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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

An evaluation of individualized instruction as used in the Accelerated Christian Education curriculum in Plateau State, Nigeria

Shaba, Christiana Oluleye 11 1900 (has links)
The dissertation is focused on exploring the aspects of the Accelerated Christian Education curriculum that shows its individualized nature. The aim of the study was to explore individualized instruction from the view of the ACE program with a view of possible recommendation for use on a wider scale in Nigerian schools. This was considered because of the several lapses identified in the present Nigerian education program. The research explored other teaching and learning methodologies to establish commonality and assess if indeed the programs form of individualization is related to any existing form. Interviews were conducted to get the experiences of students and supervisors who are using the program. Recommendations were made for consideration to the users of the program on the strengths and weaknesses examined and suggestions for possible improvement given based on the responses of the research participants. / M. Ed. (Didactics)
72

The hydrogeological impacts of longwall coal mining-induced susidence, northern Wasatch plateau, Utah : a modular, three- dimensional, finite-difference flow model

Herron, Steven K. January 1996 (has links)
the ground-water system was studied in Burnout Canyon, Northern Wasatch Plateau, Utah to provided hydrogeologic information relative to the impacts of longwall coalmining induced subsidence. The longwall panels of coal are overlain by approximately 600 feet of interbedded sand, silt, and shale. The water-bearing zones are comprised of local 1enticular sand lenses. Well analysis and locations of springs indicated that multiple ground-water systems are operating within the study area.A modular three-dimensional, finite-difference flow model (MODFLOW) was used to simulate the multiple water-bearing zones and associated hydrostratigraphy above the mine. The model was used to assess the distribution of head over space both pre- and post-subsidence, using absolute heads and measured values of mine-inflow for model calibration. Longwall retreat was simulated with two model runs, each representing a new face position. Model calibration indicated that spatial head distributions were affected by subsidence. / Department of Geology
73

The Role of Salmon in Middle Snake River Human Economy: The Hetrick Site in Regional Contexts

Manning, Cassandra R. 01 January 2011 (has links)
On the Columbia Plateau, the origin of the Winter Village Pattern has long been a focus of research. Intensification of resources such as salmon, roots, and local aquatic resources is often cited as the cause of declining mobility. To address this question in the middle Snake River region, I have re-analyzed fish remains from the Hetrick site (10WN469; Weiser, ID), with occupations spanning the Holocene. Expectations from foraging theory and paleoclimate data are used to address whether salmon and other fish use changed over time and if such changes are correlated with the development of the Winter Village Pattern. The results of my research indicate that there is no correlation between the timing of increased salmonid use at the Hetrick site and paleoclimatic change or the earliest evidence for the Winter Village Pattern. Further, these results are very similar to patterns of fish use seen at other sites on the Snake River, particularly those from the Early and Middle Holocene.
74

Lions on small reserves : an evaluation of ecological impact and financial viability

Erasmus, Wayne Norman 31 July 2008 (has links)
A founder population of lion (Panthera Leo) was introduced into a 70 km² privately-owned, wildlife reserve in the Waterberg area of South Africa. The lion and prey species' populations were monitored between 2001 and 2004. In this period, 452 kills were recorded at a mean kill rate of one kill every 2.43 days. The lions killed 11 common prey species. Eland, warthog, kudu, wildebeest and zebra comprised 75 % of the lion's diet. The lions consumed an average of 8 % of the available common prey species population per annum. Initially, the mean ungulate population growth rate was 30.9 %, but this rate declined to -0.8 % during the study period. Significantly more animals were killed in open habitats than in closed habitats. The loss in game value for the study period was over one million Rand. A formula was compiled to quantify the cost versus return aspects of introducing lion. / Nature Conservation / M. Tech. (Nature Conservation)
75

Interpreting Low-Temperature Thermochronology in Magmatic Terranes: Modeling and Case Studies from the Colorado Plateau

