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    Nerve growth factor: its role in male fertility as an ovulation inducer

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    The studies presented in this thesis were designed to elucidate whether the abundance of ovulation-inducing factor/nerve growth factor (OIF/NGF) in alpaca semen can be used as a biomarker to predict male fertility. The neurotrophin, OIF/NGF has been identified in camelid, cattle and human semen. It is only in camelids, however, that an ovulation-inducing role for OIF/NGF has been described. The information gathered from several studies clearly demonstrate that this protein is the stimulus responsible for initiating the ovulatory cascade in camelids. In addition, intramuscular administration of OIF/NGF resulted in a dose-dependent response in terms of ovulation rate, corpus luteum (CL) lifespan, luteinizing hormone (LH) and progesterone secretion. I hypothesized that the quantity of OIF/NGF differs among male alpacas and this abundance arbitrates ovulation and pregnancy rates as well as CL formation and function. To substantiate this hypothesis, the following questions were answered: 1) can OIF/NGF in alpaca semen be quantified using a radioimmunoassay; 2) does the concentration and total abundance of OIF/NGF in alpaca semen vary within and among male ejaculates; 3) what is the glandular source of OIF/NGF that contributes to the male ejaculate; 4) is OIF/NGF concentration or abundance related to parameters associated with male fertility; 5) can OIF/NGF concentration or total abundance in the ejaculate discriminate fertile and subfertile males using both retrospective and prospective approaches; and 6) can power Doppler ultrasonography be used to assess the luteotrophic effect of OIF/NGF in tissue vasculature of the developing CL? I discovered that the source and the amount of OIF/NGF varies among species. In llamas, OIF/NGF is produced by both the corpus and disseminate portions of the prostate gland. In rats, OIF/NGF was detected in testis interstitial cells and in the lumen of the coagulating gland (anterior prostate). Ovulation-inducing factor/NGF secretion by the ampullae and vesicular glands contributed to its presence in bull (cattle and bison) ejaculates. In elk and white tail deer, OIF/NGF was detected in the ampullae and prostate glands, respectively. To gain an understanding of the abundance of OIF/NGF in ejaculates and changes in its concentration within and among males, OIF/NGF levels in semen were quantified using the radioimmunoassay. The assay developed exhibited parallel displacement curves among recombinant NGF, OIF/NGF purified from llama seminal plasma, llama and bull (cattle) seminal plasma. Ovulation-inducing factor/NGF comprised a greater percentage of the total protein found in camelid ejaculates than in cattle. Ovulation-inducing factor/NGF concentration correlated positively with sperm concentration and negatively with pH and semen volume, while total abundance of OIF/NGF was related to total prostate area and OIF/NGF concentration. Although a correlation was found between sperm concentration, neither OIF/NGF concentration nor total abundance was associated with higher ovulation, pregnancy or live birth rates. A clear association of the quantity of OIF/NGF in the male ejaculate at breeding and CL form and function was not evident. The measurement of CL vasculature by power Doppler ultrasonography, however, was able to determine nonpregnancy in alpacas earlier than the assessment of changes in CL diameter. In summary, my results did not support the hypothesis that the measurement of OIF/NGF concentration or total abundance in alpaca semen can be used to predict fertility in male alpacas

    Out-of-plane behaviour of concrete block walls with unbonded reinforcement

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    The use of grout in conventional reinforced masonry construction increases the cost and time of construction but, when used in combination with reinforcing steel, allows walls subject to out-of-plane loads an enhanced ability to span between lateral support levels. Reinforced concrete block walls constructed in this manner can typically span at least two stories in constrast to the limited single storey capacity of unreinforced walls. However, the use of grout as needed for the construction of these walls increases their self-weight, and requires an additional trade on-site. A novel, potentially cost-efficient, approach to achieve reasonable load-carrying capacity in masonry walls was therefore investigated that involves the use of minimally stressed reinforcement anchored at the top and bottom of the wall. This allows for a grout-free structural system that relies upon arching to resist the flexural effects resulting from out-of-plane loads and so make more effective use of the compressive capacity of the masonry assembly. An experimental program was therefore conducted at the University of Saskatchewan to investigate the performance of concrete masonry block walls reinforced with non-prestressed, unbonded reinforcement. This study included a total of 21 walls that were built to identify potential alternatives to unreinforced and conventionally grouted and reinforced walls. The strength and serviceability of these walls was evaluated. All walls in this program were two and a half blocks wide and 14 courses tall and were built in running bond using standard 200 mm concrete blocks. Six replicates of both unreinforced and partially grouted, conventionally reinforced walls served as control specimens. An analysis of the data obtained during testing revealed that the walls with unbonded reinforcement were inherently stable with maximum loads approaching those of partially grouted, conventionally reinforced walls. Furthermore, an analytical approach is presented herein that is based on the assumption that the walls with unbonded reinforcement could be modeled using a three hinged mechanism. The analytical model was found to match with the experimentally obtained load versus mid-height deflection data reasonably well throughout the post-cracking range

