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The LiOH‐based cathode chemistry has demonstrated potential for high‐energy Li−O2 batteries. However, the understanding of such complex chemistry remains incomplete. Herein, we use the combined experimental methods with ab initio calculations to study LiOH chemistry. We provide a unified reaction mechanism for LiOH formation during discharge via net 4 e− oxygen reduction, in which Li2O2 acts as intermediate in low water‐content electrolyte but LiHO2 as intermediate in high water‐content electrolyte. Besides, LiOH decomposes via 1 e− oxidation during charge, generating surface‐reactive hydroxyl species that degrade organic electrolytes and generate protons. These protons lead to early removal of LiOH, followed by a new high‐potential charge plateau (1 e− water oxidation). At following cycles, these accumulated protons lead to a new high‐potential discharge plateau, corresponding to water formation. Our findings shed light on understanding of 4 e− cathode chemistries in metal–air batteries. [ABSTRACT FROM AUTHOR]

Mechanoluminescence (ML), a novel process that converts mechanical momentum to light emission, has shown potential for sustainable future technologies. However, the lights emitted from classical ML materials have shown broad emission spectra and a limitation in the choice of colors so far, constraining the full‐color implementation of ML. Herein, a quantum dot (QD)‐in‐mechanoluminescent matrix (QMM) architecture is introduced by simply incorporating QDs with the classical ML‐active matrices, designed to utilize the sharp emission spectra of the QDs. The QMMs demonstrate distinctive green and red lights identical to the emissions from the QDs through mechanical stimuli, achieving the purest ML reported to date. Furthermore, the deployments of the QDs allow the full‐color implementation of ML covering a wide color gamut, as well as the demonstration of the purest white reported to date. Systematic investigations reveal that the ML operation in the QMM is governed according to the ML‐stimulated photoluminescence (PL) mechanism, preventing energy or charge transfer processes. Moreover, the QMMs exhibit excellent stabilities upon environmental stresses and the patterned system is readily prepared, guaranteeing both robustness and easy processability of the system. This simple QMM strategy suggests practical insights for the development of powerless ML display and lighting systems. [ABSTRACT FROM AUTHOR]

Background: Ginsenoside Rg-1 (Rg-1), a triterpenoid saponin abundantly present in Panax ginseng, is a type of naturally occurring steroid with known anti-diabetic and anti-inflammatory effects. In this study, we sought to confirm the effects and mechanisms of action of Rg-1 on store-operated Ca2+ entry (SOCE) in human vascular endothelial cell line (EA) and murine aortic vascular smooth muscle cell line (MOVAS) cells exposed to high glucose. Methods: Cytosolic Ca2+ concentrations in EA and MOVAS cells were measured by monitoring fluorescence of the ratiometric Ca2+-indicator, Fura-2 AM. Results: High glucose significantly increased Ca2+ influx by abnormally activating SOCE in EA and MOVAS cells. Notably, this high glucose-induced increase in SOCE was restored to normal levels in EA and MOVAS cells by Rg-1. Moreover, Rg-1 induced reductions in SOCE in cells exposed to high glucose were significantly inhibited by the plasma membrane Ca2+ ATPase (PMCA) blocker lanthanum, the Na+/K+-ATPase blocker ouabain, or the Na+/Ca2+ exchanger (NCX) blockers Ni2+ and KB-R7943. These observations suggest that the mechanism of action of Rg-1 inhibition of SOCE involves PMCA and Na+/K+-ATPase, and an increase in Ca2+ efflux via NCXs in both EA and MOVAS cells exposed to high glucose. Conclusions: These findings indicate that Rg-1 may protect vascular endothelial and smooth muscle cells from Ca2+ increases following exposure to hyperglycemic conditions. [ABSTRACT FROM AUTHOR]