Murray, Kendra Elizabeth January 2016 (has links)
Robust interpretations of rock thermal histories are critical for resolving the timing and rates of geologic processes, especially as low-temperature thermochronology has become a common tool for investigating the evolution of landscapes and mountain belts and the feedbacks between geodynamic processes. Most interpretations of thermochronologic cooling ages, however, attribute rock cooling entirely to rock exhumation - a common but tenuous assumption in many settings where thermochronology is used to investigate links between tectonics, climate, and landscape evolution, because these places often have history of magmatism. Exploring the complexities - and advantages - of interpreting low-temperature thermochronologic data in magmatic terranes is the principal theme of this work. Using simple analytical approximations as well as the finite-element code Pecube, we characterize the cooling age patterns inside and around plutons emplaced at upper and middle crustal levels and identify the advective and conductive scaling relationships that govern these patterns. We find that the resetting aureole width, the difference between reset and unreset cooling ages in country rocks, and the lag time between pluton crystallization age and pluton cooling age all scale with exhumation rate because this rate sets the advective timescale of cooling. Cooling age-elevation relationships in these steadily exhuming models have changes in slope that would masquerade as changes in exhumation or erosion rates in real datasets, if the thermal effects of the plutons were not accounted for. This is the case both in the country rocks immediately next to upper crustal plutons and, surprisingly, in the country rocks kilometers above mid-crustal plutons with no surface expression. Together with a lag-time analysis useful for the practical question of when it is appropriate to interpret a cooling age as an exhumation rate in crystalline rocks, this work improves our framework for evaluating the effects of magmatism on thermochronologic datasets. We also demonstrate the importance of considering the magmatic history of a region in field studies of the Colorado Plateau, where interpreting apatite (U-Th)/He data requires diagnosing significant inter- and intra-sample age variability. Prior to considering the thermal history of the region, we develop a new model for a common source of this age variability: excess He implantation from U and Th (i.e., eU) hosted in secondary grain boundary phases (GBPs), which can make very low eU apatites hundreds of percent 'too old'. Samples significantly affected by He implantation are not useful for thermal history interpretations, but this model does provide a diagnostic tool for discriminating these samples from those with useful age trends. Once the effects of GBPs have been accounted for, the remaining data from two different thermochronologic archives in the central Colorado Plateau provide a new perspective on the Cenozoic history of the region, which has a multiphase - and enigmatic - history of magmatism and erosion. We find that sandstones in the thermal aureoles around the Henry, La Sal, and Abajo mountains intrusive complexes were usefully primed by magmatic heating in the Oligocene to document the subsequent late Cenozoic history of the region more clearly than any other thermochronologic archive on the Plateau. These data document a stable Miocene landscape (erosion rates<30 m/Ma) that rapidly exhumed ~1.5-2 km in the Plio-Pleistocene (~250-700 m/Ma no earlier than 5 Ma) in the Henry and Abajo mountains, and strongly suggest most of this erosion occurred in the last 3-2 Ma. The integration of the Colorado River ca. 6 Ma, which dropped regional base-level, is the principal driver of this erosion. It is likely, however, that a component of the rapid Pleistocene rock cooling is unique to the high mountains of the Colorado Plateau and reflects an increase in spring snow-melt discharge during glacial periods. Although apatite thermochronology results far from the Oligocene intrusive complexes cannot resolve this detailed Plio-Pleistocene history, they do constrain the onset of late Cenozoic erosion to no earlier than ~6 Ma. Moreover, apatite cooling ages from these rocks also document Oligocene cooling (ca. 25 Ma) that is contemporaneous with the emplacement of the laccoliths and the waning of the vigorous magmatic flare-up that swept through the southwestern USA ca. 40-25 Ma. Although the cooling ages are consistent with ~1 km of exhumation in the late Oligocene and early Miocene, as previous workers have suggested in the eastern Grand Canyon region, we demonstrate that a transient change in the geothermal gradient (peaking at ~50˚C/Ma in the late Oligocene) driven by moderate mid-crustal magmatism can produce identical age patterns. Therefore, we re-interpret the mid-Cenozoic erosion event on the Colorado Plateau as primarily a change in the crustal thermal field, rather than an erosional event. This requires a more significant Laramide-age unroofing in parts of the central Plateau and perhaps a re-evaluation of the interpretations of Oligocene canyon cutting in the Grand Canyon region
76