    An Investigation of the Electronic and Catalytic Properties of Ceria Nanocubes

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    The focus of this thesis was on the synthesis, characterization and application of ceria nanocubes. This thesis is divided into two main sections; the first section investigates the electronic properties of ceria nanocubes, and the second explores their catalytic applications towards alcohol oxidation reactions. The first project of this thesis consisted of the X-ray characterization of hydrothermally synthesized ceria nanocubes of various sizes. For the first time, the electronic properties of such nanocubes were systematically studied using high resolution XPS and XANES. It was found that the concentration of Ce3+ present within the nanocubes was independent of the particle size, as well as the Ce precursor used during synthesis. Throughout the analysis of the Ce 3d and 4d XPS spectra, it was observed that the surface of the ceria nanocube samples was undergoing photoreduction/damage over time. This damage was attributed to the samples’ exposure to high intensity X-ray radiation. This was confirmed through examination of the Ce M4,5- and N4,5-edge XANES spectra. From these results, it was clear that the concentration of Ce3+ on the surface of the ceria nanocubes was independent of particle size. This fact may become important when investigating their potential catalytic activity. The second project of this thesis concentrated on the analysis of the catalytic activity of a variety of CeO2, Au and Au/CeO2 catalysts towards the oxidation of benzyl alcohol. The low temperature oxidation reactions were studied using 1H NMR spectroscopy. It was observed that Au NPs, Au/bulk CeO2, and Au/CeO2 nanocubes in water and K2CO3 were active catalysts for this oxidation reaction at 60°C in both air and O2 (g) atmospheres. Surprisingly, however, the Au/bulk CeO2 and Au/CeO2 nanocube catalysts showed very similar activities. It was also found that ceria nanocubes alone, and Au25(SR)18/bulk CeO2 showed no activity for this reaction under similar conditions. It was determined that below a substrate to catalyst ratio of ~ 1500:1, the Au/CeO2 catalysts, which showed the highest activities, were mass-transport limited with respect to the O2 in the system. The turnover frequencies of the supported catalysts were approximately double those of the unsupported NPs. Furthermore, these reactions have indicated that activating Au25(SR)18/CeO2 for catalysis is a non-trivial task, and more work needs to be done to understand the activation of such clusters

