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Single-atom catalysts represent a unique catalytic system with high atomic utilization and tunable reaction pathway. Despite current successes in their optimization and tailoring through structural and synthetic innovations, there is a lack of dynamic modulation approach for the single-atom catalysis. Inspired by the electrostatic interaction within specific natural enzymes, here we show the performance of model single-atom catalysts anchored on two-dimensional atomic crystals can be systematically and efficiently tuned by oriented external electric fields. Superior electrocatalytic performance have been achieved in single-atom catalysts under electrostatic modulations. Theoretical investigations suggest a universal "onsite electrostatic polarization" mechanism, in which electrostatic fields significantly polarize charge distributions at the single-atom sites and alter the kinetics of the rate determining steps, leading to boosted reaction performances. Such field-induced on-site polarization offers a unique strategy for simulating the catalytic processes in natural enzyme systems with quantitative, precise and dynamic external electric fields.

How to transfer industrial exhaust gases of nitrogen oxides into high‐values product is significantly important and challenging. Herein, we demonstrate an innovative method for artificial synthesis of essential α‐amino acids from nitric oxide (NO) by reacting with α‐keto acids through electrocatalytic process with atomically dispersed Fe supported on N‐doped carbon matrix (AD‐Fe/NC) as the catalyst. A yield of valine with 32.1 μmol mgcat−1 is delivered at −0.6 V vs. reversible hydrogen electrode, corresponding a selectivity of 11.3 %. In situ X‐ray absorption fine structure and synchrotron radiation infrared spectroscopy analyses show that NO as nitrogen source converted to hydroxylamine that promptly nucleophilic attacked on the electrophilic carbon center of α‐keto acid to form oxime and subsequent reductive hydrogenation occurred on the way to amino acid. Over 6 kinds of α‐amino acids have been successfully synthesized and gaseous nitrogen source can be also replaced by liquid nitrogen source (NO3−). Our findings not only provide a creative method for converting nitrogen oxides into high‐valued products, which is of epoch‐making significance towards artificial synthesis of amino acids, but also benefit in deploying near‐zero‐emission technologies for global environmental and economic development. [ABSTRACT FROM AUTHOR]

Accurately regulating the selectivity of the oxygen reduction reaction (ORR) is crucial to renewable energy storage and utilization, but challenging. A flexible alteration of ORR pathways on atomically dispersed Zn sites towards high selectivity ORR can be achieved by tailoring the coordination environment of the catalytic centers. The atomically dispersed Zn catalysts with unique O‐ and C‐coordination structure (ZnO3C) or N‐coordination structure (ZnN4) can be prepared by varying the functional groups of corresponding MOF precursors. The coordination environment of as‐prepared atomically dispersed Zn catalysts was confirmed by X‐ray absorption fine structure (XAFs). Notably, the ZnN4 catalyst processes a 4 e− ORR pathway to generate H2O. However, controllably tailoring the coordination environment of atomically dispersed Zn sites, ZnO3C catalyst processes a 2 e− ORR pathway to generate H2O2 with a near zero overpotential and high selectivity in 0.1 M KOH. Calculations reveal that decreased electron density around Zn in ZnO3C lowers the d‐band center of Zn, thus changing the intermediate adsorption and contributing to the high selectivity towards 2 e− ORR. [ABSTRACT FROM AUTHOR]

