63 research outputs found

    Molecular dynamics simulation of the fragile glass former ortho-terphenyl: a flexible molecule model

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    We present a realistic model of the fragile glass former orthoterphenyl and the results of extensive molecular dynamics simulations in which we investigated its basic static and dynamic properties. In this model the internal molecular interactions between the three rigid phenyl rings are described by a set of force constants, including harmonic and anharmonic terms; the interactions among different molecules are described by Lennard-Jones site-site potentials. Self-diffusion properties are discussed in detail together with the temperature and momentum dependencies of the self-intermediate scattering function. The simulation data are compared with existing experimental results and with the main predictions of the Mode Coupling Theory.Comment: 20 pages and 28 postscript figure

    Diffusion in crowded biological environments: applications of Brownian dynamics

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    Biochemical reactions in living systems occur in complex, heterogeneous media with total concentrations of macromolecules in the range of 50 - 400 mgml. Molecular species occupy a significant fraction of the immersing medium, up to 40% of volume. Such complex and volume-occupied environments are generally termed 'crowded' and/or 'confined'. In crowded conditions non-specific interactions between macromolecules may hinder diffusion - a major process determining metabolism, transport, and signaling. Also, the crowded media can alter, both qualitatively and quantitatively, the reactions in vivo in comparison with their in vitro counterparts. This review focuses on recent developments in particle-based Brownian dynamics algorithms, their applications to model diffusive transport in crowded systems, and their abilities to reproduce and predict the behavior of macromolecules under in vivo conditions

    Effects of school-based interventions on mental health stigmatization: a systematic review

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    Stigmatizing, or discriminatory, perspectives and behaviour, which target individuals on the basis of their mental health, are observed in even the youngest school children. We conducted a systematic review of the published and unpublished, scientific literature concerning the benefits and harms of school-based interventions, which were directed at students 18 years of age or younger to prevent or eliminate such stigmatization. Forty relevant studies were identified, yet only a qualitative synthesis was deemed appropriate. Five limitations within the evidence base constituted barriers to drawing conclusive inferences about the effectiveness and harms of school-based interventions: poor reporting quality, a dearth of randomized controlled trial evidence, poor methods quality for all research designs, considerable clinical heterogeneity, and inconsistent or null results. Nevertheless, certain suggestive evidence derived both from within and beyond our evidence base has allowed us to recommend the development, implementation and evaluation of a curriculum, which fosters the development of empathy and, in turn, an orientation toward social inclusion and inclusiveness. These effects may be achieved largely by bringing especially but not exclusively the youngest children into direct, structured contact with an infant, and likely only the oldest children and youth into direct contact with individuals experiencing mental health difficulties. The possible value of using educational activities, materials and contents to enhance hypothesized benefits accruing to direct contact also requires investigation. Overall, the curriculum might serve as primary prevention for some students and as secondary prevention for others

    More than just child’s play?: An experimental investigation of the impact of an appearance-focused internet game on body image and career aspirations of young girls

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    © 2017, The Author(s). In recent years, elements of the modern environment (such as television, Internet, toys and clothes) have been criticized for having an increasingly sexualized or appearance focus, which has been suggested to be detrimental to girls’ development. The current study examined the impact of an appearance-focused Internet game on young girls’ body image and career cognitions and aspirations. Eighty British girls aged 8–9 years were randomly assigned to play an appearance-focused or a non-appearance focused game for 10 minutes. Girls in the appearance-focused game condition displayed greater body dissatisfaction compared to the control condition. Type of game did not impact girls’ perceived capacity to do various jobs. However, girls who played the appearance-focused game reported a greater preference for feminine careers compared to the control group. This provides preliminary evidence that appearance-focused Internet games may be detrimental to young girls’ body image and aspirations. Internet games should be included in our consideration of influential messages for young girls
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