38 resultados para Climate Leaf Analysis Multivariate Program (CLAMP)


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Dissertação para obtenção do Grau de Doutor em Ambiente

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This paper describes the palaeoweathering, cementation, clay minerals association and other closely related characteristics of central Portugal allostratigraphic Tertiary units (SLD's), that can be used for palaeoclimatic interpretation and palaeoenvironmental reconstruction. Lateral and vertical changes in palaeosols are of value for improving our understanding of the autocyclic and allocyclic controls on sediment acumulation in an alluvial basin, but they can also have stratigraphic importance. In some cases it is concluded that the geomorphological setting may have been more decisive than climatic conditions to the production of the palaeoweathering. During late Palaeogene (SLD7-8), surface and near-surface silicification were developed on tectonically stable land surfaces of minimal local relief under a semi-arid climate; groundwater flow was responsible for some eodiagenesis calcareous accumulations, with the neoformation of palygorskite. Conditions during the Miocene (SLD9-11) were favourable for the smectization of the metamorphic basement and arenization of granites. Intense rubefaction associated with basement conversion into clay (illite and kaolinite), is ascribed to internal drainage during late Messinian-Zanclean (SLD12). During Piacenzian (SLD13) intense kaolinization and hydromorphism are typical, reflecting a more humid and hot temperate climate and important Atlantic fluvial drainage. Later on (Gelasian-early Pleistocene ?; SLD14). more cold and dry conditicns are interpreted, at the beginning of the fluvial incision sage. Silica cementation is identified in the upper Eocence-Oligocene ? (SLD18; the major period of silicification), middle to upper Miocene (SLD10)and upper Tortonian-Messinian (SLD11); these occurrences are compatible with either arid or semi-arid conditions and the establishment of a flat landscape upon which a silcrete was developed.

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Dissertação para obtenção do Grau de Mestre em Engenharia e Gestão Industrial

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Dissertação para obtenção do Grau de Doutor em Engenharia do Ambiente

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Tese de doutoramento em Ciências da Educação

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Desertification is a critical issue for Mediterranean drylands. Climate change is expected to aggravate its extension and severity by reinforcing the biophysical driving forces behind desertification processes: hydrology, vegetation cover and soil erosion. The main objective of this thesis is to assess the vulnerability of Mediterranean watersheds to climate change, by estimating impacts on desertification drivers and the watershedsâ resilience to them. To achieve this objective, a modeling framework capable of analyzing the processes linking climate and the main drivers is developed. The framework couples different models adapted to different spatial and temporal scales. A new model for the event scale is developed, the MEFIDIS model, with a focus on the particular processes governing Mediterranean watersheds. Model results are compared with desertification thresholds to estimate resilience. This methodology is applied to two contrasting study areas: the Guadiana and the Tejo, which currently present a semi-arid and humid climate. The main conclusions taken from this work can be summarized as follows: ⢠hydrological processes show a high sensitivity to climate change, leading to a significant decrease in runoff and an increase in temporal variability; ⢠vegetation processes appear to be less sensitive, with negative impacts for agricultural species and forests, and positive impacts for Mediterranean species; ⢠changes to soil erosion processes appear to depend on the balance between changes to surface runoff and vegetation cover, itself governed by relationship between changes to temperature and rainfall; ⢠as the magnitude of changes to climate increases, desertification thresholds are surpassed in a sequential way, starting with the watershedsâ ability to sustain current water demands and followed by the vegetation support capacity; ⢠the most important thresholds appear to be a temperature increase of +3.5 to +4.5 ºC and a rainfall decrease of -10 to -20 %; ⢠rainfall changes beyond this threshold could lead to severe water stress occurring even if current water uses are moderated, with droughts occurring in 1 out of 4 years; ⢠temperature changes beyond this threshold could lead to a decrease in agricultural yield accompanied by an increase in soil erosion for croplands; ⢠combined changes of temperature and rainfall beyond the thresholds could shift both systems towards a more arid state, leading to severe water stresses and significant changes to the support capacity for current agriculture and natural vegetation in both study areas.

