23,924 research outputs found

    'If I had had a me': the benefits and challenges of involving children with lived experience in youth justice services

    Get PDF
    This article presents the findings from an ongoing evaluation of a partnership project between a youth justice service and an independent charity which supports the involvement of children with lived experience of youth justice services in work with other young people who have offended and with policy makers and service providers. The research involved the secondary analysis of project records and 15 semi-structured interviews with youth justice managers and practitioners and the charity's staff as well as representatives from external organisations with whom it has worked. The analysis focuses on the nature of activities undertaken, the 'theory of change' driving these activities, the perceived benefits of the work as well as some of the challenges involved. The findings suggest positive outcomes for children in terms of increased engagement and participation, improvements in confidence and self-esteem and the development of personal, social, health and educational skills. The project represents a compelling example of what child first diversion looks like in practice. The article adds to existing knowledge of the benefits and challenges of involving children with recent experience of the youth justice system in service delivery and in co-production work with policy makers and service providers. It also offers insights into recent changes in youth justice policy in England and Wales, in particular the commitment to treating children as children first

    An evaluation of Youth Ink: Interim report

    Get PDF
    Interim report on an evaluation of a charity which engages young people with lived experience of youth crime and the youth justice system to advise and support young people who are under the supervision of the local youth justice service

    Grazing-angle scattering of electromagnetic waves in gratings with varying mean parameters: grating eigenmodes

    Get PDF
    A highly unusual pattern of strong multiple resonances for bulk electromagnetic waves is predicted and analysed numerically in thick periodic holographic gratings in a slab with the mean permittivity that is larger than that of the surrounding media. This pattern is shown to exist in the geometry of grazing-angle scattering (GAS), that is when the scattered wave (+1 diffracted order) in the slab propagates almost parallel to the slab (grating) boundaries. The predicted resonances are demonstrated to be unrelated to resonant generation of the conventional guided modes of the slab. Their physical explanation is associated with resonant generation of a completely new type of eigenmodes in a thick slab with a periodic grating. These new slab eigenmodes are generically related to the grating; they do not exist if the grating amplitude is zero. The field structure of these eigenmodes and their dependence on structural and wave parameters is analysed. The results are extended to the case of GAS of guided modes in a slab with a periodic groove array of small corrugation amplitude and small variations in the mean thickness of the slab at the array boundaries.Comment: 16 pages, 6 figure

    Coherent imaging of a pure phase object with classical incoherent light

    Get PDF
    By using the ghost imaging technique, we experimentally demonstrate the reconstruction of the diffraction pattern of a {\em pure phase} object by using the classical correlation of incoherent thermal light split on a beam splitter. The results once again underline that entanglement is not a necessary feature of ghost imaging. The light we use is spatially highly incoherent with respect to the object (2μ\approx 2 \mum speckle size) and is produced by a pseudo-thermal source relying on the principle of near-field scattering. We show that in these conditions no information on the phase object can be retrieved by only measuring the light that passed through it, neither in a direct measurement nor in a Hanbury Brown-Twiss (HBT) scheme. In general, we show a remarkable complementarity between ghost imaging and the HBT scheme when dealing with a phase object.Comment: 13 pages, 11 figures. Published in Physical Review A. Replaced version fixes some problems with Figs. 1, 4 and 1

    Anisotropic multi-gap superfluid states in nuclear matter

    Full text link
    It is shown that under changing density or temperature a nucleon Fermi superfluid can undergo a phase transition to an anisotropic superfluid state, characterized by nonvanishing gaps in pairing channels with singlet-singlet (SS) and triplet-singlet (TS) pairing of nucleons (in spin and isospin spaces). In the SS pairing channel nucleons are paired with nonzero orbital angular momentum. Such two-gap states can arise as a result of branching from the one-gap solution of the self-consistent equations, describing SS or TS pairing of nucleons, that depends on the relationship between SS and TS coupling constants at the branching point. The density/temperature dependence of the order parameters and the critical temperature for transition to the anisotropic two-gap state are determined in a model with the SkP effective interaction. It is shown that the anisotropic SS-TS superfluid phase corresponds to a metastable state in nuclear matter.Comment: Prepared with RevTeX4, 7p., 5 fi

    Reconnection in Marginally Collisionless Accretion Disk Coronae

    Full text link
    We point out that a conventional construction placed upon observations of accreting black holes, in which their nonthermal X-ray spectra are produced by inverse comptonization in a coronal plasma, suggests that the plasma is marginally collisionless. Recent developments in plasma physics indicate that fast reconnection takes place only in collisionless plasmas. As has recently been suggested for the Sun's corona, such marginal states may result from a combination of energy balance and the requirements of fast magnetic reconnection.Comment: Revised in response to referee. Accepted ApJ. 11 pp., no figures. Uses aastex 5.0

    Experimental evidence of high-resolution ghost imaging and ghost diffraction with classical thermal light

    Get PDF
    High-resolution ghost image and ghost diffraction experiments are performed by using a single source of thermal-like speckle light divided by a beam splitter. Passing from the image to the diffraction result solely relies on changing the optical setup in the reference arm, while leaving untouched the object arm. The product of spatial resolutions of the ghost image and ghost diffraction experiments is shown to overcome a limit which was formerly thought to be achievable only with entangled photons.Comment: 5 pages, 4 figure

    Resolving long-range spatial correlations in jammed colloidal systems using photon correlation imaging

    Get PDF
    We introduce a new dynamic light scattering method, termed photon correlation imaging, which enables us to resolve the dynamics of soft matter in space and time. We demonstrate photon correlation imaging by investigating the slow dynamics of a quasi two-dimensional coarsening foam made of highly packed, deformable bubbles and a rigid gel network formed by dilute, attractive colloidal particles. We find the dynamics of both systems to be determined by intermittent rearrangement events. For the foam, the rearrangements extend over a few bubbles, but a small dynamical correlation is observed up to macroscopic length scales. For the gel, dynamical correlations extend up to the system size. These results indicate that dynamical correlations can be extremely long-ranged in jammed systems and point to the key role of mechanical properties in determining their nature.Comment: Published version (Phys. Rev. Lett. 102, 085702 (2009)) The Dynamical Activity Mapsprovided as Supplementary Online Material are also available on http://w3.lcvn.univ-montp2.fr/~lucacip/dam/movies.ht

    Asymptotics of Quantum Relative Entropy From Representation Theoretical Viewpoint

    Full text link
    In this paper it was proved that the quantum relative entropy D(σρ)D(\sigma \| \rho) can be asymptotically attained by Kullback Leibler divergences of probabilities given by a certain sequence of POVMs. The sequence of POVMs depends on ρ\rho, but is independent of the choice of σ\sigma.Comment: LaTeX2e. 8 pages. The title was changed from "Asymptotic Attainment for Quantum Relative Entropy
    corecore