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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.
341

Development of an inducible promoter system in Leishmania donovani /

Yan, Shao-feng. January 2000 (has links)
Thesis (Ph. D)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 126-137).
342

Phytoremediation   of heavy metal polluted soils in marginalised regions: opportunities,   limitations and sustainable development

Pronoza, Lesya January 2017 (has links)
Soil pollution is one of the problems that obstruct sustainable development in the affected regions, posing a threat to the local environment, ecosystems and human wellbeing. Phytoremediation is one of the techniques used to clean polluted soils. It relies on the ability of some plants to absorb or stabilize certain substances from soil, including organic and inorganic pollutants. Amaranth was chosen as a potential candidate for the proposed phytoremediation project in Chinandega region, Nicaragua, an area that was heavily used for cotton production in the last century, and is now characterised as having high levels of soil pollution, Cd being one of the most common one. The aspects such as opportunities and limitations for the designing of such a project, as well as its contribution to the sustainable development of the region were examined in this thesis. To further support the investigation, the laboratory experiment was performed to study the uptake rate of Cd by amaranth in a greenhouse conditions. The results of the study show that the main opportunities for the design of this project would be the possibility of combining the cleaning of soil with co-benefits such as producing food and energy, as well as additional removal of organic pollutants. The main limitations would be the lack of initial data about the pollution, and possible economic losses due to inability of using amaranth for food. The implementation of this project in real life would mean a support of sustainable development of the Chinandega region on many levels, including social, environmental and economic benefits. The results of the laboratory pot experiment are yet to be included in the study, as the experiment still continues. / <p>2017-10-30</p>
343

Phytoremediation of heavy metal polluted soils in marginalised regions: opportunities, limitations and sustainable development

Pronoza, Lesya January 2017 (has links)
Soil pollution is one of the problems that obstruct sustainable development in the affected regions, posing a threat to the local environment, ecosystems and human wellbeing. Phytoremediation is one of the techniques used to clean polluted soils. It relies on the ability of some plants to absorb or stabilize certain substances from soil, including organic and inorganic pollutants. Amaranth was chosen as a potential candidate for the proposed phytoremediation project in Chinandega region, Nicaragua, an area that was heavily used for cotton production in the last century, and is now characterised as having high levels of soil pollution, Cd being one of the most common one. The aspects such as opportunities and limitations for the designing of such a project, as well as its contribution to the sustainable development of the region were examined in this thesis. To further support the investigation, the laboratory experiment was performed to study the uptake rate of Cd by amaranth in a greenhouse conditions. The results of the study show that the main opportunities for the design of this project would be the possibility of combining the cleaning of soil with co-benefits such as producing food and energy, as well as additional removal of organic pollutants. The main limitations would be the lack of initial data about the pollution, and possible economic losses due to inability of using amaranth for food. The implementation of this project in real life would mean a support of sustainable development of the Chinandega region on many levels, including social, environmental and economic benefits. The results of the laboratory pot experiment are yet to be included in the study, as the experiment still continues. / <p>20171030</p>
344

How the regional water cycle responds to recent climate change in northwest aridzone of China ?

Huang, Junyi 14 December 2017 (has links)
Climate change has posed significant challenges for the world's sustainable development, and the water cycle is highly dependent on the climate system. In particular, the arid zone fragile ecosystems in northwest China are highly vulnerable to the sophisticated hydrological variations. While ground-based measurements are less capable for large scale hydrological modelling, remote sensing techniques offer enhanced and effective alternatives for various hydrological states/fluxes. With the advancement of the Gravity Recovery and Climate Experiment (GRACE) satellites, the Terrestrial Water Storage (TWS), an integrative measurement of regional hydro-climatic environment, can now be measured as well for examining the overall hydrological response to recent climate change. TWS is an essential element of the water cycle and a key state variable for land surface-atmosphere interaction. Investigating the TWS change is important for understanding the response of the water cycle to climate change. In this study, the intra-annual and inter-annual spatio-temporal change pattern of TWS in Xinjiang Uyghur Autonomous Region of China during 2003-2015 are characterized from Gravity Recovery and Climate Experiment (GRACE) Tellus data products. Sub-regional re-analysis reveals that the increasing/decreasing rate in sub-regions, namely, Altay Mountains (ATM), Junggar Basin (JGB), Tianshan Mountains (TSM), Tarim Basin (TRB) and Kunlun Mountains (KLM), are - 3.41mm, -5.82mm, -6.76mm, -2.59mm and +3.05mm per year in unit of equivalent water height (EWH), respectively. The results suggest that TWS variation presents certain spatio-temporal patterns with spatial heterogeneity. The uncertainties from different GRACE products are also assessed. In conjunction with gridded meteorological data products and land surface model simulations of hydrological variables, the heterogeneous mechanisms of seasonal TWS change are analyzed. The correlation relationship among various hydrologic states/fluxes variables (e.g. snow water, soil water, snow amount) and climatic variables (e.g. temperature and precipitation) with GRACE-derived TWS variation in different sub-regions are investigated. The findings appear to indicate that 1) temperature month-over-month change and temperature anomaly with 4- month time lag, rather than precipitation, are more capable to explain the intra- annual TWS variation; 2) In most part of the study area, the TWS intra-annual change can be primarily attributed to the snow accumulation in winter and melt in spring. On the other hand, the glacier mass variation, which is particularly sensitive to recent climate change, could be a substantial contributor to inter-annual TWS change. The elevation trends over glaciers are estimated based on ICESat altimetry measurements. Correlation analysis results suggest that, during 2003- 2009, the inter-annual TWS loss in Tianshan Mountains (TSM) was tightly associated with glacier mass variation induced by temperature change, particularly in summer. In contrast, TWS gain in Kunlun Mountains (KLM) can be attributed to glacier mass increase. By utilizing remote sensing observation techniques/products, this study has characterized the spatio-temporal change pattern of TWS in northwest arid zone of China, as well as the underlying mechanism. It suggests that TWS is an effective indicator of regional climate change. This study contributes to a better understanding of the hydrologic and climatic processes in arid zone water cycle, and could be beneficial for regional water resources management and climate change adaptation effort.
345

