diversity. Both species also occupied more similar average food web positions as yellow perch relative abundance increased, indicating that the exploitation of yellow perch by both species increased with perch abundance. Together with other studies that have found little evidence for an impact of smallmouth bass on walleye fitness and abundance, this research suggests that, unlike salmonid and cyprinid species, walleye may be resilient against smallmouth bass invasions regardless of water clarity conditions in oligotrophic boreal lakes.
Foot-transmitted vibration: exposure characteristics and the biodynamic response of the foot
(Laurentian University of Sudbury, 2013-07-30) Goggins, Katie A.
Research shows miners can be exposed to foot-transmitted vibration (FTV) when operating various pieces of underground mining equipment, and case reports suggest workers are experiencing symptoms similar to those of hand-arm vibration syndrome in their feet. A field study was conducted to measure and document FTV exposure associated with operating underground mining equipment, and probable health risks were determined based on both ISO 2631-1 (1997) for WBV and ISO 5349-1 (2004) for HAV. Seventeen participating operator’s also reported musculoskeletal discomfort. Seventeen male participants ranging between 24-61 years of age, with an average height and mass of 175.0cm and 88.2kg volunteered for the study. Seventeen pieces of equipment were tested; 1 locomotive, 1 crusher, 9 bolter drills (4 scissor platforms, 2 Maclean, 2 Boart/basket, and 1 RDH), and 6 jumbo drills. Including all seventeen pieces of underground mining equipment, the vibration acceleration ranged from 0.13-1.35m/s2 with dominant frequencies between 1.25-250Hz according to ISO 2631-1. According to ISO 5349-1 vibration acceleration ranged from 0.14-3.61m/s2 with dominant frequencies between 6.3-250Hz. Furthermore, the magnitude of FTV measured on the jumbo drills with grated platforms (#5 and #6) was less than FTV measured from the jumbo drills with, solid metal surfaces. Additionally, twelve of the seventeen equipment operators indicated a complaint of discomfort in their lower body (specifically at the level of the knee or lower). The health risk analysis based on ISO 2631-1 indicated that one operator (bolter drill #9) was exposed to vibration above the criterion value, while the health risk analysis based on ISO 5349-1 indicated iv that two operators (jumbo drill #1 and bolter drill #1) were exposed to vibration above the criterion value. Operators reported very severe or severe discomfort; however, the same operators were not the operators of the equipment with FTV exposure levels above the ISO standards, leaving evidence to suggest that the standards are not properly assessing injury risk to vibration exposure via the feet. Future research is needed to develop a standard specific for FTV and to determine the link between early musculoskeletal injury reporting and the onset of vibration white foot. To do so, a better understanding of the biodynamic response of the foot to FTV is needed. A laboratory study was conducted to 1) measure and document transmissibility of FTV from (a) floor-to-ankle (lateral malleolus), and (b) floor-to-metatarsal, during exposure to six levels of vibration (25Hz, 30Hz, 35Hz, 40Hz, 45Hz, and 50Hz) while standing, and 2) to determine whether independent variables (vibration exposure frequency, mass, arch type) influence transmissibility (dependent variable) through the foot. A two-way repeated measures analysis of variance (ANOVA) was conducted. There was a significant interaction between transmissibility location and exposure frequency (λ = 0.246, F (5,25) = 15.365, p = 0.0001). There were significant differences in mean transmissibility between the ankle and metatarsal at 40Hz [t(29) = 4.116, p = 0.00029], 45Hz [t(29) = 6.599, p = 0.00000031], and 50Hz [t(29) = 8.828, p = 0.000000001]. The greatest transmissibility at the metatarsal occurred at 50Hz and at the ankle (lateral malleolus) transmissibility was highest from 25-30Hz, indicating the formation of a local resonance at each location. v Future research should focus on identifying resonance frequencies at different locations on the feet. This information is needed to develop an exposure guideline to help protect workers from exposure to FTV, and to develop personal protective equipment capable of attenuating harmful FTV exposure frequencies.
