7,034 research outputs found

    The Emotional Reactions to Challenging Behavior Scale-Korean (ERCBS-K): Modification and Validation

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    The purpose of this study was to explore the original version of Mitchell and Hastings\u27s (1998) Emotional Reaction to Challenging Behavior Scale (ERCBS) and estimate validity and reliability of a revised version containing 29 items. The Emotional Reaction to Challenging Behavior Scale-Korean (ERCBS-K) was studied using 445 in-service physical educators (228 females; 217 males). Data were collected using onsite administration as well as mail survey administration procedures. Confirmatory and exploratory factor analyses results supported a five factor, 28-item scale (ERCBS-K). Acceptable internal consistency coefficients were found for each of the subscales of the ERCBS-K (Cronbach\u27s alpha ranged from 0.71 to 0.87)

    Prediction of unsteady blade loads of a wind turbine using RANS and vorticity transport methodologies

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    Numerical simulations of the NREL phase VI wind turbine operating in yawed conditions have been performed using two computational methods; one based on the solution of the Reynolds-averaged Navier-Stokes equations (RANS) using unstructured overset meshes and one known as the Vorticity Transport Model (VTM) that is based on the solution of the vorticity transport equation. The effect of the hub that was present during the NREL experiments was investigated by modeling the hub in the RANS simulations. It was found that the hub influenced the loading significantly at the inboard part of the blade when the blade passed through the wake that was developed by the hub. Both the RANS and VTM codes are able to predict well the unsteady and time-averaged aerodynamic loadings on the wind turbine blades at low wind speeds. At high wind speeds, leading-edge flow separation and strong radial flow are observed on the suction surface of the blades, when the blades are at the retreating side of the rotor. Both the RANS and VTM codes provide less accurate predictions of the blade loads. However, at the advancing side of the rotor, the flow is mostly attached to the surface of the blade, and both the RANS and VTM predictions of the blade loads are in good agreement with the measured data

    Life at the extreme: Lessons from the genome

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    © 2012 BioMed Central Ltd. Extremophile plants thrive in places where most plant species cannot survive. Recent developments in high-throughput technologies and comparative genomics are shedding light on the evolutionary mechanisms leading to their adaptation

    A New Hardware Correlator in Korea: Performance Evaluation using KVN observations

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    We report results of the performance evaluation of a new hardware correlator in Korea, the Daejeon correlator, developed by the Korea Astronomy and Space Science Institute (KASI) and the National Astronomical Observatory of Japan (NAOJ). We conducted Very Long Baseline Interferometry (VLBI) observations at 22~GHz with the Korean VLBI Network (KVN) in Korea and the VLBI Exploration of Radio Astrometry (VERA) in Japan, and correlated the aquired data with the Daejeon correlator. For evaluating the performance of the new hardware correlator, we compared the correlation outputs from the Daejeon correlator for KVN observations with those from a software correlator, the Distributed FX (DiFX). We investigated the correlated flux densities and brightness distributions of extragalactic compact radio sources. The comparison of the two correlator outputs show that they are consistent with each other within <8%<8\%, which is comparable with the amplitude calibration uncertainties of KVN observations at 22~GHz. We also found that the 8\% difference in flux density is caused mainly by (a) the difference in the way of fringe phase tracking between the DiFX software correlator and the Daejeon hardware correlator, and (b) an unusual pattern (a double-layer pattern) of the amplitude correlation output from the Daejeon correlator. The visibility amplitude loss by the double-layer pattern is as small as 3\%. We conclude that the new hardware correlator produces reasonable correlation outputs for continuum observations, which are consistent with the outputs from the DiFX software correlator.Comment: 13 pagee, 9 figures, 3 tables, to appear in JKAS (received February 9, 2015; accepted March 16, 2015

    4C-seq characterization of Drosophila BEAF binding regions provides evidence for highly variable long-distance interactions between active chromatin

