bluuebunny/crossref_metadata_2025_split huggingface dataset:
Progress with the COGENT Edge Kinetic Code: Implementing the Fokker‐Planck Collision Operator
Authors: Dorf M. A. , Cohen R. H. , Dorr M. , Hittinger J. , Rognlien T. D. 
Published: June 2014

AbstractCOGENT is a continuum gyrokinetic code for edge plasma simulations being developed by the Edge Simulation Laboratory collaboration. The code is distinguished by application of a fourth‐order finite‐volume (conservative) discretization, and mapped multiblock grid technology to handle the geometric complexity of the tokamak edge. The distribution function F is discretized in v‖ – μ (parallel velocity – magnetic moment) velocity coordinates, and the code presently solves an axisymmetric full‐f gyro‐kinetic equation coupled to the long‐wavelength limit of the gyro‐Poisson equation. COGENT capabilities are extended by implementing the fully nonlinear Fokker‐Plank operator to model Coulomb collisions in magnetized edge plasmas. The corresponding Rosenbluth potentials are computed by making use of a finite‐difference scheme and multipole‐expansion boundary conditions. Details of the numerical algorithms and results of the initial verification studies are discussed. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Density Regimes and Heat Flux Deposition in the WEST Shallow Divertor Configuration
Authors: Bufferand H. , Bucalossi J. , Ciraolo G. , Fedorczak N. , Ghendrih P. , Leybros R. , Marandet Y. , Serre E. , Tamain P. 
Published: June 2014

AbstractTo support ITER divertor design, the WEST project on Tore Supra aims at studying high heat fluxes on tungsten monoblock during long pulses. In that persective, a particular attention is paid to simulate the edge plasma interaction with complex PFCs using the transport code SOLEDGE2D‐EIRENE. The plasma response to a heating and puffing scenario is described as well as the so‐called divertor density regimes, characterizing the operational domain of the WEST divertor. These results are compared for two different magnetic configurations: a semi‐open double null divertor with the X‐point away from the target plates and a shallow divertor configuration with the X‐point close to the targets. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Systematic Study of Tungsten Impurity Transport in Representative Regimes of Divertor Plasma
Authors: Yamoto S. , Hoshino K. , Toma M. , Homma Y. , Hatayama A. , Bonnin X. , Coster D. , Schneider R. 
Published: June 2014

AbstractThe tungsten impurity transport has been studied by IMPGYRO code for a model tokamak geometry of JT‐60U tungsten experiments. The background plasma profiles calculated from SOLPS has been used. The density profiles of tungsten are compared between the low background deuterium density (Case A: n = 2.0 × 1019 m–3 at core side boundary) and the high background deuterium density (Case B: n = 3.0 × 1019 m–3 at core side boundary). In both cases, flow reversal in the SOL has been observed. The impurity density profile in the SOL is more localized for Case B. These features are possibly explained by the force balance between the thermal force and the friction force. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modeling of Hydrogen Retention and Outgassing from Co‐Deposits with Distributed Energy States
Authors: Smirnov R. D. , Krasheninnikov S. I. , Guterl J. , Baldwin M. J. , Doerner R. P. 
Published: June 2014

AbstractA hydrogen retention/outgassing model with distributed hydrogen energy states in material is proposed. The model considers hydrogen in co‐deposits to occupy continuous energy states arising from all realizable local atomic arrangements in a medium with some degree of disorder. The outgassing flux of hydrogen from a sample is described via occupancy evolution of energy states corresponding to free hydrogen. We apply the model to analysis of hydrogen thermo‐desorption experiments on beryllium co‐deposits produced in a Be capable sputter magnetron system at the UCSD PISCES laboratory. It is demonstrated that the model can describe experimentally obtained time evolutions of hydrogen desorption flux from co‐deposits in different thermal outgassing regimes. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simulation of Radiation Cooling Effects in the GAMMA 10 West End‐Cell Using Fluid Model
Authors: Takeda H. , Nakashima Y. , Iida Y. , Hosoi K. , Furuta T. , Toma M. , Hatayama A. , Ichimura K. , Ueda H. , Iwamoto M. , Hosoda Y. , Yoshikawa M. , Sakamoto M. , Ichimura M. , Imai T. 
Published: June 2014