Comparative morphogenesis of cynipid leaf galls induced by Diplolepis polita and Diplolepis nebulosa (Hymenoptera: Cynipidae) and modification by inquilines of the genus Periclistus (Hymenoptera: Cynipidae)
(Laurentian University of Sudbury, 2013-07-30) Fenwick, Brandy
Cynipid galls are atypical plant growths induced by wasps in the family Cynipidae that provide larvae with shelter and nutrition. Larvae gain control of attacked plant organs and send them on a new developmental trajectory, with three developmental phases known as initiation, growth, and maturation. Each of the approximately 1400 species of cynipid gall wasps manipulates plant tissues in a slightly different manner such that galls of each species are structurally distinct. Although the means by which cynipids initiate galls has fascinated naturalists for hundreds of years, the basic events in gall induction are still poorly understood. In an attempt to understand the galling strategies and developmental processes responsible for species-specific galls, I chose to compare the intimate details of life history strategies of two taxonomically related species attacking the same plant organs. The strategies included host specificity, phenology, and oviposition strategies, along with gall development to highlight basic events in gall biology and reveal possible stages in past speciation events. It is argued that differences in phenology and gall development played a role in driving speciation and thus, the patterns observed today are a result of extensive ecological interactions in the past that have influenced the evolution of these complex insect-plant relationships. Two species of cynipid wasps of the genus Diplolepis that occur on the wild roses of central Ontario proved to be ideal candidates for the study. One species, Diplolepis polita, induces single-chambered, prickly galls found in clusters on the adaxial surface of leaflets of Rosa acicularis whereas, the other species, D. nebulosa, induces single-chambered, smooth-surfaced galls found in clusters on the abaxial surface of the leaflets of Rosa blanda. Galls at all stages of development, from freshly oviposited eggs to maturation, were found in large numbers for both species. Leaf tissues from the bud stage to maturity of both species of rose were fixed in FAA, embedded in paraffin, sectioned and stained for histological study. Likewise, leaf tissues with freshly oviposited eggs of both species and galls from immaturity to maturity were fixed, sectioned, and stained. Comparing the several thousand slides made for the study revealed that galls of D. polita and D. nebulosa differ in their developmental events as well as the anatomy of their mature galls. Like the galls of all species of cynipids, those of D. polita and D. nebulosa are composed of distinct layers of gall cells known as nutritive, parenchymatous nutritive, sclerenchyma, cortex, and epidermis. Galls of D. polita consist of nutritive cells, parenchymatous nutritive cells, and an epidermis throughout the initiation and growth phases. Larvae remain small in relation to chamber volume until the maturation phase, when a hard layer of sclerenchyma differentiates. In contrast, galls of D. nebulosa have a delayed initiation phase, where galls remain nearly undetectable on leaflets for several weeks after oviposition before they enter the growth phase. Freshly-hatched larvae are protected by two layers of bowl-shaped patches of sclerenchyma that differentiates soon after initiation, along with nutritive cells and parenchymatous nutritive cells that surround the larval chambers, but galls of this species develop without an external layer of epidermis. Galls become spherical as they mature and a second layer of sclerenchyma differentiates within the walls of the galls, as does a layer of spongy cortex that appears between the second layer of sclerenchyma and the gall exterior. Larvae of D. nebulosa occupy nearly the entire volume of their larval chambers throughout gall development. The size of each type of cell found within developing galls of both species, from gall initiation to gall maturity were measured and compared. Cells in the galls of both species continue to increase in size throughout development; however, the cells comprising the galls induced by D. polita are significantly larger than those induced by D. nebulosa. Comparing the biologies and galls of these two species, demonstrates how niche partitioning has occurred. It also shows that striking differences in structures occur within the galls of closely taxonomically related species as a result of differences in adult phenology, oviposition strategies, egg placement, and environmental conditions such as moisture levels. Although it has been proposed by other authors that diversity in cynipid galls results from differentiation of tissues found in the outer parts of galls, such as cortex and epidermis, the present study indicates the reasons are more complex. Furthermore, it is apparent that many aspects of gall development and anatomy have been overlooked by previous researchers and a variety of ecological factors contribute to differences in gall structure. To further complicate the already complex series of events that occur over the course of gall development, galls of D. polita and D. nebulosa are inhabited and structurally modified by