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    © 2018 Shrestha et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Chromatin organization is crucial for nuclear functions such as gene regulation, DNA replication and DNA repair. Insulator binding proteins, such as the Drosophila Boundary Element-Associated Factor (BEAF), are involved in chromatin organization. To further understand the role of BEAF, we detected cis-and trans-interaction partners of four BEAF binding regions (viewpoints) using 4C (circular chromosome conformation capture) and analyzed their association with different genomic features. Previous genome-wide mapping found that BEAF usually binds near transcription start sites, often of housekeeping genes, so our viewpoints were selected to reflect this. Our 4C data show the interaction partners of our viewpoints are highly variable and generally enriched for active chromatin marks. The most consistent association was with housekeeping genes, a feature in common with our viewpoints. Fluorescence in situ hybridization indicated that the long-distance interactions occur even in the absence of BEAF. These data are most consistent with a model in which BEAF is redundant with other factors found at active promoters. Our results point to principles of long-distance interactions made by active chromatin, supporting a previously proposed model in which condensed chromatin is sticky and associates into topologically associating domains (TADs) separated by active chromatin. We propose that the highly variable long-distance interactions we detect are driven by redundant factors that open chromatin to promote transcription, combined with active chromatin filling spaces between TADs while packing of TADs relative to each other varies from cell to cell

    Electrolyte Effects on Spinel Dissolution and Cathodic Capacity Losses in 4 V U/LiJvIn2O4 Rechargeable Cells

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    Spinel dissolution and cathodic capacity losses in 4 V Li/LiMn204 secondary cells were examined in various electrolyte solutions comprising different solvents and Li salts. It was found that spinel dissolution is induced by acids that are generated as a result of electrochemical oxidation of solvent molecules on composite cathodes. Among various organic solvents, ethers such as tetrahydrofuran and dimethoxyethane were readily oxidized to produce acids whereas carbonates (ethylene carbonate, propylene carbonate, diethylcarbonate) were relatively inert. Consequently, when a spinelloaded composite cathode was charge/discharge cycled in the potential range of 3.6 to 4.3 V (vs. Li/Li), both the acid concentration and the extent of spinel dissolution was much higher in the ether-containing electrolytes as compared to the carbonates. The results, obtained from the chemical analysis on acid-attacked spinel powders and from the open-circuit potential measurement of composite cathodes, indicated that Li and Mn ion extraction is dominant in the earlier stage of acid attack. As the spinel dissolution further continues, however, oxygen losses from the lattice become more important. The combined feature of solvent oxidation and spinel dissolution was also affected by the nature of lithium salts added. Generally, the solvent-derived acid generation was not significant in those electrolytes containing fluorinated salts (LiPF5, LiBF4, and LiA5F6), yet the spinel dissolution in these electrolytes was still appreciable because acids were generated via another pathway; a reaction between the F-containing anions and impurity water.This work has been supported by the Korean Science and Engineering Foundation through the Research Center for Thin Film Fabrication and Crystal Growing of Advanced Materials in Seoul National Universit

    Compromised RNA polymerase III complex assembly leads to local alterations of intergenic RNA polymerase II transcription in Saccharomyces cerevisiae

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    © 2014 Wang et al. Background: Assembled RNA polymerase III (Pol III) complexes exert local effects on chromatin processes, including influencing transcription of neighboring RNA polymerase II (Pol II) transcribed genes. These properties have been designated as \u27extra-transcriptional\u27 effects of the Pol III complex. Previous coding sequence microarray studies using Pol III factor mutants to determine global effects of Pol III complex assembly on Pol II promoter activity revealed only modest effects that did not correlate with the proximity of Pol III complex binding sites. Results: Given our recent results demonstrating that tDNAs block progression of intergenic Pol II transcription, we hypothesized that extra-transcriptional effects within intergenic regions were not identified in the microarray study. To reconsider global impacts of Pol III complex binding, we used RNA sequencing to compare transcriptomes of wild type versus Pol III transcription factor TFIIIC depleted mutants. The results reveal altered intergenic Pol II transcription near TFIIIC binding sites in the mutant strains, where we observe readthrough of upstream transcripts that normally terminate near these sites, 5\u27- and 3\u27-extended transcripts, and de-repression of adjacent genes and intergenic regions. Conclusions: The results suggest that effects of assembled Pol III complexes on transcription of neighboring Pol II promoters are of greater magnitude than previously appreciated, that such effects influence expression of adjacent genes at transcriptional start site and translational levels, and may explain a function of the conserved ETC sites in yeast. The results may also be relevant to synthetic biology efforts to design a minimal yeast genome

    Quantum contextuality for a relativistic spin-1/2 particle

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    The quantum predictions for a single nonrelativistic spin-1/2 particle can be reproduced by noncontextual hidden variables. Here we show that quantum contextuality for a relativistic electron moving in a Coulomb potential naturally emerges if relativistic effects are taken into account. The contextuality can be identified through the violation of noncontextuality inequalities. We also discuss quantum contextuality for the free Dirac electron as well as the relativistic Dirac oscillator.Comment: REVTeX4, 5 page
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