657 research outputs found

    Ni-doped Hibonite (CaAl12O19): A New Turquoise Blue Ceramic Pigment

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    A new structure for ceramic pigments was synthesized by a conventional solid state reaction process. It is based on Ni-doped hibonite, CaAl12O19, which assumes a turquoise-like blue colour similar to that of V-doped zircon. Hibonite is associated with anorthite, CaAl2Si2O8, acting like a fluxing agent in order to lower the synthesis temperature, and with cassiterite, SnO2, acting as a tin buffer to promote coupled Ni2+ + Sn4+ -> Al3+ + Al3+ substitution, in order to ensure the electric neutrality of the hibonite lattice. Since relatively low chromophore contents are required, this new system constitutes an interesting alternative to the common blue ceramic pigments based on cobalt aluminate spinel or vanadium-doped zircon, implying lower cost and environmental advantages. The pigments characterization was performed by X-ray powder diffraction, diffuse reflectance spectroscopy, CIELAB colourimetric analysis, and testing in ceramic glazes and bodies. The substitution of Al3+ by bigger ions, like Ni2+ and Sn4+, increases the cell volume compared to undoped hibonite and is responsible of the turquoise blue colour, as verified by UV-Vis analysis. The chromatic mechanism is due to incorporation of Ni2+ in tetrahedral coordination, likely occurring at the site M3 of the hibonite lattice, where it partially substitutes the Al3+ ion. While this product shows a strong hue as a pigment, it is not stable after severe testing in glazes and attempts to improve its colouring performance are now under development

    Frozen and Invariant Quantum Discord under Local Dephasing Noise

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    In this chapter, we intend to explore and review some remarkable dynamical properties of quantum discord under various different open quantum system models. Specifically, our discussion will include several concepts connected to the phenomena of time invariant and frozen quantum discord. Furthermore, we will elaborate on the relation of these two phenomena to the non-Markovian features of the open system dynamics and to the usage of dynamical decoupling protocols.Comment: 29 pages, 8 figure

    Factors associated with involuntary hospital admissions in technology-dependent children

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    Abstract OBJECTIVE To identify the factors associated with involuntary hospital admissions of technology-dependent children, in the municipality of Ribeirão Preto, São Paulo State, Brazil. METHOD A cross-sectional study, with a quantitative approach. After an active search, 124 children who qualified under the inclusion criteria, that is to say, children from birth to age 12, were identified. Data was collected in home visits to mothers or the people responsible for the children, through the application of a questionnaire. Analysis of the data followed the assumptions of the Generalized Linear Models technique. RESULTS 102 technology-dependent children aged between 6 months and 12 years participated in the study, of whom 57% were male. The average number of involuntary hospital admissions in the previous year among the children studied was 0.71 (±1.29). In the final model the following variables were significantly associated with the outcome: age (OR=0.991; CI95%=0.985-0.997), and the number of devices (OR=0.387; CI95%=0.219-0.684), which were characterized as factors of protection and quantity of medications (OR=1.532; CI95%=1.297-1.810), representing a risk factor for involuntary hospital admissions in technology-dependent children. CONCLUSION The results constitute input data for consideration of the process of care for technology-dependent children by supplying an explanatory model for involuntary hospital admissions for this client group

    (In)dependência funcional na dependente relação de homens tetraplégicos com seus (in)substituíveis pais/cuidadores