inquilines of the genus Periclistus. These insects are also cynipid wasps, and have evolved a close relationship with Diplolepis galls whereby they kill the inducer larvae, feed on gall cells, and change the developmental trajectory of attacked galls. Galls of D. polita and D. nebulosa are attacked by two undescribed, but gall-specific species of Periclistus. Here, the inquiline associated with the galls of D. polita is referred to as Periclistus 1 and the inquiline associated with galls of D. nebulosa is referred to as Periclistus 2. The purpose of this study was to histologically examine all phases of modification by the two species of Periclistus to establish the events that are developmentally unique to inquilines. Periclistus 1 and 2 are phenologically distinct as Periclistus 1 oviposits into immature galls of D. polita in late May soon after galls are induced, and Periclistus 2 oviposits into immature galls of D. nebulosa in July. Modified galls of D. polita differ from modified galls of D. nebulosa as they are significantly enlarged compared to normal galls. Periclistus 1 chambers are arranged around the periphery of the inner gall whereas modified galls of D. nebulosa are of a similar size to normal galls. Chambers of Periclistus 2 are evenly distributed throughout the inner gall. Periclistus 1 and 2-modified galls undergo four phases of development identified as the egg phase, gall enlargement, chamber formation, and maturation phases. Both Periclistus 1 and 2 oviposit into immature galls, killing the inducer larvae with their ovipositors, and then the presence of Periclistus eggs along the inner chamber surface cause changes in gall structure. Diplolepis-induced nutritive cells degrade and Diplolepis-induced parenchymatous nutritive cells enlarge. Galls become significantly enlarged compared to those inhabited by inducer larvae and then feeding by first-instar Periclistus larvae stimulates the differentiation and proliferation of Periclistus-induced parenchymatous nutritive cells and nutritive cells. Immature larvae of both species of Periclistus initially feed around the inner surface of the Diplolepis-induced chamber, and then restrict their feeding to one spot. This results in cell proliferation such that each larva becomes restricted to the centre of a bowl-shaped growth of cells. Continued proliferation causes Periclistus nutritive and parenchymatous nutritive cells to rise up and completely encase the larvae. As this is occurring in modified galls of D. polita, a layer of sclerenchyma, referred to here as the inquiline-induced primary sclerenchyma, differentiates and circumscribes the periphery of the entire gall. This does not occur in galls of D. nebulosa until maturity. In modified galls of both species, nutritive cells and parenchymatous nutritive cells appear in dense clusters throughout the inside surface of Periclistus chambers. Once modified galls enter the maturation phase, inquiline-induced primary sclerenchyma differentiates, circumscribing the periphery of galls of D. nebulosa. In addition, Periclistus 1 and 2-inhabited galls both develop a second layer of inquiline-induced sclerenchyma, known as secondary sclerenchyma, around each inquiline chamber. Secondary sclerenchyma cells in the walls of Periclistus chambers are smaller than primary sclerenchyma cells circumscribing the entire gall. Gall cells induced by Periclistus 1 are larger than those induced by Periclistus 2; however, gall cells induced by both species of Periclistus are larger than those of their host Diplolepis galls. Based on differences in phenology, gall development, and final gall structure, modified galls of D. polita and D. nebulosa are anatomically distinct with each species of Periclistus responsible for gall tissues that are species-specific. In addition, the developmental pattern of Periclistus-modified galls is distinct from that of Diplolepis galls, illustrating the level of control inquilines have over the tissues of their host galls. This thesis demonstrates the complex nature of the interrelationships between cynipid wasps of the genera Diplolepis and Periclistus and their host roses. Diplolepis are true gall inducers that have an intimate relationship with the genus Rosa and there are many attributes of the genus Rosa that have contributed to the success of Diplolepis and allowed for their extensive radiation and divergence in their galls. Similarly, Periclistus inquilines have an intimate relationship with Diplolepis and the rose hosts. Periclistus have evolved the ability to manipulate rose tissues that have previously been under the influence of Diplolepis. Based on two species of inquilines examined in this thesis, Periclistus have also evolved an array of phenologies and modification strategies and like the developmental patterns of the Diplolepis, the developmental trajectories of Periclistus are also species-specific. This project has shown that the histological approach to studying cynipid galls, as well as those occupied by Periclistus inquilines, is highly rewarding and contributes to our overall understanding of these fascinating insects.
Examining the Geriatric Content of Canada’s Newest Undergraduate Medical Program: Are Graduates of the Northern Ontario School of Medicine Acquiring the Basic Competencies to Care for an Increasingly Aging Population?
