241 research outputs found

    Decision-Making Measured by the Iowa Gambling Task in Patients with Alcohol Use Disorders Choosing Harm Reduction versus Relapse Prevention Program

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    AIMS: Two main therapeutic programs were offered to patients suffering from alcohol use disorders (AUDs): avoid the alcohol by abstinence or controlling their consumption. After information and motivational sessions, the patient chooses his own therapeutic plan. However, patients with AUD exhibit poor decision-making. The purpose of this study was to investigate the decision-making in AUD by comparing patients who chose to reduce and control their consumption to those who chose abstinence program. METHODS: Sixty-seven subjects with alcohol use disorder were included (AUD group) for treatment, choosing either a relapse prevention program (RPP) or a harm reduction program (HRP). Patients were compared to a healthy control group (n = 31). Cognitive skills were assessed through the Montreal Cognitive Assessment test, the National Adult Reading Test, the Trail Making Test and the Iowa Gambling Task (IGT). RESULTS: Thirty-seven patients with AUD chose the RPP while 30 followed a HRP. The AUD group performed worse than controls on the IGT. The RPP group had significantly lower performance than both HRP and control groups (these later groups being not statistically different). No correlation was observed between the available clinical, cognitive and intellectual measures. CONCLUSION: This study confirms that the decision-making process of patients with an alcohol use disorder is impaired. However, the 2 groups differ on the IGT scores, despite comparable clinical and cognitive profiles. The patients\u27 decision-making abilities could be a useful guide when developing therapeutic programs

    Aerodynamic analysis models for vertical-axis wind turbines

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    This work details the progress made in the development of aerodynamic models for studying Vertical-Axis Wind Turbines (VAWT’ s) with particular emphasis on the prediction of aerodynamic loads and rotor performance as well as dynamic stall simulations. The paper describes current effort and some important findings using streamtube models, 3-D viscous model, stochastic wind model and numerical simulation of the flow around the turbine blades. Comparison of the analytical results with available experimental data have shown good agreement

    3D URANS analysis of a vertical axis wind turbine in skewed flows

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    The paper demonstrates the potential of an unsteady RANS 3D approach to predict the effects of skewed winds on the performance of an H-type vertical-axis wind turbine (VAWT). The approach is validated through a comparison between numerical and experimental results for a full-scale Darrieus turbine, demonstrating an improved prediction ability of 3D CFD with respect to both 2D CFD and semi-empirical models based on the double multiple stream tubes method. A 3D URANS approach is then adopted to investigate the power increase observed for a straight-bladed small-scale turbine in a wind tunnel when the rotational axis is inclined from 0° to 15° from the vertical. The main advantage of this approach is a more realistic description of complex three-dimensional flow characteristics, such as dynamic stall, and the opportunity to derive local blade flow conditions on any blade portion during upwind and downwind paths. Consequently, in addition to deriving the turbine overall performance in terms of power coefficient, a better insight into the temporal and spatial evolution of the physical mechanisms is obtained. Our principal finding is that the power gain in skewed flows is obtained during the downwind phase of the revolution as the end part of the blade is less disturbed by the wake generated during the upwind phase

    Three-Nucleon Force Effects in Nucleon Induced Deuteron Breakup: Comparison to Data (II)

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    Selected Nd breakup data over a wide energy range are compared to solutions of Faddeev equations based on modern high precision NN interactions alone and adding current three-nucleon force models. Unfortunately currently available data probe phase space regions for the final three nucleon momenta which are rather insensitive to 3NF effects as predicted by current models. Overall there is good to fair agreement between present day theory and experiment but also some cases exist with striking discrepancies. Regions in the phase space are suggested where large 3NF effects can be expected.Comment: 33 pages, 24 ps figures, 9 gif figure

    Tests of electron flavor conservation with the Sudbury Neutrino Observatory

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    We analyze tests of electron flavor conservation that can be performed at the Sudbury Neutrino Observatory (SNO). These tests, which utilize 8^8B solar neutrinos interacting with deuterium, measure: 1) the shape of the recoil electron spectrum in charged-current (CC) interactions (the CC spectrum shape); and 2) the ratio of the number of charged current to neutral current (NC) events (the CC/NC ratio). We determine standard model predictions for the CC spectral shape and for the CC/NC ratio, together with realistic estimates of their errors and the correlations between errors. We consider systematic uncertainties in the standard neutrino spectrum and in the charged-current and neutral current cross-sections, the SNO energy resolution and absolute energy scale, and the SNO detection efficiencies. Assuming that either matter-enhanced or vacuum neutrino oscillations solve the solar neutrino problems, we calculate the confidence levels with which electron flavor non-conservation can be detected using either the CC spectrum shape or the CC/NC ratio, or both. If the SNO detector works as expected, the neutrino oscillation solutions that best-fit the results of the four operating solar neutrino experiments can be distinguished unambiguously from the standard predictions of electron flavor conservation.Comment: 31 pages (RevTeX) + 10 figures (postscript). Requires epsfig.sty. Gzipped figures also available at ftp://ftp.sns.ias.edu/pub/lisi/snopaper . To appear in Phys. Rev.

    Short-term performance variations of different photovoltaic system technologies under the humid subtropical climate of Kanpur in India

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    The study discusses the short-term performance variations of grid-connected photovoltaic (PV) systems installed in Kanpur, India. The analysis presents a holistic view of the performance variations of three PV array technologies [multi-crystalline (multi-Si), copper indium gallium diselenide and amorphous silicon] and two inverter types (high-frequency transformer and low-frequency transformer). The analysis considers the DC–AC conversion efficiency of the inverter, system performance through performance ratio (PR) calculations, energy variations between fixed and tracking systems and the comparison between calculated and simulated data for the examined period. The energy output difference between the tracking and fixed systems of the same PV technology show that these are dependent on differences in temperature coefficient, shading and other system related issues. The PR analysis shows the effect of temperature on the multi-Si system. The difference between the simulated and measured values of the systems was mostly attributed to the irradiance differences. Regarding the inverter evaluation, the results showed that both inverter types underperformed in terms of the conversion efficiency compared with nameplate values

    Effects of the Tucson-Melbourne three-nucleon force in the proton-deuteron breakup process at Ep = 65 MeV

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    We present the calculated cross sections and vector analyzing powers using the Bonn B nucleon-nucleon potential and the Tucson-Melbourne three-nucleon force (3NF) for six collinearity and quasi-free scattering breakup configurations. These calculations are compared to the results of the recent kinematically complete pd experiments at Ep = 65 MeV. The Tucson-Melbourne 3NF, adjusted together with the Bonn B potential to reproduce the triton binding energy, leads to small effects both in cross sections and analyzing powers in all six studied configurations

    Model Analysis of Time Reversal Symmetry Test in the Caltech Fe-57 Gamma-Transition Experiment

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    The CALTECH gamma-transition experiment testing time reversal symmetry via the E2/M1 mulipole mixing ratio of the 122 keV gamma-line in Fe-57 has already been performed in 1977. Extending an earlier analysis in terms of an effective one-body potential, this experiment is now analyzed in terms of effective one boson exchange T-odd P-even nucleon nucleon potentials. Within the model space considered for the Fe-57 nucleus no contribution from isovector rho-type exchange is possible. The bound on the coupling strength phi_A from effective short range axial-vector type exchange induced by the experimental bound on sin(eta) leads to phi_A < 10^{-2}.Comment: 5 pages, RevTex 3.
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