    Real-time monitoring of a multiple retrogressive landslide

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    In this thesis the data collected from the field monitoring of slope inclinometers, in place inclinometers (IPIs) and vibrating wire piezometers (VWPs) installed in a multiple retrogressive landslide are evaluated and re-interpreted. The goal of this research was to evaluate the IPIs in particular, as part of a real-time slope stability monitoring system. The real-time monitoring system was installed by the Saskatchewan Ministry of Highways and Infrastructure (SMHI) to monitor a multiple retrogressive landslide affecting Highway No. 302 near Prince Albert, Saskatchewan. The instrumentation was connected to an automatic data collection and communication system so that data was available remotely via the ARGUS monitoring website. The instrumentation system was implemented after manual displacement monitoring confirmed high rates of movement. The automated landslide monitoring system utilized IPIs and VWPs. The instruments were installed next to Highway No. 302 at the crest of the slope and next to the North Saskatchewan River at the toe of the slope. Data was collected between September 18, 2005 and July 2, 2006. The near real-time data provided from the instrumentation was pore water pressure, river level, and lateral slope displacement at an hourly interval. Site investigation and slope inclinometer monitoring confirmed a major slip surface located in the glaciolacustrine clay deposit just above the clay/till contact. Slope inclinometer monitoring showed that the toe of the slope was moving at greater rates and magnitudes than the crest of slope. This observation of movement was consistent in the literature regarding other multiple retrogressive landslides using manual methods of monitoring. The installation of the automated monitoring system allowed instrument data to be collected at hourly intervals. Consistent periodic reading intervals captured data from the IPIs that showed the crest of the slope was moving more quickly than the toe. This was a significant observation that may not have been captured with manual readings with a traversing slope inclinometer probe. Observations were also made by correlating displacement data from IPIs at the toe of the slope with river level. It was shown that movement began after a rise and fall in river level. This suggests that displacement of the landslide was triggered by river bank erosion due to higher seasonal flows or alternately a rapid drawdown mechanism. On October 13, 2005, 25 days after installation of the IPIs, a major disturbance in the readings at both the crest and toe of the slope occurred. After this disturbance the crest was moving at greater rates than the toe. The initial disturbance was attributed to a settling of the head assembly of the IPIs triggered by global failure of the slope. Additional disturbances were noted in the IPIs at the toe of the slope and attributed to the casing contacting the IPIs. A geometric analysis was developed to verify that the unexpected movement could have been caused by the casing contacting the IPIs. The geometric analysis included observation of the shear induced deformation profile of the slope inclinometer casing, IPIs diameter, IPIs length and the annular space between the casing and the IPIs. The geometric analysis verified that the IPIs at the toe of the slope were likely affected by the IPIs coming into contact with the casing. Casing contact could affect the IPIs orientation and depth position, resulting in unexpected data. An additional set of IPIs data from a landslide near Aylesbury, Saskatchewan was used to compare to the IPIs data from Highway No. 302. Data comparison showed that there were erratic readings from the IPIs at the Highway No. 302 site while the IPIs at the Aylesbury site generally remained stable and consistent. This data also confirmed that the IPIs at Highway No. 302 were affected by casing contact. The near real-time monitoring system was an excellent risk management tool for SMHI. Due to the rate and magnitude of movement the instrumentation was destroyed sooner than expected. The data set produced allowed for evaluation of the landslide and performance of the IPIs. In conjunction with the river data the IPIs helped identify potential failure mechanisms. Additional work is required to ensure that the data from IPIs can be used to evaluate landslide kinematics. In particular ensuring that the IPIs are not used beyond their capability and providing realistic data

    Examining predictor variables on treatment outcome in the early skills development program

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    Saskatchewan Health has provided funding to Saskatoon and North Battleford District Health Boards to establish a school and home-based program for very aggressive kindergarten and grade one children. The purpose of the Early Skills Development Program is to assist young children who present with aggressive behaviours develop more socially acceptable interaction styles so they are less at risk for social rejection and/or neglect (Child and Youth Services, 2002). Pre- and post-intervention data was collected on each child that participated in the 10-week Early Skills Development Program using the Child Behavior Checklist- Teacher Report Form, which includes eight clinical scales: Withdrawn, Somatic Complaints, Anxious/Depressed, Social Problems, Thought Problems, Attention Problems, Aggressive Behavior, and Delinquent Behavior. In addition, demographic data was collected on each child, including age, grade, gender, diagnosis of a behaviour/mood disorder, medication status, number of siblings, family status, and whether the family is on social assistance. Evaluations of the efficacy of the Early Skills Development Program have been conducted at year one (Mykota, 1999), year two (Headley, 2000), and year three (Leibel, 2002) since the program’s commencement. Each study found statistically significant deceases in aggression overall. However, closer examination of individual children who participated revealed that several participants either had more significant decreases in aggressive behaviour or were not successful at all. The finding of some children showing greater improvement over others, or no improvement at all, suggests the need for examination of the predictive variables that affect treatment outcomes in the Early Skills Development Program. The objective of the following research studies was to determine, in three parts, what variables will predict treatment outcome in the Early Skills Development Program. Based on previous research (e.g., Dumas & Wahler, 1983; Kazdin & Crowley, 1997; Lochman et al, 1985) and the extant data available, three studies were conducted. Study one examined child demographic variables as they relate to the prediction of treatment outcome in aggressive behaviour. Results from study one indicated that the demographic variables available in the extant data base were not predictive of treatment outcome in the Early Skills Development Program. Study two investigated psychological variables, based on ratings on the Child Behavior Checklist-Teacher Report Form, in the prediction of treatment outcome. Results from study two indicated that children who showed symptoms of being withdrawn, having social problems, and the presence of anxiety and depression showed increased benefit from the Early Skills Development Program. Study three examined contextual variables that related to the child’s family in predicting the behaviour change of participants immediately following treatment in the Early Skills Development Program. Results indicated that participants who did not have any siblings at the time of treatment showed a significantly higher decrease in aggression than those who did have siblings

