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Evaluation of Spring Discharge for Characterization of Groundwater Flow in Fractured Rock Aquifers: A Case Study from the Blue Ridge Province, VAGentry, William Miles 22 January 2003 (has links)
Recent models of groundwater flow in the Blue Ridge Province suggest multiple aquifers and flow paths may be responsible for springs and seeps appearing throughout the region. Deep confined aquifers and shallow variably confined aquifers may contribute water to spring outlets, resulting in vastly different water quality and suitability for potable water supplies and stock watering. A new Low Flow Recording System (LoFRS) was developed to measure the discharge of these springs that are so ubiquitous throughout the Blue Ridge Province.
Analysis of spring discharge, combined with electrical resistivity surveying, aquifer tests, and water chemistry data reveal mixed shallow and deep aquifer sources for some springs, while other springs and artesian wells are sourced only in the deep aquifer. The technique is suitable for rapid characterization of flow paths leading to spring outlets. Rapid characterization is important for evaluation of potential water quality problems arising from contamination of shallow and deep aquifers, and for evaluation of water resource susceptibility to drought. The spring discharge technique is also suitable for use in other locations where fractured rock and crystalline rock aquifers are common. / Master of Science
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A JOURNEY TO THE CENTER OF THE ASTHENOSPHERE: A NUMERICAL EXPLORATION OF MAGMA PRODUCTION BENEATH MID OCEAN RIDGE AND SUBDUCTION ZONE SYSTEMSBurkett, Francesca C 01 May 2024 (has links) (PDF)
2-D numerical computer models based on thermodynamic and kinematic principles have become invaluable tools for simulating geodynamic processes at these systems. Numerical models have proven effective for allowing the examination and computation of multiple factors simultaneously, providing scientists with an important resource with which to study complex systems. Previously, for instance, numerical models have been used for examining different factors involved in magma production at subduction zones and mid ocean ridges by modelling the influence and interplay of factors such as the effect of hydration and the influence of the depth of the fault between the two plates on the melting (van Keken, 2003; van Keken 2008). Additional models have explored the thermal structure of subduction zones and its relationship to the processes involved at convergent boundaries, including magma production (van Keken, 2023a). Syracuse et al. (2010) used numerical models for subduction zones, creating thermal models that examined dehydration and melting in subduction zones with a variety of slab geometries, convergence velocities, ages and structures. Still others have shown that thermal structure affects melt production, formation of arc volcanoes, dehydration, and seismicity, modelling the effects of varying slab dip, plate convergence velocity, plate age, etc. (Syracuse et al., 2010; Hayes et al, 2018). However, none have yet utilized models to systematically investigate magma production at either subduction zones or mid-ocean ridges to specifically examine both batch and fractional melting with the combination of multiple controlling factors including slab dip, convergence rate, hydration, minerology, and slab age. This project investigated the processes surrounding magma production at subduction and mid-ocean ridge systems through the creation of a numerical model and utilization of the developed model to explore the effects of a multitude of parameters on fractional and batch melting, as well as investigated the incorporation of incompatible elements, and other processes of interest in subduction and mid ocean ridge systems.
