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Manganese dioxide (MnO2) is a promising cathode for aqueous Zn batteries owing to its high theoretical capacity and operating voltage. However, it is still confronted with poor conductivity, structural collapse, sluggish ion kinetics, and Jahn–Teller (J–T) distortion. Herein, we propose hydrogen bond-modulated MnO2 by introducing NH4+ (NHMO) for prominent zinc-ion storage. The formation of a hydrogen bond in MnO2 reduces its layer spacing, presenting a more stable structure. The theoretical calculation results demonstrate that the pre-intercalation of NH4+ can effectively reduce the bandgap of the MnO2, enhancing its conductivity. More importantly, the formation of the hydrogen bond can significantly decrease the variation of Mn–O bond length and the proportion of Mn 3dz2 orbitals, meaning that the hydrogen-bond chemistry can effectively suppress J–T distortion. As expected, a high capacity of 287.9 mA h g−1 at 0.1 A g−1 and an ultrahigh rate performance (99.4 mA h g−1 at 6.0 A g−1) can be achieved for the NHMO, as well as a fantastically outstanding cycling stability of 90.0% after 13 000 cycles, far exceeding previously reported Mn-based materials. The rational introduction of a hydrogen bond provides a novel strategy for the development of ultralong lifespan aqueous Zn batteries. [ABSTRACT FROM AUTHOR]

Erianin, a bibenzyl compound found in dendrobium extract, has demonstrated broad anticancer activity. However, its mechanism of action in gastric cancer (GC) remains poorly understood. LKB1 is a tumor-suppressor gene, and its mutation is an important driver of various cancers. Yet some studies have reported contradictory findings. In this study, we combined bioinformatics and in vitro and in vivo experiments to investigate the effect and potential mechanism of Erianin in the treatment of GC. The results show that LKB1 was highly expressed in patients' tumor tissues and GC cells, and it was associated with poor patient prognosis. Erianin could promote GC cell apoptosis and inhibit the scratch repair, migration, invasion, and epithelial–mesenchymal transition (EMT) characteristics. Erianin dose-dependently inhibited the expression of LKB1, SIK2, SIK3, and PARD3 but had no significant effect on SIK1. Erianin also inhibited tumor growth in CDX mice model. Unexpectedly, 5-FU also exhibited a certain inhibitory effect on LKB1. The combination of Erianin and 5-FU significantly improved the anti-tumor efficacy of 5-FU in the growth of GC cells and xenograft mouse models. In summary, Erianin is a potential anti-GC compound that can inhibit GC growth and EMT properties by targeting the LKB1-SIK2/3-PARD3-signaling axis. The synergistic effect of Erianin and 5-FU suggests a promising therapeutic strategy for GC treatment. [ABSTRACT FROM AUTHOR]

Polygonati Rhizoma (PR) has certain neuroprotective effects as a homology of medicine and food. In this study, systematic pharmacology, molecular docking, and in vitro experiments were integrated to verify the antidepressant active ingredients in PR and their mechanisms. A total of seven compounds in PR were found to be associated with 45 targets of depression. Preliminarily, DFV docking with cyclooxygenase 2 (COX2) showed good affinity. In vitro, DFV inhibited lipopolysaccharide (LPS)-induced inflammation of BV-2 cells, reversed amoeba-like morphological changes, and increased mitochondrial membrane potential. DFV reversed the malondialdehyde (MDA) overexpression and superoxide dismutase (SOD) expression inhibition in LPS-induced BV-2 cells and decreased interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and IL-6 mRNA expression levels in a dose-dependent manner. DFV inhibited both mRNA and protein expression levels of COX2 induced by LPS, and the activation of NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) and caspase1 was suppressed, thus exerting an antidepressant effect. This study proves that DFV may be an important component basis for PR to play an antidepressant role. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable zinc-ion batteries (ZIBs) are potential alternative candidates for current commercial lithium-ion batteries due to their cost-efficiency, safety and sustainable nature. As one of the prominent cathode materials, MnO2 exhibits high operating voltage and theoretical capacity. Yet, its poor electrochemical kinetics, low conductivity, and lifespan prevent its further application. Herein, an effective strategy for the construction of hierarchical TiN@MnO2 nanowire arrays (NWAs) core–shell heterostructures directly grown on carbon cloth (CC) is demonstrated to systematically solve the above issues. First-principles calculations reveal that decreased bandgap and Zn2+ diffusion barrier as well as more stable structure of the host material after Zn2+ insertion promote the electrochemical kinetics of TiN@MnO2. As a result, TiN@MnO2 NWAs/CC exhibits significantly increased capacity (385.1 vs. 310 and 194 mA h g−1 at 0.1 A g−1), rate performance (127.6 mA h g−1vs. 49.7 and 37.4 mA h g−1 at 4.0 A g−1) and cycling stability (101.6% capacity retention over 2300 cycles vs. 14.0% and 11.9%) compared with TiO2@MnO2 NWAs/CC and MnO2 NSs/CC, respectively. Finally, the as-assembled flexible ZIBs with TiN@MnO2 NWAs/CC cathode deliver an ultrahigh energy density of 327.7 W h kg−1 at 135.6 W kg−1. The proposition of the core–shell idea provides a novel strategy for development ZIBs. [ABSTRACT FROM AUTHOR]

The multi‐microgrids operation can greatly improve the proportion of renewable energy integration and power reliability of rural microgrids through energy trading between adjacent microgrids. Therefore, this paper proposes an optimization method for the low‐carbon economic operation of rural microgrids which contain wind power, photovoltaic, biogas, and other common rural renewable energy sources. Using the asymmetric Nash bargaining model which can form the non‐linear energy mapping function to quantify the bargaining power of each microgrid to establish the multi‐microgrids energy trading model, and the non‐convex trading optimization problem is equivalently transformed into two convex optimization subproblems, subproblem 1 is microgrids alliance costs containing the emission costs, and subproblem 2 is cooperative benefits distribution. Then, the accelerated Alternating Direction Method of Multipliers (ADMM) method is used to solve subproblem 1 and subproblem 2, respectively, and the privacy of transaction information is also protected. The results show that: compared with the single‐microgrid operation, the combined operation of rural multi‐microgrids with biogas can greatly improve the renewable energy consumption rate, reduce carbon emission, and improve the profit income of the alliance and each microgrid. Meanwhile, the accelerated ADMM algorithm used can greatly improve the solution speed. [ABSTRACT FROM AUTHOR]