6,908 research outputs found

    Adaptive Mesh Refinement for Hyperbolic Systems based on Third-Order Compact WENO Reconstruction

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    In this paper we generalize to non-uniform grids of quad-tree type the Compact WENO reconstruction of Levy, Puppo and Russo (SIAM J. Sci. Comput., 2001), thus obtaining a truly two-dimensional non-oscillatory third order reconstruction with a very compact stencil and that does not involve mesh-dependent coefficients. This latter characteristic is quite valuable for its use in h-adaptive numerical schemes, since in such schemes the coefficients that depend on the disposition and sizes of the neighboring cells (and that are present in many existing WENO-like reconstructions) would need to be recomputed after every mesh adaption. In the second part of the paper we propose a third order h-adaptive scheme with the above-mentioned reconstruction, an explicit third order TVD Runge-Kutta scheme and the entropy production error indicator proposed by Puppo and Semplice (Commun. Comput. Phys., 2011). After devising some heuristics on the choice of the parameters controlling the mesh adaption, we demonstrate with many numerical tests that the scheme can compute numerical solution whose error decays as N3\langle N\rangle^{-3}, where N\langle N\rangle is the average number of cells used during the computation, even in the presence of shock waves, by making a very effective use of h-adaptivity and the proposed third order reconstruction.Comment: many updates to text and figure

    Ruptures and repairs of group therapy alliance. an untold story in psychotherapy research

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    Although previous studies investigated the characteristics of therapeutic alliance in group treatments, there is still a dearth of research on group alliance ruptures and repairs. The model by Safran and Muran was originally developed to address therapeutic alliance in individual therapies, and the usefulness of this approach to group intervention needs to be demonstrated. Alliance ruptures are possible at member to therapist, member to member, member to group levels. Moreover, repairs of ruptures in group are quite complex, i.e., because other group members have to process the rupture even if not directly involved. The aim of the current study is to review the empirical research on group alliance, and to examine whether the rupture repair model can be a suitable framework for clinical understanding and research of the complexity of therapeutic alliance in group treatments. We provide clinical vignettes and commentary to illustrate theoretical and research aspects of therapeutic alliance rupture and repair in groups. Our colleague Jeremy Safran made a substantial contribution to research on therapeutic alliance, and the current paper illustrates the enduring legacy of this work and its potential application to the group therapy context

    Magic mirror on the wall: Selfie-related behavior as mediator of the relationship between narcissism and problematic smartphone use

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    Objective: Recent research has suggested that problematic smartphone use is associated with several psychological factors and that mobile apps and smartphone-related behavior (i.e. selfi e behavior) may encourage the development of problematic smartphone use. However, little is known about how the interplay between dysfunctional personality characteristics and selfi e-related behavior can infl uence problematic smartphone use. The aim of this study was to examine the relationship between narcissism and problematic smartphone use, as well as the mediating role of selfi e-related behavior in this relationship among young men and women. Method: In the current study, a total of 627 undergraduate students (283 males and 344 females) completed a cross-sectional survey. A structural equation model was tested separately for males and females in order to evaluate the associations between narcissism, selfi e-related behavior and problematic smartphone use. Results: The results showed that greater narcissism was related to increased selfi e-related behavior, which in turn were positively associated with problematic smartphone use both for males and females. However, selfi e-related behavior mediated the relationship between narcissism and problematic smartphone use only for females. Conclusions: The study provides fresh insight into our understanding of the psychological mechanisms underlying problematic smartphone use, which may inform prevention and treatment interventions

    Imatinib-mesylate for all patients with hypereosinophilic syndrome?

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    Some recent papers have focused on the activity of imatinib-mesylate, a selective inhibitor of tyrosine kinase, in idiopathic hypereosinophilic syndrome (HES) [1], [2], [3] and [4]. In this setting, a possible therapeutic target was identified by Cools et al. [2], who described the fusion tyrosine-kinase gene FIP1L1/PDGFRA as the result of an interstitial deletion within chromosome 4 in nine out of sixteen (56%) patients affected by HES. Of interest, although in this study the response to imatinib was strictly correlated with the presence of FIP1L1/PDGFRA rearrangement (all patients with such a molecular lesion treated with imatinib responded), only five out of nine responding patients evidenced the abnormal transcript [2]. Among the possible alternative mechanisms for the activation of the PDGFRA tyrosine-kinase domain, these authors suggested there may be a different fusion gene

    Short-range correlations in low-lying nuclear excited states

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    The electromagnetic transitions to various low-lying excited states of 16O, 48Ca and 208Pb are calculated within a model which considers the short-range correlations. In general the effects of the correlations are small and do not explain the required quenching to describe the data.Comment: 6 pages, 2 postscript figures, 1 tabl
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