1,613 research outputs found

    Numerical simulation of long wave runup for breaking and nonbreaking waves

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    Tsunamis produce a wealth of quantitative data that can be used to improve tsunami hazard awareness and to increase the preparedness of the population at risk. These data also allow for a performance evaluation of the coastal infrastructure and observations of sediment transport, erosion, and deposition. The interaction of the tsunami with coastal infrastructures and with the movable sediment bed is a three-dimensional process. Therefore, for runup and inundation prediction, three-dimensional numerical models must be employed. In this study, we have employed Smoothed Particle Hydrodynamics (SPH) to simulate tsunami runup on idealized geometries for the validation and exploration of three-dimensional flow structures in tsunamis. We make use of the canonical experiments for long-wave runup for breaking and nonbreaking waves. The results of our study prove that SPH is able to reproduce the runup of long waves for different initial and geometric conditions. We have also investigated the applicability and the effectiveness of different viscous terms that are available in the SPH literature. Additionally, a new breaking criterion based on numerical experiments is introduced, and its similarities and differences with existing criteria are discussed

    Nontangential limits and Fatou-type theorems on post-critically finite self-similar sets

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    In this paper we study the boundary limit properties of harmonic functions on R+×K\mathbb R_+\times K, the solutions u(t,x)u(t,x) to the Poisson equation 2ut2+Δu=0, \frac{\partial^2 u}{\partial t^2} + \Delta u = 0, where KK is a p.c.f. set and Δ\Delta its Laplacian given by a regular harmonic structure. In particular, we prove the existence of nontangential limits of the corresponding Poisson integrals, and the analogous results of the classical Fatou theorems for bounded and nontangentially bounded harmonic functions.Comment: 22 page

    Developing Intensity-Duration-Frequency (IDF) Curves From Satellite-Based Precipitation: Methodology and Evaluation

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    Given the continuous advancement in the retrieval of precipitation from satellites, it is important to develop methods that incorporate satellite-based precipitation data sets in the design and planning of infrastructure. This is because in many regions around the world, in situ rainfall observations are sparse and have insufficient record length. A handful of studies examined the use of satellite-based precipitation to develop intensity-duration-frequency (IDF) curves; however, they have mostly focused on small spatial domains and relied on combining satellite-based with ground-based precipitation data sets. In this study, we explore this issue by providing a methodological framework with the potential to be applied in ungauged regions. This framework is based on accounting for the characteristics of satellite-based precipitation products, namely, adjustment of bias and transformation of areal to point rainfall. The latter method is based on previous studies on the reverse transformation (point to areal) commonly used to obtain catchment-scale IDF curves. The paper proceeds by applying this framework to develop IDF curves over the contiguous United States (CONUS); the data set used is Precipitation Estimation from Remotely Sensed Information Using Artificial Neural Networks – Climate Data Record (PERSIANN-CDR). IDFs are then evaluated against National Oceanic and Atmospheric Administration (NOAA) Atlas 14 to provide a quantitative estimate of their accuracy. Results show that median errors are in the range of (17–22%), (6–12%), and (3–8%) for one-day, two-day and three-day IDFs, respectively, and return periods in the range (2–100) years. Furthermore, a considerable percentage of satellite-based IDFs lie within the confidence interval of NOAA Atlas 14

    'A greatest hits compilation of mental health support': A qualitative study of health professionals' perspectives of modular CBT in paediatric epilepsy services

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    OBJECTIVES: The primary aim of this qualitative study was to explore the views of health professionals, with little previous clinical mental health training, of an adapted modular cognitive-behavioral intervention (MATCH-ADTC) for common mental health problems in children and young people with epilepsy. METHODS: Healthcare Professionals (HCPs) and their supervisors were interviewed at the start (n = 23) and end (n = 15) of the six-month training period. The interviews were transcribed verbatim and analyzed using thematic analysis. RESULTS: Three higher order themes with sub-themes were identified: (1) strengths of the MATCH-ADTC content and manual; (2) expectations of the treatment; and (3) improving practice with MATCH-ADTC. Overall impressions of the training and treatment were largely positive, with HCPs viewing MATCH-ADTC as an acceptable treatment for the families that they worked with. HCPs highlighted some challenges in delivering an integrated service, particularly relating to the time commitment involved and their own confidence in delivering the intervention, as many participants did not have a mental health background. CONCLUSIONS: The findings suggested that the intervention and training was acceptable to HCPs working in pediatric epilepsy services, and confidence grew over the six-month training period. Further research is needed to understand how to best train, supervise, and support HCPs in pediatric epilepsy services to deliver mental health treatments