Avaliação do gradiente de contaminação por elementos metálicos e hidrocarbonetos nos sedimentos desde a zona costeira do sistema estuarino de Santos e São Vicente até o Parque Estadual Marinho da Laje de Santos / Evaluation of metals and hydrocarbons gradiente on the sediments from Santos and São Vicente estuary system to Marine State Park of Laje de Santos

GOBBATO, GUSTAVO M. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:05Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:06Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
346

Avaliação do gradiente de contaminação por elementos metálicos e hidrocarbonetos nos sedimentos desde a zona costeira do sistema estuarino de Santos e São Vicente até o Parque Estadual Marinho da Laje de Santos / Evaluation of metals and hydrocarbons gradiente on the sediments from Santos and São Vicente estuary system to Marine State Park of Laje de Santos

GOBBATO, GUSTAVO M. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:05Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:06Z (GMT). No. of bitstreams: 0 / O Parque Estadual Marinho da Laje de Santos (PEMLS) é considerado um dos melhores pontos de mergulho do Brasil além de apresentar grande importância ecológica para a região. Está localizado a 40 km de uma das áreas costeiras mais contaminada do Brasil, o Sistema Estuarino de Santos e São Vicente (SESSV) que apresenta como principais fontes de contaminação as atividades industriais e o maior porto da América Latina. O presente estudo teve como objetivo avaliar o gradiente de contaminação por metais e hidrocarbonetos alifáticos (AH) e policíclicos aromáticos (HPA) nos sedimentos desde o SESSV até o PEMLS para identificar o grau de contaminação e as possíveis fontes dos contaminantes. Amostras de sedimento superficial foram coletadas em pontos distribuídos por todo SESSV, na baia de Santos, na zona marinha adjacente e no PEMLS. Os resultados foram comparados aos valores da qualidade dos sedimentos (VGQS) propostos na literatura para avaliar o grau de contaminação nos sedimentos. De acordo com os resultados, a contaminação por metais e hidrocarbonetos nos sedimentos do SESSV é elevada, acima dos limites estabelecidos nos VGQS, principalmente na porção interna do estuário próximo as atividades industriais. As principais fontes de emissão de contaminantes para o SESSV são os efluentes industriais e a queima de combustíveis fósseis. A zona marinha adjacente, onde está localizada a área de descarte do material dragado, apresentou, depois do estuário, as maiores concentrações de metais e hidrocarbonetos. Essas concentrações foram mais elevadas que as encontradas na baia de Santos. No PEMLS foram registrados indícios de contaminação por Cr, Hg, Ni, Pb e Zn, os quais tem origem de fontes localizadas na costa, que exportam os contaminantes até a região do PEMLS através das correntes marinhas e ainda fontes locais como barcos de operadoras de mergulho e o tráfego de navios. O Ni apresentou concentrações que estiveram acima dos limites do VGQS. Os hidrocarbonetos não apresentaram concentrações elevadas nos sedimentos do PEMLS. Sendo assim, é importante que seja realizado um controle de poluição no SESSV a fim de remediar as áreas mais contaminadas e um monitoramento continuo do gradiente de contaminação desde a zona de costa até o PEMLS para garantir a preservação desse ecossistema que já apresenta indícios de contaminação. A criação de um plano de manejo específico para o PEMLS auxiliaria na proteção dessa Unidade de Conservação. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
347

Analise de problemas de anisotropia 3D com sub regiões utilizando o metodo dos elementos de contorno / 3D anisotropic problems analysis with sub regions using the boundary element method