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    Objetivou-se identificar elementos da classificação internacional de funcionalidade, incapacidade e saúde, aplicáveis ao cuidado domiciliar de homens adultos tetraplégicos, com vistas à redução da dependência de ajuda de seus pais para as atividades da vida diária, e o autocuidado. Os dados foram coletados de junho de 2004 a março de 2005, a partir de entrevista semi-estruturada, realizada com 8 adultos acometidos de lesão medular alta, e com experiência de usuários do cuidado domiciliar. Optou-se pela análise de conteúdo, a partir das categorias de significados pautadas nos seguintes resultados: suporte familiar: segurança para as funções corporais do incapacitado; tecnologia assistiva: inventividades para promoção da qualidade do cuidado; medos, futuro incerto e perda dos pais: limiares e fragilidades humanas; e ganhos funcionais: respostas objetivas das funções corporais. Conclui-se que o apoio da família e, em especial, a presença dos pais, são fundamentais para enfrentar as limitações e reagir na busca de equilíbrio na deficiência, incapacidade, desvantagem e saúde dessa clientela, preparando-a para o alcance de gradativos ganhos funcionais e independência para atividades cotidianas e autocuidado.El estudio tuvo como objetivo identificar elementos de la clasificación internacional de funcionalidad, incapacidad y salud, aplicables al cuidado domiciliario de hombres adultos cuadripléjicos, con el fin de reducir la dependencia de la ayuda de sus padres en las actividades de la vida diaria y el autocuidado. Los datos fueron reunidos entre junio de 2004 y marzo de 2005, sobre la base de una entrevista semiestructurada efectuada a 8 adultos que sufrían de lesión medular alta y que recibían normalmente cuidado domiciliario. Se optó por el sistema de análisis de contenidos a partir de las categorías de significados pautados en los siguientes resultados: apoyo familiar: seguridad para las funciones corporales del discapacitado; tecnología de apoyo: soporte tecnológico para optimizar la calidad de los cuidados; miedos; futuro incierto y pérdida de los padres: los umbrales y las fragilidades humanas; y ganancias funcionales: respuestas objetivas de las funciones corporales. Se concluyó en que el apoyo familiar y, en particular, la presencia de los padres, son fundamentales para enfrentar las limitaciones y reaccionar en la búsqueda de equilibrios en la deficiencia, incapacidad, desventajas y salud de tales pacientes, preparándolos para alcanzar en forma gradual mejoras funcionales e independencia para realizar actividades diarias y ocuparse del autocuidado.The objective of this study was to identify elements of the international classification of functioning, disability and health, applicable to quadriplegic men's home care, to reduce the dependence on their parents' help for activities of daily living and self-care. Data were collected from June 2004 to March 2005. Semi-structured interviews were performed with eight adults with high spinal cord lesions who were being cared for at home . Content analysis was performed based on the categories of meaning extrapolated and the following themes were discovered : family support: safety for the corporal functions of the disabled; supporting technology: inventiveness to promote quality care; fears, uncertain future and parents' loss: thresholds and human fragilities; and functional gains: objective response of body functions. In conclusion, family support, and especially the presence of parents, is fundamental to facing limitations and to reacting in the search for balance with the deficiency, disability, disadvantage and health of that population, preparing them to achieve gradual functional gain and independence for daily activities and self-care

    Search for supersymmetric particles in scenarios with a gravitino LSP and stau NLSP

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    Sleptons, neutralinos and charginos were searched for in the context of scenarios where the lightest supersymmetric particle is the gravitino. It was assumed that the stau is the next-to-lightest supersymmetric particle. Data collected with the DELPHI detector at a centre-of-mass energy near 189 GeV were analysed combining the methods developed in previous searches at lower energies. No evidence for the production of these supersymmetric particles was found. Hence, limits were derived at 95% confidence level.Comment: 31 pages, 14 figure

    Model-independent evidence for J/ψpJ/\psi p contributions to Λb0J/ψpK\Lambda_b^0\to J/\psi p K^- decays

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    The data sample of Λb0J/ψpK\Lambda_b^0\to J/\psi p K^- decays acquired with the LHCb detector from 7 and 8~TeV pppp collisions, corresponding to an integrated luminosity of 3 fb1^{-1}, is inspected for the presence of J/ψpJ/\psi p or J/ψKJ/\psi K^- contributions with minimal assumptions about KpK^- p contributions. It is demonstrated at more than 9 standard deviations that Λb0J/ψpK\Lambda_b^0\to J/\psi p K^- decays cannot be described with KpK^- p contributions alone, and that J/ψpJ/\psi p contributions play a dominant role in this incompatibility. These model-independent results support the previously obtained model-dependent evidence for Pc+J/ψpP_c^+\to J/\psi p charmonium-pentaquark states in the same data sample.Comment: 21 pages, 12 figures (including the supplemental section added at the end

    Quantum numbers of the X(3872)X(3872) state and orbital angular momentum in its ρ0Jψ\rho^0 J\psi decay

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    Angular correlations in B+X(3872)K+B^+\to X(3872) K^+ decays, with X(3872)ρ0J/ψX(3872)\to \rho^0 J/\psi, ρ0π+π\rho^0\to\pi^+\pi^- and J/ψμ+μJ/\psi \to\mu^+\mu^-, are used to measure orbital angular momentum contributions and to determine the JPCJ^{PC} value of the X(3872)X(3872) meson. The data correspond to an integrated luminosity of 3.0 fb1^{-1} of proton-proton collisions collected with the LHCb detector. This determination, for the first time performed without assuming a value for the orbital angular momentum, confirms the quantum numbers to be JPC=1++J^{PC}=1^{++}. The X(3872)X(3872) is found to decay predominantly through S wave and an upper limit of 4%4\% at 95%95\% C.L. is set on the fraction of D wave.Comment: 16 pages, 4 figure

    TRY plant trait database - enhanced coverage and open access

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    Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
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