    Relationships among landform elements, soil properties, and crop yields on Blaine Lake-Hamlin Soils

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    Non-Peer ReviewedSoil properties are an important part of the complex framework in the crop production system. Soil properties may vary over short distances, but are related to position within the landscape. This study investigated the relationships among pH, salinity, bulk density, horizon thickness, depth to carbonates, and soil moisture according to landform position. Four catenas were studied under different crop rotations: summerfallow-canola-wheat, summerfallow-wheat-wheat, continuous cereals, and continuous cereals plus a legume. Total plant biomass and crop yields were determined on hand harvested samples from each slope position. Best yields in 1989, generally occurred in back and shoulder slopes and lowest yield in footslope areas that were flooded out by intense summer showers

    Simulating Areal Snowcover Depletion and Snowmelt Runoff in Alpine Terrain

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    An overwhelming proportion of the flow of some of the major rivers in the western Canadian Prairies (e.g., the South Saskatchewan River) is derived from runoff in the headwaters of the Rocky Mountains, where snowmelt represents the greatest single contribution. Increasing concerns over future regional water resource stresses require better understanding and prediction of some alpine snow hydrology components, which are currently limited due to the large spatial heterogeneity of snow accumulation and melt processes, and problems with the scaling of these processes in hydrological models. The work presented in this thesis was aimed at improving the representation and effects of this variability on simulated areal snowcover depletion (SCD) and snowmelt runoff generation at different spatial scales in alpine environments. To accomplish this, a focused field data collection campaign was carried out at a small (1.2 km2) alpine cirque basin within the Marmot Creek Research Basin in the Front Ranges of the Canadian Rockies in the Kananaskis Valley, Alberta. Measurements here included detailed hydro-meteorological observations, snowcover (spatially distributed snow surveys, LiDAR-derived snowcover mapping, and daily acquisition of terrestrial-based photography of the alpine landscape for spatial–temporal snowcover mapping), and streamflow measurement at the alpine basin outlet. A theoretical framework was developed to upscale physically based point-scale snowmelt simulations for the prediction of areal SCD and meltwater generation, and was based on the lognormal probability distribution for values of snow water equivalent (SWE). The framework was applied and tested using a point-scale snowmelt model (Snobal) developed within the Cold Regions Hydrological Model (CRHM) platform. Finally, a conceptual/process-based hydrological model was developed for this basin using CRHM, and the spatial snowmelt framework was used together with this model to simulate the streamflow hydrograph at the outlet of the basin. This work has led to a number of important findings that advance the state of understanding of alpine snow hydrology, and provide useful tools for prediction outside of well-studied research basins. First, it was shown how the spatial and temporal variability in both pre-melt snowcover and snowmelt energetics control the evolution of the alpine snowcovered area (SCA) during the spring, which is an important variable for both hydrological and climatological applications. Daily terrestrial photographs were re-projected orthogonally over the landscape, and comparison of model predictions of areal SCD with observations from this imagery showed that improvements resulted from considering separate SWE distributions and applied energy to the snowcover on different slope-based landscape units in the basin, relative to using a single, basin-wide distribution with uniform applied energy. It was further shown that at certain times, such as early in spring, the effects of differential warming, ripening, and melt of different initial classes of SWE within a single landscape unit cause an “acceleration” of areal SCD due to the earlier and more rapid melt of areas with a relatively shallow snowpack, and that models that do not properly account for this effect may be in error. This is a feature that is common to all “cold” snowcovers, yet currently this can only be represented by fully distributed simulations applied at a fine spatial scale (i.e., 10 – 25 m), and where difficulties arise in establishing initial snowcover patterns outside of well-studied basins. However, the framework developed here provides a useful approach for resolving all major sources of SWE and melt rate variability, while retaining spatial and computational simplicity, and physical integrity. This is done by making explicit snowmelt computations for different initial classes of SWE (with unique mass and energy states) on different slope-based landscape units; the framework only requires values of mean SWE and CV (coefficient of variation) to establish initial snowcover conditions in a model. Thus, it can easily be applied in other basins by using “representative” landscape-based CV values. Lastly, the work provided insight on how the variability in both pre-melt snowcover and meltwater inputs over the basin influence the snowmelt hydrograph at the basin outlet. Through a comparison of different approaches for representing snowcover, snowmelt, and lower basin forest canopy effects, it was shown that the best correspondence with observed hydrographs was achieved when explicitly accounting for the differential timing, location, and extent of source areas for snowmelt runoff. However, in many other cases realistic appearing hydrographs were obtained, but for the wrong reasons due to cancellation of model errors. The approach here maintains internal “correctness” of the alpine snow components, which is beneficial towards development and parameterization of other process components in hydrological models applied elsewhere in alpine landscapes. The results also showed that the effects of differential melt timing and rate over different SWE classes within a single landscape unit (i.e., inhomogeneous melt) did not become manifested in the overall hydrograph response, despite having an important influence on areal SCD. Thus, if the primary goal of model application is to predict the hydrograph only, then this effect can likely be neglected without serious errors