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Avaliação da manutenção da dimensão de rebordo alveolar após enxerto aloplástico de composto ósseo de rícino pós-extração dental em rato, estudo radiográfico e histológico / Evaluation of ridge preservation after castor bean alloplastic polymer bone graft post-extraction sockets of rats a radiographical and histological studyCastro, Fernando Silva de 22 February 2006 (has links)
O objetivo deste trabalho é o estudo do comportamento do enxerto de composto ósseo de rícino e sua eficácia na manutenção do rebordo alveolar. Através de avaliações histológicas e radiológicas. A cicatrização após as extrações dentárias faz com que o osso da região entre em um processo de atrofia. Existem técnicas preventivas para manutenção das dimensões do sitio de extração. As técnicas podem ser: implantes dentários, regeneração óssea guiada, enxertos ósseos e estas técnicas combinadas. A técnica de enxerto ósseo se baseia na ocupação do espaço, pelo biomaterial. O composto ósseo de rícino se destaca entre os aloplásticos, pois é de origem vegetal e tem se mostrado eficiente biomaterial na área odontológica. Foram utilizados neste trabalho 19 ratos Wistar. Dezoito ratos tiveram o incisivo lateral esquerdo extraídos e quatorze deles receberam o implante de composto ósseo de rícino, formando o grupo experimental, estes foram divididos em dois períodos de sacrifício, 30 e 45 dias, assim como o grupo de controle que não recebeu nenhum tipo de tratamento. O último animal é o animal padrão ouro que serviu de exemplo de estrutura íntegra. Os animais foram mortos humanitariamente e tiveram os fragmentos teciduais removidos a fim de serem analisados histologicamente sob microscopia óptica. Foram feitas tomadas radiográficas em filme odontológico de perfil e ântero-posterior imediatamente após a extração e imediatamente após a morte. As peças anatômicas foram retiradas e processadas para confecção de lâminas. Foi comparado radiograficamente e histologicamente o reparo do alvéolo preenchido por composto ósseo de rícino de uso odontológico com reparo fisiológico de outro alvéolo de extração dentária preenchido apenas com o coágulo formado nos dois grupos experimentais. O resultado evidenciou a manutenção dimensão alveolar pós-extração dentária nos grupos que receberam o composto ósseo de rícino. A técnica de preenchimento mostrou ser eficiente, tendo como resultado uma diminuição mínima das dimensões do alvéolo pós-extração dentária. Neste presente trabalho a técnica de preenchimento de alvéolo com o enxerto de composto ósseo de rícino se apresentou eficaz na manutenção das dimensões do osso alveolar / The aim of this work is to study the behavior of the castor bean alloplastic polymer bone graft on ridge preservation. The dental extraction cicatrization process is an atrophy process. There are preventive techniques for maintenance of the dimensions of the alveolar ridge. These techniques are: dental implant, guided bone regeneration, bone graft and the combination of these techniques. The technique of bone graft is based on filling the space with the biomaterial. The castor bean alloplastic polymer bone graft surpasses the alloplastic because it is of vegetable origin and shown efficient biomaterial in the odontological area. Eighteen rats had the left lateral incisor extracted and fourteen of them received castor bean alloplastic polymer bone graft in the extraction socket, forming the experimental group. These were divided in two groups with different sacrifice time, 30 and 45 days. The control group that did not receive any treatment. The last animal is the standard gold group that served as example of complete structure. The animals were killed and they had the tissue fragments removed in order to have histological analysis under optical microscopy. It was taken occlusal radiographs and lateral cefalometric radiographs in odontological films profile immediately after the extraction and after the death. The anatomical pieces were removed and processed for making of slices. It was evaluate histologically and radiographically the wound of the extraction sockets with the graft compared to physiologic repair. The result evidenced the maintenance dimension alveolar dental sockets in the groups that received castor bean alloplastic polymer bone graft. The graft technique showed to be efficient, resulting in a minimum decrease of the dimensions of the extraction sockets. In this present work the graft technique with castor bean alloplastic polymer bone graft came effective in the maintenance of the dimensions of the alveolar bone
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Geochemical Modeling of Primary MORB Magmas: Implications for Parental Melting Regimes in Melt Lenses Along-Axis of the Hess Deep RiftDrumm, Stephanie Michelle 23 March 2018 (has links)
The Hess Deep Rift in the East Pacific Rise is a mid-ocean ridge spreading center that produces melts which exhibit geochemical characteristics of evolved MORB. Using basaltic glass samples collected from multiple dive cruises that explored Hess Deep geology, volatile and chemical data were collected at USF using FTIR and EMPA, respectively. In addition, a data suite of samples of glass from Hess Deep were compiled from the EarthChem database. The intention was to use the data suite and models to compare the Hess Deep regime to analog models for mid-ocean ridge crystallization regimes and tectonic structures. The USF and EarthChem samples were then compared to various crystallization models generated in Petrolog3 (Danyushevsky and Plechov, 2011) and COMAGMAT (Ariskin and Barmina, 2004). The starting compositions using depleted, normal, and enriched MORB (Gale et al, 2013) were modeled at depths reflecting an upper and lower melt lens along the rift axis. The volatile components of the USF samples were compared to models for water and carbon dioxide behavior in basalt made using VolatileCalc (Newman and Lowenstern, 2002). Based on the comparison of the samples to the forward modeling in Petrolog3, it appears that the geochemical behavior of major and trace elements most closely resembles that of small amounts of fractional crystallization and re-assimilation of accessory minerals. The VolatileCalc models suggest that the USF samples most likely followed a degassing pathway at depths corresponding to the shallow melt lens. When considering the analog models for ophiolite sequences and melt flow beneath a fast-spreading ridge, it appears that the melt regime at Hess Deep deviates from both standing theories. Instead the most likely mechanisms are shallow crystallization, at depths equal to or less than an upper melt lens, and shallow dynamic degassing.
