11,866 research outputs found

    Interventions using behavioural insights to influence children's diet-related outcomes: a systematic review

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    The global prevalence of children with overweight and obesity continues to rise. Obesity in childhood has dire long-term consequences on health, social and economic outcomes. Promising interventions using behavioural insights to address obesity in childhood have emerged. This systematic review examines the effectiveness and health equity implications of interventions using behavioural insights to improve children's diet-related outcomes. The search strategy included searches on six electronic databases, reference lists of previous systematic reviews and backward searching of all included studies. One-hundred and eight papers describing 137 interventions were included. Interventions using behavioural insights were effective at modifying children's diet-related outcomes in 74% of all included interventions. The most promising approaches involved using incentives, changing defaults and modifying the physical environment. Information provision alone was the least effective approach. Health equity implications were rarely analysed or discussed. There was limited evidence of the sustainability of interventions-both in relation to their overall effectiveness and cost-effectiveness. The limited evidence on health equity, long-term effectiveness and the cost-effectiveness of these interventions limit what can be inferred for policymakers. This review synthesises the use of behavioural insights to improve children's diet-related outcomes, which can be used to inform future interventions

    Strain monitoring of tapestries: results of a three-year research project

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    The outcomes of an interdisciplinary research project between conservators and engineers investigating the strain experienced by different areas of a tapestry are described. Two techniques were used: full-field monitoring using digital image correlation (DIC) and point measurements using optical fibre sensors. Results showed that it is possible to quantify the global strain across a discrete area of a tapestry using DIC; optical fibre and other sensors were used to validate the DIC. Strain maps created by the DIC depict areas of high and low strain and can be overlaid on images of the tapestry, creating a useful visual tool for conservators, custodians and the general public. DIC identifies areas of high strain not obvious to the naked eye. The equipment can be used in situ in a historic house. In addition the work demonstrated the close relationship between relative humidity and strain

    The onset of low Prandtl number thermal convection in thin spherical shells

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    This study considers the onset of stress-free Boussinesq thermal convection in rotating spherical shells with aspect ratio η=ri/ro=0.9\eta=r_i/r_o=0.9 (rir_i and ror_o being the inner and outer radius), Prandtl numbers Pr∈[10−4,10−1]{\rm Pr} \in[10^{-4},10^{-1}], and Taylor numbers Ta∈[104,1012]{\rm Ta}\in[10^{4},10^{12}]. We are particularly interested in the form of the convective cell pattern that develops, and in its time scales, since this may have observational consequences. For a fixed Ta<109{\rm Ta}<10^{9} and by decreasing Pr{\rm Pr} from 0.1 to 10−410^{-4} a transition between spiralling columnar (SC) and equatorially-attached (EA) modes, and a transition between EA and equatorially antisymmetric or symmetric polar (AP/SP) weakly multicellular modes are found. The latter modes are preferred at very low Pr{\rm Pr}. Surprisingly, for Ta>3×109{\rm Ta}>3\times 10^{9} the unicellular polar modes become also preferred at moderate Pr∼10−2{\rm Pr}\sim10^{-2} because two new transition curves between EA and AP/SP and between AP/SP and SC modes are born at a triple-point bifurcation. The dependence on Pr{\rm Pr} and Ta{\rm Ta} of the transitions is studied to estimate the type of modes, and their critical parameters, preferred at different stellar regimes.Comment: Accepted for publication in Physical Review Fluids. Contains 17 pages, 8 figures and 3 tables. Added brief erratum correcting values used for estimates of neutron star ocean viscosit

    Polar waves and chaotic flows in thin rotating spherical shells

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    Convection in rotating spherical geometries is an important physical process in planetary and stellar systems. Using continuation methods at low Prandtl number, we find both strong equatorially asymmetric and symmetric polar nonlinear rotating waves in a model of thermal convection in thin rotating spherical shells with stress-free boundary conditions. For the symmetric waves convection is confined to high latitude in both hemispheres but is only restricted to one hemisphere close to the pole in the case of asymmetric waves. This is in contrast to what is previously known from studies in the field. These periodic flows, in which the pattern is rotating steadily in the azimuthal direction, develop a strong axisymmetric component very close to onset. Using stability analysis of periodic orbits the regions of stability are determined and the topology of the stable/unstable oscillatory flows bifurcated from the branches of rotating waves is described. By means of direct numerical simulations of these oscillatory chaotic flows, we show that these three-dimensional convective polar flows exhibit characteristics, such as force balance or mean physical properties, which are similar to flows occuring in planetary atmospheres. We show that these results may open a route to understanding unexplained features of gas giant atmospheres, in particular for the case of Jupiter. These include the observed equatorial asymmetry with a pronounced decrease at the equator (the so-called dimple), and the coherent vortices surrounding the poles recently observed by the Juno mission.Comment: Published in Physical Review Fluids (2019). Contains 2 tables and 8 figure

    Galaxy Interactions in Compact Groups II: abundance and kinematic anomalies in HCG 91c

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    Galaxies in Hickson Compact Group 91 (HCG 91) were observed with the WiFeS integral field spectrograph as part of our ongoing campaign targeting the ionized gas physics and kinematics inside star forming members of compact groups. Here, we report the discovery of HII regions with abundance and kinematic offsets in the otherwise unremarkable star forming spiral HCG 91c. The optical emission line analysis of this galaxy reveals that at least three HII regions harbor an oxygen abundance ~0.15 dex lower than expected from their immediate surroundings and from the abundance gradient present in the inner regions of HCG 91c. The same star forming regions are also associated with a small kinematic offset in the form of a lag of 5-10 km/s with respect to the local circular rotation of the gas. HI observations of HCG 91 from the Very Large Array and broadband optical images from Pan-STARRS suggest that HCG 91c is caught early in its interaction with the other members of HCG 91. We discuss different scenarios to explain the origin of the peculiar star forming regions detected with WiFeS, and show that evidence point towards infalling and collapsing extra-planar gas clouds at the disk-halo interface, possibly as a consequence of long-range gravitational perturbations of HCG 91c from the other group members. As such, HCG 91c provides evidence that some of the perturbations possibly associated with the early phase of galaxy evolution in compact groups impact the star forming disk locally, and on sub-kpc scales.Comment: 25 pages, 21 figures, MNRAS accepted. Until publication of the article, the interactive component of Figure 4 is available at this URL: http://www.mso.anu.edu.au/~fvogt/website/misc.htm
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