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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.
231

Labor and social barter in an Appalachian community: Carroll County, Virginia, 1880s-1930s

Webb, Keith Robert 21 July 2009 (has links)
From the 1880s to the 1930s Carroll County, Virginia, experienced economic changes which were sweeping many areas of the Appalachian mountains. Industrialization brought Sawmills and iron ore mining activity. Throughout this fifty-year period, Carroll County residents continued to labor at agricultural activity. Laborers began to work in the new industries while continuing to farm. Throughout this period, laborers moved from place to place seeking economic opportunities on farms and in industry. Carroll County residents practiced a diversity of labor to support their families. Carroll County residents also helped each other through the practice of mutual aid. When crops needed harvesting, neighboring farmers pitched in to help. Younger residents took care of and housed their elderly kin. These practices of mutual aid did not cease to exist with the arrival of industrialization. Sometimes, new labor opportunities provided people with new ways to interact with and help family and community. Preston Webb exemplifies the fact of Appalachian migration, mobility, work diversity, and mutual aid. He moved about the Carroll County region for work opportunities. He worked at a variety of agricultural and non-agricultural jobs to support his family. He also housed family members during times of crisis. Other Carroll County residents were at different levels socially and economically, but they too operated from a world of mutual help, work diversity, and mobility. This thesis explores these phenomenon through the stories of these residents of Carroll County. / Master of Arts
232

Investigation of salinity and nutrient characteristics of two groundwater based flow systems on Virginia's Eastern Shore

Nippert, Howard Christian 24 November 2009 (has links)
The freshwater-saltwater transition zone was investigated in an unconfined aquifer on Virginia’s Eastern Shore. The Steelman’s Landing study site consisted of a well transect which began in an 800 meter wide upland agricultural field, and proceeded seaward through a 300 meter wide mesic forest, 300 meter wide saltmarsh, and 550 meters offshore into Magothy Bay. Wells in the surficial, Columbia aquifer were screened over 30 centimeters at depths of 3.05, 9.14, and 15.25 meters below the surface. Most monitoring sites consisted of clusters of multiple wells which were periodically sampled for inorganic nutrients and salinity. In the saltmarsh portion of the study site, salinity of monitoring well samples indicated the presence of two horizontal flow systems. The deeper flow system contained freshwater flowing seaward from upland areas. The shallower system contained saline water recharged by the tides and concentrated by evaporation. Salinity measurements and positive vertical (0.019-0.046 meters/meter) and horizontal (0.001-0.005 m/m) hydraulic gradients of wells located across the marsh suggested movement of freshwater offshore which was confirmed by the direct measurement of submarine groundwater discharge (SGWD) using seepage meters. Upland wells contained high nitrate freshwater (>600μmol / 1 NO₃⁻, <1.0% salinity), while shallow (3.05m) wells located from the marsh-forest interface across the saltmarsh to Magothy Bay contained increasingly saline water and reduced nitrate levels (<1μmol / 1 NO₃⁻, 4-21% salinity). Deeper (9.14m) wells across the study site from the agricultural field seaward 420 meters offshore, contained fresh water (<1.0%). A deep (9.14m) well located 550 meters offshore contained water of nearly equal salinity to ambient water in Magothy Bay (30-32%). This represented a point on the saline side of the transition zone. In order to more completely identify and account for movement of nutrients in groundwater across the study site from upland agricultural fields to Magothy Bay, the second portion of the study consisted of an investigation of nutrient movement through a small tidal creek located adjacent to the Steelman’s Landing study site. Creek water had a higher velocity and shorter residence time in comparison to groundwater. Exercises describing nutrient movement were conducted in February and May, 1993 in Wall’s Landing Creek. A seasonal component of nutrient reduction was investigated as indicated by ambient creek samples, and bulk flux of nutrients across the sediment-water interface using light and dark benthic dome chambers. Nitrate flux measurements for the February and May sampling exercises were approximately 14,500 μmol/sec (17.6kg/day as N) and 5400 μmol/sec (6.5kg/day as N), respectively. The primary mechanism of nitrate reduction on reaching the creek channel was physical dilution by seawater. / Master of Science
233

