1000 resultados para 7140-201


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This study investigates the landscape evolution and soil development in the loess area near Regensburg between approximately 6000-2000 yr BP (radiocarbon years), Eastern Bavaria. The focus is on the question how man and climate influenced landscape evolution and what their relative significance was. The theoretical background concerning the factors that controlled prehistoric soil erosion in Middle Europe is summarized with respect to rainfall intensity and distribution, pedogenesis, Pleistocene relief, and prehistoric farming. Colluvial deposits , flood loams, and soils were studied at ten different and representative sites that served as archives of their respective palaeoenvironments. Geomorphological, sedimentological, and pedological methods were applied. According to the findings presented here, there was a high asynchronity of landscape evolution in the investigation area, which was due to prehistoric land-use patterns. Prehistoric land use and settlement caused highly difIerenciated phases of morphodynamic activity and stability in time and space. These are documented at the single catenas ofeach site. In general, Pleistocene relief was substantially lowered. At the same time smaller landforms such as dells and minor asymmetric valleys filled up and strongly transformed. However, there were short phases at many sites, forming short lived linear erosion features ('Runsen'), resulting from exceptional rainfalls. These forms are results of single events without showing regional trends. Generally, the onset of the sedimentation of colluvial deposits took place much earlier (usually 3500 yr BP (radiocarbon) and younger) than the formation of flood loams. Thus, the deposition of flood loams in the Kleine Laaber river valley started mainly as a consequence of iron age farming only at around 2500 yr BP (radiocarbon). A cascade system explains the different ages of colluvial deposits and flood loams: as a result of prehistoric land use, dells and other minor Pleistocene landforms were filled with colluvial sediments. After the filling of these primary sediment traps , eroded material was transported into flood plains, thus forming flood loams. But at the moment we cannot quantify the extent ofprehistoric soil erosion in the investigation area. The three factors that controlled the prehistoric Iandscapc evolution in the Ioess area near Regensburg are as follows: 1. The transformation from a natural to a prehistoric cultural landscape was the most important factor: A landscape with stable relief was changed into a highly morphodynamic one with soil erosion as the dominant process of this change. 2. The sediment traps of the pre-anthropogenic relief determined where the material originated from soil erosion was deposited: either sedimentation took place on the slopes or the filled sediment traps of the slopes rendered flood loam formation possible. Climatic influence of any importance can only be documented as the result of land use in connection with singular and/or statistic events of heavy rainfalls. Without human impact, no significant change in the Holocene landscape would have been possible.

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Este trabalho desenvolve um novo modelo Fuzzy-DEA-Game (FDG) para apoiar o estabelecimento de estratégias de produção. Esse modelo combina a Análise Envoltória de Dados (DEA) com conceitos da Teoria dos Conjuntos Fuzzy e do Jogo da Barganha de Nash. O modelo permite uma avaliação da eficiência produtiva e econômica dos produtos, o que pode resultar num portfólio de produtos mais rentáveis e de interesse do mercado consumidor. O modelo foi aplicado em uma empresa do segmento de energia. Os resultados obtidos com a aplicação do modelo FDG mostraram-se aderentes à realidade da empresa estudada e forneceram metas para a redução dos níveis de recursos (entradas) necessários para a fabricação dos produtos e para aumento dos níveis de resultados (saídas) oriundos da comercialização desses produtos. Como resultado adicional importante, o modelo FDG permitiu a identificação dos produtos do portfólio que são mais sensíveis à ocorrência de incerteza.

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O artigo analisa as relações entre os índios e os comerciantes ambulantes que, na Amazônia do século XIX, eram conhecidos como regatões. Com base em documentos da época, constata-se que nem sempre os índios foram vítimas ingênuas e passivas diante dos regatões e que é necessário enfatizar a dimensão simbólica das trocas, a fim de recuperar o protagonismo indígena nas relações estabelecidas com os comerciantes e com as mercadorias que eles vendiam.

