This study was carried out primarily to evaluate the cryo-tolerance of equine semen from four stallions through assessing the spermatozoa motion characteristics with Computer-Assisted Sperm Analysis (CASA). Four stallions were collected during the breeding season (summer). For each ejaculate, fresh and cryopreserved samples were taken for sperm motility characteristics evaluation. Data analysis demonstrated that sperm cells of stallions were significantly affected by (P<0.05) cryodamage. Stallion (A) was cryotolerant, and was classified as a good freezer, whereas stallion (D) was not and classified as a poor freezer regardless of the concentration of sperm. In addition, a concentration of 0.4 x 109 sperm cells/ml had higher percentages of rapid sperm and velocity parameters (P<0.05) compared to 0.8 x 109 sperm/ml. Further research is necessary to identify potential biomarkers for good and poor freezer stallions.

No description available.

<p> An expression for the semiclassical density of states for a particle in a smooth potential well is obtained from the Kirkwood expansion of the partition function. This expression for the semiclassical density of states is then shown to be essentially equivalent to the expression obtained from the Green's function method of Balian and Bloch.</p> <p> The Strutinsky shell correction to the nuclear binding energy is then analytically shown to be equivalent to the shell correction obtained from a consideration of the semiclassical partition function if certain restrictions on the Strutinsky smoothing parameter can be met.</p> / Thesis / Master of Science (MSc)

No description available.

<p> We study a many particle system contained within a harmonic oscillator potential, with the single particle spacings equispaced and nondegenerate. We consider either fermions or bosons within this harmonic oscillator potential and derive the density of states for this system, with low excitation energy corrections. We extend our method for more than one species of fermions or bosons within this harmonic oscillator potential and compare our results with number-theoretic techniques. We move on to the degenerate harmonic oscillator potential and show that, for a fermion system, shell effects are contained within low excitation energy terms. We attempt to arrive at the density of states for an infinite number of bosons within the same potential. </p> / Thesis / Master of Science (MSc)

Exercise associated muscle induced bone strain has potential osteogenic effects that may increase skeletal density, bone cross-sectional area and structural strength. Whether the effects of exercise and the muscle-bone relation are similar in weight bearing and nonweight bearing bones remains to be determined. This study compared bone density, geometry and biomechanical properties, and bone and muscle cross-sectional areas of 13 elite adolescent male cross-country skiers with height, weight, age and maturity matched non-athletic controls. Total bone mineral density (BMDror), and trabecular bone mineral density and total bone cross-sectional area (CSAror) were measured at the distal 4% of the radius (DR) of the dominant (D) and non-dominant (ND) arms, and tibia (DT) using peripheral quantitative computed tomography (pQCT); BMDror, CSAror, cortical BMD, cortical thickness (CrtTH) and area (CSAcoRr), stress-strain index polar, x, y, polar moment of inertia, axial moment of inertia, and muscle cross-sectional area (mCSA) were measured at the 66% length of the proximal tibia (PT) and proximal radius (PR) of the D and ND arms. Whole body BMD, whole body bone area, and hip areal bone mineral density were measured using dual energy X-ray absorptiometry (DXA). Speed of sound along the bone was measured using quantitative ultrasound (QUS) at the 1/3 DR and PT. There were no differences between the skiers and controls for any of the descriptive measures, however, there was a trend (p=0.06) for skiers to have lower percent body fat than controls. There were no differences between skiers and controls for the bone outcome measures using pQCT, DXA or QUS, except for CrtTH at the PT which was significantly higher in skiers (5.42±0.25mm, p=0.03) than controls (5.18±0.28mm). Cross-country skiers had increased CrtTH at the PT suggesting little differential effect of mechanical loading on bone density, geometry or biomechanical properties associated with skiing. / Thesis / Master of Science in Kinesiology