(Laurentian University of Sudbury, 2013-07-31) Leclair Smider, Karen
Inadequate numbers of physicians skilled at providing specialized care of the elderly, has initiated inquiry as to how medical schools will ensure tomorrow’s physicians are capable of providing the most appropriate care for Canada’s growing population of aging seniors. The Canadian Geriatrics Society has responded to such concerns with the establishment of recommended geriatric learning objectives. This thesis examined the geriatric content of the undergraduate curriculum of Canada’s newest medical school, the Northern Ontario School of Medicine, and compared these findings to the Canadian Geriatrics Society’s recommended ‘Core Competencies in the Care of Older Persons for Canadian Medical Students’. While there was a respectful compliance with the recommendations, findings reveal that five of the twenty recommended competencies were absent in the curriculum objectives. Further, present competencies were found to be unequally distributed across the curriculum in relation to both the year and the teaching setting. The results suggest areas for improvement as recommended competencies are intended as a minimum standard for performance in caring for the elderly.
An integrative approach to distinguishing taxonomically challenging microhymenoptera: Eurytomidae (Hymenoptera: Chalcidoidea) associated with cynipid galls on rose.
(Laurentian University of Sudbury, 2013-07-31) Zhang, Yuanmeng Miles
iii Abstract Cynipid wasps of the genus Diplolepis Geoffrey induce galls exclusively on roses. These galls are susceptible to attack by various hymenopteran parasitoids, the most common of which are members of the family Eurytomidae, with 10 described species having been recorded in association with rose galls in Canada. Because of their small size, sexual dimorphism, morphological plasticity and poorly known biology, species identification of eurytomids is often uncertain. This thesis focused on identifying the eurytomids associated with the galls of the 14 native species of Diplolepis in Canada, testing species limits using a combination of morphological, mitochondrial DNA cytochrome c oxidase I (COI), ecological and geographical data. Six morphospecies were identified using morphological characters, while molecular data identified eight haplogroups. COI sequences identified one species of Tenuipetiolus Bugbee and seven species of Eurytoma Illiger, all associated with galls induced by Diplolepis in Canada. Inconsistencies were observed when compared to morphospecies, including four haplogroups within the genus Eurytoma that were overlooked by morphological studies. The morphospecies Eurytoma acuta Bugbee is a junior synonym of Eurytoma discordans Bugbee; however, the high intraspecific genetic divergences suggest the existence of a species complex. Two geographically sympatric but genetically distinct haplogroups were found within the morphospecies Eurytoma spongiosa Bugbee, “E. spongiosa 2” being a new species that was previously overlooked. An identification key along with (re)descriptions of all identified species was provided. This integrative taxonomy approach confirmed the oligophagous nature of most eurytomids, and provides new insight into the life history strategies of these parasitoids.
Analysis of RBM5 and RBM10 expression throughout H9C2 skeletal and cardiac muscle cell differentiation.
(Laurentian University of Sudbury, 2013-07-31) Loiselle, Julie Jennifer
RNA Binding Motif (RBM) domain proteins RBM5 and RBM10 have been shown to influence apoptosis, cell cycle arrest and splicing in transformed cells. In this study, RBM5 and RBM10 were examined in non-transformed cells in order to gain a wider range of knowledge regarding their function. Expression of Rbm5 and Rbm10, as well as select splice variants, was examined at the mRNA and protein level throughout H9c2 skeletal and cardiac myoblast differentiation. Results suggest that Rbm5 and Rbm10 may (a) be involved in regulating cell cycle arrest and apoptosis during skeletal myoblast differentiation and (b) undergo post-transcriptional or translational regulation throughout myoblast differentiation. All in all, the expression profiles obtained in the course of this study will help to suggest a role for Rbm5 and Rbm10 in differentiation, as well as possible differentiation-specific target genes with which they may interact.
Imaging, characterization and processing with axicon derivatives.