AbstractWe have started a simulation study of background plasma in the GAMMA 10 west end‐cell using fluid‐code in order to understand divertor simulation experiment. This fluid code is B2 code without including the effects of drifts and currents. In this paper, we obtained the effects of additional neutral particles density. As increasing amount of additional neutral particle density, ion and electron temperature decrease and plasma density builds up. Especially, the peak of plasma density moves from z = 10.04 m from z = 10.1 m. However, electron temperature does not decrease detachment front for high ion temperature. Therefore, it needs that ion temperature is decreased. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Simple and Fast Poisson Solver with Arbitrary Boundary Shape and Condition for PIC Simulation
Authors: Takizuka T. , Azuma S. , Fukuyama A. , Shimizu K. 
Published: June 2014

AbstractParticle‐in‐cell (PIC) simulations are the very powerful method to understand physics of edge plasmas in fusion devices. Poisson solver with a regular grid in a rectangular vessel is very fast, but it cannot simply be applicable to simulations in complicated divertor configuration. In this paper, a simple and fast Poisson solver with arbitrary boundary shape and condition for PIC simulation is proposed. Boundary points are essential for this Poisson solver, on which the charge density is appropriately given and the boundary condition is satisfied. For particle simulations in the open system, it is necessary to distinguish whether a traced particle moves freely or hits the wall boundary during a time step. A new method for PIC simulation to discriminate a particle position before the boundary or beyond the boundary is also presented. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Guiding Center Orbit Following Calculation of Edge Particle and Heat Transport in Stochastic Magnetic Field
Authors: Chang C.C. , Nishimura Y. , Cheng C.Z. 
Published: June 2014

AbstractParticle and heat transport in tokamak edge is investigated by guiding center orbit following calculation. The guiding center equation is solved for both electrons and ions in the presence of magnetic perturbation. It is suggested that the remnants of the magnetic islands play a role in characterizing the radial transport. The transport coefficient is estimated which also demonstrate local structure in the vicinity of magnetic islands. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Impact of Differing Electron and Ion Temperatures on Emission Lines of Impurities in Tokamak Divertors
Authors: Koubiti M. , Godbert‐Mouret L. , Ferri S. , Marandet Y. , Rosato J. , Stamm R. 
Published: June 2014

AbstractIn this paper we present some investigations of the broadening mechanisms affecting the emission line profiles of impurities present in the divertor regions of tokamaks. For that purpose, we have considered two visible lines (C IV n = 5‐6 and n = 6‐7) emitted by lithium‐like carbon ions for which the contributions of the Zeeman, Stark and Doppler effects are examined. The paper is focused on the impact of differing electron and ion temperatures on the broadening and shapes of the C IV n = 6‐7 line for conditions relevant to a detached tokamak divertor plasma. It is shown, that the C IV n = 6‐7 line profile calculated with differing electron and ion temperatures may be significantly different from the one calculated with equal temperatures but the same density. This suggests that the electron density determination from the fit of the measured spectra of such a line may be inaccurate when using equal ion and electron temperatures instead of differing ones. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the Electron Distribution Function in the Edge Plasma
Authors: Gasteiger M. , Tskhakaya D. 
Published: June 2014

AbstractIn this work we consider the electron kinetic equation and obtain electron velocity distributions and corresponding moments. This model represents a generalization of Chodura's [1] by inclusion of electron‐electron and electron inelastic collisions. We find out that ee collisions in the edge plasma reduce the heat flux significantly and cannot be neglected. Contrary to this relatively weak inelastic collisions do not affect the electron heat flux. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Self‐Consistent COREDIV Modelling of WEST Plasma Scenarios
Authors: Marandet Y. , Ivanova‐Stanik I. , Zagörski R. , Bourdelle C. , Bucalossi J. , Bufferand H. , Ciraolo G. , Tsitrone E. 
Published: June 2014