The effect of intense gymnastic training on bone mineral density was investigated in 16 elite prepubertal (9.82 ± 0.89 years) (mean ± SD) gymnasts (GYM) and 16 normoactive (9.87 ± 0.75 years) controls (CON). Pubertal status was determined according to the criteria of Tanner. Additionally the mother of each subject was recruited, and was included in all measurements as an estimate of hereditability. GYM were in elite pre-competitive or competitive programs for at least two years, and trained on average 18 hr per week. Areal bone mineral density (BMD) and body composition (%BF) was measured for the whole body, and BMD for the left hip and lumbar spine (L1-L4) by dual energy x-ray absorptiometry (DXA), and volumetric BMD for the distal radius by peripheral QCT (pQCT). There were no significant differences between groups for age, pubertal status or body mass; however GYM were significantly shorter (129.3 ± 5.7 vs. 136.7 ± 4.4 cm; P<0.01) and leaner (15.12 + 1.95 vs. 19.58 + 4.29 %BF) than CON. In an attempt to account for inter-group height differences, areal DXA measurements were converted to apparent bone mineral density (BMAD). GYM had significantly (P<0.05) greater femoral neck (0.698 ± 0.058 vs. 0.648 + 0.064 g.cm⁻²) and trochanteric (0.616 ± 0.060 vs. 0.530 + 0.084 g.cm⁻²) BMD. Additionally GYM had significantly greater whole body (0.101 ± 0.009 vs 0.094 ± 0.007 g.cm⁻³) BMAD than CON. GYM also had significantly greater total 367.75 ± 51.61 vs 307.37 ± 27.59 mg.cm⁻³), trabecular (207.93 ± 45.35 vs 163.76 ± 31.41 mg.cm⁻³) and cortical (496.94 ± 67.51 vs 429.80 ± 33.78 mg.cm⁻³) volumetric BMD than CON at the distal radius. There were no significant differences between mothers of GYM or CON for any of the variables studied. Significant daughter mother correlations existed only for lumbar spine BMD (r=0.55). These results suggest that participation in elite gymnastics prior to puberty elicits favourable whole body adaptations in bone mineral density, and also that striking regional differences are observed at the wrist, a site subjected to repetitive high impact loading during training. / Thesis / Master of Science (MSc)

Significant deposits of heavy mineral sands (primarily ilmenite and zircon) are located in Virginia in Dinwiddie, Sussex and Greensville counties. Most deposits are located under prime farmland, and thus require intensive reclamation when mined. The objective of this study was to determine the effect of four different mine soil reconstruction methods on soil properties and associated rowcrop productivity. Treatments compared were 1) Biosolids-No Tillage, 2) Biosolids-Conventional Tillage, 3) Lime+NPK fertilized tailings (Control), and 4) 15-cm Topsoil over lime+P treated tailings. Treated plots were cropped to corn (Zea Mays L.) in 2005 and wheat (Triticum aestivum L.) in 2006. Yields were compared to nearby unmined prime farmland yields. Over both growing seasons, the two biosolids treatments produced the highest overall crop yields. The Topsoil treatment produced the lowest corn yields due to relatively poor physical and chemical conditions, but the effect was less obvious for the following wheat crop. Reclaimed land corn and wheat yields were higher than long-term county averages, but they were consistently lower than unmined plots under identical management. Detailed morphological study of 20 mine soil pedons revealed significant root-limiting subsoil compaction and textural stratification. The mine soils classified as Typic Udorthents (11), Typic Udifluvents (4) and Typic Dystrudepts (5). Overall, mined lands can be successfully returned to intensive agricultural production with comparable yields to long-term county averages provided extensive soil amendment and remedial tillage protocols are implemented. However, a significant decrease (~25 to 35%) in initial productivity should be expected relative to unmined prime farmland. / Master of Science

The work seeks to reconsider aspects of high density in urban architecture, exemplified in a site in Hong Kong, where currently urban housing, temple, commercial, office and other structures coexist. While a very high density of urban housing is in place, it does not consider qualities of living such as natural light and view in the apartment layouts. In addition to qualities directly related to living, the thesis also seeks to engage a notion of identity and individuality which is often absent in high density projects. The stereotypical image of mediocre high-density environments is a relentless repetition of stacked units which accommodates only very basic human needs of cooking and sleeping but does not offer high quality urban spaces where people can expand their otherwise tight dwelling. The investigation seeks to recognize the particularities of the Hong Kong site, including a temple complex which offers itself as a unique and peaceful moment, contrary to the hustle and bustle of the city. The relationship between dwellings and temple is a point of departure which architecturally expresses a deep respect for culture and context of Hong Kong. A good architectural density in this sense is a composite of diverse function and spaces that offer opportunities of activities that together form a sense of place. / Master of Architecture / This thesis explores what a reconsidered density in a city could benefit the immediate environment and offer a better living quality for the residents.

