A comprehensive understanding of sex-specific gait patterns throughout the lifespan is important considering differences between males and females that can manifest biomechanically, and epidemiological evidence of female sex being a risk factor for some age-related pathologies such as osteoarthritis. This thesis aimed to, 1) characterize the differences in lower extremity joint kinematics and kinetics during gait between healthy women and men in different age groups, and 2) define salient inter-joint kinematic coordination strategies in healthy adult gait. Gait data from 154 asymptomatic adult participants was analyzed. Waveform principal component analysis (PCA) was applied to hip, knee and ankle joint angles and net external moments to extract major patterns of variability. Using a two-factor ANOVA, PC scores were examined for significant sex, age and interaction effects. A second series of PCA models were also developed with the PC scores of the kinematic features of each joint to model the inter-joint kinematic coordination. Demographics, anthropometrics and root mean square (RMS) of EMG waveforms for the high and low groups (85th and 15th percentile) of the retained kinematic strategies were statistically compared using a one-way ANOVA analysis. 13 PC features differed between healthy male and female gait patterns and were independent of age category. No PC features significantly differed between the age groups, and there was no significant sex by age interactions. Four different kinematic gait coordination strategies were identified, one with a significant sex-effect. Therefore, both analyses supported sex-differences in gait biomechanics and the importance of using sex-specific normative data in clinical gait studies. Additionally, the results suggest underlying kinematic differences within asymptomatic adults are concentrated in the patterns of their gait mechanics. Understanding how these strategies may link to susceptibility of injury and disease has important implications for patient-centered care and may provide important insight into age-related pathology and disease. / Thesis / Master of Applied Science (MASc) / Since variability in healthy walking gait strategies may provide evidence for early mobility decline, this thesis aimed to identify the primary walking gait strategies in a healthy adult population. This work is distinct from previous work in that it comprehensively investigates the influence of sex and age on walking gait features and simultaneously defines primary walking gait strategies in healthy adults. The results indicate an overall difference in walking strategy between healthy male and female adults but no significant differences with age, indicating that age-matching for gait studies using adult controls is not as critical as sex considerations. Additionally, the results suggest that gait differences within healthy adults are concentrated in the patterns of their gait mechanics. Understanding how these strategies may link to susceptibility of injury and disease may provide important insight into age-related mobility limitations and help improve mobility longevity in the aging population.

We studied root kinematics in relation to temperature and genome size variation in teosinte (Zea mays subspecies parviglumis) and corn (Zea mays subspecies mays). Corn had significantly faster radicle growth than teosinte when grown at a constant temperature. Both species exhibited variation in seed size and for each species larger seeds had faster root growth. Genome size was not significantly correlated with faster radicle growth rates across multiple land races of corn. To examine temperature dependent growth in corn and teosinte, a germinated seedling was grown at multiple temperatures. Growth rates at these temperatures were used to fit a temperature response model for each species. Parameters of this model (maximum growth temperature and optimum growth temperature) were not significantly different between the species.

No description available.

No description available.

No description available.

