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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.
641

Puvaluqatatiluta, When We Had Tuberculosis: St. Luke's Mission Hospital and the Inuit of the Cumberland Sound Region, 1930–1972

Cowall, Emily S. 04 1900 (has links)
<p>This thesis explores the ethnohistory of Church- and State-mediated tuberculosis treatment for Inuit of the Cumberland Sound region from 1930 to 1972. Pangnirtung’s St. Luke’s Mission Hospital sits at the centre of this discussion and at the nexus of archival evidence and regional Inuit knowledge about tuberculosis. Triangulating information gained from fieldwork, archives, and a community-based photograph naming project, this study brings together the perspectives of Inuit hospital workers, nurses, doctors, and patients, as well as of Government and Anglican-Church officials, during the tuberculosis era in the Cumberland Sound.</p> <p>The study arose from conversations with Inuit in Pangnirtung, who wondered why they were sent to southern sanatoria in the 1950s for tuberculosis treatment, when the local hospital had been providing treatment for decades. Canadian Government policy changes, beginning in the 1940s, changed the way healthcare was delivered in the region. The Pangnirtung Photograph Naming Project linked photos of Inuit patients sent to the Hamilton Mountain Sanatorium to day-book records of St. Luke’s, and culminated in an emotional ceremony in 2009, during which copies of the photographs were returned to survivors or relatives.</p> <p>Information in hospital day books was used to map the yearly distribution of tubercular Inuit in traditional camps, which were progressively abandoned as Inuit in-migrated to Pangnirtung, in response to increased Government incursions and concerns about Arctic sovereignty. Contrary to the pattern for Canadian Arctic Inuit, more tubercular Inuit were treated locally at St. Luke’s than were sent away for treatment to southern hospitals on board the Government-commissioned medical-patrol ship, <em>CGS CD Howe</em>.</p> <p>This thesis underlines the importance of linking archival sources to local Inuit knowledge, in a collaborative, community-based research environment. It also speaks to current concerns about the re-emergence of tuberculosis and the importance of developing culturally-appropriate community initiatives to manage infectious diseases in Nunavut.</p> / Doctor of Philosophy (PhD)
642

User fee for wilderness recreation: a comparison of user characteristics and travel cost demand functions for Linville Gorge wilderness area and Grandfather Mountain backcountry, North Carolina

Cook, Philip S. January 1986 (has links)
User fees for federal Wilderness have been suggested as a way to reduce deficit spending on Wilderness recreation and supplement decreasing management budgets. This study examines the users of Linville Gorge Wilderness, a federal free area, and Grandfather Mountain Backcountry, a nearby private fee area, to determine if fees would exclude any socioeconomic or other user group who presently uses wilderness and determine if fees are acceptable to users. The study compares users' socioeconomic characteristics and travel cost demand functions and analyzes attitudes towards fees to determine the extent to which fees are likely to change use behavior. No difference is found in the socioeconomic characteristics of the users of the fee and the free area, suggesting fees excluding any for federal Wilderness are equitable, not excluding any socioeconomic group currently using Wilderness. The trip demand functions of the travel cost models for the two areas are statistically the same, suggesting users are making the same economic decision when visiting each area. Fees are found to be acceptable to users if Wilderness will deteriorate without fees and fee revenues are spent on Wilderness management. Users suggest about $25 for an annual Wilderness permit and about two dollars for a daily fee as reasonable amounts. Most users say the fee at Grandfather Mountain does not influence their decision to visit, suggesting fees will not greatly affect demand at federal Wilderness. The site demand function for Linville Gorge predicts a large decrease in demand, but this is common to most travel cost models and does not usually prove true. Further research of the travel cost model and the administrative feasibility of suggested fee levels is recommended. / M.S.
643

Incipient Motion Under Shallow Flow Conditions

Kanellopoulos, Paul M. 02 February 1999 (has links)
Laboratory experiments were conducted to investigate the effect of low relative depth and high Froude number on the dimensionless critical shear stress (Shields parameter). Spherical particles of four different densities and an 8mm diameter were used as movable test material. The relative depth ranged from 2 to 12 and the Froude number ranged from 0.36 to 1.29. The results show that the traditional Shields diagram cannot be used to predict the incipient motion of coarse sediment particles when the relative depth is below 10 and the Froude number is above 0.5, approximately. Experiments using glass balls, whose density is almost identical to that of natural gravel, show that the Shields parameter can be twice as large in shallow flows than in deep flows. The results also show that the Shields parameter is dependent on the density of the particles. Data obtained from other studies support the findings of the present work. These findings can result in significant cost savings for riprap. Additionally, velocity profiles using a laser-Doppler velocimeter (LDV) were taken for the glass ball incipient motion experiments. The purpose of this was to study possible changes in the velocity distribution with decreasing relative depth and increasing Froude number. The results show that the von Karman and integral constants in the law of the wall do not change in the range of relative depths and Froude numbers tested. / Master of Science
644