AbstractThe importance of core‐edge coupling in the WEST tokamak via tungsten production and core radiation is investigated with the COREDIV code. We first focus on the idealized situation where the plasma is free of light impurities, and show that for achievable high density discharges tungsten production can be essentially extinguished. For lower densities, core edge coupling is strong, that is tungsten plays a major role in regulating the power flowing through the Scrape‐off layer. The latter is found to saturate with increasing heating power due to increasing radiation losses in the core. Then we investigate the extent to which light impurities change this picture by performing a scan in boron concentration, since Ion Cyclotron Resonance Heating antenna protections may be boron coated. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multi‐Fluid Transport Modeling of NSTX Upgrade Standard and Snowflake Divertor Configurations
Authors: Meier E. T. , Soukhanovskii V. A. , Gerhardt S. , Menard J. E. , Rognlien T. D. 
Published: June 2014

AbstractIn NSTX Upgrade (NSTX‐U), power exhaust is expected to challenge available material and heat removal technologies, which are limited to ∼10 MW/m2. Preliminary analysis of heat flux mitigation strategies, including the snowflake divertor configuration and radiative divertor operation, is performed with the multi‐fluid edge transport code, UEDGE. Divertor recycling between 95% and 99%, and power exhaust between 7 and 9 MW are explored. Compared to the standard divertor, the particular snowflake divertor studied here strongly reduces outer target heat flux, but tends to have higher (>10 MW/m2) inner target heat flux. This suggests that snowflake divertor optimization should be pursued in future work. Both neon and argon impurity seeding scenarios mitigate high heat fluxes in both standard and snowflake configurations, but argon can cause radiative collapse of the core plasma at only 3% concentration. Divertor cryopumping is also considered, and modeling shows ∼50% more particle removal with the snowflake divertor. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modeling of Tungsten Dust Transport in ITER with Multi‐Physics Code DUSTT/UEDGE
Authors: Pigarov A. Yu. , Smirnov R. D. , Krasheninnikov S. I. , Rognlien T. D. 
Published: June 2014

AbstractSelf‐consistent modeling of dust particle kinetics and multi‐fluid multi‐species transport of boundary plasmas in ITER is performed with the multi‐physics code DUSTT/UEDGE. Results are presented for the sensitivity of the pedestal and divertor plasmas to the injection rate, size, and source location of the dust particles. The cases of low‐z and high‐z dust material injection are compared. The impact of dust ablation on impurity inventory, distribution of ions over ionization states, and electron plasma power losses is studied. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Evaluation of acridine orange, LysoTracker Red, and quinacrine as fluorescent probes for long‐term tracking of acidic vesicles
Authors: Pierzyńska‐Mach Agnieszka , Janowski Paweł A. , Dobrucki Jurek W. 
Published: June 2014

AbstractAcidic vesicles can be imaged and tracked in live cells after staining with several low molecular weight fluorescent probes, or with fluorescently labeled proteins. Three fluorescent dyes, acridine orange, LysoTracker Red DND‐99, and quinacrine, were evaluated as acidic vesicle tracers for confocal fluorescence imaging and quantitative analysis. The stability of fluorescent signals, achievable image contrast, and phototoxicity were taken into consideration. The three tested tracers exhibit different advantages and pose different problems in imaging experiments. Acridine orange makes it possible to distinguish acidic vesicles with different internal pH but is fairly phototoxic and can cause spectacular bursts of the dye‐loaded vesicles. LysoTracker Red is less phototoxic but its rapid photobleaching limits the range of useful applications considerably. We demonstrate that quinacrine is most suitable for long‐term imaging when a high number of frames is required. This capacity made it possible to trace acidic vesicles for several hours, during a process of drug‐induced apoptosis. An ability to record the behavior of acidic vesicles over such long periods opens a possibility to study processes like autophagy or long‐term effects of drugs on endocytosis and exocytosis. © 2014 International Society for Advancement of Cytometry
Application of flow cytometry for genome size determination in Geosmithia fungi: A comparison of methods
Authors: Veselská Tereza , Svoboda Jan , Růžičková Žaneta , Kolařík Miroslav 
Published: June 2014

