Short periods of bipolar anodal TDCS induce no instantaneous dose-dependent increase in cerebral blood flow in the targeted human motor cortex

Background: Anodal transcranial direct current stimulation (aTDCS) of primary motor hand area (M1-HAND) can enhance corticomotor excitability. Yet, it is still unknown which current intensity produces the strongest effect on regional neural activity. Magnetic resonance imaging (MRI) combined with pseudo-continuous Arterial Spin Labeling (pc-ASL MRI) can map regional cortical blood flow (rCBF) and may thus be useful to probe the relationship between current intensity and neural response at the individual level. Objective: Here we employed pc-ASL MRI to map acute rCBF changes during short-duration aTDCS of left M1-HAND. Using the rCBF response as a proxy for regional neuronal activity, we investigated if short-duration aTDCS produces an instantaneous dose-dependent rCBF increase in the targeted M1-HAND that may be useful for individual dosing. Methods: Nine healthy right-handed participants received 30 seconds of aTDCS at 0.5, 1.0, 1.5, and 2.0 mA with the anode placed over left M1-HAND and cathode over the right supraorbital region. Concurrent pc-ASL MRI at 3 T probed TDCS-related rCBF changes in the targeted M1-HAND. Movement-induced rCBF changes were also assessed. Results: Apart from a subtle increase in rCBF at 0.5 mA, short-duration aTDCS did not modulate rCBF in the M1-HAND relative to no-stimulation periods. None of the participants showed a dose-dependent increase in rCBF during aTDCS, even after accounting for individual differences in TDCS-induced electrical field strength. In contrast, finger movements led to robust activation of left M1-HAND before and after aTDCS. Conclusion: Short-duration bipolar aTDCS does not produce instantaneous dose-dependent rCBF increases in the targeted M1-HAND at conventional intensity ranges. Therefore, the regional hemodynamic response profile to short-duration aTDCS may not be suited to inform individual dosing of TDCS intensity.

Degradation of Azo Dyes with Different Functional Groups in Simulated Wastewater by Electrocoagulation

Increasing attention has been paid to the widespread contamination of azo dyes in water bodies globally. These chemicals can present high toxicity, possibly causing severe irritation of the respiratory tract and even carcinogenic effects. The present study focuses on the periodically reverse electrocoagulation (PREC) treatment of two typical azo dyes with different functional groups, involving methyl orange (MO) and alizarin yellow (AY), using Fe-Fe electrodes. Based upon the comparative analysis of three main parameters, including current intensity, pH, and electrolyte, the optimal color removal rates for MO and AY could be achieved at a rate of up to 98.7% and 98.6%, respectively, when the current intensity is set to 0.6 A, the pH is set at 6.0, and the electrolyte is selected as NaCl. An accurate predicted method of response surface methodology (RSM) was established to optimize the PREC process involving the three parameters above. The reaction time was the main influence for both azo dyes, while the condition of PREC treatment for AY simulated wastewater was time-saving and energy conserving. According to the further UV–Vis spectrophotometry analysis throughout the procedure of the PREC process, the removal efficiency for AY was better than that of MO, potentially because hydroxyl groups might donate electrons to iron flocs or electrolyze out hydroxyl free radicals. The present study revealed that the functional groups might pose a vital influence on the removal efficiencies of the PREC treatment for those two azo dyes.

The Effect of Electroacupuncture Treatment with Different Intensities for Functional Diarrhea: A Randomized Controlled Trial

Background. Electroacupuncture (EA) may have a role in the treatment of diarrhea symptoms. However, the efficacy and safety of EA with different current intensities in improving gastrointestinal function, psychology, and quality of life (QOL) of functional diarrhea (FD) remain unknown. Objective. To investigate the efficacy and safety of EA with different current intensities in improving gastrointestinal function, psychology, and QOL for FD patients. Methods. 73 FD patients were randomly divided into three groups: low current intensity group (LI) of EA, high current intensity group (HI) of EA, and loperamide control group (LC). Four weeks of treatment were provided in the three groups. The primary outcome was the proportion of normal defecation. Additional outcomes included the change from baseline for the weekly spontaneous bowel movements (SBMs) and the change from baseline for the mean Bristol Stool Form Scale (BSFS). QOL was assessed by the 36-item short-form health survey (SF-36). Self-rating Anxiety Scale (SAS) and Self-rating Depression Scale (SDS) were used to assess the psychology state. Results. Low current intensity of EA significantly improved the proportion of normal defecation during treatment and follow-up period ( P < 0.01 ). EA significantly improves the mean BSFS scores and weekly SBMs, and this efficacy is equivalent to loperamide ( P < 0.05 ). The SF-36 scores of general health in LI and HI groups and vitality and mental health in LI group were significantly increased compared to baseline ( P < 0.05 ). Low current intensity of EA can significantly improve SAS and SDS scores ( P < 0.05 ). Conclusions. EA significantly improved stool consistency and weekly SBMs in FD patients. Compared with loperamide, low current intensity of EA may have a better sustainable effect in restoring normal defecation in patients with FD, and it can also effectively improve QOL, anxiety, and depression. However, larger sample sizes are needed to determine safety and efficacy. Trial registration number: NCT01274793.