Regenerative Design Theory and Practice: A Demonstration of the Integrated Framework in a Resort Development at Mountain Lake, VA

Hodges, Nancy 24 July 2006 (has links)
The purpose of this thesis is to investigate the theory and practice of regenerative design and how the concepts apply to scales of design. Ultimately, it examines the applicability and limitations of these principles in a non-traditional resort development. The theories of John Lyle, Robert Thayer, and William McDonough are examined to assist in the establishment of a new framework for regenerative design which is can be used in the design process or evaluation. Case studies of the Center for Regenerative Studies, the Ford Rouge Plant and the Loreto Bay Resort were under taken to evaluate the success of current built works utilizing the new framework. Finally, the development of a regenerative resort community at Mountain Lake, in Giles County, Virginia, is undertaken as a vehicle to demonstrate the process of development and evaluation under the integrated regenerative framework. Regenerative design is a form of sustainable design which incorporates the interlocking of communities with the natural ecological cycles, the larger society and environmental costs. The overall goals for regenerative developments are to design communities which exist within natural limits and are interconnected to the regional society for needs outside the given site. Regenerative design incorporates diverse ecological, cultural, social and economical systems while maintaining their integrity within a dynamic whole. The integrated framework is an effort to direct site specific design through a flexible and extensive structure. There are two parts to this regenerative design framework. The first is a conceptual model for regenerative design, utilizing the existing idea of regenerative design rooted in sustainability, and overlays it with design driven elements of culture, experience, and education. The second element of the framework defines a set of strategies for the design process and a means of evaluating a design. / Master of Landscape Architecture
645

Spatial Patterns on Virginia's Second Highest Peak: Land Cover Dynamics and Tree Mortality in Two Rare Ecosystems

Harris, Ryley Capps 12 June 2020 (has links)
Whitetop Mountain is Virginia's second highest peak and hosts two globally rare, insular ecosystems: a southern Appalachian grass bald and a red spruce-dominated forest. These areas provide important ecosystem services and habitat for rare and endangered species. They are highly prized for their cultural value and recreational areas that support nearby rural economies. This thesis investigated spatial patterns in both ecosystems on Whitetop. We documented a 24.73% decrease of in the extent of the southern Appalachian grass bald across 68 years through analysis of historical aerial photography. In the red spruce-dominated forest, we used a consumer grade unmanned aerial vehicle (UAV) to survey the health of all trees within a 46 ha sample plot. We assessed (dead, dying, healthy) over 9,000 individual trees based on visual patterns in the imagery and produced spatial products that will inform land managers about where resources are most needed. About 7.4% of the red spruce trees in our study area were classified as dead or dying. A model relating spruce mortality to biophysical landscape factors identified no single predictive factor related to mortality. The addition of optical information from the UAV imagery into the model proved utility for remotely-sensed data in identification of dead spruce within the forest canopy at Whitetop and possibly in other similarly structured forests. This research contributed to the limited body of knowledge surrounding the decline of both southern Appalachian grass balds and red spruce forests and provided technical insights for future mortality monitoring. / Master of Science / This thesis investigates land cover changes in two rare ecosystems on Whitetop Mountain, Virginia. The mountain has important biological significance and is a cultural landmark. The high-elevation summit hosts plant and animal species characteristic of northern climates, including a red spruce-dominated forest and a southern Appalachian grass bald. This work documented a 24.73% decrease in the size of the rare southern Appalachian grass bald ecosystem at Whitetop Mountain over 68 years and discussed potential drivers and proposed management for conservation. We also successfully used a camera-equipped unmanned aerial vehicle (drone) to produce high quality imagery for spruce mortality detection within the red spruce forest. Of over 9,000 standing spruce trees, 7.4% were categorized as either dead or dying. We built a predictive model to investigate the relationship between mortality and biophysical environmental factors, but did not identify a single causal factor. A second model that included the color band information from the drone camera revealed that different types of aerial imagery could play a valuable role in detection of tree mortality in forests of similar structure. Overall this research contributes to the body of knowledge surrounding the decline of both southern Appalachian grass bald and red spruce ecosystems and provides insights for management.
646

Seasonal Reindeer Grazing Effects on Mountain Birch Forests : A 3D Perspective using Drones