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Avaliação da manutenção da dimensão de rebordo alveolar após enxerto aloplástico de composto ósseo de rícino pós-extração dental em rato, estudo radiográfico e histológico / Evaluation of ridge preservation after castor bean alloplastic polymer bone graft post-extraction sockets of rats a radiographical and histological studyFernando Silva de Castro 22 February 2006 (has links)
O objetivo deste trabalho é o estudo do comportamento do enxerto de composto ósseo de rícino e sua eficácia na manutenção do rebordo alveolar. Através de avaliações histológicas e radiológicas. A cicatrização após as extrações dentárias faz com que o osso da região entre em um processo de atrofia. Existem técnicas preventivas para manutenção das dimensões do sitio de extração. As técnicas podem ser: implantes dentários, regeneração óssea guiada, enxertos ósseos e estas técnicas combinadas. A técnica de enxerto ósseo se baseia na ocupação do espaço, pelo biomaterial. O composto ósseo de rícino se destaca entre os aloplásticos, pois é de origem vegetal e tem se mostrado eficiente biomaterial na área odontológica. Foram utilizados neste trabalho 19 ratos Wistar. Dezoito ratos tiveram o incisivo lateral esquerdo extraídos e quatorze deles receberam o implante de composto ósseo de rícino, formando o grupo experimental, estes foram divididos em dois períodos de sacrifício, 30 e 45 dias, assim como o grupo de controle que não recebeu nenhum tipo de tratamento. O último animal é o animal padrão ouro que serviu de exemplo de estrutura íntegra. Os animais foram mortos humanitariamente e tiveram os fragmentos teciduais removidos a fim de serem analisados histologicamente sob microscopia óptica. Foram feitas tomadas radiográficas em filme odontológico de perfil e ântero-posterior imediatamente após a extração e imediatamente após a morte. As peças anatômicas foram retiradas e processadas para confecção de lâminas. Foi comparado radiograficamente e histologicamente o reparo do alvéolo preenchido por composto ósseo de rícino de uso odontológico com reparo fisiológico de outro alvéolo de extração dentária preenchido apenas com o coágulo formado nos dois grupos experimentais. O resultado evidenciou a manutenção dimensão alveolar pós-extração dentária nos grupos que receberam o composto ósseo de rícino. A técnica de preenchimento mostrou ser eficiente, tendo como resultado uma diminuição mínima das dimensões do alvéolo pós-extração dentária. Neste presente trabalho a técnica de preenchimento de alvéolo com o enxerto de composto ósseo de rícino se apresentou eficaz na manutenção das dimensões do osso alveolar / The aim of this work is to study the behavior of the castor bean alloplastic polymer bone graft on ridge preservation. The dental extraction cicatrization process is an atrophy process. There are preventive techniques for maintenance of the dimensions of the alveolar ridge. These techniques are: dental implant, guided bone regeneration, bone graft and the combination of these techniques. The technique of bone graft is based on filling the space with the biomaterial. The castor bean alloplastic polymer bone graft surpasses the alloplastic because it is of vegetable origin and shown efficient biomaterial in the odontological area. Eighteen rats had the left lateral incisor extracted and fourteen of them received castor bean alloplastic polymer bone graft in the extraction socket, forming the experimental group. These were divided in two groups with different sacrifice time, 30 and 45 days. The control group that did not receive any treatment. The last animal is the standard gold group that served as example of complete structure. The animals were killed and they had the tissue fragments removed in order to have histological analysis under optical microscopy. It was taken occlusal radiographs and lateral cefalometric radiographs in odontological films profile immediately after the extraction and after the death. The anatomical pieces were removed and processed for making of slices. It was evaluate histologically and radiographically the wound of the extraction sockets with the graft compared to physiologic repair. The result evidenced the maintenance dimension alveolar dental sockets in the groups that received castor bean alloplastic polymer bone graft. The graft technique showed to be efficient, resulting in a minimum decrease of the dimensions of the extraction sockets. In this present work the graft technique with castor bean alloplastic polymer bone graft came effective in the maintenance of the dimensions of the alveolar bone
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On Family and Fences: Tracing Melungeon Roots in the Blue Ridge Mountains of Virginia and TennesseeHorton, Ron 01 May 2010 (has links)
The Melungeons are a group of indeterminable origin living in the Blue Ridge Mountains of Southeastern Tennessee and Southwestern Virginia. This thesis describes characteristics of these tri-racial isolates and gives theories as to their mysterious origins. Being darker skinned, the Melungeons were pushed into more mountainous regions by European colonists in the early 1700’s. While multiple hypotheses exist as to the origin of the Melungeon people, there is no single theory that is accepted by all scholars.
