Machine learning screening of high-performance single-atom electrocatalysts for two-electron oxygen reduction reaction.

Electrocatalysis has emerged as one of the most promising alternatives to conventional anthraquinone for preparing hydrogen peroxide (H2O2) with high energy consumption and pollution because of its simplicity, convenience, and environmental friendliness. However, the oxygen reduction reaction (ORR) generating H2O2viathe2e- path is acompetitive path for 4e-ORR to generate H2O. Therefore, it is crucial to identify an electrocatalyst with high selectivity and activity of 2e-ORR. Here, we established five machine learning (ML) models based on the adsorption free energy of O* (△G (O*)) of 149 single-atom catalysts (SACs) collected and the limiting potential (UL) of 31 SACs calculated using density functional theory (DFT) from the literature. We then obtained descriptors that could accurately describe SACs. Furthermore, 690 unknown SACs' 2e-ORR catalytic performance was well predicted. Four 2e-ORR materials with high selectivity and activity were screened: Zn@Pc-N3C1, Au@Pd-N4, Au@Pd-N1C3, and Au@Py-N3C1. We verified the UL of these SACs through DFT calculation, which was higher than the standard value, proving the ML model's validity. The ML-based method to predict the material properties with highly selective and active electrocatalysts provides an efficient, rapid, and low-cost method for discovering and designing more valuable SACs catalysts.

Surface properties of Tetranychus urticae Koch (Acari: Tetranychidae) and the effect of their infestation on the surface properties of kidney bean (Phaseolus vulgaris L.) hosts.

BACKGROUND: The wettability of the target surfaces affects the wetting and deposition of pesticides on them. The properties of leaf surfaces change after infestation by Tetranychus urticae Koch. Studying the surface wettability of T. urticae and the changes in leaf wettability after infestation is important to guide the use of acaricides. RESULTS: The body surface of T. urticae is an ellipsoidal crown covered with dense cuticle striations and hairs arranged in different directions, which makes the surface of T. urticae rough and hydrophobic. The abaxial surfaces of the leaves are rougher and more hydrophobic than the adaxial surfaces. After infestation by T. urticae, the faded spots were sunken on the adaxial surface and raised on the abaxial surface, where they had formed new wide peaks and valleys. The adaxial surface became obviously rougher and more hydrophobic, while the roughness of the abaxial surface became slightly larger, and the change in hydrophobicity was not obvious. The contact angles of the studied commercial acaricide on these surfaces were greater than 65° and were affected by the infestation. Reducing the surface tension can allow for better wetting of these surfaces and eliminate changes in leaf wettability. CONCLUSION: The surfaces of kidney bean leaves became more hydrophobic after infestation by T. urticae with hydrophobic surface. The wettability of the acaricide solution should be adjusted according to the changes in leaf wettability. This study has important theoretical guiding significance for improving effective deposition of acaricide.

Functional magnetic resonance imaging activation of the brain in children: real acupoint versus sham acupoint.

The purpose was to examine the brain activation patterns with acupuncture using real acupoint (Liv3) versus sham acupoint in healthy, sedated children using functional magnetic resonance imaging (fMRI). Functional magnetic resonance imaging scans of the brain for 10 healthy, sedated children were taken during stimulation of real acupoint (Liv3 [Taichong]) and a nearby sham acupoint in a randomized order, employing twisting and nontwisting methods using a blocked paradigm using a 2.0-T scanner. The functional data were analyzed by using SPM 99. Various regions of the brain were activated in 2 acupoints. However, the pattern was different for the 2 acupoints. We suggest specific cerebral activation patterns with acupuncture might explain some of its therapeutic effect.

Effect of acupuncture on the brain in children with spastic cerebral palsy using functional neuroimaging (FMRI).

We study the effect of acupuncture on brain activation patterns in children with cerebral palsy using functional magnetic resonance imaging (fMRI). fMRI of the whole brain was performed in 11 children with cerebral palsy and 10 healthy children during stimulation of a common acupoint in Traditional Medicine [Liv3 (Taichong)] on the left foot. We use both twisting and nontwisting methods with a blocked paradigm on a 2.0 Tesla MRI scanner. Functional data were analyzed by using Statistical Parametric Mapping software (SPM 99). Both signal increase and decrease in various regions of the brain were found in both groups of children. However, the pattern was different for the 2 groups, especially with decreases in signal regions. We suggest that the observed differences between children with cerebral palsy and healthy children with the stimulation of acupoint Liv3 might be due to blockage of the liver meridian in children with cerebral palsy.