330 research outputs found

    A theoretical analysis of the free vibration of discretely stiffened cylindrical shells with arbitrary end conditions

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    Theoretical analysis of free vibration of discretely stiffened cylindrical shells with arbitrary end condition

    Species Richness, Species Identity and Ecosystem Function in Managed Temperate Grasslands

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    Manipulation of plant species diversity may provide a way to improve the ecosystem functioning of managed systems by increasing productivity and suppressing weedy species. As yet, the functional role of species richness is not well-enough understood to enable practical application. We investigated the effects of differing species richness on community stability and invasion resistance in a grazed temperate grassland

    Intake and Milk Production of Lactating Dairy Cows Grazing Diverse Forage Mixtures Over Two Grazing Seasons

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    Voluntary intake and stocking rate are key determinants of animal performance on pasture. Greater plant diversity in grassland plant communities has been linked to increased primary production, greater stability in response to disturbance, and reduced weed pressure. Thus, increasing plant diversity may be one approach to improving animal productivity. An experiment was conducted to determine the effects of forage diversity on intake and milk production of lactating dairy cows over two grazing seasons

    Diverse Forage Mixtures Effect on Herbage Yield, Sward Composition, and Dairy Cattle Performance

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    Managing complex mixtures of plants to take advantage of spatial and temporal variability in land and climate may be one ecological approach to increase productivity of pastures. We tested the hypothesis that complex mixtures of forage species would yield more herbage and reduce weed competition compared with a simple grass-legume mixture in grazed pastures

    Managing Interspecies Competition to Improve Spring Pasture

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    Orchardgrass (Dactylis glomerata L.) is one of the earliest maturing pasture grasses utilized in the northeastern United States. However, wet springs can delay forage harvesting resulting in advanced forage maturity and reduction in nutritive value. Chicory (Cichorium intybus L.) is a tall, upright-growing forb that shows promise as a high-energy companion crop to orchardgrass and may delay orchardgrass maturity through shading effects on plant morphology. The objective of this study was to evaluate monocultures and mixtures of orchardgrass, chicory, and white clover (Trifolium repens L.) over two consecutive springs to determine the effects of species diversity on plant maturity, nutritive characteristics, and botanical composition of forage mass. Forage monocultures and mixtures were planted in central Pennsylvania in August 2018 and were observed for two years with three harvests occurring each year (one each in spring, summer, and fall). In the first spring, orchardgrass demonstrated nine days delay in maturity when grown with chicory as compared to when grown in monocultures or in orchardgrass-white clover mixtures. Although orchardgrass was at an earlier developmental stage, fiber concentrations were similar when grown with or without chicory. Additionally, in the first spring, orchardgrass mixtures containing chicory had 1.5x greater forage mass than orchardgrass monocultures and orchardgrass-white clover mixtures. Chicory biomass was low in the second spring, likely due to winterkill following a late fall harvest the previous year, resulting in a negligible effect on orchardgrass. However, orchardgrass-chicory-white clover mixtures (even with low amounts of chicory in the second year) had the greatest forage mass and nutritive value yield over both years, indicating that these mixtures can provide greater agronomic benefits than orchardgrass monocultures

    Respiratory protein interactions in Dehalobacter sp. strain 8M revealed through genomic and native proteomic analyses

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    Dehalobacter (Firmicutes) encompass obligate organohalide-respiring bacteria used for bioremediation of groundwater contaminated with halogenated organics. Various aspects of their biochemistry remain unknown, including the identities and interactions of respiratory proteins. Here, we sequenced the genome of Dehalobacter sp. strain 8M and analysed its protein expression. Strain 8M encodes 22 reductive dehalogenase homologous (RdhA) proteins. RdhA D8M_v2_40029 (TmrA) was among the two most abundant proteins during growth with trichloromethane and 1,1,2-trichloroethane. To examine interactions of respiratory proteins, we used blue native gel electrophoresis together with dehalogenation activity tests and mass spectrometry. The highest activities were found in gel slices with the highest abundance of TmrA. Protein distributions across gel lanes provided biochemical evidence that the large and small subunits of the membrane-bound [NiFe] uptake hydrogenase (HupL and HupS) interacted strongly and that HupL/S interacted weakly with RdhA. Moreover, the interaction of RdhB and membrane-bound b-type cytochrome HupC was detected. RdhC proteins, often encoded in rdh operons but without described function, migrated in a protein complex not associated with HupL/S or RdhA. This study provides the first biochemical evidence of respiratory protein interactions in Dehalobacter, discusses implications for the respiratory architecture and advances the molecular comprehension of this unique respiratory chain

    Capacity Value of Wind Power

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    Power systems are planned such that they have adequate generation capacity to meet the load, according to a defined reliability target. The increase in the penetration of wind generation in recent years has led to a number of challenges for the planning and operation of power systems. A key metric for generation system adequacy is the capacity value of generation. The capacity value of a generator is the contribution that a given generator makes to generation system adequacy. The variable and stochastic nature of wind sets it apart from conventional energy sources. As a result, the modeling of wind generation in the same manner as conventional generation for capacity value calculations is inappropriate. In this paper a preferred method for calculation of the capacity value of wind is described and a discussion of the pertinent issues surrounding it is given. Approximate methods for the calculation are also described with their limitations highlighted. The outcome of recent wind capacity value analyses in Europe and North America, along with some new analysis, are highlighted with a discussion of relevant issues also given

    Os planos municipais de saúde como ferramenta de gestão e planejamento: um levantamento bibliométrico a respeito da produção acadêmica / Municipal health plans as a management and planning tool: a bibliometric survey about academic production

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    A revisão do estado da arte na área de Política, Planejamento e Gestão em Saúde (PPGS) é primordial para o desenvolvimento de estudos científicos, pois permite conhecer tendências, lacunas e desafios que se colocam para os pesquisadores, estudantes e gestores do sistema de saúde. O presente trabalho tem como objetivo delinear o perfil da produção científica a respeito dos Planos Municipais de saúde, considerando as dissertações e teses de doutorado. A pesquisa foi conduzida mediante a adoção da abordagem bibliométrica. A escolha da amostra está baseada em teses e dissertações. Nesse sentido, apropriou-se das publicações disponíveis no banco de teses do Portal de Periódicos da Capes/MEC. Na presente pesquisa foram analisados 10 trabalhos, sendo 09 dissertações e 01 tese de doutorado, houve concentração de trabalhos entre os anos de 2016 e 2020, a área de conhecimento ficou dividida entre Saúde Pública e Administração e planejamento em saúde, a metodologia mais utilizado foi a qualitativa, com análise documental e entrevistas semiestruturados, com abordagem metodológica em estudo de caso. Ficou evidente na pesquisa, o pouco envolvimento das universidades para pesquisar a respeito da temática
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