659 research outputs found

    A theorem for the beam splitter entangler

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    It is conjectured that the an entanglement output states from a beam splitter requires the nonclassicality in the input state(M.S. Kim, W. Son, V. Buzek and P. L. Knight, Phys. Rev. A, 65, 032323(2002)). Here we give a proof for this conjecture.Comment: Two relevant literatures added. To appear in Phys. Rev.

    Anthropogenic Matrices Favor Homogenization Of Tree Reproductive Functions In A Highly Fragmented Landscape

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    Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Species homogenization or floristic differentiation are two possible consequences of the fragmentation process in plant communities. Despite the few studies, it seems clear that fragments with low forest cover inserted in anthropogenic matrices are more likely to experience floristic homogenization. However, the homogenization process has two other components, genetic and functional, which have not been investigated. The purpose of this study was to verify whether there was homogenization of tree reproductive functions in a fragmented landscape and, if found, to determine how the process was influenced by landscape composition. The study was conducted in eight fragments in southwest Brazil. The study was conducted in eight fragments in southwestern Brazil. In each fragment, all individual trees were sampled that had a diameter at breast height ≥3 cm, in ten plots (0.2 ha) and, classified within 26 reproductive functional types (RFTs). The process of functional homogenization was evaluated using additive partitioning of diversity. Additionally, the effect of landscape composition on functional diversity and on the number of individuals within each RFT was evaluated using a generalized linear mixed model. appeared to be in a process of functional homogenization (dominance of RFTs, alpha diversity lower than expected by chance and and low beta diversity). More than 50% of the RFTs and the functional diversity were affected by the landscape parameters. In general, the percentage of forest cover has a positive effect on RFTs while the percentage of coffee matrix has a negative one. The process of functional homogenization has serious consequences for biodiversity conservation because some functions may disappear that, in the long term, would threaten the fragments. This study contributes to a better understanding of how landscape changes affect the functional diversity, abundance of individuals in RFTs and the process of functional homogenization, as well as how to manage fragmented landscapes. © 2016 Carneiro et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.1110CAPES, Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorCCFC, Crohn's and Colitis Foundation of CanadaCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Properties of a beam splitter entangler with Gaussian input states

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    An explicit formula is given for the quantity of entanglement in the output state of a beam splitter, given the squeezed vacuum states input in each mode.Comment: To appear in Phys. Rev.

    Enivironmental management in project oriented companies

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    Construction industry is a typical project-oriented industrial sector. For a contracting company, production has a project character and starts only after the contract between the client and the contracting company has been signed. Construction activities are associated with a range of various adverse environmental impacts, such as noise, raw material consumption, energy consumption, emissions into air, water and ground and fuel consumption of construction machinery. In order to control and mitigate these adverse phenomena, an environmental management system needs to be implemented into a construction company.\ud The paper will review the main environmental effects of the construction project. A comprehensive conceptual model that extends the concept of quality into the area of sustainability is supplemented with Environmental Impact Assessment for a given construction project. In the last part, the paper provides an overview of the implementation of environmental management systems into construction industry on the basis of a recently conducted survey

    Sustainable procurement practices in the Brazilian chemical industry context

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    Sustainable procurement requires an understanding of the full impact of purchase throughout the entire life cycle of the product or service, irrespective of location. The aim is to investigate the adoption of sustainable procurement in some Brazilian chemical companies. Questionnaires were sent to professionals from the Brazilian Chemical Industry Association (ABIQUIM) and from thirtyseven associated companies. The results were used to elaborate empirical illustrations about sustainable procurement practices in the Brazilian chemical industry context. Although the companies did not have a prescriptive supplier selection model that incorporates social-environmental criteria, most companies had more restrictive standards than the legislation and they supported suppliers to improve their social-environmental performance. In addition, that actions related to social and environmental issues occur in policies and documents and are reflected through middle and upper management commitments. It indicates that there are some organizational directions to incorporate social and environmental questions. However, no materialization in actions along the procurement process

    Mamiferos da Fazenda Nhumirim, sub-região de Nhecolándia, Pantanal do Mato Grosso do Sul : I - levantamento preliminar de espécies

