Caractérisation de la surface d'implants de titane et de cobalt-chrome par la dimension fractale et l'influence de la topographie sur les interactions interfaciales

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal

Spatio-Temporal Analyses of Cenozoic Normal Faulting, Graben Basin Sedimentation, and Volcanism around the Snake River Plain, SE Idaho and SW Montana

This dissertation analyzes the spatial distribution and kinematics of the Late Cenozoic Basin and Range (BR) and cross normal fault (CF) systems and their related graben basins around the Snake River Plain (SRP), and investigates the spatio-temporal patterns of lavas that were erupted by the migrating Yellowstone hotspot along the SRP, applying a diverse set of GIS-based spatial statistical techniques. The spatial distribution patterns of the normal fault systems, revealed by the Ripley\u27s K-function, display clustered patterns that correlate with a high linear density, maximum azimuthal variation, and high box-counting fractal dimensions of the fault traces. The extension direction for normal faulting is determined along the major axis of the fractal dimension anisotropy ellipse measured by the modified Cantor dust method and the minor axis of the autocorrelation anisotropy ellipse measured by Ordinary Kriging, and across the linear directional mean (LDM) of the fault traces. Trajectories of the LDMs for the cross faults around each caldera define asymmetric sub-parabolic patterns similar to the reported parabolic distribution of the epicenters, and indicate sub-elliptical extension about each caldera that may mark the shape of hotspot’s thermal doming that formed each generation of cross faults. The decrease in the spatial density of the CFs as a function of distance from the axis of the track of the hotspot (SRP) also suggests the role of the hotspot for the formation of the cross faults. The parallelism of the trend of the exposures of the graben filling Sixmile Creek Formation with the LDM of their bounding cross faults indicates that the grabens were filled during or after the CF event. The global and local Moran’s I analyses of Neogene lava in each caldera along the SRP reveal a higher spatial autocorrelation and clustering of rhyolitic lava than the coeval basaltic lava in the same caldera. The alignment of the major axis of the standard deviational ellipses of lavas with the trend of the eastern SRP, and the successive spatial overlap of older lavas by progressively younger mafic lava, indicate the migration of the centers of eruption as the hotspot moved to the northeast

Spatio-Temporal Analyses of Cenozoic Normal Faulting, Graben Basin Sedimentation, and Volcanism around the Snake River Plain, SE Idaho and SW Montana

This dissertation analyzes the spatial distribution and kinematics of the Late Cenozoic Basin and Range (BR) and cross normal fault (CF) systems and their related graben basins around the Snake River Plain (SRP), and investigates the spatio-temporal patterns of lavas that were erupted by the migrating Yellowstone hotspot along the SRP, applying a diverse set of GIS-based spatial statistical techniques. The spatial distribution patterns of the normal fault systems, revealed by the Ripley\u27s K-function, display clustered patterns that correlate with a high linear density, maximum azimuthal variation, and high box-counting fractal dimensions of the fault traces. The extension direction for normal faulting is determined along the major axis of the fractal dimension anisotropy ellipse measured by the modified Cantor dust method and the minor axis of the autocorrelation anisotropy ellipse measured by Ordinary Kriging, and across the linear directional mean (LDM) of the fault traces. Trajectories of the LDMs for the cross faults around each caldera define asymmetric sub-parabolic patterns similar to the reported parabolic distribution of the epicenters, and indicate sub-elliptical extension about each caldera that may mark the shape of hotspot’s thermal doming that formed each generation of cross faults. The decrease in the spatial density of the CFs as a function of distance from the axis of the track of the hotspot (SRP) also suggests the role of the hotspot for the formation of the cross faults. The parallelism of the trend of the exposures of the graben filling Sixmile Creek Formation with the LDM of their bounding cross faults indicates that the grabens were filled during or after the CF event. The global and local Moran’s I analyses of Neogene lava in each caldera along the SRP reveal a higher spatial autocorrelation and clustering of rhyolitic lava than the coeval basaltic lava in the same caldera. The alignment of the major axis of the standard deviational ellipses of lavas with the trend of the eastern SRP, and the successive spatial overlap of older lavas by progressively younger mafic lava, indicate the migration of the centers of eruption as the hotspot moved to the northeast

Écoulements granulaires par avalanches : indices de fluidité, fractales et multifractales

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal

Biomechanics of the Hominin Upper Limb: Entheseal Development and Stone Tool Manufacture

The close association of the advent of tool behaviours with changes to the upper limb morphology of fossil hominins has lead researchers to hypothesise that stone tool manufacture and use represents an important selective pressure for the upper limb, and yet the makers of the first stone tools, the Oldowan technological complex, remain obscure. Entheseal complexity studies have suggested that morphological changes to muscle attachment sites might be a fruitful means to investigate activity patterns in past populations. The aims of this study were therefore two-fold. First, upper limb kinetics, kinematics, and normal activation patterns of 15 shoulder and elbow muscles were investigated using electromyography (EMG) in 16 novices during Oldowan stone knapping to identify which muscles were highly and regularly recruited during this behaviour. Second, upper limb entheses in 10 species of fossil hominin were analysed using fractal analysis to score entheseal complexity. These results were then compared with the EMG analysis to determine whether patterns of entheseal complexity mirror muscle recruitment patterns in living subjects. If so, it may be possible to identify who made the first stone tools. The results of the biomechanical study indicate that the motion of the knapping arm in stone tool manufacture is a dynamic three-dimensional flexion-extension motion. The shoulder and elbow musculature is active primarily to produce acceleration of the arm segments to generate the strike force. The segments of the upper limb moved in a coordinated proximal-to-distal sequence. This motion originated with the shoulder proximally in the up-swing or “cocking” phase and was transmitted through to the distal limb segments (the wrist and hammerstone) in the down-swing phase. The principle strike force-generating muscles of the down-swing are Mm. latissimus dorsi, teres major, and triceps brachii. M. pectoralis major works during this phase to decelerate the rapidly extending arm to improve strike accuracy. The wrist flexor and extensor musculature, rather than producing specific motion of the wrist, appears to be highly recruited to stabilise the elbow and wrist against reactive forces from hammerstone impact. The entheseal complexity analysis indicates that potential members of the tool-making guild include Australopithecus africanus, Australopithecus anamensis, Paranthropus robustus, Homo habilis, and Homo ergaster. While patterns of entheseal complexity in the fossil hominin upper limb do indeed mirror muscle recruitment patterns during stone knapping, the data is nonetheless equivocal as morphological evidence in at least two candidate species (one of which occurs 1.5 Ma prior to the first evidence of the Oldowan technological complex) suggests strong commitment to arboreality, calling into question the efficacy of entheseal complexity studies for identifying activity patterns in fossil hominins

MS FT-2-2 7 Orthogonal polynomials and quadrature: Theory, computation, and applications

Quadrature rules find many applications in science and engineering. Their analysis is a classical area of applied mathematics and continues to attract considerable attention. This seminar brings together speakers with expertise in a large variety of quadrature rules. It is the aim of the seminar to provide an overview of recent developments in the analysis of quadrature rules. The computation of error estimates and novel applications also are described