(Laurentian University of Sudbury, 2013-08-06) Saikaley, Andrew Grey
Axicons have been proposed for imaging applications since they offer the advantage of extended depth of field (DOF). This enhanced DOF comes at the cost of degraded image quality. Image processing has been proposed to improve the image quality. Initial efforts were focused on the use of an axicon in a borescope thereby extending depth of focus and eliminating the need for a focusing mechanism. Though promising, it is clear that image processing would lead to improved image quality. This would also eliminate the need, in certain applications, for a fiber optic imaging bundle as many modern day video borescopes use an imaging sensor coupled directly to the front end optics. In the present work, three types of refractive axicons are examined: a linear axicon, a logarithmic axicon and a Fresnel axicon. The linear axicon offers the advantage of simplicity and a significant amount of scientific literature including the application of image restoration techniques. The Fresnel axicon has the advantage of compactness and potential low cost of production. As no physical prior examples of the Fresnel axicons were available for experimentation until recently, very little literature exists. The logarithmic axicon has the advantage of nearly constant longitudinal intensity distribution and an aspheric design producing superior pre-processed images over the aforementioned elements. Point Spread Functions (PSFs) for each of these axicons have been measured. These PSFs form the basis for the design of digital image restoration filters. The performance of these three optical elements and a number of restoration techniques are demonstrated and compared.
XRD structural assessment of peridotitic garnet with anomalous REE distribution
(2013-08-15) Campbell Ross, Kirk
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.
The implementation of a structured format of brief cognitive behaviour therapy (CBT) methods to overcome the barriers and facilitate the delivery of CBT by primary healthcare providers for patients with depression: a pilot evaluation
(2013-09-11) Barban, Karen
Cognitive behaviour therapy is a well-documented first-line treatment for mild to moderate depression. Primary healthcare providers have encountered several barriers when trying to provide CBT in an office-based setting and as such, adoption of this evidence-based treatment has been suboptimal. Primary healthcare nurse practitioners (PHC NPs) have an in-depth knowledge of advanced nursing practice, and are responsible for the assessment, diagnosis and management of patients with acute and chronic conditions, such as depression. PHC NPs are also ideally situated in the health care system to deliver CBT to their patients. The objectives of this project were to develop a format for the delivery of brief CBT methods that was feasible in the PHC setting, increase PHC providers’ confidence to implement CBT and ultimately increase their adoption of CBT
Absenteeism in a health care setting
(Laurentian University of Sudbury, 2013-09-12) Sherrington, Steven
Not provided
L'éducation physique et santé après la 9e annnée du secondaire en Ontario : le problème de la participation effective des élèves.
(Laurentian University of Sudbury, 2013-10-02) Dagostino, Chantal
Ce mémoire fait un survol du problème de la non-participation effective des élèves aux cours d’Éducation Physique et Santé (ÉP.S) après la neuvième année du niveau secondaire en Ontario. Il est composé de cinq chapitres. Le premier chapitre de ce mémoire présente la nature de l’ÉP.S, son importance dans chaque province et territoire du Canada, et le programme-cadre de l’ÉP.S. en Ontario. Il termine par l’énonciation de la préoccupation des enseignantes et des enseignants d’ÉP.S au regard de la non-participation des élèves aux cours d’ÉP.S après la classe de 9e année du secondaire. Le deuxième chapitre, quant à lui, synthétise le cadre théorique explicatif du phénomène de la non-participation des élèves aux cours d’ÉP.S après la classe de 9e année du secondaire. Il présente la théorie de la motivation. Le chapitre trois expose les principaux facteurs inhibiteurs et motivationnels à la participation des élèves aux cours d’éducation physique et santé, et ce, tels que ces facteurs se présentent dans la recherche. Le chapitre quatre est relatif aux suggestions à l’endroit du personnel politique des curriculums et des enseignants en vue d’espérer voir s’augmenter la participation des élèves aux cours d’éducation physique et santé. Enfin, le chapitre cinq qui conclue le travail reprend les grandes lignes de la recherche et énonce des pistes de recherche pour le futur.
Unveiling the metabolic network underlying mitochondrial and nuclear metabolism in a model differentiating stem cell
(Laurentian University of Sudbury, 2013-10-07) Han, Sungwon
Participation of metabolism in stem cell differentiation has been largely disregarded until recently. Here, functional proteomics and metabolomics were performed to unveil the mitochondrial and nuclear metabolism during dimethyl sulfoxide (DMSO)-induced differentiation of P19 cells. DMSO-treated cells were shown to exhibit increased glycolytic enzymes activities and fuel pyruvate into oxidative phosphorylation. Subsequently, enzymes of electron transport chain also had elevated activities upon differentiation. These changes in mitochondrial metabolism were concomitant with increased mitochondrial biogenesis as PGC-1α expression was higher in the differentiated cells. To study nuclear metabolism, particular focus was placed on delineating a potential role of nuclear lactate dehydrogenase (LDH). Nuclear LDH was found to exhibit higher expression in pluripotent cells. NAD+ generated from LDH reaction was discovered to promote histone deacetylation via sirtuin-1 (SIRT1). Drastic alterations in mitochondrial and nuclear metabolism during differentiation point to a pivotal role of metabolism in deciding the final destination of stem cells.
