Sensory prediction errors, not performance errors, update memories in visuomotor adaptation

Sensory prediction errors are thought to update memories in motor adaptation, but the role of performance errors is largely unknown. To dissociate these errors, we manipulated visual feedback during fast shooting movements under visuomotor rotation. Participants were instructed to strategically correct for performance errors by shooting to a neighboring target in one of four conditions: following the movement onset, the main target, the neighboring target, both targets, or none of the targets disappeared. Participants in all conditions experienced a drift away from the main target following the strategy. In conditions where the main target was shown, participants often tried to minimize performance errors caused by the drift by generating corrective movements. However, despite differences in performance during adaptation between conditions, memory decay in a delayed washout block was indistinguishable between conditions. Our results thus suggest that, in visuomotor adaptation, sensory predictions errors, but not performance errors, update the slow, temporally stable, component of motor memory

Computational model of visual attention : integrative approach

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Tuning the Activity of Electrochemical Ozone Production by Heterojunction Architecture

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Degradation of ranitidine and changes in N-nitrosodimethylamine formation potential by advanced oxidation processes: Role of oxidant speciation and water matrix

This study investigated the effects of thirteen (photo/electro) chemical oxidation processes on the formation potential (FP) of N-nitrosodimethylamine (NDMA) during the chloramination of ranitidine in reverse osmosis (RO) permeate and brine. The NDMA-FP varied significantly depending on the pretreatment process, initial pH, and water matrix types. At higher initial pH values (> 7.0), most pretreatments did not reduce the NDMA-FP, presumably because few radical species and more chloramine-reactive byproducts were generated. At pH < 7.0, however, electrochemical oxidation assisted by chloride and Fe2+/H2O2, catalytic wet peroxide oxidation and peroxydisulfate-induced pretreatments removed up to 85% of NDMA-FP in the RO brine. Ultraviolet (UV) irradiation or prechlorination alone did not reduce the NDMA-FP effectively, but combined UV/chlorine treatment effectively reduced the NDMA-FP. In contrast, after UV irradiation (2.1 mW cm(-2) for 0.5 h) in the presence of H2O2 and chloramine, NDMA formation increased substantially (up to 26%) during the post-chloramination of the RO permeate. Mass spectrometric analysis and structural elucidation of the oxidation byproducts indicated that compared with the reactive nitrogen species generated by UV/NH2Cl, sulfate radicals and (photo/electro) chemically generated reactive chlorine species were more promising for minimizing NDMA-FP. Unlike, the hemolytic center dot OH driven by UV/H2O2, the center dot OH from Fe(IV)-assisted pretreatments showed a significant synergistic effect on NDMA-FP reduction. Overall, the results suggest the need for a careful assessment of the type of radical species to be used for treating an RO water system containing amine-functionalized compounds.11Nsciescopu

High chlorine evolution performance of electrochemically reduced TiO2 nanotube array coated with a thin RuO2 layer by the self-synthetic method

Recently, reduced TiO2 nanotube arrays via electrochemical self-doping (r-TiO2) are emerging as a good alternative to conventional dimensionally stable anodes (DSAs) due to their comparable performance and low-cost. However, compared with conventional DSAs, they suffer from poor stability, low current efficiency, and high energy consumption. Therefore, this study aims to advance the electrochemical performances in the chlorine evolution of r-TiO2 with a thin RuO2 layer coating on the nanotube structure (RuO2@r-TiO2). The RuO2 thin layer was successfully coated on the surface of r-TiO2. This was accomplished with a self-synthesized layer of ruthenium precursor originating from a spontaneous redox reaction between Ti3+ and metal ions on the r-TiO2 surface and thermal treatment. The thickness of the thin RuO2 layer was approximately 30 nm on the nanotube surface of RuO2@r-TiO2 without severe pore blocking. In chlorine production, RuO2@r-TiO2 exhibited higher current efficiency (similar to 81.0%) and lower energy consumption (similar to 3.0 W h g(-1)) than the r-TiO2 (current efficiency of similar to 64.7% of and energy consumption of similar to 5.2 W h g(-1)). In addition, the stability (ca. 22 h) was around 20-fold enhancement in RuO2@r-TiO2 compared with r-TiO2 (ca. 1.2 h). The results suggest a new route to provide a thin layer coating on r-TiO2 and to synthesize a high performance oxidant-generating anode.11Nsciescopu

Effects of Anode Materials and Chloride Ions on Current Efficiency of Electrochemical Oxidation of Carbohydrate Compounds

This study interrogated IrO2, RuO2, IrRuO2, Pt, and boron doped diamond for electrochemical oxidation of alginic acid and glucose. Linear sweep voltammetry estimated onset potential of oxygen evolution reaction from 1.03 to 2.60 V NHE in an inverse relation with the current efficiency of free chlorine generation in NaCl solutions, while further oxidation of free chlorine (chlorate ion generation) underestimated the current efficiency on Pt and boron doped diamond. Electrochemical oxidation experiments at 50 mA cm(-2) confirmed the free chlorine to be the primary oxidant for chemical oxygen demand degradation on the dimensionally stable anodes since the current efficiency of free chlorine generation (25-35%) was comparable with the current efficiency of chemical oxygen demand degradation. The ClO3- generation on Pt was retarded in alginic acid degradation, but effective during glucose degradation due to different reactivity with free chlorine. For boron doped diamond, direct and center dot OH mediated oxidation were significant (11% for alginic acid and 22% for glucose) and competition among organic pollutants, Cl-, and free chlorine for center dot OH determined the current efficiency of organic compounds degradation. In a saline water, IrO2 anode was the most energy-efficient (specific energy consumption for alginic acid: 48 Wh gCOD(-1)) with minimal formation of ClO3-. (C) 2019 The Electrochemical Society.11Nsciescopu

An enhanced selectivity for chlorine evolution of IrTaOx anodes via heterojuction with TiO2 film derived from nanoparticle slurry

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