Age and Tectonic Evolution of the Amdo Basement: Implications for Development of the Tibetan Plateau and Gondwana Paleogeography

Guynn, Jerome January 2006 (has links)
The elucidation of the geologic processes that led to the creation of the Tibetan Plateau, a large area of thick crust and high elevation, is a fundamental question in geology. This study provides new data and insight on the geologic history of central Tibet in the Jurassic and Cretaceous, prior to the Indo-Asian collision, as well as the Gondwanan history of the Lhasa and Qiangtang terranes of the plateau. This investigation is centered on the Bangong suture zone near the town of Amdo and I present new geochronology, thermochronology, thermobarometry and structural data of the Amdo basement, an exposure of high-grade gneisses and intrusive granitoids. Using a range of thermochronometers, I show there were two periods of cooling, one in the Middle-Late Jurassic after high-grade metamorphism and a second in the Early Cretaceous. I attribute Middle-Late Jurassic metamorphism, magmatism, and initial cooling of the Amdo basement to arc related tectonism that resulted in tectonic or sedimentary burial of the magmatic arc. I propose that a second period of cooling, nonmarine, clastic sedimment deposition and thrust faulting in the Early Cretaceous is related to the Lhasa-Qiangtang collision. The thermochronology reveals limited denudation between the Cretaceous and the present, indicating the existence of thickened crust when India collided with Asia in the early Tertiary. U-Pb geochronology of the orthogneisses and detrital zircon geochronology of metasedimentary rocks suggests that the Lhasa and Qiangtang terrane were located farther west along Gondwanan's northern margin than most reconstructions depict.
77

Genetic Differentiation of the Geomys Pocket Gopher Complex of Texas

Block, Scott B. (Scott Bishop) 08 1900 (has links)
Genetic variation was analyzed for populations of seven taxa comprising four cytotypes of the Geomys bursarius chromosome complex, including G. b. major, G. b. knoxjonesi, and the Edwards Plateau taxa, G. b. llanensis and G. b. texensis. Genetic relationships of the Edwards Plateau gophers with other taxa and between themselves were examined. Genetic similarity, number of fixed allelic differences, and ectoparasite distribution indicate the Edwards Plateau gophers are a distinct gene pool. Isolation of the Edwards Plateau taxa precludes contact zone analysis. However, genetic differentiation is typical of that between other species of Geomys, and the Edwards Plateau taxa should be recognized as G. texensis. Distributions of allelic frequencies indicate little justification in retaining the subspecific status of the Edwards Plateau forms.
78

Vectors and transmission routes of animal trypanosomiasis on the Jos Plateau north central Nigeria