Decolorization of industrial wastewater using electrochemical peroxidation process

In this study, decolorization of wastewater samples taken from the paper industry is investigated using electrochemical peroxidation process. The electrochemical peroxidation process is a part of electrochemical advanced oxidation processes, which is based on the Fenton’s chemical reaction, provided by addition of external H2O2 into reaction cell. In this study, iron is used as anode and graphite as cathode put at the fixed distance of 30 mm in a glass reaction cell. The cell was filled with the solution containing wastewater and sodium chloride as the supporting electrolyte. Factors of the process such as pH, current intensity, hydrogen peroxide concentration, and time of treatment were studied. The results illustrate that all these parameters affect efficiencies of dye removal and chemical oxygen demand (COD) reducing. The maximal removal of wastewater contaminants was achieved under acid (pH 3) condition, with the applied current of 1 A, and hydrogen peroxide concentration of 0.033 M. At these conditions, decolorization process efficiency reached 100 and 83 % of COD removal after 40 minutes of wastewater sample treatment. In addition, the electrical energy consumption for wastewater treatment by electrochemical peroxidation is calculated, showing increase as the current intensity of treatment process was increased. The obtained results suggest that electrochemical peroxidation process can be used for removing dye compounds and chemical oxygen demand (COD) from industrial wastewaters with high removal efficiency.

Diagnostics of the Excessive Wear of the Machine on a Model of Developmental, Progressive Interactions Between Diagnostic Signals and Rotation Speed Signals

In the machine operating process, there are certain interactions between its operational use and wear. The current wear is increased by the current intensity of operational use, and usable potential is reduced by the current wear rate. In the diagnostic inference process, static characteristics and trajectories of state from the experiment are compared with different matrices determined for various assumed configurations of changes. As a result, the approximated diagnosis is created. This method is not universal. It applies only to the continuous progressive state, more or less increased wear rate of the machine.

Conversion Method of Thermionic Emission Current to Voltage for High-Voltage Sources of Electrons

The stability of the electron thermionic emission current is one of the most important requirements for electron sources used, inter alia, in evaporators, production of rare gas excimers, and electron beam objects for high energy physics. In emission current control systems, a negative feedback signal, directly proportional to the emission current is transferred from the high-voltage anode circuit to the low-voltage cathode circuit. This technique, especially for high-voltage sources of electrons, requires the use of galvanic isolation. Alternatively, a method of converting the emission current to voltage in the cathode power supply circuit was proposed. It uses a linear cathode current intensity distribution and multiplicative-additive processing of two voltage signals, directly proportional to the values of cathode current intensity. The simulation results show that a relatively high conversion accuracy can be obtained for low values of the electron work function of the cathode material. The results of experimental tests of the dynamic parameters of the electron source and the steady-state Ie-V characteristic of the converter are presented. The implementation of the proposed Ie-V conversion method facilitates the design of the emission current controller, especially for high-voltage sources of electrons, because a negative feedback loop between the anode and cathode circuits is not required, all controller sub-components are at a common electrostatic potential.