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Analiso neste artigo as leituras que libertos e senhores fizeram da alforria e o que representavam os diferentes tipos de manumissão na experiência de liberdade em uma área mineradora periférica da América portuguesa: a vila de Rio de Contas, capitania da Bahia. Após discutir o tipo de fonte que tem sido privilegiado na maioria dos estudos sobre o tema, analiso qual tipo de alforria foi mais relevante em Rio de Contas para entender os sentidos que escravos e senhores lhe atribuíram.

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With the constant development of new antibiotics, selective pressure is a force to reckon when investigating antibiotic resistance. Although advantageous for medical treatments, it leads to increasing resistance. It is essential to use more potent and toxic antibiotics. Enzymes capable of hydrolyzing antibiotics are among the most common ways of resistance and TEM variants have been detected in several resistant isolates. Due to the rapid evolution of these variants, complex phenotypes have emerged and the need to understand their biological activity becomes crucial. To investigate the biochemical properties of TEM-180 and TEM-201 several computational methodologies have been used, allowing the comprehension of their structure and catalytic activity, which translates into their biological phenotype. In this work we intent to characterize the interface between these proteins and the several antibiotics used as ligands. We performed explicit solvent molecular dynamics (MD) simulations of these complexes and studied a variety of structural and energetic features. The interfacial residues show a distinct behavior when in complex with different antibiotics. Nevertheless, it was possible to identify some common Hot Spots among several complexes – Lys73, Tyr105 and Glu166. The structural changes that occur during the Molecular Dynamic (MD) simulation lead to the conclusion that these variants have an inherent capacity of adapting to the various antibiotics. This capability might be the reason why they can hydrolyze antibiotics that have not been described until now to be degraded by TEM variants. The results obtained with computational and experimental methodologies for the complex with Imipenem have shown that in order to this type of enzymes be able to acylate the antibiotics, they need to be capable to protect the ligand from water molecules.

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Currently multiresistant Staphylococcus aureus is one common cause of infections with high rates of morbidity and mortality worldwide, which directs scientific endeavors in search for novel antimicrobials. In this study, nine extracts from Bidens pilosa (root, stem, flower and leaves) and Annona crassiflora (rind fruit, stem, leaves, seed and pulp) were obtained with ethanol: water (7:3, v/v) and their in vitro antibacterial activity evaluated through both the agar diffusion and broth microdilution methods against 60 Oxacillin Resistant S. aureus (ORSA) strains and against S. aureus ATCC6538. The extracts from B. pilosa and A. crassiflora inhibited the growth of the ORSA isolates in both methods. Leaves of B. pilosa presented mean of the inhibition zone diameters significantly higher than chlorexidine 0.12% against ORSA, and the extracts were more active against S. aureus ATCC (p < 0.05). Parallel, toxicity testing by using MTT method and phytochemical screening were assessed, and three extracts (B. pilosa, root and leaf, and A. crassiflora, seed) did not evidence toxicity. On the other hand, the cytotoxic concentrations (CC50 and CC90) for other extracts ranged from 2.06 to 10.77 mg/mL. The presence of variable alkaloids, flavonoids, tannins and saponins was observed, even though there was a total absence of anthraquinones. Thus, the extracts from the leaves of B. pilosa revealed good anti-ORSA activity and did not exhibit toxicity.

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Um estudo taxonômico da flora de diatomáceas (Bacillariophyceae) no conteúdo estomacal de Myleus sp. (Pacú), do lago do Prato, no Arquipélago de Anavilhanas - Rio Negro -Amazônia (60° 45'W 2o 43'S) é apresentado. Foram identificados 32 táxons específicos e infraespecíficos, distribuídos em 10 gêneros e 5 famílias. Eunotia foi o gênero melhor representado.

