1,971 research outputs found

    Nanodroplets Impacting on Graphene

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    The unique and remarkable properties of graphene can be exploited as the basis to a wide range of applications. However, in spite of years of investigations there are some important graphene properties that are not still fully understood, as for example, its wettability. There are controversial reported results whether graphene is really hydrophobic or hydrophilic. In order to address this problem we have carried out classical molecular dynamics simulations of water nanodroplets shot against graphene surface. Our results show that the contact angle values between the nanodroplets and graphene surfaces depend on the initial droplet velocity value and these angles can change from 86 degrees (hydrophobic) to 35 degrees (hydrophilic). Our preliminary results indicate that the graphene wettability can be dependent on spreading liquid dynamics and which can explain some of the apparent inconsistencies reported in the literature

    A conceptual study of spirituality in selected writings of Emile Jaques-Dalcroze

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    Several authors have noted that one of Émile Jaques-Dalcroze’s aims was to dissolve the mind–body dualism, typical of Cartesianism. However, there has been little research on the spirit–body connection, as it appears in Jaques-Dalcroze’s writings. The purpose of this document analysis is to understand how a hermeneutic phenomenological model for spirituality in music education can inform our understanding of spirituality in selected writings by Jaques-Dalcroze. In the adapted model holism, balance, aesthetic experience, and movement in time, space, and with energy emerged as core concepts. This gives us a much richer understanding of the Dalcroze approach than has hitherto been available and adds to a growing narrative about the spiritual as it pertains to Jaques-Dalcroze and the approach he initiated

    Hydrogen Motion in Magnesium Hydride by NMR

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    In coarse-grained MgH2, the diffusive motion of hydrogen remains too slow (<10^5 hops s^−1) to narrow the H NMR line up to 400 °C. Slow-motion dipolar relaxation time T1D measurements reveal the motion, with hopping rate ωH from 0.1 to 430 s^−1 over the range of 260 to 400 °C, the first direct measurement of H hopping in MgH2. The ωH data are described by an activation energy of 1.72 eV (166 kJ/mol) and attempt frequency of 2.5 × 10^15 s^−1. In ball-milled MgH2 with 0.5 mol % added Nb2O5 catalyst, line-narrowing is evident already at 50 °C. The line shape shows distinct broad and narrow components corresponding to immobile and mobile H, respectively. The fraction of mobile H grows continuously with temperature, reaching ∼30% at 400 °C. This demonstrates that this material’s superior reaction kinetics are due to an increased rate of H motion, in addition to the shorter diffusion paths from ball-milling. In ball-milled MgH2 without additives, the line-narrowed component is weaker and is due, at least in part, to trapped H2 gas. The spin−lattice relaxation rates T1^−1 of all materials are compared, with ball-milling markedly increasing T1^−1. The weak temperature dependence of T1^−1 suggests a mechanism with paramagnetic relaxation centers arising from the mechanical milling

    Análise e melhoria de processo do Serviço de Atendimento ao Cidadão (SAC) da Embrapa Florestas.

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    bitstream/CNPF-2009-09/42630/1/Doc156.pdf1 CD-RO

    Fractura triplana epifisaria distal de tibia: a propósito de un caso con interposición de periostio

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    Se presenta un caso de fractura triplana en 2 fragmentos en un paciente varón de 13 años tratado quirúrgicamente, observando la interposición perióstica en el plano axial a nivel del fragmento antero-externo, que impedía la reducción anatómica de la zona epifisaria articular. Se analiza la anatomía quirúrgica de las fracturas triplanas considerando que esta lesión puede ser más frecuente de lo que se ha informado, y sólo valorada en los casos en que se emplee un abordaje antero-externo.The case of a 13-year-old boy with a two-fragment triplane fracture of the distal epiphysis of the tibia is presented. At surgery, an interposition of the periosteum in the axial plane behind the antero-lateral fragment, preventing the anatomical reduction of the epiphyseal joint surface was found. The surgical anatomy of triplane fractures is review taking into account that this lesion can be more frequent that it has been reported. The true incidence should be evaluated at surgery by antero-lateral approach

    Integration of professional judgement and decision-making in high-level adventure sports coaching practice

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    This study examined the integration of professional judgement and decision-making processes in adventure sports coaching. The study utilised a thematic analysis approach to investigate the decision-making practices of a sample of high-level adventure sports coaches over a series of sessions. Results revealed that, in order to make judgements and decisions in practice, expert coaches employ a range of practical and pedagogic management strategies to create and opportunistically use time for decision-making. These approaches include span of control and time management strategies to facilitate the decision-making process regarding risk management, venue selection, aims, objectives, session content, and differentiation of the coaching process. The implication for coaches, coach education, and accreditation is the recognition and training of the approaches that“create time” for the judgements in practice, namely“creating space to think”. The paper concludes by offering a template for a more expertise-focused progression in adventure sports coachin

    Fracturas del macizo trocantéreo. Estudio comparativo Ender-DHS: revision de 114 casos

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    Se presenta un estudio retrospectivo de 114 fracturas pertrocantéreas tratadas con enclavado elástico de Ender (71) y tornillo placa deslizante, DHS (43). Se efectuó un estudio estadístico descriptivo-comparativo entre los 2 grupos de pacientes según la técnica quirúrgica empleada. Se constató un mayor índice de estabilidad usando el DHS (81%), frente al 6 1 % del otro grupo. La tasa de complicaciones fue del 16% y 55% respectivamente. Los resultados clínicos fueron mejores en los enfermos tratados con DHS, fundamentalmente en cuanto a la deambulación que se consiguió en el 98% (Ender 75%), ausencia de dolor y movilidad conservada. Los autores piensan que la estabilidad preoperatoria no influye en la solidez del montaje usando el DHS, pero con la técnica de Ender ésta disminuye en las fracturas inestables; por ello, la técnica de Ender estaría solamente indicada en el tratamiento de fracturas estables en pacientes de edad avanzada o con mal estado general, aunque en clara competencia con el DHS.A retrospective study of 114 intertrochanteric fractures operated on either with Ender's rods (71) or dynamic hip screws, DHS (43) is presented. A statistical descriptive-comparative study between the 2 groups was attempted. There was a greater index of stability using the DHS (82%) than Ender's rods (61%). The rate of complications was 16% and 55% respectively. The clinical outcome was better in cases treated with DHS, specially for walking ability, which was regained in the 98% of cases (Ender 75%), painless and preserved mobility. The authors think that the stability before operation do not influence the solidity of the assembly using the DHS device. On the contrary, with the Ender's technique the fixation is no satisfactory in unstables fractures. Ender's rods would only be suitable for treatment of stable fractures in older patient or with serious associated diseases, although in clear competition with the DHS
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