AbstractGenome size has played an important role in the evolution of plants and animals because changes in genome size seem to accompany if not facilitate evolutionary adaptation to environmental conditions. Flow cytometry (FCM) is a widespread method for determining genome size thanks to its high accuracy and speed of measurements. Nevertheless, only a few comparative studies of FCM methods exist in the field of mycology, and reviews are absent. In this study, we compared the suitability of several concentrations and RNAse A incubation times, fixatives and buffers for estimating genome size in fungi. We chose the genus Geosmithia as a model filamentous fungus. We also introduced a new standard, Aspergillus fumigatus CEA10, to determine absolute genome size. We found FCM to be an appropriate method for measuring genome size in fungi, but optimization steps showed that incorrect propidium iodide staining of nuclei can overestimate genome size due to cytoplasmic staining. We identified fixation with methanol:glacial acetic acid (3:1 v/v), 10% DMSO, 0.1% Triton‐X 100, and 5 mM EDTA in combination with Tris‐MgCl2 buffer as the best treatment. © 2014 International Society for Advancement of Cytometry
Microfluidic‐based, live‐cell analysis allows assessment of NK‐cell migration in response to crosstalk with dendritic cells
Authors: Mahmood Sajid , Nandagopal Saravanan , Sow Ibrahim , Lin Francis , Kung Sam K. P. 
Published: June 2014

Migration and localization of NK cells into peripheral tissues are tightly regulated under normal and pathological conditions. The physiological importance of NK cell–DC crosstalk has been well documented. However, the ways in which DCs regulate the migratory properties of NK cells (such as chemotaxis, chemokinesis, chemo‐repulsion) are not fully defined in vitro. Here, we employed a microfluidic platform to examine, at the single‐cell level, C57BL/6 NK‐cell migrations in a stable chemical gradient. We observed that soluble factors released by the immature and LPS‐activated mature DCs induced a high level of chemotactic movement of IL‐2‐activated NK cells in vitro. We confirmed these findings in a standard trans‐well migration assay, and identified CXCR3 as a key receptor on the NK cells that mediated the migration. More interestingly, we revealed a novel function of granulocyte macrophage colony‐stimulating factor in repulsing NK‐cell migrations. The future uses of such microfluidic device in the systematic evaluations of NK‐cell migratory responses in NK cell–DC crosstalk will provide new insights into the development of DC‐based NK‐cell therapies against tumor and infections.
Evaluation of Some Redox Mediators in the Design of Reagentless Amperometric Glucose Biosensor
Authors: Kausaite‐Minkstimiene Asta , Mazeiko Viktor , Ramanaviciene Almira , Oztekin Yasemin , Osman Solak Ali , Ramanavicius Arunas 
Published: June 2014

AbstractThe influence of redox mediators (tetrathiafulvalene (TTF), tetrathiafulvalene‐tetracyanoquinodimethane complex (TTF‐TCNQ), phenazine methosulfate (PMS), 5,6‐diamino‐1,10‐phenonthroline (5,6‐DAP), potassium ferrocyanide (K4[Fe(CN)6]), methylene blue (MB) and toluidine blue (TB)) on the response of amperometric glucose biosensor was investigated in this research. Graphite rod electrode (GRE) modified by adsorbed mediator and glucose oxidase (GOx) cross‐linked with glutaraldehyde was served as working electrode. The highest amperometric signals were observed by using TTF and TTF‐TCNQ as mediators. The impact of amount of immobilized GOx, an optimal pH region for operation, stability and reproducibility of the analytic signal of designed biosensor using these mediators were investigated and discussed.
A Selective Immunosensor for D‐dimer Based on Antibody Immobilized on a Graphene Electrode with Incorporated Lipid Films
Authors: Nikoleli Georgia‐Paraskevi , Nikolelis Dimitrios P. , Tzamtzis Nikolaos , Psaroudakis Nikolas 
Published: June 2014

AbstractThe present article describes a miniaturized potentiometric D‐dimer biosensor on graphene nanosheets with incorporated lipid films. The graphene electrode was used for the development of a very selective and sensitive immunosensor for the detection of D‐dimer by immobilizing the mouse anti human D‐dimer antibody on stabilized lipid films. The immunosensor responded for the wide range of D‐dimer concentrations with fast response time of ca. 15 s. The presented potentiometric D‐dimer biosensor is easy to construct and exhibits good reproducibility, reusability, selectivity, rapid response times, long shelf life and high sensitivity of ca. 59 mV/decade over the D‐dimer logarithmic concentration range from 10−6 μg/L to 10−3 μg/L.
Blade root moment sensor failure detection based on multibeam LIDAR for fault‐tolerant individual pitch control of wind turbines
Authors: Stotsky Alexander 
Published: June 2014