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Foram realizadas análises colpocitológicas das diferentes fases do ciclo estral em 20 fêmeas adultas de cutias (Dasyprocta prymnolopha), assim como a determinação da duração da gestação em outros seis animais. As cutias foram mantidas em regime de cativeiro, nas condições climatológicas encontradas no trópico úmido da Amazônia. Os animais apresentaram reprodução do tipo poliestral continua, portanto não foi observada estação reprodutiva. A duração média dos ciclos estrais de 30,69 ± 4,65 dias e período médio de gestação de 104,33 + 0,57 dias. Com relação ao estudo da citologia esfoliativa, notou-se que no proestro houve frequência maior de células superficiais anucleadas, intermediárias e parabasals; no estro observou-se em número elevado, as células superficiais (anucleadas e nucleadas) e ausência de leucócitos; na fase de metaestro houve aumento de células intermediárias e leucócitos; no diestro, as células parabasals foram observadas em número maior de vezes.

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O camu-camu (Myrciaria dubia (H.B.K.) McVaugh), espécie nativa da Amazônia, cujos frutos apresentam elevado teor de vitamina C, normalmente é propagado através da semente o que não garante a reprodução de bons caracteres. Esta pesquisa teve por objetivo avaliar a multiplicação do camu-camu por meio de diferentes métodos de enxertias do tipo garfagem, visando a produção de material selecionado na região de Manaus, AM. As enxertias foram realizadas quando as mudas alcançaram um ano de idade com, em média, diâmetro do colo de 6 mm e altura de 80 cm, em viveiro coberto com tela de sombrite de 50 % de luminosidade. A enxertia do tipo garfagem com fenda lateral (65 %), seguida da garfagem lateral simples (52 %), foi o método que apresentou o melhor resultado na propagação assexuada do camu-camu. As garfagens de topo com fenda cheia (34 %) e fenda a cavalo (9 %) foram os métodos que registraram os mais baixos índices de pegamentos, embora a primeira não tenha diferido significativamente dos métodos que apresentaram os melhores resultados.

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Vinte e duas espécies de Elmohardyia Rafael são assinaladas para a Amazônia brasileira, incluindo um registro novo c onze espécies novas: E. amazona (Hardy); Ε. aquinoi sp.n; Ε. argyrogaster (Rafael); Ε. carrerai (Hardy); E. concava sp.n.; E. conckulata (Menezes & Rafael); E. echinata sp.n.; E. hispida sp.n.; E. immaculate sp.n.; E. lanei lanei (Hardy); Ε. manaos (Menezes & Rafael); Ε. oriximinaensis sp.n.; E. papaveroi (Rafael); E. parva sp.n.: £. praecipua (Rafael & Rosa); E. replicata (Hardy); E. roraimensis (Rafael & Rosa); E. rosalyae sp.n; E. subtilis sp.n.; E. tricuspis sp.n.; E. trinidadensis (Hardy) e E. valida sp.n. Uma chave para identificação das espécies da Amazônia brasileira é apresentada e novos dados sobre registros geográficos são fornecidos.

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Update to Procurement Guidance Note 03/11 - Award of Contracts without a Competition

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Skin cancer is the diagnosis for about a quarter of all patients with cancer and because most of the work is done on an outpatient basis the true extent of the disease has largely gone unrecognised. Skin cancers are related to ultraviolet radiation exposure. Geographic latitude as well as attitude affects the amount of ultraviolet exposure and the risk of skin cancer, with people from Northern Ireland exposing themselves to higher levels of ultraviolet radiation when on holiday abroad and artificially from sunbeds. Ozone depletion is known to increase the risk of ultraviolet exposure and skin cancer. The majority of people living in Northern Ireland have pale skin and are at increased risk of developing skin cancer, as are some patients with an increased genetic risk for cancer. Some pre-existing skin lesions are known to increase the risk of developing skin cancer. Data collection on the incidence of non melanoma skin cancer in Northern Ireland was not available before the establishment of the Cancer Registry in 1993. There is however good data on the incidence of melanoma before that period. In 1974 there were 39 cases in melanoma in Northern Ireland, by 2000 this had risen by almost 500% to 185 cases. åÊ