Evaluation of liposomal bismuth-ethanedithiol-tobramycin for treatment of cystic fibrosis pulmonary pseudomonas aeruginosa infection
(Laurentian University of Sudbury, 2013-10-08) Alhariri, Moayad Abdulaziz I.
The effectiveness of liposomes incorporating bismuth-ethanedithiol and loaded with tobramycin (LipoBiEDT-TOB) at sub-inhibitory concentrations to inhibit the production of quorum sensing signaling molecules and virulence factors induced by P. aeruginosa was evaluated in vitro. In addition, we evaluated the efficacy and safety of free and encapsulated tobramycin in liposomal formulations administered intratracheally to rats chronically infected with P. aeruginosa. LipoBiEDT-TOB significantly reduced the production of quorum sensing signaling molecules and virulence factor secretion compared to free tobramycin. The LipoBiEDT-TOB formulation significantly reduced the bacterial count in lungs, modulated the IL-8 level in blood and minimized the nephrotoxicity that is associated with aminoglycoside treatment. These results support the hypothesis that aerosolization of liposomal aminoglycosides may enhance the management of chronic lung infections caused by resistant P. aeruginosa in patients with cystic fibrosis.
Attitudes of registered nurses, allied health professionals, and clerical staff towards multi-disciplinary teamwork
(Laurentian University of Sudbury, 2013-10-08) Guido, Pina Rita
Although teamwork is essential for quality care, outcomes based on successful teamwork are seldom achieved in healthcare. Negative attitudes prevent effective teamwork; therefore, it is important to explore attitudes of all members towards multi-disciplinary teamwork. This research investigated attitudes held by health professionals and staff of the Group Health Centre regarding multi-disciplinary teamwork and investigated if a relationship exists between work experience and attitudes towards teamwork. A descriptive correlational design was used. Data was gathered using the TeamSTEPPS Teamwork Attitude Questionnaire (T-TAQ). The T-TAQ assesses attitudes towards validated constructs of teamwork. Team members of the Group Health Centre have positive attitudes towards teamwork. The registered nurses do not have different attitudes compared to their colleagues from other health sciences or staff. However, clerical staff presents differences with respect to the constructs of situation monitoring and communication. There is no relationship between work experience and attitudes. These results have important implications for teams in primary care, specifically, the Group Health Centre.
Are all stereotypes created equal? Examining gender as a moderator of event-related potentials evoked during schema violation
(Laurentian University of Sudbury, 2013-10-08) Schubert, Christopher
Schema violation has been shown to have an impact on cognition. Previous research using reading tasks has shown that the impact is not the same across male and female characters, and research has shown that men and women hold different view of schemas. The Implicit Association Test (IAT) has been used as a method to investigate schema violation, but no study has effectively investigated gender differences. Therefore, this study specifically investigates the factors of participant and character gender on schema violation during the IAT. Event-related potentials (ERPs) were used to investigate the cognitive impact of schema violation while participants completed gender and sexuality IATs. Significant effects were found for participant gender and character gender in several ERP components (N100, P200, N400, and LPP), but only for the gender-career IAT. This suggests that on a basic cognitive level ERP activity is influenced by gender.