Subduction of an oceanic plate under the Pacific margin of South America has heen prevalent since Jurassic times. Magmatic and deformation centres have migrated eastward since suhduction began. Northern Chile houses two north-south trench linked strike-slip fault systems, the Atacama Fault Zone and the Domeyko Fault System (DFS). The DFS lies within the Chilean Precordillera from 2 10 to 28°S. Lateral movement began on the DFS in the Eocene. The DFS can be divided into three segments which have apparently undergone differing deformation histories. This study has focused on the central segment of the DFS, to determine fault kinematics and to establish a relative chronology of deformation. Observations have been made in more detail than previous investigations and have heen used to infer the deformation history . Shallow level faulting has resulted in heavily fractured zones with occasional slickenline surfaces. It is difficult to infer kinematics of faulting from these. Much effort has been expended in developing techniques to analyse fracture patterns associated with brittle faulting under conditions of plane strain, simple shear. A novel approach of analysing the shapes of clasts of rock defined by secondary fractures within a fault zone has been used. The clasts approximate ellipses when viewed in 2 dimensions. Combining ellipse orientation and aspect ratio from mutually perpendicular sections through the fault zone allowed calculation of an ellipsoid representative of the clasts of rock in 3 dimensions. Independent determination of the fault kinematics using stratigraphic relationships across the fault, fracture distribution, incremental strain axes and palaeomagnetic analysis has all owed evaluation of the new technique. The shapes of rock clasts are found to be related to the kinematics of the fault system. Up to a critical stage of development of the fault zone the axes of the rock clasts parallel the slip direction, intermediate strain axis and pole to the boundary faults. Which rock clast axis parallels which structural feature depends upon the spacing and curvature of fractures and stage of development of the fault zone. Analysis of the shapcs or rock clasts defined by fractures can avoid bias of the data set towards thicker fractures or against irregular fractures, which can occur when measuring fracture orientations directly. The degree of development of the fault zone varies laterally along the fault over short distances. This causes the shape.: fabric of the rock clasts to change, so predictions of connectivity within a fault zone are limited. The history of the central segment of the DFS determined from this study is found to occur with earlier workers. The complementary deformation histories produced from two scales of ohservation verifies the reliability of the chronology. Lateral movements along the DFS are thought to begin in the Eocene with a sinistral transpressive event which occurred along all three segments of the DFS. En echelon folds, east and west verging thrusts and clockwise rotations associated with sinistral faulting along the master fault of the segment are documented. Later, in the Oligocene, dextral faulting occurred. large clockwise palaeomagnetic rotations, determined from Palaeozoic samples beside the master fault, indicate sinistral displacements have been larger than dextral disp acements. It is inferred that only one episode of large lateral transport occurred. This is the Eocene sinistral event. Normal faulting associated with sinistral displ acements along the western side of the system are documented. This later sinistral faulting has not been documented before in the central segment of the DFS. After Oligocene age dextral faulting, the three segments of the DFS underwent separate deformation histories, as the main Andean deformation foci had moved eastward.

INTRODUCTION: Tightness of the hip flexor muscle group may contribute to altered sagittal plane kinematics of the lumbo-pelvic-hip (LPH) complex during dynamic movements. Therefore, the purpose of this study is to analyze the effects of a three-week home-based stretching program on passive hip extension (PHE), as well as on active hip extension (AHE), anterior pelvic tilt (APT), and lumbar spine extension (LSE) when running. METHODS: Twenty healthy subjects with limited PHE underwent a 3D gait analysis both prior (PRE) and following (POST) a three-week static hip flexor stretching program. RESULTS: Following the stretching program, peak PHE increased significantly (P < 0.001), while no significant improvements were reported in AHE, APT, or LSE. In addition, no relationship was found between the change in PHE with either the change in AHE, APT, or LSE. Finally, a high relationship was observed between AHE and APT during running (r = 0.83, p < 0.001), and low relationships were observed between APT and LSE (r = -0.41, p = 0.08) and AHE and LSE (r = -0.34, p = 0.15). CONCLUSION: A three-week static stretching program of the hip flexor musculature resulted in an increase in PHE, but the sagittal plane kinematics of the LPH complex during running remained unchanged. The correlations observed between AHE, APT, and LSE suggest there is a kinematic relationship between the hip, pelvis, and spine.

