75 research outputs found

    The empirical basis for modelling glacial erosion rates

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    Glaciers are highly effective agents of erosion that have profoundly shaped Earth’s surface, but there is uncertainty about how glacial erosion should be parameterised in landscape evolution models. Glacial erosion rate is usually modelled as a function of glacier sliding velocity, but the empirical basis for this relationship is weak. In turn, climate is assumed to control sliding velocity and hence erosion, but this too lacks empirical scrutiny. Here, we present statistically robust relationships between erosion rates, sliding velocities, and climate from a global compilation of 38 glaciers. We show that sliding is positively and significantly correlated with erosion, and derive a relationship for use in erosion models. Our dataset further demonstrates that the most rapid erosion is achieved at temperate glaciers with high mean annual precipitation, which serve to promote rapid sliding. Precipitation has received little attention in glacial erosion studies, but our data illustrate its importance

    Eclectic approach to anxiety disorders among rural children Abordagem ecletica a transtornos de ansiedade em criancas de zona rural

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    Introduction: Anxiety disorders in primary school-aged children negatively affect their mental health and psychological development. Available non-medical treatments for these conditions are time-consuming and expensive. In this context, eclectic therapy is a therapeutic approach that incorporates some therapeutic techniques and philosophies to create the ideal treatment. In this study, eclectic therapy consisted of art therapy and cognitive-behavioral therapy designed for children suffering from high level of anxiety in their middle childhood years. The therapy also included group guidance sessions for their mothers. The effectiveness of this intervention was examined in the study. Methods: 61 students aged 9-12 years with high levels of anxiety participated in the study. Intervention A (n = 20) consisted of 9-hour eclectic therapy for children with 3-hour group guidance sessions for their mothers. Intervention B (n = 20) consisted of 9-hour eclectic therapy for children. There was also a control group (n = 21). Results: Teacher ratings of children’s mental health difficulties and self-report ratings of anxiety disorders indicated a significant difference from pretest to posttest, revealing a large effect size between the two interventions. Higher levels of pretest scores significantly predicted higher posttest scores for all domains of anxiety and mental health difficulties. Furthermore, age, gender, mothers working a 15-hour day, mother’s educational level, parental divorce rates, parental death, and family monthly income predicted therapy outcomes. Conclusion: Results provide support for the effectiveness of eclectic art and CBT to improve children’s mental health and reduce anxiety through changing thoughts, beliefs, emotions, and behaviors that may cause fear and anxiety

    Lawson criterion for ignition exceeded in an inertial fusion experiment

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    For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

    Disease: A Hitherto Unexplored Constraint on the Spread of Dogs (Canis lupus familiaris) in Pre-Columbian South America

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    Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE) Conceptual Design Report Volume 1: The LBNF and DUNE Projects

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    This document presents the Conceptual Design Report (CDR) put forward by an international neutrino community to pursue the Deep Underground Neutrino Experiment at the Long-Baseline Neutrino Facility (LBNF/DUNE), a groundbreaking science experiment for long-baseline neutrino oscillation studies and for neutrino astrophysics and nucleon decay searches. The DUNE far detector will be a very large modular liquid argon time-projection chamber (LArTPC) located deep underground, coupled to the LBNF multi-megawatt wide-band neutrino beam. DUNE will also have a high-resolution and high-precision near detector

    The Single-Phase ProtoDUNE Technical Design Report

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    ProtoDUNE-SP is the single-phase DUNE Far Detector prototype that is under construction and will be operated at the CERN Neutrino Platform (NP) starting in 2018. ProtoDUNE-SP, a crucial part of the DUNE effort towards the construction of the first DUNE 10-kt fiducial mass far detector module (17 kt total LAr mass), is a significant experiment in its own right. With a total liquid argon (LAr) mass of 0.77 kt, it represents the largest monolithic single-phase LArTPC detector to be built to date. It's technical design is given in this report
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