Subsurface transport of fertilizer-applied nitrogen on the eastern shore of Virginia

Salley, W. Bryan 06 October 2009 (has links)
The movement of nitrogen from the surface, where it is applied as fertilizer, to groundwater is of importance due to the health concerns associated with nitrate and potential eutrophication of groundwater impacted surface water. The computer model, PRZM (Pesticide Root Zone Model) was used to simulate the transportation of nitrogen through the soil column, past the crop root zone to groundwater. Then MOC (Method of Characterization), a groundwater model, was used to transport the nitrogen that had reached the water table offsite. Results were compared to existing field data in an attempt to verify the validity of the simulation. / Master of Science
234

Patrick County, Virginia and the Civil War, 1860-1880

Becker, Gertrude Harrington 03 March 2009 (has links)
In 1860, Patrick County. like the rest of Virginia and much of the South. wavered uneasily on the brink of secession. In a county where large planters were few, secession was not overwhelmingly popular. Slaveholding families, however, constituted almost one quarter of the white population in Patrick, as they did across the South, and when Virginia seceded. Patrick Countians flocked to serve in the Confederate Army. Although situated in Virginia, Patrick managed to escape physical decimation from war. In fact, no battles occurred in the county and Federal troops only invaded the county once in four years. Nevertheless, the Civil War came home to Patrick in a variety of ways: men were killed, livestock and crops impressed, and farms destroyed. With its prosperity of the 1850's disrupted by the war. Patrick's agricultural output dramatically decreased, industry failed, and labor shortages ensued. Despite the changes the Civil War brought to Patrick, the highest echelon of Patrick's social structure changed little. Those white men who had been well off before the war continued to flourish and continued to own the most and most valuable real estate. Small farmers before the war generally remained small farmers. Free blacks did not gain much status over the decades, and freedmen owned scarcely any land nor personal property; neither group by 1880 had achieved literacy. In Patrick County the rich stayed rich and the planters remained the most influential. / Master of Arts
235

An investigation of the effects of temperature and suspended sediment on the Landsat MSS reflectance of John H. Kerr Reservoir

Sharp, Warren Lee January 1983 (has links)
The report herein consisted of two objectives, the first of which was a data collection effort in John H. Kerr Reservoir. Ten field monitoring trips were performed between March 30, 1981 and March 3, 1982. The temperature, velocity, and depth data from those trips are contained in Appendix A. Plots of temperature versus depth at the stations chosen in the reservoir are contained in Appendix B. The second objective was an application of the database to Landsat MSS data available during the same period of record. The effects of temperature and total suspended solids on Landsat MSS reflectance were investigated. The effect of increasing temperature was a notable decrease in reflectance especially in Bands 4 and 5. This temperature effect may have been influenced by other water quality parameters that were not measured. The effect of increasing total suspended solids was a pronounced reflectance increase in Band 5. / M.S.
236

Comparative resource use by two species of black bass in riverine and impounded sections of the New River, Virginia

Scott, Mark C. 24 January 2009 (has links)
Two species of black bass, smallmouth bass Micropterus dolomieu and spotted bass Micropterus punctulatus, are sympatric in both riverine and impounded sections of the New River, Virginia. Resource use (habitat and diet) by the two species was investigated to determine patterns and extent of resource partitioning between them and how those patterns might differ between lotic and lentic environments. Individual fitness indicators (i.e., growth and body condition factor) were also measured to assess performance of populations of the two species in the study areas. Fitness indicators suggested relatively good performance of both species in both river and impoundment, which implied that competitive pressures were not intense. Diet analyses indicated fairly high overlap in prey types consumed. High fitness combined with considerable diet overlap suggested that food availability was adequate, and that segregation in this impounded river system was not on a trophic basis. The two species were found to segregate spatially, with spotted bass predominant in the impoundment and smallmouth more abundant in the river. Spatial segregation was also apparent within both river and impoundment habitat types. / Master of Science
237