Understanding the formation and evolution of galaxies is one of the most active areas of research in astrophysics. Hierarchical merging of proto-galactic fragments to build more massive galaxies is the current preferred model. A key prediction of this theory is that haloes of nearby galaxies should contain remnants of this assembly process in the form of tidal debris. Found in all but the smallest of dwarf galaxies, globular clusters (GC) are excellent probes of galaxy haloes. Having high luminosities, they are favourable targets in the outer regions of galaxies where the associated stellar surface brightness is low. GCs are thought to be amongst the oldest stellar systems in the Universe, and are likely born in the most significant phases of galaxy formation. Their metallicities, ages, spatial distributions and kinematics can be used to constrain the assembly history of their host galaxy. In this thesis, I explore the photometric and kinematic properties of several GC systems in our cosmological backyard, the Local Group of galaxies. The work is based on a major spectroscopic campaign, follow-up to the photometric Pan- Andromeda Archaeological Survey (PAndAS), as well as additional optical and near-IR data sets. Radial velocities are obtained for 78 GCs in the halo ofM31, 63 of which had no previous spectroscopic information. The GCs have projected radii between ∼ 20 and 140 kpc, thus sampling the true outer halo of this galaxy. In addition, GCs in the dwarf galaxies NGC 147, NGC 185 and NGC 6822 are also spectroscopically observed. By conducting a detailed kinematic analysis, I find that GCs in the outer halo of M31 exhibit coherent rotation around the minor optical axis, in the same direction as their more centrally located counterparts, but with a smaller amplitude of 86 ± 17 km s−1. There is also evidence that the velocity dispersion of the outer halo GC system decreases as a function of projected radius from theM31 centre, and this relation can be well described by a power lawof index ≈ −0.5. I detect and discuss various velocity correlations amongst GCs that lie on stellar streams in the M31 halo. Simple Monte Carlo tests show that such configurations are unlikely to form by chance, implying that significant fraction of the GCs in the M31 halo have been accreted alongside their parent dwarf galaxies. I also estimate the dynamical mass of M31 within 200 kpc to be (1.2 − 1.6) ± 0.2 × 1012 M⊙. I also characterize the GC systems of three dwarf galaxies in the Local Group: the dwarf elliptical satellites of M31, NGC 147 and NGC 185, and the isolated dwarf irregular NGC 6822. Using uniform optical and near-IR photometry, I constrain the ages and metallicities of their constituent GCs. The metallicities of the GCs around NGC 147 and NGC 185 are found to be metal-poor ([Fe/H]. −1.25 dex), while their ages are more difficult to constrain. The GCs hosted by NGC 6822 are found to be old (>9 Gyr) and to have a spread of metallicities (−1.6 . [Fe/H] . −0.4). I find close similarity between the mean optical (V − I)0 colours of the GCs hosted by these three dwarf galaxies to those located in the M31 outer halo, consistent with the idea that dwarf galaxies akin to them might have contributed toward the assembly of the M31 outer halo GC population. Analysing their kinematics, I find no evidence for systemic rotation in either of these three GC systems. Finally, I use the available GC kinematic data to calculate the dynamical masses of NGC 147, NGC 185 and NGC 6822.

The biomechanics of the overhead throw has been extensively studied in regards to baseball pitching. However, an understanding of the proper mechanics needed to successfully throw a football has not previously been investigated. Thus, the purpose of this study was to investigate the kinematics, kinetics, and electromyography of the football throws in elite quarterbacks. Three collegiate quarterbacks were evaluated using a multi-camera motion capture system and electromyography electrodes. The results of this study are able to give a breakdown in the types of mechanics needed in each of the phases of the throw. This study demonstrated that during the early cocking phase, most of the movement seen in the upper body occurs in the frontal plane to abduct the shoulder. During the late cocking phase, the shoulder holds a constant abduction angle and begins to externally rotate. The shoulder reaches a value of 117° of external rotation, much less than has previously been reported. During the acceleration phase, the shoulder rapidly internally rotates as well as horizontally adducts. Once the ball is released, the shoulder has to produce large forces and muscle activity to slow down the rotation. These results will be able to give coaches and players a tool for what to look for when evaluating the mechanics of an individual.

Triathlon involves three different modes of endurance events, swim, bike and run, consecutively. Transitions between events are critical to be successful in the sport; however, many triathletes report impaired running performance due to adverse residual effects from cycling. One of the strategies that triathletes use to manage the adverse effects is to use a bicycle with a more vertical seat post angle. There is limited evidence that support the effectiveness of such bicycle geometry, but many of these studies lacks ecological validity. Twelve triathletes and cyclists completed a 20-km simulated course with instrumentations for 3D motion, kinetic, and electromyographic analyses under two different seat post angle settings: shallow (ROAD) and steep (TRI). Series of paired-t tests were used for statistical analysis. Results indicated cycling mechanics between two seat post angle conditions were similar; however, the steep condition resulted in time-delay in muscle activation and pedal force application. There was no significant difference in cycling performance. The athletes were able to retain relatively consistent pedaling techniques with modification of seat post angle.