Cravo, Anderson Gabriel Santiago 12 August 2018 (has links)
Orientador: Paulo Sollero / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-12T03:46:01Z (GMT). No. of bitstreams: 1 Cravo_AndersonGabrielSantiago_M.pdf: 2052441 bytes, checksum: e71a44434bbb505400bc9105fb3436f5 (MD5) Previous issue date: 2008 / Resumo: Este trabalho apresenta uma ferramenta para análise de sub-domínios utilizando o Método dos Elementos de Contorno 3D (MEC3D). Para a implementação são considerados elementos retangulares, quadráticos e contínuos, isto é, os nós compartilham graus de liberdade e assim, há a necessidade de uma formulação adequada para o tratamento de quinas entre as sub-regiões. As matrizes [H] e [G] são calculadas independentemente do programa de sub-regiões. Isto permite um tratamento computacional eficiente, tendo em vista que atualmente os microcomputadores contam com mais de um processador, viabilizando a computação paralela. Também é apresentada a implementação e o estudo da solução fundamental para anisotropia plena utilizando a Transformada de Radon. Esta formulação é especialmente atraente devido a sua simplicidade de programação, entretanto, ela apresenta uma integral numérica no núcleo do problema o que compromete sua aplicação em problemas de grande porte. Assim, são propostas estratégias para a melhoria do desempenho computacional, como um esquema de interpolação para obtenção das funções de deslocamento e forças de superfície. / Abstract: This work presents a tool for sub-domains analysis using the 3D Boundary Element Method (BEM3D). For its implementation are considered rectangular, quadratic and continuous elements, which means that the nodes share degrees of freedom and so, a proper formulation to deal with corners and edges between the sub regions is required. The matrices [H] and [G] are computed independent of the sub regions program. This makes possible an efficient computational treatment, since the actual computers have more than on processor, and parallel computing is used. Also presents the implementation and the study of the fundamental solution for anisotropic elasticity using the Radon Transform. This formulation is especially attractive due to its simplicity for computational implementations, but it requires a numerical integration in the kernel and then, some strategies are proposed to improve the computational performance. / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica
348

Regional identity: a key to overcome structural weaknesses in peripheral rural regions?

Sedlacek, Sabine, Kurka, Bernhard, Maier, Gunther 10 December 2009 (has links) (PDF)
Depopulation is a well-known phenomenon in peripheral rural regions. The most identified problems are based on structural weaknesses in terms of decreasing business activities and a lack of public infrastructure. In such regions population is mainly older causing major changes in social infrastructure. For instance many schools and kindergartens close down for lack of demand, which hinders young families to migrate to such regions. The result is typically a negative cumulative process of loss of population, loss of jobs, loss of infrastructure, further outmigration. It is an enormous challenge for such regions to overcome this vicious circle. Regional identity can be seen as an important factor to overcome such structural weaknesses. The paper will discuss the concept of regional identity in order to define the term and how it is embedded in regional development theory. The empirical analysis is presenting results focusing on regional identity coming out of a qualitative data analysis and a postal survey. We designed a regional identity index, which measures the intensity of personal and social relationships of both in-migrants and out-migrants.
349

The alliances of a regional power : the case of Syria, 1970-1989

Belcastro, Francesco January 2015 (has links)
The topic of this dissertation is the alliances of a regional power. The framework used to explain this central aspect of International Relations is the realist one, and particularly the work of the Classical Realist Arnold Wolfers. The regional, state and domestic dimension are integrated in order to provide an “updated realist” interpretation of alliances, why states form them, maintain them or break them. This dissertation seeks to recover the concept of state's goals that was central to Classical Realism and then “abandoned” when Neorealism became the dominant Realist paradigm. The case studies used in this research is Syria during the 1970-1989 phase and particularly five pivotal relations: the Egypt 1973 war alliance, the 1978 failed détente with Iraq, the 1979 Damascus-Tehran alliance, the regional client-superpower alliance with the USSR and finally the relation with the Kingdom of Saudi Arabia. By analysing Syria's foreign policy and particularly these five relations this dissertation show how a framework based on realism provides a coherent and insightful interpretation of a regional power's foreign policy.
350

Lichfield and the lands of St Chad

Sargent, Andrew William Steward January 2012 (has links)
This thesis seeks to construct a history for the diocese of Lichfield during the early medieval period. The region is comparatively lacking in evidence, textual or archaeological, when compared to regions further east and south, and so provides a useful case study on which to test the applicability of narratives developed elsewhere. This study analyses what evidence there is from the region, textual (ninth-century episcopal lists, the Lichfield Chronicle, saints’ Lives), archaeological (ecclesiastical settlements, including Lichfield cathedral, and rural settlement) and topographical (distributions of settlement types, field systems and soils), and asks whether it can be interpreted with reference to two specific narratives: first, the ‘minster narrative’, in which a framework of minsters, established during the seventh and eighth centuries, provided pastoral care to the local population; and a territorial narrative based upon the ‘cultural province’, whereby a region defined topographically, usually along watersheds, persistently affected human activity within it, focussing it inwards. The study finds neither narrative entirely satisfactory: early minsters were clustered in the southern and eastern parts of the diocese, suggesting that episcopal agency was more important in ministering to the population than royal or noble minsters, which were founded for other reasons; and several different scales of territory are found to have been influential on the lives of those living in the region. A contextual interpretation is proposed, whereby nodes of habitual practice are identified throughout the landscape, by which people created and negotiated their identities at several different scales; a concept of ecclesiastical lordship is also recommended, by which the diocesan bishop’s relationships with other minsters in the diocese might be more fruitfully understood.

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