Dr. Brent Kennedy’s The Melungeons: The Resurrection of a Proud People, served as a catalyst for my Melungeon research. Kennedy is my cousin, and his book provided facts behind the family stories I recalled from childhood. It also linked me to other famous Melungeons such as Brandy Jack Mullins and Mahala Mullins. Although there are an abundance of stories and facts about my Melungeon heritage, there is also much history that has been lost.
This thesis traces my Melungeon roots, following the family stories of N.B. Kennedy, Brandy Jack Mullins, Mahala Mullins, and Kenneth Kennedy. In order to fully understand these people and their stories, I not only researched their history, but I also visited the areas where they lived and died. In this manner, I was able to gain a better understanding my own family as well as the history of the Melungeons.
A person’s past is pieced together through oral history, written records, fading pictures, and personal artifacts. Along with these methods, we as writers and researchers add a bit of our own thought and imagination to fill in the gaps of a person’s life. In this manner, personal mythology is created. This thesis ends with an example of one fictionalized story from my family surrounding the death of my uncle, Kenneth Kennedy.
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Evaluating a Sustainable Community Development Initiative Among the Lakota People on the Pine Ridge Indian ReservationMosman, Sarah A. 12 1900 (has links)
This thesis details my applied thesis project and experience in the evaluation of a workforce development through sustainable construction program. It describes the need of my client, Sweet Grass Consulting and their contractual partner, the Thunder Valley Community Development Corporation, in the evaluation of Thunder Valley CDC's Workforce Development through Sustainable Construction Program. My role involved the development of an extensive evaluation package for this program and data analysis of evaluation materials to support Thunder Valley CDC's grant-funded Workforce Development Program. I place the efforts of Thunder Valley CDC in the context of their community, the Pine Ridge Reservation of the Lakota People, and within an historical and contemporary context to highlight the implications of the efforts of Thunder Valley CDC. Using the theoretical frameworks of cultural revitalization and community economic development, I attempt to highlight two important components of Thunder Valley CDC's community development efforts - cultural revitalization for social healing, and development that emphasizes social, community and individual well-being. Thunder Valley CDC's Workforce Development through Sustainable Construction Program is still in its early stages, and so this first year of implementation very much represented a pilot phase. However, while specific successes are difficult to measure at this point, general successes are viewable in the daily operations of Thunder Valley CDC that exemplify their stated mision and goals. These successes include initiatives that holistically address community needs; relevancy in the eyes of the community they serve; support for the community and for Program participants' unique challenges; and a cultural restoration and revitalization emphasis that underlies and strengthens all of this. The program thus has the potential to provide a model for community development by challenging dominant "development" paradigms and utilizing community resources and assets for community development that reflects the community's values and worldviews.