The Rayleigh-Taylor instability (RTI) is one of the primary hydrodynamic instabilities that acts as a disputer to achieving high yield inertial confinement fusion (ICF). The potential for RTI to grow on the interior surface of ICF capsules, caused by deceleration during the implosion, further emphasises the need to better understand the seed mechanisms for RTI and possible mitigation methods for damping the instability growth. Reducing the growth of RTI during deceleration could preserve the spherical symmetry of ICF implosions and reduce the amount of mix between the solid capsule liner and fuel hot-spot. Additionally, it has been shown that magnetic fields do damp RTI growth, and the presence of a magnetic field lowers the threshold for achieving fusion and increases the yield. Understanding the seed mechanisms of the RTI, especially on the interior surface of ICF capsules, further allows for better understanding of the morphology of the RTI growth dur- ing deceleration. Classically RTI has been studied using single or multi-mode sinusoidal perturbations, which result in bubble and spike morphology. However in addition to si- nusoidal perturbations, single-feature perturbation, such as voids or divots, can seed RTI. This form of RTI is considered the thin-layer RTI, where the perturbation's wavelength is longer than the dense layer's thickness. This specific RTI evolution results in a morphology consisting of a single central spike and arms that extend horizontally away from the spike and eventually fall back towards the interface. Thin-layer RTI is important to explore dur- ing deceleration due to the presence of the fill-tubes in ICF capsules causing holes in the shell. Creating experimental platforms for current laser configurations on Omega and the Na- tional Ignition Facility (NIF) is necessary to study deceleration-stage RTI experimentally and validate computational modeling. A comprehensive exploration of potential experimen- tal designs on Omega, Omega-EP, and NIF are explored to identify a platform with which deceleration-stage RTI can be studied with and without the presence of an externally applied magnetic field. Additionally, the design of a novel experimental platform for Omega-EP to study thin-layer RTI during deceleration with and without an externally applied magnetic field is presented, along with data collected during the first experiments performed utilizing the platform. Lastly, a first of it's kind RTI platform for NIF is fielded and the results are presented, including an exploration of the possible impacts high-intensity-laser generated hot-electrons can have on experimental targets. The results of these experimental platforms are used to benchmark computational models, and demonstrate the potential for magnetized RTI to be studied comprehensively in future experiments. / Doctor of Philosophy / The potential of controlled sustained nuclear fusions as a viable energy source has rapidly become a reality in recent years. Monumental progress has been made in the pursuit of con- trolled fusion, including the repeated achievement of fusion ignition at the National Ignition Facility (NIF), meaning there was successful production of more energy from the fusion reac- tion than laser energy used to trigger the reaction. However, in order for fusion to become a truly viable energy source improvements in capsule design and the mitigation of disruptions, like hydrodynamic instabilities, must be explored to produce higher energy yields. The Rayleigh-Taylor instability (RTI) is one of the most detrimental hydrodynamic insta- bilities in inertial confinement fusion (ICF). RTI occurs when a lighter fluid, like the fuel used in fusion reactions, supports a heavier fluid, the ICF capsule itself, under the influence of gravity. An ICF capsule is imploded, induced by the driving mechanism, such as a laser, but once the driver stops the capsule will begin to decelerate. During this deceleration stage, the interior surface of the ICF capsule in susceptible to RTI growth causing the cold capsule material to mix with the hot fusion fuel. This mixing reduces the fuel's ability to reach the necessary temperatures and densities need to achieve ignition and produce high energy yields. As a result, it is crucial to better understand the defects that cause RTI to grow and explore methods that could damp the RTI growth and preserve the integrity of the implosion and fusion fuel. The work presented here focuses on exploring both the seed mechanisms for RTI and miti- gation strategies. Specifically, using an externally applied magnetic field has been shown to damp RTI growth and in know to lower the threshold of the conditions needed to achieve ignition. A study of possible experimental setups at both the Omega laser and NIF is ex- plored in order to identify a design with which the damping effects of an externally applied magnetic field on deceleration-stage RTI can be studied experimentally. From this design study platforms for the Omega-EP and NIF were conceptualized and ultimately fielded. The results from these novel experiments are presented, along with an exploration of pos- sible effects on RTI unexpected preheating of the experimental targets. Additionally, an exploration of the seed mechanisms of RTI is presented with a look at the classic sinusoidal perturbation as well as using a divot to seeded thin-layer RTI, which evolves with a spike and arm morphology rather than the classical bubble and spike. The experimental results from Omega-EP using a divot as the perturbation are presented. Novel results of varying RTI platforms and their potential for further development provide crucial insight into the possible presence of deceleration-stage RTI in ICF capsules and can be iterated on in the future to further explore RTI evolution and damping methods.