Electrochemical Recovery to Overcome Direct Osmosis Concentrate-Bearing Lead: Optimization of Treatment Process via RSM-CCD

The use of electrochemistry is a promising approach for the treatment of direct osmosis concentrate that contains a high concentration of organic pollutants and has high osmotic pressure, to achieve the safe discharge of effluent. This work addresses, for the first time, this major environmental challenge using perforated aluminum electrodes mounted in an electrocoagulation–flotation cell (PA-ECF). The design of the experiments, the modeling, and the optimization of the PA-ECF conditions for the treatment of DO concentrate rich in Pb were explored using a central composite design (CCD) under response surface methodology (RSM). Therefore, the CCD-RSM was employed to optimize and study the effect of the independent variables, namely electrolysis time (5.85 min to 116.15 min) and current intensity (0.09 A to 2.91 A) on Pb removal. Optimal values of the process parameters were determined as an electrolysis time of 77.65 min and a current intensity of 0.9 A. In addition to Pb removal (97.8%), energy consumption, electrode mass-consumed material, and operating cost were estimated as 0.0025 kWh/m3, 0.217 kg Al/m3, and 0.423 USD/m3, respectively. In addition, it was found that DO concentrate obtained from metallurgical wastewater can be recovered through PA-ECF (almost 94% Pb removal). This work demonstrated that the PA-ECF technique could became a viable process applicable in the treatment of DO concentrate containing Pb-rich for reuse.

Cds nanocrystal enhanced TiO2photoelectrochemical aptasensor for sensitive detection of cytochrome c

A CdS nanocrystal enhanced TiO2 nanotubes (CdS@TiO2 NATs) photoelectrode was prepared via successive ionic layer adsorption and reaction (SILAR) of CdS on the surface of TiO2 NATs. A HS-aptamer owing a specific binding toward cytochrome c was modified onto the CdS@TiO2 NATs, which resulting a decrease in the photoelectrical current intensity. Cytochrome c is therefore quantified based on the decrease in photoelectrical current. High specificity and high sensitivity were obtained with a linear range from 3 pM to 80 nM, and a limit of detection of 2.53 pM.

Electrodeposition of Calcium Carbonate and Magnesium Carbonate from Hard Water on Stainless-Steel Electrode to Prevent Natural Scaling Phenomenon

This study focuses on preventing scale formation in hard waters by controlled electrode-position of Ca2+ and Mg2+ on a stainless-steel cathode at constant applied current intensity. The influence of the anode material, BDD or Ti/Pt/PbO2, cathode active area, stirring speed, and applied anodic current intensity on the inorganic carbon (IC), Ca2+, and Mg2+ removal was investigated. Assays were performed with model hard water solutions, simulating Bounouara (Algeria) water. The scaling inhibiting properties of the treated water were followed by measuring IC, calcium, and magnesium concentrations and chronoamperometric characterization of the treated solutions. The influence of the Ca/Mg molar ratio on the inorganic carbon removal by electrolysis was also evaluated, utilizing model solutions with different compositions. It was found that an increase in stirring speed or cathode geometric area favors IC and Ca2+ and Mg2+ removal rates. The applied current intensity was varied from 0.025 to 0.5 A, and the best results were obtained for 0.1 A, either in IC and Ca2+ and Mg2+ removals or by the accelerated scaling tests. However, energy costs increase with applied current. The deposit formed over the cathode does not seem to influence posterior deposition rate, and after eight consecutive assays, the solid deposition rate was kept constant. Ca/Mg ratio influences IC removal rate that increases with it. The results showed that hard-water scaling phenomena can be prevented by solid electrodeposition on the cathode at applied constant current.

Chaotic Resonance in Izhikevich Neural Network Motifs Under Electromagnetic Induction

Chaotic resonance (CR) is the response of a nonlinear system to weak signals enhanced by internal or external chaotic activity (such as the signal derived from Lorenz system). In this paper, the triple-neuron feed-forward loop (FFL) Izhikevich neural network motifs with eight types are constructed as the nonlinear systems, and the effects of EMI on CR phenomenon in FFL neuronal network motifs are studied. It is found that both the single Izhikevich neural model under electromagnetic induction (EMI) and its network motifs exhibit CR phenomenon depending on the chaotic current intensity. There exists an optimal chaotic current intensity ensuring the best detection of weak signal in single Izhikevich neuron or its network motifs via CR. The EMI can enhance the ability of neuron to detect weak signals. For T1-FFL and T2-FFL motifs, the adjustment of EMI parameters makes T2-FFL show a more obvious CR phenomenon than that for T1-FFL motifs, which is different from the impact of system parameters (e.g., the weak signal frequency, the coupling strength, and the time delay) on CR. Another interesting phenomenon is that the variation of CR with time delay exhibits quasi periodic characteristics. Our results showed that CR effect is a robust phenomenon which is observed in both single Izhikevich neuron and network motifs, which might help one understand how to improve the ability of weak signal detection and propagation in neuronal system.