Olaniyan, Oluwashola January 2016 (has links)
Tsetse flies, Glossina species, are the biological vectors of Trypanosoma species which cause animal African trypanosomiases (AAT) in livestock (especially cattle) in sub-Saharan Africa. This disease is often fatal without treatment and negatively impacts on rural, agricultural and economic development. On the Jos Plateau, north central Nigeria, AAT was historically of little significance due to the presumed absence of tsetse and Fulani pastoralists were encouraged to settle there. But over the last 30 years, the disease has become widespread and highly prevalent in the area. This has been attributed to the expansion of tsetse on the plateau, frequent migrations of cattle to areas with higher tsetse densities and the presence of other biting flies which serve as mechanical vectors. In the current study, the presence and abundance of tsetse was determined in selected villages using biconical tsetse trap surveys. The low number of flies trapped suggests that tsetse expansion has been very limited within the plateau but the fact that trypanosome DNA was present in over half of these flies implicates them in AAT transmission. The migration of a herd of cattle was also tracked and during the period, blood samples were collected from the cattle and examined for trypanosomes using molecular techniques. Despite prophylactic treatment and deltamethrin sprays, results showed that a significant proportion of the animals (52%) had become infected with T. vivax over the migration period. Tsetse flies (G. palpalis) were also slightly more abundant in some of parts of the migration area. Potential mechanical vectors (Stomoxys spp. and Tabanidae) were trapped and results obtained from the examination of their mouthparts for trypanosomes indicate their involvement in transmission. However, it is difficult to make any definite conclusions about their overall contribution which is thought to be minimal and more studies are needed to clarify their significance. It is concluded that trypanosomiasis risk from tsetse on the Jos Plateau is currently low and seasonal migration appears to be the main driver of AAT transmission by exposing cattle to more tsetse for longer periods. Other biting flies may play a limited role which remains undetermined. Continued monitoring of cattle and tsetse across the plateau over the next few years is important and the careful use of trypanocides and insecticide treated cattle is recommended as an appropriate control strategy.
79

Experimental studies thermally of ecological building in Loess Plateau areas of China.

January 2006 (has links)
Mu Jun. / Thesis submitted in: December 2005. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 181-183). / Abstracts in English and Chinese. / Chapter 1. --- Introduction --- p.1 / Chapter 2. --- Issues and Background --- p.5 / Chapter 2.1. --- Why Ecological Architecture? --- p.5 / Chapter 2.1.1. --- Fossil Fuels and Environmental Issues --- p.5 / Chapter 2.1.2. --- The Buildings' Role in the Issues --- p.9 / Chapter 2.2. --- Knowledge in Ecological Design --- p.11 / Chapter 2.2.1. --- About Ecological Architecture --- p.11 / Chapter 2.2.2. --- Thermal Study ~ A Significant Way to Ecological Architecture --- p.13 / Chapter 2.2.3. --- What is Suitable Ecological Architecture for Loess Plateau areas of China --- p.16 / Chapter 3. --- Defining the Future Ecological Architecture in Loess Plateau Areas --- p.20 / Chapter 3.1. --- Economy for Building --- p.20 / Chapter 3.1.1. --- Situation --- p.20 / Chapter 3.1.2. --- Technological Strategies towards a Cost-effective Ecological Approach --- p.22 / Chapter 3.1.3. --- Alternative-Technological Approach --- p.24 / Chapter 3.2. --- Climate --- p.25 / Chapter 3.2.1. --- Climatic Characteristics --- p.25 / Chapter 3.2.2. --- A climatically Responsive Approach ~ Selective Environmental Design --- p.32 / Chapter 3.2.3. --- Climatic Response of Thermal Design Guidelines --- p.33 / Chapter 3.2.3.1. --- Minimizing Heat loss through Building Fabrics --- p.34 / Chapter 3.2.3.2. --- Utilization of Available Natural Energy --- p.37 / Chapter 3.3. --- Benefits from Vernacular Architecture --- p.45 / Chapter 3.3.1. --- Earth ArchitecturéؤVernacular Architecture on Loess Plateau --- p.45 / Chapter 3.3.1.1. --- Classification --- p.46 / Chapter 3.3.1.2. --- Environmental Performance --- p.53 / Chapter 3.3.2. --- Literature Review of Studies on Earth Architecture --- p.58 / Chapter 3.3.2.1. --- Properties of Earth-based Materials --- p.58 / Chapter 3.3.2.2. --- Literature on Earth Architecture --- p.60 / Chapter 3.3.3. --- Issues and Development --- p.76 / Chapter 3.3.3.1. --- Limitation in Existing Earth Architecture of Loess Plateau --- p.76 / Chapter 3.3.3.2. --- Recent Research on Developing Earth Architecture in Loess Plateau Areas --- p.77 / Chapter 3.3.3.3. --- Considerations --- p.81 / Chapter 3.4. --- Conclusion --- p.82 / Chapter 4. --- Making of the Classroom as Designed for the Thermal Study --- p.84 / Chapter 4.1. --- Why a Classroom? --- p.84 / Chapter 4.2. --- The School Project and the Classroom Simulated --- p.85 / Chapter 5. --- Thermal Study by Simulating Experiments --- p.88 / Chapter 5.1. --- Research Methodology --- p.88 / Chapter 5.2. --- Program Validation --- p.89 / Chapter 5.3. --- Experimental Series of Simulation and Model Setup --- p.93 / Chapter 5.4. --- Thermal Mass and Insulation --- p.95 / Chapter 5.4.1. --- External Wall --- p.95 / Chapter 5.4.2. --- Roof Study --- p.97 / Chapter 5.4.3. --- "Windows, Doors and Glazing" --- p.100 / Chapter 5.4.4. --- Incorporated Performance --- p.103 / Chapter 5.5. --- Passive system for natural energy use --- p.106 / Chapter 5.5.1. --- Passive Solar System Study --- p.106 / Chapter 5.5.1.1. --- Wall-based Passive Solar System --- p.106 / Chapter 5.5.1.2. --- Roof-based Passive Solar System --- p.125 / Chapter 5.5.1.3. --- System Comparison in Thermal Performance --- p.135 / Chapter 5.5.2. --- Natural Ventilation System with the Heat Exchanger --- p.137 / Chapter 5.5.2.1. --- Pre-warming Effect of the Solar Space --- p.139 / Chapter 5.5.2.2. --- Effect of the Earth-air-tunnel --- p.142 / Chapter 5.5.2.3. --- Incorporation with the Chimney --- p.153 / Chapter 5.5.2.4. --- Comparison in Performance --- p.158 / Chapter 5.6. --- Summary --- p.159 / Chapter 6. --- Design Improvement and Performance Prediction --- p.162 / Chapter 6.1. --- System Incorporation and Design Improvement --- p.161 / Chapter 6.2. --- Thermal Performance Prediction --- p.167 / Chapter 7. --- Conclusion --- p.174 / Appendix --- p.179
80