A simulation model for triclosan concentrations in the North and Middle Rivers, Virginia /

Songkiatisak, Preeyaporn. January 2009 (has links) (PDF)
Thesis (M.S.)--James Madison University, 2009. / Includes bibliographical references.
238

C, P and water dynamics in Mycorrhiza / C, P und Wasser Dynamik in der Mykorrhiza

Ditschar, Bernd 20 May 2005 (has links)
No description available.
239

Igbo talking signs in antebellum Virginia religion, ancestors, and the aesthetics of freedom /

Malcolm-Woods, Rachel, Matthews, Donald Henry, Dunbar, Burton L. January 2005 (has links)
Thesis (Ph. D.)--Dept. of Art and Art History and Dept. of History. University of Missouri--Kansas City, 2005. / "A dissertation in art history and history." Advisors: Donald Matthews and Burton Dunbar. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed June 26, 2006. Includes bibliographical references (leaves 263-283). Online version of the print edition.
240

Estudo da participação das proteínas Paxilina e Miosina-Va na infectividade do Vírus Linfotrópico de Células T Humanas do Tipo 1 (HTLV-1)

Jesus, Jaqueline Goes January 2014 (has links)
Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2016-02-15T14:17:14Z No. of bitstreams: 1 Jaqueline Goes de Jesus. Estudo...2014.pdf: 4655999 bytes, checksum: 99ee2ef801cc69dd80d0a344e8f01be2 (MD5) / Approved for entry into archive by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2016-02-15T14:18:33Z (GMT) No. of bitstreams: 1 Jaqueline Goes de Jesus. Estudo...2014.pdf: 4655999 bytes, checksum: 99ee2ef801cc69dd80d0a344e8f01be2 (MD5) / Made available in DSpace on 2016-02-15T14:18:33Z (GMT). No. of bitstreams: 1 Jaqueline Goes de Jesus. Estudo...2014.pdf: 4655999 bytes, checksum: 99ee2ef801cc69dd80d0a344e8f01be2 (MD5) Previous issue date: 2014 / Fundação Oswaldo Cruz, Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / As ORFs I e IV do genoma do HTLV-1 codificam, respectivamente, as proteínas p12/p8 (acessória) e Tax (regulatória). p12/p8, de 99 aminoácidos, pode ser clivada em sua extremidade amino terminal gerando a proteína p8. A primeira clivagem proteolítica de p12 remove o sinal de retenção ao RE, enquanto a segunda clivagem, gera o produto de 8kDa, referido como p8. p12 localiza-se no sistema de endomembranes, residindo em RE e aparato de Golgi, enquanto p8 dirige-se para a membrana plasmática, onde é recrutada para a sinapse imunológica, através da ligação com o receptor de células T (TCR), além de participar da sinapse virológica e da formação de conduítes. A proteína Tax, por outro lado, atua como transativador transcricional do HTLV-1, sendo referida também na indução da expressão de diversos genes celulares, aumentando a proliferação e a migração das células infectadas. Na via de transporte de vesículas secretórias, vesículas produzidas como pós-Golgi são transportadas ao longo do citoesqueleto por motores celulares. A Miosina-Va, um motor não convencional, transporta diversos cargos, incluindo vesículas secretórias, vesículas sinápticas e de retículo endoplasmático. Outra proteína relacionada ao citoesqueleto é a Paxilina, que atua como molécula adaptadora nas adesões focais e cuja expressão está aumentada em indivíduos TSP-HAM. Na tentativa de compreender se Tax influencia no aumento da expressão de Paxilina e, paralelamente, se p8 trafega a partir de Golgi em direção à membrana, de maneira dependente de Miosina-Va, células de linhagem foram transfectadas, com o plasmídeo que expressa Tax ou com plasmídeos que expressam variantes da proteína p12 (pMEp12) fusionada a um tag de HA (hemaglutinina de influenza) e que expressam porções da Miosina-Va, incluindo a cauda completa neuronal conjugada com GFP (MyoVa FTNeu-eGFP), que funciona como dominante negativo e compete com a Miosina-Va constitutiva pelos seus ligantes intracelulares. A localização intracelular das proteínas foi realizada por ensaio de imunofluorescência