928 resultados para Profiles across Mediterranean Sedimentary Systems
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A novel and timely ground penetrating radar (GPR) survey has been carried out in Pantanal from Mato Grosso State, west-central Brazil. Fieldwork was carried out on February/2001 and August/2002 in an attempt to understand avulsion processes that are occurring within Taquari alluvial megafan. The main objectives were to map channel, crevasse and floodplain morphology, as well as active sedimentary bedforms. Many GPR profiles were acquired in the medium and lower Taquari River course. Subaqueous megaripples and exposed sand bars were identified in the medium fan area. Similar features were observed in the lower fan channels, where there were many crevasses in the marginal levees. During the flooding seasons, the flow splays out on to the floodplain, where new distributary channels are being formed. GPR data show that the lower fan, Taquari channel is topographically higher than the adjacent floodplain, thus favoring avulsion as a natural process of river course shifting. GPR data obtained during the wet and dry seasons, together with sedimentology information have been very important in characterizing the fluvial dynamics, and avulsion phenomena. © 2005 Springer Science+Business Media, Inc.
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Here a multiobjective performance index for distribution systems with distributed generation based on a steady-state analysis of the network is proposed. This index quantifies the distributed generation impact on total losses, voltage profile and short circuit currents, and will be used as objective function in an evolutionary algorithm aimed at searching the best points for connecting distributed generators. Moreover, a loss allocation technique, based on the Zbus method, is applied on the original configuration of the network to obtain a good quality initial population. An IEEE medium voltage distribution network is analysed and results are presented and discussed.
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The main objective involved with this paper consists of presenting the results obtained from the application of artificial neural networks and statistical tools in the automatic identification and classification process of faults in electric power distribution systems. The developed techniques to treat the proposed problem have used, in an integrated way, several approaches that can contribute to the successful detection process of faults, aiming that it is carried out in a reliable and safe way. The compilations of the results obtained from practical experiments accomplished in a pilot distribution feeder have demonstrated that the developed techniques provide accurate results, identifying and classifying efficiently the several occurrences of faults observed in the feeder. © 2006 IEEE.
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Includes Bibliography
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Background: The World Health Organization (WHO) study entitled Suicide Trends in At-Risk Territories (START) is an international multisite initiative that aims to stimulate suicide research and prevention across different areas of the globe. A central component of the study is the development of registration systems for fatal and nonfatal suicidal behaviors. Aims: This paper provides an overview of the data collected on suicidal behaviors from the participating locations in the START study. Method: Descriptive statistics on the data are presented in terms of age, sex, and method. Results: Agreater proportion of suicide deaths occurred among males. In all areas except the Philippines more females than males engaged in nonfatal suicidal behaviors. Compared to Australia, Italy, New Zealand, the Philippines, and Hong Kong SAR, in the Pacific Islands suicide most often occurs in younger age groups. Results indicate notable variations between countries in choice of method. A greater proportion of suicides occurred by hanging in Pacific Islands, while inhalation of carbon monoxide, use of firearms, ingestion of chemicals and poisons, and drug overdose were the most frequent methods of choice in other areas. Conclusion: The information drawn from this study demonstrates the enormous variation in suicidal behavior across the areas involved in the START Study. Further research is needed to assess the reliability of the established data-recording systems for suicidal behaviors. The baseline data established in START may allow the development of suicide prevention initiatives sensitive to variation in the profile of suicide across different locations. © 2013 Hogrefe Publishing.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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In soil surveys, several sampling systems can be used to define the most representative sites for sample collection and description of soil profiles. In recent years, the conditioned Latin hypercube sampling system has gained prominence for soil surveys. In Brazil, most of the soil maps are at small scales and in paper format, which hinders their refinement. The objectives of this work include: (i) to compare two sampling systems by conditioned Latin hypercube to map soil classes and soil properties; (II) to retrieve information from a detailed scale soil map of a pilot watershed for its refinement, comparing two data mining tools, and validation of the new soil map; and (III) to create and validate a soil map of a much larger and similar area from the extrapolation of information extracted from the existing soil map. Two sampling systems were created by conditioned Latin hypercube and by the cost-constrained conditioned Latin hypercube. At each prospection place, soil classification and measurement of the A horizon thickness were performed. Maps were generated and validated for each sampling system, comparing the efficiency of these methods. The conditioned Latin hypercube captured greater variability of soils and properties than the cost-constrained conditioned Latin hypercube, despite the former provided greater difficulty in field work. The conditioned Latin hypercube can capture greater soil variability and the cost-constrained conditioned Latin hypercube presents great potential for use in soil surveys, especially in areas of difficult access. From an existing detailed scale soil map of a pilot watershed, topographical information for each soil class was extracted from a Digital Elevation Model and its derivatives, by two data mining tools. Maps were generated using each tool. The more accurate of these tools was used for extrapolation of soil information for a much larger and similar area and the generated map was validated. It was possible to retrieve the existing soil map information and apply it on a larger area containing similar soil forming factors, at much low financial cost. The KnowledgeMiner tool for data mining, and ArcSIE, used to create the soil map, presented better results and enabled the use of existing soil map to extract soil information and its application in similar larger areas at reduced costs, which is especially important in development countries with limited financial resources for such activities, such as Brazil.