Abderhalden, Bigna Lu January 2024 (has links)
Reindeer are important drivers of ecosystem processes in arctic and subarctic ecosystems, changing nutrient conditions and influencing vegetation by grazing and trampling. Mountain birch forests are one of the ecosystems impacted by reindeer grazing, but the effect on the 3D structure of these forests is not well understood. Drones are revolutionising ecological studies, allowing to create high-resolution 3D point clouds at low costs. I investigated the effect of year-round and autumn reindeer grazing on mountain birch forest vegetation in historically separated grazing areas at the Finnish-Norwegian border, using a combination of field data and drone data. The two sampling techniques were further compared to evaluate the possibility to use photogrammetric point clouds to characterise mountain birch forests. I found lower productivity in the year-round grazing regime, coinciding with generally higher vegetation density. Vertically, higher densities were found above browsing height, while the understory showed lower densities compared to autumn grazed areas. These results suggest that mountain birches allocate more biomass to the canopy area, which can be direct or indirect grazing effects. Nevertheless, overall productivity is lowered by grazing indicating changes in vegetation biomass and composition. The point clouds generally matched field data, but the understory vegetation tended to be underrepresented, arising the question if found effects are ecological or technical. As this could not be disentangled, cautious interpretation of my results is required. I conclude that using photogrammetric point clouds is a promising technique for ecological studies, but needs further development to improve accuracy and reliability of results.
647

Linking Streamflow Trends with Land Cover Change in a Southern US Water Tower

Miele, Alexander 21 December 2023 (has links)
Characterizing streamflow trends is important for water resources management. Streamflow conditions, and trends thereof, are critical drivers of all aspects of stream geomorphology, sediment and nutrient transport, and ecological processes. Using the non-parametric modified Mann-Kendall test, we analyzed streamflow trends from 1996 to 2022 for the Southern Appalachian (SA) region of the U.S. The forested uplands of the SA receive high amounts of rain and act as a "water tower" for the surrounding lowland area, both of which have experienced higher than average population growth and urban development. For the total of 127 USGS gages with continuous streamflow measurements, we also evaluated precipitation and land change rates and patterns within the upstream contributing areas. Statistical methods (i.e., generalized linear models) were then used to assess any linkages between land cover change (LCC) and streamflow trends. Our results show that 42 drainage areas are experiencing increasing trends in their precipitation, and 1 is experiencing a negative trend. A total of 71 drainage areas are experiencing increasing trends in either their annual streamflow minimums, maximums, medians, or variability, with some experiencing changes in multiple. From our models, it is suggested that agricultural expansion is associated with increasing minimum streamflow trends, but increasing precipitation is also positively linked. With this information, water managers would be aware of which areas are experiencing changes in streamflow amounts from LCC or precipitation and could then apply this in planning and predictions. / Master of Science / Water availability is important for resources management. Streamflow is a measure of available surface water and is an important component in the hydrological cycle. Using the non-parametric modified Mann-Kendall test, we analyzed streamflow trends from 1996 to 2022 for the Southern Appalachian (SA) region of the U.S. The forested uplands of the SA receive high amounts of rain and act as a "water tower" for the surrounding lowland area, both of which have experienced higher than average population growth and city expansion. For the total of 127 USGS gages with continuous streamflow measurements, we also evaluated precipitation and land cover change rates within the area upstream of the gage (or drainage/contributing area). Statistical methods (i.e., generalized linear models) were then used to assess any linkages between land cover change (LCC) and streamflow trends. Our results show that 42 drainage areas are experiencing increasing trends in their precipitation, and 1 is experiencing a negative trend. A total of 71 drainage areas are experiencing increasing trends in either their annual streamflow minimums, maximums, medians, or variability, with some experiencing changes in multiple. From our models, it is suggested that agricultural expansion is associated with increasing minimum streamflow trends, but increasing precipitation is also positively linked. With this information, water managers would be aware of which areas are experiencing changes in streamflow amounts from LCC or precipitation and could then apply this in planning and predictions.
648