indireta utilizando anticorpos contra a Paxilina ou contra o tag de HA e a cauda medial da Miosina-Va. Técnicas de microscopia confocal e obtenção de imagens foram realizadas utilizando o microscópio Zeiss LSM 780 (Carl Zeiss Optical, Chester, Va.) e o software Adobe Photoshop CC. Surpreendentemente, nas células que expressavam Tax, a expressão de Paxilina, avaliada por imunofluorescência, foi menor, necessitando de novos ensaios para confirmação dos resultados. Em relação à p12/p8, foi observada a sua sub-localização celular como já descrito na literatura, apresentando-se na região perinuclear (RE e aparato de Golgi), e co-localização entre p12/p8 e Miosina-Va, embora apenas quando o dominante negativo MyoVa FTNeu-eGFP foi expresso simultaneamente com as variantes de p12, a localização de p12/p8 mostrou-se alterada, de pontos dispersos por todo o citoplasma e superfície celular para apresentar-se em forma de grumos agregados independentemente da variante de p12 expressa, sugerindo que a Miosina-Va desempenha um importante papel no tráfego de p8 partindo de Golgi até a superfície celular. / HTLV-1 ORFs I and IV encode respectively p12/p8 (accessory protein) and Tax (regulatory protein). The 99 amino acid p12 protein can be proteolytically cleaved at the amino terminus to generate the p8 protein. The first proteolytic cleavage removes the ER retention/retrieval signal at the amino terminus of p12, while the second cleavage generates the p8 protein. The p12 protein localizes to cellular endomembranes, within the ER and Golgi apparatus, while p8 traffics to lipid rafts at the cell surface and is recruited to the immunological synapse upon T-cell receptor (TCR) ligation, virological synapse and conduits. Tax on the other hand acts as viral transactivator and induces expression of many cellular genes, increasing proliferation and migration of infected cells. In secretory vesicle transport, vesicles produced as post-Golgi are moved along the cytoskeleton by motor proteins. The unconventional myosin motor, Myosin-Va, moves several cargoes including secretory vesicles, synaptic vesicles, and the endoplasmic reticulum. Another cytoskeleton associated protein is Paxillin, an adapter on focal adhesions which expression is increased in TSP-HAM patients. To understand if Tax play a role on increased expression of Paxillin and parallel if p8 traffics from Golgi apparatus to cell surface on a myosin-Va dependent manner, lineage cells were transfected with Tax plasmids or pMEp12 plasmids which express variants (p12WT, p12Δ29 and p12G29S) of the fusion protein of HTLV-1 p12 tagged with the influenza hemagglutinin (HA1) tag and with the Myo-Va plasmids including full-tail neuronal-eGFP conjugated (MyoVa FTNeu-eGFP) plasmid which expresses a negative dominant of myosin Va and competes for intracellular ligands with cellular putative myosin. Proteins intracellular localization were analyzed by indirect immunofluorescence assay using antibodies against Paxillin or the HA-tag and the Myo-Va protein. Confocal microscopy and image collection was performed by using a Zeiss LSM 780 microscope (Carl Zeiss Optical, Chester, Va.) with Adobe Photoshop CC software. Surprisingly in Tax-expressing cells Paxillin fluorescence was decreased requiring another assay to confirm this find. It was reported that p12 expression in Jurkat T, as previous described, was shown in perinuclear region which might be RE and Golgi apparatus and that p12/p8 and MyoVa proteins colocalizes in lineage cells, however only when MyoVa FTNeu-eGFP was simultaneously expressed with pMEp12 plasmids, p12/p8 localization showed to be altered from dots dispersed all over cytoplasm and cell surface to form cytoplasmic aggregates independently on variant of p12 expressed, suggesting that myosin Va plays an important role on traffics of p8 from Golgi to cell surface.

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