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    Trabalho conduzido na Fazenda Nhumirim, Centro de Pesquisa Agropecuária do Pantanal, EMBRAPA, com auxílio da OEA - Organização dos Estados Americanos, através do CNPq, fornecido ao Dr. Cleber J.R. Alho (Conta nº 03-85-528-517-BR-1)The pantanal is one of the world's richest freshwater wetlands. The pantanal is located in the flood plain of the headwaters of the Paraguai river, covering 140,000km2. The habitats of the Pantanal are present in a complex mosaic. The major habitat types are: pockets of forests, called capão or cordilheira, seasonally flooded grasslands or campos, and permanent or temporary lagoons, called baías. The Pantanal harbors both rich and abundant mammal fauna. A survey was conducted at Fazenda Nhumirim, a research station run by the Centro de Pesquisa Agropecuária do Pantanal (CPAP) in Corumbá, a research branch of EMBRAPA. The Fazenda covers an area of 4,310 ha in the sub-region of Nhecolândia, appoximately 150km east of Corumbá, Mato Grosso do Sul. The area receives an average annual rainfall of 1,022mm, and has a mean monthly temperature that varies between 29.1ºC (January) and 22.0ºC (June). Four routes were followed between two times during ten days of each month. The survey routes were covered on horseback by between two and four observers. Each route was followed and equal number of times in the morning and in the afternoon, to eliminate bias related to the activity patterns of mammals. In order to evaluate relative abundance of nocturnal species, we also conducted a number of nocturnal censuses. These censuses were done by car; a high intensity searchlight was used to spot the animals. We also conducted a trap-mark-recapture survey of the small mammals at Fazenda Nhumirim. After the census period, we continued to collect observations on the occurrence of mammals at the Fazenda, noting wherever possible the kind of habitat in which the animals were observed. The survey identified a diversity of mammals at Fazenda Nhumirim: six orders, 14 families, 19 genera, and 20 species. Nasua nasua was the most frequently observed species during the diurnal census, accounting for 61.5 percent of all observations. Dusicyon (formely Cerdocyon) thous was the most frequently observed species on the nocturnal census (39.13%). The small mammal community of Fazenda Nhumirim is composed of seven species: one marsupial, four cricetine rodents and two echimyid rodents

    Exploring the transferability of large supramolecular assemblies to the vacuum-solid interface

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    We present an interplay of high-resolution scanning tunneling microscopy imaging and the corresponding theoretical calculations based on elastic scattering quantum chemistry techniques of the adsorption of a gold-functionalized rosette assembly and its building blocks on a Au(111) surface with the goal of exploring how to fabricate functional 3-D molecular nanostructures on surfaces. The supramolecular rosette assembly stabilized by multiple hydrogen bonds has been sublimed onto the Au(111) surface under ultra-high vacuum conditions; the resulting surface nanostructures are distinctly different from those formed by the individual molecular building blocks of the rosette assembly, suggesting that the assembly itself can be transferred intact to the surface by in situ thermal sublimation. This unanticipated result will open up new perspectives for growth of complex 3-D supramolecular nanostructures at the vacuum-solid interface

    Density and biomass estimates by removal for an amazonian crocodilian, paleosuchus palpebrosus

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    Direct counts of crocodilians are rarely feasible and it is difficult to meet the assumptions of mark-recapture methods for most species in most habitats. Catch-out experiments are also usually not logistically or morally justifiable because it would be necessary to destroy the habitat in order to be confident that most individuals had been captured. We took advantage of the draining and filling of a large area of flooded forest during the building of the Santo Antônio dam on the Madeira River to obtain accurate estimates of the density and biomass of Paleosuchus palpebrosus. The density, 28.4 non-hatchling individuals per km2 , is one of the highest reported for any crocodilian, except for species that are temporarily concentrated in small areas during dry-season drought. The biomass estimate of 63.15 kg∗km-2 is higher than that for most or even all mammalian carnivores in tropical forest. P. palpebrosus may be one of the World?s most abundant crocodilians. © 2016 Campos, Magnusson. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
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