    Optimising Evidence-Based Psychological Treatment for the Mental Health Needs of Children with Epilepsy: Principles and Methods

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    There are potent evidence-based psychological treatments for youth with mental health needs, yet they are rarely implemented in clinical practice, especially for youth with mental health disorders in the context of chronic physical illness such as epilepsy. Implementation science, the study of the translation of research into practice, can promote the uptake of existing effective interventions in routine clinical practice and aid the sustainable integration of psychological treatments with routine health care. The aim of this report was to use four implementation science methods to develop a version of an existing effective psychological treatment for mental health disorders [the Modular Approach to Treatment of Children with Anxiety, Depression or Conduct Problems (MATCH-ADTC)] for use within paediatric epilepsy services: (a) literature search; (b) iterative focus groups underpinned by normalisation process theory; (c) Plan-Do-Study-Act methods; and (d) qualitative patient interviews. Findings: Three modifications were deemed necessary to facilitate implementation in children with both mental health disorders and epilepsy. These were (a) a universal brief psychoeducational component addressing the relationship between epilepsy and mental health; (b) supplementary, conditionally activated interventions addressing stigma, parental mental health and the transition to adulthood; and (c) additional training and supervision. The intervention needed relatively little alteration for implementation in paediatric epilepsy services. The modified treatment reflected the scientific literature and the views of clinicians and service users. The multi-method approach used in this report can serve as a model for implementation of evidence-based psychological treatments for children with mental health needs in the context of other chronic illnesses

    Anatomy of a mixed bioclastic–siliciclastic regressive tidal sand ridge: Facies-based case study from the lower Pleistocene Siderno Strait, southern Italy

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    Sand ridges, a common feature of modern open shelves, reflect persistent currents and sediment availability under recent transgressive conditions. They represent the largest bedforms in the oceans and, as such, can yield information on long-term oceanographic processes. However, there is a limited number of tidal sand ridges documented from the rock record, examples of regressive tidal sand ridges are scarce and studies describing ridges in straits are even more rare. This study analyses a Gelasian succession within a structurally controlled, tide-dominated strait in the Siderno Basin, southern Italy. The strait connected two wider basins, and accumulated sediments reworked by amplified tidal (bi-directional) currents. A series of tidal sand ridges with superimposed dunes developed close to the south-eastern end of the strait, where bathymetry was deeper and flow expansion occurred. One of the best-exposed tidal sand ridges, 65 m thick, crops out along a ca 2 km long cliff. Large-scale, ESE-prograding, seaward-offlapping shingles contain sets of bioclastic–siliciclastic, coarse-grained, cross-stratified sandstones, erosionally overlying upper Pliocene shelf marls and fine-grained sandstones. Cross-strata show angular, tangential and sigmoidal foresets with compound architectures and a SSE migration, i.e. oblique to the main growth direction. Fossil content indicates open-marine conditions. The succession changes abruptly across an erosion surface to non-tidal, highly burrowed mixed siliciclastic–bioclastic fine-grained sandstones, less than 15 m thick. Documented features reflect stages of nucleation, active accretion and abandonment of an individual sand ridge, during a complete cycle of relative sea-level change. The ridge formed during a phase of normal regression, with accretion occurring during an initial highstand and the ensuing falling stage. During the lowstand the ridge was split into several minor bodies by enhanced tidal currents. The ensuing transgression draped the moribund ridge with tabular strata, whereas final highstand shelf sedimentation reworked the top of the underlying sand body with weak currents

    Feasibility of telephone-delivered therapy for common mental health difficulties embedded in paediatric epilepsy clinics