AbstractDetection of blade root moment sensor failures is an important problem for fault‐tolerant individual pitch control, which plays a key role in reduction of uneven blade loads of large wind turbines. A new method for detection of blade root moment sensor failures which is based on variations induced by a vertical wind shear is described in this paper. The detection is associated with monitoring of statistical properties of the difference between amplitudes of the first harmonic of the blade load, which is calculated in two different ways. The first method is based on processing of the load sensor signal, which contains a number of harmonics. The first harmonic is recovered via least squares estimation of the blade load signal with harmonic regressor and strictly diagonally dominant (SDD) information matrix. The second method is a model‐based method of estimation of the first harmonic, which relies on the blade load model and upwind speed measurements provided by multibeam Light Detection and Ranging (LIDAR). This is a new application for future LIDAR‐enabled wind turbine technologies. Moreover, adaptation of the load model in a uniform wind field is proposed. This adaptation improves accuracy of the load estimation and hence the performance of the blade load sensor failure detection method.
Ultra‐High‐Frequency Algorithmic Arbitrage Across International Index Futures
Authors: Alsayed Hamad , McGroarty Frank 
Published: June 2014

ABSTRACTWe show that persistent lead–lag relationships spanning mere fractions of a second exist in all three possible pairings of the S&P 500, FTSE 100 and DAX futures contracts. These relationships exhibit clear intraday patterns which help us to forecast mid‐quote changes in lagging contracts with directional accuracy in excess of 85%. A simple algorithmic trading strategy exploiting these relations yields economically significant profits which are robust to market impact costs and the bid–ask spread. We find that price slippage and infrastructure costs are our most important limits to arbitrage. Our results support the impossibility of EMH view that informational inefficiencies incentivize arbitrageurs to eliminate mispricings. Copyright © 2014 John Wiley & Sons, Ltd.
NERC and Enforcement Issues: Self‐Reporting Routine Compliance Violations
Authors: Carpentier Deborah 
Published: June 2014

AbstractThe Federal Energy Regulatory Commission (FERC) assessed a $750,000 civil penalty against International Transmission Company and several of its public utility affiliates for failure to obtain FERC approval under Section 203 of the Federal Power Act (FPA) for 20 jurisdictional transactions, which were self‐reported to FERC. The company and its affiliates were also penalized here for failing to make appropriate filings under FPA Section 205 with respect to 174 jurisdictional agreements that were not self‐reported to FERC.
Differential prefrontal and subcortical circuitry engagement during encoding of semantically related words in patients with late‐life depression
Authors: Weisenbach Sara L. , Kassel Michelle T. , Rao Julia , Weldon Annie L. , Avery Erich T. , Briceno Emily M. , Ajilore Olusola , Mann Megan , Kales Helen C. , Welsh Robert C. , Zubieta Jon‐Kar , Langenecker Scott A. 
Published: June 2014

ObjectiveVerbal memory difficulties are common among individuals with late‐life depression (LLD), though there is limited knowledge about disruptions to underlying cerebral circuitry. The purpose of this study is to examine aberrations to cerebral networks implicated in encoding novel verbal semantic material among older adults with LLD.MethodsTwenty‐four older adults with early‐onset LLD and 23 non‐depressed comparisons participated in the study. Participants completed a word list‐learning task while undergoing functional magnetic resonance imaging.ResultsIn the context of equivalent recall and recognition of words following scanning and similar hippocampal volumes, patients with LLD exhibited less activation in structures known to be relevant for new learning and memory, including hippocampus, parahippocampal gyrus, insula, and cingulate, relative to non‐ill comparisons. An important region in which the LLD group displayed greater activation than the non‐depressed comparison group was in left inferior frontal gyrus, an area involved in cognitive control and controlled semantic/phonological retrieval and analysis; this region may be critical for LLD patients to consolidate encoded words into memory.ConclusionsFunctional irregularities found in LLD patients may reflect different modes of processing to‐be‐remembered information and/or early changes predictive of incipient cognitive decline. Future studies might consider mechanisms that could contribute to these functional differences, including hypothalamic‐pituitary‐adrenal axis functioning and vascular integrity, and utilize longitudinal designs in order to understand whether functional changes are predictive of incipient cognitive decline. Copyright © 2014 John Wiley & Sons, Ltd.