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The evolution and population genetics of hydrothermal vent megafauna from the Scotia SeaRoterman, Christopher Nicolai January 2013 (has links)
This project used a variety of genetic markers to investigate the evolution and population genetics of hydrothermal vent fauna that were recovered from the Scotia Sea, in the Atlantic sector of the Southern Ocean. The origins of one of these species, an undescribed species of Kiwa sp. found on the East Scotia Ridge (ESR) and its constituent family Kiwaidae, a group of vent and seep-associated decapod squat lobsters (infraorder Anomura) was investigated using a concatenated nine-gene dataset and key divergences were dated using fossil calibrations. These results confirm earlier research showing Kiwaidae reside in the superfamily Chirostyloidea, but form a monophyletic clade with the non-chemosynthetic family Chirostylidae and not Eumunididae. Chirostyloid families diverged in the Cretaceous, although extant Kiwaidae radiated in the Eocene, consistent with many other chemosynthetic taxa that appear recently derived. The basal tree position of Pacific species (and the Alaska location of a likely stem-lineage kiwaid fossil) suggests kiwaids originated in the East Pacific. Within a Southern Hemisphere clade, the divergence between the southeastern Pacific K. hirsuta and a non-Pacific lineage (Kiwa sp. ESR and Southwest Indian Ridge kiwaids) is no earlier than 25.9 Ma, consistent with a spread from the Pacific into the Scotia Sea and beyond via now-extinct active ridge connections or mediated by a Miocene onset of the Antarctic Circumpolar Current (ACC) through a newly-opened Drake Passage. This project also investigated the population genetics of three undescribed species found at two vent fields ~ 440 km apart at either end of the ESR: Kiwa sp., a peltospirid gastropod and Lepetodrilus sp. limpets. Lepetodrilus sp. was also found at the Kemp Caldera, a submerged part of the South Sandwich Islands (SSI). Analyses of cytochrome c oxidase subunit 1 (COI) as well as microsatellite loci developed from Roche 454 sequence libraries revealed no differentiation along the ESR for all three species consistent with panmixia, or the dominance of non-equilibrium processes between vent field colonies within a metapopulation, possibly enhanced further by cold-induced arrested larval development. Despite apparent connectivity along the ESR, both COI and microsatellites revealed differentiation between ESR limpets and Kemp Caldera limpets ~ 95 km to the east, possibly owing to the hydrographic isolation of the caldera. Both COI and microsatellite diversity patterns were consistent with recent (< 1 Ma) demographic expansions for all three species (although the influence of selection sweeps on COI cannot be discounted); a pattern observed worldwide at vent communities and may reflect demographic instability over time as a consequence of the stochastic birth and death of vent colonies within a metapopulation. Different COI bottleneck ages between the three species (excluding the influence of possible selection) as well as the absence of kiwaids and peltospirids at Kemp, have been attributed to differences in life history, in particular larval morphology and presumed dispersal strategy. These results highlight the role of larval dispersal of vent fauna along active spreading ridges, both in maintaining vent metapopulations across vent colonies prone to stochastic birth and extinction in the short term, but also in the spread of taxa globally and the formation of biogeographic provinces. The likelihood that the three species presented here exist at vents east of the ESR and SSI, prompts further exploration along ridges in the South Atlantic, in order to investigate the effect of the ACC in enhancing gene flow and delineating biogeographic provinces.
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Experimentelle Untersuchung zur Alveolarkammaugmentation mit Poly-(D,L-)Laktid-Membranen / Experimental investigation of alveolar ridge augmentation using a poly-(d,l-)lactide-membraneGründel, Marcel 11 March 2015 (has links)
No description available.
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Comparação de métodos de estimação para problemas com colinearidade e/ou alta dimensionalidade (p > n ) / Comparison of estimation methods for problems with collinear and/or high dimensionality (p > n)Casagrande, Marcelo Henrique 29 April 2016 (has links)
Este trabalho apresenta um estudo comparativo do poder de predição de quatro métodos de regressão adequados para situações nas quais os dados, dispostos na matriz de planejamento, apresentam sérios problemas de multicolinearidade e/ou de alta dimensionalidade, em que o número de covariáveis é maior do que o número de observações. No presente trabalho, os métodos abordados são: regressão por componentes principais, regressão por mínimos quadrados parciais, regressão ridge e LASSO. O trabalho engloba simulações, em que o poder preditivo de cada uma das técnicas é avaliado para diferentes cenários definidos por número de covariáveis, tamanho de amostra e quantidade e intensidade de coeficientes (efeitos) significativos, destacando as principais diferenças entre os métodos e possibilitando a criação de um guia para que o usuário possa escolher qual metodologia usar com base em algum conhecimento prévio que o mesmo possa ter. Uma aplicação em dados reais (não simulados) também é abordada. / This paper presents a comparative study of the predictive power of four suitable regression methods for situations in which data, arranged in the planning matrix, are very poorly multicolinearity and / or highdimensionality, wherein the number of covariatesis greater the number of observations. In this study, the methods discussed are: principal component regression,partial least squares regression,ridge regression and LASSO. The work includes simulations, where in the predictive power of each of the techniques is evaluated for different scenarios defined by the number of covariates, sample size and quantity and intensity ratios (effects) significant, high lighting the main dffierences between the methods and allowing for the creating a guide for the user to choose which method to use based on some prior knowledge that it may have. An applicationon real data (not simulated) is also addressed.
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