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    Background: Mental and physical health treatment should be delivered together for children and young people with epilepsy. Training healthcare professionals (HCPs) in epilepsy services to deliver mental health interventions is an important way to facilitate integrated care. Objective: To determine the feasibility of remotely delivered assessment and psychological treatment for mental health difficulties delivered by HCPs in pediatric epilepsy clinics with limited formal training in psychological interventions. We hypothesized that it would be (i) feasible to train HCPs to deliver the psychological intervention and (ii) that participants receiving the psychological therapy would report reductions in symptoms of mental health difficulties including anxiety, depression, and behavior difficulties and improve quality of life. Methods: Thirty-four children and young people with epilepsy who had impairing symptoms of a common mental health difficulty (anxiety, depression, disruptive behavior, and/or trauma) were allocated to receive 6 months of a modular cognitive behavioral intervention delivered by a HCP with limited formal psychological therapy experience. Thirteen HCPs were trained in delivery of the intervention. Healthcare professional competence was assessed in a two-stage process. Parent-reported measures of mental health symptoms and quality of life were completed at baseline and following the intervention. Paired t-tests were used to analyze changes in symptoms over time. Results: All thirteen HCPs who participated in the training were considered competent in therapeutic delivery by the end of the training period. Twenty-three patients completed pre- and post-intervention measures and were included in the analysis. There were statistically significant improvements in: symptoms of mental health problems (p = 0.01; Cohen’s d = 0.62), total impact of mental health problems (p = 0.03; Cohen’s d = 0.52), anxiety and depression symptoms (p = 0.02; Cohen’s d = 0.57) and quality of life (p = 0.01; Cohen’s d = 0.57). Conclusion: A modular cognitive behavioral treatment delivered over the telephone by HCPs with limited experience of psychological therapy was feasible and effective in treating mental health problems in children and young people with epilepsy. Health-related Quality of Life also improved over the duration of treatment. A randomized controlled trial (RCT) is needed to demonstrate efficacy of the intervention

    Ex situ collections and their potential for the restoration of extinct plants

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    The alarming current and predicted species extinction rates have galvanized conservationists in their efforts to avoid future biodiversity losses but for species extinct in the wild, few options exist. We posed the question, can these be restored, and if so, what role can ex situ plant collections (i.e. botanic gardens, germplasm banks and herbaria) play in the recovery of plant genetic diversity? We reviewed the relevant literature to assess the feasibility of recovering lost plant genetic diversity using ex situ material and the chances of survival of subsequent translocations. Thirteen attempts of recovering species extinct in the wild were found, most of which from material preserved in botanic gardens (12) and seed banks (2). A single case of a locally extirpated population was recovered from herbarium material. Eight (60%) of these cases were successful or partially successful translocations of the focal species or population, while the other five failed or was too early to judge. Our review exposes the many constraints of using ex situ source material for the restoration of plant genetic diversity to the wild, but also highlight the opportunities that modern collecting practices present for plant conservation. Limiting factors are the scarcity of available source material stored ex situ, low viability and reduced longevity of the material, low genetic variation, lack of evolution (especially for material stored in germplasm banks and herbaria) and socio‐economic constraints. However, our review suggests that all types of ex situ collections may effectively contribute to plant species conservation, if their use is informed by a thorough understanding of the aforementioned issues. For these reasons, we conclude that the recovery of plant species currently classed as extinct in the wild is not 100% successful and the possibility to achieve this should not be used as a justification for insufficient in situ conservation efforts

    Structure of an archaeal PCNA1-PCNA2-FEN1 complex: elucidating PCNA subunit and client enzyme specificity.

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    The archaeal/eukaryotic proliferating cell nuclear antigen (PCNA) toroidal clamp interacts with a host of DNA modifying enzymes, providing a stable anchorage and enhancing their respective processivities. Given the broad range of enzymes with which PCNA has been shown to interact, relatively little is known about the mode of assembly of functionally meaningful combinations of enzymes on the PCNA clamp. We have determined the X-ray crystal structure of the Sulfolobus solfataricus PCNA1-PCNA2 heterodimer, bound to a single copy of the flap endonuclease FEN1 at 2.9 A resolution. We demonstrate the specificity of interaction of the PCNA subunits to form the PCNA1-PCNA2-PCNA3 heterotrimer, as well as providing a rationale for the specific interaction of the C-terminal PIP-box motif of FEN1 for the PCNA1 subunit. The structure explains the specificity of the individual archaeal PCNA subunits for selected repair enzyme 'clients', and provides insights into the co-ordinated assembly of sequential enzymatic steps in PCNA-scaffolded DNA repair cascades

    Fragmented in space: the oral history narrative of an Arab Christian from Antioch, Turkey

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    This study uses the case of Can Kılçıksız, an Arab Christian refugee youth from Antioch, Turkey, to argue that globalization may result in fragmented families and subjectivities and can also accelerate processes initiated by modernity and the construction of national identities. Can Kılçıksız and his siblings now live in Turkey, Germany, France and Finland. His life story suggests that males of Arab Christian origin from Antioch who had access to schooling are more likely to be involved in politics whereas females tend to be drawn to evangelical Christian organizations. The case also suggests that sibling ties might prove more durable in the course of transnational migration than conjugal ties. The case of Can Kılçıksız shows that the time/space linked to childhood through memory can play an important role in identity construction of subjects circulating in transnational space
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