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Mapas geológicos e cartas estratigráficas das bacias sedimentares do Amazonas e do Solimões foram revisados, ¬enfatizando-se as formações Alter do Chão, Içá e Solimões, detentoras das maiores reservas de água doce subterrânea, nessas bacias. A carência de informações sobre essas formações foi minimizada pela utilização de amostras de sondagens estratigráficas e de perfis construtivos, litológicos e geofísicos de poços de captação de água e de petróleo obtidos na Base Operacional Geólogo Pedro de Moura, região de Urucu, cerca de 650 km a sudoeste de Manaus (AM). Na Bacia do Amazonas, o Sistema Aquífero Alter do Chão comporta aquíferos livres e confinados, com coeficiente de transmissividades entre 1,5 x 10-3 e 9,1 x 10-3 m2/s, indicados para abastecimento público; na Bacia do Solimões, esse Sistema é confinado pelo Aquiclude Solimões, ao qual se sobrepõe o Sistema Aquífero Içá-Solimões. A reserva de água estimada é de 33.000 km3. O Sistema Aquífero Içá-Solimões, em Urucu, é livre-confinado, com dois aquíferos hidraulicamente conectados: o mais superficial, com topo e base em profundidades próximas de 20 e 70 m, respectivamente, e o mais profundo, entre 50 e 120 m. Com área de afloramento na Bacia do Solimões de 948.600 km2, a reserva estimada desse sistema foi calculada em 7.200 km3, menos expressiva que a do Sistema Aquífero Alter do Chão. Os parâmetros hidrodinâmicos médios foram: T = 3 x 10-3 m2/s, S = 5 x 10-4 e K = 1 x 10-4m/s, de ordens de grandeza similares aos valores encontrados no Sistema Aquífero Alter do Chão. Avaliando-se as inter-relações regionais e potencialidades desses dois sistemas aquíferos procurou-se contribuir para o conhecimento hidrogeológico na Região Hidrográfica Amazônica, onde as pesquisas sobre águas subterrâneas ainda são incipientes.
Influence of abutment-to-fixture design on reliability and failure mode of all-ceramic crown systems
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Accurate paleoenvironmental reconstruction relies on the correct interpretation of the postmortem history of skeletal remains in shelly assemblages. In contrast to marine settings, actualistic taphonomic studies are lacking for shell-rich concentrations in freshwater riverine systems. In particular, the taphonomic pathways and the origins of taphonomic signatures that are recorded in bioclasts from fluvial settings are poorly known. In this study, we addressed this issue by comparing the taphonomic signatures and shell-damage profiles among shells of freshwater mollusks recorded both in death and in fossil assemblages from the same fluvial environment. Our data indicated that dissolution was the most pervasive taphonomic process leading to the destruction of the shells. The loss of taphonomic information extended beyond shell dissolution in the riverbed, or the early diagenesis in the sedimentary record. The loss of biological information from the living community through the death assemblage, until the incorporation of shells as fossils, mainly occurred during the time the shells were in the sediment-water interface. Though this destruction affected primarily dead shells, reworked fossils also became vulnerable because they were carried out into the river load again by channel avulsion. A model that included the main taphonomic pathways followed by the molluscan shells in the fluvial Touro Passo Formation (Pleistocene-Holocene) is discussed. In this model, two main destructive domains were recognized, which were the biological, physical, and chemical processes operating at the taphonomically active zone (= TAZ domain) and the pedogenetic domain.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The Areado Group of the Sanfranciscana Basin is a Lower Cretaceous continental sedimentary system that is correlated to the Brazilian Pre-Salt beds. The Aerado Group is composed of Abaeté, Quiricó and Três Barras formations. Paleocurrent data for the Areado Group were previously presented, although not systematically which prevented significative interpretations on the basin paleogeography. This work attempts to systematically evaluate paleocurrent data, aiming to recognize depositional environment and paleogeographic reconstruction, based on the sedimentary facies and paleocurrents measurements along vertical profiles. Fluvial paleocurrents of the Abaeté Formation indicate paleoflows towards NW whereas aeolian palecurrents of the Três Barras Formation show paleowinds towards SW. The depositional systems interpreted for the Areado Group were: braided river, alluvial fan, lacustrine, playa lake, fluvial-deltaic and aeolian. The combined analyses of facies and paleocurrents allowed a reliable paleogeographic reconstruction of the basin, with paleodip towards northwest, paleowinds towards south-southwest and source-area located at southeast. These results indicate that paleowinds were orthogonal to paleostream, but parallel to depositional strike of the basin. The interpreted depositional systems characterize a desert environment during the Abaeté sub-basin times. The association of dunes and wet interdunes followed by large scale dunes and dry interdunes suggests a decrease in humidity towards the top of the Três Barras Formation, with a dry aeolian system onlapping the basement. The observed decrease of humidity in Sanfranciscana Basin may reflect local or regional paleoclimatic changes during the opening of the South Atlantic, but this assumption is only tentative
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In recent decades the management of large game mammals has become increasingly intensive in south central Spain (SCS), resulting in complex epidemiological scenarios for disease maintenance, and has probably impeded schemes to eradicate tuberculosis (TB) in domestic livestock. We conducted an analysis of risk factors which investigated associations between the pattern of tuberculosis-like lesions (TBL) in wild boar (Sus scrofa) and red deer (Cervus elaphus) across 19 hunting estates from SCS and an extensive set of variables related to game management, land use and habitat structure. The aggregation of wild boar at artificial watering sites was significantly associated with an increasing risk of detecting TBL in both species, which probably relates to enhanced opportunities for transmission. Aggregation of wild boar at feeding sites was also associated with increased risks of TBL in red deer. Hardwood Quercus spp. forest availability was marginally associated with an increased risk of TB in both species, whereas scrubland cover was associated with a reduced individual risk of TBL in the wild boar. It is concluded that management practices that encourage the aggregation of hosts, and some characteristics of Mediterranean habitats could increase the frequency and probability of both direct and indirect transmission of TB. These findings are of concern for both veterinary and public health authorities, and reveal tuberculosis itself as a potential limiting factor for the development and sustainability of such intensive game management systems in Spanish Mediterranean habitats.