Organizational Citizenship Behavior: A Career Development Strategy

Sutton, Martha J 14 January 2005 (has links)
The goals of the present study were to 1.) develop a model of career related factors that could be related to organizational citizenship behaviors (OCB); and 2.) determine if the proposed relationships between the career focused variables and OCB differed across rating source. A total of 262 volunteers from a Corporation and University completed a survey in either online or by paper and pencil that included demographics and measures of: job involvement, career motivation, occupational commitment, perceptions of career plateau, career stage, and OCB. Ratings of OCB were obtained from approximately 195 participant supervisors and/or coworkers. Correlational and multiple regression analyses showed that, as hypothesized, career motivation and job content plateau were related to self-ratings of OCB, explaining unique variance beyond that accounted for by the organization and select demographics. Coworker ratings of OCB were explained only by the organization, levels of education and, gender. A series of regression analyses showed that the majority of the relationships between the career variables and ratings of OCB were not moderated by perceptions of career plateau or career stage. The relationship between job involvement and coworker ratings of OCB, however, was moderated by the participants career stage. Participants in the primary career stages received higher ratings than those in the boundary stages on all three forms of OCB. Simple slope analyses showed that, in general, those in the primary and boundary stages who were more job involved received higher ratings of OCB. Coworkers may have attributed extra-role behaviors to participants job involvement, the most visible career factor. Finally, the relationship between career identity and participant ratings of OCBO was stronger than between identity and coworker ratings of OCBO. These findings provide practical and theoretical implications. Practically, the results suggest that organizations may influence the performance of OCB by recognizing and working with those who are career motivated and by ensuring that all employees are challenged by their jobs. Theoretically, this research provides evidence that OCB may be an alternative and viable career strategy employed by career motivated employees.

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