Design, construction and validation of internal organ phantoms for biomechanical testing
(Laurentian University of Sudbury, 2013-10-08) Omri, Karim
This thesis includes the development, construction and testing of internal organ phantoms, with focus on the liver, for biomechanical testing. Phantoms have various biomedical applications such as surgical simulations, minimally invasive surgery, soft tissue characterization, diagnostic tools and instrumentation calibration. However, there is little work present in literature regarding phantoms and the work that is currently available does not account for the non-linear viscoelastic properties as well as the Glisson’s capsule. In this work, three different phantoms are presented: a fluid-filled phantom, a perfused phantom and a hydrogel-based liver phantom. A testing apparatus is designed, built and used to measure the force-displacement data during the indentation of the phantom. The first phantom that is designed and constructed follows the basis of a fluid-filled vessel. It is composed of a linear low-density polyethylene (LLDPE) bag filled with different fluids namely: water, a 1:1 water/glycerine mixture and glycerine. The phantoms are subjected to quasi-static loading as well as relaxation testing. The effect of density and viscosity, its size, and confined and unconfined boundary conditions are characterized. The second phantom is designed to investigate the effects of hepatic macrocirculation on the biomechanical properties of the liver. The phantom is made of two-part silicone (Smooth-On, ECOFLEX 00-30), and contains a network of conduits to model the large ! iv! blood vessels in the liver. A perfusion system that captures the general features of the human hepatic circulation is used to help investigate the effects of the different flow parameters such as pressure and flow rate on the biomechanical characteristics of the liver. The perfusion system is designed to reproduce comparable pressures to the human portal vein and hepatic artery. The third phantom is made of two parts, a hydrogel inner layer with a LLDPE outer layer. The idea behind this phantom is to represent the organ as accurately as possible by accounting for the capsule that surrounds the organ as well as the biphasic (solid and fluid) nature of the organ. A biphasic poroviscoelastic model is used to model the hydrogel while the LLDPE uses a non-linear hyperelastic and viscoelastic model. Modeling is done in ABAQUS to fit the experimental data obtained from quasi-static indentation and relaxation testing using a parametric study. In conclusion, phantoms replicating the non-linear viscoelastic properties observed in organs are presented and characterized. Main Thesis Contributions • Development and characterization of a simple fluid-filled phantom to represent the mechanical properties of the liver • Development and characterization of hydrogel-based liver phantom with representation of the biphasic nature of the organ and the Glisson’s capsule. ! v! • Development and characterization of perfused liver phantom with ability to be recreated with various vessel configurations. • Development of testing set-up to characterize various phantoms.
Generating random shapes for Monte Carlo accuracy testing of pairwise comparisons
(Laurentian University of Sudbury, 2013-10-08) Almowanes, Abdullah
This thesis shows highly encouraging results as the gain of accuracy reached 18.4% when the pairwise comparisons method was used instead of the direct method for comparing random shapes. The thesis describes a heuristic for generating random but nice shapes, called placated shapes. Random, but visually nice shapes, are often needed for cognitive experiments and processes. These shapes are produced by applying the Gaussian blur to randomly generated polygons. Afterwards, the threshold is set to transform pixels to black and white from di erent shades of gray. This transformation produces placated shapes for easier estimation of areas. Randomly generated placated shapes are used to perform the Monte Carlo method to test the accuracy of cognitive processes by using pairwise comparisons. An on-line questionnaire has been implemented and participants were asked to estimate the areas of ve shapes using a provided unit of measure. They were also asked to compare the shapes in pairs. Such Monte Carlo experiment has never been conducted for 2D case. The received results are of considerable importance.
True lies : who can learn to tell?
(Laurentian University of Sudbury, 2013-10-08) Pote, Emma C.
Non-verbal cues can provide behavioural signals of deception to observers. Microexpressions are facial cues that indicate the presence of an emotion being concealed by a deceiver. During deception, deceivers often attempt to conceal an emotion by masking it with an expression of another emotion such as a smile. Despite this, micro-expressions may be leaked during masking to reveal the hidden emotion. Nonetheless, research has shown that the majority of people recognize the occurrence of deception no better than could be expected by chance. Micro-expression detection training has been suggested to improve micro-expression detection skill that is linked to improved deception detection. The present study examined the effectiveness of the Micro-expression Training Tool (METT) in improving students’ and police officers’ skills in detecting masking smiles. The visual attention of trainees and untrained controls was measured via eye tracking during a pre and post test masking smile detection task. Results revealed that training did not have an effect on task performance, but practice did alter task performance. Following practice, all groups showed better detection of true smiles but not for masking smile detection. Participants’ abilities to identify masked emotions and location of microexpressions on the face varied as a function of the emotion present, as did their attention to the relevant regions of the face that contained a micro-expression. These results suggest that traditional micro-expression training is not sufficient to train observers in masking smile detection. This result has significant implications for future training protocols and many professional groups, as masking smiles are often employed during attempts at deception.

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