Channel Morphology and Riparian Vegetation Influences on Fluvial Aquatic Habitat

Kozarek, Jessica Lindberg 23 February 2011 (has links)
As public awareness of river degradation has grown in recent years, the number of stream restoration activities has increased dramatically. Anthropogenic influences at a range of spatial scales from watershed landuse to riparian vegetation management to local channel morphology can have hierarchical relationships to local (meso- and macro-) in-stream habitat characteristics. This research examined these influences first by examining the influence of complex channel morphology on meso-scale brook trout (Salvelinus fontinalis) habitat in Shenandoah National Park, VA, and then by examining the combined influence of watershed urbanization and riparian vegetation (100-200 m reaches) on stream temperature. Moving beyond one-dimensional (1D) averaged representations of fish habitat, this research explored the distribution of two-dimensional (2D) flow complexity metrics at the meso-habitat scale as explanatory variables for brook trout habitat preferences and as potential metrics to evaluate habitat restoration design. Spatial hydraulic complexity metrics, including area-weighted circulation and kinetic energy gradients, were calculated based on 2D depth averaged modeled velocity distributions in two 100-m reaches on the Staunton River. While there were no statistically significant correlations between kinetic energy gradients or area-weighted circulation and fish density, fish density was positively correlated to the percent of the channel dominated by protruding boulders. The structural complexity of areas with protruding boulders create complex flow patterns suggesting that flow complexity plays an important role in available brook trout habitat preferences at the local scale, although the 2D depth averaged model may not have adequately represented this complexity. The 2D distribution of flow characteristics was then investigated further to quantify areas of flow refugia (low velocity shelters) and the relationship between these areas, traditional measures of habitat quality, and fish biomass. Flow complexity in the vicinity of flow obstructions (in this case, boulders) was investigated further using patch classification and landscape ecology metrics. The relative influence of riparian vegetation on stream temperature (another important habitat characteristic) in urban and nonurban watersheds was investigated in 27 paired forested and nonforested reaches in PA, MD, and DE. Riparian vegetation and watershed-scale urbanization both influence stream temperature, which can have profound impacts on in-stream ecosystems. Generally, increased urbanization and removal of riparian forest influenced maximum stream temperatures resulting in higher maximum summer stream temperatures (up to 1.8°C); however, the influence of riparian forests (at at 100-200 m reach scale) decreased with increasing urbanization. Extreme maximum summer temperatures, which are a concern for aquatic biota, increased in both frequency and duration in urban nonforested reaches relative to forested reaches indicating that the addition of a forested 100-200 m long buffer partially mitigated these temperature extremes even in urban watersheds. Overall, changes to channel morphology and riparian vegetation had measurable local effects on stream habitat (temperature and hydraulic complexity) yet the implications of restoration efforts at the local scale on ecosystem services at a larger (km +) scale requires further study. / Ph. D.
649

Identification of Fold Hinge Migration in Natural Deformation: A New Technique Using Grain Shape Fabric Analysis

Rose, Kelly Kathleen 12 June 1999 (has links)
Partitioning of finite strains in different domains within the limb and hinge regions of a fold can be used to understand the deformation processes operative during fold formation. Samples taken from the limb and hinge regions of a gently plunging, asymmetric, tight, mesoscale fold in the Erwin formation of the Blue Ridge in North Carolina were analyzed to determine the deformation mechanisms and strains associated with the folding event. Rf/phi grain shape fabric analysis was conducted for each sample and used to calculate the orientation and magnitude of the final grain shape fabric ellipsoids. Flexural folding and passive-shear folding models predict that the highest finite strains will be recorded in the hinge of a fold. The highest grain shape magnitudes recorded in the North Carolina fold, however, lie along the overturned fold limb. The final geometry of many folds indicates that hinge plane migration processes are active during compressive deformation events. Numeric, conceptual, and analogue based studies have demonstrated the migration of fold hinges during deformation. However, documentation of these processes in field based studies is rare and limited to techniques that are frequently site specific. Methods proven successful in natural studies include the analysis of superposed folding; the migration of earlier hinge-related features such as fractures, cleavage planes, and boudinaged bedding planes; and the kinematic analysis of syntectonic pressure shadows. The magnitude and orientation of the grain shape ellipsoids calculated for the North Carolina fold indicate that rocks in the overturned limb were once located in the hinge of the fold. Subsequent noncoaxial deformation processes operative during folding resulted in the migration of the hinge to its present orientation and position. This relationship indicates that it is possible to use strain/shape fabric analysis as a test for hinge migration in folds, and that this technique may be more generally applicable in natural settings than previously proposed tests. / Master of Science
650

Orientations and magnitudes of paleostress in the Great Valley Province of northern Virginia

Vaughn, Ginger L. 25 August 2008 (has links)
Calcite c-axes and e-twin plane orientations were measured in both matrix cements and younger fracture fills from late Cambrian to Middle Ordovician age limestone samples taken from the NW and SE limbs of the Massanutten Syncline, located within the North Mountain thrust sheet. Paleostress magnitude estimates using the Rowe and Rutter (1990) twin density technique indicate a differential stress of 240±31 MPa for samples collected from both limbs of the syncline. Three distinct patterns of paleostress orientations (compression directions) have been detected in the samples; each pattern is observed on both the NW and SE limbs of the syncline. The first pattern, exhibited by calcite grains cementing late fractures, is characterized by a maximum of compression axes oriented sub-perpendicular to bedding possibly indicating either thrust sheet loading or stress refraction associated with folding. Samples in which calcite grains from both fracture fills and earlier matrix cements were measured are characterized by a bimodal distribution of compression axes—the first point maximum being oriented sub-perpendicular to bedding, the second maximum placing compression directions at low to moderate angles to bedding. Restoration of bedding to horizontal results in this second set of compression axes plunging to either the SE or NW, sub-parallel to the regional thrust transport direction. The third pattern, originating from early cements, places compression directions plunging to the NE-SW at angles which are sub-parallel to bedding. These compression directions do not seem to correlate with major tectonic movements or thrust sheet loading and may reflect stresses associated with either movement over lateral ramps or oblique thrusting. / Master of Science

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