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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia do Ambiente

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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau em Mestre em Engenharia Física

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X-Ray Spectrom. 2003; 32: 396â401

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Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Ciência e Sistemas de Informação Geográfica

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RESUMO - Enquadramento/objectivos: Apesar do elevado nível de comprometimento em estratégias eficazes para o controlo da tuberculose, em todo o mundo, esta constitui ainda um sério problema de Saúde Pública, com uma estimativa global de 9,4milhões de casos novos em 2008 e 1,8milhões de mortes/ano. O reduzido conhecimento das barreiras e facilitadores para o sucesso terapêutico constitui um importante obstáculo na procura de soluções eficazes de melhoramento da qualidade dos programas de controlo da tuberculose. Este estudo procura contribuir para a identificação atempada de doentes com perfis preditivos de insucesso terapêutico, através da identificação inicial de potenciais determinantes do resultado, com base num modelo epidemiológico e estatístico. Métodos: Foi desenvolvido um estudo de caso-controlo para a população de casos notificados ao Programa Nacional de Controlo da Tuberculose (n=24491), entre 2000-2007. Os factores preditivos de insucesso terapêutico foram identificados na análise bivariada e multivariada, com um nível de significância de 5%; a regressão logística foi utilizada para estimar a odds ratio de insucesso terapêutico, em comparação com o sucesso terapêutico, para diversos factores identificados na literatura, e para os quais os dados se encontravam disponíveis. Resultados: A dependência alcoólica (OR=2,889), o país de origem (OR=3,910), a situação sem-abrigo (OR=3.919), a co-infecção pelo VIH (OR=5,173), a interrupção (OR=60.615) ou falha terapêutica no tratamento anterior (OR=67.345) e a duração do tratamento inferior a 165 dias (OR=1930,133) foram identificados como factores preditivos de insucesso terapêutico. A duração do tratamento inferior a 165 dias provou ser o mais importante determinante do resultado terapêutico. Conclusões: Os resultados sugerem que um doente imigrante, em situação de sem-abrigo, dependente alcoólico, com tratamentos anteriores para a tuberculose e co-infectado pelo VIH apresenta uma elevada probabilidade de insucesso terapêutico. Assim, deverão ser definidas estratégias específicas, centradas no doente por forma a impedir este resultado. A base de dados (SVIG-TB), provou ser uma ferramenta de qualidade para a investigação sobre diversos aspectos do controlo da tuberculose. ------------------------------- ABSTRACT - Background/Objective: Despite the high commitment in good strategies for tuberculosis control worldwide, this is still a serious Public Health problem, with global estimates of 9,4million new cases in 2008 and 1,8million deaths/year. The poor understanding of the barriers and facilitators to treatment success is a major obstacle to find effective solutions to improve the quality of tuberculosis programs. This study tries to contribute to the timely identification of patients with predictive profiles of unsuccessful treatment outcomes, through the initial identification of characteristics probably affecting treatment outcome, found on the basis of an epidemiological and statistical model. Methods: A case-control study was conducted for the population of cases notified to the National Program for Tuberculosis Control (n=24 491), between 2000-2007. Predictive factors for unsuccessful outcome were assessed in a bivariate and multivariate analysis, using a significance level of 5%; a logistic regression was used to estimate the odds-ratio of unsuccessful, as compared to successful outcome, for several factors identified in the literature and to which data was available. Results: Alcohol abuse (OR=2,889), patient´s foreign origin (OR=3,910), homelessness (OR=3,919), HIV co-infection (OR=5,173), interruption (OR=60,615) or unsuccessful outcome in the previous treatment (OR=67,345) and treatment duration below 165 days (OR=1930,133) were identified as predictive of unsuccessful outcomes. A low treatment duration proved to be the most powerful factor affecting treatment outcome. Conclusions: Results suggest that a foreign-born patient, alcohol abuser, who has had a previous treatment for tuberculosis and is co-infected with HIV is very likely to have an unsuccessful outcome. Therefore, specific, patient-centered strategies should be taken to prevent an unsuccessful outcome. The database (SVIG-TB), has proved to be a quality tool on research of various aspects of tuberculosis control.

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Dissertation to obtain the degree of Doctor in Electrical and Computer Engineering, specialization of Collaborative Networks

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Dissertação para obtenção do Grau de Mestre em Lógica Computacional

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Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Estatística e Gestão de Informação

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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.