    Sencor demonstration

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    Non-Peer Reviewe

    Finding periods in the high mass x-ray binary stars of the magellanic clouds

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    High Mass X-Ray Binary Stars (HMXBs) are stars that contain one early-type main sequence or giant star and one of a black hole, neutron star or white dwarf. HMXBs in the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC) are instructive to study because both galaxies are metal poor in comparison to the Milky Way and they are fairly transparent to both optical and X-ray radiation. This allows a more complete study of the whole population, without the biasing effects of gas and dust that occur in our own Galaxy. The objective of this study was to find the periods of HMXBs in the LMC and SMC with known optical counterparts in the dataset acquired by the Robotic Optical Transient Search Experiment telescope. Two possible orbital periods were found for the objects XTE J0055-724 and RX J0101.3-7211 of 1724 days and 478 days, respectively. Continued observations are recommended to confirm the two periods

    Geochemical Characterization of Brown Chalcedony During the Besant/Sonota Period

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    Suitable lithic material for toolmaking is fairly common across the Northern Plains and often can be found within the glacial till that still blankets the area. However, high quality toolstone tends to be limited to specific and well-known quarry locations such as the Knife River flint quarries of North Dakota. Archaeologists have long identified high-quality brown chalcedony found in archaeological sites as Knife River flint (KRF) based on a visual inspection. This material has been found throughout the Northern Plains region and is believed to have been a highly desired trade item. However, the discovery of local sources of high-quality brown chalcedony that is macroscopically identical to KRF has called into question whether this material was traded as widely as previously assumed. Samples of visually identical brown chalcedony from source locations across the Northern Plains, specifically Alberta, Saskatchewan, Manitoba, Montana, North Dakota, and South Dakota, along with KRF from the Primary Source Area in North Dakota, were collected in order to undergo geochemical characterization. This analysis was designed to determine if these source areas could be distinguished from one another and what elements aid in this differentiation. It was found that while similarities between a number of source locations exist, certain source areas such as the KRF Primary Source Area and source areas in Alberta, North Dakota and South Dakota can be distinguished from one another. For this reason further analysis into the archaeological implications of local varieties of high-quality brown chalcedony material were undertaken. The use of high-quality brown chalcedony seemed to have peaked during the Besant/Sonota time period (c. 2100 – 1100 BP) on the Northern Plains. Artifacts from well-known Besant/Sonota archaeological sites across Alberta, Saskatchewan, and Manitoba were selected to undergo geochemical characterization using laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS). This analysis has resulted in the discovery that local source areas of brown chalcedony were being exploited by Precontact groups rather than the KRF quarries in North Dakota. The implications of this are discussed in terms of trade and exchange relationships, ethnic/cultural landscapes, and economic efficiency


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