Objective: The aim of this meta-analysis is to provide recommendations for clinical practice and prevention of postoperative complications, such as circumferential resection margin (CRM) involvement, and compare the amount of intraoperative bleeding, safety, operative time, recovery, outcomes, and clinical significance of robot-assisted and conventional laparoscopic procedures in anus-preserving rectal cancer.Methods: A literature search (PubMed) was performed to identify biomedical research papers and abstracts of studies comparing robot-assisted and conventional laparoscopic procedures. We attempted to obtain the full-text link for papers published between 2000 and 2016, and hand-searched references for relevant literature. RevMan 5.3 software was used for the meta-analysis.Results: Nine papers (949 patients) were eligible for inclusion; there were 473 patients (49.8%) in the robotic group and 476 patients (50.2%) in the laparoscopic group. According to the data provided in the literature, seven indicators were used to complete the evaluation. The results of the meta-analysis suggested that robot-assisted procedure was associated with lower intraoperative blood loss (mean difference [MD] -41.15; 95% confidence interval [CI] -77.51, -4.79; P=0.03), lower open conversion rate (risk difference [RD] -0.05; 95% CI -0.09, -0.01; P=0.02), lower hospital stay (MD -1.07; 95% CI -1.80, -0.33; P=0.005), lower overall complication rate (odds ratio 0.58; 95% CI 0.41, 0.83; P=0.003), and longer operative time (MD 33.73; 95% CI 8.48, 58.99; P=0.009) compared with conventional laparoscopy. There were no differences in the rate of CRM involvement (RD -0.02; 95% CI -0.05, 0.01; P=0.23) and days to return of bowel function (MD -0.03; 95% CI -0.40, 0.34; P=0.89).Conclusion: The Da Vinci robot was superior to laparoscopy with respect to blood loss, open conversion, hospital stay, and postoperative complications during anus-preserving rectal cancer procedures; however, conventional laparoscopy had an advantage regarding operative time. The remaining indicators (CRMs and recovery from intestinal peristalsis) did not differ. [ABSTRACT FROM AUTHOR]

Objective: Exploring the core and bridge nodes in problematic social network use and alexithymia among freshmen to provide a basis for understanding the relationship and interventions., Methods: A total of 4057 first-year students from four universities in Shandong Province were chosen and surveyed with the Problematic Mobile Social Media Use Assessment Questionnaire and the Toronto Alexithymia Scale (TAS). Network analysis was performed using R to estimate the connections between nodes. Centrality and predictability indicators were used to identify key nodes, with accuracy and stability validation techniques applied. Gender and residence differences in the network structure were also examined., Results: In the problematic social network use network, the nodes with the highest expected influence were P16 (excessive swiping) and P14 (lack of control over phone usage). In the problematic social network use-alexithymia network, cognitive failure had the highest strength (strength = 1.155) and centrality. Difficulty identifying feelings (bridgestrength = 0.32), externally oriented thoughts (bridgestrength = 0.24), and cognitive failure (bridgestrength = 0.19) were key bridge nodes. No significant differences were found in the network structure across gender and residence, though the network was tightly connected., Conclusion: Cognitive failure plays a central role in problematic social network use among freshmen. Difficulty identifying feelings, externally oriented thoughts, and cognitive failure are critical in linking problematic social network use with alexithymia., Competing Interests: The authors declare that they have no competing interests., (© 2024 Ding et al.)

Acquiring a highly efficient electrocatalyst capable of sustaining prolonged operation under high current density is of paramount importance for the process of electrocatalytic water splitting. Herein, Fe-doped phosphide (Fe-Ni 5 P 4 ) derived from the NiFc metal-organic framework (NiFc-MOF) (Fc: 1,1'-ferrocene dicarboxylate) shows high catalytic activity for overall water splitting (OWS). Fe-Ni 5 P 4 ||Fe-Ni 5 P 4 exhibits a low voltage of 1.72 V for OWS at 0.5 A cm -2 and permits stable operation for 2700 h in 1.0 m KOH. Remarkably, Fe-Ni 5 P 4 ||Fe-Ni 5 P 4 can sustain robust water splitting at an extra-large current density of 1 A cm -2 for 1170 h even in alkaline seawater. Theoretical calculations confirm that Fe doping simultaneously reduces the reaction barriers of coupling and desorption (O * →OOH * , OOH * →O 2 * ) in the oxygen evolution reaction (OER) and regulates the adsorption strength of the intermediates (H 2 O * , H * ) in the hydrogen evolution reaction (HER), enabling Fe-Ni 5 P 4 to possess excellent dual functional activity. This study offers a valuable reference for the advancement of highly durable electrocatalysts through the regulation derived from coordination frameworks, with significant implications for industrial applications and energy conversion technologies., (© 2024 Wiley‐VCH GmbH.)