The development of ultrastable carbon materials for potassium storage poses key limitations caused by the huge volume variation and sluggish kinetics.N itrogen-enriched porous carbons have recently emerged as promising candidates for this application;h owever,r ational control over nitrogen doping is needed to further suppress the long-term capacity fading. Here we propose astrategy based on pyrolysis-etching of apyridine-coordinated polymer for deliberate manipulation of edge-nitrogen doping and specific spatial distribution in amorphous high-surface-area carbons;t he obtained material shows an edge-nitrogen content of up to 9.34 at %, richer N distribution inside the material, and high surface area of 616 m 2 g À1 under ac ost-effective low-temperature carbonization. The optimizedc arbon delivers unprecedented K-storage stability over 6000 cycles with negligible capacity decay (252 mA hg À1 after 4months at 1Ag À1), rarely reported for potassium storage.

Enhancing ionic conductivity of quasi‐solid‐state electrolytes (QSSEs) is one of the top priorities, while conventional metal–organic frameworks (MOFs) severely impede ion migration due to their abundant grain boundaries. Herein, ZIF‐4 glass, a subset of MOFs, is reported as QSSEs (LGZ) for lithium‐metal batteries. With lean Li content (0.12 wt%) and solvent amount (19.4 wt%), LGZ can achieve a remarkable ion conductivity of 1.61 × 10−4 S cm−1 at 30 °C, higher than those of crystalline ZIF‐4‐based QSSEs (LCZ, 8.21 × 10−5 S cm−1) and the reported QSSEs containing high Li contents (0.32–5.4 wt%) and huge plasticizer (30–70 wt%). Even at −56.6 °C, LGZ can still deliver a conductivity of 5.96 × 10−6 S cm−1 (vs 4.51 × 10−7 S cm−1 for LCZ). Owing to the grain boundary‐free and isotropic properties of glassy ZIF‐4, the facilitated ion conduction enables a homogeneous ion flux, suppressing Li dendrites. When paired with LiFePO4 cathode, LGZ cell demonstrates a prominent cycling capacity of 101 mAh g−1 for 500 cycles at 1 C with the near‐utility retention, outperforming LCZ (30.7 mAh g−1) and the explored MOF‐/covalent–organic frameworks (COF)‐based QSSEs. Hence, MOF glasses will be a potential platform for practical quasi‐solid‐state batteries in the future.

The catalytic enantioselective synthesis of all-carbon quaternary stereogenic centers in spirocyclic diketones has been achieved for the first time by an unprecedented asymmetric vinylogous alpha-ketol rearrangement in which an enantiocontrolled semipinacol-type 1,2-carbon migration was realized using multifunctional cinchona-modified primary amine catalysis.

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The bi-directional regulation of TGF-beta1 (transforming growth factor-beta1) on fibroblast proliferation with stimulation at low concentration, but inhibition at high concentration, has important significance during tissue repair. The mechanism has not been defined. c-Ski is a major co-repressor of TGF-beta1/Smad3 signalling; however, the exact role of c-Ski in the bi-directional regulation of fibroblast proliferation remains to be determined. In the present study, we established a dose-effect relationship of bi-directional regulation of TGF-beta1-mediated proliferation in rat skin fibroblasts, and found that c-Ski overexpression promoted fibroblast proliferation by inhibiting Smad3 activity. Importantly, c-Ski expression was decreased at the high concentration of TGF-beta1, but increased at the low concentration of TGF-beta1. This dose-dependent change in TGF-beta1 action did not affect Smad3 phosphorylation or nuclear translocation, but altered Smad3 DNA-binding activity, transcriptional activity and expression of the downstream gene p21 that both increased at the high concentration and decreased at the low concentration. Furthermore, c-Ski overexpression exerted synergistic stimulation with TGF-beta1 at the low concentration, but reversed the inhibitory effect of TGF-beta1 at high concentrations, while knockdown of c-Ski by RNA interference abrogated bi-directional role of TGF-beta1 on fibroblast proliferation. Thus our data reveal a new mechanism for this bi-directional regulation, i.e. c-Ski expression change induced by low or high TGF-beta1 concentration in turn determines the promoting or inhibiting effects of TGF-beta1 on fibroblast proliferation, and suggests an important role of c-Ski that modulates the local availability of TGF-beta1 within the wound repair microenvironment.

Methane hydrate confined in porous materials is postulated as an alternative energy storage strategy. By applying model carbons with ordered and uniformly sized pores and a combination of advanced in situ characterization techniques, we address fundamental questions on the formation mechanism of methane hydrate in confinement. Here, we provide experimental evidence for the presence of methane hydrate inside confined spaces by in situ small- and wide-angle neutron scattering, X-ray diffraction, and high-pressure gas adsorption techniques. Furthermore, we demonstrate how the carbon surface chemistry tremendously impacts the methane hydrate formation kinetics and storage capacity. Our findings represent a substantial step toward transforming a naturally occurring phenomenon into a feasible energy storage technology.

A new asymmetric capacitor concept is proposed providing high energy storage capacity for only one charging direction. Size‐selective microporous carbons (w<0.9 nm) with narrow pore size distribution are demonstrated to exclusively electrosorb small anions (BF4−) but size‐exclude larger cations (TBA+ or TPA+), while the counter electrode, an ordered mesoporous carbon (w>2 nm), gives access to both ions. This architecture exclusively charges in one direction with high rectification ratios (RR=12), representing a novel capacitive analogue of semiconductor‐based diodes (“CAPode”). By precise pore size control of microporous carbons (0.6 nm, 0.8 nm and 1.0 nm) combined with an ordered mesoporous counter electrode (CMK‐3, 4.8 nm) electrolyte cation sieving and unidirectional charging is demonstrated by analyzing the device charge‐discharge response and monitoring individual electrodes of the device via in situ NMR spectroscopy.